Lie Groupoids

A Lie groupoid can be thought of as a generalization of a Lie group in which the multiplication is only defined for certain pairs of elements. From another perspective, Lie groupoids can be regarded as manifolds endowed with a type of action codifying internal and external symmetries. The vigorous development of their theory in the last few decades has been largely stimulated by their connections with such areas as Poisson geometry and non-commutative geometry, as well as several topics in mathematical physics, including classical mechanics, quantization and topological field theories. This article is an overview on Lie groupoids, including basic definitions, key examples and constructions, and topics such as actions and representations, local models, Morita equivalence and cohomology.Comment: Contribution to Encyclopedia of Mathematical Physic

Lithic raw material procurement and consumption during the Late Neolithic/Early Chalcolithic: the case of Casal dos Matos and Cabeça Gorda 1 (Vila Nova de Ourém, Estremadura, Portugal)

Este trabajo presenta la relación entre una potencial fuente de suministro de sílex (Casal dos Matos) y un yacimiento neolítico-calcolítico (Cabeça Gorda 1) ubicado en su entorno inmediato. La comparación macroscópica entre la materia prima utilizada para los artefactos de piedra tallada en Cabeça Gorda 1 y la que ocurre en Casal dos Matos sugiere una relación, al menos espacial, entre un área de suministro local y un contexto de consumo específico – reforzando así la evidente continuidad entre sitios de suministro local, producción y consumo en la Prehistoria de las antiguas comunidades campesinas en la Estremadura portuguesa, entre el Neolítico final y el Calcolítico inicial (3100-2600 cal ANE). Este trabajo no pretende presentar el estudio exhaustivo de la industria de la piedra tallada de Cabeça Gorda 1, pero sí establecer un marco conceptual, basado en los datos actualmente disponibles, para un modelo específico de explotación de materias primas mediante la comparación con otros casos de suministro de sílex en la misma región. Este marco conceptual puede utilizarse, no sólo para el área donde estos sitios se incluyen, sino también para otras regiones donde se pueden identificar contextos similares.This paper presents the relationship between a potential flint procurement source (Casal dos Matos) and a Neolithic- Chalcolithic site (Cabeça Gorda 1) located in its immediate surroundings. The macroscopical comparison between the raw material used for flaked stone artifacts in Cabeça Gorda 1 and the raw material that occurs in Casal dos Matos suggests at least a spatial relationship between a local procurement area and a specific consumption context – thus reinforcing the evident continuity between local procurement, production and consumption sites in the Prehistory of the ancient peasant communities in the Portuguese Estremadura, between the Late Neolithic and Early Chalcolithic (3100-2600 cal BCE). This paper is not intended to present the exhaustive study of the flaked stone industry of Cabeça Gorda 1, but to set a conceptual framework, based on the currently available data, for a specific model of raw material exploitation by comparing with other instances of flint procurement in the same region. This conceptual framework can then be used not only for the area where these sites are included but also for other regions where similar contexts can be identified

Raw material sourcing in the Middle Paleolithic site of Gruta da Oliveira (Central Limestone Massif, Estremadura, Portugal)

The cave site of Gruta da Oliveira is located in the Almonda karst system, at the interface between the Central Limestone Massif of Portuguese Estremadura (CLM) and the adjacent Sedimentary Basin of the River Tagus (TSB). The cave presents a stratification dated to ~37-107 ka containing hearth features, Neanderthal skeletal remains, as well as fauna, microfauna and wood charcoal remains. The lithic assemblages are large and feature a diverse range of raw materials.Knappable lithic raw materials in primary, sub-primary and secondary position in the CLM and the TSB were systematically surveyed and sampled. The characterization of the geological samples was carried out at both the macro- and the microscopic scales and data were systematized under the petroarcheological and “evolutionary chain of silica” approaches.The study of the lithic assemblage from layer 14 (dated to the ~61-93 ka 95.4% probability interval by TL) indicates that the Gruta da Oliveira Neanderthals used quartzite, quartz and flint from sources located less than 30 km away in both the CLM and the TSB

An insight into the histopathology caused by the tick Rhipicephalus sanguineus (Acarina: Ixodidae) in the skin of previously infested, vaccinated or tick-bite naive dogs, guinea pigs and hamsters

Dogs', guinea pigs' and hamsters’ local skin reaction to the attachment and feeding of the tick Rhipicephalus sanguineus were analysed under light microscopy. The hosts were either tick-bite naive, previously infested or vaccinated with crude unfed adult tick extract. Biopsies were taken at the end of each infestation. Changes common to every host, regardless of experimental group, included presence of tick or its mouthparts embedded in a cone of cementum at the surface of the skin, epidermal hyperplasia, hyperkeratosis and acanthosis, edema and copious inflammatory cell infiltration in the dermis, underneath the tick attachment site. Dogs in all experimental groups reacted with an almost exclusive PMN neutrophil accumulation, while guinea pigs showed a predominantly mononuclear cell infiltration in every experimental group. Hamsters suffering first infestations had a mainly neutrophilic infiltration, showed a predominantly mononuclear cell infiltration in response to multiple infestations, and when previously vaccinated this host had a predominantly eosinophilic infiltration. The persistence of PMN neutrophils in dogs suggest a control of the local immune inflammatory response by the tick. The predominantly eosinophilic infiltration in previously vaccinated hamsters might indicate that different immune mechanisms were triggered by infestation and vaccination.Analisou-se, sob microscopia óptica, reação cutânea de cães, hamsters e cobaia à fixação e alimentação do carrapato Rhipicephalus sanguineus. Os hospedeiros empregados foram previamente infestados ou vacinados com extrato total de carrapato adulto não alimentado ou eram livres de contato anterior com o carrapato. Biópsias foram obtidas ao final de cada infestação. As alterações comuns a todos os hospedeiros, independente do grupo experimental, incluíram a presença de carrapato ou de suas peças bucais embutidos em um cone de cemento na superfície da pele, hiperplasia da epiderme, hiperqueratose e acantose, edema e infiltração celular inflamatória intensa na derme abaixo do ponto de fixação do carrapato. Os cães, em todos os grupos experimentais, reagiram com um acúmulo praticamente exclusivo de neutrófilos polimorfonucleares enquanto cobaias exibiram uma infiltração celular predominantemente mononuclear nas diversas condições experimentais. Hamsters sofrendo primeira infestação apresentaram uma infiltração predominantemente neutrofílica, infiltração predominantemente mononuclear em resposta a múltiplas infestações e, quando vacinados, uma infiltração preponderantemente eosinofílica. A persistência de neutrófilos nos cães sugere um controle local da resposta inflamatória imune pelo carrapato. A infiltração predominantemente eosinofílica em hamsters vacinados poderia indicar que mecanismos imunes diferentes foram desencadeados pela infestação e vacinação

Genetic diversity of two Portuguese populations of the pullet carpet shell Venerupis senegalensis, based on RAPD markers: contribution to a sustainable restocking program

The pullet carpet shell Venerupis senegalensis (=V. pullastra) is a commercially important species in Portugal, Spain, France, and Italy. In Portugal, this species was once abundant in the Ria Formosa (southern Portugal

We will be known by the tracks we leave behind: Exotic lithic raw materials, mobility and social networking among the Côa Valley foragers (Portugal)

The aim of this study is to establish different socio-cultural models based on lithic raw material sourcing integrated with regional rock art distributions to infer social behaviours within the context of central Iberian Upper Palaeolithic societies. Specifically, we focus on Upper Palaeolithic hunter–gatherer mobility and social interaction in the Côa Valley. This study relies on a knowledge of regional geology and field work to identify the sources of the lithic raw material found at Côa Valley Upper Palaeolithic sites. We expose the context of use and discard of flint, which is naturally absent from the region, and other local materials. From this, we present a GIS based analysis concerning space, time and least-cost paths travelled. This analysis, along with the environmental data available, forms a baseline to evaluate different anthropological models on hunter–gatherer lithic use, mobility, and social networks. We conclude with a three-level model for social interaction, in the context of aggregation activities between different social meta-groups, which involves embedded procurement, long-distance raw material exchange, and symbolic community, reflected in the largest known open-air Upper Palaeolithic rock art concentration.info:eu-repo/semantics/publishedVersio

Adaptation to Resources and Environments during the Last Glacial Maximum by Hunter-Gatherer Societies in Atlantic Europe

Solutrean culture has been interpreted as a response to the Last Glacial Maximum in western Europe. However, to establish a link depends of our knowledge of the impact of global climatic changes at a local level and of the differential preservation and significance of the record. The identification of lithic sources, technology, function, and place of discard, is an effective way to mitigate some of these biases and to improve our understanding of hunter-gatherer societies. We present the results of a study of flint materials found in several rockshelters and open-air sites preserving Upper Solutrean lithic assemblages from France and Portugal, using a Geographic Information System. The network defined by a least-cost algorithm is considered a proxy for social and territoriality reconstruction. Our goal is to identify recurrences and differences in Solutrean raw material network and management as compared with Middle Paleolithic and Upper Paleolithic assemblages in the same areas, considering environmental changes.info:eu-repo/semantics/publishedVersio

O aprovisionamento de matérias-primas líticas na gruta de Oliveira (Torres Novas)

Tese de mestrado em Geoarqueologia, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2012O estudo das matérias‐primas provenientes de uma amostra da unidade estratigráfica 14 da Gruta da Oliveira, datada de cerca de 45.000 anos, foi conduzido segundo uma metodologia de observação a diferentes escalas. Numa primeira fase, com o auxílio de bibliografia específica, foram definidas e prospectadas as potenciais áreas de aprovisionamento, tendo sido identificados e amostrados 21 afloramentos de rochas em posição primária e secundária no Maciço Calcário Estremenho e na Bacia Sedimentar do Tejo. O estudo foi centrado no sílex. Foram realizadas análises petrográficas à escala macro e microscópica, focadas nas características genéticas e pós‐genéticas dos materiais, permitindo a classificação de 11 tipos distintos. Considerando que o estudo de proveniências deve ser encarado como o primeiro passo da Chaîne Opératoire, dando assim uma dimensão espacial da tecnologia, o material arqueológico foi classificado tipologicamente e segundo classes tecnológicas, num total de 3071 artefactos líticos talhados. O sílex foi analisado petrograficamente, à escala macroscópica, tendo sido identificados seis tipos genéticos. Com estes resultados, cruzados com os dados provenientes das amostras geológicas, foi possível verificar que o aprovisionamento de matérias‐primas foi realizado de modos distintos. O quartzo e quartzito, especialmente o de “grão fino”, ocorrem localmente, enquanto que o sílex provém de afloramentos localizados num raio de 30 km ao redor da gruta. Ainda que ocorra localmente foi explorado na sua maioria pelo menos a cerca de 15 km a Sudoeste da gruta. O aprovisionamento em sílex do Oxfordiano a cerca de 25 km a Nordeste, num corredor natural desenvolvido ao longo do vale do rio Nabão, pode ser interpretado no quadro da ocupação do território relacionada com as modalidades de exploração dos recursos pelos grupos neandertais. Os resultados obtidos permitiram abrir uma janela à compreensão da mobilidade das populações neandertais durante Paleolítico médio final nesta região do país, o que nos possibilita uma abordagem, até agora inexistente, à economia e subsistência destes grupos humanos.The study of raw materials in a sample from Gruta da Oliveira stratigraphic unit 14, dated to ~45,000 years ago, was conducted using a methodology that emphasizes observation at multiple scales. Through an initial review of the literature, potential procurement areas were defined and surveyed. Eventually, 21 outcrops were identified and sampled in both primary and secondary position in the Estremadura Limestone Massif and in the Sedimentary Basin of the Tagus River. Petrographic analyses, focused mainly on the chert, were conducted at macro and microscopic scales allowing the identification of 11 distinct types based on the genetic and post‐genetic characteristics of the rocks. The sourcing study, which should be considered the first step in the reconstruction of the chaîne opératoire gives a spatial dimension to technological organization at Gruta da Oliveira. Among the archaeological material, a total of 3071 lithic artifacts typologically and technologically classified, six genetic types of chert were identified, through petrographical study at a macroscopical scale. Combined with the data from the geological samples, the artifact analysis showed that two kinds of raw material procurement were in existence. Quartz and quartzite, especially the "fine grained" materials, occur locally. The chert comes from a 30 km radius. Some occurs locally, but it was mostly collected at sources located at least 15 km to the southwest; one particular type of flint from the Oxfordian has its closest sources some 25 km to the northeast, along the natural corridor represented by the valley of the Nabão River. These results, obtained through a methodological approach that hitherto remained to be applied to the sites of this region/period, provide novel insights into Neanderthal mobility, economy, and subsistence during the late Middle Paleolithic of Portugal

Isolation, modeling and phytosome forms of antimicrobial and antiproliferative compounds from plectranthus spp.

Diretores de Tese : Dra. Patrícia Rijo ; Dra. Catarina Reis ; Dra. Ana Mª Díaz-LanzaOs produtos naturais têm sido uma valiosa fonte de novos produtos farmacêuticos. As plantas de género Plectranthus L'Her (Lamiaceae) possuem uma ampla diversidade de usos etnomedicinais, que correspondem a uma indicação da presença de potenciais fármacos na sua composição. Métodos inovadores para a veiculação dos produtos naturais, como os fitossomas, demostraram ser uma estratégia promissora para a melhora da veiculação e estabilidade destes produtos. Três plantas do género Plectranthus foram estudadas: P. madagascariensis, P. neochilus e P. porcatus. Extratos foram preparados pela conjugação de técnicas de extração como infusão, decocção, maceração, micro-ondas, ultrassons ou de extração por fluidos supercríticos, utilizando como solventes água, acetona, metanol ou dióxido de carbono supercrítico. Os extratos preparados foram perfilados por HPLC-DAD e identificados alguns dos principais componentes, por comparação com padrões, verificando-se na sua constituição polifenois, diterpenos e flavonoides. Os mesmos extratos foram avaliados em termos das suas atividades antimicrobiana (bactérias de Gram positivo, Gram negativo e leveduras), antioxidante (captura de radicais) e citotóxica (células MDA-MB-231). Extratos de P. madagascariensis (maceração e ultrassons em acetona) e P. neochilus (ultrassons em acetona) apresentaram efeitos antibacterianos contra Bacillus subtilis, Staphylococcus aureus, S. epidermidis e Klebsiella pneumoniae. O extrato de ultrassons de P. madagascariensis obtido com acetona apresentou potentes efeitos antibacterianos em espécies de Staphylococcus, incluindo uma estirpe resistente à meticilina, verificando-se uma concentração mínima inibitória no intervalo de 1,95 a 7,81 μg/mL. Esta atividade encontra-se de acordo com os usos tradicionais destas plantas como agente anti-infecioso. Os extratos metanolicos apresentaram potentes efeitos antioxidantes a uma concentração de extrato de 100 ng/mL (60,8-89,0%). O extrato de maceração em acetona de P. madagascariensis apresentou alguns efeitos citotóxicos na linha celular de cancro de mama MDA-MB-231 com um IC50 de 64,52 mg/mL. Uma vez que os extratos mais bioativos foram obtidos a partir de P. madagascariensis, estes foram caracterizados em maior detalhe com identificação e quantificação dos principais compostos nesses extratos. Quatro compostos foram identificados por comparação com padrões: ácido rosmarinico, 7α,6β-dihidroxiroyleanona, 7α-acetoxi-6β-hidroxiroileanona e coleona U. Um composto diterpenico foi isolado a partir do extrato de ultrassons com acetona de P. madagascariensis e caracterizado por RMN de 1H e 13C como 7α-formiloxi-6β-hidroxiroileanona. Este composto foi isolado pela primeira vez a partir desta planta. Os efeitos citotóxicos dos compostos purificados foram determinados numa bateria de linhas celulares de cancro e em conjugação com dados da literatura, foram estabelecidas algumas relações de estrutura-atividade na estrutura abietanica do tipo roileanona. Foi observada alguma seletividade para linhas celulares de cancro por parte da 7α,6β-dihidroxiroileanona e 7α-acetoxi-6β-hidroxiroileanona com com índice de seletividade de 4,3 e 3,2 respetivamente.O extrato com maior potência antibacteriana identificado na triagem inicial foi selecionado para sua incorporação numa formulação fitossomal com posterior encapsulação por quitosano. Os fitossomas obtidos apresentavam-se amorfos, uniformes na forma (SEM e AFM), com um tamanho médio de 1082 ± 363 nm e potencial zeta de 20,59 ± 12,02 mV. A eficiência de encapsulação determinada por HPLC (57,7 ± 0,06%). A existência de interações entre os componentes da formulação foi analisada por A ocorrência de encapsulação foi demonstrada por DSC e DRIFTS. Os fitossomas demonstraram uma libertação sustentada com redução da permeação trans-cutanea. Uma melhoria em até 4 vezes na atividade anti-estafilococo (concentração mínima inibitória de 0,49 a 31,25 mg/ml). A segurança desta formulação foi demonstrada por baixa citotoxicidade em queratinocitos humanos in vitro e por irritação negligenciável in vivo nos ensaios de irritação cutânea aguda e sub-crónica em ratinhos. Este estudo demonstrou o potencial do género Plectranthus como fonte de novos agentes antibacterianos justificando-se alguns dos usos etnomedicinais destas plantas. Os diterpenos do tipo abietano isolados a partir de P. madagascariensis possuem efeitos citotóxicos com alguma seletividade face a algumas linhas celulares de cancro. A formulação desenvolvida a partir do extrato de P. madagascariensis corresponde a um promissor candidato a antibacteriano tópico com amplo espectro de atividade e elevada potência.Natural products have been used as a valuable source of new lead drugs. The Plectranthus L’Her (Lamiaceae) genus possess a wide diversity of ethnomedicinal uses which indicate the presence of bioactive molecules. Also, innovative methods for natural drug delivery, as phytosome, have showed to be a promising strategy for the improvement of delivery and stability. In this work, three plants from the Plectranthus genus were studied: P. madagascariensis, P. neochilus and P. porcatus. Several extracts were prepared by the combination of extraction methods (infusion, decoction, microwave, ultrasound, maceration and supercritical fluid extraction) with different polarity solvents (water, acetone, methanol and scCO2). Those extracts were profiled by HPLC-DAD and the main components were identified, including polyphenols (caffeic acid, chlorogenic acid and rosmarinic acid), diterpenes (7α-acetoxy,6β-hydroxyroyleanone and coleon U) and flavones (rutina y naringenina). The prepared extracts were screened for their antimicrobial (Gram positive and negative bacteria and yeasts), antioxidant (DPPH radical scavenging activity) and cytotoxic activities (MDA-MB-231 cell line). Extracts from P. madagascariensis (acetone maceration and acetone ultrasound) and P. neochilus (acetone ultrasound) showed antibacterial effects against Gram positive bacteria strains, namely, Bacillus subtilis, Staphylococcus aureus and S. epidermidis and a Gram negative bacteria strain, Klebsiella pneumonia (MIC values 1.95-250 μg/mL). The ultrasound extract of P. madagascariensis prepared with acetone showed potent antibacterial effect against Staphylococcus spp., including a methicillin-resistant strain (MRSA), with MIC values ranging from 1.95 to 7.81 μg/mL. These results validate the traditional uses of such plants as anti-infectious agents. All methanolic extracts showed potent antioxidant effects at 100 ng/mL (60.8-89.0%). The maceration acetone extract from P. madagascariensis showed moderate cytotoxic effects in the MDA-MB-231 breast cancer cell line with IC50 of 64.52 μg/mL. The organic solvent extracts from P. madagascariensis were the most bioactive and thus characterized (identification and quantification) using HPLC-DAD. Furthermore, the compounds were identified by authentic standard overlay: rosmarinic acid, 7α,6β-dihydroxyroyleanone, 7α-acetoxy-6β-hydroxyroyleanone and coleon U. A diterpenic compound was isolated from the ultrasound acetonic extract of P. madagascariensis and spectroscopically characterized (1H- and 13C-NMR) as 7α-formyloxy-6β-hydroxyroyleanone. This was the first time this compound was isolated from this plant. The cytotoxic effect of the identified compounds was evaluated in a battery of cancer cell lines (MDA-MB-231, MCF-7, HCT116, NCI-H460 and MCR-5). The diterpenic compounds showed moderate to potent cytotoxicity in the majority of tested cell lines. A high selectivity for cancer cell lines was observed for 7α,6β-dihydroxyroyleanone and 7α-acetoxy-6β-hydroxyroyleanone with selectivity index of 4.3 and 3.2, respectively. The combination of the observed results and literature data afforded the establishment of new structure-activity relationships of roylenanone abietanic compounds. The relevance of lipophilicity and of the presence of an electron donating group at 6 and/or 7 positions was observed. The antibacterial acetonic ultrasound extract from P. madagascariensis identified in the initial screening was selected for incorporation into a phytosomal formulation and subsequently coated by chitosan. Phytosomes were amorphous, uniform in shape as shown by AFM and SEM, and with an average size of 1082 ± 363 nm and zeta potential of +20.59 ± 12.02 mV. The encapsulation of the antibacterial extract was determined by HPLC (57.7±0.06%) and the chemical interactions between the formulation components was cofirmed by DSC and DRIFTS. Such phytosomes showed a sustained release of the extract 4 and lower skin-like permeation fluxes. An improvement up to a 4-fold factor in the anti-Staphylococci activity (MIC values 0.98-31.25 μg/mL) was observed. The safety of such formulation was verified by in vitro human keratinocytes cytotoxicity assays and by in vivo acute and sub-chronic dermal irritation tests in mice. This study showed the potential of the Plectranthus genus as source of lead antibacterial and antiproliferative agents and validate the ethnomedicinal uses of the studied plants. The isolated abietane diterpenes obtained from P. madagascariensis possess promising selective cytotoxic effects, namely, aginst the lung cancer lines tested. Also, the developed formulation of extract of P. madagascariensis corresponds to a potent topical antibacterial candidate with a broad spectrum of activity