143 research outputs found
REAP, a project for PET and can
In a moment of change, with an impulse from the pandemic that hit the world, the pursuit of the Sustainable Development Goals has become a clear necessity towards a more sustainable world, with less inequalities and a basis for the upbringing of future generations. SDG Goal 12 Sustainable Consumption and Production, 13 - Climate Action - and 14 - Life below water - are clearly linked to plastic and metal consumption and production. Also, Goal 10 - Reduced inequalities - plays its paper in this field. Not only does plastic and metal production, consumption and use need to be reformed, but also producers need to bridge inequalities and reuse, recycle and introduce circular economies in their own countries, not inducing mass imposition of waste in poorer economies. With this in mind, at the University of Aveiro, the REAP Project (Recycling of PET and Aluminium Packages) is being implemented, together with a Norwegian partner, with vast experience in the plastic waste sector. This project will help create the idea of PET and aluminium impact from a tax on these packages inside campi walls and a tax return after adequate deposition. Tracking these numbers and promoting research in the area of PET and aluminium reuse are a further input towards the implementation of SDGs.The paper will explain the project, its goals and ambitions.Keyword: PET, Can, SDG Goals, circular econom
Archaeological and chemical investigation on the high imperial mosaic floor mortars of the domus integrated in the museum of archaeology D. Diogo de Sousa, Braga, Portugal
This paper intends to characterize the floor mortar layers (nucleus, rudus and statumen) of the high imperial mosaics of the domus integrated in the Museum of Archeology D. Diogo de Sousa, the oldest roman housing testimonies known in Braga, Portugal. It offers an important archaeological and historical contextualization and first chemical characterization attempt on the mortars. The study of 13 mortar samples was carried out at a chemical level through X-ray fluorescence spectroscopy (XRF). All samples presented low lime content when compared to similar studies. A high chemical similarity between nucleus mortars (opus signinum) and chemical composition differences between rudus and statumen mortars was determined, confirmed by statistical analyses. Their composition was distinctly related to the stratigraphic position of each floor mortar layer, following Vitruvius’ model, and to the external conditions and treatments (e.g., capillary rise with soluble salts and application of chemical treatments), to which they were submitted.This research was funded by GeoBioTec Research Centre (UIDB/04035/2020), funded
by FCT—Fundação para a Ciência e a Tecnologia, FEDER funds through the Operational Program
Competitiveness Factors COMPETE and by national funds (OE), through FCT, in the scope of the
framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016,
of 29 August, changed by Law 57/2017, of 19 July
Tratamento da Perturbação Depressiva Major com Psicadélicos: Uma Potencial Aplicação Terapêutica para a Psilocibina?
Argamassas de cal com pozolanas para revestimento de paredes antigas
Doutoramento em Engenharia CivilO presente trabalho tem como base o estudo de argamassas a aplicar na conservação de edifícios antigos, incidindo sobre argamassas contendo pozolanas e com cal aérea como ligante. Foi feito um levantamento dos materiais pozolânicos existentes, assim como das suas características. A reacção pozolânica associada a este tipo de argamassas foi estudada e explicitada. O estudo de argamassas antigas com pozolanas englobou pesquisa bibliográfica, assim como a recolha, análise e ensaio de argamassas provenientes de várias épocas, locais e tipos de edifícios. Foram analisadas as características das argamassas antigas a partir dos resultados obtidos. A elaboração de argamassas de cal aérea e pozolana partiu de um estudo prévio, para aferir as melhores composições e avaliar a influência de diferentes condicionamentos. Foram escolhidos e analisados diversos materiais potencialmente pozolânicos e foram formuladas argamassas com esses materiais. Um conjunto de ensaios mecânicos e físicos foi aplicado às argamassas elaboradas, permitindo estabelecer a sua adequação para aplicação em edifícios antigos. Finalmente foram efectuadas aplicações em muretes exteriores, painéis e num edifício antigo.The current work is based on the study of mortars to be applied in the conservation of ancient buildings, focusing on mortars containing pozolanas and aerial lime as a binder. A survey of the existing pozzolanic materials and their characteristics was undertaken. Pozzolanic reaction, associated with these mortars was studied and explained. The study of ancient mortars encompassed bibliographic research, withdrawal, analysis and testing of mortar samples from various periods, locations and types of buildings. The characteristics of ancient mortars were analysed based on the obtained results. A previous study was performed in which mortars with aerial lime and pozzolans were prepared, the best compositions were established and the influence of different curing conditions was evaluated. Several materials with a pozzolanic potential were chosen and analysed and mortars were formulated with these materials. A set of mechanical and physical tests was performed on the executed mortars, allowing for an assessment of their adequacy for application on old masonry. At last, applications on exterior walls, on panels and on an ancient building were carried out
Neurotransmissores e drogas: alterações e implicações clínicas
Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências FarmacêuticasOs neurotransmissores e neuromoduladores, são moléculas do sistema nervoso que desempenham um papel fundamental na comunicação intercelular. Quando estimulados os neurónios libertam estas moléculas que posteriormente vão atuar em recetores pré e/ou pós-sinápticos, desencadeando uma resposta biológica.
A comunicação intercelular no sistema nervoso central exige um controlo rigoroso da duração e intensidade da ação de um neurotransmissor num determinado alvo. Os neurotransmissores podem ser excitatórios ou inibitórios dependendo do recetor que é ativado.
As drogas de abuso, como o álcool, as metanfetaminas, a cocaína, a heroína, o LDS e a cannabis, influenciam a comunicação entre as células nervosas ao alterar a forma como os neurotransmissores transmitem sinais (informação) de neurónio para neurónio. As drogas possuem diversas ações psicotrópicas que vão desde a supressão de sensações negativas à potenciação de emoções positivas. Além disso, estão associadas a diferentes graus de toxidade, bem como a efeitos adversos graves, a nível mental e físico, e dependência. Grande parte da ação das drogas de abuso deve-se a alterações na transmissão sináptica. Neurotransmitters and neuromodulators are molecules that are part of the nervous system and play a fundamental role in the intercellular communication. When stimulated, the neurons release these molecules that will then act on pre or post-synaptic receptors, triggering a biological response.
The intercellular communication in the central nervous system requires a rigorous control on the duration an intensity of a neurotransmitter action on a determined target. Neurotransmitters may be excitatory or inhibitory depending on the receptor that is activated.
Drug abuse, such as alcohol, methamphetamines, cocaine, heroin, LSD and cannabis influence the communication between nervous cells by altering the way neurotransmitters transmit signals (information) between neurons. Drugs have different psychotropic actions, from the suppression of negative sensations to the potentiation of positive emotions. Besides, they are associated to different levels of toxicity as well as to severe adverse physical and mental effects and dependency. A major part of the abuse drugs action is due to alterations in the synaptic transmission
Neurotransmissores e drogas: alterações e implicações clínicas
Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências FarmacêuticasOs neurotransmissores e neuromoduladores, são moléculas do sistema nervoso que desempenham um papel fundamental na comunicação intercelular. Quando estimulados os neurónios libertam estas moléculas que posteriormente vão atuar em recetores pré e/ou pós-sinápticos, desencadeando uma resposta biológica.
A comunicação intercelular no sistema nervoso central exige um controlo rigoroso da duração e intensidade da ação de um neurotransmissor num determinado alvo. Os neurotransmissores podem ser excitatórios ou inibitórios dependendo do recetor que é ativado.
As drogas de abuso, como o álcool, as metanfetaminas, a cocaína, a heroína, o LDS e a cannabis, influenciam a comunicação entre as células nervosas ao alterar a forma como os neurotransmissores transmitem sinais (informação) de neurónio para neurónio. As drogas possuem diversas ações psicotrópicas que vão desde a supressão de sensações negativas à potenciação de emoções positivas. Além disso, estão associadas a diferentes graus de toxidade, bem como a efeitos adversos graves, a nível mental e físico, e dependência. Grande parte da ação das drogas de abuso deve-se a alterações na transmissão sináptica. Neurotransmitters and neuromodulators are molecules that are part of the nervous system and play a fundamental role in the intercellular communication. When stimulated, the neurons release these molecules that will then act on pre or post-synaptic receptors, triggering a biological response.
The intercellular communication in the central nervous system requires a rigorous control on the duration an intensity of a neurotransmitter action on a determined target. Neurotransmitters may be excitatory or inhibitory depending on the receptor that is activated.
Drug abuse, such as alcohol, methamphetamines, cocaine, heroin, LSD and cannabis influence the communication between nervous cells by altering the way neurotransmitters transmit signals (information) between neurons. Drugs have different psychotropic actions, from the suppression of negative sensations to the potentiation of positive emotions. Besides, they are associated to different levels of toxicity as well as to severe adverse physical and mental effects and dependency. A major part of the abuse drugs action is due to alterations in the synaptic transmission
A Systematic Review and Meta-Analysis
Background: Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder manifesting as lifelong deficits in social communication and interaction, as well as restricted repetitive behaviors, interests and activities. While there are no specific pharmacological or other physical treatments for autism, in recent years repetitive Transcranial Magnetic Stimulation (rTMS), a technique for non-invasive neuromodulation, has attracted interest due to potential therapeutic value. Here we report the results of a systematic literature review and meta-analysis on the use of rTMS to treat ASD. Methods: We performed a systematic literature search on PubMed, Web of Science, Science Direct, Bielefeld Academic Search, and Educational Resources Information Clearinghouse. Search terms reflected diagnoses and treatment modalities of interest. Studies reporting use of rTMS to treat core ASD or cognitive symptoms in ASD were eligible. Two researchers performed article selection and data extraction independently, according to PRISMA guidelines. Changes in ASD clinical scores or in cognitive performance were the main outcomes. Random effects meta-analysis models were performed. Results: We found 23 eligible reports, comprising 4 case-reports, 7 non-controlled clinical trials, and 12 controlled clinical trials, comparing the effects of real TMS with waiting-list controls (n = 6) or sham-treatment (n = 6). Meta-analyses showed a significant, but moderate, effect on repetitive and stereotyped behaviors, social behavior, and number of errors in executive function tasks, but not other outcomes. Most studies had a moderate to high risk of bias, mostly due to lack of subject- and evaluator-blinding to treatment allocation. Only 5 studies reported stability of these gains for periods of up 6 months, with descriptions that improvements were sustained over time. Conclusions: Existing evidence supports that TMS could be useful to treat some dimensions of ASD. However, such evidence must be regarded with care, as most studies did not adequately control for placebo effects. Moreover, little is known regarding the most effective stimulation parameters, targets, and schedules. There is an urgent need for further randomized, double-blind, sham-controlled trials, with adequate follow-up periods, to test the efficacy of transcranial magnetic stimulation to treat these disorders. Available evidence must be regarded as preliminary and insufficient, at present, to support offering TMS to treat ASD.publishersversionpublishe
Papel de nano-aditivos na funcionalização de argamassas
A manutenção da qualidade do ar no interior dos edifícios é um dos aspetos
mais relevantes da construção sustentável e tem forte impacto no nível de conforto dos
utilizadores. A introdução de nano-aditivos em materiais de construção permite modificar propriedades fundamentais destes materiais convencionais, com o objetivo de proporcionar novas funcionalidades. Neste trabalho apresentam-se os resultados obtidos
com o desenvolvimento de argamassas funcionais que pretendem melhorar a qualidade do ar interior e contribuir para a poupança energética dos edifícios. As formulações foram optimizadas com vista à sua aplicação em construção nova ou reabilitação
New natural hydraulic lime mortars – Physical and microstructural properties in different curing conditions
Construction and Building Materials 54 (2014) 378–384The new version of EN 459-1 standard for building limes redefined the classes of hydraulic limes and
made the producers reformulate or reclassify their natural hydraulic limes.
This work evaluates the mechanical, physical and microstructural behavior of mortars formulated with
a recently produced natural hydraulic lime NHL3.5 that conforms to EN 459-1, submitted to natural marine
environment, humid and standardized conditions, and also the benefits and drawbacks of adding
metakaolin in partial replacement of lime.
Mortars with NHL3.5 present positive results at young ages. The metakaolin addition increases strength
while decreasing the capillary water coefficient. The behavior in an aggressive marine environment
seems promising
Mechanical and mineralogical properties of natural hydraulic lime-metakaolin mortars in different curing conditions
Construction and Building Materials 51 (2014) 287–294This paper investigates the mechanical and mineralogical characteristics of natural hydraulic lime
NHL3.5 (NHL) mortars with different% of lime replacement by metakaolin (MK) under different laboratory
and natural marine curing conditions.
Tests were conducted at different curing ages, using compressive and flexural strength tests and thermogravimetric
and X-ray diffraction techniques.
NHL mortars cured at high humidity levels in natural and artificial environments present interesting
results and some could be used in old masonries repair.
The incorporation of MK improves the NHL mortars strength, being this increase mostly associated to
the pozzolanic reaction
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