Caracterização mineralógica e geoquímica de perfis lateríticos do Complexo Máfico Ultramáfico de Niquelândia - GO

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A Criação de uma Entidade Quase-Judicial como Órgão de Administração Eleitoral em Angola

Esta tese versa sobre “A criação de um Entidade Quase-Judicial como Órgão de Administração Eleitoral em Angola”. Parte do pressuposto que o direito eleitoral assume uma importância fundamental para uma democracia. O direito eleitoral começa por ter a sua estrutura definida na Constituição. A lei ordinária apenas desenvolve os axiomas constitucionais. Não há um modelo a seguir para aprovar leis eleitorais, nem uma receita a seguir quanto ao seu conteúdo e estrutura. Nenhum país pode exportar o seu quadro legal para outro país, dado que o contexto desempenha um papel importante na aplicação das normas internacionais. A validade dos procedimentos eleitorais assegura a legitimidade imperativa que permite o exercício do poder político. As eleições devem ser compreendidas como abrangendo todos os componentes do ciclo e não apenas o dia da eleição ou a campanha eleitoral. Os órgãos de administração eleitoral (OAE) são instituições importantes para a construção da democracia, uma vez que lidam diretamente com a organização de eleições multipartidárias e indiretamente com a governação e a afirmação do Estado de Direito. O melhor modelo de OAE contribuirá para uma melhor democracia. Em regra, no final do século XX a maioria das novas democracias têm adotado um modelo similar de administração eleitoral: comissões independentes multipartidárias com base permanente. Estas comissões foram concebidas como uma salvaguarda para o exercício do voto numa atmosfera de desconfiança política e de excessos por parte do poder executivo. Nas comissões eleitorais de base partidária, procura-se que os comissários tenham mandatos independentes e não revogáveis. Existe geralmente a possibilidade de recurso contencioso das decisões eleitorais, seja em tribunais especializados, seja nos tribunais comuns. A República de Angola assume-se constitucionalmente como um Estado Democrático de Direito. Nesse sentido, o povo exerce a soberania, de forma indireta através dos seus representantes políticos e direta através do referendo e outras formas de participação, como aliás referem os artigos 3.º e 4.º da CRA. Entendemos que existe um normativo geralmente adequado em relação às eleições, quer pela legislação em vigor, quer pela diferença de órgãos que intervêm nas eleições. Por parte do Executivo temos o Ministério da Administração do Território (MAT), por parte do Poder Judicial temos o Tribunal Constitucional e os tribunais comuns, se for o caso, e ainda temos a Comissão Nacional Eleitoral (CNE) como órgão independente. Contudo, tal não é suficiente para garantir a credibilidade das eleições. Há que procurar um modelo mais aperfeiçoado e que garanta a verdade eleitoral. Uma mistura de autoridade centralizada e de gestão descentralizada parece ser a mais promissora para uma consolidação democrática bem-sucedida em Angola. Daí que desenvolvamos uma proposta alternativa concreta

O sistema eleitoral angolano: a consolidação democrática através da garantia de eleições livres

Este trabalho versa sobre o sistema eleitoral Angolano e o seu contributo para a instauração de uma democracia representativa em Angola. Numa primeira fase são analisados os conceitos básicos, designadamente, democracia e participação política. E entendendo que uma cidadania ativa e participativa é fundamental para a Democracia. Numa segunda fase são vistos os principais sistemas eleitorais existentes nas democracias modernas, verificando a sua estrutura, aplicação e implicações. Seguidamente, é descrita a situação angolana, começando pela Constituição e os seus órgãos democráticos e detalhando o sistema eleitoral angolano. Finalmente, conclui-se pela adequação e contributo positivo que o sistema eleitoral angolano, atualmente em vigor, representa para a implantação de uma democracia moderna em Angola, destacando em especial, o papel do Tribunal Constitucional e da Comissão Nacional Eleitoral

Neural stem cells and cannabinoids in the spotlight as potential therapy for epilepsy

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).Epilepsy is one of the most common brain diseases worldwide, having a huge burden in society. The main hallmark of epilepsy is the occurrence of spontaneous recurrent seizures, having a tremendous impact on the lives of the patients and of their relatives. Currently, the therapeutic strategies are mostly based on the use of antiepileptic drugs, and because several types of epilepsies are of unknown origin, a high percentage of patients are resistant to the available pharmacotherapy, continuing to experience seizures overtime. Therefore, the search for new drugs and therapeutic targets is highly important. One key aspect to be targeted is the aberrant adult hippocampal neurogenesis (AHN) derived from Neural Stem Cells (NSCs). Indeed, targeting seizure-induced AHN may reduce recurrent seizures and shed some light on the mechanisms of disease. The endocannabinoid system is a known modulator of AHN, and due to the known endogenous antiepileptic properties, it is an interesting candidate for the generation of new antiepileptic drugs. However, further studies and clinical trials are required to investigate the putative mechanisms by which cannabinoids can be used to treat epilepsy. In this manuscript, we will review how cannabinoid-induced modulation of NSCs may promote neural plasticity and whether these drugs can be used as putative antiepileptic treatment.This work was supported by IF/01227/2015 and UID/BIM/50005/2019, projeto financiado pela Fundação para a Ciência e a Tecnologia (FCT)/Ministério da Ciência, Tecnologia e Ensino Superior (MCTES) através de Fundos do Orçamento de Estado. D.M.L. (PD/BD/141784/2018) and L.R.-R. (PD/BD/150344/2019) were in receipt of a fellowship from FCT. The authors are in hold of a H2020 Twinning Action from EU (EpiEpiNet).info:eu-repo/semantics/publishedVersio

Cloud-Based Implementation of an Automatic Coverage Estimation Methodology for Self-Organising Network

UIDB/EEA/50008/2020One of the main concerns of telecommunications operators is related to network coverage. A weak coverage can lead to a performance decrease, not only in the user experience, when using the operators' services, such as multimedia streaming, but also in the overall Quality of Service. This paper presents a novel cloud-based framework of a semi-empirical propagation model that estimates the coverage in a precise way. The novelty of this model is that it is automatically calibrated by using drive test measurements, terrain morphology, buildings in the area, configurations of the network itself and key performance indicators, automatically extracted from the operator's network. Requirements and use cases are presented as motivations for this methodology. The results achieve an accuracy of about 5 dB, allowing operators to obtain accurate neighbour lists, optimise network planning and automate certain actions on the network by enabling the Self-Organising Network concept. The cloud implementation enables a fast and easy integration with other network management and monitoring tools, such as the Metric platform, optimising operators' resource usage recurring to elastic resources on-demand when needed. This implementation was integrated into the Metric platform, which is currently available to be used by several operators.publishersversionpublishe

Comparative life cycle assessment of first- and second-generation ethanol from sugarcane in Brazil

ABSTRACT: Purpose: The use of bagasse and trash from sugarcane fields in ethanol production is supposed to increase the ethanol yield per hectare, to reduce the energy demand, greenhouse gas emissions, and other environmental impacts. In this article, different technological options of ethanol production are investigated and quantified looking at potential environmental impacts. The first generation ethanol from sugarcane is compared to stand-alone second-generation ethanol as well as an integrated first- and second-generation ethanol production. Methods: The method applied for this life cycle assessment follows the ISO standards 14040/44. The data used in this life cycle assessment is mainly derived from process simulation, literature, and primary data collection. Background data was taken from databases such as GaBi and ecoinvent. The life cycle impact assessment follows the default methods at midpoint level recommended by the International Reference Life Cycle Data System. The calculations were performed using the GaBi 7 life cycle assessment software. It is assumed that 50% of sugarcane trash is recovered and used for second-generation ethanol production, whereas the other 50% remain in the field to maintain soil fertility and to prevent soil erosion. In the case of first-generation ethanol, the same amount of trash is used for energy generation. Results and discussion: The results of the life cycle impact assessment show that, compared to first-generation ethanol, secondgeneration ethanol from sugarcane in Brazil allows significant reductions in all investigated impact categories except resource depletion. Resource depletion, however, is strongly influenced by the demand for ammonium phosphate which is needed for inoculum preparation. Integrated first- and second-generation ethanol production also allows reductions in most of the environmental impacts except for global warming, photochemical ozone depletion, and resource depletion. The yield of ethanol per hectare increases since bagasse and trash are used for the production of second-generation ethanol. Consequently, the results show that agricultural land occupation is reduced for integrated first- and second-generation ethanol by approximately 11%, whereas second-generation ethanol allows reduction of land use by approximately a factor of 30. Conclusions: The use of bagasse and trash for ethanol production allows both the reduction of several environmental impacts and land use, in particular, because impacts caused by sugarcane cultivation are avoided. For the integrated first- and second generation ethanol scenario, it is important to further reduce the total energy demand in order to achieve self-sufficiency for the plant energy and to avoid additional emissions from burning fossil fuels.info:eu-repo/semantics/publishedVersio

Life cycle assessment of advanced bioethanol production from pulp and paper sludge

This work evaluates the environmental performance of using pulp and paper sludge as feedstock for the production of second generation ethanol. An ethanol plant for converting 5400 tons of dry sludge/year was modelled and evaluated using a cradle-to-gate life cycle assessment approach. The sludge is a burden for pulp and paper mills that is mainly disposed in landfilling. The studied system allows for the valorisation of the waste, which due to its high polysaccharide content is a valuable feedstock for bioethanol production. Eleven impact categories were analysed and the results showed that enzymatic hydrolysis and neutralisation of the CaCO3 are the environmental hotspots of the system contributing up to 85% to the overall impacts. Two optimisation scenarios were evaluated: (1) using a reduced HCl amount in the neutralisation stage and (2) co-fermentation of xylose and glucose, for maximal ethanol yield. Both scenarios displayed significant environmental impact improvements

Modeling Rett syndrome with human patient-specific forebrain organoids

Copyright © 2020 Gomes, Fernandes, Vaz, Silva, Bekman, Xapelli, Duarte, Ghazvini, Gribnau, Muotri, Trujillo, Sebastião, Cabral and Diogo. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Engineering brain organoids from human induced pluripotent stem cells (hiPSCs) is a powerful tool for modeling brain development and neurological disorders. Rett syndrome (RTT), a rare neurodevelopmental disorder, can greatly benefit from this technology, since it affects multiple neuronal subtypes in forebrain sub-regions. We have established dorsal and ventral forebrain organoids from control and RTT patient-specific hiPSCs recapitulating 3D organization and functional network complexity. Our data revealed a premature development of the deep-cortical layer, associated to the formation of TBR1 and CTIP2 neurons, and a lower expression of neural progenitor/proliferative cells in female RTT dorsal organoids. Moreover, calcium imaging and electrophysiology analysis demonstrated functional defects of RTT neurons. Additionally, assembly of RTT dorsal and ventral organoids revealed impairments of interneuron's migration. Overall, our models provide a better understanding of RTT during early stages of neural development, demonstrating a great potential for personalized diagnosis and drug screening.We also acknowledge financial support from Fundação para a Ciência e a Tecnologia (FCT), Portugal, through iBB, Institute for Bioengineering and Biosciences (UIDB/04565/2020) and from Programa Operacional Regional de Lisboa 2020 (Project No. 007317). AG was supported by FCT (PD/BD/128373/2017).info:eu-repo/semantics/publishedVersio