Elasmobrânquios do Meso-Cenozóico Brasileiro

On tentera dans ce travail de donner un accent plus actuel à la position taxonomique des sélaciens du Mesozoique et du cénozoique à partir d'une nouvelle classification proposée par divers auteurs. On traitera également de l'état des conaissances actuelles de ce groupe au Brésil, en fournissant um bref historique et en essayant de donner une classification plus moderne pour les taxons proposés pour les dépots fossilifères brésiliens.No presente trabalho, tentaremos dar um enfoque mais atual na posição taxonómica dos seláquios do Mesozoico e Cenozóico com base na nova classificação proposta por varios autores. Trataremos também do estado de conhecimento atual des te grupo no Brasil, dando um breve histórico e procurando dar uma classificação geral mais moderna para os taxa propostos para os depósitos fossilíferos brasileiros

Ignacio Aureliano Machado Brito (1938-2001)

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Money supply and the credit market in early modern economies : the case of eighteenth-century Lisbon

In this paper, we address the partial equilibrium functioning of the shortterm credit market in the Eighteenth-century Lisbon and its response to three major events: massive gold inflows from Brazil, a catastrophic destruction of capital caused by the 1755 earthquake and the enactment of a 5% legal ceiling on interest rates 1757. We build a time series for the market interest rate, and a regression shows money stock and real estates as two significant variables. Interest rates were affected negatively by the former and positively by the latter. We conclude that changes in the money stock tended to operate through the supply of loanable funds. The wealth effect, measured by the stock of real estate, operated over demand and tended to be the most significant effect among several other possible countervailing effects (e.g., the impact of wealth effects on supply, the informational effects of collaterals). The inflow of gold clearly generated a liquidity which by itself explained the downward trend in interest rates up until around 1780. However, the huge variations experienced by the stock of capital after the earthquake also explains the steadiness of interest rates in a period when the inflow of money started to recede. For the whole period during which the 5 % ceiling on interest rates was in force we do not find any evidence to confirm the existence of disequilibrium credit rationing: the notional interest rate predicted by our model was very close to the 5% legal ceiling

Spatial clustering of molecular dynamics trajectories in protein unfolding simulations

Molecular dynamics simulations is a valuable tool to study protein unfolding in silico. Analyzing the relative spatial position of the residues during the simulation may indicate which residues are essential in determining the protein structure. We present a method, inspired by a popular data mining technique called Frequent Itemset Mining, that clusters sets of amino acid residues with a synchronized trajectory during the unfolding process. The proposed approach has several advantages over traditional hierarchical clustering.The authors acknowledge the support of the "Fundacao para a Ciencia e Tecnologia,Portugal, and the program FEDER, through grant PTDC/BIA-PRO/72838/2006 (to PJA and RMMB) and the Fellowships SFRH/BPD/42003/2007(to PGF) and SFRH/BD/16888/2004 (to CGS). We thank the Center for Computational Physics, Departamento de Fisica, Universidade de Coimbra, for the computer resources provided for the MD simulations

Mining approximate motifs in time series

The problem of discovering previously unknown frequent patterns in time series, also called motifs, has been recently introduced. A motif is a subseries pattern that appears a significant number of times. Results demonstrate that motifs may provide valuable insights about the data and have a wide range of applications in data mining tasks. The main motivation for this study was the need to mine time series data from protein folding/unfolding simulations. We propose an algorithm that extracts approximate motifs, i.e. motifs that capture portions of time series with a similar and eventually symmetric behaviour. Preliminary results on the analysis of protein unfolding data support this proposal as a valuable tool. Additional experiments demonstrate that the application of utility of our algorithm is not limited to this particular problem. Rather it can be an interesting tool to be applied in many real world problems.Fundação para a Ciência e a Tecnologia (FCT).Fundo Europeu de Desenvolvimento Regional (FEDER) - POCTI/BME/49583/2002; SFRH/BD/13462/2003; SFRH/BD/16888/2004

Modelização de separações por membrana através de métodos de refinamento de malha

Aplicou-se um modelo que conjuga a polarização da concentração e o transporte numa membrana para simular a ultrafiltração de soluções aquosas de PEG-3400. O problema incorpora o modelo de fricção binária desenvolvido a partir de uma modificação da equação de Maxwell-Stefan-Lightfoot. Desenvolveu-se um método numérico adaptativo eficiente para resolver simultaneamente as duas partes do modelo (camada de polarização e membrana). A resolução numérica do sistema algébrico-diferencial permitiu a ilustração adequada do fenómeno de rejeição aparente de soluto (em soluções aquosas de PEG-3400) assim como da queda de pressão em função do fluxo. Por outro lado, possibilitou a previsão adequada da influência de parâmetros físico-químicos e das condições de operação nesses fenómenos de rejeição, para além da correcta formação dos perfis de concentração e de fluxo quer na zona da camada de polarização como da membrana. A comparação com valores experimentais de ultrafiltração possibilita a validação do modelo no caso específico das soluções de PEG-3400. Os resultados de simulação dependem significativamente das características de resistência, Rm, da membrana que manifestam uma grande variabilidade de ensaio para ensaio e que influenciam o valor do coeficiente de equilíbrio, Keq

Performance analysis and optimization of a N-class bipolar network

A wireless network with unsaturated traffic and N classes of users sharing a channel under random access is analyzed here. Necessary and sufficient conditions for the network stability are derived, along with simple closed formulas for the stationary packet transmission success probabilities and mean packet delays for all classes under stability conditions. We also show, through simple and elegant expressions, that the channel sharing mechanism in the investigated scenario can be seen as a process of partitioning a well-defined quantity into portions, each portion assigned to each user class, the size of which determined by system parameters and performance metrics of that user class. Using the derived expressions, optimization problems are then formulated and solved to minimize the mean packet delay and to maximize the channel throughput per unit of area. These results indicate that the proposed analysis is capable of assessing the trade-off involved in radio-resource management when different classes of users are considered7135118135132CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP311485/2015-4não tem2017/21347-0This work was supported in part by the Foundation for Research Support of the State of São Paulo under Grant 2017/21347-0, in part by the Brazilian National Council for Scientific and Technological Development under Grant 311485/2015-4, in part by the Academy of Finland via the ee-IoT Project under Grant 319009, in part by the FIREMAN Consortium under Grant CHIST-ERA 326270, in part by the EnergyNet Research Fellowship under Grant 321265 and Grant 328869, in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior–Brazil (CAPES) under Grant 001, in part by the RNP, with resources from MCTIC, under the Radiocommunication Reference Center (CRR) Project of the National Institute of Telecommunications (Inatel), Brazil, under Grant 01250.075413/2018-0

Gasification of Solid Recovered Fuels with Variable Fractions of Polymeric Materials †

Funding Information: This work was funded by FCT–Fundação para a Ciência e a Tecnologia, I.P. (grant no. SFRH/BD/111956/2015), co-financed by Programa Operacional Potencial Humano and União Europeia-Fundo Social Europeu, by the project POCI-01-0145-FEDER-024020 (RDFGAS–Energy recovery of refuse-derived fuel and dehydrated sludge), co-financed by COMPETE 2020–Programa Operacional Competitividade e Internacionalização, Portugal 2020 and União Europeia through FEDER, and also by FCT–Fundação para a Ciência e a Tecnologia, I.P., within the R&D Units Project Scope UIDP/04077/2020 (MEtRICS) and the project UIDB/05064/2020 (VALORIZA—Research Centre for Endogenous Resource Valorization). Publisher Copyright: © 2022 by the authors.Gasification is a promising thermochemical technology used to convert waste materials into energy with the introduction of low amounts of an oxidant agent, therefore producing an environmental impact that is lower when compared to incineration and landfilling. Moreover, gasification allows a sustainable management of wastes and reduces the use of fossil fuels responsible for the increment of greenhouse gases. This work aimed to perform gasification tests with solid recovered fuels (SRF) containing organic fractions mainly retrieved from construction and demolition wastes to assess the potential for energy conversion. Tests were conducted in a pilot-scale downdraft gasifier (maximum feedstock input of 22 kg/h) at c.a. 800 °C, using SRF samples containing different proportions of polymeric wastes ranging between 0 and 20 wt %. Gas and chars obtained as by-products were analysed to evaluate their properties and to establish valid pathways for their valorisation. The addition of polymeric wastes reduced char production but rose both tar and HCl concentrations in the gas. The SRF with 10 wt % of polymeric wastes generated the best results, producing the highest calorific value for the gas (3.5 MJ/Nm3) and the highest cold-gas efficiency (45%). Possible char applications include their use as catalysts for tar decomposition, or as an additive in construction materials. Gasification can therefore be considered a valid solution for the energetic valorisation of these SRFs.publishersversionpublishe