A Framework for the Design and Implementation of Learning Objects: a Competence-based Approach

This paper presents a framework for the design and implementation of learning objects using a competence-based approach. This framework is illustrated by the development of a standalone Windows application (Trilho GOA) whose primary purpose is to create standardized pedagogical contents trough the aggregation and standardization of instructional resources in several formats that can be used later on a Learning Management System (LMS) supporting SCORM 1.2. The paper contains a brief introduction to the developed software, its system architecture, main features and several pedagogical advantages for its users

Vortex transmutation

Using group theory arguments and numerical simulations, we demonstrate the possibility of changing the vorticity or topological charge of an individual vortex by means of the action of a system possessing a discrete rotational symmetry of finite order. We establish on theoretical grounds a "transmutation pass rule'' determining the conditions for this phenomenon to occur and numerically analize it in the context of two-dimensional optical lattices or, equivalently, in that of Bose-Einstein condensates in periodic potentials.Comment: 4 pages, 4 figure

Concepção de roteiros de formação para a oferta formativa do Programa Aveiro Norte

Este artigo tem por objectivo a apresentação de um roteiro de formação baseado no contexto de estudo acompanhado que recorre à conceptualização de um roteiro de formação/roteiro de aula que identifica os vários módulos formativos ou disciplinas de ensino, organizados através de marcos de aprendizagem indexados aos conteúdos de formação e ensino propostos com o intuito de que estes sejam aprendidos com maior sucesso

Email spam detection : a symbiotic feature selection approach fostered by evolutionary computation

Post-print version (prior to journal publication)The electronic mail (email) is nowadays an essential communication service being widely used by most Internet users. One of the main problems affecting this service is the proliferation of unsolicited messages (usually denoted by spam) which, despite the efforts made by the research community, still remains as an inherent problem affecting this Internet service. In this perspective, this work proposes and explores the concept of a novel symbiotic feature selection approach allowing the exchange of relevant features among distinct collaborating users, in order to improve the behavior of anti-spam filters. For such purpose, several Evolutionary Algorithms (EA) are explored as optimization engines able to enhance feature selection strategies within the anti-spam area. The proposed mechanisms are tested using a realistic incremental retraining evaluation procedure and resorting to a novel corpus based on the well-known Enron datasets mixed with recent spam data. The obtained results show that the proposed symbiotic approach is competitive also having the advantage of preserving end-users privacy.The work of P. Cortez and P. Sousa was funded by FEDER, through the program COMPETE and the Portuguese Foundation for Science and Technology (FCT), within the project FCOMP-01-0124-FEDER-022674

First evidence of ants (Hymenoptera, Formicidae) in the early Pleistocene of Madeira Island (Portugal)

To be successfully established on oceanic islands, native ants (Hymenoptera: Formicidae) have to migrate from the mainland or from nearby islands, crossing the ocean barriers, to find a suitable habitat. Despite the general interest on oceanic islands biotas, nothing is known about the deep-time migration and settling of native ants in these insular ecosystems. Palaeoentomological studies on oceanic islands that could provide palaeobiological information on Formicidae are scarce. Here, we describe and illustrate the first fossil of an ant from the Macaronesian archipelagos (Atlantic Ocean), based on a partial forewing found within 1.3 Ma (Calabrian, Pleistocene) lacustrine sediments from Madeira Island, Portugal. Although unidentifiable beyond the family level, this fossil record provides a minimum age for the presence of ants in the Madeira archipelago. Palaeoecologically, this record indicates the presence of suitable habitats for ants during the early Pleistocene.info:eu-repo/semantics/publishedVersio

Material compósito de granulado de borracha de pneus usados reciclado numa matriz polimérica

A presente invenção apresenta uma solução que incorpora e melhora a adesão entre o granulado de borracha de pneu usado e a matriz polimérica, pela adição de um agente compatibilizador que para além de compatibilizar os materiais, promove a homogeneidade da mistura e consequentemente obtém-se um material com boas propriedades mecânicas e com bom aspecto superficial. A presente invenção consiste na apresentação de novas formulações de materiais que incorporam borracha de pneu usado em matrizes poliméricas termoplásticas utilizando um agente compatibilizador. Desta mistura obtêm-se produtos com composição de borracha de pneu usado com uma matriz polimérica, recorrendo a aditivos para melhorar as propriedades finais do compósito. O custo é primordial para competir com produtos feitos de matérias virgens e como tal, este processo visa reduzir o custo do produto bem como a quantidade relativa da matéria virgem utilizada e o reaproveitamento da borracha reciclada

Benchmarking do mercado de gestão florestal no Brasil

Orientador : Prof. Dr. João Batista Padilha JuniorMonografia (especialização) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Curso de MBA em AgronegócioInclui referênciasResumo : O presente trabalho aborda os diferentes arranjos institucionais aplicados à gestão de ativos florestais no Brasil, enquanto modalidade de investimento traduzido pela formação/aquisição e gestão de um recurso florestal, com a finalidade de produzir um retorno financeiro. O primeiro investimento institucional registrado na área florestal ocorreu nos Estados Unidos em 1982, a partir daí vários fatores alimentaram o crescimento do universo de investimentos Timberland nos EUA. Com a maioria das figuras institucionais derivadas dos arranjos sociais e financeiros norte-americanos, procura-se aqui, estabelecer a correlação com as figuras jurídicas nacionais e suas respectivas adaptações. Da mesma forma, buscou-se ao longo deste estudo, pela aplicação da técnica do benchmarking, a identificação de uma linha de base para estabelecimento de uma média nacional de precificação sobre a referida modalidade de investimento, no tocante à gestão desse gênero de ativos. Para tanto, realizou-se uma amostragem representativa do universo Timberland nacional, para 12 ativos que, somados, ultrapassam o meio milhão de hectares (504 mil hectares), tendo sido os mesmos analisados e comparados, vis-à-vis, em todas as suas estruturas físicas e financeiras. Desse modo, tornou-se possível inferir que o mercado nacional dos referidos ativos, ainda não se encontra estruturado o suficiente para estabelecimento de cotações médias para as práticas de gestão analisadas, quer seja pela imaturidade da modalidade, quer seja pelas características continentais do país, ainda detentor de regiões remotas denominadas de novas fronteiras produtivas

A prediction model based on data mining to forecast the expectations of passing from a college student

The present work has as objective to apply data mining techniques to develop a predictive model to forecast the chance of passing that will have a college student at the time of enrolling in a particular subject. Given that the academic record of the student can be known, and based on that information, we propose an Artificial Neural Network (ANN) that allows, using various configurations, to predict and assess our goal. The model has been applied to a compulsory subject of higher education of a University and given the results obtained. This model can be applied to any other subject analogous with satisfactory results

Obtención de biomasa de microalga Chlorella vulgaris en un banco de prueba de fotobiorreactores de columna de burbujeo

Dada la agudización de la situación socioeconómica y medioambiental que se enfrenta en la actualidad, los investigadores buscan nuevas alternativas para sustituir el combustible fósil convencional, siendo una salida, los biocombustibles obtenidos a partir de microalgas. El objetivo de esta investigación fue la obtención de biomasa en un banco de prueba de fotobiorreactores de columna de burbujeo, utilizando una cepa de Chlorella vulgaris en medio Bristol. Se dimensionó el fotobiorreactor y se evaluó la influencia de las variables pH y concentración de nitrógeno, con y sin presencia de oligoelementos, sobre la productividaddel crecimiento de la biomasa de microalgas. Seencontró que en el intervalo estudiado (pH entre 6 y 8 y concentración de NaNO3 entre 0,5 y 1 g/L) estas variables no tienen un efecto significativo en el crecimiento, mientras que la presencia de oligoelementos favorece este

Characterization of Braun's lipoprotein and determination of its attachment sites to peptidoglycan by 252Cf-PD and MALDI time-of-flight mass spectrometry

A strategy for the characterization of bacterial lipoprotein-in this case Braun's lipoprotein (an outer membrane 7-ku lipoprotein) isolated from Escherichia coli —is described by time-of-flight mass spectrometric (TOF/MS) techniques [252Cf plasma desorption (PD) TOF/MS and matrix-assisted laser desorption-ionization (MALDI) TOF/MS]. Covalent linkage of lipid at the N-terminal cysteine (posttranslationally modified to a S-[2,3-bis(acyloxy)-propyl]-N-acylcysteine) and, therefore, strict insolubility in aqueous solution constitute common features for this class of proteins. Relative molecular mass determination of the major molecular species of Braun's lipoprotein was obtained by selection of an appropriate mixture of organic solvents compatible with matrix/support materials useful for the mass spectrometric techniques applied. Minor components of this lipoprotein that differ only in the fatty acid composition of the lipid anchor were detected by PD TOF/MS after enzymatic release of the extremely hydrophobic N-terminal amino acid followed by selective extraction with chloroform. Part of the primary sequence of this lipoprotein was confirmed based on peptide fragment ions observed in the positive ion PD mass spectra of cyanogen bromide-generated peptide fragments that had been isolated previously by reverse phase high-performance liquid chromatography (HPLC). Peptidoglycan fragments that represent the attachment sites of lipoprotein to peptidoglycan were enzymatically released, separated by reverse phase HPLC, and finally characterized by time-of-flight mass spectrometric techniques (252Cf-PD TOF/MS, MALDI TOF/MS). The results obtained with both techniques differed only in the better sensitivity obtained with MALDI TOF/MS, which consumed a factor of 100 to 1000 less material than with PD TOF/MS