Quantitative image analysis as a tool for Yarrowia lipolytica dimorphic growth evaluation in different culture media

Yarrowia lipolytica, a yeast strain with a huge biotechnological potential, capable to produce metabolites such as γ-decalactone, citric acid, intracellular lipids and enzymes, possesses the ability to change its morphology in response to environmental conditions. In the present study, a quantitative image analysis (QIA) procedure was developed for the identification and quantification of Y. lipolytica W29 and MTLY40-2P strains dimorphic growth, cultivated in batch cultures on hydrophilic (glucose and N-acetylglucosamine (GlcNAc) and hydrophobic (olive oil and castor oil) media. The morphological characterization of yeast cells by QIA techniques revealed that hydrophobic carbon sources, namely castor oil, should be preferred for both strains growth in the yeast single cell morphotype. On the other hand, hydrophilic sugars, namely glucose and GlcNAc caused a dimorphic transition growth towards the hyphae morphotype. Experiments for γ-decalactone production with MTLY40-2P strain in two distinct morphotypes (yeast single cells and hyphae cells) were also performed. The obtained results showed the adequacy of the proposed morphology monitoring tool in relation to each morphotype on the aroma production ability. The present work allowed establishing that QIA techniques can be a valuable tool for the identification of the best culture conditions for industrial processes implementation.

An object-oriented model for rapid prototyping of data path/control systems - a case study

Publicado em "Information control in manufacturing 1998 : (INCOM'98) : advances in industrial engineering : a proceedings volume from the 9th IFAC Symposium, Nancy-Metz, France, 24-26 June 1998. Vol. 2"

Object-oriented inheritance of statecharts for control applications

This paper discusses how object-oriented iuheritance can be re-interpreted if statecharts are used for modelling the dynamic behaviour of an object. The support of inheritance of statecharts allows the improvement of systems' development by easing the reutilization of parts of already developed euccessful systems, aad by promoting the iterative and continuous models' refinement advocated by the operatioaal approach. Statechart is the formalism used within UML to specify reactive state.based behaviours. This paper covers the use of statecharts within the modelling of embedded systems for industrial control applxications, where performance and memory usage are main concerns.

The influence of fibre orientation on the post-cracking tensile behaviour of steel fibre reinforced self-compacting concrete

Adding fibres to concrete provides several advantages, especially in terms of controlling the crack opening width and propagation after the cracking onset. However, distribution and orientation of the fibres toward the active crack plane are significantly important in order to maximize its benefits. Therefore, in this study, the effect of the fibre distribution and orientation on the post-cracking tensile behaviour of the steel fibre reinforced self-compacting concrete (SFRSCC) specimens is investigated. For this purpose, several cores were extracted from distinct locations of a panel and were subjected to indirect (splitting) and direct tensile tests. The local stress-crack opening relationship (σ-w) was obtained by modelling the splitting tensile test under the finite element framework and by performing an Inverse Analysis (IA) procedure. Afterwards the σ-w law obtained from IA is then compared with the one ascertained directly from the uniaxial tensile tests. Finally, the fibre distribution/orientation parameters were determined adopting an image analysis technique.

High performance fiber reinforced concrete for the shear reinforcement: experimental and numerical research

High performance fiber reinforced concrete (HPFRC) is developing rapidly to a modern structural material with unique rheological and mechanical characteristics. Despite applying several methodologies to achieve self15 compacting requirements, some doubts still remain regarding the most convenient strategy for developing a HPFRC. In the present study, an innovative mix design method is proposed for the development of high17 performance concrete reinforced with a relatively high dosage of steel fibers. The material properties of the developed concrete are assessed, and the concrete structural behavior is characterized under compressive, flexural and shear loading. This study better clarifies the significant contribution of fibers for shear resistance of concrete elements. This paper further discusses a FEM-based simulation, aiming to address the possibility of calibrating the constitutive model parameters related to fracture modes I and II.

Avaliação do processo de implementação de PBL num curso de engenharia informática em Moçambique: as percepções dos estudantes

O presente artigo traz uma avaliação sobre um processo de implementação do PBL que ocorreu no curso de Engenharia Informática na Faculdade de Engenharia da Universidade Eduardo Mondlane em Moçambique. Por este processo ser novo no contexto de ensino de Engenharia em Moçambique foram os desafios encontrados por parte dos docentes e estudantes relativos a implementação, coordenação e adequação do currículo a metodologia do PBL, fazendo com que o processo de implementação fosse gradual. Assim no primeiro semestre de 2014 foi implementado um processo PBL piloto envolvendo as disciplinas de Programação Orientada à Objetos 1 e Base de Dados 1, que foram disciplinas escolhidas pelo facto de seus currículos terem matérias comuns, todos desafios e comentários dados pelos estudantes foram levados em conta no desenho do segundo processo PBL para o segundo semestre de 2014 que envolveu as disciplinas de Programação Orientada à Objetos 2, Base de Dados 2 e Sistemas de Multimídia fazendo com que houvesse mais informação para o terceiro processo envolvendo as disciplinas de Engenharia de Software 1 e Programação em Web. A avaliação do processo por parte dos estudantes, veio através de inquiridos onde os estudantes fizeram chegar as suas preocupações e ideias a respeito do PBL e dos moldes em que este estava a ser implementado no currículo. O processo de implementação do PBL pode ser considerado uma experiência bem sucedida e com futuro promissor e que de certeza vai ajudar a inovar os processos de ensino de engenharia em Moçambique.

Redes de Petri e VHDL na prototipagem rápida de sistemas digitais

O objectivo principal deste artigo é exemplificar a utilização de uma metodologia de especificação de sistemas digitais, baseada em Redes de Petri orientadas por objectos, para obter de uma forma rápida e simplificada um protótipo em VHDL do sistema pretendido. É considerado como exemplo um sistema digital, para o qual se efectua a especificação no modelo RdP-shobi e a partir da qual se pode gerar automaticamente código VHDL. Este exemplo permite demonstrar acerca da capacidade desta metodologia no projecto de sistemas digitais, suportado por princípios de orientação por objectos e por uma ferramenta de EDA concebida para o efeito.

Projecto de hardware digital orientado por objectos

Os limites entre os domínios do software e do hardware são cada vez mais ténues, pelo que técnicas inicialmente experimentadas no software têm vindo a ser gradualmente aplicadas no hardware. Este artigo pretende descrever o estado actual da utilização da tecnologia de programação orientada por objectos no projecto de hardware digital. São analisadas as vantagens e implicações quando se introduzem conceitos ligados à tecnologia orientada por objectos em projectos de hardware e é apresentado um exemplo utilizando uma das extensões orientadas por objectos da linguagem VHDL.

An evolutionary approach to the use of Petri net based models: from parallel controllers to HW/SW co-design

"A workshop within the 19th International Conference on Applications and Theory of Petri Nets - ICATPN’1998"

FISHji: new ImageJ macros for the quantification of fluorescence in epifluorescence images

Fluorescence in situ hybridization (FISH) is based on the use of fluorescent staining dyes, however, the signal intensity of the images obtained by microscopy is seldom quantified with accuracy by the researcher. The development of innovative digital image processing programs and tools has been trying to overcome this problem, however, the determination of fluorescent intensity in microscopy images still has issues due to the lack of precision in the results and the complexity of existing software. This work presents FISHji, a set of new ImageJ methods for automated quantification of fluorescence in images obtained by epifluorescence microscopy. To validate the methods, results obtained by FISHji were compared with results obtained by flow cytometry. The mean correlation between FISHji and flow cytometry was high and significant, showing that the imaging methods are able to accurately assess the signal intensity of fluorescence images. FISHji are available for non-commercial use at http://paginas.fe.up.pt/nazevedo/.