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- Semidirect products and crossed modules in monoids with operationsPublication . Martins-Ferreira, Nelson; Montoli, Andrea; Sobral, ManuelaWe describe actions, semidirect products and crossed modules in categories of monoids with operations. Moreover we characterize, in this context, the internal categories corresponding to crossed modules. Concrete examples in the cases of monoids, semirings and distributive lattices are given.
- Are authentic leaders associated with more virtuous, committed and potent teams?Publication . Rego, Arménio; Vitória, Andreia; Magalhães, Ana; Ribeiro, Neuza; Pina e Cunha, MiguelThrough a team-level analysis, the study shows how authentic leadership (AL) predicts team potency both directly and through the mediating role of team virtuousness and team affective commitment. Data about AL and team virtuousness were collected two months before data collection on team affective commitment and team potency. Fifty-one teams were selected for testing the hypotheses. The main findings are the following: (a) AL predicts team affective commitment through the mediating role of team virtuousness; (b) team virtuousness predicts team potency through the mediating role of team affective commitment; (c) AL predicts team potency through the mediating role of team virtuousness and team affective commitment. By focusing on two positive constructs (AL and team virtuousness), for which interrelations have rarely been explored, the study contributes to the Positive Organizational Scholarship movement, and suggests that AL and virtuousness are good in themselves and also potential facilitators of team success.
- Influence of tool shoulder geometry on properties of friction stir welds in thin copper sheetsPublication . Galvão, I.; Leal, Rui M.; Rodrigues, D.M.; Loureiro, A.The aim of this work is to study the influence of the shoulder geometry on friction stir welding of 1mmthick copper-DHP plates. The welds were produced using three different shoulder geometries, flat, conical and scrolled, and varying the rotation and traverse speeds of the tool. The flat shoulder tool proved to be inadequate for performing welds, because many defects were produced for all welding conditions. In turn, the scrolled shoulder tool is more effective than the conical one in the production of defect free welds. However, both geometries required a minimum rotational speed to avoid internal defects. For the same welding parameters, greater grain refinement, higher hardness and improved strength are also achieved in the nugget of the welds, using the scrolled tool.
- Dissemination of Antimicrobial-Resistant Clones of Salmonella enterica Among Domestic Animals, Wild Animals, and HumansPublication . Palomo, Gonzalo; Campos, Maria Jorge; Ugarte, María; Porrero, María Concepción; Alonso, Juan Manuel; Borge, Carmen; Vadillo, Santiago; Domínguez, Lucas; Quesada, Alberto; Píriz, SegundoNon-typhoidal salmonellosis is an important zoonotic disease caused by Salmonella enterica. This work focuses on the identification of Salmonella enterica clonal strains which, presenting a wide distribution potential, express resistance determinants that compromise effectiveness of the antimicrobial therapy. The screening was performed on 506 Salmonella enterica isolates from animals and humans, which were characterized by serovar and phage typing, genome macrorestriction and pulsed-field gel electrophoresis, and detection of phenotypic and genotypic traits for antimicrobial resistance. A Salmonella Enteritidis strain with strong quinolone resistance is spread on three host environments carrying one of the four variants found for the GyrA protein: (1) Asp87Tyr, the major polymorphism found in 39 Salmonella isolates from human origin and six from poultry; (2) Ser83Phe, with four isolates from human origin and one from white stork (Ciconia ciconia); and (3) Asp87Asn or (4) Asp87Gly, with two isolates each from human origins. Several Salmonella Typhimurium strains that presented int1 elements and the classically associated pentaresistance (ACSSuT) phenotype were found distributed between two host environments: domestic animals and humans, domestics and wild animals, or wild fauna plus humans. This study points out the importance of monitoring gut microbiota and its antimicrobial resistance from wildlife, in parallel to livestock animals and humans, especially for animal species that are in close contact with people.
- Refletindo sobre a Prática Pedagógica – Ideias das crianças de 6/7 anos relativamente aos conceitos sólido e líquidoPublication . Ferreira, Vanessa Gaspar; Saraiva, Alzira Maria Rascão
- Estudo investigativo sobre a perceção das crianças de 1º ano do 1.º Ciclo do Ensino Básico acerca da sua escolaPublication . Ribeiro, Sara Cardoso; Milhano, Sandrina Diniz Fernandes