Production of whey protein-based aggregates under ohmic heating

Formation of whey protein isolate protein aggregates under the influence of moderate electric fields upon ohmic heating (OH) has been monitored through evaluation of molecular protein unfolding, loss of its solubility, and aggregation. To shed more light on the microstructure of the protein aggregates produced by OH, samples were assayed by transmission electron microscopy (TEM). Results show that during early steps of an OH thermal treatment, aggregation of whey proteins can be reduced with a concomitant reduction of the heating chargeby reducing the come-up time (CUT) needed to reach a target temperatureand increase of the electric field applied (from 6 to 12 V cm1). Exposure of reactive free thiol groups involved in molecular unfolding of -lactoglobulin (-lg) can be reduced from 10 to 20 %, when a CUT of 10 s is combined with an electric field of 12 V cm1. Kinetic and multivariate analysis evidenced that the presence of an electric field during heating contributes to a change in the amplitude of aggregation, as well as in the shape of the produced aggregates. TEM discloses the appearance of small fibrillar aggregates upon the influence of OH, which have recognized potential in the functionalization of food protein networks. This study demonstrated that OH technology can be used to tailor denaturation and aggregation behavior of whey proteins due to the presence of a constant electric field together with the ability to provide a very fast heating, thus overcoming heat transfer limitations that naturally occur during conventional thermal treatments.

A cumulative risk model of child physical maltreatment potential: findings from a community-based study

"Published online before print November 20, 2015"

Childhood history of abuse and child abuse potential: the role of parent’s gender and timing of childhood abuse

It has been suggested that being physically abused leads to someone becoming a perpetrator of abuse which could be associated to parents' gender, timing of the physical abuse and specific socio-demographic variables. This study aims to investigate the role the parents' gender, timing of childhood abuse and socio-demographic variables on the relationship between parents' history of childhood physical abuse and current risk for children. The sample consisted of 920 parents (414 fathers, 506 mothers) from the Portuguese National Representative Study of Psychosocial Context of Child Abuse and Neglect who completed the Childhood History Questionnaire and the Child Abuse Potential Inventory. The results showed that fathers had lower current potential risk of becoming physical abuse perpetrators with their children than mothers although they did not differed in their physical victimization history. Moreover, the risk was higher in parents (both genders) with continuous history of victimization than in parents without victimization. Prediction models showed that for fathers and mothers separately similar socio-demographic variables (family income, number of children at home, employment status and marital status) predicted the potential risk of becoming physical abuses perpetrators. Nevertheless, the timing of victimization was different for fathers (before 13 years old) and mothers (after 13 years old). Then our study targets specific variables (timing of physical abuse, parents' gender and specific socio-demographic variables), which may enable professionals to select groups of parents at greater need of participating in abuse prevention programs.

Insights into bacterial colony morphology evolution and diversification during infection development in cystic fibrosis

Tese de Doutoramento em Engenharia Biomédica.

Optimização do processo de recolha de resíduos: desenvolvimento de ferramentas de investigação operacional para o problema de orientação de equipas com multi-restrições

Tese de Doutoramento em Engenharia Industrial e de Sistemas.

Catheter ablation of atriofascicular Mahaim fibers guided by the activation potential

OBJECTIVE: To determine whether recording of the activation potential may be used as an isolated criterion to guide catheter ablation of atriofascicular Mahaim fibers. METHODS: We studied 6 patients (5 females, mean age of 26±7.3 years) with paroxysmal tachycardias with a wide QRS complex, whose electrophysiological study diagnosed atriofascicular Mahaim fibers. Mapping and catheter ablation were performed in sinus rhythm, guided only by the recording of the activation potential of the fiber. RESULTS: Efficacy in ablation was achieved in all patients. The fibers were located in the right lateral region of the tricuspid ring in 3 patients, right posterolateral region in 2, and right anterolateral region in 1. A mean of 5.3±3 radiofrequency applications was performed. The mean fluoroscopy time was 46.6±25 minutes, and the mean duration of the procedure was 178.6±108 minutes. No complication occurred. In a mean 20-month follow-up, all patients were asymptomatic and receiving no antiarrhythmic drugs. CONCLUSION: Catheter ablation of Mahaim fibers may be performed with good safety and efficacy by mapping the activation potential of the tricuspid ring in sinus rhythm.