Development of a new U 200 pultrusion die to produce GRP composite profiles using different thermosetting resins

In this work, a steel heated pultrusion die was designed, developed and manufactured to produce U200 glass fibre reinforced thermosetting matrix (GRP) profiles. The finite element analysis (FEA) was used to predict and optimise the developed die heating by using cylindrical electrical powered cartridges. To assess the new die performance it was mounted in the 120 kN pultrusion line of the Portuguese company Vidropol SA and used to produce continuously U200 profiles able to meet all requirements specified for the E23 grade accordingly to the European Standard EN 13706: 2002. After setting up the type, orientation and sequence of layers in laminate, orthophthalic, isophthalic and bisphenolic unsaturated polyester as well as vinylester resins were used to produce glass fibre reinforced U 200 composite profiles. An appropriated catalyst system was selected and the processing variables optimised for each case, namely, pultrusion pull-speed and die temperature. Finally, the produced U200 profiles were submitted to visual inspection, calcination and mechanical tests, namely, flexural, tensional and interlaminar shear strength (ILSS) tests, to assess their accomplishment with the EN 13706 requirements.

Development of procedures for the design, optimization and manufacturing of customized orthopaedic and trauma implants: Geometrical/anatomical modelling from 3D medical imaging

Tese de Doutoramento (Programa Doutoral em Engenharia Biomédica)

Development and characterization of lipid-based nanosystems for controlled release of bioactive compounds

Tese de Doutoramento em Engenharia Química e Biológica.

Mother’s depression at childbirth does not contribute to the effects of antenatal depression on neonate’s behavioral development

Background: Maternal depression is a worldwide phenomenon that has been linked to adverse developmental outcomes in neonates. Aims: To study the effect of antenatal depression (during the third trimester of pregnancy) on neonate behavior, preference, and habituation to both the mother and a stranger’s face/voice. To analyze mother’s depression at childbirth as a potential mediator or moderator of the relationship between antenatal depression and neonate behavioral development. Method: A sample of 110 pregnant women was divided in 2 groups according to their scores on the Edinburgh Postnatal Depression Scale during pregnancy (EPDS; ≥10, depressed; <10, non-depressed). In the first 5 days after birth, neonatal performance on the Neonatal Behavioral Assessment Scale (NBAS) and in the ‘Preference and habituation to the mother’s face/voice versus stranger’ paradigm was assessed; each mother filled out an EPDS. Results: Neonates of depressed pregnant women, achieved lower scores on the NBASs (regulation of state, range of state, and habituation); did not show a visual/auditory preference for the mother’s face/voice; required more trials to become habituated to the mother’s face/voice; and showed a higher visual/auditory preference for the stranger’s face/voice after habituation compared to neonates of non-depressed pregnant women. Depression at childbirth does not contribute to the effect of antenatal depression on neonatal behavioral development. Conclusion: Depression even before childbirth compromises the neonatal behavioral development. Depression is a relevant issue and should be addressed as a routine part of prenatal health care.

Mother's anxiety and depression during the third pregnancy trimester and neonate's mother versus stranger's face/voice visual preference

Background: Neonates show visual preference for their mother's face/voice and shift their attention from their mother to a stranger's face/voice after habituation. Aim: To assess neonate's mother versus stranger's face/voice visual preference, namely mother's anxiety and depression during the third pregnancy trimester and neonate's: 1) visual preference for the mother versus the stranger's face/voice (pretest visual preference), 2) habituation to the mother's face/voice and 3) visual preference for the stranger versus the mother's face/voice (posttest visual preference). Method: Mothers (N=100) filled out the Edinburgh Postnatal Depression Scale (EPDS) and the State Anxiety Inventory (STAI) both at the third pregnancy trimester and childbirth, and the “preference and habituation to the mother's face/voice versus stranger” paradigm was administered to their newborn 1 to 5 days after childbirth. Results: Neonates of anxious/depressed mothers during the third pregnancy trimester contrarily to neonates of non-anxious/non-depressed mothers did not look 1) longer at their mother's than at the stranger's face/voice at the pretest visual preference (showing no visual preference for the mother), nor 2) longer at the stranger's face/voice in the posttest than in the pretest visual preference (not improving their attention to the stranger's after habituation). Conclusion: Infants exposed to mother's anxiety/depression at the third gestational trimester exhibit less perceptual/social competencies at birth.