Women’s Perceptions and Experiences of Fetal Macrosomia

Objective
to explore women's perceptions and experiences of pregnancy and childbirth following birth of a macrosomic infant (birth weight ≥4000 g).

Methods
a qualitative design utilising interviews conducted 13–19 weeks post partum in women's homes. The study was conducted in one Health and Social Care Trust in Northern Ireland between January and September 2010. Participants were identified from a larger cohort of women recruited to a prospective study exploring the impact of physical activity and nutrition on macrosomia. Eleven women who delivered macrosomic infants participated in this phase of the study.

Findings
four overarching themes emerged: preparation for delivery; physical and emotional impact of macrosomia; professional relations and perceptions of macrosomia. Findings highlighted the importance of communication with health professionals in relation to both prediction of macrosomia and decision making about childbirth, and offers further understanding into the physical and emotional impact of having a macrosomic infant on women. Furthermore, there was evidence that beliefs and perceptions relating to macrosomia may influence birth experiences and uptake of health promotion messages.

Key conclusions and implications for practice
this study provides important insight into women's experiences of macrosomia throughout the perinatal period and how they were influenced by previous birth experiences, professional relations and personal perceptions and beliefs about macrosomia. Pregnant women at risk of having a macrosomic infant may require extra support throughout the antenatal period continuing into the postnatal period. Support needs to be tailored to the woman's information needs, with time allocated to explore previous birth experiences, beliefs about macrosomia and options for childbirth.

Detailed validation of an automotive catalysis model using spatially resolved measurements within the catalyst substrate

Many kinetic models have appeared in literature in past decades using two main approaches: the traditional global kinetics approach, or the more complex micro-kinetics approach. Whether global or micro-kinetics, kinetic models have been based on experimental data obtained at the end of the monolith. The experimental procedure using end pipe analysis may give an accurate overview of the reaction mechanisms that occur; however, the lack of information from within the catalyst can ultimately lead to inaccuracies in the kinetic model and parameters used.

Using SpaciMS, a spatially resolved experimental technique developed at the Queen's University Belfast, information from within the catalyst can be obtained. This minimally invasive technique provides detailed information of the gas concentration and temperature profile from inside the catalytic monolith. This paper presents a kinetic model and simulations validated against experimental data obtained from three positions inside the catalyst monolith at 2, 14, and 26 mm in, using data from the SpaciMS. Also, simulations of end pipe analysis, using a commercial reactor, for the CO oxidation are presented and analyzed. The simulations presented are for varying concentrations of both CO and O2 (0.5 % and 1 % CO, 0.5 % and 2 % O2) for both the global and micro-kinetic approach.