Detection of Aliphatically Bridged Multi-Core Polycyclic Aromatic Hydrocarbons in Sooting Flames with Atmospheric-Sampling High-Resolution Tandem Mass Spectrometry.

This paper provides experimental evidence for the chemical structures of aliphatically substituted and bridged polycyclic aromatic hydrocarbon (PAH) species in gas-physe combustion environments. The identification of these single- and multicore aromatic species, which have been hypothesized to be important in PAH growth and soot nucleation, was made possible through a combination of sampling gaseous constituents from an atmospheric pressure inverse coflow diffusion flame of ethylene and high-resolution tandem mass spectrometry (MS-MS). In these experiments, the flame-sampled components were ionized using a continuous VUV lamp at 10.0 eV and the ions were subsequently fragmented through collisions with Ar atoms in a collision-induced dissociation (CID) process. The resulting fragment ions, which were separated using a reflectron time-of-flight mass spectrometer, were used to extract structural information about the sampled aromatic compounds. The high-resolution mass spectra revealed the presence of alkylated single-core aromatic compounds and the fragment ions that were observed correspond to the loss of saturated and unsaturated units containing up to a total of 6 carbon atoms. Furthermore, the aromatic structures that form the foundational building blocks of the larger PAHs were identified to be smaller single-ring and pericondensed aromatic species with repetitive structural features. For demonstrative purposes, details are provided for the CID of molecular ions at masses 202 and 434. Insights into the role of the aliphatically substituted and bridged aromatics in the reaction network of PAH growth chemistry were obtained from spatially resolved measurements of the flame. The experimental results are consistent with a growth mechanism in which alkylated aromatics are oxidized to form pericondensed ring structures or react and recombine with other aromatics to form larger, potentially three-dimensional, aliphatically bridged multicore aromatic hydrocarbons

Functional performance according to gestational age and birth weight of preschool children born premature or with low weight

Premature labour is a major health problem.Besides medical factors, risk factors include lowersocial class, less education, single marital status,low income younger maternal age, low body weight,ethnicity, smoking, poor housing. The long termsequelae can be severe and the cost - financiallyand socially - of care is high. Preterm birth is indeeda major clinical public heath problem that accountsfor nearly 50% of all neonatal deaths

Neonatal Psychology: Theories and Practice

Não se aplicaNão se aplic

Development of food photographs for use with children aged 18 months to 16 years:comparison against weighed food diaries – The Young Person’s Food Atlas (UK)

Traditional dietary assessment methods, used in the UK, such as weighed food diaries impose a large participant burden, often resulting in difficulty recruiting representative samples and underreporting of energy intakes. One approach to reducing the burden placed on the participant is to use portion size assessment tools to obtain an estimate of the amount of food consumed, removing the need to weigh all foods. An age range specific food atlas was developed for use in assessing children’s dietary intakes. The foods selected and portion sizes depicted were derived from intakes recorded during the UK National Diet and Nutrition Surveys of children aged 1.5 to 16 years. Estimates of food portion sizes using the food atlas were compared against 4-day weighed intakes along with in-school / nursery observations, by the research team. Interviews were conducted with parents the day after completion of the diary, and for children aged 4 to 16 years, also with the child. Mean estimates of portion size consumed were within 7% of the weight of food recorded in the weighed food diary. The limits of agreement were wide indicating high variability of estimates at the individual level but the precision increased with increasing age. For children 11 years and over, agreement with weighed food diaries, was as good as that of their parents in terms of total weight of food consumed and of intake of energy and key nutrients. The age appropriate food photographs offer an alternative to weighed intakes for dietary assessment with children

Understanding the impact of newborn touch upon mothers of hospitalized preterm neonates.

Many interventions have been designed to support the development of the preterm baby and minimise the complications of prematurity. However, there is limited evidence of the possible psychological benefits of touch to the mother when she is the one performing the support programme during the hospitalisation of her newborn. This study explored whether the type of touch provided to preterm neonates had an impact on maternal self-efficacy, self-esteem and maternal-to-infant attachment, as-well-as newborn weight gain. Using a randomised cluster trial, forty babies and their mothers were allocated to one of two groups receiving either a touch-based intervention (TAC-TIC; Touching And Caressing; Tender In Caring) or spontaneous touch. Mothers who provided the touch-based intervention demonstrated greater increases in self-efficacy, self-esteem and attachment, and babies gained more weight than those using spontaneous touch. The results indicate that systematic touch interventions may be used to facilitate the mother-baby relationship as well as to promote newborn weight gain