Maternal control of child-feeding during breast and formula feeding in the first 6 months post-partum.

BACKGROUND: Mothers who breastfeed use lower levels of control over later child diet. The baby-led nature of breastfeeding may encourage this low control to develop. Alternatively maternal desire for control may drive breastfeeding duration. The present study explored whether differences in maternal control are present during milk feeding and whether these stem from or drive breastfeeding duration. METHODS: Five hundred and two mothers with an infant aged 6-12 months completed a modified retrospective version of the child-feeding questionnaire adapted to reflect milk feeding during the first 6 months post-partum. Participants were recruited from mother and baby groups and online parenting forums. Mothers recalled their use of encouraging intake and scheduling feeds in relation to their infant's intake of milk. Attitudes towards breastfeeding were also measured, including views that breastfeeding is inconvenient, difficult and that formula-fed infants were more content. RESULTS: Compared to mothers who formula-fed or ceased breastfeeding within 1 week, mothers who breastfed for at least 6 months recalled a lower use of scheduling and encouraging milk feeds. Mothers who initiated breastfeeding but ceased within 1 week reported lower control compared to exclusive formula feeders. A high level of scheduling feeds was associated with considering that breastfeeding was inconvenient and a greater perceived infant size, whereas encouraging feeds was associated with considering that breastfeeding was difficult, low maternal confidence and a smaller perceived infant size. CONCLUSIONS: Maternal desire for control may drive breastfeeding duration. A controlling maternal feeding style may therefore be dispositional and present much earlier than current studies suggest.

Collection of biological and non-biological particles by new and used filters made from glass and electrostatically charged synthetic fibers.

UNLABELLED: Synthetic filters made from fibers carrying electrostatic charges and fiberglass filters that do not carry electrostatic charges are both utilized commonly in heating, ventilating, and air-conditioning (HVAC) systems. The pressure drop and efficiency of a bank of fiberglass filters and a bank of electrostatically charged synthetic filters were measured repeatedly for 13 weeks in operating HVAC systems at a hospital. Additionally, the efficiency with which new and used fiberglass and synthetic filters collected culturable biological particles was measured in a test apparatus. Pressure drop measurements adjusted to equivalent flows indicated that the synthetic filters operated with a pressure drop less than half that of the fiberglass filters throughout the test. When measured using total ambient particles, synthetic filter efficiency decreased during the test period for all particle diameters. For particles 0.7-1.0 mum in diameter, efficiency decreased from 92% to 44%. It is hypothesized that this reduction in collection efficiency may be due to charge shielding. Efficiency did not change significantly for the fiberglass filters during the test period. However, when measured using culturable biological particles in the ambient air, efficiency was essentially the same for new filters and filters used for 13 weeks in the hospital for both the synthetic and fiberglass filters. It is hypothesized that the lack of efficiency reduction for culturable particles may be due to their having higher charge than non-biological particles, allowing them to overcome the effects of charge shielding. The type of particles requiring capture may be an important consideration when comparing the relative performance of electrostatically charged synthetic and fiberglass filters. PRACTICAL IMPLICATIONS: Electrostatically charged synthetic filters with high initial efficiency can frequently replace traditional fiberglass filters with lower efficiency in HVAC systems because properly designed synthetic filters offer less resistance to air flow. Although the efficiency of charged synthetic filters at collecting non-biological particles declined substantially with use, the efficiency of these filters at collecting biological particles remained steady. These findings suggest that the merits of electrostatically charged synthetic HVAC filters relative to fiberglass filters may be more pronounced if collection of biological particles is of primary concern.

Employers' expectations of knowledge and skills of master's-trained industrial hygienists.

Certified industrial hygienists with recent hiring experience were surveyed about their expectations of competencies when hiring entry-level master's-trained industrial hygienists. Results were used to affirm educational objectives and program outcomes required by new program accreditation criteria. We received 129 completed surveys from 179 eligible participants agreeing to participate. Most of the respondents were employed in very large companies (>500 employees) and were evenly distributed in manufacturing, services, and public administration. More than 70% of respondents identified essential knowledge and skills in 11 topic areas that fall entirely within the categories of recognition, evaluation, and control. Environmental and management topics were identified as essential by less than 25% of the respondents. Nineteen competencies identified as essential by 60% of the respondents were entirely in the categories of recognition, evaluation, control, and communication. Less than 50% of the respondents thought competencies in the management area were useful but not essential. Air sampling pumps, sound level meters, noise dosimeters, and direct-reading instruments were the mostfrequently listed equipment with which industrial hygienists should be familiar. These survey results represent the first systematic input from employers on their expectations for competencies of master's-trained industrial hygienists.

Anthropometric indices of failure to thrive.

AIMS: To compare five anthropometric methods of classifying failure to thrive in order to ascertain their relative merits in predicting developmental, dietary, and eating problems. METHODS: The five anthropometric methods were compared in 83 children with failure to thrive. RESULTS: The methods were inconsistent in classification of severity, and no one method was superior in predicting problems. CONCLUSIONS: Weight alone, being the simplest, is still the most reasonable marker for failure to thrive and associated problems.

Modeling evaporative loss of oil mist collected by sampling filters.

Oil mists can cause respiratory distress and have been linked to skin and gastrointestinal cancers in workers. Standard concentration assessment methods call for sampling these mists with fibrous or membrane filters. Previous experimental studies using glass fiber (GF) filters and polyvinyl chloride and polytetrafluoroethylene membrane filters indicate that mist sampled onto filters may volatilize. A model has been developed to predict the evaporation of mist collected on a fibrous sampling filter. Evaporation of retained fluid from membrane filters can be modeled by treating the filter as though it is a fibrous filter. Predictions from the model exhibit good agreement with experimental results. At low mist concentrations, the model indicates that evaporation of retained mineral oil occurs readily. At high mist concentrations, significant evaporation from the filters is not expected because the vapor accompanying the airborne mist is already saturated with the compounds in the oil. The findings from this study indicate that sampling mineral oil mist with filters in accordance with standard methods can lead to estimates of worker exposure to oil mist that are too low.

A randomised controlled trial of specialist health visitor intervention for failure to thrive.

AIMS: To determine whether home intervention by a specialist health visitor affects the outcome of children with failure to thrive. METHODS: Children referred for failure to thrive were randomised to receive conventional care, or conventional care and additional specialist home visiting for 12 months. Outcomes measured were growth, diet, use of health care resources, and Bayley, HAD (hospital anxiety and depression), and behavioural scales. RESULTS: Eighty three children, aged 4-30 months, were enrolled, 42 received specialist health visitor intervention. Children in both groups showed good weight gain (mean (SD) increase in weight SD score for the specialist health visitor intervention group 0.59 (0.63) v 0.42 (0.62) for the control group). Children < 12 months in the intervention group showed a higher mean (SD) increase in weight SD score than the control group (0.82 (0.86) v 0.42 (0.79)). Both groups improved in developmental score and energy intake. No significant differences were found for the primary outcome measures, but controls had significantly more dietary referrals, social service involvement, and hospital admissions, and were less compliant with appointments. CONCLUSIONS: The study failed to show that specialist health visitor intervention conferred additional benefits for the child. However, the specialist health visitor did provide a more coordinated approach, with significant savings in terms of health service use. Problems inherent to health service research are discussed.

What do we know about children who fail to thrive?

It is the aim of this article to provide an overview of difficulties in children with poor growth enrolled in an intensive community intervention trial for failure to thrive (FTT). Children were assessed for developmental delay (Bayley test), inadequate diet, iron deficiency, eating and other behavioural problems, and maternal anxiety and depression (HAD Scales). Sixty-three children aged 6 months to 2 1/2 years were studied. The majority of children were from families living in poverty with many from divorced, separated or single families. On developmental testing (Bayley Developmental Scales) 55% were delayed, 27% severely. Seventy-seven per cent had caloric intakes below the expected average requirement (EAR) with 19% reported at less than 50% of requirements. Iron intakes were similarly low and one-third had iron deficiency anaemia on testing. Sixty per cent of children were reported to have eating difficulties, principally in terms of responding negatively to food. Eating difficulties had commonly presented within the first weeks of life. Other behavioural and sleeping difficulties were also common. Children identified as failing to thrive in the community are likely to have associated developmental, dietary and behavioural problems which may not be immediately evident and to an extent which may require intensive multidisciplinary involvement.

Attachment of boar sperm to mucosal explants of oviduct in vitro: possible role in formation of a sperm reservoir.

Ejaculated boar sperm were incubated with explants of porcine oviductal mucosa that had been dissected from the isthmic and ampullar regions of gilts. Sperm bound within minutes to the epithelial surfaces of the explants. Binding was not affected by region (isthmus or ampulla) nor day of estrous cycle (Day 0 or Day 10), but was increased by addition of 70 pg/ml 17 beta-estradiol to the medium. Scanning electron micrographs indicated that sperm bound, via the acrosomal region, to ciliated cells. After 24 h, the numbers of bound sperm dropped significantly, but the motility of the bound sperm did not. A mucous material that entrapped sperm was observed on the epithelial surfaces of 23/32 isthmic and only 4/32 ampullar explants. These results indicate that sperm sticking to ciliated cells and mucus can create a sperm reservoir in the isthmus, but the means by which sperm are released remain unknown.