Measurement of energy expenditure of daily tasks among mothers of young children

There is currently some debate about whether the energy expenditure of domestic tasks is sufficient to confer health benefits. The aim of this study was therefore to measure the energy cost of five activities commonly undertaken by mothers of young children. Seven women with at least one child younger than five years of age spent 15 minutes in each of the following activities: sitting quietly, vacuum cleaning, washing windows, walking at moderate pace (approx 5km/hour), walking with a stroller and grocery shopping in a super-market. Each of the six 'trials' was completed on the same day, in random order. A carefully calibrated portable gas analyser was used to measure oxygen uptake during each activity, and data were converted to units of energy expenditure (METS). Vacuum cleaning, washing windows and walking with and without a stroller were found to be 'moderate intensity activities' (3 to 6 METs), but supermarket shopping did not reach this criterion. The MET values for these activities were similar to those reported in the Compendium of Physical Activities (Ainsworth et al., 2000). However, the energy expenditures of walking, both with and without a stroller, were higher than those reported in the Compendium. The findings suggest that some of the tasks associated with domestic caring duties are conducted at an intensity which is sufficient to confer some health benefit. Such benefits will only accrue however if the daily duration of these activities is sufficient to meet current guidelines.

Analysis of the gate capacitance measurement technique and its application for the evaluation of hot-carrier degradation in submicrometer MOSFETs

The use of gate-to-drain capacitance (C-gd) measurement as a tool to characterize hot-carrier-induced charge centers in submicron n- and p-MOSFET's has been reviewed and demonstrated. By analyzing the change in C-gd measured at room and cryogenic temperature before and after high gate-to-drain transverse field (high field) and maximum substrate current (I-bmax) stress, it is concluded that the degradation was found to be mostly due to trapping of majority carriers and generation of interface states. These interface states were found to be acceptor states at top half of band gap for n-MOSFETs and donor states at bottom half of band gap for p-MOSFETs. In general, hot electrons are more likely to be trapped in gate oxide as compared to hot holes while the presence of hot holes generates more interface states. Also, we have demonstrated a new method for extracting the spatial distribution of oxide trapped charge, Q(ot), through gate-to-substrate capacitance (C-gb) measurement. This method is simple to implement and does not require additional information from simulation or detailed knowledge of the device's structure. (C) 2001 Elsevier Science Ltd. All rights reserved.

Benchmarking nitrogen removal suspended-carrier biofilm systems using dynamic simulation

We are witnessing an enormous growth in biological nitrogen removal from wastewater. It presents specific challenges beyond traditional COD (carbon) removal. A possibility for optimised process design is the use of biomass-supporting media. In this paper, attached growth processes (AGP) are evaluated using dynamic simulations. The advantages of these systems that were qualitatively described elsewhere, are validated quantitatively based on a simulation benchmark for activated sludge treatment systems. This simulation benchmark is extended with a biofilm model that allows for fast and accurate simulation of the conversion of different substrates in a biofilm. The economic feasibility of this system is evaluated using the data generated with the benchmark simulations. Capital savings due to volume reduction and reduced sludge production are weighed out against increased aeration costs. In this evaluation, effluent quality is integrated as well.

Characterization of a chemsensory protein (ASP3c) from honeybee (Apis mellifera L.) as a brood pheromone carrier

Chemosensory proteins (CSPs) are ubiquitous soluble small proteins isolated from sensory organs of a wide range of insect species, which are believed to be involved in chemical communication. We report the cloning of a honeybee CSP gene called ASP3c, as well as the structural and functional characterization of the encoded protein. The protein was heterologously secreted by the yeast Pichia pastoris using the native signal peptide. ASP3c disulfide bonds were assigned after trypsinolysis followed by chromatography and mass spectrometry combined with microsequencing. The pairing (Cys(I)-Cys(II), Cys(III)-Cys(IV)) was found to be identical to that of Schistocerca gregaria CSPs, suggesting that this pattern occurs commonly throughout the insect CSPs. CD measurements revealed that ASP3c mainly consists of alpha-helices, like other insect CSPs. Gel filtration analysis showed that ASP3c is monomeric at neutral pH. Using ASA, a fluorescent fatty acid anthroyloxy analogue as a probe, ASP3c was shown to bind specifically to large fatty acids and ester derivatives, which are brood pheromone components, in the micromolar range. It was unable to bind tested general odorants and other tested pheromones (sexual and nonsexual). This is the first report on a natural pheromonal ligand bound by a recombinant CSP with a measured affinity constant.

Paid employment of mothers and fathers of an adult child with multiple disabilities

Background Paid employment is increasingly undertaken by mothers as their children age, with the majority of women being in employment by the time their offspring are adult. Opportunities to engage in employment appear to be reduced for mothers of children with disabilities; however, little is known about the employment of mothers or fathers of adults with disabilities. Method Data were collected regarding the employment decisions of parents of a young adult with multiple disabilities and contrasted with those of parents whose children were all developing normally. Twenty-five mothers and 12 fathers of a young adult with multiple disabilities were interviewed, as were 25 comparison mothers and 19 comparison fathers. Data collected included hours of work, reasons for employment status, attitudes towards work and child care, and psychological well-being. Results Clear differences were found between the two groups. Mothers and fathers of a child with multiple disabilities showed different engagement patterns with the paid workforce from comparison parents. Hours of work for fathers of a young adult with multiple disabilities showed a bi-modal distribution, with some fathers working fewer hours than usual and others working very long hours. For mothers in both groups, the number of hours in paid employment was negatively associated with reports of psychological problems. Conclusions Increased attention needs to be given to the employment opportunities of parents of children with disabilities since employment appears to play a protective role for mothers, in particular. Services provided to adults with disabilities will need to change if parents are to have the same life chances as parents without adult offspring with a disability.

A lipophilic adjuvant carrier system for antigenic peptides

A lipoamino acid based synthetic peptide, (Lipid Core Peptide, LCP) derived from the conserved region of group A streptococci (GAS) was evaluated as potential candidate in a vaccine to prevent GAS-associated diseases, including rheumatic heart disease and post-streptococcal acute glomerulonephritis. Multiple copies of a peptide sequence from the bacterial surface M protein were incorporated into a lipid core and it was used to immunize mice with and without the application of adjuvant. The LCP construct had significantly enhanced immunogenicity compared with the monomeric peptide epitope. Furthermore, the peptides incorporated into the LCP system generated antibodies without the use of any conventional adjuvant.

Lipoamino acid-based adjuvant carrier system: Enhanced immunogenicity of group a streptococcal peptide epitopes

Lipoamino acid-based synthetic peptides (lipid core peptides, LCP) derived from the type-specific and conserved region determinants of group A streptococci (GAS) were evaluated as potential candidate sequences in a vaccine to prevent GAS-associated diseases, including rheumatic heart, disease and poststreptococcal acute glomerulonephritis. The LCP peptides had significantly enhanced immunogenicity as compared with the monomeric peptide epitopes. Furthermore, the peptides incorporated into the LCP system generated epitope-specific antibodies without the use of any conventional adjuvant.

Postpartum issues' for expectant mothers and fathers

Objective: To investigate the postpartum psychosocial and infant care topics that women and men who attend preparation for parenthood classes have been thinking or worrying about during the pregnancy. Furthermore, to compare the rates of endorsement of such issues for women and men so that clinicians can use this information to help plan which topics to include in preparation for parenthood classes. Design: A survey of expectant parents attending preparation for parenthood classes at a local public hospital. Participants completed a 17- to 19-item postpartum issues checklist devised for the study. Setting: Preparation for parenthood classes conducted in a public hospital in South Western Sydney, Australia. Participants: People attending the session were in their 2nd to 3rd trimester, of low to middle socioeconomic status, and 95% were expecting their first child. Eighty-five percent of women were accompanied by their male partner at the session. Data are reported from 201 women and 182 men. Measure: A 17-item issues checklist was devised initially and later expanded to 19 items. The initial checklist covered three psychosocial issues: interpersonal, intrapersonal, and parental competency. The expanded checklist also included items on infant care issues. Participants rated each item as to the extent to which they had been thinking or worrying about it over the past few weeks. Results: More than half of the men and women had been thinking or worrying about their ability to cope as new parents; just less than half of both men and women endorsed the item regarding the effect having a baby would have on their relationship with their partner; approximately 40% of women had thought that they might get bored or lonely when at home with the baby, and an equal rate of men reported that their partner experiencing this sense of boredom or loneliness was an issue for them. There were few differences between the genders in the rate of endorsement on the issues checklist. Conclusion: That many of the issues on the checklist are prevalent in both women and men at this time in the pregnancy would suggest that these are topics that would be pertinent for inclusion at preparation for parenthood classes. Although the checklist is not exhaustive, the data reported give empirical justification for inclusion of these topics in such classes.

Food Cent$: Educating mothers with a mental illness about nutrition

People with a mental illness can have deficits in a range of areas, including food skills. Mothers who have a mental illness and have residential care of their children are particularly vulnerable to experiencing food insecurity. The food skills programme known as Food Cent$ is a new way of spending money on food using the 10-plan, so that people can learn to balance their diet and their food budget. Occupational therapists in a mental health rehabilitation service incorporated the use of Food Cent$ into a parenting programme for mothers with a mental illness. A pilot study was conducted to identify whether the Food Cent$ programme influenced behaviours and attitudes towards food and food selection and preparation and reduced grocery expenditure. The participants were six mothers with a mental illness who had children under 5 years of age in their care. A focus group was conducted to gain insight into the experiences of mothers who had attended the programme. Supermarket receipts were collected before and after the project to determine changes in dietary practices. The results indicated that attending Food Cent$ contributed to an improvement in dietary intake, food selection and preparation, and grocery expenditure. Further research is required into the effectiveness of this programme with other target groups likely to experience food insecurity.

Accuracy of Mothers' Retrospective Reports of Smoking During Pregnancy: Comparison with Twin Sister Informant Ratings

Retrospective assessment of maternal smoking or substance use during pregnancy is sometimes unavoidable. The unusually close relationship of twin sister pairs permits comparison of self-report data versus co-twin informant data on substance use during pregnancy. Information about smoking during pregnancy has been gathered from a series of mothers from an Australian volunteer twin panel (576 women reporting on 995 pregnancies), supplemented in many cases by independent ratings of their smoking by twin sister informants (821 pregnancies). Estimates of the proportion of women who had never smoked regularly (56-58%), who had smoked but did not smoke during a particular pregnancy (16-21%), or who smoked throughout the pregnancy (16-18%), were in good agreement whether based on self-report or twin sister informant data. However, informants underreported cases who smoked during the first trimester but then quit (1-3% versus 7-9% by self-report). Women who smoked throughout pregnancy (by informant report) rarely denied a history of regular smoking (

Serum inhibin A and B concentrations during the menstrual cycle in mothers of spontaneous dizygotic twins

Dizygotic twinning in humans is influenced by genetic factors suggesting inherited variation affects follicle development and predisposes to double ovulations. In a previous study, we conducted a detailed examination of follicle development and variation in hormone concentrations during the menstrual cycle in mothers of DZ twins (MODZT) compared with an age-matched control group of mothers of singletons. We did not detect differences in FSH concentrations between mothers of twins and mothers of singletons. Serum inhibin concentrations were measured by a radioimmunoassay that did not distinguish between dimeric inhibin A and B forms and free inhibin alpha subunit. We therefore analyzed the samples from this study with specific assays to determine whether concentrations of inhibin A and B were different between MODZT and controls and therefore contribute to the twinning phenotype. There were no significant differences between MONT with single ovulations and control women in inhibin A and B concentrations during the cycle, including the critical period for the selection of the dominant follicle. These data suggest that the genetic cause of twinning is not associated with changes in FSH concentrations or recognised feedback mechanisms regulating FSH release.

Opening windows into the mind: mothers' preferences for mental state explanations and children's theory of mind

A new questionnaire, the Maternal Mental State Input Inventory (MMSII) was created to measure mothers' preferences for introducing and elaborating on mental states in conversation with their young children. In two studies, the questionnaire was given to mothers of young children, and the children's theory of mind (ToM) development was assessed with standard tasks. In both studies, the questionnaire exhibited good internal reliability, and significant correlations emerged between mothers' self-reported preferences for elaborated, explanatory talk about the mental states and children's theory of mind performance. Further, mothers' conversational preferences, as measured by the MMSII, were the best predictors of children's theory of mind development when relevant control variables were included in the analyses. These results converge with naturalistic observational research that has demonstrated links between mothers' conversational styles and their children's theory of mind. They go further in suggesting that mothers' tendencies toward elaborated, explanatory talk about a range of mental states is particularly beneficial to children's theory of mind development. (C) 2003 Elsevier Inc. All rights reserved.