The validity of self-reported energy intake as determined using the doubly labelled water technique

In the 1980s the development of the doubly labelled water (DLW) technique made it possible to determine the validity of dietary assessment methods using external, independent markers of intake in free-living populations. Since then, the accuracy of self-reported energy intake (EI) has been questioned on a number of occasions as under-reporting has been found to be prevalent in many different populations. This paper is a review of investigations using the DLW technique in conjunction with self-reported EI measures in groups including adults, children and adolescents, obese persons, athletes, military personnel and trekking explorers. In studies where a person other than the subject is responsible for recording dietary intake, such as parents of young children, EI generally corresponds to DLW determined energy expenditure. However, in instances where the subjects themselves report their intake, EI is generally under-reported when compared with energy expenditure. It was originally believed that this phenomenon of under-reporting was linked to increased adiposity and body size, however, it is now apparent that other factors, such as dietary restraint and socio-economic status, are also involved. This paper therefore aims to present a more comprehensive picture of under-reporting by tying in the findings of many DLW studies with other studies focusing particularly on the characteristics and mechanisms for under-reporting. Awareness of these characteristics and mechanisms will enable researchers to obtain more accurate self-reports of EI using all dietary recording techniques.

Cancer culture: Epidemics, human behaviour and the dubious search for new risk factors

The rise of melanoma and the almost complete decline of stomach cancer clearly reflect disturbances of human culture during the 20th century. Environmental factors play a dominant role in the epidemiology of melanoma and many other malignancies.

The expression of fibroblast growth factors and their receptors in the embryonic and neonatal mouse inner ear

Four different fibroblast growth factor receptors (FGFR) are known, three of which have splice variants (known as the b and c variants) in the FGF-binding domain, to give different patterns of sensitivity to the different FGFs. The expression of the b and c variants of the FGF receptors. together with the expression of the ligands FGF1. FGF2, FGF3, FGF7, FGF8b and FGF8c, was determined by quantitative reverse transcription-polymerase chain reaction in developing whole mouse inner ears, and in dissected components of the postnatal mouse inner ear. At embryonic age (E)10.5 days, when the otocyst is a simple closed sac, the receptor most heavily expressed was FGFR2b, relative to the postnatal day 0 level. Over the period E10.5-E12.5. during which the structures of the inner ear start to form, the expression of the different FGF receptors increased 10(2)-10(4) fold per unit of tissue, and there was a gradual switch towards expression of the 'c' splice variants of FGFR2 and FGFR3 rather than the 'b' variants. At E10.5, the ligands most heavily expressed, relative to the postnatal day 0 level, were FGF3, FGF8b and FGF8c. In the postnatal inner eat. the patterns of expression of receptors and ligands tended to be correlated, such that receptor variants were expressed in the same regions as the ligands that are known to activate them effectively. The neural/sensory region expressed high levels of FGFR3c, and high levels of the ligand FGF8b. The same area also expressed high levels of FGFR1b and FGFR2b, and high levels of FGF3. The lateral wall of the cochlea (including the stria vascularis and the spiral ligament) expressed high levels of FGFR1c and FGF1. 11 is suggested that the different FGF receptors and ligands are expressed in a spatially coordinated pattern to selectively program cochlear development. (C) 2001 Elsevier Science B.V. All rights reserved.

A critical comparison of the external and internal boron requirements for contrasting species in boron-buffered solution culture

Despite reports that boron (B) requirements differ among plant species there is a shortage of critical evidence to demonstrate unequivocally whether species differ in internal or external B requirements or both. The present research was conducted to establish the external and internal B requirements of three contrasting species, a woody dicot (marri), an herbaceous dicot (sunflower) and a monocot (wheat) using B-buffered solution culture. Boron-buffered solution culture provided satisfactory control of external B concentrations ranging from 0.04 to 30 muM throughout the 20- (sunflower and wheat) or 40-day (marri) growth period. At low external B concentrations (less than or equal to 0.13 muM), the growth of marri and sunflower was severely depressed but by contrast the vegetative growth of wheat plants was satisfactory and free of B deficiency symptoms. Marri and sunflower plants achieved total maximum shoot growth at greater than or equal to1.2 muM B in solutions while wheat plants did so at greater than or equal to 0.6 muM B. The critical B concentrations (mg kg(-1) dry matter) in the youngest open leaf blades of marri, sunflower and wheat plants were 17.9, 19.7 and 1.2 on 20, 10 and 10 days after transplanting (DAT), respectively. Lower internal and external B requirements of wheat were matched by a lower uptake rate of B compared to marri and sunflower.

Effect of hemochromatosis genotype and lifestyle factors on iron and red cell indices in a community population

Background: Heterozygotes for the C282Y mutation of the HFE gene may have altered hematology indices and higher iron stores than wild-type subjects. Methods: We performed a cross-sectional analysis of 1488 females and 1522 males 20-79 years of age drawn from the Busselton (Australia) population study to assess the effects of HFE genotype, age, gender, and lifestyle on serum iron and hematology indices. Results: Male C282Y heterozygotes had increased transferrin saturation compared with the wild-type genotype. Neither male nor female heterozygotes had significantly increased ferritin values compared with the wild-type genotype. Younger (20-29 years) wild-type males, but not heterozygous males, had significantly lower ferritin values than wild-type males in the older age groups. Compound heterozygous subjects had increased means for serum iron, transferrin saturation, corpuscular volume, and corpuscular hemoglobin compared with the wild-type genotype, and the males also had increased ferritin values (medians 323 vs 177 mug/L; P = 0.003). In both male and female wild-type subjects, an increased body mass index was associated with decreased serum iron and transferrin saturation and increased ferritin values. There was a significant increase in ferritin concentrations in both genders with increasing frequency of red meat consumption above a baseline of 1-2 times per week and alcohol intakes >10 g/day. Conclusions: Male C282Y heterozygotes had significantly increased transferrin saturation values. Compound heterozygous (C282Y/H63D) subjects formed a separate category of C282Y heterozygotes in whom both iron and red cell indices were significantly increased compared with the wild-type genotype. (C) 2001 American Association for Clinical Chemistry.

Urban birth and migrant status as risk factors for psychosis: An Australian case-control study

Background Urban birth and migrant status have been identified as risk factors for psychosis in North American and European studies. The aim of this study was to explore these variables in an Australian case-control study. Method Country of birth of subjects and their parents, and place of birth of Australian-born subjects, were examined in individuals with psychosis drawn from a prevalence study (n = 310) and well controls recruited from the same catchment area (n = 303). Results Migrant status was associated with a significantly decreased odds of having a psychotic disorder. For those born in Australia, neither migrant status of parents nor urban birth was associated with having a psychotic disorder. Conclusions The lack of effect for urban birth and second-generation migrant status may help generate candidate environmental risk factors that operate in Europe but not in Australia.

Mating behaviour and alternative oviposition sites for male eggs in the heteronomous hyperparasitoid Coccophagus gurneyi Compere (Hymenoptera : Aphelinidae)

The aphelinid parasitoid Coccophagus gurneyi Compere has unusual sex-related host relationships. Females are diploid and develop internally within mealybugs Pseudococcus calceolariae (Maskell). Males, in contrast, are haploid and hyperparasitic, developing on primary parasitoid larvae within the mealybugs. Furthermore, males have been claimed to be capable of either internal or external development, depending on the precise site of deposition of the haploid egg. This diversity of developmental pathways could indicate the existence of a sibling-species complex. We therefore quantified the mating and ovipositional behaviour of C. gurneyi, for comparison with that of an undescribed sibling species. We also checked whether the females deposit male eggs in alternative sites. The pattern of mating was found to be typical of mating behaviour in Coccophagus spp. and was consistent among all mating pairs, suggesting that the colony comprised one species. Further, the mating behaviour was significantly different from that of the undescribed sibling species. The site of male egg deposition varied and is apparently dictated by two factors; whether the mealybug is parasitised and, if so, the size of the parasitoid it contains. If the mealybugs were unparasitised or if the parasitoids within the mealybugs were small (< 0.53 mm), male eggs were deposited within the mealybug haemocoel. If the parasitoids were large (> 1.05 mm), male eggs were deposited within the parasitoids. These results support the claim of alternate host relationships and developmental pathways within males of C. gurneyi.

Factors influencing job valuation: a comparative study of critical care and mon-critical care nurses

This study sought to identify the relationship between three predictor variables. perceived collaboration with medical staff, autonomy and independent actions and an outcome. the value hospital nurses placed on their work. In total 189 critical care and 366 non-critical care nurses completed a mailed survey. Critical cure nurses perceived themselves to have a mure collaborative relationship with the medical staff. described performing actions independent of medical orders more frequently and perceived their jobs to have more value than non-critical care nurses. However the latter group perceived themselves to have more autonomy in their work. Within both groups collaboration and autonomy were significantly, but weak to moderately correlated with job valuation. Simply expanding the work hospital nurses do is unlikely to result in nurses valuing their jobs more. however promoting an environment of respect and sharing between the medical and nursing staff and supporting nurses when they act in an autonomous fashion may positively influence nurses' perceptions of their work. (C) 2001 Elsevier Science Ltd. All rights reserved.

Contingent attentional capture or delayed allocation of attention?

Under certain circumstances, external stimuli will elicit an involuntary shift of spatial attention, referred to as attentional capture. According to the contingent involuntary orienting account (Folk, Remington, & Johnston, 1992), capture is conditioned by top-down factors that set attention to respond involuntarily to stimulus properties relevant to one's behavioral goals. Evidence for this comes from spatial cuing studies showing that a spatial cuing effect is observed only when cues have goal-relevant properties. Here, we examine alternative, decision-level explanations of the spatial cuing effect that attribute evidence of capture to postpresentation delays in the voluntary allocation of attention, rather than to on-line involuntary shifts in direct response to the cue. In three spatial cuing experiments, delayed-allocation accounts were tested by examining whether items at the cued location were preferentially processed. The experiments provide evidence that costs and benefits in spatial cuing experiments do reflect the on-line capture of attention. The implications of these results for models of attentional control are discussed.

Pediculus humanus capitis infestations in the community: A pilot study into transmission, treatment and factors affecting control

Head lice (Pediculus humanus capitis) infestations affect schoolchildren worldwide, creating social, economic and health consequences for families. Problems with self-detection, chronic infestations and classroom transmission are compounded by increasing resistance of the lice to pediculicides. Public health strategies are based on limited research and little is known about transmission dynamics. Mismanagement and transmission in the general community are blamed for control failure. The purpose of this study was to explore community head-lice experience in Brisbane, Australia, and to identify critical factors underlying control failure. A home-based pilot survey used physical examination to verify transmission and treatment patterns which were self-reported by a group of trace-contact families in addition to other unconnected participants. The survey was enlarged to further compare therapy outcomes and suspected risk factors. The findings reinforce those of previous studies - that children attending school and early childhood centres, and subsequently their families, are most at risk of contracting pediculosis capitis, and some may carry lice for years. First-line (pediculicidal) treatment and even additional physical methods of hand-picking and fine-toothed combing usually fail to eradicate lice quickly and completely (overall cure-rate 39 per cent, n = 84 cases). Failures were linked to hair characteristics. Public education alone may not control pediculosis. Accurate diagnosis requires considerable experience; a strong case exists for returning to institutional surveillance.

The investigation of factors underlying deficits in self-awareness and self-regulation

Primary objective: To examine a theoretical model which suggests that a contribution of both psychological and neuropsychological factors underlie deficits in self-awareness and self-regulation. Research design: Multivariate design including correlations and analysis of variance (ANOVA). Methods: Sixty-one subjects with acquired brain injury (ABI) were administered standardized measures of self-awareness and self-regulation. Psychological factors included measures of coping-related denial, personality-related denial and personality change. Neuropsychological factors included an estimate of IQ and two measures of executive functioning that assess capacity for volition and purposive behaviour. Main outcomes and results: The findings indicated that the relative contribution of neuropsychological factors to an outcome of deficits in self-awareness and self-regulation had a more direct effect than psychological factors. In general, measures of executive functioning had a direct relationship, while measures of coping-related and personality-related denial had an indirect relationship with measures of self-awareness and self-regulation. Conclusion: The findings highlighted the importance of measuring both neuropsychological and psychological factors and demonstrated that the relative contribution of these variables varies according to different levels of self-awareness and self-regulation.