Seasonal levels of serum vitellogenin and oocyte growth in the channel catfish Ictalurus punctatus

Seasonal levels of serum vitellogenin (VG) were measured in adult and juvenile (10–30 months old) female channel catfish using an enzyme-linked immunosorbent assay (ELISA). In adults sampled during a 2-year period, the highest mean (±s.e.) VG level was 30.21 ± 5.36 mg/ml in May before spawning and declined to 3.79 ± 0.89 mg/ml in June after the fish had spawned. Oocyte diameter increased from September to November, remained the same until February, then increased again until maximum mean diameter of 2356 ± 49 μm was measured in May. Vitellogenin was detected in the serum of juvenile fish that were 12 months old, but yolk granules were not visible in hematoxylin and eosin stained sections of oocytes until the fish were 18 months old. Mean serum VG levels of juvenile fish were lower than the adults, and no VG peak was observed in the juvenile fish. Vitellogenin was present in the serum throughout the year in adult fish and in juveniles older than 12 months.     

Food poverty and health among schoolchildren in Ireland: findings from the Health Behaviour in School-aged Children (HBSC) study

OBJECTIVES: To investigate the relationships between food poverty and food consumption, health and life satisfaction among schoolchildren. DESIGN: Analysis of the 2002 Health Behaviour in School-aged Children (HBSC) study, a cross-sectional survey that employs a self-completion questionnaire in a nationally representative random sample of school classrooms in the Republic of Ireland. SUBJECTS: A total of 8424 schoolchildren (aged 10-17 years) from 176 schools, with an 83% response rate from children. RESULTS: Food poverty was found to be similarly distributed among the three social classes (15.3% in the lower social classes, 15.9% in the middle social classes and 14.8% in the higher social classes). It was also found that schoolchildren reporting food poverty are less likely to eat fruits, vegetables and brown bread, odds ratio (OR) from 0.66 (95% confidence interval (CI) 0.45-0.87) to 0.81 (95% CI 0.63-0.99); more likely to eat crisps, fried potatoes and hamburgers, OR from 1.20 (95% CI 1.00-1.40) to 1.62 (95% CI 1.39-1.85); and more likely to miss breakfast on weekdays, OR from 1.29 (95% CI 0.33-1.59) to 1.72 (95% CI 1.50-1.95). The risk of somatic and mental symptoms is also increased, OR from 1.48 (95% CI 1.18-1.78) to 2.57 (95% CI 2.33-2.81); as are negative health perceptions, OR from 0.63 (95% CI 0.43-0.83) to 0.52 (95% CI 0.28-0.76) and measures of life dissatisfaction, OR from 1.88 (95% CI 1.64-2.12) to 2.25 (95% CI 2.05-2.45). Similar results were found for life dissatisfaction in an international comparison of 32 countries. All analyses were adjusted for age and social class. CONCLUSIONS: Food poverty in schoolchildren is not restricted to those from lower social class families, is associated with a substantial risk to physical and mental health and well-being, and requires the increased attention of policy makers and practitioners.     

WetUp: a software tool to display approximate wetting patterns from drippers

Knowledge of the wetted perimeter of soil arising from infiltration of water from trickle irrigation drippers is important in the design and management of efficient systems. A user-friendly software tool, WetUp, has been developed to help highlight the impact of soils on water distribution in trickle-irrigated systems. WetUp determines the approximate radial and vertical wetting distances from an emitter in homogeneous soils calculated using analytical methods, and then uses an elliptical plotting function to approximate the expected wetted perimeter. In this paper we describe WetUp and use examples to demonstrate how it can be applied. We also compare the wetted perimeter predicted using WetUp with that predicted by other methods. Results show that the wetting pattern is well described by the ellipsoidal approximation for slowly permeable soils, but that it tends to underestimate the radial wetting in highly permeable soils, particularly as the volume of applied water increases. The error is, however, small in most cases, and of minimal concern when applying WetUp to illustrate the important role that soil hydraulic properties play in determining wetting patterns.Communicated by J. Annandale     

Who eats four or more servings of fruit and vegetables per day? Multivariate classification tree analysis of data from the 1998 Survey of Lifestyle, Attitudes and Nutrition in the Republic of Ireland

OBJECTIVE: To identify, using the novel application of multivariate classification trees, the socio-economic, sociodemographic and health-related lifestyle behaviour profile of adults who comply with the recommended 4 or more servings per day of fruit and vegetables. DESIGN: Cross-sectional 1998 Survey of Lifestyle, Attitudes and Nutrition. SETTING: Community-dwelling adults aged 18 years and over on the Republic of Ireland electoral register. SUBJECTS: Six thousand five hundred and thirty-nine (response rate 62%) adults responded to a self-administered postal questionnaire, including a semi-quantitative food-frequency questionnaire. RESULTS: The most important determining factor of compliance with the fruit and vegetable dietary recommendations was gender. A complex constellation of sociodemographic and socio-economic factors emerged for males whereas the important predictors of 4 or more servings of fruit and vegetable consumption among females were strongly socio-economic in nature. A separate algorithm was run to investigate the importance of health-related lifestyle and other dietary factors on compliance with the fruit and vegetable recommendations. Following an initial split on compliance with dairy recommendations, a combination of non-dietary behaviours showed a consistent pattern of healthier options more likely to lead to compliance with fruit and vegetable recommendations. There did, however, appear to be a compensatory element between the variables, particularly around smoking, suggesting the non-existence of an exclusive lifestyle for health risk. CONCLUSIONS: Material and structural influences matter very much for females in respect to compliance with fruit and vegetable recommendations. For males, while these factors are important they appear to be mediated through other more socially contextual-type factors. Recognition of the role that each of these factors plays in influencing dietary habits of men and women has implications for the manner in which dietary strategies and policies are developed and implemented.