Photoinhibition in differently coloured juvenile leaves of Syzygium species

Photoinhibition, as measured by the dark-adapted chlorophyll a fluorescence ratio F-v/F-m, was assessed in Syzygium moorei, a species with dark green juvenile leaves, Syzygium corynanthum, which has light green juvenile leaves, and two species with pink-red juvenile leaves (Syzygium wilsonii and Syzygium luehmannii). All plants were glasshouse-grown (maximum PPFD 1500 mu mol m(-2) s(-1)) under optimum nutrition and water. When measured at midday, dark-adapted F-v/F-m ratios of juvenile leaves gradually increased in art species as percentage of full leaf expansion (% FLE) increased. Fluorescence measurement 3 h after sunset or pre-dawn also showed a developmental effect on F-v/F-m, with juvenile leaves of S, luehmannii and S. wilsonii showing much lower F-v/F-m at all stages of development. Dark-adapted F-v/F-m values in both juvenile and mature leaves generally never exceeded 0.8 at any stage in any of the species. Courses of F-v/F-m on sunny days showed greater diurnal photoinhibition in green juvenile (c, 50% FLE) leaves of S, moorei (24%) and S, corynanthum (36%) than in mature leaves of the previous flush in these species (<10%), Diurnal photoinhibition was statistically similar (18-24%) in pink-red juvenile and green mature leaves of S, luehmannii and S, wilsonii. Re-positioning juvenile leaves of S, wilsonii horizontally increased diurnal photoinhibition, Exposure of leaves to a standard mild photoinhibitory right treatment (30 min at 1000 mu mol m(-2) s(-1)) showed that juvenile leaves of air species had a lower percentage of high energy state quenching (qE) and a higher percentage of photoinhibitory quenching (ql) than mature leaves.

Juvenile helping behaviour in the Dusky Moorhen, Gallinula tenebrosa

In Dusky Moorhens, Gallinula tenebrosa, helping behaviour maybe displayed by juveniles when groups contain offspring of different age classes. We investigated the frequency and amount of parental care provided by juvenile moorhens to younger siblings from subsequent same-year broods. In some social groups, juveniles provided up to 33% of the total number of feeds provided to chicks. Juveniles were observed to feed chicks when as young as six weeks of age, often while still receiving food from adults themselves. Low within-group relatedness and low reproductive costs associated with juvenile helping have important consequences for the cost-benefit ratio of helping behaviour in this species.

The effectiveness of splinting as perceived by the parents of children with Juvenile Ideopathic Arthritis

Juvenile idiopathic arthritis (JIA) is an important disease of childhood with farreaching effects on the child and family. Splinting is a major treatment modality used by occupational therapists for children with JIA. Parents play a central role in whether, when and how splints are used with their children on a daily basis. This paper describes a qualitative research project, which was undertaken to evaluate an occupational therapy service for children with JIA whose treatment had involved splinting. Using semi-structured interviews, the study investigated five mothers' perceptions of the effectiveness of splinting for their children. The interviews revealed five major points. First, the informants generally believed the splinting to be effective. Secondly, the children involved generally resisted wearing splints because they were physically uncomfortable and made them feel different to other children. Thirdly, the mothers used a variety of strategies to ensure that their children wore the splints. Fourthly, the perception of having a positive and supportive relationship with the therapist enhanced the mothers' ability to adhere to splinting. Lastly, the mothers' grief at having a child with JIA influenced their ability to understand and attend to information about specific interventions such as splinting. Practical responses to these findings are outlined.

The effects of temperature on the growth, survival and biomass of different families of juvenile Penaeus japonicus Bate

Variation in the growth, survival and change in total biomass (termed biomass increase) of different families of juvenile Penaeus japonicus was investigated over a range of temperatures in controlled laboratory experiments. In the first experiment, the effects of temperature on six families of juveniles were examined over a broad range of temperatures (24 to 30 degreesC). In the second experiment, the effects of temperature on six more families of juveniles were examined over a narrower range of temperatures (27.5 to 31.2 degreesC). Over the broad temperature range, mean growth and biomass increase were highest at 27 degreesC and mean survival was highest at 24 degreesC. Mean growth was lowest at 24 degreesC, whilst survival and biomass increase were lowest at 30 degreesC. However, there was a significant interaction between family and temperature, with some families tolerating a broader range of temperatures than others. As a result, the ranking of families in relation to growth, survival and biomass increase changed at each temperature. This effect was more pronounced for survival than for growth. Over the narrower range, temperature significantly affected growth, survival and biomass increase, but there was no significant interaction between family and temperature. Growth, survival and biomass increase were significantly lower at 31.2 than at 27.5 and 29.2 degreesC. These results suggest that if grow-out conditions for P. japonicus vary by more than a few degrees, interactions between family and temperature could affect the efficiency of selection. The results also suggest that the family x temperature interaction may have a more pronounced effect on survival than on growth. Crown Copyright (C) 2002 Published by Elsevier Science B.V. All rights reserved.

Functional assessment tools for paediatric clients with Juvenile Chronic Arthritis: An update and review for occupational therapists

Juvenile chronic arthritis (JCA) is one cause of chronic illness and disability in childhood. Traditional clinical assessment of clients with JCA include objective measures of joint deformity, joint swelling, range of motion, duration of morning stiffness, pain, walking speed, running speed and muscle strength. In many instances, these traditional measures have little or no significance or relevance to paediatric clients and their parents whereas functional skills used in everyday living are more likely to be meaningful. Measures of physical, social, and psychological functioning ensure a comprehensive health assessment. Responsible occupational therapy assessment and management of paediatric clients diagnosed with JCA requires the use of reliable, valid and sensitive measures of function. Several instruments are now available which measure a child's or adolescent's functional abilities. In this paper, JCA and the impact of JCA on functional development are reviewed. As well, seven functional assessment tools designed for use with paediatric clients with JCA which occupational therapists can use in their clinical practice will be appraised. The various characteristics of these tools are discussed in order to assist practitioners and researchers in selecting the functional instrument which best meets their needs.

Pulse-exposure effects of selected insecticides to juvenile Australian crimson-spotted rainbowfish (Melanotaenia duboulayi)

Laboratory toxicity studies were conducted in southeastern Queensland, Australia, to determine the acute lethal effects of a 1-h pulse exposure of selected insecticides to adult and juvenile (