Patterns of tree growth in relation to environmental variability in the tropical dry deciduous forest at Mudumalai, southern India.

Tree diameter growth is sensitive to environmental fluctuations and tropical dry forests experience high seasonal and inter-annual environmental variation. Tree growth rates in a large permanent plot at Mudumalai, southern India, were examined for the influences of rainfall and three intrinsic factors (size, species and growth form) during three 4-year intervals over the period 1988-2000. Most trees had lowest growth during the second interval when rainfall was lowest, and skewness and kurtosis of growth distributions were reduced during this interval. Tree diameter generally explained less than 10% of growth variation and had less influence on growth than species identity or time interval. Intraspecific variation was high, yet species identity accounted for up to 16% of growth variation in the community. There were no consistent differences between canopy and understory tree growth rates; however, a few subgroups of species may potentially represent canopy and understory growth guilds. Environmentally-induced temporal variations in growth generally did not reduce the odds of subsequent survival. Growth rates appear to be strongly influenced by species identity and environmental variability in the Mudumalai dry forest. Understanding and predicting vegetation dynamics in the dry tropics thus also requires information on temporal variability in local climate.

Prognosis in children with head injury: an analysis of 340 patients.

BACKGROUND: The outcome in children with head injury is distinctive because of the different biophysical properties of the child's skull and brain, and their reaction to injury. METHODS: In this retrospective study of three hundred and forty children with head injury, managed from January 1993 to December 1998, at NIMHANS, the factors influencing outcome were analyzed. RESULTS: On admission there were 40 children in GCS 3-5, 55 children in GCS 6-8, 96 in GCS 9-12 and 152 children in GCS 13-15. Eleven patients were under 2 years of age, 53 were between 3-5 years, 140 were between 6-10 years and 156 were between 11-15 years of age. The prognosis in various intracranial pathologies due to head injury was evaluated and outcome assessed at discharge. There were 95 children with EDH and 8.4% had poor outcome (vegetative state or death). There were 85 patients with contusion and poor outcome was noted in 18.8%. One hundred patients had diffuse cerebral oedema on CT scan and outcome was poor in 25% of these patients. The clinical features associated with poor prognosis were, absence of ocular movements (50%), abnormal pupillary size and reaction (49%) and age less than 2 years (27%).