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Biomedical subjects

K S Bawa

Publications and source records attributed to K S Bawa.

5 recordsLinked to original sources

Population growth, human development, and deforestation in biodiversity hotspots.

Human population and development activities affect the rate of deforestation in biodiversity hotspots. We quantified the effect of human population growth and development on rates of deforestation and analyzed the relationship between these causal factors in the 1980s and 1990s. We compared the averages of population growth, human development index (HDI, which measures income, health, and education), and deforestation rate and computed correlations among these variables for countries that contain biodiversity hotspots. When population growth was high and HDI was low there was a high rate of deforestation, but when HDI was high, rate of deforestation was low, despite high population growth. The correlation among variables was significant for the 1990s but not for the 1980s. The relationship between population growth and HDI had a regional pattern that reflected the historical process of development. Based on the changes in HDI and deforestation rate over time, we identified two drivers of deforestation: policy choice and human-development constraints. Policy choices that disregard conservation may cause the loss of forests even in countries that are relatively developed. Lack of development in other countries, on the other hand, may increase the pressure on forests to meet the basic needs of the human population. Deforestation resulting from policy choices may be easier to fix than deforestation arising from human development constraints. To prevent deforestation in the countries that have such constraints, transfer of material and intellectual resources from developed countries may be needed. Popular interest in sustainable development in developed countries can facilitate the transfer of these resources.

Animals↗

Neurocysticercosis--New Millennium, ancient disease and unending debate.

A spurt of cases of Neurocysticercosis (NCC) at our department reopened the debate on whether to treat or not and spurred us on to review the available literature for a viable solution. Despite the disease having been around for centuries a cogent treatment plan eludes us even as other ancient scources have been successfully engaged. Neurocysticercosis presents a peculiar problem as it is an end-stage infection, accidental in man, with a benign natural course and would have merited considerably less attention, had it not chosen to infest the brain. These unique and characteristic features are the fundamental reasons why so many different treatment strategies are continuously proffered; many or none seem to work, depending on the viewpoint. And the target organs of this otherwise unglamorous tapeworm cyst--the brain, eye and spinal cord-ensure that there is always pressure, and temptation to treat rather than let it be, even if the weight of evidence is to the contrary. An overview of the history of the disease and the most recent happenings is presented here, in which these issues are reviewed with special attention to the debate on treatment. From the facts that emerge, an attempt has been made to present a workable plan that would help practicing pediatricians in treating most encountered cases till such time we hear the last word on the issue.

Albendazole↗

The effect of ecological factors on the mating system of a South American shrub species (Helicteres brevispira).

Mating systems are influenced by several ecological factors, including plant density, number of flowers per plant, and pollinator movements. In this study, we investigated the simultaneous effects of these three factors on the mating system of a self-compatible Brazilian shrub species: Helicteres brevispira St. Hil. Outcrossing rate is directly correlated with plant density. Changes in the number of flowers per plant affect outcrossing rate through their effect on the density of flowers. Variation in foraging behaviour of hummingbird pollinators is a consequence of the interaction between plant density and number of flowers per plant. Territorialist pollinators are common in high density areas but visit few flowers on each plant, thereby promoting outcrossing. In areas of low plant density, trapliners and rare territorialists visit several flowers per plant, thus increasing selfing. Our results indicate that outcrossing rate is a dynamic parameter, with the extent of variation depending on a number of ecological factors. In successional species such as those in the genus Helicteres, demographic changes may be accompanied by alterations in mating system parameters, with concomitant effects on the genetic structure of populations.

Crosses, Genetic↗