Public mosquito abatement

One can say very little about the relative merits of temporary versus permanent salt marsh mosquito control from the Carlson and DeBord study (J. Environ. Econ. Manag. 3, 142–153 (1976)). Their conclusion that temporary control is more cost effective than permanent control is suspect because of their interpretation and use of the data which entered their analyses and because of their interpretation of analytical results.     

Distribution of lindane in plasma and brain after a single administration to cats

The distribution of lindane and its metabolites in the plasma and brain of the cats after 30 minutes, 1, 2, 4 and 8 hours of administration of lindane (2mg/kg, i.v.) was investigated. The compound distributes differentially in the CNS and this pattern changes with time. The pattern of distribution shows that although lindane concentration is higher in areas with a high myelin content, it disappears more rapidly from gray matter. The plasma levels were also high at 30 minutes interval and then gradually decreased. The rate of formation of the metabolite 2,4,6‐Trichlorophenol appeared to be maximum in the first 4 hours. The accumulation of the compound and its metabolite in brain during the experimental period was not evident.     

Chaos and complexity in development

SUMMARY

The paper outlines some main features of chaos theory. Examples of chaotic systems in society and the environment are given. Spontaneous interaction of components, without being planned or directed, is known as ‘self-organising behaviour’. Chaos is an essential aspect of this self organisation, occurring in many forms. A chaotic system is defined as one that shows sensitivity to initial conditions. If the errors relative to the initial conditions become too great, the system will eventually collapse. Development projects are sensitive to such initial conditions. In particular, two examples in development are outlined in some detail and commented upon. One is the occurrence of a project promoting self-organising systems among the poorest of the poor. The other outlines how rehabilitation after resettlement in a power project has transgressed the ‘edge of chaos’ socio-emotionally, in spite of the socioeconomic development being good.     

Occupational injury and accident research: A comprehensive review

In this paper, a comprehensive review of the concepts of occupational injury and accident causation and prevention is presented. Starting with hazard identification, the issues on risk assessment, accident causation, and intervention strategies are discussed progressively. The distinctiveness and overlaps in accident and injury research are highlighted. Both empirical research in terms of hypotheses tested and theoretical research such as accident causation models are compared and contrasted. Finally, based on the critical appraisal of the comprehensive review, future research directions on occupational injury research are delineated.     

A study on abundance and distribution of mangrove species in Indian Sundarban using remote sensing technique

Conservation and management of Sundarban mangrove forest is difficult chiefly due to inaccessibility and hostile condition. Remote sensing serves as an important tool to provide up-to date baseline information which is the primary requirement for the conservation planning of mangroves. In this study, supervised classification by maximum likelihood classifier (MLC) has been used to classify LANDSAT TM and LANDSAT ETM satellite data. This algorithm is used for computing likelihood of unknown measurement vector belonging to unknown classes based on Bayesian equation. Image spectra for various mangrove species were also generated from hyperspectral image. During field visits, GPS locations of five dominant mangrove species with appreciable distribution were taken and image spectra were generated for the same points from hyperion image. The result of this classification shows that, in 1999 total mangrove forest accounted for 55.01 % of the study area which has been reduced to 50.63 % in the year 2010. Avicennia sp. is found as most dominating species followed by Excoecaria sp. and Phoenix sp. but the aerial distribution of Avicennia sp., Bruguiera sp. and Ceriops sp. has reduced. In this classification technique the overall accuracy and Kappa value for 1999 and 2010 are 80 % and 0.77, 85.71 % and 0.81 respectively.     

Science–policy processes for transboundary water governance

In this policy perspective, we outline several conditions to support effective science–policy interaction, with a particular emphasis on improving water governance in transboundary basins. Key conditions include (1) recognizing that science is a crucial but bounded input into water resource decision-making processes; (2) establishing conditions for collaboration and shared commitment among actors; (3) understanding that social or group-learning processes linked to science–policy interaction are enhanced through greater collaboration; (4) accepting that the collaborative production of knowledge about hydrological issues and associated socioeconomic change and institutional responses is essential to build legitimate decision-making processes; and (5) engaging boundary organizations and informal networks of scientists, policy makers, and civil society. We elaborate on these conditions with a diverse set of international examples drawn from a synthesis of our collective experiences in assessing the opportunities and constraints (including the role of power relations) related to governance for water in transboundary settings.     

An innovative sustainability assessment for urban wastewater infrastructure and its application in Chengdu, China

Sustainability assessments are an increasingly common tool for measuring progress towards sustainable development. Despite their popularity, sustainability assessments and the indicators that compose them are said to have had little impact on the policy arena. In this paper we discuss four attributes that we contend will improve the use of sustainability assessments to guide decision making: non-compartmentalization, site specificity, built-in guidance for target setting, and ability to measure active sustainability. We present a novel assessment tool for wastewater treatment infrastructure that illustrates these attributes. The assessment is composed of two-dimensional indicators we call “burden to capacity” ratios, that reveal and quantify the local value of resources embodied in wastewater and treatment byproducts, and the tradeoffs between designing systems for disposal versus reuse. We apply the sustainability assessment framework to an existing treatment plant in Chengdu, China and discuss the results.     

Prenatal exclusion of duchenne muscular dystrophy by fetal muscle biopsy

A fetal thigh muscle biopsy was performed at 18 weeks and 6 days' gestation using an automatic 18-gauge biopsy needle. A positive immunoreaction with antisera to the amino- and carboxy-terminals of dystrophin excluded Duchenne muscular dystrophy from this at-risk male.     

Nitrate pollution of wells: pollution prevention policy options

Irrigated agriculture is a major sector of agricultural economy where high value crops are grown with substantial input of fertilizers and pesticides. High concentrations of nitrate and pesticides have been observed in ground water beneath irrigated areas in humid regions, where irrigation is practiced on sandy soils that have low water-holding capacity. Data from these areas indicate that irrigation wells are typically screened in the bottom part of the aquifer (which contain coarser deposits) whereas the domestic wells are screened just below the water table. Monitoring results from several irrigated areas have shown the stratification of dissolved inorganic and organic chemicals in the aquifer. Nitrate in such systems is typically highest near the surface. This has serious health implications for the rural population that relies upon shallow ground water for drinking. Current environmental policy towards pollution reduction focuses on improved management practices to reduce the loading of the chemicals to ground water. However, an engineering issue, dealing with the design of the irrigation and domestic wells has not been addressed. A design modification for the irrigation and domestic wells can reduce the risk of high nitrate ground water being pumped by domestic wells. A proposal to convert a deep vertical irrigation well to a series of small-capacity shallow vertical wells or a large-capacity horizontal well and slight deepening of the domestic wells was examined through simulations. This can reduce the nitrate concentration of ground water in domestic wells dramatically and use the high nitrate water for crop irrigation.