Mercury toxicity induces oxidative stress in growing cucumber seedlings

In this study, the effects of exogenous mercury (HgCl(2)) on time-dependent changes in the activities of antioxidant enzymes (catalase and ascorbate peroxidase), lipid peroxidation, chlorophyll content and protein oxidation in cucumber seedlings (Cucumis sativus L.) were investigated. Cucumber seedlings were exposed to from 0 to 500microM of HgCl(2) during 10 and 15 days. Hg was readily absorbed by growing seedlings, and its content was greater in the roots than the in shoot. Time and concentration-dependent reduction in root and shoot length was observed at all concentrations tested, equally in the roots and shoot, at both 10 and 15 days. At 50microM HgCl(2), root fresh weight of 15-day-old seedlings increased, and at other concentrations, it reduced. For 10-day-old seedlings, reduction in root and shoot fresh biomass was observed. At 15 days, only at 50microM HgCl(2) was there no observed reduction in shoot fresh biomass. Dry weight of roots increased at 500microM both at 10 and 15 days, though at 250microM HgCl(2) there was only an increase at 15 days. There was a significant effect on shoot dry weight at all concentrations tested. Hg-treated seedlings showed elevated levels of lipid peroxides with a concomitant increase in protein oxidation levels, and decreased chlorophyll content when exposed to between 250 and 500microM of HgCl(2). At 10 days, catalase activity increased in seedlings at a moderately toxic level of Hg, whereas at the higher concentration (500microM), there was a marked inhibition. Taken together, our results suggest that Hg induces oxidative stress in cucumber, resulting in plant injury.     

Mesomelic campomelia,polydactyly and Dandy–Walker cyst in siblings

The present report describes two fetuses, one female and one male, with thus far undescribed skeletal malformations. The mother was a gravida 2, para 0. Both pregnancies were terminated in the second trimester because of multiple congenital anomalies diagnosed ultrasonographically resembling a short rib-polydactyly syndrome. Both fetuses were found to have postaxial hexadactyly of the hands and feet, marked bilateral campomelia of the forearm and shank bones, and a Dandy–Walker cyst. In addition, the fourth ventricle was dilated in the first sibling and the second sibling had an inverse intestinal malrotation. A literature search failed to reveal similar observations. Copyright © 2001 John Wiley & Sons, Ltd.     

Disasters and development in agricultural input markets: bean seed markets in Honduras after Hurricane Mitch

The bulk of developing countries' populations and poor depend on agriculture for food and income. While rural economies and people are generally the most severely affected by natural disasters, little is known about how disasters and subsequent relief activities affect agricultural markets with differing levels of development. The article addresses this gap, drawing evidence from bean seed markets in Honduras after Hurricane Mitch. Case studies are used to address hypotheses about a disaster's effects on supply and demand in seed markets, farmers' responses and the performance of relief interventions in markets showing differing levels of development. The results show the importance of tailoring relief interventions to the markets that they will affect and to the specific effects of a disaster; the potential to use local and emerging seed distribution channels in a relief intervention; and opportunities for relief activities to strengthen community seed systems.     

Prenatal diagnosis in Coffin-Lowry syndrome demonstrates germinal mosaicism confirmed by mutation analysis

Coffin-Lowry syndrome is a rare X-linked, semi-dominant mental retardation syndrome resulting from mutations of the ribosomal S6 kinase 2 (RSK2) gene. In the present report, a male patient affected with Coffin-Lowry syndrome is shown to have a nonsense mutation of the RSK2 gene. His unaffected mother does not have this mutation in her lymphocytes. In her third pregnancy prenatal diagnosis by mutation analysis has detected gonadal mosaicism. As this is the second report of germinal mosaicism in Coffin-Lowry syndrome, the finding has important implication for genetic counselling. Copyright © 2001 John Wiley & Sons, Ltd.     

Flow control regulations to gain waste disposal self sufficiency

In a recent ruling, the U.S. Supreme Court has determined that solid waste flow control regulations are unconstitutional. Many states have established some form of flow control. As an example, the state of New Jersey has implemented a long-term plan to gain waste disposal self-sufficiency by the year 2000. The success of this plan hinges on the flow controls implemented by the state. Almost two billion U.S. dollars of debt has been incurred by the twenty-two solid waste districts in New Jersey to build the state-of-the-art facilities necessary to reach these goals. An analysis has been performed on the most recent data available of the state’s solid waste generation and management system, at a time when New Jersey must restructure its solid waste management plan. The New Jersey solid waste management model is of interest to other states. The consequences, facts, and alternatives of flow control are examined.     

Catalytic effect of natural clays on properties and chemical structure of recycled polyethylene

Journal of Material Cycles and Waste Management - Montmorillonite clays such as bentonites are often studied and used as reinforcement to thermoplastics, since it can generate nanostructures,...     

Household waste generation,composition and determining factors in rapidly urbanizing developing cities: case study of Santa Cruz de la Sierra,Bolivia

Journal of Material Cycles and Waste Management - Detailed information about waste generation rates, composition, and their influencing factors, is essential for sustainable municipal solid waste...