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Introduction: An innovative frugal technology that has recently been reported with positive short-term clinical outcomes is the use of sterilised mosquito net as an alternative to commercial hernia meshes. However, long-term clinical data supporting the use of this mesh is lacking. Methods: A ten year retrospective analysis of consecutive patients undergoing inguinal hernia repair using Low Density PolyEthylene (LDPE) mesh with 12-18 months follow up. Results: During the study period 713 inguinal hernia repairs were performed using low cost polyethylene mesh in 651 patients. Thirty-two patients were lost to follow up. There were six superficial surgical site infections (0.9%), one seroma (0.1%), two patients who experienced chronic pain (0.3%), and two hematomas (0.3%). There were no recurrences or cases of mesh rejection. Discussion: The results of this retrospective study confirm the long-term safety and effectiveness of the use of LDPE mosquito net mesh for inguinal hernioplasty.

Particulate matter collected at 732 and 2914 m during a time-series sediment trap experiment (sampling interval 13 days) in the Central Arabian Sea (14°29′N, 64°46′E; water depth 4016 m) was analysed for its fatty acid and organic carbon contents. The sampling period covered the summer monsoon of 1986. Contents of organic carbon and fatty acid decrease with increasing particle fluxes. At 732 m fatty acids account for 0.6–4% of organic carbon. Particulate organic matter collected during high-productivity and high-flux periods exhibits signs of less intense degradation within the surface layers. Furthermore, loss rates of organic carbon and fatty acids between 732 and 2914 m increase with increasing particle flux, which suggests that water column degradation is intensified during this period. Selective degradation of fatty acids diminishes their contribution to organic carbon in the deeper trap (0.3–0.7%). Despite this, the seasonality in fatty acid flux is maintained down to the deep ocean. Differences in fatty acid composition between the two depths are indicative of the organisms involved in the degradation of particulate organic matter in the water column, especially bacteria. Biological alteration of sinking particulate matter appears to occur mainly on particles.

Often, as a frantic response to problems of water scarcity and consequent hardships faced by both urban and communities, India has invested heavily in rainwater harvesting. Unlike investment in large water resource systems, these efforts, by and large, lack hydrological planning and sound economic analysis: research on the impact of local water harvesting/groundwater recharge activities in India is very sparse. This paper identifies sex critical issues in rainwater harvesting efforts in water-scarce regions of India. First: there is no emphasis on potential local supplies and the demand they have to cater for: local supply potential is low in most water scarce regions, a fact compounded by poor reliability, and demand far exceeds the supply potential. Second: there are complexities in the economic evaluation of RWH, due to lack of scientific data on inflows, runoff collection and storage efficiency, beneficiaries, value of the incremental benefits generated and scale considerations. With higher degrees of basin development, the marginal benefit from water harvesting at the basin level reduces, while marginal cost increases. Third: in many basins, there is a strong ‘trade-off’ between maximizing hydrological benefits and improving cost effectiveness. Fourth: many water-scarce basins are characterized by wide disparity in demand between upper catchments and lower catchments, so that there is a trade-off in maximizing benefits of upstream water harvesting with optimizing basin-wide benefits. Fifth: in many water-scarce basins, local water harvesting merely divides the hydrological benefits rather than augmenting them. Finally, poor integration between surface water and groundwater systems, and lack of inclusion of natural recharge, ultimately leads to reduction in potential for artificial recharge in hard rock areas.

Often, as a frantic response to problems of water scarcity and consequent hardships faced by both urban and communities, India has invested heavily in rainwater harvesting. Unlike investment in large water resource systems, these efforts, by and large, lack hydrological planning and sound economic analysis: research on the impact of local water harvesting/groundwater recharge activities in India is very sparse. This paper identifies sex critical issues in rainwater harvesting efforts in water-scarce regions of India. First: there is no emphasis on potential local supplies and the demand they have to cater for: local supply potential is low in most water scarce regions, a fact compounded by poor reliability, and demand far exceeds the supply potential. Second: there are complexities in the economic evaluation of RWH, due to lack of scientific data on inflows, runoff collection and storage efficiency, beneficiaries, value of the incremental benefits generated and scale considerations. With higher degrees of basin development, the marginal benefit from water harvesting at the basin level reduces, while marginal cost increases. Third: in many basins, there is a strong ‘trade-off’ between maximizing hydrological benefits and improving cost effectiveness. Fourth: many water-scarce basins are characterized by wide disparity in demand between upper catchments and lower catchments, so that there is a trade-off in maximizing benefits of upstream water harvesting with optimizing basin-wide benefits. Fifth: in many water-scarce basins, local water harvesting merely divides the hydrological benefits rather than augmenting them. Finally, poor integration between surface water and groundwater systems, and lack of inclusion of natural recharge, ultimately leads to reduction in potential for artificial recharge in hard rock areas.

Die Geowissenschaften

9-methoxy-N2-methylellipticinium acetate (MMEA) is representative of a series of quaternized ellipticine derivatives that are selectively cytotoxic to human brain tumor cell lines derived from non-neuronal (glial) cells (Acton et al, 1994). In an attempt to determine whether MMEA may exhibit toxicity to normal brain cells, we have examined the effect of the drug, in vitro, using sagittal slices of rat brain. Incubation of rat brain slices in an artificial cerebrospinal fluid medium containing MMEA resulted in dose-dependent leakage of lactate dehydrogenase (LDH) into the surrounding medium. However, other subcellular marker enzymes such as Na(+)-K+ATPase (plasma membrane), cytochrome c oxidase, isocitrate dehydrogenase, NADH-dehydrogenase (mitochondrial), N-acetylglucosaminidase, acid phosphate (lysosomal), glyceraldehyde-3-phosphate dehydrogenase and enolase (glycolytic enzymes) were unaffected even at the highest tested concentrations of MMEA (10 and 100 microM). Preincubation of slices with reserpine (1 nM) or, dopamine or serotonin-specific reuptake inhibitors abolished MMEA-induced toxicity in brain slices. Pretreatment of slices with piperonyl butoxide and metyrapone, inhibitor of cytochrome P-450, also prevented the toxicity of MMEA. Further, brain slices prepared from phenobarbital-treated rats showed enhanced sensitivity to MMEA; significant leakage of LDH was observed at MMEA concentrations as low as 1 nM. The present studies demonstrate the toxicity of MMEA in rat brain slices, in vitro, and suggest a role for brain cytochrome P-450 in the neurotoxicity of MMEA [corrected].