Sulfate disinfection, stabilisation and heavy metal removal from sewage sludge – process description and preliminary results

A new, closed loop process for the disinfection, stabilisation and removal of heavy metal from sewage sludge (consisting of a sludge/sulfuric acid reactor, hybrid H2S generator and H2S bioscrubber) is described. Preliminary results for total solids (TS), volatile suspended solids (VSS), chemical oxygen demand (COD), acetate and propionate destruction in the hybrid H2S generator have shown that digestion efficiency is not compromised in a hybrid reactor generating H2S compared to a methanogenic reactor. 70% of the electron flow in the hybrid H2S generator was diverted to methane at a COD:SO4 ratio of 5.45:1. Enough H2SO4 could be generated from the H2S emitted at this ratio to effect sufficient metal solubilisation and pathogen removal from primary sludge.</jats:p

On the development of the brown spider Loxosceles gaucho Gertsch (Araneae, Sicariidae): the nympho-imaginal period

Observations of the developmental biology of Loxosceles gaucho Gertsch, 1967, the brown spider of southeastern Brazil are scarce. The present study reports the method of individualized rearing of 18 populations of L. gaucho, kept in laboratory under varied diet conditions, and characterizes their nympho-imaginal period as well as factors related to their reproduction. Females built the first egg sac about 20 days after copulation and nymphs hatched 40 days after the laying date. Average offspring was 61.3 spiderlings and females usually built three to four successive egg sacs in a period of five to seven months. First nymphs initiated their predatory activity between the 5th and 8th days after hatching and the majority reached adulthood within six moults (range of five to eight) in approximately 15 to 17 months (male) and 15.5 to 18 months (female). The average sex ratio equaled 1.0:1.7 (male:female). The wide individual variability of this species intermoult intervals is herewith expressed by the "intermoult rate", which was fairly uniform for both intra and interpopulations and gives a relevant aspect for a general idea of the life cycles of spiders

Treatment of peripheral neuropathies.

There are three general approaches to treatment of peripheral neuropathy. First, an attempt should be made to reverse the pathophysiological process if its nature can be elucidated. Second, nerve metabolism can be stimulated and regeneration encouraged. Third, even if the neuropathy itself cannot be improved, symptomatic therapy can be employed. This review outlines the options available for each approach