Anaerobic filter treatment of fishery wastewater

Anaerobic treatment of wastewater from a selected seafood processing plant was conducted at organic loading rates (OLR) ranging from 0.3 to 1.8 kg chemical oxygen demand (COD)/m³.day and hydraulic retention times (HRT) ranging from 36 to 6 days. COD reduction decreased with increasing OLR. More than 75% COD reduction could be maintained up to an OLR of about 1 kg COD/m³.day with an HRT of 11 days. An OLR of 1.3 kg COD/m³.day corresponding to an HRT of 6.6 days gave maximal biogas productivity of 1.5 m³/m³.day or 1.3 m³ biogas/kg COD with a 65% COD reduction. If the HRT was kept constant at 11 days, an OLR of 1.3 kg COD/m³.day achieved maximal biogas productivity (1.1 m³/m³.day) and yield (0.75 m³/kg COD) and a 60% COD reduction for treatment of tuna condensate.P. Prasertsan and S. Jung are with the Department of Agro-Industry, Faculty of Natural Resources, Prince of Songkla University, Hatyai 90110, Thailand. K.A. Buckle is with the Department of Food Science and Technology, University of New South Wales, Kensington, NSW 2033, Australia.     

Studies on polypeptide composition, hydrolytic activity and proton conduction of mitochondrial FoF1 H+ ATPase in regenerating rat liver

A study of the FoF1 ATPase complex of mitochondria isolated from regenerating rat liver following partial (70%) hepatectomy is presented. As we have previously reported, ATPase activity in submitochondrial particles prepared from regenerating rat liver 24 h following partial hepatectomy was depressed by 75% with respect to controls (submitochondrial particles from sham-operated animals). Polyacrylamide gel electrophoresis and immunodecoration using an antibody raised against isolated bovine heart F1 sector of the FoF1 ATPase indicated a substantial decrease in F1 content in the mitochondrial membrane from regenerating rat liver. Proton conduction by the FoF1 ATPase complex was studied by following the anaerobic relaxation of the transmembrane proton gradient (delta mu H+) generated by succinate-driven respiration. In control rat-liver submitochondrial particles containing the FoF1 moiety of the ATPase complex, anaerobic relaxation of delta mu H+ showed biphasic kinetics, whilst the same process in particles derived from regenerating rat liver exhibited monophasic kinetics and was significantly more rapid. Oligomycin and N,N-dicyclohexyl carbodiimide [(cHxN)2C] inhibited proton conductance by the F1-Fo ATPase complex in submitochondrial particles from both control and regenerating rat liver. Binding of [14C](cHxN)2C and immunodecoration using an antibody raised against bovine heart oligomycin-sensitivity-conferring protein (OSCP) indicated no difference in the content of either the (cHxN)2C binding protein or OSCP between control and regenerating rat-liver mitochondrial membranes. The results reported show that the structural and functional integrity of the Fo-F1 ATPase of rat liver is severely perturbed during regeneration.     

High-resolution genetic map around the spinal muscular atrophy (SMA) locus on chromosome 5.

Although autosomal recessive spinal muscular atrophy (SMA) has been mapped to chromosome 5q12-q13, there is for this region no genetic map based on highly informative markers. In this study we present the mapping of two previously reported microsatellite markers in 40 CEPH and 31 SMA pedigrees. We also describe the isolation of a new microsatellite marker at the D5S112 locus. The most likely order of markers (with recombination fractions given in parentheses) is 5cen-D5S6-(.02)-D5S125-(.04)-(JK53CA1/2,D5S11 2)-(.04)-D5S39-qter. The relative order of D5S6, D5S112, and D5S39 was confirmed by in situ hybridization. Multipoint linkage analysis in 31 SMA families indicates that the SMA locus lies in the 6-cM interval between D5S6 and JK53CA1/2, D5S112.     

Metabolic studies during normoglycaemic clamping of insulin-dependent diabetics using a glucose-controlled insulin infusion system.

Metabolic rhythms have been studied in six insulin-dependent diabetics during subcutaneous insulin therapy, and during control of blood glucose concentration by a glucose-controlled insulin infusion system (GCIIS). In none of the subjects was blood glucose concentration consistently within the normal range during subcutaneous insulin therapy. In contrast, blood glucose concentration was within the normal range after 3.5 h of insulin delivery by the glucose-controlled insulin infusion system and remained in the normal range for the following 8 h through lunch and dinner. Mean blood glucose concentration during this time ranged from 5.31 to 7.90 mM. Following normalisation of blood glucose concentration, blood lactate and pyruvate were similar with both the GCIIS and subcutaneous insulin therapy. Post-prandial lactate peaks were delayed with the GCIIS. Alanine levels were consistently higher during control with the GCIIS compared with subcutaneous therapy, while blood ketone body and plasma NEFA levels were lower, and the premeal peaks in the lipid metabolites were delayed. It is not possible to conclude that attainment of normoglycaemia with the present generation of glucose-controlled insulin infusion systems in insulin-dependent diabetics is accompanied by total normalisation of intermediary metabolism.     

MrGrid: A Portable Grid Based Molecular Replacement Pipeline

Background

The crystallographic determination of protein structures can be computationally demanding and for difficult cases can benefit from user-friendly interfaces to high-performance computing resources. Molecular replacement (MR) is a popular protein crystallographic technique that exploits the structural similarity between proteins that share some sequence similarity. But the need to trial permutations of search models, space group symmetries and other parameters makes MR time- and labour-intensive. However, MR calculations are embarrassingly parallel and thus ideally suited to distributed computing. In order to address this problem we have developed MrGrid, web-based software that allows multiple MR calculations to be executed across a grid of networked computers, allowing high-throughput MR.

Methodology/Principal Findings

MrGrid is a portable web based application written in Java/JSP and Ruby, and taking advantage of Apple Xgrid technology. Designed to interface with a user defined Xgrid resource the package manages the distribution of multiple MR runs to the available nodes on the Xgrid. We evaluated MrGrid using 10 different protein test cases on a network of 13 computers, and achieved an average speed up factor of 5.69.

Conclusions

MrGrid enables the user to retrieve and manage the results of tens to hundreds of MR calculations quickly and via a single web interface, as well as broadening the range of strategies that can be attempted. This high-throughput approach allows parameter sweeps to be performed in parallel, improving the chances of MR success.     

The effect of low doses of prostaglandin F2α infused into the aorta of unrestrained pregnant rats: Observations on induction of parturition and effect on plasma progesterone concentration

An intra-aortic infusion of 4.67 μg PGF2α/h for 11.5 h starting on Day 18 of gestation initiated parturition in rats within 40–41 h. There was no difference in latency in two groups in which the post-operative recovery period was approximately 5 h and 30 h respectively. Control animals infused with saline delivered live litters after 106 h.PGF2α-induced parturition was associated with a more rapid fall in the plasma progesterone concentration than in the saline infused control animals.Uterine activity was monitored by radiotelemetry. In Control saline infused animals changes occurring around the time of delivery were similar to those reported using intra-uterine balloons. The prostaglandin infused animals exhibited a similar sequence of changes. Maximal sensitivity of the uterus to stimulation by PGF2α was observed 25–35 h prior to delivery, and in the post-partum period.