Toxicant distributions and impact models in environmental risk analysis of waste sites

Myrkyllisten aineiden jakaumat ja vaikutusmallit jätealueiden ympäristöriskien analyysissä.

Unique Utilization of a Phosphoprotein Phosphatase Fold by a Mammalian Phosphodiesterase Associated with WAGR Syndrome

Metallophosphoesterase-domain-containing protein 2 (MPPED2) is a highly evolutionarily conserved protein with orthologs found from worms to humans. The human MPPED2 gene is found in a region of chromosome 11 that is deleted in patients with WAGR (Wilms tumor, aniridia, genitourinary anomalies, and mental retardation) syndrome, and MPPED2 may function as a tumor suppressor. However, the precise cellular roles of MPPED2 are unknown, and its low phosphodiesterase activity suggests that substrate hydrolysis may not be its prime function. We present here the structures of MPPED2 and two mutants, which show that the poor activity of MPPED2 is not only a consequence of the substitution of an active-site histidine residue by glycine but also due to binding of AMP or GMP to the active site. This feature, enhanced by structural elements of the protein, allows MPPED2 to utilize the conserved phosphoprotein-phosphatase-like fold in a unique manner, ensuring that its enzymatic activity can be combined with a possible role as a scaffolding or adaptor protein. (C) 2011 Elsevier Ltd. All rights reserved.

Is land really a constraint for the utilization of solar energy in India?

This article compares the land use in solar energy technologies with conventional energy sources. This has been done by introducing two parameters called land transformation and land occupation. It has been shown that the land area transformed by solar energy power generation is small compared to hydroelectric power generation, and is comparable with coal and nuclear energy power generation when life-cycle transformations are considered. We estimate that 0.97% of total land area or 3.1% of the total uncultivable land area of India would be required to generate 3400 TWh/yr from solar energy power systems in conjunction with other renewable energy sources.

Tracking the evolution of waste recycling research using overlay maps of science

Tracking the evolution of research in waste recycling science (WRS) can be valuable for environmental agencies, as well as for recycling businesses. Maps of science are visual, easily readable representations of the cognitive structure of a branch of science, a particular area of research or the global spectrum of scientific production. They are generally built upon evidence collected from reliable sources of information, such as patent and scientific publication databases. This study uses the methodology developed by Rafols et al. (2010) to make a “double overlay map” of WRS upon a basemap reflecting the cognitive structure of all journal-published science, for the years 2005 and 2010. The analysis has taken into account the cognitive areas where WRS articles are published and the areas from where it takes its intellectual nourishing, paying special attention to the growing trends of the key areas. Interpretation of results lead to the conclusion that extraction of energy from waste will probably be an important research topic in the future, along with developments in general chemistry and chemical engineering oriented to the recovery of valuable materials from waste. Agricultural and material sciences, together with the combined economics, politics and geography field, are areas with which WRS shows a relevant and ever increasing cognitive relationship.

Utilization of freshwater fish species in Nigeria

The paper examines the pattern of utilization of freshwater fish species in Nigeria. It was observed that although fishermen have a preference for fresh fish sales only 30% of fresh fish captured actually get to the consumers. The rest are preserved by smoke curing (60-65%), salting and sundrying (less than 5%), deep frying and fermentation (about 1%). Constraints to fish utilization were identified which include poor infrastructure, losses of fish and fish products as a result of traditional post harvest technology and socio economic factors. The need for the development of appropriate research to solve the problems of traditional post harvest technology was emphasised

Utilization of agro-industrial wastes as fish feedstuffs in Nigeria

Fish feeding accounts for a substantial amount in the variable expenditure of a fish farming enterprises. There is a need to examine closely the potentials and advantages of locally available agro-industrial by-products, as possible substitutes for the conventional feedstuffs which are dwindling in supply, and escalating in their cost. A wide range of by products from plant, animal and industrial processes have been studied and posses nutrient composition which can be exploited as dietary ingredients for warm water species as the Tilapia and Clarias sp. Such useful by-products include poultry feathers, rice bran, soybean hulls and cocoa husks which are discarded as wastes. However, some processing treatments might be required to alleviate the toxic effects of possible anti-nutritional factors in the by-products, for the achievement of optimum benefit

Utilization of non-piscine pituitary extract in the breeding of Clarias gariepinus

The use of synthetic and non-synthetic hormones have been reported in different regions with the recommendation of different doses. The adaptability of these findings have however not been very successful due to the high cost of building and maintaining hatchery, high cost of synthetic hormone (when available) and high level manpower required. It is obvious that adaptive research in the past ten years in developing countries like Nigeria have been geared towards utilization of resources that are equally effective but cheap and ready to come by. This paper reports the utilization of the pituitary extract of bull frog (Rana adspersa) and the toad (Bufo regularis) in the induced breeding of the African catfish, Clarias gariepinus. The extraction and dosage are discussed alongside the preliminary rearing of fries in outdoor hatchery tanks. Human chorionic gonadotrophin (HCG) and Clarias pituitary extracts were used as control

Digestibility and nutrient utilization of soybean milk concentrate based diets in Oreochromis niloticus

The digestibility and utilisation of two fresh soybean milk concentrate based diets, two stale soybean milk concentrate based diets and two Fishman based diets serving as control, at optimal (30%) and suboptimal (20%) protein levels were evaluated in Oreochromis niloticus. The diets were as follows: Diet I (control) - fishmeal based diet at 30% crude protein, Diet II (control) Fishman based diet at 20% crude protein, Diet III - fresh soybean milk concentrate based diet at 30% crude protein, Diet IV - fresh soybean milk concentrate based diet at 20%, Diet V - stale soybean milk concentrate based diet at 30% crude protein, Diet VI-stale soybean milk concentrate based diet at 20%. Dry matter digestibility differed not significantly with variation in diets (P:0.05). A significant variation was recorded in the protein, lipid and ash digestibility. Proteins were more digestible at optimum than suboptimum level. Ash digestibility was lowest of all the nutrients. Variations in the utilisation of the diets in terms of weight gain, specific growth rate, food conversion ration, protein efficiency ration and apparent net protein utilization were insignificant (P: 0.05). All diets compared favourably with the standard control diet Diet I. This findings suggest the suitability of stale soybean milk concentrate utilisation as protein supplements in the diets of late fry Oreochromis niloticus

Storage potential and utilization of tilapia mince

Production of mince from Tilapia using a combination of physical and chemical methods was found to improve the storage life of the mince in the deep freezer. Though the chemical composition of the mince was slightly affected, the mince was microbiologically stable throughout the five weeks frozen storage. Fish cakes prepared traditionally from tilapia minces were more acceptable than oven dried cakes. Production of fish cakes form tilapia will improve utilization of this species in areas where small size tilapia are regarded as fish of low economic value

An investigation of the effect of replacing fish meal with soyabean meal, groundnut cake and blood meal at varied proportion on growth and food utilization of the Clarias anguillaris fingerlings fed in outdoor hapas

Fingerlings of Clarias anguillaris obtained from a homogenous source through induce breeding and each with a mean weight of 2.8g were stocked in ten hapas each measuring 1.0x1.0m in outdoor concrete tank and were fed for eight (8) weeks. Results shows that the best growth rate was recorded among fingerlings fed fish meal as the only protein source (TD5) while DT2 containing soya bean, groundnut cake (40%), blood meal as the protein sources came next. The growth rate of fingerlings fed DT2 (40 % groundnut cake, 10% soyabean meal and 10% blood meal) was higher than those fed DT4 containing 10% fish meal but lower than those fed DT5 which has fish meal as its sole source of protein (53.0%). Analysis of various growth parameters like SGR, FCR and PER. shows that DT5 was the overall best diet but there was no significant statistical difference in weight gained by fish fed the five diets (P <0.05)