Some effects of prolonged starvation on the metabolism of the red and white myotomal muscles of the plaice Pleuronectes platessa

The effect of starvation on glycogen, lipid, water content and muscle proteins of red and white muscles in the plaice Pleuronectes platessa L. has been investigated. The two muscle systems behave differently in their response to food shortage, glycogen and protein depletion being more marked in the white muscle. Little change occurred in the constituents of the red muscle, except lipid. Starvation resulted in an increase in water content in the white, but not in the red muscle. The differential response of these two musole systems to starvation is discussed. It is suggested that the small amount of red muscle in the body is spared from the effects of starvation because it is needed for continuous activity during swimming at all speeds.     

Overview of proposed air emission standards and guidelines for municipal waste combustors

The EPA proposed regulations for municipal waste combustors (MWCs) on December 20, 1989. The regulations include (1) performance standards under Section 111(b) of the Clean Air Act (CAA) for new, modified, or reconstructed MWCs and (2) draft emission guidelines and compliance schedules for the states to use to develop control requirements from existing MWCs under Section 111(d). This paper will outline the proposed air emission standards and guidelines, as well as the basis for the prescribed emission limits. The schedule for the remainder of the regulations development will also be discussed.     

Cadmium in cereal grain and herbage from long-term experimental plots at Rothamsted, UK

Crop samples harvested and stored from three long-term agricultural experiments started in the 1840-1850s at Rothamsted Experimental Station (UK) have been analysed recently for Cd. Increased Cd burden in the soils of the experiments, which have had a range of treatments, originates mainly from atmospheric deposition. Soils treated with farmyard manure (FYM) or, in some cases, applications of phosphate fertilisers, have increased Cd levels. Herbage, wheat and barley grain from the three experiments were analysed by neutron activation analysis (NAA) and graphite furnace atomic absorption spectrometry (GFAAS). Samples were bulked for groups of years between 1860 and 1986, from variously treated plots in each experiment (control or 'nil' treatment, P-fertilised, FYM-amended, NPK-fertilised-limed and unlimed). There were marked differences in Cd concentrations between treatments. For example, uptake of Cd into herbage was greater where P fertiliser had been applied than not, and was greater from unlimed than limed soils. Offtake of Cd (mg ha(-1) year(-1)) was affected by large differences in yield and probably also by other factors. These include changes in botanical composition in the permanent grassland experiment; cultivar changes in the wheat and barley experiments; changes in soil organic matter and soil pH of some plots; changes in atmospheric deposition of Cd through time. All of these potentially confounding factors make the interpretation of results complicated. It is concluded, however, that, with one exception, there is little evidence of a long-term increase in crop Cd concentrations at Rothamsted.     

In vitro dissolution studies of uranium bearing material in simulated lung fluid

Inhaled uranium (U) bearing material will partially dissolve in the fluid lining of the lung, followed by a combination of retention, re-distribution, and excretion of the U. The rate of dissolution influences the retention time at the site of deposition, and the extent to which the material is available for re-distribution to other tissues. The consequential radiation dose is dependent upon the material distribution in the body and the exposure time to various tissues. The International Commission on Radiological Protection, ICRP 66 [International Commission on Radiological Protection (ICRP), 1994. Human Respiratory Tract Model for Radiological Protection. ICRP Publication 66] recommends the use of experimentally determined solubility coefficients in dose modelling. Material specific absorption parameters allow for better dose estimation than using ICRP default values for F (fast), M (moderate) and S (slow) classifications of U compounds. In vitro dissolution tests were carried out on U material collected from two U mines located in Australia. A static technique was designed in which particle samples were sandwiched between two 0.1-mum pore size membrane filters. The filter sandwich was exposed to a solvent (simulated lung fluid) for selected time intervals, at controlled test conditions for temperature and pH. The collected solution was analysed for U concentration using ICP-MS. The resulting dissolution curves were fitted with a double or triple exponential equation to determine the dissolution coefficients.     

Hydrothermal oxidation of waste lipids, protein, and starch from New Zealand meat- and vegetable-processing plants.

Disposal of organic waste materials from the meat- and vegetable-processing industries historically has been undertaken by dumping, drying followed by combustion, or biological oxidation. As a result of higher intensity processing rates and increasingly stringent legislation, these are no longer economical. Hydrothermal oxidation, also referred to as "wet" oxidation, has been used to lower the chemical and biological oxygen demand of waste samples from the above two industries. The starch-based wastes were readily oxidized without a catalyst. For the lipid and protein-based wastes, the use of copper calcium silicate and nitrate catalysts provided a significant reduction in oxygen demand at 230 degrees C.     

Variable Responses of Soybeans to Mixtures of Ozone and Sulfur Dioxide

Foliar injury and shoot fresh weight responses of soybeans (Glycine max L.) ‘Lee 68’ and ‘Dare’ exposed to mixtures of ozone (O₃) and sulfur dioxide (SO₂) were greater than additive (synergistic), less than additive (antagonistic), or additive. The result depended on the concentrations of O₃ and SO₂, the exposure duration, and the amount of injury caused by each gas singly. Synergism usually occurred when injury from O₃ or SO₂ singly was slight to moderate. Antagonism usually occurred when injury from either gas singly was severe. In many cases of antagonism, the injury and fresh weight effects of the mixture were less than those from SO₂ alone, suggesting that O₃ can sometimes protect soybeans from SO₂.