Selecting scenarios to assess exposure of surface waters to veterinary medicines in Europe

Registering a veterinary medicinal product (VMP) in the European Union requires assessing its potential to contaminate surface waters (SW) on a European scale. VMP are spread to land in manure or excreted during grazing and may enter SW through runoff, erosion, or leaching. Since the factors driving these processes vary largely across Europe, it is necessary to identify characteristic conditions, so-called scenarios, under which VMP enter SW. These scenarios may guide the parameterization of mechanistic fate models to predict environmental concentrations for environmental risk assessment. A number of such scenarios for pesticides and VMP have been developed rather pragmatically. Here, we describe how a geo-referenced European database of driving factors was used to divide the European environment into groups with similar conditions for SW contamination by VMP. Out of these groups, relevant exposure scenarios in Europe were selected by a simple scoring system. Comparing these to the existing scenarios showed that a number of situations are not well covered. The newly identified scenarios are primarily located in hilly areas of Central Europe and the Mediterranean, and in Eastern European plains with a continental climate. We recommend that they are included in the technical guidelines for higher-tier assessment of VMP.     

Temperature effects on tocopherol composition in soybeans with genetically improved oil quality

Tocopherol, a natural antioxidant, typically accounts for a small percentage of soybean (Glycine max L. Merr.) oil. Alleles that govern the expression of polyunsaturated fatty acids in soybean germplasm are influenced by temperature. However, little is known about the environmental influences on tocopherol expression. The objective of this study was to assess the influence of temperature on tocopherol composition in soybean germplasm that exhibit homozygous recessive and dominant alleles that govern the predominant ω-6 and ω-3 desaturases. The control cv. Dare and three low-18:3 genotypes (N78-2245, PI-123440, N85-2176) were grown under controlled-temperature environments during reproductive growth. Analysis of crude oil composition at various stages of seed development revealed a strong negative correlation between total tocopherol content and growth temperature. The relative strength of this correlation was greater in the germplasm that exhibited homozygous alleles governing the ω-6 desaturase than those governing the ω-3 desaturase. The decline in total tocopherol with reduced temperature was attributed predominantly to loss of γ-tocopherol. However, γ-tocopherol concentration also was directly related to 18:3 concentration in all genotypes. Thus, low-18:3 oils contained both a lower content and a lower concentration of γ-tocopherol. Although the biochemical basis for this observation is unknown, the antioxidant capacity of γ-tocopherol appeared to be directly associated with changes in oil quality that were mediated more by genetic than by environmental influences on 18:3 concentration. Another aspect of this work showed that low-18:3 soybean varieties should be expected to contain more α-tocopherol, especially when grown under normal commercial production environments. This condition should be regarded as another beneficial aspect of plant breeding approaches to the improvement of soybean oil quality.     

The EuroPhysiome, STEP and a roadmap for the virtual physiological human

Biomedical science and its allied disciplines are entering a new era in which computational methods and technologies are poised to play a prevalent role in supporting collaborative investigation of the human body. Within Europe, this has its focus in the virtual physiological human (VPH), which is an evolving entity that has emerged from the EuroPhysiome initiative and the strategy for the EuroPhysiome (STEP) consortium. The VPH is intended to be a solution to common infrastructure needs for physiome projects across the globe, providing a unifying architecture that facilitates integration and prediction, ultimately creating a framework capable of describing Homo sapiens in silico. The routine reliance of the biomedical industry, biomedical research and clinical practice on information technology (IT) highlights the importance of a tailor-made and robust IT infrastructure, but numerous challenges need to be addressed if the VPH is to become a mature technological reality. Appropriate investment will reap considerable rewards, since it is anticipated that the VPH will influence all sectors of society, with implications predominantly for improved healthcare, improved competitiveness in industry and greater understanding of (patho)physiological processes. This paper considers issues pertinent to the development of the VPH, highlighted by the work of the STEP consortium.     

Optimal automatic control of multistage production processes

Today's high-tech industries produce complicated products involving many processing steps. The usual approach of modeling and controlling each of these steps in isolation is re-evaluated. This work develops a data model of synchronized observations collected from several stages of a multistage manufacturing process, and proposes an across-stage automatic control scheme for adjusting nonstationary process drifts. The proposed controller applies dynamic programming tools to optimize multiple goals specified for individual process stages and possible mismatch between stages. Several examples and simulation studies demonstrate that the proposed method is a valuable tool for improving semiconductor manufacturing quality.     

ENVIRONMENTAL AND STRUCTURAL IMPLICATIONS FOR THE RE-USE OF TYRES IN FLUVIAL AND MARINE-CONSTRUCTION PROJECTS

There is increasing interest in reclaiming tyres for use in bank-side and coastal-protection structures. However, concern has been expressed about the potential for tyres to release pollutants into the environment and to retain their long-term structural stability. This paper describes laboratory leaching tests for heavy metals from new used tyres and tyres which have been exposed to an aquatic environment for thirteen years. The results show that the limiting factor to their use could be cadmium release. Tests found evidence of the loss of ultraviolet screening agents such as carbon black, suggesting that chemical breakdown of the tyre through leaching of vulcanising chemicals is more significant in the physical breakdown of the tyre, than the reverse. Three case studies of tyre flood-protection and river-control structures are presented, which examine the ability of tyres to retain structural integrity over long periods. Based on this evidence, guidance on design principles is offered. It is concluded that tyres can be used sustainably in a river or coastal environment, subject to careful consideration of local site conditions.     

Monitoring wastewater BOD using a non‐specific sensor array

An electronic nose incorporating a non‐specific sensor array of 12 conducting polymers was evaluated for its ability to monitor wastewater samples. Sewage samples collected from the inlet works, settlement tank and final effluent outlet over 5 months (January–May) were used to correlate the sensor responses of these samples with their corresponding 5‐day biochemical oxygen demand (BOD) values. Canonical correlation analysis (a linear reduction technique) showed that the relationship between the sensor responses and BOD over the 5 months was non‐linear. However, the separate analyses of subsets of these samples for shorter time periods showed that a linear relationship is apparent for time periods of 4 weeks or less, suggesting a correlation window occurs between the sensor responses and BOD. Preliminary neural network analysis supported these observations and using a three‐layer back‐propagation network showed that it is possible to predict BOD values from electronic nose analysis of a wastewater sample. The findings suggest that electronic nose technology could be used for the non‐invasive monitoring and/or control of a wastewater treatment process. © 1999 Society of Chemical Industry     

Oxidation of phytosterols in a test food system

The oxidative stability of phytosterols in canola, coconut, peanut, and soybean oils was examined under simulated frying conditions of 100, 150, and 180°C for 20 h. The degree of oxidative decomposition was assessed by the loss of phytosterols, accumulation of phytosterol oxides, and the change in fatty acid profiles. The phytosterol oxides produced in the oils were identified using mass spectroscopy. Oils with higher levels of polyunsaturated fatty acids showed greater amounts of sterol loss; however, the sterol loss was less complete than in the more saturated oils. A greater variety of sterol oxides was observed at the lower temperatures of 100 and 150°C compared to 180°C. This study demonstrates that under conditions similar to frying, there is a loss of phytosterols and polyunsaturated fatty acids. The accumulation of phytosterol oxides may be temperature-limited because of further break-down into products not measurable by typical gas chromatography-mass spectrometry techniques.     

Developmental regulation of sterol biosynthesis inCucurbita maxima L.

Twenty-two sterols were identified by capillary gas chromatography and capillary gas chromatography/mass spectroscopy inCucurbita maxima grown under green-house conditions. Both whole plants and individual tissues (leaves, stems, roots, cotyledons, flowers) were analyzed at weekly intervals during the 12-week development of the plant. In whole plants, sterol accumulation parallels plant growth except for a period in the mid-life cycle where there is a reduction in the amount of sterol accumulated on a total sterol/plant and mg sterol/g dry wt basis. This reduction in the amount of sterol is coincident with the visual onset of flowering. During development, the percent contribution of each class of sterol (Δ^5_, Δ^7_, Δ^0_-sterols) remains relatively constant. However, the percent contribution of an individual sterol species varies depending on the tissue examined and the developmental period selected for analysis. While the young plant (<2 weeks) possesses elevated levels of sterols with the Δ²⁵⁽²⁷⁾-double bond, the trend was toward a reduction in the amounts of these sterols with development. Leaves and stems accumulate large quantities of 24ζ-ethyl-5α-cholesta-7,22-dien-3β-ol (7,22-stigmastadienol) and 24ζ-ethyl-5α-cholest-7-en-3β-ol (7-stigmastenol), while roots accumulate only 7,22-stigmastadienol as their principal sterol. Male flowers and roots were found to contain elevated levels of Δ^5_-sterols.     

Learned aversions to proteins in rats on a dietary self-selection regimen.

101 Long-Evans and 38 Wistar rats in 4 experiments were allowed continuous access to protein and carbohydrate macronutrient sources during a sequence of cyclophosphamide (20 or 40 mg/kg, ip) injections. Significant aversions developed to the protein but not the carbohydrate source in the present experiments, in which the composition of both protein and carbohydrate diets was varied. Results suggest that Ss on a dietary self-selection regimen were more likely to develop conditioned aversions to the protein source than the carbohydrate source (Exps I, II, and III). In Exp IV, the generality of these findings was examined by determining whether aversions would selectively arise to proteins but not carbohydrates when these nutrients were conditioned in a single trial with a meal-feeding paradigm. Results show that proteins were again more salient targets for aversions than carbohydrates. Overall, findings suggest that the tendency to associate proteins with drug-induced illness more readily than carbohydrates is not limited to a self-selection regimen. The possible role of taste factors and/or postingestive effects as the basis for the differential conditioning of proteins and carbohydrates is discussed. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)