Bio-availability of tungsten in the vicinity of an abandoned mine in the English Lake District and some potential health implications

This research addresses the occurrence, detection and possible fate of tungsten in the vicinity of an abandoned mine in the English Lake District. Aqua regia extraction and subsequent analysis of spoil and vegetation confirmed the presence of tungsten and other heavy metals. Spoil samples examined were last worked almost 100 years ago and the concentrations of copper, zinc, tungsten and arsenic detected demonstrate the environmental persistence of these metals in an area of relatively high rainfall. The bioaccumulation of tungsten by two species of plants is indicated and partitioning within different tissues of Calluna vulgaris is demonstrated. Mechanisms relating to mobility and speciation of the metals present were explored using sequential and single stage extraction systems. Tungsten appears to be relatively immobile when subjected to sequential extraction but increased bioavailability is indicated when single stage extraction using EDTA is employed.     

A comprehensive two-dimensional retention time alignment algorithm to enhance chemometric analysis of comprehensive two-dimensional separation data

A comprehensive two-dimensional (2D) retention time alignment algorithm was developed using a novel indexing scheme. The algorithm is termed comprehensive because it functions to correct the entire chromatogram in both dimensions and it preserves the separation information in both dimensions. Although the algorithm is demonstrated by correcting comprehensive two-dimensional gas chromatography (GC x GC) data, the algorithm is designed to correct shifting in all forms of 2D separations, such as LC x LC, LC x CE, CE x CE, and LC x GC. This 2D alignment algorithm was applied to three different data sets composed of replicate GC x GC separations of (1) three 22-component control mixtures, (2) three gasoline samples, and (3) three diesel samples. The three data sets were collected using slightly different temperature or pressure programs to engender significant retention time shifting in the raw data and then demonstrate subsequent corrections of that shifting upon comprehensive 2D alignment of the data sets. Thirty 12-min GC x GC separations from three 22-component control mixtures were used to evaluate the 2D alignment performance (10 runs/mixture). The average standard deviation of first column retention time improved 5-fold from 0.020 min (before alignment) to 0.004 min (after alignment). Concurrently, the average standard deviation of second column retention time improved 4-fold from 3.5 ms (before alignment) to 0.8 ms (after alignment). Alignment of the 30 control mixture chromatograms took 20 min. The quantitative integrity of the GC x GC data following 2D alignment was also investigated. The mean integrated signal was determined for all components in the three 22-component mixtures for all 30 replicates. The average percent difference in the integrated signal for each component before and after alignment was 2.6%. Singular value decomposition (SVD) was applied to the 22-component control mixture data before and after alignment to show the restoration of trilinearity to the data, since trilinearity benefits chemometric analysis. By applying comprehensive 2D retention time alignment to all three data sets (control mixtures, gasoline samples, and diesel samples), classification by principal component analysis (PCA) substantially improved, resulting in 100% accurate scores clustering.     

Going down the tube…dispense faster or die

For the textile printer the supply and mixing of the print paste is one of the more complex areas of production. Bob Coulton reviews these developments and suggests future trends will demand more integrated recipe systems and faster automatic dispensing.     

Uncertainty of air pollution cost estimates: to what extent does it matter?

How large is the social cost penalty if one makes the wrong choice because of uncertainties in the estimates of the costs and benefits of environmental policy measures? For discrete choices there is no general rule other than the recommendation to always carefully compare costs and benefits when introducing policies for environmental protection. For continuous choices (e.g., the ceiling for the total emissions of a pollutant by an entire sector or region), it is instructive to look at the cost penalty as a function of the error in the incremental damage cost estimate. Using abatement cost curves for NOx, SO2, dioxins, and CO2, this paper evaluates the cost penalty for errors in the following: national emission ceilings for NOx and SO2 in each of 12 countries of Europe, an emission ceiling for dioxins in the UK, and limits for the emission of CO2 in Europe. The cost penalty turns out to be remarkably insensitive to errors. An error by a factor of 3 due to uncertainties in the damage estimates for NOx and SO2 increases the total social cost by at most 20% and in most cases much less. For dioxins, the total social cost is increased by at most 10%. For CO2, several different possible cost curves are examined: for some the sensitivity to uncertainties is greater than for the other pollutants, but even here the penalty is less than 30% and in most cases much less if the true damage costs are twice as high as the ones estimated. The paper also quantifies the benefit of improving the accuracy of damage cost estimates by further research.     

Acute pancreatitis secondary to ifosfamide

Acute pancreatitis in cancer patients can be secondary to the malignant process itself. It is also a rare complication of antineoplastic agent administration. Ifosfamide is an effective drug in the treatment of several tumors and has known neurologic, renal, and hematologic toxicities. There is only one recent report in the literature of pancreatitis associated with ifosfamide. We report a case of a 65-year-old woman with small cell bronchogenic carcinoma without pancreatic metastases who developed acute pancreatitis after ifosfamide administration.     

Design-based studies: an action-based ‘form of knowledge’ for thinking,reasoning and operating

Some points of significance in the Royal College of Art report Design in general education have, to a certain extent, been insufficiently exploited by ‘doers and makers’. This paper re-acknowledges the contribution made by the identification of ‘modelling’ and ‘design awareness’ to the acceptability of action-based problem-solving. Simultaneously, the paper relates the RCA report to longer-term trends in thinking about traditional conceptions of knowledge divisions and boundaries. The RCA report is seen as an inevitable point on a continuum, but unfortunately it stopped short of suggesting action-based modes of knowing and thought as constituents of a ‘new’ discrete form of knowledge. This concept, outlined by Hirst, functions alongside the structures associated with verbal/mathematical and other language ‘tools’ used generally to organize aspects of reality in distinctive and characteristic ways and to generate new thought within the language mode and associated knowledge domain of ‘doing and making’.The paper goes on to propose a model which relates the imagery and structure of action-based knowledge with the principle theories on the thought-verbal language relationship and some other prominent observations on the nature of thought and language. As a follow-up to this it is necessary to outline the crucial importance of internalization of action-based experience so that both action-based imagery and structure are assimilated into the thinking, awareness and character of the individual.Finally the paper examines some of the implications this might have for the way design-based studies are to be viewed in the future.     

Exact optimal solution for facility layout: deciding which pairs of locations should be adjacent

This paper describes the development of a mathematical model for determining optimum block layout systems utilizing 0–1 integer programming as the optimization component. The objective function is to maximize a weighted sum of adjacent departments. The selected weight is a measure of the flow of material between departments. Developing a set of constraints, and changing the objective function to minimization of adjacency of departments with no interaction, it is shown that the procedure is capable of determining the optimal location in small size problems. To apply it to larger size problems, additional constraints are developed that help reduce the number of iterations for the integer program to converge to an optimal solution.     

Human alkyltransferase-transduced murine myeloid progenitors are enriched in vivo by BCNU treatment of transplanted mice

OBJECTIVES: To study the relation between the blood pressure and the neurocognitive function within the full adult age range in a large population sample. DESIGN: A cross-sectional study of 936 healthy adults who were recruited from a register of family practices, stratified for age (24-81 years), sex, and occupational level, who took part in a medical and neurocognitive test program. METHODS: The blood pressure status was studied in relation to five measures of cognitive ability, including verbal memory and speed of information processing. Other vascular risk factors were treated as control variables and included smoking, alcohol intake, body mass index, and body fat distribution. The blood pressure was measured five times using an automatic recording technique (with a Dinamap 8100 device). RESULTS: After adjustment for age, sex, and educational level in a hierarchical regression analysis, we found no unequivocal association between the mean systolic and diastolic blood pressures (or any other studied vascular risk factor) and cognitive test performance both for the whole group and for the subgroup of subjects who were not being administered antihypertensive medication and whose medical history did not include cardiovascular events. Stratified analysis within four age levels revealed no age-specific associations between the blood pressure and the cognitive function. Subjects whose blood pressure was within the hypertensive range performed worse than did matched controls at letter digit copying, but not according to other cognitive measures. CONCLUSIONS: With a population-based sample unselected for blood pressure status we found no linear relationship between the actual blood pressure level and various aspects of cognitive performance. Prospective studies are needed to investigate the possibility that the systemic blood pressure load over time is associated with a decline in specific cognitive abilities.