Sand and gravel deposit evaluation using electrical resistivity tomography [extended abstract]

In this study, we assess the suitability of ERT for UK sand and gravel deposit assessment. To this end, we have reviewed the characteristics of deposits in terms of geological setting, thickness and heterogeneity to inform our survey design strategy. We have collated existing data on the electrical properties of UK sand and gravel, reviewed previous examples of ERT sand and gravel surveys, and undertaken detailed geophysical studies at seven potential or active sand and gravel extraction locations in East Anglia and the East Midlands

Preliminary evaluation of a constructed wetland for treating extremely alkaline (pH 12) steel slag drainage

High pH (> 12) leachates are an environmental problem associated with drainage from lime (CaO)rich industrial residues such as steel slags, lime spoil and coal combustion residues. Recent research has highlighted the potential for natural ('volunteer') wetlands to buffer extremely alkaline influent waters. This appears ascribable to high CO2 partial pressures in the wetland waters from microbial respiration, which accelerates precipitation of calcium carbonate (CaCO3), and the high specific surface area for mineral precipitation offered by macrophytes. The research presented here builds on this and provides preliminary evaluation of a constructed wetland built in March 2008 to buffer drainage from steel slag heaps in north-east England. The drainage water from the slag mounds is characterised by a mean pH of 11.9, high concentrations of Ca (up to 700 mg/L), total alkalinity (up to 800 mg/L as CaCO3) and are slightly brackish (Na = 300 mg/L; Cl = 400 mg/L) reflecting native groundwaters at this coastal setting. Documented calcite precipitation rates (mean of 5 g CaCO3/m(2)/day) from nearby volunteer sites receiving steel slag drainage were used to scale the constructed wetland planted with Phragmites australis; a species found to spontaneously grow in the vicinity of the discharge. Improved performance of the wetland during summer months may at least in part be due to biological activity which enhances rates of calcite precipitation and thus lowering of pH. Secondary Ca-rich precipitates also serve as a sink for some trace elements present at low concentrations in the slag leachate such as Ni and V. The implications for scaling and applying constructed wetlands for highly alkaline drainage are discussed

Pharmacokinetic study of a new testosterone-in-adhesive matrix patch applied every 2 days to hypogonadal men.

The present study assessed pharmacokinetic testosterone time profile and dose proportionality after application of a new matrix testosterone patch (30, 45, and 60 cm2 containing 0.5mg of testosterone per cm2). This open study was a single dose, three-period, crossover trial with a randomised treatment sequence in 24 hypogonadal men, consisting in a single 48-h application of two patches of 2x 30 cm2, 2x 45 cm2, 2x 60 cm2, separated by a 5-day wash-out. Testosterone concentrations were determined during patch application and after patch removal. Dose proportionality was assessed on baseline corrected, dose normalised parameters for C av,corr/D, C max,corr/D and AUC(0-48),corr/D. Testosterone concentrations rose during the first 9h following patch application, remained relatively sustained until 48 h and then decreased abruptly after patch removal, with a half-life of 1.3h. Testosterone levels were maintained above 3 ng/mL for 42-45 h with all patches. C av were 3.39, 4.03 and 4.58 ng/mL and Cmax were 4.33, 5.29 and 6.18 ng/mL according to the doses. AUC 0-48), C av and Cmax were dose dependent with mean ratios within the acceptance range (0.70-1.43). In conclusion, dose linearity was demonstrated between the different strengths of testosterone patches. Application resulted in dose proportional increases in serum T levels in hypogonadal men into the low to mid-normal range within the first hours and achieved steady state for 48 h. During this short term study with three consecutive patch applications, this patch was shown to be efficient, convenient and safe with excellent adhesiveness and skin tolerability, and with no cross-contamination to partner or to environment

Coordinate system validation for kinematics analysis of the carpal bones

info:eu-repo/semantics/publishe

Mutual Information Analysis: a comprehensive study

Contains fulltext : 84109.pdf (preprint version ) (Open Access