When are total concentrations not total? Factors affecting geochemical analytical techniques for measuring element concentrations in soil

Inductively coupled plasma (ICP) following aqua regia digestion and X-ray fluorescence (XRF) are both geochemical techniques used to determine ‘total’ concentrations of elements in soil. The aim of this study is to compare these techniques, identify elements for which inconsistencies occur and investigate why they arise. A study area (∼14,000 km2) with a variety of total concentration controls and a large geochemical dataset (n = 7950) was selected. Principal component analysis determined underlying variance in a dataset composed of both geogenic and anthropogenic elements. Where inconsistencies between the techniques were identified, further numerical and spatial analysis was completed. The techniques are more consistent for elements of geogenic sources and lead, whereas other elements of anthropogenic sources show less consistency within rural samples. XRF is affected by sample matrix, while the form of element affects ICP concentrations. Depending on their use in environmental studies, different outcomes would be expected from the techniques employed, suggesting the choice of analytical technique for geochemical analyses may be more critical than realised.

Concentration effects of 1,2-dichlorobenzene on soil microbiology

The effect of increasing concentrations (65, 130, 325, 1,300, and 3,250 μg/g soil dry weight) of 1,2-dichlorobenzene (1,2-DCB) on the microbial biomass, metabolic potential, and diversity of culturable bacteria was investigated using soil microcosms. All doses caused a significant (p < 0.05) decrease in viable hyphal fungal length. Bacteria were more tolerant, only direct total counts in soils exposed to 3,250 μg/g were significantly (p < 0.05) lower than untreated controls, and estimates of culturable bacteria showed no response. Pseudomonads counts were stimulated by 1,2-DCB concentrations of up to 325 μg/g; above this level counts were similar to controls. Fatty acid methyl ester analysis of taxonomic bacterial composition reflected the differential response of specific genera to increasing 1,2-DCB concentrations, especially the tolerance of Bacillus to the highest concentrations. The shifts in community composition were reflected in estimates of metabolic potential assessed by carbon assimilation (Biolog) ability. Significantly fewer (p < 0.05) carbon sources were utilized by communities exposed to 1,2-DCB concentrations greater than 130 μg/g (<64 carbon sources utilized) than control soils (83); the ability to assimilate individual carbohydrates sources was especially compromised. The results of this study demonstrate that community diversity and metabolic potential can be used as effective bioindicators of pollution stress and concentration effects.

Meta-analysis of prostate cancer gene expression data identifies a novel discriminatory signature enriched for glycosylating enzymes

BACKGROUND: Tumorigenesis is characterised by changes in transcriptional control. Extensive transcript expression data have been acquired over the last decade and used to classify prostate cancers. Prostate cancer is, however, a heterogeneous multifocal cancer and this poses challenges in identifying robust transcript biomarkers.

METHODS: In this study, we have undertaken a meta-analysis of publicly available transcriptomic data spanning datasets and technologies from the last decade and encompassing laser capture microdissected and macrodissected sample sets.

RESULTS: We identified a 33 gene signature that can discriminate between benign tissue controls and localised prostate cancers irrespective of detection platform or dissection status. These genes were significantly overexpressed in localised prostate cancer versus benign tissue in at least three datasets within the Oncomine Compendium of Expression Array Data. In addition, they were also overexpressed in a recent exon-array dataset as well a prostate cancer RNA-seq dataset generated as part of the The Cancer Genomics Atlas (TCGA) initiative. Biologically, glycosylation was the single enriched process associated with this 33 gene signature, encompassing four glycosylating enzymes. We went on to evaluate the performance of this signature against three individual markers of prostate cancer, v-ets avian erythroblastosis virus E26 oncogene homolog (ERG) expression, prostate specific antigen (PSA) expression and androgen receptor (AR) expression in an additional independent dataset. Our signature had greater discriminatory power than these markers both for localised cancer and metastatic disease relative to benign tissue, or in the case of metastasis, also localised prostate cancer.

CONCLUSION: In conclusion, robust transcript biomarkers are present within datasets assembled over many years and cohorts and our study provides both examples and a strategy for refining and comparing datasets to obtain additional markers as more data are generated.

Experimental validation of a drive-by stiffness identification method for bridge monitoring

An experimental investigation is carried out to verify the feasibility of using an instrumented vehicle to detect and monitor bridge dynamic parameters. The low-cost method consists of the use of a moving vehicle fitted with accelerometers on its axles. In the laboratory experiment, the vehicle–bridge interaction model consists of a scaled two-axle vehicle model crossing a simply supported steel beam. The bridge model also includes a scaled road surface profile. The effects of varying the vehicle model configuration and speed are investigated. A finite element beam model is calibrated using the experimental results, and a novel algorithm for the identification of global bridge stiffness is validated. Using measured vehicle accelerations as input to the algorithm, the beam stiffness is identified with a reasonable degree of accuracy.

Experimental investigation of thermal inertia properties in hemp-lime concrete walls

Hemp-lime concrete is a sustainable alternative to standard building wall materials, with low associated embodied energy. It exhibits good hygric, acoustic and thermal properties, making it an exciting, sustainable building envelope material. When cast in temporary shuttering around a timber frame, it exhibits lower thermal conductivity than concrete, and consequently achieves low U-values in a primarily mono-material wall construction. Although cast relatively thick hemp-lime walls do not generally achieve the low U-values stipulated in building regulations. However assessment of its thermal performance through evaluation of its resistance to thermal transfer alone, underestimates its true thermal quality. The thermal inertia, or reluctance of the wall to change its temperature when exposed to changing environmental temperatures, also has a significant impact on the thermal quality of the wall, the thermal comfort of the interior space and energy consumption due to space heating. With a focus on energy reduction in buildings, regulations emphasise thermal resistance to heat transfer with only less focus on thermal inertia or storage benefits due to thermal mass. This paper investigates dynamic thermal responsiveness in hemp-lime concrete walls. It reports the influence of thermal conductivity, density and specific heat through analysis of steady state and transient heat transfer, in the walls. A novel hot-box design which isolates the conductive heat flow is used, and compared with tests in standard hot-boxes. Thermal diffusivity and effusivity are evaluated, using experimentally measured conductivity, based on analytical relationships. Experimental results evident that hemp-lime exhibits high thermal inertia. They show the thermal inertia characteristics compensate for any limitations in the thermal resistance of the construction material. When viewed together the thermal resistance and mass characteristics of hemp-lime are appropriate to maintain comfortable thermal indoor conditions and low energy operation.

The International Regulatory Regime on Capital Flows

Capital controls and exchange restrictions are used to restrict international capital flows during economic crises. This paper looks at the legal implications of these restrictions and explores the current international regulatory framework applicable to international capital movements and current payments. It shows how international capital flows suffer from the lack of a comprehensive and coherent regulatory framework that would harmonize the patchwork of
multilateral, regional, and bilateral treaties that currently regulate this issue. These treaties include the Articles of Agreement of the International Monetary Fund (IMF Articles), the General Agreement on Trade in Services (GATS), free-trade agreements, the European Union treaty, bilateral investment treaties, and the Organization for Economic Co-operation and Development (OECD) Code of Liberalization of Capital Movements (OECD Code of Capital Movement). Each
of these instruments regulate differently capital movements with little coordination with other areas of law. This situation sometimes leads to regulatory overlaps and conflict between different sources of law. Given the strong links between capital movements and trade in services, this paper pays particular attention to the rules of the GATS on capital flows and discusses the policy space available in the GATS for restricting capital flows in times of crisis.

Closed circuit rebreathing to achieve inert gas wash-in for multiple breath wash-out

Multiple breath wash-out (MBW) testing requires prior wash-in of inert tracer gas. Wash-in efficiency can be enhanced by a rebreathing tracer in a closed circuit. Previous attempts to deploy this did not account for the impact of CO2 accumulation on patients and were unsuccessful. We hypothesised that an effective rebreathe wash-in could be delivered and it would not alter wash-out parameters. Computer modelling was used to assess the impact of the rebreathe method on wash-in efficiency. Clinical testing of open and closed circuit wash-in–wash-out was performed in healthy controls and adult patients with cystic fibrosis (CF) using a circuit with an effective CO2 scrubber and a refined wash-in protocol. Wash-in efficiency was enhanced by rebreathing. There was no difference in mean lung clearance index between the two wash-in methods for controls (6.5 versus 6.4; p=0.2, n=12) or patients with CF (10.9 versus 10.8; p=0.2, n=19). Test time was reduced by rebreathe wash-in (156 versus 230 s for CF patients, p<0.001) and both methods were well tolerated. End wash-in CO2 was maintained below 2% in most cases. Rebreathe–wash-in is a promising development that, when correctly deployed, reduces wash-in time and facilitates portable MBW testing. For mild CF, wash-out outcomes are equivalent to an open circuit.

Sustainable non-automotive vehicles: The simulation challenges

Simulation is a well-established and effective approach to the development of fuel-efficient and low-emissions vehicles in both on-highway and off-highway applications.

The simulation of on-highway automotive vehicles is widely reported in literature, whereas research relating to non-automotive and off-highway vehicles is relatively sparse. This review paper focuses on the challenges of simulating such vehicles and discusses the differences in the approach to drive cycle testing and experimental validation of vehicle simulations. In particular, an inner-city diesel-electric hybrid bus and an ICE (Internal Combustion Engine) powered forklift truck will be used as case studies.

Computer prediction of fuel consumption and emissions of automotive vehicles on standardised drive cycles is well-established and commercial software packages such as AVL CRUISE have been specifically developed for this purpose. The vehicles considered in this review paper present new challenges from both the simulation and drive-cycle testing perspectives. For example, in the case of the forklift truck, the drive cycles involve reversing elements, variable mass, lifting operations, and do not specify a precise velocity-time profile. In particular, the difficulties associated with the prediction of productivity, i.e. the maximum rate of completing a series of defined operations, are discussed. In the case of the hybrid bus, the standardised drive cycles are unrepresentative of real-life use and alternative approaches are required in the development of efficient and low-emission vehicles.

Two simulation approaches are reviewed: the adaptation of a standard automotive vehicle simulation package, and the development of bespoke models using packages such as MATLAB/Simulink.

Nonsteroidal Anti-Inflammatory Drug Use is Not Associated With Reduced Risk of Barrett’s Esophagus

OBJECTIVES: Regular use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with a reduced risk of esophageal adenocarcinoma. Epidemiological studies examining the association between NSAID use and the risk of the precursor lesion, Barrett’s esophagus, have been inconclusive.

METHODS: We analyzed pooled individual-level participant data from six case-control studies of Barrett’s esophagus in the Barrett’s and Esophageal Adenocarcinoma Consortium (BEACON). We compared medication use from 1474 patients with Barrett’s esophagus separately with two control groups: 2256 population-based controls and 2018 gastroesophageal reflux disease (GERD) controls. Study-specific odds ratios (OR) and 95% confidence intervals (CI) were estimated using multivariable logistic regression models and were combined using a random effects meta-analytic model.

RESULTS: Regular (at least once weekly) use of any NSAIDs was not associated with the risk of Barrett’s esophagus (vs. population-based controls, adjusted OR = 1.00, 95% CI = 0.76–1.32; I2=61%; vs. GERD controls, adjusted OR = 0.99, 95% CI = 0.82–1.19; I2=19%). Similar null findings were observed among individuals who took aspirin or non-aspirin NSAIDs. We also found no association with highest levels of frequency (at least daily use) and duration (≥5 years) of NSAID use. There was evidence of moderate between-study heterogeneity; however, associations with NSAID use remained non-significant in “leave-one-out” sensitivity analyses.

CONCLUSIONS: Use of NSAIDs was not associated with the risk of Barrett’s esophagus. The previously reported inverse association between NSAID use and esophageal adenocarcinoma may be through reducing the risk of neoplastic progression in patients with Barrett’s esophagus.