Comparative study of the temporal evolution of atmospheric lead deposition in Scotland and eastern Canada using blanket peat bogs

The temporal evolution of atmospheric lead deposition and its possible sources were assessed in eastern Canada and in western Scotland, using blanket peat bogs as geochemical archives. Short cores were taken from two remote sites located close to the sea. Significant lead enrichments in the upper layers at both sites reflect the increasing emission of lead into the atmosphere due to anthropogenic activities during the last century. At the Scottish site, a region under aeolian influence from Europe, anthropogenic derived lead could be recognized by the distinctive unradiogenic composition (206Pb/207Pb ratios down to approximately 1.115), being clearly different from the pre-industrial values (206Pb/207Pb approximately 1.166). In contrast, the lead pollution in eastern Canada (influenced by North American sources) is identified by a more radiogenic lead isotope composition (206Pb/207Pb ratios up to approximately 1.199) compared to preindustrial values (206Pb/207Pb approximately 1.161). Emission inventories and isotope characteristics suggest that industrial (coal burning, mining) and traffic (leaded gasoline) outputs are the most likely sources during the first and the second half of the 20th century, respectively, in both, western Scotland and eastern Canada alike. The Scottish record is in line with previous studies of past atmospheric lead deposition. However, the Canadian deposit suggests that the wind derived, pre-industrial lead, is less radiogenic as previously implied using sediment archives. These results are thus the first to report pre-industrial lead isotope ratios and concentrations of atmospheric derived aerosols in North America.     

Modification of ASTM E 2187 for Measuring the Ignition Propensity of Conventional Cigarettes

Current existing and proposed US flammability standards for soft furnishings such as mattresses and upholstered furniture specify a ??standard?? cigarette as the ignition source in smoldering resistance performance tests. With the increasing prevalence of reduced ignition propensity cigarettes in the marketplace, the conventional cigarette that has been most widely used in smolder resistance testing is no longer in production. To support manufacturers and testing organizations in product design and testing, and to assist regulators in the compliance evaluation process, a continuing supply of standard conventional cigarettes is required. A key first step in establishing such a supply is the development of a measurement method for quantifying the ignition propensity of a standard cigarette similar to the one currently used for testing soft furnishings. This article describes such a measurement method. It also reports performance data for the conventional test cigarette and other contemporary cigarettes.     

Fusing Loop Detector and Probe Vehicle Data to Estimate Travel Time Statistics on Signalized Urban Networks

Abstract: This article presents a methodology that integrates cumulative plots with probe vehicle data for estimation of travel time statistics (average, quartile) on urban networks. The integration reduces relative deviation among the cumulative plots so that the classical analytical procedure of defining the area between the plots as the total travel time can be applied. For quartile estimation, a slicing technique is proposed. The methodology is validated with real data from Lucerne, Switzerland and it is concluded that the travel time estimates from the proposed methodology are statistically equivalent to the observed values.     

Establishing the link between market orientation and agricultural commercialization: Empirical evidence from Northern Ghana

This paper established a positive relationship between market orientation and intensity of commercialization among rural farm households in northern Ghana. The IV Tobit regression estimate suggests that intensity of maize commercialization is significantly determined by education, agro-ecology, household size, total livestock units, farm size, access to formal markets and market orientation. In addition, a highly and unbiased significant positive effect is observed between market orientation and intensity of maize commercialization after controlling for endogeneity in market orientation. Intensity of maize commercialization increased by 0.86% for a 0.1 unit increase in the market orientation index. The empirical implications of the results are discussed.     

The decontaminative effects of acidic electrolyzed water for Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes on green onions and tomatoes with differing organic demands

Acidic electrolyzed water (AC-EW) has strong bactericidal activity against foodborne pathogens on fresh vegetables. However, the efficacy of AC-EW is influenced by soil or other organic materials present. This study examined the bactericidal activity of AC-EW in the presence of organic matter, in the form of bovine serum against foodborne pathogens on the surfaces of green onions and tomatoes. Green onions and tomatoes were inoculated with a culture cocktail of Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes. Treatment of these organisms with AC-EW containing bovine serum concentrations of 5, 10, 15, and 20 ml/l was performed for 15 s, 30 s, 1 min, 3 min and 5 min. The total residual chlorine concentrations of AC-EW decreased proportional to the addition of serum. The bactericidal activity of AC-EW also decreased with increasing bovine serum concentration, whereas unamended AC-EW treatment reduced levels of cells to below the detection limit (0.7 logCFU/g) within 3 min.     

Effect of Infusion Method and Parameters on Solid Gain in Blueberries

In order to obtain optimal processing conditions for producing infused blueberries with high solid gain, we investigated the infusion characteristics of blueberries under various processing parameters in sugar solutions with 1:1 ratio of solution and berries. Static batch constant concentration infusion and dynamic batch infusion (DBI) were tested as the alternative operations for the traditional static batch infusion. The studied parameters were solution temperature (25 to 70 °C), concentration (20 to 70°Brix), and types of osmotic agent (fructose, dextrose, polydextrose, sucrose, maltodextrin, and corn syrup). The results showed that high solid gain can be achieved by maintaining high and constant concentration of infusion solution at high temperature with dynamic infusion. For DBI, high temperature and high solution concentration resulted in fast and high solid gain. The rate of water loss increased with an increase in solution temperature and concentration. To obtain high quality sugar-infused products with high product yield, a DBI process of 50 °C and 50°Brix sugar infusion is recommended, which could have solid gain of 1.65 g/g after a 5-h infusion. Polydextrose showed higher solid gain than sucrose when infusion time was longer than 180 min, although it had lower solid gain in short-term infusion.     

Chromatographic alignment of ESI-LC-MS proteomics data sets by ordered bijective interpolated warping

Mass spectrometry proteomics typically relies upon analyzing outcomes of single analyses; however, comparing raw data across multiple experiments should enhance both peptide/protein identification and quantitation. In the absence of convincing tandem MS identifications, comparing peptide quantities between experiments (or fractions) requires the chromatographic alignment of MS signals. An extension of dynamic time warping (DTW), termed ordered bijective interpolated warping (OBI-Warp), is presented and used to align a variety of electrospray ionization liquid chromatography mass spectrometry (ESI-LC-MS) proteomics data sets. An algorithm to produce a bijective (one-to-one) function from DTW output is coupled with piecewise cubic hermite interpolation to produce a smooth warping function. Data sets were chosen to represent a broad selection of ESI-LC-MS alignment cases. High confidence, overlapping tandem mass spectra are used as standards to optimize and compare alignment parameters. We determine that Pearson's correlation coefficient as a measure of spectra similarity outperforms covariance, dot product, and Euclidean distance in its ability to produce correct alignments with optimal and suboptimal alignment parameters. We demonstrate the importance of penalizing gaps for best alignments. Using optimized parameters, we show that OBI-Warp produces alignments consistent with time standards across these data sets. The source and executables are released under MIT style license at http://obi-warp.sourceforge.net/.     

Millimeter-wave antireflection coating for cryogenic silicon lenses

We have developed and tested an antireflection (AR) coating method for silicon lenses used at cryogenic temperatures and millimeter wavelengths. Our particular application is a measurement of the cosmic microwave background. The coating consists of machined pieces of Cirlex glued to the silicon. The measured reflection from an AR-coated flat piece is less than 1.5% at the design wavelength. The coating has been applied to flats and lenses and has survived multiple thermal cycles from 300 to 4 K. We present the manufacturing method, the material properties, the tests performed, and estimates of the loss that can be achieved in practical lenses.     

Chemical loading into surface water along a hydrological, biogeochemical, and land use gradient: a holistic watershed approach

Identifying the sources and impacts of organic and inorganic contaminants at the watershed scale is a complex challenge because of the multitude of processes occurring in time and space. Investigation of geochemical transformations requires a systematic evaluation of hydrologic, landscape, and anthropogenic factors. The 1160 km2 Boulder Creek Watershed in the Colorado Front Range encompasses a gradient of geology, ecotypes, climate, and urbanization. Streamflow originates primarily as snowmelt and shows substantial annual variation. Water samples were collected along a 70-km transect during spring-runoff and base-flow conditions, and analyzed for major elements, trace elements, bulk organics, organic wastewater contaminants (OWCs), and pesticides. Major-element and trace-element concentrations were low in the headwaters, increased through the urban corridor, and had a step increase downstream from the first major wastewater treatment plant (WWTP). Boron, gadolinium, and lithium were useful inorganic tracers of anthropogenic inputs. Effluent from the WWTP accounted for as much as 75% of the flow in Boulder Creek and was the largest chemical input. Under both hydrological conditions, OWCs and pesticides were detected in Boulder Creek downstream from the WWTP outfall as well as in the headwater region, and loads of anthropogenic-derived contaminants increased as basin population density increased. This report documents a suite of potential endocrine-disrupting chemicals in a reach of stream with native fish populations showing indication of endocrine disruption.