Risk communication as an operation meant to produce and share audiences

In this article, Luhmann's system theory is used as a theoretical framework for analysing the way risk communicators view their social functions. Narrated experiences from risk communicators in practice facilitate an understanding of risk communication as both an external irritation to society and part of the mass communication system. They also aid in clarifying how perceptions of audiences are reflected in the risk-communication strategies. The analysis is based on qualitative data collected from in-depth interviews conducted with 22 risk communicators (scientific professionals, spokespeople and journalists) in Israel. Thematic areas reflected in interviewees' reported strategies embody their perception of audiences. Those themes include: the reduction of complexities; coding and sorting of information; autopoiesis (realisation/non-realisation of the risk); rationality; inherent paradoxes; and schema formation. In sum, the findings suggest that risk communicators play a major role in defining, creating and producing audiences for the mass communication system

Gold nanoparticles electrodeposited on glassy carbon using cyclic voltammetry: Application to Hg(II) trace analysis

The electrochemical determination of Hg(II) at trace level using gold nanoparticles–modified glassy carbon (AuNPs–GC) electrodes is described. Starting from HAuCl4 in NaNO3, gold nanoparticles (AuNPs) were deposited onto Glassy Carbon (GC) electrodes using Cyclic Voltammetry (CV). Different deposits were obtained by varying the global charge consumed during the whole electroreduction step, depending on the number of cyclic potential scans (N). AuNPs were characterized as a function of the charge using both CV in H2SO4 and Field Emission Gun Scanning Electron Microscopy (FEG-SEM). The AuNPs–GC electrodes were then applied to determine low Hg(II) concentrations using Square Wave Anodic Stripping Voltammetry (SWASV). The AuNPs–GC electrodes provided significantly improved performances in Hg(II) determination compared to unmodified GC and bare Au electrodes. It was shown that the physico-chemical properties of the deposits are correlated to the performances of the AuNPs–GC electrode with respect to Hg(II) assay. The best results were obtained for four electrodeposition cyclic scans, where small-sized particles (36 ± 13 nm) with high density (73 particles μm-²) were obtained. Under these conditions, a linearity range from 0.64 to 4.00 nM and a limit of detection of 0.42 nM were obtained

DEGRADATION AND MOBILITY OF PETROLEUM HYDROCARBONS IN OILSANDS WASTE AT THE AURORA FORT HILLS DISPOSAL AREA

Surface mining in the Athabasca oil sands region of Northern Alberta, Canada, results in the disturbance of significant areas of boreal forest landscape. The Aurora Soil Capping Study is a reclamation research project that aims to find the optimal soil capping (cover) material and thickness to re-establish a boreal forest ecosystem above a lean oil sands (LOS) disposal area at Syncrude's Aurora North mine. The objectives of this laboratory and field-based study are to (1) characterize the in-situ hydrocarbon composition of the LOS material, (2) determine the effect of temperature on rates of gas flux and the biodegradation potential of petroleum hydrocarbons (PHC) as a result of microbial activity and (3) determine the potential for PHC to leach into the groundwater system. The results of the laboratory-study show that temperature has a significant effect on the rate of PHC degradation as indicated by the linear relationship observed between temperature and CO2 gas flux rates. The respiratory results from the laboratory-based study were consistent and relatively comparable with data from the field study, which indicates that the column study could be useful in estimating in situ PHC degradation

Diffraction techniques and vibrational spectroscopy opportunities to characterise bones

From a histological point of view, bones that allow body mobility and protection of internal organs consist not only of different organic and inorganic tissues but include vascular and nervous elements as well. Moreover, due to its ability to host different ions and cations, its mineral part represents an important reservoir, playing a key role in the metabolic activity of the organism. From a structural point of view, bones can be considered as a composite material displaying a hierarchical structure at different scales. At the nanometre scale, an organic part, i.e. collagen fibrils and an inorganic part, i.e. calcium phosphate nanocrystals are intimately mixed to assure particular mechanical properties

Molybdenum Induces the expression of a protein containing a new heterometallic Mo-Fe cluster in desulfoVibrio alaskensis

Biochemistry. 2009 Feb 10;48(5):873-82. doi: 10.1021/bi801773t.The characterization of a novel Mo-Fe protein (MorP) associated with a system that responds to Mo in Desulfovibrio alaskensis is reported. Biochemical characterization shows that MorP is a periplasmic homomultimer of high molecular weight (260 +/- 13 kDa) consisting of 16-18 monomers of 15321.1 +/- 0.5 Da. The UV/visible absorption spectrum of the as-isolated protein shows absorption peaks around 280, 320, and 570 nm with extinction coefficients of 18700, 12800, and 5000 M(-1) cm(-1), respectively. Metal content, EXAFS data and DFT calculations support the presence of a Mo-2S-[2Fe-2S]-2S-Mo cluster never reported before. Analysis of the available genomes from Desulfovibrio species shows that the MorP encoding gene is located downstream of a sensor and a regulator gene. This type of gene arrangement, called two component system, is used by the cell to regulate diverse physiological processes in response to changes in environmental conditions. Increase of both gene expression and protein production was observed when cells were cultured in the presence of 45 microM molybdenum. Involvement of this system in Mo tolerance of sulfate reducing bacteria is proposed

Mapping stem rust (Puccinia graminis f. sp. secalis) resistance in self-fertile winter rye populations

Rye stem rust caused by Puccinia graminis f. sp. secalis can be found in all European rye growing regions. When the summers are warm and dry, the disease can cause severe yield losses over large areas. To date only little research was done in Europe to trigger resistance breeding. To our knowledge, all varieties currently registered in Germany are susceptible. In this study, three biparental populations of inbred lines and one testcross population developed for mapping resistance were investigated. Over 2 years, 68–70 genotypes per population were tested, each in three locations. Combining the phenotypic data with genotyping results of a custom 10k Infinium iSelect single nucleotide polymorphism (SNP) array, we identified both quantitatively inherited adult plant resistance and monogenic all-stage resistance. A single resistance gene, tentatively named Pgs1, located at the distal end of chromosome 7R, could be identified in two independently developed populations. With high probability, it is closely linked to a nucleotide-binding leucine-rich repeat (NB-LRR) resistance gene homolog. A marker for a competitive allele-specific polymerase chain reaction (KASP) genotyping assay was designed that could explain 73 and 97% of the genetic variance in each of both populations, respectively. Additional investigation of naturally occurring rye leaf rust (caused by Puccinia recondita ROEBERGE) revealed a gene complex on chromosome 7R. The gene Pgs1 and further identified quantitative trait loci (QTL) have high potential to be used for breeding stem rust resistant rye

Using markers and field evaluation to identify the source of eyespot resistance gene Pch1 in the collection of wheat breeding lines

Pch1 gene translocated from Aegilops ventricosa provides effective resistance to eyespot in wheat. To track the Pch1 gene introgression, we investigated 372 genotypes obtained from various breeding programs using endopeptidase EpD1b marker, sequence-tagged-site (STS) marker XustSSR2001-7DL, and the score of infection index (K-index) evaluated after in vivo inoculation test. These genotypes were divided into three groups with 136, 124 and 112 genotypes for the field test lasting three years. In 2011, the mean K-index was 0.81, while 2012 and 2013 the mean K-indexes were 1.60 and 1.46, respectively. Both marker results indicated that 18 genotypes possessed Pch1 gene. Statistical analysis of the level of K-index showed that these 18 genotypes were resistant to eyespot, which verified the proper assignment of wheat genotypes with Pch1 gene based on the marker data. Thus, the endopeptidase and XustSSR2001-7DL are useful for identifying sources of eyespot resistance gene Pch1 in wheat breeding program