Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead

Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety 'Mode of Action' framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology.

Local and landscape effects on bee functional guilds in pigeon pea crops in Kenya

Pollinators face many challenges within agricultural systems due to landscape changes and intensification which can affect resource availability that can impact pollination services. This paper examines pigeon pea pollination and considers how landscape context and agricultural intensification in terms of pesticide use affects the abundance of bees characterized by species guilds on crops. The study was conducted on six paired farms across a gradient of habitat complexity based on the distance of each farm from adjacent semi-natural vegetation in Kibwezi Sub-county, Kenya. The study found that farms which do not use insecticides in farm management, but are in close proximity to natural habitat have greater bee guild abundance, but at further distances, overall abundance is reduced with or without insecticide use. At 1 km landscape radius, the complexity of habitats but not patch size had a positive impact on the abundance of cavity nesting bees and mason bees, which can be attributed to the interspersion of the small-holder farms with semi-natural habitats across the landscapes producing mosaics of heterogeneous habitats. The study revealed the strongest relationships between fruit set and bee abundance to be with the carpenter bee, social bee and solitary bee guilds, which are among the most abundant bees visiting pigeon pea flowers in this system. Our findings provide the foundation for conservation efforts by identifying which bee guilds pollinated pigeon peas. From this study, we suggest managing the floral and nesting resources that would best support the most abundant crop pollinators, and also reducing insecticide application to the crop.

Characterization of para-Nitrophenol-degrading bacterial communities in river water by using functional markers and stable isotope probing

Microbial degradation is a major determinant of the fate of pollutants in the environment. para-Nitrophenol (PNP) is an EPA listed priority pollutant with a wide environmental distribution, but little is known about the microorganisms that degrade it in the environment. We studied the diversity of active PNP-degrading bacterial populations in river water using a novel functional marker approach coupled with [13C6]PNP stable isotope probing (SIP). Culturing together with culture-independent terminal restriction fragment length polymorphism analysis of 16S rRNA gene amplicons identified Pseudomonas syringae to be the major driver of PNP degradation in river water microcosms. This was confirmed by SIP-pyrosequencing of amplified 16S rRNA. Similarly, functional gene analysis showed that degradation followed the Gram-negative bacterial pathway and involved pnpA from Pseudomonas spp. However, analysis of maleylacetate reductase (encoded by mar), an enzyme common to late stages of both Gram-negative and Gram-positive bacterial PNP degradation pathways, identified a diverse assemblage of bacteria associated with PNP degradation, suggesting that mar has limited use as a specific marker of PNP biodegradation. Both the pnpA and mar genes were detected in a PNP-degrading isolate, P. syringae AKHD2, which was isolated from river water. Our results suggest that PNP-degrading cultures of Pseudomonas spp. are representative of environmental PNP-degrading populations.

Young Children's Ability to Engage in Cognitive Therapy Tasks: Associations With Age and Educational Experience

Abstract. In two linked studies we examined children’s performance on tasks required for participation in cognitive therapy. In Study 1 we piloted some new tasks with children aged 5 to 11 years. In study 2 the effects of IQ, age and educational experience were examined in children aged 5 to 7 years. In study 1, 14 children aged 5 to 11 completed three tasks related to cognitive therapy; generating post-event attributions, naming emotions, and linking thoughts and feelings. Study 2 used a between-subjects design in which 72 children aged 5, 6, or 7 years from two primary schools completed the three tasks and the Block Design and Vocabulary sub-tests from the WISC III or WPPSI-R. Children were tested individually during the school day. All measures were administered on the same occasion. In study 2 administration order of the cognitive therapy task and the WISC III/WPPSI-R were randomized. The majority of children demonstrated some ability on each of the three tasks. In study 2, performance was associated with school and with IQ but not with age. There were no gender differences. Children attending a school with an integrated thinking skills programme and those with a higher 1Q were more successful on the cognitive therapy tasks. These results suggest that many young children could engage in cognitive therapy given age-appropriate materials. The effects of training in relevant meta-cognitive skills on children’s ability to use concepts in CBT may warrant further research. Keywords: Cognitive behaviour therapy, young children, cognitive development

Effect of air-drying pre-treatment on the characterization of forest soil carbon pools

Archived soils could represent a valuable resource for the spatio-temporal inventory of soil carbon stability. However, archived soils are usually air-dried before storage and the impact of a drying pretreatment on physically and chemically-defined C fractions has not yet been fully assessed. Through the comparison of field-moist and corresponding air-dried (at 25oC for 2 weeks) forest soil samples, we examined the effect of air-drying on: a) the quantity and the quality of cold- (CWEC) and hot-water (HWEC) extractable C and b) the concentration of C in physically isolated fractions (free- and intra-aggregate light and organo-mineral). Soil samples were collected from the organic (O) and mineral (A and B) horizons of three different forest soils from southeastern England: (i) Cambisol under Pine (Pinus nigra); (ii) Cambisol under Beech (Fagus sylvatica) and (iii) Gleysol under oak (Quercus robur). CWEC concentrations for dry samples were up to 2 times greater than for corresponding field moist samples and had significantly (p < 0.001) higher phenolic content. However, the effect of drying pretreatment on HWEC, its phenolic content was not significant (p > 0.05) for most samples. Dried soils had significantly (p < 0.001) higher concentrations of free light-C while having lower concentrations of intra-aggregate-C when compared to moist samples (p < 0.001). However, fine silt and clay fractions were not significantly affected by the drying pretreatment (p=0.789). Therefore, based on the results obtained from gleysol and cambisol forest soils studied here, C contents in hot-water extractions and fine particle size physical fractions (< 25µm) seem to be robust measurements for evaluating C fractions in dried stored forest soils. Further soil types should be tested to evaluate the wider generality of these findings.

The role of Planning Aid England in supporting communities’ engagement in planning

In considering the position of community engagement within planning in a time of neo-liberalism and a context of ‘neo-communitarian localism’ (cf. Jessop, 2002; DeFilippis, 2004), this paper reviews the role and relevance of Planning Aid in terms of its performance and aspirations in guiding and transforming planning practice (Friedmann, 1973; 1987; 2011) since its inception in 1973. In doing this we reflect on the critiques of Planning Aid performance provided by Allmendinger (2004) and bring the account up-to-date following on from past considerations (e.g. Bidwell and Edgar, 1982; Thomas, 1992; Brownill and Carpenter, 2007a,b; Carpenter and Brownill, 2008) and prompted by the 35 years since the University of Reading produced the first published work reviewing Planning Aid (Curtis and Edwards, 1980). Our paper is timely given renewed attacks on planning, the implementation of a form of localism and reductions in funding for planning in a time of austerity. Our view is that the need for forms of ‘neo-advocacy’ planning and community development are perhaps even more necessary now, given the continuing under-representation of lower income groups, minority groups and to allow for the expression of alternative planning futures. Thus further consideration of how to ensure that Planning Aid functions are sustained and understood requires the attention of policymakers and the planning profession more widely.

Exploring smart grid possibilities: a complex systems modelling approach

Smart grid research has tended to be compartmentalised, with notable contributions from economics, electrical engineering and science and technology studies. However, there is an acknowledged and growing need for an integrated systems approach to the evaluation of smart grid initiatives. The capacity to simulate and explore smart grid possibilities on various scales is key to such an integrated approach but existing models – even if multidisciplinary – tend to have a limited focus. This paper describes an innovative and flexible framework that has been developed to facilitate the simulation of various smart grid scenarios and the interconnected social, technical and economic networks from a complex systems perspective. The architecture is described and related to realised examples of its use, both to model the electricity system as it is today and to model futures that have been envisioned in the literature. Potential future applications of the framework are explored, along with its utility as an analytic and decision support tool for smart grid stakeholders.

Novel European free-living, non-diazotrophic Bradyrhizobium isolates from contrasting soils that lack nodulation and nitrogen fixation genes - a genome comparison

The slow-growing genus Bradyrhizobium is biologically important in soils, with different representatives found to perform a range of biochemical functions including photosynthesis, induction of root nodules and symbiotic nitrogen fixation and denitrification. Consequently, the role of the genus in soil ecology and biogeochemical transformations is of agricultural and environmental significance. Some isolates of Bradyrhizobium have been shown to be non-symbiotic and do not possess the ability to form nodules. Here we present the genome and gene annotations of two such free-living Bradyrhizobium isolates, named G22 and BF49, from soils with differing long-term management regimes (grassland and bare fallow respectively) in addition to carbon metabolism analysis. These Bradyrhizobium isolates are the first to be isolated and sequenced from European soil and are the first free-living Bradyrhizobium isolates, lacking both nodulation and nitrogen fixation genes, to have their genomes sequenced and assembled from cultured samples. The G22 and BF49 genomes are distinctly different with respect to size and number of genes; the grassland isolate also contains a plasmid. There are also a number of functional differences between these isolates and other published genomes, suggesting that this ubiquitous genus is extremely heterogeneous and has roles within the community not including symbiotic nitrogen fixation.

Brumadoite, a new copper tellurate hydrate, from Brumado, Bahia, Brazil

Brumadoite, ideally Cu(2)Te(6+)O(4)(OH)(4)center dot 5H(2)O, is a new mineral from Pedra Preta mine, Serra das Eguas, Brumado, Bahia, Brazil. It occurs as microcrystalline aggregates both on and, rarely, pseudomorphous after coarse-grained magnesite, associated with mottramite and quartz. Crystals are platy, subhedral, 1-2 mu m in size. Brumadoite is blue (near RHS 114B), has a pale blue streak and a vitreous lustre. It is transparent to translucent and does not fluoresce. The empirical formula is (Cu(2.90)Pb(0.04)Ca(0.01))(Sigma 2.95) (Te(0.93)(6+)Si(0.05))(Sigma 0.98)O(3.92)(OH)(3.84)center dot 5.24H(2)O. Infrared spectra clearly show both (OH) and H(2)O. Microchemical spot tests using a KI Solution show that brumadoite has tellurium in the 6(+) state. The mineral is monoclinic, P2(1)/m or P2(1). Unit-cell parameters refined from X-ray powder data are a 8.629(2) angstrom, b 5.805(2) angstrom, c 7.654(2) angstrom, beta 103.17(2)degrees, V 373.3(2) angstrom(3), Z = 2. The eight strongest X-ray powder-diffraction lines [d in angstrom, (l),(hkl)] are: 8.432,(100),(100); 3.162,(66),((2) over bar 02); 2.385,(27),(220); 2.291,((1) over bar 12),(22); 1.916,(11),(312); 1.666,(14),((4) over bar 22,114); 1.452,(10), (323, 040); 1.450,(10),(422,403). The name is for the type locality, Brumado, Bahia, Brazil. The new mineral species has been approved by the CNMNC (IMA 2008-028).

Alex E. Davis, Graduate of the New York Trade School

Alexander Davis, Jr., a graduate of the Carpentry program of the New York Trade School in 1955 is shown working. Original caption reads, "Carpenter Contractor, Alex E. Davis Builder, Easton, Pa. Alexander Davis, Jr. - Carpentry 1955. The remodeling of old and building of new houses etc., offers many opportunities for success. Mr. Davis is shown hanging a new door on a building." Black and white photograph with caption glued to reverse.