Using Residential History and Groundwater Modeling to Examine Drinking Water Exposure and Breast Cancer

BACKGROUND. Spatial analyses of case-control data have suggested a possible link between breast cancer and groundwater plumes in upper Cape Cod, Massachusetts. OBJECTIVE. We integrated residential histories, public water distribution systems, and groundwater modeling within geographic information systems (GIS) to examine the association between exposure to drinking water that has been contaminated by wastewater effluent and breast cancer. METHODS. Exposure was assessed from 1947 to 1993 for 638 breast cancer cases who were diagnosed from 1983 to 1993 and 842 controls; we took into account residential mobility and drinking water source. To estimate the historical impact of effluent on drinking water wells, we modified a modular three-dimensional finite-difference groundwater model (MODFLOW) from the U.S. Geological Survey. The analyses included latency and exposure duration. RESULTS. Wastewater effluent impacted the drinking water wells of study participants as early as 1966. For > 0-5 years of exposure (versus no exposure), associations were generally null. Adjusted odds ratios (AORs) for > 10 years of exposure were slightly increased, assuming latency periods of 0 or 10 years [AOR = 1.3; 95% confidence interval (CI), 0.9-1.9 and AOR = 1.6; 95% CI, 0.8-3.2, respectively]. Statistically significant associations were estimated for ever-exposed versus never-exposed women when a 20-year latency period was assumed (AOR = 1.9; 95% CI, 1.0-3.4). A sensitivity analysis that classified exposures assuming lower well-pumping rates showed similar results. CONCLUSION. We investigated the hypothesis generated by earlier spatial analyses that exposure to drinking water contaminated by wastewater effluent may be associated with breast cancer. Using a detailed exposure assessment, we found an association with breast cancer that increased with longer latency and greater exposure duration.National Cancer Institute (5R03CA119703-02); National Institute of Environmental Health Sciences (5P42 ES007381

Genomic Resources for Asparagales

Enormous genomic resources have been developed for plants in the monocot order Poales; however, it is not known how useful these resources will be for other economically important monocots. Asparagales are a monophyletic order sister to class Commelinanae that carries Poales, and is the second most economically important monocot order. Development of genomic resources for and their application to Asparagales are challenging because of huge nuclear genomes and the relatively long generation times required to develop segregating families. We synthesized a normalized eDNA library of onion (Allium cepa) and produced II ,008 unique expressed sequence tags (ESTs) for comparative genomic analyses of Asparagales and Poales. Alignments of onion ESTs, Poales ESTs, and genomic sequences from rice were used to design oligonucleotide primers amplifying genomic regions from asparagus, garlic, and onion. Sequence analyses of these genomic regions revealed microsatellites, insertions/deletions, and single nucleotide polymorphisms for comparative mapping of rice and Asparagales vegetables. Initial mapping revealed no obvious synteny at the recombinationallevel between onion and rice, indicating that genomic resources developed for Poales may not be applicable to the monocots as a whole. Genomic analyses of Asparagales would greatly benefit from EST sequencing and deep-coverage, large-insert genomic libraries of representative small-genome model species within the higher and lower Asparagales, such as asparagus and orchid, respectively

Broadband optical supercontinuum generation in a long cavity fibre laser

We describe optical supercontinuum generation in an actively mode-locked fibre ring laser using a pulsed mode-locking technique. Recirculation of a section of the continuum facilitated spectral broadening

Ge-Doped microstructured multicorefiber for customizable supercontinuum generation

Supercontinuum generation in a multicore fiber in which several uncoupled cores were doped with dissimilar concentrations of germanium was studied experimentally. Germanium doping provided control over the separation between the zero-dispersion wavelength and the 1064-nm wavelength of a Q-switched Nd:YAG pump laser. Supercontinua generated independently in each core of the same piece of fiber displayed clear and repeatable differences due to the influence of germanium doping on refractive index and four-wave mixing. The spectral evolution of the subnanosecond pump pulses injected into the different cores was accurately reproduced by numerical simulations

“You know that's a rip-off”: policies and practices surrounding micro-enterprises and poverty alleviation in South African township tourism

Supporting the development of small tourism businesses has been seen by policy-makers as a valuable means of alleviating poverty in South African townships. This perspective has been endorsed by several ‘responsible’ tourism businesses and academics. Following a review of the literature, this paper reports the findings of an empirical study that examined the practices of micro-business owners and the factors that shape their behaviour in two South African townships. In spite of significant visitor numbers, it finds that their narrow social networks and the imbalances of power between them and intermediaries such as travel agencies and tour operators prevent them from developing their businesses and sharing in the material gains that become available because of tourism. This analysis has important implications for local policy-makers and those advocating responsible tourism. For the former, it suggests a cessation of current initiatives in favour of greater regulation and alternative forms of investment. For the latter, it implies the need to reassess the utility of advocating responsible tourism to consumers in a context where they do not understand the dynamics which fashion what is on offer or the full implications of their choices

High throughput generation of promoter reporter (GFP) transgenic lines of low expressing genes in Arabidopsis and analysis of their expression patterns

<p>Abstract</p> <p>Background</p> <p>Although the complete genome sequence and annotation of Arabidopsis were released at the end of year 2000, it is still a great challenge to understand the function of each gene in the Arabidopsis genome. One way to understand the function of genes on a genome-wide scale is expression profiling by microarrays. However, the expression level of many genes in Arabidopsis genome cannot be detected by microarray experiments. In addition, there are many more novel genes that have been discovered by experiments or predicted by new gene prediction programs. Another way to understand the function of individual genes is to investigate their <it>in vivo </it>expression patterns by reporter constructs in transgenic plants which can provide basic information on the patterns of gene expression.</p> <p>Results</p> <p>A high throughput pipeline was developed to generate promoter-reporter (GFP) transgenic lines for Arabidopsis genes expressed at very low levels and to examine their expression patterns <it>in vivo</it>. The promoter region from a total of 627 non- or low-expressed genes in Arabidopsis based on Arabidopsis annotation release 5 were amplified and cloned into a Gateway vector. A total of 353 promoter-reporter (GFP) constructs were successfully transferred into Agrobacterium (GV3101) by triparental mating and subsequently used for Arabidopsis transformation. Kanamycin-resistant transgenic lines were obtained from 266 constructs and among them positive GFP expression was detected from 150 constructs. Of these 150 constructs, multiple transgenic lines exhibiting consistent expression patterns were obtained for 112 constructs. A total 81 different regions of expression were discovered during our screening of positive transgenic plants and assigned Plant Ontology (PO) codes.</p> <p>Conclusions</p> <p>Many of the genes tested for which expression data were lacking previously are indeed expressed in Arabidopsis during the developmental stages screened. More importantly, our study provides plant researchers with another resource of gene expression information in Arabidopsis. The results of this study are captured in a MySQL database and can be searched at <url>http://www.jcvi.org/arabidopsis/qpcr/index.shtml</url>. Transgenic seeds and constructs are also available for the research community.</p