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Sample records for risk characterization glycoalkaloids

  1. Characterization and Transcriptional Profile of Genes Involved in Glycoalkaloid Biosynthesis in New Varieties of Solanum tuberosum L.

    PubMed

    Mariot, Roberta Fogliatto; de Oliveira, Luisa Abruzzi; Voorhuijzen, Marleen M; Staats, Martijn; Hutten, Ronald C B; van Dijk, Jeroen P; Kok, Esther J; Frazzon, Jeverson

    2016-02-01

    Before commercial release, new potato (Solanum tuberosum) varieties must be evaluated for content of toxic compounds such as glycoalkaloids (GAs), which are potent poisons. GA biosynthesis proceeds via the cholesterol pathway to α-chaconine and α-solanine. The goal of this study was to evaluate the relationship between total glycoalkaloid (TGA) content and the expression of GAME, SGT1, and SGT3 genes in potato tubers. TGA content was measured by HPLC-MS, and reverse transcription quantitative polymerase chain reactions were performed to determine the relative expression of GAME, SGT1, and SGT3 genes. We searched for cis-elements of the transcription start site using the PlantPAN database. There was a relationship between TGA content and the relative expression of GAME, SGT1, and SGT3 genes in potato tubers. Putative promoter regions showed the presence of several cis-elements related to biotic and abiotic stresses and light. These findings provide an important step toward understanding TGA regulation and variation in potato tubers. PMID:26768994

  2. Potato Glycoalkaloids, Past Present and Future

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The steroidal glycoalkaloids of the potato are naturally occurring specialty metabolites of questionable desirability. Although undoubtedly originating under selection as antifeedants against herbivorous pests, glycoalkaloids no longer function as the primary feeding deterrent. However, due to the...

  3. Glycoalkaloids and calystegine alkaloids in potatoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potatoes contain two classes of alkaloids: the glycoalkaloids and the calystegines. The presence of glycoalkaloids in potatoes and their toxicity has been known for more than a century and much has been written about them. Discovery of the nortropane calystegine alkaloids is more recent, and the k...

  4. Steroidal glycoalkaloids in Solanum chacoense.

    PubMed

    Mweetwa, Alice M; Hunter, Danielle; Poe, Rebecca; Harich, Kim C; Ginzberg, Idit; Veilleux, Richard E; Tokuhisa, James G

    2012-03-01

    Potato (Solanum tuberosum L.), a domesticated species that is the fourth most important world agricultural commodity, requires significant management to minimize the effects of herbivore and pathogen damage on crop yield. A wild relative, Solanum chacoense Bitt., has been of interest to plant breeders because it produces an abundance of novel steroidal glycoalkaloid compounds, leptines and leptinines, which are particularly effective deterrents of herbivory by the Colorado potato beetle (Leptinotarsa decemlineata Say). Biochemical approaches were used in this study to investigate the formation and accumulation of SGAs in S. chacoense. SGA contents were determined in various organs at different stages of organ maturity during a time course of plant development. Leptines and leptinines were the main contributors to the increased levels in SGA concentration measured in the aerial versus the subterranean organs of S. chacoense accession 8380-1. Leptines were not detected in aboveground stolons until the stage where shoots had formed mature chlorophyllous leaves. To gain insights into SGA biosynthesis, the abundance of SGAs and steady-state transcripts of genes coding for enzymes of the central terpene and SGA-specific pathways in various plant organs at anthesis were compared. For two genes of primary terpene metabolism, transcript and SGA abundances were correlated, although with some discrepancies. For genes associated with SGA biosynthesis, transcripts were not detected in some tissues containing SGAs; however these transcripts were detected in the progenitor tissues, indicating the possibility that under our standard growth conditions, SGA biosynthesis is largely limited to highly proliferative tissues such as shoot, root and floral meristems. PMID:22217745

  5. Varietal and environmental effect on the glycoalkaloid content of potato (Solanum tuberosum L.).

    PubMed

    Uppal, D S

    1987-01-01

    The tubers of 14 potato varieties were analysed for glycoalkaloids. The level of glycoalkaloids in tubers of all the varieties analysed are within the safe limits for human consumption. The peels of tuber contained about 60-70% of the total glycoalkaloids present in the whole tuber. The levels of glycoalkaloids in leaves and tubers were correlated (r = 0.865). There was a significant increase in the content of glycoalkaloids in peels of tubers exposed to sunlight. Glycoalkaloid contents increased at the rate of 1.9 mg/100 g fresh weight per day in peels of "Kufri Jyoti" tubers exposed to diffused sunlight. PMID:3507005

  6. Risk characterization: principles and practice.

    PubMed

    Williams, Pamela R D; Paustenbach, Dennis J

    2002-01-01

    In the field of risk assessment, characterizing the nature and magnitude of human health or environmental risks is arguably the most important step in the analytical process. In this step, data on the dose-response relationship of an agent are integrated with estimates of the degree of exposure in a population to characterize the likelihood and severity of risk. Although the purpose of risk characterizations is to make sense of the available data and describe what they mean to a broad audience, this step is often given insufficient attention in health risk evaluations. Too often, characterizations fail to interpret or summarize risk information in a meaningful way, or they present single numerical estimates of risk without an adequate discussion of the uncertainties inherent in key exposure parameters or the dose-response assessment, model assumptions, or analytical limitations. Consequently, many users of risk information have misinterpreted the findings of a risk assessment or have false impressions about the degree of accuracy (or the confidence of the scientist) in reported risk estimates. In this article we collected and integrated the published literature on conducting and reporting risk characterizations to provide a broad, yet comprehensive, analysis of the risk characterization process as practiced in the United States and some other countries. Specifically, the following eight topics are addressed: (1) objective of risk characterization, (2) guidance documents on risk characterization, (3) key components of risk characterizations, (4) toxicity criteria for evaluating health risks, (5) descriptors used to characterize health risks, (6) methods for quantifying human health risks, (7) key uncertainties in risk characterizations, and (8) the risk decision-making process. A brief discussion is also provided on international aspects of risk characterization. A number of examples are presented that illustrate key concepts, and citations are provided for

  7. MANIPULATION AND COMPENSATION OF STEROIDAL GLYCOALKALOID BIOSYNTHESIS IN POTATOES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Steroidal glycoalkaloids (SGAs) are undesirable secondary metabolites produced in Solanaceous plants including, potato, tomato and eggplant. Two tri-glycosylated alkaloids, alpha-chaconine and alpha-solanine occur naturally in potato tubers and can accumulate to excessive levels due to mechanical, e...

  8. Modifying glycoalkaloid content in transgenic potato – Metabolome impacts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Metabolite profiling has been used to assess the potential for unintended composition changes in potato (Solanum tuberosum L. cv. Desirée) tubers, which have been genetically modified (GM) to reduce glycoalkaloid content via the independent down-regulation of three genes SGT1, SGT2 and SGT3 known t...

  9. Potato glycoalkaloids and metabolites: roles in the plant and in the diet.

    PubMed

    Friedman, Mendel

    2006-11-15

    Potatoes, members of the Solanaceae plant family, serve as major, inexpensive low-fat food sources providing energy (starch), high-quality protein, fiber, and vitamins. Potatoes also produce biologically active secondary metabolites, which may have both adverse and beneficial effects in the diet. These include glycoalkaloids, calystegine alkaloids, protease inhibitors, lectins, phenolic compounds, and chlorophyll. Because glycoalkaloids are reported to be involved in host-plant resistance and to have a variety of adverse as well as beneficial effects in cells, animals, and humans, a need exists to develop a clearer understanding of their roles both in the plant and in the diet. To contribute to this effort, this integrated review presents data on the (a) history of glycoalkaloids; (b) glycoalkaloid content in different parts of the potato plant, in processed potato products, and in wild, transgenic, and organic potatoes; (c) biosynthesis, inheritance, plant molecular biology, and glycoalkaloid-plant phytopathogen relationships; (d) dietary significance with special focus on the chemistry, analysis, and nutritional quality of low-glycoalkaloid potato protein; (e) pharmacology and toxicology of the potato glycoalkaloids comprising alpha-chaconine and alpha-solanine and their hydrolysis products (metabolites); (f) anticarcinogenic and other beneficial effects; and (g) possible dietary consequences of concurrent consumption of glycoalkaloids and other biologically active compounds present in fresh and processed potatoes. An enhanced understanding of the multiple and overlapping aspects of glycoalkaloids in the plant and in the diet will benefit producers and consumers of potatoes. PMID:17090106

  10. Distribution of Glycoalkaloids in Potato Tubers of 59 Accessions of Two Wild and Five Cultivated Solanum Species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Steroidal glycoalkaloids are naturally occurring, secondary plant metabolites that are found in foods, including potatoes and tomatoes. Their content in plants is controlled by both genetic and environmental factors. Glycoalkaloid profiles can be passed to progenies during breeding and hybridizati...

  11. [Survey of glycoalkaloids content in the various potatoes].

    PubMed

    Shimoi, Toshiko; Ushiyama, Hirofumi; Kan, Kimiko; Saito, Kazuo; Kamata, Kunihiro; Hirokado, Masako

    2007-06-01

    The content of potato glycoalkaloid (PGA) was investigated in 27 cultivars of raw potatoes and 31 potatoes in commercial foods with peel. The investigation of the 27 cultivars of potatoes showed different contents of glycoalkaloids. "May queen" and "Sherry" showed high contents of PGA (180 mg/kg and 320 mg/kg, respectively) among the raw potatoes of middle size (ca. 100 g). On the other hand, "Inca red" showed the lowest content of 21 mg/kg. Higher contents of PGA were found in smaller potatoes in this study. The content of PGA varied in the range of 48-350 mg/kg in the potatoes in commercial foods with peel. PMID:17658001

  12. Steroidal glycoalkaloids from the berries of Solanum distichum.

    PubMed

    Abouzid, Sameh; Fawzy, Nermeen; Darweesh, Nebal; Orihara, Yutaka

    2008-01-20

    Two steroidal glycoalkaloids, Solanidine 3-O-[alpha-L-rhamnopyranosyl-(1'' --> 4)-[alpha-L-rhamnopyranosyl-(1' --> 2)]-beta-D-glucopyranoside] (1) and Solanidine 3-O-[alpha-L-rhamnopyranosyl-(1'' --> 4)-beta-D-glucopyranoside] (2) commonly known as alpha-chanonine and beta 2-chanonine, were isolated from the berries of Solanum distichum. The structures of the isolated compounds were studied by 1D and 2D NMR techniques and FAB MS analysis. The 13C NMR signal assignments and direct elucidation of the glycoside linkages were established. Glycoalkaloids level in the dried berries, determined by a simple colorimetric method, was found to be 5.08 +/- 0.18 g%. PMID:18075898

  13. Modifying glycoalkaloid content in transgenic potato--Metabolome impacts.

    PubMed

    Shepherd, Louise Vida Traill; Hackett, Christine Anne; Alexander, Colin James; McNicol, James William; Sungurtas, Julia Anne; Stewart, Derek; McCue, Kent Frank; Belknap, William Richardson; Davies, Howard Vivian

    2015-11-15

    Metabolite profiling has been used to assess the potential for unintended composition changes in potato (Solanum tuberosum L. cv. Desirée) tubers, which have been genetically modified (GM) to reduce glycoalkaloid content, via the independent down-regulation of three genes SGT1, SGT2 and SGT3 known to be involved in glycoalkaloid biosynthesis. Differences between the three groups of antisense lines and control lines were assessed using liquid chromatography-mass spectrometry (LC-MS) and gas chromatography (GC)-MS, and data analysed using principal component analysis and analysis of variance. Compared with the wild-type (WT) control, LC-MS revealed not only the expected changes in specific glycoalkaloid levels in the GM lines, but also significant changes in several other metabolites, some of which were explicable in terms of known pathways. Analysis of polar and non-polar metabolites by GC-MS revealed other significant (unintended) differences between SGT lines and the WT, but also between the WT control and other control lines used. PMID:25977048

  14. Steroidal glycoalkaloid content of potato, tomato and their somatic hybrids.

    PubMed

    Roddick, J G; Melchers, G

    1985-09-01

    Analyses of leaves and 'tubers' from somatic hybrids of potato and tomato ('pomato' with plastids of potato, 'topato' with plastids of tomato) produced by fusion of protoplasts from liquid cultures of dihaploid potato and mesophyll of tomato revealed the presence of the two major potato glycoalkaloids (α-solanine and α-chaconine) as well as the tomato glycoalkaloid (αtomatine). The total alkaloid content of leaves was greater than that of 'tubers' and similar to levels in the foliage of parent plants. However, glycoalkaloids were more abundant in hybrid 'tubers' than in normal potato tubers by a factor of 5-15. In hybrid foliage, approximately 98% of the alkaloid present was of potato origin whereas in 'tubers' the reverse was the case, with tomatine comprising 60-70% of the total alkaloid. The similarities in alkaloid content and ratios between the pomato and the topato lines indicate that plastomes do not influence the biosynthesis and distribution of these alkaloids. The results indicate that major secondary metabolites may prove useful for assessing the hybrid nature of such plants. PMID:24253124

  15. Polyphenol and glycoalkaloid contents in potato cultivars grown in Luxembourg.

    PubMed

    Deusser, Hannah; Guignard, Cédric; Hoffmann, Lucien; Evers, Danièle

    2012-12-15

    The polyphenol (phenolic acids, flavanols and flavonols) and glycoalkaloid (α-chaconine and α-solanine) contents of potato tubers grown in Luxembourg were analyzed by UPLC-DAD and HPLC-MS/MS separately in peel (approx. 2mm), outer (approx. 1cm) and inner flesh. Polyphenol contents decreased from the peel via the outer to the inner flesh and differed among the cultivars. The cultivars Vitelotte and Luminella had the highest polyphenol contents (5202 and 572 μg/g dry weight (DW) in the outer flesh), whereas Charlotte and Bintje had the lowest contents (19.5 and 48.0 μg/g DW). Chlorogenic acid and its isomers (neo- and cryptochlorogenic acid) were the major polyphenols. Glycoalkaloid contents were highest in the peel and lowest in the inner flesh, values in the flesh were below guideline limits in all cultivars. In conclusion, potatoes contribute to the daily intake of polyphenols and their consumption, thereby, may have positive effects on health. PMID:22980877

  16. The chemistry and anticarcinogenic mechanisms of glycoalkaloids produced by eggplants, potatoes, and tomatoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inhibition of cancer can occur via apoptosis, a genetically directed process of cell self-destruction that involves numerous biomarkers and signaling pathways. Glycoalkaloids are nitrogen-containing secondary plant metabolites found in numerous Solanaceous plants including eggplants, potatoes, and ...

  17. Effects of the extract and glycoalkaloids of Solanum lycocarpum St. Hill on Giardia lamblia trophozoites

    PubMed Central

    Martins, Gilmarcio Z.; Moreira, Raquel R. D.; Planeta, Cleopatra S.; Almeida, Adélia E.; Bastos, Jairo K.; Salgueiro, Lígia; Cavaleiro, Carlos; do Céu Sousa, Maria

    2015-01-01

    Background: Solanum lycocarpum has great importance for food and medicinal traditional use. Recently, it was also evidenced that extracts of S. lycocarpum St. Hill (Solanaceae) and its glycoalkaloids, solamargine (Sg) and solasonine (Sn), are active against flagellated protozoa. Objective: The aim was to assess the effects of the extract of S. lycocarpum and its glycoalkaloids, Sn, and Sg, on Giardia lamblia trophozoites. Materials and Methods: A crude extract (96%ethanol) (EB) of fruits of S. lycocarpum was prepared and fractionated by partition with 40%ethanol and n-hexane: Ethyl acetate. Glycoalkaloids, Sn, and Sg were recognized in the ethanol fraction (EF) and further isolated by column chromatography. EB, EF, the isolated Sn and Sg and a mixture (1:1) of both glycoalkaloids were tested on cultures of G. lamblia trophozoites and macrophages. Results: EB, EF and glycoalkaloids of S. lycocarpum showed activity against Giardia (95.0 < Inhibitory concentration 50 [IC50] ≤120.3 μg/mL). The mixture of glycoalkaloids (1:1) was more active (IC50 = 13.23 μg/mL) than each one individually, suggesting a synergic effect. Moreover, the mixture is nontoxic to macrophage cells. Conclusion: Results are optimistic concerning the anti-Giardia potential of the mixture Sn + Sg. Further studies, in vitro and in vivo, will be required to consolidate the usefulness of the mixture of Sn + Sg in view of a new therapeutic strategy for giardiasis. PMID:26109762

  18. CHARACTERIZATION OF RISKS POSED BY COMBUSTOR EMISSIONS

    EPA Science Inventory

    Risk characterization is the final step of the risk assessment process as practiced in the U.S. EPA. In risk characterization, the major scientific evidence and "bottom-line" results from the other components of the risk assessment process, hazard identification, dose-response as...

  19. Cardioactive properties of Solanaceae plant extracts and pure glycoalkaloids on Zophobas atratus.

    PubMed

    Ventrella, Emanuela; Marciniak, Paweł; Adamski, Zbigniew; Rosiński, Grzegorz; Chowański, Szymon; Falabella, Patrizia; Scrano, Laura; Bufo, Sabino A

    2015-04-01

    Glycoalkaloids, the biologically active secondary metabolites produced by Solanaceae plants, are natural defenses against animals, insects and fungi. In this paper, the effects of glycoalkaloids present in extracts of Solanaceae plants (potato, tomato and black nightshade) or pure commercial glycoalkaloids on the coleopteran Zophobas atratus F. were evaluated by in vitro and in vivo bioassays using heart experimental models. Each tested extract induced a dose-dependent cardioinhibitory effect. The perfusion of Zophobas atratus semi-isolated heart using the highest potato and tomato extract concentration (1 mmol/L) caused irreversible cardiac arrests, while extract from black nightshade produced fast but reversible arrests. Pure commercial glycoalkaloids caused similar but less evident effects compared with extracts. Our results showed that the bioactivity of tested compounds depended on their structure and suggested the existence of synergistic interactions when combinations of the main glycoalkaloids of potato and black nightshade were used for trials. Surprisingly, injection of tomato and potato extracts in 1-day-old pupae of Zophobas atratus induced reversible positive chronotropic effects and decreased the duration of the both phases (anterograde and retrograde) of the heart contractile activity. Furthermore, these extracts affected the amplitude of the heart contractions. PMID:24470045

  20. Glycoalkaloids in potato tubers grown under controlled environments

    NASA Technical Reports Server (NTRS)

    Nitithamyong, A.; Vonelbe, J. H.; Wheeler, R. M.; Tibbitts, T. W.

    1999-01-01

    Tuber content of alpha-solanine, alpha-chaconine, and total glycoalkaloids (TGA) was determined for the potato cultivars, Norland, Russet Burbank, and Denali grown under different environmental conditions in growth chambers. The lowest TGA concentrations (0.30 to 0.35 mg g-1 dry tissue) were found in the cv. Norland with 400 micromoles m-2 s-1 photosynthetic photon flux (PPF), 12 h day length, 16 C temperature, and 350 micromoles mol-1 carbon dioxide. The ratio of alpha-chaconine to alpha-solanine was close to 60:40 under all growing conditions, except that it was 50:50 under the low temperature of 12 C. Cultivars responded similarly to environmental conditions although TGA was about 20% greater in cv. Russet Burbank and about 30% greater in Denali compared to Norland. The largest changes in TGA occurred with changes in temperature. In comparison to 16 C, TGA were 40% greater at 12 C, 80% greater at 20 C, and 125% greater at 24 C (0.70 mg g-1 dry weight). The TGA concentration increased from 10 to 25% with an increase in light from 400 to 800 micromoles m-2 s-1 PPF for all three cultivars. TGA increased 20% with extension of the day length from 12 to 24 hr and also increased 20% when carbon dioxide was increased from 350 to 1000 micromoles mol-1. TGA concentrations were not influenced by changes in relative humidity from 50 to 80%. TGA concentrations decreased only slightly in harvests made from 9 to 21 weeks after planting. Variations in TGA among the different growing conditions and cultivars were below 20 mg/100 g fresh weight (approximately 1.0 mg g-1 dry weight) recognized as the upper concentration for food safety. However the results suggest that TGA should be considered when potatoes are grown at temperatures above 20 C.

  1. Two Cytochrome P450 Monooxygenases Catalyze Early Hydroxylation Steps in the Potato Steroid Glycoalkaloid Biosynthetic Pathway.

    PubMed

    Umemoto, Naoyuki; Nakayasu, Masaru; Ohyama, Kiyoshi; Yotsu-Yamashita, Mari; Mizutani, Masaharu; Seki, Hikaru; Saito, Kazuki; Muranaka, Toshiya

    2016-08-01

    α-Solanine and α-chaconine, steroidal glycoalkaloids (SGAs) found in potato (Solanum tuberosum), are among the best-known secondary metabolites in food crops. At low concentrations in potato tubers, SGAs are distasteful; however, at high concentrations, SGAs are harmful to humans and animals. Here, we show that POTATO GLYCOALKALOID BIOSYNTHESIS1 (PGA1) and PGA2, two genes that encode cytochrome P450 monooxygenases (CYP72A208 and CYP72A188), are involved in the SGA biosynthetic pathway, respectively. The knockdown plants of either PGA1 or PGA2 contained very little SGA, yet vegetative growth and tuber production were not affected. Analyzing metabolites that accumulated in the plants and produced by in vitro enzyme assays revealed that PGA1 and PGA2 catalyzed the 26- and 22-hydroxylation steps, respectively, in the SGA biosynthetic pathway. The PGA-knockdown plants had two unique phenotypic characteristics: The plants were sterile and tubers of these knockdown plants did not sprout during storage. Functional analyses of PGA1 and PGA2 have provided clues for controlling both potato glycoalkaloid biosynthesis and tuber sprouting, two traits that can significantly impact potato breeding and the industry. PMID:27307258

  2. Glycoalkaloid development during greening of fresh market potatoes (Solanum tuberosum L.).

    PubMed

    Grunenfelder, Laura A; Knowles, Lisa O; Hiller, Larry K; Knowles, N Richard

    2006-08-01

    Chlorophyll and glycoalkaloid synthesis in potato (Solanum tuberosum L.) tubers occur in direct response to light. The two processes are concurrent, but independent. Color photographic indices to subjectively grade fresh market potatoes for the extent of greening were developed under lighting conditions consistent with those of retail markets. Total glycoalkaloid (TGA) and chlorophyll accumulation for four cultivars were determined over the respective greening scales, thus calibrating the scales for TGA content. On average, TGA concentrations in complete longitudinal sections of tubers (flesh samples) were highest in Dark Red Norland followed by Russet Norkotah, Yukon Gold, and White Rose. TGA concentrations of flesh samples of White Rose and Yukon Gold tubers were somewhat variable and did not increase in direct proportion to greening level and chlorophyll content, particularly at higher levels of greening. TGA concentrations in Dark Red Norland and Russet Norkotah tubers were highly correlated (P < or = 0.001) with greening level and chlorophyll concentrations. When averaged over greening levels, skin samples contained 3.4- to 6.8-fold higher concentrations of TGAs than flesh samples, depending on the cultivar. The TGA concentration in periderm samples ranged from 37 to 160 mg/100 g of dry wt. Regardless of greening level, concentrations of TGAs in the flesh samples (including attached periderm) remained within limits presumed safe for human consumption. Discrimination of greened tubers on the basis of perceived glycoalkaloid toxicity is likely unfounded for the cultivars and greening levels studied. PMID:16881686

  3. Probabilistic Exposure Analysis for Chemical Risk Characterization

    PubMed Central

    Bogen, Kenneth T.; Cullen, Alison C.; Frey, H. Christopher; Price, Paul S.

    2009-01-01

    This paper summarizes the state of the science of probabilistic exposure assessment (PEA) as applied to chemical risk characterization. Current probabilistic risk analysis methods applied to PEA are reviewed. PEA within the context of risk-based decision making is discussed, including probabilistic treatment of related uncertainty, interindividual heterogeneity, and other sources of variability. Key examples of recent experience gained in assessing human exposures to chemicals in the environment, and other applications to chemical risk characterization and assessment, are presented. It is concluded that, although improvements continue to be made, existing methods suffice for effective application of PEA to support quantitative analyses of the risk of chemically induced toxicity that play an increasing role in key decision-making objectives involving health protection, triage, civil justice, and criminal justice. Different types of information required to apply PEA to these different decision contexts are identified, and specific PEA methods are highlighted that are best suited to exposure assessment in these separate contexts. PMID:19223660

  4. Composition of phenolic compounds and glycoalkaloids alpha-solanine and alpha-chaconine during commercial potato processing.

    PubMed

    Mäder, Jens; Rawel, Harshadrai; Kroh, Lothar W

    2009-07-22

    The influence of a commercial production process for dehydrated potato flakes on the content of free phenolic compounds, total phenolics, and glycoalkaloids in potatoes during the subsequent processing steps was determined. Processing byproducts, such as potato peel (steam peeling), mashed potato residues, and side streams (blanching and cooking waters), have also been investigated. A high-performance liquid chromatography (HPLC) method was developed to separate and quantify caffeic acid, gallic acid, ferulic acid, p-coumaric acid, p-hydoxybenzoic acid, protocatechuic acid, vanillic acid, catechin, and three isomers of caffeoylquinic acid: chlorogenic, neochlorogenic and cryptochlorogenic acid. Determination of the glycoalkaloids alpha-solanine and alpha-chaconine was performed by using a high-performance thin-layer chromatography (HPTLC) method. The deliverables reveal that processing potatoes to potato flakes remarkably diminishes the content of the analyzed compounds, mainly due to peeling and leaching. The influence of thermal exposure is less significant. About 43% of the initial phenolic acids and 10% of the glycoalkaloids remain after processing. The results of the total phenolic content assay by Folin-Ciocalteu reagent are proportional to the content of phenolic compounds determined by HPLC. Steam peeling has a higher influence on glycoalkaloid losses compared to that on phenolics. The highest amounts of phenolic compounds and glycoalkaloids were found in peeling byproduct. During processing, the amount of chlorogenic acid decreased, whereas the concentration of neochlorogenic acid increased due to isomerization. The impact of the results on potato processing technology is discussed. PMID:19534529

  5. Chemistry and anticarcinogenic mechanisms of glycoalkaloids produced by eggplants, potatoes, and tomatoes.

    PubMed

    Friedman, Mendel

    2015-04-01

    Inhibition of cancer can occur via apoptosis, a genetically directed process of cell self-destruction that involves numerous biomarkers and signaling pathways. Glycoalkaloids are nitrogen-containing secondary plant metabolites found in numerous Solanaceous plants including eggplants, potatoes, and tomatoes. Exposure of cancer cells to glycoalkaloids produced by eggplants (α-solamargine and α-solasonine), potatoes (α-chaconine and α-solanine), and tomatoes (α-tomatine) or their hydrolysis products (mono-, di-, and trisaccharide derivatives and the aglycones solasodine, solanidine, and tomatidine) inhibits the growth of the cells in culture (in vitro) as well as tumor growth in vivo. This overview comprehensively surveys and consolidates worldwide efforts to define the following aspects of these natural compounds: (a) their prevalence in the three foods; (b) their chemistry and structure-activity relationships; (c) the reported factors (biomarkers, signaling pathways) associated with apoptosis of bone, breast, cervical, colon, gastric, glioblastoma, leukemia, liver, lung, lymphoma, melanoma, pancreas, prostate, and squamous cell carcinoma cell lines in vitro and the in vivo inhibition of tumor formation and growth in fish and mice and in human skin cancers; and (d) future research needs. The described results may make it possible to better relate the structures of the active compounds to their health-promoting function, individually, in combination, and in food, and allow the consumer to select glycoalkaloid-containing food with the optimal content of nontoxic beneficial compounds. The described findings are expected to be a valuable record and resource for further investigation of the health benefits of food-related natural compounds. PMID:25821990

  6. Bioassay-guided fractionation of extracts from Easter lily (Lilium longiflorum) flowers reveals unprecedented structural variability of steroidal glycoalkaloids.

    PubMed

    Uhlig, Silvio; Hussain, Fozia; Wisløff, Helene

    2014-12-15

    Several Lilium species are nephrotoxic in cats (Felis silvestris catus), among them Easter lilies (Lilium longiflorum). Although clinical trials have been carried out, the causative toxic phytochemicals have not yet been identified. We thus aimed to determine the toxic constituents of Easter lily flowers applying a bioassay-guided approach based on a feline kidney cell line model. The bioassay-guided fractionation traced the observed cytotoxicity to a complex mixture of compounds that were tentatively identified as steroidal glycoalkaloids of the solasodine-type, based on multiple-fragmentation ion trap and high-resolution mass spectrometry. The glycoalkaloids in the active fraction possessed trisaccharide chains, and at least 16 different congeners could be separated using liquid chromatography-mass spectrometry. The two principal compounds were solasodine trisaccharides containing two hexose and one deoxy-hexose unit. In the remaining 14 analogues, one or two of the hydroxyl groups of the second hexose from the aglycone were acetylated. In addition, some of the analogues appeared to be carbonate esters. Esterification of steroidal glycoalkaloids in plants has only been reported once and was in accordance with higher antifungal activity of the acetylated versus the parent congener. Our pilot study shows that esterification of steroidal glycoalkaloids in Lilium species might be common resulting in an array of different analogues with largely unexplored structural variability and bioactivity. PMID:25269117

  7. Structure of two solanum tuberosum steroidal glycoalkaloid glycosyltransferase genes and expression of their promoters in transgenic potatoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Sgt2 gene in potato encodes a solanidine glucosyltransferase and is present as two distinct alleles expressed in cultivated potatoes. Promoter regions upstream from both steroidal glycoalkaloid biosynthetic gene alleles, Sgt2.1 and Sgt2.2, were isolated from Solanum tuberosum cv. Russet Burbank ...

  8. Impact of light-exposure on the metabolite balance of transgenic potato tubers with modified glycoalkaloid biosynthesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Metabolite profiling has been used to assess the impact of light exposure on the composition of potato (Solanum tuberosum L. cv. Desirée) tubers genetically modified (GM) to reduce glycoalkaloid (specifically a-solanine) content via the down-regulation of the SGT1 gene. Using a combination of liq...

  9. Glycoalkaloid levels in potato tubers and leaves after intermittent plant exposure to ozone

    SciTech Connect

    Speroni, J.J.; Pell, E.J.; Weissberger, W.C.

    1981-01-01

    Irish potato vines of Norland and Kennebec cultivars were exposed to 387 ..mu..g/m/sup 3/ ozone for 3 hr once every wk throughout their growth. Tubers of Norland and Kennebec were harvested at 120 and 140 days, respectively, from exposed and non-exposed plants. The experiment was conducted in 1977 and again in 1978. Ozone induced severe foliar injury to Norland and slight injury to leaves of Kennebec. Tubers from ozone treated plants displayed a significant reduction (0.35 mg TTGA/100 g fresh weight tuber tissue) in tuber total glycoalkaloids (TTGA) when expressed on a fresh weight basis. However, since differences were not detected for TTGA on a dry-weight basis, the fresh-weight TTGA differences may only reflect variations in moisture content. In a separate experiment, both Norland and Kennebec were exposed to 488 ..mu..g/m/sup 3/ ozone for 3 hr when the plants were 18 days old. When leaves were harvested three days later, no significant differeces were detected between leaf total glycoalkaloid (LTGA) levels of treated and nontreated plants. 26 references, 2 tables.

  10. The challenge of risk characterization: current practice and future directions.

    PubMed Central

    Gray, G M; Cohen, J T; Graham, J D

    1993-01-01

    Risk characterization is perhaps the most important part of risk assessment. As currently practiced, risk characterizations do not convey the degree of uncertainty in a risk estimate to risk managers, Congress, the press, and the public. Here, we use a framework put forth by an ad hoc study group of industry and government scientists and academics to critique the risk characterizations contained in two risks assessments of gasoline vapor. After discussing the strengths and weaknesses of each assessment's risk characterization, we detail an alternative approach that conveys estimates in the form of a probability distribution. The distributional approach can make use of all relevant scientific data and knowledge, including alternative data sets and all plausible mechanistic theories of carcinogenesis. As a result, this approach facilitates better public health decisions than current risk characterization procedures. We discuss methodological issues, as well as strengths and weaknesses of the distributional approach. PMID:8020444

  11. Characterizing bioaerosol risk from environmental sampling.

    PubMed

    Hong, Tao; Gurian, Patrick L

    2012-06-19

    In the aftermath of a release of microbiological agents, environmental sampling must be conducted to characterize the release sufficiently so that mathematical models can then be used to predict the subsequent dispersion and human health risks. Because both the dose-response and environmental transport of aerosolized microbiological agents are functions of the effective aerodynamic diameter of the particles, environmental assessments should consider not only the total amount of agents but also the size distributions of the aerosolized particles. However, typical surface sampling cannot readily distinguish among different size particles. This study evaluates different approaches to estimating risk from measurements of microorganisms deposited on surfaces after an aerosol release. For various combinations of sampling surfaces, size fractions, HVAC operating conditions, size distributions of release spores, uncertainties in surface measurements, and the accuracy of model predictions are tested in order to assess how much detail can realistically be identified from surface sampling results. The recommended modeling and sampling scheme is one choosing 3, 5, and 10 μm diameter particles as identification targets and taking samples from untracked floor, wall, and the HVAC filter. This scheme provides reasonably accurate, but somewhat conservative, estimates of risk across a range of different scenarios. Performance of the recommended sampling scheme is tested by using data from a large-scale field test as a case study. Sample sizes of 10-25 in each homogeneously mixed environmental compartment are sufficient to develop order of magnitude estimates of risk. Larger sample sizes have little benefit unless uncertainties in sample recoveries can be reduced. PMID:22568610

  12. Isolation, identification and quantification of unsaturated fatty acids, amides, phenolic compounds and glycoalkaloids from potato peel.

    PubMed

    Wu, Zhi-Gang; Xu, Hai-Yan; Ma, Qiong; Cao, Ye; Ma, Jian-Nan; Ma, Chao-Mei

    2012-12-15

    Eleven compounds were isolated from potato peels and identified. Their structures were determined by interpretation of UV, MS, 1D, and 2D NMR spectral data and by comparison with reported data. The main components of the potato peels were found to be chlorogenic acid and other phenolic compounds, accompanied by 2 glycoalkaloids, 3 low-molecular-weight amide compounds, and 2 unsaturated fatty acids, including an omega-3 fatty acid. The potato peels showed more potent radical scavenging activity than the flesh. The quantification of the 11 components indicated that the potato peels contained a higher amount of phenolic compounds than the flesh. These results suggest that peel waste from the industry of potato chips and fries may be a source of useful compounds for human health. PMID:22980823

  13. Electrochemical Determination of Glycoalkaloids Using a Carbon Nanotubes-Phenylboronic Acid Modified Glassy Carbon Electrode

    PubMed Central

    Wang, Huiying; Liu, Mingyue; Hu, Xinxi; Li, Mei; Xiong, Xingyao

    2013-01-01

    A versatile strategy for electrochemical determination of glycoalkaloids (GAs) was developed by using a carbon nanotubes-phenylboronic acid (CNTs-PBA) modified glassy carbon electrode. PBA reacts with α-solanine and α-chaconine to form a cyclic ester, which could be utilized to detect GAs. This method allowed GA detection from 1 μM to 28 μM and the detection limit was 0.3 μM. Affinity interaction of GAs and immobilized PBA caused an essential change of the peak current. The CNT-PBA modified electrodes were sensitive for detection of GAs, and the peak current values were in quite good agreement with those measured by the sensors. PMID:24287539

  14. Spiralosides A-C, Three New C27-Steroidal Glycoalkaloids from the Fruits of Solanum spirale.

    PubMed

    Li, Dan; Zhao, Yun-Li; Qin, Xu-Jie; Liu, Lu; Yang, Xing-Wei; Chen, Ying-Ying; Wang, Bei; Wei, Xin; Liu, Ya-Ping; Luo, Xiao-Dong

    2016-08-01

    Three new C27-steroidal glycoalkaloids, spiralosides A-C (1-3), were obtained from the total alkaloids of Solanum spirale by chromatographic methods. On the basis of spectroscopic evidence, spiralosides A-C were elucidated as (22R,25S)-22,26-epiminocholest-5-ene-3β,16α-diol-N-acetyl-3-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl (1), (22R,25S)-22,26-epiminocholest-5-ene-3β,16α-diol-N-acetyl-3-O-β-D-glucopyranosyl (2), (22R,25S)-22,26-epiminocholest-3β,16α-diol-N-acetyl-3-O-β-D-glucopyranosyl (3), respectively. The total alkaloids of S. spirale have been screened for their antitussive and expectorant effects in intact animal model. PMID:27318495

  15. Sapphire statistical characterization and risk reduction program

    NASA Astrophysics Data System (ADS)

    McClure, Donald R.; Cayse, Robert; Black, David R.; Goodrich, Steven M.; Lagerloef, K. Peter D.; Harris, Daniel C.; McCullum, Dale; Platus, Daniel H.; Patty, Charles E., Jr.; Polvani, Robert S.

    2001-09-01

    The Sapphire Statistical Characterization and Risk Reduction Program tested 1400 4-point flexure bars with different crystal orientations at different temperatures to establish a mechanical strength database for engineering design. Sapphire coupons were selected to represent surfaces on two different missile windows and a missile dome. Sapphire was obtained from the same suppliers used for the windows or dome and, as much as possible, coupons were fabricated in the same manner as the corresponding part of the window or dome. For one missile window, sapphire from one fabricator was 50% stronger than sapphire made to the same specifications from the same blanks by another fabricator. In laser thermal shock tests, sapphire performed better than predicted from flexure tests. Of several nondestructive methods evaluated for their ability to identify mechanically weak specimens, only x-ray topography was correlated with strength for a limited set of specimens.

  16. Two Cytochrome P450 Monooxygenases Catalyze Early Hydroxylation Steps in the Potato Steroid Glycoalkaloid Biosynthetic Pathway1[OPEN

    PubMed Central

    Nakayasu, Masaru; Ohyama, Kiyoshi; Saito, Kazuki

    2016-01-01

    α-Solanine and α-chaconine, steroidal glycoalkaloids (SGAs) found in potato (Solanum tuberosum), are among the best-known secondary metabolites in food crops. At low concentrations in potato tubers, SGAs are distasteful; however, at high concentrations, SGAs are harmful to humans and animals. Here, we show that POTATO GLYCOALKALOID BIOSYNTHESIS1 (PGA1) and PGA2, two genes that encode cytochrome P450 monooxygenases (CYP72A208 and CYP72A188), are involved in the SGA biosynthetic pathway, respectively. The knockdown plants of either PGA1 or PGA2 contained very little SGA, yet vegetative growth and tuber production were not affected. Analyzing metabolites that accumulated in the plants and produced by in vitro enzyme assays revealed that PGA1 and PGA2 catalyzed the 26- and 22-hydroxylation steps, respectively, in the SGA biosynthetic pathway. The PGA-knockdown plants had two unique phenotypic characteristics: The plants were sterile and tubers of these knockdown plants did not sprout during storage. Functional analyses of PGA1 and PGA2 have provided clues for controlling both potato glycoalkaloid biosynthesis and tuber sprouting, two traits that can significantly impact potato breeding and the industry. PMID:27307258

  17. RISK-INFORMED SAFETY MARGIN CHARACTERIZATION

    SciTech Connect

    Nam Dinh; Ronaldo Szilard

    2009-07-01

    The concept of safety margins has served as a fundamental principle in the design and operation of commercial nuclear power plants (NPPs). Defined as the minimum distance between a system’s “loading” and its “capacity”, plant design and operation is predicated on ensuring an adequate safety margin for safety-significant parameters (e.g., fuel cladding temperature, containment pressure, etc.) is provided over the spectrum of anticipated plant operating, transient and accident conditions. To meet the anticipated challenges associated with extending the operational lifetimes of the current fleet of operating NPPs, the United States Department of Energy (USDOE), the Idaho National Laboratory (INL) and the Electric Power Research Institute (EPRI) have developed a collaboration to conduct coordinated research to identify and address the technological challenges and opportunities that likely would affect the safe and economic operation of the existing NPP fleet over the postulated long-term time horizons. In this paper we describe a framework for developing and implementing a Risk-Informed Safety Margin Characterization (RISMC) approach to evaluate and manage changes in plant safety margins over long time horizons.

  18. Characterizing Determinants of Risk: Concentration, Duration, and Timing of Exposure

    EPA Science Inventory

    An ongoing challenge in human health risk assessment is to determine the best approach for characterizing the risk from real-world exposures. Three major determinants characterize exposure: concentration (how much), duration (the frequency and how long), and critical timing (whe...

  19. Comparison of rapid liquid chromatography-electrospray ionization-tandem mass spectrometry methods for determination of glycoalkaloids in transgenic field-grown potatoes.

    PubMed

    Zywicki, Britta; Catchpole, Gareth; Draper, John; Fiehn, Oliver

    2005-01-15

    Two rapid methods for highly selective detection and quantification of the two major glycoalkaloids in potatoes, alpha-chaconine and alpha-solanine, were compared for robustness in high-throughput operations for over 1000 analytical runs using potato tuber samples from field trials. Glycoalkaloids were analyzed using liquid chromatography coupled to tandem mass spectrometry in multiple reaction monitoring mode. An electrospray interface was used in the detection of glycoalkaloids in positive ion mode. Classical reversed phase (RP) and hydrophilic interaction (HILIC) columns were investigated for chromatographic separation, ruggedness, recovery, precision, and accuracy. During the validation procedure both methods proved to be precise and accurate enough in relation to the high degree of endogenous biological variability found for field-grown potato tubers. However, the RP method was found to be more precise, more accurate, and, more importantly, more rugged than the HILIC method for maintaining the analytes' peak shape symmetry in high-throughput operation. When applied to the comparison of six classically bred potato cultivars to six genetically modified (GM) lines engineered to synthesize health beneficial inulins, the glycoalkaloid content in potato peels of all GM lines was found within the range of the six cultivars. We suggest complementing current unbiased metabolomic strategies by validating quantitative analytical methods for important target analytes such as the toxic glycoalkaloids in potato plants. PMID:15620882

  20. Detection of glycoalkaloids using disposable biosensors based on genetically modified enzymes.

    PubMed

    Espinoza, Michelle Arredondo; Istamboulie, Georges; Chira, Ana; Noguer, Thierry; Stoytcheva, Margarita; Marty, Jean-Louis

    2014-07-15

    In this work we present a rapid, selective, and highly sensitive detection of α-solanine and α-chaconine using cholinesterase-based sensors. The high sensitivity of the devices is brought by the use of a genetically modified acetylcholinesterase (AChE), combined with a one-step detection method based on the measurement of inhibition slope. The selectivity was obtained by using butyrylcholinesterase (BChE), an enzyme able to detect these two toxins with differential inhibition kinetics. The enzymes were immobilized via entrapment in PVA-AWP polymer directly on the working electrode surface. The analysis of the resulting inhibition slope was performed employing linear regression function included in Matlab. The high toxicity of α-chaconine compared to α-solanine due to a better affinity to the active site was proved. The inhibition of glycoalkaloids (GAs) mixture was performed over AChE enzyme wild-type AChE and BChE biosensors resulting in the detection of synergism effect. The developed method allows the detection of (GAs) at 50 ppb in potato matrix. PMID:24747413

  1. Jasmonate-Responsive ERF Transcription Factors Regulate Steroidal Glycoalkaloid Biosynthesis in Tomato.

    PubMed

    Thagun, Chonprakun; Imanishi, Shunsuke; Kudo, Toru; Nakabayashi, Ryo; Ohyama, Kiyoshi; Mori, Tetsuya; Kawamoto, Koichi; Nakamura, Yukino; Katayama, Minami; Nonaka, Satoko; Matsukura, Chiaki; Yano, Kentaro; Ezura, Hiroshi; Saito, Kazuki; Hashimoto, Takashi; Shoji, Tsubasa

    2016-05-01

    Steroidal glycoalkaloids (SGAs) are cholesterol-derived specialized metabolites produced in species of the Solanaceae. Here, we report that a group of jasmonate-responsive transcription factors of the ETHYLENE RESPONSE FACTOR (ERF) family (JREs) are close homologs of alkaloid regulators in Cathranthus roseus and tobacco, and regulate production of SGAs in tomato. In transgenic tomato, overexpression and dominant suppression of JRE genes caused drastic changes in SGA accumulation and in the expression of genes for metabolic enzymes involved in the multistep pathway leading to SGA biosynthesis, including the upstream mevalonate pathway. Transactivation and DNA-protein binding assays demonstrate that JRE4 activates the transcription of SGA biosynthetic genes by binding to GCC box-like elements in their promoters. These JRE-binding elements occur at significantly higher frequencies in proximal promoter regions of the genes regulated by JRE genes, supporting the conclusion that JREs mediate transcriptional co-ordination of a series of metabolic genes involved in SGA biosynthesis. PMID:27084593

  2. Conversion of Exogenous Cholesterol into Glycoalkaloids in Potato Shoots, Using Two Methods for Sterol Solubilisation

    PubMed Central

    Petersson, Erik V.; Nahar, Nurun; Dahlin, Paul; Broberg, Anders; Tröger, Rikard; Dutta, Paresh C.; Jonsson, Lisbeth; Sitbon, Folke

    2013-01-01

    Steroidal glycoalkaloids (SGA) are toxic secondary metabolites naturally occurring in the potato, as well as in certain other Solanaceous plant species, such as tomato, eggplant and pepper. To investigate the steroidal origin of SGA biosynthesis, cut potato shoots were fed cholesterol labelled with deuterium (D) in the sterol ring structure (D5- or D6-labelled), or side chain (D7-labelled), and analysed after three or five weeks. The labelled cholesterol and presence of D-labelled SGA were analysed by GC-MS and LC-MS/MS, respectively. When feeding D-labelled cholesterol solubilised in Tween-80, labelled cholesterol in free form became present in both leaves and stems, although the major part was recovered as steryl esters. Minor amounts of D-labelled SGA (α-solanine and α-chaconine) were identified in cholesterol-treated shoots, but not in blank controls, or in shoots fed D6-27-hydroxycholesterol. Solubilising the labelled cholesterol in methyl-β-cyclodextrin instead of Tween-80 increased the levels of labelled SGA up to 100-fold, and about 1 mole% of the labelled cholesterol was recovered as labelled SGA in potato leaves. Both side chain and ring structure D labels were retained in SGA, showing that the entire cholesterol molecule is converted to SGA. However, feeding side chain D7-labelled cholesterol resulted in D5-labelled SGA, indicating that two hydrogen atoms were released during formation of the SGA nitrogen-containing ring system. Feeding with D7-sitosterol did not produce any labelled SGA, indicating that cholesterol is a specific SGA precursor. In conclusion, we have demonstrated a superior performance of methyl-β-cyclodextrin for delivery of cholesterol in plant tissue feeding experiments, and given firm evidence for cholesterol as a specific sterol precursor of SGA in potato. PMID:24349406

  3. Glycoalkaloids of wild and cultivated Solanum: effects on specialist and generalist insect herbivores.

    PubMed

    Altesor, Paula; García, Álvaro; Font, Elizabeth; Rodríguez-Haralambides, Alejandra; Vilaró, Francisco; Oesterheld, Martín; Soler, Roxina; González, Andrés

    2014-06-01

    Plant domestication by selective breeding may reduce plant chemical defense in favor of growth. However, few studies have simultaneously studied the defensive chemistry of cultivated plants and their wild congeners in connection to herbivore susceptibility. We compared the constitutive glycoalkaloids (GAs) of cultivated potato, Solanum tuberosum, and a wild congener, S. commersonii, by liquid chromatography coupled to mass spectrometry. We also determined the major herbivores present on the two species in field plots, and tested their preference for the plants and their isolated GAs in two-choice bioassays. Solanum commersonii had a different GA profile and higher concentrations than S. tuberosum. In the field, S. tuberosum was mostly attacked by the generalist aphids Myzus persicae and Macrosiphum euphorbiae, and by the specialist flea beetle Epitrix argentinensis. In contrast, the most common herbivore on S. commersonii was the specialist sawfly Tequus sp. Defoliation levels were higher on the wild species, probably due to the chewing feeding behavior of Tequus sp. As seen in the field, M. persicae and E. argentinensis preferred leaf disks of the cultivated plant, while Tequus sp. preferred those of the wild one. Congruently, GAs from S. commersonii were avoided by M. persicae and preferred by Tequus sp. The potato aphid performed well on both species and was not deterred by S. commersonii GAs. These observations suggest that different GA profiles explain the feeding preferences of the different herbivores, and that domestication has altered the defensive capacity of S. tuberosum. However, the wild relative is still subject to severe defoliation by a specialist herbivore that may cue on the GAs. PMID:24863489

  4. In Vivo Assessment of Genotoxic, Antigenotoxic and Anticarcinogenic Activities of Solanum lycocarpum Fruits Glycoalkaloidic Extract

    PubMed Central

    Munari, Carla Carolina; de Oliveira, Pollyanna Francielli; Leandro, Luis Fernando; Pimenta, Leandra Mara; Ferreira, Natália Helen; de Carvalho da Costa, Juliana; Bastos, Jairo Kenupp; Tavares, Denise Crispim

    2014-01-01

    The fruits of Solanum lycocarpum, known as wolf-fruit, are used in folk medicine, and because of that we have evaluated both the genotoxic potential of its glycoalkaloidic extract (SL) and its influence on the genotoxicity induced by methyl methanesulfonate. Furthermore, the potential blocking effect of SL intake in the initial stage of colon carcinogenesis in Wistar rats was investigated in a short-term (4-week) bioassay using aberrant crypt foci (ACF) as biomarker. The genotoxic potential was evaluated using the Swiss mice peripheral blood micronucleus test. The animals were treated with different doses of SL (15, 30 and 60 mg/kg b.w.) for 14 days, and the peripheral blood samples were collected at 48 h, 7 days and 14 days after starting the treatment. For antigenotoxicity assessment, MMS was administered on the 14th day, and after 24 h the harvesting of bone marrow and liver cells was performed, for the micronucleus and comet assays, respectively. In the ACF assay, male Wistar rats were given four subcutaneous injections of the carcinogen 1,2-dimethylhydrazine (DMH, 40 mg/kg b.w.), twice a week, during two weeks to induce ACF. The treatment with SL (15, 30 and 60 mg/kg b.w.) was given for four weeks during and after carcinogen treatment to investigate the potential beneficial effects of SL on DMH-induced ACF. The results demonstrated that SL was not genotoxic in the mouse micronucleus test. In animals treated with SL and MMS, the frequencies of micronucleus and extensions of DNA damage were significantly reduced in comparison with the animals receiving only MMS. Regarding the ACF assay, SL significantly reduced the frequency of ACF induced by DMH. PMID:25405606

  5. Phenolic and Glycoalkaloid Levels of S. Jamesii Accessions and their Anti-Proliferative Effect on Human Prostate and Colon Cancer Cells In Vitro

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Some tuber-bearing wild potato species are higher in antioxidant activity (AOA), phenolics (TP) and glycoalkaloids (TGA >200 mg/kg) than the potato of commerce. Hence, use of wild species as parental material in breeding for high AOA and TP might result in progenies with high TGA, if the traits are ...

  6. Impact of light-exposure on the metabolite balance of transgenic potato tubers with modified glycoalkaloid biosynthesis.

    PubMed

    Shepherd, Louise Vida Traill; Hackett, Christine Anne; Alexander, Colin James; McNicol, James William; Sungurtas, Julia Anne; McRae, Diane; McCue, Kent Frank; Belknap, William Richardson; Davies, Howard Vivian

    2016-06-01

    Metabolite profiling (liquid chromatography-mass spectrometry (LC-MS) and gas chromatography (GC-MS)) was used to assess the impact of light on the composition of transgenic potato (Solanum tuberosum L. cv. Desirée) with reduced glycoalkaloid content via the down-regulation of the SGT1 gene. Transgenic tubers exhibited an almost complete knock-out of α-solanine production and light had little impact on its accumulation. Levels of α-chaconine increased significantly in the peel of both the control and transgenic lines when exposed to light, particularly in the transgenic line. Major differences in metabolite profiles existed between outer and inner tuber tissues, and between light and dark-treated tubers. Many of the light-induced changes are explicable in terms of pathways known to be affected by stress responses. The impact of transgenesis on profiles was much less than that of tissue type or light and most differences were explicable in terms of the modification to the glycoalkaloid pathway. PMID:26830588

  7. GLYCOALKALOID METABOLISM1 Is Required for Steroidal Alkaloid Glycosylation and Prevention of Phytotoxicity in Tomato[W

    PubMed Central

    Itkin, Maxim; Rogachev, Ilana; Alkan, Noam; Rosenberg, Tally; Malitsky, Sergey; Masini, Laura; Meir, Sagit; Iijima, Yoko; Aoki, Koh; de Vos, Ric; Prusky, Dov; Burdman, Saul; Beekwilder, Jules; Aharoni, Asaph

    2011-01-01

    Steroidal alkaloids (SAs) are triterpene-derived specialized metabolites found in members of the Solanaceae family that provide plants with a chemical barrier against a broad range of pathogens. Their biosynthesis involves the action of glycosyltransferases to form steroidal glycoalkaloids (SGAs). To elucidate the metabolism of SGAs in the Solanaceae family, we examined the tomato (Solanum lycopersicum) GLYCOALKALOID METABOLISM1 (GAME1) gene. Our findings imply that GAME1 is a galactosyltransferase, largely performing glycosylation of the aglycone tomatidine, resulting in SGA production in green tissues. Downregulation of GAME1 resulted in an almost 50% reduction in α-tomatine levels (the major SGA in tomato) and a large increase in its precursors (i.e., tomatidenol and tomatidine). Surprisingly, GAME1-silenced plants displayed growth retardation and severe morphological phenotypes that we suggest occur as a result of altered membrane sterol levels caused by the accumulation of the aglycone tomatidine. Together, these findings highlight the role of GAME1 in the glycosylation of SAs and in reducing the toxicity of SA metabolites to the plant cell. PMID:22180624

  8. Overview of the Rocky Mountain Arsenal ecological risk characterization

    SciTech Connect

    Applehans, F.; Jones, M.; Osborn, S.; Tate, D.J.; Cothern, K.A.; Pavlou, S.; Toll, J.E.; Armstrong, J.P.

    1994-12-31

    The Rocky Mountain Arsenal (RMA) Endangerment Assessment was performed to characterize potential threats to human health and the environment from contaminants released as a result of historical operations and past waste disposal practices at RMA. This paper presents an overview of the Ecological Risk Characterization (ERC), one component of the RMA Endangerment Assessment. Because of the magnitude of the ERC and high public profile of RMA, the RMA ecological risk assessment reflects all aspects of SETAC`s meeting theme, Ecological Risk: Science, Policy, Law, and Perception. The conceptual framework for the ERC is described, major technical and practical issues encountered in conducting the ERC are recounted, and key insights and recommendations for future ecological risk assessments are discussed.

  9. Glycoalkaloids (α-chaconine and α-solanine) contents of selected Pakistani potato cultivars and their dietary intake assessment.

    PubMed

    Aziz, Abdul; Randhawa, Muhammad Atif; Butt, Masood Sadiq; Asghar, Ali; Yasin, Muhammad; Shibamoto, Takayuki

    2012-03-01

    Glycoalkaloids (α-solanine and α-chaconine) are naturally occurring toxic compounds in potato tuber (Solanum tuberosum L.) that cause acute intoxication in humans after their consumption. Present research was conducted to evaluate α-chaconine, α-solanine, and total glycoalkaloids (TGAs) contents in the peel and flesh portions by high-performance liquid chromatography method in selected Pakistani potato cultivars. The α-solanine content varies 45.98 ± 1.63 to 2742.60 ± 92.97 mg/100 g of dry weight (DW) in peel and from 4.01 ± 0.14 to 2466.56 ± 87.21 mg/100 g of DW in flesh. Similarly, α-chaconine content varied from 4.42 ± 0.16 to 6818.40 ± 211.07 mg/100 g of DW in potato peel and from 3.94 ± 0.14 to 475.33 ± 16.81 mg/100 g DW in flesh portion. The TGA concentration varied from 177.20 ± 6.26 to 5449.90 ± 192.68 mg/100 g of DW in peel and from 3.08 ± 0.11 to 14.69 ± 0.52 mg/100 g of DW in flesh portion of all the potato cultivars tested. All the potato cultivars contained lower concentration of TGA than the limits recommended as safe, except 2 cultivars, that is FD8-3 (2539.18 ± 89.77 mg/100 g of DW) and Cardinal (506.16 ± 17.90 mg/kg). The dietary intake assessment of potato cultivars revealed that Cardinal, FD 35-36, FD 8-3, and FD 3-9 contained higher amount of TGA in whole potato, although FD 8-3 only possessed higher content of TGA (154.93 ± 7.75) in its flesh portion rendering it unfit for human consumption. Practical Application:  This paper was based on the research conducted on toxic compounds present in all possible potato cultivars in Pakistan. Actually, we quantify the toxic compounds (glycoalkaloids) of potato cultivars through HPLC and their dietary assessment. This paper revealed safety assessment and their application in food industries especially potato processing. PMID:22329893

  10. Developing Hydrogeological Site Characterization Strategies based on Human Health Risk

    NASA Astrophysics Data System (ADS)

    de Barros, F.; Rubin, Y.; Maxwell, R. M.

    2013-12-01

    In order to provide better sustainable groundwater quality management and minimize the impact of contamination in humans, improved understanding and quantification of the interaction between hydrogeological models, geological site information and human health are needed. Considering the joint influence of these components in the overall human health risk assessment and the corresponding sources of uncertainty aid decision makers to better allocate resources in data acquisition campaigns. This is important to (1) achieve remediation goals in a cost-effective manner, (2) protect human health and (3) keep water supplies clean in order to keep with quality standards. Such task is challenging since a full characterization of the subsurface is unfeasible due to financial and technological constraints. In addition, human exposure and physiological response to contamination are subject to uncertainty and variability. Normally, sampling strategies are developed with the goal of reducing uncertainty, but less often they are developed in the context of their impacts on the overall system uncertainty. Therefore, quantifying the impact from each of these components (hydrogeological, behavioral and physiological) in final human health risk prediction can provide guidance for decision makers to best allocate resources towards minimal prediction uncertainty. In this presentation, a multi-component human health risk-based framework is presented which allows decision makers to set priorities through an information entropy-based visualization tool. Results highlight the role of characteristic length-scales characterizing flow and transport in determining data needs within an integrated hydrogeological-health framework. Conditions where uncertainty reduction in human health risk predictions may benefit from better understanding of the health component, as opposed to a more detailed hydrogeological characterization, are also discussed. Finally, results illustrate how different dose

  11. Risk Informed Margins Management as part of Risk Informed Safety Margin Characterization

    SciTech Connect

    Curtis Smith

    2014-06-01

    The ability to better characterize and quantify safety margin is important to improved decision making about Light Water Reactor (LWR) design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margin management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. In addition, as research and development in the LWR Sustainability (LWRS) Program and other collaborative efforts yield new data, sensors, and improved scientific understanding of physical processes that govern the aging and degradation of plant SSCs needs and opportunities to better optimize plant safety and performance will become known. To support decision making related to economics, readability, and safety, the Risk Informed Safety Margin Characterization (RISMC) Pathway provides methods and tools that enable mitigation options known as risk informed margins management (RIMM) strategies.

  12. Approaches to characterizing human health risks of exposure to fibers.

    PubMed Central

    Vu, V T; Lai, D Y

    1997-01-01

    Naturally occurring and man-made (synthetic) fibers of respirable sizes are substances that have been identified by the U.S. Environmental Protection Agency (U.S. EPA) as priority substances for risk reduction and pollution prevention under the Toxic Substances Control Act (TSCA). The health concern for respirable fibers is based on the link of occupational asbestos exposure and environmental erionite fiber exposure to the development of chronic respiratory diseases, including interstitial lung fibrosis, lung cancer, and mesothelioma in humans. There is also considerable laboratory evidence indicating that a variety of fibers of varying physical and chemical characteristics can elicit fibrogenic and carcinogenic effects in animals under certain exposure conditions. This paper discusses key scientific issues and major default assumptions and uncertainties pertaining to the risk assessment of inhaled fibers. This is followed by a description of the types of assessment performed by the U.S. EPA to support risk management actions of new fibers and existing fibers under TSCA. The scope and depth of these risk assessments, however, vary greatly depending on whether the substance under review is an existing or a new fiber, the purpose of the assessment, the availability of data, time, and resources, and the intended nature of regulatory action. In general, these risk assessments are of considerable uncertainty because health hazard and human exposure information is often incomplete for most fibers. Furthermore, how fibers cause diseases and what specific determinants are critical to fiber-induced toxicity and carcinogenicity are still not completely understood. Further research to improve our knowledge base in fiber toxicology and additional toxicity and exposure data gathering are needed to more accurately characterize the health risks of inhaled fibers. PMID:9400747

  13. Quantitative risk assessment of Listeria monocytogenes in French cold-smoked salmon: II. Risk characterization.

    PubMed

    Pouillot, Régis; Goulet, Véronique; Delignette-Muller, Marie Laure; Mahé, Aurélie; Cornu, Marie

    2009-06-01

    A model for the assessment of exposure to Listeria monocytogenes from cold-smoked salmon consumption in France was presented in the first of this pair of articles (Pouillot et al., 2007, Risk Analysis, 27:683-700). In the present study, the exposure model output was combined with an internationally accepted hazard characterization model, adapted to the French situation, to assess the risk of invasive listeriosis from cold-smoked salmon consumption in France in a second-order Monte Carlo simulation framework. The annual number of cases of invasive listeriosis due to cold-smoked salmon consumption in France is estimated to be 307, with a very large credible interval ([10; 12,453]), reflecting data uncertainty. This uncertainty is mainly associated with the dose-response model. Despite the significant uncertainty associated with the predictions, this model provides a scientific base for risk managers and food business operators to manage the risk linked to cold-smoked salmon contaminated with L. monocytogenes. Under the modeling assumptions, risk would be efficiently reduced through a decrease in the prevalence of L. monocytogenes or better control of the last steps of the cold chain (shorter and/or colder storage during the consumer step), whereas reduction of the initial contamination levels of the contaminated products and improvement in the first steps of the cold chain do not seem to be promising strategies. An attempt to apply the recent risk-based concept of FSO (food safety objective) on this example underlines the ambiguity in practical implementation of the risk management metrics and the need for further elaboration on these concepts. PMID:19220799

  14. Risk-Informed Safety Margin Characterization Methods Development Work

    SciTech Connect

    Smith, Curtis L; Ma, Zhegang; Tom Riley; Mandelli, Diego; Nielsen, Joseph W; Alfonsi, Andrea; Rabiti, Cristian

    2014-09-01

    This report summarizes the research activity developed during the Fiscal year 2014 within the Risk Informed Safety Margin and Characterization (RISMC) pathway within the Light Water Reactor Sustainability (LWRS) campaign. This research activity is complementary to the one presented in the INL/EXT-??? report which shows advances Probabilistic Risk Assessment Analysis using RAVEN and RELAP-7 in conjunction to novel flooding simulation tools. Here we present several analyses that prove the values of the RISMC approach in order to assess risk associated to nuclear power plants (NPPs). We focus on simulation based PRA which, in contrast to classical PRA, heavily employs system simulator codes. Firstly we compare, these two types of analyses, classical and RISMC, for a Boiling water reactor (BWR) station black out (SBO) initiating event. Secondly we present an extended BWR SBO analysis using RAVEN and RELAP-5 which address the comments and suggestions received about he original analysis presented in INL/EXT-???. This time we focus more on the stochastic analysis such probability of core damage and on the determination of the most risk-relevant factors. We also show some preliminary results regarding the comparison between RELAP5-3D and the new code RELAP-7 for a simplified Pressurized Water Reactors system. Lastly we present some conceptual ideas regarding the possibility to extended the RISMC capabilities from an off-line tool (i.e., as PRA analysis tool) to an online-tool. In this new configuration, RISMC capabilities can be used to assist and inform reactor operator during real accident scenarios.

  15. Characterization of Evidence for Human System Risk Assessment

    NASA Technical Reports Server (NTRS)

    Steinberg, S. L.; Van Baalen, M.; Rossi, M.; Riccio, G.; Romero, E.; Francisco, D.

    2016-01-01

    Understanding the kinds of evidence available and using the best evidence to answer a question is critical to evidenced-based decision-making, and it requires synthesis of evidence from a variety of sources. Categorization of human system risks in spaceflight, in particular, focuses on how well the integration and interpretation of all available evidence informs the risk statement that describes the relationship between spaceflight hazards and an outcome of interest. A mature understanding and categorization of these risks requires: 1) sufficient characterization of risk, 2) sufficient knowledge to determine an acceptable level of risk (i.e., a standard), 3) development of mitigations to meet the acceptable level of risk, and 4) identification of factors affecting generalizability of the evidence to different design reference missions. In the medical research community, evidence is often ranked by increasing confidence in findings gleaned from observational and experimental research (e.g., "levels of evidence"). However, an approach based solely on aspects of experimental design is problematic in assessing human system risks for spaceflight. For spaceflight, the unique challenges and opportunities include: (1) The independent variables in most evidence are the hazards of spaceflight, such as space radiation or low gravity, which cannot be entirely duplicated in terrestrial (Earth-based) analogs, (2) Evidence is drawn from multiple sources including medical and mission operations, Lifetime Surveillance of Astronaut Health (LSAH), spaceflight research (LSDA), and relevant environmental & terrestrial databases, (3) Risk metrics based primarily on LSAH data are typically derived from available prevalence or incidence data, which may limit rigorous interpretation, (4) The timeframe for obtaining adequate spaceflight sample size (n) is very long, given the small population, (5) Randomized controlled trials are unattainable in spaceflight, (6) Collection of personal and

  16. Human health risk characterization of petroleum coke calcining facility emissions.

    PubMed

    Singh, Davinderjit; Johnson, Giffe T; Harbison, Raymond D

    2015-12-01

    Calcining processes including handling and storage of raw petroleum coke may result in Particulate Matter (PM) and gaseous emissions. Concerns have been raised over the potential association between particulate and aerosol pollution and adverse respiratory health effects including decrements in lung function. This risk characterization evaluated the exposure concentrations of ambient air pollutants including PM10 and gaseous pollutants from a petroleum coke calciner facility. The ambient air pollutant levels were collected through monitors installed at multiple locations in the vicinity of the facility. The measured and modeled particulate levels in ambient air from the calciner facility were compared to standards protective of public health. The results indicated that exposure levels were, on occasions at sites farther from the facility, higher than the public health limit of 150 μg/m(3) 24-h average for PM10. However, the carbon fraction demonstrated that the contribution from the calciner facility was de minimis. Exposure levels of the modeled SO2, CO, NOx and PM10 concentrations were also below public health air quality standards. These results demonstrate that emissions from calcining processes involving petroleum coke, at facilities that are well controlled, are below regulatory standards and are not expected to produce a public health risk. PMID:26520182

  17. Exploring public databases to characterize urban flood risks in Amsterdam

    NASA Astrophysics Data System (ADS)

    Gaitan, Santiago; ten Veldhuis, Marie-claire; van de Giesen, Nick

    2015-04-01

    Cities worldwide are challenged by increasing urban flood risks. Precise and realistic measures are required to decide upon investment to reduce their impacts. Obvious flooding factors affecting flood risk include sewer systems performance and urban topography. However, currently implemented sewer and topographic models do not provide realistic predictions of local flooding occurrence during heavy rain events. Assessing other factors such as spatially distributed rainfall and socioeconomic characteristics may help to explain probability and impacts of urban flooding. Several public databases were analyzed: complaints about flooding made by citizens, rainfall depths (15 min and 100 Ha spatio-temporal resolution), grids describing number of inhabitants, income, and housing price (1Ha and 25Ha resolution); and buildings age. Data analysis was done using Python and GIS programming, and included spatial indexing of data, cluster analysis, and multivariate regression on the complaints. Complaints were used as a proxy to characterize flooding impacts. The cluster analysis, run for all the variables except the complaints, grouped part of the grid-cells of central Amsterdam into a highly differentiated group, covering 10% of the analyzed area, and accounting for 25% of registered complaints. The configuration of the analyzed variables in central Amsterdam coincides with a high complaint count. Remaining complaints were evenly dispersed along other groups. An adjusted R2 of 0.38 in the multivariate regression suggests that explaining power can improve if additional variables are considered. While rainfall intensity explained 4% of the incidence of complaints, population density and building age significantly explained around 20% each. Data mining of public databases proved to be a valuable tool to identify factors explaining variability in occurrence of urban pluvial flooding, though additional variables must be considered to fully explain flood risk variability.

  18. Comparative assessment of absolute cardiovascular disease risk characterization from non-laboratory-based risk assessment in South African populations

    PubMed Central

    2013-01-01

    Background All rigorous primary cardiovascular disease (CVD) prevention guidelines recommend absolute CVD risk scores to identify high- and low-risk patients, but laboratory testing can be impractical in low- and middle-income countries. The purpose of this study was to compare the ranking performance of a simple, non-laboratory-based risk score to laboratory-based scores in various South African populations. Methods We calculated and compared 10-year CVD (or coronary heart disease (CHD)) risk for 14,772 adults from thirteen cross-sectional South African populations (data collected from 1987 to 2009). Risk characterization performance for the non-laboratory-based score was assessed by comparing rankings of risk with six laboratory-based scores (three versions of Framingham risk, SCORE for high- and low-risk countries, and CUORE) using Spearman rank correlation and percent of population equivalently characterized as ‘high’ or ‘low’ risk. Total 10-year non-laboratory-based risk of CVD death was also calculated for a representative cross-section from the 1998 South African Demographic Health Survey (DHS, n = 9,379) to estimate the national burden of CVD mortality risk. Results Spearman correlation coefficients for the non-laboratory-based score with the laboratory-based scores ranged from 0.88 to 0.986. Using conventional thresholds for CVD risk (10% to 20% 10-year CVD risk), 90% to 92% of men and 94% to 97% of women were equivalently characterized as ‘high’ or ‘low’ risk using the non-laboratory-based and Framingham (2008) CVD risk score. These results were robust across the six risk scores evaluated and the thirteen cross-sectional datasets, with few exceptions (lower agreement between the non-laboratory-based and Framingham (1991) CHD risk scores). Approximately 18% of adults in the DHS population were characterized as ‘high CVD risk’ (10-year CVD death risk >20%) using the non-laboratory-based score. Conclusions We found a high level of

  19. Assessing Risks to Populations at Superfund and Rcra Sites: Characterizing Effects on Populations (Final)

    EPA Science Inventory

    The Ecological Risk Assessment Support Center (ERASC) announced the release of the final document titled, Assessing Risks to Populations at Superfund and RCRA Sites: Characterizing Effects on Populations.

  20. Characterizing and Reaching High-Risk Drinkers Using Audience Segmentation

    PubMed Central

    Moss, Howard B.; Kirby, Susan D.; Donodeo, Fred

    2010-01-01

    Background Market or audience segmentation is widely used in social marketing efforts to help planners identify segments of a population to target for tailored program interventions. Market-based segments are typically defined by behaviors, attitudes, knowledge, opinions, or lifestyles. They are more helpful to health communication and marketing planning than epidemiologically-defined groups because market-based segments are similar in respect to how they behave or might react to marketing and communication efforts. However, market segmentation has rarely been used in alcohol research. As an illustration of its utility, we employed commercial data that describes the sociodemographic characteristics of high-risk drinkers as an audience segment; where they tend to live, lifestyles, interests, consumer behaviors, alcohol consumption behaviors, other health-related behaviors, and cultural values. Such information can be extremely valuable in targeting and planning public health campaigns, targeted mailings, prevention interventions and research efforts. Methods We describe the results of a segmentation analysis of those individuals who self-report consuming five or more drinks per drinking episode at least twice in the last 30-days. The study used the proprietary PRIZM™ audience segmentation database merged with Center for Disease Control and Prevention's (CDC) Behavioral Risk Factor Surveillance System (BRFSS) database. The top ten of the 66 PRIZM™ audience segments for this risky drinking pattern are described. For five of these segments we provide additional in-depth details about consumer behavior and the estimates of the market areas where these risky drinkers reside. Results The top ten audience segments (PRIZM clusters) most likely to engage in high-risk drinking are described. The cluster with the highest concentration of binge drinking behavior is referred to as the “Cyber Millenials.” This cluster is characterized as “the nation's tech-savvy singles

  1. Sequence diversity in coding regions of candidate genes in the glycoalkaloid biosynthetic pathway of wild potato species.

    PubMed

    Manrique-Carpintero, Norma C; Tokuhisa, James G; Ginzberg, Idit; Holliday, Jason A; Veilleux, Richard E

    2013-09-01

    Natural variation in five candidate genes of the steroidal glycoalkaloid (SGA) metabolic pathway and whole-genome single nucleotide polymorphism (SNP) genotyping were studied in six wild [Solanum chacoense (chc 80-1), S. commersonii, S. demissum, S. sparsipilum, S. spegazzinii, S. stoloniferum] and cultivated S. tuberosum Group Phureja (phu DH) potato species with contrasting levels of SGAs. Amplicons were sequenced for five candidate genes: 3-hydroxy-3-methylglutaryl coenzyme A reductase 1 and 2 (HMG1, HMG2) and 2.3-squalene epoxidase (SQE) of primary metabolism, and solanidine galactosyltransferase (SGT1), and glucosyltransferase (SGT2) of secondary metabolism. SNPs (n = 337) producing 354 variations were detected within 3.7 kb of sequenced DNA. More polymorphisms were found in introns than exons and in genes of secondary compared to primary metabolism. Although no significant deviation from neutrality was found, dN/dS ratios < 1 and negative values of Tajima's D test suggested purifying selection and genetic hitchhiking in the gene fragments. In addition, patterns of dN/dS ratios across the SGA pathway suggested constraint by natural selection. Comparison of nucleotide diversity estimates and dN/dS ratios showed stronger selective constraints for genes of primary rather than secondary metabolism. SNPs (n = 24) with an exclusive genotype for either phu DH (low SGA) or chc 80-1 (high SGA) were identified for HMG2, SQE, SGT1 and SGT2. The SolCAP 8303 Illumina Potato SNP chip genotyping revealed eight informative SNPs on six pseudochromosomes, with homozygous and heterozygous genotypes that discriminated high, intermediate and low levels of SGA accumulation. These results can be used to evaluate SGA accumulation in segregating or association mapping populations. PMID:23853090

  2. Sequence Diversity in Coding Regions of Candidate Genes in the Glycoalkaloid Biosynthetic Pathway of Wild Potato Species

    PubMed Central

    Manrique-Carpintero, Norma C.; Tokuhisa, James G.; Ginzberg, Idit; Holliday, Jason A.; Veilleux, Richard E.

    2013-01-01

    Natural variation in five candidate genes of the steroidal glycoalkaloid (SGA) metabolic pathway and whole-genome single nucleotide polymorphism (SNP) genotyping were studied in six wild [Solanum chacoense (chc 80-1), S. commersonii, S. demissum, S. sparsipilum, S. spegazzinii, S. stoloniferum] and cultivated S. tuberosum Group Phureja (phu DH) potato species with contrasting levels of SGAs. Amplicons were sequenced for five candidate genes: 3-hydroxy-3-methylglutaryl coenzyme A reductase 1 and 2 (HMG1, HMG2) and 2.3-squalene epoxidase (SQE) of primary metabolism, and solanidine galactosyltransferase (SGT1), and glucosyltransferase (SGT2) of secondary metabolism. SNPs (n = 337) producing 354 variations were detected within 3.7 kb of sequenced DNA. More polymorphisms were found in introns than exons and in genes of secondary compared to primary metabolism. Although no significant deviation from neutrality was found, dN/dS ratios < 1 and negative values of Tajima’s D test suggested purifying selection and genetic hitchhiking in the gene fragments. In addition, patterns of dN/dS ratios across the SGA pathway suggested constraint by natural selection. Comparison of nucleotide diversity estimates and dN/dS ratios showed stronger selective constraints for genes of primary rather than secondary metabolism. SNPs (n = 24) with an exclusive genotype for either phu DH (low SGA) or chc 80-1 (high SGA) were identified for HMG2, SQE, SGT1 and SGT2. The SolCAP 8303 Illumina Potato SNP chip genotyping revealed eight informative SNPs on six pseudochromosomes, with homozygous and heterozygous genotypes that discriminated high, intermediate and low levels of SGA accumulation. These results can be used to evaluate SGA accumulation in segregating or association mapping populations. PMID:23853090

  3. Characterizing risk factors for pediatric lamp oil product exposures

    PubMed Central

    SHEIKH, S.; CHANG, A.; KIESZAK, S.; LAW, R.; BENNETT, H. K. W.; ERNST, E.; BOND, G. R.; SPILLER, H. A.; SCHURZ-ROGERS, H.; CHU, A.; BRONSTEIN, A. C.; SCHIER, J. G.

    2015-01-01

    Poisonings from lamp oil ingestion continue to occur worldwide among the pediatric population despite preventive measures such as restricted sale of colored and scented lamp oils. This suggests that optimal prevention practices for unintentional pediatric exposures to lamp oil have yet to be identified and/or properly implemented. Objective To characterize demographic, health data, and potential risk factors associated with reported exposures to lamp oil by callers to poison centers (PCs) in the US and discuss their public health implications. Study design . This was a two part study in which the first part included characterizing all exposures to a lamp oil product reported to the National Poison Data System (NPDS) with regard to demographics, exposure, health, and outcome data from 1/1/2000 to 12/31/2010. Regional penetrance was calculated using NPDS data by grouping states into four regions and dividing the number of exposure calls by pediatric population per region (from the 2000 US census). Temporal analyses were performed on NPDS data by comparing number of exposures by season and around the July 4th holiday. Poisson regression was used to model the count of exposures for these analyses. In the second part of this project, in order to identify risk factors we conducted a telephone-based survey to the parents of children from five PCs in five different states. The 10 most recent lamp oil product exposure calls for each poison center were systematically selected for inclusion. Calls in which a parent or guardian witnessed a pediatric lamp oil product ingestion were eligible for inclusion. Data on demographics, exposure information, behavioral traits, and health were collected. A descriptive analysis was performed and Fisher’s exact test was used to evaluate associations between variables. All analyses were conducted using SAS v9.3. Results Among NPDS data, 2 years was the most common patient age reported and states in the Midwestern region had the highest

  4. LC-MS analysis of solanidane glycoalkaloid diversity among four wild potato species and three cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Among the small molecules found in potato tubers are some that are phytonutrients or plant defense compounds. The extent of variation of these small molecules among different potato genotypes is not well characterized. LCMS analysis of tuber extracts from seven potato genotypes showed that one larg...

  5. LC-MS analysis of glycoalkaloid diversity among seven potato genotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Secondary metabolites in potato tubers include both phytonutrients and plant defense compounds. The extent of variation in these small molecules among different potato genotypes is not well characterized. LC-MS analysis of tuber extracts from seven potato genotypes showed that one large source of sm...

  6. Ecological risk characterization based on exposure to contaminants through the Rocky Mountain Arsenal aquatic food chains

    SciTech Connect

    Toll, J.E.; Cothern, K.A.; Pavlou, S.; Tate, D.J.; Armstrong, J.P.

    1994-12-31

    This paper describes ecological risk characterization methods and results for characterizing potential risk from exposure to bioaccumulative contaminants of concern (aldrin, dieldrin, endrin, DDT, DDE, and mercury) through the lake food chains at Rocky Mountain Arsenal (RMA). Aquatic risks were estimated for the bald eagle, great blue heron, shorebird, and water bird using a prey-tissue-concentration-based food web model. Methods for estimating missing tissue concentration data were developed on a case-by-case basis and will be described. A sediment-based food web model was also considered and the reasons for its rejection will be described. Generalizable insights from the aquatic ecological risk characterization will be discussed.

  7. Characterizing declines in pediatric antidepressant use after new risk disclosures

    PubMed Central

    Frank, Richard G.; Martin, Andres; Barry, Colleen L.

    2010-01-01

    Steep declines in pediatric antidepressant use were documented following the 2004 release of new safety information associating antidepressants with a risk of suicidality. We examine whether declines in pediatric antidepressant use were steeper among individuals with certain clinical or family characteristics. We find that declines in antidepressant use were associated with new (as compared to ongoing) treatment episodes. Also, although rates of antidepressant use were higher among children of college educated parents prior to risk disclosures, these children were more likely to forgo antidepressant medication than children of less educated parents after risk disclosures. We find that both children with and without psychiatric impairment experienced declines in antidepressant medication use following the risk warnings, although the decline occurred more quickly in the latter group. Our findings highlight the need for additional data to assess the effects of risk disclosures on treatment patterns and health outcomes. PMID:20675349

  8. Characterizing public health and microbial risks due to water contaminants

    EPA Science Inventory

    This research track evaluates risks associated with the occurrence of waterborne disease in the population. A clear understanding of the health burden associated with exposure to contaminated drinking water is critical to developing regulations that are protective of public healt...

  9. WORKSHOP REPORT ON CHARACTERIZING ECOLOGICAL RISK AT THE WATERSHED SCALE

    EPA Science Inventory

    As ecological risk assessment evolves, it is moving beyond a focus on single species toward addressing multiple species and their interactions, and from assessing effects of simple chemical toxicity to the cumulative impacts of multiple interacting chemical, physical, and biologi...

  10. A Risk Management Framework to Characterize Black Swan Risks: A Case Study of Lightning Effects on Insensitive High Explosives

    NASA Astrophysics Data System (ADS)

    Sanders, Gary A.

    Effective and efficient risk management processes include the use of high fidelity modeling and simulation during the concept exploration phase as part of the technology and risk assessment activities, with testing and evaluation tasks occurring in later design development phases. However, some safety requirements and design architectures may be dominated by the low probability/high consequence "Black Swan" vulnerabilities that require very early testing to characterize and efficiently mitigate. Failure to address these unique risks has led to catastrophic systems failures including the space shuttle Challenger, Deepwater Horizon, Fukushima nuclear reactor, and Katrina dike failures. Discovering and addressing these risks later in the design and development process can be very costly or even lead to project cancellation. This paper examines the need for risk management process adoption of early hazard phenomenology testing to inform the technical risk assessment, requirements definition and conceptual design. A case study of the lightning design vulnerability of the insensitive high explosives being used in construction, mining, demolition, and defense industries will be presented to examine the impact of this vulnerability testing during the concept exploration phase of the design effort. While these insensitive high explosives are far less sensitive to accidental initiation by fire, impact, friction or even electrical stimuli, their full range of sensitivities have not been characterized and ensuring safe engineering design and operations during events such as lightning storms requires vulnerability testing during the risk assessment phase.

  11. Quantitative, Qualitative and Geospatial Methods to Characterize HIV Risk Environments

    PubMed Central

    Conners, Erin E.; West, Brooke S.; Roth, Alexis M.; Meckel-Parker, Kristen G.; Kwan, Mei-Po; Magis-Rodriguez, Carlos; Staines-Orozco, Hugo; Clapp, John D.; Brouwer, Kimberly C.

    2016-01-01

    Increasingly, ‘place’, including physical and geographical characteristics as well as social meanings, is recognized as an important factor driving individual and community health risks. This is especially true among marginalized populations in low and middle income countries (LMIC), whose environments may also be more difficult to study using traditional methods. In the NIH-funded longitudinal study Mapa de Salud, we employed a novel approach to exploring the risk environment of female sex workers (FSWs) in two Mexico/U.S. border cities, Tijuana and Ciudad Juárez. In this paper we describe the development, implementation, and feasibility of a mix of quantitative and qualitative tools used to capture the HIV risk environments of FSWs in an LMIC setting. The methods were: 1) Participatory mapping; 2) Quantitative interviews; 3) Sex work venue field observation; 4) Time-location-activity diaries; 5) In-depth interviews about daily activity spaces. We found that the mixed-methodology outlined was both feasible to implement and acceptable to participants. These methods can generate geospatial data to assess the role of the environment on drug and sexual risk behaviors among high risk populations. Additionally, the adaptation of existing methods for marginalized populations in resource constrained contexts provides new opportunities for informing public health interventions. PMID:27191846

  12. Quantitative, Qualitative and Geospatial Methods to Characterize HIV Risk Environments.

    PubMed

    Conners, Erin E; West, Brooke S; Roth, Alexis M; Meckel-Parker, Kristen G; Kwan, Mei-Po; Magis-Rodriguez, Carlos; Staines-Orozco, Hugo; Clapp, John D; Brouwer, Kimberly C

    2016-01-01

    Increasingly, 'place', including physical and geographical characteristics as well as social meanings, is recognized as an important factor driving individual and community health risks. This is especially true among marginalized populations in low and middle income countries (LMIC), whose environments may also be more difficult to study using traditional methods. In the NIH-funded longitudinal study Mapa de Salud, we employed a novel approach to exploring the risk environment of female sex workers (FSWs) in two Mexico/U.S. border cities, Tijuana and Ciudad Juárez. In this paper we describe the development, implementation, and feasibility of a mix of quantitative and qualitative tools used to capture the HIV risk environments of FSWs in an LMIC setting. The methods were: 1) Participatory mapping; 2) Quantitative interviews; 3) Sex work venue field observation; 4) Time-location-activity diaries; 5) In-depth interviews about daily activity spaces. We found that the mixed-methodology outlined was both feasible to implement and acceptable to participants. These methods can generate geospatial data to assess the role of the environment on drug and sexual risk behaviors among high risk populations. Additionally, the adaptation of existing methods for marginalized populations in resource constrained contexts provides new opportunities for informing public health interventions. PMID:27191846

  13. EVALUATION OF RISKS AND WASTE CHARACTERIZATION REQUIREMENTS FOR THE TRANSURANIC WASTE EMPLACED IN WIPP DURING 1999

    SciTech Connect

    Channell, J.K.; Walker, B.A.

    2000-05-01

    Specifically this report: 1. Compares requirements of the WAP that are pertinent from a technical viewpoint with the WIPP pre-Permit waste characterization program, 2. Presents the results of a risk analysis of the currently emplaced wastes. Expected and bounding risks from routine operations and possible accidents are evaluated; and 3. Provides conclusions and recommendations.

  14. FASTER SCIENCE FOR BETTER DECISIONS: CHARACTERIZING ENVIRONMENTAL CONTAMINANT RISK FROM HIGH THROUGHPUT DATA

    EPA Science Inventory

    Tens of thousands of chemicals and other man-made contaminants exist in our environment, but only a fraction of these have been characterized for their potential risk to humans and there is widespread interest in closing this data gap in order to better manage contaminant risk. C...

  15. IMPROVED RISK CHARACTERIZATION METHODS FOR DEVELOPING AQUATIC LIFE CRITERIA FOR NON-BIOACCUMULATIVE TOXICANTS

    EPA Science Inventory

    This project will use existing and developing information to evaluate and demonstrate procedures for more fully characterizing risks of non-bioaccumulative toxicants to aquatic organisms, and for incorporating these risks into aquatic life criteria. These efforts will address a v...

  16. Profile sampling to characterize particulate lead risks in potable water.

    PubMed

    Clark, Brandi; Masters, Sheldon; Edwards, Marc

    2014-06-17

    Traditional lead (Pb) profiling, or collecting sequential liters of water that flow from a consumer tap after a stagnation event, has recently received widespread use in understanding sources of Pb in drinking water and risks to consumer health, but has limitations in quantifying particulate Pb risks. A new profiling protocol was developed in which a series of traditional profiles are collected from the same tap at escalating flow rates. The results revealed marked differences in risks of Pb exposure from one consumer home to another as a function of flow rate, with homes grouped into four risk categories with differing flushing requirements and public education to protect consumers. On average, Pb concentrations detected in water at high flow without stagnation were at least three to four times higher than in first draw samples collected at low flow with stagnation, demonstrating a new "worst case" lead release scenario, contrary to the original regulatory assumption that stagnant, first draw samples contain the highest lead concentrations. Testing also revealed that in some cases water samples with visible particulates had much higher Pb than samples without visible particulates, and tests of different sample handling protocols confirmed that some EPA-allowed methods would not quantify as much as 99.9% of the Pb actually present (avg. 27% of Pb not quantified). PMID:24865841

  17. AN APPROACH FOR CHARACTERIZING TROPOSPHERIC OZONE RISK TO FOREST

    EPA Science Inventory

    The risk tropospheric ozone poses to forests in the United States is dependent on the variation in ozone exposure across the distribution of the forests in question and the various environmental and climate factors predominant in the region. All these factors have a spatial natur...

  18. Characterization and evaluation of uncertainty in probabilistic risk analysis

    SciTech Connect

    Parry, G.W.; Winter, P.W.

    1981-01-01

    The sources of uncertainty in probabilistic risk analysis are discussed, using the event and fault-tree methodology as an example. The role of statistics in quantifying these uncertainties is investigated. A class of uncertainties is identified which are, at present, unquantifiable using either classical or Bayesian statistics. it is argued that Bayesian statistics is the more appropriate vehicle for the probabilistic analysis of rare events, and a short review is given with some discussion on the representation of ignorance.

  19. Characterization and Risk Factor Analysis for Reoperation After Microendoscopic Diskectomy.

    PubMed

    Hong, Xin; Liu, Lei; Bao, Junping; Shi, Rui; Fan, Yudong; Wu, Xiaotao

    2015-06-01

    A population-based database of 1263 consecutive patients who underwent microendoscopic diskectomy for single-level lumbar disk herniation between 2005 and 2010 was retrospectively analyzed to identify causes and characteristics of reoperation and associated risk factors. A total of 952 patients were eligible. Of these, 58 had revision spinal surgery. Causes and clinical parameters were retrospectively assessed, and possible risk factors were evaluated by multivariate logistic regression analysis. In total, 76 disk herniations were excised with revision diskectomy, with or without interbody fusion. The overall mean interval between primary surgery and revision surgery was 39.05 months (range, 2-95 months). Cumulative overall reoperation rates gradually increased from 1.56% at 1 year to 8.17% after nearly 10 years. Reoperated patients were older and had a higher level of lumbar degeneration, with severe Modic changes (type 1, 17.2%; type 2, 34.5%), vs patients without reoperation (type 1, 1.5%; type 2, 30.6%). In addition, patients with reoperation had a higher rate of obvious adjacent disk degeneration (81.1%). Logistic regression analysis showed that adjacent segment degeneration and Pfirrmann grading for disk degeneration were significant risk factors for reoperation after primary microendoscopic diskectomy (odds ratios, 2.448 and 1.510, respectively). The current study reported a relatively low incidence of reoperation after primary microendoscopic diskectomy. Adjacent segment degeneration and Pfirrmann grading for disk degeneration were identified as risk factors for reoperation after microendoscopic diskectomy to treat lumbar disk herniation. Treatment options for patients with these factors at the first visit should be carefully evaluated. PMID:26091222

  20. Risk characterization of detergent surfactants in the Netherlands

    SciTech Connect

    Feijtel, T.; Plassche, E. van de

    1995-12-31

    The Dutch Soap Association (NVZ) and the Dutch Environmental Ministry (VROM) developed in 1991 an aquatic hazard priority list of all detergent ingredients. The agreed priority list consisted of linear alkylbenzene sulfonate (LAS), alcohol ethoxylates (AE), alcohol ethoxylated sulfates (AES), and soap. A stepwise or tiered risk assessment approach was adopted as the recommended approach to evaluate the risk of these surfactants. This implies that depending on the risk (or PEC/PNEC) ratio, the sequential test program or assessment would proceed further, to ensure adequate protection of the ecosystem. The agreed calculation scheme for the aquatic compartment is based on the comparison of the 90th percentile of Predicted Environmental Concentrations (PEC) in the Netherlands -- at 1,000 meter below the sewage outfall -- to the Predicted No Effect Concentration (PNEC) for ecosystems. The 90th percentile surfactant concentrations at 1,000 meter below the sewage outfall can be calculated using information or data on (1) release, (2) in-sewer removal, (3) treatment efficiency, (4) dilution and (5) instream-removal and/or measured in representative sites in The Netherlands. In addition, all toxicological data was critically reviewed by company experts and experts of RIVM and VROM to present a rationale for a sound database for the derivation of a Predicted No Effect Concentration (PNEC). It was concluded that the risk of LAS, AE and AES and soap for the aquatic environment is low. Also taking the estimated uncertainty into account, the predicted environmental concentrations are always considerably lower that the predicted no effect concentrations.

  1. Treatment of Passive Component Reliability in Risk-Informed Safety Margin Characterization FY 2010 Report

    SciTech Connect

    Robert W Youngblood

    2010-09-01

    The Risk-Informed Safety Margin Characterization (RISMC) pathway is a set of activities defined under the U.S. Department of Energy (DOE) Light Water Reactor Sustainability Program. The overarching objective of RISMC is to support plant life-extension decision-making by providing a state-of-knowledge characterization of safety margins in key systems, structures, and components (SSCs). A technical challenge at the core of this effort is to establish the conceptual and technical feasibility of analyzing safety margin in a risk-informed way, which, unlike conventionally defined deterministic margin analysis, is founded on probabilistic characterizations of SSC performance.

  2. Proliferation Risk Characterization Model Prototype Model - User and Programmer Guidelines

    SciTech Connect

    Dukelow, J.S.; Whitford, D.

    1998-12-01

    A model for the estimation of the risk of diversion of weapons-capable materials was developed. It represents both the threat of diversion and site vulnerability as a product of a small number of variables (two to eight), each of which can take on a small number (two to four) of qualitatively defined (but quantitatively implemented) values. The values of the overall threat and vulnerability variables are then converted to threat and vulnerability categories. The threat and vulnerability categories are used to define the likelihood of diversion, also defined categorically. The evaluator supplies an estimate of the consequences of a diversion, defined categorically, but with the categories based on the IAEA Attractiveness levels. Likelihood and Consequences categories are used to define the Risk, also defined categorically. The threat, vulnerability, and consequences input provided by the evaluator contains a representation of his/her uncertainty in each variable assignment which is propagated all the way through to the calculation of the Risk categories. [Appendix G available on diskette only.

  3. Children's exposure to mercury-contaminated soils: exposure assessment and risk characterization.

    PubMed

    Guney, Mert; Welfringer, Bruno; de Repentigny, Carl; Zagury, Gerald J

    2013-08-01

    Exposure to mercury (Hg)-contaminated soils may pose a health risk to children by way of oral, dermal, and inhalatory pathways. However, risk characterization studies, including contaminant bioaccessibility with child-specific exposure parameters and scenarios, are lacking. The objectives of this study were (1) to assess children's Hg exposure using characterization and oral bioaccessibility data from Hg-contaminated soils characterized in previous studies (n = 8); and (2) to characterize probabilistic risk in terms of hazard index (HI) considering ingestion, dermal, and inhalation pathways. Total Hg concentrations in soils ranged from 2.61 to 1.15 × 10(4) mg kg(-1). For moderately contaminated soils (S1-S5: Hg ≤ 12.15 mg kg(-1)), low oral bioaccessibility values (1.5-7.5 %) lead to HI < 1 in all scenarios. However, exposure to highly contaminated soils (S6-S8) may pose serious risks to children under normal exposure (HI 0.89-66.5) and soil-pica behaviour scenarios (HI up to 131). All three pathways significantly contributed to the risk. Using total Hg concentrations in calculations (assuming 100 % bioavailability) instead of considering Hg bioavailability leads to risk overestimation. Further research on oral, inhalatory, and dermal bioavailability of Hg, as well as child play behaviour, is recommended to obtain more accurate risk estimates. PMID:23546335

  4. Reference manual for toxicity and exposure assessment and risk characterization. CERCLA Baseline Risk Assessment

    SciTech Connect

    1995-03-01

    The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, 1980) (CERCLA or Superfund) was enacted to provide a program for identifying and responding to releases of hazardous substances into the environment. The Superfund Amendments and Reauthorization Act (SARA, 1986) was enacted to strengthen CERCLA by requiring that site clean-ups be permanent, and that they use treatments that significantly reduce the volume, toxicity, or mobility of hazardous pollutants. The National Oil and Hazardous Substances Pollution Contingency Plan (NCP) (USEPA, 1985; USEPA, 1990) implements the CERCLA statute, presenting a process for (1) identifying and prioritizing sites requiring remediation and (2) assessing the extent of remedial action required at each site. The process includes performing two studies: a Remedial Investigation (RI) to evaluate the nature, extent, and expected consequences of site contamination, and a Feasibility Study (FS) to select an appropriate remedial alternative adequate to reduce such risks to acceptable levels. An integral part of the RI is the evaluation of human health risks posed by hazardous substance releases. This risk evaluation serves a number of purposes within the overall context of the RI/FS process, the most essential of which is to provide an understanding of ``baseline`` risks posed by a given site. Baseline risks are those risks that would exist if no remediation or institutional controls are applied at a site. This document was written to (1) guide risk assessors through the process of interpreting EPA BRA policy and (2) help risk assessors to discuss EPA policy with regulators, decision makers, and stakeholders as it relates to conditions at a particular DOE site.

  5. Environmental auditing: An approach for characterizing tropospheric ozone risk to forests

    SciTech Connect

    Hogsett, W.E.; Weber, J.E.; Tingey, D.; Herstrom, A.; Lee, E.H.; Laurence, J.A.

    1997-01-01

    The risk tropospheric ozone poses to forests in the United States dependents on the variation in ozone exposure across the forests and the various environmental and climate factors predominant in the region. All these factors have a spatial nature; an approach to characterization of ozone risk is presented that places ozone exposure-response functions for species as seedlings and model-simulated tree and stand responses in a spatial context using a geographical information systems (GIS). The GIS is used to aggregate factors considered important in a risk characterization: (1) estimated ozone exposures over forested regions, (2) measures of ozone effects on species` and stand growth, and (3) spatially distributed environmental, genetic, and exposure influences on species` response to ozone. The GIS-based risk characterization provides an estimation the extent and magnitude of the potential ozone impact on forests. A preliminary risk characterization demonstrating this considered only the eastern United States and only the limited empirical data quantifying the effect of ozone exposures on forest tree species as seedlings. The area-weighted response of the annual seedling biomass loss formed the basis for a sensitivity ranking: sensitive-aspen and black cherry (14%-33% biomass loss over 50% of their distribution); moderately sensitive-tulip popular, loblolly pine, eastern white pine, and sugar maple (5%-13% biomass loss); insensitive-Virginia pine and red maple (0%-1% loss). Future GIS-based risk characterizations will include process-based model simulations of the three- to 5-year growth response of individual species as large trees. The interactive nature of GIS provides a tool to explore consequences of the range of climate conditions across a species` distribution, forest management practices, changing ozone precursors, regulatory control strategies, and other factors influencing the spatial distribution of ozone over time. 43 refs., 11 figs., 3 tabs.

  6. Landscape characterization of peridomestic risk for Lyme disease using satellite imagery

    NASA Technical Reports Server (NTRS)

    Dister, S. W.; Fish, D.; Bros, S. M.; Frank, D. H.; Wood, B. L.

    1997-01-01

    Remotely sensed characterizations of landscape composition were evaluated for Lyme disease exposure risk on 337 residential properties in two communities of suburban Westchester County, New York. Properties were categorized as no, low, or high risk based on seasonally adjusted densities of Ixodes scapularis nymphs, determined by drag sampling during June and July 1990. Spectral indices based on Landsat Thematic Mapper data provided relative measures of vegetation structure and moisture (wetness), as well as vegetation abundance (greenness). A geographic information system (GIS) was used to spatially quantify and relate the remotely sensed landscape variables to risk category. A comparison of the two communities showed that Chappaqua, which had more high-risk properties (P < 0.001), was significantly greener and wetter than Armonk (P < 0.001). Furthermore, within Chappaqua, high-risk properties were significantly greener and wetter than lower-risk properties in this community (P < 0.01). The high-risk properties appeared to contain a greater proportion of broadleaf trees, while lower-risk properties were interpreted as having a greater proportion of nonvegetative cover and/or open lawn. The ability to distinguish these fine scale differences among communities and individual properties illustrates the efficiency of a remote sensing/GIS-based approach for identifying peridomestic risk of Lyme disease over large geographic areas.

  7. Development of a liquid chromatography-tandem mass spectrometric method for the simultaneous determination of tropane alkaloids and glycoalkaloids in crops.

    PubMed

    Jandrić, Z; Rathor, M N; Švarc-Gajić, J; Maestroni, B M; Sasanya, J J; Djurica, R; Cannavan, A

    2011-09-01

    A new, rapid and sensitive multiresidue method is reported for the simultaneous determination of tropane alkaloids (tropine, atropine, scopolamine, homatropine, anisodamine) and glycoalkaloids (α-solanine, α-chaconine) in grains and seeds (wheat, rye, maize, soybean, linseed). Dispersive solid phase extraction (DSPE) was performed with 0.5% formic acid in acetonitrile/water and a mixture of magnesium sulphate, sodium chloride and sodium citrate. For a fast and effective clean-up procedure for oily matrices such as soybean and linseed, matrix solid phase dispersion (MSPD) C(18) material was used to remove co-extracted non-polar components. No clean-up was necessary for less oily matrices following extraction. The analytes were separated by isocratic HPLC on a Chirobiotic V column and detected using a triple quadrupole mass spectrometer with electrospray ionization (ESI). All analytes were monitored in the positive ion mode. The method performance is presented in terms of linearity in the range 5-80 ng/g (r(2)=0.998), specifity, selectivity, accuracy (recoveries from 61-111%), precision (CV<5%) and ruggedness. The limits of quantitation (LOQ) were in the range 2.2-4.9 ng/g. PMID:21838651

  8. Sterol side chain reductase 2 is a key enzyme in the biosynthesis of cholesterol, the common precursor of toxic steroidal glycoalkaloids in potato.

    PubMed

    Sawai, Satoru; Ohyama, Kiyoshi; Yasumoto, Shuhei; Seki, Hikaru; Sakuma, Tetsushi; Yamamoto, Takashi; Takebayashi, Yumiko; Kojima, Mikiko; Sakakibara, Hitoshi; Aoki, Toshio; Muranaka, Toshiya; Saito, Kazuki; Umemoto, Naoyuki

    2014-09-01

    Potatoes (Solanum tuberosum) contain α-solanine and α-chaconine, two well-known toxic steroidal glycoalkaloids (SGAs). Sprouts and green tubers accumulate especially high levels of SGAs. Although SGAs were proposed to be biosynthesized from cholesterol, the biosynthetic pathway for plant cholesterol is poorly understood. Here, we identify sterol side chain reductase 2 (SSR2) from potato as a key enzyme in the biosynthesis of cholesterol and related SGAs. Using in vitro enzyme activity assays, we determined that potato SSR2 (St SSR2) reduces desmosterol and cycloartenol to cholesterol and cycloartanol, respectively. These reduction steps are branch points in the biosynthetic pathways between C-24 alkylsterols and cholesterol in potato. Similar enzymatic results were also obtained from tomato SSR2. St SSR2-silenced potatoes or St SSR2-disrupted potato generated by targeted genome editing had significantly lower levels of cholesterol and SGAs without affecting plant growth. Our results suggest that St SSR2 is a promising target gene for breeding potatoes with low SGA levels. PMID:25217510

  9. Application of single-stage Orbitrap mass spectrometry and differential analysis software to nontargeted analysis of contaminants in dog food: detection, identification, and quantification of glycoalkaloids.

    PubMed

    Lohne, Jack J; Turnipseed, Sherri B; Andersen, Wendy C; Storey, Joseph; Madson, Mark R

    2015-05-20

    The objective of this study was to perform a preliminary investigation of the nontargeted search and quantitative capabilities of a single-stage Exactive High-Resolution Mass Spectrometer (HRMS). To do this, the instrument and its associated software performed a non-targeted search for deleterious substances in a dog food sample suspected of causing gastrointestinal problems in dogs. A single-stage Orbitrap/high-performance liquid chromatography method and differential expression analysis software (Sieve) was used to detect and identify, and subsequently quantify, nontargeted compounds occurring only in the suspect dog food sample. When combined with an online database (ChemSpider), a preliminary identification of one of the nontargeted compounds was determined to be potato glycoalkaloids. The diagnostic product ion ratios and quantitative data accuracy generated by the single-stage Orbitrap MS were shown to be similar to results obtained using a triple quadrupole LC-MS/MS. Additionally, the ability of the single-stage Orbitrap instrument to provide precursor and product ion accurate masses and isotope patterns was also investigated. PMID:25912523

  10. Sterol Side Chain Reductase 2 Is a Key Enzyme in the Biosynthesis of Cholesterol, the Common Precursor of Toxic Steroidal Glycoalkaloids in Potato[W][OPEN

    PubMed Central

    Sawai, Satoru; Ohyama, Kiyoshi; Yasumoto, Shuhei; Seki, Hikaru; Sakuma, Tetsushi; Yamamoto, Takashi; Takebayashi, Yumiko; Kojima, Mikiko; Sakakibara, Hitoshi; Aoki, Toshio; Muranaka, Toshiya; Saito, Kazuki; Umemoto, Naoyuki

    2014-01-01

    Potatoes (Solanum tuberosum) contain α-solanine and α-chaconine, two well-known toxic steroidal glycoalkaloids (SGAs). Sprouts and green tubers accumulate especially high levels of SGAs. Although SGAs were proposed to be biosynthesized from cholesterol, the biosynthetic pathway for plant cholesterol is poorly understood. Here, we identify sterol side chain reductase 2 (SSR2) from potato as a key enzyme in the biosynthesis of cholesterol and related SGAs. Using in vitro enzyme activity assays, we determined that potato SSR2 (St SSR2) reduces desmosterol and cycloartenol to cholesterol and cycloartanol, respectively. These reduction steps are branch points in the biosynthetic pathways between C-24 alkylsterols and cholesterol in potato. Similar enzymatic results were also obtained from tomato SSR2. St SSR2-silenced potatoes or St SSR2-disrupted potato generated by targeted genome editing had significantly lower levels of cholesterol and SGAs without affecting plant growth. Our results suggest that St SSR2 is a promising target gene for breeding potatoes with low SGA levels. PMID:25217510

  11. Complex mixtures of air pollutants: characterizing the cancer risk of polycyclic organic matter.

    PubMed Central

    Lewtas, J

    1993-01-01

    Complex mixtures of polycyclic organic matter (POM) are used to illustrate the scientific problems and issues associated with characterizing the comparative risk of related complex mixtures. The complexity of mixtures in which the active components are not well characterized present special challenges, which include identifying the critical components of mixtures, their sources, and the appropriate biomarker(s) of exposure and dose; developing the appropriate experimental models for dose-response assessment; species extrapolation; and developing a scientific basis for predicting from one mixture to another. Strategies for addressing these issues include bioassay-directed chemical characterization of bioactive components of complex mixtures, apportionment methods to determine the source of biological activity and risk, DNA adduct methods to determine tissue exposure and target dose of mixtures, and comparative approaches to determining the relative similarity, potency, and risk of complex mixtures. Epidemiological data are available for humans exposed to POM from coke ovens, coal roofing tar, coal smoke, aluminum smelters, and cigarette smoke. These emissions are characterized and compared to POM from automotive emissions (diesel and gasoline), woodstove emissions, residential oil furnace emissions, and ambient air particles. The tumor potency and estimated cancer risks for these POM mixtures ranges over nearly three orders of magnitude. PMID:8354169

  12. Complex mixtures of air pollutants: Characterizing the cancer risk of polycyclic organic matter

    SciTech Connect

    Lewtas, J. )

    1993-04-01

    Complex mixtures of polycyclic organic matter (POM) are used to illustrate the scientific problems and issues associated with characterizing the comparative risk of related complex mixtures. The complexity of mixtures in which the active components are not well characterized present special challenges, which include identifying the critical components of mixtures, their sources, and the appropriate biomark(s) of exposure and dose; developing the appropriate experimental models for dose-response assessment; species extrapolation; and developing a scientific basis for predicting from one mixture to another. Strategies for addressing these issues include bioassay-directed chemical characterization of bioactive components of complex mixtures, apportionment methods to determine the source of biological activity and risk, DNA adduct methods to determine tissue exposure and target dose of mixtures, and comparative approaches to determining the relative similarity, potency, and risk of complex mixtures. Epidemiological data are available for humans exposed to POM from coke ovens, coal roofing tar, coal smoke, aluminum smelters, and cigarette smoke. These emissions are characterized and compared to POM from automotive emissions (diesel and gasoline), woodstove emissions, residential oil furnace emissions, and ambient air particles. The tumor potency and estimated cancer risks for these POM mixtures ranges over nearly three orders of magnitude. 41 refs., 8 figs.

  13. Characterizing Uncertainty in Epidemiological Studies for use in Human Health Risk Assessment

    EPA Science Inventory

    Characterization of scientific uncertainty can provide risk assessments with a level of confidence regarding decisions, whichallows for evaluation of the degree that uncertainty plays in the analysis of consequences of specific policies.To the best of our knowledge, there are no ...

  14. Impact of ground motion characterization on conservatism and variability in seismic risk estimates

    SciTech Connect

    Sewell, R.T.; Toro, G.R.; McGuire, R.K.

    1996-07-01

    This study evaluates the impact, on estimates of seismic risk and its uncertainty, of alternative methods in treatment and characterization of earthquake ground motions. The objective of this study is to delineate specific procedures and characterizations that may lead to less biased and more precise seismic risk results. This report focuses on sources of conservatism and variability in risk that may be introduced through the analytical processes and ground-motion descriptions which are commonly implemented at the interface of seismic hazard and fragility assessments. In particular, implication of the common practice of using a single, composite spectral shape to characterize motions of different magnitudes is investigated. Also, the impact of parameterization of ground motion on fragility and hazard assessments is shown. Examination of these results demonstrates the following. (1) There exists significant conservatism in the review spectra (usually, spectra characteristic of western U.S. earthquakes) that have been used in conducting past seismic risk assessments and seismic margin assessments for eastern U.S. nuclear power plants. (2) There is a strong dependence of seismic fragility on earthquake magnitude when PGA is used as the ground-motion characterization. When, however, magnitude-dependent spectra are anchored to a common measure of elastic spectral acceleration averaged over the appropriate frequency range, seismic fragility shows no important nor consistent dependence on either magnitude or strong-motion duration. Use of inelastic spectral acceleration (at the proper frequency) as the ground spectrum anchor demonstrates a very similar result. This study concludes that a single, composite-magnitude spectrum can generally be used to characterize ground motion for fragility assessment without introducing significant bias or uncertainty in seismic risk estimates.

  15. Conclusions of the Capstone depleted uranium aerosol characterization and risk assessment study.

    PubMed

    Parkhurst, Mary Ann; Guilmette, Raymond A

    2009-03-01

    The rationale for the Capstone Depleted Uranium (DU) Aerosol Characterization and Risk Assessment Study and its results and applications have been examined in the previous 13 articles of this special issue. This paper summarizes the study's results and discusses its successes and lessons learned. The robust data from the Capstone DU Aerosol Study have provided a sound basis for assessing the inhalation exposure to DU aerosols and the dose and risk to personnel in combat vehicles at the time of perforation and to those entering immediately after perforation. The Human Health Risk Assessment provided a technically sound process for evaluating chemical and radiological doses and risks from DU aerosol exposure using well-accepted biokinetic and dosimetric models innovatively applied. An independent review of the study process and results is summarized, and recommendations for possible avenues of future study are provided by the authors and by other major reviews of DU health hazards. PMID:19204494

  16. Defining, characterizing, and establishing "safe enough" risk thresholds for human space flight

    NASA Astrophysics Data System (ADS)

    Ocampo, Robert Paul

    No spacecraft will ever be perfectly safe. Consequently, engineers must strive to design, develop, and operate spacecraft that are safe enough. This thesis presents a conceptual framework for defining and characterizing "safe" and distinguishing "safe enough" from "not safe enough." Space Shuttle and Soyuz safety records are presented in the context of this framework, and compared to the safety records of various modes of transportation (automotive, rail, boating, general aviation, commercial aviation) and adventure sport activities (skydiving, mountaineering, SCUBA diving). From these comparisons, a heuristic method for predicting space flight risk is derived. This method, which is built upon the inverse correlation between risk and usage, can coarsely predict risk in the absence of detailed spacecraft data. Based on these predictions, spacecraft risk can either be accepted as "safe enough" or rejected as "not safe enough."

  17. Development, Application, and Implementation of RAMCAP to Characterize Nuclear Power Plant Risk From Terrorism

    SciTech Connect

    Gaertner, John P.; Teagarden, Grant A.

    2006-07-01

    In response to increased interest in risk-informed decision making regarding terrorism, EPRI and ERIN Engineering were selected by U.S. DHS and ASME to develop and demonstrate the RAMCAP method for nuclear power plant (NPP) risk assessment. The objective is to characterize plant-specific NPP risk for risk management opportunities and to provide consistent information for DHS decision making. This paper is an update of this project presented at the American Nuclear Society (ANS) International Topical Meeting on Probabilistic Safety Analysis (PSA05) in September, 2005. The method uses a characterization of risk as a function of Consequence, Vulnerability, and Threat. For each site, worst case scenarios are developed for each of sixteen benchmark threats. Nuclear RAMCAP hypothesizes that the intent of the perpetrator is to cause offsite radiological consequences. Specific targets are the reactor core, the spent fuel pool, and nuclear spent fuel in a dry storage facility (ISFSI). Results for each scenario are presented as conditional risk for financial loss, early fatalities and early injuries. Expected consequences for each scenario are quantified, while vulnerability is estimated on a relative likelihood scale. Insights for other societal risks are provided. Although threat frequencies are not provided, target attractiveness and threat deterrence are estimated. To assure efficiency, completeness, and consistency; results are documented using standard RAMCAP Evaluator software. Trial applications were successfully performed at four plant sites. Implementation at all other U.S. commercial sites is underway, supported by the Nuclear Sector Coordinating Council (NSCC). Insights from RAMCAP results at 23 U.S. plants completed to date have been compiled and presented to the NSCC. Results are site-specific. Physical security barriers, an armed security force, preparedness for design-basis threats, rugged design against natural hazards, multiple barriers between fuel and

  18. Pre-site characterization risk analysis for commercial-scale carbon sequestration.

    PubMed

    Dai, Zhenxue; Stauffer, Philip H; Carey, J William; Middleton, Richard S; Lu, Zhiming; Jacobs, John F; Hnottavange-Telleen, Ken; Spangler, Lee H

    2014-04-01

    This study develops a probability framework to evaluate subsurface risks associated with commercial-scale carbon sequestration in the Kevin Dome, Montana. Limited knowledge of the spatial distribution of physical attributes of the storage reservoir and the confining rocks in the area requires using regional data to estimate project risks during the pre-site characterization analysis. A set of integrated Monte Carlo simulations are used to assess four risk proxies: the CO2 injectivity, area of review (AoR), migration rate into confining rocks, and a monitoring strategy prior to detailed site characterization. Results show a reasonable likelihood of reaching the project goal of injecting 1 Mt in 4 years with a single injection well (>58%), increasing to >70% if the project is allowed to run for 5 years. The mean radius of the AoR, based on a 0.1 MPa pressure change, is around 4.8 km. No leakage of CO2 through the confining units is seen in any simulations. The computed CO2 detection probability suggests that the monitoring wells should be located at less than 1.2 km away from the injection well so that CO2 is likely to be detected within the time frame of the project. The scientific results of this study will be used to inform the detailed site characterization process and to provide more insight for understanding operational and technical risks before injecting CO2. PMID:24625081

  19. Terrestrial eco-risk -- Exposure assessment and risk characterization at Rocky Mountain Arsenal

    SciTech Connect

    Tate, D.J.; Cothern, K.A.; Jones, M.L.; Applehans, F. |; Armstrong, J.P.

    1994-12-31

    Terrestrial eco-risk was assessed at Rocky Mountain Arsenal using data from about 9,700 soil samples and 1,400 biota samples from 19 taxa. These databases reflect considerable spatial variability in historical uses of the 27-square mile site, in concentration of the 14 contaminants of concern (COCs) in soil, and in the distribution of soil borings and surficial soil samples, as well as spatial variability in tissue concentrations of samples that were collected from locations that were biased toward areas associated with high COC concentrations or thorough to be uncontaminated. This variability plus the considerable uncertainty in associating biota tissue concentrations with exposure soil concentrations resulted in extensive discussion and the development of an innovative and effective protocol for using interpolated soil concentrations to estimate tissue concentrations that were compared to toxicity reference values for tissue and dose concentrations. The broad outlines of the Endangerment Assessment Technical Subcommittee members` uncharted journey through literature surveys, parameter quantification, statistical nuances, exposure area soil concentration estimation, and development of a proportionality constant (e.g., a site-specific biomagnification factor) to link soil and tissue concentrations will be described and linked to a more detailed afternoon poster presentation.

  20. Using the Lorenz Curve to Characterize Risk Predictiveness and Etiologic Heterogeneity.

    PubMed

    Mauguen, Audrey; Begg, Colin B

    2016-07-01

    The Lorenz curve is a graphical tool that is used widely in econometrics. It represents the spread of a probability distribution, and its traditional use has been to characterize population distributions of wealth or income, or more specifically, inequalities in wealth or income. However, its utility in public health research has not been broadly established. The purpose of this article is to explain its special usefulness for characterizing the population distribution of disease risks, and in particular for identifying the precise disease burden that can be predicted to occur in segments of the population that are known to have especially high (or low) risks, a feature that is important for evaluating the yield of screening or other disease prevention initiatives. We demonstrate that, although the Lorenz curve represents the distribution of predicted risks in a population at risk for the disease, in fact it can be estimated from a case-control study conducted in the population without the need for information on absolute risks. We explore two different estimation strategies and compare their statistical properties using simulations. The Lorenz curve is a statistical tool that deserves wider use in public health research. PMID:27096256

  1. Characterization of Vascular Disease Risk in Postmenopausal Women and Its Association with Cognitive Performance

    PubMed Central

    Dowling, N. Maritza; Gleason, Carey E.; Manson, JoAnn E.; Hodis, Howard N.; Miller, Virginia M.; Brinton, Eliot A.; Neal-Perry, Genevieve; Santoro, M. Nanette; Cedars, Marcelle; Lobo, Rogerio; Merriam, George R.; Wharton, Whitney; Naftolin, Frederick; Taylor, Hugh; Harman, S. Mitchell; Asthana, Sanjay

    2013-01-01

    Objectives While global measures of cardiovascular (CV) risk are used to guide prevention and treatment decisions, these estimates fail to account for the considerable interindividual variability in pre-clinical risk status. This study investigated heterogeneity in CV risk factor profiles and its association with demographic, genetic, and cognitive variables. Methods A latent profile analysis was applied to data from 727 recently postmenopausal women enrolled in the Kronos Early Estrogen Prevention Study (KEEPS). Women were cognitively healthy, within three years of their last menstrual period, and free of current or past CV disease. Education level, apolipoprotein E ε4 allele (APOE4), ethnicity, and age were modeled as predictors of latent class membership. The association between class membership, characterizing CV risk profiles, and performance on five cognitive factors was examined. A supervised random forest algorithm with a 10-fold cross-validation estimator was used to test accuracy of CV risk classification. Results The best-fitting model generated two distinct phenotypic classes of CV risk 62% of women were “low-risk” and 38% “high-risk”. Women classified as low-risk outperformed high-risk women on language and mental flexibility tasks (p = 0.008) and a global measure of cognition (p = 0.029). Women with a college degree or above were more likely to be in the low-risk class (OR = 1.595, p = 0.044). Older age and a Hispanic ethnicity increased the probability of being at high-risk (OR = 1.140, p = 0.002; OR = 2.622, p = 0.012; respectively). The prevalence rate of APOE-ε4 was higher in the high-risk class compared with rates in the low-risk class. Conclusion Among recently menopausal women, significant heterogeneity in CV risk is associated with education level, age, ethnicity, and genetic indicators. The model-based latent classes were also associated with cognitive function. These differences may point to

  2. Induction of potato steroidal glycoalkaloid biosynthetic pathway by overexpression of cDNA encoding primary metabolism HMG-CoA reductase and squalene synthase.

    PubMed

    Ginzberg, Idit; Thippeswamy, Muddarangappa; Fogelman, Edna; Demirel, Ufuk; Mweetwa, Alice M; Tokuhisa, James; Veilleux, Richard E

    2012-06-01

    Potato steroidal glycoalkaloids (SGAs) are toxic secondary metabolites whose total content in tubers must be regulated. SGAs are biosynthesized by the sterol branch of the mevalonic acid/isoprenoid pathway. In a previous study, we showed a correlation between SGA levels and the abundance of transcript coding for HMG-CoA reductase 1 (HMG1) and squalene synthase 1 (SQS1) in potato tissues and potato genotypes varying in SGA content. Here, Solanum tuberosum cv. Desirée (low SGA producer) was transformed with a gene construct containing the coding region of either HMG1 or SQS1 of Solanum chacoense Bitt. clone 8380-1, a high SGA producer. SGA levels in transgenic HMG-plants were either greater than (in eight of 14 plants) or no different from untransformed controls, whereas only four of 12 SQS-transgenics had greater SGA levels than control, as determined by HPLC. Quantitative real-time PCR was used to estimate relative steady-state transcript levels of isoprenoid-, steroid-, and SGA-related genes in leaves of the transgenic plants compared to nontransgenic controls. HMG-transgenic plants exhibited increased transcript accumulation of SQS1, sterol C24-methyltransferase type1 (SMT1), and solanidine glycosyltransferase 2 (SGT2), whereas SQS-transgenic plants, had consistently lower transcript levels of HMG1 and variable SMT1 and SGT2 transcript abundance among different transgenics. HMG-transgenic plants exhibited changes in transcript accumulation for some sterol biosynthetic genes as well. Taken together, the data suggest coordinated regulation of isoprenoid metabolism and SGA secondary metabolism. PMID:22205426

  3. Potential considerations & concerns in the risk characterization for the interaction profiles of metals.

    PubMed

    Choudhury, H; Mudipalli, Anu

    2008-10-01

    The contaminants of concern for smelting and mining sites include arsenic (As), cadmium (Cd), lead (Pb) and zinc (Zn). Risk assessments for such sites need to consider whether toxicity values can be developed for this mixture, and if not, whether interactions among the individual components are significant and can be incorporated quantitatively into the assessment. No information is available for the risk characterization of the toxic interactions of AsCdPbZn mixtures. Studies of the AsCdPb and CdPbZn mixtures supported the assumption that a reasonable approximation to the toxicity of a mixture can be achieved by considering the binary submixtures. Data relevant to long-term simultaneous exposure to binary submixtures were not conclusive. For example, data from animal and human studies of Zn and Pb suggested that moderately elevated Zn intakes may slightly inhibit Pb absorption and haematological effects in children who have deficient or marginal Zn intakes, but were not adequate for adjusting absorption parameters in the Integrated Exposure Uptake Biokinetic (IEUBK) model for Pb. Thus the existing database calls for plausible approaches for risk characterization and considerations in the data usage for such characterization. This article is an attempt to identify such data gaps and the scientific considerations for such efforts. PMID:19106441

  4. Assessing Freshwater Ecosystem Service Risk over Ecological, Socioeconomic, and Cultural Gradients: Problem Space Characterization and Methodology

    NASA Astrophysics Data System (ADS)

    Harmon, T. C.; Villamizar, S. R.; Conde, D.; Rusak, J.; Reid, B.; Astorga, A.; Perillo, G. M.; Piccolo, M. C.; Zilio, M.; London, S.; Velez, M.; Hoyos, N.; Escobar, J.

    2014-12-01

    Freshwater ecosystems and the services they provide are under increasing anthropogenic pressure at local (e.g., irrigation diversions, wastewater discharge) and global scales (e.g., climate change, global trading). The impact depends on an ecosystem's sensitivity, which is determined by its geophysical and ecological settings, and the population and activities in its surrounding watershed. Given the importance of ecosystem services, it is critical that we improve our ability to identify and understand changes in aquatic ecosystems, and translate them to risk of service loss. Furthermore, to inspire changes in human behavior, it is equally critical that we learn to communicate risk, and pose risk mitigation strategies, in a manner acceptable to a broad spectrum of stakeholders. Quantifying the nature and timing of the risk is difficult because (1) we often fail to understand the connection between anthropogenic pressures and the timing and extent of ecosystem changes; and (2) the concept of risk is inherently coupled to human perception, which generally differs with cultural and socio-economic conditions. In this study, we endeavor to assess aquatic ecosystem risks across an international array of six study sites. The challenge is to construct a methodology capable of capturing the marked biogeographical, socioeconomic, and cultural differences among the sites, which include: (1) Muskoka River watershed in humid continental Ontario, Canada; (2) Lower San Joaquin River, an impounded snow-fed river in semi-arid Central California; (3) Ciénaga Grande de Santa Marta, a tropical coastal lagoon in Colombia; (4) Senguer River basin in the semi-arid part of Argentina; (5) Laguna de Rocha watershed in humid subtropical Uruguay; and (6) Palomas Lake complex in oceanic Chilean Patagonia. Results will include a characterization of the experimental gradient over the six sites, an overview of the risk assessment methodology, and preliminary findings for several of the sites.

  5. Characterization and solubility measurements of uranium-contaminated soils to support risk assessment

    SciTech Connect

    Elless, M.P.; Armstrong, A.Q.; Lee, S.Y.

    1997-05-01

    Remediation of uranium-contaminated soils is considered a high priority by the US Department of Energy because these soils, if left untreated, represent a hazard to the environment and human health. Because the risk to human health is a function of the solubility of uranium in the soils, the objectives of this work are to measure the uranium solubility of two contaminated soils, before and after remedial treatment, and determine the health risk associated with these soils. Two carbonate-rich, uranium-contaminated soils from the US Department of Energy Fernald Environmental Management Project facility near Cincinnati, Ohio, as well as two nearby background soils were characterized and their uranium solubility measured in a 75-d solubility experiment using acid rain, groundwater, lung serum, and stomach acid simulants. Results show that the soluble uranium levels of each soil by each simulant are greatly influenced by their contamination source term. Risk calculations and biokinetic modeling based on the solubility data show that the risks from the soil ingestion and groundwater ingestion pathways are the predominant contributors to the total carcinogenic risk, whereas the risk from the soil inhalation pathway is the smallest contributor to this risk. However, kidney toxicity was the greater health concern of the Fernald Environmental Management Project soils, primarily from undiluted ingestion of the groundwater solution following contact with the contaminated soils. Sensitivity analyses indicate that uranium solubility is a key parameter in defining kidney toxicity; therefore, without proper consideration of the solubility of radionuclides/metals in untreated and treated soils, important factors may be overlooked which may result in soil cleanup goals or limits which are not protective of human health and the environment.

  6. The Use of the Satellite Breakup Risk Assessment Model (SBRAM) to Characterize Collision Risk to Manned Spacecraft

    NASA Technical Reports Server (NTRS)

    Matney, Mark J.; Theall, Jeffrey R.; McKay, Gordon A. (Technical Monitor)

    1999-01-01

    NASA uses environment models such as ORDEM96 to characterize the long-term orbital debris collision hazard for spacecraft in LEO. Occasionally, however, there are breakups of satellites or rocket bodies that create enhanced collision hazard for a period of time. This enhanced collision hazard can pose increased risks to space operations - especially those involving manned missions where the tolerance for risk is very low. NASA has developed SBRAM to simulate the enhanced debris environment in the days and weeks that follow such a breakup. This simulation provides the kind of risk probabilities that can be used by mission planners to consider if changes are warranted for the mission. Announcements of breakups come to NASA from US Space Command as soon as they are identified. The pre-breakup orbit and time of breakup are used to determine the initial conditions of the explosion. SBRAM uses the latest explosion models developed at NASA to simulate a debris cloud for the breakup. The model uses a Monte Carlo technique to create a random debris cloud from the probability distributions in the breakup model. Each piece of debris randomly created in the cloud is propagated in a deterministic manner to include the effects of drag and other orbital perturbations. The detailed geometry of each simulated close approach to the target spacecraft is noted and logged and the collision probability is computed using an estimated probability density in down-range and cross-range positions of both the target spacecraft and debris object. The collision probability is computed from the overlap of these probability densities for each close-approach geometry and summed over all computed conjunctions. Cloud propagation runs over the desired time interval are then repeated until the scale of the collision risk can be estimated to a desired precision. This paper presents an overview of the SBRAM model and a number of examples, both real and hypothetical, to demonstrate its use. In addition

  7. CHARACTERIZATION OF ORGANIC EMISSIONS FROM HAZARDOUS WASTE INCINERATION PROCESSES UNDER THE NEW EPA DRAFT RISK BURN GUIDANCE: MEASUREMENT ISSUES

    EPA Science Inventory

    The paper discusses measurement issues relating to the characterization of organic emissions from hazardous waste incineration processes under EPA's new risk burn guidance. The recently published draft quidance recommends that hazardous waste combustion facilities complete a mass...

  8. Yucca Mountain transportation routes: Preliminary characterization and risk analysis; Volume 1, Research report

    SciTech Connect

    Souleyrette, R.R. II; Sathisan, S.K.; di Bartolo, R.

    1991-05-31

    In this study, rail and highway routes which may be used for shipments of high-level nuclear waste to a proposed repository at Yucca Mountain, Nevada are characterized. This characterization facilitates three types of impact analysis: comparative study, limited worst-case assessment, and more sophisticated probabilistic risk assessment techniques. Data for relative and absolute impact measures are provided to support comparisons of routes based on selected characteristics. A worst-case scenario assessment is included to determine potentially critical and most likely places for accidents or incidents to occur. The assessment facilitated by the data in this study is limited because impact measures are restricted to the identification of potential areas or persons affected. No attempt is made to quantify the magnitude of these impacts. Most likely locations for accidents to occur are determined relative to other locations within the scope of this study. Independent factors and historical trends used to identify these likely locations are only proxies for accident probability.

  9. Characterization of engineered TiO₂ nanomaterials in a life cycle and risk assessments perspective.

    PubMed

    Adam, Véronique; Loyaux-Lawniczak, Stéphanie; Quaranta, Gaetana

    2015-08-01

    For the last 10 years, engineered nanomaterials (ENMs) have raised interest to industrials due to their properties. They are present in a large variety of products from cosmetics to building materials through food additives, and their value on the market was estimated to reach $3 trillion in 2014 (Technology Strategy Board 2009). TiO2 NMs represent the second most important part of ENMs production worldwide (550-5500 t/year). However, a gap of knowledge remains regarding the fate and the effects of these, and consequently, impact and risk assessments are challenging. This is due to difficulties in not only characterizing NMs but also in selecting the NM properties which could contribute most to ecotoxicity and human toxicity. Characterizing NMs should thus rely on various analytical techniques in order to evaluate several properties and to crosscheck the results. The aims of this review are to understand the fate and effects of TiO2 NMs in water, sediment, and soil and to determine which of their properties need to be characterized, to assess the analytical techniques available for their characterization, and to discuss the integration of specific properties in the Life Cycle Assessment and Risk Assessment calculations. This study underlines the need to take into account nano-specific properties in the modeling of their fate and effects. Among them, crystallinity, size, aggregation state, surface area, and particle number are most significant. This highlights the need for adapting ecotoxicological studies to NP-specific properties via new methods of measurement and new metrics for ecotoxicity thresholds. PMID:25994264

  10. Biomonitoring as a tool in the human health risk characterization of dermal exposure.

    PubMed

    Boogaard, P J

    2008-04-01

    Dermal exposure is an important factor in risk characterization. In occupational settings it becomes relatively more important because of the continuous reduction in inhalation exposure. In the public health arena, dermal exposure may also form a significant contribution to the total exposure. Dermal exposure, however, is difficult to assess directly because it is determined by a host of factors, which are difficult to quantify. As a consequence, dermal exposure is often estimated by application of models for external exposure. In combination with modeled or measured data for percutaneous penetration, these provide an estimate for the internal exposure that is directly related to the systemic effects. The advantages and drawbacks of EASE (Estimation and Assessment of Substance Exposure) and RISKOFDERM (Risk Assessment of Occupational Dermal Exposure), two models for external exposure that are mentioned in the Technical Guidance Document for the European Union risk assessments performed under the Existing Substances Regulation (EEC/793/93), are discussed. Although new chemicals regulation (REACh, 1907/2006/EC) is now in place in the European Union, the principles applied under the previous legislation do not change and the same models will continue to be used. The results obtained with these models for styrene, 2-butoxyethanol, and 1-methoxy-2-propanol in specific exposure scenarios are compared with an alternative method that uses biomonitoring data to assess dermal exposure. Actual external exposure measurements combined with measured or modeled percutaneous penetration data give acceptable results in risk assessment of dermal exposure, but modeled data of external dermal exposure should only be used if no other data are available. However, if available, biomonitoring should be considered the method of choice to assess (dermal) exposure. PMID:18684800

  11. Characterization of the Risks of Adverse Outcomes Following Rubella Infection in Pregnancy.

    PubMed

    Thompson, Kimberly M; Simons, Emily A; Badizadegan, Kamran; Reef, Susan E; Cooper, Louis Z

    2016-07-01

    Although most infections with the rubella virus result in relatively minor sequelae, rubella infection in early pregnancy may lead to severe adverse outcomes for the fetus. First recognized in 1941, congenital rubella syndrome (CRS) can manifest with a diverse range of symptoms, including congenital cataracts, glaucoma, and cardiac defects, as well as hearing and intellectual disability. The gestational age of the fetus at the time of the maternal rubella infection impacts the probability and severity of outcomes, with infection in early pregnancy increasing the risks of spontaneous termination (miscarriage), fetal death (stillbirth), birth defects, and reduced survival for live-born infants. Rubella vaccination continues to change the epidemiology of rubella and CRS globally, but no models currently exist to evaluate the economic benefits of rubella management. This systematic review provides an overall assessment of the weight of the evidence for the outcomes associated with rubella infections in the first 20 weeks of pregnancy. We identified, evaluated, and graded 31 studies (all from developed countries) that reported on the pregnancy outcomes of at least 30 maternal rubella infections. We used the available evidence to estimate the increased risks of spontaneous termination, fetal death, infant death, and CRS as a function of the timing of rubella infection in pregnancy and decisions about induced termination. These data support the characterization of the disability-adjusted life years for outcomes associated with rubella infection in pregnancy. We find significant impacts associated with maternal rubella infections in early pregnancy, which economic analyses will miss if they only focus on live births of CRS cases. Our estimates of fetal loss from increased induced terminations due to maternal rubella infections provide context that may help to explain the relatively low numbers of observed CRS cases per year despite potentially large burdens of disease. Our

  12. Characterizing the Epidemiological Transition in Mexico: National and Subnational Burden of Diseases, Injuries, and Risk Factors

    PubMed Central

    Stevens, Gretchen; Dias, Rodrigo H; Thomas, Kevin J. A; Rivera, Juan A; Carvalho, Natalie; Barquera, Simón; Hill, Kenneth; Ezzati, Majid

    2008-01-01

    Background Rates of diseases and injuries and the effects of their risk factors can have substantial subnational heterogeneity, especially in middle-income countries like Mexico. Subnational analysis of the burden of diseases, injuries, and risk factors can improve characterization of the epidemiological transition and identify policy priorities. Methods and Findings We estimated deaths and loss of healthy life years (measured in disability-adjusted life years [DALYs]) in 2004 from a comprehensive list of diseases and injuries, and 16 major risk factors, by sex and age for Mexico and its states. Data sources included the vital statistics, national censuses, health examination surveys, and published epidemiological studies. Mortality statistics were adjusted for underreporting, misreporting of age at death, and for misclassification and incomparability of cause-of-death assignment. Nationally, noncommunicable diseases caused 75% of total deaths and 68% of total DALYs, with another 14% of deaths and 18% of DALYs caused by undernutrition and communicable, maternal, and perinatal diseases. The leading causes of death were ischemic heart disease, diabetes mellitus, cerebrovascular disease, liver cirrhosis, and road traffic injuries. High body mass index, high blood glucose, and alcohol use were the leading risk factors for disease burden, causing 5.1%, 5.0%, and 7.3% of total burden of disease, respectively. Mexico City had the lowest mortality rates (4.2 per 1,000) and the Southern region the highest (5.0 per 1,000); under-five mortality in the Southern region was nearly twice that of Mexico City. In the Southern region undernutrition and communicable, maternal, and perinatal diseases caused 23% of DALYs; in Chiapas, they caused 29% of DALYs. At the same time, the absolute rates of noncommunicable disease and injury burdens were highest in the Southern region (105 DALYs per 1,000 population versus 97 nationally for noncommunicable diseases; 22 versus 19 for injuries

  13. [Uncertainty characterization approaches for ecological risk assessment of polycyclic aromatic hydrocarbon in Taihu Lake].

    PubMed

    Guo, Guang-Hui; Wu, Feng-Chang; He, Hong-Ping; Feng, Cheng-Lian; Zhang, Rui-Qing; Li, Hui-Xian

    2012-04-01

    Probabilistic approaches, such as Monte Carlo Sampling (MCS) and Latin Hypercube Sampling (LHS), and non-probabilistic approaches, such as interval analysis, fuzzy set theory and variance propagation, were used to characterize uncertainties associated with risk assessment of sigma PAH8 in surface water of Taihu Lake. The results from MCS and LHS were represented by probability distributions of hazard quotients of sigma PAH8 in surface waters of Taihu Lake. The probabilistic distribution of hazard quotient were obtained from the results of MCS and LHS based on probabilistic theory, which indicated that the confidence intervals of hazard quotient at 90% confidence level were in the range of 0.000 18-0.89 and 0.000 17-0.92, with the mean of 0.37 and 0.35, respectively. In addition, the probabilities that the hazard quotients from MCS and LHS exceed the threshold of 1 were 9.71% and 9.68%, respectively. The sensitivity analysis suggested the toxicity data contributed the most to the resulting distribution of quotients. The hazard quotient of sigma PAH8 to aquatic organisms ranged from 0.000 17 to 0.99 using interval analysis. The confidence interval was (0.001 5, 0.016 3) at the 90% confidence level calculated using fuzzy set theory, and the confidence interval was (0.000 16, 0.88) at the 90% confidence level based on the variance propagation. These results indicated that the ecological risk of sigma PAH8 to aquatic organisms were low. Each method has its own set of advantages and limitations, which was based on different theory; therefore, the appropriate method should be selected on a case-by-case to quantify the effects of uncertainties on the ecological risk assessment. Approach based on the probabilistic theory was selected as the most appropriate method to assess the risk of sigma PAH8 in surface water of Taihu Lake, which provided an important scientific foundation of risk management and control for organic pollutants in water. PMID:22720551

  14. Molecular Characterization and Risk Factors of Giardia duodenalis among School Children from La Habana, Cuba.

    PubMed

    Jerez Puebla, Luis Enrique; Núñez, Fidel A; Martínez Silva, Isabel; Rojas Rivero, Lázara; Martínez González, Marta; Méndez Sutil, Yuliet; Ayllón Valdés, Lucía; Atencio Millán, Iraís; Müller, Norbert

    2015-01-01

    Giardia duodenalis is considered the most common protozoan infecting humans worldwide. Molecular characterization of G. duodenalis isolates has revealed the existence of eight groups (assemblages A to H) which differ in their host distribution. A cross-sectional study was conducted in 639 children from La Habana between January and December 2013. Two assemblage-specific PCRs were carried out for the molecular characterization. The overall prevalence of Giardia infection was 11.9%. DNA from 63 of 76 (82.9%) samples was successfully amplified by PCR-tpi, while 58 from 76 (76.3%) were detected by PCRE1-HF. Similar results by both PCRs were obtained in 54 from 76 samples (71%). According to these analyses, assemblage B and mixed assemblages A + B account for most of the Giardia infections in the cohort of children tested. Our current study identified assemblage B as predominant genotype in children infected with Giardia. Univariate analysis indicated that omission of washing hands before eating and keeping dogs at home were significant risk factors for a Giardia infection. In the future, novel molecular tools for a better discrimination of assemblages at the subassemblages level are needed to verify possible correlations between Giardia genotypes and symptomatology of giardiasis. PMID:26693345

  15. Molecular Characterization and Risk Factors of Giardia duodenalis among School Children from La Habana, Cuba

    PubMed Central

    Jerez Puebla, Luis Enrique; Núñez, Fidel A.; Martínez Silva, Isabel; Rojas Rivero, Lázara; Martínez González, Marta; Méndez Sutil, Yuliet; Ayllón Valdés, Lucía; Atencio Millán, Iraís; Müller, Norbert

    2015-01-01

    Giardia duodenalis is considered the most common protozoan infecting humans worldwide. Molecular characterization of G. duodenalis isolates has revealed the existence of eight groups (assemblages A to H) which differ in their host distribution. A cross-sectional study was conducted in 639 children from La Habana between January and December 2013. Two assemblage-specific PCRs were carried out for the molecular characterization. The overall prevalence of Giardia infection was 11.9%. DNA from 63 of 76 (82.9%) samples was successfully amplified by PCR-tpi, while 58 from 76 (76.3%) were detected by PCRE1-HF. Similar results by both PCRs were obtained in 54 from 76 samples (71%). According to these analyses, assemblage B and mixed assemblages A + B account for most of the Giardia infections in the cohort of children tested. Our current study identified assemblage B as predominant genotype in children infected with Giardia. Univariate analysis indicated that omission of washing hands before eating and keeping dogs at home were significant risk factors for a Giardia infection. In the future, novel molecular tools for a better discrimination of assemblages at the subassemblages level are needed to verify possible correlations between Giardia genotypes and symptomatology of giardiasis. PMID:26693345

  16. Pseudomonas aeruginosa isolates in severe chronic obstructive pulmonary disease: characterization and risk factors

    PubMed Central

    2014-01-01

    Background Patients with severe chronic obstructive pulmonary disease (COPD) are at increased risk of infection by P. aeruginosa. The specific role of bronchiectasis in both infection and chronic colonization by this microorganism in COPD, however, remains ill defined. To evaluate the prevalence and risk factors for P. aeruginosa recovery from sputum in outpatients with severe COPD, characterizing P. aeruginosa isolates by pulsed-field gel electrophoresis (PFGE) and focusing on the influence of bronchiectasis on chronic colonization in these patients. Methods A case-cohort study of 118 patients with severe COPD attended at a Respiratory Day Unit for an acute infectious exacerbation and followed up over one year. High-resolution CT scans were performed during stability for bronchiectasis assessment and sputum cultures were obtained during exacerbation and stability in all patients. P. aeruginosa isolates were genotyped by PFGE. Determinants of the recovery of P. aeruginosa in sputum and chronic colonization by this microorganism were assessed by multivariate analysis. Results P. aeruginosa was isolated from 41 of the 118 patients studied (34.7%). Five of these 41 patients (12.2%) with P. aeruginosa recovery fulfilled criteria for chronic colonization. In the multivariate analysis, the extent of bronchiectasis (OR 9.8, 95% CI: 1.7 to 54.8) and the number of antibiotic courses (OR 1.7, 95% CI: 1.1 to 2.5) were independently associated with an increased risk of P. aeruginosa isolation. Chronic colonization was unrelated to the presence of bronchiectasis (p=0.75). In patients with chronic colonization the isolates of P. aeruginosa retrieved corresponded to the same clones during the follow-up, and most of the multidrug resistant isolates (19/21) were harbored by these patients. Conclusions The main risk factors for P. aeruginosa isolation in severe COPD were the extent of bronchiectasis and exposure to antibiotics. Over 10% of these patients fulfilled criteria for

  17. Characterization of the human kinetic adjustment factor for the health risk assessment of environmental contaminants.

    PubMed

    Valcke, Mathieu; Krishnan, Kannan

    2014-03-01

    A default uncertainty factor of 3.16 (√10) is applied to account for interindividual variability in toxicokinetics when performing non-cancer risk assessments. Using relevant human data for specific chemicals, as WHO/IPCS suggests, it is possible to evaluate, and replace when appropriate, this default factor by quantifying chemical-specific adjustment factors for interindividual variability in toxicokinetics (also referred to as the human kinetic adjustment factor, HKAF). The HKAF has been determined based on the distributions of pharmacokinetic parameters (e.g., half-life, area under the curve, maximum blood concentration) in relevant populations. This article focuses on the current state of knowledge of the use of physiologically based algorithms and models in characterizing the HKAF for environmental contaminants. The recent modeling efforts on the computation of HKAF as a function of the characteristics of the population, chemical and its mode of action (dose metrics), as well as exposure scenario of relevance to the assessment are reviewed here. The results of these studies, taken together, suggest the HKAF varies as a function of the sensitive subpopulation and dose metrics of interest, exposure conditions considered (route, duration, and intensity), metabolic pathways involved and theoretical model underlying its computation. The HKAF seldom exceeded the default value of 3.16, except in very young children (i.e., <≈ 3 months) and when the parent compound is the toxic moiety. Overall, from a public health perspective, the current state of knowledge generally suggest that the default uncertainty factor is sufficient to account for human variability in non-cancer risk assessments of environmental contaminants. PMID:24038072

  18. Characterization of backyard poultry production systems and disease risk in the central zone of Chile.

    PubMed

    Hamilton-West, C; Rojas, H; Pinto, J; Orozco, J; Hervé-Claude, L P; Urcelay, S

    2012-08-01

    Backyard poultry production systems (BPS) are an important and widespread form of poultry production. There is a common perception that biosecurity standards in BPS are generally poor and BPS are usually associated with animal diseases and zoonoses. In this study BPS were identified in the vicinity of six wetlands, having these a higher risk of presenting and introducing avian diseases such as HPAI and Newcastle disease, as defined by the national veterinary services, in to Chile's main poultry production area. BPS were characterized through a field questionnaire and the main areas covered by the survey were BPS structure, biosecurity and value chain. The BPS identified in this study share most characteristics on biosecurity, poultry management and product commercialization, but it was possible to identify a certain degree of variation within and among the study sites. BPS in Chile are similar to those in other regions, with a relatively small flock size (average 37 birds), a low level of biosecurity measures and lack of poultry disease management. Management findings include that most farmers used mixed/partial confinement, with low or no biosecurity and disease control measures in place. Eggs were the main output and were used mainly for home consumption or sale at local markets. Sick birds' treatment with drugs approved for other species or for human use could represent a risk to human health, owing to the possible presence of drug residues in poultry products. Despite the different structures of the poultry sector worldwide, BPS can play a major role in disease maintenance and spread because its management conditions characteristics and the lack of animal health services adapted to these production systems. This should be an alert message to the veterinary authorities to improve coverage of veterinary assistance and surveillance activities in backyard poultry production. PMID:21752410

  19. Characterizing trabecular bone structure for assessing vertebral fracture risk on volumetric quantitative computed tomography

    NASA Astrophysics Data System (ADS)

    Nagarajan, Mahesh B.; Checefsky, Walter A.; Abidin, Anas Z.; Tsai, Halley; Wang, Xixi; Hobbs, Susan K.; Bauer, Jan S.; Baum, Thomas; Wismüller, Axel

    2015-03-01

    While the proximal femur is preferred for measuring bone mineral density (BMD) in fracture risk estimation, the introduction of volumetric quantitative computed tomography has revealed stronger associations between BMD and spinal fracture status. In this study, we propose to capture properties of trabecular bone structure in spinal vertebrae with advanced second-order statistical features for purposes of fracture risk assessment. For this purpose, axial multi-detector CT (MDCT) images were acquired from 28 spinal vertebrae specimens using a whole-body 256-row CT scanner with a dedicated calibration phantom. A semi-automated method was used to annotate the trabecular compartment in the central vertebral slice with a circular region of interest (ROI) to exclude cortical bone; pixels within were converted to values indicative of BMD. Six second-order statistical features derived from gray-level co-occurrence matrices (GLCM) and the mean BMD within the ROI were then extracted and used in conjunction with a generalized radial basis functions (GRBF) neural network to predict the failure load of the specimens; true failure load was measured through biomechanical testing. Prediction performance was evaluated with a root-mean-square error (RMSE) metric. The best prediction performance was observed with GLCM feature `correlation' (RMSE = 1.02 ± 0.18), which significantly outperformed all other GLCM features (p < 0.01). GLCM feature correlation also significantly outperformed MDCTmeasured mean BMD (RMSE = 1.11 ± 0.17) (p< 10-4). These results suggest that biomechanical strength prediction in spinal vertebrae can be significantly improved through characterization of trabecular bone structure with GLCM-derived texture features.

  20. Brain network characterization of high-risk preterm-born school-age children

    PubMed Central

    Fischi-Gomez, Elda; Muñoz-Moreno, Emma; Vasung, Lana; Griffa, Alessandra; Borradori-Tolsa, Cristina; Monnier, Maryline; Lazeyras, François; Thiran, Jean-Philippe; Hüppi, Petra S.

    2016-01-01

    Higher risk for long-term cognitive and behavioral impairments is one of the hallmarks of extreme prematurity (EP) and pregnancy-associated fetal adverse conditions such as intrauterine growth restriction (IUGR). While neurodevelopmental delay and abnormal brain function occur in the absence of overt brain lesions, these conditions have been recently associated with changes in microstructural brain development. Recent imaging studies indicate changes in brain connectivity, in particular involving the white matter fibers belonging to the cortico-basal ganglia-thalamic loop. Furthermore, EP and IUGR have been related to altered brain network architecture in childhood, with reduced network global capacity, global efficiency and average nodal strength. In this study, we used a connectome analysis to characterize the structural brain networks of these children, with a special focus on their topological organization. On one hand, we confirm the reduced averaged network node degree and strength due to EP and IUGR. On the other, the decomposition of the brain networks in an optimal set of clusters remained substantially different among groups, talking in favor of a different network community structure. However, and despite the different community structure, the brain networks of these high-risk school-age children maintained the typical small-world, rich-club and modularity characteristics in all cases. Thus, our results suggest that brain reorganizes after EP and IUGR, prioritizing a tight modular structure, to maintain the small-world, rich-club and modularity characteristics. By themselves, both extreme prematurity and IUGR bear a similar risk for neurocognitive and behavioral impairment, and the here defined modular network alterations confirm similar structural changes both by IUGR and EP at school age compared to control. Interestingly, the combination of both conditions (IUGR + EP) does not result in a worse outcome. In such cases, the alteration in network

  1. Case Characterization, Clinical Features and Risk Factors in Drug-Induced Liver Injury.

    PubMed

    Ortega-Alonso, Aida; Stephens, Camilla; Lucena, M Isabel; Andrade, Raúl J

    2016-01-01

    Idiosyncratic drug-induced liver injury (DILI) caused by xenobiotics (drugs, herbals and dietary supplements) presents with a range of both phenotypes and severity, from acute hepatitis indistinguishable of viral hepatitis to autoimmune syndromes, steatosis or rare chronic vascular syndromes, and from asymptomatic liver test abnormalities to acute liver failure. DILI pathogenesis is complex, depending on the interaction of drug physicochemical properties and host factors. The awareness of risk factors for DILI is arising from the analysis of large databases of DILI cases included in Registries and Consortia networks around the world. These networks are also enabling in-depth phenotyping with the identification of predictors for severe outcome, including acute liver failure and mortality/liver transplantation. Genome wide association studies taking advantage of these large cohorts have identified several alleles from the major histocompatibility complex system indicating a fundamental role of the adaptive immune system in DILI pathogenesis. Correct case definition and characterization is crucial for appropriate phenotyping, which in turn will strengthen sample collection for genotypic and future biomarkers studies. PMID:27187363

  2. The Next Challenge for Psychiatric Genetics: Characterizing the Risk Associated with Identified Genes

    PubMed Central

    Dick, Danielle M.; Rose, Richard J.; Kaprio, Jaakko

    2006-01-01

    Background As advances in genetics further our ability to identify genes influencing psychiatric disorders, the next challenge facing psychiatric genetics is to characterize the risk associated with specific genetic variants in order to better understand how these susceptibility genes are involved in the pathways leading to illness. Methods To further this goal, findings from behavior genetic analyses about how genetic influences act can be used to guide hypothesis testing about the effects associated with specific genes. Results Using the phenotype of alcohol dependence as an example, this paper provides an overview of how the integration of behavioral and statistical genetics can advance our knowledge about the genetics of psychiatric disorders. Areas currently being investigated in behavior genetics include careful delineation of phenotypes, to examine the heritability of various aspects of normal and abnormal behavior; developmental changes in the nature and magnitude of genetic and environmental effects; the extent to which different behaviors are influenced by common genes; and different forms of gene-environment correlation and interaction. Conclusions Understanding how specific genes are involved in these processes has the potential to significantly enhance our understanding of the development of psychiatric disorders. PMID:17162621

  3. Case Characterization, Clinical Features and Risk Factors in Drug-Induced Liver Injury

    PubMed Central

    Ortega-Alonso, Aida; Stephens, Camilla; Lucena, M. Isabel; Andrade, Raúl J.

    2016-01-01

    Idiosyncratic drug-induced liver injury (DILI) caused by xenobiotics (drugs, herbals and dietary supplements) presents with a range of both phenotypes and severity, from acute hepatitis indistinguishable of viral hepatitis to autoimmune syndromes, steatosis or rare chronic vascular syndromes, and from asymptomatic liver test abnormalities to acute liver failure. DILI pathogenesis is complex, depending on the interaction of drug physicochemical properties and host factors. The awareness of risk factors for DILI is arising from the analysis of large databases of DILI cases included in Registries and Consortia networks around the world. These networks are also enabling in-depth phenotyping with the identification of predictors for severe outcome, including acute liver failure and mortality/liver transplantation. Genome wide association studies taking advantage of these large cohorts have identified several alleles from the major histocompatibility complex system indicating a fundamental role of the adaptive immune system in DILI pathogenesis. Correct case definition and characterization is crucial for appropriate phenotyping, which in turn will strengthen sample collection for genotypic and future biomarkers studies. PMID:27187363

  4. CHARACTERIZE AGGREGATE AND CUMULATIVE RISK TO MANAGE RISK TO HUMANS EXPOSED TO MULTIPLE ENVIRONMENTAL STRESSORS: INTERACTION STUDIES FOR PESTICIDE MIXTURES

    EPA Science Inventory

    SUMMARY: The Agency’s default assumption for the cumulative assessment of the risk of mixtures is additivity based on either single-chemical potency (dose addition) or single-chemical effects (effect addition). NTD is developing models to accurately predict effects of complex mix...

  5. Risk.

    PubMed

    Cole, Stephen R; Hudgens, Michael G; Brookhart, M Alan; Westreich, Daniel

    2015-02-15

    The epidemiologist primarily studies transitions between states of health and disease. The purpose of the present article is to define a foundational parameter for such studies, namely risk. We begin simply and build to the setting in which there is more than 1 event type (i.e., competing risks or competing events), as well as more than 1 treatment or exposure level of interest. In the presence of competing events, the risks are a set of counterfactual cumulative incidence functions for each treatment. These risks can be depicted visually and summarized numerically. We use an example from the study of human immunodeficiency virus to illustrate concepts. PMID:25660080

  6. Integrating mechanistic and polymorphism data to characterize human genetic susceptibility for environmental chemical risk assessment in the 21st century.

    PubMed

    Mortensen, Holly M; Euling, Susan Y

    2013-09-15

    Response to environmental chemicals can vary widely among individuals and between population groups. In human health risk assessment, data on susceptibility can be utilized by deriving risk levels based on a study of a susceptible population and/or an uncertainty factor may be applied to account for the lack of information about susceptibility. Defining genetic susceptibility in response to environmental chemicals across human populations is an area of interest in the NAS' new paradigm of toxicity pathway-based risk assessment. Data from high-throughput/high content (HT/HC), including -omics (e.g., genomics, transcriptomics, proteomics, metabolomics) technologies, have been integral to the identification and characterization of drug target and disease loci, and have been successfully utilized to inform the mechanism of action for numerous environmental chemicals. Large-scale population genotyping studies may help to characterize levels of variability across human populations at identified target loci implicated in response to environmental chemicals. By combining mechanistic data for a given environmental chemical with next generation sequencing data that provides human population variation information, one can begin to characterize differential susceptibility due to genetic variability to environmental chemicals within and across genetically heterogeneous human populations. The integration of such data sources will be informative to human health risk assessment. PMID:21291902

  7. Integrating mechanistic and polymorphism data to characterize human genetic susceptibility for environmental chemical risk assessment in the 21st century

    SciTech Connect

    Mortensen, Holly M.; Euling, Susan Y.

    2013-09-15

    Response to environmental chemicals can vary widely among individuals and between population groups. In human health risk assessment, data on susceptibility can be utilized by deriving risk levels based on a study of a susceptible population and/or an uncertainty factor may be applied to account for the lack of information about susceptibility. Defining genetic susceptibility in response to environmental chemicals across human populations is an area of interest in the NAS' new paradigm of toxicity pathway-based risk assessment. Data from high-throughput/high content (HT/HC), including -omics (e.g., genomics, transcriptomics, proteomics, metabolomics) technologies, have been integral to the identification and characterization of drug target and disease loci, and have been successfully utilized to inform the mechanism of action for numerous environmental chemicals. Large-scale population genotyping studies may help to characterize levels of variability across human populations at identified target loci implicated in response to environmental chemicals. By combining mechanistic data for a given environmental chemical with next generation sequencing data that provides human population variation information, one can begin to characterize differential susceptibility due to genetic variability to environmental chemicals within and across genetically heterogeneous human populations. The integration of such data sources will be informative to human health risk assessment.

  8. Changes in free amino acid, phenolic, chlorophyll, carotenoid, and glycoalkaloid contents in tomatoes during 11 stages of growth and inhibition of cervical and lung human cancer cells by green tomato extracts.

    PubMed

    Choi, Suk-Hyun; Lee, Sang-Hwa; Kim, Hyun-Jeong; Lee, In-Seon; Kozukue, Nobuyuki; Levin, Carol E; Friedman, Mendel

    2010-07-14

    Tomato ( Solanum lycopersicum ) plants synthesize nutrients, pigments, and secondary metabolites that benefit nutrition and human health. The concentrations of these compounds are strongly influenced by the maturity of the tomato fruit on the vine. Widely consumed Korean tomatoes of the variety Doturakworld were analyzed for changes in the content of free amino acids, phenolic compounds, chlorophylls, carotenoids, and glycoalkaloids at 11 stages (S1-S11) of ripeness. The results show that (a) the total content (in mg/100 g of FW) of the free amino acids and other nitrogen-containing compounds in the extracts ranged from about 41 to 85 in the green tomato extracts S1-S7 and then increased to 251 (S9) in the red extracts, followed by a decrease to 124 in S11 red extracts; (b) the total initial concentration and composition of up to 12 phenolic compounds of approximately 2000 microg/100 g of FW varied throughout the ripening process, with the quantity decreasing and the number of individual compounds increasing in the red tomato; (c) chlorophyll a and b content of tomatoes harvested during S1 was 5.73 mg/100 g of fresh pericarp and then decreased continuously to 1.14 mg/100 g for S11; (d) the concentration (in mg/100 g of FW) of lycopene in the S8 red extract of 0.32 increased to 1.27 in S11; and (e) tomatoes harvested during S1 contained 48.2 mg of dehydrotomatine/100 g of FW, and this value continually decreased to 1.5 in S7, with no detectable levels in S8-S11. The corresponding alpha-tomatine content decreased from S1 (361) to S8 (13.8). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell assay IC(50) values showed that Hel299 lung cells, A549 lung cancer cells, and HeLa cervical carcinoma cells were highly susceptible to inactivation by glycoalkaloid-rich green tomato extracts. Chang normal liver cells and U937 lymphoma cells were less susceptible. The possible significance of the results for plant physiology and the diet is discussed

  9. Integrating Safety Assessment Methods using the Risk Informed Safety Margins Characterization (RISMC) Approach

    SciTech Connect

    Curtis Smith; Diego Mandelli

    2013-03-01

    Safety is central to the design, licensing, operation, and economics of nuclear power plants (NPPs). As the current light water reactor (LWR) NPPs age beyond 60 years, there are possibilities for increased frequency of systems, structures, and components (SSC) degradations or failures that initiate safety significant events, reduce existing accident mitigation capabilities, or create new failure modes. Plant designers commonly “over-design” portions of NPPs and provide robustness in the form of redundant and diverse engineered safety features to ensure that, even in the case of well-beyond design basis scenarios, public health and safety will be protected with a very high degree of assurance. This form of defense-in-depth is a reasoned response to uncertainties and is often referred to generically as “safety margin.” Historically, specific safety margin provisions have been formulated primarily based on engineering judgment backed by a set of conservative engineering calculations. The ability to better characterize and quantify safety margin is important to improved decision making about LWR design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margin management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. In addition, as research and development (R&D) in the LWR Sustainability (LWRS) Program and other collaborative efforts yield new data, sensors, and improved scientific understanding of physical processes that govern the aging and degradation of plant SSCs needs and opportunities to better optimize plant safety and performance will become known. To support decision making related to economics, readability, and safety, the RISMC Pathway provides methods and tools that enable mitigation options known as margins management strategies. The purpose of the RISMC Pathway R&D is to support plant decisions for risk

  10. Genomic characterization of esophageal squamous cell carcinoma from a high-risk population in China

    PubMed Central

    Hu, Nan; Wang, Chaoyu; Ng, David; Clifford, Robert; Yang, Howard H; Tang, Ze-Zhong; Wang, Quan-Hong; Han, Xiao-You; Giffen, Carol; Goldstein, Alisa M; Taylor, Philip R; Lee, Maxwell P

    2009-01-01

    Genomic instability plays an important role in most human cancers. To characterize genomic instability in esophageal squamous cell carcinoma (ESCC), we examined loss of heterozygosity (LOH), copy number (CN) loss, CN gain, and gene expression using the Affymetrix GeneChip Human Mapping 500K (n=30 cases) and Human U133A (n=17 cases) arrays in ESCC cases from a high-risk region of China. We found that genomic instability measures varied widely among cases and separated them into two groups: a high-frequency instability group (two-thirds of all cases with one or more instability category ≥ 10%) and a low-frequency instability group (one-third of cases with instability < 10%). Genomic instability also varied widely across chromosomal arms, with the highest frequency of LOH on 9p (33% of informative single nucleotide polymorphisms (SNPs)), CN loss on 3p (33%), and CN gain on 3q (48%). Twenty-two LOH regions were identified: four on 9p, seven on 9q, four on 13q, two on 17p, and five on 17q. Three CN loss regions – 3p12.3, 4p15.1, and 9p21.3 – were detected. Twelve CN gain regions were found, including six on 3q, one on 7q, four on 8q, and one on 11q. One of the most gene-rich of these CN gain regions was 11q13.1-13.4, where 26 genes also had RNA expression data available. CN gain was significantly correlated with increased RNA expression in over 80% of these genes. Our findings demonstrate the potential utility of combining CN analysis and gene expression data to identify genes involved in esophageal carcinogenesis. PMID:19584285

  11. Preliminary characterization of risks in the nuclear waste management system based on information in the literature

    SciTech Connect

    Daling, P.M.; Rhoads, R.E.; Van Luick, A.E.; Fecht, B.A.; Nilson, S.A.; Sevigny, N.L.; Armstrong, G.R.; Hill, D.H.; Rowe, M.; Stern, E.

    1992-01-01

    This document presents preliminary information on the radiological and nonradiological risks in the nuclear waste management system. The objective of the study was to (1) review the literature containing information on risks in the nuclear waste management system and (2) use this information to develop preliminary estimates of the potential magnitude of these risks. Information was collected on a broad range of risk categories to assist the US Department of Energy (DOE) in communicating information about the risks in the waste management systems. The study examined all of the portions of the nuclear waste management system currently expected to be developed by the DOE. The scope of this document includes the potential repository, the integral MRS facility, and the transportation system that supports the potential repository and the MRS facility. Relevant literature was reviewed for several potential repository sites and geologic media. A wide range of ``risk categories`` are addressed in this report: (1) public and occupational risks from accidents that could release radiological materials, (2) public and occupational radiation exposure resulting from routine operations, (3) public and occupational risks from accidents involving hazards other than radioactive materials, and (4) public and occupational risks from exposure to nonradioactive hazardous materials during routine operations. The report is intended to provide a broad spectrum of risk-related information about the waste management system. This information is intended to be helpful for planning future studies.

  12. Depleted uranium risk assessment for Jefferson Proving Ground using data from environmental monitoring and site characterization. Final report

    SciTech Connect

    Ebinger, M.H.; Hansen, W.R.

    1996-10-01

    This report documents the third risk assessment completed for the depleted uranium (DU) munitions testing range at Jefferson Proving Ground (JPG), Indiana, for the U.S. Army Test and Evaluation command. Jefferson Proving Ground was closed in 1995 under the Base Realignment and Closure Act and the testing mission was moved to Yuma Proving Ground. As part of the closure of JPG, assessments of potential adverse health effects to humans and the ecosystem were conducted. This report integrates recent information obtained from site characterization surveys at JPG with environmental monitoring data collected from 1983 through 1994 during DU testing. Three exposure scenarios were evaluated for potential adverse effects to human health: an occasional use scenario and two farming scenarios. Human exposure was minimal from occasional use, but significant risk were predicted from the farming scenarios when contaminated groundwater was used by site occupants. The human health risk assessments do not consider the significant risk posed by accidents with unexploded ordnance. Exposures of white-tailed deer to DU were also estimated in this study, and exposure rates result in no significant increase in either toxicological or radiological risks. The results of this study indicate that remediation of the DU impact area would not substantially reduce already low risks to humans and the ecosystem, and that managed access to JPG is a reasonable model for future land use options.

  13. Methodology for characterizing high-risk orbital debris in the geosynchronous orbit regime

    NASA Astrophysics Data System (ADS)

    Anderson, Paul V.; Schaub, Hanspeter

    2016-01-01

    Forecasting of localized debris congestion in the geostationary (GEO) ring is performed to formulate and investigate methodology for identifying the debris objects that pose the highest risk to operational satellites in this ring. Proximity and speed relative to GEO during near-miss events detected under a torus intersection metric are translated into a combined risk factor that is accumulated during propagation. This accumulated risk is then used to identify the objects that have the highest risk contributions, either globally or in the vicinity of one of the two gravitational wells at 75°E and 105°W. Results show that nearly 60% of the total risk surrounding the Western well is attributed to 10 derelicts alone, which has critical implications for active debris removal (ADR) target selection for attenuating risk levels in this ring.

  14. The Development of Dynamic Human Reliability Analysis Simulations for Inclusion in Risk Informed Safety Margin Characterization Frameworks

    SciTech Connect

    Jeffrey C. Joe; Diego Mandelli; Ronald L. Boring; Curtis L. Smith; Rachel B. Shirley

    2015-07-01

    The United States Department of Energy is sponsoring the Light Water Reactor Sustainability program, which has the overall objective of supporting the near-term and the extended operation of commercial nuclear power plants. One key research and development (R&D) area in this program is the Risk-Informed Safety Margin Characterization pathway, which combines probabilistic risk simulation with thermohydraulic simulation codes to define and manage safety margins. The R&D efforts to date, however, have not included robust simulations of human operators, and how the reliability of human performance or lack thereof (i.e., human errors) can affect risk-margins and plant performance. This paper describes current and planned research efforts to address the absence of robust human reliability simulations and thereby increase the fidelity of simulated accident scenarios.

  15. Risk-based ecological soil quality criteria for the characterization of contaminated soils. Combination of chemical and biological tools.

    PubMed

    Fernández, María Dolores; Vega, María Milagrosa; Tarazona, José Vicente

    2006-08-01

    This paper describes the development of soil quality criteria for the characterization of soils focused on the potential risk to the ecosystem. The approach combines both Generic Soil Quality standards (GSQs) for individual chemicals and direct ecotoxicity assays on soil samples taken from the site. Criteria establish three main risk levels with their corresponding trigger values. The trigger values to determine high risk or "polluted" soils are exclusively based on direct toxicity assessments. The trigger values for the other categories are established by a combination of the application of GSQs and the results of bioassays. Low-risk is assumed when no toxicity is observed and GSQs based on precautionary ecotoxicity thresholds are not exceeded; high-risk must be considered if acute toxicity above the proposed trigger value is observed in soil or leachate samples. In between these levels, the risk cannot be elucidated and a site-specific assessment is required. The GSQs take into account the current or future land use, thus defining three categories: industrial soils, urban/residential soils and natural/agricultural/forest soils, each of them with different ecological requirements. The GSQ values are established following an inverse risk assessment methodology, integrating ecotoxicity and exposure models and setting the soil levels associated to pre-established criteria for the assumption of low risk. The proposed methodology covers all relevant ecological receptors and processes, soil organisms, potential contamination of ground and surface waters, and exposure of terrestrial vertebrates due to bioaccumulation and biomagnification. Exposure routes and protection criteria are defined in each protection goal. The relevance of each receptor and route is established according to the land use. PMID:16574196

  16. Terrestrial eco-risk -- Details and compromises in exposure assessment and risk characterization at Rocky Mountain Arsenal

    SciTech Connect

    Tate, D.J.; Cothern, K.A.; Jones, M.J.; Applehans, F. |; Armstrong, J.P.

    1994-12-31

    The soil and biota databases used to assess terrestrial eco-risk at Rocky Mountain Arsenal reflect considerable spatial variability in soil and biota tissue concentrations. The variability in soil concentrations reflects variability in historical uses of the 27-square mile site, in concentrations of the 14 contaminants of concern (COCS) in soil, and in the distribution of soil borings and surficial soil samples. The spatial variability in tissue concentrations results especially from collection of samples from locations that were biased toward areas associated with high COC concentrations or thought to be uncontaminated and from biota mobility. This variability plus the considerable uncertainty in associating biota tissue concentrations with their exposure soil concentrations resulted in considerable discussion and the development of an innovative and effective protocol for, using interpolated soil concentrations to estimate tissue concentrations that were compared to toxicity reference values for tissue and dose concentrations. Specific examples and the opportunity for discussion of the Endangerment Assessment Technical Subcommittee members` uncharted journey through literature surveys, parameter quantification, statistical nuances, exposure area soil concentration estimation, and development of a proportionality constant (e.g., a site-specific biomagnification factor) to link soil and tissue concentrations will be presented.

  17. The Effects of Revealed Information on Catastrophe Loss Projection Models' Characterization of Risk: Damage Vulnerability Evidence from Florida.

    PubMed

    Karl, J Bradley; Medders, Lorilee A; Maroney, Patrick F

    2016-06-01

    We examine whether the risk characterization estimated by catastrophic loss projection models is sensitive to the revelation of new information regarding risk type. We use commercial loss projection models from two widely employed modeling firms to estimate the expected hurricane losses of Florida Atlantic University's building stock, both including and excluding secondary information regarding hurricane mitigation features that influence damage vulnerability. We then compare the results of the models without and with this revealed information and find that the revelation of additional, secondary information influences modeled losses for the windstorm-exposed university building stock, primarily evidenced by meaningful percent differences in the loss exceedance output indicated after secondary modifiers are incorporated in the analysis. Secondary risk characteristics for the data set studied appear to have substantially greater impact on probable maximum loss estimates than on average annual loss estimates. While it may be intuitively expected for catastrophe models to indicate that secondary risk characteristics hold value for reducing modeled losses, the finding that the primary value of secondary risk characteristics is in reduction of losses in the "tail" (low probability, high severity) events is less intuitive, and therefore especially interesting. Further, we address the benefit-cost tradeoffs that commercial entities must consider when deciding whether to undergo the data collection necessary to include secondary information in modeling. Although we assert the long-term benefit-cost tradeoff is positive for virtually every entity, we acknowledge short-term disincentives to such an effort. PMID:26720056

  18. Children's exposure to harmful elements in toys and low-cost jewelry: characterizing risks and developing a comprehensive approach.

    PubMed

    Guney, Mert; Zagury, Gerald J

    2014-04-30

    Contamination problem in jewelry and toys and children's exposure possibility have been previously demonstrated. For this study, risk from oral exposure has been characterized for highly contaminated metallic toys and jewelry ((MJ), n=16) considering three scenarios. Total and bioaccessible concentrations of Cd, Cu, Ni, and Pb were high in selected MJ. First scenario (ingestion of parts or pieces) caused unacceptable risk for eight items for Cd, Ni, and/or Pb (hazard index (HI)>1, up to 75, 5.8, and 43, respectively). HI for ingestion of scraped-off material scenario was always <1. Finally, saliva mobilization scenario caused HI>1 in three samples (two for Cd, one for Ni). Risk characterization identified different potentially hazardous items compared to United States, Canadian, and European Union approaches. A comprehensive approach was also developed to deal with complexity and drawbacks caused by various toy/jewelry definitions, test methods, exposure scenarios, and elements considered in different regulatory approaches. It includes bioaccessible limits for eight priority elements (As, Cd, Cr, Cu, Hg, Ni, Pb, and Sb). Research is recommended on metals bioaccessibility determination in toys/jewelry, in vitro bioaccessibility test development, estimation of material ingestion rates and frequency, presence of hexavalent Cr and organic Sn, and assessment of prolonged exposure to MJ. PMID:24641994

  19. Characterization of ecological risks from environmental releases of decamethylcyclopentasiloxane (D5).

    PubMed

    Fairbrother, Anne; Burton, G Allen; Klaine, Stephen J; Powell, David E; Staples, Charles A; Mihaich, Ellen M; Woodburn, Kent B; Gobas, Frank A P C

    2015-12-01

    Decamethylcyclopentasiloxane (D5) is used in personal care products and industrial applications. The authors summarize the risks to the environment from D5 based on multiple lines of evidence and conclude that it presents negligible risk. Laboratory and field studies show that D5 is not toxic to aquatic organisms or benthic invertebrates up to its solubility limit in water or porewater or its sorptive capacity in sediment. Comparison of lipid-normalized internal concentrations with measured concentrations in benthos indicates that field-collected organisms do not achieve toxic levels of D5 in their tissues, suggesting negligible risk. Exposure to D5 resulted in a slight reduction of root biomass in barley at test concentrations 2 orders of magnitude greater than measured D5 levels in biosolids-amended soils and more than twice as high as the maximum calculated sorptive capacity of the soil. No effects were observed in soil invertebrates exposed to similar concentrations, indicating that D5 poses a de minimis risk to the terrestrial environment. High rates of metabolism and elimination of D5 compared with uptake rates from food results in biodilution in the food web rather than biomagnification, culminating in de minimis risk to higher trophic level organisms via the food chain. A fugacity approach substantiates all conclusions that were made on a concentration basis. PMID:26211518

  20. Molecular Characterization of High-Risk Human Papillomavirus in Women in Bobo-Dioulasso, Burkina Faso

    PubMed Central

    Traore, Ina Marie Angèle; Dembele, Adama; Obiri-Yeboah, Dorcas; Traore, Germain; Bambara, Moussa; Ouedraogo, Charlemagne; Traore, Yves

    2016-01-01

    High-risk human papillomavirus (HPV) is found in over 99% of cervical cancers. The aim of this study was to determine the prevalence of HPV in a population of women in Bobo-Dioulasso and to identify the high-risk types present in these women. From May to June, 2015, 181 women who came for consultation at the Souro Sanou University Hospital of Bobo-Dioulasso have been included in this study. Uterine endocervical swabs have been taken in these women. DNA obtained by extraction from the samples thus collected was used to determine the prevalence of high-risk human papillomavirus genotypes through real-time PCR. The age of the women ranged from 20 to 56 years with a mean of 35.3 ± 8.1 years. The prevalence of infection by high-risk HPV types was 25.4% (46/181). The most common high-risk HPV genotypes were HPV 39 (18.5%), HPV 52 (16.7%), HPV 18 (14.8%), and HPV 35 (13.0%). HPV 16 which is included in the HPV vaccines was not found in the population studied. This type of study which is the first one in Bobo-Dioulasso has showed a high prevalence of genotypes HPV 39, HPV 52, and HPV 35 which are not yet covered by a vaccine. PMID:27525275

  1. Molecular Characterization of High-Risk Human Papillomavirus in Women in Bobo-Dioulasso, Burkina Faso.

    PubMed

    Traore, Ina Marie Angèle; Zohoncon, Théodora Mahoukèdè; Dembele, Adama; Djigma, Florencia W; Obiri-Yeboah, Dorcas; Traore, Germain; Bambara, Moussa; Ouedraogo, Charlemagne; Traore, Yves; Simpore, Jacques

    2016-01-01

    High-risk human papillomavirus (HPV) is found in over 99% of cervical cancers. The aim of this study was to determine the prevalence of HPV in a population of women in Bobo-Dioulasso and to identify the high-risk types present in these women. From May to June, 2015, 181 women who came for consultation at the Souro Sanou University Hospital of Bobo-Dioulasso have been included in this study. Uterine endocervical swabs have been taken in these women. DNA obtained by extraction from the samples thus collected was used to determine the prevalence of high-risk human papillomavirus genotypes through real-time PCR. The age of the women ranged from 20 to 56 years with a mean of 35.3 ± 8.1 years. The prevalence of infection by high-risk HPV types was 25.4% (46/181). The most common high-risk HPV genotypes were HPV 39 (18.5%), HPV 52 (16.7%), HPV 18 (14.8%), and HPV 35 (13.0%). HPV 16 which is included in the HPV vaccines was not found in the population studied. This type of study which is the first one in Bobo-Dioulasso has showed a high prevalence of genotypes HPV 39, HPV 52, and HPV 35 which are not yet covered by a vaccine. PMID:27525275

  2. Plant characterization of Roundup Ready 2 Yield ® soybean, MON 89788, for use in ecological risk assessment.

    PubMed

    Horak, Michael J; Rosenbaum, Eric W; Kendrick, Daniel L; Sammons, Bernard; Phillips, Samuel L; Nickson, Thomas E; Dobert, Raymond C; Perez, Tim

    2015-04-01

    During the development of a genetically modified (GM) crop product, extensive phenotypic and agronomic data are collected to characterize the plant in comparison to a conventional control with a similar genetic background. The data are evaluated for potential differences resulting from the genetic modification process or the GM trait, and the differences--if any--are subsequently considered in the context of contributing to the pest potential of the GM crop. Ultimately, these study results and those of other studies are used in an ecological risk assessment of the GM crop. In the studies reported here, seed germination, vegetative and reproductive growth, and pollen morphology of Roundup Ready 2 Yield(®) soybean, MON 89788, were compared to those of A3244, a conventional control soybean variety with the same genetic background. Any statistically significant differences were considered in the context of the genetic variation known to occur in soybean and were evaluated as indicators of an effect of the genetic modification process and assessed for impact on plant pest (weed) characteristics and adverse ecological impact (ecological risk). The results of these studies revealed no effects attributable to the genetic modification process or to the GM trait in the plant that would result in increased pest potential or adverse ecological impact of MON 89788 compared with A3244. These results and the associated risk assessments obtained from diverse geographic and environmental conditions in the United States and Argentina can be used by regulators in other countries to inform various assessments of ecological risk. PMID:25248506

  3. Characterization, Monitoring, and Risk Assessment at the IEA GHG Weyburn-Midale CO2 Monitoring and Storage Project, Saskatchewan, Canada.

    NASA Astrophysics Data System (ADS)

    Ben, R.; Chalaturnyk, R.; Gardner, C.; Hawkes, C.; Johnson, J.; White, D.; Whittaker, S.

    2008-12-01

    In July 2000, a major research project was initiated to study the geological storage of CO2 as part of a 5000 tonnes/day EOR project planned for the Weyburn Field in Saskatchewan, Canada. Major objectives of the IEA GHG Weyburn CO2 monitoring and storage project included: assessing the integrity of the geosphere encompassing the Weyburn oil pool for effective long-term storage of CO2; monitoring the movement of the injected CO2, and assessing the risk of migration of CO2 from the injection zone (approximately 1500 metres depth) to the surface. Over the period 2000-2004, a diverse group of 80+ researchers worked on: geological, geophysical, and hydrogeological characterizations at both the regional (100 km beyond the field) and detailed scale (10 km around the field); conducted time-lapse geophysical surveys; carried out surface and subsurface geochemical surveys; and undertook numerical reservoir simulations. Results of the characterization were used for a performance assessment that concluded the risk of CO2 movement to the biosphere was very small. By September 2007, more than 14 Mtonnes of CO2 had been injected into the Weyburn reservoir, including approximately 3 Mtonnes recycled from oil production. A "Final Phase" research project was initiated (2007- 2011) to contribute to a "Best Practices" guide for long-term CO2 storage in EOR settings. Research objectives include: improving the geoscience characterization; further detailed analysis and data collection on the role of wellbores; additional geochemical and geophysical monitoring activities; and an emphasis on quantitative risk assessments using multiple analysis techniques. In this talk a review of results from Phase I will be presented followed by plans and initial results for the Final Phase.

  4. HUMAN EXPOSURE MODELING TO CHARACTERIZE SOURCE-TO-DOSE RELATIONSHIPS AND REDUCE UNCERTAINTY IN RISK ASSESSMENT

    EPA Science Inventory

    In 1998 EPA's Office of Research and Development (ORD) identified necessary research to strengthen the scientific foundation for human health risk assessment as one of its six high priority areas for long-term research support. In addition, ORD identified three strategic researc...

  5. Characterizing Stressors and Modifiable Health Risk Factors among Homeless Smokers: An Exploratory Pilot Study

    ERIC Educational Resources Information Center

    Kendzor, Darla E.; Reitzel, Lorraine R.; Businelle, Michael S.

    2015-01-01

    This pilot study was conducted to explore the associations between stressors related to homelessness and modifiable health risk factors (poor diet, insufficient physical activity, and overweight/obesity) and to provide direction for future research. Participants (N = 57) were homeless adults enrolled in a smoking cessation program. Analyses were…

  6. Site characterization to support risk assessment of contaminated ground-water- some case studies

    EPA Science Inventory

    In the USA, “risk assessment" generally refers to an evaluation of the impact of a known concentration of a hazardous material in ground water on human health or environmental quality. This presentation is different. It deals with the impact of a spill or release of hazardous m...

  7. Characterizing the Risk Factors Associated With Venous Thromboembolism in Pediatric Patients After Central Venous Line Placement

    PubMed Central

    Eades, Shannan; Turiy, Yuliya

    2015-01-01

    OBJECTIVES: With the apparent increase in venous thromboembolism noted in the pediatric population, it is important to define which children are at risk for clots and to determine optimal preventative therapy. The purpose of this study was to determine the risk factors for venous thromboembolism in pediatric patients with central venous line placement. METHODS: This was an observational, retrospective, case-control study. Control subjects were patients aged 0 to 18 years who had a central venous line placed. Case subjects had a central line and a radiographically confirmed diagnosis of venous thromboembolism. RESULTS: A total of 150 patients were included in the study. Presence of multiple comorbidities, particularly the presence of a congenital heart defect (34.7% case vs. 14.7% control; p < 0.005), was found to put pediatric patients at increased risk for thrombosis. Additionally, the administration of parenteral nutrition through the central line (34.7% case vs. 18.7% control; p = 0.03) and location of the line increased the risk for clot formation. CONCLUSIONS: With increased awareness of central venous line–related thromboembolism, measures should be taken to reduce the number and duration of central line placements, and further studies addressing the need for thromboprophylaxis should be conducted. PMID:26472949

  8. Stochastic fuzzy environmental risk characterization of uncertainty and variability in risk assessments: A case study of polycyclic aromatic hydrocarbons in soil at a petroleum-contaminated site in China.

    PubMed

    Hu, Yan; Wang, Zesen; Wen, Jingya; Li, Yu

    2016-10-01

    Better decisions are made using risk assessment models when uncertainty and variability are explicitly acknowledged. Uncertainty caused by a lack of uniform and scientifically supported environmental quality guidelines and variability in the degree of exposure of environmental systems to contaminants are here incorporated in a stochastic fuzzy environmental risk characterization (SFERC) approach. The approach is based on quotient probability distribution and environmental risk level fuzzy membership function methods. The SFERC framework was used to characterize the environmental risks posed by 16 priority polycyclic aromatic hydrocarbons (PAHs) in soil at a typical petroleum-contaminated site in China. This relied on integrating data from the literature and field and laboratory experiments. The environmental risk levels posed by the PAHs under four risk scenarios were determined using the SFERC approach, using "residential land" and "industrial land" environmental quality guidelines under "loose" and "strict" strictness parameters. The results showed that environmental risks posed by PAHs in soil are primarily caused by oil exploitation, traffic emissions, and coal combustion. The SFERC approach is an effective tool for characterizing uncertainty and variability in environmental risk assessments and for managing contaminated sites. PMID:27232725

  9. Light Water Reactor Sustainability Program Risk Informed Safety Margin Characterization (RISMC) Advanced Test Reactor Demonstration Case Study

    SciTech Connect

    Curtis Smith; David Schwieder; Cherie Phelan; Anh Bui; Paul Bayless

    2012-08-01

    Safety is central to the design, licensing, operation, and economics of Nuclear Power Plants (NPPs). Consequently, the ability to better characterize and quantify safety margin holds the key to improved decision making about LWR design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margins management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. The purpose of the RISMC Pathway R&D is to support plant decisions for risk-informed margins management with the aim to improve economics, reliability, and sustain safety of current NPPs. Goals of the RISMC Pathway are twofold: (1) Develop and demonstrate a risk-assessment method coupled to safety margin quantification that can be used by NPP decision makers as part of their margin recovery strategies. (2) Create an advanced “RISMC toolkit” that enables more accurate representation of NPP safety margin. This report describes the RISMC methodology demonstration where the Advanced Test Reactor (ATR) was used as a test-bed for purposes of determining safety margins. As part of the demonstration, we describe how both the thermal-hydraulics and probabilistic safety calculations are integrated and used to quantify margin management strategies.

  10. Polybrominated diphenyl ethers (PBDEs) concentration in soil from San Luis Potosi, Mexico: levels and ecological and human health risk characterization.

    PubMed

    Pérez-Vázquez, Francisco J; Orta-García, Sandra T; Ochoa-Martínez, Ángeles C; Pruneda-Álvarez, Lucia G; Ruiz-Vera, Tania; Jiménez-Avalos, Jorge Armando; González-Palomo, Ana K; Pérez-Maldonado, Iván N

    2016-01-01

    The aim of this study was to assess the levels of polybrominated diphenyl ethers (PBDEs) in soils from the city of San Luis Potosi in Mexico and perform an ecological and human health risk characterization. In order to confirm the presence of PBDEs, outdoor surface soil samples were collected and the concentrations of PBDEs in urban, industrial, agricultural, and brick kiln industry areas were determined. The mean total PBDEs levels obtained in the study sites were 25.0 ± 39.5 μg/kg (geometric mean ± standard deviation) in the brick kiln industry zone; 34.5 ± 36.0 μg/kg in the urban zone; 8.00 ± 7.10 μg/kg in the industrial zone and 16.6 ± 15.3 μg/kg in the agricultural zone. The ecological and human health risk characterization showed relatively low-hazard quotient values. However, the moderately high PBDEs levels found in soils highlight the necessity to establish a systematic monitoring process for PBDEs in environmental and biological samples. PMID:26566197

  11. Prototype Near-Field/GIS Model for Sequestered-CO2 Risk Characterization and Management

    SciTech Connect

    Bogen, K T; Homann, S G; Gouveia, F J; Neher, L A

    2006-02-10

    Detecting unmapped abandoned wells thus remains a major carbon sequestration (CS) technology gap. Many (>10{sup 5}) abandoned wells are thought to lie in potential sequestration sites. For such wells, risk analysis to date has focused on aggregate long-term future impacts of seepage at rates < or << {approx}1 g m{sup 2} d{sup -1} on storage goals as sequestered plumes encroach upon wells with assumed distributions of seal ineffectiveness (Oldenburg and Unger, 2003; Saripali et al. 2003; Celia, 2005). However, unmapped abandoned wells include an unknown number without any effective seal at all, venting through which may dominate CO{sub 2}-loss scenarios. A model of such a well is Crystal Geyser (CG), a prospective oil well abandoned in the 1930s with no barrier installed after it encountered a natural CO{sub 2} reservoir rather than oil (Baer and Rigby, 1978; Rinehart, 1980). CG demonstrates how an unimpeded conduit to the surface now regularly vents from 10{sup 3} to >10{sup 4} kg of CO{sub 2} gas to the terrestrial surface (Figure 1). Unique field data recently gathered from Crystal Geyser (CG) in Utah (Gouveia et al. 2005) confirm that, although resulting surface CO{sub 2} concentrations resulting from CG-like eruptions would likely be safe in general, they could accumulate to pose lethal hazards under relatively rare meteorological and topographic (MT) conditions. This source of foreseeable risk needs to be managed if carbon sequestration is to be publicly accepted. To address this concern, we used CG field data to estimate the source term for a prototype model that identifies zones at relatively highly elevated risk for sequestered-CO{sub 2} casualties. Such a model could be applied both to design and comply with future regulatory requirements to survey high-risk zones in each proposed sequestration site for improperly sealed wells.

  12. Characterization and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in urban atmospheric Particulate of Tehran, Iran.

    PubMed

    Hoseini, Mohammad; Yunesian, Masud; Nabizadeh, Ramin; Yaghmaeian, Kamyar; Ahmadkhaniha, Reza; Rastkari, Noushin; Parmy, Saeid; Faridi, Sasan; Rafiee, Ata; Naddafi, Kazem

    2016-01-01

    In this study, atmospheric concentrations of particulate-bound polycyclic aromatic hydrocarbons (PAHs) in Tehran megacity were determined to investigate the concentration, distribution, and sources of PAHs in PM10. The health risk from exposure to airborne BaPeq through inhalation pathway was also assessed. Toxic equivalency factors (TEFs) approach was used for quantitative risk estimate, and incremental lifetime cancer risk (ILCR) was calculated. PM10 samples were collected at ten sampling locations during the summer 2013 and winter 2014 by using two independent methods of field sampling. The PM10 concentration in winter (89.55 ± 15.56 μg m(-3)) was 1.19 times higher than that in summer (75.42 ± 14.93 μg m(-3)). Sixteen PAHs were measured with the total average concentrations of PAHs ranged from 56.98 ± 15.91 to 110.35 ± 57.31 ng m(-3) in summer and from 125.87 ± 79.02 to 171.25 ± 73.94 ng m(-3) in winter which were much higher than concentrations measured in most similar studies conducted around the world. Molecular diagnostic ratios were used to identify PAH emission sources. The results indicated that gasoline-driven vehicles are the major sources of PAHs in the study area. Risk analysis showed that the mean and 90 % probability estimated inhalation ILCRs were 7.85 × 10(-6) and 16.78 × 10(-6), respectively. Results of a sensitivity analysis indicated that BaP concentration and cancer slope factor (CSF) contributed most to effect on ILCR mean. PMID:26400241

  13. Replacement of HEPA Filters at the LANL CMR Facility: Risks Reduced by Comprehensive Waste Characterization

    SciTech Connect

    Corpion, J.; Barr, A.; Martinez, P.; Bader, M.

    2002-02-28

    In March 2001, the Los Alamos National Laboratory (LANL) completed the replacement of 720 radioactively contaminated HEPA filters for $5.7M. This project was completed five months ahead of schedule and $6.0M under budget with no worker injuries or contaminations. Numerous health and safety, environmental, and waste disposal problems were overcome, including having to perform work in a radioactively contaminated work environment, that was also contaminated with perchlorates (potential explosive). High waste disposal costs were also an issue. A project risk analysis and government cost estimate determined that the cost of performing the work would be $11.8M. To reduce risk, a $1.2M comprehensive condition assessment was performed to determine the degree of toxic and radioactive contamination trapped on the HEPA filters; and to determine whether explosive concentrations of perchlorates were present. Workers from LANL and personnel from Waldheim International of Knoxville, TN collected hundreds of samples wearing personnel protective gear against radioactive, toxic, and explosive hazards. LANL also funded research at the New Mexico Institute of Mining and Technology to determine the explosivity of perchlorates. The data acquired from the condition assessment showed that toxic metals, toxic organic compounds, and explosive concentrations of perchlorates were absent. The data also showed that the extent of actinide metal contamination was less than expected, reducing the potential of transuranic waste generation by 50%. Consequently, $4.2M in cost savings and $1.8M in risk reduction were realized by increased worker productivity and waste segregation.

  14. Replacement of HEPA Filters at the LANL CMR Facility : risk reduced by comprehensive waste characterization

    SciTech Connect

    Corpion, J. C.

    2002-01-01

    In March 2001, the Los Alamos National Laboratory (LANL) completed the replacement of 720 radioactively contaminated HEPA filters for $5.7M. This project was completed five months ahead of schedule and $6.0M under budget with no worker injuries or contaminations. Numerous health and safety, environmental, and waste disposal problems were overcome, including having to perform work in a radioactively contaminated work environment, that was also contaminated with perchlorates (potential explosive). High waste disposal costs were also an issue. A project risk analysis and government cost estimate determined that the cost of performing the work would be $11.8M. To reduce risk, a $1.2M comprehensive condition assessment was performed to determine the degree of toxic and radioactive contamination trapped on the HEPA filters; and to determine whether explosive concentrations of perchlorates were present. Workers from LANL and personnel from Waldheim International of Knoxville, TN collected hundreds of samples wearing personnel protective gear against radioactive, toxic, and explosive hazards. LANL also funded research at the New Mexico Institute of Mining and Technology to determine the explosivity of perchlorates. The data acquired from the condition assessment showed that toxic metals, toxic organic compounds, and explosive concentrations of perchlorates were absent. The data also showed that the extent of actinide metal contamination was less than expected, reducing the potential of transuranic waste generation by 50%. Consequently, $4.2M in cost savings and $1.8M in risk reduction were realized by increased worker productivity and waste segregation.

  15. Lead bioaccessibility in food web intermediates and the influence on ecological risk characterization.

    PubMed

    Kaufman, Claire A; Bennett, Joseph R; Koch, Iris; Reimer, Kenneth J

    2007-08-15

    Models simulating gastric conditions of mammalian (eastern cottontail, Sylvilagus floridanus; short-tailed shrew, Blarina brevicauda) and avian (American robin, Turdus migratorius) receptors were used to investigate the proportion of lead (Pb) mobilized into the digestive juices (the bioaccessible fraction) from soil, earthworms, and vegetation collected at a rifle and pistol (RP) range in eastern Ontario, Canada. Pb concentrations averaged 5044 mg kg(-1) in RP range surface soils, 727 mg kg(-1) in earthworm tissue, and 2945 mg kg(-1) in unwashed vegetation. For mammalian gastric models, the bioaccessible fraction of Pb in soils was 66 +/- 22%, in earthworm tissue was 77 +/- 14%, and in unwashed vegetation was 50 +/- 37%. For the avian gastric model, the bioaccessible fraction of Pb in soil was 53 +/- 43% and in earthworm tissue was 73 +/- 13%. The incorporation of soil and food web intermediate bioaccessibility data into standard risk calculations resulted in predicted risk being reduced for all receptors. The inclusion of bioaccessibility during ecological risk assessment affords a more realistic estimate of contaminant exposure, and is a valuable tool for use in contaminated sites management. PMID:17874804

  16. Modeling of Near-Surface Leakage and Seepage of CO2 for Risk Characterization

    SciTech Connect

    Oldenburg, Curtis M.; Unger, Andre A.J.

    2004-02-18

    The injection of carbon dioxide (CO2) into deep geologic carbon sequestration sites entails risk that CO2 will leak away from the primary storage formation and migrate upwards to the unsaturated zone from which it can seep out of the ground. We have developed a coupled modeling framework called T2CA for simulating CO2 leakage and seepage in the subsurface and in the atmospheric surface layer. The results of model simulations can be used to calculate the two key health, safety, and environmental (HSE) risk drivers, namely CO2 seepage flux and nearsurface CO2 concentrations. Sensitivity studies for a subsurface system with a thick unsaturated zone show limited leakage attenuation resulting in correspondingly large CO2 concentrations in the shallow subsurface. Large CO2 concentrations in the shallow subsurface present a risk to plant and tree roots, and to humans and other animals in subsurface structures such as basements or utility vaults. Whereas CO2 concentrations in the subsurface can be high, surfacelayer winds reduce CO2 concentrations to low levels for the fluxes investigated. We recommend more verification and case studies be carried out with T2CA, along with the development of extensions to handle additional scenarios such as calm conditions, topographic effects, and catastrophic surface-layer discharge events.

  17. Oxidative stress as a risk factor for osteoporosis in elderly Mexicans as characterized by antioxidant enzymes

    PubMed Central

    Sánchez-Rodríguez, Martha A; Ruiz-Ramos, Mirna; Correa-Muñoz, Elsa; Mendoza-Núñez, Víctor Manuel

    2007-01-01

    Background Oxidative stress (OxS) has recently been linked with osteoporosis; however, we do not know the influence of OxS as an independent risk factor for this disease. Methods We conducted a case-control study in 94 subjects ≥60 years of age, 50 healthy and 44 with osteoporosis. We measured total antioxidant status, plasma lipid peroxides, antioxidant activity of superoxide dismutase and glutathione peroxidase (GPx), and calculated the SOD/GPx ratio. Bone mineral density was obtained at the peripheral DXA in calcaneus using a portable Norland Apollo Densitometer®. Osteoporosis was considered when subjects had a BMD of 2.5 standard deviations or more below the mean value for young adults. Results GPx antioxidant activity was significantly lower in the group of subjects with osteoporosis in comparison with the group of healthy subjects (p < 0.01); in addition, the SOD/GPx ratio was significantly higher in the group of individuals with osteoporosis (p < 0.05). In logistic regression analysis, we found OxS to be an independent risk factor for osteoporosis (odds ratio [OR] = 2.79; 95% confidence interval [95% CI] = 1.08–7.23; p = 0.034). Conclusion Our findings suggest that OxS is an independent risk factor for osteoporosis linked to increase of SOD/GPx ratio. PMID:18088440

  18. Characterization of the nuclear localization signal of high risk HPV16 E2 protein

    SciTech Connect

    Klucevsek, Kristin; Wertz, Mary; Lucchi, John; Leszczynski, Anna; Moroianu, Junona . E-mail: moroianu@bc.edu

    2007-03-30

    The E2 protein of high risk human papillomavirus type 16 (HPV16) contains an amino-terminal (N) domain, a hinge (H) region and a carboxyl-terminal (C) DNA-binding domain. Using enhanced green fluorescent protein (EGFP) fusions with full length E2 and E2 domains in transfection assays in HeLa cells, we found that the C domain is responsible for the nuclear localization of E2 in vivo, whereas the N and H domains do not contain additional nuclear localization signals (NLSs). Deletion analysis of EGFP-E2 and EGFP-cE2 determined that the C domain contains an {alpha} helix cNLS that overlaps with the DNA-binding region. Mutational analysis revealed that the arginine and lysine residues in this cNLS are essential for nuclear localization of HPV16 E2. Interestingly, these basic amino acid residues are well conserved among the E2 proteins of BPV-1 and some high risk HPV types but not in the low risk HPV types, suggesting that there are differences between the NLSs and corresponding nuclear import pathways between these E2 proteins.

  19. Characterization of pharmaceutically active compounds in Dongting Lake, China: Occurrence, chiral profiling and environmental risk.

    PubMed

    Ma, Ruixue; Wang, Bin; Lu, Shaoyong; Zhang, Yizhe; Yin, Lina; Huang, Jun; Deng, Shubo; Wang, Yujue; Yu, Gang

    2016-07-01

    Twenty commonly used pharmaceuticals including eight chiral drugs were investigated in Dongting Lake, China. The contamination level was relatively low on a global scale. Twelve pharmaceuticals were identified. The most abundant compound was caffeine followed by diclofenac, DEET, mefenamic acid, fluoxetine, ibuprofen and carbamazepine with mean concentrations from 2.0 to 80.8ngL(-1). Concentrations between East and West Dongting Lake showed spatial difference, with the West Dongting Lake less polluted. The relatively high ratio of caffeine versus carbamazepine (over 50) may indicate there was possible direct discharge of domestic wastewater into the lake. This is the first study presenting a survey allowing for comprehensive analysis of multiclass achiral and chiral pharmaceuticals including beta-blockers, antidepressants and anti-inflammatory drugs in freshwater lake. The enantiomeric compositions presented racemic to weakly enantioselective, with the highest enantiomeric fraction (EF) of 0.63 for fluoxetine. Meanwhile, venlafaxine was identified and evaluated the environment risk in surface water in China for the first time. The results of risk assessment suggested that fluoxetine, venlafaxine and diclofenac acid might pose a significant risk to aquatic organisms in Dongting Lake. The resulting data will be useful to enrich the research of emerging pollutants in freshwater lake and stereochemistry for environment investigations. PMID:27016674

  20. Characterization and health risk assessment of VOCs in occupational environments in Buenos Aires, Argentina

    NASA Astrophysics Data System (ADS)

    Colman Lerner, J. E.; Sanchez, E. Y.; Sambeth, J. E.; Porta, A. A.

    2012-08-01

    To detect volatile organic compounds (VOCs) in indoor air in small enterprises in La Plata city and surrounding areas, sampling was conducted using passive diffusion monitors (3M-3500) and analysis of the samples were performed byCG-FID. Analytic methodology was optimized for 23 VOCs (n-alkanes, cycloalkanes, aromatic and chlorinated compounds, ketones and terpenes compounds) by determining the recovery factor and detection limit for each analyte. Different recovery values were obtained by desorbing with a mixture of dichloromethane: methanol (50:50), with a standard deviation lower than 5%. Enterprise analyzed included chemical analysis laboratories, sewing workrooms, electromechanical repair and car painting centers, take away food shops, and a photocopy center. The highest levels of VOCs were found to be in electromechanical repair and car painting centers (hexane, BTEX, CHCl3, CCl4) followed by chemical analysis laboratories and sewing workrooms. Cancer and noncancer risks were assessed using conventional approaches (HQ and LCR, US EPA) using the benzene, trichloroethylene, chloroform for cancer risk, and toluene, xylene and n-hexane, for noncancer risks as markers. The results showed different LCR for benzene and trichloroethylene between the different indoor environments analyzed (electromechanical repair and car painting center ≫ others) and chloroform (laboratory > others), but comparing with the results obtained by other research, are in similar order of magnitude for equivalents activities. Similar finding were founded for HQ. Comparing these results with the worker protection legislation the electromechanical repair and car painting center and chemical analysis laboratories are close to the limits advised by OSHA and ACGIH. These facts show the importance of the use of abatement technologies for the complete reduction of VOCs levels, to mitigate their impact in the worker's health and their venting to the atmosphere.

  1. Hazard identification and risk characterization of bisphenols A, F and AF to aquatic organisms.

    PubMed

    Tišler, Tatjana; Krel, Alja; Gerželj, Urška; Erjavec, Boštjan; Dolenc, Marija Sollner; Pintar, Albin

    2016-05-01

    Production of bisphenol A (BPA) analogues such as bisphenol F (BPF) and bisphenol AF (BPAF) has recently increased, due to clear evidence of adverse effects of BPA on humans and wildlife. Bisphenols (BPs) have already been released into aquatic environment without previous available information about potential adverse effects of BPs and their potential risk to aquatic ecosystems. In this study, lethal and sublethal effects of BPF and BPAF to bacteria, algae, crustacea and fish embryos were investigated and the results were compared to the adverse effects obtained for BPA. We found that BPAF was the most toxic compound to Daphnia magna, Danio rerio and Desmodesmus subspicatus; the lowest 72 h EC50 (median effective concentration) and 21 d NOEC (no observed effect concentration) values were determined at 2.2 mg/L regarding zebrafish hatching success and 0.23 mg/L of BPAF obtained for growth and reproduction of water fleas, respectively. In most cases, BPA was more toxic to D. magna, D. rerio and D. subspicatus in comparison to BPF, but pigmentation of zebrafish embryos after 48 h of exposure and reproduction of water fleas after 21-day D. magna reproductive test exposure to BPF were much more impaired. Risk quotients (measured environmental concentration/21 d NOEC) showed that BPA, BPF and BPAF are recently not chronically hazardous to the survival, reproduction and growth of water fleas in surface waters. On the other hand, we importantly show that currently present BPAF concentrations in surface waters could cause a potential ecological risk to aquatic organisms. In the near future, higher concentrations of BPF and BPAF in surface waters are anticipated and for this reason further testing using test systems with various aquatic species and endpoints are needed to provide additional information about toxic impacts of BPF and BPAF on aquatic biota. PMID:26957022

  2. Characterization of Mercury and Its Risk in Nelson’s, Saltmarsh, and Seaside Sparrows

    PubMed Central

    Winder, Virginia L.

    2012-01-01

    Background Nelson’s, Saltmarsh, and Seaside Sparrows (Ammodramus nelsoni, A. caudacutus, and A. maritimus, respectively) depend on marsh and wetland habitats – ecosystems in which mercury (Hg) bioavailability is notoriously high. The purpose of the present study was to address the potential impact of Hg on these species using first primary and breast feathers as non-destructive biomonitoring tools. Methods and Principal Findings Feathers were sampled from wintering sparrows in North Carolina salt marshes (2006–2010). Feather Hg data were used in three risk analysis components (1) Threshold Component – examined feather Hg with regard to published negative effects thresholds; (2) Hg Dynamics Component – examined Hg in sparrows captured multiple times; and (3) Capture Frequency and Survival Component – tested for links between Hg and return frequency and survival. Threshold Component analyses indicated that Hg concentrations in 42–77% of sampled individuals (breast feather n = 879; first primary feather n = 663) were within the range associated with decreased reproduction in other avian species. Hg Dynamics Component analyses demonstrated that Hg increased between first and second captures for Nelson’s (n = 9) and Seaside Sparrows (n = 23). Capture Frequency and Survival Component analyses detected a negative relationship between Hg and capture frequency in Nelson’s Sparrows (n = 315). However, MARK models detected no effect of Hg on apparent survival in any species. Conclusion and Significance This study indicates that current Hg exposure places a considerable proportion of each population at risk. In particular, 52% of all sampled Saltmarsh Sparrows exhibited first primary feather Hg concentrations exceeding those associated with a >60% reduction in reproductive success in other species. This study reports evidence for net annual bioaccumulation, indicating an increased risk in older individuals. These data can be used to inform

  3. Characterization and risk assessment of PAH-contaminated river sediment by using advanced multivariate methods.

    PubMed

    Wang, Yeuh-Bin; Liu, Chen-Wuing; Kao, Yu-Hsuan; Jang, Cheng-Shin

    2015-08-15

    This study applied advanced multivariate methods and risk assessment to evaluate the characteristics of polycyclic aromatic hydrocarbons (PAHs) in the sediment of the severely polluted Erjen River in Taiwan. High-molecular-weight PAHs (HPAHs) dominated in the rainy season. The ecological risk of PAHs in the sediment was low, whereas the total health risk through ingestion and dermal contact was considerably high. The SOM (self-organizing map) analysis clustered the datasets of PAH-contaminated sediment into five groups with similar concentration levels. Factor analysis identified major factors, namely coal combustion, traffic, petrogenic, and petrochemical industry factors, accounting for 88.67% of the variance in the original datasets. The major tributary and the downstream of the river were identified as PAH-contamination hotspots. The PMF (positive matrix factorization) was combined with toxicity assessment to estimate the possible apportionment of sources and the associated toxicity. Spills of petroleum-related products, vehicle exhaust, coal combustion, and exhaust from a petrochemical industry complex constituted respectively 12%, 6%, 74%, and 86% of PAHs in the sediment, but contributed respectively 7%, 15%, 22%, and 56% of toxicity posed by PAHs in the sediment. To improve the sediment quality, best management practices should be adopted to eliminate nonpoint sources of PAHs flushed by storm water into the major tributary and the downstream of the Erjen River. The proposed methodologies and results provide useful information on remediating river PAH-contaminated sediment and may be applicable to other basins with similar properties that are experiencing resembled river environmental issues. PMID:25889545

  4. Glycoalkaloid Levels in Solanum Microdontum and S. Jamesii Accessions: A Consideration in Parental Selection When Breeding for High Antioxidant Activity in Potato

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antioxidants are useful in reducing risk of several diseases associated with free radicals. While potatoes are not as high in antioxidants as fruits, the fact that large quantities of potatoes are consumed (~130 lbs per capita) suggests that any increase in tuber antioxidants would greatly benefit h...

  5. Wind Characterization for the Assessment of Collision Risk During Flight Level Changes

    NASA Technical Reports Server (NTRS)

    Carreno, Victor; Chartrand, Ryan

    2009-01-01

    A model of vertical wind gradient is presented based on National Oceanic and Atmospheric Administration (NOAA) wind data. The objective is to have an accurate representation of wind to be used in Collision Risk Models (CRM) of aircraft procedures. Depending on how an aircraft procedure is defined, wind and the different characteristics of the wind will have a more severe or less severe impact on distances between aircraft. For the In-Trail Procedure, the non-linearity of the vertical wind gradient has the greatest impact on longitudinal distance. The analysis in this paper extracts standard deviation, mean, maximum, and linearity characteristics from the NOAA data.

  6. Risk factors associated with endometriosis: importance of study population for characterizing disease in the ENDO Study

    PubMed Central

    Peterson, C. Matthew; Johnstone, Erica B.; Hammoud, Ahmad O.; Stanford, Joseph B.; Varner, Michael W.; Kennedy, Anne; Chen, Zhen; Sun, Liping; Fujimoto, Victor Y.; Hediger, Mary L.; Buck Louis, Germaine M.

    2014-01-01

    OBJECTIVE We sought to identify risk factors for endometriosis and their consistency across study populations in the Endometriosis: Natural History, Diagnosis, and Outcomes (ENDO) Study. STUDY DESIGN In this prospective matched, exposure cohort design, 495 women aged 18–44 years undergoing pelvic surgery (exposed to surgery, operative cohort) were compared to an age- and residence-matched population cohort of 131 women (unexposed to surgery, populationcohort). Endometriosis was diagnosed visually at laparoscopy/laparotomy or by pelvic magnetic resonance imaging in the operative and population cohorts, respectively. Logistic regression estimated the adjusted odds ratios (AORs) and 95% confidence intervals (CIs) for each cohort. RESULTS The incidence of visualized endometriosis was 40% in the operative cohort (11.8% stage 3–4 by revised criteria from the American Society for Reproductive Medicine), and 11% stage 3–4 in the population cohort by magnetic resonance imaging. An infertility history increased the odds of an endometriosis diagnosis in both the operative (AOR, 2.43; 95% CI, 1.57–3.76) and population (AOR, 7.91; 95% CI, 1.69–37.2) cohorts. In the operative cohort only, dysmenorrhea (AOR, 2.46; 95% CI, 1.28–4.72) and pelvic pain (AOR, 3.67; 95% CI, 2.44–5.50) increased the odds of diagnosis, while gravidity (AOR, 0.49; 95% CI, 0.32–0.75), parity (AOR, 0.42; 95% CI, 0.28–0.64), and body mass index (AOR, 0.95; 95% CI, 0.93–0.98) decreased the odds of diagnosis. In all sensitivity analyses for different diagnostic subgroups, infertility history remained a strong risk factor. CONCLUSION An infertility history was a consistent risk factor for endometriosis in both the operative and population cohorts of the ENDO Study. Additionally, identified risk factors for endometriosis vary based upon cohort selection and diagnostic accuracy. Finally, endometriosis in the population may be more common than recognized. PMID:23454253

  7. Characterizing the impacts of water resources infrastructure, humans, and hydrologic nonstationarity on changes in flood risk across the Himalaya region

    NASA Astrophysics Data System (ADS)

    Tullos, D. D.

    2014-12-01

    As flood control infrastructure reaches its design life, and climate change, population growth, and urban migration increase flood risk, the historical paradigm of store-then-release floodwaters behind rigid infrastructure is of decreasing physical and socioeconomic value. Instead, a new paradigm of sustainable flood management is emerging, which can be framed in the context of three elements that can contribute to and/or mitigate flood risk: 1) water resources infrastructure, 2) policies and socioeconomics, and 3) changing climates and land use. In this presentation, I present the results of analysis on the role of these three elements in contributing to flood risk of the Sutlej River (India) and the Koshi River (Nepal) basins for six historical flood events. The Himalaya region was selected based on the a) increasing intensity of monsoonal rains, b) increasing prevalence of glacial lake outburst floods, c) water resources management that achieves short-term development goals but lacks long-term sustainability, and d) other socio-economic, environmental, and geopolitical factors. I develop and apply a flood risk management framework that is based on metrics for characterizing the losses associated with the three elements contributing to major floods in the Himalaya region. Derived from a variety of data sources, results highlight how, across different hydrogeologic settings and various flood magnitudes, the largest influences on high flood losses are associated with inflexible water resources infrastructure and inappropriate development and flood management policies. Particularly for the most destructive events, which are generally associated with landslides and other natural hazards in this region, the effectiveness of some types of traditional and inflexible flood management infrastructure, including large dams and levees, is limited. As opposed to the probability of a particular flood event, findings illustrate the importance of the damages side of the flood

  8. Emissions of particulate-bound elements from stationary diesel engine: Characterization and risk assessment

    NASA Astrophysics Data System (ADS)

    Betha, Raghu; Balasubramanian, Rajasekhar

    2011-09-01

    There has been an increasing concern about the emissions of airborne particulate matter (PM) from diesel engines because of their close association with adverse health and environmental impacts. Among the alternative fuels being considered, biodiesel made by the transesterification of waste cooking oil has received wide attention in recent years because of its low cost and the added advantage of reducing waste oil disposal. This study was conducted to make a comparative evaluation of the particulate-bound elements emitted from ultra low sulphur diesel (ULSD) and waste cooking oil-derived biodiesel (B100) and a blend of both the fuels (B50). It was observed that the PM mass concentrations were reduced by about 36% when B100 was used. Crustal elements such as Mg, K and Al were found to be in higher concentrations compared to other elements emitted from both B100 and ULSD. Zn, Cr, Cu, Fe, Ni, Mg, Ba, K were found to be higher in the biodiesel exhaust while Co, Pb, Mn, Cd, Sr, and As were found to be higher in the ULSD exhaust. To evaluate the potential health risk due to inhalation of PM emitted from diesel engines running on ULSD and B100, health risk estimates based on exposure and dose-response assessments of particulate-bound elements were calculated assuming exposure for 24 h. The findings indicate that the exposure to PM of the B100 exhaust is relatively more hazardous and may pose adverse health effects compared to ULSD.

  9. Characterizing distribution, sources, and potential health risk of polybrominated diphenyl ethers (PBDEs) in office environment.

    PubMed

    Li, Yue; Chen, Ling; Wen, Zhi-Hao; Duan, Yan-Ping; Lu, Zhi-Bo; Meng, Xiang-Zhou; Zhang, Wen

    2015-03-01

    This study evaluated the levels and spatial distribution of PBDEs in 9 typical offices in Shanghai, China through the sample analysis of air and settled dust (floor dust, desktop dust and dust in computer case). PBDEs in air ranged from 93 to 322 pg/m(3), while the PBDEs levels in dust varied from 247 to 3.3 × 10(4) ng/g. Spatial variability of PBDEs in office dust was evident and likely influenced by air exchange and the use of electronic devices. A significant positive linear correlation was observed between the power usage rate and PBDE levels in both office air (R(2) = 0.81) and settled dust (R(2) = 0.94). The PBDEs exposure via inhalation and dust ingestion were both analyzed to estimate the life-time cancer risk, which is 1.34 × 10(-22) to 7.16 × 10(-22), significantly lower than the threshold level (10(-6)). Non-cancer risk indicated by the hazard index (<1) is also low in current exposure conditions. PMID:25549864

  10. Equipment characterization to mitigate risks during transfers of cell culture manufacturing processes.

    PubMed

    Sieblist, Christian; Jenzsch, Marco; Pohlscheidt, Michael

    2016-08-01

    The production of monoclonal antibodies by mammalian cell culture in bioreactors up to 25,000 L is state of the art technology in the biotech industry. During the lifecycle of a product, several scale up activities and technology transfers are typically executed to enable the supply chain strategy of a global pharmaceutical company. Given the sensitivity of mammalian cells to physicochemical culture conditions, process and equipment knowledge are critical to avoid impacts on timelines, product quantity and quality. Especially, the fluid dynamics of large scale bioreactors versus small scale models need to be described, and similarity demonstrated, in light of the Quality by Design approach promoted by the FDA. This approach comprises an associated design space which is established during process characterization and validation in bench scale bioreactors. Therefore the establishment of predictive models and simulation tools for major operating conditions of stirred vessels (mixing, mass transfer, and shear force.), based on fundamental engineering principles, have experienced a renaissance in the recent years. This work illustrates the systematic characterization of a large variety of bioreactor designs deployed in a global manufacturing network ranging from small bench scale equipment to large scale production equipment (25,000 L). Several traditional methods to determine power input, mixing, mass transfer and shear force have been used to create a data base and identify differences for various impeller types and configurations in operating ranges typically applied in cell culture processes at manufacturing scale. In addition, extrapolation of different empirical models, e.g. Cooke et al. (Paper presented at the proceedings of the 2nd international conference of bioreactor fluid dynamics, Cranfield, UK, 1988), have been assessed for their validity in these operational ranges. Results for selected designs are shown and serve as examples of structured

  11. Characterization of the Vaginal Microbiota among Sexual Risk Behavior Groups of Women with Bacterial Vaginosis

    PubMed Central

    Muzny, Christina A.; Sunesara, Imran R.; Kumar, Ranjit; Mena, Leandro A.; Griswold, Michael E.; Martin, David H.; Lefkowitz, Elliot J.; Schwebke, Jane R.

    2013-01-01

    Background The pathogenesis of bacterial vaginosis (BV) remains elusive. BV may be more common among women who have sex with women (WSW). The objective of this study was to use 454 pyrosequencing to investigate the vaginal microbiome of WSW, women who have sex with women and men (WSWM), and women who have sex with men (WSM) with BV to determine if there are differences in organism composition between groups that may inform new hypotheses regarding the pathogenesis of BV. Methods Vaginal swab specimens from eligible women with BV at the Mississippi State Department of Health STD Clinic were used. After DNA extraction, 454 pyrosequencing of PCR-amplified 16S rRNA gene sequences was performed. Sequence data was classified using the Ribosomal Database Program classifer. Complete linkage clustering analysis was performed to compare bacterial community composition among samples. Differences in operational taxonomic units with an abundance of ≥2% between risk behavior groups were determined. Alpha and beta diversity were measured using Shannon’s Index implemented in QIIME and Unifrac analysis, respectively. Results 33 WSW, 35 WSWM, and 44 WSM were included. The vaginal bacterial communities of all women clustered into four taxonomic groups with the dominant taxonomic group in each being Lactobacillus, Lachnospiraceae, Prevotella, and Sneathia. Regarding differences in organism composition between risk behavior groups, the abundance of Atopobium (relative ratio (RR)=0.24; 95%CI 0.11-0.54) and Parvimonas (RR=0.33; 95%CI 0.11-0.93) were significantly lower in WSW than WSM, the abundance of Prevotella was significantly higher in WSW than WSWM (RR=1.77; 95%CI 1.10-2.86), and the abundance of Atopobium (RR=0.41; 95%CI 0.18-0.88) was significantly lower in WSWM than WSM. Overall, WSM had the highest diversity of bacterial taxa. Conclusion The microbiology of BV among women in different risk behavior groups is heterogeneous. WSM in this study had the highest diversity of

  12. Development of a drone equipped with optimized sensors for nuclear and radiological risk characterization

    SciTech Connect

    Boudergui, K.; Carrel, F.; Domenech, T.; Guenard, N.; Poli, J. P.; Ravet, A.; Schoepff, V.; Woo, R.

    2011-07-01

    The MOBISIC project, funded by the Systematic Paris-Region cluster, is being developed in the context of local crisis (attack bombing in urban environment, in confined space such as an underground train tunnel etc.) or specific event securing (soccer world cup, political meeting etc.). It consists in conceiving, developing and experimenting a mobile, modular ('plug and play') and multi-sensors securing system. In this project, CEA LIST has suggested different solutions for nuclear risks detection and identification. It results in embedding a CZT sensor and a gamma camera in an indoor drone. This article first presents the different modifications carried out on the UAV and different sensors, and focuses then on the experimental performances. (authors)

  13. Characterization of Eyjafjallajökull volcanic ash particles and a protocol for rapid risk assessment

    PubMed Central

    Gislason, S. R.; Hassenkam, T.; Nedel, S.; Bovet, N.; Eiriksdottir, E. S.; Alfredsson, H. A.; Hem, C. P.; Balogh, Z. I.; Dideriksen, K.; Oskarsson, N.; Sigfusson, B.; Larsen, G.; Stipp, S. L. S.

    2011-01-01

    On April 14, 2010, when meltwaters from the Eyjafjallajökull glacier mixed with hot magma, an explosive eruption sent unusually fine-grained ash into the jet stream. It quickly dispersed over Europe. Previous airplane encounters with ash resulted in sandblasted windows and particles melted inside jet engines, causing them to fail. Therefore, air traffic was grounded for several days. Concerns also arose about health risks from fallout, because ash can transport acids as well as toxic compounds, such as fluoride, aluminum, and arsenic. Studies on ash are usually made on material collected far from the source, where it could have mixed with other atmospheric particles, or after exposure to water as rain or fog, which would alter surface composition. For this study, a unique set of dry ash samples was collected immediately after the explosive event and compared with fresh ash from a later, more typical eruption. Using nanotechniques, custom-designed for studying natural materials, we explored the physical and chemical nature of the ash to determine if fears about health and safety were justified and we developed a protocol that will serve for assessing risks during a future event. On single particles, we identified the composition of nanometer scale salt coatings and measured the mass of adsorbed salts with picogram resolution. The particles of explosive ash that reached Europe in the jet stream were especially sharp and abrasive over their entire size range, from submillimeter to tens of nanometers. Edges remained sharp even after a couple of weeks of abrasion in stirred water suspensions. PMID:21518890

  14. Improved Sampling Algorithms in the Risk-Informed Safety Margin Characterization Toolkit

    SciTech Connect

    Mandelli, Diego; Smith, Curtis Lee; Alfonsi, Andrea; Rabiti, Cristian; Cogliati, Joshua Joseph

    2015-09-01

    The RISMC approach is developing advanced set of methodologies and algorithms in order to perform Probabilistic Risk Analyses (PRAs). In contrast to classical PRA methods, which are based on Event-Tree and Fault-Tree methods, the RISMC approach largely employs system simulator codes applied to stochastic analysis tools. The basic idea is to randomly perturb (by employing sampling algorithms) timing and sequencing of events and internal parameters of the system codes (i.e., uncertain parameters) in order to estimate stochastic parameters such as core damage probability. This approach applied to complex systems such as nuclear power plants requires to perform a series of computationally expensive simulation runs given a large set of uncertain parameters. These types of analysis are affected by two issues. Firstly, the space of the possible solutions (a.k.a., the issue space or the response surface) can be sampled only very sparsely, and this precludes the ability to fully analyze the impact of uncertainties on the system dynamics. Secondly, large amounts of data are generated and tools to generate knowledge from such data sets are not yet available. This report focuses on the first issue and in particular employs novel methods that optimize the information generated by the sampling process by sampling unexplored and risk-significant regions of the issue space: adaptive (smart) sampling algorithms. They infer system response from surrogate models constructed from existing samples and predict the most relevant location of the next sample. It is therefore possible to understand features of the issue space with a small number of carefully selected samples. In this report, we will present how it is possible to perform adaptive sampling using the RISMC toolkit and highlight the advantages compared to more classical sampling approaches such Monte-Carlo. We will employ RAVEN to perform such statistical analyses using both analytical cases but also another RISMC code: RELAP-7.

  15. Characterization of Eyjafjallajokull volcanic ash particles and a protocol for rapid risk assessment.

    PubMed

    Gislason, S R; Hassenkam, T; Nedel, S; Bovet, N; Eiriksdottir, E S; Alfredsson, H A; Hem, C P; Balogh, Z I; Dideriksen, K; Oskarsson, N; Sigfusson, B; Larsen, G; Stipp, S L S

    2011-05-01

    On April 14, 2010, when meltwaters from the Eyjafjallajökull glacier mixed with hot magma, an explosive eruption sent unusually fine-grained ash into the jet stream. It quickly dispersed over Europe. Previous airplane encounters with ash resulted in sandblasted windows and particles melted inside jet engines, causing them to fail. Therefore, air traffic was grounded for several days. Concerns also arose about health risks from fallout, because ash can transport acids as well as toxic compounds, such as fluoride, aluminum, and arsenic. Studies on ash are usually made on material collected far from the source, where it could have mixed with other atmospheric particles, or after exposure to water as rain or fog, which would alter surface composition. For this study, a unique set of dry ash samples was collected immediately after the explosive event and compared with fresh ash from a later, more typical eruption. Using nanotechniques, custom-designed for studying natural materials, we explored the physical and chemical nature of the ash to determine if fears about health and safety were justified and we developed a protocol that will serve for assessing risks during a future event. On single particles, we identified the composition of nanometer scale salt coatings and measured the mass of adsorbed salts with picogram resolution. The particles of explosive ash that reached Europe in the jet stream were especially sharp and abrasive over their entire size range, from submillimeter to tens of nanometers. Edges remained sharp even after a couple of weeks of abrasion in stirred water suspensions. PMID:21518890

  16. Characterization and ecological risk assessment of nanoparticulate CeO2 as a diesel fuel catalyst.

    PubMed

    Batley, Graeme E; Halliburton, Brendan; Kirby, Jason K; Doolette, Casey L; Navarro, Divina; McLaughlin, Mike J; Veitch, Colin

    2013-08-01

    Nanoparticulate cerium dioxide (nano-CeO2 ), when combusted as an additive to diesel fuel, was transformed from 6 nm to 14 nm sizes into particles near 43 nm, with no obvious change in the unit cell dimensions or crystalline form. Cerium sulfate, if formed during combustion, was below detection limits. Ceria nanoparticles were agglomerated within the soot matrix, with a mean aerodynamic diameter near 100 nm. The dissolution of cerium from the dried ceria catalyst in synthetic soft water was extremely small (<0.0006% or <0.2 µg Ce/L), with particles being highly agglomerated (<450 nm). Agglomeration was reduced in the presence of humic acid. In the combusted samples, soot was dominant, and the solubility of cerium in soft water showed an almost 100-fold increase in the <1 nm fraction compared to that before combustion. It appeared that the nano-CeO2 remained agglomerated within the soot matrix and would not be present as dispersed nanoparticles in aquatic or soil environments. Despite the increased dissolution, the solubility was not sufficient for the combusted ceria to represent a risk in aquatic ecosystems. The predicted environmental concentrations were still orders of magnitude below the predicted no effects concentration of near 1 mg/L. In the soil environment, any cerium released from soot materials would interact with natural colloids, decreasing cerium concentrations in soil solutions and further minimizing the potential risk to soil organisms. PMID:23595783

  17. Workflow Integrating Fracture Permeability Characterization and Multiphase Flow Modeling for CO2 Storage and Risk Assessments in Fractured Reservoirs

    NASA Astrophysics Data System (ADS)

    Jin, G.; Pashin, J. C.

    2014-12-01

    Ensuring safe and permanent storage of sequestered CO2in naturally fractured geological media is vital for the success of geologic storage projects. Critical needs exist to develop advanced techniques to characterize and model fluid transport in naturally fractured reservoirs and seals. We have developed a scale-independent 3-D stochastic fracture permeability characterization workflow that employs multiple discrete fracture network (DFN) realizations. The workflow deploys a multidirectional flux-based upwind weighting scheme that is capable of modeling multiphase flow in highly heterogeneous fractured media. The techniques employed herein show great promise for increasing the accuracy of capacity determinations and the prediction of pressure footprints associated with injected CO2 plumes. The proposed workflow has been conducted in a simulation study of flow transport and risk assessment of CO2 injection into a deep fractured saline formation using geological parameters from Knox Group carbonate and Red Mountain shale rocks in central Alabama. A 3-D fracture permeability map was generated from multiple realizations of DFN models. A multiphase flow model composed of supercritical CO2 and saline water was applied to simulate CO2 plume evolution during and after injection. Injection simulation reveals significant permeability anisotropy that favors development of northeast-elongate CO2 plumes. The spreading front of the CO2 plume shows strong viscous fingering effects. Post-injection simulation indicates significant lateral spreading of CO2 near the top of the fractured formations because of the buoyancy of injectate in rock matrix and strata-bound vertical fractures. Risk assessment shows that although pressure drops faster in the fractured formations than in those lacking fractures, lateral movement of CO2 along natural fractures necessitates that the injectate be confined by widespread seals with high integrity.

  18. Prevalence, risk factors of infection and molecular characterization of trichomonads in puppies from French breeding kennels.

    PubMed

    Grellet, Aurélien; Brunopolack; Feugier, Alexandre; Boucraut-Baralon, Corine; Grandjean, Dominique; Vandewynckel, Laurine; Cian, Amandine; Meloni, Dionigia; Viscogliosi, Eric

    2013-11-01

    The trichomonad species Tritrichomonas fetus and Pentatrichomonas hominis were recently identified in the feces of dogs with diarrhea. However the prevalence and pathogenicity of these parasites in the canine population still remained poorly resolved. Therefore the aim of the present study was (1) to determine the prevalence of trichomonads infecting puppies living in French breeding kennels, (2) to confirm the predominance of P. hominis in dogs, (3) to investigate the genetic diversity of P. hominis isolates identified in the French canine population and (4) to evaluate the risk factors for infection by P. hominis and the influence of the parasite on feces consistency. A total of 215 both diarrheic and non-diarrheic puppies from 25 French breeding kennels were included in this epidemiological survey. Fecal samples from each puppy were examined for 6 gastrointestinal pathogens: parvovirus type 2 (CPV2), coronavirus, Toxocara canis, Cystoisospora ohioensis-complex, Cystoisospora canis, and Giardia intestinalis. A part of each collected stool was also tested for the presence of motile trichomonads by microscopy after culturing. The prevalence of trichomonad infection was 15.8% (34/215) among puppies and 20% (5/25) among breeding kennels. DNA from 26 of the 34 positive samples was successfully amplified using a trichomonad-specific primer pair. Analysis of the sequences of PCR products indicated that P. hominis was the only trichomonad infecting the canine population. All the puppies infected with P. hominis belonged to large breed dogs. Moreover, puppies from large breeding kennels, excreting a high level of G. intestinalis and/or excreting a high level of C. canis oocysts showed a higher probability of being positive for P. hominis infection. Univariate analysis also revealed an increased risk for P. hominis infection in puppies with abnormal feces. However, in a multivariate analysis, CPV2 was the only gastrointestinal pathogen associated with abnormal feces. Since

  19. Mercury study report to Congress. Volume 6. Characterization of human health and wildlife risks from anthropogenic mercury emissions in the United States. Sab review draft

    SciTech Connect

    Mahaffey, K.R.; Schoeny, R.; Rice, G.E.; Keating, M.H.

    1996-06-01

    The volume of the draft Mercury Study Report to Congress characterizes risk for mercury emitted to the environment from anthropogenic sources. The characterization volume describes human and wildlife health effects of mercury exposure with accompanying analysis of uncertainty in quantitative risk estimates. Exposure pathways for selected human and wildlife populations to mercury are considered, again accompanied by a discussion of uncertainty. The size of the fish-eating U.S. population and quantities of mercury consumed in fish are estimated, as are the number of maternal-fetal pairs for whom maternal fish consumption is projected to exceed levels identified to be of concern. Literature reports of mercury concentrations in tissues of fish-eating wildlife species are presented. The sizes of selected wildlife populations identified as potentially exposed to quantities of methylmercury associated with adverse health effects are estimated. An overall characterization of risk of mercury to human subpopulations and selected fish-consuming wildlife species is developed.

  20. The characterization and risk assessment of the `Red Forest` radioactive waste burial site at Chernobyl Nuclear Power Plant

    SciTech Connect

    Bungai, D.A.; Skalskij, A.S.; Dzhepo, S.P.; Waters, R.D.

    1996-06-01

    The `Red Forest` radioactive waste burials created during emergency clean-up activities at Chernobyl Nuclear Power Plant represent a serious source of radioactive contamination of the local ground water system with 9OSr concentration in ground water exceeding the drinking water standard by 3-4 orders of magnitude. In this paper we present results of our hydrogeological and radiological `Red Forest` site characterization studies, which allow us to estimate 9OSr subsurface migration parameters. We use then these parameters to assess long terrain radionuclide transport to groundwater and surface water, and to analyze associated health risks. Our analyses indicate that 9OSr transport via ground water pathway from `Red Forest` burials to the adjacent Pripyat River is relatively insignificant due to slow release of 9OSr from the waste burials (less than 1% of inventory per year) and due to long enough ground water residence time in the subsurface, which allows substantial decay of the radioactive contaminant. Tins result and our previous analyses indicate, that though conditions of radioactive waste storage in burials do not satisfy Ukrainian regulation on radiation protection, health risks caused by radionuclide migration to ground water from `Red Forest` burials do not justify application of expensive countermeasures.

  1. Clinical and molecular characterization of patients at risk for hereditary melanoma in southern Brazil.

    PubMed

    Ashton-Prolla, Patricia; Bakos, Lucio; Junqueira, Gerson; Giugliani, Roberto; Azevedo, Sergio J; Hogg, David

    2008-02-01

    Melanoma is the most dangerous of all common skin cancers, due to its propensity to metastasize. Therefore, identification of at-risk populations may allow early detection of disease at a curable stage. In Europe and North America, between 8-14% of melanoma patients have a family history of the disease, and a subset of these individuals possess germline mutations in the CDKN2A gene, which encodes the p16(INK4A) and p14(ARF) tumor suppressors. We identified 30 patients (29 families) from Southern Brazil, who had a family history of melanoma and/or pancreatic cancer; or a personal history of multiple primary melanoma. We screened this cohort for mutations in the CDKN2A and CDK4 genes, and detected two functional mutations: a G-34T transversion in 5'untranslated region; and a M53I alteration encoded in exon 2. Both mutants have been previously associated with melanoma and demonstrate founder effects. We conclude that germline mutations of CDKN2A occur in the Brazilian population, and that these mutations likely originated in Europe. PMID:17713569

  2. Redox subpopulations and the risk of cancer progression: a new method for characterizing redox heterogeneity

    NASA Astrophysics Data System (ADS)

    Xu, He N.; Li, Lin Z.

    2016-02-01

    It has been shown that a malignant tumor is akin to a complex organ comprising of various cell populations including tumor cells that are genetically, metabolically and functionally different. Our redox imaging data have demonstrated intra-tumor redox heterogeneity in all mouse xenografts derived from human melanomas, breast, prostate, and colon cancers. Based on the signals of NADH and oxidized flavoproteins (Fp, including flavin adenine dinucleotide (FAD)) and their ratio, i.e., the redox ratio, which is an indicator of mitochondrial metabolic status, we have discovered several distinct redox subpopulations in xenografts of breast tumors potentially recapitulating functional/metabolic heterogeneity within the tumor. Furthermore, xenografts of breast tumors with higher metastatic potential tend to have a redox subpopulation whose redox ratio is significantly different from that of tumors with lower metastatic potential and usually have a bi-modal distribution of the redox ratio. The redox subpopulations from human breast cancer samples can also be very complex with multiple subpopulations as determined by fitting the redox ratio histograms with multi- Gaussian functions. In this report, we present a new method for identifying the redox subpopulations within individual breast tumor xenografts and human breast tissues, which may be used to differentiate between breast cancer and normal tissue and among breast cancer with different risks of progression.

  3. Characterization and Potential Environmental Risks of Leachate from Shredded Rubber Mulches

    PubMed Central

    Kanematsu, Masakazu; Hayashi, Ai; Denison, Michael S.; Young, Thomas M.

    2009-01-01

    In order to determine whether shredded rubber mulches (RM) posed water quality risks when used in stormwater best management practices (BMPs) such as bioretention basins, batch leaching tests were conducted to identify and quantify constituents in leachates from RM such as metal ions, nutrients, total organic carbon (TOC), and aryl hydrocarbon receptor (AhR) activity (determined by the chemically activated luciferase gene expression (CALUX) bioassay) at varied temperature and initial pH values. The results indicate that aqueous extracts of RM contain high concentrations of zinc (Zn) compared with wood mulches (WM), and its concentration increased at lower pH and higher temperature. Although methanol extracts of RM displayed high AhR activity, none of the aqueous extracts of RM had significant activity. Hence, while unknown constituents that have significant AhR activity are present in RM, they appear to be not measurably extracted by water under environmental conditions relevant for stormwater (5 < pH < 9, 10 < T < 40°C). Our results suggests that organic constituents in water extracts of RM which have AhR activity may not be of significant concern while leaching of Zn from RM appears to be a potentially larger water quality issue for RM. PMID:19450864

  4. In Vivo Risk Analysis of Pancreatic Cancer Through Optical Characterization of Duodenal Mucosa

    PubMed Central

    Mutyal, Nikhil N.; Radosevich, Andrew J.; Bajaj, Shailesh; Konda, Vani; Siddiqui, Uzma D.; Waxman, Irving; Goldberg, Michael J.; Rogers, Jeremy D.; Gould, Bradley; Eshein, Adam; Upadhye, Sudeep; Koons, Ann; Gonzalez-Haba Ruiz, Mariano; Roy, Hemant K.; Backman, Vadim

    2015-01-01

    Objectives To reduce pancreatic cancer mortality, a paradigm shift in cancer screening is needed. Our group pioneered the use of low-coherence enhanced backscattering (LEBS) spectroscopy to predict the presence of pancreatic cancer by interrogating the duodenal mucosa. A previous ex vivo study (n = 203) demonstrated excellent diagnostic potential: sensitivity, 95%; specificity, 71%; and accuracy, 85%. The objective of the current case-control study was to evaluate this approach in vivo. Methods We developed a novel endoscope-compatible fiber-optic probe to measure LEBS in the periampullary duodenum of 41 patients undergoing upper endoscopy. This approach enables minimally invasive detection of the ultrastructural consequences of pancreatic field carcinogenesis. Results The LEBS parameters and optical properties were significantly altered in patients harboring adenocarcinomas (including early-stage) throughout the pancreas relative to healthy controls. Test performance characteristics were excellent with sensitivity = 78%, specificity = 85%, and accuracy = 81%. Moreover, the LEBS prediction rule was not confounded by patients’ demographics. Conclusion We demonstrate the feasibility of in vivo measurement of histologically normal duodenal mucosa to predict the presence of adenocarcinoma throughout the pancreas. This represents the next step in establishing duodenal LEBS analysis as a prescreening technique that identifies clinically asymptomatic patients who are at elevated risk of PC. PMID:25906443

  5. Towards improved characterization of high-risk releases using heterogeneous indoor sensor systems

    SciTech Connect

    Sreedharan, Priya; Sohn, Michael D.; Nazaroff, William W.; J. Gadgil, Ashok

    2010-06-30

    The sudden release of toxic contaminants that reach indoor spaces can be hazardous to building occupants. For an acutely toxic contaminant, the speed of the emergency response strongly influences the consequences to occupants. The design of a real time sensor system is made challenging both by the urgency and complex nature of the event, and by the imperfect sensors and models available to describe it. In this research, we use Bayesian modeling to combine information from multiple types of sensors to improve the characterization of a release. We discuss conceptual and algorithmic considerations for selecting and fusing information from disparate sensors. To explore system performance, we use both real tracer gas data from experiments in a three story building, along with synthetic data, including information from door position sensors. The added information from door position sensors is found to be useful for many scenarios, but not always. We discuss the physical conditions and design factors that affect these results, such as the influence of the door positions on contaminant transport. We highlight potential benefits of multisensor data fusion, challenges in realizing those benefits, and opportunities for further improvement.

  6. Molecular characterization of rabies virus isolates from Mexico: implications for transmission dynamics and human risk.

    PubMed

    De Mattos, C C; De Mattos, C A; Loza-Rubio, E; Aguilar-Setién, A; Orciari, L A; Smith, J S

    1999-10-01

    Twenty-eight samples from humans and domestic and wild animals collected in Mexico between 1990 and 1995 were characterized by using anti-nucleoprotein monoclonal antibodies and limited sequence analysis of the nucleoprotein gene. The variants of rabies viruses identified in these samples were compared with other isolates from Mexico and the rest of the Americas to establish epidemiologic links between cases and outbreaks and to increase the understanding of rabies epidemiology in the Western Hemisphere. Antigenic and genetic diversity was found in all samples from dogs and dog-related cases, suggesting a long-term endemic situation with multiple, independent cycles of virus transmission. Two isolates from bobcats were antigenically and genetically homologous to the rabies variant circulating in the Arizona gray fox population, indicating a wider distribution of this variant than previously reported. Rabies isolates from skunks were unrelated to any variant analyzed in this study and represent a previously unrecognized cycle of rabies transmission in skunks in Baja California Sur. Two antigenic and genetic variants co-circulating in southern and eastern Mexico were found in viruses obtained from cases epidemiologically related to vampire bats. These results serve as a baseline for the better understanding of the molecular epidemiology of rabies in Mexico. PMID:10548293

  7. Use of high spatial resolution satellite imagery to characterize landscapes at risk for bluetongue.

    PubMed

    Guis, Hélène; Tran, Annelise; de La Rocque, Stéphane; Baldet, Thierry; Gerbier, Guillaume; Barragué, Bruno; Biteau-Coroller, Fabienne; Roger, François; Viel, Jean-François; Mauny, Frédéric

    2007-01-01

    The recent and rapid spread in the Mediterranean Basin of bluetongue, a viral disease of ruminants transmitted by some species of Culicoides (biting midges), highlights the necessity of determining the conditions of its emergence. This study uses high spatial resolution satellite imagery and methods from landscape ecology science to identify environmental parameters related to bluetongue occurrence in Corsica, a French Mediterranean island where the disease occurred for the first time in 2000. A set of environmental variables recorded in the neighborhood of 80 sheep farms were related to case occurrence through a logistic regression model computed within three subsequent buffer distances of 0.5, 1 and 2 km. The results reveal the role of landscape metrics, particularly those characterizing land-use units such as prairies and woodlands, as well as farm type, latitude and sunshine to explain the presence of bluetongue. Internal and external validation both indicate that the best results are obtained with the 1 km buffer size model (area under Receiver Operating Characteristic curve = 0.9 for internal validation and 0.81 for external validation). The results show that high spatial resolution remote sensing (i.e. 10 m pixels) and landscape ecology approaches contribute to improving the understanding of bluetongue epidemiology. PMID:17583664

  8. Methods to identify and characterize developmental neurotoxicity for human health risk assessment. I: behavioral effects.

    PubMed Central

    Cory-Slechta, D A; Crofton, K M; Foran, J A; Ross, J F; Sheets, L P; Weiss, B; Mileson, B

    2001-01-01

    Alterations in nervous system function after exposure to a developmental neurotoxicant may be identified and characterized using neurobehavioral methods. A number of methods can evaluate alterations in sensory, motor, and cognitive functions in laboratory animals exposed to toxicants during nervous system development. Fundamental issues underlying proper use and interpretation of these methods include a) consideration of the scientific goal in experimental design, b) selection of an appropriate animal model, c) expertise of the investigator, d) adequate statistical analysis, and e) proper data interpretation. Strengths and weaknesses of the assessment methods include sensitivity, selectivity, practicality, and variability. Research could improve current behavioral methods by providing a better understanding of the relationship between alterations in motor function and changes in the underlying structure of these systems. Research is also needed to develop simple and sensitive assays for use in screening assessments of sensory and cognitive function. Assessment methods are being developed to examine other nervous system functions, including social behavior, autonomic processes, and biologic rhythms. Social behaviors are modified by many classes of developmental neurotoxicants and hormonally active compounds that may act either through neuroendocrine mechanisms or by directly influencing brain morphology or neurochemistry. Autonomic and thermoregulatory functions have been the province of physiologists and neurobiologists rather than toxicologists, but this may change as developmental neurotoxicology progresses and toxicologists apply techniques developed by other disciplines to examine changes in function after toxicant exposure. PMID:11250808

  9. Risk-Informed Safety Margin Characterization (RISMC): Integrated Treatment of Aleatory and Epistemic Uncertainty in Safety Analysis

    SciTech Connect

    R. W. Youngblood

    2010-10-01

    The concept of “margin” has a long history in nuclear licensing and in the codification of good engineering practices. However, some traditional applications of “margin” have been carried out for surrogate scenarios (such as design basis scenarios), without regard to the actual frequencies of those scenarios, and have been carried out with in a systematically conservative fashion. This means that the effectiveness of the application of the margin concept is determined in part by the original choice of surrogates, and is limited in any case by the degree of conservatism imposed on the evaluation. In the RISMC project, which is part of the Department of Energy’s “Light Water Reactor Sustainability Program” (LWRSP), we are developing a risk-informed characterization of safety margin. Beginning with the traditional discussion of “margin” in terms of a “load” (a physical challenge to system or component function) and a “capacity” (the capability of that system or component to accommodate the challenge), we are developing the capability to characterize probabilistic load and capacity spectra, reflecting both aleatory and epistemic uncertainty in system response. For example, the probabilistic load spectrum will reflect the frequency of challenges of a particular severity. Such a characterization is required if decision-making is to be informed optimally. However, in order to enable the quantification of probabilistic load spectra, existing analysis capability needs to be extended. Accordingly, the INL is working on a next-generation safety analysis capability whose design will allow for much more efficient parameter uncertainty analysis, and will enable a much better integration of reliability-related and phenomenology-related aspects of margin.

  10. Characterization of agricultural drought risk by a two-dimensional copula

    NASA Astrophysics Data System (ADS)

    Vergni, Lorenzo; Todisco, Francesca; Mannocchi, Francesco

    2015-04-01

    In this work, the joint probability distribution of two agricultural drought characteristics (Relative Severity, RS, and Onset, O) has been modeled by a two-dimensional copula. The application is illustrated with reference to a single-station case study (Perugia, Central Italy) and to the crop sunflower, widely grown in Central Italy, usually under rainfed conditions. The 86-year time series of daily precipitation and maximum and minimum temperature from the Perugia station (Central Italy) were used to simulate the soil water dynamics in the root-zone of sunflower. For each year, single seasonal values of RS and O have been quantified by applying the theory of runs to the soil water volume dynamics, with a threshold equal to the crop critical point. RS derives from the summation of the severities (i.e. total water stress) of the drought runs occurred during the growing season. The attribute 'relative' is here used because the severity value is corrected taking into account both the available water capacity of the soil and the growing season length. Thus, RS is a non-dimensional value ranging between 0 (no water stress) and 1 (maximum theoretical water stress for a given growing season length). The characteristic O describes the water stress temporal position (with respect to the growing season length) and it derives from a weighted average of the times of occurrence of the different drought runs (run severities being the weights). O is a non-dimensional value that expresses the temporal position of water stress as percentage of residual growing season, and it ranges between 0 (drought location at harvest) and 1 (drought location at seeding). The information provided by this characteristic can be considered particularly useful in agricultural drought risk management, because, as it is known, the drought impact on crop yield (being equal the severity) can vary substantially with the sensitivity of the growth stages affected by water stress conditions. The analysis

  11. Reduced Order Model Implementation in the Risk-Informed Safety Margin Characterization Toolkit

    SciTech Connect

    Mandelli, Diego; Smith, Curtis L.; Alfonsi, Andrea; Rabiti, Cristian; Cogliati, Joshua J.; Talbot, Paul W.; Rinaldi, Ivan; Maljovec, Dan; Wang, Bei; Pascucci, Valerio; Zhao, Haihua

    2015-09-01

    The RISMC project aims to develop new advanced simulation-based tools to perform Probabilistic Risk Analysis (PRA) for the existing fleet of U.S. nuclear power plants (NPPs). These tools numerically model not only the thermo-hydraulic behavior of the reactor primary and secondary systems but also external events temporal evolution and components/system ageing. Thus, this is not only a multi-physics problem but also a multi-scale problem (both spatial, µm-mm-m, and temporal, ms-s-minutes-years). As part of the RISMC PRA approach, a large amount of computationally expensive simulation runs are required. An important aspect is that even though computational power is regularly growing, the overall computational cost of a RISMC analysis may be not viable for certain cases. A solution that is being evaluated is the use of reduce order modeling techniques. During the FY2015, we investigated and applied reduced order modeling techniques to decrease the RICM analysis computational cost by decreasing the number of simulations runs to perform and employ surrogate models instead of the actual simulation codes. This report focuses on the use of reduced order modeling techniques that can be applied to any RISMC analysis to generate, analyze and visualize data. In particular, we focus on surrogate models that approximate the simulation results but in a much faster time (µs instead of hours/days). We apply reduced order and surrogate modeling techniques to several RISMC types of analyses using RAVEN and RELAP-7 and show the advantages that can be gained.

  12. A Risk-Based Strategy for Geomechanical Characterization of Potential CCS Sites to Prevent Earthquake Triggering

    NASA Astrophysics Data System (ADS)

    Zoback, M. D.

    2012-12-01

    For global CCS projects to significantly reduce greenhouse gas emissions, they must operate at levels on the order of one billion tonnes of carbon per year. In a recent paper*, M. D. Zoback and S. M. Gorelick argued that because of the enormous injection volumes (roughly equivalent to the 27 billions barrels of oil produced globally each year), the likelihood of triggering small-to-moderate size earthquakes made large-scale CCS "an extremely expensive and risky strategy for achieving significant reductions in greenhouse gas emissions". In this talk I will present examples from several sites in the relatively stable continental interior of the U.S. that demonstrate that the common assumption that injection of CO2 can proceed safely at pressures up to 1.5 times hydrostatic pressure (or about 70% of the overburden stress) is in excess of the value at which fault slip is triggered. It is important to note that Zoback and Gorelick emphasizes that CCS is an important and useful technology for reducing greenhouse gas emissions in specific situations. Injection into highly porous and permeable reservoirs that are laterally extensive would produce small increases in pressure in response to CO2 injection and weak, and poorly cemented sandstones would not be expected to deform through brittle faulting. In this context, I will outline several elements of a risk-based strategy for assessing the potential for earthquake triggering in potential CO2 repositories and present examples in which such a strategy has been successfully implemented. *Earthquake triggering and large-scale geologic storage of carbon dioxide, Mark D. Zoback and Steven M. Gorelick, Proc. National Acad. Sciences, (www.pnas.org/cgi/doi/10.1073/pnas.1202473109)

  13. Using NASA Remotely Sensed Data to Help Characterize Environmental Risk Factors for National Public Health Applications

    NASA Technical Reports Server (NTRS)

    Al-Hamdan, Mohammad; Crosson, William; Economou, Sigrid; Estes, Maurice, Jr.; Estes, Sue; Hemmings, Sarah; Kent, Shia; Quattrochi, Dale; Wade, Gina; McClure, Leslie

    2011-01-01

    NASA Marshall Space Flight Center is collaborating with the University of Alabama at Birmingham (UAB) School of Public Health and the Centers for Disease Control and Prevention (CDC) National Center for Public Health Informatics to address issues of environmental health and enhance public health decision making by utilizing NASA remotely sensed data and products. The objectives of this study are to develop high-quality spatial data sets of environmental variables, link these with public health data from a national cohort study, and deliver the linked data sets and associated analyses to local, state and federal end-user groups. Three daily environmental data sets will be developed for the conterminous U.S. on different spatial resolutions for the period 2003-2008: (1) spatial surfaces of estimated fine particulate matter (PM2.5) exposures on a 10-km grid utilizing the US Environmental Protection Agency (EPA) ground observations and NASA's MODerate-resolution Imaging Spectroradiometer (MODIS) data; (2) a 1-km grid of Land Surface Temperature (LST) using MODIS data; and (3) a 12-km grid of daily Solar Insolation (SI) using the North American Land Data Assimilation System (NLDAS) forcing data. These environmental data sets will be linked with public health data from the UAB REasons for Geographic And Racial Differences in Stroke (REGARDS) national cohort study to determine whether exposures to these environmental risk factors are related to cognitive decline and other health outcomes. These environmental datasets and public health linkage analyses will be disseminated to end-users for decision making through the CDC Wide-ranging Online Data for Epidemiologic Research (WONDER) system.

  14. Health Risk Assessment for Uranium in Groundwater - An Integrated Case Study Based on Hydrogeological Characterization and Dose Calculation

    NASA Astrophysics Data System (ADS)

    Franklin, M. R.; Veiga, L. H.; Py, D. A., Jr.; Fernandes, H. M.

    2010-12-01

    The uranium mining and milling facilities of Caetité (URA) is the only active uranium production center in Brazil. Operations take place at a very sensitive semi-arid region in the country where water resources are very scarce. Therefore, any contamination of the existing water bodies may trigger critical consequences to local communities because their sustainability is closely related to the availability of the groundwater resources. Due to the existence of several uranium anomalies in the region, groundwater can present radionuclide concentrations above the world average. The radiological risk associated to the ingestion of these waters have been questioned by members of the local communities, NGO’s and even regulatory bodies that suspected that the observed levels of radionuclide concentrations (specially Unat) could be related to the uranium mining and milling operations. Regardless the origin of these concentrations the fear that undesired health effects were taking place (e.g. increase in cancer incidence) remain despite the fact that no evidence - based on epidemiological studies - is available. This paper intends to present the connections between the local hydrogeology and the radiological characterization of groundwater in the neighboring areas of the uranium production center to understand the implications to the human health risk due to the ingestion of groundwater. The risk assessment was performed, taking into account the radiological and the toxicological risks. Samples from 12 wells have been collected and determinations of Unat, Thnat, 226Ra, 228Ra and 210Pb were performed. The radiation-related risks were estimated for adults and children by the calculation of the annual effective doses. The potential non-carcinogenic effects due to the ingestion of uranium were evaluated by the estimation of the hazard index (HI). Monte Carlo simulations were used to calculate the uncertainty associated with these estimates, i.e. the 95% confidence interval

  15. Characterization and assessment of potential environmental risk of tailings stored in seven impoundments in the Aries river basin, Western Romania

    PubMed Central

    2013-01-01

    Background The objective of this study was to examine the potential environmental risk of tailings resulted after precious and base metal ores processing, stored in seven impoundments located in the Aries river basin, Romania. The tailings were characterized by mineralogical and elemental composition, contamination indices, acid rock drainage generation potential and water leachability of hazardous/priority hazardous metals and ions. Multivariate statistical methods were used for data interpretation. Results Tailings were found to be highly contaminated with several hazardous/priority hazardous metals (As, Cu, Cd, Pb), and pose potential contamination risk for soil, sediments, surface and groundwater. Two out of the seven studied impoundments does not satisfy the criteria required for inert wastes, shows acid rock drainage potential and thus can contaminate the surface and groundwater. Three impoundments were found to be highly contaminated with As, Pb and Cd, two with As and other two with Cu. The tailings impoundments were grouped based on the enrichment factor, geoaccumulation index, contamination factor and contamination degree of 7 hazardous/priority hazardous metals (As, Cd, Cr, Cu, Ni, Pb, Zn) considered typical for the studied tailings. Principal component analysis showed that 47% of the elemental variability was attributable to alkaline silicate rocks, 31% to acidic S-containing minerals, 12% to carbonate minerals and 5% to biogenic elements. Leachability of metals and ions was ascribed in proportion of 61% to silicates, 11% to acidic minerals and 6% to the organic matter. A variability of 18% was attributed to leachability of biogenic elements (Na, K, Cl-, NO3-) with no potential environmental risk. Pattern recognition by agglomerative hierarchical clustering emphasized the grouping of impoundments in agreement with their contamination degree and acid rock drainage generation potential. Conclusions Tailings stored in the studied impoundments were found to

  16. Responses of Lyngbya wollei to algaecide exposures and a risk characterization associated with their use.

    PubMed

    Calomeni, Alyssa J; Iwinski, Kyla J; Kinley, Ciera M; McQueen, Andrew; Rodgers, John H

    2015-06-01

    To make informed decisions regarding management of noxious algal growths, water resource managers require information on responses of target and non-target species to algaecide exposures. Periodic treatments of Phycomycin®-SCP (sodium carbonate peroxyhydrate) followed by Algimycin®-PWF (gluconate and citrate chelated copper) to control Lyngbya wollei growths for ten years provided an opportunity for a risk evaluation of treated coves in Lay Lake, AL. Abiotic sediment characteristics (acid soluble copper concentrations, acid volatile sulfides, percent organic matter and cation exchange capacity) and survival of Hyalella azteca and Chironomus dilutus were measured in sediment samples from treated and untreated coves to assess the bioavailability of potential copper-residuals. In laboratory studies to seek a more effective approach for managing the growth of Lyngbya, six algaecide treatments consisting of combinations of copper-based algaecides (Cutrine®-Ultra, Clearigate® and Algimycin®- PWF), a hydrogen peroxide based algaecide (Phycomycin®-SCP) and an adjuvant (Cide-Kick II) were assessed for efficacy in controlling L. wollei sampled from Lay Lake. The most efficient algaecide treatment was determined based on post-treatment algal wet weight and visual observations of responses to exposures. To estimate the margin of safety for non-target organisms, Pimephales promelas was exposed to the most efficacious treatment and a treatment of Phycomycin®-SCP followed by Algimycin®-PWF. Results from sediment experiments demonstrated that there were no measureable copper residuals and no adverse effects on H. azteca and C. dilutus from sediments following ten years of copper-based algaecide treatments. Based on the laboratory results, a treatment of Phycomycin®-SCP at 10.1 mg H2O2/L followed by Cide-Kick II at 0.2 mg/L and Algimycin®- PWF at 0.26 mg Cu/L could control the growth of Lyngbya wollei from Lay Lake, AL and enhance the margin of safety for non

  17. Using NASA Remotely Sensed Data to Help Characterize Environmental Risk Factors for National Public Health Applications

    NASA Astrophysics Data System (ADS)

    Al-Hamdan, M. Z.; Crosson, W. L.; Economou, S.; Estes, M., Jr.; Estes, S. M.; Hemmings, S. N.; Kent, S.; Loop, M.; Puckett, M.; Quattrochi, D. A.; Wade, G.; McClure, L.

    2012-12-01

    The overall goal of this study is to address issues of environmental health and enhance public health decision making by using NASA remotely sensed data and products. This study is a collaboration between NASA Marshall Space Flight Center, Universities Space Research Association (USRA), the University of Alabama at Birmingham (UAB) School of Public Health and the Centers for Disease Control and Prevention (CDC) Office of Surveillance, Epidemiology and Laboratory Services. The objectives of this study are to develop high-quality spatial data sets of environmental variables, link these with public health data from a national cohort study, and deliver the environmental data sets and associated public health analyses to local, state and federal end-user groups. Three daily environmental data sets were developed for the conterminous U.S. on different spatial resolutions for the period 2003-2008: (1) spatial surfaces of estimated fine particulate matter (PM2.5) on a 10-km grid using US Environmental Protection Agency (EPA) ground observations and NASA's MODerate-resolution Imaging Spectroradiometer (MODIS) data; (2) a 1-km grid of MODIS Land Surface Temperature (LST); and (3) a 12-km grid of daily incoming solar radiation and maximum and minimum air temperature using the North American Land Data Assimilation System (NLDAS) data. These environmental datasets were linked with public health data from the UAB REasons for Geographic and Racial Differences in Stroke (REGARDS) national cohort study to determine whether exposures to these environmental risk factors are related to cognitive decline, stroke and other health outcomes. These environmental national datasets will also be made available to public health professionals, researchers and the general public via the CDC Wide-ranging Online Data for Epidemiologic Research (WONDER) system, where they can be aggregated to the county-level, state-level, or regional-level as per users' need and downloaded in tabular, graphical

  18. Using NASA Remotely Sensed Data to Help Characterize Environmental Risk Factors for National Public Health Applications

    NASA Technical Reports Server (NTRS)

    Al-Hamdan, Mohammad; Crosson, William; Economou, Sigrid; Estes,Maurice, Jr.; Estes, Sue; Hemmings, Sarah; Kent, Shia; Puckett, Mark; Quattrochi, Dale; Wade, Gina; McClure, Leslie

    2012-01-01

    The overall goal of this study is to address issues of environmental health and enhance public health decision making by using NASA remotely sensed data and products. This study is a collaboration between NASA Marshall Space Flight Center, Universities Space Research Association (USRA), the University of Alabama at Birmingham (UAB) School of Public Health and the Centers for Disease Control and Prevention (CDC) Office of Surveillance, Epidemiology and Laboratory Services. The objectives of this study are to develop high-quality spatial data sets of environmental variables, link these with public health data from a national cohort study, and deliver the environmental data sets and associated public health analyses to local, state and federal end ]user groups. Three daily environmental data sets were developed for the conterminous U.S. on different spatial resolutions for the period 2003-2008: (1) spatial surfaces of estimated fine particulate matter (PM2.5) on a 10-km grid using US Environmental Protection Agency (EPA) ground observations and NASA's MODerate-resolution Imaging Spectroradiometer (MODIS) data; (2) a 1-km grid of MODIS Land Surface Temperature (LST); and (3) a 12-km grid of daily incoming solar radiation and maximum and minimum air temperature using the North American Land Data Assimilation System (NLDAS) data. These environmental datasets were linked with public health data from the UAB REasons for Geographic and Racial Differences in Stroke (REGARDS) national cohort study to determine whether exposures to these environmental risk factors are related to cognitive decline, stroke and other health outcomes. These environmental national datasets will also be made available to public health professionals, researchers and the general public via the CDC Wide-ranging Online Data for Epidemiologic Research (WONDER) system, where they can be aggregated to the county-level, state-level, or regional-level as per users f need and downloaded in tabular, graphical

  19. Characterization of asymptomatic Plasmodium falciparum infection and its risk factors in pregnant women from the Republic of Congo.

    PubMed

    Francine, Ntoumi; Damien, Bakoua; Anna, Fesser; Michael, Kombo; Christevy, Vouvoungui J; Felix, Koukouikila-Koussounda

    2016-01-01

    Malaria in pregnancy remains a serious public health problem in the Republic of Congo despite the implementation of intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP) in 2006. The aim of this cross-sectional study was to characterize Plasmodium falciparum infections and determine possible risk factors in pregnant Congolese women attending an antenatal clinic in a periurban area of southern Brazzaville. This study was conducted from March 2012 to December 2013 in a site where several years ago, high malaria resistance to SP was reported. Pregnant women were enrolled during antenatal visits and the number of received IPTp-SP doses was recorded as well as individual sociodemographic data. Peripheral blood was collected and P. falciparum infection was checked by microscopy and by PCR targeting P. falciparum merozoite surface protein gene (msp2). Haemoglobin concentration was measured and P. falciparum positive samples were typed for msp2 allelic diversity. A total of 363 pregnant women were recruited. The prevalence of asymptomatic P. falciparum infection was 7% and 19% by microscopy and by PCR, respectively. More than one half (51.5%) of the pregnant women were anaemic. Multivariate analysis indicated that P. falciparum infection was associated with anaemia. It was also observed that women who have received IPTp-SP have significantly lower prevalence of infection. The administration of IPTp-SP did not influence the multiplicity of infection (MOI). This first study investigating asymptomatic malaria infection on pregnant women of the Republic of Congo shows that P. falciparum infections were clearly associated with maternal anaemia, and use of IPTp-SP reduced the risk of carrying asymptomatic infections. PMID:26477849

  20. Characterization of thigh and shank segment angular velocity during jump landing tasks commonly used to evaluate risk for ACL injury.

    PubMed

    Dowling, Ariel V; Favre, Julien; Andriacchi, Thomas P

    2012-09-01

    The dynamic movements associated with anterior cruciate ligament (ACL) injury during jump landing suggest that limb segment angular velocity can provide important information for understanding the conditions that lead to an injury. Angular velocity measures could provide a quick and simple method of assessing injury risk without the constraints of a laboratory. The objective of this study was to assess the inter-subject variations and the sensitivity of the thigh and shank segment angular velocity in order to determine if these measures could be used to characterize jump landing mechanisms. Additionally, this study tested the correlation between angular velocity and the knee abduction moment. Thirty-six healthy participants (18 male) performed drop jumps with bilateral and unilateral landing. Thigh and shank angular velocities were measured by a wearable inertial-based system, and external knee moments were measured using a marker-based system. Discrete parameters were extracted from the data and compared between systems. For both jumping tasks, the angular velocity curves were well defined movement patterns with high inter-subject similarity in the sagittal plane and moderate to good similarity in the coronal and transverse planes. The angular velocity parameters were also able to detect differences between the two jumping tasks that were consistent across subjects. Furthermore, the coronal angular velocities were significantly correlated with the knee abduction moment (R of 0.28-0.51), which is a strong indicator of ACL injury risk. This study suggested that the thigh and shank angular velocities, which describe the angular dynamics of the movement, should be considered in future studies about ACL injury mechanisms. PMID:22938373

  1. Caresoil: A multidisciplinar Project to characterize, remediate, monitor and evaluate the risk of contaminated soils in Madrid (Spain)

    NASA Astrophysics Data System (ADS)

    Muñoz-Martín, Alfonso; Antón, Loreto; Granja, Jose Luis; Villarroya, Fermín; Montero, Esperanza; Rodríguez, Vanesa

    2016-04-01

    Soil contamination can come from diffuse sources (air deposition, agriculture, etc.) or local sources, these last being related to anthropogenic activities that are potentially soil contaminating activities. According to data from the EU, in Spain, and particularly for the Autonomous Community of Madrid, it can be considered that heavy metals, toxic organic compounds (including Non Aqueous Phases Liquids, NAPLs) and combinations of both are the main problem of point sources of soil contamination in our community. The five aspects that will be applied in Caresoil Program (S2013/MAE-2739) in the analysis and remediation of a local soil contamination are: 1) the location of the source of contamination and characterization of soil and aquifer concerned, 2) evaluation of the dispersion of the plume, 3) application of effective remediation techniques, 4) monitoring the evolution of the contaminated soil and 5) risk analysis throughout this process. These aspects involve advanced technologies (hydrogeology, geophysics, geochemistry,...) that require new developing of knowledge, being necessary the contribution of several researching groups specialized in the fields previously cited, as they are those integrating CARESOIL Program. Actually two cases concerning hydrocarbon spills, as representative examples of soil local contamination in Madrid area, are being studied. The first is being remediated and we are monitoring this process to evaluate its effectiveness. In the second location we are defining the extent of contamination in soil and aquifer to define the most effective remediation technique.

  2. Characterization of the transport signals that mediate the nucleocytoplasmic traffic of low risk HPV11 E7

    SciTech Connect

    McKee, Courtney H.; Onder, Zeynep; Ashok, Aditya; Cardoso, Rebeca; Moroianu, Junona

    2013-08-15

    We previously discovered that nuclear import of low risk HPV11 E7 is mediated by its zinc-binding domain via a pathway that is independent of karyopherins/importins (Piccioli et al., 2010. Virology 407, 100–109). In this study we mapped and characterized a leucine-rich nuclear export signal (NES), {sub 76}IRQLQDLLL{sub 84}, within the zinc-binding domain that mediates the nuclear export of HPV11 E7 in a CRM1-dependent manner. We also identified a mostly hydrophobic patch {sub 65}VRLVV{sub 69} within the zinc-binding domain that mediates nuclear import of HPV11 E7 via hydrophobic interactions with the FG-repeats domain of Nup62. Substitutions of hydrophobic residues to alanine within the {sub 65}VRLVV{sub 69} sequence disrupt the nuclear localization of 11E7, whereas the R66A mutation has no effect. Overall the data support a model of nuclear entry of HPV11 E7 protein via hydrophobic interactions with FG nucleoporins at the nuclear pore complex. - Highlights: • HPV11 E7 has a leucine-rich nuclear export signal that mediates its nuclear export via CRM1. • HPV11 E7 interacts via its unique cNLS with the FG domain of Nup62. • Identification of a hydrophobic patch essential for nuclear localization of HPV11 E7.

  3. Estimating exposure and dose to characterize health risks: the role of human tissue monitoring in exposure assessment.

    PubMed Central

    Sexton, K; Callahan, M A; Bryan, E F

    1995-01-01

    Exposure assessment is an integral part of health risk characterization. Exposure assessments typically address three critical aspects of exposure: the number of people exposed to the environmental toxicant, at specific concentrations, for the time period of interest; the resulting dose; and the relative contribution of important sources and pathways to exposure/dose. Because historically both "point-of-contact" measurements and information about dose and related pharmacokinetic processes have been lacking, exposure assessments have had to rely on construction of "scenarios" to estimate exposure and dose. This could change, however, as advances in development of biologic markers of exposure and dose make it possible to measure and interpret toxicant concentrations in accessible human tissues. The increasing availability of "biomarkers," coupled with improvements in pharmacokinetic understanding, present opportunities to estimate ("reconstruct") exposure from measurements of dose and knowledge of intake and uptake parameters. Human tissue monitoring, however, is not a substitute for more traditional methods of measuring exposure, but rather a complementary approach. A combination of exposure measurements and dose measurements provides the most credible scientific basis for exposure assessment. PMID:7635107

  4. Assessing the joint impact of DNAPL source-zone behavior and degradation products on the probabilistic characterization of human health risk

    NASA Astrophysics Data System (ADS)

    Henri, Christopher V.; Fernàndez-Garcia, Daniel; de Barros, Felipe P. J.

    2016-02-01

    The release of industrial contaminants into the subsurface has led to a rapid degradation of groundwater resources. Contamination caused by Dense Non-Aqueous Phase Liquids (DNAPLs) is particularly severe owing to their limited solubility, slow dissolution and in many cases high toxicity. A greater insight into how the DNAPL source zone behavior and the contaminant release towards the aquifer impact human health risk is crucial for an appropriate risk management. Risk analysis is further complicated by the uncertainty in aquifer properties and contaminant conditions. This study focuses on the impact of the DNAPL release mode on the human health risk propagation along the aquifer under uncertain conditions. Contaminant concentrations released from the source zone are described using a screening approach with a set of parameters representing several scenarios of DNAPL architecture. The uncertainty in the hydraulic properties is systematically accounted for by high-resolution Monte Carlo simulations. We simulate the release and the transport of the chlorinated solvent perchloroethylene and its carcinogenic degradation products in randomly heterogeneous porous media. The human health risk posed by the chemical mixture of these contaminants is characterized by the low-order statistics and the probability density function of common risk metrics. We show that the zone of high risk (hot spot) is independent of the DNAPL mass release mode, and that the risk amplitude is mostly controlled by heterogeneities and by the source zone architecture. The risk is lower and less uncertain when the source zone is formed mostly by ganglia than by pools. We also illustrate how the source zone efficiency (intensity of the water flux crossing the source zone) affects the risk posed by an exposure to the chemical mixture. Results display that high source zone efficiencies are counter-intuitively beneficial, decreasing the risk because of a reduction in the time available for the production

  5. RISK CHARACTERIZATION OF DIOXINS

    EPA Science Inventory

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD; "Dioxin") is the most toxic member of a family of structurally related compounds which are ubiquitous environmental pollutants. The most potent of these, the polyhalogenated dibenzo-p-dioxins and furans, were never produced int...

  6. A Tiered Framework for Risk-Relevant Characterization and Ranking of Chemical Exposures: Applications to the National Children’s Study (NCS)

    PubMed Central

    Georgopoulos, Panos G.; Brinkerhoff, Christopher J.; Isukapalli, Sastry; Dellarco, Michael; Landrigan, Philip J.; Lioy, Paul J.

    2014-01-01

    A challenge for large-scale environmental health investigations such as the National Children’s Study (NCS), is characterizing exposures to multiple, co-occurring chemical agents with varying spatiotemporal concentrations and consequences modulated by biochemical, physiological, behavioral, socioeconomic, and environmental factors. Such investigations can benefit from systematic retrieval, analysis, and integration of diverse extant information on both contaminant patterns and exposure-relevant factors. This requires development, evaluation, and deployment of informatics methods that support flexible access and analysis of multiattribute data across multiple spatiotemporal scales. A new “Tiered Exposure Ranking” (TiER) framework, developed to support various aspects of risk-relevant exposure characterization, is described here, with examples demonstrating its application to the NCS. TiER utilizes advances in informatics computational methods, extant database content and availability, and integrative environmental/exposure/biological modeling to support both “discovery-driven” and “hypothesis-driven” analyses. “Tier 1” applications focus on “exposomic” pattern recognition for extracting information from multidimensional data sets, whereas second and higher tier applications utilize mechanistic models to develop risk-relevant exposure metrics for populations and individuals. In this article, “tier 1” applications of TiER explore identification of potentially causative associations among risk factors, for prioritizing further studies, by considering publicly available demographic/socioeconomic, behavioral, and environmental data in relation to two health endpoints (preterm birth and low birth weight). A “tier 2” application develops estimates of pollutant mixture inhalation exposure indices for NCS counties, formulated to support risk characterization for these endpoints. Applications of TiER demonstrate the feasibility of developing risk

  7. Overview of the Capstone depleted uranium study of aerosols from impact with armored vehicles: test setup and aerosol generation, characterization, and application in assessing dose and risk.

    PubMed

    Parkhurst, Mary Ann; Guilmette, Raymond A

    2009-03-01

    The Capstone Depleted Uranium (DU) Aerosol Characterization and Risk Assessment Study was conducted to generate data about DU aerosols generated during the perforation of armored combat vehicles with large-caliber DU penetrators, and to apply the data in assessments of human health risks to personnel exposed to these aerosols, primarily through inhalation, during the 1991 Gulf War or in future military operations. The Capstone study consisted of two components: 1) generating, sampling, and characterizing DU aerosols by firing at and perforating combat vehicles, and 2) applying the source-term quantities and characteristics of the aerosols to the evaluation of doses and risks. This paper reviews the background of the study including the bases for the study, previous reviews of DU particles and health assessments from DU used by the U.S. military, the objectives of the study components, the participants and oversight teams, and the types of exposures it was intended to evaluate. It then discusses exposure scenarios used in the dose and risk assessment and provides an overview of how the field tests and dose and risk assessments were conducted. PMID:19204481

  8. Risk-Informed Safety Margin Characterization Case Study: Selection of Electrical Equipment to Be Subjected to Environmental Qualification

    SciTech Connect

    D. P. Blanchard; R. W. Youngblood

    2014-06-01

    The Risk-Informed Safety Margin Characterization (RISMC) pathway of the DOE’s Light Water Reactor Sustainability (LWRS) program focuses on advancing the state of the art in safety analysis and risk assessment to support decision-making on nuclear power plant operation well beyond the originally designed lifetime of the plants (i.e., beyond 60 years). Among the issues being addressed in RISMC is the significance of SSC aging and how confident we are about our understanding of its impact on the margin between the loads SSCs are expected to see during normal operation and accident conditions, and the SSC capacities (their ability to resist those loads) as the SSCs age. In this paper, a summary is provided of a case study that examines SSC aging from an environmental qualification (EQ) perspective. The case study illustrates how the state of knowledge regarding SSC margin can be characterized given the overall integrated plant design, and was developed to demonstrate a method for deciding on which cables to focus, which cables are not so important from an environmental qualification margin standpoint, and what plant design features or operating characteristics determine the role that environmental qualification plays in establishing a safety case on which decisions regarding margin can be made. The selection of cables for which demonstration of margin with respect to aging and environmental challenges uses a technique known as Prevention Analysis. Prevention Analysis is a Boolean method for optimal selection of SSCs (that is, those combinations of SSCs both necessary and sufficient to meet a predetermined selection criterion) in a manner that allows demonstration that plant-level safety can be demonstrated by the collection of selected SSCs alone. Choosing the set of SSCs that is necessary and sufficient to satisfy the safety objectives, and demonstrating that the safety objectives can be met effectively, determines where resources are best allocated to assure SSC

  9. Mercury study report to Congress. Volume 7. Characterization of human health and wildlife risks from mercury exposure in the United States

    SciTech Connect

    Mahaffey, K.; Rice, G.E.; Schoeny, R.

    1997-12-01

    This volume characterizes risk for mercury emitted to the environment from anthropogenic sources. The characterization volume describes human and wildlife health effects of mercury exposure with accompanying analysis of uncertainty in quantitative risk estimates. Exposure pathways for selected human and wildlife populations to mercury are considered, again accompanied by a discussion of uncertainty. The size of the fish-eating U.S. populations and quantities of mercury consumed in fish are estimated, as are the number of maternal-fetal pairs for whom maternal fish consumption and the number of children are projected to exceed levels identified to be of concern. Literature reports of mercury concentrations in tissues of fish-eating wildlife species are presented. The sizes of selected wildlife populations identified as potentially exposed to quantities of methylmercury associated with adverse health effects are estimated. An overall characterization of risk of mercury to human subpopulations and selected fish-consuming wildlife species is developed. The volume of the Report presents sources of variability and uncertainty, as well as research needs.

  10. Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated groundwater at Beale Air Force Base in California

    SciTech Connect

    Bogen, K T; Daniels, J I; Hall, L C

    1999-09-01

    This study was designed to accomplish two objectives. The first was to provide to the US Air Force and the regulatory community quantitative procedures that they might want to consider using for addressing uncertainty and variability in exposure to better characterize potential health risk. Such methods could be used at sites where populations may now or in the future be faced with using groundwater contaminated with low concentrations of the chemical trichloroethylene (TCE). The second was to illustrate and explain the application of these procedures with respect to available data for TCE in ground water beneath an inactive landfill site that is undergoing remediation at Beale Air Force Base in California. The results from this illustration provide more detail than the more traditional conservative deterministic, screening-level calculations of risk, also computed for purposes of comparison. Application of the procedures described in this report can lead to more reasonable and equitable risk-acceptability criteria for potentially exposed populations at specific sites.

  11. CHARACTERIZE AGGREGATE AND CUMULATIVE RISK TO MANAGE RISK TO HUMANS EXPOSED TO MULTIPLE ENVIRONMENTAL STRESSORS: DOSE ADDITIVITY FOR PESTICIDE MIXTURES: BEHAVIORAL AND NEUROCHEMICAL EFFECTS

    EPA Science Inventory

    SUMMARY: The Agency’s default assumption for the cumulative assessment of the risk of mixtures is additivity based on either single-chemical potency (dose addition) or single-chemical effects (effect addition). NTD is developing models to accurately predict effects of complex mix...

  12. Integrating mechanistic and polymorphism data to characterize human genetic susceptibility for environmental chemical risk assessment in the 21st century

    EPA Science Inventory

    Response to environmental chemicals can vary widely among individuals and between population groups. In human health risk assessment, data on susceptibility can be utilized by deriving risk levels based on a study of a susceptible population and/or an uncertainty factor may be ap...

  13. Contribution for tier 1 of the ecological risk assessment of Cunha Baixa uranium mine (Central Portugal): I soil chemical characterization.

    PubMed

    Pereira, R; Antunes, S C; Marques, S M; Gonçalves, F

    2008-02-15

    Within the tier 1 of a site specific risk assessment, the pseudo-total concentrations (extracted with aqua regia) and the potential mobile fractions of metals were determined to perform a preliminary evaluation of risks posed by contaminated soils from an abandoned uranium mine (Mangualde, Central Portugal). Considering the mobile fractions of metals, extracted with artificial rain water, aluminium and uranium were the most concerning elements, since their concentrations were above soil quality criteria values (SQGVs) established for both elements. However, according to the evaluation based on potential mobile fractions of elements, rather than on pseudo-total metal concentrations the risks were limited to sites within the exploitation area, where contamination derives mainly from past in-situ leaching activities of pore ore as well as from the deposition of sludge from the effluent pond. The exclusion of other sites under evaluation, from the risk assessment process, requires additional data provided by soil screening ecotoxicological assays. PMID:17919686

  14. Characterization and source apportionment of health risks from ambient PM10 in Hong Kong over 2000-2011

    NASA Astrophysics Data System (ADS)

    Li, Zhiyuan; Yuan, Zibing; Li, Ying; Lau, Alexis K. H.; Louie, Peter K. K.

    2015-12-01

    Atmospheric particulate matter (PM) pollution is a major public health concern in Hong Kong. In this study, the spatiotemporal variations of health risks from ambient PM10 from seven air quality monitoring stations between 2000 and 2011 were analyzed. Positive matrix factorization (PMF) was adopted to identify major source categories of ambient PM10 and quantify their contributions. Afterwards, a point-estimated risk model was used to identify the inhalation cancer and non-cancer risks of PM10 sources. The long-term trends of the health risks from classified local and non-local sources were explored. Furthermore, the reason for the increase of health risks during high PM10 days was discussed. Results show that vehicle exhaust source was the dominant inhalation cancer risk (ICR) contributor (72%), whereas trace metals and vehicle exhaust sources contributed approximately 27% and 21% of PM10 inhalation non-cancer risk (INCR), respectively. The identified local sources accounted for approximately 80% of the ICR in Hong Kong, while contribution percentages of the non-local and local sources for INCR are comparable. The clear increase of ICR at high PM days was mainly attributed to the increase of contributions from coal combustion/biomass burning and secondary sulfate, while the increase of INCR at high PM days was attributed to the increase of contributions from the sources coal combustion/biomass burning, secondary nitrate, and trace metals. This study highlights the importance of health risk-based source apportionment in air quality management with protecting human health as the ultimate target.

  15. Acquisition of Multicomponent-4C Seismic Data from Unconventional Marine Reservoirs to Improve Exploration and Risk Attenuation in Reservoir Characterization

    NASA Astrophysics Data System (ADS)

    Aluka, I. J.

    2013-12-01

    The move to explore for commercial oil and gas from unconventional reservoirs such as shale/mudstone and tight gas sand reservoirs is having serious technical challenges. Multicomponent- 4C seismic data acquisition in marine settings will go a long way to assist oil and gas companies to discover unconventional resources with significant commercial value in the marine environments. Multicomponent technology has been proved to be effective in exploration and reservoir characterization and risk reduction. The technology provides enhanced strata images by reflecting independent subsurfaces, direct lithofacies and hydrocarbon indication compared to only conventional P-wave seismic stratigraphy. Multi component seismic data can be acquired in the marine settings by utilizing energy from towed air-gun arrays, and 4-component ocean bottom sensor (4-C OBS) packages deployed on the seafloor. Because the S waves do not travel through liquids, the sensors have to be deployed on the seafloor. The 4-component ocean bottom sensor comprises of a hydrophone, a gimbaled 3-component geophone as opposed to ungimbaled 3-component geophone. This gimbaled 3-component geophone is continually rotated by gravity to make sure that the moving-coil elements are placed in the crossline horizontal, and vertical, inline horizontal directions. Two or more vessels are used in marine multicompnent data acquisition. One vessel is a source vessel and the others are connected to the seafloor cable and record the 4-C seismic data. Every receiver on the seafloor is composed of a single 4-C sensor package, which is stationary during data recording. P-wave data are combination of particle-velocity wavefield recorded by the vertical geophone and pressure wavefield recorded by the hydrophone. The inline and crossline horizontal geophones record the particle-velocity data which are used to generate the upgoing reflected SV wavefield arriving at the seafloor. The downgoing P wavefield at non normal angles of

  16. RIPARIAN CHARACTERIZATION USING SUB-PIXEL ANALYSIS OF LANDSAT TM IMAGERY FOR USE IN ECOLOGICAL RISK ASSESSMENT

    EPA Science Inventory

    Landuse/land cover and riparian corridor characterization for 7 major watersheds in western Ohio was accomplished using sub-pixel analysis and traditional classification techniques. Areas
    representing forest, woodland, shrub, and herbaceous vegetation were delineated using a ...

  17. Potential for Adult-Based Epidemiological Studies to Characterize Overall Cancer Risks Associated with a Lifetime of CT Scans

    PubMed Central

    Shuryak, Igor; Lubin, Jay H.; Brenner, David J.

    2014-01-01

    Recent epidemiological studies have suggested that radiation exposure from pediatric CT scanning is associated with small excess cancer risks. However, the majority of CT scans are performed on adults, and most radiation-induced cancers appear during middle or old age, in the same age range as background cancers. Consequently, a logical next step is to investigate the effects of CT scanning in adulthood on lifetime cancer risks by conducting adult-based, appropriately designed epidemiological studies. Here we estimate the sample size required for such studies to detect CT-associated risks. This was achieved by incorporating different age-, sex-, time- and cancer type-dependent models of radiation carcinogenesis into an in silico simulation of a population-based cohort study. This approach simulated individual histories of chest and abdominal CT exposures, deaths and cancer diagnoses. The resultant sample sizes suggest that epidemiological studies of realistically sized cohorts can detect excess lifetime cancer risks from adult CT exposures. For example, retrospective analysis of CT exposure and cancer incidence data from a population-based cohort of 0.4 to 1.3 million (depending on the carcinogenic model) CT-exposed UK adults, aged 25–65 in 1980 and followed until 2015, provides 80% power for detecting cancer risks from chest and abdominal CT scans. PMID:24828111

  18. Variations of emission characterization of PAHs emitted from different utility boilers of coal-fired power plants and risk assessment related to atmospheric PAHs.

    PubMed

    Wang, Ruwei; Liu, Guijian; Zhang, Jiamei

    2015-12-15

    Coal-fired power plants (CFPPs) represent important source of atmospheric PAHs, however, their emission characterization are still largely unknown. In this work, the concentration, distribution and gas-particle partitioning of PM10- and gas-phase PAHs in flue gas emitted from different coal-fired utility boilers were investigated. Moreover, concentration and distribution in airborne PAHs from different functional areas of power plants were studied. People's inhalatory and dermal exposures to airborne PAHs at these sites were estimated and their resultant lung cancer and skin cancer risks were assessed. Results indicated that the boiler capacity and operation conditions have significant effect on PAH concentrations in both PM10 and gas phases due to the variation of combustion efficiency, whereas they take neglected effect on PAH distributions. The wet flue gas desulphurization (WFGD) takes significant effect on the scavenging of PAH in both PM10 and gas phases, higher scavenging efficiency were found for less volatile PAHs. PAH partitioning is dominated by absorption into organic matter and accompanied by adsorption onto PM10 surface. In addition, different partitioning mechanism is observed for individual PAHs, which is assumed arising from their chemical affinity and vapor pressure. Risk assessment indicates that both inhalation and dermal contact greatly contribute to the cancer risk for CFPP workers and nearby residents. People working in workshop are exposed to greater inhalation and dermal exposure risk than people living in nearby vicinity and working office. PMID:26298851

  19. Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated ground water at Beale Air Force Base in California

    SciTech Connect

    Daniels, J I; Bogen, K T; Hall, L C

    1999-10-05

    Conservative deterministic, screening-level calculations of exposure and risk commonly are used in quantitative assessments of potential human-health consequences from contaminants in environmental media. However, these calculations generally are based on multiple upper-bound point estimates of input parameters, particularly for exposure attributes, and can therefore produce results for decision makers that actually overstate the need for costly remediation. Alternatively, a more informative and quantitative characterization of health risk can be obtained by quantifying uncertainty and variability in exposure. This process is illustrated in this report for a hypothetical population at a specific site at Beale Air Force Base in California, where there is trichloroethylene (TCE) contaminated ground water and a potential for future residential use. When uncertainty and variability in exposure were addressed jointly for this case, the 95th-percentile upper-bound value of individual excess lifetime cancer risk was a factor approaching 10 lower than the most conservative deterministic estimate. Additionally, the probability of more than zero additional cases of cancer can be estimated, and in this case it is less than 0.5 for a hypothetical future residential population of up to 26,900 individuals present for any 7.6-y interval of a 70-y time period. Clearly, the results from application of this probabilistic approach can provide reasonable and equitable risk-acceptability criteria for a contaminated site.

  20. Characterization of risk/exposure to climate extremes for the Brazilian Northeast—case study: Rio Grande do Norte

    NASA Astrophysics Data System (ADS)

    Silva, Bruce Kelly N.; Lucio, Paulo Sergio

    2015-10-01

    Climate change would increase the risk of floods or droughts. So far, only a few studies have projected changes in extremes on a regional or local scale. None of these studies relied on multiple climate proxies. Only some studies have started to estimate the exposure to flooding or drought as a proxy of risk; so, here, we present an exercise in risk analysis. Studies of climate change and its impacts rarely yield consensus on the distribution of exposure, vulnerability or possible outcomes. In addition, Northeast Brazil (NEB) is known for its temporal and spatial variability of rainfall and several studies have investigated this variability in order to understand damaging episodes such as droughts and floods. In NEB, the phenomenon of drought is a complex issue because millions of people are affected, and so, it is an important object of study in various fields of knowledge. One way of trying to argue about this phenomenon is through the concept of vulnerability. In this preliminary study, one will determine the risk or exposure factor to drought, which is one component of vulnerability, mainly concerning agricultural activities. The drought risk/exposure indicator was constructed based on three indices: the standardized precipitation index (SPI), the precipitation concentration period (PCP) and the precipitation concentration degree (PCD). The exposure indices showed an increase in high values from 1979 to 2008. On the contrary, the period from 1967 to 1996 showed that the risk factor in some micro-regions had low indices in a larger number; one can note that the dynamics of the factor is in an evolution between high and extremes.

  1. Yucca Mountain transportation routes: Preliminary characterization and risk analysis; Volume 2, Figures [and] Volume 3, Technical Appendices

    SciTech Connect

    Souleyrette, R.R. II; Sathisan, S.K.; di Bartolo, R.

    1991-05-31

    This report presents appendices related to the preliminary assessment and risk analysis for high-level radioactive waste transportation routes to the proposed Yucca Mountain Project repository. Information includes data on population density, traffic volume, ecologically sensitive areas, and accident history.

  2. Prospect theory and body mass: characterizing psychological parameters for weight-related risk attitudes and weight-gain aversion

    PubMed Central

    Lim, Seung-Lark; Bruce, Amanda S.

    2015-01-01

    We developed a novel decision-making paradigm that allows us to apply prospect theory in behavioral economics to body mass. 67 healthy young adults completed self-report measures and two decision-making tasks for weight-loss, as well as for monetary rewards. We estimated risk-related preference and loss aversion parameters for each individual, separately for weight-loss and monetary rewards choice data. Risk-seeking tendency for weight-loss was positively correlated with body mass index in individuals who desired to lose body weight, whereas the risk-seeking for momentary rewards was not. Risk-seeking for weight-loss was correlated to excessive body shape preoccupations, while aversion to weight-gain was correlated with self-reports of behavioral involvement for successful weight-loss. We demonstrated that prospect theory can be useful in explaining the decision-making process related to body mass. Applying prospect theory is expected to advance our understanding of decision-making mechanisms in obesity, which might prove helpful for improving healthy choices. PMID:25852628

  3. Characterization of the ecological interactions of Roundup Ready 2 Yield® soybean, MON 89788, for use in ecological risk assessment.

    PubMed

    Horak, Michael J; Rosenbaum, Eric W; Phillips, Samuel L; Kendrick, Daniel L; Carson, David; Clark, Pete L; Nickson, Thomas E

    2015-01-01

    As part of an ecological risk assessment, Roundup Ready 2 Yield® soybean (MON 89788) was compared to a conventional control soybean variety, A3244, for disease and arthropod damage, plant response to abiotic stress and cold, effects on succeeding plant growth (allelopathic effects), plant response to a bacterial symbiont, and effects on the ability of seed to survive and volunteer in a subsequent growing season. Statistically significant differences between MON 89788 and A3244 were considered in the context of the genetic variation known to occur in soybean and were assessed for their potential impact on plant pest (weed) potential and adverse environmental impact. The results of these studies revealed no effects of the genetic modification that would result in increased pest potential or adverse environmental impact of MON 89788 compared with A3244. This paper illustrates how such characterization studies conducted in a range of environments where the crop is grown are used in an ecological risk assessment of the genetically modified (GM) crop. Furthermore, risk assessors and decision makers use this information when deciding whether to approve a GM crop for cultivation in-or grain import into-their country. PMID:26177011

  4. Analytical characterization of movements of the spinal column and risk assessment due to repeated movements of the upper limbs of building painters.

    PubMed

    Antonucci, Andrea; Forcella, Laura; Bonfiglioli, Roberta; Boscolo, Paolo; Violante, Francesco Saverio

    2016-09-01

    Manual activities of construction workers may induce musculoskeletal disorders. This study on a group of painters aimed to analytically characterize movements of the spinal column by both lumbar motion monitor and television cameras and to determine, using the Occupational Repetitive Actions (OCRA) Index method, the risk exerted by repeated movements of the upper limbs. The main results are: painting with a roller generally exposes workers to a lesser risk for upper limbs than painting with a brush; a roller-stick fixed at the wrong length can lead to stretching of the back at lumbar and cervical levels; to remain within the range of 'acceptable risk' (OCRA Index evaluation), a worker should not paint a vertical wall for over 3 h if using a roller and 2.5 h if painting with a brush; and, on average, a painter who paints for 5 h in a day lifts the bucket about 120,140 times. PMID:27092402

  5. Characterization of Apps and Other e-Tools for Medication Use: Insights Into Possible Benefits and Risks

    PubMed Central

    van der Laar, Catharina Walthera Egbertha; de Jong, Charlie; Weda, Marjolein; Hegger, Ingrid

    2016-01-01

    Background In the past years, an enormous increase in the number of available health-related applications (apps) has occurred, from approximately 5800 in 2011 to over 23,000 in 2013, in the iTunes store. However, little is still known regarding the use, possible effectiveness, and risks of these applications. In this study, we focused on apps and other e-tools related to medicine use. A large subset of the general population uses medicines and might benefit from tools that aid in the use of medicine. Objective The aim of the present study was to gain more insight into the characteristics, possible risks, and possible benefits of health apps and e-tools related to medication use. Methods We first made an inventory of apps and other e-tools for medication use (n=116). Tools were coded by two independent researchers, based on the information available in the app stores and websites. Subsequently, for one type of often downloaded apps (aimed at people with diabetes), we investigated users’ experiences using an online questionnaire. Results Results of the inventory show that many apps for medication use are available and that they mainly offer simple functionalities. In line with this, the most experienced benefit by users of apps for regulating blood glucose levels in the online questionnaire was “information quick and conveniently available”. Other often experienced benefits were improving health and self-reliance. Results of the inventory show that a minority of the apps for medication use has potentially high risks and for many of the apps it is unclear whether and how personal data are stored. In contrast, online questionnaire among users of apps for blood glucose regulation indicates that they hardly ever experience problems or doubts considering reliability and/or privacy. Although, respondents do mention to experience disadvantages of use due to incomplete apps and apps with poor ease of use. Respondents not using app(s) indicate that they might use them

  6. Epidemiological Characterization and Risk Factors of Allergic Rhinitis in the General Population in Guangzhou City in China

    PubMed Central

    Lin, Zhi Bin; Peng, Hua; Lu, Han Gui; Yang, Yan; Yin, Jia; Li, Tian Ying

    2014-01-01

    The prevalence of allergic rhinitis (AR) in China has increased with an apparent geographic variation. The current study aims to investigate the AR prevalence/classification, diagnosis/treatment conditions, trigger factors, and risk factors in the general population of Guangzhou, the third biggest city in China. A cross-sectional survey was performed in the citizens in Guangzhou from December 2009 to March 2010 by using a stratified multistage cluster sampling method. All subjects were asked to complete a comprehensive questionnaire via a face to face interview. A total of 9,899 questionnaires were valid. The prevalence rate of AR in the general population of Guangzhou was 6.24%, with a significant higher prevalence in urban area (8.32%) versus rural area (3.43%). Among the AR subjects, most (87%) were diagnosed with intermittent AR and 87% suffered from moderate-severe symptoms. High percentages of the AR patients did not have previously physician-based diagnosis (34%) or specific medical treatment (55%). Morning time, winter season, and cold air were the most common trigger factors of AR. Family history of AR, current living place, living place during babyhood, smoking, home renovation, and pet ownership were the significant risk factors associated with AR prevalence in the population. The study demonstrated comprehensive epidemiological and clinical information about the AR in Guangzhou population. Change of living environment and lifestyles had strong impacts on the prevalence of AR. Public health policies should help the patients benefit from a proper diagnosis/treatment and specifically target the local risk factors, in order to control the AR incidence. PMID:25514026

  7. Cross exploitation of geo-databases and earth observation data for stakes characterization in the framework of multi-risk analysis and management: RASOR examples

    NASA Astrophysics Data System (ADS)

    Tholey, Nadine; Yesou, Herve; Maxant, Jerome; Montabord, Myldred; Studer, Mathias; Faivre, Robin; Rudari, Roberto; de Fraipont, Paul

    2016-04-01

    In the context of risk analysis and management, information is needed on the landscape under investigation, especially for vulnerability assessment purposes where landuse and stakes characterization is of prime importance for the knowledge and description of exposure elements in modelling scenarios. Such thematic information over at-risk areas can be extracted from available global, regional or local scale open sources databases (e.g. ESA-Globcover, Natural Earth, Copernicus core services, OSM, …) or derived from the exploitation of EO satellite images at high and very high spatial resolution (e.g. SPOT, soon Sentinel2, Pleiades, WorldView, …) over territories where this type of information is not available or not sufficiently up to date. However, EO data processing, and derived results highlight also the gap between what would be needed for a complete representation of vulnerability , i.e. a functional description of the land use, a structural description of the buildings including their functional use , and what is reasonable accessible by exploiting EO data, i.e. a biophysical description of the land cover at different spatial resolution from decametric scales to sub-metric ones, especially for urban block and building information. Potential and limits of these multi-scale and multi-sources of geo-information will be illustrated by examples related to different types of landscape and urban settlements in Asia (Indonesia), Europe (Greece), and the Caribbean (Haiti) regions, and exploited within the framework of the RASOR (Rapid Analysis and Spatialisation Of Risk) project (European Commission FP7) which is developing a platform to perform multi-hazard risk analysis to support the full cycle of disaster management.

  8. Modeling approaches for characterizing and evaluating environmental exposure to engineered nanomaterials in support of risk-based decision making.

    PubMed

    Hendren, Christine Ogilvie; Lowry, Michael; Grieger, Khara D; Money, Eric S; Johnston, John M; Wiesner, Mark R; Beaulieu, Stephen M

    2013-02-01

    As the use of engineered nanomaterials becomes more prevalent, the likelihood of unintended exposure to these materials also increases. Given the current scarcity of experimental data regarding fate, transport, and bioavailability, determining potential environmental exposure to these materials requires an in depth analysis of modeling techniques that can be used in both the near- and long-term. Here, we provide a critical review of traditional and emerging exposure modeling approaches to highlight the challenges that scientists and decision-makers face when developing environmental exposure and risk assessments for nanomaterials. We find that accounting for nanospecific properties, overcoming data gaps, realizing model limitations, and handling uncertainty are key to developing informative and reliable environmental exposure and risk assessments for engineered nanomaterials. We find methods suited to recognizing and addressing significant uncertainty to be most appropriate for near-term environmental exposure modeling, given the current state of information and the current insufficiency of established deterministic models to address environmental exposure to engineered nanomaterials. PMID:23293982

  9. Methods to identify and characterize developmental neurotoxicity for human health risk assessment. III: pharmacokinetic and pharmacodynamic considerations.

    PubMed Central

    Dorman, D C; Allen, S L; Byczkowski, J Z; Claudio, L; Fisher, J E; Fisher, J W; Harry, G J; Li, A A; Makris, S L; Padilla, S; Sultatos, L G; Mileson, B E

    2001-01-01

    We review pharmacokinetic and pharmacodynamic factors that should be considered in the design and interpretation of developmental neurotoxicity studies. Toxicologic effects on the developing nervous system depend on the delivered dose, exposure duration, and developmental stage at which exposure occurred. Several pharmacokinetic processes (absorption, distribution, metabolism, and excretion) govern chemical disposition within the dam and the nervous system of the offspring. In addition, unique physical features such as the presence or absence of a placental barrier and the gradual development of the blood--brain barrier influence chemical disposition and thus modulate developmental neurotoxicity. Neonatal exposure may depend on maternal pharmacokinetic processes and transfer of the xenobiotic through the milk, although direct exposure may occur through other routes (e.g., inhalation). Measurement of the xenobiotic in milk and evaluation of biomarkers of exposure or effect following exposure can confirm or characterize neonatal exposure. Physiologically based pharmacokinetic and pharmacodynamic models that incorporate these and other determinants can estimate tissue dose and biologic response following in utero or neonatal exposure. These models can characterize dose--response relationships and improve extrapolation of results from animal studies to humans. In addition, pharmacologic data allow an experimenter to determine whether exposure to the test chemical is adequate, whether exposure occurs during critical periods of nervous system development, whether route and duration of exposure are appropriate, and whether developmental neurotoxicity can be differentiated from direct actions of the xenobiotic. PMID:11250810

  10. Polycyclic aromatic hydrocarbons (PAHs) in sediments of Zhelin Bay, the largest mariculture base on the eastern Guangdong coast, South China: Characterization and risk implications.

    PubMed

    Gu, Yang-Guang; Ke, Chang-Liang; Liu, Qi; Lin, Qin

    2016-09-15

    We investigated distribution, sources, and potential risks of polycyclic aromatic hydrocarbons (PAHs) in the surface sediments from the largest mariculture base in the eastern part of the province of Guangdong in southern China. Total concentrations of ∑PAHs were 29.38-815.46ng/g (dry weight), with a mean of 421.48ng/g. The composition of PAHs was characterized by an abundance of low molecular weight PAHs (2-3 benzenoid ring), and Phenanthrene (PHE), Anthracene (AN) and Fluoranthene (FA) were the predominant constituents. PAHs in this area appear to have mainly originated from petroleum sources and the combustion of grass, wood, and coal. PAHs in surface sediments of Zhelin Bay had a 9% incidence of causing adverse biological effects on aquatic organisms, according to the mean effects range-median quotient. PMID:27287864

  11. A risk-based focused decision-management approach for justifying characterization of Hanford tank waste. June 1996, Revision 1; April 1997, Revision 2

    SciTech Connect

    Colson, S.D.; Gephart, R.E.; Hunter, V.L.; Janata, J.; Morgan, L.G.

    1997-12-31

    This report describes a disciplined, risk-based decision-making approach for determining characterization needs and resolving safety issues during the storage and remediation of radioactive waste stored in Hanford tanks. The strategy recommended uses interactive problem evaluation and decision analysis methods commonly used in industry to solve problems under conditions of uncertainty (i.e., lack of perfect knowledge). It acknowledges that problem resolution comes through both the application of high-quality science and human decisions based upon preferences and sometimes hard-to-compare choices. It recognizes that to firmly resolve a safety problem, the controlling waste characteristics and chemical phenomena must be measurable or estimated to an acceptable level of confidence tailored to the decision being made.

  12. Multi-decadal Variability of Flood Risk in Southwestern Canadian Prairie Rivers as Characterized by the PDO and ENSO

    NASA Astrophysics Data System (ADS)

    Gurrapu, S.; St Jacques, J. M.; Sauchyn, D.; Hodder, K. R.

    2014-12-01

    The 2013 floods across southern Alberta, Canada, are considered to be one of the worst natural disasters in recent Canadian history. This region is highly vulnerable to flooding during spring as the frozen ground restricts infiltration and the melting snow directly contributes to streamflow. Studies have concluded that the 2013 floods in Alberta were a result of heavier snowpack from winter precipitation and higher amounts of spring precipitation as rain over the eastern slopes of the Rockies. Although this flood is considered to be less than the 100-year flood of the region, the effects were economically devastating. The return periods of floods are generally determined under the assumption that the annual peak flow series are independent and identically distributed (i.i.d.). However, researchers have demonstrated that this assumption is not valid in Australia and that the i.i.d. assumption can lead to under- or over-estimation of the true long-term flood risk. The Pacific Decadal Oscillation (PDO) and the El Niño-Southern Oscillation (ENSO) have a strong impact on western Canadian hydroclimate via teleconnections. The negative phase of the PDO and La Niña typically produce heavier snowpack across the prairies compared to that during the positive phase of PDO and El Niño. In this study, we explore the connections between the PDO, ENSO and the peak annual streamflow in southwestern Canadian prairie rivers. Daily averaged annual peak flow records from 22 rivers were stratified according to the PDO phases and ENSO states and fit to the Log-Pearson III (LP3) distribution. We determined that the flood risk is significantly higher in the negative phase of the PDO and is enhanced during La Niña episodes within the negative PDO phase. To ensure these results were not due to sampling error or unequal record lengths, a regional index approach was also employed, which confirmed these results. Our results are important for the optimal planning and design of flood control

  13. Opioid detection in maternal and neonatal hair and meconium: characterization of an at-risk population and implications to fetal toxicology.

    PubMed

    Moller, Monique; Karaskov, Tatyana; Koren, Gideon

    2010-06-01

    Identification of maternal opioid abuse in pregnancy is often difficult to ascertain in the absence of a reliable self-report. We aimed to characterize an at-risk neonatal population for opioid exposures as well as other drugs of abuse and alcohol. From June 2007 to January 2009, 563 neonatal hair and 1318 meconium specimens were assessed for opioids and were positive in 11.4% and 17.0%, respectively. Neonates testing positive for opioids in hair or meconium analysis were also more likely to test positive for other licit and illicit substances (odds ratiohair, 1.75; 95% confidence interval, 1.03-2.97; odds ratiomeconium, 1.61; 95% confidence interval, 1.16-2.22). Specifically, a positive neonatal hair test for opioids also predicted a positive result for oxycodone. In addition, a positive meconium test result for opioids was associated with positive results for cocaine, oxycodone, methadone, benzodiazepines, and fatty acid ethyl esters (alcohol). Finally, there was a significant correlation between maternal and neonatal hair test results for opioids (Spearman rank rho = 0.657, P = 0.03). Understanding the addiction profiles of these women may lead to better clinical and social management and may largely benefit an at-risk population. PMID:20418801

  14. Competing Uses of Underground Systems Related to Energy Supply: Applying Single- and Multiphase Simulations for Site Characterization and Risk-Analysis

    NASA Astrophysics Data System (ADS)

    Kissinger, A.; Walter, L.; Darcis, M.; Flemisch, B.; Class, H.

    2012-04-01

    Global climate change, shortage of resources and the resulting turn towards renewable sources of energy lead to a growing demand for the utilization of subsurface systems. Among these competing uses are Carbon Capture and Storage (CCS), geothermal energy, nuclear waste disposal, "renewable" methane or hydrogen storage as well as the ongoing production of fossil resources like oil, gas, and coal. Besides competing among themselves, these technologies may also create conflicts with essential public interests like water supply. For example, the injection of CO2 into the underground causes an increase in pressure reaching far beyond the actual radius of influence of the CO2 plume, potentially leading to large amounts of displaced salt water. Finding suitable sites is a demanding task for several reasons. Natural systems as opposed to technical systems are always characterized by heterogeneity. Therefore, parameter uncertainty impedes reliable predictions towards capacity and safety of a site. State of the art numerical simulations combined with stochastic approaches need to be used to obtain a more reliable assessment of the involved risks and the radii of influence of the different processes. These simulations may include the modeling of single- and multiphase non-isothermal flow, geo-chemical and geo-mechanical processes in order to describe all relevant physical processes adequately. Stochastic approaches have the aim to estimate a bandwidth of the key output parameters based on uncertain input parameters. Risks for these different underground uses can then be made comparable with each other. Along with the importance and the urgency of the competing processes this may lead to a more profound basis for a decision. Communicating risks to stake holders and a concerned public is crucial for the success of finding a suitable site for CCS (or other subsurface utilization). We present and discuss first steps towards an approach for addressing the issue of competitive

  15. A Study of Basal Cell Carcinoma in South Asians for Risk Factor and Clinicopathological Characterization: A Hospital Based Study

    PubMed Central

    Mahajan, Bharat Bhushan; Kaur, Sandeep; Yadav, Ashish; Singh, Navtej; Singh, Amarbir

    2014-01-01

    Objectives. Although the incidence of skin cancers in India (part of South Asia) is low, the absolute number of cases may be significant due to large population. The existing literature on BCC in India is scant. So, this study was done focusing on its epidemiology, risk factors, and clinicopathological aspects. Methods. A hospital based cross-sectional study was conducted in Punjab, North India, from 2011 to 2013. History, examination and histopathological confirmation were done in all the patients visiting skin department with suspected lesions. Results. Out of 36 confirmed cases, 63.9% were females with mean ± SD age being 60.9 ± 14.2 years. Mean duration of disease was 4.7 years. Though there was statistically significant higher sun exposure in males compared to females (P value being 0.000), BCC was commoner in females, explainable by intermittent sun exposure (during household work in the open kitchens) in women. Majority of patients (88.9%) had a single lesion. Head and neck region was involved in 97.2% of cases, with nose being the commonest site (50%) with nodular/noduloulcerative morphology in 77.8% of cases. Pigmentation was evident in 22.2% of cases clinically. Nodular variety was the commonest histopathological variant (77.8%). Conclusions. This study highlights a paradoxically increasing trend of BCC with female preponderance, preferential involvement of nose, and higher percentage of pigmentation in Indians. PMID:25530883

  16. Atherosclerotic plaque tissue characterization in 2D ultrasound longitudinal carotid scans for automated classification: a paradigm for stroke risk assessment.

    PubMed

    Acharya, U Rajendra; Mookiah, Muthu Rama Krishnan; Vinitha Sree, S; Afonso, David; Sanches, Joao; Shafique, Shoaib; Nicolaides, Andrew; Pedro, L M; Fernandes E Fernandes, J; Suri, Jasjit S

    2013-05-01

    In the case of carotid atherosclerosis, to avoid unnecessary surgeries in asymptomatic patients, it is necessary to develop a technique to effectively differentiate symptomatic and asymptomatic plaques. In this paper, we have presented a data mining framework that characterizes the textural differences in these two classes using several grayscale features based on a novel combination of trace transform and fuzzy texture. The features extracted from the delineated plaque regions in B-mode ultrasound images were used to train several classifiers in order to prepare them for classification of new test plaques. Our CAD system was evaluated using two different databases consisting of 146 (44 symptomatic to 102 asymptomatic) and 346 (196 symptomatic and 150 asymptomatic) images. Both these databases differ in the way the ground truth was determined. We obtained classification accuracies of 93.1 and 85.3 %, respectively. The techniques are low cost, easily implementable, objective, and non-invasive. For more objective analysis, we have also developed novel integrated indices using a combination of significant features. PMID:23292291

  17. Characterization of individuals at high risk of developing melanoma in Latin America: bases for genetic counseling in melanoma

    PubMed Central

    Puig, Susana; Potrony, Miriam; Cuellar, Francisco; Puig-Butille, Joan Anton; Carrera, Cristina; Aguilera, Paula; Nagore, Eduardo; Garcia-Casado, Zaida; Requena, Celia; Kumar, Rajiv; Landman, Gilles; Costa Soares de Sá, Bianca; Gargantini Rezze, Gisele; Facure, Luciana; de Avila, Alexandre Leon Ribeiro; Achatz, Maria Isabel; Carraro, Dirce Maria; Duprat Neto, João Pedreira; Grazziotin, Thais C.; Bonamigo, Renan R.; Rey, Maria Carolina W.; Balestrini, Claudia; Morales, Enrique; Molgo, Montserrat; Bakos, Renato Marchiori; Ashton-Prolla, Patricia; Giugliani, Roberto; Larre Borges, Alejandra; Barquet, Virginia; Pérez, Javiera; Martínez, Miguel; Cabo, Horacio; Cohen Sabban, Emilia; Latorre, Clara; Carlos-Ortega, Blanca; Salas-Alanis, Julio C; Gonzalez, Roger; Olazaran, Zulema; Malvehy, Josep; Badenas, Celia

    2016-01-01

    Purpose: CDKN2A is the main high-risk melanoma-susceptibility gene, but it has been poorly assessed in Latin America. We sought to analyze CDKN2A and MC1R in patients from Latin America with familial and sporadic multiple primary melanoma (SMP) and compare the data with those for patients from Spain to establish bases for melanoma genetic counseling in Latin America. Genet Med 18 7, 727–736. Methods: CDKN2A and MC1R were sequenced in 186 Latin American patients from Argentina, Brazil, Chile, Mexico, and Uruguay, and in 904 Spanish patients. Clinical and phenotypic data were obtained. Genet Med 18 7, 727–736. Results: Overall, 24 and 14% of melanoma-prone families in Latin America and Spain, respectively, had mutations in CDKN2A. Latin American families had CDKN2A mutations more frequently (P = 0.014) than Spanish ones. Of patients with SMP, 10% of those from Latin America and 8.5% of those from Spain had mutations in CDKN2A (P = 0.623). The most recurrent CDKN2A mutations were c.-34G>T and p.G101W. Latin American patients had fairer hair (P = 0.016) and skin (P < 0.001) and a higher prevalence of MC1R variants (P = 0.003) compared with Spanish patients. Genet Med 18 7, 727–736. Conclusion: The inclusion criteria for genetic counseling of melanoma in Latin America may be the same criteria used in Spain, as suggested in areas with low to medium incidence, SMP with at least two melanomas, or families with at least two cases among first- or second-degree relatives. Genet Med 18 7, 727–736. PMID:26681309

  18. Successful Characterization Strategies for the Active High Risk Y-12 National Security Complex 9201-5 (Alpha-5) Facility, Oak Ridge, TN - 12164

    SciTech Connect

    Birchfield, Joseph W. III; Albrecht, Linda

    2012-07-01

    Building 9201-5 (Alpha 5) was completed in May 1944 and served as a production facility for National Nuclear Security Administration (NNSA) Y-12 Weapons Plant. During the Manhattan Project, it functioned as a uranium enrichment facility. The facility was renovated and altered over the years, converting the calutrons to support other missions. Alpha 5 consists of 4 floors and a basement measuring approximately 600,000 square feet. The facility contains various pieces of equipment remaining from legacy operations. A significant amount (approximately 200,000 kgs) of mercury (Hg) has been spilled in the facility over the operational history of the building. To further complicate matters, beryllium (Be) contamination in 9201-5 is found throughout approximately sixty percent of the facility. Concentrations varying from very low (< 0.2 micrograms (μg)/100 cm{sup 2}) to areas where concentrations are relatively high, approximately 600 μg/100 cm{sup 2}, in regulated beryllium areas. The primary site related contaminants (SRCs) for the waste in this facility are enriched uranium, depleted uranium, beryllium and mercury. This facility represents the highest environmental risk for DOE-ORO EM and NNSA at Y-12 and must be quickly addressed to minimize impacts to future Y-12 missions, as well as human health and the environment. As part of the American Recovery and Reinvestment Act (ARRA), approximately 700,000 cubic feet of legacy material was removed in 2010 and 2011. In addition, characterization of the 9201-5 facility was scheduled in the winter and spring of 2011. This activity was initiated in January 2011 and was completed in July 2011. Heavy schedule pressure was further complicated by the fact that this building has active utility, security and process systems. Given these complex variables, a unique, out of the box characterization strategy was forged in an effort to bound radiological and chemical contaminants, as well as providing the appropriate level of quality to

  19. Methods for Addressing Uncertainty and Variability to Characterize Potential Health Risk from Trichloroethylene-Contaminated Ground Water at Beale Air Force Base in California:Integration of Uncertainty and Variability in Pharmacokinetics and Dose-Response

    SciTech Connect

    Bogen, K T

    2001-05-24

    Traditional estimates of health risk are typically inflated, particularly if cancer is the dominant endpoint and there is fundamental uncertainty as to mechanism(s) of action. Risk is more realistically characterized if it accounts for joint uncertainty and interindividual variability within a systematic probabilistic framework to integrate the joint effects on risk of distributed parameters of all (linear as well as nonlinear) risk-extrapolation models involved. Such a framework was used to characterize risks to potential future residents posed by trichloroethylene (TCE) in ground water at an inactive landfill site on Beale Air Force Base in California. Variability and uncertainty were addressed in exposure-route-specific estimates of applied dose, in pharmacokinetically based estimates of route-specific metabolized fractions of absorbed TCE, and in corresponding biologically effective doses estimated under a genotoxic/linear (MA{sub G}) vs. a cytotoxic/nonlinear (MA{sub c}) mechanistic assumption for TCE-induced cancer. Increased risk conditional on effective dose was estimated under MA{sub G} based on seven rodent-bioassay data sets, and under MA{sub c} based on mouse hepatotoxicity data. Mean and upper-bound estimates of combined risk calculated by the unified approach were <10{sup -6} and 10{sup -4}, respectively, while corresponding estimates based on traditional deterministic methods were >10{sup -5} and 10{sup -4}, respectively. It was estimated that no TCE-related harm is likely to occur due to any plausible residential exposure scenario involving the site. The systematic probabilistic framework illustrated is particularly suited to characterizing risks that involve uncertain and/or diverse mechanisms of action.

  20. Characterization and Risk Factor Analysis of Osteoporosis in a Large Cohort of Patients with Chronic Graft-versus-Host Disease.

    PubMed

    Pirsl, Filip; Curtis, Lauren M; Steinberg, Seth M; Tella, Sri Harsha; Katić, Mašenjka; Dobbin, Marnie; Hsu, Jennifer; Hakim, Fran T; Mays, Jacqueline W; Im, Annie P; Pulanić, Dražen; Mitchell, Sandra A; Baruffaldi, Judy; Masuch, Licia; Halverson, David C; Gress, Ronald E; Barsony, Julianna; Pavletic, Steven Z

    2016-08-01

    The National Institutes of Health Chronic Graft-versus-Host Disease (cGVHD) Consensus Project Ancillary and Supportive Care Guidelines recommend annual assessment of bone mineral density (BMD) to monitor bone health. The study of osteoporosis in patients with cGVHD has been limited to small numbers of patients, and the guidelines are based on experience with other chronic diseases and expert opinion. We hypothesized that the prevalence of osteoporosis is high in a cohort of 258 patients with moderate to severe cGVHD because of prolonged exposure to risk factors for osteoporosis after allogeneic hematopoietic stem cell transplantation. We defined osteoporosis using BMD criteria (T-score ≤-2.5) at 3 anatomic sites-the femoral neck (FN), lumbar spine (LS), and total hip (TH)-and characterized risk factors through univariate and multivariate analyses. We found that low body weight (FN, P < .0001; LS, P = .0002; TH, P < .0001), malnutrition (FN, P = .0002; LS, P = .03; TH, P = .0076), higher platelet count (FN, P = .0065; TH, P = .0025), higher average National Institutes of Health organ score (FN, P = .038), higher prednisone dose (LS, P = .032), lower complement component 3 (LS, P = .0073), and physical inactivity (FN, P = .01) were associated with osteoporosis in at least 1 site. T-scores were significantly lower in the FN compared with the LS or TH (P < .0001 for both). The prevalence of osteoporosis and osteopenia was high (17% and 60%, respectively), supporting current recommendations for frequent monitoring of BMD. The association of higher platelet count in patients with cGVHD and osteoporosis has not been reported previously and represents a new area of interest in the study of osteoporosis after allogeneic hematopoietic stem cell transplantation. PMID:27118572

  1. Characterizing Tumor Heterogeneity With Functional Imaging and Quantifying High-Risk Tumor Volume for Early Prediction of Treatment Outcome: Cervical Cancer as a Model

    SciTech Connect

    Mayr, Nina A.; Huang Zhibin; Wang, Jian Z.; Lo, Simon S.; Fan, Joline M.; Grecula, John C.; Sammet, Steffen; Sammet, Christina L.; Jia Guang; Zhang Jun; Knopp, Michael V.; Yuh, William T.C.

    2012-07-01

    Purpose: Treatment response in cancer has been monitored by measuring anatomic tumor volume (ATV) at various times without considering the inherent functional tumor heterogeneity known to critically influence ultimate treatment outcome: primary tumor control and survival. This study applied dynamic contrast-enhanced (DCE) functional MRI to characterize tumors' heterogeneous subregions with low DCE values, at risk for treatment failure, and to quantify the functional risk volume (FRV) for personalized early prediction of treatment outcome. Methods and Materials: DCE-MRI was performed in 102 stage IB{sub 2}-IVA cervical cancer patients to assess tumor perfusion heterogeneity before and during radiation/chemotherapy. FRV represents the total volume of tumor voxels with critically low DCE signal intensity (<2.1 compared with precontrast image, determined by previous receiver operator characteristic analysis). FRVs were correlated with treatment outcome (follow-up: 0.2-9.4, mean 6.8 years) and compared with ATVs (Mann-Whitney, Kaplan-Meier, and multivariate analyses). Results: Before and during therapy at 2-2.5 and 4-5 weeks of RT, FRVs >20, >13, and >5 cm{sup 3}, respectively, significantly predicted unfavorable 6-year primary tumor control (p = 0.003, 7.3 Multiplication-Sign 10{sup -8}, 2.0 Multiplication-Sign 10{sup -8}) and disease-specific survival (p = 1.9 Multiplication-Sign 10{sup -4}, 2.1 Multiplication-Sign 10{sup -6}, 2.5 Multiplication-Sign 10{sup -7}, respectively). The FRVs were superior to the ATVs as early predictors of outcome, and the differentiating power of FRVs increased during treatment. Discussion: Our preliminary results suggest that functional tumor heterogeneity can be characterized by DCE-MRI to quantify FRV for predicting ultimate long-term treatment outcome. FRV is a novel functional imaging heterogeneity parameter, superior to ATV, and can be clinically translated for personalized early outcome prediction before or as early as 2-5 weeks

  2. Characterization of a Family with Rare Deletions in CNTNAP5 and DOCK4 Suggests Novel Risk Loci for Autism and Dyslexia

    PubMed Central

    Pagnamenta, Alistair T.; Bacchelli, Elena; de Jonge, Maretha V.; Mirza, Ghazala; Scerri, Thomas S.; Minopoli, Fiorella; Chiocchetti, Andreas; Ludwig, Kerstin U.; Hoffmann, Per; Paracchini, Silvia; Lowy, Ernesto; Harold, Denise H.; Chapman, Jade A.; Klauck, Sabine M.; Poustka, Fritz; Houben, Renske H.; Staal, Wouter G.; Ophoff, Roel A.; O'Donovan, Michael C.; Williams, Julie; Nöthen, Markus M.; Schulte-Körne, Gerd; Deloukas, Panos; Ragoussis, Jiannis; Bailey, Anthony J.; Maestrini, Elena; Monaco, Anthony P.

    2010-01-01

    Background Autism spectrum disorders (ASDs) are characterized by social, communication, and behavioral deficits and complex genetic etiology. A recent study of 517 ASD families implicated DOCK4 by single nucleotide polymorphism (SNP) association and a microdeletion in an affected sibling pair. Methods The DOCK4 microdeletion on 7q31.1 was further characterized in this family using QuantiSNP analysis of 1M SNP array data and reverse transcription polymerase chain reaction. Extended family members were tested by polymerase chain reaction amplification of junction fragments. DOCK4 dosage was measured in additional samples using SNP arrays. Since QuantiSNP analysis identified a novel CNTNAP5 microdeletion in the same affected sibling pair, this gene was sequenced in 143 additional ASD families. Further polymerase chain reaction-restriction fragment length polymorphism analysis included 380 ASD cases and suitable control subjects. Results The maternally inherited microdeletion encompassed chr7:110,663,978-111,257,682 and led to a DOCK4-IMMP2L fusion transcript. It was also detected in five extended family members with no ASD. However, six of nine individuals with this microdeletion had poor reading ability, which prompted us to screen 606 other dyslexia cases. This led to the identification of a second DOCK4 microdeletion co-segregating with dyslexia. Assessment of genomic background in the original ASD family detected a paternal 2q14.3 microdeletion disrupting CNTNAP5 that was also transmitted to both affected siblings. Analysis of other ASD cohorts revealed four additional rare missense changes in CNTNAP5. No exonic deletions of DOCK4 or CNTNAP5 were seen in 2091 control subjects. Conclusions This study highlights two new risk factors for ASD and dyslexia and demonstrates the importance of performing a high-resolution assessment of genomic background, even after detection of a rare and likely damaging microdeletion using a targeted approach. PMID:20346443

  3. CagA status & genetic characterization of metronidazole resistant strains of H. pylori from: A region at high risk of gastric cancer

    PubMed Central

    Yue, Jin-Yong; Yue, Jing; Wang, Ming-Yi; Song, Wen-chong; Gao, Xiao-Zhong

    2014-01-01

    Objective: The aim of study was to determine relationship between cagA and genetic characterization of metronidazole (MTZ) resistant H. pylori strains from a region at high risk of gastric cancer. Methods: 172 H. pylori strains were isolated from the patients with dyspeptic symptoms, and antimicrobial susceptibility testing for MTZ was assessed by E-test. rdxA and frxA genes were amplified using PCR among the MTZ resistant isolates. The status of the plasmid and classes 1~3 integrons were investigated in all isolates. Results: MTZ was detected in 88 isolates (51.16%). Variations in the rdxA gene leading to alterations of amino acids in RdxA proteins were identified in all MTZ resistant strains. FrxA contained missense alterations in 55 MTZ resistant isolates, while the premature truncation of FrxA was caused by frameshift mutations in 9 MTZ resistant strains. Plasmid was found in one MTZ sensitive strain (0.58%), and none of Class 1~3 integrases gene was detected in the studied isolates. The conservative cagA fragment was obtained from all clinical isolates of H. pylori. The sequence of cagA 3' variable region in 164 strains were obtained, including East Asian-type (122, 74.39%) and Western-type (42, 25.61%). Prevalence of Western-type cagA 3' variable region was significantly higher in MTZ resistant (33.73%, 28/83) than those of MTZ-sensitive strains (17.28%, 14/81) (p=0.02). Conclusion: A high prevalence of MTZ resistance was found in the region, and bacterial chromosome mutations in the rdxA and frxA gene still contribute to the high-level MTZ resistance. H. pylori strains characterized with West-type cagA 3’ variable region tend to acquire MTZ resistance in the region. PMID:25097521

  4. Characterizing the HIV risks and potential pathways to HIV infection among transgender women in Côte d'Ivoire, Togo and Burkina Faso

    PubMed Central

    Stahlman, Shauna; Liestman, Benjamin; Ketende, Sosthenes; Kouanda, Seni; Ky-Zerbo, Odette; Lougue, Marcel; Diouf, Daouda; Anato, Simplice; Tchalla, Jules; Bamba, Amara; Drame, Fatou Maria; Ezouatchi, Rebecca; Kouamé, Abo; Baral, Stefan D

    2016-01-01

    Introduction Transgender women are at high risk for the acquisition and transmission of HIV. However, there are limited empiric data characterizing HIV-related risks among transgender women in sub-Saharan Africa. The objective of these analyses is to determine what factors, including sexual behaviour stigma, condom use and engagement in sex work, contribute to risk for HIV infection among transgender women across three West African nations. Methods Data were collected via respondent-driven sampling from men who have sex with men (MSM) and transgender women during three- to five-month intervals from December 2012 to October 2015 across a total of six study sites in Togo, Burkina Faso and Côte d'Ivoire. During the study visit, participants completed a questionnaire and were tested for HIV. Chi-square tests were used to compare the prevalence of variables of interest between transgender women and MSM. A multilevel generalized structural equation model (GSEM) was used to account for clustering of observations within study sites in the multivariable analysis, as well as to estimate mediated associations between sexual behaviour stigma and HIV infection among transgender women. Results In total, 2456 participants meeting eligibility criteria were recruited, of which 453 individuals identified as being female/transgender. Transgender women were more likely than MSM to report selling sex to a male partner within the past 12 months (p<0.01), to be living with HIV (p<0.01) and to report greater levels of sexual behaviour stigma as compared with MSM (p<0.05). In the GSEM, sexual behaviour stigma from broader social groups was positively associated with condomless anal sex (adjusted odds ratio (AOR)=1.33, 95% confidence interval (CI)=1.09, 1.62) and with selling sex (AOR=1.23, 95% CI=1.02, 1.50). Stigma from family/friends was also associated with selling sex (AOR=1.42, 95% CI=1.13, 1.79), although no significant associations were identified with prevalent HIV infection

  5. Geomorphological Characterization of Atenquique Basin in the Eastern Sector of the Volcan-Nevado-Colima, Jalisco, Mexico, As an Input to the Risk Assessment of Debris Flows.

    NASA Astrophysics Data System (ADS)

    Flores-Pena, S.; Suarez-Plascencia, C.

    2014-12-01

    The Atenquique river basin drains the eastern sector of the Volcanic Complex (VC) Volcan-Nevado de Colima, located on the border of the states of Jalisco and Colima. To use the digital geomorphological analysis 1:50000 scale mapping provided by INEGI and Landsat images, manipulating it in ArcGIS 10.2 developing the DEM that was the basis for morphometric characterization. The results show that the basin is divided into five sub-basins, with the main Atenquique (SAT) and Arroyo Seco (SAS), calculating the compactness coefficient (Kc) and the coefficient of sinuosity indicate that SAT is the most prone to floods due to straight and slightly sinuous channels. However, the density of dissection shows a more developed drainage network on the SAT, with slopes up to 84° and 600 m deep. The drainage basin has its source at an altitude of 4260 m and its mouth is in the Tuxpan River at 1040 m, which has a relative height of 2800 m; has a funnel-shaped elongated west-east, its outstanding average in the sector are Mountain 44° and 10° the piedmont. The SAT has a total area of 81.8 km2, with a dendritic river network, where the first order streams reach an 82.99%, and second order streams are the 13.4% of the total, these values show that most of the slopes of the basin have incipient development valleys and steep slopes. The basin has had 3 debris flows in recent 58 years; these are formed by large volumes of rock and mud that covered the town of Atenquique and paper mill located at the mouth of the Tuxpan River, caused deaths and significant economic damage. Its genesis is associated with the end of the summer rainy season, so he also worked in the hydrological analysis in order to determine the volume of runoff in the basin. The results of this work are used as input for the determining the risk levels in the study area, and may also be used by the municipality of Tuxpan, in order to define policies to manage risk and reduce future risks to the industrial town of

  6. [Risk and risk perception].

    PubMed

    de Vries, N K

    2002-06-01

    After having delineated the concept of risk and having described the type of risks that are relevant to dental practice, an overview of empirical and theoretical work on risk perception is given. The perception of risks is determined both by the actual magnitude and by perceptual bias, originating from either general perceptual phenomena such as (cognitive) availability or the ego-relevance of risks: persons in general underestimate risks for themselves as compared to the risks for others (unrealistic optimism). PMID:12092334

  7. Characterization of a former dump site in the Lagoon of Venice contaminated by municipal solid waste incinerator bottom ash, and estimation of possible environmental risk.

    PubMed

    Rigo, Chiarafrancesca; Zamengo, Luca; Rampazzo, Giancarlo; Argese, Emanuele

    2009-10-01

    Bottom ash from a municipal solid waste incinerator on a former contaminated site, the island of Sacca San Biagio (Lagoon of Venice), was examined in order to evaluate levels of pollutants and their potential mobility and availability. Heavy metal concentrations were determined and the actual contamination of the site was compared with national legislation on polluted sites. The site was mainly contaminated by zinc, copper and lead. Physico-chemical characterization of bottom ash was carried out by SEM (Scanning Electron Microscopy) with micro-analysis by EDS (Energy Dispersive X-ray Spectroscopy) and XRD (X-ray Diffractometry), for information on newly formed minerals. SEM-EDS analysis revealed the presence of particles, compounds and clusters containing heavy metals and, in particular, the presence of barium sulfate, which was assumed to be a site-specific compound. Similarities between bottom ash and atmospheric PM10 collected on the adjacent island of Sacca Fisola were studied and a risk of aerodispersion of the fine fraction of ash was assumed. Lastly, in order to evaluate the potentially available fraction of metals (non-residual fraction) and the directly exchangeable fraction, two single extraction procedures with HCl and citric acid were carried out, respectively. Results showed a relatively low concentration of readily phyto-available metals, as well as the high concentrations found for some heavy metals (Cu, Pb, Zn) in the potentially mobilizable fraction. PMID:19695669

  8. Methods for Addressing Uncertainty and Variability to Characterize Potential Health Risk From Trichloroethylene-Contaminated Ground Water Beale Air Force Base in California: Integration of Uncertainty and Variability in Pharmacokinetics and Dose-Response

    SciTech Connect

    Bogen, K.T.

    1999-09-29

    Traditional estimates of health risk are typically inflated, particularly if cancer is the dominant endpoint and there is fundamental uncertainty as to mechanism(s) of action. Risk is more realistically characterized if it accounts for joint uncertainty and interindividual variability after applying a unified probabilistic approach to the distributed parameters of all (linear as well as nonlinear) risk-extrapolation models involved. Such an approach was applied to characterize risks to potential future residents posed by trichloroethylene (TCE) in ground water at an inactive landfill site on Beale Air Force Base in California. Variability and uncertainty were addressed in exposure-route-specific estimates of applied dose, in pharmacokinetically based estimates of route-specific metabolized fractions of absorbed TCE, and in corresponding biologically effective doses estimated under a genotoxic/linear (MA{sub g}) vs. a cytotoxic/nonlinear (MA{sub c}) mechanistic assumption for TCE-induced cancer. Increased risk conditional on effective dose was estimated under MA{sub G} based on seven rodent-bioassay data sets, and under MA, based on mouse hepatotoxicity data. Mean and upper-bound estimates of combined risk calculated by the unified approach were <10{sup -6} and <10{sup -4}, respectively, while corresponding estimates based on traditional deterministic methods were >10{sup -5} and >10{sup -4}, respectively. It was estimated that no TCE-related harm is likely occur due any plausible residential exposure scenario involving the site. The unified approach illustrated is particularly suited to characterizing risks that involve uncertain and/or diverse mechanisms of action.

  9. Robustness of RISMC Insights under Alternative Aleatory/Epistemic Uncertainty Classifications: Draft Report under the Risk-Informed Safety Margin Characterization (RISMC) Pathway of the DOE Light Water Reactor Sustainability Program

    SciTech Connect

    Unwin, Stephen D.; Eslinger, Paul W.; Johnson, Kenneth I.

    2012-09-20

    The Risk-Informed Safety Margin Characterization (RISMC) pathway is a set of activities defined under the U.S. Department of Energy (DOE) Light Water Reactor Sustainability Program. The overarching objective of RISMC is to support plant life-extension decision-making by providing a state-of-knowledge characterization of safety margins in key systems, structures, and components (SSCs). A technical challenge at the core of this effort is to establish the conceptual and technical feasibility of analyzing safety margin in a risk-informed way, which, unlike conventionally defined deterministic margin analysis, would be founded on probabilistic characterizations of uncertainty in SSC performance. In the context of probabilistic risk assessment (PRA) technology, there has arisen a general consensus about the distinctive roles of two types of uncertainty: aleatory and epistemic, where the former represents irreducible, random variability inherent in a system, whereas the latter represents a state of knowledge uncertainty on the part of the analyst about the system which is, in principle, reducible through further research. While there is often some ambiguity about how any one contributing uncertainty in an analysis should be classified, there has nevertheless emerged a broad consensus on the meanings of these uncertainty types in the PRA setting. However, while RISMC methodology shares some features with conventional PRA, it will nevertheless be a distinctive methodology set. Therefore, the paradigms for classification of uncertainty in the PRA setting may not fully port to the RISMC environment. Yet the notion of risk-informed margin is based on the characterization of uncertainty, and it is therefore critical to establish a common understanding of uncertainty in the RISMC setting.

  10. RISK AND RISK ASSESSMENT IN WATER-BASED RECREATION

    EPA Science Inventory

    The great number of individuals using recreational water resources presents a challenge with regard to protecting the health of these recreationists. Risk assessment provides a framework for characterizing the risk associated with exposure to microbial hazards and for managing r...