Science.gov

Sample records for exposure comparative analysis

  1. Comparative analysis of UVB exposure between Nimbus 7/TOMS satellite estimates and ground-based measurements

    NASA Astrophysics Data System (ADS)

    Gao, Zhiqiang; Gao, Wei

    2010-08-01

    This study describes the patterns of variation in ultraviolet (UV) exposure across time and space using two continental scale data sets on UV radiation and conducts a comparative analysis of two sources of noontime UV-B exposure data across the continental US. One dataset was collected from 37 ground-based stations equipped with broadband UV-B-1 Pyranometers across North America whereas the other dataset was of synchronous satellite data collected from the Nimbus-7/TOMS sensor. Comparisons of these datasets confirmed agreement between the ground-based measurements and the TOMS satellite estimates with correlation coefficients of 0.87 and 0.95 for daily and monthly UV Index time series (i.e., a common metric of UV radiation exposure), respectively.

  2. A comparative immunological analysis of CoCl2 treated cells with in vitro hypoxic exposure.

    PubMed

    Shweta; Mishra, K P; Chanda, S; Singh, S B; Ganju, L

    2015-02-01

    The hypoxic preconditioning of mammalian cells has been shown to have beneficial effects against hypoxic injuries. However, very little information is available on the comparative analysis of immunological responses to hypoxic and hypoxia mimetic exposure. Therefore, in the present study, mouse peritoneal macrophages and splenocytes were subjected to hypoxia exposure (0.5 % O2) and hypoxia mimetic Cobalt chloride (CoCl2) treatment to evaluate their effect on immune response and delineate the underlying signaling mechanisms. The results obtained indicated that super oxide generation increased while TLR4 expression and cell surface markers like CD25, CD40 and CD69 were suppressed in both the treatments as compared to normoxia. Cobalt chloride treatment increased NF-κB expression, nitric oxide (NO) and iNOS expression, cytokines TNF-α and IL-6 as compared to hypoxia exposure. Our study showed that CoCl2 stabilizes HIF-1α to create hypoxia like conditions but it mainly influences the inflammatory response via NF-κB signaling pathway by skewing the production of proinflammatory molecules like TNF-α, IL-6 and NO.

  3. SENSITIVITY ANALYSIS OF THE APPLICATION OF CHEMICAL EXPOSURE CRITERIA FOR COMPARING SITES AND WATERSHEDS

    EPA Science Inventory

    A methodology was developed for deriving quantitative exposure criteria useful for comparing a site or watershed to a reference condition. The prototype method used indicators of exposures to oil contamination and combustion by-products, naphthalene and benzo(a)pyrene metabolites...

  4. Comparing measurement error correction methods for rate-of-change exposure variables in survival analysis.

    PubMed

    Veronesi, Giovanni; Ferrario, Marco M; Chambless, Lloyd E

    2013-12-01

    In this article we focus on comparing measurement error correction methods for rate-of-change exposure variables in survival analysis, when longitudinal data are observed prior to the follow-up time. Motivational examples include the analysis of the association between changes in cardiovascular risk factors and subsequent onset of coronary events. We derive a measurement error model for the rate of change, estimated through subject-specific linear regression, assuming an additive measurement error model for the time-specific measurements. The rate of change is then included as a time-invariant variable in a Cox proportional hazards model, adjusting for the first time-specific measurement (baseline) and an error-free covariate. In a simulation study, we compared bias, standard deviation and mean squared error (MSE) for the regression calibration (RC) and the simulation-extrapolation (SIMEX) estimators. Our findings indicate that when the amount of measurement error is substantial, RC should be the preferred method, since it has smaller MSE for estimating the coefficients of the rate of change and of the variable measured without error. However, when the amount of measurement error is small, the choice of the method should take into account the event rate in the population and the effect size to be estimated. An application to an observational study, as well as examples of published studies where our model could have been applied, are also provided.

  5. Comparative international analysis of radiofrequency exposure surveys of mobile communication radio base stations.

    PubMed

    Rowley, Jack T; Joyner, Ken H

    2012-01-01

    This paper presents analyses of data from surveys of radio base stations in 23 countries across five continents from the year 2000 onward and includes over 173,000 individual data points. The research compared the results of the national surveys, investigated chronological trends and compared exposures by technology. The key findings from this data are that irrespective of country, the year and cellular technology, exposures to radio signals at ground level were only a small fraction of the relevant human exposure standards. Importantly, there has been no significant increase in exposure levels since the widespread introduction of 3G mobile services, which should be reassuring for policy makers and negate the need for post-installation measurements at ground level for compliance purposes. There may be areas close to antennas where compliance levels could be exceeded. Future potential work includes extending the study to additional countries, development of cumulative exposure distributions and investigating the possibility of linking exposure measurements to population statistics to assess the distribution of exposure levels relative to population percentiles.

  6. Comparative international analysis of radiofrequency exposure surveys of mobile communication radio base stations

    PubMed Central

    Rowley, Jack T; Joyner, Ken H

    2012-01-01

    This paper presents analyses of data from surveys of radio base stations in 23 countries across five continents from the year 2000 onward and includes over 173,000 individual data points. The research compared the results of the national surveys, investigated chronological trends and compared exposures by technology. The key findings from this data are that irrespective of country, the year and cellular technology, exposures to radio signals at ground level were only a small fraction of the relevant human exposure standards. Importantly, there has been no significant increase in exposure levels since the widespread introduction of 3G mobile services, which should be reassuring for policy makers and negate the need for post-installation measurements at ground level for compliance purposes. There may be areas close to antennas where compliance levels could be exceeded. Future potential work includes extending the study to additional countries, development of cumulative exposure distributions and investigating the possibility of linking exposure measurements to population statistics to assess the distribution of exposure levels relative to population percentiles. PMID:22377680

  7. COMPARING THE UTILITY OF MULTIMEDIA MODELS FOR HUMAN AND ECOLOGICAL EXPOSURE ANALYSIS: TWO CASES

    EPA Science Inventory

    A number of models are available for exposure assessment; however, few are used as tools for both human and ecosystem risks. This discussion will consider two modeling frameworks that have recently been used to support human and ecological decision making. The study will compare ...

  8. EXPOSURE ANALYSIS

    EPA Science Inventory

    This proceedings chapter presents the state of the science regarding the evaluation of exposure as it relates to WQC, SQGs, and wildlife criteria (WC). . . . In summary, the exposure workgroup concluded the following: There should be greater use of mechanistic models to predict b...

  9. EXPOSURE ANALYSIS

    EPA Science Inventory

    This proceedings chapter will discuss the state-of-the-science regarding the evaluation of exposure as it relates to water quality criteria (WQC), sediment quality guidelines (SQG), and wildlife criteria (WC). Throughout this discussion, attempts are made to identify the methods ...

  10. Comparative Analysis of Immune Cells Activation and Cytotoxicity upon Exposure Pathogen and Glycoconjugates

    NASA Astrophysics Data System (ADS)

    Saheb, Entsar; Tarasenko, Olga

    2010-04-01

    Peripheral mononuclear cells (PMNC) including macrophages are key players in the immune responses against pathogens. Any infection could be attenuated if PMNC would be activated and capable to kill pathogen on exposure. It was shown that glycoconjugates (GCs) play an important role in adhesion to, activation, and recognition of pathogens. Nitric oxide (NO) is a regulatory molecule released by immune cells against pathogens that include bacteria, protozoa, helminthes, and fungi. NO is a highly reactive and diffusible molecule that controls replication or intracellular killing of pathogens during infection and immune responses against infections caused by pathogens. Avirulent Bacillus anthracis Sterne spores were used as a model in our study. The purpose of this study was two-fold: A) to analyze PMNC activation through NO production and B) to determine the cytotoxicity effect based on lactate dehydrogenase (LDH) upon exposure to pathogen exerted by GCs. The latter were used "prior to," "during," and "following" PMNC exposure to pathogen in order to modulate immune responses to spores during phagocytosis. Post-phagocytosis study involved the assessment of NO and LDH release by macrophages upon exposure to spores. Results have shown that untreated PMNC released low levels of NO. However, in the presence of GCs, PMNC were activated and produced high levels of NO under all experimental conditions. In addition, the results showed that GC1, GC3 are capable of increasing PMNC activity as evidenced by higher NO levels under the "prior," "during" and "following" to pathogen exposure conditions. On the other hand, GCs were capable of controlling cytotoxicity and decreased LDH levels during phagocytosis of spores. Our findings suggest that GCs stimulate NO production by activating PMNC and decrease cytotoxicity caused by pathogens on PMNC.

  11. Comparative Analysis of Airborne Chemical Exposure to Air Force Small Arms Range Instructors

    DTIC Science & Technology

    2006-03-01

    pressures and heart irregularities (USDHHS, 1992). An animal study involving guinea pigs documented in 1986 showed similar cardiovascular effects (USDHHS...hormones (above 4.5 milli-international units per liter for adults) can lead to thyroid failure and may ultimately affect all body functions ( Nissl ...Bioenvironmental Engineering Flights dating back to 1986 . Results indicate eight-hour TWA lead exposures directly associated with M16 firing operations at

  12. Comparative Analysis.

    DTIC Science & Technology

    1987-11-01

    Al" 56 COMPARATIVE ANALYSIS(U) MASSACJWSETTS INST OF TECH 1/1 CAMBRIDGE ARTIFICIAL INTELLIGENCE LAO 9 S MELD NOV B, RI-N-95i NMM4-85-K-0124...0 0 0 0 0 0 i. -~~ --- WU V1 2 fwx~, - - W-na alc F!LFI MASSACHUSETTS INSTITUTE OF TECHNOLOGY CO ARTIFICIAL INTELLIGENCE LABORATORY Lfl 0 Al/Memo...differential qualita- tive (DQ) analysis, which solves the task, providing explanations suitable for use by design systems, automated diagnosis, intelligent

  13. Comparative toxicogenomic analysis of oral Cr(VI) exposure effects in rat and mouse small intestinal epithelia

    SciTech Connect

    Kopec, Anna K.; Thompson, Chad M.; Kim, Suntae; Forgacs, Agnes L.; Zacharewski, Timothy R.

    2012-07-15

    Continuous exposure to high concentrations of hexavalent chromium [Cr(VI)] in drinking water results in intestinal tumors in mice but not rats. Concentration-dependent gene expression effects were evaluated in female F344 rat duodenal and jejunal epithelia following 7 and 90 days of exposure to 0.3–520 mg/L (as sodium dichromate dihydrate, SDD) in drinking water. Whole-genome microarrays identified 3269 and 1815 duodenal, and 4557 and 1534 jejunal differentially expressed genes at 8 and 91 days, respectively, with significant overlaps between the intestinal segments. Functional annotation identified gene expression changes associated with oxidative stress, cell cycle, cell death, and immune response that were consistent with reported changes in redox status and histopathology. Comparative analysis with B6C3F1 mouse data from a similarly designed study identified 2790 differentially expressed rat orthologs in the duodenum compared to 5013 mouse orthologs at day 8, and only 1504 rat and 3484 mouse orthologs at day 91. Automated dose–response modeling resulted in similar median EC{sub 50}s in the rodent duodenal and jejunal mucosae. Comparative examination of differentially expressed genes also identified divergently regulated orthologs. Comparable numbers of differentially expressed genes were observed at equivalent Cr concentrations (μg Cr/g duodenum). However, mice accumulated higher Cr levels than rats at ≥ 170 mg/L SDD, resulting in a ∼ 2-fold increase in the number of differentially expressed genes. These qualitative and quantitative differences in differential gene expression, which correlate with differences in tissue dose, likely contribute to the disparate intestinal tumor outcomes. -- Highlights: ► Cr(VI) elicits dose-dependent changes in gene expression in rat intestine. ► Cr(VI) elicits less differential gene expression in rats compared to mice. ► Cr(VI) gene expression can be phenotypically anchored to intestinal changes. ► Species

  14. Comparative systems toxicology analysis of cigarette smoke and aerosol from a candidate modified risk tobacco product in organotypic human gingival epithelial cultures: A 3-day repeated exposure study.

    PubMed

    Zanetti, Filippo; Titz, Bjoern; Sewer, Alain; Lo Sasso, Giuseppe; Scotti, Elena; Schlage, Walter K; Mathis, Carole; Leroy, Patrice; Majeed, Shoaib; Torres, Laura Ortega; Keppler, Brian R; Elamin, Ashraf; Trivedi, Keyur; Guedj, Emmanuel; Martin, Florian; Frentzel, Stefan; Ivanov, Nikolai V; Peitsch, Manuel C; Hoeng, Julia

    2017-03-01

    Smoking is one of the major lifestyle-related risk factors for periodontal diseases. Modified risk tobacco products (MRTP) offer a promising alternative in the harm reduction strategy for adult smokers unable to quit. Using a systems toxicology approach, we investigated and compared the exposure effects of a reference cigarette (3R4F) and a heat-not-burn technology-based candidate MRTP, the Tobacco Heating System (THS) 2.2. Human gingival epithelial organotypic cultures were repeatedly exposed (3 days) for 28 min at two matching concentrations of cigarette smoke (CS) or THS2.2 aerosol. Results showed only minor histopathological alterations and minimal cytotoxicity upon THS2.2 aerosol exposure compared to CS (1% for THS2.2 aerosol vs. 30% for CS, at the high concentration). Among the 14 proinflammatory mediators analyzed, only 5 exhibited significant alterations with THS2.2 exposure compared with 11 upon CS exposure. Transcriptomic and metabolomic analysis indicated a general reduction of the impact in THS2.2 aerosol-exposed samples with respect to CS (∼79% lower biological impact for the high THS2.2 aerosol concentration compared to CS, and 13 metabolites significantly perturbed for THS2.2 vs. 181 for CS). This study indicates that exposure to THS2.2 aerosol had a lower impact on the pathophysiology of human gingival organotypic cultures than CS.

  15. Comparing prediction models for radiographic exposures

    NASA Astrophysics Data System (ADS)

    Ching, W.; Robinson, J.; McEntee, M. F.

    2015-03-01

    During radiographic exposures the milliampere-seconds (mAs), kilovoltage peak (kVp) and source-to-image distance can be adjusted for variations in patient thicknesses. Several exposure adjustment systems have been developed to assist with this selection. This study compares the accuracy of four systems to predict the required mAs for pelvic radiographs taken on a direct digital radiography system (DDR). Sixty radiographs were obtained by adjusting mAs to compensate for varying combinations of source-to-image distance (SID), kVp and patient thicknesses. The 25% rule, the DuPont Bit System and the DigiBit system were compared to determine which of these three most accurately predicted the mAs required for an increase in patient thickness. Similarly, the 15% rule, the DuPont Bit System and the DigiBit system were compared for an increase in kVp. The exposure index (EI) was used as an indication of exposure to the DDR. For each exposure combination the mAs was adjusted until an EI of 1500+/-2% was achieved. The 25% rule was the most accurate at predicting the mAs required for an increase in patient thickness, with 53% of the mAs predictions correct. The DigiBit system was the most accurate at predicting mAs needed for changes in kVp, with 33% of predictions correct. This study demonstrated that the 25% rule and DigiBit system were the most accurate predictors of mAs required for an increase in patient thickness and kVp respectively. The DigiBit system worked well in both scenarios as it is a single exposure adjustment system that considers a variety of exposure factors.

  16. Comparative Analysis of Stress Induced Gene Expression in Caenorhabditis elegans following Exposure to Environmental and Lab Reconstituted Complex Metal Mixture

    PubMed Central

    Kumar, Ranjeet; Pradhan, Ajay; Khan, Faisal Ahmad; Lindström, Pia; Ragnvaldsson, Daniel; Ivarsson, Per; Olsson, Per-Erik; Jass, Jana

    2015-01-01

    Metals are essential for many physiological processes and are ubiquitously present in the environment. However, high metal concentrations can be harmful to organisms and lead to physiological stress and diseases. The accumulation of transition metals in the environment due to either natural processes or anthropogenic activities such as mining results in the contamination of water and soil environments. The present study used Caenorhabditis elegans to evaluate gene expression as an indicator of physiological response, following exposure to water collected from three different locations downstream of a Swedish mining site and a lab reconstituted metal mixture. Our results indicated that the reconstituted metal mixture exerted a direct stress response in C. elegans whereas the environmental waters elicited either a diminished or abrogated response. This suggests that it is not sufficient to use the biological effects observed from laboratory mixtures to extrapolate the effects observed in complex aquatic environments and apply this to risk assessment and intervention. PMID:26168046

  17. Comparative Analysis of Differentially Expressed Genes in Shewanella oneidensis MR-1 following Exposure to UVC, UVB, and UVA Radiation†

    PubMed Central

    Qiu, Xiaoyun; Sundin, George W.; Wu, Liyou; Zhou, Jizhong; Tiedje, James M.

    2005-01-01

    We previously reported that Shewanella oneidensis MR-1 is highly sensitive to UVC (254 nm), UVB (290 to 320 nm), and UVA (320 to 400 nm). Here we delineated the cellular response of MR-1 to UV radiation damage by analyzing the transcriptional profile during a 1-h recovering period after UVC, UVB, and UVA exposure at a dose that yields about a 20% survival rate. Although the SOS response was observed with all three treatments, the induction was more robust in response to short-wavelength UV radiation (UVB and UVC). Similarly, more prophage-related genes were induced by short-wavelength UV radiation. MR-1 showed an active detoxification mechanism in response to UVA, which included the induction of antioxidant enzymes and iron-sequestering proteins to scavenge reactive oxygen species. In addition, a great number of genes encoding multidrug and heavy metal efflux pumps were induced following UVA irradiation. Our data suggested that activation of prophages appears the major lethal factor in MR-1 following UVC or UVB irradiation, whereas oxidative damage contributes greatly to the high UVA sensitivity in MR-1. PMID:15866945

  18. Comparability of portable nanoparticle exposure monitors.

    PubMed

    Asbach, Christof; Kaminski, Heinz; von Barany, Daniel; Kuhlbusch, Thomas A J; Monz, Christian; Dziurowitz, Nico; Pelzer, Johannes; Vossen, Katja; Berlin, Knut; Dietrich, Silvio; Götz, Uwe; Kiesling, Heinz-Jürgen; Schierl, Rudolf; Dahmann, Dirk

    2012-07-01

    Five different portable instrument types to monitor exposure to nanoparticles were subject to an intensive intercomparison measurement campaign. Four of them were based on electrical diffusion charging to determine the number concentration or lung deposited surface area (LDSA) concentration of airborne particles. Three out of these four also determined the mean particle size. The fifth instrument type was a handheld condensation particle counter (CPC). The instruments were challenged with three different log-normally distributed test aerosols with modal diameters between 30 and 180 nm, varying in particle concentration and morphology. The CPCs showed the highest comparability with deviations on the order of only ±5%, independent of the particle sizes, but with a strictly limited upper number concentration. The diffusion charger-based instruments showed comparability on the order of ±30% for number concentration, LDSA concentration, and mean particle size, when the specified particle size range of the instruments matched the size range of the aerosol particles, whereas significant deviations were found when a large amount of particles exceeded the upper or lower detection limit. In one case the reported number concentration was even increased by a factor of 6.9 when the modal diameter of the test aerosol exceeded the specified upper limit of the instrument. A general dependence of the measurement accuracy of all devices on particle morphology was not detected.

  19. Comparative personal exposures to organic dusts and endotoxin.

    PubMed

    Simpson, J C; Niven, R M; Pickering, C A; Oldham, L A; Fletcher, A M; Francis, H C

    1999-02-01

    The aims of the study were to provide valid comparative data for personal exposures to dust and endotoxins for different occupations and to calculate comparative data for the contamination of organic dusts with endotoxin. Nine different occupational settings were studied, drawn from the textile, agricultural and animal handling industries. Samples were collected by personal sampling techniques, using the Institute of Occupational Medicine (IOM) sampling head, glass fibre filters and rechargeable sampling pumps. The dust exposures were calculated by gravimetric analysis and using the calculated volume of air sampled were expressed as mg/m3. Endotoxin exposures were measured using a simple water extraction from the collected dusts, followed by a quantitative turbidimetric assay. Results were expressed as ng/m3, using the calculated volume of air sampled. In addition, the levels of the contamination of dusts with endotoxin for individual industries were expressed as ng/mg of collected dust. Two hundred and fifty-nine samples, collected from 9 different industries and across 36 different sites were analysed. This represented a sampling rate of 25% for the total work force. The average sampling time was 4.62 h. For all the dusts collected, a significant correlation between the collected dust and endotoxin was seen (r = 0.7 and p < 0.001). The highest dust exposures occurred during cleaning activities (grain handling: 72.5 mg/m3). The individuals exposed to the highest median level of dust and endotoxin were the animal handlers (poultry handlers, dust: 11.53 mg/m3, endotoxin: 71,995 ng/m3). Weaving and mushroom cultivation had the lowest exposures for dust and endotoxins. The mostly highly contaminated dusts (median values expressed as ng of endotoxin per mg of collected dust) were found in the animal handling (poultry: 1,030 ng/mg, swine: 152 ng/mg) and cotton spinning (522 ng/mg) industries. Processing of cotton and wool fibres was found to reduce the levels of

  20. Personal pollen exposure compared to stationary measurements.

    PubMed

    Riediker, M; Keller, S; Wüthrich, B; Koller, T; Monn, C

    2000-01-01

    The aim of this study was to examine to what extent stationary outdoor pollen measurements are representative for estimating personal exposure to pollen. Ten subjects were studied during a total of 36 days in spring and summer Pollen was sampled using personal SKC total dust samplers and stationary Burkard pollen traps. The personal activity pattern was recorded quarter-hourly as well as the time spent outdoors. As a reference, SKC and Burkard samplers were run stationary and in parallel. Stationary comparison of the samplers showed good correlation (r = 0.981, p <0.001). However, the SKC sampler collected systematically about four times less pollen than the Burkard sampler. Taking into account the systematic difference between the sampling devices, the personal exposure data were about 30% of the stationary pollen concentrations with significant correlation (log-transformed data, r = 0.719, p <0.0001). Considering the average time the subjects spent outdoors (14% of sampling time), the indoor-outdoor ratio for pollen was 0.2. In conclusion, pollen reports are reliable for estimating personal exposure over a limited time period although personal pollen exposure is much lower.

  1. THE INFLUENCE OF HUMAN ACTIVITY PATTERNS ON PERSONAL PM EXPOSURE: A COMPARATIVE ANALYSIS OF FILTER-BASED AND CONTINUOUS PARTICLE MEASUREMENTS

    EPA Science Inventory

    Particulate matter (PM) exposure data from the U.S. Environmental Protection Agency sponsored 1998 Baltimore and 1999 Fresno PM Exposure Studies were analyzed to identify important microenvironments and activities that may lead to increased particle exposure for select elderly ...

  2. Comparative analysis of acid resistance in Listeria monocytogenes and Salmonella enterica strains before and after exposure to poultry decontaminants. Role of the glutamate decarboxylase (GAD) system.

    PubMed

    Alonso-Hernando, Alicia; Alonso-Calleja, Carlos; Capita, Rosa

    2009-12-01

    Data on the ability of chemical poultry decontaminants to induce an acid stress response in pathogenic bacteria are lacking. This study was undertaken in order to compare the survival rates in acid broths of Listeria monocytogenes and Salmonella enterica strains, both exposed to and not exposed to decontaminants. The contribution of the glutamate decarboxylase (GAD) acid resistance system to the survival of bacteria in acid media was also examined. Four strains (L. monocytogenes serovar 1/2, L. monocytogenes serovar 4b, S. enterica serotype Typhymurium and S. enterica serotype Enteritidis) were tested before (control) and after exposure to trisodium phosphate, acidified sodium chlorite, citric acid, chlorine dioxide and peroxyacids (strains were repeatedly passed through media containing increasing concentrations of a compound). Stationary-phase cells (10(8) cfu/ml) were inoculated into tryptic soy broth (TSB) acidified with citric acid (pH 2.7 and 5.0) with or without glutamate (10 mM) added, and incubated at 37 degrees C for 15 min. Survival percentages (calculated from viable colonies) varied from 2.47 +/- 0.67% to 91.93 +/- 5.83%. L. monocytogenes cells previously exposed to acid decontaminants (citric acid and peroxyacids) showed, when placed in acid TSB, a higher (P < 0.05) percentage of survival (average 38.80 +/- 30.52%) than control and pre-exposed to non-acidic decontaminants strains (22.82 +/- 23.80%). Similar (P > 0.05) survival percentages were observed in previously exposed to different decontaminants and control Salmonella strains. The GAD acid resistance system did not apparently play any role in the survival of L. monocytogenes or S. enterica at a low pH. This study demonstrates for the first time that prior exposure to acidic poultry decontaminants increases the percentage of survival of L. monocytogenes exposed to severe acid stress. These results have important implications for the meat industry when considering which decontaminant treatment to

  3. Farmworker Exposure to Pesticides: Methodologic Issues for the Collection of Comparable Data

    PubMed Central

    Arcury, Thomas A.; Quandt, Sara A.; Barr, Dana B.; Hoppin, Jane A.; McCauley, Linda; Grzywacz, Joseph G.; Robson, Mark G.

    2006-01-01

    The exposure of migrant and seasonal farmworkers and their families to agricultural and residential pesticides is a continuing public health concern. Pesticide exposure research has been spurred on by the development of sensitive and reliable laboratory techniques that allow the detection of minute amounts of pesticides or pesticide metabolites. The power of research on farmworker pesticide exposure has been limited because of variability in the collection of exposure data, the predictors of exposure considered, the laboratory procedures used in analyzing the exposure, and the measurement of exposure. The Farmworker Pesticide Exposure Comparable Data Conference assembled 25 scientists from diverse disciplinary and organizational backgrounds to develop methodologic consensus in four areas of farmworker pesticide exposure research: environmental exposure assessment, biomarkers, personal and occupational predictors of exposure, and health outcomes of exposure. In this introduction to this mini-monograph, first, we present the rationale for the conference and its organization. Second, we discuss some of the important challenges in conducting farmworker pesticide research, including the definition and size of the farmworker population, problems in communication and access, and the organization of agricultural work. Third, we summarize major findings from each of the conference’s four foci—environmental exposure assessment, biomonitoring, predictors of exposure, and health outcomes of exposure—as well as important laboratory and statistical analysis issues that cross-cut the four foci. PMID:16759996

  4. Theories of Comparative Analysis

    DTIC Science & Technology

    1988-05-01

    model of a projectile fired from a cannon in a uniform gravitational field serves to demonstrate the problems due to qualitative arithmetic. Nei...recently demonstrated the qualitative Gauss rule, a type of algebraic manip- ulation that is solution preserving. While it cannot eliminate all...projectile fired from a cannon illustrates this point. Given an increase in muzzle velocity, Vft, as a perturbation, DQ " analysis predicts that apogee

  5. Critique of "An Analysis of the Blast Overpressure Study Data Comparing Three Exposure Criteria," by Murphy, Khan, and Shaw

    DTIC Science & Technology

    2010-08-01

    fits the AS data set and the criterion level that has been reported to fit for small arms fire (about 85-dB LAEQ8) ( Dancer , 2000; Price, 2007). The...Hodge, D. C.; Garinther, G. R.; Rice, C. Hazardous Exposure to Impulse Noise. J. Acoust. Soc. Am. 1968, 43, 336–343. Dancer , A. Proposal for a...FRANCE 1 FRENCH-GERMAN RESEARCH INSTITUTE OF SAINT LOUIS A DANCER POBOX 70034 F-68301 SAINT LOUIS CEDEX FRANCE 1 CAPTAIN-COMMANDER

  6. Comparative analysis of bacterial community-metagenomics in coastal Gulf of Mexico sediment microcosms following exposure to Macondo oil (MC252).

    PubMed

    Koo, Hyunmin; Mojib, Nazia; Thacker, Robert W; Bej, Asim K

    2014-11-01

    The indigenous bacterial communities in sediment microcosms from Dauphin Island (DI), Petit Bois Island (PB) and Perdido Pass (PP) of the coastal Gulf of Mexico were compared following treatment with Macondo oil (MC252) using pyrosequencing and culture-based approaches. After quality-based trimming, 28,991 partial 16S rRNA sequence reads were analyzed by rarefaction, confirming that analyses of bacterial communities were saturated with respect to species diversity. Changes in the relative abundances of Proteobacteria, Bacteroidetes and Firmicutes played an important role in structuring bacterial communities in oil-treated sediments. Proteobacteria were dominant in oil-treated samples, whereas Firmicutes and Bacteroidetes were either the second or the third most abundant taxa. Tenericutes, members of which are known for oil biodegradation, were detected shortly after treatment, and continued to increase in DI and PP sediments. Multivariate statistical analyses (ADONIS) revealed significant dissimilarity of bacterial communities between oil-treated and untreated samples and among locations. In addition, a similarity percentage analysis showed the contribution of each species to the contrast between untreated and oil-treated samples. PCR amplification using DNA from pure cultures of Exiguobacterium,  Pseudoalteromonas,  Halomonas and Dyadobacter, isolated from oil-treated microcosm sediments, produced amplicons similar to polycyclic aromatic hydrocarbon-degrading genes. In the context of the 2010 Macondo blowout, the results from our study demonstrated that the indigenous bacterial communities in coastal Gulf of Mexico sediment microcosms responded to the MC252 oil with altered community structure and species composition. The rapid proliferation of hydrocarbonoclastic bacteria suggests their involvement in the degradation of the spilt oil in the Gulf of Mexico ecosystem.

  7. Comparative cytogenetic analysis of bone marrow damage induced in male B6C3F1 mice by multiple exposures to gaseous 1,3-butadiene

    SciTech Connect

    Tice, R.R.; Boucher, R.; Luke, C.A.; Shelby, M.D.

    1987-01-01

    Groups of male B6C3F1 mice were exposed to ambient air or to gaseous 1,3-butadiene (BD) at 6.25, 62.5, and 625 ppm for 10 exposure days. Exposure to BD induced in bone marrow: 1) a significant increase in the frequency of chromosomal aberrations (CA); 2) a significant elevation in the frequency of sister chromatid exchanges (SCE); 3) a significant lengthening of the average generation time (AGT); 4) a significant depression in the mitotic index (MI): and, as measured in the peripheral blood, 5) a significant increase in the proportion of circulating polychromatic erythrocytes (% PCE), and 6) a significant increase in the level of micronucleated PCE (MN-PCE) and micronucleated normochromatic erythrocytes (MN-NCE). The most sensitive indicator of genotoxic damage was the frequency of SCE, followed by MN-PCE levels, and then by CA and MN-NCE frequencies. The most sensitive measure of cytotoxic damage was AGT followed by % PCE and then my MI. The extent of concordance ranged from a very good correlation between the induction of MN-PCE and the induction of SCE to the lack of a significant correlation between the depression in the MI and any other endpoint.

  8. Characterization of population exposure to organochlorines: a cluster analysis application.

    PubMed

    Guimarães, Raphael Mendonça; Asmus, Carmen Ildes Rodrigues Fróes; Burdorf, Alex

    2013-06-01

    This study aimed to show the results from a cluster analysis application in the characterization of population exposure to organochlorines through variables related to time and exposure dose. Characteristics of 354 subjects in a population exposed to organochlorine pesticides residues related to time and exposure dose were subjected to cluster analysis to separate them into subgroups. We performed hierarchical cluster analysis. To evaluate the classification accuracy, compared to intra-group and inter-group variability by ANOVA for each dimension. The aggregation strategy was accomplished by the method of Ward. It was, for the creation of clusters, variables associated with exposure and routes of contamination. The information on the estimated intake doses of compound were used to weight the values of exposure time at each of the routes, so as to obtain values proxy exposure intensity. The results showed three clusters: cluster 1 (n = 45), characteristics of greatest exposure, the cluster 2 (n = 103), intermediate exposure, and cluster 3 (n = 206), less exposure. The bivariate analyzes performed with groups that are groups showed a statistically significant difference. This study demonstrated the applicability of cluster analysis to categorize populations exposed to organochlorines and also points to the relevance of typological studies that may contribute to a better classification of subjects exposed to chemical agents, which is typical of environmental epidemiology studies to a wider understanding of etiological, preventive and therapeutic contamination.

  9. Measurement methods for human exposure analysis.

    PubMed Central

    Lioy, P J

    1995-01-01

    The general methods used to complete measurements of human exposures are identified and illustrations are provided for the cases of indirect and direct methods used for exposure analysis. The application of the techniques for external measurements of exposure, microenvironmental and personal monitors, are placed in the context of the need to test hypotheses concerning the biological effects of concern. The linkage of external measurements to measurements made in biological fluids is explored for a suite of contaminants. This information is placed in the context of the scientific framework used to conduct exposure assessment. Examples are taken from research on volatile organics and for a large scale problem: hazardous waste sites. PMID:7635110

  10. UV exposure in artificial and natural weathering: A comparative study

    NASA Astrophysics Data System (ADS)

    Heikkilä, A.; Kazadzis, S.; Meinander, O.; Vaskuri, A.; Kärhä, P.; Mylläri, V.; Syrjälä, S.; Koskela, T.

    2017-02-01

    We report on a study focusing on UV exposure conditions in three different types of chambers used for accelerated ageing of materials. The first chamber is equipped with four 300-W UVA/UVB mercury vapour lamps (Ultra-Vitalux/Osram). The second chamber uses four 40-W UVA fluorescent lamps (QUV-340/Q-Lab). The third chamber is Weather-Ometer Ci3000+ from Atlas with a 4500-W xenon arc lamp. UV irradiance prevailing in each chamber was measured using Bentham DM150 double monochromator spectroradiometer. The results were compared to measurements of solar spectral UV irradiance at Jokioinen, Finland, with a Brewer MkIII double monochromator spectrophotometer. The spectral shapes of the exposing UV radiation in the different chambers were found to notably differ from each other and from the solar UV spectrum. Both spatial inhomogeneities and temporal variability caused by various factors, like the ageing of the lamps, were detected. The effects were found to strongly depend on wavelength of the exposing UV radiation. The findings of this study underline the necessity of careful characterization of the UV exposure conditions provided by the facilities used in accelerated testing of materials.

  11. Tsunamis: Global Exposure and Local Risk Analysis

    NASA Astrophysics Data System (ADS)

    Harbitz, C. B.; Løvholt, F.; Glimsdal, S.; Horspool, N.; Griffin, J.; Davies, G.; Frauenfelder, R.

    2014-12-01

    The 2004 Indian Ocean tsunami led to a better understanding of the likelihood of tsunami occurrence and potential tsunami inundation, and the Hyogo Framework for Action (HFA) was one direct result of this event. The United Nations International Strategy for Disaster Risk Reduction (UN-ISDR) adopted HFA in January 2005 in order to reduce disaster risk. As an instrument to compare the risk due to different natural hazards, an integrated worldwide study was implemented and published in several Global Assessment Reports (GAR) by UN-ISDR. The results of the global earthquake induced tsunami hazard and exposure analysis for a return period of 500 years are presented. Both deterministic and probabilistic methods (PTHA) are used. The resulting hazard levels for both methods are compared quantitatively for selected areas. The comparison demonstrates that the analysis is rather rough, which is expected for a study aiming at average trends on a country level across the globe. It is shown that populous Asian countries account for the largest absolute number of people living in tsunami prone areas, more than 50% of the total exposed people live in Japan. Smaller nations like Macao and the Maldives are among the most exposed by population count. Exposed nuclear power plants are limited to Japan, China, India, Taiwan, and USA. On the contrary, a local tsunami vulnerability and risk analysis applies information on population, building types, infrastructure, inundation, flow depth for a certain tsunami scenario with a corresponding return period combined with empirical data on tsunami damages and mortality. Results and validation of a GIS tsunami vulnerability and risk assessment model are presented. The GIS model is adapted for optimal use of data available for each study. Finally, the importance of including landslide sources in the tsunami analysis is also discussed.

  12. HUMAN EXPOSURE ANALYSIS, AN INTERDISCIPLINARY SCIENCE

    EPA Science Inventory

    The relatively new and expanding field of human exposure analysis has its genesis in the environmental movement and the interest of scientists and the public in understanding the interaction between anthropogenic and biogenic chemicals and people. The universe is full of chemi...

  13. EXHALED BREATH ANALYSIS FOR HUMAN EXPOSURE RESEARCH

    EPA Science Inventory

    Exhaled breath collection and analysis has historically been used in environmental research studies to characterize exposures to volatile organic compounds. The use of this approach is based on the fact that many compounds present in blood are reflected in the breath, and that...

  14. Monitoring low benzene exposure: comparative evaluation of urinary biomarkers, influence of cigarette smoking, and genetic polymorphisms.

    PubMed

    Fustinoni, Silvia; Consonni, Dario; Campo, Laura; Buratti, Marina; Colombi, Antonio; Pesatori, Angela C; Bonzini, Matteo; Bertazzi, Pier A; Foà, Vito; Garte, Seymour; Farmer, Peter B; Levy, Leonard S; Pala, Mauro; Valerio, Federico; Fontana, Vincenzo; Desideri, Arianna; Merlo, Domenico F

    2005-09-01

    Benzene is a human carcinogen and an ubiquitous environmental pollutant. Identification of specific and sensitive biological markers is critical for the definition of exposure to low benzene level and the evaluation of the health risk posed by this exposure. This investigation compared urinary trans,trans-muconic acid (t,t-MA), S-phenylmercapturic acid, and benzene (U-benzene) as biomarkers to assess benzene exposure and evaluated the influence of smoking and the genetic polymorphisms CYP2E1 (RsaI and DraI) and NADPH quinone oxidoreductase-1 on these indices. Gas station attendants, urban policemen, bus drivers, and two groups of controls were studied (415 subjects). Median benzene exposure was 61, 22, 21, 9 and 6 microg/m(3), respectively, with higher levels in workers than in controls. U-benzene, but not t,t-MA and S-phenylmercapturic acid, showed an exposure-related increase. All the biomarkers were strongly influenced by cigarette smoking, with values up to 8-fold higher in smokers compared with nonsmokers. Significant correlations of the biomarkers with each other and with urinary cotinine were found. A possible influence of genetic polymorphism of CYP2E1 (RsaI and/or DraI) on t,t-MA and U-benzene in subjects with a variant allele was found. Multiple linear regression analysis correlated the urinary markers with exposure, smoking status, and CYP2E1 (RsaI; R(2) up to 0.55 for U-benzene). In conclusion, in the range of investigated benzene levels (<478 micro/m(3) or <0.15 ppm), smoking may be regarded as the major source of benzene intake; among the study indices, U-benzene is the marker of choice for biomonitoring low-level occupational and environmental benzene exposure.

  15. Comparative effect of water and food-chain mediated cadmium exposure in rats.

    PubMed

    Asagba, Samuel Ogheneovo

    2010-12-01

    This study sets out to compare the absorption and toxicity of Cadmium (Cd) administered via the food-chain and inorganic Cd administered in drinking water after 1 and 3 months exposure using rats as animal model. The food-chain was mimicked by exposing rats to diet containing Cd pre-exposed fish. The uptake of Cd by the rats after both mode of exposure was calculated by summing up the Cd burden in the liver and kidneys and was expressed in terms of % intake. The toxicity of Cd was assessed by monitoring biochemical indices of liver function in the plasma and liver. Regardless of the mode of exposure of the rats, the Cd load in the liver and kidney was significantly (P < 0.05) higher than the respective controls with the kidney having a significantly higher load than the liver after both periods of exposure. However irrespective of the mode of exposure, more Cd was accumulated in the liver and kidney of the 3 months exposed rats relative to those exposed for 1 month. The uptake of Cd by rats exposed to Cd via the food-chain for 1 and 3 months was significantly (P < 0.05) lower when compared to the corresponding water mediated Cd exposed rats, except for the liver after 3 months of exposure. The liver L-ALT activity of rats administered inorganic Cd in drinking water for 1 and 3 months was significantly (P < 0.05) lower as compared to controls. Parallel analysis of the plasma showed no significant (P > 0.05) difference in L-ALT activity between both groups after the same periods of exposure. The L-AST activity in the plasma of rats similarly exposed to Cd for 1 and 3 months was significantly (P < 0.05) higher as compared to controls with a corresponding reduction in the liver. Conversely no significant (P > 0.05) change was observed in plasma and liver L-ALT and L-AST activities after food-chain mediated exposure to Cd for 1 and 3 months in relation to their respective controls. These findings indicate that Cd incorporated in fish is more easily bioavailable, but

  16. 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

  17. Comparative analysis of collaboration networks

    SciTech Connect

    Progulova, Tatiana; Gadjiev, Bahruz

    2011-03-14

    In this paper we carry out a comparative analysis of the word network as the collaboration network based on the novel by M. Bulgakov 'Master and Margarita', the synonym network of the Russian language as well as the Russian movie actor network. We have constructed one-mode projections of these networks, defined degree distributions for them and have calculated main characteristics. In the paper a generation algorithm of collaboration networks has been offered which allows one to generate networks statistically equivalent to the studied ones. It lets us reveal a structural correlation between word network, synonym network and movie actor network. We show that the degree distributions of all analyzable networks are described by the distribution of q-type.

  18. Comparative analysis of collaboration networks

    NASA Astrophysics Data System (ADS)

    Progulova, Tatiana; Gadjiev, Bahruz

    2011-03-01

    In this paper we carry out a comparative analysis of the word network as the collaboration network based on the novel by M. Bulgakov "Master and Margarita", the synonym network of the Russian language as well as the Russian movie actor network. We have constructed one-mode projections of these networks, defined degree distributions for them and have calculated main characteristics. In the paper a generation algorithm of collaboration networks has been offered which allows one to generate networks statistically equivalent to the studied ones. It lets us reveal a structural correlation between word network, synonym network and movie actor network. We show that the degree distributions of all analyzable networks are described by the distribution of q-type.

  19. Comparing Virtual Reality Exposure Therapy to Prolonged Exposure in the Treatment of Soldiers with PTSD

    DTIC Science & Technology

    2014-06-01

    researched psychotherapies for PTSD. Virtual reality exposure (VRE) has demonstrated growing support as an innovative method for activating the trauma...related trauma that met criteria for PTSD according to the CAPS. Participants also had to agree not to initiate other psychotherapy for PTSD or new...1. Psychotherapy that used prolonged or virtual reality-enhanced prolonged exposure (VR) would reduce the clinical symptoms of PTSD to a greater

  20. Skin analysis following dermal exposure to kerosene in rats: the effects of postmortem exposure and fire.

    PubMed

    Hieda, Yoko; Tsujino, Yoshio; Xue, Yuying; Takayama, Koji; Fujihara, Junko; Kimura, Kojiro; Dekio, Satoshi

    2004-02-01

    To evaluate the usefulness of skin analysis for the forensic examination of cases involving postmortem dermal exposure to kerosene and/or fire, an experimental study using rats was performed. Rats received dermal exposure to kerosene before or after death, and the effect of fire was determined by burning an area of exposed skin after death. Kerosene concentrations in skin and blood were determined by gas chromatography-mass spectrometry and microscopic observation was performed for skin samples. No differences were observed in skin kerosene levels between antemortem and postmortem exposure. Kerosene concentrations in mildly burned skin where the stratum corneum (SC) was retained were approximately 84% compared to those in non-burned exposed skin, whereas concentrations in severely burned skin where the SC was almost completely burned off were 28% of non-burned skin. Even in non-exposed control skin 14% of the original kerosene concentrations could be detected, which was considered to be caused by contamination during the experimental protocol combined with kerosene's property of a high affinity for the SC. These results suggest that (1) skin analysis is useful in estimating the type of petroleum product involved in crimes or accidents even for postmortem exposure, (2) whether the SC is retained or not primarily determined the kerosene levels in burned skin, and (3) attention must be paid to evaluate the results obtained from skin samples in the light of the circumstances surrounding the case.

  1. Technical Overview of Ecological Risk Assessment - Analysis Phase: Exposure Characterization

    EPA Pesticide Factsheets

    Exposure Characterization is the second major component of the analysis phase of a risk assessment. For a pesticide risk assessment, the exposure characterization describes the potential or actual contact of a pesticide with a plant, animal, or media.

  2. EXPOSURE ANALYSIS MODELING SYSTEM (EXAMS): USER MANUAL AND SYSTEM DOCUMENTATION

    EPA Science Inventory

    The Exposure Analysis Modeling System, first published in 1982 (EPA-600/3-82-023), provides interactive computer software for formulating aquatic ecosystem models and rapidly evaluating the fate, transport, and exposure concentrations of synthetic organic chemicals - pesticides, ...

  3. ALVEOLAR BREATH SAMPLING AND ANALYSIS IN HUMAN EXPOSURE ASSESSMENT STUDIES

    EPA Science Inventory

    Alveolar breath sampling and analysis can be extremely useful in exposure assessment studies involving volatile organic compounds (VOCs). Over recent years scientists from the EPA's National Exposure Research Laboratory have developed and refined an alveolar breath collection ...

  4. Sociological analysis and comparative education

    NASA Astrophysics Data System (ADS)

    Woock, Roger R.

    1981-12-01

    It is argued that comparative education is essentially a derivative field of study, in that it borrows theories and methods from academic disciplines. After a brief humanistic phase, in which history and philosophy were central for comparative education, sociology became an important source. In the mid-50's and 60's, sociology in the United States was characterised by Structural Functionalism as a theory, and Social Survey as a dominant methodology. Both were incorporated into the development of comparative education. Increasingly in the 70's, and certainly today, the new developments in sociology are characterised by an attack on Positivism, which is seen as the philosophical position underlying both functionalism and survey methods. New or re-discovered theories with their attendant methodologies included Marxism, Phenomenological Sociology, Critical Theory, and Historical Social Science. The current relationship between comparative education and social science is one of uncertainty, but since social science is seen to be returning to its European roots, the hope is held out for the development of an integrated social theory and method which will provide a much stronger basis for developments in comparative education.

  5. Auditory Effects of Exposure to Noise and Solvents: A Comparative Study

    PubMed Central

    Lobato, Diolen Conceição Barros; Lacerda, Adriana Bender Moreira De; Gonçalves, Cláudia Giglio De Oliveira; Coifman, Herton

    2013-01-01

    Introduction Industry workers are exposed to different environmental risk agents that, when combined, may potentiate risks to hearing. Objective To evaluate the effects of the combined exposure to noise and solvents on hearing in workers. Methods A transversal retrospective cohort study was performed through documentary analysis of an industry. The sample (n = 198) was divided into four groups: the noise group (NG), exposed only to noise; the noise and solvents group (NSG), exposed to noise and solvents; the noise control group and noise and solvents control group (CNS), no exposure. Results The NG showed 16.66% of cases suggestive of bilateral noise-induced hearing loss and NSG showed 5.26%. The NG and NSG had worse thresholds than their respective control groups. Females were less susceptible to noise than males; however, when simultaneously exposed to solvents, hearing was affected in a similar way, resulting in significant differences (p < 0.05). The 40- to 49-year-old age group was significantly worse (p < 0.05) in the auditory thresholds in the NSG compared with the CNS. Conclusion The results observed in this study indicate that simultaneous exposure to noise and solvents can damage the peripheral auditory system. PMID:25992079

  6. Comparing children's GPS tracks with geospatial proxies for exposure to junk food.

    PubMed

    Sadler, Richard C; Gilliland, Jason A

    2015-01-01

    Various geospatial techniques have been employed to estimate children's exposure to environmental cardiometabolic risk factors, including junk food. But many studies uncritically rely on exposure proxies which differ greatly from actual exposure. Misrepresentation of exposure by researchers could lead to poor decisions and ineffective policymaking. This study conducts a GIS-based analysis of GPS tracks--'activity spaces'--and 21 proxies for activity spaces (e.g. buffers, container approaches) for a sample of 526 children (ages 9-14) in London, Ontario, Canada. These measures are combined with a validated food environment database (including fast food and convenience stores) to create a series of junk food exposure estimates and quantify the errors resulting from use of different proxy methods. Results indicate that exposure proxies consistently underestimate exposure to junk foods by as much as 68%. This underestimation is important to policy development because children are exposed to more junk food than estimated using typical methods.

  7. Advancing Exposure Science through Chemical Data Curation and Integration in the Comparative Toxicogenomics Database

    PubMed Central

    Grondin, Cynthia J.; Davis, Allan Peter; Wiegers, Thomas C.; King, Benjamin L.; Wiegers, Jolene A.; Reif, David M.; Hoppin, Jane A.; Mattingly, Carolyn J.

    2016-01-01

    Background: Exposure science studies the interactions and outcomes between environmental stressors and human or ecological receptors. To augment its role in understanding human health and the exposome, we aimed to centralize and integrate exposure science data into the broader biological framework of the Comparative Toxicogenomics Database (CTD), a public resource that promotes understanding of environmental chemicals and their effects on human health. Objectives: We integrated exposure data within the CTD to provide a centralized, freely available resource that facilitates identification of connections between real-world exposures, chemicals, genes/proteins, diseases, biological processes, and molecular pathways. Methods: We developed a manual curation paradigm that captures exposure data from the scientific literature using controlled vocabularies and free text within the context of four primary exposure concepts: stressor, receptor, exposure event, and exposure outcome. Using data from the Agricultural Health Study, we have illustrated the benefits of both centralization and integration of exposure information with CTD core data. Results: We have described our curation process, demonstrated how exposure data can be accessed and analyzed in the CTD, and shown how this integration provides a broad biological context for exposure data to promote mechanistic understanding of environmental influences on human health. Conclusions: Curation and integration of exposure data within the CTD provides researchers with new opportunities to correlate exposures with human health outcomes, to identify underlying potential molecular mechanisms, and to improve understanding about the exposome. Citation: Grondin CJ, Davis AP, Wiegers TC, King BL, Wiegers JA, Reif DM, Hoppin JA, Mattingly CJ. 2016. Advancing exposure science through chemical data curation and integration in the Comparative Toxicogenomics Database. Environ Health Perspect 124:1592–1599; http://dx.doi.org/10

  8. An examination of population exposure to traffic related air pollution: Comparing spatially and temporally resolved estimates against long-term average exposures at the home location.

    PubMed

    Shekarrizfard, Maryam; Faghih-Imani, Ahmadreza; Hatzopoulou, Marianne

    2016-05-01

    Air pollution in metropolitan areas is mainly caused by traffic emissions. This study presents the development of a model chain consisting of a transportation model, an emissions model, and atmospheric dispersion model, applied to dynamically evaluate individuals' exposure to air pollution by intersecting daily trajectories of individuals and hourly spatial variations of air pollution across the study domain. This dynamic approach is implemented in Montreal, Canada to highlight the advantages of the method for exposure analysis. The results for nitrogen dioxide (NO2), a marker of traffic related air pollution, reveal significant differences when relying on spatially and temporally resolved concentrations combined with individuals' daily trajectories compared to a long-term average NO2 concentration at the home location. We observe that NO2 exposures based on trips and activity locations visited throughout the day were often more elevated than daily NO2 concentrations at the home location. The percentage of all individuals with a lower 24-hour daily average at home compared to their 24-hour mobility exposure is 89.6%, of which 31% of individuals increase their exposure by more than 10% by leaving the home. On average, individuals increased their exposure by 23-44% while commuting and conducting activities out of home (compared to the daily concentration at home), regardless of air quality at their home location. We conclude that our proposed dynamic modelling approach significantly improves the results of traditional methods that rely on a long-term average concentration at the home location and we shed light on the importance of using individual daily trajectories to understand exposure.

  9. A TIERED APPROACH TO PERFORMING UNCERTAINTY ANALYSIS IN CONDUCTING EXPOSURE ANALYSIS FOR CHEMICALS

    EPA Science Inventory

    The WHO/IPCS draft Guidance Document on Characterizing and Communicating Uncertainty in Exposure Assessment provides guidance on recommended strategies for conducting uncertainty analysis as part of human exposure analysis. Specifically, a tiered approach to uncertainty analysis ...

  10. Comparing acceptance and refusal rates of virtual reality exposure vs. in vivo exposure by patients with specific phobias.

    PubMed

    Garcia-Palacios, A; Botella, C; Hoffman, H; Fabregat, S

    2007-10-01

    The present survey explored the acceptability of virtual reality (VR) exposure and in vivo exposure in 150 participants suffering from specific phobias. Seventy-six percent chose VR over in vivo exposure, and the refusal rate for in vivo exposure (27%) was higher than the refusal rate for VR exposure (3%). Results suggest that VR exposure could help increase the number of people who seek exposure therapy for phobias.

  11. Comparing Techniques for Certified Static Analysis

    NASA Technical Reports Server (NTRS)

    Cachera, David; Pichardie, David

    2009-01-01

    A certified static analysis is an analysis whose semantic validity has been formally proved correct with a proof assistant. The recent increasing interest in using proof assistants for mechanizing programming language metatheory has given rise to several approaches for certification of static analysis. We propose a panorama of these techniques and compare their respective strengths and weaknesses.

  12. Variability in exposure to ambient ultrafine particles in urban schools: Comparative assessment between Australia and Spain.

    PubMed

    Mazaheri, Mandana; Reche, Cristina; Rivas, Ioar; Crilley, Leigh R; Álvarez-Pedrerol, Mar; Viana, Mar; Tobias, Aurelio; Alastuey, Andrés; Sunyer, Jordi; Querol, Xavier; Morawska, Lidia

    2016-03-01

    Ambient ultrafine particle number concentrations (PNC) have inhomogeneous spatio-temporal distributions and depend on a number of different urban factors, including background conditions and distant sources. This paper quantitatively compares exposure to ambient ultrafine particles at urban schools in two cities in developed countries, with high insolation climatic conditions, namely Brisbane (Australia) and Barcelona (Spain). The analysis used comprehensive indoor and outdoor air quality measurements at 25 schools in Brisbane and 39 schools in Barcelona. PNC modes were analysed with respect to ambient temperature, land use and urban characteristics, combined with the measured elemental carbon concentrations, NOx (Brisbane) and NO2 (Barcelona). The trends and modes of the quantified weekday average daily cycles of ambient PNC exhibited significant differences between the two cities. PNC increases were observed during traffic rush hours in both cases. However, the mid-day peak was dominant in Brisbane schools and had the highest contribution to total PNC for both indoors and outdoors. In Barcelona, the contribution from traffic was highest for ambient PNC, while the mid-day peak had a slightly higher contribution for indoor concentrations. Analysis of the relationships between PNC and land use characteristics in Barcelona schools showed a moderate correlation with the percentage of road network area and an anti-correlation with the percentage of green area. No statistically significant correlations were found for Brisbane. Overall, despite many similarities between the two cities, school-based exposure patterns were different. The main source of ambient PNC at schools was shown to be traffic in Barcelona and mid-day new particle formation in Brisbane. The mid-day PNC peak in Brisbane could have been driven by the combined effect of background and meteorological conditions, as well as other local/distant sources. The results have implications for urban development

  13. The Worker Exposure Failure Modes and Effects Analysis

    SciTech Connect

    Cadwallader, L.C.

    2005-05-15

    The Worker Exposure Failure Modes and Effects Analysis (WE-FMEA) is a new approach to quantitatively evaluate worker risks from possible failures of co-located equipment in the complex environment of a magnetic or inertial fusion experiment. For next-step experiments such as the International Thermonuclear Experimental Reactor (ITER) or the National Ignition Facility (NIF), the systems and equipment will be larger, handle more throughput or power, and will, in general, be more robust than past experiments. These systems and equipment are necessary to operate the machine, but the rooms are congested with equipment, piping, and cables, which poses a new level of hazard for workers who will perform hands-on maintenance. The WE-FMEA systematically analyzes the nearby equipment and the work environment for equipment failure or inherent hazards, and then develops exposure scenarios. Once identified, the exposure scenarios are evaluated for the worker hazards and quantitative worker risk is calculated. Then risk scenarios are quantitatively compared to existing statistical data on worker injuries; high-risk scenarios can be identified and addressed in more detail to determine the proper means to reduce, mitigate, or protect against the hazard. The WE-FMEA approach is described and a cooling system maintenance example is given.

  14. Cotton dust exposure: Analysis of pulmonary function and respiratory symptoms

    PubMed Central

    Dangi, Bharat M; Bhise, Anjali R

    2017-01-01

    Background: Cotton industry workers are exposed to various hazards in the different departments of textile factories. The major health problems associated with cotton dust are respiratory problems, byssinosis, bronchitis and asthma. Objective: To study the effect of cotton dust exposure on pulmonary function and respiratory symptoms. Settings and Design: This cross-sectional observational study was conducted at cotton mill in the Ahmedabad city. Materials and Methods: One hundred cotton mill workers of the weaving and spinning area participated in this study while 100 age- and gender-matched male subjects living in the residential area served as the control group. A questionnaire was used to inquire about respiratory symptoms and spirometry was done in both the groups. Statistical Analysis Used: Student's t-test was used to find the difference between spirometric parameters, and Chi-square test was used to find the difference between respiratory symptoms. Results: Respiratory symptoms were statistically significantly more common in the cotton mill workers compared to control group. Cotton mill workers group also showed significant (P < 0.0001) decrease in forced expiratory volume in 1 s (FEV1), ratio of FEV1 and forced vital capacity (FVC) and peak expiratory flow rate, and no significant difference of FVC between groups. There was an association of duration of exposure and symptoms with spirometric abnormality. Conclusion: Cotton mill workers showed a significant decrease in spirometric parameters and increase in respiratory symptoms. As the duration of exposure and symptoms increased, spirometric abnormality increased. PMID:28360462

  15. Comparative Analysis of Whole-Genome Gene Expression Changes in Cultured Human Embryonic Stem Cells in Response to Low, Clinical Diagnostic Relevant, and High Doses of Ionizing Radiation Exposure.

    PubMed

    Sokolov, Mykyta; Nguyen, Van; Neumann, Ronald

    2015-06-30

    The biological effects of low-dose ionizing radiation (LDIR) exposure in humans are not comprehensively understood, generating a high degree of controversy in published literature. The earliest stages of human development are known to be among the most sensitive to stress exposures, especially genotoxic stresses. However, the risks stemming from exposure to LDIR, particularly within the clinical diagnostic relevant dose range, have not been directly evaluated in human embryonic stem cells (hESCs). Here, we describe the dynamics of the whole genome transcriptional responses of different hESC lines to both LDIR and, as a reference, high-dose IR (HDIR). We found that even doses as low as 0.05 Gy could trigger statistically significant transient changes in a rather limited subset of genes in all hESCs lines examined. Gene expression signatures of hESCs exposed to IR appear to be highly dose-, time-, and cell line-dependent. We identified 50 genes constituting consensus gene expression signature as an early response to HDIR across all lines of hESC examined. We observed substantial differences in biological pathways affected by either LDIR or HDIR in hESCs, suggesting that the molecular mechanisms underpinning the responses of hESC may fundamentally differ depending on radiation doses.

  16. Risk analysis for worker exposure to benzene

    NASA Astrophysics Data System (ADS)

    Hallenbeck, William H.; Flowers, Roxanne E.

    1992-05-01

    Cancer risk factors (characterized by route, dose, dose rate per kilogram, fraction of lifetime exposed, species, and sex) were derived for workers exposed to benzene via inhalation or ingestion. Exposure at the current Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) and at leaking underground storage tank (LUST) sites were evaluated. At the current PEL of 1 ppm, the theoretical lifetime excess risk of cancer from benzene inhalation is ten per 1000. The theoretical lifetime excess risk for worker inhalation exposure at LUST sites ranged from 10 to 40 per 1000. These results indicate that personal protection should be required. The theoretical lifetime excess risk due to soil ingestion is five to seven orders of magnitude less than the inhalation risks.

  17. Defining Product Intake Fraction to Quantify and Compare Exposure to Consumer Products.

    PubMed

    Jolliet, Olivier; Ernstoff, Alexi S; Csiszar, Susan A; Fantke, Peter

    2015-08-04

    There is a growing consciousness that exposure studies need to better cover near-field exposure associated with products use. To consistently and quantitatively compare human exposure to chemicals in consumer products, we introduce the concept of product intake fraction, as the fraction of a chemical within a product that is eventually taken in by the human population. This metric enables consistent comparison of exposures during consumer product use for different product-chemical combinations, exposure duration, exposure routes and pathways and for other life cycle stages. We present example applications of the product intake fraction concept, for two chemicals in two personal care products and two chemicals encapsulated in two articles, showing how intakes of these chemicals can primarily occur during product use. We demonstrate the utility of the product intake fraction and its application modalities within life cycle assessment and risk assessment contexts. The product intake fraction helps to provide a clear interface between the life cycle inventory and impact assessment phases, to identify best suited sentinel products and to calculate overall exposure to chemicals in consumer products, or back-calculate maximum allowable concentrations of substances inside products.

  18. The physiological consequences of varied heat exposure events in adult Myzus persicae: a single prolonged exposure compared to repeated shorter exposures

    PubMed Central

    Andrew, Nigel R.

    2016-01-01

    The study of environmental stress tolerance in aphids has primarily been at low temperatures. In these cases, and in the rare cases of high temperature tolerance assessments, all exposures had been during a single stress event. In the present study, we examined the physiological consequences of repeated high temperature exposure with recovery periods between these stress events in Myzus persicae. We subjected individuals to either a single prolonged three hour heating event, or three one hour heating events with a recovery time of 24 h between bouts. Aphids exposed to repeated bouts of high temperatures had more glucose and higher expression of proteins and osmolyte compounds, such as glycerol, compared to the prolonged exposure group. However, aphids exposed to the repeated high temperature treatment had reduced sources of energy such as trehalose and triglyceride compounds than the prolonged exposure group. Recovery time had more physiological costs (based on production of more protein and consumption of more trehalose and triglyceride) and benefits (based on production of more osmolytes) in repeated high temperature treatments. As aphids are known to respond differently to constant versus ‘natural’ fluctuating temperature regimes, conclusions drawn from constant temperature data sets may be problematic. We suggest future experiments assessing insect responses to thermal stress incorporate a repeated stress and recovery pattern into their methodologies. PMID:27547583

  19. Comparative Environmental Threat Analysis: Three Case Studies.

    ERIC Educational Resources Information Center

    Latour, J. B.; Reiling, R.

    1994-01-01

    Reviews how carrying capacity for different environmental problems is operationalized. Discusses whether it is possible to compare threats, using the exceeding of carrying capacity as a yardstick. Points out problems in comparative threat analysis using three case studies: threats to European groundwater resources, threats to ecosystems in Europe,…

  20. Comparative Assessment of Particulate Air Pollution Exposure from Municipal Solid Waste Incinerator Emissions

    PubMed Central

    Ashworth, Danielle C.; Fuller, Gary W.; Toledano, Mireille B.; Font, Anna; Elliott, Paul; Hansell, Anna L.; de Hoogh, Kees

    2013-01-01

    Background. Research to date on health effects associated with incineration has found limited evidence of health risks, but many previous studies have been constrained by poor exposure assessment. This paper provides a comparative assessment of atmospheric dispersion modelling and distance from source (a commonly used proxy for exposure) as exposure assessment methods for pollutants released from incinerators. Methods. Distance from source and the atmospheric dispersion model ADMS-Urban were used to characterise ambient exposures to particulates from two municipal solid waste incinerators (MSWIs) in the UK. Additionally an exploration of the sensitivity of the dispersion model simulations to input parameters was performed. Results. The model output indicated extremely low ground level concentrations of PM10, with maximum concentrations of <0.01 μg/m3. Proximity and modelled PM10 concentrations for both MSWIs at postcode level were highly correlated when using continuous measures (Spearman correlation coefficients ~ 0.7) but showed poor agreement for categorical measures (deciles or quintiles, Cohen's kappa coefficients ≤ 0.5). Conclusion. To provide the most appropriate estimate of ambient exposure from MSWIs, it is essential that incinerator characteristics, magnitude of emissions, and surrounding meteorological and topographical conditions are considered. Reducing exposure misclassification is particularly important in environmental epidemiology to aid detection of low-level risks. PMID:23935644

  1. Comparative modeling of exposure to airborne nanoparticles released by consumer spray products.

    PubMed

    Riebeling, Christian; Luch, Andreas; Götz, Mario Enrico

    2016-01-01

    Consumer exposure to sprays containing nano-objects is a continuing concern as a potential health hazard. One potential hazard has been formulated in the overload hypothesis. It describes a volume fraction of the macrophages that is occupied by deposited nanoparticles that leads to reduced macrophage mobility. Subsequent chronic inflammation may then lead to severe health consequences including cancer. To calculate lung deposition of spherical particles, the Multiple-Path Particle Dosimetry (MPPD) model (ARA, Albuquerque, NM) provides different kinds of lung models and age settings. Using the MPPD v 2.11 software, we modeled several consumer-related exposure scenarios. Different body orientations and age groups were investigated. Moreover, a number of materials representing different densities were used, and the exposure calculated using MPPD is compared to the hazard derived from the overload hypothesis. Conditions leading to macrophage overload were found for exposures to high particle doses for prolonged times and repeated exposure. Such conditions are unlikely in the context of regular consumer exposure. The overload hypothesis assumes the particles to be inert and biopersistent, a condition that currently lacks a clear regulatory definition and is valid only for a few selected materials. Furthermore, because of material-specific effects and the possibility of surface adsorption of hazardous chemicals, nano-objects in propellant sprays remain of concern for consumer health.

  2. Comparing exposure metrics for classifying ‘dangerous heat’ in heat wave and health warning systems

    PubMed Central

    Zhang, Kai; Rood, Richard B.; Michailidis, George; Oswald, Evan M.; Schwartz, Joel D.; Zanobetti, Antonella; Ebi, Kristie L.; O’Neill, Marie S.

    2012-01-01

    Heat waves have been linked to excess mortality and morbidity, and are projected to increase in frequency and intensity with a warming climate. This study compares exposure metrics to trigger heat wave and health warning systems (HHWS), and introduces a novel multi-level hybrid clustering method to identify potential dangerously hot days. Two-level and three-level hybrid clustering analysis as well as common indices used to trigger HHWS, including spatial synoptic classification (SSC); and 90th, 95th, and 99th percentiles of minimum and relative minimum temperature (using a 10 day reference period), were calculated using a summertime weather dataset in Detroit from 1976 to 2006. The days classified as ‘hot’ with hybrid clustering analysis, SSC, minimum and relative minimum temperature methods differed by method type. SSC tended to include the days with, on average, 2.6 °C lower daily minimum temperature and 5.3 °C lower dew point than days identified by other methods. These metrics were evaluated by comparing their performance in predicting excess daily mortality. The 99th percentile of minimum temperature was generally the most predictive, followed by the three-level hybrid clustering method, the 95th percentile of minimum temperature, SSC and others. Our proposed clustering framework has more flexibility and requires less substantial meteorological prior information than the synoptic classification methods. Comparison of these metrics in predicting excess daily mortality suggests that metrics thought to better characterize physiological heat stress by considering several weather conditions simultaneously may not be the same metrics that are better at predicting heat-related mortality, which has significant implications in HHWSs. PMID:22673187

  3. Comparative Exposure Assessment of ESBL-Producing Escherichia coli through Meat Consumption

    PubMed Central

    Pielaat, Annemarie; Smid, Joost H.; van Duijkeren, Engeline; Vennemann, Francy B. C.; Wijnands, Lucas M.; Chardon, Jurgen E.

    2017-01-01

    The presence of extended-spectrum β-lactamase (ESBL) and plasmidic AmpC (pAmpC) producing Escherichia coli (EEC) in food animals, especially broilers, has become a major public health concern. The aim of the present study was to quantify the EEC exposure of humans in The Netherlands through the consumption of meat from different food animals. Calculations were done with a simplified Quantitative Microbiological Risk Assessment (QMRA) model. The model took the effect of pre-retail processing, storage at the consumers home and preparation in the kitchen (cross-contamination and heating) on EEC numbers on/in the raw meat products into account. The contribution of beef products (78%) to the total EEC exposure of the Dutch population through the consumption of meat was much higher than for chicken (18%), pork (4.5%), veal (0.1%) and lamb (0%). After slaughter, chicken meat accounted for 97% of total EEC load on meat, but chicken meat experienced a relatively large effect of heating during food preparation. Exposure via consumption of filet americain (a minced beef product consumed raw) was predicted to be highest (61% of total EEC exposure), followed by chicken fillet (13%). It was estimated that only 18% of EEC exposure occurred via cross-contamination during preparation in the kitchen, which was the only route by which EEC survived for surface-contaminated products. Sensitivity analysis showed that model output is not sensitive for most parameters. However, EEC concentration on meat other than chicken meat was an important data gap. In conclusion, the model assessed that consumption of beef products led to a higher exposure to EEC than chicken products, although the prevalence of EEC on raw chicken meat was much higher than on beef. The (relative) risk of this exposure for public health is yet unknown given the lack of a modelling framework and of exposure studies for other potential transmission routes. PMID:28056081

  4. Reaching new heights: Comparing interpretation bias modification to exposure therapy for extreme height fear

    PubMed Central

    Steinman, Shari A.; Teachman, Bethany A.

    2014-01-01

    Objective Cognitive models of anxiety disorders posit that biases in interpretation maintain, and potentially cause, anxiety. This study tested whether it is possible to decrease height fear symptoms through cognitive bias modification for interpretations (CBM-I). Additionally, the clinical utility of CBM-I was tested by comparing it to an already established treatment: exposure therapy. Method Extremely height fearful (N = 110) individuals participated in the study. Acrophobic symptoms were measured before and after two sessions of CBM-I, and compared to the standard treatment for acrophobia (exposure therapy), a combination of CBM-I and exposure therapy, and a Control condition. Results In line with hypotheses, participants in the three active conditions showed greater response to treatment than the Control condition in height-relevant interpretation bias, symptoms, and behavioral avoidance on a height stressor, with few differences between the active conditions. Further, symptom change was mediated by change in interpretation bias. Conclusions Overall, findings suggest that different pathways to fear reduction (exposure vs. shifting interpretations) can lead to similar reductions in height fear. This study provides the first evidence that directly shifting cognitive processing, even with no therapist involvement, can reduce symptoms as effectively as the gold standard, therapist-directed exposure therapy. PMID:24588406

  5. Comparative occupational exposures to formaldehyde released from inhaled wood product dusts versus that in vapor form.

    PubMed

    Gosselin, Nathalie H; Brunet, Robert C; Carrier, Gaétan

    2003-05-01

    Particle boards and other wood boards are usually made with formaldehyde-based resins. Woodworkers are thus exposed to formaldehyde in vapor form as well as from airborne dust once it enters their respiratory tract. These workers remain exposed to formaldehyde released from the dust still present in their upper respiratory tract, even after their work shift. In assessing the risk associated with formaldehyde exposure, one needs to consider the relative importance of these two sources of exposure. This study proposes two kinetic models to estimate and compare the exposures. For various exposure scenarios, one model predicts the amount of formaldehyde absorbed from the ambient vapor form and the other predicts the amount absorbed by the respiratory tract upon its release from wood product dust. Model parameters are determined using data from published studies. Based on a daily work shift of 8 hr, with a dust concentration in air of 5 mg/m(3) and a formaldehyde concentration bound to dust of 9 microg/mg, model simulations predict that the amount of absorbed formaldehyde released from wood dust is approximately 1/100 of the amount absorbed from the ambient vapor form at a concentration level of 0.38 mg/m(3) (0.3 ppm). Since the formaldehyde concentration in wood dust used above is much higher than usually observed while the dust and vapor form formaldehyde concentrations are of the order of acceptable upper values, these results indicate that the formaldehyde exposure from wood dust is comparatively negligible.

  6. Comparing population exposure to multiple Washington earthquake scenarios for prioritizing loss estimation studies

    USGS Publications Warehouse

    Wood, Nathan J.; Ratliff, Jamie L.; Schelling, John; Weaver, Craig S.

    2014-01-01

    Scenario-based, loss-estimation studies are useful for gauging potential societal impacts from earthquakes but can be challenging to undertake in areas with multiple scenarios and jurisdictions. We present a geospatial approach using various population data for comparing earthquake scenarios and jurisdictions to help emergency managers prioritize where to focus limited resources on data development and loss-estimation studies. Using 20 earthquake scenarios developed for the State of Washington (USA), we demonstrate how a population-exposure analysis across multiple jurisdictions based on Modified Mercalli Intensity (MMI) classes helps emergency managers understand and communicate where potential loss of life may be concentrated and where impacts may be more related to quality of life. Results indicate that certain well-known scenarios may directly impact the greatest number of people, whereas other, potentially lesser-known, scenarios impact fewer people but consequences could be more severe. The use of economic data to profile each jurisdiction’s workforce in earthquake hazard zones also provides additional insight on at-risk populations. This approach can serve as a first step in understanding societal impacts of earthquakes and helping practitioners to efficiently use their limited risk-reduction resources.

  7. Exposure-response analysis of risk of respiratory disease associated with occupational exposure to chrysotile asbestos.

    PubMed Central

    Stayner, L; Smith, R; Bailer, J; Gilbert, S; Steenland, K; Dement, J; Brown, D; Lemen, R

    1997-01-01

    OBJECTIVES: To evaluate alternative models and estimate risk of mortality from lung cancer and asbestosis after occupational exposure to chrysotile asbestos. METHODS: Data were used from a recent update of a cohort mortality study of workers in a South Carolina textile factory. Alternative exposure-response models were evaluated with Poisson regression. A model designed to evaluate evidence of a threshold response was also fitted. Lifetime risks of lung cancer and asbestosis were estimated with an actuarial approach that accounts for competing causes of death. RESULTS: A highly significant exposure-response relation was found for both lung cancer and asbestosis. The exposure-response relation for lung cancer seemed to be linear on a multiplicative scale, which is consistent with previous analyses of lung cancer and exposure to asbestos. In contrast, the exposure-response relation for asbestosis seemed to be nonlinear on a multiplicative scale in this analysis. There was no significant evidence for a threshold in models of either the lung cancer or asbestosis. The excess lifetime risk for white men exposed for 45 years at the recently revised OSHA standard of 0.1 fibre/ml was predicted to be about 5/1000 for lung cancer, and 2/1000 for asbestosis. CONCLUSIONS: This study confirms the findings from previous investigations of a strong exposure-response relation between exposure to chrysotile asbestos and mortality from lung cancer, and asbestosis. The risk estimates for lung cancer derived from this analysis are higher than those derived from other populations exposed to chrysotile asbestos. Possible reasons for this discrepancy are discussed. PMID:9423577

  8. Estimate of safe human exposure levels for lunar dust based on comparative benchmark dose modeling.

    PubMed

    James, John T; Lam, Chiu-Wing; Santana, Patricia A; Scully, Robert R

    2013-04-01

    Brief exposures of Apollo astronauts to lunar dust occasionally elicited upper respiratory irritation; however, no limits were ever set for prolonged exposure to lunar dust. The United States and other space faring nations intend to return to the moon for extensive exploration within a few decades. In the meantime, habitats for that exploration, whether mobile or fixed, must be designed to limit human exposure to lunar dust to safe levels. Herein we estimate safe exposure limits for lunar dust collected during the Apollo 14 mission. We instilled three respirable-sized (∼2 μ mass median diameter) lunar dusts (two ground and one unground) and two standard dusts of widely different toxicities (quartz and TiO₂) into the respiratory system of rats. Rats in groups of six were given 0, 1, 2.5 or 7.5 mg of the test dust in a saline-Survanta® vehicle, and biochemical and cellular biomarkers of toxicity in lung lavage fluid were assayed 1 week and one month after instillation. By comparing the dose--response curves of sensitive biomarkers, we estimated safe exposure levels for astronauts and concluded that unground lunar dust and dust ground by two different methods were not toxicologically distinguishable. The safe exposure estimates were 1.3 ± 0.4 mg/m³ (jet-milled dust), 1.0 ± 0.5 mg/m³ (ball-milled dust) and 0.9 ± 0.3 mg/m³ (unground, natural dust). We estimate that 0.5-1 mg/m³ of lunar dust is safe for periodic human exposures during long stays in habitats on the lunar surface.

  9. [Exposure to pollutants and allergens in the asthmatic child compared with the healthy child].

    PubMed

    Sarrazola Sanjuan, D M; Salas Ramírez, M; Segura Méndez, N H; Medrano, S; Martínez Cairo Cueto, S

    1997-01-01

    To assess the frequency of exposure to allergens and indoor pollutants of school age asthmatic children at the time of their first visit to the specialist, we studied 14 cases with the diagnosis of asthma according to international criteria, and 21 healthy controls. The parents of the children filed a questionnaire asking about socio-economic level, family history of asthma, exposure to allergens or indoor pollutants, and clinical severity of the disease. Questionnaires with less than 80% of the responses were excluded from analysis. Asthmatic patients had higher frequency of exposure to tobacco smoke (42.8% vs 38%), moisture in the home walls (42.9% vs 19%), and to dust reservoirs (71.4% vs 52.4%). A high proportion of the asthmatic patients did not apply adequate environmental control measures. Education for the patients and their primary care physicians must be increased, to reduce the morbidity of the diseases.

  10. Network Analysis in Comparative Social Sciences

    ERIC Educational Resources Information Center

    Vera, Eugenia Roldan; Schupp, Thomas

    2006-01-01

    This essay describes the pertinence of Social Network Analysis (SNA) for the social sciences in general, and discusses its methodological and conceptual implications for comparative research in particular. The authors first present a basic summary of the theoretical and methodological assumptions of SNA, followed by a succinct overview of its…

  11. Teacher Policy: A Framework for Comparative Analysis

    ERIC Educational Resources Information Center

    Tatto, Maria Teresa

    2008-01-01

    This article outlines a framework for analysis of teacher focused policy studies within an international and comparative perspective. Using the notion of the professional life cycle of teachers, the article examines examples of key empirical studies that illustrate the impact of policy on addressing such issues as teacher recruitment, education,…

  12. Comparative genomic analysis of esophageal cancers.

    PubMed

    Caygill, Christine P J; Gatenby, Piers A C; Herceg, Zdenko; Lima, Sheila C S; Pinto, Luis F R; Watson, Anthony; Wu, Ming-Shiang

    2014-09-01

    The following, from the 12th OESO World Conference: Cancers of the Esophagus, includes commentaries on comparative genomic analysis of esophageal cancers: genomic polymorphisms, the genetic and epigenetic drivers in esophageal cancers, and the collection of data in the UK Barrett's Oesophagus Registry.

  13. Asbestos exposure and gastrointestinal malignancy review and meta-analysis

    SciTech Connect

    Frumkin, H.; Berlin, J.

    1988-01-01

    The epidemiologic literature linking asbestos exposure with gastrointestinal malignancy is reviewed. Problems in comparing studies are discussed, appropriate strategies for comparison are developed, and study results are pooled using a model which accounts for both intrastudy and interstudy variability. Stratification of cohorts by dose reveals that significant asbestos exposure, as indicated by a lung cancer standardized mortality ratio (SMR) of at least 200, is associated with an elevated gastrointestinal cancer SMR for five or six end points examined.

  14. Assessing variability and comparing short-term biomarkers of styrene exposure using a repeated measurements approach.

    PubMed

    Fustinoni, S; Manini, P; Campo, L; De Palma, G; Andreoli, R; Mutti, A; Bertazzi, P A; Rappaport, S M

    2010-01-15

    The aim of this work is to compare several short-term biomarkers of styrene exposure, namely urinary styrene (StyU), mercapturic acids (M1+M2), mandelic acid (MA), phenylglyoxylic acid (PGA), phenylglycine (PHG), and 4-vinylphenol conjugates (VP), for use as biomarkers of exposure in epidemiologic studies. A repeated measurements protocol (typically 4 measurements per worker over 6 weeks) was applied to measure airborne styrene (StyA) and urinary biomarkers in 10 varnish and 8 fiberglass reinforced plastic workers. Estimated geometric mean personal exposures to StyA were 2.96mg/m(3) in varnish workers and 15.7mg/m(3) in plastic workers. The corresponding levels of StyU, M1+M2, MA, PGA, MA+PGA, PHG and VP were 5.13microg/L, 0.111, 38.2, 22.7, 62.6, 0.978, and 3.97mg/g creatinine in varnish workers and 8.38microg/L, 0.303, 146, 83.4, 232, 2.85 and 3.97mg/g creatinine in plastic workers. Within-worker (sigma(wY)(2)) and between-worker (sigma(bY)(2)) variance components were estimated from the log-transformed data as were the corresponding fold ranges containing 95% of the respective lognormal distributions of daily levels ((w)R(0.95)) and subject-specific mean levels ((b)R(0.95)). Estimates of (w)R(0.95) (range: 4-26) were generally smaller than those of (b)R(0.95) (range: 5-790) for both environmental and biological markers; this indicates that exposures varied much more between workers than within workers in these groups. Since attenuation bias in an estimated exposure-response relationship increases with the variance ratio lambda=sigma(wY)(2)/sigma(bY)(2), we estimated values of lambda for all exposure measures in our study. Values of lambda were typically much less than one (median=0.220) and ranged from 0.089 for M1+M2 in plastic workers to 1.38 for PHG in varnish workers. Since values of lambda were 0.147 and 0.271 for StyA in varnish workers and plastic workers, respectively, compared to 0.178 and 0.210 for MA in the same groups, our results suggest that either

  15. Comparative assessment of three in vitro exposure methods for combustion toxicity.

    PubMed

    Lestari, Fatma; Markovic, Boban; Green, Anthony R; Chattopadhyay, Gautam; Hayes, Amanda J

    2006-01-01

    A comparative assessment of three approaches for the use of human cells in vitro to investigate combustion toxicity was conducted. These included one indirect and two direct (passive and dynamic) exposure methods. The indirect method used an impinger system in which culture medium was used to trap the toxicants, whilst the direct exposure involved the use of a Horizontal Harvard Navicyte Chamber at the air/liquid interface. The cytotoxic effects of thermal decomposition products were assessed using the MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay (Promega) on a selection of human cells including: HepG2, A549 and skin fibroblasts. A small scale laboratory fire test using a vertical tube furnace was designed for the generation of combustion products. Polymethyl methacrylate (PMMA) was selected as a model polymer to study the cytotoxic effects of combustion products. NOAEC (no observable adverse effect concentration), IC10 (10% inhibitory concentration), IC50 (50% inhibitory concentration) and TLC (total lethal concentration) values were determined from dose response curves. Assessment using the NRU (neutral red uptake) and ATP (adenosine triphosphate) assays on human lung derived cells (A549) was also undertaken. Comparison between in vitro cytotoxicity results against published toxicity data for PMMA combustion and predicted LC50 (50% lethal concentration) values calculated from identified compounds using GCMS (gas chromatography mass spectrometry) was determined. The results suggested that the indirect exposure method did not appear to simulate closely exposure via inhalation, whilst exposure at the air/liquid interface by using the dynamic method proved to be a more representative method of human inhalation. This exposure method may be a potential system for in vitro cytotoxicity testing in combustion toxicity.

  16. A comparative pharmacokinetic estimate of mercury in U.S. Infants following yearly exposures to inactivated influenza vaccines containing thimerosal.

    PubMed

    Mitkus, Robert J; King, David B; Walderhaug, Mark O; Forshee, Richard A

    2014-04-01

    The use of thimerosal preservative in childhood vaccines has been largely eliminated over the past decade in the United States because vaccines have been reformulated in single-dose vials that do not require preservative. An exception is the inactivated influenza vaccines, which are formulated in both multidose vials requiring preservative and preservative-free single-dose vials. As part of an ongoing evaluation by USFDA of the safety of biologics throughout their lifecycle, the infant body burden of mercury following scheduled exposures to thimerosal preservative in inactivated influenza vaccines in the United States was estimated and compared to the infant body burden of mercury following daily exposures to dietary methylmercury at the reference dose established by the USEPA. Body burdens were estimated using kinetic parameters derived from experiments conducted in infant monkeys that were exposed episodically to thimerosal or MeHg at identical doses. We found that the body burden of mercury (AUC) in infants (including low birth weight) over the first 4.5 years of life following yearly exposures to thimerosal was two orders of magnitude lower than that estimated for exposures to the lowest regulatory threshold for MeHg over the same time period. In addition, peak body burdens of mercury following episodic exposures to thimerosal in this worst-case analysis did not exceed the corresponding safe body burden of mercury from methylmercury at any time, even for low-birth-weight infants. Our pharmacokinetic analysis supports the acknowledged safety of thimerosal when used as a preservative at current levels in certain multidose infant vaccines in the United States.

  17. Loss Exposure and Risk Analysis Methodology (LERAM) Project Database Design.

    DTIC Science & Technology

    1996-06-01

    MISREPS) to more capably support system safety engineering concepts such as hazard analysis and risk management. As part of the Loss Exposure and Risk ... Analysis Methodology (LERAM) project, the research into the methods which we employ to report, track, and analyze hazards has resulted in a series of low

  18. Comparative Benchmark Dose Modeling as a Tool to Make the First Estimate of Safe Human Exposure Levels to Lunar Dust

    NASA Technical Reports Server (NTRS)

    James, John T.; Lam, Chiu-wing; Scully, Robert R.

    2013-01-01

    Brief exposures of Apollo Astronauts to lunar dust occasionally elicited upper respiratory irritation; however, no limits were ever set for prolonged exposure ot lunar dust. Habitats for exploration, whether mobile of fixed must be designed to limit human exposure to lunar dust to safe levels. We have used a new technique we call Comparative Benchmark Dose Modeling to estimate safe exposure limits for lunar dust collected during the Apollo 14 mission.

  19. National Launch System comparative economic analysis

    NASA Technical Reports Server (NTRS)

    Prince, A.

    1992-01-01

    Results are presented from an analysis of economic benefits (or losses), in the form of the life cycle cost savings, resulting from the development of the National Launch System (NLS) family of launch vehicles. The analysis was carried out by comparing various NLS-based architectures with the current Shuttle/Titan IV fleet. The basic methodology behind this NLS analysis was to develop a set of annual payload requirements for the Space Station Freedom and LEO, to design launch vehicle architectures around these requirements, and to perform life-cycle cost analyses on all of the architectures. A SEI requirement was included. Launch failure costs were estimated and combined with the relative reliability assumptions to measure the effects of losses. Based on the analysis, a Shuttle/NLS architecture evolving into a pressurized-logistics-carrier/NLS architecture appears to offer the best long-term cost benefit.

  20. NORMAL MAMMARY GLAND MORPHOLOGY IN PUBERTAL FEMALE MICE FOLLOWING IN UTERO AND LACTATIONAL EXPOSURE TO GENISTEIN AT LEVELS COMPARABLE TO HUMAN DIETARY EXPOSURE. (R827402)

    EPA Science Inventory

    The objective of the study was to determine the effect of in utero and lactational exposure to genistein (0, 0.1, 0.5, 2.5 and 10 mg/kg/day) on mammary gland morphology in female B6D2F1 mice at levels comparable to or greater than human exposures. The effect of diethylstilbest...

  1. Comparative analysis of twelve Dothideomycete plant pathogens

    SciTech Connect

    Ohm, Robin; Aerts, Andrea; Salamov, Asaf; Goodwin, Stephen B.; Grigoriev, Igor

    2011-03-11

    The Dothideomycetes are one of the largest and most diverse groups of fungi. Many are plant pathogens and pose a serious threat to agricultural crops grown for biofuel, food or feed. Most Dothideomycetes have only a single host and related Dothideomycete species can have very diverse host plants. Twelve Dothideomycete genomes have currently been sequenced by the Joint Genome Institute and other sequencing centers. They can be accessed via Mycocosm which has tools for comparative analysis

  2. Embedded Hyperchaotic Generators: A Comparative Analysis

    NASA Astrophysics Data System (ADS)

    Sadoudi, Said; Tanougast, Camel; Azzaz, Mohamad Salah; Dandache, Abbas

    In this paper, we present a comparative analysis of FPGA implementation performances, in terms of throughput and resources cost, of five well known autonomous continuous hyperchaotic systems. The goal of this analysis is to identify the embedded hyperchaotic generator which leads to designs with small logic area cost, satisfactory throughput rates, low power consumption and low latency required for embedded applications such as secure digital communications between embedded systems. To implement the four-dimensional (4D) chaotic systems, we use a new structural hardware architecture based on direct VHDL description of the forth order Runge-Kutta method (RK-4). The comparative analysis shows that the hyperchaotic Lorenz generator provides attractive performances compared to that of others. In fact, its hardware implementation requires only 2067 CLB-slices, 36 multipliers and no block RAMs, and achieves a throughput rate of 101.6 Mbps, at the output of the FPGA circuit, at a clock frequency of 25.315 MHz with a low latency time of 316 ns. Consequently, these good implementation performances offer to the embedded hyperchaotic Lorenz generator the advantage of being the best candidate for embedded communications applications.

  3. Statistical analysis of a dynamic model for dietary contaminant exposure.

    PubMed

    Bertail, P; Clémençon, S; Tressou, J

    2010-03-01

    This paper is devoted to the statistical analysis of a stochastic model introduced in [P. Bertail, S. Clémençon, and J. Tressou, A storage model with random release rate for modelling exposure to food contaminants, Math. Biosci. Eng. 35 (1) (2008), pp. 35-60] for describing the phenomenon of exposure to a certain food contaminant. In this modelling, the temporal evolution of the contamination exposure is entirely determined by the accumulation phenomenon due to successive dietary intakes and the pharmacokinetics governing the elimination process inbetween intakes, in such a way that the exposure dynamic through time is described as a piecewise deterministic Markov process. Paths of the contamination exposure process are scarcely observable in practice, therefore intensive computer simulation methods are crucial for estimating the time-dependent or steady-state features of the process. Here we consider simulation estimators based on consumption and contamination data and investigate how to construct accurate bootstrap confidence intervals (CI) for certain quantities of considerable importance from the epidemiology viewpoint. Special attention is also paid to the problem of computing the probability of certain rare events related to the exposure process path arising in dietary risk analysis using multilevel splitting or importance sampling (IS) techniques. Applications of these statistical methods to a collection of data sets related to dietary methyl mercury contamination are discussed thoroughly.

  4. A Randomized, Controlled Trial of Meditation Compared to Exposure Therapy and Education Control on PTSD in Veterans

    DTIC Science & Technology

    2014-10-01

    Award Number: W81XWH-12-1-0576 TITLE: A Randomized, Controlled Trial of Meditation Compared to Exposure Therapy and...COVERED 30 Sep 2013 - 29 Sep 2014 4. TITLE AND SUBTITLE A Randomized, Controlled Trial of Meditation Compared to Exposure Therapy and Education... Meditation (TM) vs. Prolonged Exposure (PE) and PTSD health education control (EC), using the Clinician Administered PTSD Scale (CAPS) (primary

  5. A Randomized, Controlled Trial of Meditation Compared to Exposure Therapy and Education Control on PTSD in Veterans

    DTIC Science & Technology

    2013-10-01

    AD_________________ Award Number: W81XWH-12-1-0576 TITLE: A Randomized, Controlled Trial of Meditation Compared to Exposure...SUBTITLE A Randomized, Controlled Trial of Meditation Compared to Exposure Therapy and Education Control on PTSD in Veterans 5a. CONTRACT NUMBER...will: 1) evaluate effects of Transcendental Meditation (TM) vs. Prolonged Exposure (PE) and PTSD health education control (EC), using the Clinician

  6. Arsenic exposure in US public and domestic drinking water supplies: a comparative risk assessment.

    PubMed

    Kumar, Arun; Adak, Probas; Gurian, Patrick L; Lockwood, John R

    2010-05-01

    Although approximately 35 million people in the US obtain drinking water from domestic wells, few studies have investigated the risk of arsenic exposure from this source. In this paper arsenic concentrations were modeled for public and domestic wells using a dataset from the US Geological Survey (USGS). Excess lifetime and annual risks for lung and bladder cancer were calculated based on the carcinogenic potency and average arsenic concentrations in public and domestic water supplies. Monte Carlo uncertainty analysis was used to estimate the degree of confidence in these estimations. Results indicated that domestic well users accounted for 12% of the US population, but 23% of overall arsenic exposure from drinking water. Assuming that the new and more restrictive arsenic maximum contaminant limit (MCL) is implemented for public water supplies, it is anticipated that the proportion of people experiencing excess annual fatalities from drinking water from domestic wells will increase to 29% unless corresponding efforts are made to reduce exposures among domestic well users. Differences between public and domestic wells were not consistent across the nation. Public wells tend to tap deeper aquifers than domestic wells, and as a result local arsenic-depth trends can contribute to differences between public and domestic wells. Domestic wells and public wells in the western US have the highest arsenic levels with excess fatality risks estimated to be in the range of 1 per 9300 to 1 per 6600 in these regions. Uncertainty distributions of excess fatalities were developed and resultant uncertainties were propagated in arsenic exposure and potency factor. Uncertainty in the carcinogenic potency of arsenic was the dominant source of uncertainty in most regions, but for domestic wells in the New England and Southeast regions uncertainty in arsenic exposure was dominant, indicating that additional data on arsenic concentrations in these areas would substantially improve regional

  7. Distributions of personal VOC exposures: a population-based analysis.

    PubMed

    Jia, Chunrong; D'Souza, Jennifer; Batterman, Stuart

    2008-10-01

    Information regarding the distribution of volatile organic compound (VOC) concentrations and exposures is scarce, and there have been few, if any, studies using population-based samples from which representative estimates can be derived. This study characterizes distributions of personal exposures to ten different VOCs in the U.S. measured in the 1999--2000 National Health and Nutrition Examination Survey (NHANES). Personal VOC exposures were collected for 669 individuals over 2-3 days, and measurements were weighted to derive national-level statistics. Four common exposure sources were identified using factor analyses: gasoline vapor and vehicle exhaust, methyl tert-butyl ether (MBTE) as a gasoline additive, tap water disinfection products, and household cleaning products. Benzene, toluene, ethyl benzene, xylenes chloroform, and tetrachloroethene were fit to log-normal distributions with reasonably good agreement to observations. 1,4-Dichlorobenzene and trichloroethene were fit to Pareto distributions, and MTBE to Weibull distribution, but agreement was poor. However, distributions that attempt to match all of the VOC exposure data can lead to incorrect conclusions regarding the level and frequency of the higher exposures. Maximum Gumbel distributions gave generally good fits to extrema, however, they could not fully represent the highest exposures of the NHANES measurements. The analysis suggests that complete models for the distribution of VOC exposures require an approach that combines standard and extreme value distributions, and that carefully identifies outliers. This is the first study to provide national-level and representative statistics regarding the VOC exposures, and its results have important implications for risk assessment and probabilistic analyses.

  8. Comparative Genome Analysis of Enterobacter cloacae

    PubMed Central

    Liu, Wing-Yee; Wong, Chi-Fat; Chung, Karl Ming-Kar; Jiang, Jing-Wei; Leung, Frederick Chi-Ching

    2013-01-01

    The Enterobacter cloacae species includes an extremely diverse group of bacteria that are associated with plants, soil and humans. Publication of the complete genome sequence of the plant growth-promoting endophytic E. cloacae subsp. cloacae ENHKU01 provided an opportunity to perform the first comparative genome analysis between strains of this dynamic species. Examination of the pan-genome of E. cloacae showed that the conserved core genome retains the general physiological and survival genes of the species, while genomic factors in plasmids and variable regions determine the virulence of the human pathogenic E. cloacae strain; additionally, the diversity of fimbriae contributes to variation in colonization and host determination of different E. cloacae strains. Comparative genome analysis further illustrated that E. cloacae strains possess multiple mechanisms for antagonistic action against other microorganisms, which involve the production of siderophores and various antimicrobial compounds, such as bacteriocins, chitinases and antibiotic resistance proteins. The presence of Type VI secretion systems is expected to provide further fitness advantages for E. cloacae in microbial competition, thus allowing it to survive in different environments. Competition assays were performed to support our observations in genomic analysis, where E. cloacae subsp. cloacae ENHKU01 demonstrated antagonistic activities against a wide range of plant pathogenic fungal and bacterial species. PMID:24069314

  9. Comparative chlorpyrifos pharmacokinetics via multiple routes of exposure and vehicles of administration in the adult rat.

    PubMed

    Smith, Jordan Ned; Campbell, James A; Busby-Hjerpe, Andrea L; Lee, Sookwang; Poet, Torka S; Barr, Dana B; Timchalk, Charles

    2009-06-30

    Chlorpyrifos (CPF) is a commonly used organophosphorus pesticide. A number of toxicity and mechanistic studies have been conducted in animals, where CPF has been administered via a variety of different exposure routes and dosing vehicles. This study compared chlorpyrifos (CPF) pharmacokinetics using oral, intravenous (IV), and subcutaneous (SC) exposure routes and corn oil, saline/Tween 20, and dimethyl sulfoxide (DMSO) as dosing vehicles. Two groups of rats were co-administered target doses (5 mg/kg) of CPF and isotopically labeled CPF (L-CPF). One group was exposed by both oral (CPF) and IV (L-CPF) routes using saline/Tween 20 vehicle; whereas, the second group was exposed by the SC route using two vehicles, corn oil (CPF) and DMSO (L-CPF). A third group was only administered CPF by the oral route in corn oil. For all treatments, blood and urine time course samples were collected and analyzed for 3,5,6-trichloro-2-pyridinol (TCPy), and isotopically labeled 3,5,6-trichloro-2-pyridinol (L-TCPy). Peak TCPy/L-TCPy concentrations in blood (20.2 micromol/l), TCPy/L-TCPy blood AUC (94.9 micromol/lh), and percent of dose excreted in urine (100%) were all highest in rats dosed orally with CPF in saline/Tween 20 and second highest in rats dosed orally with CPF in corn oil. Peak TCPy concentrations in blood were more rapidly obtained after oral administration of CPF in saline/Tween 20 compared to all other dosing scenarios (>1.5 h). These results indicate that orally administered CPF is more extensively metabolized than systemic exposures of CPF (SC and IV), and vehicle of administration also has an effect on absorption rates. Thus, equivalent doses via different routes and/or vehicles of administration could potentially lead to different body burdens of CPF, different rates of bioactivation to CPF-oxon, and different toxic responses. Simulations using a physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) model for CPF are consistent with these possibilities

  10. A Randomized, Controlled Trial of Meditation Compared to Exposure Therapy and Education Control on PTSD in Veterans

    DTIC Science & Technology

    2013-08-01

    Meditation Compared to Exposure Therapy and Education Control on PTSD in Veterans PRINCIPAL INVESTIGATOR: Thomas Rutledge, Ph.D...Controlled Trial of Meditation Compared to Exposure 5a. CONTRACT NUMBER Therapy and Education Control on PTSD in Veterans 5b. GRANT NUMBER W81XWH-12-1...SUPPLEMENTARY NOTES 14. ABSTRACT This study consists of a comparative effectiveness trial of Transcendental Meditation (TM) compared to

  11. Childhood exposure to DEHP, DBP and BBP under existing chemical management systems: a comparative study of sources of childhood exposure in Korea and in Denmark.

    PubMed

    Lee, Jihyun; Lee, Jong-Hyeon; Kim, Chan-Kook; Thomsen, Marianne

    2014-02-01

    In this paper, the cumulative risks of Di(2-ethylhexyl) phthalate (DEHP), Di-n-butyl phthalate (DBP), and Benzyl-butyl phthalate (BBP) to 2-year-old children in two countries: one European (Denmark) and one Asian (South Korea) were compared. Denmark does not produce phthalates as a raw material, while Korea produces more than 0.4milliontons of the three above-mentioned phthalates each year. First, a comparative review of the existing phthalate regulations in the two countries was performed. Next, the level of childhood phthalate exposure from environmental and food sources was estimated using an exposure scenario approach. Then, the scenario based exposure level was compared with back-calculated exposure levels based on biomonitored urinary phthalate metabolite concentrations. The result verifies the existence of varying territorial human background exposure levels and the gap between exposure estimations based on exposure modeling and biomonitoring data. Cumulative childhood risk levels in Denmark were lower than in Korea. For both countries, risk levels from back calculation were higher than those from scenario estimation. The median cumulative risk levels from scenario estimation and back calculation respectively were 0.24 and up to 0.5 in Denmark while 0.52 and up to 0.95 in Korea. Food and indoor dust were the main exposure sources for all three phthalates. In order to protect human health from cumulative risks of these phthalates, the exposure scenarios in existing regulations such as the EU REACH need to be strengthened. Moreover, based on the contributions from different exposure sources, national specific risk management tools need to be developed and strengthened, applying a systemic approach to promote sustainable material flows.

  12. Inpatient care in Kazakhstan: A comparative analysis

    PubMed Central

    Kumar, Ainur B.; Izekenova, Aigulsum; Abikulova, Akmaral

    2013-01-01

    Background: Reforms in inpatient care are critical for the enhancement of the efficiency of health systems. It still remains the main costly sector of the health system, accounting for more than 60% of all expenditures. Inappropriate and ineffective use of the hospital infrastructure is also a big issue. We aimed to analyze statistical data on health indices and dynamics of the hospital stock in Kazakhstan in comparison with those of developed countries. Materials and Methods: Study design is comparative quantitative analysis of inpatient care indicators. We used information and analytical methods, content analysis, mathematical treatment, and comparative analysis of statistical data on health system and dynamics of hospital stock in Kazakhstan and some other countries of the world [Organization for Economic Cooperation and Development (OECD), USA, Canada, Russia, China, Japan, and Korea] over the period 2001-2011. Results: Despite substantial and continuous reductions over the past 10 years, hospitalization rates in Kazakhstan still remain high compared to some developed countries, including those of the OECD. In fact, the hospital stay length for all patients in Kazakhstan in 2011 is around 9.9 days, hospitalization ratio per 100 people is 16.3, and hospital beds capacity is 100 per 10,000 inhabitants. Conclusion: The decreased level of beds may adversely affect both medical organization and health system operations. Alternatives to the existing inpatient care are now being explored. The introduction of the unified national healthcare system allows shifting the primary focus on primary care organizations, which can decrease the demand on inpatient care as a result of improving the health status of people at the primary care level. PMID:24516484

  13. Stock index dynamics worldwide: a comparative analysis

    NASA Astrophysics Data System (ADS)

    Cortines, A. A. G.; Anteneodo, C.; Riera, R.

    2008-09-01

    We perform a comparative analysis of twenty-four daily stock indices across the world, encompassing developed and emerging markets. We compute, directly from the return empirical time series, the Kramers-Moyal (KM) expansion coefficients that govern the evolution of the probability density function of returns throughout timelags. Our study discloses universal patterns of the KM coefficients, which can be described in terms of a few microscopic parameters. These parameters allow to quantify features such as deviations from Gaussianity or from efficiency, providing a tool to discriminate market dynamics.

  14. Fundus camera systems: a comparative analysis.

    PubMed

    DeHoog, Edward; Schwiegerling, James

    2009-01-10

    Retinal photography requires the use of a complex optical system, called a fundus camera, capable of illuminating and imaging the retina simultaneously. The patent literature shows two design forms but does not provide the specifics necessary for a thorough analysis of the designs to be performed. We have constructed our own designs based on the patent literature in optical design software and compared them for illumination efficiency, image quality, ability to accommodate for patient refractive error, and manufacturing tolerances, a comparison lacking in the existing literature.

  15. Fundus camera systems: a comparative analysis

    PubMed Central

    DeHoog, Edward; Schwiegerling, James

    2010-01-01

    Retinal photography requires the use of a complex optical system, called a fundus camera, capable of illuminating and imaging the retina simultaneously. The patent literature shows two design forms but does not provide the specifics necessary for a thorough analysis of the designs to be performed. We have constructed our own designs based on the patent literature in optical design software and compared them for illumination efficiency, image quality, ability to accommodate for patient refractive error, and manufacturing tolerances, a comparison lacking in the existing literature. PMID:19137032

  16. RECENT DEVELOPMENTS IN EXHALED BREATH ANALYSIS AND HUMAN EXPOSURE RESEARCH

    EPA Science Inventory

    Exhaled breath collection and analysis has historically been used in environmental research studies to characterize exposures to volatile organic compounds. The use of this approach is based on the fact that many compounds present in blood are reflected in the breath, and that u...

  17. Wastewater exposure and health—a comparative study of two occupational groups

    PubMed Central

    Hansen, E; Hilden, J; Klausen, H; Rosdahl, N

    2003-01-01

    Aims: To investigate whether wastewater workers are at increased risk of developing cancer. Methods: Two cohorts of workers employed by the City of Copenhagen, 591 wastewater workers and 1545 water supply workers (controls), were followed from 1965 until 1998. These two cohorts were compared in terms of cause specific mortality and cancer incidence. Results: The wastewater workers' mortality exceeded that of the controls (relative risk (RR) = 1.25, 95% CI: 1.03 to 1.51). A similar small excess was seen for cancer incidence (RR = 1.27, 95% CI: 0.97 to 1.67). Though rare, there was a strongly increased incidence of primary liver cancer among the wastewater workers (RR = 8.9, 95% CI: 1.5 to 51.5). Conclusion: The excess mortality seen among the wastewater workers was smaller than originally feared. It may partly have been due to their occupational exposure, and for preventive purposes, exposure to wastewater and sludge should be minimised. The possibility that sewage exposure confers an increased risk of primary liver cancer deserves further investigation. PMID:12883021

  18. Measuring exposure in Hurricane Katrina: a meta-analysis and an integrative data analysis.

    PubMed

    Chan, Christian S; Rhodes, Jean E

    2014-01-01

    To date there is no consensus on the operationalization of exposure severity in the study of the impact of natural disasters. This is problematic because incomplete and inconsistent measurement of exposure limits the internal and external validity of disaster studies. The current paper examined the predictive validity of severity measures in two interrelated studies of Hurricane Katrina survivors. First, in a meta-analysis of eight studies that measured both exposure severity and posttraumatic stress, the effect size was estimated to be r = .266. The moderating effects of sample and study characteristics were examined and we found that minority status and number of stressors assessed were significant moderators. Second, in an integrative data analysis of five independent samples of Hurricane Katrina survivors, the impact of specific disaster-related stressors on mental health was compared. Threat to physical integrity of self and others were found to have the strongest association with posttraumatic stress (PTS) and general psychological distress (GPD). The lack of basic necessities, such as food, water, and medical care, and loss of pet were also found to be strongly associated with both PTS and GPD. The results from the two studies are integrated and their implication for disaster research and relief are discussed.

  19. Measuring Exposure in Hurricane Katrina: A Meta-Analysis and an Integrative Data Analysis

    PubMed Central

    Chan, Christian S.; Rhodes, Jean E.

    2014-01-01

    To date there is no consensus on the operationalization of exposure severity in the study of the impact of natural disasters. This is problematic because incomplete and inconsistent measurement of exposure limits the internal and external validity of disaster studies. The current paper examined the predictive validity of severity measures in two interrelated studies of Hurricane Katrina survivors. First, in a meta-analysis of eight studies that measured both exposure severity and posttraumatic stress, the effect size was estimated to be r = .266. The moderating effects of sample and study characteristics were examined and we found that minority status and number of stressors assessed were significant moderators. Second, in an integrative data analysis of five independent samples of Hurricane Katrina survivors, the impact of specific disaster-related stressors on mental health was compared. Threat to physical integrity of self and others were found to have the strongest association with posttraumatic stress (PTS) and general psychological distress (GPD). The lack of basic necessities, such as food, water, and medical care, and loss of pet were also found to be strongly associated with both PTS and GPD. The results from the two studies are integrated and their implication for disaster research and relief are discussed. PMID:24713851

  20. Comparative biology approaches for charged particle exposures and cancer development processes

    NASA Astrophysics Data System (ADS)

    Kronenberg, Amy; Gauny, Stacey; Kwoh, Ely; Sudo, Hiroko; Wiese, Claudia; Dan, Cristian; Turker, Mitchell

    Comparative biology studies can provide useful information for the extrapolation of results be-tween cells in culture and the more complex environment of the tissue. In other circumstances, they provide a method to guide the interpretation of results obtained for cells from differ-ent species. We have considered several key cancer development processes following charged particle exposures using comparative biology approaches. Our particular emphases have been mutagenesis and genomic instability. Carcinogenesis requires the accumulation of mutations and most of htese mutations occur on autosomes. Two loci provide the greatest avenue for the consideration of charged particle-induced mutation involving autosomes: the TK1 locus in human cells and the APRT locus in mouse cells. Each locus can provide information on a wide variety of mutational changes, from small intragenic mutations through multilocus dele-tions and extensive tracts of mitotic recombination. In addition, the mouse model can provide a direct measurement of chromosome loss which cannot be accomplished in the human cell system. Another feature of the mouse APRT model is the ability to examine effects for cells exposed in vitro with those obtained for cells exposed in situ. We will provide a comparison of the results obtained for the TK1 locus following 1 GeV/amu Fe ion exposures to the human lymphoid cells with those obtained for the APRT locus for mouse kidney epithelial cells (in vitro or in situ). Substantial conservation of mechanisms is found amongst these three exposure scenarios, with some differences attributable to the specific conditions of exposure. A similar approach will be applied to the consideraiton of proton-induced autosomal mutations in the three model systems. A comparison of the results obtained for Fe ions vs. protons in each case will highlight LET-specificc differences in response. Another cancer development process that is receiving considerable interest is genomic instability. We

  1. A discriminant analysis of neuropsychological effect of low lead exposure.

    PubMed

    Boey, K W; Jeyaratnam, J

    1988-05-01

    The purpose of this study is to determine the contribution of psychological tests in discriminating neuropsychological effects of low lead exposure. The sample consists of 49 workers occupationally exposed to lead and a control group of 36 non-exposed workers. Their performance on various neuropsychological measures was subject to a discriminant analysis using the SPSS DISCRIMINANT subprogramme. The results indicate that simple reaction time, Digit Symbol (WAIS) and Trail-Making Test (Part A) provide the best combination of tests for the detection of neurotoxic effect of low lead exposure.

  2. Comparative Transcriptome Analysis of Four Prymnesiophyte Algae

    PubMed Central

    Koid, Amy E.; Liu, Zhenfeng; Terrado, Ramon; Jones, Adriane C.; Caron, David A.; Heidelberg, Karla B.

    2014-01-01

    Genomic studies of bacteria, archaea and viruses have provided insights into the microbial world by unveiling potential functional capabilities and molecular pathways. However, the rate of discovery has been slower among microbial eukaryotes, whose genomes are larger and more complex. Transcriptomic approaches provide a cost-effective alternative for examining genetic potential and physiological responses of microbial eukaryotes to environmental stimuli. In this study, we generated and compared the transcriptomes of four globally-distributed, bloom-forming prymnesiophyte algae: Prymnesium parvum, Chrysochromulina brevifilum, Chrysochromulina ericina and Phaeocystis antarctica. Our results revealed that the four transcriptomes possess a set of core genes that are similar in number and shared across all four organisms. The functional classifications of these core genes using the euKaryotic Orthologous Genes (KOG) database were also similar among the four study organisms. More broadly, when the frequencies of different cellular and physiological functions were compared with other protists, the species clustered by both phylogeny and nutritional modes. Thus, these clustering patterns provide insight into genomic factors relating to both evolutionary relationships as well as trophic ecology. This paper provides a novel comparative analysis of the transcriptomes of ecologically important and closely related prymnesiophyte protists and advances an emerging field of study that uses transcriptomics to reveal ecology and function in protists. PMID:24926657

  3. Comparative genome analysis of Basidiomycete fungi

    SciTech Connect

    Riley, Robert; Salamov, Asaf; Henrissat, Bernard; Nagy, Laszlo; Brown, Daren; Held, Benjamin; Baker, Scott; Blanchette, Robert; Boussau, Bastien; Doty, Sharon L.; Fagnan, Kirsten; Floudas, Dimitris; Levasseur, Anthony; Manning, Gerard; Martin, Francis; Morin, Emmanuelle; Otillar, Robert; Pisabarro, Antonio; Walton, Jonathan; Wolfe, Ken; Hibbett, David; Grigoriev, Igor

    2013-08-07

    Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes symbionts, pathogens, and saprotrophs including the majority of wood decaying and ectomycorrhizal species. To better understand the genetic diversity of this phylum we compared the genomes of 35 basidiomycetes including 6 newly sequenced genomes. These genomes span extremes of genome size, gene number, and repeat content. Analysis of core genes reveals that some 48percent of basidiomycete proteins are unique to the phylum with nearly half of those (22percent) found in only one organism. Correlations between lifestyle and certain gene families are evident. Phylogenetic patterns of plant biomass-degrading genes in Agaricomycotina suggest a continuum rather than a dichotomy between the white rot and brown rot modes of wood decay. Based on phylogenetically-informed PCA analysis of wood decay genes, we predict that that Botryobasidium botryosum and Jaapia argillacea have properties similar to white rot species, although neither has typical ligninolytic class II fungal peroxidases (PODs). This prediction is supported by growth assays in which both fungi exhibit wood decay with white rot-like characteristics. Based on this, we suggest that the white/brown rot dichotomy may be inadequate to describe the full range of wood decaying fungi. Analysis of the rate of discovery of proteins with no or few homologs suggests the value of continued sequencing of basidiomycete fungi.

  4. Rating locomotive crew diesel emission exposure profiles using statistics and Bayesian Decision Analysis.

    PubMed

    Hewett, Paul; Bullock, William H

    2014-01-01

    For more than 20 years CSX Transportation (CSXT) has collected exposure measurements from locomotive engineers and conductors who are potentially exposed to diesel emissions. The database included measurements for elemental and total carbon, polycyclic aromatic hydrocarbons, aromatics, aldehydes, carbon monoxide, and nitrogen dioxide. This database was statistically analyzed and summarized, and the resulting statistics and exposure profiles were compared to relevant occupational exposure limits (OELs) using both parametric and non-parametric descriptive and compliance statistics. Exposure ratings, using the American Industrial Health Association (AIHA) exposure categorization scheme, were determined using both the compliance statistics and Bayesian Decision Analysis (BDA). The statistical analysis of the elemental carbon data (a marker for diesel particulate) strongly suggests that the majority of levels in the cabs of the lead locomotives (n = 156) were less than the California guideline of 0.020 mg/m(3). The sample 95th percentile was roughly half the guideline; resulting in an AIHA exposure rating of category 2/3 (determined using BDA). The elemental carbon (EC) levels in the trailing locomotives tended to be greater than those in the lead locomotive; however, locomotive crews rarely ride in the trailing locomotive. Lead locomotive EC levels were similar to those reported by other investigators studying locomotive crew exposures and to levels measured in urban areas. Lastly, both the EC sample mean and 95%UCL were less than the Environmental Protection Agency (EPA) reference concentration of 0.005 mg/m(3). With the exception of nitrogen dioxide, the overwhelming majority of the measurements for total carbon, polycyclic aromatic hydrocarbons, aromatics, aldehydes, and combustion gases in the cabs of CSXT locomotives were either non-detects or considerably less than the working OELs for the years represented in the database. When compared to the previous American

  5. Exposure-Response Analysis and Risk Assessment for Lung Cancer in Relationship to Silica Exposure: A 44-Year Cohort Study of 34,018 Workers

    PubMed Central

    Liu, Yuewei; Steenland, Kyle; Rong, Yi; Hnizdo, Eva; Huang, Xiji; Zhang, Hai; Shi, Tingming; Sun, Yi; Wu, Tangchun; Chen, Weihong

    2015-01-01

    Crystalline silica has been classified as a human carcinogen by the International Agency for Research on Cancer (Lyon, France); however, few previous studies have provided quantitative data on silica exposure, silicosis, and/or smoking. We investigated a cohort in China (in 1960–2003) of 34,018 workers without exposure to carcinogenic confounders. Cumulative silica exposure was estimated by linking a job-exposure matrix to work history. Cox proportional hazards model was used to conduct exposure-response analysis and risk assessment. During a mean 34.5-year follow-up, 546 lung cancer deaths were identified. Categorical analyses by quartiles of cumulative silica exposure (using a 25-year lag) yielded hazard ratios of 1.26, 1.54, 1.68, and 1.70, respectively, compared with the unexposed group. Monotonic exposure-response trends were observed among nonsilicotics (P for trend < 0.001). Analyses using splines showed similar trends. The joint effect of silica and smoking was more than additive and close to multiplicative. For workers exposed from ages 20 to 65 years at 0.1 mg/m3 of silica exposure, the estimated excess lifetime risk (through age 75 years) was 0.51%. These findings confirm silica as a human carcinogen and suggest that current exposure limits in many countries might be insufficient to protect workers from lung cancer. They also indicate that smoking cessation could help reduce lung cancer risk for silica-exposed individuals. PMID:24043436

  6. Quantitative Plasma Biomarker Analysis in HDI Exposure Assessment

    PubMed Central

    Flack, Sheila L.; Fent, Kenneth W.; Trelles Gaines, Linda G.; Thomasen, Jennifer M.; Whittaker, Steve; Ball, Louise M.; Nylander-French, Leena A.

    2010-01-01

    Quantification of amines in biological samples is important for evaluating occupational exposure to diisocyanates. In this study, we describe the quantification of 1,6-hexamethylene diamine (HDA) levels in hydrolyzed plasma of 46 spray painters applying 1,6-hexamethylene diisocyanate (HDI)-containing paint in vehicle repair shops collected during repeated visits to their workplace and their relationship with dermal and inhalation exposure to HDI monomer. HDA was detected in 76% of plasma samples, as heptafluorobutyryl derivatives, and the range of HDA concentrations was ≤0.02–0.92 μg l−1. After log-transformation of the data, the correlation between plasma HDA levels and HDI inhalation exposure measured on the same workday was low (N = 108, r = 0.22, P = 0.026) compared with the correlation between plasma HDA levels and inhalation exposure occurring ∼20 to 60 days before blood collection (N = 29, r = 0.57, P = 0.0014). The correlation between plasma HDA levels and HDI dermal exposure measured on the same workday, although statistically significant, was low (N = 108, r = 0.22, P = 0.040) while the correlation between HDA and dermal exposure occurring ∼20 to 60 days before blood collection was slightly improved (N = 29, r = 0.36, P = 0.053). We evaluated various workplace factors and controls (i.e. location, personal protective equipment use and paint booth type) as modifiers of plasma HDA levels. Workers using a downdraft-ventilated booth had significantly lower plasma HDA levels relative to semi-downdraft and crossdraft booth types (P = 0.0108); this trend was comparable to HDI inhalation and dermal exposure levels stratified by booth type. These findings indicate that HDA concentration in hydrolyzed plasma may be used as a biomarker of cumulative inhalation and dermal exposure to HDI and for investigating the effectiveness of exposure controls in the workplace. PMID:19805392

  7. Space Shuttle and Space Station Radio Frequency (RF) Exposure Analysis

    NASA Technical Reports Server (NTRS)

    Hwu, Shian U.; Loh, Yin-Chung; Sham, Catherine C.; Kroll, Quin D.

    2005-01-01

    This paper outlines the modeling techniques and important parameters to define a rigorous but practical procedure that can verify the compliance of RF exposure to the NASA standards for astronauts and electronic equipment. The electromagnetic modeling techniques are applied to analyze RF exposure in Space Shuttle and Space Station environments with reasonable computing time and resources. The modeling techniques are capable of taking into account the field interactions with Space Shuttle and Space Station structures. The obtained results illustrate the multipath effects due to the presence of the space vehicle structures. It's necessary to include the field interactions with the space vehicle in the analysis for an accurate assessment of the RF exposure. Based on the obtained results, the RF keep out zones are identified for appropriate operational scenarios, flight rules and necessary RF transmitter constraints to ensure a safe operating environment and mission success.

  8. Internal exposure from building materials exhaling (222)Rn and (220)Rn as compared to external exposure due to their natural radioactivity content.

    PubMed

    Ujić, Predrag; Celiković, Igor; Kandić, Aleksandar; Vukanac, Ivana; Durasević, Mirjana; Dragosavac, Dusan; Zunić, Zora S

    2010-01-01

    The main scope of this paper is to point out the importance of introducing radon and thoron exhalation measurements from building materials in the regulating frame. Currently (2009), such a regulation of this kind of exposure is not explicitly included in the Serbian regulating network. To this end, this work reports concentration measurements of (226)Ra, (232)Th and (40)K and radon and thoron exhalation rates from building materials used in Serbia. Following detailed analysis, it was noticed that both internal exposures to radon and/or thoron exhaling from building materials may exceed external exposures to their precursors contained therein.

  9. Mendelian randomization analysis of a time-varying exposure for binary disease outcomes using functional data analysis methods.

    PubMed

    Cao, Ying; Rajan, Suja S; Wei, Peng

    2016-12-01

    A Mendelian randomization (MR) analysis is performed to analyze the causal effect of an exposure variable on a disease outcome in observational studies, by using genetic variants that affect the disease outcome only through the exposure variable. This method has recently gained popularity among epidemiologists given the success of genetic association studies. Many exposure variables of interest in epidemiological studies are time varying, for example, body mass index (BMI). Although longitudinal data have been collected in many cohort studies, current MR studies only use one measurement of a time-varying exposure variable, which cannot adequately capture the long-term time-varying information. We propose using the functional principal component analysis method to recover the underlying individual trajectory of the time-varying exposure from the sparsely and irregularly observed longitudinal data, and then conduct MR analysis using the recovered curves. We further propose two MR analysis methods. The first assumes a cumulative effect of the time-varying exposure variable on the disease risk, while the second assumes a time-varying genetic effect and employs functional regression models. We focus on statistical testing for a causal effect. Our simulation studies mimicking the real data show that the proposed functional data analysis based methods incorporating longitudinal data have substantial power gains compared to standard MR analysis using only one measurement. We used the Framingham Heart Study data to demonstrate the promising performance of the new methods as well as inconsistent results produced by the standard MR analysis that relies on a single measurement of the exposure at some arbitrary time point.

  10. Isocyanate and VOC exposure analysis using Flexane®.

    PubMed

    Blake, Charles L; Johnson, Giffe T; Abritis, Alison J; Lieckfield, Robert; Harbison, Raymond D

    2012-08-01

    Flexane® 80 is a trowelable urethane product used in combination with cleaners and primers to effect rubber conveyor belt repairs. These products are of concern due to the potential for worker exposure to isocyanates and volatile organic compounds (VOCs). Small chamber experiments were used to identify chemicals liberated to the ambient air from each of the Flexane®-related products. A new sample collection method using treated cotton sleeves as a surrogate skin surface to assess potential dermal exposure to isocyanates during mixing and application of the Flexane® product was validated. Six simulations of a worst case scenario were performed by an experienced belt repair technician in a walk-in laboratory exposure chamber. Analysis of air samples from the large chamber simulations did not detect airborne isocyanates. The average airborne VOC concentrations were below established occupational exposure levels. Dermal sleeve samples detected intermittent and low levels of isocyanates from self-application while wearing gloves having surface residues of uncured Flexane®. The data strongly suggest that the normal and intended use of Flexane® putty, and its associated products under worst case or typical working conditions is not likely to result in worker VOC or isocyanate exposure levels sufficient to produce adverse health effects.

  11. Comparative Genome Analysis of Basidiomycete Fungi

    SciTech Connect

    Riley, Robert; Salamov, Asaf; Morin, Emmanuelle; Nagy, Laszlo; Manning, Gerard; Baker, Scott; Brown, Daren; Henrissat, Bernard; Levasseur, Anthony; Hibbett, David; Martin, Francis; Grigoriev, Igor

    2012-03-19

    Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes the mushrooms, wood rots, symbionts, and plant and animal pathogens. To better understand the diversity of phenotypes in basidiomycetes, we performed a comparative analysis of 35 basidiomycete fungi spanning the diversity of the phylum. Phylogenetic patterns of lignocellulose degrading genes suggest a continuum rather than a sharp dichotomy between the white rot and brown rot modes of wood decay. Patterns of secondary metabolic enzymes give additional insight into the broad array of phenotypes found in the basidiomycetes. We suggest that the profile of an organism in lignocellulose-targeting genes can be used to predict its nutritional mode, and predict Dacryopinax sp. as a brown rot; Botryobasidium botryosum and Jaapia argillacea as white rots.

  12. Comparative analysis of the feline immunoglobulin repertoire.

    PubMed

    Steiniger, Sebastian C J; Glanville, Jacob; Harris, Douglas W; Wilson, Thomas L; Ippolito, Gregory C; Dunham, Steven A

    2017-01-25

    Next-Generation Sequencing combined with bioinformatics is a powerful tool for analyzing the large number of DNA sequences present in the expressed antibody repertoire and these data sets can be used to advance a number of research areas including antibody discovery and engineering. The accurate measurement of the immune repertoire sequence composition, diversity and abundance is important for understanding the repertoire response in infections, vaccinations and cancer immunology and could also be useful for elucidating novel molecular targets. In this study 4 individual domestic cats (Felis catus) were subjected to antibody repertoire sequencing with total number of sequences generated 1079863 for VH for IgG, 1050824 VH for IgM, 569518 for VK and 450195 for VL. Our analysis suggests that a similar VDJ expression patterns exists across all cats. Similar to the canine repertoire, the feline repertoire is dominated by a single subgroup, namely VH3. The antibody paratope of felines showed similar amino acid variation when compared to human, mouse and canine counterparts. All animals show a similarly skewed VH CDR-H3 profile and, when compared to canine, human and mouse, distinct differences are observed. Our study represents the first attempt to characterize sequence diversity in the expressed feline antibody repertoire and this demonstrates the utility of using NGS to elucidate entire antibody repertoires from individual animals. These data provide significant insight into understanding the feline immune system function.

  13. Comparative analysis of selected fuel cell vehicles

    SciTech Connect

    1993-05-07

    Vehicles powered by fuel cells operate more efficiently, more quietly, and more cleanly than internal combustion engines (ICEs). Furthermore, methanol-fueled fuel cell vehicles (FCVs) can utilize major elements of the existing fueling infrastructure of present-day liquid-fueled ICE vehicles (ICEVs). DOE has maintained an active program to stimulate the development and demonstration o fuel cell technologies in conjunction with rechargeable batteries in road vehicles. The purpose of this study is to identify and assess the availability of data on FCVs, and to develop a vehicle subsystem structure that can be used to compare both FCVs and ICEV, from a number of perspectives--environmental impacts, energy utilization, materials usage, and life cycle costs. This report focuses on methanol-fueled FCVs fueled by gasoline, methanol, and diesel fuel that are likely to be demonstratable by the year 2000. The comparative analysis presented covers four vehicles--two passenger vehicles and two urban transit buses. The passenger vehicles include an ICEV using either gasoline or methanol and an FCV using methanol. The FCV uses a Proton Exchange Membrane (PEM) fuel cell, an on-board methanol reformer, mid-term batteries, and an AC motor. The transit bus ICEV was evaluated for both diesel and methanol fuels. The transit bus FCV runs on methanol and uses a Phosphoric Acid Fuel Cell (PAFC) fuel cell, near-term batteries, a DC motor, and an on-board methanol reformer. 75 refs.

  14. Comparative metagenome analysis of an Alaskan glacier.

    PubMed

    Choudhari, Sulbha; Lohia, Ruchi; Grigoriev, Andrey

    2014-04-01

    The temperature in the Arctic region has been increasing in the recent past accompanied by melting of its glaciers. We took a snapshot of the current microbial inhabitation of an Alaskan glacier (which can be considered as one of the simplest possible ecosystems) by using metagenomic sequencing of 16S rRNA recovered from ice/snow samples. Somewhat contrary to our expectations and earlier estimates, a rich and diverse microbial population of more than 2,500 species was revealed including several species of Archaea that has been identified for the first time in the glaciers of the Northern hemisphere. The most prominent bacterial groups found were Proteobacteria, Bacteroidetes, and Firmicutes. Firmicutes were not reported in large numbers in a previously studied Alpine glacier but were dominant in an Antarctic subglacial lake. Representatives of Cyanobacteria, Actinobacteria and Planctomycetes were among the most numerous, likely reflecting the dependence of the ecosystem on the energy obtained through photosynthesis and close links with the microbial community of the soil. Principal component analysis (PCA) of nucleotide word frequency revealed distinct sequence clusters for different taxonomic groups in the Alaskan glacier community and separate clusters for the glacial communities from other regions of the world. Comparative analysis of the community composition and bacterial diversity present in the Byron glacier in Alaska with other environments showed larger overlap with an Arctic soil than with a high Arctic lake, indicating patterns of community exchange and suggesting that these bacteria may play an important role in soil development during glacial retreat.

  15. Comparative Sensitivity Analysis of Muscle Activation Dynamics

    PubMed Central

    Rockenfeller, Robert; Günther, Michael; Schmitt, Syn; Götz, Thomas

    2015-01-01

    We mathematically compared two models of mammalian striated muscle activation dynamics proposed by Hatze and Zajac. Both models are representative for a broad variety of biomechanical models formulated as ordinary differential equations (ODEs). These models incorporate parameters that directly represent known physiological properties. Other parameters have been introduced to reproduce empirical observations. We used sensitivity analysis to investigate the influence of model parameters on the ODE solutions. In addition, we expanded an existing approach to treating initial conditions as parameters and to calculating second-order sensitivities. Furthermore, we used a global sensitivity analysis approach to include finite ranges of parameter values. Hence, a theoretician striving for model reduction could use the method for identifying particularly low sensitivities to detect superfluous parameters. An experimenter could use it for identifying particularly high sensitivities to improve parameter estimation. Hatze's nonlinear model incorporates some parameters to which activation dynamics is clearly more sensitive than to any parameter in Zajac's linear model. Other than Zajac's model, Hatze's model can, however, reproduce measured shifts in optimal muscle length with varied muscle activity. Accordingly we extracted a specific parameter set for Hatze's model that combines best with a particular muscle force-length relation. PMID:26417379

  16. Comparative Analysis of Genome Sequences with VISTA

    DOE Data Explorer

    Dubchak, Inna

    VISTA is a comprehensive suite of programs and databases developed by and hosted at the Genomics Division of Lawrence Berkeley National Laboratory. They provide information and tools designed to facilitate comparative analysis of genomic sequences. Users have two ways to interact with the suite of applications at the VISTA portal. They can submit their own sequences and alignments for analysis (VISTA servers) or examine pre-computed whole-genome alignments of different species. A key menu option is the Enhancer Browser and Database at http://enhancer.lbl.gov/. The VISTA Enhancer Browser is a central resource for experimentally validated human noncoding fragments with gene enhancer activity as assessed in transgenic mice. Most of these noncoding elements were selected for testing based on their extreme conservation with other vertebrates. The results of this enhancer screen are provided through this publicly available website. The browser also features relevant results by external contributors and a large collection of additional genome-wide conserved noncoding elements which are candidate enhancer sequences. The LBL developers invite external groups to submit computational predictions of developmental enhancers. As of 10/19/2009 the database contains information on 1109 in vivo tested elements - 508 elements with enhancer activity.

  17. [Exposure to environmental tobacco smoke in pre-school children--a comparative study].

    PubMed

    Bielskai, Dorota Emilia; Gomółka, Ewa; Kurpas, Donata; Chlabicz, Slawomir

    2015-01-01

    The objective of the work was to compare the socioeconomic situation and the structure of tobacco use in the families of children attending preschools in Bialystok in 2004 and 2012 in terms of 3-year-olds' exposure to environmental tobacco smoke (ETS). The study involved 313 children out of 1,200 3-year-olds attending 51 pre-schools in Bialystok in 2004 (Gr I) and 273 children out of 1,100 attending 49 pre-schools in 2012 (Gr I). Information on environmental conditions and the use of tobacco in the families of the studied 3-year-olds was obtained through anonymous questionnaires filled in by their parents or caregivers. The exposure of children to ETS was evaluated using the questionnaire and by determining the cotinine/creatinine ratio in urine. The children from Gr I had better educated (p<0.001) and wealthier (p=0.005) parents, and better living conditions (p=0.008). In 47.3% of the homes of children from Gr I and 31.1% of homes of children from Gr II there was at least one smoking person (p<0.001). Both in 2004 and in 2012, fathers prevailed among the smokers, but in 2012 their number was significantly lower (p<0.001). As for mothers, 23.6% of them in Gr I and 10.3% in Gr I admitted smoking every day (p<0.001). More children from Gr I than from Gr I lived with smoking grandparents. The declared number of cigarettes smoked a day by the people living with the children was similar in both Groups The Groups did not differ significantly regarding the rules of tobacco smoke applying to the family members and guests (p=0.639). The mean cotinine/ creatinine concentration [ng/mg] in the urine of children from Gr I (60.78) was significantly higher than in those from Gr II (22.75) (p<0.001). According to the survey data, in 2012 fewer three-year-olds were exposed to ETS out of home (p<0.001). The mean cotinine/ creatinine concentrations [ng/mg] depending on the declared exposure to tobacco smoke out of home: no exposure, existing exposure, unknown exposure, were for Gr I

  18. Occupational exposure to electromagnetic fields and acute leukaemia: analysis of a case-control study

    PubMed Central

    Willett, E; McKinney, P; Fear, N; Cartwright, R; Roman, E

    2003-01-01

    Aims: To investigate whether the risk of acute leukaemia among adults is associated with occupational exposure to electromagnetic fields. Methods: Probable occupational exposure to electromagnetic fields at higher than typical residential levels was investigated among 764 patients diagnosed with acute leukaemia during 1991–96 and 1510 sex and age matched controls. A job exposure matrix was applied to the self reported employment histories to determine whether or not a subject was exposed to electromagnetic fields. Risks were assessed using conditional logistic regression for a matched analysis. Results: Study subjects considered probably ever exposed to electromagnetic fields at work were not at increased risk of acute leukaemia compared to those considered never exposed. Generally, no associations were observed on stratification by sex, leukaemia subtype, number of years since exposure stopped, or occupation; there was no evidence of a dose-response effect using increasing number of years exposed. However, relative to women considered never exposed, a significant excess of acute lymphoblastic leukaemia was observed among women probably exposed to electromagnetic fields at work that remained increased irrespective of time prior to diagnosis or job ever held. Conclusion: This large population based case-control study found little evidence to support an association between occupational exposure to electromagnetic fields and acute leukaemia. While an excess of acute lymphoblastic leukaemia among women was observed, it is unlikely that occupational exposure to electromagnetic fields was responsible, given that increased risks remained during periods when exposure above background levels was improbable. PMID:12883018

  19. Comparative risk assessment of carcinogens in alcoholic beverages using the margin of exposure approach.

    PubMed

    Lachenmeier, Dirk W; Przybylski, Maria C; Rehm, Jürgen

    2012-09-15

    Alcoholic beverages have been classified as carcinogenic to humans. As alcoholic beverages are multicomponent mixtures containing several carcinogenic compounds, a quantitative approach is necessary to compare the risks. Fifteen known and suspected human carcinogens (acetaldehyde, acrylamide, aflatoxins, arsenic, benzene, cadmium, ethanol, ethyl carbamate, formaldehyde, furan, lead, 4-methylimidazole, N-nitrosodimethylamine, ochratoxin A and safrole) occurring in alcoholic beverages were identified based on monograph reviews by the International Agency for Research on Cancer. The margin of exposure (MOE) approach was used for comparative risk assessment. MOE compares a toxicological threshold with the exposure. MOEs above 10,000 are judged as low priority for risk management action. MOEs were calculated for different drinking scenarios (low risk and heavy drinking) and different levels of contamination for four beverage groups (beer, wine, spirits and unrecorded alcohol). The lowest MOEs were found for ethanol (3.1 for low risk and 0.8 for heavy drinking). Inorganic lead and arsenic have average MOEs between 10 and 300, followed by acetaldehyde, cadmium and ethyl carbamate between 1,000 and 10,000. All other compounds had average MOEs above 10,000 independent of beverage type. Ethanol was identified as the most important carcinogen in alcoholic beverages, with clear dose response. Some other compounds (lead, arsenic, ethyl carbamate, acetaldehyde) may pose risks below thresholds normally tolerated for food contaminants, but from a cost-effectiveness point of view, the focus should be on reducing alcohol consumption in general rather than on mitigative measures for some contaminants that contribute only to a limited extent (if at all) to the total health risk.

  20. TRIAGE DOSE ASSESSMENT FOR PARTIAL-BODY EXPOSURE: DICENTRIC ANALYSIS

    PubMed Central

    Moroni, Maria; Pellmar, Terry C.

    2009-01-01

    Partial-body biodosimetry is likely to be required after a radiological or nuclear exposure. Clinical signs and symptoms, distribution of dicentrics in circulating blood cells, organ-specific biomarkers, physical signals in teeth and nails all can provide indications of non-homogeneous exposures. Organ specific biomarkers may provide early warning regarding physiological systems at risk after radiation injury. Use of a combination of markers and symptoms will be needed for clinical insights for therapeutic approaches. Analysis of dicentrics, a marker specific for radiation injury, is the “Gold standard” of biodosimetry and can reveal partial-body exposures. Automation of sample processing for dicentric analysis can increase throughput with customization of off-the-shelf technologies for cytogenetic sample processing and information management. Automated analysis of the metaphase spreads is currently limited but improvements are in development. Our efforts bridge the technological gaps to allow the use of dicentric chromosome assay (DCA) for risk-based stratification of mass casualties. This article summarizes current knowledge on partial-body cytogenetic dose assessment synthesizing information leading to the proposal of an approach to triage dose prediction in radiation mass casualties, based on equivalent whole-body doses under partial-body exposure conditions and assesses the validity of using this model. An initial screening using only 20 metaphase spreads per subject can confirm irradiation above 2-Gy. A subsequent increase to 50 metaphases improves dose determination to allow risk stratification for clinical triage. Metaphases evaluated for inhomogeneous distribution of dicentrics can reveal partial-body exposures. We tested the validity of this approach in an in vitro model that simulates partial-body irradiation by mixing irradiated and un-irradiated lymphocytes in various proportions. Our preliminary results support the notion that this approach will

  1. Causal mediation analysis for longitudinal data with exogenous exposure

    PubMed Central

    Bind, M.-A. C.; Vanderweele, T. J.; Coull, B. A.; Schwartz, J. D.

    2016-01-01

    Mediation analysis is a valuable approach to examine pathways in epidemiological research. Prospective cohort studies are often conducted to study biological mechanisms and often collect longitudinal measurements on each participant. Mediation formulae for longitudinal data have been developed. Here, we formalize the natural direct and indirect effects using a causal framework with potential outcomes that allows for an interaction between the exposure and the mediator. To allow different types of longitudinal measures of the mediator and outcome, we assume two generalized mixed-effects models for both the mediator and the outcome. The model for the mediator has subject-specific random intercepts and random exposure slopes for each cluster, and the outcome model has random intercepts and random slopes for the exposure, the mediator, and their interaction. We also expand our approach to settings with multiple mediators and derive the mediated effects, jointly through all mediators. Our method requires the absence of time-varying confounding with respect to the exposure and the mediator. This assumption is achieved in settings with exogenous exposure and mediator, especially when exposure and mediator are not affected by variables measured at earlier time points. We apply the methodology to data from the Normative Aging Study and estimate the direct and indirect effects, via DNA methylation, of air pollution, and temperature on intercellular adhesion molecule 1 (ICAM-1) protein levels. Our results suggest that air pollution and temperature have a direct effect on ICAM-1 protein levels (i.e. not through a change in ICAM-1 DNA methylation) and that temperature has an indirect effect via a change in ICAM-1 DNA methylation. PMID:26272993

  2. Comparative toxicity of low dose tributyltin chloride on serum, liver, lung and kidney following subchronic exposure.

    PubMed

    Mitra, Sumonto; Gera, Ruchi; Singh, Vikas; Khandelwal, Shashi

    2014-02-01

    Tributyltin (TBT) pollution is rampant worldwide and is a growing threat due to its bio-accumulative property. Isolated studies of TBT toxicity on different organs are available but consolidated information is greatly lacking. We planned this study to delineate the effect of subchronic (1 month) exposure to low dose TBT-chloride (TBTC) (1 and 5 mg/kg) in male Wistar rats. Total tin concentration was found to be significantly increased in liver, kidney and blood, and marginally in lungs. Organo-somatic indices were seen to be altered with little effect on serum biochemical markers (liver and kidney function, and general parameters). Reactive oxygen species but not lipid peroxidation content was observed to be significantly elevated both in the tissues and serum. TBTC was found to act as a hyperlipidemic agent and it also affected heme biosynthetic pathway. Hematological analysis showed that TBTC exposure resulted in minor alterations in RBC parameters. Histological studies demonstrated marked tissue damage in all the 3 organs. Calcium inhibitors (BAPTA-AM, EGTA) and antioxidants (NAC, C-PC) significantly restored TBTC induced loss in cell viability, under ex-vivo conditions. Antioxidants were evidently more efficient in comparison to the calcium inhibitors, implying major role of oxidative stress pathways in TBTC toxicity.

  3. Predictive and comparative analysis of Ebolavirus proteins

    PubMed Central

    Cong, Qian; Pei, Jimin; Grishin, Nick V

    2015-01-01

    Ebolavirus is the pathogen for Ebola Hemorrhagic Fever (EHF). This disease exhibits a high fatality rate and has recently reached a historically epidemic proportion in West Africa. Out of the 5 known Ebolavirus species, only Reston ebolavirus has lost human pathogenicity, while retaining the ability to cause EHF in long-tailed macaque. Significant efforts have been spent to determine the three-dimensional (3D) structures of Ebolavirus proteins, to study their interaction with host proteins, and to identify the functional motifs in these viral proteins. Here, in light of these experimental results, we apply computational analysis to predict the 3D structures and functional sites for Ebolavirus protein domains with unknown structure, including a zinc-finger domain of VP30, the RNA-dependent RNA polymerase catalytic domain and a methyltransferase domain of protein L. In addition, we compare sequences of proteins that interact with Ebolavirus proteins from RESTV-resistant primates with those from RESTV-susceptible monkeys. The host proteins that interact with GP and VP35 show an elevated level of sequence divergence between the RESTV-resistant and RESTV-susceptible species, suggesting that they may be responsible for host specificity. Meanwhile, we detect variable positions in protein sequences that are likely associated with the loss of human pathogenicity in RESTV, map them onto the 3D structures and compare their positions to known functional sites. VP35 and VP30 are significantly enriched in these potential pathogenicity determinants and the clustering of such positions on the surfaces of VP35 and GP suggests possible uncharacterized interaction sites with host proteins that contribute to the virulence of Ebolavirus. PMID:26158395

  4. Minimalist models for proteins: a comparative analysis.

    PubMed

    Tozzini, Valentina

    2010-08-01

    The last decade has witnessed a renewed interest in the coarse-grained (CG) models for biopolymers, also stimulated by the needs of modern molecular biology, dealing with nano- to micro-sized bio-molecular systems and larger than microsecond timescale. This combination of size and timescale is, in fact, hard to access by atomic-based simulations. Coarse graining the system is a route to be followed to overcome these limits, but the ways of practically implementing it are many and different, making the landscape of CG models very vast and complex. In this paper, the CG models are reviewed and their features, applications and performances compared. This analysis, restricted to proteins, focuses on the minimalist models, namely those reducing at minimum the number of degrees of freedom without losing the possibility of explicitly describing the secondary structures. This class includes models using a single or a few interacting centers (beads) for each amino acid. From this analysis several issues emerge. The difficulty in building these models resides in the need for combining transferability/predictive power with the capability of accurately reproducing the structures. It is shown that these aspects could be optimized by accurately choosing the force field (FF) terms and functional forms, and combining different parameterization procedures. In addition, in spite of the variety of the minimalist models, regularities can be found in the parameters values and in FF terms. These are outlined and schematically presented with the aid of a generic phase diagram of the polypeptide in the parameter space and, hopefully, could serve as guidelines for the development of minimalist models incorporating the maximum possible level of predictive power and structural accuracy.

  5. Comparative study of spermatogonial survival after X-ray exposure, high LET (HZE) irradiation or spaceflight

    NASA Technical Reports Server (NTRS)

    Sapp, W. J.; Williams, C. S.; Williams, J. W.; Philpott, D. E.; Kato, K.; Miquel, J. M.; Serova, L.

    1992-01-01

    Spermatogonial cell loss has been observed in rats flown on Space Lab 3, Cosmos 1887, Cosmos 2044 and in mice following irradiation with X-ray or with HZE particle beams. Spermatogonial loss is determined by cell counting in maturation stage-6 seminferous tubules. With the exception of iron, laboratory irradiation experiments (with mice) revealed a similar pattern of spermatogonial loss proportional to the radiation dose at levels less than 0.1 Gy. Helium and argon irradiation resulted in a 5-percent loss of spermatogonia after only 0.01 Gy exposure. Significant spermatogonial loss (45 percent) occurred at this radiation level with iron particle beams. The loss of spermatogonia during each spaceflight was less than 10 percent when compared to control (nonflight) animals.

  6. Comparative genomic analysis of prion genes

    PubMed Central

    Premzl, Marko; Gamulin, Vera

    2007-01-01

    Background The homologues of human disease genes are expected to contribute to better understanding of physiological and pathogenic processes. We made use of the present availability of vertebrate genomic sequences, and we have conducted the most comprehensive comparative genomic analysis of the prion protein gene PRNP and its homologues, shadow of prion protein gene SPRN and doppel gene PRND, and prion testis-specific gene PRNT so far. Results While the SPRN and PRNP homologues are present in all vertebrates, PRND is known in tetrapods, and PRNT is present in primates. PRNT could be viewed as a TE-associated gene. Using human as the base sequence for genomic sequence comparisons (VISTA), we annotated numerous potential cis-elements. The conserved regions in SPRNs harbour the potential Sp1 sites in promoters (mammals, birds), C-rich intron splicing enhancers and PTB intron splicing silencers in introns (mammals, birds), and hsa-miR-34a sites in 3'-UTRs (eutherians). We showed the conserved PRNP upstream regions, which may be potential enhancers or silencers (primates, dog). In the PRNP 3'-UTRs, there are conserved cytoplasmic polyadenylation element sites (mammals, birds). The PRND core promoters include highly conserved CCAAT, CArG and TATA boxes (mammals). We deduced 42 new protein primary structures, and performed the first phylogenetic analysis of all vertebrate prion genes. Using the protein alignment which included 122 sequences, we constructed the neighbour-joining tree which showed four major clusters, including shadoos, shadoo2s and prion protein-likes (cluster 1), fish prion proteins (cluster 2), tetrapode prion proteins (cluster 3) and doppels (cluster 4). We showed that the entire prion protein conformationally plastic region is well conserved between eutherian prion proteins and shadoos (18–25% identity and 28–34% similarity), and there could be a potential structural compatibility between shadoos and the left-handed parallel beta-helical fold

  7. Comparative toxicities of bismuth oxybromide and titanium dioxide exposure on human skin keratinocyte cells.

    PubMed

    Gao, Xiaoya; Wang, Yawen; Peng, Shiqi; Yue, Bin; Fan, Caimei; Chen, Weiyi; Li, Xiaona

    2015-09-01

    Nano-sized bismuth oxybromide (BiOBr) particles are being considered for applications within the semiconductor industry. However, little is known about their potential impact on human health. In this study, we comparatively investigated the cytotoxicity of BiOBr and titanium dioxide (TiO2) nanoparticles (NPs) using human skin keratinocyte cell line (HaCaT) as a research model. Results indicate that lamellar-shaped BiOBr (length: 200 nm, width: 150 nm, and an average thickness: around 15 nm) has less toxic effects on cell viability and intracellular organelles than TiO2 (P25) NPs. BiOBr mainly induced late cell apoptosis, while for TiO2, both early apoptosis and late apoptosis were involved. Cell cycle arrest was found in cells on both NPs exposure, and more prominent in TiO2-treated cells. More cellular uptake was achieved after TiO2 exposure, particularly at 10 μg mL(-1), presence of TiO2 resulted in more than 2-fold increase in cellular granularity compared with BiOBr. Furthermore, TiO2 had a high potential to generate intracellular reactive oxygen species (ROS) in cells, where a 2.7-fold increase in TiO2 group and 2.0-fold increase in BiOBr group at the same concentration of 25 μg mL(-1). Higher cellular uptake and ROS stimulation should contribute to the more hazards of TiO2 than BiOBr NPs. This knowledge is a crucial component in the environmental and human hazard assessment of BiOBr and TiO2 NPs.

  8. Comparing the results of five lifting analysis tools.

    PubMed

    Russell, Steven J; Winnemuller, Lori; Camp, Janice E; Johnson, Peter W

    2007-01-01

    The objective of this study was to compare the results of the NIOSH, ACGIH TLV, Snook, 3DSSPP and WA L&I lifting assessment instruments when applied to a uniform task (lifting and lowering milk cases with capacities of 15 and 23l). To enable comparisons between the various lifting assessment instruments, the outputs of each method were converted to an exposure index similar to the NIOSH Lifting Index. All instruments showed higher exposures associated with lifting the 23l cases versus the 15l cases. The NIOSH, ACGIH TLV and Snook methods were similar in their results with respect to the pattern of exposure over various height levels and the differences in exposures associated with lifting 15 and 23l cases. However, the WA L&I and 3DSSPP predicted substantially lower exposures. The reasons for instrument differences are presented so that practitioners can better select the methods they need and interpret the results appropriately.

  9. RECONSTRUCTING EXPOSURE SCENARIOS USING DOSE BIOMARKERS - AN APPLICATION OF BAYESIAN UNCERTAINTY ANALYSIS

    EPA Science Inventory

    We use Bayesian uncertainty analysis to explore how to estimate pollutant exposures from biomarker concentrations. The growing number of national databases with exposure data makes such an analysis possible. They contain datasets of pharmacokinetic biomarkers for many polluta...

  10. Comparing Results from Constant Comparative and Computer Software Methods: A Reflection about Qualitative Data Analysis

    ERIC Educational Resources Information Center

    Putten, Jim Vander; Nolen, Amanda L.

    2010-01-01

    This study compared qualitative research results obtained by manual constant comparative analysis with results obtained by computer software analysis of the same data. An investigated about issues of trustworthiness and accuracy ensued. Results indicated that the inductive constant comparative data analysis generated 51 codes and two coding levels…

  11. Biomonitoring of concurrent mycotoxin exposure among adults in Sweden through urinary multi-biomarker analysis.

    PubMed

    Wallin, S; Gambacorta, L; Kotova, N; Lemming, E Warensjö; Nälsén, C; Solfrizzo, M; Olsen, M

    2015-09-01

    Mycotoxin producing moulds may contaminate numerous agricultural commodities either before harvest or during storage. A varied diet consisting of different foods may therefore be contaminated with a range of mycotoxins. The aim of the present study was to study concurrent exposure to mycotoxins through urinary multi-biomarker analysis, as well as its possible associations with the diet. Urinary samples from 252 adults, participating in the Swedish national dietary survey Riksmaten 2010-11, were collected together with a 4-day diet record. Concurrent mycotoxin exposure was studied using a multi-biomarker LC-MS/MS method. The results revealed that exposure to mycotoxins is common and concurrent exposure to more than one toxin was found in 69% of the study population. However, when comparing the number of toxins detected with the reported consumption data it was difficult to distinguish food patterns which would indicate an increased risk of exposure to many mycotoxins simultaneously. This is the first study to investigate concurrent mycotoxin exposure and urinary levels of fumonisin B1 (FB1), fumonisin B2 (FB2), nivalenol (NIV), ochratoxin A (OTA), zearalenone (ZEA), α-zearalenol (α-ZOL), β-zearalenol (β-ZOL) and de-epoxydeoxynivalenol (DOM-1) among adults in Sweden.

  12. Quantitative proteomic analysis of the brainstem following lethal sarin exposure.

    PubMed

    Meade, Mitchell L; Hoffmann, Andrea; Makley, Meghan K; Snider, Thomas H; Schlager, John J; Gearhart, Jeffery M

    2015-06-22

    The brainstem represents a major tissue area affected by sarin organophosphate poisoning due to its function in respiratory and cardiovascular control. While the acute toxic effects of sarin on brainstem-related responses are relatively unknown, other brain areas e.g., cortex or cerebellum, have been studied more extensively. The study objective was to analyze the guinea pig brainstem toxicology response following sarin (2×LD50) exposure by proteome pathway analysis to gain insight into the complex regulatory mechanisms that lead to impairment of respiratory and cardiovascular control. Guinea pig exposure to sarin resulted in the typical acute behavior/physiology outcomes with death between 15 and 25min. In addition, brain and blood acetylcholinesterase activity was significantly reduced in the presence of sarin to 95%, and 89%, respectively, of control values. Isobaric-tagged (iTRAQ) liquid chromatography tandem mass spectrometry (LC-MS/MS) identified 198 total proteins of which 23% were upregulated, and 18% were downregulated following sarin exposure. Direct gene ontology (GO) analysis revealed a sarin-specific broad-spectrum proteomic profile including glutamate-mediated excitotoxicity, calcium overload, energy depletion responses, and compensatory carbohydrate metabolism, increases in ROS defense, DNA damage and chromatin remodeling, HSP response, targeted protein degradation (ubiquitination) and cell death response. With regards to the sarin-dependent effect on respiration, our study supports the potential interference of sarin with CO2/H(+) sensitive chemoreceptor neurons of the brainstem retrotrapezoid nucleus (RTN) that send excitatory glutamergic projections to the respiratory centers. In conclusion, this study gives insight into the brainstem broad-spectrum proteome following acute sarin exposure and the gained information will assist in the development of novel countermeasures.

  13. Comparative safety analysis of LNG storage tanks

    SciTech Connect

    Fecht, B.A.; Gates, T.E.; Nelson, K.O.; Marr, G.D.

    1982-07-01

    LNG storage tank design and response to selected release scenarios were reviewed. The selection of the scenarios was based on an investigation of potential hazards as cited in the literature. A review of the structure of specific LNG storage facilities is given. Scenarios initially addressed included those that most likely emerge from the tank facility itself: conditions of overfill and overflow as related to liquid LNG content levels; over/underpressurization at respective tank vapor pressure boundaries; subsidence of bearing soil below tank foundations; and crack propagation in tank walls due to possible exposure of structural material to cryogenic temperatures. Additional scenarios addressed include those that result from external events: tornado induced winds and pressure drops; exterior tank missile impact with tornado winds and rotating machinery being the investigated mode of generation; thermal response due to adjacent fire conditions; and tank response due to intense seismic activity. Applicability of each scenario depended heavily on the specific tank configurations and material types selected. (PSB)

  14. Human Capital Development: Comparative Analysis of BRICs

    ERIC Educational Resources Information Center

    Ardichvili, Alexandre; Zavyalova, Elena; Minina, Vera

    2012-01-01

    Purpose: The goal of this article is to conduct macro-level analysis of human capital (HC) development strategies, pursued by four countries commonly referred to as BRICs (Brazil, Russia, India, and China). Design/methodology/approach: This analysis is based on comparisons of macro indices of human capital and innovativeness of the economy and a…

  15. Solar ultraviolet and the occupational radiant exposure of Queensland school teachers: A comparative study between teaching classifications and behavior patterns.

    PubMed

    Downs, Nathan J; Harrison, Simone L; Chavez, Daniel R Garzon; Parisi, Alfio V

    2016-05-01

    Classroom teachers located in Queensland, Australia are exposed to high levels of ambient solar ultraviolet as part of the occupational requirement to provide supervision of children during lunch and break times. We investigated the relationship between periods of outdoor occupational radiant exposure and available ambient solar radiation across different teaching classifications and schools relative to the daily occupational solar ultraviolet radiation (HICNIRP) protection standard of 30J/m(2). Self-reported daily sun exposure habits (n=480) and personal radiant exposures were monitored using calibrated polysulphone dosimeters (n=474) in 57 teaching staff from 6 different schools located in tropical north and southern Queensland. Daily radiant exposure patterns among teaching groups were compared to the ambient UV-Index. Personal sun exposures were stratified among teaching classifications, school location, school ownership (government vs non-government), and type (primary vs secondary). Median daily radiant exposures were 15J/m(2) and 5J/m(2)HICNIRP for schools located in northern and southern Queensland respectively. Of the 474 analyzed dosimeter-days, 23.0% were found to exceed the solar radiation protection standard, with the highest prevalence found among physical education teachers (57.4% dosimeter-days), followed by teacher aides (22.6% dosimeter-days) and classroom teachers (18.1% dosimeter-days). In Queensland, peak outdoor exposure times of teaching staff correspond with periods of extreme UV-Index. The daily occupational HICNIRP radiant exposure standard was exceeded in all schools and in all teaching classifications.

  16. Question analysis for Indonesian comparative question

    NASA Astrophysics Data System (ADS)

    Saelan, A.; Purwarianti, A.; Widyantoro, D. H.

    2017-01-01

    Information seeking is one of human needs today. Comparing things using search engine surely take more times than search only one thing. In this paper, we analyzed comparative questions for comparative question answering system. Comparative question is a question that comparing two or more entities. We grouped comparative questions into 5 types: selection between mentioned entities, selection between unmentioned entities, selection between any entity, comparison, and yes or no question. Then we extracted 4 types of information from comparative questions: entity, aspect, comparison, and constraint. We built classifiers for classification task and information extraction task. Features used for classification task are bag of words, whether for information extraction, we used lexical, 2 previous and following words lexical, and previous label as features. We tried 2 scenarios: classification first and extraction first. For classification first, we used classification result as a feature for extraction. Otherwise, for extraction first, we used extraction result as features for classification. We found that the result would be better if we do extraction first before classification. For the extraction task, classification using SMO gave the best result (88.78%), while for classification, it is better to use naïve bayes (82.35%).

  17. New results from FRECOPA analysis. [long duration exposure facility

    NASA Technical Reports Server (NTRS)

    Durin, Christian

    1992-01-01

    Given Long Duration Exposure Facility (LDEF) new situation (5.8 years mission), CNES decided to set up a team to analyze FRECOPA systems (AO 138). We studied the kinematic system first. We observed damage on the DELRIN gears and lubricant ageing. The results are based on comparative appraisals between components after flight and those stored on ground in laboratory conditions. We observed also the aluminum surface treatment in the exposed areas and we measured the thermo-optical properties changes. Now, with all the results stored, we try to give a ruling on the use of FRECOPA materials in space environment.

  18. MANAGEMENT AND COMPARATIVE ANALYSIS OF DATASET ENSEMBLES

    SciTech Connect

    Geveci, Berk

    2010-05-17

    The primary Phase I technical objective was to develop a prototype that demonstrates the functionality of all components required for an end-to-end meta-data management and comparative visualization system.

  19. Comparative modeling approaches for personal exposure to particle-associated PAH.

    PubMed

    Aquilina, Noel J; Delgado-Saborit, Juana Mari; Gauci, Adam P; Baker, Stephen; Meddings, Claire; Harrison, Roy M

    2010-12-15

    Several models for simulation of personal exposure (PE) to particle-associated polycyclic aromatic hydrocarbons (PAH) have been developed and tested. The modeling approaches include linear regression models (Model 1), time activity weighted models (Models 2 and 3), a hybrid model (Model 4), a univariate linear model (Model 5), and machine learning technique models (Model 6 and 7). The hybrid model (Model 4), which utilizes microenvironment data derived from time-activity diaries (TAD) with the implementation of add-on variables to account for external factors that might affect PE, proved to be the best regression model (R(2) for B(a)P = 0.346, p < 0.01; N = 68). This model was compared with results from two machine learning techniques, namely decision trees (Model 6) and neural networks (Model 7), which represent an innovative approach to PE modeling. The neural network model was promising in giving higher correlation coefficient results for all PAH (R(2) for B(a)P = 0.567, p < 0.01; N = 68) and good performance with the smaller test data set (R(2) for B(a)P = 0.640, p < 0.01; N = 23). Decision tree accuracies (Model 6) which assess how precisely the algorithm can determine the correct classification of a PE concentration range indicate good performance, but this is not comparable to the other models through R(2) values. Using neural networks (Model 7) showed significant improvements over the performance of hybrid Model 4 and the univariate general linear Model 5 for test samples (not used in developing the models). The worst performance was given by linear regression Models 1 to 3 based solely on home and workplace concentrations and time-activity data.

  20. Comparative evaluation of nitrogen oxides and ozone passive diffusion tubes for exposure studies

    NASA Astrophysics Data System (ADS)

    Vardoulakis, Sotiris; Lumbreras, Julio; Solazzo, Efisio

    Passive diffusion tubes are recognised as a cost-effective sampling method for characterising the spatial variability, as well as the seasonal and annual trends, of NO 2 concentrations in urban areas. In addition, NO X and O 3 passive diffusion tubes have been developed and deployed in urban and rural areas. Despite their many advantages (e.g. low operational and analysis cost, small size and no need for power supply), they have certain limitations mainly related to their accuracy and precision. In particular, the absorbent solution used, the length of the exposure period, the exact location and use of protective devices, and other environmental conditions (e.g. wind, ambient temperature and relative humidity) may have a significant impact on the performance of passive diffusion tubes. The aim of this study is to evaluate the performance of co-located NO 2, NO X and O 3 diffusion tubes in an urban environment. A one-year passive sampling campaign was carried out in Birmingham (UK) for this purpose. NO 2, NO X and O 3 diffusion tubes (including triplicate sets of each) were co-located at one urban background and two roadside permanent air quality monitoring stations equipped with standard gas analysers. In addition, meteorological data, such as wind speed and direction, ambient temperature and relative humidity, were obtained during the same period of time. A thorough QA/QC procedure, including storage and laboratory blanks was followed throughout the campaign. The analysis of results showed a very good agreement of NO 2 passive samplers with co-located chemiluminescence analysers, but substantial underestimations of total NO X levels by the diffusion tubes. The O 3 diffusion sampler appeared to marginally overestimate the automatic UV analyser results, especially during warm weather periods.

  1. Assessments of direct human exposure: the approach of EU risk assessments compared to scenario-based risk assessment.

    PubMed

    Wormuth, Matthias; Demou, Evangelia; Scheringer, Martin; Hungerbühler, Konrad

    2007-08-01

    The awareness of potential risks emerging from the use of chemicals in all parts of daily life has increased the need for risk assessments that are able to cover a high number of exposure situations and thereby ensure the safety of workers and consumers. In the European Union (EU), the practice of risk assessments for chemicals is laid down in a Technical Guidance Document; it is designed to consider environmental and human occupational and residential exposure. Almost 70 EU risk assessment reports (RARs) have been finalized for high-production-volume chemicals during the last decade. In the present study, we analyze the assessment of occupational and consumer exposure to trichloroethylene and phthalates presented in six EU RARs. Exposure scenarios in these six RARs were compared to scenarios used in applications of the scenario-based risk assessment approach to the same set of chemicals. We find that scenarios used in the selected EU RARs to represent typical exposure situations in occupational or private use of chemicals and products do not necessarily represent worst-case conditions. This can be due to the use of outdated information on technical equipment and conditions in workplaces or omission of pathways that can cause consumer exposure. Considering the need for exposure and risk assessments under the new chemicals legislation of the EU, we suggest that a transparent process of collecting data on exposure situations and of generating representative exposure scenarios is implemented to improve the accuracy of risk assessments. Also, the data sets used to assess human exposure should be harmonized, summarized in a transparent fashion, and made accessible for all risk assessors and the public.

  2. Time profiles and toxicokinetic parameters of key biomarkers of exposure to cypermethrin in orally exposed volunteers compared with previously available kinetic data following permethrin exposure.

    PubMed

    Ratelle, Mylène; Coté, Jonathan; Bouchard, Michèle

    2015-12-01

    Biomonitoring of pyrethroid exposure is largely conducted but human toxicokinetics has not been fully documented. This is essential for a proper interpretation of biomonitoring data. Time profiles and toxicokinetic parameters of key biomarkers of exposure to cypermethrin in orally exposed volunteers have been documented and compared with previously available kinetic data following permethrin dosing. Six volunteers ingested 0.1 mg kg(-1) bodyweight of cypermethrin acutely. The same volunteers were exposed to permethrin earlier. Blood samples were taken over 72 h after treatment and complete timed urine voids were collected over 84 h postdosing. Cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acids (trans- and cis-DCCA) and 3-phenoxybenzoic acid (3-PBA) metabolites, common to both cypermethrin and permethrin, were quantified. Blood and urinary time courses of all three metabolites were similar following cypermethrin and permethrin exposure. Plasma levels of metabolites reached peak values on average ≈ 5-7 h post-dosing; the elimination phase showed mean apparent half-lives (t½ ) for trans-DCCA, cis-DCCA and 3-PBA of 5.1, 6.9 and 9.2 h, respectively, following cypermethrin treatment as compared to 7.1, 6.2 and 6.5 h after permethrin dosing. Corresponding mean values obtained from urinary rate time courses were peak values at ≈ 9 h post-dosing and apparent elimination t½ of 6.3, 6.4 and 6.4 h for trans-DCCA, cis-DCCA and 3-PBA, respectively, following cypermethrin treatment as compared to 5.4, 4.5 and 5.7 h after permethrin dosing. These data confirm that the kinetics of cypermethrin is similar to that of permethrin in humans and that their common biomarkers of exposure may be used for an overall assessment of exposure.

  3. Residential exposure to electromagnetic fields and childhood leukaemia: a meta-analysis.

    PubMed Central

    Angelillo, I. F.; Villari, P.

    1999-01-01

    Although individual epidemiological investigations have suggested associations between residential exposure to electromagnetic fields (EMFs) and childhood leukaemia, overall the findings have been inconclusive. Several of these studies do, however, lend themselves to application of the meta-analysis technique. For this purpose we carried out searches using MEDLINE and other sources, and 14 case-control studies and one cohort study were identified and evaluated for epidemiological quality and included in the meta-analysis. Relative risk estimates were extracted from each of the studies and pooled. Separate meta-analyses were performed on the basis of the assessed EMF exposure (wiring configuration codes, distance to power distribution equipment, spot and 24-h measures of magnetic field strength (magnetic flux density) and calculated magnetic field). The meta-analysis based on wiring configuration codes yielded a pooled relative risk estimate of 1.46 (95% confidence interval (CI) = 1.05-2.04, P = 0.024) and for that for exposure to 24-h measurements of magnetic fields, 1.59 (95% CI = 1.14-2.22, P = 0.006), indicating a potential effect of residential EMF exposure on childhood leukaemia. In most cases, lower risk estimates were obtained by pooling high-quality studies than pooling low-quality studies. There appears to be a clear trend for more recent studies to be of higher quality. Enough evidence exists to conclude that dismissing concerns about residential EMFs and childhood leukaemia is unwarranted. Additional high-quality epidemiological studies incorporating comparable measures for both exposure and outcomes are, however, needed to confirm these findings and, should they prove to be true, the case options for minimizing exposure should be thoroughly investigated to provide definitive answers for policy-makers. PMID:10612886

  4. Wellness Model of Supervision: A Comparative Analysis

    ERIC Educational Resources Information Center

    Lenz, A. Stephen; Sangganjanavanich, Varunee Faii; Balkin, Richard S.; Oliver, Marvarene; Smith, Robert L.

    2012-01-01

    This quasi-experimental study compared the effectiveness of the Wellness Model of Supervision (WELMS; Lenz & Smith, 2010) with alternative supervision models for developing wellness constructs, total personal wellness, and helping skills among counselors-in-training. Participants were 32 master's-level counseling students completing their…

  5. Comparative Analysis of Monographic Collections in Nursing.

    ERIC Educational Resources Information Center

    Bowden, Virginia M.; And Others

    The results of a project comparing the nursing monograph collections of academic health science center libraries in the Southwest are reported. Records for nursing monographs from the TALON (South Central Regional Medical Library Program) Union Catalog of Monographs from 1977-1983 were analyzed to reveal the distribution by year, publisher, and…

  6. Comparative Naval Architecture Analysis of Diesel Submarines

    DTIC Science & Technology

    2005-06-01

    mission, cost, or other factors affect the architecture? This study examines and compares the naval architecture of selected diesel submarines from...79 A ppendix E : Subm arine Shape Factors ................................................................................... 90 5 List of...country. Do factors such as mission, cost, or tradition 10 affect submarine naval architecture? An in depth comparison is performed of six diesel

  7. Comparative Lifecycle Energy Analysis: Theory and Practice.

    ERIC Educational Resources Information Center

    Morris, Jeffrey; Canzoneri, Diana

    1992-01-01

    Explores the position that more energy is conserved through recycling secondary materials than is generated from municipal solid waste incineration. Discusses one component of a lifecycle analysis--a comparison of energy requirements for manufacturing competing products. Includes methodological issues, energy cost estimates, and difficulties…

  8. Comparative molecular analysis of endoevaporitic microbial communities.

    PubMed

    Sahl, Jason W; Pace, Norman R; Spear, John R

    2008-10-01

    A phylogenetic comparison of microbial communities in hypersaline evaporites was conducted on crusts from Guerrero Negro, Mexico, and Lindsey Lake, New Mexico, using culture-independent rRNA gene sequence analysis. Many sequences were shared between evaporites, which suggests that similar environments select for specific microbial lineages from a global metacommunity.

  9. Occupational COPD and job exposure matrices: a systematic review and meta-analysis

    PubMed Central

    Sadhra, Steven; Kurmi, Om P; Sadhra, Sandeep S; Lam, Kin Bong Hubert; Ayres, Jon G

    2017-01-01

    Background The association between occupational exposure and COPD reported previously has mostly been derived from studies relying on self-reported exposure to vapors, gases, dust, or fumes (VGDF), which could be subjective and prone to biases. The aim of this study was to assess the strength of association between exposure and COPD from studies that derived exposure by job exposure matrices (JEMs). Methods A systematic search of JEM-based occupational COPD studies published between 1980 and 2015 was conducted in PubMed and EMBASE, followed by meta-analysis. Meta-analysis was performed using a random-effects model, with results presented as a pooled effect estimate with 95% confidence intervals (CIs). The quality of study (risk of bias and confounding) was assessed by 13 RTI questionnaires. Heterogeneity between studies and its possible sources were assessed by Egger test and meta-regression, respectively. Results In all, 61 studies were identified and 29 were included in the meta-analysis. Based on JEM-based studies, there was 22% (pooled odds ratio =1.22; 95% CI 1.18–1.27) increased risk of COPD among those exposed to airborne pollutants arising from occupation. Comparatively, higher risk estimates were obtained for general populations JEMs (based on expert consensus) than workplace-based JEM were derived using measured exposure data (1.26; 1.20–1.33 vs 1.14; 1.10–1.19). Higher risk estimates were also obtained for self-reported exposure to VGDF than JEMs-based exposure to VGDF (1.91; 1.72–2.13 vs 1.10; 1.06–1.24). Dusts, particularly biological dusts (1.33; 1.17–1.51), had the highest risk estimates for COPD. Although the majority of occupational COPD studies focus on dusty environments, no difference in risk estimates was found for the common forms of occupational airborne pollutants. Conclusion Our findings highlight the need to interpret previous studies with caution as self-reported exposure to VGDF may have overestimated the risk of occupational

  10. Mapping of radio frequency electromagnetic field exposure levels in outdoor environment and comparing with reference levels for general public health.

    PubMed

    Cansiz, Mustafa; Abbasov, Teymuraz; Kurt, M Bahattin; Celik, A Recai

    2016-11-02

    In this study, radio frequency electromagnetic field exposure levels were measured on the main streets in the city center of Diyarbakır, Turkey. Measured electric field levels were plotted on satellite imagery of Diyarbakır and were compared with exposure guidelines published by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Exposure measurements were performed in dense urban, urban and suburban areas each day for 7 consecutive days. The measurement system consisted of high precision and portable spectrum analyzer, three-axis electric field antenna, connection cable and a laptop which was used to record the measurement samples as a data logger. The highest exposure levels were detected for two places, which are called Diclekent and Batıkent. It was observed that the highest instantaneous electric field strength value for Batıkent was 7.18 V/m and for Diclekent was 5.81 V/m. It was statistically determined that the main contributor band to the total exposure levels was Universal Mobile Telecommunications System band. Finally, it was concluded that all measured exposure levels were lower than the reference levels recommended by ICNIRP for general public health.Journal of Exposure Science and Environmental Epidemiology advance online publication, 2 November 2016; doi:10.1038/jes.2016.64.

  11. Comparative pharmacokinetic study of the role of gender and developmental differences in occupational and environmental exposure to benzene. Master's thesis

    SciTech Connect

    Brown, E.A.

    1994-09-01

    The purpose of this study is two-fold. First, it shows that physiological differences between men and women result in gender-specific exposures with respect to benzene. Second, it assesses the potential for a lactating woman's occupational and personal benzene exposure to impact a nursing infant's exposure, highlighting the possibility of subjecting an infant to the effects of industrial chemicals via breast feeding. This study employs physiologically based pharmacokinetic (PBPK) modeling to investigate the influence of physiological parameters and to evaluate the ability of inhaled benzene to transfer from mother to infant through breastmilk. The models are run through scenarios that simulate occupational, smoking, and background exposures. The gender comparison is facilitated by a sensitivity analysis. The blood/air partition coefficient and maximum velocity of metabolism were found to substantially impact model output. These values were both higher in women and caused an increase in the percentage of benzene metabolized in all of the exposure scenarios. The study of lactating women and infants is essentially theoretical. There is evidence that over 65% of an infant's benzene exposure can be attributed to contaminated breastmilk. A large portion of the ingested exposure can be eliminated by adjusting the mother's working or nursing schedule. Benzene, Physiologically based pharmacokinetics, PBPK.

  12. Occupational Radiation Exposure Analysis of US ITER DCLL TBM

    SciTech Connect

    Merrill, Brad J; Cadwallader, Lee C; Dagher, Mohamad

    2007-08-01

    This report documents an Occupational Radiation Exposure (ORE) analysis that was performed for the US International Thermonuclear Experimental Reactor (ITER) Dual Coolant Lead Lithium (DCLL) Test Blanket Module (TBM). This analysis was performed with the QADMOD dose code for anticipated maintenance activities for this TBM concept and its ancillary systems. The QADMOD code was used to model the PbLi cooling loop of this TBM concept by specifying gamma ray source terms that simulated radioactive material within the piping, valves, heat exchanger, permeator, pump, drain tank, and cold trap of this cooling system. Estimates of the maintenance tasks that will have to be performed and the time required to perform these tasks where developed based on either expert opinion or on industrial maintenance experience for similar technologies. This report details the modeling activity and the calculated doses for the maintenance activities envisioned for the US DCLL TBM.

  13. Comparative Analysis of Treatment Costs in EUROHOPE.

    PubMed

    Iversen, Tor; Aas, Eline; Rosenqvist, Gunnar; Häkkinen, Unto

    2015-12-01

    This study examines the challenges of estimating risk-adjusted treatment costs in international comparative research, specifically in the European Health Care Outcomes, Performance, and Efficiency (EuroHOPE) project. We describe the diverse format of resource data and challenges of converting these data into resource use indicators that allow meaningful cross-country comparisons. The three cost indicators developed in EuroHOPE are then described, discussed, and applied. We compare the risk-adjusted mean treatment costs of acute myocardial infarction for four of the seven countries in the EuroHOPE project, namely, Finland, Hungary, Norway, and Sweden. The outcome of the comparison depends on the time perspective as well as on the particular resource use indicator. We argue that these complementary indicators add to our understanding of the variation in resource use across countries.

  14. A Comparative Analysis of Reinforcement Learning Methods

    DTIC Science & Technology

    1991-10-01

    reinforcement learning for both programming and adapting situated agents. In the first part of the paper we discuss two specific reinforcement learning algorithms: Q-learning and the Bucket Brigade. We introduce a special case of the Bucket Brigade, and analyze and compare its performance to Q-learning in a number of experiments. The second part of the paper discusses the key problems of reinforcement learning : time and space complexity, input generalization, sensitivity to parameter values, and selection of the reinforcement

  15. Multiattribute Decision Modeling Techniques: A Comparative Analysis

    DTIC Science & Technology

    1988-08-01

    Rating Technique (SMART) as a direct response to Raiffa’s (1969) article on multiattribute utility theory , which Edwards found extremcy stimulating but...approaches such as multiattribute utility /value assessment and hierarchical analysis and have applied these techniques to a number of non-military... multiattributed ) outcomes O(l)...O(k), and if the utility function is denoted by u and the probabilities of the k events are p(l)...p(k), then the

  16. Comparative analysis of plant oil based fuels

    SciTech Connect

    Ziejewski, M.; Goettler, H.J.; Haines, H.; Huong, C.

    1995-12-31

    This paper presents the evaluation results from the analysis of different blends of fuels using the 13-mode standard SAE testing method. Six high oleic safflower oil blends, six ester blends, six high oleic sunflower oil blends, and six sunflower oil blends were used in this portion of the investigation. Additionally, the results from the repeated 13-mode tests for all the 25/75% mixtures with a complete diesel fuel test before and after each alternative fuel are presented.

  17. Assessment of General Public Exposure to LTE signals compared to other Cellular Networks Present in Thessaloniki, Greece.

    PubMed

    Gkonis, Fotios; Boursianis, Achilles; Samaras, Theodoros

    2016-12-15

    To assess general public exposure to electromagnetic fields from Long Term Evolution (LTE) base stations, measurements at 10 sites in Thessaloniki, Greece were performed. Results are compared with other mobile cellular networks currently in use. All exposure values satisfy the guidelines for general public exposure of the International Commission on Non-Ionizing Radiation Protection (ICNIRP), as well as the reference levels by the Greek legislation at all sites. LTE electric field measurements were recorded up to 0.645 V/m. By applying the ICNIRP guidelines, the exposure ratio for all LTE signals is between 2.9 × 10(-5) and 2.8 × 10(-2) From the measurements results it is concluded that the average and maximum power density contribution of LTE downlink signals to the overall cellular networks signals are 7.8% and 36.7%, respectively.

  18. Comparative changes in rat liver cytosolic proteins by mirex, diethylnitrosamine, and dimethylnitrosamine exposure

    SciTech Connect

    Timchalk, C.; Charles, A.K.; Abraham, R.

    1985-11-01

    Using a newborn rat model for carcinogenesis, changes in liver cytosolic proteins at three stages of tumorigenesis, on Days 21, 97, and 120, by mirex (dodecachloropentacyclo-1,3,4-metheno-2H-cyclobuta(cd)pentalene), and diethyl- and dimethylnitrosamines (DEN and DMN) were studied. Following multiple exposure to the hepatocarcinogens, groups of weanling rats were given dietary phenobarbital (PB) up to 120 days. SDS-PAGE separation of cytosolic proteins showed that at 21 days, prior to PB, two proteins of 26K and 23K mol wt were significantly induced by mirex and DMN while a high mol wt 63K protein was induced only by DEN and DMN. During the period of PB treatment up to 97 days, these proteins were well sustained at a higher level. A marked increase in 21K protein band was also observed at this point. In tumor tissues obtained from DEN and DMN rats continued on PB diet for 120 days, the high level of 63K protein was seen only in DEN and not in DMN tumor. The tumors also showed a significant reduction in 25K protein compared to 21- and 97-day groups. The presence of even lower mol wt proteins of 14-21K was seen in tumors. The early detection and further characterization of these low mol wt proteins may provide clues as to whether they are preneoplastic markers or oncogene products as speculated by other investigators. Moreover, certain similarities in the induction of cytosolic proteins by epigenetic and genotoxic carcinogens raise more interesting questions regarding the mechanisms of action of these distinct classes of carcinogens.

  19. Comparative Analysis of GOCI Ocean Color Products

    PubMed Central

    Amin, Ruhul; Lewis, Mark David; Lawson, Adam; Gould, Richard W.; Martinolich, Paul; Li, Rong-Rong; Ladner, Sherwin; Gallegos, Sonia

    2015-01-01

    The Geostationary Ocean Color Imager (GOCI) is the first geostationary ocean color sensor in orbit that provides bio-optical properties from coastal and open waters around the Korean Peninsula at unprecedented temporal resolution. In this study, we compare the normalized water-leaving radiance (nLw) products generated by the Naval Research Laboratory Automated Processing System (APS) with those produced by the stand-alone software package, the GOCI Data Processing System (GDPS), developed by the Korean Ocean Research & Development Institute (KORDI). Both results are then compared to the nLw measured by the above water radiometer at the Ieodo site. This above-water radiometer is part of the Aerosol Robotic NETwork (AeroNET). The results indicate that the APS and GDPS processed nLw correlates well within the same image slot where the coefficient of determination (r2) is higher than 0.84 for all the bands from 412 nm to 745 nm. The agreement between APS and the AeroNET data is higher when compared to the GDPS results. The Root-Mean-Squared-Error (RMSE) between AeroNET and APS data ranges from 0.24 [mW/(cm2srμm)] at 555 nm to 0.52 [mW/(cm2srμm)] at 412 nm while RMSE between AeroNET and GDPS data ranges from 0.47 [mW/(cm2srμm)] at 443 nm to 0.69 [mW/(cm2srμm)] at 490 nm. PMID:26473861

  20. [Amaranth flour: characteristics, comparative analysis, application possibilities].

    PubMed

    Zharkov, I M; Miroshnichenko, L A; Zviagin, A A; Bavykina, I A

    2014-01-01

    Amaranth flour--a product of amaranth seeds processing--is a valuable industrial raw material that has an unique chemical composition and may be used for nutrition of people suffering from intolerance to traditional cereals protein, including celiac disease patients. The research aim was to study the composition of amaranth flour of two types compared with semolina which is traditionally used for nutrition by Russian population, as well as to compare the composition of milk amaranth flour porridge with milk semolina porridge. The composition of amaranth whole-ground flour and amaranth flour of premium grade processed from amaranth seeds grown in Voronezh region has been researched. It is to be noted that protein content in amaranth flour was 10.8-24.3% higher than in semolina, and its biological value and NPU-coefficient were higher by 22.65 and 46.51% respectively; lysine score in amaranth flour protein of premium grade came up to 107.54%, and in semolina protein only 40.95%. The level of digestible carbohydrates, including starch, was lower in amaranth flour than in semolina by 2.79-12.85 and 4.76-15.85% respectively, while fiber content was 15.5-30 fold higher. Fat content in amaranth flour of premium grade was 2,4 fold lower than in whole-ground amaranth flour but it was 45% higher than in semolina. The main advantage of amaranth flour protein compared to wheat protein is the predominance of albumins and globulins and a minimal content of prolamines and alpha-gliadin complete absence. The specifics of chemical composition allow the amaranth flour to be recommended for being included into nutrition of both healthy children and adults and also celiac disease patients.

  1. Comparative analysis of condensation models within DSMC

    SciTech Connect

    Bykov, Nikolay Y.; Gorbachev, Yuriy E.

    2014-12-09

    Two condensation process modeling approaches within DSMC methodology are compared. The first is based on the modified nucleation theory which correctly describes small clusters and the second on the kinetic theory and considers not only supercritical clusters, but clusters of all sizes including dimers. The relaxation of the size distribution function is calculated for the spatially homogeneous cases, where the monomer parameters are kept constant. As an example the vapour of Cu atoms is considered and importance of taking into account of the internal energies of clusters is shown. Peculiarities of the classical and kinetic approaches are discussed herein.

  2. Comparative quantitative proteomics unveils putative mechanisms involved into mercury toxicity and tolerance in Tigriopus japonicus under multigenerational exposure scenario.

    PubMed

    Xu, Xiaoqun; Shi, Lin; Wang, Minghua

    2016-11-01

    In our earlier work, Tigriopus japonicus were subjected to different mercuric chloride treatments (0-50 μg/L in the seawater) for five generations (F0-F4), and they were subsequently resumed under clean environments for one generation, i.e., F5. Accumulative effects were hypothesized to participate in mercury (Hg) multigenerational toxicity, however phenotypic plasticity could be responsible for metal resistance in this copepod against the long term exposure. Here, we specifically investigated the proteome profiles in the F0, F2, and F5 copepods of the control and 50 μg/L metal treatment, respectively, so as to elucidate the action mechanisms for Hg toxicity/tolerance in T. japonicus under the long term exposure. Functional enrichment analysis showed that a quite different proteomic response was observed in F5 compared with F0 and F2. Namely, the vast majority of enrichments were correlated with the down-regulated proteins in F0 and F2, whereas the enrichments for F5 were mostly attributable to the up-regulated proteins, suggesting that different mechanisms are responsible for Hg toxicity and tolerance (i.e., phenotypic plasticity). Hg toxicity prohibited many proteins in F0 and F2 which are related to several critical processes/pathways, e.g., protein translation, macromolecule metabolic process, DNA replication, cell cycle, cuticle organization, vitellogenesis, etc. In F5, many up-regulated proteins were enriched into compensatory systems, such as carbohydrate metabolism, myosin reorganizations, and stress-related defense pathway. Notably, glycolysis (an oxygen-independent pathway) was enhanced for energy allocation into metal detoxification and tolerance. Taken together, proteomics provides novel mechanistic insights into phenotypic plasticity used by T. japonicus when challenged with cumulative effects due to Hg multigenerational toxicity.

  3. Respirable quartz dust exposure and airway obstruction: a systematic review and meta-analysis.

    PubMed

    Brüske, Irene; Thiering, Elisabeth; Heinrich, Joachim; Huster, Katharina M; Nowak, Dennis

    2014-08-01

    Studies on exposure to respirable quartz dust at the workplace and the development of chronic obstructive pulmonary disease (COPD) were selected into a systematic review and meta-analysed to obtain an overall estimate of forced expiratory volume in 1 s (FEV1) and FEV1/forced vital capacity (FVC) reduction. PubMed and Embase were searched from 1970 to 2010. In total, 257 cross-sectional and longitudinal studies were identified that reported on inorganic dust exposure and had available lung function data. Of the 55 publications which met our inclusion criteria, 11 reported on associations with occupational exposure to respirable quartz dust. The combined average effect estimate of respirable quartz dust on spirometric parameters was obtained using a random effects model meta-analysis. Between-study heterogeneity was assessed via the I(2) statistic. Most studies found a significant negative association of FEV1 and FEV1/FVC related to increasing exposure to crystalline quartz at the workplace. One study found an effect only for smokers, and one did not observe such an effect at all. The meta-analysis of cross-sectional studies showed that the mean ratio FEV1 to FVC was reduced and FEV1 of workers exposed to respirable quartz dust was 4.6% less than predicted compared with workers with no/low exposure. Both results showed a statistically significant difference. Occupational exposure to respirable quartz dust was associated with a statistically significant decrease in FEV1 and FEV1/FVC, revealing airway obstruction consistent with COPD.

  4. Comparative analysis of Goodwin's business cycle models

    NASA Astrophysics Data System (ADS)

    Antonova, A. O.; Reznik, S.; Todorov, M. D.

    2016-10-01

    We compare the behavior of solutions of Goodwin's business cycle equation in the form of neutral delay differential equation with fixed delay (NDDE model) and in the form of the differential equations of 3rd, 4th and 5th orders (ODE model's). Such ODE model's (Taylor series expansion of NDDE in powers of θ) are proposed in N. Dharmaraj and K. Vela Velupillai [6] for investigation of the short periodic sawthooth oscillations in NDDE. We show that the ODE's of 3rd, 4th and 5th order may approximate the asymptotic behavior of only main Goodwin's mode, but not the sawthooth modes. If the order of the Taylor series expansion exceeds 5, then the approximate ODE becomes unstable independently of time lag θ.

  5. Comparative LIBS Analysis Of Calcified Tissues

    SciTech Connect

    Abdel-Salam, Z. A.; Harith, M. A.

    2008-09-23

    Signal enhancement, limits of detection, and relevance to environmental concentration for element in calcified tissues using LIBS with single and double laser pulses will be presented. These measurements were performed on three calcified tissues representing different matrices, namely enamel of human teeth, shells and eggshells. This method depends on the role of the laser induced shock wave on the ionization rate of the ablated target material atoms. The effect of the laser single and double pulse on the ionic to atomic ratio of calcium and magnesium spectral emission lines, CaII/CaI and MgII/MgI, will be presented and compared with the previous results and its relevance to the target material hardness. The results show that in case of single pulse the intensity ratios in calcium are higher than the double pulse while there is no appreciable difference between both in case of magnesium.

  6. Comparative analysis of Debrecen sunspot catalogues

    NASA Astrophysics Data System (ADS)

    Győri, L.; Ludmány, A.; Baranyi, T.

    2017-02-01

    Sunspot area data are important for studying solar activity and its long-term variations. At the Debrecen Heliophysical Observatory, we compiled three sunspot catalogues: the Debrecen Photoheliographic Data (DPD), the SDO/HMI Debrecen Data (HMIDD) and the SOHO/MDI Debrecen Data. For comparison, we also compiled an additional sunspot catalogue, the Greenwich Photoheliographic Data, from the digitized Royal Greenwich Observatory images for 1974-76. By comparing these catalogues when they overlap in time, we can investigate how various factors influence the measured area of sunspots, and, in addition, we can derive area cross-calibration factors for these catalogues. The main findings are as follows. Poorer seeing increases the individual corrected spot areas and decreases the number of small spots. Interestingly, the net result of these two effects for the total corrected spot area is zero. DPD daily total corrected sunspot areas are 5 per cent smaller than the HMIDD ones. Revised DPD daily total corrected umbra areas are 9 per cent smaller than those of HMIDD. The Greenwich photoheliographic areas are only a few per cent smaller than DPD areas. A 0.2° difference between the north directions of the DPD and MDI images is found. This value is nearly the same as was found (0.22°) by us in a previous paper comparing HMI and MDI images. The area measurement practice (spots smaller than 10 mh were not directly measured but an area of 2 mh was assigned to each) of the Solar Observing Optical Network cannot explain the large area deficit of the Solar Observing Optical Network.

  7. Comparative analysis of cystatin superfamily in platyhelminths.

    PubMed

    Guo, Aijiang

    2015-01-01

    The cystatin superfamily is comprised of cysteine proteinase inhibitors and encompasses at least 3 subfamilies: stefins, cystatins and kininogens. In this study, the platyhelminth cystatin superfamily was identified and grouped into stefin and cystatin subfamilies. The conserved domain of stefins (G, QxVxG) was observed in all members of platyhelminth stefins. The three characteristics of cystatins, the cystatin-like domain (G, QxVxG, PW), a signal peptide, and one or two conserved disulfide bonds, were observed in platyhelminths, with the exception of cestodes, which lacked the conserved disulfide bond. However, it is noteworthy that cestode cystatins had two tandem repeated domains, although the second tandem repeated domain did not contain a cystatin-like domain, which has not been previously reported. Tertiary structure analysis of Taenia solium cystatin, one of the cestode cystatins, demonstrated that the N-terminus of T. solium cystatin formed a five turn α-helix, a five stranded β-pleated sheet and a hydrophobic edge, similar to the structure of chicken cystatin. Although no conserved disulfide bond was found in T. solium cystatin, the models of T. solium cystatin and chicken cystatin corresponded at the site of the first disulfide bridge of the chicken cystatin. However, the two models were not similar regarding the location of the second disulfide bridge of chicken cystatin. These results showed that T. solium cystatin and chicken cystatin had similarities and differences, suggesting that the biochemistry of T. solium cystatin could be similar to chicken cystatin in its inhibitory function and that it may have further functional roles. The same results were obtained for other cestode cystatins. Phylogenetic analysis showed that cestode cystatins constituted an independent clade and implied that cestode cystatins should be considered to have formed a new clade during evolution.

  8. Airborne asbestos exposures associated with gasket and packing replacement: a simulation study and meta-analysis.

    PubMed

    Madl, Amy K; Hollins, Dana M; Devlin, Kathryn D; Donovan, Ellen P; Dopart, Pamela J; Scott, Paul K; Perez, Angela L

    2014-08-01

    Exposures to airborne asbestos during the removal and installation of internal gaskets and packing associated with a valve overhaul were characterized and compared to published data according to different variables (e.g., product, equipment, task, tool, setting, duration). Personal breathing zone and area samples were collected during twelve events simulating gasket and packing replacement, clean-up and clothing handling. These samples were analyzed using PCM and TEM methods and PCM-equivalent (PCME) airborne asbestos concentrations were calculated. A meta-analysis was performed to compare these data with airborne asbestos concentrations measured in other studies involving gaskets and packing. Short-term mechanic and assistant airborne asbestos concentrations during valve work averaged 0.013f/cc and 0.008f/cc (PCME), respectively. Area samples averaged 0.008f/cc, 0.005f/cc, and 0.003f/cc (PCME) for center, bystander, and remote background, respectively. Assuming a tradesman conservatively performs 1-3 gasket and/or packing replacements daily, an average 8-h TWA was estimated to be 0.002-0.010f/cc (PCME). Combining these results in a meta-analysis of the published exposure data showed that the majority of airborne asbestos exposures during work with gaskets and packing fall within a consistent and low range. Significant differences in airborne concentrations were observed between power versus manual tools and removal versus installation tasks. Airborne asbestos concentrations resulting from gasket and packing work during a valve overhaul are consistent with historical exposure data on replacement of asbestos-containing gasket and packing materials involving multiple variables and, in nearly all plausible scenarios, result in average airborne asbestos concentrations below contemporaneous occupational exposure limits for asbestos.

  9. Recognizing chemicals in patents: a comparative analysis.

    PubMed

    Habibi, Maryam; Wiegandt, David Luis; Schmedding, Florian; Leser, Ulf

    2016-01-01

    Recently, methods for Chemical Named Entity Recognition (NER) have gained substantial interest, driven by the need for automatically analyzing todays ever growing collections of biomedical text. Chemical NER for patents is particularly essential due to the high economic importance of pharmaceutical findings. However, NER on patents has essentially been neglected by the research community for long, mostly because of the lack of enough annotated corpora. A recent international competition specifically targeted this task, but evaluated tools only on gold standard patent abstracts instead of full patents; furthermore, results from such competitions are often difficult to extrapolate to real-life settings due to the relatively high homogeneity of training and test data. Here, we evaluate the two state-of-the-art chemical NER tools, tmChem and ChemSpot, on four different annotated patent corpora, two of which consist of full texts. We study the overall performance of the tools, compare their results at the instance level, report on high-recall and high-precision ensembles, and perform cross-corpus and intra-corpus evaluations. Our findings indicate that full patents are considerably harder to analyze than patent abstracts and clearly confirm the common wisdom that using the same text genre (patent vs. scientific) and text type (abstract vs. full text) for training and testing is a pre-requisite for achieving high quality text mining results.

  10. Comparative analysis of de novo transcriptome assembly.

    PubMed

    Clarke, Kaitlin; Yang, Yi; Marsh, Ronald; Xie, Linglin; Zhang, Ke K

    2013-02-01

    The fast development of next-generation sequencing technology presents a major computational challenge for data processing and analysis. A fast algorithm, de Bruijn graph has been successfully used for genome DNA de novo assembly; nevertheless, its performance for transcriptome assembly is unclear. In this study, we used both simulated and real RNA-Seq data, from either artificial RNA templates or human transcripts, to evaluate five de novo assemblers, ABySS, Mira, Trinity, Velvet and Oases. Of these assemblers, ABySS, Trinity, Velvet and Oases are all based on de Bruijn graph, and Mira uses an overlap graph algorithm. Various numbers of RNA short reads were selected from the External RNA Control Consortium (ERCC) data and human chromosome 22. A number of statistics were then calculated for the resulting contigs from each assembler. Each experiment was repeated multiple times to obtain the mean statistics and standard error estimate. Trinity had relative good performance for both ERCC and human data, but it may not consistently generate full length transcripts. ABySS was the fastest method but its assembly quality was low. Mira gave a good rate for mapping its contigs onto human chromosome 22, but its computational speed is not satisfactory. Our results suggest that transcript assembly remains a challenge problem for bioinformatics society. Therefore, a novel assembler is in need for assembling transcriptome data generated by next generation sequencing technique.

  11. Community detection algorithms: a comparative analysis.

    PubMed

    Lancichinetti, Andrea; Fortunato, Santo

    2009-11-01

    Uncovering the community structure exhibited by real networks is a crucial step toward an understanding of complex systems that goes beyond the local organization of their constituents. Many algorithms have been proposed so far, but none of them has been subjected to strict tests to evaluate their performance. Most of the sporadic tests performed so far involved small networks with known community structure and/or artificial graphs with a simplified structure, which is very uncommon in real systems. Here we test several methods against a recently introduced class of benchmark graphs, with heterogeneous distributions of degree and community size. The methods are also tested against the benchmark by Girvan and Newman [Proc. Natl. Acad. Sci. U.S.A. 99, 7821 (2002)] and on random graphs. As a result of our analysis, three recent algorithms introduced by Rosvall and Bergstrom [Proc. Natl. Acad. Sci. U.S.A. 104, 7327 (2007); Proc. Natl. Acad. Sci. U.S.A. 105, 1118 (2008)], Blondel [J. Stat. Mech.: Theory Exp. (2008), P10008], and Ronhovde and Nussinov [Phys. Rev. E 80, 016109 (2009)] have an excellent performance, with the additional advantage of low computational complexity, which enables one to analyze large systems.

  12. Breastfeeding policy: a globally comparative analysis

    PubMed Central

    Raub, Amy; Earle, Alison

    2013-01-01

    Abstract Objective To explore the extent to which national policies guaranteeing breastfeeding breaks to working women may facilitate breastfeeding. Methods An analysis was conducted of the number of countries that guarantee breastfeeding breaks, the daily number of hours guaranteed, and the duration of guarantees. To obtain current, detailed information on national policies, original legislation as well as secondary sources on 182 of the 193 Member States of the United Nations were examined. Regression analyses were conducted to test the association between national policy and rates of exclusive breastfeeding while controlling for national income level, level of urbanization, female percentage of the labour force and female literacy rate. Findings Breastfeeding breaks with pay are guaranteed in 130 countries (71%) and unpaid breaks are guaranteed in seven (4%). No policy on breastfeeding breaks exists in 45 countries (25%). In multivariate models, the guarantee of paid breastfeeding breaks for at least 6 months was associated with an increase of 8.86 percentage points in the rate of exclusive breastfeeding (P < 0.05). Conclusion A greater percentage of women practise exclusive breastfeeding in countries where laws guarantee breastfeeding breaks at work. If these findings are confirmed in longitudinal studies, health outcomes could be improved by passing legislation on breastfeeding breaks in countries that do not yet ensure the right to breastfeed. PMID:24052676

  13. Hair analysis for the biomonitoring of pesticide exposure: comparison with blood and urine in a rat model.

    PubMed

    Appenzeller, Brice M R; Hardy, Emilie M; Grova, Nathalie; Chata, Caroline; Faÿs, François; Briand, Olivier; Schroeder, Henri; Duca, Radu-Corneliu

    2016-12-23

    Urine and plasma have been used to date for the biomonitoring of exposure to pollutants and are still the preferred fluids for this purpose; however, these fluids mainly provide information on the short term and may present a high level of variability regarding pesticide concentrations, especially for nonpersistent compounds. Hair analysis may provide information about chronic exposure that is averaged over several months; therefore, this method has been proposed as an alternative to solely relying on these fluids. Although the possibility of detecting pesticides in hair has been demonstrated over the past few years, the unknown linkage between exposure and pesticides concentration in hair has limited the recognition of this matrix as a relevant tool for assessing human exposure. Based on a rat model in which there was controlled exposure to a mixture of pesticides composed of lindane, β-hexachlorocyclohexane, β-endosulfan, p,p'-DDT, p,p'-DDE, dieldrin, pentachlorophenol, diazinon, chlorpyrifos, cyhalothrin, permethrin, cypermethrin, propiconazole, fipronil, oxadiazon, diflufenican, trifluralin, carbofuran, and propoxur, the current work demonstrates the association between exposure intensity and resulting pesticide concentration in hair. We also compared the results obtained from a hair analysis to urine and plasma collected from the same rats. Hair, blood, and urine were collected from rats submitted to 90-day exposure by gavage to the aforementioned mixture of common pesticides at different levels. We observed a linear relationship between exposure intensity and the concentration of pesticides in the rats' hair (R Pearson 0.453-0.978, p < 0.01). A comparison with results from urine and plasma samples demonstrated the relevance of hair analysis and, for many chemicals, its superiority over using fluids for differentiating animals from different groups and for re-attributing animals to their correct groups of exposure based on pesticide concentrations in the

  14. TISSUE CONCENTRATION OF PCBS IN ANIMAL EXPERIMENTS AS COMPARED WITH THOSE IN HUMANS WITH BACKGROUND-LEVEL EXPOSURE

    EPA Science Inventory

    TISSUE CONCENTRATION OF PCBS IN ANIMAL EXPERIMENTS AS COMPARED WITH THOSE IN HUMANS WITH BACKGROUND-LEVEL EXPOSURE. M J DeVito1 and M P Longnecker2. 1NHEERL, ORD, USEPA; Research Triangle Park, NC, USA; 2Epidemiology
    Branch, NIEHS, Research Triangle Park, NC, USA.

    To ...

  15. Human performance analysis of industrial radiography radiation exposure events

    SciTech Connect

    Reece, W.J.; Hill, S.G.

    1995-12-01

    A set of radiation overexposure event reports were reviewed as part of a program to examine human performance in industrial radiography for the US Nuclear Regulatory Commission. Incident records for a seven year period were retrieved from an event database. Ninety-five exposure events were initially categorized and sorted for further analysis. Descriptive models were applied to a subset of severe overexposure events. Modeling included: (1) operational sequence tables to outline the key human actions and interactions with equipment, (2) human reliability event trees, (3) an application of an information processing failures model, and (4) an extrapolated use of the error influences and effects diagram. Results of the modeling analyses provided insights into the industrial radiography task and suggested areas for further action and study to decrease overexposures.

  16. ANALYSIS OF DISCRIMINATING FACTORS IN HUMAN ACTIVITIES THAT AFFECT EXPOSURE

    EPA Science Inventory

    Accurately modeling exposure to particulate matter (PM) and other pollutants ultimately involves the utilization of human location-activity databases to assist in understanding the potential variability of microenvironmental exposures. This paper critically considers and stati...

  17. THE ROLE OF EXPOSURE ANALYSIS IN HUMAN HEALTH RISK ASSESSMENT

    EPA Science Inventory

    This presentation will cover the basic methodologies used for assessing human exposures to environmental pollutants, and some of the scientific challenges involved in conducting exposure and risk assessments in support of regulatory evaluations.

  18. The effect of randomised exposure to different types of natural outdoor environments compared to exposure to an urban environment on people with indications of psychological distress in Catalonia

    PubMed Central

    Gidlow, Christopher J.; Martínez, David; de Bont, Jeroen; Carrasco-Turigas, Glòria; Martínez-Íñiguez, Tania; Hurst, Gemma; Masterson, Daniel; Donaire-Gonzalez, David; Seto, Edmund; Jones, Marc V.; Nieuwenhuijsen, Mark J.

    2017-01-01

    Introduction Experimental studies have reported associations between short-term exposure to natural outdoor environments (NOE) and health benefits. However, they lack insight into mechanisms, often have low external and ecological validity, and have rarely focused on people with some psycho-physiological affection. The aim of this study was to use a randomized, case-crossover design to investigate: (i) the effects of unconstrained exposure to real natural and urban environments on psycho-physiological indicators of people with indications of psychological distress, (ii) the possible differential effects of 30 and 30+180 minutes exposures, and (iii) the possible mechanisms explaining these effects. Material and methods People (n = 26) with indications of psychological distress were exposed to green (Collserola Natural Park), blue (Castelldefels beach) and urban (Eixample neighbourhood) environments in Catalonia. They were exposed to all environments in groups for a period of 30+180 minutes between October 2013 and January 2014. During the exposure period, participants were instructed to do what they would usually do in that environment. Before, during (at 30 and 30+180 minutes) and after each exposure, several psycho-physiological measures were taken: mood (measured as Total Mood Disturbance, TMD), attention capacity (measured as backwards digit-span task), stress levels (measures as salivary cortisol), systolic and diastolic blood pressure, heart rate, autonomous nervous system (assessed as heart rate variability and the indicators: low frequency power (LF), high frequency power (HF), ratio between LF and HF (LF:HF), and coefficients of component variance of LF, HF, and LF:HF). We also measured several potential mediators: air pollution, noise, physical activity, social interactions, and self-perceived restoration experience. Results When compared with responses to urban environment, we found statistically significantly lower TMD [-4.78 (-7.77, -1.79) points

  19. Comparative bactericidal exposures for selected oral bacteria using carbon dioxide laser radiation

    SciTech Connect

    Dederich, D.N.; Pickard, M.A.; Vaughn, A.S.; Tulip, J.; Zakariasen, K.L. )

    1990-01-01

    Although relatively high CO{sub 2} laser energies have been shown to sterilize root canals, the response of several bacterial strains to decreasing exposures of CO{sub 2} laser energy remains unknown. Freshly grown bacterial cells were irradiated on glass microscope coverslips. A comparison of equivalent energy exposures with differing parameters was made on the bacterial viability. No statistically significant difference was found in the energy required to kill closely related bacterial species. However, the energy density required to kill greater than 99.5% of the bacteria is less than 200 J/cm{sup 2}, much less than that shown to sterilize in a previous study.

  20. Combined analysis of job and task benzene air exposures among workers at four US refinery operations.

    PubMed

    Burns, Amanda; Shin, Jennifer Mi; Unice, Ken M; Gaffney, Shannon H; Kreider, Marisa L; Gelatt, Richard H; Panko, Julie M

    2017-03-01

    Workplace air samples analyzed for benzene at four US refineries from 1976 to 2007 were pooled into a single dataset to characterize similarities and differences between job titles, tasks and refineries, and to provide a robust dataset for exposure reconstruction. Approximately 12,000 non-task (>180 min) personal samples associated with 50 job titles and 4000 task (<180 min) samples characterizing 24 tasks were evaluated. Personal air sample data from four individual refineries were pooled based on a number of factors including (1) the consistent sampling approach used by refinery industrial hygienists over time, (2) the use of similar exposure controls, (3) the comparability of benzene content of process streams and end products, (4) the ability to assign uniform job titles and task codes across all four refineries, and (5) our analysis of variance (ANOVA) of the distribution of benzene air concentrations for select jobs/tasks across all four refineries. The jobs and tasks most frequently sampled included those with highest potential contact with refinery product streams containing benzene, which reflected the targeted sampling approach utilized by the facility industrial hygienists. Task and non-task data were analyzed to identify and account for significant differences within job-area, task-job, and task-area categories. This analysis demonstrated that in general, areas with benzene containing process streams were associated with greater benzene air concentrations compared to areas with process streams containing little to no benzene. For several job titles and tasks analyzed, there was a statistically significant decrease in benzene air concentration after 1990. This study provides a job and task-focused analysis of occupational exposure to benzene during refinery operations, and it should be useful for reconstructing refinery workers' exposures to benzene over the past 30 years.

  1. Comparative study of water ice exposures on cometary nuclei using multispectral imaging data

    NASA Astrophysics Data System (ADS)

    Oklay, N.; Sunshine, J. M.; Pajola, M.; Pommerol, A.; Vincent, J.-B.; Mottola, S.; Sierks, H.; Fornasier, S.; Barucci, M. A.; Preusker, F.; Scholten, F.; Lara, L. M.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; A'Hearn, M. F.; Bertaux, J.-L.; Bertini, I.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Davidsson, B. J. R.; Debei, S.; De Cecco, M.; Deller, J.; Fulle, M.; Gicquel, A.; Groussin, O.; Gutiérrez, P. J.; Güttler, C.; Hall, I.; Hofmann, M.; Hviid, S. F.; Ip, W.-H.; Jorda, L.; Keller, H. U.; Knollenberg, J.; Kovacs, G.; Kramm, J.-R.; Kührt, E.; Küppers, M.; Lazzarin, M.; Lin, Z.-Y.; Lopez Moreno, J. J.; Marzari, F.; Naletto, G.; Shi, X.; Thomas, N.; Tubiana, C.

    2016-11-01

    Deep Impact, EPOXI and Rosetta missions visited comets 9P/Tempel 1, 103P/Hartley 2 and 67P/Churyumov-Gerasimenko, respectively. Each of these three missions was equipped with both multispectral imagers and infrared spectrometers. Bright blue features containing water ice were detected in each of these comet nuclei. We analysed multispectral properties of enriched water ice features observed via Optical, Spectroscopic, and Infrared Remote Imaging System narrow angle camera on comet 67P in the wavelength range of 260-1000 nm and then compared with multispectral data of water ice deposits observed on comets 9P and 103P. We characterize the UV/VIS properties of water-ice-rich features observed on the nuclei of these three comets. When compared to the average surface of each comet, our analysis shows that the water ice deposits seen on comet 9P are similar to the clustered water-ice-rich features seen on comet 67P, while the water ice deposit seen on comet 103P is more akin to two large isolated water-ice-rich features seen on comet 67P. Our results indicate that the water ice deposit observed on comet 103P contains more water ice than the water-ice-rich features observed on comets 9P and 67P, proportionally to the average surface of each nucleus.

  2. The Influence of Initial Exposure on Lexical Representation: Comparing Early and Simultaneous Bilinguals

    ERIC Educational Resources Information Center

    Sebastian-Galles, N.; Echeverria, S.; Bosch, L.

    2005-01-01

    The representation of L2 words and non-words was analysed in a series of three experiments. Catalan-Spanish bilinguals, differing in terms of their L1 and the age of exposure to their L2 (since birth-simultaneous bilinguals-or starting in early childhood-early sequential bilinguals), were asked to perform a lexical decision task on Catalan words…

  3. Exposure of the human body to professional and domestic induction cooktops compared to the basic restrictions.

    PubMed

    Christ, Andreas; Guldimann, René; Bühlmann, Barbara; Zefferer, Marcel; Bakker, Jurriaan F; van Rhoon, Gerard C; Kuster, Niels

    2012-12-01

    We investigated whether domestic and professional induction cooktops comply with the basic restrictions defined by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Based on magnetic field measurements, a generic numerical model of an induction cooktop was derived in order to model user exposure. The current density induced in the user was simulated for various models and distances. We also determined the exposure of the fetus and of young children. While most measured cooktops comply with the public exposure limits at the distance specified by the International Electrotechnical Commission (standard IEC 62233), the majority exceeds them at closer distances, some of them even the occupational limits. The maximum current density in the tissue of the user significantly exceeds the basic restrictions for the general public, reaching the occupational level. The exposure of the brains of young children reaches the order of magnitude of the limits for the general public. For a generic worst-case cooktop compliant with the measurement standards, the current density exceeds the 1998 ICNIRP basic restrictions by up to 24 dB or a factor of 16. The brain tissue of young children can be overexposed by 6 dB or a factor of 2. The exposure of the tissue of the central nervous system of the fetus can exceed the limits for the general public if the mother is exposed at occupational levels. This demonstrates that the methodology for testing induction cooktops according to IEC 62233 contradicts the basic restrictions. This evaluation will be extended considering

  4. Analysis of Noise Exposure Measurements Made Onboard the International Space Station

    NASA Technical Reports Server (NTRS)

    Limardo, Jose G.; Allen, Christopher S.

    2011-01-01

    The International Space Station (ISS) is a unique workplace environment for U.S. astronauts and Russian cosmonauts to conduct research and live for a period of six months or more. Noise has been an enduring environmental physical hazard that has been a challenge for the U.S. space program since before the Apollo era. Noise exposure in ISS poses significant risks to the crewmembers, such as; hearing loss (temporary or permanent), possible disruptions of crew sleep, interference with speech intelligibility and communication, possible interference with crew task performance, and possible reduction in alarm audibility. Acoustic measurements are made aboard ISS and compared to requirements in order to assess the acoustic environment to which the crewmembers are exposed. The purpose of this paper is to describe in detail the noise exposure monitoring program as well as an assessment of the acoustic dosimeter data collected to date. The hardware currently being used for monitoring the noise exposure onboard ISS will be discussed. Acoustic data onboard ISS has been collected since the beginning of ISS (Increment 1, November 2000). Noise exposure data analysis will include acoustic dosimetry logged data from crew-worn during work and sleep periods and also fixed-location measurements from Increment 1 to present day. Noise exposure levels (8-, 16- and 24-hr), LEQ, will also be provided and discussed in this paper. Discussions related to hearing protection will also be included. Future directions and recommendations for the noise exposure monitoring program will be highlighted. This acoustic data is used to ensure a safe and healthy working and living environment for the crewmembers aboard the ISS.

  5. Analysis of Noise Exposure Measurements Acquired Onboard the International Space Station

    NASA Technical Reports Server (NTRS)

    Limardo, Jose G.; Allen, Christopher S.

    2011-01-01

    The International Space Station (ISS) is a unique workplace environment for U.S. astronauts and Russian cosmonauts to conduct research and live for a period of six months or more. Noise has been an enduring environmental physical hazard that has been a challenge for the U.S. space program since before the Apollo era. Noise exposure in ISS poses significant risks to the crewmembers, such as; hearing loss (temporary or permanent), possible disruptions of crew sleep, interference with speech intelligibility and communication, possible interference with crew task performance, and possible reduction in alarm audibility. Acoustic measurements were made onboard ISS and compared to requirements in order to assess the acoustic environment to which the crewmembers are exposed. The purpose of this paper is to describe in detail the noise exposure monitoring program as well as an assessment of the acoustic dosimeter data collected to date. The hardware currently being used for monitoring the noise exposure onboard ISS will be discussed. Acoustic data onboard ISS has been collected since the beginning of ISS (Increment 1, November 2001). Noise exposure data analysis will include acoustic dosimetry logged data from crew-worn dosimeters during work and sleep periods and also fixed-location measurements from Increment 1 to present day. Noise exposure levels (8-, 16- and 24-hr), LEQ, will also be provided and discussed in this paper. Future directions and recommendations for the noise exposure monitoring program will be highlighted. This acoustic data is used to ensure a safe and healthy working and living environment for the crewmembers onboard the ISS.

  6. ANALYSIS OF HUMAN ACTIVITY DATA FOR USE IN MODELING ENVIRONMENTAL EXPOSURES

    EPA Science Inventory

    Human activity data are a critical part of exposure models being developed by the US EPA's National Exposure Research Laboratory (NERL). An analysis of human activity data within NERL's Consolidated Human Activity Database (CHAD) was performed in two areas relevant to exposure ...

  7. The Effect of DEM Quality on Sea Level Rise Exposure Analysis

    NASA Astrophysics Data System (ADS)

    Kulp, S. A.; Strauss, B.

    2015-12-01

    Sea level rise (SLR) caused by climate change could cause significant disruptions in coastal communities across the world. Current projections estimate that we may see in the vicinity of 1 meter of SLR by the end of the century, and due to collapsing ice sheets in West Antarctica, more than 3 meters of global SLR appear very likely in the long run. It is therefore crucial that we begin to accurately understand both the short- and long-term effects this level of flooding could have on each country's land area and population. However, while we have high-resolution digital elevation models (DEMs) publicly available for some parts of the world, such as the coastal lidar datasets distributed by NOAA for the US, most of the rest of the world is only covered by much poorer-quality data, such as data from SRTM (3 arcsec, or roughly 90m, horizontal resolution). In this work, we perform SLR analysis using both NOAA lidar- and SRTM-derived DEMs in the United States, in order to understand how using low-quality DEMs affect the final analysis results. We find that in many states, the computed population exposure at 1 meter SLR is over 2x higher when using the Lidar DEM, compared to the results computed from SRTM. In addition to the clear differences in horizontal resolution, this very large difference in computed exposure could likely be explained by the fact that SRTM is based on surface elevation, while the Lidar DEM is based on bare earth elevation. We therefore conclude that any worldwide SLR analysis using SRTM would produce exposure estimates that are far too low, and higher-quality global DEMs are necessary in order to generate exposure analysis of reasonable accuracy.

  8. A Bayesian analysis of plutonium exposures in Sellafield workers.

    PubMed

    Puncher, M; Riddell, A E

    2016-03-01

    The joint Russian (Mayak Production Association) and British (Sellafield) plutonium worker epidemiological analysis, undertaken as part of the European Union Framework Programme 7 (FP7) SOLO project, aims to investigate potential associations between cancer incidence and occupational exposures to plutonium using estimates of organ/tissue doses. The dose reconstruction protocol derived for the study makes best use of the most recent biokinetic models derived by the International Commission on Radiological Protection (ICRP) including a recent update to the human respiratory tract model (HRTM). This protocol was used to derive the final point estimates of absorbed doses for the study. Although uncertainties on the dose estimates were not included in the final epidemiological analysis, a separate Bayesian analysis has been performed for each of the 11 808 Sellafield plutonium workers included in the study in order to assess: A. The reliability of the point estimates provided to the epidemiologists and B. The magnitude of the uncertainty on dose estimates. This analysis, which accounts for uncertainties in biokinetic model parameters, intakes and measurement uncertainties, is described in the present paper. The results show that there is excellent agreement between the point estimates of dose and posterior mean values of dose. However, it is also evident that there are significant uncertainties associated with these dose estimates: the geometric range of the 97.5%:2.5% posterior values are a factor of 100 for lung dose, 30 for doses to liver and red bone marrow, and 40 for intakes: these uncertainties are not reflected in estimates of risk when point doses are used to assess them. It is also shown that better estimates of certain key HRTM absorption parameters could significantly reduce the uncertainties on lung dose in future studies.

  9. An innovative land use regression model incorporating meteorology for exposure analysis.

    PubMed

    Su, Jason G; Brauer, Michael; Ainslie, Bruce; Steyn, Douw; Larson, Timothy; Buzzelli, Michael

    2008-02-15

    The advent of spatial analysis and geographic information systems (GIS) has led to studies of chronic exposure and health effects based on the rationale that intra-urban variations in ambient air pollution concentrations are as great as inter-urban differences. Such studies typically rely on local spatial covariates (e.g., traffic, land use type) derived from circular areas (buffers) to predict concentrations/exposures at receptor sites, as a means of averaging the annual net effect of meteorological influences (i.e., wind speed, wind direction and insolation). This is the approach taken in the now popular land use regression (LUR) method. However spatial studies of chronic exposures and temporal studies of acute exposures have not been adequately integrated. This paper presents an innovative LUR method implemented in a GIS environment that reflects both temporal and spatial variability and considers the role of meteorology. The new source area LUR integrates wind speed, wind direction and cloud cover/insolation to estimate hourly nitric oxide (NO) and nitrogen dioxide (NO(2)) concentrations from land use types (i.e., road network, commercial land use) and these concentrations are then used as covariates to regress against NO and NO(2) measurements at various receptor sites across the Vancouver region and compared directly with estimates from a regular LUR. The results show that, when variability in seasonal concentration measurements is present, the source area LUR or SA-LUR model is a better option for concentration estimation.

  10. Population exposure to ultraviolet radiation in Finland 1920-1995: Exposure trends and a time-series analysis of exposure and cutaneous melanoma incidence

    SciTech Connect

    Kojo, Katja . E-mail: katja.kojo@uta.fi; Jansen, Christer T.; Nybom, Pia; Huurto, Laura; Laihia, Jarmo; Ilus, Taina; Auvinen, Anssi

    2006-05-15

    Ultraviolet radiation (UVR) is the principal cause of cutaneous malignant melanoma (CMM). However, the relation between CMM and UVR exposure is not clear. We present the trends of population exposure to UVR and conduct a time-series analysis of the relation between UVR exposure and incidence of CMM. Data on CMM incidence were obtained from the Finnish Cancer Registry. Clothing coverage of the body was scored from archival photographs and the proportion of uncovered skin was used as a measure of solar exposure. Information on the number of sunny resort holidays, duration of annual holidays, and sunscreen sales were obtained from various sources. Exposed skin area doubled from 1920 to 1985. The average duration of annual holidays increased 30-fold. The number of sunny resort holidays and the sales of sunscreens increased rapidly from 1980. CMM was most strongly associated with solar exposure of 5-19 years earlier. There is a considerable decrease in clothing coverage during the 20th century. UVR exposure preceding CMM occurrence 4 years or less does not appear relevant, whereas the period 5-19 years prior to CMM occurrence might be the most relevant period. However, findings of ecological studies may not be applicable at the individual level.

  11. Comparative performance of geopolymers made with metakaolin and fly ash after exposure to elevated temperatures

    SciTech Connect

    Kong, Daniel L.Y.; Sanjayan, Jay G. Sagoe-Crentsil, Kwesi

    2007-12-15

    This paper presents the results of a study on the effect of elevated temperatures on geopolymers manufactured using metakaolin and fly ash of various mixture proportions. Both types of geopolymers (metakaolin and fly ash) were synthesized with sodium silicate and potassium hydroxide solutions. The strength of the fly ash-based geopolymer increased after exposure to elevated temperatures (800 deg. C). However, the strength of the corresponding metakaolin-based geopolymer decreased after similar exposure. Both types of geopolymers were subjected to thermogravimetric, scanning electron microscopy and mercury intrusion porosimetry tests. The paper concludes that the fly ash-based geopolymers have large numbers of small pores which facilitate the escape of moisture when heated, thus causing minimal damage to the geopolymer matrix. On the other hand, metakaolin geopolymers do not possess such pore distribution structures. The strength increase in fly ash geopolymers is also partly attributed to the sintering reactions of un-reacted fly ash particles.

  12. Comparing plasma and X-ray exposure and identifying vulnerable cell parts

    NASA Astrophysics Data System (ADS)

    Graham, Bill

    2012-10-01

    Here two issues in plasma medicine that are being addressed in a collaboration between the Centre of Plasma Physics and the School of Pharmacy at Queen's University Belfast and the Plasma Institute at York University UK will be discussed. Recent measurements of the interaction of plasmas created directly in DMEM cell medium and MDAMB-231, a human breast cancer cell line, showed evidence of reduced cell viability and of DNA damage. The same set of experiments were undertaken but with X-ray exposure. A correlation of the dependence on plasma exposure time and X-ray dose was observed which might point the way to dose definition in plasma medicine. We have also been working to identify the cell parts most vulnerable to plasma exposure. In this study a 10 kHz atmospheric pressure non-thermal plasma jet, operating in He/0.5%O2 and characterized to determine the behavior of many of the plasma species, was incident onto the surface of media containing either bacterial strains, in their planktonic and biofilm forms, or isolated bacterial plasmid DNA. The results of measurements to look for changes in plasmid structural conformation, rates of single and double strand breaks, the catalytic activity of certain bacterial enzymes, the peroxidation of lipid content of the bacterial cells, the leakage of ATP and Scanning Electron Microscope (SEM) images will be discussed.

  13. A review of surface wipe sampling compared to biologic monitoring for occupational exposure to antineoplastic drugs.

    PubMed

    Kibby, Thomas

    2017-03-01

    The potential for adverse health effects from occupational exposure to antineoplastic drugs (AD) is well known. Control measures recommended by the NIOSH Alert ([3]) include medical and biologic monitoring, and environmental monitoring where available. At present no guidelines or published best practices exist to guide EHS managers on how to carry out this biologic or environmental monitoring. Studies investigating surface wipe sampling for AD have been numerous in the past decade, but very limited research exists to correlate surface contamination with actual absorption by pharmacists and nurses. This article reviews the studies with concurrent surface wipe sampling and urine monitoring for the same AD, and tests their correlation. Methodologic limitations are reviewed. Twenty-one studies were identified that concurrently measured surface contamination by AD by wipe sampling and AD absorption by urine monitoring. Two studies directly evaluated the AD by wipe sampling and urine levels and neither found a statistically significant correlation. Six studies reported a decrease in both surface and urine levels following interventions to reduce contamination or exposure. Only one study directly evaluated the personal protective equipment and handling techniques employed by the studied workers, which can be viewed as a major confounder of absorption. While no statistically significant correlation was found between wipe sampling and urine monitoring for AD, decreases in urine and wipe levels following interventions to reduce exposure were noted. Limitations in the data and recommendations for future research are reviewed.

  14. Optimal attentional focus during exposure in specific phobia: a meta-analysis.

    PubMed

    Podină, Ioana R; Koster, Ernst H W; Philippot, Pierre; Dethier, Vincent; David, Daniel O

    2013-12-01

    Over the last 30 years, researchers have disagreed over the consequences of diverting attention from threat for exposure efficacy, which is an important theoretical and clinical debate. Therefore, the present meta-analysis assessed the efficacy of attentionally focused exposure against distracted and attentionally uninstructed exposure regarding distress, behavioral, and physiological outcomes. We included 15 randomized studies with specific phobia, totaling 444 participants and targeting outcomes at post-exposure and follow-up. Results indicated no difference between the efficacy of distracted exposure as opposed to focused or uninstructed exposure for distress and physiology. For behavior, at post-exposure, results were marginally significant in favor of distracted as opposed to focused exposure, while at follow-up results significantly favored distraction. However, concerning behavior, uninstructed exposure was superior to distraction. Moderation analyses revealed that, regarding distress reduction and approach behavior, distracted exposure significantly outperformed focused exposure when the distracter was interactive (g=1.010/g=1.128) and exposure was spread over the course of multiple sessions (g=1.527/g=1.606). No moderation analysis was significant for physiological measures. These findings suggest that distraction during exposure could be less counterproductive than previously considered and even beneficial under certain circumstances. Theoretical implications and future directions for research are discussed.

  15. Comparative MicroRNA Expression Patterns in Fibroblasts after Low and High Doses of Low-LET Radiation Exposure

    NASA Technical Reports Server (NTRS)

    Maes, Olivier C.; Xu, Suying; Hada, Megumi; Wu, Honglu; Wang, Eugenia

    2007-01-01

    Exposure to ionizing radiation causes DNA damage to cells, and provokes a plethora of cellular responses controlled by unique gene-directed signaling pathways. MicroRNAs (miRNAs) are small (22-nucleotide), non-coding RNAs which functionally silence gene expression by either degrading the messages or inhibiting translation. Here we investigate radiation-dependent changes in these negative regulators by comparing the expression patterns of all 462 known human miRNAs in fibroblasts, after exposure to low (0.1 Gy) or high (2 Gy) doses of X-rays at 30 min, 2, 6 and 24 hrs post-treatment. The expression patterns of microRNAs after low and high doses of radiation show a similar qualitative down-regulation trend at early (0.5 hr) and late (24 hr) time points, with a quantitatively steeper slope following the 2 Gy exposures. Interestingly, an interruption of this downward trend is observed after the 2 Gy exposure, i.e. a significant up-regulation of microRNAs at 2 hrs, then reverting to the downward trend by 6 hrs; this interruption at the intermediate time point was not observed with the 0.1 Gy exposure. At the early time point (0.5 hr), candidate gene targets of selected down-regulated microRNAs, common to both 0.1 and 2 Gy exposures, were those functioning in chromatin remodeling. Candidate target genes of unique up-regulated microRNAs seen at a 2 hr intermediate time point, after the 2 Gy exposure only, are those involved in cell death signaling. Finally, putative target genes of down-regulated microRNAs seen at the late (24 hr) time point after either doses of radiation are those involved in the up-regulation of DNA repair, cell signaling and homeostasis. Thus we hypothesize that after radiation exposure, microRNAs acting as hub negative regulators for unique signaling pathways needed to be down-regulated so as to de-repress their target genes for the proper cellular responses, including DNA repair and cell maintenance. The unique microRNAs up-regulated at 2 hr after 2

  16. Role of exposure analysis in solving the mystery of Balkan endemic nephropathy.

    PubMed

    Long, David T; Voice, Thomas C

    2007-06-01

    We evaluated the role of exposure analysis in assessing whether ochratoxin A or aristolochic acid are the agents responsible for causing Balkan endemic nephropathy. We constructed a framework for exposure analysis using the lessons learned from the study of endemic goiter within the context of an accepted general model. We used this framework to develop an exposure analysis model for Balkan endemic nephropathy, evaluated previous findings from the literature on ochratoxin A and aristolochic acid in the context of this model, discussed the strength of evidence for each, and proposed approaches to address critical outstanding questions. The pathway for exposure to ochratoxin A is well defined and there is evidence that humans have ingested ochratoxin A. Factors causing differential exposure to ochratoxin A and how ochratoxin A is implicated in Balkan endemic nephropathy are not defined. Although there is evidence of human exposure to aristolochic acid and that its effects are consistent with Balkan endemic nephropathy, a pathway for exposure to aristolochic acid has been suggested but not demonstrated. Factors causing differential exposure to aristolochic acid are not known. Exposure analysis results suggest that neither ochratoxin A nor aristolochic acid can be firmly linked to Balkan endemic nephropathy. However, this approach suggests future research directions that could provide critical evidence on exposure, which when linked with findings from the health sciences, may be able to demonstrate the cause of this disease and provide a basis for effective public health intervention strategies. One of the key unknowns for both agents is how differential exposure can occur.

  17. Role of Exposure Analysis in Solving the Mystery of Balkan Endemic Nephropathy

    PubMed Central

    Long, David T.; Voice, Thomas C.

    2007-01-01

    We evaluated the role of exposure analysis in assessing whether ochratoxin A aristolochic acid are the agents responsible for causing Balkan endemic nephropathy. We constructed a framework for exposure analysis using the lessons learned from the study of endemic goiter within the context of an accepted general model. We used this framework to develop an exposure analysis model for Balkan endemic nephropathy, evaluated previous findings from the literature on ochratoxin A and aristolochic acid in the context of this model, discussed the strength of evidence for each, and proposed approaches to address critical outstanding questions. The pathway for exposure to ochratoxin A is well defined and there is evidence that humans have ingested ochratoxin A. Factors causing differential exposure to ochratoxin A and how ochratoxin A is implicated in Balkan endemic nephropathy are not defined. Although there is evidence of human exposure to aristolochic acid and that its effects are consistent with Balkan endemic nephropathy, a pathway for exposure to aristolochic acid has been suggested but not demonstrated. Factors causing differential exposure to aristolochic acid are not known. Exposure analysis results suggest that neither ochratoxin A nor aristolochic acid can be firmly linked to Balkan endemic nephropathy. However, this approach suggests future research directions that could provide critical evidence on exposure, which when linked with findings from the health sciences, may be able to demonstrate the cause of this disease and provide a basis for effective public health intervention strategies. One of the key unknowns for both agents is how differential exposure can occur. PMID:17589972

  18. Analysis of Intervention Strategies for Inhalation Exposure to Polycyclic Aromatic Hydrocarbons and Associated Lung Cancer Risk Based on a Monte Carlo Population Exposure Assessment Model

    PubMed Central

    Zhou, Bin; Zhao, Bin

    2014-01-01

    It is difficult to evaluate and compare interventions for reducing exposure to air pollutants, including polycyclic aromatic hydrocarbons (PAHs), a widely found air pollutant in both indoor and outdoor air. This study presents the first application of the Monte Carlo population exposure assessment model to quantify the effects of different intervention strategies on inhalation exposure to PAHs and the associated lung cancer risk. The method was applied to the population in Beijing, China, in the year 2006. Several intervention strategies were designed and studied, including atmospheric cleaning, smoking prohibition indoors, use of clean fuel for cooking, enhancing ventilation while cooking and use of indoor cleaners. Their performances were quantified by population attributable fraction (PAF) and potential impact fraction (PIF) of lung cancer risk, and the changes in indoor PAH concentrations and annual inhalation doses were also calculated and compared. The results showed that atmospheric cleaning and use of indoor cleaners were the two most effective interventions. The sensitivity analysis showed that several input parameters had major influence on the modeled PAH inhalation exposure and the rankings of different interventions. The ranking was reasonably robust for the remaining majority of parameters. The method itself can be extended to other pollutants and in different places. It enables the quantitative comparison of different intervention strategies and would benefit intervention design and relevant policy making. PMID:24416436

  19. Understanding workers' exposure: Systematic review and data-analysis of emission potential for NOAA.

    PubMed

    Kuijpers, E; Bekker, C; Brouwer, D; le Feber, M; Fransman, W

    2017-05-01

    Exposure assessment for nano-objects, and their aggregates and agglomerates (NOAA), has evolved from explorative research toward more comprehensive exposure assessment, providing data to further develop currently used conservative control banding (CB) tools for risk assessment. This study aims to provide an overview of current knowledge on emission potential of NOAA across the occupational life cycle stages by a systematic review and subsequently use the results in a data analysis. Relevant parameters that influence emission were collected from peer-reviewed literature with a focus on the four source domains (SD) in the source-receptor conceptual framework for NOAA. To make the reviewed exposure data comparable, we applied an approach to normalize for workplace circumstances and measurement location, resulting in comparable "surrogate" emission levels. Finally, descriptive statistics were performed. During the synthesis of nanoparticles (SD1), mechanical reduction and gas phase synthesis resulted in the highest emission compared to wet chemistry and chemical vapor condensation. For the handling and transfer of bulk manufactured nanomaterial powders (SD2) the emission could be differentiated for five activity classes: (1) harvesting; (2) dumping; (3); mixing; (4) cleaning of a reactor; and (5) transferring. Additionally, SD2 was subdivided by the handled amount with cleaning further subdivided by energy level. Harvesting and dumping resulted in the highest emissions. Regarding processes with liquids (SD3b), it was possible to distinguish emissions for spraying (propellant gas, (high) pressure and pump), sonication and brushing/rolling. The highest emissions observed in SD3b were for propellant gas spraying and pressure spraying. The highest emissions for the handling of nano-articles (SD4) were found to nano-sized particles (including NOAA) for grinding. This study provides a valuable overview of emission assessments performed in the workplace during the

  20. Analysis of multiple exposures in the case-crossover design via sparse conditional likelihood.

    PubMed

    Avalos, Marta; Grandvalet, Yves; Adroher, Nuria Duran; Orriols, Ludivine; Lagarde, Emmanuel

    2012-09-20

    We adapt the least absolute shrinkage and selection operator (lasso) and other sparse methods (elastic net and bootstrapped versions of lasso) to the conditional logistic regression model and provide a full R implementation. These variable selection procedures are applied in the context of case-crossover studies. We study the performances of conventional and sparse modelling strategies by simulations, then empirically compare results of these methods on the analysis of the association between exposure to medicinal drugs and the risk of causing an injurious road traffic crash in elderly drivers. Controlling the false discovery rate of lasso-type methods is still problematic, but this problem is also present in conventional methods. The sparse methods have the ability to provide a global analysis of dependencies, and we conclude that some of the variants compared here are valuable tools in the context of case-crossover studies with a large number of variables.

  1. Memory deficits and industrial toxicant exposure: a comparative study of hard metal, solvent and asbestos workers.

    PubMed

    Jordan, C M; Whitman, R D; Harbut, M

    1997-06-01

    Memory functioning was examined in ex-factory workers with hard metal disease, resulting from exposure to alloys utilizing cobalt. Since these workers are also exposed to organic solvents and may suffer from chronic hypoxia as a result of their pulmonary disorder, solvent and asbestos workers, as well as an unexposed matched sample, served as controls. Results demonstrated deficits in the allocation of attentional resources and in short-term verbal memory. A pattern of findings across several tests suggested that repetition or delay is important for adequate memory performance in individuals exposed to hard metal, implicating a deficit in encoding or slowed consolidation.

  2. An Analysis of Sound Exposure in a University Music Rehearsal

    ERIC Educational Resources Information Center

    Farmer, Joe; Thrasher, Michael; Fumo, Nelson

    2014-01-01

    Exposure to high sound levels may lead to a variety of hearing abnormalities, including Noise-Induced Hearing Loss (NIHL). Pre-professional university music majors may experience frequent exposure to elevated sound levels, and this may have implications on their future career prospects (Jansen, Helleman, Dreschler & de Laat, 2009). Studies…

  3. MIXED MODELS ANALYSIS OR URBANIZATION LEVEL ON CHLORPYRIFOS EXPOSURE

    EPA Science Inventory

    The National Human Exposure Assessment Survey (NHEXAS) pilot studies were conducted from 1995 through 1997 to examine human population exposure to a wide range of environmental contaminants. In one of the studies, NHEXAS-Maryland, a longitudinal design was used to repeatedly m...

  4. Personal Exposure to Mixtures of Volatile Organic Compounds: Modeling and Further Analysis of the RIOPA Data

    PubMed Central

    Batterman, Stuart; Su, Feng-Chiao; Li, Shi; Mukherjee, Bhramar; Jia, Chunrong

    2015-01-01

    known to affect VOC exposures, many personal, environmental, and socioeconomic determinants remain to be identified, and the significance and applicability of the determinants reported in the literature are uncertain. To help answer these unresolved questions and overcome limitations of previous analyses, this project used several novel and powerful statistical modeling and analysis techniques and two large data sets. The overall objectives of this project were (1) to identify and characterize exposure distributions (including extreme values), (2) evaluate mixtures (including dependencies), and (3) identify determinants of VOC exposure. METHODS VOC data were drawn from two large data sets: the Relationships of Indoor, Outdoor, and Personal Air (RIOPA) study (1999–2001) and the National Health and Nutrition Examination Survey (NHANES; 1999–2000). The RIOPA study used a convenience sample to collect outdoor, indoor, and personal exposure measurements in three cities (Elizabeth, NJ; Houston, TX; Los Angeles, CA). In each city, approximately 100 households with adults and children who did not smoke were sampled twice for 18 VOCs. In addition, information about 500 variables associated with exposure was collected. The NHANES used a nationally representative sample and included personal VOC measurements for 851 participants. NHANES sampled 10 VOCs in common with RIOPA. Both studies used similar sampling methods and study periods. Specific Aim 1 To estimate and model extreme value exposures, extreme value distribution models were fitted to the top 10% and 5% of VOC exposures. Health risks were estimated for individual VOCs and for three VOC mixtures. Simulated extreme value data sets, generated for each VOC and for fitted extreme value and lognormal distributions, were compared with measured concentrations (RIOPA observations) to evaluate each model’s goodness of fit. Mixture distributions were fitted with the conventional finite mixture of normal distributions and the

  5. Analysis of the individual risk of altitude decompression sickness under repeated exposures

    NASA Technical Reports Server (NTRS)

    Kumar, K. Vasantha; Horrigan, David J.; Waligora, James M.; Gilbert, John H.

    1991-01-01

    In a case-control study, researchers examined the risk of decompression sickness (DCS) in individual subjects with higher number of exposures. Of the 126 subjects, 42 showed one or more episodes of DCS. Examination of the exposure-DCS relationship by odds ratio showed a linear relationship. Stratification analysis showed that sex, tissue ratio, and the presence of Doppler microbubbles were cofounders of this risk. A higher number of exposures increased the risk of DCS in this analysis.

  6. Comparative Study of Several Behaviors in Caenorhabditis Elegans Following High-Let Radiation Exposure

    NASA Astrophysics Data System (ADS)

    Sakashita, Tetsuya

    Learning and behavioral impairments following ionizing radiation exposure are an important potential risk in manned space missions. We previously reported the effects of γ-ray exposure on olfactory adaptation [1], salt chemotaxis learning [2], and locomotion - learning behavior relationship [3] in Caenorhabditis elegans. However, little is known about the effects of high linear energy transfer (LET) radiation. We investigated various behavioral responses of wellfed adult Caenorhabditis elegans exposed to accelerated carbon ions (1 2C, 18.3M eV /u, LET = 113.3keV /µm). Following carbon-ion irradiation, locomotion, basal slowing response and salt chemotaxis learning were not significantly affected, whereas chemosensation to NaCl of animals during learning was altered. These results suggest that sensitivity of the C. elegans nervous system to high-LET heavy ions differs with the types of behaviors. References: [1] Sakashita et al., Biol. Sci. Space 21, 117-20 (2007), [2] Sakashita et al., FASEB J 22, 713-20 (2008), [3] Sakashita et al., J. Radiat. Res. 49, in press (2008).

  7. Integrating Landsat and California pesticide exposure estimation at aggregated analysis scales: Accuracy assessment of rurality

    NASA Astrophysics Data System (ADS)

    Vopham, Trang Minh

    Pesticide exposure estimation in epidemiologic studies can be constrained to analysis scales commonly available for cancer data - census tracts and ZIP codes. Research goals included (1) demonstrating the feasibility of modifying an existing geographic information system (GIS) pesticide exposure method using California Pesticide Use Reports (PURs) and land use surveys to incorporate Landsat remote sensing and to accommodate aggregated analysis scales, and (2) assessing the accuracy of two rurality metrics (quality of geographic area being rural), Rural-Urban Commuting Area (RUCA) codes and the U.S. Census Bureau urban-rural system, as surrogates for pesticide exposure when compared to the GIS gold standard. Segments, derived from 1985 Landsat NDVI images, were classified using a crop signature library (CSL) created from 1990 Landsat NDVI images via a sum of squared differences (SSD) measure. Organochlorine, organophosphate, and carbamate Kern County PUR applications (1974-1990) were matched to crop fields using a modified three-tier approach. Annual pesticide application rates (lb/ac), and sensitivity and specificity of each rurality metric were calculated. The CSL (75 land use classes) classified 19,752 segments [median SSD 0.06 NDVI]. Of the 148,671 PUR records included in the analysis, Landsat contributed 3,750 (2.5%) additional tier matches. ZIP Code Tabulation Area (ZCTA) rates ranged between 0 and 1.36 lb/ac and census tract rates between 0 and 1.57 lb/ac. Rurality was a mediocre pesticide exposure surrogate; higher rates were observed among urban areal units. ZCTA-level RUCA codes offered greater specificity (39.1-60%) and sensitivity (25-42.9%). The U.S. Census Bureau metric offered greater specificity (92.9-97.5%) at the census tract level; sensitivity was low (≤6%). The feasibility of incorporating Landsat into a modified three-tier GIS approach was demonstrated. Rurality accuracy is affected by rurality metric, areal aggregation, pesticide chemical

  8. Bivariate Left-Censored Bayesian Model for Predicting Exposure: Preliminary Analysis of Worker Exposure during the Deepwater Horizon Oil Spill.

    PubMed

    Groth, Caroline; Banerjee, Sudipto; Ramachandran, Gurumurthy; Stenzel, Mark R; Sandler, Dale P; Blair, Aaron; Engel, Lawrence S; Kwok, Richard K; Stewart, Patricia A

    2017-01-01

    In April 2010, the Deepwater Horizon oil rig caught fire and exploded, releasing almost 5 million barrels of oil into the Gulf of Mexico over the ensuing 3 months. Thousands of oil spill workers participated in the spill response and clean-up efforts. The GuLF STUDY being conducted by the National Institute of Environmental Health Sciences is an epidemiological study to investigate potential adverse health effects among these oil spill clean-up workers. Many volatile chemicals were released from the oil into the air, including total hydrocarbons (THC), which is a composite of the volatile components of oil including benzene, toluene, ethylbenzene, xylene, and hexane (BTEXH). Our goal is to estimate exposure levels to these toxic chemicals for groups of oil spill workers in the study (hereafter called exposure groups, EGs) with likely comparable exposure distributions. A large number of air measurements were collected, but many EGs are characterized by datasets with a large percentage of censored measurements (below the analytic methods' limits of detection) and/or a limited number of measurements. We use THC for which there was less censoring to develop predictive linear models for specific BTEXH air exposures with higher degrees of censoring. We present a novel Bayesian hierarchical linear model that allows us to predict, for different EGs simultaneously, exposure levels of a second chemical while accounting for censoring in both THC and the chemical of interest. We illustrate the methodology by estimating exposure levels for several EGs on the Development Driller III, a rig vessel charged with drilling one of the relief wells. The model provided credible estimates in this example for geometric means, arithmetic means, variances, correlations, and regression coefficients for each group. This approach should be considered when estimating exposures in situations when multiple chemicals are correlated and have varying degrees of censoring.

  9. Comparative sensitivity of juvenile and adult Potamopyrgus antipodarum (Mollusca: Hydrobiidae) under chronic exposure to cadmium and tributyltin.

    PubMed

    Ruppert, Katharina; Geiß, Cornelia; Ostermann, Sina; Theis, Christina; Oehlmann, Jörg

    2016-07-28

    To investigate a potential extension of a partial life cycle test protocol to a full life cycle test design, a comparative sensitivity analysis with juvenile and adult Potamopyrgus antipodarum was performed. Neonates and adult snails were exposed to the metal cadmium (Cd) and the endocrine disruptor tributyltin (TBT) at nominal concentrations ranging from 1.56 to 50 μg Cd/L and from 25 to 1,000 ng TBT-Sn/L. The experiments were performed over 28 days at 16°C in a semi-static test design. Mortality was assessed for both life stages. Juvenile snails' specific growth rate and reproduction of adults were investigated as main endpoints. We determined effects on snails' survival, juvenile growth and embryo numbers in the brood pouch of adult snails under exposure to both chemicals. Juvenile control mortality was between 25% and 30% and significantly higher than in the control groups with adult snails. A higher sensitivity of juvenile snails compared to adults was observed for the endpoint mortality. Calculated LC50 in Cd exposed snails was 38.2 μg/L for adults and 15.0 μg/L for juvenile snails. Significant effects on mortality in TBT exposed adult snails occurred at the highest test concentration only with a LC50 of 535 ng Sn/L. Juvenile survival was significantly affected at 50.8 ng Sn/L and higher concentrations. Effect concentrations for the main endpoints reproduction and juvenile growth show comparable sensitivities. For Cd exposed groups, EC50 values were 11.3 μg/L for the endpoint reproduction in adult snails and 3.82 μg/L for juvenile growth with overlapping confidence intervals. TBT also significantly affected juvenile snails' growth (EC50: 178 ng Sn /L). EC50 for embryo numbers was 125 ng TBT-Sn/L. Results indicate the manageability of a FLC test starting with newly hatched snails. Precautions have to be taken to guarantee a sufficient number of surviving snails until adulthood so that reproduction can be assessed. For final decision for the

  10. A comparative study on the varying exposure to atmospheric fine and coarse particles under urban and rural conditions.

    PubMed

    Wolf-Benning, Uta; Schultz, Eckart; Dietze, Volker; Kaminski, Uwe; Endlicher, Wilfried

    2012-11-01

    This paper is based on the results of three air quality studies conducted in Buenos Aires in Berlin, and in German spas between 2003 and 2007. A high comparability of results was ensured by using the same sampling techniques and analytical methods. Total particle sampling was achieved by active sampling of fine (PM2.5) and passive sampling of coarse particles > or = 2.5 microm and giant particles > or = 10 microm. The highly absorbing, black, predominantly carbonaceous particles (BC) of fine particle samples were determined by measuring the total light attenuation of filter samples and interpreting the extinction value as black carbon. The difference between the gravimetric total mass concentration of the PM2.5 samples and the BC is defined as the transparent, mostly mineral fine fraction. In coarse/giant particle samples the mean gray value was determined by means of automated light microscopy with subsequent single-particle analysis. "Opaque" particles were separated from the "transparent" particle fraction by applying a grey value threshold level. Microscopic measurement of individual particles was employed to establish the size distribution of the coarse and giant fraction. Due to different health effects, the separate detection of these components is suggested. Decline functions of particles are given, possibly providing useful information for a more detailed specification of the local particle distribution, and for a better estimate of the individual exposure. Atmospheric dispersal of particles was found effected mainly by source characteristics. An increased, spatially largely constant level of fine transparent particles in Berlin indicates a particle plume originating from photochemical processes. Buenos Aires, in contrast, is characterized by a lower background level of fine transparent particles but is considerably affected by fine black particles from diesel emissions and by a higher resuspension of coarse/giant transparent, mainly soil particles.

  11. Pain exposure physical therapy (PEPT) compared to conventional treatment in complex regional pain syndrome type 1: a randomised controlled trial

    PubMed Central

    Barnhoorn, Karlijn J; van de Meent, Henk; van Dongen, Robert T M; Klomp, Frank P; Groenewoud, Hans; Samwel, Han; Nijhuis-van der Sanden, Maria W G; Frölke, Jan Paul M; Staal, J Bart

    2015-01-01

    Objective To compare the effectiveness of pain exposure physical therapy (PEPT) with conventional treatment in patients with complex regional pain syndrome type 1 (CRPS-1) in a randomised controlled trial with a blinded assessor. Setting The study was conducted at a level 1 trauma centre in the Netherlands. Participants 56 adult patients with CRPS-1 participated. Three patients were lost to follow-up. Interventions Patients received either PEPT in a maximum of five treatment sessions, or conventional treatment following the Dutch multidisciplinary guideline. Measurements Outcomes were assessed at baseline and at 3, 6 and 9 months after randomisation. The primary outcome measure was the Impairment level Sum Score—Restricted Version (ISS-RV), consisting of visual analogue scale for pain (VAS-pain), McGill Pain Questionnaire, active range of motion (AROM) and skin temperature. Secondary outcome measures included Pain Disability Index (PDI); muscle strength; Short Form 36 (SF-36); disability of arm, shoulder and hand; Lower Limb Tasks Questionnaire (LLTQ); 10 m walk test; timed up-and-go test (TUG) and EuroQol-5D. Results The intention-to-treat analysis showed a clinically relevant decrease in ISS-RV (6.7 points for PEPT and 6.2 points for conventional treatment), but the between-group difference was not significant (0.96, 95% CI −1.56 to 3.48). Participants allocated to PEPT experienced a greater improvement in AROM (between-group difference 0.51, 95% CI 0.07 to 0.94; p=0.02). The per protocol analysis showed larger and significant between-group effects on ISS-RV, VAS-pain, AROM, PDI, SF-36, LLTQ and TUG. Conclusions We cannot conclude that PEPT is superior to conventional treatment for patients with CRPS-1. Further high-quality research on the effects of PEPT is warranted given the potential effects as indicated by the per protocol analysis. Trial registration numbers NCT00817128 and NTR 2090. PMID:26628523

  12. Sensitivity analysis for direct and indirect effects in the presence of exposure-induced mediator-outcome confounders

    PubMed Central

    Chiba, Yasutaka

    2014-01-01

    Questions of mediation are often of interest in reasoning about mechanisms, and methods have been developed to address these questions. However, these methods make strong assumptions about the absence of confounding. Even if exposure is randomized, there may be mediator-outcome confounding variables. Inference about direct and indirect effects is particularly challenging if these mediator-outcome confounders are affected by the exposure because in this case these effects are not identified irrespective of whether data is available on these exposure-induced mediator-outcome confounders. In this paper, we provide a sensitivity analysis technique for natural direct and indirect effects that is applicable even if there are mediator-outcome confounders affected by the exposure. We give techniques for both the difference and risk ratio scales and compare the technique to other possible approaches. PMID:25580387

  13. Aberrant cell divisions in root meristeme of maize following exposure to X-rays low doses compared to similar effects of 50 Hz electromagnetic exposure

    NASA Astrophysics Data System (ADS)

    Focea, R.; Capraru, G.; Racuciu, M.; Creanga, D.; Luchian, T.

    2012-04-01

    The response of maize to radiation exposure was investigated by two cytogenetic methods considering the importance of the geno-toxic effect for environmental and agricultural purposes. Uniform genophond seeds, freshly germinated, were exposed to relatively low radiation doses using a radiotherapy X-ray applicator from a hospital irradiation device and to a 50 Hz electromagnetic field with about 10 mT magnetic induction (generated within laboratory assembled electromagnetic coils). Radicular meristeme tissue aliquots were prevailed for cytogenetic investigation based on microscopic observations and cell counting. Microscope slides were prepared following a specific procedure (squash technique and Feulgen method based on modified Carr reactive coloration). Mitotic index as well as chromosomal aberration percentage were calculated for more than 30,000 cells taken into account. From a qualitative viewpoint, chromosomal aberrations such as interchromatidian bridges, lagging and expelled chromosomes and multipolar divisions were evidenced - no distinct situation for either ionizing radiation or electromagnetic field being identified. The main quantitative difference consisted in the increased mitotic index for electromagnetic exposure increased times compared with the diminished mitotic index in the case of low X-ray doses.

  14. Pathophysiology of tobacco smoke exposure: recent insights from comparative and redox proteomics.

    PubMed

    Colombo, Graziano; Clerici, Marco; Giustarini, Daniela; Portinaro, Nicola M; Aldini, Giancarlo; Rossi, Ranieri; Milzani, Aldo; Dalle-Donne, Isabella

    2014-01-01

    First-hand and second-hand tobacco smoke are causally linked to a huge number of deaths and are responsible for a broad spectrum of pathologies such as cancer, cardiovascular, respiratory, and eye diseases as well as adverse effects on female reproductive function. Cigarette smoke is a complex mixture of thousands of different chemical species, which exert their negative effects on macromolecules and biochemical pathways, both directly and indirectly. Many compounds can act as oxidants, pro-inflammatory agents, carcinogens, or a combination of these. The redox behavior of cigarette smoke has many implications for smoke related diseases. Reactive oxygen and nitrogen species (both radicals and non-radicals), reactive carbonyl compounds, and other species may induce oxidative damage in almost all the biological macromolecules, compromising their structure and/or function. Different quantitative and redox proteomic approaches have been applied in vitro and in vivo to evaluate, respectively, changes in protein expression and specific oxidative protein modifications induced by exposure to cigarette smoke and are overviewed in this review. Many gel-based and gel-free proteomic techniques have already been used successfully to obtain clues about smoke effects on different proteins in cell cultures, animal models, and humans. The further implementation with other sensitive screening techniques could be useful to integrate the comprehension of cigarette smoke effects on human health. In particular, the redox proteomic approach may also help identify biomarkers of exposure to tobacco smoke useful for preventing these effects or potentially predictive of the onset and/or progression of smoking-induced diseases as well as potential targets for therapeutic strategies.

  15. EMERGY ANALYSIS AND ECONOMIC ANALYSIS A COMPARATIVE STUDY

    EPA Science Inventory

    Our mission at USEPA is to protect human health and safeguard the natural environment. We aim to base our environmental regulations and policies on sound scientific and, where appropriate, economic analyses. Although EPA has conducted analysis of the impact of regulations on ...

  16. Acute nonhypothermic exposure to cold impedes motor skill performance in video gaming compared to thermo-neutral and hot conditions.

    PubMed

    Edwards, Andrew M; Crowther, Robert G; Morton, R Hugh; Polman, Remco C

    2011-02-01

    The study examined whether or not acute exposure to unfamiliar hot or cold conditions impairs performance of highly skilled coordinative activities and whether prior physical self-efficacy beliefs were associated with task completion. Nineteen volunteers completed both Guitar Hero and Archery activities as a test battery using the Nintendo Wii console in cold (2 degrees C), neutral (20 degrees C), and hot (38 degrees C) conditions. Participants all completed physical self-efficacy questionnaires following experimental familiarization. Performances of both Guitar Hero and Archery significantly decreased in the cold compared with the neutral condition. The cold trial was also perceived as the condition requiring both greater concentration and effort. There was no association between performance and physical self-efficacy. Performance of these coordinative tasks was compromised by acute (nonhypothermic) exposure to cold; the most likely explanation is that the cold condition presented a greater challenge to attentional processes as a form of environmental distraction.

  17. Advances in cosmogenic surface exposure dating: Using combined in situ 14C-10Be analysis for deglaciation scenarios

    NASA Astrophysics Data System (ADS)

    Hippe, Kristina; Ivy-Ochs, Susan; Kober, Florian; Christl, Marcus; Fogwill, Christopher; Turney, Chris; Rood, Dylan; Lupker, Maarten; Schlücher, Christian; Wieler, Rainer

    2016-04-01

    Cosmogenic nuclides are routinely used to investigate deglaciation histories by exposure dating of rock surfaces after glacier retreat. For bedrock surfaces that have been efficiently eroded by glacier ice, the most commonly applied cosmogenic 10Be isotope has proven to give reliable estimates of the integrated time of surface exposure since major ice decay. Due to its long half-life (~1.4 Ma), however, 10Be does not record short episodes of intermittent surface cover, e.g. during phases of glacier readvance, which might have interrupted the general deglaciation trend. To detect such cases of "complex exposure", 10Be-based dating can be combined with the analysis of the short-lived (5730 a) in situ cosmogenic 14C nuclide. We present two examples, in which combined in situ 14C-10Be analysis has been successfully applied to reconstruct in detail post-LGM surface exposures histories - in the Swiss Alps [1] and in Antarctica [2]. In a study on the Gotthard Pass, Central Swiss Alps, in situ 14C-10Be exposure dating was combined with extensive mapping of glacial erosional features. Data from both cosmogenic nuclides are in overall good agreement with each other confirming continuous exposure of the Gotthard Pass area throughout the Holocene. Some slightly younger in situ 14C ages compared to the corresponding 10Be ages are interpreted to result from partial surface shielding due to snow cover. Constraining the average Holocene snow depth from the in situ 14C data allowed to apply an appropriate snow shielding correction for the 10Be exposure ages. Integration of the snow-corrected exposure ages with field observations provided a detailed chronology of a progressive downwasting of ice from the maximum LGM ice volume with a gradual reorganization of the ice flow pattern and a southward migration of the ice divide. In a study on the evolution and reorganization of ice streams entering the Weddell Sea, Antarctica, during the last deglaciation, ice sheet modelling was

  18. Children's exposure to intimate partner violence: A meta-analysis of longitudinal associations with child adjustment problems.

    PubMed

    Vu, Nicole L; Jouriles, Ernest N; McDonald, Renee; Rosenfield, David

    2016-06-01

    This meta-analysis reviewed 74 studies that examined longitudinal associations between children's exposure to intimate partner violence (IPV) and their adjustment problems. Results indicated that children's exposure to IPV is linked prospectively with child externalizing, internalizing, and total adjustment problems. Moreover, the magnitude of the association between IPV exposure and child externalizing and internalizing problems strengthens over time. In addition, associations are stronger between IPV exposure and child externalizing and internalizing problems when IPV is conceptualized broadly rather than narrowly (physical IPV+psychological and/or sexual IPV versus physical IPV only), and when information on IPV and child adjustment problems is obtained from the same source, rather than independent sources. When IPV exposure is measured at younger ages, compared to older ages, the association between IPV and child externalizing problems is greater. However, when child adjustment problems are measured at older ages, compared to younger ages, the association between IPV and child internalizing problems is greater. Child sex, sample type, and whether only the male partner's violence or both partners' violence was measured did not predict the association between children's exposure to IPV and later adjustment problems. The findings have both research and clinical implications regarding the long-term adjustment of children exposed to IPV and the conceptualization and measurement of resilience subsequent to IPV.

  19. Gene expression analysis in gonads and brain of catfish Clarias batrachus after the exposure of malathion.

    PubMed

    Prathibha, Y; Murugananthkumar, R; Rajakumar, A; Laldinsangi, C; Sudhakumari, C C; Mamta, S K; Dutta-Gupta, A; Senthilkumaran, B

    2014-04-01

    Pesticides like malathion have the potential to disrupt development and reproduction of aquatic organisms including fishes. To investigate the likely consequences of malathion exposure at low doses in juvenile catfish, Clarias batrachus, we studied the expression pattern of genes encoding certain transcription factors, activin A, sex steroid or orphan nuclear receptors and steroidogenic enzymes which are known to be involved in gonadal development along with histological changes. To compare further, we also analyzed certain brain specific genes related to gonadal axis. Fifty days post hatch catfish fingerlings were exposed continuously to 1 and 10 µg/L of malathion for 21 days. Results from these experiments indicated that transcript levels of various genes were altered by the treatments, which may further affect the gonadal development either directly or indirectly through brain. Histological analysis revealed slow progression of spermatogenesis in testis, while in ovary, the oil droplet oocytes were found to be higher after treatment (10 µg/L). Our findings revealed that the exposure of malathion, even at low doses, hinder or modulate early gonadal development differentially by targeting gene expression pattern of transcription factors, activin A, sex steroid or orphan nuclear receptors and steroidogenic enzymes with an evidence on histological changes. Further, some of the genes showed differential expression at the level of brain in male and female sex after the exposure of malathion.

  20. A comparative study of human levels of trichloroethylene and tetrachloroethylene after occupational exposure

    SciTech Connect

    Skender, L.J.; Karacic, V.; Prpic-Majic, D. )

    1991-05-01

    The rate of trichloroethylene (TRI) and perchloroethylene (PER) absorption was investigated in workers who were (1) occupationally exposed to TRI in four dry-cleaning shops (Group 1, n = 10) and (2) occupationally exposed to PER in one dry-cleaning shop (Group 2, n = 18). Concentrations of TRI and PER in blood were analyzed, and concentrations of trichloroethanol (TCE) and trichloroacetic acid (TCA) in blood and urine were analyzed. Results varied widely: PER was found in the blood of workers in group 1, but TRI was not detected in blood from any worker in group 2; most blood samples from group 2 workers did not contain a detectable quantity of TCE, and urine TCE concentrations in this group were very low. During the work week, a significant difference was found in group 1 for TRI in blood and TCE in blood and urine. In group 2, however, the only significant difference during the work week was for PER in blood. Therefore, the most reliable biological indicators for TRI and PER exposure are TCE in blood and PER in blood, respectively.

  1. Comparison of discriminant analysis methods: Application to occupational exposure to particulate matter

    NASA Astrophysics Data System (ADS)

    Ramos, M. Rosário; Carolino, E.; Viegas, Carla; Viegas, Sandra

    2016-06-01

    Health effects associated with occupational exposure to particulate matter have been studied by several authors. In this study were selected six industries of five different areas: Cork company 1, Cork company 2, poultry, slaughterhouse for cattle, riding arena and production of animal feed. The measurements tool was a portable device for direct reading. This tool provides information on the particle number concentration for six different diameters, namely 0.3 µm, 0.5 µm, 1 µm, 2.5 µm, 5 µm and 10 µm. The focus on these features is because they might be more closely related with adverse health effects. The aim is to identify the particles that better discriminate the industries, with the ultimate goal of classifying industries regarding potential negative effects on workers' health. Several methods of discriminant analysis were applied to data of occupational exposure to particulate matter and compared with respect to classification accuracy. The selected methods were linear discriminant analyses (LDA); linear quadratic discriminant analysis (QDA), robust linear discriminant analysis with selected estimators (MLE (Maximum Likelihood Estimators), MVE (Minimum Volume Elipsoid), "t", MCD (Minimum Covariance Determinant), MCD-A, MCD-B), multinomial logistic regression and artificial neural networks (ANN). The predictive accuracy of the methods was accessed through a simulation study. ANN yielded the highest rate of classification accuracy in the data set under study. Results indicate that the particle number concentration of diameter size 0.5 µm is the parameter that better discriminates industries.

  2. Advanced Exposure Metrics For Chemical Risk Analysis: Systems Biology and 'Omic-based Biomarkers for Exposure Reconstruction

    EPA Science Inventory

    Direct measurement of human exposure to environmental contaminants in real time (when the exposure is actually occurring) is rare and difficult to obtain. This frustrates both exposure assessments and investigations into the linkage between chemical exposure and human disease. ...

  3. A Comparative Analysis of Charter Schools and Traditional Public Schools

    ERIC Educational Resources Information Center

    Smith, Jodi Renee Abbott

    2014-01-01

    The focus of this descriptive research study was to compare charter and traditional public schools on the academic knowledge of fifth grade students as measured by Arizona's Instrument to Measure Standards (AIMS) in a suburb of a large southwestern city. This analysis also compared charter and traditional public schools on AYP status. It was…

  4. A multiple additive regression tree analysis of three exposure measures during Hurricane Katrina.

    PubMed

    Curtis, Andrew; Li, Bin; Marx, Brian D; Mills, Jacqueline W; Pine, John

    2011-01-01

    This paper analyses structural and personal exposure to Hurricane Katrina. Structural exposure is measured by flood height and building damage; personal exposure is measured by the locations of 911 calls made during the response. Using these variables, this paper characterises the geography of exposure and also demonstrates the utility of a robust analytical approach in understanding health-related challenges to disadvantaged populations during recovery. Analysis is conducted using a contemporary statistical approach, a multiple additive regression tree (MART), which displays considerable improvement over traditional regression analysis. By using MART, the percentage of improvement in R-squares over standard multiple linear regression ranges from about 62 to more than 100 per cent. The most revealing finding is the modelled verification that African Americans experienced disproportionate exposure in both structural and personal contexts. Given the impact of exposure to health outcomes, this finding has implications for understanding the long-term health challenges facing this population.

  5. The Constant Comparative Analysis Method Outside of Grounded Theory

    ERIC Educational Resources Information Center

    Fram, Sheila M.

    2013-01-01

    This commentary addresses the gap in the literature regarding discussion of the legitimate use of Constant Comparative Analysis Method (CCA) outside of Grounded Theory. The purpose is to show the strength of using CCA to maintain the emic perspective and how theoretical frameworks can maintain the etic perspective throughout the analysis. My…

  6. Comparative carcinogenicity of the PAHs as a basis for acceptable exposure levels (AELs) in drinking water

    SciTech Connect

    Rugen, P.J.; Stern, C.D.; Lamm, S.H. )

    1989-06-01

    The carcinogenicity of various polynuclear aromatic hydrocarbons (PAHs) has generally been demonstrated by their ability to act as complete carcinogens in the development of cancers in rodent skin tests. In order to develop proposed acceptable concentration levels for various PAHs in drinking water, we reviewed the studies that formed the basis for determining that these specific PAHs were carcinogenic in animals. We found that the relative potency of these PAHs varied over a range of many orders of magnitude. For example, the carcinogenic strength of benz(a)anthracene (BaA) is found to be about 1/2000th that of benzo(a)pyrene (BaP). We have used the calculated carcinogenic potency of the various PAHs relative to that of BaP as a means for proposing specific acceptable concentration levels in drinking water for each of the specific PAHs. BaP is the only carcinogenic PAH for which EPA has published an acceptable concentration level based on carcinogenicity. Based on the level EPA set for BaP (0.028 micrograms/liter), this methodology has provided for the specific PAHs a determination of proposed acceptable concentration levels quantitatively based on the same data that were used to qualitatively determine them to be animal carcinogens. We have proposed acceptable concentration levels for the carcinogenic PAHs in drinking water that range from 0.03 micrograms/liter for BaP to 6.5 micrograms/liter for BaA. We recommend that acceptable concentration levels for the various PAHs be based on their relative carcinogenic potencies rather than the EPA method of using the potency of only one specific PAH, BaP, to serve as the exposure level determinant for all PAHs. We further suggest that this methodology may be applicable to other classes of carcinogenic compounds.

  7. Abbreviated environmental enrichment enhances neurobehavioral recovery comparably to continuous exposure after traumatic brain injury

    PubMed Central

    de Witt, Benjamin Wells; Ehrenberg, Kathryn M.; McAloon, Rose L.; Panos, Amanda H.; Shaw, Kaitlyn E.; Raghavan, Priya V.; Skidmore, Elizabeth R.; Kline, Anthony E.

    2011-01-01

    Background Environmental enrichment (EE) is a complex living milieu that has been shown to enhance functional recovery vs. standard (STD) housing after experimental traumatic brain injury (TBI) and therefore may be considered a rodent correlate of rehabilitation. However, the typical EE paradigm consists of continuous exposure to enrichment after TBI, which is inconsistent with the limited time frame in clinical rehabilitation. Objective To determine whether abbreviated EE (i.e., rehabilitation-relevant dose response) confers benefits similar to typical EE after TBI. Methods Adult male rats received either a controlled cortical impact (2.8 mm depth at 4 m/sec) or sham injury and were then randomly assigned to TBI + EE, TBI + EE (2hr), TBI + EE (4hr), TBI + EE (6hr), TBI + STD, and respective sham controls. Motor (beam-balance/beam-walk; BB/BW) and cognitive (Morris water maze; MWM) performance was assessed on post-operative days 1-5 and 14-19, respectively. Results The TBI + EE (2hr) and TBI + EE (4hr) groups were not statistically different from the TBI + STD group in any behavioral assessment. In contrast, the TBI + EE (6hr) group exhibited significant enhancement of motor and cognitive performance vs. the TBI + STD group, as well as the TBI + EE (2hr) and TBI + EE (4hr) groups (p < 0.003), and did not differ from the TBI + EE (typical) group. Conclusions These data demonstrate that abbreviated EE (6hr) produces motor and cognitive benefits similar to continuous EE after TBI and thus may be considered a dose-relevant rehabilitation paradigm. PMID:21186330

  8. Comparing the Novel Method of Assessing PrEP Adherence/Exposure Using Hair Samples to Other Pharmacologic and Traditional Measures

    PubMed Central

    Baxi, Sanjiv M.; Liu, Albert; Bacchetti, Peter; Mutua, Gaudensia; Sanders, Eduard J.; Kibengo, Freddie M.; Haberer, Jessica E.; Rooney, James; Hendrix, Craig W.; Anderson, Peter L.; Huang, Yong; Priddy, Frances

    2015-01-01

    Objective: The efficacy of pre-exposure prophylaxis (PrEP) in HIV will diminish with poor adherence; pharmacologic measures of drug exposure have proven critical to PrEP trial interpretation. We assessed drug exposure in hair against other pharmacologic and more routinely used measures to assess pill-taking. Design: Participants were randomized to placebo, daily PrEP, or intermittent PrEP to evaluate safety and tolerability of daily versus intermittent tenofovir/emtricitabine (TFV/FTC) in 2 phase II PrEP clinical trials conducted in Africa. Different measures of drug exposure, including self-report, medication event monitoring system (MEMS)-caps openings, and TFV/FTC levels in hair and other biomatrices were compared. Methods: At weeks 8 and 16, self-reported pill-taking, MEMS-caps openings, and TFV/FTC levels in hair, plasma, and peripheral blood mononuclear cells (PBMCs) were measured. Regression models evaluated predictors of TFV/FTC concentrations in the 3 biomatrices; correlation coefficients between pharmacologic and nonpharmacologic measures were calculated. Both trials were registered on ClinicalTrials.gov (NCT00931346/NCT00971230). Results: Hair collection was highly feasible and acceptable (100% in week 8; 96% in week 16). In multivariate analysis, strong associations were seen between pharmacologic measures and MEMS-caps openings (all P < 0.001); self-report was only weakly associated with pharmacologic measures. TFV/FTC hair concentrations were significantly correlated with levels in plasma and PBMCs (correlation coefficients, 0.41–0.86, all P < 0.001). Conclusions: Measuring TFV/FTC exposure in small hair samples in African PrEP trials was feasible and acceptable. Hair levels correlated strongly with PBMC, plasma concentrations, and MEMS-caps openings. As in other PrEP trials, self-report was the weakest measure of exposure. Further study of hair TFV/FTC levels in PrEP trials and demonstration projects to assess adherence/exposure is warranted. PMID

  9. Compare ultrasound-mediated heating and cavitation between flowing polymer- and lipid-shelled microbubbles during focused ultrasound exposures.

    PubMed

    Zhang, Siyuan; Zong, Yujin; Wan, Mingxi; Yu, Xiaojun; Fu, Quanyou; Ding, Ting; Zhou, Fanyu; Wang, Supin

    2012-06-01

    This paper compares the efficiency of flowing polymer- and lipid-shelled microbubbles (MBs) in the heating and cavitation during focused ultrasound exposures. Temperature and cavitation activity were simultaneously measured as the two types of shelled MBs and saline flowing through a 3 mm diameter vessel in the phantom with varying flow velocities (0-20 cm/s) at different acoustic power levels (0.6-20 W) with each exposure for 5 s. Temperature and cavitation for the lipid-shelled MBs were higher than those for the polymer-shelled MBs. Temperature rise decreased with increasing flow velocities for the two types of shelled MBs and saline at acoustic power 1.5 W. At acoustic power 11.1 W, temperature rise increased with increasing flow velocities for the lipid-shelled MBs. For the polymer-shelled MBs, the temperature rise increased with increasing flow velocities from 3-15 cm/s and decreased at 20 cm/s. Cavitation increased with increasing flow velocity for the two shelled MBs and there were no significant changes of cavitation with increasing flow velocities for saline. These results suggested that lipid-shelled MBs may have a greater efficiency than polymer-shelled MBs in heating and cavitation during focused ultrasound exposures.

  10. Comparative susceptibility of Atlantic salmon, lake trout and rainbow trout to Myxobolus cerebralis in controlled laboratory exposures

    USGS Publications Warehouse

    Blazer, V.S.; Densmore, Christine L.; Schill, W.B.; Cartwright, Deborah D.; Page, S.J.

    2004-01-01

    The susceptibility of lake trout Salvelinus namaycush, rainbow trout Oncorhynchus mykiss and Atlantic salmon Salmo salar to Myxobolus cerebralis, the causative agent of whirling disease, was compared in controlled laboratory exposures. A total of 450 (225 for each dose) fry for each species were exposed to a low (200 spores per fish) or high (2000 spores per fish) dose of the infective triactinomyxon. At 22 wk post-exposure, 60 fish from each group, as well as controls for each species, were examined for clinical signs (whirling behavior, blacktail, deformed heads and skeletal deformities), microscopic lesions, and presence of spores. Rainbow trout were highly susceptible to infection, with 100% being positive for spores and with microscopic pathological changes in both exposure groups. Rainbow trout were the only species to show whirling behavior and blacktail. Atlantic salmon were less susceptible, with only 44 and 61% being positive for spores, respectively, in the low and high dose groups, while 68 and 75%, respectively, had microscopic pathology associated with cartilage damage. Rainbow trout heads contained mean spore concentrations of 2.2 (low dose) or 4.0 (high dose) ?? 106 spores g tissue-1. The means for positive Atlantic salmon (not including zero values) were 1.7 (low) and 7.4 (high) ?? 104 spores g tissue-1. Lake trout showed no clinical signs of infection, were negative for spores in both groups and showed no histopathological signs of M. cerebralis infection.

  11. Comparing changes in transient-evoked otoacoustic emission and pure-tone audiometry following short exposure to industrial noise.

    PubMed

    Slliwinska-Kowalska, Mariola; Kotylo, Piotr; Hendler, Beata

    1999-01-01

    It has been suggested that otoacoustic emissions, particularly transient-evoked otoacoustic emissions (TEOAE), might be more sensitive in assessment of changes to the cochlea caused by noise than pure-tone audiometry (PTA). The aim of the study was to compare temporary threshold shifts with the changes in TEOAE following a six-hour exposure to industrial noise at the intensity of 85-97 dB (A). Thirty two male employees of a metal factory were screened. TEOAE, PTA and tympanometry were included in the hearing test battery. Both, PTA and TEOAE showed significant reduction due to noise exposure, but no correlation between temporary threshold shifts and decreases in either the overall TOAE level or the level of otoacoustic emission in the frequency bands was found. Our results confirm the high sensitivity of TEOAE to short exposure to industrial noise. This study may recommend this measurement as a method of evaluation for TTS conditions for hearing conservation programme purposes, in addition to pure-tone audiometry.

  12. Renal Effects and Carcinogenicity of Occupational Exposure to Uranium: A Meta-Analysis

    PubMed Central

    Stammler, Leonhard; Uhl, Andreas; Mayer, Benjamin; Keller, Frieder

    2016-01-01

    Purpose Uranium is a heavy metal with alpha radioactivity. We state the hypothesis that uranium exposure is harmful to human kidneys and carcinogenic to body tissues. Therefore, we review epidemiological studies from people with known long-lasting uranium exposure. Materials and Methods Three meta-analyses are performed using clinical studies published in the PubMed database and applying RevMan 5.3 from the Cochrane Collaboration to calculate the outcome. The first two meta-analyses examine the standardized mortality ratio (SMR) and the standardized incidence ratio for any cancers of uranium workers who were operating in areas ranging from uranium processing to the assembly of final uranium products. The third meta-analysis evaluates the nephrotoxic risk in uranium workers as well as soldiers and of individuals with exposure to drinking water containing uranium. Results Overall and contrasting to our hypothesis, the tumor risk is significantly lower for uranium workers than for control groups (SMR = 0.90 with a 95% confidence interval of 0.84 to 0.96). In addition and also contrasting to our hypothesis, the risk of nephrotoxicity is not increased either. This holds for both the incidence and the mortality due to renal cell carcinoma or due to acute kidney injury or chronic kidney disease. In contrast, a significantly better creatinine clearance is found for the uranium cohort as compared to the control groups (mean difference = 7.66 with a 95% confidence interval of 0.12 to 15.2). Conclusion Our hypothesis that a chronic uranium exposure is associated with an increased risk of cancer mortality or of kidney failure is refuted by clinical data. The decreased risk may result from better medical surveillance of uranium workers. PMID:27275162

  13. Pesticide Flow Analysis to Assess Human Exposure in Greenhouse Flower Production in Colombia

    PubMed Central

    Lesmes-Fabian, Camilo; Binder, Claudia R.

    2013-01-01

    Human exposure assessment tools represent a means for understanding human exposure to pesticides in agricultural activities and managing possible health risks. This paper presents a pesticide flow analysis modeling approach developed to assess human exposure to pesticide use in greenhouse flower crops in Colombia, focusing on dermal and inhalation exposure. This approach is based on the material flow analysis methodology. The transfer coefficients were obtained using the whole body dosimetry method for dermal exposure and the button personal inhalable aerosol sampler for inhalation exposure, using the tracer uranine as a pesticide surrogate. The case study was a greenhouse rose farm in the Bogota Plateau in Colombia. The approach was applied to estimate the exposure to pesticides such as mancozeb, carbendazim, propamocarb hydrochloride, fosetyl, carboxin, thiram, dimethomorph and mandipropamide. We found dermal absorption estimations close to the AOEL reference values for the pesticides carbendazim, mancozeb, thiram and mandipropamide during the study period. In addition, high values of dermal exposure were found on the forearms, hands, chest and legs of study participants, indicating weaknesses in the overlapping areas of the personal protective equipment parts. These results show how the material flow analysis methodology can be applied in the field of human exposure for early recognition of the dispersion of pesticides and support the development of measures to improve operational safety during pesticide management. Furthermore, the model makes it possible to identify the status quo of the health risk faced by workers in the study area. PMID:23528812

  14. Pesticide flow analysis to assess human exposure in greenhouse flower production in Colombia.

    PubMed

    Lesmes-Fabian, Camilo; Binder, Claudia R

    2013-03-25

    Human exposure assessment tools represent a means for understanding human exposure to pesticides in agricultural activities and managing possible health risks. This paper presents a pesticide flow analysis modeling approach developed to assess human exposure to pesticide use in greenhouse flower crops in Colombia, focusing on dermal and inhalation exposure. This approach is based on the material flow analysis methodology. The transfer coefficients were obtained using the whole body dosimetry method for dermal exposure and the button personal inhalable aerosol sampler for inhalation exposure, using the tracer uranine as a pesticide surrogate. The case study was a greenhouse rose farm in the Bogota Plateau in Colombia. The approach was applied to estimate the exposure to pesticides such as mancozeb, carbendazim, propamocarb hydrochloride, fosetyl, carboxin, thiram, dimethomorph and mandipropamide. We found dermal absorption estimations close to the AOEL reference values for the pesticides carbendazim, mancozeb, thiram and mandipropamide during the study period. In addition, high values of dermal exposure were found on the forearms, hands, chest and legs of study participants, indicating weaknesses in the overlapping areas of the personal protective equipment parts. These results show how the material flow analysis methodology can be applied in the field of human exposure for early recognition of the dispersion of pesticides and support the development of measures to improve operational safety during pesticide management. Furthermore, the model makes it possible to identify the status quo of the health risk faced by workers in the study area.

  15. Toxicokinetics of perfluorooctane sulfonate in rabbits under environmentally realistic exposure conditions and comparative assessment between mammals and birds.

    PubMed

    Tarazona, J V; Rodríguez, C; Alonso, E; Sáez, M; González, F; San Andrés, M D; Jiménez, B; San Andrés, M I

    2016-01-22

    This article describes the toxicokinetics of perfluorooctane sulfonate (PFOS) in rabbits under low repeated dosing, equivalent to 0.085μg/kg per day, and the observed differences between rabbits and chickens. The best fitting for both species was provided by a simple pseudo monocompartmental first-order kinetics model, regulated by two rates, and accounting for real elimination as well as binding of PFOS to non-exchangeable structures. Elimination was more rapid in rabbits, with a pseudo first-order dissipation half-life of 88 days compared to the 230 days observed for chickens. By contrast, the calculated assimilation efficiency for rabbits was almost 1, very close to full absorption, significantly higher than the 0.66 with confidence intervals of 0.64 and 0.68 observed for chickens. The results confirm a very different kinetics than that observed in single-dose experiments confirming clear dose-related differences in apparent elimination rates in rabbits, as previously described for humans and other mammals; suggesting the role of a capacity-limited saturable process resulting in different kinetic behaviours for PFOS in high dose versus environmentally relevant low dose exposure conditions. The model calculations confirmed that the measured maximum concentrations were still far from the steady state situation, and that the different kinetics between birds and mammals should may play a significant role in the biomagnifications assessment and potential exposure for humans and predators. For the same dose regime, the steady state concentration was estimated at about 36μg PFOS/L serum for rabbits, slightly above one-half of the 65μg PFOS/L serum estimated for chickens. The toxicokinetic parameters presented here can be used for higher-tier bioaccumulation estimations of PFOS in rabbits and chickens as starting point for human health exposure assessments and as surrogate values for modeling PFOS kinetics in wild mammals and bird in exposure assessment of predatory

  16. Malignant mesothelioma not related to asbestos exposure: Analytical scanning electron microscopic analysis of 83 cases and comparison with 442 asbestos-related cases.

    PubMed

    Kraynie, Alyssa; de Ridder, Gustaaf G; Sporn, Thomas A; Pavlisko, Elizabeth N; Roggli, Victor L

    2016-01-01

    Epidemiological studies indicate that 80-90% of mesotheliomas are asbestos related. This suggests that 10-20% are not. Lung fiber burden analysis provides objective information about past exposures to asbestos. We have performed lung fiber burden analysis on a large cohort of mesothelioma cases and compared the findings with a reference population. Herein we report our findings along with demographic and exposure data.

  17. Causal Analysis of the Unanticipated Extremity Exposure at HFEF

    SciTech Connect

    David E. James; Charles R. Posegate; Thomas P. Zahn; Alan G. Wagner

    2011-11-01

    This report covers the unintended extremity exposure to an operator while handling a metallurgical mount sample of irradiated fuel following an off-scale high beta radiation reading of the sample. The decision was made to continue working after the meter indicated high off-scale by the HPT Supervisor, which resulted in the operator at the next operation being exposed.

  18. Behavioral Outcomes of Young Children with Prenatal Exposure to Alcohol: Review and Analysis of Experimental Literature.

    ERIC Educational Resources Information Center

    Williams, Rosanne C.; Carta, Judith J.

    1996-01-01

    Analysis of 51 studies of developmental effects of prenatal exposure to alcohol in children from birth to 72 months found that, although adverse outcomes were found within each domain, age grouping, and exposure category, they comprised fewer than 50% of all outcomes measured. Most adverse outcomes were found in the neurobehavioral domain with…

  19. 77 FR 37717 - Electrical Cable Test Results and Analysis During Fire Exposure

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-22

    ... COMMISSION Electrical Cable Test Results and Analysis During Fire Exposure AGENCY: Nuclear Regulatory... during Fire Exposure (ELECTRA-FIRE), A Consolidation of the Three Major Fire-Induced Circuit and Cable... conducted to realistically explore the electrical functionality of electrical cables under severe...

  20. Simulation study comparing exposure matching with regression adjustment in an observational safety setting with group sequential monitoring.

    PubMed

    Stratton, Kelly G; Cook, Andrea J; Jackson, Lisa A; Nelson, Jennifer C

    2015-03-30

    Sequential methods are well established for randomized clinical trials (RCTs), and their use in observational settings has increased with the development of national vaccine and drug safety surveillance systems that monitor large healthcare databases. Observational safety monitoring requires that sequential testing methods be better equipped to incorporate confounder adjustment and accommodate rare adverse events. New methods designed specifically for observational surveillance include a group sequential likelihood ratio test that uses exposure matching and generalized estimating equations approach that involves regression adjustment. However, little is known about the statistical performance of these methods or how they compare to RCT methods in both observational and rare outcome settings. We conducted a simulation study to determine the type I error, power and time-to-surveillance-end of group sequential likelihood ratio test, generalized estimating equations and RCT methods that construct group sequential Lan-DeMets boundaries using data from a matched (group sequential Lan-DeMets-matching) or unmatched regression (group sequential Lan-DeMets-regression) setting. We also compared the methods using data from a multisite vaccine safety study. All methods had acceptable type I error, but regression methods were more powerful, faster at detecting true safety signals and less prone to implementation difficulties with rare events than exposure matching methods. Method performance also depended on the distribution of information and extent of confounding by site. Our results suggest that choice of sequential method, especially the confounder control strategy, is critical in rare event observational settings. These findings provide guidance for choosing methods in this context and, in particular, suggest caution when conducting exposure matching.

  1. Comparative Study on Countermeasures for Health Risk through Exposure to Asbestos

    NASA Astrophysics Data System (ADS)

    Fujinaga, Aiichiro; Sasamoto, Yuzuru; Yoshida, Koji

    This study examines countermeasures against asbestos by predicting air concentrations of asbestos in order to reduce health risk of asbestos from demolishing buildings and other processes. A comparative study was conducted on three cases as follows; Case 1 was "No action", Case 2 was "Demolishing by hand", and Case 3 was "Vitrification treatment". The result showed that the health risk from Case 2 is 20% less risky than Case 1, if Case 2 is accomplished perfectly. More desirably, the health risk from Case 3 is 30% less risky than Case 1. In addition, " No action " takes the longest time to achieve risk reduction. However, Case 2 and Case 3 can greatly reduce the time needed. Therefore, this study indicates that "Demolishing by hand" should be conducted first. If it is not possible to conduct perfectly, "Vitrification" can be applied even though the cost is high.

  2. Comparative analysis of genomic signal processing for microarray data clustering.

    PubMed

    Istepanian, Robert S H; Sungoor, Ala; Nebel, Jean-Christophe

    2011-12-01

    Genomic signal processing is a new area of research that combines advanced digital signal processing methodologies for enhanced genetic data analysis. It has many promising applications in bioinformatics and next generation of healthcare systems, in particular, in the field of microarray data clustering. In this paper we present a comparative performance analysis of enhanced digital spectral analysis methods for robust clustering of gene expression across multiple microarray data samples. Three digital signal processing methods: linear predictive coding, wavelet decomposition, and fractal dimension are studied to provide a comparative evaluation of the clustering performance of these methods on several microarray datasets. The results of this study show that the fractal approach provides the best clustering accuracy compared to other digital signal processing and well known statistical methods.

  3. Correlating radiation exposure with embrittlement: Comparative studies of electron- and neutron-irradiated pressure vessel alloys

    SciTech Connect

    Alexander, D. E.; Rehn, L. E.; Odette, G. R.; Lucas, G. E.; Klingensmith, D.; Gragg, D.

    1999-12-22

    Comparative experiments using high energy (10 MeV) electrons and test reactor neutrons have been undertaken to understand the role that primary damage state has on hardening (embrittlement) induced by irradiation at 300 C. Electrons produce displacement damage primarily by low energy atomic recoils, while fast neutrons produce displacements from considerably higher energy recoils. Comparison of changes resulting from neutron irradiation, in which nascent point defect clusters can form in dense cascades, with electron irradiation, where cascade formation is minimized, can provide insight into the role that the in-cascade point defect clusters have on the mechanisms of embrittlement. Tensile property changes induced by 10 MeV electrons or test reactor neutron irradiations of unalloyed iron and an Fe-O.9 wt.% Cu-1.0 wt.% Mn alloy were examined in the damage range of 9.0 x 10{sup {minus}5} dpa to 1.5 x 10{sup {minus}2} dpa. The results show the ternary alloy experienced substantially greater embrittlement in both the electron and neutron irradiate samples relative to unalloyed iron. Despite their disparate nature of defect production similar embrittlement trends with increasing radiation damage were observed for electrons and neutrons in both the ternary and unalloyed iron.

  4. Proteomic analysis of adducted butyrylcholinesterase for biomonitoring organophosphorus exposures

    PubMed Central

    Marsillach, Judit; Hsieh, Edward J.; Richter, Rebecca J.; MacCoss, Michael J.; Furlong, Clement E.

    2014-01-01

    Organophosphorus (OP) compounds include a broad group of toxic chemicals such as insecticides, chemical warfare agents and antiwear agents. The liver cytochromes P450 bioactivate many OPs to potent inhibitors of serine hydrolases. Cholinesterases were the first OP targets discovered and are the most studied. They are used to monitor human exposures to OP compounds. However, the assay that is currently used has limitations. The mechanism of action of OP compounds is the inhibition of serine hydrolases by covalently modifying their active-site serine. After structural rearrangement, the complex OP inhibitor-enzyme is irreversible and will remain in circulation until the modified enzyme is degraded. Mass spectrometry is a sensitive technology for analyzing protein modifications, such as OP-adducted enzymes. These analyses also provide some information about the nature of the OP adduct. Our aim is to develop high-throughput protocols for monitoring OP exposures using mass spectrometry. PMID:23123252

  5. Laser exposure analysis for a near-infrared ocular interferometer

    NASA Astrophysics Data System (ADS)

    Primeau, Brian C.; Goldstein, Goldie L.; Greivenkamp, John E.

    2012-06-01

    Ocular interferometry has potential value in a variety of ocular measurement applications, including measuring ocular thicknesses, topography of ocular surfaces or the wavefront of the eye. Of particular interest is using interferometry for characterizing corneal shape and irregular corneal features, making this technology attractive due to its inherent accuracy and spatial resolution. A particular challenge of designing an ocular interferometer is determining safe laser exposure levels to the eye, including both the retina and anterior segment. Described here are the laser exposure standards relevant in the interferometer design and the corresponding calculations and results. The results of this work can be used to aid in the design of similar laser-based systems for ocular evaluation.

  6. Methylmercury exposure and mortality in Japan: a life table analysis

    SciTech Connect

    Tamashiro, H.; Fukutomi, K.; Lee, E.S.

    1987-03-01

    The effects on life expectancy from elevated methylmercury (MeHg) exposure were studied in five coastal towns of southern Japan. Hair concentrations of MeHg in the study area were 3 to 6 times higher than the surrounding areas. From 1969-1972 to 1978-1982 life expectancy increased in the study area, with no appreciable difference between that area and the two control areas. When four major causes of death were deleted analytically in both study and control areas, malignant neoplasms contributed the most in recent years to potential gains in life expectancy for both sexes. For the duration of their working ages, however, accidents were the leading contributor for males, followed by malignant neoplasms, heart disease, and cerebrovascular disease. The relative contribution of these causes of death to gain in life expectancy in the study area population is discussed in the context of elevated MeHg exposure.

  7. Exposure-response analysis of cancer mortality in a cohort of workers exposed to ethylene oxide.

    PubMed

    Stayner, L; Steenland, K; Greife, A; Hornung, R; Hayes, R B; Nowlin, S; Morawetz, J; Ringenburg, V; Elliot, L; Halperin, W

    1993-11-15

    The authors previously reported results from the largest cohort mortality study of ethylene oxide-exposed workers that has been conducted to date. Here they extend their previous work by quantitatively examining the relation between cancer mortality and ethylene oxide exposure. This study included workers from 13 of the 14 geographically distinct facilities that were included in the previous investigation. These facilities began regularly using ethylene oxide to sterilize medical supplies or spices sometime between 1938 and 1969. Workers were followed from first exposure through December 31, 1987. Historical exposures to ethylene oxide were estimated using a regression model. Standard life-table analysis was used to examine cancer mortality in three categories of cumulative exposure to ethylene oxide. The Cox proportional hazards model was also used to examine cumulative and other measures of ethylene oxide exposure as predictors of cancer mortality. In both the life-table analysis and the Cox model, a positive trend was observed in all lymphatic and hematopoietic cancer mortality for cumulative ethylene oxide exposure. This trend was strengthened when ethylene oxide exposures 10 years prior to death were discounted (lagged) and when the analysis was restricted to neoplasms of lymphoid cell origin. Despite limitations discussed in this paper, the authors believe that these findings provide some support for the hypothesis that exposure to ethylene oxide increases the risk of mortality from lymphatic and hematopoietic neoplasms. The authors intend to continue follow-up of this relatively young cohort, which may allow more definitive conclusions to be drawn in the future.

  8. CRITICA: coding region identification tool invoking comparative analysis

    NASA Technical Reports Server (NTRS)

    Badger, J. H.; Olsen, G. J.; Woese, C. R. (Principal Investigator)

    1999-01-01

    Gene recognition is essential to understanding existing and future DNA sequence data. CRITICA (Coding Region Identification Tool Invoking Comparative Analysis) is a suite of programs for identifying likely protein-coding sequences in DNA by combining comparative analysis of DNA sequences with more common noncomparative methods. In the comparative component of the analysis, regions of DNA are aligned with related sequences from the DNA databases; if the translation of the aligned sequences has greater amino acid identity than expected for the observed percentage nucleotide identity, this is interpreted as evidence for coding. CRITICA also incorporates noncomparative information derived from the relative frequencies of hexanucleotides in coding frames versus other contexts (i.e., dicodon bias). The dicodon usage information is derived by iterative analysis of the data, such that CRITICA is not dependent on the existence or accuracy of coding sequence annotations in the databases. This independence makes the method particularly well suited for the analysis of novel genomes. CRITICA was tested by analyzing the available Salmonella typhimurium DNA sequences. Its predictions were compared with the DNA sequence annotations and with the predictions of GenMark. CRITICA proved to be more accurate than GenMark, and moreover, many of its predictions that would seem to be errors instead reflect problems in the sequence databases. The source code of CRITICA is freely available by anonymous FTP (rdp.life.uiuc.edu in/pub/critica) and on the World Wide Web (http:/(/)rdpwww.life.uiuc.edu).

  9. World Trade Center disaster exposure-related probable posttraumatic stress disorder among responders and civilians: a meta-analysis.

    PubMed

    Liu, Bian; Tarigan, Lukman H; Bromet, Evelyn J; Kim, Hyun

    2014-01-01

    The World Trade Center (WTC) disaster on September 11, 2001 was an unprecedented traumatic event with long-lasting health consequences among the affected populations in the New York metropolitan area. This meta-analysis aimed to estimate the risk of probable posttraumatic stress disorder (PTSD) associated with specific types of WTC exposures. Meta-analytical findings from 10 studies of 3,271 to 20,294 participants yielded 37 relevant associations. The pooled summary odds ratio (OR) was 2.05 (95% confidence interval (CI): 1.82, 2.32), with substantial heterogeneity linked to exposure classification, cohort type, data source, PTSD assessment instrument/criteria, and lapse time since 9/11. In general, responders (e.g. police, firefighters, rescue/recovery workers and volunteers) had a lower probable PTSD risk (OR = 1.61; 95% CI: 1.39, 1.87) compared to civilians (e.g. residents, office workers, and passersby; OR = 2.71, 95% CI: 2.35, 3.12). The differences in ORs between responders and civilians were larger for physical compared to psychosocial exposure types. We also found that injury, lost someone, and witnessed horror were the three (out of six) most pernicious exposures. These findings suggest that these three exposures should be a particular focus in psychological evaluation and treatment programs in WTC intervention and future emergency preparedness efforts.

  10. World Trade Center Disaster Exposure-Related Probable Posttraumatic Stress Disorder among Responders and Civilians: A Meta-Analysis

    PubMed Central

    Liu, Bian; Tarigan, Lukman H.; Bromet, Evelyn J.; Kim, Hyun

    2014-01-01

    The World Trade Center (WTC) disaster on September 11, 2001 was an unprecedented traumatic event with long-lasting health consequences among the affected populations in the New York metropolitan area. This meta-analysis aimed to estimate the risk of probable posttraumatic stress disorder (PTSD) associated with specific types of WTC exposures. Meta-analytical findings from 10 studies of 3,271 to 20,294 participants yielded 37 relevant associations. The pooled summary odds ratio (OR) was 2.05 (95% confidence interval (CI): 1.82, 2.32), with substantial heterogeneity linked to exposure classification, cohort type, data source, PTSD assessment instrument/criteria, and lapse time since 9/11. In general, responders (e.g. police, firefighters, rescue/recovery workers and volunteers) had a lower probable PTSD risk (OR = 1.61; 95% CI: 1.39, 1.87) compared to civilians (e.g. residents, office workers, and passersby; OR = 2.71, 95% CI: 2.35, 3.12). The differences in ORs between responders and civilians were larger for physical compared to psychosocial exposure types. We also found that injury, lost someone, and witnessed horror were the three (out of six) most pernicious exposures. These findings suggest that these three exposures should be a particular focus in psychological evaluation and treatment programs in WTC intervention and future emergency preparedness efforts. PMID:25047411

  11. Computational Methods for the Analysis of Array Comparative Genomic Hybridization

    PubMed Central

    Chari, Raj; Lockwood, William W.; Lam, Wan L.

    2006-01-01

    Array comparative genomic hybridization (array CGH) is a technique for assaying the copy number status of cancer genomes. The widespread use of this technology has lead to a rapid accumulation of high throughput data, which in turn has prompted the development of computational strategies for the analysis of array CGH data. Here we explain the principles behind array image processing, data visualization and genomic profile analysis, review currently available software packages, and raise considerations for future software development. PMID:17992253

  12. Gap Analysis Comparing LLNL ISMS and ISO 14001

    SciTech Connect

    Doerr, T B

    2004-08-09

    A gap analysis was conducted comparing the Lawrence Livermore National Laboratory (LLNL) Integrated Safety Management System (ISMS) with the international standard ISO 14001 Environmental Management System and with Department of Energy (DOE) Order 450.1. This analysis was accomplished as part of LLNL's assessment of the impacts of adopting DOE Order 450.1 and comprises a portion of its continuous improvement efforts under ISMS.

  13. RECENT DEVELOPMENTS IN EXHALED BREATH ANALYSIS AND HUMAN EXPOSURE ASSESSMENT RESEARCH

    EPA Science Inventory

    This presentation will explore historical and newly emerging methods for the collection and analysis of exhaled breath for use in environmental exposure assessment studies. We will discuss their applicability and limitations with respect to environmental research. Particular em...

  14. UNCERTAINTY ANALYSIS OF TCE USING THE DOSE EXPOSURE ESTIMATING MODEL (DEEM) IN ACSL

    EPA Science Inventory

    The ACSL-based Dose Exposure Estimating Model(DEEM) under development by EPA is used to perform art uncertainty analysis of a physiologically based pharmacokinetic (PSPK) model of trichloroethylene (TCE). This model involves several circulating metabolites such as trichloroacet...

  15. Comparative toxicity of glyphosate-based herbicides: aqueous and sediment porewater exposures.

    PubMed

    Tsui, Martin T K; Chu, L M

    2004-04-01

    Glyphosate-based herbicides are widely used for aquatic weed control. However, their aquatic toxicity data, especially those on sediment, are relatively scarce. In this study, the water-only acute toxicity of three formulations based on glyphosate (Rodeo, Roundup Biactive, and Roundup) were compared using a water-column organism (cladoceran: Ceriodaphnia dubia) and a benthic organism (amphipod: Hyalella azteca). In addition, Roundup Biactive and Roundup were spiked into a clean sediment which was amended with appropriate amounts of peat moss to study the effect of different organic carbon levels (0, 0.4, 1.2, and 2.1%) on their sediment toxicity, with C. dubia exposed to overlying water or porewater prepared from the contaminated sediments. Results showed that the toxicity based on 48-h LC50s for the three herbicides in the water-only tests was Roundup (1.5-5.7 mg L(-1)) > Roundup Biactive (82-120 mg L(-1)) > Rodeo (225-415 mg L(-1)), and H. azteca was generally more sensitive than C. dubia to these herbicides. Toxicity differences between formulations were due to the different surfactant components in these herbicides. From the porewater toxicity tests, Roundup Biactive (340 mg kg(-1)) and Roundup (244 mg kg(-1)) were similarly toxic in the sediment tests at 0% organic carbon, indicating that the surfactants in Roundup were considerably more adsorptive than those in Roundup Biactive to the sediment of the same organic carbon. Also, an increase in organic carbon significantly decreased the toxicity of Roundup in sediment, but not for Roundup Biactive. Sediment-porewater partitioning of glyphosate was found to be influenced by sediment organic carbon (i.e., glyphosate adsorption increased with sediment organic carbon).

  16. Influence of Human Activity Patterns, particle composition, and residential air exchange rates on modeled distributions of PM 2.5 exposure compared with central-site monitoring data

    EPA Science Inventory

    Central-site monitors do not account for factors such as outdoor-to-indoor transport and human activity patterns that influence personal exposures to ambient fine-particulate matter (PM2.5). We describe and compare different ambient PM2.5 exposure estimation...

  17. Assessing population exposure for landslide risk analysis using dasymetric cartography

    NASA Astrophysics Data System (ADS)

    Garcia, Ricardo A. C.; Oliveira, Sérgio C.; Zêzere, José L.

    2016-12-01

    Assessing the number and locations of exposed people is a crucial step in landslide risk management and emergency planning. The available population statistical data frequently have insufficient detail for an accurate assessment of potentially exposed people to hazardous events, mainly when they occur at the local scale, such as with landslides. The present study aims to apply dasymetric cartography to improving population spatial resolution and to assess the potentially exposed population. An additional objective is to compare the results with those obtained with a more common approach that uses, as spatial units, basic census units, which are the best spatial data disaggregation and detailed information available for regional studies in Portugal. Considering the Portuguese census data and a layer of residential building footprint, which was used as ancillary information, the number of exposed inhabitants differs significantly according to the approach used. When the census unit approach is used, considering the three highest landslide susceptible classes, the number of exposed inhabitants is in general overestimated. Despite the associated uncertainties of a general cost-benefit analysis, the presented methodology seems to be a reliable approach for gaining a first approximation of a more detailed estimation of exposed people. The approach based on dasymetric cartography allows the spatial resolution of population over large areas to be increased and enables the use of detailed landslide susceptibility maps, which are valuable for improving the exposed population assessment.

  18. A Matched Analysis of Diabetes Mellitus and Herbicide Exposure in Veterans of Operation Ranch Hand

    DTIC Science & Technology

    2006-06-01

    AFRL-HE-BR-TR-2006-0016 Air Force Research Laboratory A MATCHED ANALYSIS OF DIABETES MELLITUS AND HERBICIDE EXPOSURE IN VETERANS OF OPERATION RANCH...TYPE 30-05-2001 Technical Report 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER N/A Matched Analysis of Diabetes Mellitus and Herbicide Exposure in Veterans...been artifactual. 15. SUBJECT TERMS Diabetes mellitus , Agent Orange, dioxin, Vietnam veterans, herbicides. 16. SECURITY CLASSIFICATION OF: 17

  19. Histomorphometric and proteomic analysis of the acute rabbit corneal tissue response following in vitro exposure to 1540-nm laser light

    NASA Astrophysics Data System (ADS)

    Eurell, Thomas E.; Johnson, Thomas E.; Roach, William P.

    2003-06-01

    In vitro exposures of explant rabbit corneas to single pulse 1540 nm infrared laser light operating at a pulse width of 0.8 milliseconds resulted in coagulative necrosis of both the corneal epithelium and stroma. Histomorphometric data correlated with increasing tissue radiant exposures. Histologic alterations in the corneal stroma were typical of matrix remodeling within the beam path and reactive to antibodies against matrix metalloproteinase-2. A two-dimensional electrophoretic analysis, using a mini-gel format, was developed to determine if specific corneal protein changes within tissue sections could be detected. Frozen sections taken through the center of the laser lesion were evaluated for proteomic data using tissue isoelectric focusing in the first dimension and polyacrylamide gel electrophoresis in the second dimension. Histomorphometric data describing the extent of the laser lesions were compared to the isoelectric points, molecular weights and relative densities of individual corneal proteins. Increasing radiant exposures of corneal tissues were associated with characteristic histomorphometric and proteomic changes.

  20. Micronuclei as biomarkers of carcinogen exposure in populations exposed to arsenic through drinking water in West Bengal, India: a comparative study in three cell types.

    PubMed

    Basu, Anamika; Ghosh, Pritha; Das, Jayanta K; Banerjee, Apurba; Ray, Kunal; Giri, Ashok K

    2004-05-01

    Contamination of groundwater by arsenic, a paradoxical human carcinogen, has become a cause of global public health concern. In West Bengal, India, the groundwater in 9 of 18 districts is heavily contaminated with arsenic. Various adverse health effects including cancer have been reported from these districts and are associated with prolonged arsenic exposure. A cross-sectional biomarker study was conducted to evaluate and compare the frequencies of micronuclei in peripheral blood lymphocytes, oral mucosa cells, and urothelial cells from the inhabitants of North 24 Parganas, one of the arsenic-affected districts. The three cell types were collected from 163 residents exposed to high levels of arsenic in drinking water (214.7213 +/- 9.0273 microg/l) and from 154 unexposed subjects residing in the unaffected East Midnapur district with very little or no exposure to arsenic through drinking water (9.2017 +/- 0.3157 microg/l). Our analysis revealed that micronuclei frequencies in the exposed group were significantly elevated to 5.33-fold over unexposed levels for lymphocytes, 4.63-fold for oral mucosa cells, and 4.71-fold for urothelial cells (increases in micronuclei frequencies significant at P < 0.01). The results indicate that chronic ingestion of arsenic in drinking water by the exposed subjects is linked to the enhanced incidence of micronuclei in all the three cell types, slightly higher level of micronuclei being observed in lymphocytes compared with oral mucosa and urothelial cells.

  1. Tools for comparative protein structure modeling and analysis.

    PubMed

    Eswar, Narayanan; John, Bino; Mirkovic, Nebojsa; Fiser, Andras; Ilyin, Valentin A; Pieper, Ursula; Stuart, Ashley C; Marti-Renom, Marc A; Madhusudhan, M S; Yerkovich, Bozidar; Sali, Andrej

    2003-07-01

    The following resources for comparative protein structure modeling and analysis are described (http://salilab.org): MODELLER, a program for comparative modeling by satisfaction of spatial restraints; MODWEB, a web server for automated comparative modeling that relies on PSI-BLAST, IMPALA and MODELLER; MODLOOP, a web server for automated loop modeling that relies on MODELLER; MOULDER, a CPU intensive protocol of MODWEB for building comparative models based on distant known structures; MODBASE, a comprehensive database of annotated comparative models for all sequences detectably related to a known structure; MODVIEW, a Netscape plugin for Linux that integrates viewing of multiple sequences and structures; and SNPWEB, a web server for structure-based prediction of the functional impact of a single amino acid substitution.

  2. Comparative and Familial Analysis of Handedness in Great Apes

    ERIC Educational Resources Information Center

    Hopkins, William D.

    2006-01-01

    Historically, population-level handedness has been considered a hallmark of human evolution. Whether nonhuman primates exhibit population-level handedness remains a topic of considerable debate. This paper summarizes published data on handedness in great apes. Comparative analysis indicated that chimpanzees and bonobos show population-level right…

  3. A Framework for the Comparative Analysis of Farm Organizations.

    ERIC Educational Resources Information Center

    Molnar, Joseph J.

    Presenting a model for the comparative analysis of farm organizations, this paper analyzes the farm firm as a complex organization; identifies key structural dimensions of an agricultural production unit; and reviews various organizational perspectives for their utility in understanding and explaining the behavior of farm operations and farm…

  4. A Comparative Analysis of Three Unique Theories of Organizational Learning

    ERIC Educational Resources Information Center

    Leavitt, Carol C.

    2011-01-01

    The purpose of this paper is to present three classical theories on organizational learning and conduct a comparative analysis that highlights their strengths, similarities, and differences. Two of the theories -- experiential learning theory and adaptive -- generative learning theory -- represent the thinking of the cognitive perspective, while…

  5. Not later, but longer: sleep, chronotype and light exposure in adolescents with remitted depression compared to healthy controls.

    PubMed

    Keller, Lena Katharina; Grünewald, Barbara; Vetter, Céline; Roenneberg, Till; Schulte-Körne, Gerd

    2017-03-29

    The relationship between sleep and adolescent depression is much discussed, but still not fully understood. One important sleep variable is self-selected sleep timing, which is also referred to as chronotype. Chronotype is mostly regulated by the circadian clock that synchronises the internal time of the body with the external light dark cycle. A late chronotype as well as a misalignment between internal time and external time such as social jetlag has been shown to be associated with depressive symptoms in adults. In this study, we investigated whether adolescents with remitted depression differ from healthy controls in terms of chronotype, social jetlag and other sleep-related variables. For this purpose, we assessed chronotype and social jetlag with the Munich ChronoType Questionnaire (MCTQ), subjective sleep quality with the Pittsburgh Sleep Quality Index (PSQI) and used continuous wrist-actimetry over 31 consecutive days to determine objective sleep timing. Given the potentially mediating effect of light on chronotype and depressive symptoms, we measured light exposure with a light sensor on the actimeter. In our sample, adolescents with remitted depression showed similar chronotypes and similar amounts of social jetlag compared to controls. However, patients with remitted depression slept significantly longer on work-free days and reported a worse subjective sleep quality than controls. Additionally, light exposure in remitted patients was significantly higher, but this finding was mediated by living in a rural environment. These findings indicate that chronotype might be modified during remission, which should be further investigated in longitudinal studies.

  6. Comparative Evaluation of the Impact of Subacute Exposure of Smokeless Tobacco and Tobacco Smoke on Rat Testis

    PubMed Central

    Aprioku, Jonah Sydney; Ugwu, Theresa Chioma

    2015-01-01

    This study investigated the effects of 30-day exposure to tobacco smoke (TS), smokeless tobacco (ST), and nicotine on reproductive parameters and oxidative biomarkers in prepubertal and adult male rats. Sperm motility was reduced by 77.5 and 89.0% in TS and ST exposed prepubertal rats and 71.1 and 86.4% in adult rats, respectively. Sperm count was also reduced by 64.7 and 89.9% in prepubertal rats and 64.9 and 47.0% in adult rats, respectively. Nicotine decreased sperm motility (82.2%) and count (62.6%) in prepubertal rats but caused no effect in adult rats. There were no changes in sperm morphology; testosterone was decreased, while LH and FSH were increased in exposed rats, when compared with control. Malondialdehyde levels in testes of exposed rats were increased, and GSH, SOD, and catalase were altered. Results indicate that subacute exposure of tobacco products alters sperm characteristics in a rank order of ST > TS > nicotine, which may be linked to increase in oxidative stress in the testis. PMID:26634225

  7. Gamma-ray double-layered transmission exposure buildup factors of some engineering materials, a comparative study

    NASA Astrophysics Data System (ADS)

    Mann, Kulwinder Singh; Heer, Manmohan Singh; Rani, Asha

    2016-08-01

    Comparative study on various deterministic methods and formulae of double layered transmission exposure buildup factors (DLEBF) for point isotropic gamma-ray sources has been performed and the results are provided here. This investigation has been performed on some commonly available engineering materials for the purpose of gamma-ray shielding. In reality, the presence of air around the gamma-ray shield motivated to focus this study on exposure buildup factor (EBF). DLEBF have been computed at four energies viz. 0.5, 1.0, 2.0 and 3.0 MeV for various combinations of the chosen five samples taken two at a time with combined optical thickness up to 8 mean free path (mfp). For the necessary computations for DLEBF, a computer program (BUF-toolkit) has been designed. Comparison of Monte Carlo (EGS4-code) and Geometric Progression (G.P.) fitting point kernel methods were done for DLEBF computation. It is concluded that empirical formula given by Lin and Jiang using EBF computed by G.P. fitting formula is the most accurate and easiest method for DLEBF computations. It was observed that DLEBF values at selected energies for two layered slabs with an orientation (low-Z material followed by high-Z material) were lower than the opposite orientation. For optical thickness up to 8 mfp and chosen energy range (0.5-3.0 MeV), Aluminum-Lime Stone shield, appears to provide the best protection against the gamma-rays.

  8. Ultraviolet spectral distribution and erythema-weighted irradiance from indoor tanning devices compared with solar radiation exposures.

    PubMed

    Sola, Yolanda; Baeza, David; Gómez, Miguel; Lorente, Jerónimo

    2016-08-01

    Concern regarding the impact of indoor tanning devices on human health has led to different regulations and recommendations, which set limits on erythema-weighted irradiance. Here, we analyze spectral emissions from 52 tanning devices in Spanish facilities and compare them with surface solar irradiance for different solar zenith angles. Whereas most of the devices emitted less UV-B radiation than the midday summer sun, the unweighted UV-A irradiance was 2-6 times higher than solar radiation. Moreover, the spectral distributions of indoor devices were completely different from that of solar radiation, differing in one order of magnitude at some UV-A wavelengths, depending on the lamp characteristics. In 21% of the devices tested, the erythema-weighted irradiance exceeded 0.3Wm(-2): the limit fixed by the European standard and the Spanish regulation. Moreover, 29% of the devices fall within the UV type 4 classification, for which medical advice is required. The high variability in erythema-weighted irradiance results in a wide range of exposure times to reach 1 standard erythemal dose (SED: 100Jm(-2)), with 62% of devices requiring exposures of <10min to reach 1 SED. Nevertheless, the unweighted UV-A dose during this time period would be from 1.4 to 10.3 times more than the solar UV-A dose.

  9. Biological monitoring of smoke exposure among wildland firefighters: Apilot study comparing urinary methoxyphenols with personal exposures to carbon monoxide, particulate matter, and levoglucosan.

    SciTech Connect

    Neitzel, R.; Naeher, L., P.; Paulsen, M.; Dunn, R.; Stock, A.; Simpson, C., D.

    2008-04-01

    Urinary methoxyphenols (MPs) have been proposed as biomarkers of woodsmoke exposure. However, few field studies have been undertaken to evaluate the relationship between woodsmoke exposure and urinary MP concentrations. We conducted a pilot study at the US Forest Service Savannah River Site, in which carbon monoxide (CO), levoglucosan (LG), and particulate matter (PM2.5) exposures were measured in wildland firefighters on prescribed burn days. Pre- and post-shift urine samples were collected from each subject, and cross-shift changes in creatinine-corrected urinary MP concentrations were calculated. Correlations between exposure measures and creatine-adjusted urinary MP concentrations were explored, and regression models were developed relating changes in urinary MP concentrations to measured exposure levels. Full-shift measurements were made on 13 firefighters over 20 work shifts in winter 2004 at the US Forest Service Savannah River site, a National Environmental Research Park. The average workshift length across the 20 measured shifts was 701±95 min. LG and CO exposures were significantly correlated for samples where the filter measurement captured at least 60% of the work shift (16 samples), as well as for the smaller set of full-shift exposure samples (n¼9). PM2.5 and CO exposures were not significantly correlated, and LG and PM2.5 exposures were only significantly correlated for samples representing at least 60% of the work shift. Creatinine-corrected urinary concentrations for 20 of the 22 MPs showed cross-shift increases, with 14 of these changes showing statistical significance. Individual and summed creatinine-adjusted guaiacol urinary MPs were highly associated with CO (and, to a lesser degree, LG) exposure levels, and random-effects regression models including CO and LG exposure levels explained up to 80% of the variance in cross-shift changes in summed creatinine-adjusted guaiacol urinary MP concentrations. Although limited by the small sample size

  10. Biological monitoring of smoke exposure among wildland firefighters: A pilot study comparing urinary methoxyphenols with personal exposures to carbon monoxide, particulate matter, and levoglucosan.

    SciTech Connect

    Neitzel, R.; Naeher, L., P.; Paulsen, M.; Dunn, R.; Stock, A.; Simpson, C., D.

    2009-04-01

    Urinary methoxyphenols (MPs) have been proposed as biomarkers of woodsmoke exposure. However, few field studies have been undertaken to evaluate the relationship between woodsmoke exposure and urinary MP concentrations. We conducted a pilot study at the US Forest ServiceFSavannah River Site, in which carbon monoxide (CO), levoglucosan (LG), and particulate matter (PM2.5) exposures were measured in wildland firefighters on prescribedburn days. Pre- and post-shift urine samples were collected from each subject, and cross-shift changes in creatinine-corrected urinary MP concentrations were calculated. Correlations between exposure measures and creatine-adjusted urinary MP concentrations were explored, and regression models were developed relating changes in urinary MP concentrations to measured exposure levels. Full-shift measurements were made on 13 firefighters over 20 work shifts in winter 2004 at the US Forest Service Savannah River site, a National Environmental Research Park. The average workshift length across the 20 measured shifts was 701±95 min. LG and CO exposures were significantly correlated for samples where the filter measurement captured at least 60% of the work shift (16 samples), as well as for the smaller set of full-shift exposure samples (n¼9). PM2.5 and CO exposures were not significantly correlated, and LG and PM2.5 exposures were only significantly correlated for samples representing at least 60% of the work shift. Creatinine-corrected urinary concentrations for 20 of the 22 MPs showed cross-shift increases, with 14 of these changes showing statistical significance. Individual and summed creatinine-adjusted guaiacol urinary MPs were highly associated with CO (and, to a lesser degree, LG) exposure levels, and random-effects regression models including CO and LG exposure levels explained up to 80% of the variance in cross-shift changes in summed creatinine-adjusted guaiacol urinary MP concentrations. Although limited by the small sample size

  11. Biological monitoring of smoke exposure among wildland firefighters: Apilot study comparing urinary methoxyphenols with personal exposures to carbon monoxide, particulate matter, and levoglucosan.

    SciTech Connect

    Neitzel, R.; Naeher, L., P.; Paulsen, M.; Dunn, R.; Stock, A.; Simpson, C., D.

    2009-04-01

    Urinary methoxyphenols (MPs) have been proposed as biomarkers of woodsmoke exposure. However, few field studies have been undertaken to evaluate the relationship between woodsmoke exposure and urinary MP concentrations. We conducted a pilot study at the US Forest Service Savannah River Site, in which carbon monoxide (CO), levoglucosan (LG), and particulate matter (PM2.5) exposures were measured in wildland firefighters on prescribed burn days. Pre- and post-shift urine samples were collected from each subject, and cross-shift changes in creatinine-corrected urinary MP concentrations were calculated. Correlations between exposure measures and creatine-adjusted urinary MP concentrations were explored, and regression models were developed relating changes in urinary MP concentrations to measured exposure levels. Full-shift measurements were made on 13 firefighters over 20 work shifts in winter 2004 at the US Forest Service Savannah River site, a National Environmental Research Park. The average workshift length across the 20 measured shifts was 701±95 min. LG and CO exposures were significantly correlated for samples where the filter measurement captured at least 60% of the work shift (16 samples), as well as for the smaller set of full-shift exposure samples (n¼9). PM2.5 and CO exposures were not significantly correlated, and LG and PM2.5 exposures were only significantly correlated for samples representing at least 60% of the work shift. Creatinine-corrected urinary concentrations for 20 of the 22 MPs showed cross-shift increases, with 14 of these changes showing statistical significance. Individual and summed creatinine-adjusted guaiacol urinary MPs were highly associated with CO (and, to a lesser degree, LG) exposure levels, and random-effects regression models including CO and LG exposure levels explained up to 80% of the variance in cross-shift changes in summed creatinine-adjusted guaiacol urinary MP concentrations. Although limited by the small sample size

  12. Biological monitoring of smoke exposure among wildland firefighters: A pilot study comparing urinary methoxyphenols with personal exposures to carbon monoxide, particulate matter, and levoglucosan.

    SciTech Connect

    Neitzel, R.; Naeher, L., P.; Paulsen, M.; Dunn, R.; Stock, A.; Simpson, C., D.

    2009-04-01

    Urinary methoxyphenols (MPs) have been proposed as biomarkers of woodsmoke exposure. However, few field studies have been undertaken to evaluate the relationship between woodsmoke exposure and urinary MP concentrations. We conducted a pilot study at the US Forest Service Savannah River Site, in which carbon monoxide (CO), levoglucosan (LG), and particulate matter (PM2.5) exposures were measured in wildland firefighters on prescribed burn days. Pre- and post-shift urine samples were collected from each subject, and cross-shift changes in creatinine-corrected urinary MP concentrations were calculated. Correlations between exposure measures and creatine-adjusted urinary MP concentrations were explored, and regression models were developed relating changes in urinary MP concentrations to measured exposure levels. Full-shift measurements were made on 13 firefighters over 20 work shifts in winter 2004 at the US Forest Service Savannah River site, a National Environmental Research Park. The average workshift length across the 20 measured shifts was 701±95 min. LG and CO exposures were significantly correlated for samples where the filter measurement captured at least 60% of the work shift (16 samples), as well as for the smaller set of full-shift exposure samples (n¼9). PM2.5 and CO exposures were not significantly correlated, and LG and PM2.5 exposures were only significantly correlated for samples representing at least 60% of the work shift. Creatinine-corrected urinary concentrations for 20 of the 22 MPs showed cross-shift increases, with 14 of these changes showing statistical significance. Individual and summed creatinine-adjusted guaiacol urinary MPs were highly associated with CO (and, to a lesser degree, LG) exposure levels, and random-effects regression models including CO and LG exposure levels explained up to 80% of the variance in cross-shift changes in summed creatinine-adjusted guaiacol urinary MP concentrations. Although limited by the small sample size

  13. Biological monitoring of smoke exposure among wildland firefighters: Apilot study comparing urinary methoxyphenols with personal exposures to carbon monoxide, particulate matter, and levoglucosan.

    SciTech Connect

    Neitzel, R.; Naeher, L., P.; Paulsen, M.; Dunn, R.; Stock, A.; Simpson, C., D.

    2009-04-01

    Urinary methoxyphenols (MPs) have been proposed as biomarkers of woodsmoke exposure. However, few field studies have been undertaken to evaluate the relationship between woodsmoke exposure and urinary MP concentrations. We conducted a pilot study at the US Forest ServiceFSavannah River Site, in which carbon monoxide (CO), levoglucosan (LG), and particulate matter (PM2.5) exposures were measured in wildland firefighters on prescribed burn days. Pre- and post-shift urine samples were collected from each subject, and cross-shift changes in creatinine-corrected urinary MP concentrations were calculated. Correlations between exposure measures and creatine-adjusted urinary MP concentrations were explored, and regression models were developed relating changes in urinary MP concentrations to measured exposure levels. Full-shift measurements were made on 13 firefighters over 20 work shifts in winter 2004 at the US Forest Service Savannah River site, a National Environmental Research Park. The average workshift length across the 20 measured shifts was 701±95 min. LG and CO exposures were significantly correlated for samples where the filter measurement captured at least 60% of the work shift (16 samples), as well as for the smaller set of full-shift exposure samples (n¼9). PM2.5 and CO exposures were not significantly correlated, and LG and PM2.5 exposures were only significantly correlated for samples representing at least 60% of the work shift. Creatinine-corrected urinary concentrations for 20 of the 22 MPs showed cross-shift increases, with 14 of these changes showing statistical significance. Individual and summed creatinine-adjusted guaiacol urinary MPs were highly associated with CO (and, to a lesser degree, LG) exposure levels, and random-effects regression models including CO and LG exposure levels explained up to 80% of the variance in cross-shift changes in summed creatinine-adjusted guaiacol urinary MP concentrations. Although limited by the small sample size

  14. Comparative Analysis of Cryptography Library in IoT

    NASA Astrophysics Data System (ADS)

    Kumar, Uday; Borgohain, Tuhin; Sanyal, Sugata

    2015-05-01

    The paper aims to do a survey along with a comparative analysis of the various cryptography libraries that are applicable in the field of Internet of Things (IoT). The first half of the paper briefly introduces the various cryptography libraries available in the field of cryptography along with a list of all the algorithms contained within the libraries. The second half of the paper deals with cryptography libraries specifically aimed for application in the field of Internet of Things. The various libraries and their performance analysis listed down in this paper are consolidated from various sources with the aim of providing a single comprehensive repository for reference to the various cryptography libraries and the comparative analysis of their features in IoT.

  15. Analysis of School Commuting Data for Exposure Modeling Purposes

    SciTech Connect

    Xue, Jianping; McCurdy, Thomas; Burke, Janet; Bhaduri, Budhendra L; Liu, Cheng; Nutaro, James J; Patterson, Lauren A

    2010-01-01

    Human exposure models often make the simplifying assumption that school children attend school in the same census tract where they live. This paper analyzes that assumption and provides information on the temporal and spatial distributions associated with school commuting. The data were obtained using Oak Ridge National Laboratory s LandScan USA population distribution model (Bhaduri et al., 2007) applied to Philadelphia PA. It is a high-resolution model used to allocate individual school-aged children to both a home and school location, and to devise a minimum-time home-to school commuting path (called a trace) between the two locations. LandScan relies heavily on Geographic Information System (GIS) data. Our GIS analyses found that in Philadelphia: (1) about 32% of the students walk across 2 or more census tracts and 40% of them walk across 4 or more census blocks; (2) 60% drive across 4 or more census tracts going to school and 50% drive across 10 or more census blocks; (3) five-minute commuting time intervals result in misclassification as high as 90% for census blocks, 70% for block groups, and 50% for census tracts; (4) a one-minute time interval is needed to reasonably resolve time spent in the various census unit designations; (5) approximately 50% of both schoolchildren s homes and schools are located within 160 m of highly-traveled roads, and 64% of the schools are located within 200 m. These findings are very important when modeling school children s exposures, especially when ascertaining the impacts of near-roadway concentrations on their total daily body burden. Since many school children also travel along these streets and roadways to get to school, a majority of children in Philadelphia are in mobile-source dominated locations most of the day. We hypothesize that exposures of school children in Philadelphia to benzene and particulate matter will be much higher than if home and school locations and commuting paths at a 1-minute time resolution are

  16. A principal factor analysis to characterize agricultural exposures among Nebraska veterans

    PubMed Central

    Weissenburger-Moser, Lisa; Meza, Jane; Yu, Fang; Shiyanbola, Oyewale; Romberger, Debra J; LeVan, Tricia D

    2017-01-01

    Agricultural workers are at an increased risk of developing chronic respiratory disorders. Accurate estimation of long-term agricultural exposures based on questionnaires has been used to improve the validity of epidemiologic investigations and subsequent evaluation of the association between agricultural exposures and chronic diseases. Our aim was to use principal factor analysis (PFA) to distill exposure data into essential variables characterizing long-term agricultural exposures. This is a cross-sectional study of veterans between the ages of 40 and 80 years and who worked on a farm for ≥2 years. Participant characteristics were: 98.1% were white males with a mean age 65±8 (SD) years and 39.8% had chronic obstructive pulmonary disease. The final model included four factors and explained 16.6% of the variance in the exposure data. Factor 1 was a heterogeneous factor; however, Factor 2 was exclusively composed of exposure to livestock such as hogs, dairy and poultry. Factor 3 included exposures from jobs on or off the farm such as wood dust, mineral dust, asbestos and spray paint. Crop exposure loaded exclusively in Factor 4 and included lifetime hours of exposure and maximum number of acres farmed in the participants' lifetime. The factors in the final model were interpretable and consistent with farming practices. PMID:27049536

  17. Hepatic Proteome Analysis of Atlantic Salmon (Salmo salar) After Exposure to Environmental Concentrations of Human Pharmaceuticals*

    PubMed Central

    Hampel, Miriam; Alonso, Esteban; Aparicio, Irene; Santos, Juan Luis; Leaver, Michael

    2015-01-01

    Pharmaceuticals are pseudopersistent aquatic pollutants with unknown effects at environmentally relevant concentrations. Atlantic salmon (Salmo salar) were exposed to Acetaminophen: 54.77 ± 34.67; Atenolol: 11.08 ± 7.98, and Carbamazepine: 7.85 ± 0.13 μg·L−1 for 5 days. After Acetaminophen treatment, 19 proteins were differently expressed, of which 11 were significant with respect to the control group (eight up-regulated and three down-regulated). After Atenolol treatment, seven differently expressed proteins were obtained in comparison with the control, of which six could be identified (four up-regulated and two down-regulated). Carbamazepine exposure resulted in 15 differently expressed proteins compared with the control, with 10 of them identified (seven up-regulated and three down-regulated). Out of these, three features were common between Acetaminophen and Carbamazepine and one between Carbamazepine and Atenolol. One feature was common across all treatments. Principal component analysis and heat map clustering showed a clear grouping of the variability caused by the applied treatments. The obtained data suggest (1) that exposure to environmentally relevant concentrations of the pharmaceuticals alters the hepatic protein expression profile of the Atlantic salmon; and (2) the existence of treatment specific processes that may be useful for biomarker development. PMID:25394398

  18. Do self-statements enhance the effectiveness of virtual reality exposure therapy? A comparative evaluation in acrophobia.

    PubMed

    Krijn, M; Emmelkamp, P M G; Olafsson, R P; Schuemie, Martijn J; van der Mast, Charles A P G

    2007-06-01

    There is a clear need for more detailed analysis of the role of cognitive self-statements in virtual reality exposure therapy (VRET). To date, no research on this topic has been done. The primary aim of this study was to investigate whether coping self-statements would enhance the effectiveness of VRET. In a randomized crossover design, 26 patients with acrophobia (DSM-IV diagnosis of specific phobia) were randomly assigned to two sessions of VRET followed by two sessions of VRET plus coping self-statements, or the other way around: first two sessions of VRET plus coping self-statements followed by two sessions of VRET. Results showed that VRET, regardless of addition of coping self-statements, decreased anxiety of heights, decreased avoidance of height situations, and improved attitudes towards heights. However, at 6-month follow-up, most gains during treatment were not fully retained.

  19. Comparing non-occupational post-exposure prophylaxis drug regimens for HIV: insights from a linked HIV surveillance system.

    PubMed

    Pierce, Anna B; El-Hayek, Carol; McCarthy, Damien; Armishaw, Jude; Watson, Kerrie; Wilkinson, Anna; Price, Brian; Wright, Edwina J; Hoy, Jennifer F; Stoové, Mark A

    2016-12-05

    Background: International non-occupational post-exposure prophylaxis (NPEP) guidelines recommend routine use of three drug NPEP regimens, despite absence of evidence for greater prevention efficacy compared with two drug regimens. This study examines the potential for excess HIV seroconversions among high-risk men who have sex with men (MSM) reporting receptive anal intercourse with a source of unknown HIV serostatus (RAIU) following a two-drug versus a three-drug NPEP regimen. Methods: Data for MSM in the Victorian NPEP service database between 10 August 2005 and 31 December 2012 were linked with all Victorian HIV notifications up to 31 December 2013. The primary outcome was NPEP failure following NPEP presentation among MSM reporting RAIU, stratified by the number of drugs prescribed. Results: Among 1482 MSM reporting 2002 episodes of RAIU and prescribed two- or three-drug NPEP, 70 seroconverted to HIV, but only 19 were considered possible NPEP failures. HIV diagnosis incidence among men reporting RAIU was 1.2/100 person years (PY) (95%CI=1.0-1.6); 1.1/100 PY (95%CI=0.8-1.4) among MSM prescribed two drugs and 2.2/100 PY (95%CI=1.4-3.7) among MSM prescribed three drugs (P<0.01). Of the 19 possible NPEP failures, 13 (0.7%) were prescribed two drugs and six (2.7%) three drugs (P<0.001). Conclusions: This study suggests that two-drug NPEP regimens do not result in excess seroconversions compared with three-drug regimens when used following RAIU. Clinical services should carefully consider their use of three drug NPEP and whether resources might be better invested in other prevention strategies, particularly pre-exposure prophylaxis (PrEP).

  20. Effects of lactational exposure of olanzapine and risperidone on hematology and lymphoid organs histopathology: a comparative study in mice neonates.

    PubMed

    Mishra, Akash C; Mohanty, Banalata

    2010-05-25

    Body weight gain, sexual/reproductive dysfunction and hematological abnormalities are serious consequences of atypical antipsychotics treatment. No attempts however have been made preclinically to elucidate the adverse hematological impacts. Presently, effects of lactational exposure of olanzapine (4, 8 and 10 mg/kg) and risperidone (1 and 2 mg/kg) on hematology as well as lymphoid organ histopathology of mice neonates were investigated. Both olanzapine and risperidone transfers through milk and make the neonates susceptible to their adverse side effects. Corticosterone elevation tendency of both the drugs further enhance the susceptibility for immune dysfunction. Analysis of total and differential leukocytes counts revealed neutropenia with all the doses of olanzapine but only with risperidone 2mg/kg. Weight analysis and histopathology of thymus and spleen indicated a state of suppression; less in the risperidone-exposed groups. Significant plasma corticosterone elevation occurred on 4 and 8 mg/kg olanzapine exposures but not with 10 mg/kg as well as with both the risperidone doses. Elevation of plasma prolactin levels occurred dose-dependently for both the drugs. Hematological toxicity (neutropenia) might be the direct toxic effects of the drugs/unstable metabolites on circulating neutrophils and/or on the bone marrow hemopoietic cells. Direct toxicity of the drugs might also have suppressed the lymphoid organs thymus and spleen. Further, it could be associated to hormonal imbalance induced by adverse pharmacological effects of the drugs on the endocrine system. Suppression of lymphoid organs in olanzapine groups might have resulted because of corticosteronemia and hyperprolactinemia, while in risperidone it could be mediated by pronounced hyperprolactinemic effect alone.

  1. Dermoscopy analysis of RGB-images based on comparative features

    NASA Astrophysics Data System (ADS)

    Myakinin, Oleg O.; Zakharov, Valery P.; Bratchenko, Ivan A.; Artemyev, Dmitry N.; Neretin, Evgeny Y.; Kozlov, Sergey V.

    2015-09-01

    In this paper, we propose an algorithm for color and texture analysis for dermoscopic images of human skin based on Haar wavelets, Local Binary Patterns (LBP) and Histogram Analysis. This approach is a modification of «7-point checklist» clinical method. Thus, that is an "absolute" diagnostic method because one is using only features extracted from tumor's ROI (Region of Interest), which can be selected manually and/or using a special algorithm. We propose additional features extracted from the same image for comparative analysis of tumor and healthy skin. We used Euclidean distance, Cosine similarity, and Tanimoto coefficient as comparison metrics between color and texture features extracted from tumor's and healthy skin's ROI separately. A classifier for separating melanoma images from other tumors has been built by SVM (Support Vector Machine) algorithm. Classification's errors with and without comparative features between skin and tumor have been analyzed. Significant increase of recognition quality with comparative features has been demonstrated. Moreover, we analyzed two modes (manual and automatic) for ROI selecting on tumor and healthy skin areas. We have reached 91% of sensitivity using comparative features in contrast with 77% of sensitivity using the only "absolute" method. The specificity was the invariable (94%) in both cases.

  2. Evaluating the Risks of Clinical Research: Direct Comparative Analysis

    PubMed Central

    Abdoler, Emily; Roberson-Nay, Roxann; Pine, Daniel S.; Wendler, David

    2014-01-01

    Abstract Objectives: Many guidelines and regulations allow children and adolescents to be enrolled in research without the prospect of clinical benefit when it poses minimal risk. However, few systematic methods exist to determine when research risks are minimal. This situation has led to significant variation in minimal risk judgments, raising concern that some children are not being adequately protected. To address this concern, we describe a new method for implementing the widely endorsed “risks of daily life” standard for minimal risk. This standard defines research risks as minimal when they do not exceed the risks posed by daily life activities or routine examinations. Methods: This study employed a conceptual and normative analysis, and use of an illustrative example. Results: Different risks are composed of the same basic elements: Type, likelihood, and magnitude of harm. Hence, one can compare the risks of research and the risks of daily life by comparing the respective basic elements with each other. We use this insight to develop a systematic method, direct comparative analysis, for implementing the “risks of daily life” standard for minimal risk. The method offers a way of evaluating research procedures that pose the same types of risk as daily life activities, such as the risk of experiencing anxiety, stress, or other psychological harm. We thus illustrate how direct comparative analysis can be applied in practice by using it to evaluate whether the anxiety induced by a respiratory CO2 challenge poses minimal or greater than minimal risks in children and adolescents. Conclusions: Direct comparative analysis is a systematic method for applying the “risks of daily life” standard for minimal risk to research procedures that pose the same types of risk as daily life activities. It thereby offers a method to protect children and adolescents in research, while ensuring that important studies are not blocked because of unwarranted concerns about

  3. Comparing efficiency of micro-RNA and mRNA biomarker liberation with microbubble-enhanced ultrasound exposure.

    PubMed

    Forbrich, Alex; Paproski, Robert; Hitt, Mary; Zemp, Roger

    2014-09-01

    Blood biomarkers are potentially powerful diagnostic tools that are limited clinically by low concentrations, the inability to determine biomarker origin and unknown patient baseline. Recently, ultrasound has been shown to liberate proteins and large mRNA biomarkers, overcoming many of these limitations. We have since demonstrated that adding lipid-stabilized microbubbles elevates mRNA concentration an order of magnitude compared with ultrasound without microbubbles, in vitro. Unfortunately the large size of some mRNA molecules may limit efficiency of release and hinder efficacy as an ultrasound-liberated biomarker. We hypothesize that smaller molecules will be released more efficiently with ultrasound than larger molecules. Although investigation of large libraries of biomarkers should be performed to fully validate this hypothesis, we focus on a small subset of mRNA and micro-RNAs. Specifically, we focus on miR-21 (22 base pairs [bp]), which is upregulated in certain forms of cancer, compared with previously investigated mammaglobin mRNA (502 bp). We also report release of micro-RNA miR-155 (22 bp) and housekeeping rRNA S18 (1869 bp). More than 10 million additional miR-21 copies per 100,000 cells are released with ultrasound-microbubble exposure. The low- molecular-weight miR-21 proved to be liberated 50 times more efficiently than high-molecular-weight mammaglobin mRNA, releasing orders of magnitude more miR-21 than mammaglobin mRNA under comparable conditions.

  4. European sea bass gill pathology after exposure to cadmium and terbuthylazine: expert versus fractal analysis.

    PubMed

    Manera, M; Giari, L; Depasquale, J A; Dezfuli, B S

    2016-03-01

    The objective of this study was to compare expert versus fractal analysis as new methods to evaluate branchial lamellar pathology in European sea bass Dicentrarchus labrax (Linnaeus, 1758) experimentally exposed to cadmium and to terbuthylazine. In particular, guided expert quantitative and fractal analysis were performed on selected images from semithin sections to test possible differences according to exposure class (unexposed, cadmium exposed, or terbuthylazine exposed) and the discrimination power of the two methods. With respect to guided expert quantitative analysis, the following elementary pathological features were assessed according to pre-determined cover classes: 'epithelial lifting', 'epithelial shrinkage', 'epithelial swelling', 'pillar cells coarctation', 'pillar cells detachment', 'channels fusion', 'chloride cells swelling' and 'chloride cells invasion'. Considering fractal analysis, DB (box dimension), DM (mass dimension), Dx (mean fractal dimension) as fractal dimensions and lacunarity from DM and Dx scan types were calculated both from the outlined and skeletonized (one pixel wide lines) images. Despite significant differences among experimental classes, only expert analysis provided good discrimination with correct classification of 91.7 % of the original cases, and of 87.5 % of the cross-validated cases, with a sensitivity of 95.45 % and 91.3 %, respectively, and a specificity of 75 % in both cases. Guided expert quantitative analysis appears to be a reliable method to objectively characterize fish gill pathology and may represent a powerful tool in environmental biomonitoring to ensure proper standardization and reproducibility. Though fractal analysis did not equal the discrimination power of the expert method, it certainly warrants further study to evaluate local variations in complexity or possible multiple scaling rules.

  5. Comparative genomic analysis of eutherian interferon-γ-inducible GTPases.

    PubMed

    Premzl, Marko

    2012-11-01

    The interferon-γ-inducible GTPases, IFGGs, are intracellular proteins involved in immune response against pathogens. A comprehensive comparative genomic review and analysis of eutherian IFGGs was carried out using public genomic sequences. The 64 eutherian IFGG genes were examined in detail and annotated. The eutherian IFGG promoter types were first catalogued followed by a phylogenetic analysis of eutherian IFGGs, which described five major IFGG clusters. The patterns of differential gene expansions and protein regions that may regulate IFGG catalytic features suggested a new classification of eutherian IFGGs. This mini-review has also provided new tests of reliability of public genomic sequences as well as tests of protein molecular evolution.

  6. Comparative analysis of two DOPA dioxygenases from Phytolacca Americana.

    PubMed

    Takahashi, Kana; Yoshida, Kazuko; Sakuta, Masaaki

    2015-05-01

    The comparative analysis of two Phytolacca americana DOPA dioxygenases (PaDOD1 and PaDOD2) that may be involved in betalain biosynthesis was carried out. The recombinant protein of PaDOD catalyzed the conversion of DOPA to betalamic acid, whereas DOD activity was not detected in PaDOD2 in vitro. The role of DOD genes is discussed in the evolutionary context using phylogenetic analysis, suggesting that DOD might have been duplicated early in evolution and that accumulation of base substitutions could have led to the different characteristics of DODs within the betalain-producing Caryophyllales.

  7. The association between noise exposure and blood pressure and ischemic heart disease: a meta-analysis.

    PubMed Central

    van Kempen, Elise E M M; Kruize, Hanneke; Boshuizen, Hendriek C; Ameling, Caroline B; Staatsen, Brigit A M; de Hollander, Augustinus E M

    2002-01-01

    It has been suggested that noise exposure is associated with blood pressure changes and ischemic heart disease risk, but epidemiologic evidence is still limited. Furthermore, most reviews investigating these relations were not carried out in a systematic way, which makes them more prone to bias. We conducted a meta-analysis of 43 epidemiologic studies published between 1970 and 1999 that investigate the relation between noise exposure (both occupational and community) and blood pressure and/or ischemic heart disease (International Classification of Diseases, Ninth Revision, codes 410-414). We studied a wide range of effects, from blood pressure changes to a myocardial infarction. With respect to the association between noise exposure and blood pressure, small blood pressure differences were evident. Our meta-analysis showed a significant association for both occupational noise exposure and air traffic noise exposure and hypertension: We estimated relative risks per 5 dB(A) noise increase of 1.14 (1.01-1.29) and 1.26 (1.14-1.39), respectively. Air traffic noise exposure was positively associated with the consultation of a general practitioner or specialist, the use of cardiovascular medicines, and angina pectoris. In cross-sectional studies, road traffic noise exposure increases the risk of myocardial infarction and total ischemic heart disease. Although we can conclude that noise exposure can contribute to the prevalence of cardiovascular disease, the evidence for a relation between noise exposure and ischemic heart disease is still inconclusive because of the limitations in exposure characterization, adjustment for important confounders, and the occurrence of publication bias. PMID:11882483

  8. Pesticide exposure and risk of Alzheimer’s disease: a systematic review and meta-analysis

    NASA Astrophysics Data System (ADS)

    Yan, Dandan; Zhang, Yunjian; Liu, Liegang; Yan, Hong

    2016-09-01

    Evidence suggests that lifelong cumulative exposure to pesticides may generate lasting toxic effects on the central nervous system and contribute to the development of Alzheimer’s disease (AD). A number of reports indicate a potential association between long-term/low-dose pesticide exposure and AD, but the results are inconsistent. Therefore, we conducted a meta-analysis to clarify this association. Relevant studies were identified according to inclusion criteria. Summary odds ratios (ORs) were calculated using fixed-effects models. A total of seven studies were included in our meta-analysis. A positive association was observed between pesticide exposure and AD (OR = 1.34 95% confidence interval [CI] = 1.08, 1.67; n = 7). The summary ORs with 95% CIs from the crude and adjusted effect size studies were 1.14 (95% CI = 0.94, 1.38; n = 7) and 1.37 (95% CI = 1.09, 1.71; n = 5), respectively. The sensitivity analyses of the present meta-analysis did not substantially modify the association between pesticide exposure and AD. Subgroup analyses revealed that high-quality studies tended to show significant relationships. The present meta-analysis suggested a positive association between pesticide exposure and AD, confirming the hypothesis that pesticide exposure is a risk factor for AD. Further high-quality cohort and case-control studies are required to validate a causal relationship.

  9. Pesticide exposure and risk of Alzheimer’s disease: a systematic review and meta-analysis

    PubMed Central

    Yan, Dandan; Zhang, Yunjian; Liu, Liegang; Yan, Hong

    2016-01-01

    Evidence suggests that lifelong cumulative exposure to pesticides may generate lasting toxic effects on the central nervous system and contribute to the development of Alzheimer’s disease (AD). A number of reports indicate a potential association between long-term/low-dose pesticide exposure and AD, but the results are inconsistent. Therefore, we conducted a meta-analysis to clarify this association. Relevant studies were identified according to inclusion criteria. Summary odds ratios (ORs) were calculated using fixed-effects models. A total of seven studies were included in our meta-analysis. A positive association was observed between pesticide exposure and AD (OR = 1.34; 95% confidence interval [CI] = 1.08, 1.67; n = 7). The summary ORs with 95% CIs from the crude and adjusted effect size studies were 1.14 (95% CI = 0.94, 1.38; n = 7) and 1.37 (95% CI = 1.09, 1.71; n = 5), respectively. The sensitivity analyses of the present meta-analysis did not substantially modify the association between pesticide exposure and AD. Subgroup analyses revealed that high-quality studies tended to show significant relationships. The present meta-analysis suggested a positive association between pesticide exposure and AD, confirming the hypothesis that pesticide exposure is a risk factor for AD. Further high-quality cohort and case-control studies are required to validate a causal relationship. PMID:27581992

  10. Virtual reality compared with in vivo exposure in the treatment of social anxiety disorder: a three-arm randomised controlled trial.

    PubMed

    Bouchard, Stéphane; Dumoulin, Stéphanie; Robillard, Geneviève; Guitard, Tanya; Klinger, Évelyne; Forget, Hélène; Loranger, Claudie; Roucaut, François Xavier

    2017-04-01

    BackgroundPeople with social anxiety disorder (SAD) fear social interactions and may be reluctant to seek treatments involving exposure to social situations. Social exposure conducted in virtual reality (VR), embedded in individual cognitive-behavioural therapy (CBT), could be an answer.AimsTo show that conducting VR exposure in CBT for SAD is effective and is more practical for therapists than conducting exposure in vivoMethodParticipants were randomly assigned to either VR exposure (n = 17), in vivo exposure (n = 22) or waiting list (n = 20). Participants in the active arms received individual CBT for 14 weekly sessions and outcome was assessed with questionnaires and a behaviour avoidance test. (Trial registration number ISRCTN99747069)ResultsImprovements were found on the primary (Liebowitz Social Anxiety Scale) and all five secondary outcome measures in both CBT groups compared with the waiting list. Conducting exposure in VR was more effective at post-treatment than in vivo on the primary outcome measure and on one secondary measure. Improvements were maintained at the 6-month follow-up. VR was significantly more practical for therapists than in vivo exposure.ConclusionsUsing VR can be advantageous over standard CBT as a potential solution for treatment avoidance and as an efficient, cost-effective and practical medium of exposure.

  11. Comparative Genomics via Wavelet Analysis for Closely Related Bacteria

    NASA Astrophysics Data System (ADS)

    Song, Jiuzhou; Ware, Tony; Liu, Shu-Lin; Surette, M.

    2004-12-01

    Comparative genomics has been a valuable method for extracting and extrapolating genome information among closely related bacteria. The efficiency of the traditional methods is extremely influenced by the software method used. To overcome the problem here, we propose using wavelet analysis to perform comparative genomics. First, global comparison using wavelet analysis gives the difference at a quantitative level. Then local comparison using keto-excess or purine-excess plots shows precise positions of inversions, translocations, and horizontally transferred DNA fragments. We firstly found that the level of energy spectra difference is related to the similarity of bacteria strains; it could be a quantitative index to describe the similarities of genomes. The strategy is described in detail by comparisons of closely related strains: S.typhi CT18, S.typhi Ty2, S.typhimurium LT2, H.pylori 26695, and H.pylori J99.

  12. Developmental and reproductive outcomes in humans and animals after glyphosate exposure: a critical analysis.

    PubMed

    Williams, Amy Lavin; Watson, Rebecca E; DeSesso, John M

    2012-01-01

    Glyphosate is the active ingredient of several widely used herbicide formulations. Glyphosate targets the shikimate metabolic pathway, which is found in plants but not in animals. Despite the relative safety of glyphosate, various adverse developmental and reproductive problems have been alleged as a result of exposure in humans and animals. To assess the developmental and reproductive safety of glyphosate, an analysis of the available literature was conducted. Epidemiological and animal reports, as well as studies on mechanisms of action related to possible developmental and reproductive effects of glyphosate, were reviewed. An evaluation of this database found no consistent effects of glyphosate exposure on reproductive health or the developing offspring. Furthermore, no plausible mechanisms of action for such effects were elucidated. Although toxicity was observed in studies that used glyphosate-based formulations, the data strongly suggest that such effects were due to surfactants present in the formulations and not the direct result of glyphosate exposure. To estimate potential human exposure concentrations to glyphosate as a result of working directly with the herbicide, available biomonitoring data were examined. These data demonstrated extremely low human exposures as a result of normal application practices. Furthermore, the estimated exposure concentrations in humans are >500-fold less than the oral reference dose for glyphosate of 2 mg/kg/d set by the U.S. Environmental Protection Agency (U.S. EPA 1993). In conclusion, the available literature shows no solid evidence linking glyphosate exposure to adverse developmental or reproductive effects at environmentally realistic exposure concentrations.

  13. Comparative visual analysis of 3D urban wind simulations

    NASA Astrophysics Data System (ADS)

    Röber, Niklas; Salim, Mohamed; Grawe, David; Leitl, Bernd; Böttinger, Michael; Schlünzen, Heinke

    2016-04-01

    Climate simulations are conducted in large quantity for a variety of different applications. Many of these simulations focus on global developments and study the Earth's climate system using a coupled atmosphere ocean model. Other simulations are performed on much smaller regional scales, to study very small fine grained climatic effects. These microscale climate simulations pose similar, yet also different, challenges for the visualization and the analysis of the simulation data. Modern interactive visualization and data analysis techniques are very powerful tools to assist the researcher in answering and communicating complex research questions. This presentation discusses comparative visualization for several different wind simulations, which were created using the microscale climate model MITRAS. The simulations differ in wind direction and speed, but are all centered on the same simulation domain: An area of Hamburg-Wilhelmsburg that hosted the IGA/IBA exhibition in 2013. The experiments contain a scenario case to analyze the effects of single buildings, as well as examine the impact of the Coriolis force within the simulation. The scenario case is additionally compared with real measurements from a wind tunnel experiment to ascertain the accuracy of the simulation and the model itself. We also compare different approaches for tree modeling and evaluate the stability of the model. In this presentation, we describe not only our workflow to efficiently and effectively visualize microscale climate simulation data using common 3D visualization and data analysis techniques, but also discuss how to compare variations of a simulation and how to highlight the subtle differences in between them. For the visualizations we use a range of different 3D tools that feature techniques for statistical data analysis, data selection, as well as linking and brushing.

  14. Systems analysis of the mechanisms of cardiac diastolic function changes after microgravity exposure

    NASA Astrophysics Data System (ADS)

    Summers, Richard; Coleman, Thomas; Steven, Platts; Martin, David

    Detailed information concerning cardiac function was collected by two-dimensional and M-mode echocardiography at 10 days before flight and 3h after landing in astronauts returning from shuttle missions. A comparative analysis of this data suggests that cardiac diastolic function is reduced after microgravity exposure with little or no change in systolic function as measured by ejection fraction However, the mechanisms responsible for these adaptations have not been determined. In this study, an integrative computer model of human physiology that forms the framework for the Digital Astronaut Project (Guyton/Coleman/Summers Model) was used in a systems analysis of the echocardiographic data in the context of general cardiovascular physiologic functioning. The physiologic mechanisms involved in the observed changes were then determined by a dissection of model interrelationships. The systems analysis of possible physiologic mechanisms involved reveals that a loss of fluid from the myocardial interstitial space may lead to a stiffening of the myocardium and could potentially result in some of the cardiac diastolic dysfunction seen postflight. The cardiovascular dynamics may be different during spaceflight.

  15. Long duration exposure facility post-flight thermal analysis, part 1

    NASA Technical Reports Server (NTRS)

    Berrios, William M.; Sampair, Thomas R.

    1992-01-01

    Results of the post-flight thermal analysis of the Long Duration Exposure Facility (LDEF) mission are presented. The LDEF mission thermal analysis was verified by comparing the thermal model results to flight data from the LDEF Thermal Measurements System (THERM). Post-flight calculated temperature uncertainties have been reduced to under +/- 18 F from the pre-flight uncertainties of +/- 40 F. The THERM consisted of eight temperature sensors, a shared tape recorder, a standard LDEF flight battery, and an electronics control box. The temperatures were measured at selected locations on the LDEF structure interior during the first 390 days of flight and recorded for post-flight analysis. After the LDEF retrieval from Space on 12 Jan. 1990, the tape recorder was recovered from the spacecraft and the data reduced for comparison to the LDEF predicted temperatures. The LDEF mission temperatures were calculated prior to the LDEF deployment on 7 Apr. 1980, and updated after the LDEF retrieval with the following actual flight parameter data: including thermal fluxes, spacecraft attitudes, thermal coatings degradation, and contamination effects. All updated data used for the calculation of post-flight temperatures is also presented in this document.

  16. Long duration exposure facility post-flight thermal analysis, part 2

    NASA Technical Reports Server (NTRS)

    Berrios, William M.; Sampair, Thomas R.

    1992-01-01

    Results of the post-flight thermal analysis for the Long Duration Exposure Facility (LDEF) mission are presented. The LDEF mission thermal analysis was verified by comparing the thermal model results to flight data from the LDEF Thermal Measurements System (THERM). Post-flight calculated temperature uncertainties have been reduced to under +/- 18 F from the pre-flight uncertainties of +/- 40 F. The THERM consisted of eight temperature sensors, a shared tape recorder, a standard LDEF flight battery, and an electronics control box. The temperatures were measured at selected locations on the LDEF structure interior during the first 390 days of flight and recorded for post-flight analysis. After the LDEF retrieval from Space on 12 Jan. 1990, the tape recorder was recovered from the spacecraft and the data reduced for comparison to the LDEF predicted temperatures. The LDEF mission temperatures were calculated prior to the LDEF deployment on 7 Apr. 1980, and updated after the LDEF retrieval with the following actual flight parameter data: thermal fluxes, spacecraft attitudes, thermal coatings degradation, and contamination effects. All updated data used for calculation of post-flight temperatures is also presented in this document.

  17. Personal breathing zone exposures among hot-mix asphalt paving workers; preliminary analysis for trends and analysis of work practices that resulted in the highest exposure concentrations.

    PubMed

    Osborn, Linda V; Snawder, John E; Kriech, Anthony J; Cavallari, Jennifer M; McClean, Michael D; Herrick, Robert F; Blackburn, Gary R; Olsen, Larry D

    2013-01-01

    An exposure assessment of hot-mix asphalt (HMA) paving workers was conducted to determine which of four exposure scenarios impacted worker exposure and dose. Goals of this report are to present the personal-breathing zone (PBZ) data, discuss the impact of substituting the releasing/cleaning agent, and discuss work practices that resulted in the highest exposure concentration for each analyte. One-hundred-seven PBZ samples were collected from HMA paving workers on days when diesel oil was used as a releasing/cleaning agent. An additional 36 PBZ samples were collected on days when B-100 (100% biodiesel, containing no petroleum-derived products) was used as a substitute releasing/cleaning agent. Twenty-four PBZ samples were collected from a reference group of concrete workers, who also worked in outdoor construction but had no exposure to asphalt emissions. Background and field blank samples were also collected daily. Total particulates and the benzene soluble fraction were determined gravimetrically. Total organic matter was determined using gas chromatography (GC) with flame ionization detection and provided qualitative information about other exposure sources contributing to worker exposure besides asphalt emissions. Thirty-three individual polycyclic aromatic compounds (PACs) were determined using GC with time-of-flight mass spectrometry; results were presented as either the concentration of an individual PAC or a summation of the individual PACs containing either 2- to 3-rings or 4- to 6-rings. Samples were also screened for PACs containing 4- to 6-rings using fluorescence spectroscopy. Arithmetic means, medians, and box plots of the PBZ data were used to evaluate trends in the data. Box plots illustrating the diesel oil results were more variable than the B-100. Also, the highest diesel oil results were much higher in concentration than the highest B-100 results. An analysis of the highest exposure results and field notes revealed a probable association between

  18. Personal Breathing Zone Exposures among Hot-Mix Asphalt Paving Workers; Preliminary Analysis for Trends and Analysis of Work Practices That Resulted in the Highest Exposure Concentrations

    PubMed Central

    Osborn, Linda V.; Snawder, John E.; Kriech, Anthony J.; Cavallari, Jennifer M.; McClean, Michael D.; Herrick, Robert F.; Blackburn, Gary R.; Olsen, Larry D.

    2015-01-01

    An exposure assessment of hot-mix asphalt (HMA) paving workers was conducted to determine which of four exposure scenarios impacted worker exposure and dose. Goals of this report are to present the personal-breathing zone (PBZ) data, discuss the impact of substituting the releasing/cleaning agent, and discuss work practices that resulted in the highest exposure concentration for each analyte. One-hundred-seven PBZ samples were collected from HMA paving workers on days when diesel oil was used as a releasing/cleaning agent. An additional 36 PBZ samples were collected on days when B-100 (100% biodiesel, containing no petroleum-derived products) was used as a substitute releasing/cleaning agent. Twenty-four PBZ samples were collected from a reference group of concrete workers, who also worked in outdoor construction but had no exposure to asphalt emissions. Background and field blank samples were also collected daily. Total particulates and the benzene soluble fraction were determined gravimetrically. Total organic matter was determined using gas chromatography (GC) with flame ionization detection and provided qualitative information about other exposure sources contributing to worker exposure besides asphalt emissions. Thirty-three individual polycyclic aromatic compounds (PACs) were determined using GC with time-offlight mass spectrometry; results were presented as either the concentration of an individual PAC or a summation of the individual PACs containing either 2- to 3-rings or 4- to 6-rings. Samples were also screened for PACs containing 4- to 6-rings using fluorescence spectroscopy. Arithmetic means, medians, and box plots of the PBZ data were used to evaluate trends in the data. Box plots illustrating the diesel oil results were more variable than the B-100. Also, the highest diesel oil results were much higher in concentration than the highest B-100 results. An analysis of the highest exposure results and field notes revealed a probable association between

  19. A study on quantitative analysis of exposure dose caused by patient depending on time and distance in nuclear medicine examination

    NASA Astrophysics Data System (ADS)

    Kim, H. S.; Cho, J. H.; Shin, S. G.; Dong, K. R.; Chung, W. K.; Chung, J. E.

    2013-01-01

    This study evaluated possible actions that can help protect against and reduce radiation exposure by measuring the exposure dose for each type of isotope that is used frequently in nuclear medicine before performing numerical analysis of the effective half-life based on the measurement results. From July to August in 2010, the study targeted 10, 6 and 5 people who underwent an 18F-FDG (fludeoxyglucose) positron emission tomography (PET) scan, 99mTc-HDP bone scan, and 201Tl myocardial single-photon emission computed tomography (SPECT) scan, respectively, in the nuclear medicine department. After injecting the required medicine into the subjects, a survey meter was used to measure the dose depending on the distance from the heart and time elapsed. For the 18F-FDG PET scan, the dose decreased by approximately 66% at 90 min compared to that immediately after the injection and by 78% at a distance of 1 m compared to that at 0.3 m. In the 99mTc-HDP bone scan, the dose decreased by approximately 71% in 200 min compared to that immediately after the injection and by approximately 78% at a distance of 1 m compared to that at 0.3 m. In the 201Tl myocardial SPECT scan, the dose decreased by approximately 30% in 250 min compared to that immediately after the injection and by approximately 55% at a distance of 1 m compared to that at 0.3 m. In conclusion, the dose decreases by a large margin depending on the distance and time. In conclusion, this study measured the exposure doses by isotopes, distance from the heart and exposure time, and found that the doses were reduced significantly according the distance and the time.

  20. Comparative responses of sperm cells and embryos of Pacific oyster (Crassostrea gigas) to exposure to metolachlor and its degradation products.

    PubMed

    Mai, Huong; Gonzalez, Patrice; Pardon, Patrick; Tapie, Nathalie; Budzinski, Hélène; Cachot, Jérôme; Morin, Bénédicte

    2014-02-01

    Metolachlor is one of the most intensively used chloroacetanilide herbicides in agriculture. Consequently, it has been frequently detected in coastal waters as well as its major degradation products, metolachlor ethane sulfonic acid (MESA) and metolachlor oxanilic acid (MOA) which are encountered at higher concentrations than metolachlor. Although a few studies of metolachlor toxicity have been conducted on marine organisms, little is known about the environmental toxicity of metolachlor degradation products. In this study, the deleterious effects of metolachlor and its degradation products on spermatozoa and embryos of Crassostrea gigas have been compared using biomarkers of developmental defects, DNA damage and gene transcription levels. After 24h exposure, significant increases in the percentage of abnormal D-larvae and DNA damage were observed from 0.01 μg L(-1) for S-metolachlor and 0.1 μg L(-1) for MESA and MOA. Results showed that S-metolachlor was more embryotoxic and genotoxic than its degradation products. Oyster sperm was also very sensitive to metolachlor exposure and followed the pattern: metolachlor (0.01 μg L(-1))>MOA (0.1 μg L(-1))>MESA (1 μg L(-1)). Metolachlor and MESA mainly triggered variations in the transcription level of genes encoding proteins involved in oxidative stress responses (mitochondrial superoxide dismutase and catalase). Overall, no significant variation in transcription levels could be detected in C. gigas embryos exposed to MOA. This study demonstrates that metolachlor and its main degradation products have the potential to impact several steps of oyster development and therefore recruitment in coastal areas exposed to chronic inputs of pesticides.

  1. Comparative assessments of the effects of alcohol exposure on fetal brain development using optical coherence tomography and ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Sudheendran, Narendran; Bake, Shameena; Miranda, Rajesh C.; Larin, Kirill V.

    2013-02-01

    The developing fetal brain is vulnerable to a variety of environmental agents including maternal ethanol consumption. Preclinical studies on the development and amelioration of fetal teratology would be significantly facilitated by the application of high resolution imaging technologies like optical coherence tomography (OCT) and high-frequency ultrasound (US). This study investigates the ability of these imaging technologies to measure the effects of maternal ethanol exposure on brain development, ex vivo, in fetal mice. Pregnant mice at gestational day 12.5 were administered ethanol (3 g/Kg b.wt.) or water by intragastric gavage, twice daily for three consecutive days. On gestational day 14.5, fetuses were collected and imaged. Three-dimensional images of the mice fetus brains were obtained by OCT and high-resolution US, and the volumes of the left and right ventricles of the brain were measured. Ethanol-exposed fetuses exhibited a statistically significant, 2-fold increase in average left and right ventricular volumes compared with the ventricular volume of control fetuses, with OCT-derived measures of 0.38 and 0.18 mm3, respectively, whereas the boundaries of the fetal mouse lateral ventricles were not clearly definable with US imaging. Our results indicate that OCT is a useful technology for assessing ventriculomegaly accompanying alcohol-induced developmental delay. This study clearly demonstrated advantages of using OCT for quantitative assessment of embryonic development compared with US imaging.

  2. Constructing Predictive Estimates for Worker Exposure to Radioactivity During Decommissioning: Analysis of Completed Decommissioning Projects - Master Thesis

    SciTech Connect

    Dettmers, Dana Lee; Eide, Steven Arvid

    2002-10-01

    An analysis of completed decommissioning projects is used to construct predictive estimates for worker exposure to radioactivity during decommissioning activities. The preferred organizational method for the completed decommissioning project data is to divide the data by type of facility, whether decommissioning was performed on part of the facility or the complete facility, and the level of radiation within the facility prior to decommissioning (low, medium, or high). Additional data analysis shows that there is not a downward trend in worker exposure data over time. Also, the use of a standard estimate for worker exposure to radioactivity may be a best estimate for low complete storage, high partial storage, and medium reactor facilities; a conservative estimate for some low level of facility radiation facilities (reactor complete, research complete, pits/ponds, other), medium partial process facilities, and high complete research facilities; and an underestimate for the remaining facilities. Limited data are available to compare different decommissioning alternatives, so the available data are reported and no conclusions can been drawn. It is recommended that all DOE sites and the NRC use a similar method to document worker hours, worker exposure to radiation (person-rem), and standard industrial accidents, injuries, and deaths for all completed decommissioning activities.

  3. Assessing and reporting uncertainties in dietary exposure analysis: Mapping of uncertainties in a tiered approach.

    PubMed

    Kettler, Susanne; Kennedy, Marc; McNamara, Cronan; Oberdörfer, Regina; O'Mahony, Cian; Schnabel, Jürgen; Smith, Benjamin; Sprong, Corinne; Faludi, Roland; Tennant, David

    2015-08-01

    Uncertainty analysis is an important component of dietary exposure assessments in order to understand correctly the strength and limits of its results. Often, standard screening procedures are applied in a first step which results in conservative estimates. If through those screening procedures a potential exceedance of health-based guidance values is indicated, within the tiered approach more refined models are applied. However, the sources and types of uncertainties in deterministic and probabilistic models can vary or differ. A key objective of this work has been the mapping of different sources and types of uncertainties to better understand how to best use uncertainty analysis to generate more realistic comprehension of dietary exposure. In dietary exposure assessments, uncertainties can be introduced by knowledge gaps about the exposure scenario, parameter and the model itself. With this mapping, general and model-independent uncertainties have been identified and described, as well as those which can be introduced and influenced by the specific model during the tiered approach. This analysis identifies that there are general uncertainties common to point estimates (screening or deterministic methods) and probabilistic exposure assessment methods. To provide further clarity, general sources of uncertainty affecting many dietary exposure assessments should be separated from model-specific uncertainties.

  4. Occupational Exposure to Endocrine-Disrupting Chemicals and Birth Weight and Length of Gestation: A European Meta-Analysis

    PubMed Central

    Birks, Laura; Casas, Maribel; Garcia, Ana M.; Alexander, Jan; Barros, Henrique; Bergström, Anna; Bonde, Jens Peter; Burdorf, Alex; Costet, Nathalie; Danileviciute, Asta; Eggesbø, Merete; Fernández, Mariana F.; González-Galarzo, M. Carmen; Hanke, Wojciech; Jaddoe, Vincent; Kogevinas, Manolis; Kull, Inger; Lertxundi, Aitana; Melaki, Vasiliki; Andersen, Anne-Marie Nybo; Olea, Nicolás; Polanska, Kinga; Rusconi, Franca; Santa-Marina, Loreto; Santos, Ana Cristina; Vrijkotte, Tanja; Zugna, Daniela; Nieuwenhuijsen, Mark; Cordier, Sylvaine; Vrijheid, Martine

    2016-01-01

    Background: Women of reproductive age can be exposed to endocrine-disrupting chemicals (EDCs) at work, and exposure to EDCs in pregnancy may affect fetal growth. Objectives: We assessed whether maternal occupational exposure to EDCs during pregnancy as classified by application of a job exposure matrix was associated with birth weight, term low birth weight (LBW), length of gestation, and preterm delivery. Methods: Using individual participant data from 133,957 mother–child pairs in 13 European cohorts spanning births from 1994 through 2011, we linked maternal job titles with exposure to 10 EDC groups as assessed through a job exposure matrix. For each group, we combined the two levels of exposure categories (possible and probable) and compared birth outcomes with the unexposed group (exposure unlikely). We performed meta-analyses of cohort-specific estimates. Results: Eleven percent of pregnant women were classified as exposed to EDCs at work during pregnancy, based on job title. Classification of exposure to one or more EDC group was associated with an increased risk of term LBW [odds ratio (OR) = 1.25; 95% CI: 1.04, 1.49], as were most specific EDC groups; this association was consistent across cohorts. Further, the risk increased with increasing number of EDC groups (OR = 2.11; 95% CI: 1.10, 4.06 for exposure to four or more EDC groups). There were few associations (p < 0.05) with the other outcomes; women holding job titles classified as exposed to bisphenol A or brominated flame retardants were at higher risk for longer length of gestation. Conclusion: Results from our large population-based birth cohort design indicate that employment during pregnancy in occupations classified as possibly or probably exposed to EDCs was associated with an increased risk of term LBW. Citation: Birks L, Casas M, Garcia AM, Alexander J, Barros H, Bergström A, Bonde JP, Burdorf A, Costet N, Danileviciute A, Eggesbø M, Fernández MF, González-Galarzo MC, Gražulevičienė R

  5. Analysis of personal and bedroom exposure to ELF-MFs in children in Italy and Switzerland.

    PubMed

    Struchen, Benjamin; Liorni, Ilaria; Parazzini, Marta; Gängler, Stephanie; Ravazzani, Paolo; Röösli, Martin

    2016-11-01

    Little is known about the real everyday exposure of children in Europe to extremely low-frequency magnetic fields (ELF-MFs). The aims of this study are to (i) assess personal ELF-MF exposure in children; (ii) to identify factors determining personal and bedroom ELF-MF exposure measurements in children; (iii) to evaluate the reproducibility of exposure summary measures; and (iv) to compare personal with bedroom measurements. In Switzerland and Italy, 172 children aged between 5 and 13 years were equipped with ELF-MF measurement devices (EMDEX II, measuring 40-800 Hz) during 24-72 h twice, in the warm and the cold season. In addition, 24-h measurements were taken in the bedroom of children. In our study, sample geometric mean ELF-MF exposure was 0.04 μT for personal and 0.05 μT for bedroom measurements. Living within 100 m of a highest voltage power line increased geometric mean personal exposure by a factor of 3.3, and bedroom measurements by a factor 6.8 compared to a control group. Repeated measurements within the same subject showed high reproducibility for the geometric mean (Spearman's correlation 0.78 for personal and 0.86 for bedroom measurements) but less for the 95th and 99th percentile of the personal measurements (≤0.42). Spearman's correlation between bedroom and personal exposure was 0.86 for the geometric mean but considerably lower for the 95th and 99th percentiles (≤0.60). Most previous studies on ELF-MF childhood leukaemia used mean bedroom exposure. Our study demonstrates that geometric mean bedroom measurements is well correlated with personal geometric mean exposure, and has high temporal reproducibility.

  6. Joint analysis of three European nested case-control studies of lung cancer among radon exposed miners: exposure restricted to below 300 WLM.

    PubMed

    Hunter, Nezahat; Muirhead, Colin R; Tomasek, Ladislav; Kreuzer, Michaela; Laurier, Dominique; Leuraud, Klervi; Schnelzer, Maria; Grosche, Bernd; Placek, Vit; Heribanova, Alena; Timarche, Margot

    2013-03-01

    Analyses of lung cancer risk were carried out using restrictions to nested case-control data on uranium miners in the Czech Republic, France, and Germany. With the data restricted to cumulative exposures below 300 working-level-months (WLM) and adjustment for smoking status, the excess relative risk (ERR) per WLM was 0.0174 (95% CI: 0.009-0.035), compared to the estimate of 0.008 (95% CI: 0.004-0.014) using the unrestricted data. Analysis of both the restricted and unrestricted data showed that time since exposure windows had a major effect; the ERR/WLM was six times higher for more recent exposures (5-24 y) than for more distant exposures (25 y or more). Based on a linear model fitted to data on exposures <300 WLM, the ERR WLM of lung cancer at 30 y after exposure was estimated to be 0.021 (95% CI: 0.011-0.040), and the risks decreased by 47% per decade increase in time since exposure. The results from analyzing the joint effects of radon and smoking were consistent with a sub-multiplicative interaction; the ERR WLM was greater for non-smokers compared with current or ex-smokers, although there was no statistically significant variation in the ERR WLM by smoking status. The patterns of risk with radon exposure from the combined European nested case-control miner analysis were generally consistent with those based on the BEIR VI Exposure-Age-Concentration model. Based on conversions from WLM to time weighted averaged radon concentration (expressed per 100 Bq m), the results from this analysis of miner data were in agreement with those from the joint analysis of the European residential radon studies.

  7. Meta-analysis on occupational exposure to pesticides--neurobehavioral impact and dose-response relationships.

    PubMed

    Meyer-Baron, Monika; Knapp, Guido; Schäper, Michael; van Thriel, Christoph

    2015-01-01

    While the health impact of high exposures to pesticides is acknowledged, the impact of chronic exposures in the absence of acute poisonings is controversial. A systematic analysis of dose-response relationships is still missing. Its absence may provoke alternative explanations for altered performances. Consequently, opportunities for health prevention in the occupational and environmental field may be missed. Objectives were (1) quantification of the neurotoxic impact of pesticides by an analysis of functional alterations in workers measured by neuropsychological performance tests, (2) estimates of dose-response relationships on the basis of exposure duration, and (3) exploration of susceptible subgroups. The meta-analysis employed a random effects model to obtain overall effects for individual performance tests. Twenty-two studies with a total of 1758 exposed and 1260 reference individuals met the inclusion criteria. At least three independent outcomes were available for twenty-six performance variables. Significant performance effects were shown in adults and referred to both cognitive and motor performances. Effect sizes ranging from dRE=-0.14 to dRE=-0.67 showed consistent outcomes for memory and attention. Relationships between effect sizes and exposure duration were indicated for individual performance variables and the total of measured performances. Studies on adolescents had to be analyzed separately due to numerous outliers. The large variation among outcomes hampered the analysis of the susceptibility in this group, while data on female workers was too scant for the analysis. Relationships exist between the impact of pesticides on performances and exposure duration. A change in test paradigms would help to decipher the impact more specifically. The use of biomarkers appropriate for lower exposures would allow a better prevention of neurotoxic effects due to occupational and environmental exposure. Intervention studies in adolescents seem warranted to

  8. Comparing Urinary Biomarkers of Airborne and Dermal Exposure to Polycyclic Aromatic Compounds in Asphalt-Exposed Workers

    PubMed Central

    Sobus, Jon R.; McClean, Michael D.; Herrick, Robert F.; Waidyanatha, Suramya; Nylander-French, Leena A.; Kupper, Lawrence L.; Rappaport, Stephen M.

    2009-01-01

    When working with hot mix asphalt, road pavers are exposed to polycyclic aromatic hydrocarbons (PAHs) through the inhalation of vapors and particulate matter (PM) and through dermal contact with PM and contaminated surfaces. Several PAHs with four to six rings are potent carcinogens which reside in these particulate emissions. Since urinary biomarkers of large PAHs are rarely detectable in asphalt workers, attention has focused upon urinary levels of the more volatile and abundant two-ring and three-ring PAHs as potential biomarkers of PAH exposure. Here, we compare levels of particulate polycyclic aromatic compounds (P-PACs, a group of aromatic hydrocarbons containing PAHs and heterocyclic compounds with four or more rings) in air and dermal patch samples from 20 road pavers to the corresponding urinary levels of naphthalene (U-Nap) (two rings), phenanthrene (U-Phe) (three rings), monohydroxylated metabolites of naphthalene (OH-Nap) and phenanthrene (OH-Phe), and 1-hydroxypyrene (OH-Pyr) (four rings), the most widely used biomarker of PAH exposure. For each worker, daily breathing-zone air (n = 55) and dermal patch samples (n = 56) were collected on three consecutive workdays along with postshift, bedtime, and morning urine samples (n = 149). Measured levels of P-PACs and the urinary analytes were used to statistically model exposure–biomarker relationships while controlling for urinary creatinine, smoking status, age, body mass index, and the timing of urine sampling. Levels of OH-Phe in urine collected postshift, at bedtime, and the following morning were all significantly associated with levels of P-PACs in air and dermal patch samples. For U-Nap, U-Phe, and OH-Pyr, both air and dermal patch measurements of P-PACs were significant predictors of postshift urine levels, and dermal patch measurements were significant predictors of bedtime urine levels (all three analytes) and morning urine levels (U-Nap and OH-Pyr only). Significant effects of

  9. Multiple-exposure photographic analysis of a motile spirochete.

    PubMed Central

    Goldstein, S F; Charon, N W

    1990-01-01

    The Leptospiraceae are thin spirochetes with a unique mode of motility. These spiral-shaped bacteria have internal periplasmic flagella that propel the cells in low-viscosity and gel-like high-viscosity media. A model of Leptospiraceae motility has been previously proposed that states that the subterminally attached periplasmic flagella rotate between the outer sheath and the helical protoplasmic cylinder. The shape of the cell ends and the direction of gyration of these ends are determined by the direction of rotation of the internal periplasmic flagella. Rotation of the periplasmic flagella in one direction causes that end to be spiral-shaped, and rotation in the other direction causes that end to be hook-shaped. One prediction of the model is that these right-handed spirochetes roll clockwise when swimming away from an observer. For maximum swimming efficiency, the model predicts that the sense of the spiral-shaped end is left-handed and gyrates counterclockwise. The present study presents direct evidence that the cell rolls clockwise (protoplasmic cylinder helix diameter = 0.24 micron; pitch = 0.69 micron), the ends gyrate counterclockwise, and the spiral-shaped end is left-handed (helix diameter = 0.6 micron; pitch = 2.7 microns)--as predicted by the model. The hook-shaped end appears approximately planar. The approach used was to illuminate stroboscopically cells slowed by Ficoll and analyze the resultant multiple-exposure photographs focused above and below the axis of the cell. The methodology used should be helpful in analyzing the motility of the larger and more complex spirochetes. Images PMID:2367518

  10. NATIONAL HUMAN EXPOSURE ASSESSMENT SURVEY (NHEXAS): ANALYSIS OF EXPOSURE PATHWAYS AND ROUTES FOR ARSENIC AND LEAD IN EPA REGION 5

    EPA Science Inventory

    The National Human Exposure Assessment Survey (NHEXAS) Phase I field study conducted in EPA Region 5 (Great Lakes Area) provides extensive exposure data on a representative sample of approximately 250 residents of the region. Associated environmental media and biomarker (blood...

  11. A Bayesian analysis of uncertainties on lung doses resulting from occupational exposures to uranium.

    PubMed

    Puncher, M; Birchall, A; Bull, R K

    2013-09-01

    In a recent epidemiological study, Bayesian estimates of lung doses were calculated in order to determine a possible association between lung dose and lung cancer incidence resulting from occupational exposures to uranium. These calculations, which produce probability distributions of doses, used the human respiratory tract model (HRTM) published by the International Commission on Radiological Protection (ICRP) with a revised particle transport clearance model. In addition to the Bayesian analyses, point estimates (PEs) of doses were also provided for that study using the existing HRTM as it is described in ICRP Publication 66. The PEs are to be used in a preliminary analysis of risk. To explain the differences between the PEs and Bayesian analysis, in this paper the methodology was applied to former UK nuclear workers who constituted a subset of the study cohort. The resulting probability distributions of lung doses calculated using the Bayesian methodology were compared with the PEs obtained for each worker. Mean posterior lung doses were on average 8-fold higher than PEs and the uncertainties on doses varied over a wide range, being greater than two orders of magnitude for some lung tissues. It is shown that it is the prior distributions of the parameters describing absorption from the lungs to blood that are responsible for the large difference between posterior mean doses and PEs. Furthermore, it is the large prior uncertainties on these parameters that are mainly responsible for the large uncertainties on lung doses. It is concluded that accurate determination of the chemical form of inhaled uranium, as well as the absorption parameter values for these materials, is important for obtaining unbiased estimates of lung doses from occupational exposures to uranium for epidemiological studies. Finally, it should be noted that the inferences regarding the PEs described here apply only to the assessments of cases provided for the epidemiological study, where central

  12. Exposure Measurement Error in PM2.5 Health Effects Studies: A Pooled Analysis of Eight Personal Exposure Validation Studies

    EPA Science Inventory

    Background: Exposure measurement error is a concern in long-term PM2.5 health studies using ambient concentrations as exposures. We assessed error magnitude by estimating calibration coefficients as the association between personal PM2.5 exposures from validation studies and typ...

  13. Selenium Exposure and Cancer Risk: an Updated Meta-analysis and Meta-regression

    PubMed Central

    Cai, Xianlei; Wang, Chen; Yu, Wanqi; Fan, Wenjie; Wang, Shan; Shen, Ning; Wu, Pengcheng; Li, Xiuyang; Wang, Fudi

    2016-01-01

    The objective of this study was to investigate the associations between selenium exposure and cancer risk. We identified 69 studies and applied meta-analysis, meta-regression and dose-response analysis to obtain available evidence. The results indicated that high selenium exposure had a protective effect on cancer risk (pooled OR = 0.78; 95%CI: 0.73–0.83). The results of linear and nonlinear dose-response analysis indicated that high serum/plasma selenium and toenail selenium had the efficacy on cancer prevention. However, we did not find a protective efficacy of selenium supplement. High selenium exposure may have different effects on specific types of cancer. It decreased the risk of breast cancer, lung cancer, esophageal cancer, gastric cancer, and prostate cancer, but it was not associated with colorectal cancer, bladder cancer, and skin cancer. PMID:26786590

  14. Selenium Exposure and Cancer Risk: an Updated Meta-analysis and Meta-regression.

    PubMed

    Cai, Xianlei; Wang, Chen; Yu, Wanqi; Fan, Wenjie; Wang, Shan; Shen, Ning; Wu, Pengcheng; Li, Xiuyang; Wang, Fudi

    2016-01-20

    The objective of this study was to investigate the associations between selenium exposure and cancer risk. We identified 69 studies and applied meta-analysis, meta-regression and dose-response analysis to obtain available evidence. The results indicated that high selenium exposure had a protective effect on cancer risk (pooled OR = 0.78; 95%CI: 0.73-0.83). The results of linear and nonlinear dose-response analysis indicated that high serum/plasma selenium and toenail selenium had the efficacy on cancer prevention. However, we did not find a protective efficacy of selenium supplement. High selenium exposure may have different effects on specific types of cancer. It decreased the risk of breast cancer, lung cancer, esophageal cancer, gastric cancer, and prostate cancer, but it was not associated with colorectal cancer, bladder cancer, and skin cancer.

  15. Exposure to UV radiation and risk of Hodgkin lymphoma: a pooled analysis

    PubMed Central

    Glaser, Sally L.; Schupp, Clayton W.; Ekström Smedby, Karin; de Sanjosé, Silvia; Kane, Eleanor; Melbye, Mads; Forétova, Lenka; Maynadié, Marc; Staines, Anthony; Becker, Nikolaus; Nieters, Alexandra; Brennan, Paul; Boffetta, Paolo; Cocco, Pierluigi; Glimelius, Ingrid; Clavel, Jacqueline; Hjalgrim, Henrik; Chang, Ellen T.

    2013-01-01

    Ultraviolet radiation (UVR) exposure has been inversely associated with Hodgkin lymphoma (HL) risk, but only inconsistently, only in a few studies, and without attention to HL heterogeneity. We conducted a pooled analysis of HL risk focusing on type and timing of UVR exposure and on disease subtypes by age, histology, and tumor-cell Epstein-Barr virus (EBV) status. Four case-control studies contributed 1320 HL cases and 6381 controls. We estimated lifetime, adulthood, and childhood UVR exposure and history of sunburn and sunlamp use. We used 2-stage estimation with mixed-effects models and weighted pooled effect estimates by inverse marginal variances. We observed statistically significant inverse associations with HL risk for UVR exposures during childhood and adulthood, sunburn history, and sunlamp use, but we found no significant dose-response relationships. Risks were significant only for EBV-positive HL (pooled odds ratio, 0.56; 95% confidence interval, 0.35 to 0.91 for the highest overall UVR exposure category), with a significant linear trend for overall exposure (P = .03). Pooled relative risk estimates were not heterogeneous across studies. Increased UVR exposure may protect against HL, particularly EBV-positive HL. Plausible mechanisms involving UVR induction of regulatory T cells or the cellular DNA damage response suggest opportunities for new prevention targets. PMID:24016459

  16. Meta-analysis of residential exposure to radon gas and lung cancer.

    PubMed Central

    Pavia, Maria; Bianco, Aida; Pileggi, Claudia; Angelillo, Italo F.

    2003-01-01

    OBJECTIVES: To investigate the relation between residential exposure to radon and lung cancer. METHODS: A literature search was performed using Medline and other sources. The quality of studies was assessed. Adjusted odds ratios with 95% confidence intervals (CI) for the risk of lung cancer among categories of levels of exposure to radon were extracted. For each study, a weighted log-linear regression analysis of the adjusted odds ratios was performed according to radon concentration. The random effect model was used to combine values from single studies. Separate meta-analyses were performed on results from studies grouped with similar characteristics or with quality scores above or equal to the median. FINDINGS: Seventeen case-control studies were included in the meta-analysis. Quality scoring for individual studies ranged from 0.45 to 0.77 (median, 0.64). Meta-analysis based on exposure at 150 Bq/m3 gave a pooled odds ratio estimate of 1.24 (95% CI, 1.11-1.38), which indicated a potential effect of residential exposure to radon on the risk of lung cancer. Pooled estimates of fitted odds ratios at several levels of randon exposure were all significantly different from unity--ranging from 1.07 at 50 Bq/m3 to 1.43 at 250 Bq/m3. No remarkable differences from the baseline analysis were found for odds ratios from sensitivity analyses of studies in which > 75% of eligible cases were recruited (1.12, 1.00-1.25) and studies that included only women (1.29, 1.04-1.60). CONCLUSION: Although no definitive conclusions may be drawn, our results suggest a dose-response relation between residential exposure to radon and the risk of lung cancer. They support the need to develop strategies to reduce human exposure to radon. PMID:14758433

  17. SURROGATE TISSUE ANALYSIS: MONITORING TOXICANT EXPOSURE AND HEALTH STATUS OF INACCESSIBLE TISSUES THROUGH THE ANALYSIS OF ACCESSIBLE TISSUES AND CELLS

    EPA Science Inventory

    Surrogate Tissue Analysis: Monitoring Toxicant Exposure And Health Status Of Inaccessible Tissues Through The Analysis Of Accessible Tissues And Cells*
    John C. Rockett1, Michael E. Burczynski 2, Albert J. Fornace, Jr.3, Paul.C. Herrmann4, Stephen A. Krawetz5, and David J. Dix1...

  18. Comparative and Familial Analysis of Handedness in Great Apes

    PubMed Central

    Hopkins, William D.

    2007-01-01

    Historically, population-level handedness has been considered a hallmark of human evolution. Whether nonhuman primates exhibit population-level handedness remains a topic of considerable debate. This paper summarizes published data on handedness in great apes. Comparative analysis indicated that chimpanzees and bonobos show population-level right handedness, whereas gorillas and orangutans do not. All ape species showed evidence of population-level handedness when considering specific tasks. Familial analyses in chimpanzees indicated that offspring and maternal (but not paternal) handedness was significantly positively correlated, but this finding was contingent upon the classification criteria used to evaluate hand preference. Overall, the proportion of right handedness is lower in great apes compared with humans, and various methodological and theoretical explanations for this discrepancy are discussed. PMID:16822166

  19. Stigma, sex work, and substance use: a comparative analysis.

    PubMed

    Benoit, Cecilia; McCarthy, Bill; Jansson, Mikael

    2015-03-01

    Stigma is a widely used concept in social science research and an extensive literature claims that stigmatisation contributes to numerous negative health outcomes. However, few studies compare groups that vary in the extent to which they are stigmatised and even fewer studies examine stigma's independent and mediating effects. This article addresses these gaps in a comparative study of perceived stigma and drug use among three low-income feminised service occupations: sex work, food and alcoholic beverage serving, and barbering and hairstyling. An analysis of longitudinal data shows positive associations between sex work, perceived stigma, and socially less acceptable drug use (for example, heroin and cocaine), and that stigma mediates part of the link between sex work and the use of these drugs. Our overall findings suggest that perceived stigma is pronounced among those who work in the sex industry and negatively affects health independently of sex work involvement.

  20. Sequence and comparative analysis of Leuconostoc dairy bacteriophages.

    PubMed

    Kot, Witold; Hansen, Lars H; Neve, Horst; Hammer, Karin; Jacobsen, Susanne; Pedersen, Per D; Sørensen, Søren J; Heller, Knut J; Vogensen, Finn K

    2014-04-17

    Bacteriophages attacking Leuconostoc species may significantly influence the quality of the final product. There is however limited knowledge of this group of phages in the literature. We have determined the complete genome sequences of nine Leuconostoc bacteriophages virulent to either Leuconostoc mesenteroides or Leuconostoc pseudomesenteroides strains. The phages have dsDNA genomes with sizes ranging from 25.7 to 28.4 kb. Comparative genomics analysis helped classify the 9 phages into two classes, which correlates with the host species. High percentage of similarity within the classes on both nucleotide and protein levels was observed. Genome comparison also revealed very high conservation of the overall genomic organization between the classes. The genes were organized in functional modules responsible for replication, packaging, head and tail morphogenesis, cell lysis and regulation and modification, respectively. No lysogeny modules were detected. To our knowledge this report provides the first comparative genomic work done on Leuconostoc dairy phages.

  1. Comparative analysis of NDE techniques with image processing

    NASA Astrophysics Data System (ADS)

    Rathod, Vijay R.; Anand, R. S.; Ashok, Alaknanda

    2012-12-01

    The paper reports comparative results of nondestructive testing (NDT) based experimentation done on created flaws in the casting at the Central Foundry Forge Plant (CFFP) of Bharat Heavy Electrical Ltd. India (BHEL). The present experimental study is aimed at comparing the evaluation of image processing methods applied on the radiographic images of welding defects such as slag inclusion, porosity, lack-of-root penetration and cracks with other NDT methods. Different image segmentation techniques have been proposed here for identifying the above created welding defects. Currently, there is a large amount of research work going on in the field of automated system for inspection, analysis and detection of flaws in the weldments. Comparison of other NDT methods and application of image processing on the radiographic images of weld defects are aimed to detect defects reliably and to make accept/reject decisions as per the international standard.

  2. Prevalence of exposure to suicide: A meta-analysis of population-based studies.

    PubMed

    Andriessen, Karl; Rahman, Bayzidur; Draper, Brian; Dudley, Michael; Mitchell, Philip B

    2017-05-01

    Those exposed to suicide are at increased risk of adverse outcomes including mental illness, impaired social functioning, and fatal and non-fatal suicidal behavior. However, it is unclear how many people are exposed to suicide in the general community. This first meta-analysis of population-based studies aimed to provide pooled estimates of past-year and lifetime prevalence of exposure to suicide among family, friends/peers, and all relationships. In addition, the study examined prevalence of exposure to suicide by age group: adolescents and adults. Systematic searches of the literature in Embase, Medline and PsycINFO identified eighteen studies that were included in the analysis. Pooled past-year prevalence was 4.31% (CI: 2.50 to 6.58) and life-time prevalence 21.83% (CI: 16.32 to 27.90). Both past-year and lifetime prevalences of exposure to suicide among friends and peers were significantly higher than the prevalence of exposure within families; there were no differences in the prevalence of exposure to suicide between adolescents and adults. Heterogeneity was highly significant. Future research should be conducted with large national representative samples and use standardised assessment instruments. Given the increased risks of adverse outcomes among those exposed to suicide, the high rate of exposure to suicide reported here has important ramifications for public health and mental health service delivery.

  3. Initial sequencing and comparative analysis of the mouse genome

    SciTech Connect

    Waterston, Robert H.; Lindblad-Toh, Kerstin; Birney, Ewan; Rogers, Jane; Abril, Josep F.; Agarwal, Pankaj; Agarwala, Richa; Ainscough, Rachel; Alexandersson, Marina; An, Peter; Antonarakis, Stylianos E.; Attwood, John; Baertsch, Robert; Bailey, Jonathon; Barlow, Karen; Beck, Stephan; Berry, Eric; Birren, Bruce; Bloom, Toby; Bork, Peer; Botcherby, Marc; Bray, Nicolas; Brent, Michael R.; Brown, Daniel G.; Brown, Stephen D.; Bult, Carol; Burton, John; Butler, Jonathan; Campbell, Robert D.; Carninci, Piero; Cawley, Simon; Chiaromonte, Francesca; Chinwalla, Asif T.; Church, Deanna M.; Clamp, Michele; Clee, Christopher; Collins, Francis S.; Cook, Lisa L.; Copley, Richard R.; Coulson, Alan; Couronne, Olivier; Cuff, James; Curwen, Val; Cutts, Tim; Daly, Mark; David, Robert; Davies, Joy; Delehaunty, Kimberly D.; Deri, Justin; Dermitzakis, Emmanouil T.; Dewey, Colin; Dickens, Nicholas J.; Diekhans, Mark; Dodge, Sheila; Dubchak, Inna; Dunn, Diane M.; Eddy, Sean R.; Elnitski, Laura; Emes, Richard D.; Eswara, Pallavi; Eyras, Eduardo; Felsenfeld, Adam; Fewell, Ginger A.; Flicek, Paul; Foley, Karen; Frankel, Wayne N.; Fulton, Lucinda A.; Fulton, Robert S.; Furey, Terrence S.; Gage, Diane; Gibbs, Richard A.; Glusman, Gustavo; Gnerre, Sante; Goldman, Nick; Goodstadt, Leo; Grafham, Darren; Graves, Tina A.; Green, Eric D.; Gregory, Simon; Guigo, Roderic; Guyer, Mark; Hardison, Ross C.; Haussler, David; Hayashizaki, Yoshihide; Hillier, LaDeana W.; Hinrichs, Angela; Hlavina, Wratko; Holzer, Timothy; Hsu, Fan; Hua, Axin; Hubbard, Tim; Hunt, Adrienne; Jackson, Ian; Jaffe, David B.; Johnson, L. Steven; Jones, Matthew; Jones, Thomas A.; Joy, Ann; Kamal, Michael; Karlsson, Elinor K.; Karolchik, Donna; Kasprzyk, Arkadiusz; Kawai, Jun; Keibler, Evan; Kells, Cristyn; Kent, W. James; Kirby, Andrew; Kolbe, Diana L.; Korf, Ian; Kucherlapati, Raju S.; Kulbokas III, Edward J.; Kulp, David; Landers, Tom; Leger, J.P.; Leonard, Steven; Letunic, Ivica; Levine, Rosie; et al.

    2002-12-15

    The sequence of the mouse genome is a key informational tool for understanding the contents of the human genome and a key experimental tool for biomedical research. Here, we report the results of an international collaboration to produce a high-quality draft sequence of the mouse genome. We also present an initial comparative analysis of the mouse and human genomes, describing some of the insights that can be gleaned from the two sequences. We discuss topics including the analysis of the evolutionary forces shaping the size, structure and sequence of the genomes; the conservation of large-scale synteny across most of the genomes; the much lower extent of sequence orthology covering less than half of the genomes; the proportions of the genomes under selection; the number of protein-coding genes; the expansion of gene families related to reproduction and immunity; the evolution of proteins; and the identification of intraspecies polymorphism.

  4. Establishing a framework for comparative analysis of genome sequences

    SciTech Connect

    Bansal, A.K.

    1995-06-01

    This paper describes a framework and a high-level language toolkit for comparative analysis of genome sequence alignment The framework integrates the information derived from multiple sequence alignment and phylogenetic tree (hypothetical tree of evolution) to derive new properties about sequences. Multiple sequence alignments are treated as an abstract data type. Abstract operations have been described to manipulate a multiple sequence alignment and to derive mutation related information from a phylogenetic tree by superimposing parsimonious analysis. The framework has been applied on protein alignments to derive constrained columns (in a multiple sequence alignment) that exhibit evolutionary pressure to preserve a common property in a column despite mutation. A Prolog toolkit based on the framework has been implemented and demonstrated on alignments containing 3000 sequences and 3904 columns.

  5. [Comparative analysis of spatial organization of myoglobins. II. Secondary structure].

    PubMed

    Korobov, V N; Nazarenko, V I; Radomskiĭ, N F; Starodub, N F

    1992-01-01

    An analysis of probability of distribution curves of alpha-helical sites and bends of polypeptide chains of myoglobins in half-water mammals (beaver, nutria, muskrat, otter) carried out in comparison with those of myoglobins of the horse and Sperm whale (X-ray diffraction analysis has revealed their tertiary structure) has revealed a coincidence of the secondary structure sites end bends of the chain in the studied respiratory hemoproteins of muscles. Despite a considerable number of amino acid substitutions the profiles of alpha-helicity and B-bends of the compared proteins are practically identical. This indicates to the "resistance" of the probability curves to amino acid substitutions and to retention of the tertiary structure of myoglobins in evolutionary remote species of the animals.

  6. A comparative analysis of Media Lengua and Quichua vowel production.

    PubMed

    Stewart, Jesse

    2014-01-01

    This study presents a comparative analysis of F1 and F2 vowel frequencies from Pijal Media Lengua (PML) and Imbabura Quichua. Mixed-effects models are used to test Spanish-derived high and low vowels against their Quichua-derived counterparts for statistical significance. Spanish-derived and Quichua-derived high vowels are also tested against Spanish-derived mid vowels. This analysis suggests that PML may be manipulating as many as eight vowels where Spanishderived high and low vowels coexist as near-mergers with their Quichua-derived counterparts, while high and mid vowels coexist with partial overlap. Quichua, traditionally viewed as a three-vowel system, shows similar results and may be manipulating as many as six vowels.

  7. Comparative analysis of nonverbal interpersonal communication of schizophrenics and normals.

    PubMed

    Hardin, S B

    1980-06-01

    The nonverbal communications of schizophrenics and normals in dyadic interactions were analyzed and compared. Twelve purposively selected women were videotaped in normal-normal, normal-schizophrenic, and schizophrenic-schizophrenic communication acts for 30 minutes. Using a PLATO IV computer program and a modified Kendon Kinesic Notation System, a priori sets of nonverbal behaviors were recorded at 1-second intervals. Frequency and duration scores for the sets of nonverbal behaviors with corresponding communication meanings were totaled. A nested analysis of variance showed that the three groups differed significantly (p less than .05) in engagement and defensiveness and that the normal interactors were the least imitative of the three groups. An analysis and description of the patterns of nonverbal communication also revealed differences, lending support to the theory of dysjunctive schizophrenic communication.

  8. Feature-level sentiment analysis by using comparative domain corpora

    NASA Astrophysics Data System (ADS)

    Quan, Changqin; Ren, Fuji

    2016-06-01

    Feature-level sentiment analysis (SA) is able to provide more fine-grained SA on certain opinion targets and has a wider range of applications on E-business. This study proposes an approach based on comparative domain corpora for feature-level SA. The proposed approach makes use of word associations for domain-specific feature extraction. First, we assign a similarity score for each candidate feature to denote its similarity extent to a domain. Then we identify domain features based on their similarity scores on different comparative domain corpora. After that, dependency grammar and a general sentiment lexicon are applied to extract and expand feature-oriented opinion words. Lastly, the semantic orientation of a domain-specific feature is determined based on the feature-oriented opinion lexicons. In evaluation, we compare the proposed method with several state-of-the-art methods (including unsupervised and semi-supervised) using a standard product review test collection. The experimental results demonstrate the effectiveness of using comparative domain corpora.

  9. Radiation Exposure Effects and Shielding Analysis of Carbon Nanotube Materials

    NASA Technical Reports Server (NTRS)

    Wilkins, Richard; Armendariz, Lupita (Technical Monitor)

    2002-01-01

    Carbon nanotube materials promise to be the basis for a variety of emerging technologies with aerospace applications. Potential applications to human space flight include spacecraft shielding, hydrogen storage, structures and fixtures and nano-electronics. Appropriate risk analysis on the properties of nanotube materials is essential for future mission safety. Along with other environmental hazards, materials used in space flight encounter a hostile radiation environment for all mission profiles, from low earth orbit to interplanetary space.

  10. Comparative biomorphologic analysis about three dentinal adhesives of last generations.

    PubMed

    Carini, F; Varia, P; Valenza, V

    2001-01-01

    The aim of this work consists in a comparative biomorphological analysis of the properties of infiltration and of adhesion to dental tissues of three among the more used enamel dentinal adhesives of the last generation known with the commercial name of Syntac, Excite and Prompt. The results have given evidence that Syntac has got short adhesion, Excite has got good capacity of infiltration and moderate adhesion, Prompt seems to possess a capacity of infiltration equal to Excite's one, but a better adhesion besides an easier modality of use.

  11. Comparative psychoacoustics: perspectives of peripheral sound analysis in mammals.

    PubMed

    Ehret, G

    1977-09-01

    Psychophysical data on hearing in mammals are summarized. The data are then correlated to the anatomy and physiology of the ear. Common mechanisms of sound transfer and analysis in the acoustic system, with stress on the auditory periphery, are discussed. In this paper an attempt is made to bring basic psychoacoustic data from man and mammals in a logical line with the anatomy, physiology, and biophysics of the ear. This comparative approach is based on man and those five mammals, including bat and dolphin, for which sufficient data are available.

  12. Arabidopsis transcription factors: genome-wide comparative analysis among eukaryotes.

    PubMed

    Riechmann, J L; Heard, J; Martin, G; Reuber, L; Jiang, C; Keddie, J; Adam, L; Pineda, O; Ratcliffe, O J; Samaha, R R; Creelman, R; Pilgrim, M; Broun, P; Zhang, J Z; Ghandehari, D; Sherman, B K; Yu, G

    2000-12-15

    The completion of the Arabidopsis thaliana genome sequence allows a comparative analysis of transcriptional regulators across the three eukaryotic kingdoms. Arabidopsis dedicates over 5% of its genome to code for more than 1500 transcription factors, about 45% of which are from families specific to plants. Arabidopsis transcription factors that belong to families common to all eukaryotes do not share significant similarity with those of the other kingdoms beyond the conserved DNA binding domains, many of which have been arranged in combinations specific to each lineage. The genome-wide comparison reveals the evolutionary generation of diversity in the regulation of transcription.

  13. The digital storytelling process: A comparative analysis from various experts

    NASA Astrophysics Data System (ADS)

    Hussain, Hashiroh; Shiratuddin, Norshuhada

    2016-08-01

    Digital Storytelling (DST) is a method of delivering information to the audience. It combines narrative and digital media content infused with the multimedia elements. In order for the educators (i.e the designers) to create a compelling digital story, there are sets of processes introduced by experts. Nevertheless, the experts suggest varieties of processes to guide them; of which some are redundant. The main aim of this study is to propose a single guide process for the creation of DST. A comparative analysis is employed where ten DST models from various experts are analysed. The process can also be implemented in other multimedia materials that used the concept of DST.

  14. Comparative study of analysis methods in biospeckle phenomenon

    NASA Astrophysics Data System (ADS)

    da Silva, Emerson Rodrigo; Muramatsu, Mikiya

    2008-04-01

    In this work we present a review of main statistical properties of speckle patterns and accomplish a comparative study of the more used methods for analysis and extraction of information from optical grainy. The first and second order space-time statistics are dicussed in an overview perspective. The biospeckle phenomenon has detailed attention, specially in its application on monitoring of activity in tissues. The main techniques used to obtain information from speckle patterns are presented, with special prominence to autocorrelation function, co-occurrence matrices, Fujii's method, Briers' contrast and spatial and temporal contrast analisys (LASCA and LASTCA). An incipient method for analysis, based on the study of sucessive correlations contrast, is introduced. Numerical simulations, using diferent probability density functions for velocities of scatterers, were made with two objectives: to test the analysis methods and to give subsidies for interpretation of in vivo results. Vegetable and animal tissues are investigated, achieving the monitoring of senescence process and vascularization maps on leaves, the accompaniment of fungi contamined fruits, the mapping of activity in flowers and the analisys of healing in rats subjected to abdominal surgery. Experiments using the biospeckle phenomenon in microscopy are carried out. At last, it is evaluated the potentiality of biospeckle as diagnosis tool in chronic vein ulcer cared with low intensity laser therapy and the better analysis methods for each kind of tissue are pointed.

  15. Comparative analysis of evaluation techniques for transport policies

    SciTech Connect

    Browne, David; Ryan, Lisa

    2011-04-15

    The objective of this paper is to examine and compare the use of a number of policy evaluation tools, which can be used to measure the impact of transport policies and programmes as part of a strategic environmental assessment (SEA) or sustainability appraisal. The evaluation tools that were examined include cost-benefit analysis (CBA), cost-effectiveness analysis (CEA) and multi-criteria decision analysis (MCDA). It was concluded that both CEA and CBA are useful for estimating the costs and/or benefits associated with transport policies but are constrained by the difficulty in quantifying non-market impacts and monetising total costs and benefits. Furthermore, CEA is limited to identifying the most 'cost-effective policy' for achieving a single, narrowly defined objective, usually greenhouse gas (GHG) reduction and is, therefore, not suitable for evaluating policy options with ancillary costs or a variety of potential benefits. Thus, CBA or CEA evaluation should be complemented by a complete environmental and socio-economic impact assessment approach such as MCDA. This method allows for participatory analysis and qualitative assessment but is subject to caveats such as subjectivity and value-laden judgments.

  16. [The information value of indices of the mathematical analysis of heart rhythm in noise exposure].

    PubMed

    Danev, S

    1988-01-01

    The effect of noise on the vegetative nervous system is well-studied. In a laboratory room simulating operator's box 6 subjects were exposed fourfold to white noise with intensity 95 dB/A. The indices of the cardiac rhythm were measured for 10 minutes, threefold, during all exposures, except the first. The measurements were before the beginning of the noise exposure, from the 5th to the 15th minute after starting and at the end (the exposure continues 135 min.). It was established that the effect of noise on the cardiac rhythm indices is most strongly expressed in the beginning. At the end of the exposure the traced indices show a tendency towards level off with the initial data. A conclusion is made that the nearly unknown, in our country, indices of the mathematical analysis of the cardiac rhythm possess high information concerning the noise hazard.

  17. Comparative analysis of human and bovine teeth: radiographic density.

    PubMed

    Tanaka, Jefferson Luis Oshiro; Medici Filho, Edmundo; Salgado, José Antônio Pereira; Salgado, Miguel Angel Castillo; Moraes, Luiz Cesar de; Moraes, Mari Eli Leonelli de; Castilho, Julio Cezar de Melo

    2008-01-01

    Since bovine teeth have been used as substitutes for human teeth in in vitro dental studies, the aim of this study was to compare the radiographic density of bovine teeth with that of human teeth to evaluate their usability for radiographic studies. Thirty bovine and twenty human teeth were cut transversally in 1 millimeter-thick slices. The slices were X-rayed using a digital radiographic system and an intraoral X-ray machine at 65 kVp and 7 mA. The exposure time (0.08 s) and the target-sensor distance (40 cm) were standardized for all the radiographs. The radiographic densities of the enamel, coronal dentin and radicular dentin of each slice were obtained separately using the 'histogram' tool of Adobe Photoshop 7.0 software. The mean radiographic densities of the enamel, coronal dentin and radicular dentin were calculated by the arithmetic mean of the slices of each tooth. One-way ANOVA demonstrated statistically significant differences for the densities of bovine and human enamel (p < 0.05) and for bovine and human coronal dentin (p < 0.05). No statistically significant differences were found for the bovine and human radicular dentin (p > 0.05). Based on the results, the authors concluded that: a) the radiographic density of bovine enamel is significantly higher than that of human enamel; b) the radiodensity of bovine coronal dentin is statistically lower than the radiodensity of human coronal dentin; bovine radicular dentin is also less radiodense than human radicular dentin, although this difference was not statistically significant; c) bovine teeth should be used with care in radiographic in vitro studies.

  18. Mediation analysis allowing for exposure-mediator interactions and causal interpretation: theoretical assumptions and implementation with SAS and SPSS macros

    PubMed Central

    Valeri, Linda; VanderWeele, Tyler J.

    2012-01-01

    Mediation analysis is a useful and widely employed approach to studies in the field of psychology and in the social and biomedical sciences. The contributions of this paper are several-fold. First we seek to bring the developments in mediation analysis for non linear models within the counterfactual framework to the psychology audience in an accessible format and compare the sorts of inferences about mediation that are possible in the presence of exposure-mediator interaction when using a counterfactual versus the standard statistical approach. Second, the work by VanderWeele and Vansteelandt (2009, 2010) is extended here to allow for dichotomous mediators and count outcomes. Third, we provide SAS and SPSS macros to implement all of these mediation analysis techniques automatically and we compare the types of inferences about mediation that are allowed by a variety of software macros. PMID:23379553

  19. Comparative risk assessment of tobacco smoke constituents using the margin of exposure approach: the neglected contribution of nicotine

    PubMed Central

    Baumung, Claudia; Rehm, Jürgen; Franke, Heike; Lachenmeier, Dirk W.

    2016-01-01

    Nicotine was not included in previous efforts to identify the most important toxicants of tobacco smoke. A health risk assessment of nicotine for smokers of cigarettes was conducted using the margin of exposure (MOE) approach and results were compared to literature MOEs of various other tobacco toxicants. The MOE is defined as ratio between toxicological threshold (benchmark dose) and estimated human intake. Dose-response modelling of human and animal data was used to derive the benchmark dose. The MOE was calculated using probabilistic Monte Carlo simulations for daily cigarette smokers. Benchmark dose values ranged from 0.004 mg/kg bodyweight for symptoms of intoxication in children to 3 mg/kg bodyweight for mortality in animals; MOEs ranged from below 1 up to 7.6 indicating a considerable consumer risk. The dimension of the MOEs is similar to those of other tobacco toxicants with high concerns relating to adverse health effects such as acrolein or formaldehyde. Owing to the lack of toxicological data in particular relating to cancer, long term animal testing studies for nicotine are urgently necessary. There is immediate need of action concerning the risk of nicotine also with regard to electronic cigarettes and smokeless tobacco. PMID:27759090

  20. Comparative Long-Term Toxicity of Libby Amphibole and Amosite Asbestos after Single or Multiple Intratracheal Exposures

    EPA Science Inventory

    In former mine workers of Libby, Montana, exposure to amphibole-containing vermiculite has been linked to increased rates of asbestosis, lung cancer, and mesothelioma. Although many studies have shown adverse effects of Libby Amphibole (LA) exposure, little is known regarding th...

  1. Cytotoxicity of carbon nanotube variants: a comparative in vitro exposure study with A549 epithelial and J774 macrophage cells.

    PubMed

    Kumarathasan, Prem; Breznan, Dalibor; Das, Dharani; Salam, Mohamed A; Siddiqui, Yunus; MacKinnon-Roy, Christine; Guan, Jingwen; de Silva, Nimal; Simard, Benoit; Vincent, Renaud

    2015-03-01

    While production of engineered carbon nanotubes (CNTs) has escalated in recent years, knowledge of risk associated with exposure to these materials remains unclear. We report on the cytotoxicity of four CNT variants in human lung epithelial cells (A549) and murine macrophages (J774). Morphology, metal content, aggregation/agglomeration state, pore volume, surface area and modifications were determined for the pristine and oxidized single-walled (SW) and multi-walled (MW) CNTs. Cytotoxicity was evaluated by cellular ATP content, BrdU incorporation, lactate dehydrogenase (LDH) release, and CellTiter-Blue (CTB) reduction assays. All CNTs were more cytotoxic than respirable TiO2 and SiO2 reference particles. Oxidation of CNTs removed most metallic impurities but introduced surface polar functionalities. Although slopes of fold changes for cytotoxicity endpoints were steeper with J774 compared to A549 cells, CNT cytotoxicity ranking in both cell types was assay-dependent. Based on CTB reduction and BrdU incorporation, the cytotoxicity of the polar oxidized CNTs was higher compared to the pristine CNTs. In contrast, pristine CNTs were more cytotoxic than oxidized CNTs when assessed for cellular ATP and LDH. Correlation analyses between CNTs' physico-chemical properties and average relative potency revealed the impact of metal content and surface area on the potency values estimated using ATP and LDH assays, while surface polarity affected the potency values estimated from CTB and BrdU assays. We show that in order to reliably estimate the risk posed by these materials, in vitro toxicity assessment of CNTs should be conducted with well characterized materials, in multiple cellular models using several cytotoxicity assays that report on distinct cellular processes.

  2. Effects of exposure measurement error in the analysis of health effects from traffic-related air pollution.

    PubMed

    Baxter, Lisa K; Wright, Rosalind J; Paciorek, Christopher J; Laden, Francine; Suh, Helen H; Levy, Jonathan I

    2010-01-01

    In large epidemiological studies, many researchers use surrogates of air pollution exposure such as geographic information system (GIS)-based characterizations of traffic or simple housing characteristics. It is important to evaluate quantitatively these surrogates against measured pollutant concentrations to determine how their use affects the interpretation of epidemiological study results. In this study, we quantified the implications of using exposure models derived from validation studies, and other alternative surrogate models with varying amounts of measurement error on epidemiological study findings. We compared previously developed multiple regression models characterizing residential indoor nitrogen dioxide (NO(2)), fine particulate matter (PM(2.5)), and elemental carbon (EC) concentrations to models with less explanatory power that may be applied in the absence of validation studies. We constructed a hypothetical epidemiological study, under a range of odds ratios, and determined the bias and uncertainty caused by the use of various exposure models predicting residential indoor exposure levels. Our simulations illustrated that exposure models with fairly modest R(2) (0.3 to 0.4 for the previously developed multiple regression models for PM(2.5) and NO(2)) yielded substantial improvements in epidemiological study performance, relative to the application of regression models created in the absence of validation studies or poorer-performing validation study models (e.g., EC). In many studies, models based on validation data may not be possible, so it may be necessary to use a surrogate model with more measurement error. This analysis provides a technique to quantify the implications of applying various exposure models with different degrees of measurement error in epidemiological research.

  3. Comparative Analysis of Gene Content Evolution in Phytoplasmas and Mycoplasmas

    PubMed Central

    Lin, Chan-Pin; Kuo, Chih-Horng

    2012-01-01

    Phytoplasmas and mycoplasmas are two groups of important pathogens in the bacterial class Mollicutes. Because of their economical and clinical importance, these obligate pathogens have attracted much research attention. However, difficulties involved in the empirical study of these bacteria, particularly the fact that phytoplasmas have not yet been successfully cultivated outside of their hosts despite decades of attempts, have greatly hampered research progress. With the rapid advancements in genome sequencing, comparative genome analysis provides a new approach to facilitate our understanding of these bacteria. In this study, our main focus is to investigate the evolution of gene content in phytoplasmas, mycoplasmas, and their common ancestor. By using a phylogenetic framework for comparative analysis of 12 complete genome sequences, we characterized the putative gains and losses of genes in these obligate parasites. Our results demonstrated that the degradation of metabolic capacities in these bacteria has occurred predominantly in the common ancestor of Mollicutes, prior to the evolutionary split of phytoplasmas and mycoplasmas. Furthermore, we identified a list of genes that are acquired by the common ancestor of phytoplasmas and are conserved across all strains with complete genome sequences available. These genes include several putative effectors for the interactions with hosts and may be good candidates for future functional characterization. PMID:22479625

  4. Profile analysis of after-effects experienced during exposure to several virtual reality environments

    NASA Technical Reports Server (NTRS)

    Kennedy, Robert S.; Jones, Marshall B.; Lilienthal, Michael G.; Harm, Deborah L.

    1994-01-01

    Motion sickness symptoms are an unwanted by-product of exposure to virtual environments. This problem is not new and was reported in the early flight simulators and experiments on ego motions and vection. The cardinal symptom of motion sickness is, of course, vomiting, but this symptom is ordinarily preceded by a variety of other symptoms. In his classic studies of motion sickness conducted before and during World War II, G. R. Wendt introduced a three point scale to score motion sickness beyond a vomit/no vomit dichotomy. Later, Navy scientists developed a Motion Sickness Questionnaire (MSQ), originally for use in a slowly rotating room. In the last 20 years the MSQ has been used in a series of studies of air, sea, and space sickness. Only recently, however, has it been appreciated that symptom patterns in the MSQ are not uniform but vary with the way sickness is induced. In seasickness, for example, nausea is the most prominent symptom. In Navy simulators, however, the most common symptom is eye strain, especially when cathode ray tubes are employed in the simulation. The latter result was obtained in a survey of over 1,500 pilot exposures. Using this database, Essex scientists conducted a factor analysis of the MSQ. We found that signs and symptoms of motion sickness fell mainly into three clusters: 1) oculomotor disturbance, 2) nausea and related neurovegetative problems, and 3) disorientation, ataxia, and vertigo. We have since rescored the MSQ results obtained in Navy simulators in terms of these three components. We have also compared these and other profiles obtained from three different vitual reality systems to profiles obtained in sea sickness, space sickness, and alcohol intoxication. We will show examples of these various profiles and point out simularities and differences among them which indicate aspects of what might be called 'virtual-reality sickness'.

  5. Pesticide exposure and risk of bladder cancer: A meta-analysis

    PubMed Central

    Xie, Bo; Zhu, Yi; Wu, Jian; Li, Shiqi; Meng, Shuai; Zheng, Xiangyi; Ji, Alin; Xie, Liping

    2016-01-01

    Objective We conducted a meta-analysis to quantitatively evaluate the correlation between pesticide exposure and the risk of bladder cancer by summarizing the results of published case-control and cohort studies. Methods A systematic literature search of articles update to February 2015 was conducted via Pubmed, Web of Science, Cochrane Library, and the Chinese National Knowledge Infrastructure (CNKI) databases, and the references of the retrieved articles. Fixed- or random-effect models were used to summarize the estimates of OR with 95% CIs for the highest versus the lowest exposure of pesticide. Results The pooled OR estimates indicated that pesticide exposure was associated with an increased risk of bladder cancer (OR=1.649, 95% CI 1.223-2.223). In subgroup analysis, we detected pesticide exposure demonstrated as a significant risk factor on bladder cancer in America (OR=1.741, 95% CI 1.270-2.388). Similar results were discovered in both case-control group and cohort group (OR=2.075, 95% CI 1.183-3.638, OR=1.146, 95% CI 1.074-1.223, respectively). No evidence of publication bias was found by Begg's or Egger's test (P = 0.210, P = 0.358, respectively). Conclusion In conclusion, our meta-analysis indicated that pesticide exposure was associated with an increased risk of bladder cancer. Further researches should be conducted to confirm the findings in our study and better clarify the potential biological mechanisms. PMID:27557494

  6. The Comparative Analysis of Aversive and Ordinary Noise.

    NASA Astrophysics Data System (ADS)

    Mobley, C. Marion, Jr.

    There is a vast amount of literature concerning the psychological and physiological effects of ordinary noise on the individual. However, few publications have addressed the analysis of aversive noise. This research analyzes three noises which produce the familiar goose flesh or chilling effect responsivity. These aversive sounds which are made by chalk squeaking on the chalkboard, fingernails on the chalkboard and rubbing styrofoam against a smooth surface are digitally compared to ordinary noise to show how these aversive sounds differ from sounds which are only annoying. This work, which uses Fast Fourier Transform (FFT) analysis is a combination with cross correlation analysis and other innovative methods to produce comparative data on noises, illustrates subtle differences between ordinary and aversive noise which may be useful for future work in acoustics or experimental psychology. The literature review shows disagreement among the numerous works on the effects of ordinary noise on human subjects. One explanation for this difference is the failure to adequately measure and define the dynamic nature of the noise used. The existing literature also establishes that a mixture of tones plus random noise is more annoying (but not aversive) than either the random noise or the tones alone. This investigation shows that one property of aversive noises is the combination of randomness plus tones which vary rapidly with time. This paper utilizes a new digital technique which improves the FFT analyzer resolution by a factor of 25. The resulting +/-2 Hz accuracy facilitated the presentation of frequency variation as a function of time data. Other computer generated graphical data includes the percent harmonic deviation as a function of time, the rate of change of fundamental frequency, and the rate of change in harmonic deviation. From these dynamic data, average values are calculated which show the aversive noise to be consistently greater in mean frequency deviation

  7. Light exposure at night, sleep duration, melatonin, and breast cancer: a dose-response analysis of observational studies.

    PubMed

    Yang, Wan-Shui; Deng, Qin; Fan, Wen-Yan; Wang, Wei-Ye; Wang, Xin

    2014-07-01

    Evidence from observational studies on light at night (LAN) exposure, sleep duration, endogenous melatonin levels, and risk for breast cancer in women is conflicting. This led us to conduct a dose-response analysis of published observational data. Pertinent studies were identified by searching Medline, Web of Science, and EMBASE through April 2013. The dose-response relationship between sleep duration, urinary 6-sulphatoxymelatonin levels, and breast cancer was assessed using the restricted cubic spline model and by multivariate random-effects metaregression. A separate meta-analysis was also carried out to calculate the relative risks (RRs) with 95% confidence intervals (CIs) for breast cancer for the comparable categories or highest levels of exposure versus the lowest levels. Twelve case-control and four cohort studies were included in the analysis. High artificial LAN exposure is associated with an increased risk for breast cancer (RR=1.17, 95% CI: 1.11-1.23), but not ambient LAN exposure (RR=0.91, 95% CI: 0.78-1.07). The summary RR for breast cancer is 1.00 (95% CI: 0.995-1.01) for an increment of 1 h of sleep per night. No significant dose-response relationship between sleep duration and breast cancer was found either for the linearity test (Ptrend=0.725) or for the nonlinearity (Ptrend=0.091) test. An increasein of 15 ng/mg creatinine in urinary 6-sulphatoxymelatonin is associated with a 14% reduced risk for breast cancer (RR=0.86, 95% CI: 0.78-0.95), with a linear dose-response trend (Ptrend=0.003). There was no evidence of substantial heterogeneity or publication bias in the analysis. Our study adds to the evidence of LAN breast cancer theory. Further research in this area is warranted.

  8. A comparison of infant hair, cord blood and meconium analysis to detect fetal exposure to environmental pesticides

    PubMed Central

    Ostrea, Enrique M.; Bielawski, Dawn M.; Posecion, Norberto C.; Corrion, Melissa; Villanueva-Uy, Esterlita; Jin, Yan; Janisse, James J.; Ager, Joel W.

    2008-01-01

    OBJECTIVE The detection of fetal exposure to environmental pesticides is important because many of the pesticides are neurotoxicants and fetal exposure to these compounds can adversely affect prenatal and subsequent neurodevelopment. The aim of this study was to determine, by the comparative analysis of infant hair, cord blood and meconium, the most sensitive matrix to detect fetal exposure to pesticides. PATIENTS AND METHODS Pregnant women were prospectively recruited from an agricultural site in the Philippines where a preliminary survey indicated a substantial use at home and in the farm of the following pesticides: propoxur, cyfluthrin, chlorpyrifos, cypermethrin, pretilachlor, bioallethrin, malathion, diazinon and transfluthrin. Infant hair, cord blood and meconium were obtained after birth and were analyzed by gas chromatography/mass spectrometry for the above compounds, including lindane and DDT (1,1,1-trichloro-2,2-bis, p-chlorophenylethane) and some of their known metabolites. RESULTS A total of 638 infants were included in the study. The highest exposure rate to pesticides was detected in meconium (23.8% to propoxur, 1.9% to pretilachlor, 1.9% to cypermethrin, 0.8% to cyfluthrin, 0.6% to DDT and 0.3% to malathion and bioallethrin). Cord blood was only positive for propoxur (1.9%) whereas infant hair was only positive for chlorpyrifos (0.2%). The highest exposure was to household pesticide (propoxur). The frequency and concentration of pesticides were compared in the three matrices and there was a significantly higher frequency and concentration of propoxur, pretilachlor, DDT, cyfluthrin and cypermethrin in meconium compared to cord blood and infant hair. Pesticide metabolites were not found in any of the matrices analyzed, except in one meconium sample which was positive for DDE (4,4′ dichlorodiphenyldichloro ethylene), a DDT metabolite. CONCLUSIONS There is significant exposure of the pregnant woman and her fetus to pesticides, particularly to the home

  9. Patient-specific finite element analysis of chronic contact stress exposure after intraarticular fracture of the tibial plafond.

    PubMed

    Li, Wendy; Anderson, Donald D; Goldsworthy, Jane K; Marsh, J Lawrence; Brown, Thomas D

    2008-08-01

    The role of altered contact mechanics in the pathogenesis of posttraumatic osteoarthritis (PTOA) following intraarticular fracture remains poorly understood. One proposed etiology is that residual incongruities lead to altered joint contact stresses that, over time, predispose to PTOA. Prevailing joint contact stresses following surgical fracture reduction were quantified in this study using patient-specific contact finite element (FE) analysis. FE models were created for 11 ankle pairs from tibial plafond fracture patients. Both (reduced) fractured ankles and their intact contralaterals were modeled. A sequence of 13 loading instances was used to simulate the stance phase of gait. Contact stresses were summed across loadings in the simulation, weighted by resident time in the gait cycle. This chronic exposure measure, a metric of degeneration propensity, was then compared between intact and fractured ankle pairs. Intact ankles had lower peak contact stress exposures that were more uniform and centrally located. The series-average peak contact stress elevation for fractured ankles was 38% (p = 0.0015; peak elevation was 82%). Fractured ankles had less area with low contact stress exposure than intact ankles and a greater area with high exposure. Chronic contact stress overexposures (stresses exceeding a damage threshold) ranged from near zero to a high of 18 times the matched intact value. The patient-specific FE models represent substantial progress toward elucidating the relationship between altered contact stresses and the outcome of patients treated for intraarticular fractures.

  10. Toxicity and transcriptomic analysis in Hyalella azteca suggests increased exposure and susceptibility of epibenthic organisms to zinc oxide nanoparticles.

    PubMed

    Poynton, Helen C; Lazorchak, James M; Impellitteri, Christopher A; Blalock, Bonnie; Smith, Mark E; Struewing, Katherine; Unrine, Jason; Roose, Deborah

    2013-08-20

    Nanoparticles (NPs) are expected to make their way into the aquatic environment where sedimentation of particles will likely occur, putting benthic organisms at particular risk. Therefore, organisms such as Hyalella azteca, an epibenthic crustacean which forages at the sediment surface, is likely to have a high potential exposure. Here we show that zinc oxide (ZnO) NPs are more toxic to H. azteca compared with the corresponding metal ion, Zn(2+). Dissolution of ZnO NPs contributes about 50% of the Zn measured in the ZnO NP suspensions, and cannot account for the toxicity of these particles to H. azteca. However, gene expression analysis is unable to distinguish between the ZnO NP exposures and zinc sulfate (ZnSO4) exposures at equitoxic concentrations. These results lead us to hypothesize that ZnO NPs provide an enhanced exposure route for Zn(2+) uptake into H. azteca, and possibly other sediment dwelling organisms. Our study supports the prediction that sediment dwelling organisms are highly susceptible to the effects of ZnO NPs and should be considered in the risk assessment of these nanomaterials.

  11. Extreme storm surges: a comparative study of frequency analysis approaches

    NASA Astrophysics Data System (ADS)

    Hamdi, Y.; Bardet, L.; Duluc, C.-M.; Rebour, V.

    2014-08-01

    In France, nuclear facilities were designed around very low probabilities of failure. Nevertheless, some extreme climatic events have given rise to exceptional observed surges (outliers) much larger than other observations, and have clearly illustrated the potential to underestimate the extreme water levels calculated with the current statistical methods. The objective of the present work is to conduct a comparative study of three approaches to extreme value analysis, including the annual maxima (AM), the peaks-over-threshold (POT) and the r-largest order statistics (r-LOS). These methods are illustrated in a real analysis case study. All data sets were screened for outliers. Non-parametric tests for randomness, homogeneity and stationarity of time series were used. The shape and scale parameter stability plots, the mean excess residual life plot and the stability of the standard errors of return levels were used to select optimal thresholds and r values for the POT and r-LOS method, respectively. The comparison of methods was based on (i) the uncertainty degrees, (ii) the adequacy criteria and tests, and (iii) the visual inspection. It was found that the r-LOS and POT methods have reduced the uncertainty on the distribution parameters and return level estimates and have systematically shown values of the 100 and 500-year return levels smaller than those estimated with the AM method. Results have also shown that none of the compared methods has allowed a good fit at the right tail of the distribution in the presence of outliers. As a perspective, the use of historical information was proposed in order to increase the representativeness of outliers in data sets. Findings are of practical relevance, not only to nuclear energy operators in France, for applications in storm surge hazard analysis and flood management, but also for the optimal planning and design of facilities to withstand extreme environmental conditions, with an appropriate level of risk.

  12. Texture analysis of multiple sclerosis: a comparative study.

    PubMed

    Zhang, Jing; Tong, Longzheng; Wang, Lei; Li, Ning

    2008-10-01

    The difficulty of using magnetic resonance imaging (MRI) to support early diagnosis of multiple sclerosis (MS) stems from the subtle pathological changes in the central nervous system (CNS). In this study, texture analysis was performed on MR images of MS patients and normal controls and a combined set of texture features were explored in order to better discriminate tissues between MS lesions, normal appearing white matter (NAWM) and normal white matter (NWM). Features were extracted from gradient matrix, run-length (RL) matrix, gray level co-occurrence matrix (GLCM), autoregressive (AR) model and wavelet analysis, and were selected based on greatest difference between different tissue types. The results of the combined set of texture features were compared with our previous results of GLCM-based features alone. The results of this study demonstrated that (1) with the combined set of texture features, classification was perfect (100%) between MS lesions and NAWM (or NWM), less successful (88.89%) among the three tissue types and worst (58.33%) between NAWM and NWM; (2) compared with GLCM-based features, the combined set of texture features were better at discriminating MS lesions and NWM, equally good at discriminating MS lesions and NAWM and at all three tissue types, but less effective in classification between NAWM and NWM. This study suggested that texture analysis with the combined set of texture features may be equally good or more advantageous than the commonly used GLCM-based features alone in discriminating MS lesions and NWM/NAWM and in supporting early diagnosis of MS.

  13. Comparative Analysis of Vertebrate Diurnal/Circadian Transcriptomes

    PubMed Central

    Boyle, Greg; Richter, Kerstin; Priest, Henry D.; Traver, David; Mockler, Todd C.; Chang, Jeffrey T.; Kay, Steve A.

    2017-01-01

    From photosynthetic bacteria to mammals, the circadian clock evolved to track diurnal rhythms and enable organisms to anticipate daily recurring changes such as temperature and light. It orchestrates a broad spectrum of physiology such as the sleep/wake and eating/fasting cycles. While we have made tremendous advances in our understanding of the molecular details of the circadian clock mechanism and how it is synchronized with the environment, we still have rudimentary knowledge regarding its connection to help regulate diurnal physiology. One potential reason is the sheer size of the output network. Diurnal/circadian transcriptomic studies are reporting that around 10% of the expressed genome is rhythmically controlled. Zebrafish is an important model system for the study of the core circadian mechanism in vertebrate. As Zebrafish share more than 70% of its genes with human, it could also be an additional model in addition to rodent for exploring the diurnal/circadian output with potential for translational relevance. Here we performed comparative diurnal/circadian transcriptome analysis with established mouse liver and other tissue datasets. First, by combining liver tissue sampling in a 48h time series, transcription profiling using oligonucleotide arrays and bioinformatics analysis, we profiled rhythmic transcripts and identified 2609 rhythmic genes. The comparative analysis revealed interesting features of the output network regarding number of rhythmic genes, proportion of tissue specific genes and the extent of transcription factor family expression. Undoubtedly, the Zebrafish model system will help identify new vertebrate outputs and their regulators and provides leads for further characterization of the diurnal cis-regulatory network. PMID:28076377

  14. Comparative analysis of solid waste management in 20 cities.

    PubMed

    Wilson, David C; Rodic, Ljiljana; Scheinberg, Anne; Velis, Costas A; Alabaster, Graham

    2012-03-01

    This paper uses the 'lens' of integrated and sustainable waste management (ISWM) to analyse the new data set compiled on 20 cities in six continents for the UN-Habitat flagship publication Solid Waste Management in the World's Cities. The comparative analysis looks first at waste generation rates and waste composition data. A process flow diagram is prepared for each city, as a powerful tool for representing the solid waste system as a whole in a comprehensive but concise way. Benchmark indicators are presented and compared for the three key physical components/drivers: public health and collection; environment and disposal; and resource recovery--and for three governance strategies required to deliver a well-functioning ISWM system: inclusivity; financial sustainability; and sound institutions and pro-active policies. Key insights include the variety and diversity of successful models - there is no 'one size fits all'; the necessity of good, reliable data; the importance of focusing on governance as well as technology; and the need to build on the existing strengths of the city. An example of the latter is the critical role of the informal sector in the cities in many developing countries: it not only delivers recycling rates that are comparable with modern Western systems, but also saves the city authorities millions of dollars in avoided waste collection and disposal costs. This provides the opportunity for win-win solutions, so long as the related wider challenges can be addressed.

  15. Multivariate Comparative Analysis of Stock Exchanges: The European Perspective

    NASA Astrophysics Data System (ADS)

    Koralun-Bereźnicka, Julia

    The aim of the research is to perform a multivariate comparative analysis of 20 European stock exchanges in order to identify the main similarities between the objects. Due to the convergence process of capital markets in Europe the similarities between stock exchanges could be expected to increase over time. The research is meant to show whether and how these similarities change. Consequently, the distances between clusters of similar stock exchanges should become less significant, which the analysis also aims at verifying. The basis of comparison is a set of 48 monthly variables from the period January, 2003 to December, 2006. The variables are classified into three categories: size of the market, equity trading and bonds. The paper aims at identifying the clusters of alike stock exchanges and at finding the characteristic features of each of the distinguished groups. The obtained categorization to some extent corresponds with the division of the European Union into “new” and “old” member countries. Clustering method, performed for each quarter separately, also reveals that the classification is fairly stable in time. The factor analysis, which was carried out to reduce the number of variables, reveals three major factors behind the data, which are related with the earlier mentioned categories of variables.

  16. White matter degeneration in schizophrenia: a comparative diffusion tensor analysis

    NASA Astrophysics Data System (ADS)

    Ingalhalikar, Madhura A.; Andreasen, Nancy C.; Kim, Jinsuh; Alexander, Andrew L.; Magnotta, Vincent A.

    2010-03-01

    Schizophrenia is a serious and disabling mental disorder. Diffusion tensor imaging (DTI) studies performed on schizophrenia have demonstrated white matter degeneration either due to loss of myelination or deterioration of fiber tracts although the areas where the changes occur are variable across studies. Most of the population based studies analyze the changes in schizophrenia using scalar indices computed from the diffusion tensor such as fractional anisotropy (FA) and relative anisotropy (RA). The scalar measures may not capture the complete information from the diffusion tensor. In this paper we have applied the RADTI method on a group of 9 controls and 9 patients with schizophrenia. The RADTI method converts the tensors to log-Euclidean space where a linear regression model is applied and hypothesis testing is performed between the control and patient groups. Results show that there is a significant difference in the anisotropy between patients and controls especially in the parts of forceps minor, superior corona radiata, anterior limb of internal capsule and genu of corpus callosum. To check if the tensor analysis gives a better idea of the changes in anisotropy, we compared the results with voxelwise FA analysis as well as voxelwise geodesic anisotropy (GA) analysis.

  17. Myelodysplastic Syndrome and Benzene Exposure Among Petroleum Workers: An International Pooled Analysis

    PubMed Central

    2012-01-01

    Background Benzene at high concentrations is known to cause acute myeloid leukemia (AML), but its relationship with other lymphohematopoietic (LH) cancers remains uncertain, particularly at low concentrations. In this pooled analysis, we examined the risk of five LH cancers relative to lower levels of benzene exposure in petroleum workers. Methods We updated three nested case–control studies from Australia, Canada, and the United Kingdom with new incident LH cancers among petroleum distribution workers through December 31, 2006, and pooled 370 potential case subjects and 1587 matched LH cancer-free control subjects. Quantitative benzene exposure in parts per million (ppm) was blindly reconstructed using historical monitoring data, and exposure certainty was scored as high, medium, or low. Two hematopathologists assigned diagnoses and scored the certainty of diagnosis as high, medium, or low. Dose–response relationships were examined for five LH cancers, including the three most common leukemia cell-types (AML, chronic myeloid leukemia [CML], and chronic lymphoid leukemia [CLL]) and two myeloid tumors (myelodysplastic syndrome [MDS] and myeloproliferative disease [MPD]). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression, controlling for age, sex, and time period. Results Cumulative benzene exposure showed a monotonic dose–response relationship with MDS (highest vs lowest tertile, >2.93 vs ≤0.348 ppm-years, OR = 4.33, 95% CI = 1.31 to 14.3). For peak benezene exposures (>3 ppm), the risk of MDS was increased in high and medium certainty diagnoses (peak exposure vs no peak exposure, OR = 6.32, 95% CI = 1.32 to 30.2) and in workers having the highest exposure certainty (peak exposure vs no peak exposure, OR = 5.74, 95% CI = 1.05 to 31.2). There was little evidence of dose–response relationships for AML, CLL, CML, or MPD. Conclusions Relatively low-level exposure to benzene experienced by petroleum

  18. Comparative transcriptomics reveals genes involved in metabolic and immune pathways in the digestive gland of scallop Chlamys farreri following cadmium exposure

    NASA Astrophysics Data System (ADS)

    Zhang, Hui; Zhai, Yuxiu; Yao, Lin; Jiang, Yanhua; Li, Fengling

    2016-05-01

    Chlamys farreri is an economically important mollusk that can accumulate excessive amounts of cadmium (Cd). Studying the molecular mechanism of Cd accumulation in bivalves is difficult because of the lack of genome background. Transcriptomic analysis based on high-throughput RNA sequencing has been shown to be an efficient and powerful method for the discovery of relevant genes in non-model and genome reference-free organisms. Here, we constructed two cDNA libraries (control and Cd exposure groups) from the digestive gland of C. farreri and compared the transcriptomic data between them. A total of 227 673 transcripts were assembled into 105 071 unigenes, most of which shared high similarity with sequences in the NCBI non-redundant protein database. For functional classification, 24 493 unigenes were assigned to Gene Ontology terms. Additionally, EuKaryotic Ortholog Groups and Kyoto Encyclopedia of Genes and Genomes analyses assigned 12 028 unigenes to 26 categories and 7 849 unigenes to five pathways, respectively. Comparative transcriptomics analysis identified 3 800 unigenes that were differentially expressed in the Cd-treated group compared with the control group. Among them, genes associated with heavy metal accumulation were screened, including metallothionein, divalent metal transporter, and metal tolerance protein. The functional genes and predicted pathways identified in our study will contribute to a better understanding of the metabolic and immune system in the digestive gland of C. farreri. In addition, the transcriptomic data will provide a comprehensive resource that may contribute to the understanding of molecular mechanisms that respond to marine pollutants in bivalves.

  19. Global transcriptional analysis of Mycoplasma hyopneumoniae following exposure to norepinephrine.

    PubMed

    Oneal, Michael J; Schafer, Erin R; Madsen, Melissa L; Minion, F Chris

    2008-09-01

    Mycoplasma hyopneumoniae, a component of the porcine respiratory disease complex, colonizes the respiratory tract of swine by binding to the cilia of the bronchial epithelial cells. Mechanisms of pathogenesis are poorly understood for M. hyopneumoniae, but previous work has indicated that it responds to the environmental stressors heat shock, iron deprivation and oxidative compounds. For successful infection, M. hyopneumoniae must effectively resist host responses to the colonization of the respiratory tract. Among these are changes in hormonal levels in the mucosal secretions. Recent work in the stress responses of other bacteria has included the response to the catecholamine norepinephrine. The idea that M. hyopneumoniae can respond to a host hormone, however, is novel and has not previously been demonstrated. To test this, organisms in the early exponential phase of growth were exposed to 100 muM norepinephrine for 4 h, and RNA samples from these cultures were collected and compared to RNA samples from control cultures using two-colour PCR-based M. hyopneumoniae microarrays. The M. hyopneumoniae response included slowed growth and changes in mRNA transcript levels of 84 genes, 53 of which were upregulated in response to norepinephrine. A larger proportion of the genes upregulated than those downregulated were involved with transcription and translation. The downregulated genes were mostly involved with metabolism, which correlated with the reduction in growth of the mycoplasma. Approximately 51 % of the genes were hypothetical with no known function. Thus, in response to norepinephrine, M. hyopneumoniae appears to upregulate protein expression while downregulating general metabolism.

  20. Underground Corrosion of Activated Metals, 6-Year Exposure Analysis

    SciTech Connect

    M. K. Adler Flitton; T. S. Yoder

    2006-03-01

    The subsurface radioactive disposal site located at the Idaho National Laboratory contains neutronactivated metals from non-fuel nuclear-reactor-core components. A long-term underground corrosion test is being conducted to obtain site-specific corrosion rates to support efforts to more accurately estimate the transfer of activated elements in the surrounding arid vadose zone environment. The test uses nonradioactive metal coupons representing the prominent neutron-activated materials buried at the disposal location, namely, Type 304L stainless steel (UNS S30403), Type 316L stainless steel (S31603), nickel-chromium alloy (UNS NO7718), beryllium, aluminum 6061-T6 (A96061), and a zirconium alloy (UNS R60804). In addition, carbon steel (the material presently used in the cask disposal liners and other disposal containers) and a duplex stainless steel (UNS S32550) are also included in the test. This paper briefly describes the ongoing test and presents the results of corrosion analysis from coupons exposed underground for 1, 3, and 6 years.

  1. Occupational exposure to mineral fibres: analysis of results stored on colchic database.

    PubMed

    Kauffer, Edmond; Vincent, Raymond

    2007-03-01

    The aim of this paper is to present fibre exposure data recorded on the COLCHIC database. This database consolidates all occupational exposure data collected in French companies by the Caisses Régionales d'Assurance Maladie (regional health insurance funds, CRAM) and the Institut National de Recherche et de Sécurité (national institute for research and safety, INRS). A total of 8029 concentration results, expressed in number of fibres measured by phase-contrast optical microscopy, are available for exposure to asbestos fibres, ceramic fibres and man-made mineral fibres other than ceramic fibres. Presentation of base data by activity branch, activity sector or workplace permits identification of situations, for which prevention efforts are most essential. Analysis of exposure levels during the 1986-2004 period show that these are broadly influenced by changes in the exposure limit values. Wearing of respiratory protection equipment by employees is also discussed. The data may be helpful to occupational physicians performing occupational screening of exposed workers and to epidemiologists seeking information for building job-exposures matrices. In this respect, a database (FIBREX) will be available on the INRS web site (www.inrs.fr) at the beginning of 2007. This database will provide a higher level of detail in activity and workplace description than that which was possible for practical reasons in this paper.

  2. Industrial Acetogenic Biocatalysts: A Comparative Metabolic and Genomic Analysis

    PubMed Central

    Bengelsdorf, Frank R.; Poehlein, Anja; Linder, Sonja; Erz, Catarina; Hummel, Tim; Hoffmeister, Sabrina; Daniel, Rolf; Dürre, Peter

    2016-01-01

    Synthesis gas (syngas) fermentation by anaerobic acetogenic bacteria employing the Wood–Ljungdahl pathway is a bioprocess for production of biofuels and biocommodities. The major fermentation products of the most relevant biocatalytic strains (Clostridium ljungdahlii, C. autoethanogenum, C. ragsdalei, and C. coskatii) are acetic acid and ethanol. A comparative metabolic and genomic analysis using the mentioned biocatalysts might offer targets for metabolic engineering and thus improve the production of compounds apart from ethanol. Autotrophic growth and product formation of the four wild type (WT) strains were compared in uncontrolled batch experiments. The genomes of C. ragsdalei and C. coskatii were sequenced and the genome sequences of all four biocatalytic strains analyzed in comparative manner. Growth and product spectra (acetate, ethanol, 2,3-butanediol) of C. autoethanogenum, C. ljungdahlii, and C. ragsdalei were rather similar. In contrast, C. coskatii produced significantly less ethanol and its genome sequence lacks two genes encoding aldehyde:ferredoxin oxidoreductases (AOR). Comparative genome sequence analysis of the four WT strains revealed high average nucleotide identity (ANI) of C. ljungdahlii and C. autoethanogenum (99.3%) and C. coskatii (98.3%). In contrast, C. ljungdahlii WT and C. ragsdalei WT showed an ANI-based similarity of only 95.8%. Additionally, recombinant C. ljungdahlii strains were constructed that harbor an artificial acetone synthesis operon (ASO) consisting of the following genes: adc, ctfA, ctfB, and thlA (encoding acetoacetate decarboxylase, acetoacetyl-CoA:acetate/butyrate:CoA-transferase subunits A and B, and thiolase) under the control of thlA promoter (PthlA) from C. acetobutylicum or native pta-ack promoter (Ppta-ack) from C. ljungdahlii. Respective recombinant strains produced 2-propanol rather than acetone, due to the presence of a NADPH-dependent primary-secondary alcohol dehydrogenase that converts acetone to 2

  3. Comprehensive comparative analysis of kinesins in photosynthetic eukaryotes

    PubMed Central

    Richardson, Dale N; Simmons, Mark P; Reddy, Anireddy SN

    2006-01-01

    Background Kinesins, a superfamily of molecular motors, use microtubules as tracks and transport diverse cellular cargoes. All kinesins contain a highly conserved ~350 amino acid motor domain. Previous analysis of the completed genome sequence of one flowering plant (Arabidopsis) has resulted in identification of 61 kinesins. The recent completion of genome sequencing of several photosynthetic and non-photosynthetic eukaryotes that belong to divergent lineages offers a unique opportunity to conduct a comprehensive comparative analysis of kinesins in plant and non-plant systems and infer their evolutionary relationships. Results We used the kinesin motor domain to identify kinesins in the completed genome sequences of 19 species, including 13 newly sequenced genomes. Among the newly analyzed genomes, six represent photosynthetic eukaryotes. A total of 529 kinesins was used to perform comprehensive analysis of kinesins and to construct gene trees using the Bayesian and parsimony approaches. The previously recognized 14 families of kinesins are resolved as distinct lineages in our inferred gene tree. At least three of the 14 kinesin families are not represented in flowering plants. Chlamydomonas, a green alga that is part of the lineage that includes land plants, has at least nine of the 14 known kinesin families. Seven of ten families present in flowering plants are represented in Chlamydomonas, indicating that these families were retained in both the flowering-plant and green algae lineages. Conclusion The increase in the number of kinesins in flowering plants is due to vast expansion of the Kinesin-14 and Kinesin-7 families. The Kinesin-14 family, which typically contains a C-terminal motor, has many plant kinesins that have the motor domain at the N terminus, in the middle, or the C terminus. Several domains in kinesins are present exclusively either in plant or animal lineages. Addition of novel domains to kinesins in lineage-specific groups contributed to the

  4. Adult acclimation to combined temperature and pH stressors significantly enhances reproductive outcomes compared to short-term exposures.

    PubMed

    Suckling, Coleen C; Clark, Melody S; Richard, Joelle; Morley, Simon A; Thorne, Michael A S; Harper, Elizabeth M; Peck, Lloyd S

    2015-05-01

    This study examined the effects of long-term culture under altered conditions on the Antarctic sea urchin, Sterechinus neumayeri. Sterechinus neumayeri was cultured under the combined environmental stressors of lowered pH (-0.3 and -0.5 pH units) and increased temperature (+2 °C) for 2 years. This time-scale covered two full reproductive cycles in this species and analyses included studies on both adult metabolism and larval development. Adults took at least 6-8 months to acclimate to the altered conditions, but beyond this, there was no detectable effect of temperature or pH. Animals were spawned after 6 and 17 months exposure to altered conditions, with markedly different outcomes. At 6 months, the percentage hatching and larval survival rates were greatest in the animals kept at 0 °C under current pH conditions, whilst those under lowered pH and +2 °C performed significantly less well. After 17 months, performance was not significantly different across treatments, including controls. However, under the altered conditions urchins produced larger eggs compared with control animals. These data show that under long-term culture adult S. neumayeri appear to acclimate their metabolic and reproductive physiology to the combined stressors of altered pH and increased temperature, with relatively little measureable effect. They also emphasize the importance of long-term studies in evaluating effects of altered pH, particularly in slow developing marine species with long gonad maturation times, as the effects of altered conditions cannot be accurately evaluated unless gonads have fully matured under the new conditions.

  5. Spatial Exposure Analysis for Threatened and Endangered Species from Changing Pesticide Use Pattern in Southern Georgia

    EPA Science Inventory

    In recent decades, pesticide use patterns and crop distributions have changed; however, because there has not been a significant increase in usage disclosures, it is difficult to estimate the changes in potential exposure zones, this analysis focuses on the intersection of agricu...

  6. Discussion about modeling the effects of neutron flux exposure for nuclear reactor core analysis

    SciTech Connect

    Vondy, D.R.

    1986-04-01

    Methods used to calculate the effects of exposure to a neutron flux are described. The modeling of the nuclear-reactor core history presents an analysis challenge. The nuclide chain equations must be solved, and some of the methods in use for this are described. Techniques for treating reactor-core histories are discussed and evaluated.

  7. GENOMIC ANALYSIS OF SURROGATE TISSUES FOR ASSESSING ENVIRONMENTAL EXPOSURES AND FUTURE DISEASE STATES

    EPA Science Inventory

    Genomic Analysis of Surrogate Tissues for Assessing Environmental Exposures and Future Disease States

    John C. Rockett, Chad R. Blystone, Amber K. Goetz, Rachel N. Murrell, Hongzu Ren, Judith E. Schmid, Jessica Stapelfeldt, Lillian F. Strader, Kary E. Thompson, Douglas B. T...

  8. Feeling Validated versus Being Correct: A Meta-Analysis of Selective Exposure to Information

    ERIC Educational Resources Information Center

    Hart, William; Albarracin, Dolores; Eagly, Alice H.; Brechan, Inge; Lindberg, Matthew J.; Merrill, Lisa

    2009-01-01

    A meta-analysis assessed whether exposure to information is guided by defense or accuracy motives. The studies examined information preferences in relation to attitudes, beliefs, and behaviors in situations that provided choices between congenial information, which supported participants' pre-existing attitudes, beliefs, or behaviors, and…

  9. A Meta-Analysis Summarizing the Effects of Pornography II: Aggression after Exposure.

    ERIC Educational Resources Information Center

    Allen, Mike; And Others

    1995-01-01

    Examines by meta-analysis the effect that exposure to pornography produces on aggressive behavior under laboratory conditions considering a variety of possible moderating conditions. Demonstrates a homogeneous set of results showing that pictorial nudity reduces subsequent violent behavior, but that depictions of nonviolent sexual behavior and…

  10. GENOMIC AND PROTEOMIC ANALYSIS OF SURROGATE TISSUES FOR ASSESSING TOXIC EXPOSURES AND DISEASE STATES

    EPA Science Inventory

    Genomic and Proteomic Analysis of Surrogate Tissues for Assessing Toxic Exposures and Disease States
    David J. Dix and John C. Rockett
    Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, USEPA, ...

  11. Railway noise annoyance: exposure-response relationships and testing a theoretical model by structural equation analysis.

    PubMed

    Pennig, Sibylle; Schady, Arthur

    2014-01-01

    In some regions the exposure to railway noise is extremely concentrated, which may lead to high residential annoyance. Nonacoustical factors contribute to these reactions, but there is limited evidence on the interrelations between the nonacoustical factors that influence railway noise annoyance. The aims of the present study were (1) to examine exposure-response relationships between long-term railway noise exposure and annoyance in a region severely affected by railway noise and (2) to determine a priori proposed interrelations between nonacoustical factors by structural equation analysis. Residents (n = 320) living close to railway tracks in the Middle Rhine Valley completed a socio-acoustic survey. Individual noise exposure levels were calculated by an acoustical simulation model for this area. The derived exposure-response relationships indicated considerably higher annoyance at the same noise exposure level than would have been predicted by the European Union standard curve, particularly for the night-time period. In the structural equation analysis, 72% of the variance in noise annoyance was explained by the noise exposure (L(den)) and nonacoustical variables. The model provides insights into several causal mechanisms underlying the formation of railway noise annoyance considering indirect and reciprocal effects. The concern about harmful effects of railway noise and railway traffic, the perceived control and coping capacity, and the individual noise sensitivity were the most important factors that influence noise annoyance. All effects of the nonacoustical factors on annoyance were mediated by the perceived control and coping capacity and additionally proposed indirect effects of the theoretical model were supported by the data.

  12. Hierarchical cluster analysis for exposure assessment of workers in the Semiconductor Health Study.

    PubMed

    Hines, C J; Selvin, S; Samuels, S J; Hammond, S K; Woskie, S R; Hallock, M F; Schenker, M B

    1995-12-01

    The fabrication of integrated circuits in the semiconductor industry involves worker exposures to multiple chemical and physical agents. The potential for a high degree of correlation among exposure variables was of concern in the Semiconductor Health Study. Hierarchical cluster analysis was used to identify groups or "clusters" of correlated variables. Several variations of hierarchical cluster analysis were performed on 14 chemical and physical agents, using exposure data on 882 subjects from the historical cohort of the epidemiological studies. Similarity between agent pairs was determined by calculating two metrics of dissimilarity, and hierarchical trees were constructed using three clustering methods. Among subjects exposed to ethylene-based glycol ethers (EGE), xylene, or n-butyl acetate (nBA), 83% were exposed to EGE and xylene, 86% to EGE and nBA, and 94% to xylene and nBA, suggesting that exposures to EGE, xylene, and nBA were highly correlated. A high correlation was also found for subjects exposed to boron and phosphorus (80%). The trees also revealed cluster groups containing agents associated with work-group exposure categories developed for the epidemiologic analyses.

  13. Phylogeny and comparative genome analysis of a Basidiomycete fungi

    SciTech Connect

    Riley, Robert W.; Salamov, Asaf; Grigoriev, Igor; Hibbett, David

    2011-03-14

    Fungi of the phylum Basidiomycota, make up some 37percent of the described fungi, and are important from the perspectives of forestry, agriculture, medicine, and bioenergy. This diverse phylum includes the mushrooms, wood rots, plant pathogenic rusts and smuts, and some human pathogens. To better understand these important fungi, we have undertaken a comparative genomic analysis of the Basidiomycetes with available sequenced genomes. We report a phylogeny that sheds light on previously unclear evolutionary relationships among the Basidiomycetes. We also define a `core proteome? based on protein families conserved in all Basidiomycetes. We identify key expansions and contractions in protein families that may be responsible for the degradation of plant biomass such as cellulose, hemicellulose, and lignin. Finally, we speculate as to the genomic changes that drove such expansions and contractions.

  14. Comparative proteomics analysis of spermary and ovary in Hyriopsis schlegelii.

    PubMed

    Shi, Jianwu; Wang, Dexia; Zhou, Yan; Gu, Yiran; Wu, Di; Wang, Junhua; Hong, Yijiang

    2017-03-01

    We provide the first large-scale quantitative proteomics analysis in Hyriopsis schlegelii. To investigate the proteins expressed in the gonads, a quantitative proteomics approach has been utilized to analyze differentially expressed proteins between the spermary and ovary. In this study, we identified and quantified 2416 proteins in the gonads of Hyriopsis schlegelii. Of these, 559 proteins showed significantly different expression between the spermary and ovary. Some specific proteins expressed in either the spermary or ovary were identified in Hyriopsis schlegelii. In addition, a series of proteins related to gametogenesis were also identified. Compared with previous reports, many proteins in Hyriopsis schlegelii identified here have different expression patterns between the spermary and ovary. The special hermaphroditism in Hyriopsis schlegelii may contribute to these inconsistent results. The provided proteomics data could be considered as a starting point for subsequent studies focusing on the proteins involved in sexual gland development and maturity.

  15. Comparative Analysis on Nuclear Fuel Sustainability Aspect of FBR

    NASA Astrophysics Data System (ADS)

    Permana, Sidik; Irwanto, Dwi; Suzuki, Mitsutoshi; Saito, Masaki

    2017-01-01

    Recycle program of spent nuclear fuel (SNF) will have some challanges in term of fuel cycle capability and its facilities as well as nuclear non-proliferation concern of special nuclear materials. A different analysis approach as a comparative study have been analyzed based on breeding ratio and heavy metal inventory ratio concepts in fast breeder reactor (FBR) type. Breeding ratio and heavy metal inventory obtain higher than unity which shows breeding gain or surplus inventory of heavy metals are obtained. Breeding ratio indicates the fuel conversion capability from conversion process of fertile materials into fissile material such as fertile materials of U-238, Pu-238, Pu-240 and fissile materials of Pu-239 and Pu-241. Inventory ratio approaches are appropriate to estimate some selected actinide as a mass inventory production such as plutonium inventory ratio which estimate the surplus mass inventory from the ratio of produced plutonium at the net of operation to the initial inventory ratio.

  16. A comparative analysis of soft computing techniques for gene prediction.

    PubMed

    Goel, Neelam; Singh, Shailendra; Aseri, Trilok Chand

    2013-07-01

    The rapid growth of genomic sequence data for both human and nonhuman species has made analyzing these sequences, especially predicting genes in them, very important and is currently the focus of many research efforts. Beside its scientific interest in the molecular biology and genomics community, gene prediction is of considerable importance in human health and medicine. A variety of gene prediction techniques have been developed for eukaryotes over the past few years. This article reviews and analyzes the application of certain soft computing techniques in gene prediction. First, the problem of gene prediction and its challenges are described. These are followed by different soft computing techniques along with their application to gene prediction. In addition, a comparative analysis of different soft computing techniques for gene prediction is given. Finally some limitations of the current research activities and future research directions are provided.

  17. Imaging hydrated microbial extracellular polymers: Comparative analysis by electron microscopy

    SciTech Connect

    Dohnalkova, A.C.; Marshall, M. J.; Arey, B. W.; Williams, K. H.; Buck, E. C.; Fredrickson, J. K.

    2011-01-01

    Microbe-mineral and -metal interactions represent a major intersection between the biosphere and geosphere but require high-resolution imaging and analytical tools for investigating microscale associations. Electron microscopy has been used extensively for geomicrobial investigations and although used bona fide, the traditional methods of sample preparation do not preserve the native morphology of microbiological components, especially extracellular polymers. Herein, we present a direct comparative analysis of microbial interactions using conventional electron microscopy approaches of imaging at room temperature and a suite of cryogenic electron microscopy methods providing imaging in the close-to-natural hydrated state. In situ, we observed an irreversible transformation of the hydrated bacterial extracellular polymers during the traditional dehydration-based sample preparation that resulted in their collapse into filamentous structures. Dehydration-induced polymer collapse can lead to inaccurate spatial relationships and hence could subsequently affect conclusions regarding nature of interactions between microbial extracellular polymers and their environment.

  18. Comparative analysis of DG and solar PV water pumping system

    NASA Astrophysics Data System (ADS)

    Tharani, Kusum; Dahiya, Ratna

    2016-03-01

    Looking at present day electricity scenario, there is a major electricity crisis in rural areas. The farmers are still dependant on the monsoon rains for their irrigation needs and livestock maintenance. Some of the agrarian population has opted to use Diesel Generators for pumping water in their fields. But taking into consideration the economics and environmental conditions, the above choice is not suitable for longer run. An effort to shift from non-renewable sources such as diesel to renewable energy source such as solar has been highlighted. An approximate comparative analysis showing the life cycle costs of a PV pumping system with Diesel Generator powered water pumping is done using MATLAB/STMULTNK.

  19. Cardiovascular disease research in Latin America: A comparative bibliometric analysis

    PubMed Central

    Jahangir, Eiman; Comandé, Daniel; Rubinstein, Adolfo

    2011-01-01

    AIM: To investigate the number of publications in cardiovascular disease (CVD) in Latin America and the Caribbean over the last decade. METHODS: We performed a bibliometric analysis in PubMed from 2001 to 2010 for Latin America and the Caribbean, the United States, Canada, Europe, China, and India. RESULTS: Latin America published 4% of articles compared with 26% from the United States/Canada and 42% from Europe. In CVD, Latin America published 4% of articles vs 23% from the United States/Canada and 40% from Europe. The number of publications in CVD in Latin America increased from 41 in 2001 to 726 in 2010. CONCLUSION: Latin America, while publishing more articles than previously, lags behind developed countries. Further advances in research infrastructure are necessary to develop prevention strategies for this region. PMID:22216374

  20. Comparative dynamic analysis of the full Grossman model.

    PubMed

    Ried, W

    1998-08-01

    The paper applies the method of comparative dynamic analysis to the full Grossman model. For a particular class of solutions, it derives the equations implicitly defining the complete trajectories of the endogenous variables. Relying on the concept of Frisch decision functions, the impact of any parametric change on an endogenous variable can be decomposed into a direct and an indirect effect. The focus of the paper is on marginal changes in the rate of health capital depreciation. It also analyses the impact of either initial financial wealth or the initial stock of health capital. While the direction of most effects remains ambiguous in the full model, the assumption of a zero consumption benefit of health is sufficient to obtain a definite for any direct or indirect effect.

  1. Comparative transcriptome analysis reveals vertebrate phylotypic period during organogenesis

    PubMed Central

    Irie, Naoki; Kuratani, Shigeru

    2011-01-01

    One of the central issues in evolutionary developmental biology is how we can formulate the relationships between evolutionary and developmental processes. Two major models have been proposed: the 'funnel-like' model, in which the earliest embryo shows the most conserved morphological pattern, followed by diversifying later stages, and the 'hourglass' model, in which constraints are imposed to conserve organogenesis stages, which is called the phylotypic period. Here we perform a quantitative comparative transcriptome analysis of several model vertebrate embryos and show that the pharyngula stage is most conserved, whereas earlier and later stages are rather divergent. These results allow us to predict approximate developmental timetables between different species, and indicate that pharyngula embryos have the most conserved gene expression profiles, which may be the source of the basic body plan of vertebrates. PMID:21427719

  2. Analysis of Nerve Agent Metabolites from Hair for Long-Term Verification of Nerve Agent Exposure.

    PubMed

    Appel, Amanda S; McDonough, John H; McMonagle, Joseph D; Logue, Brian A

    2016-06-21

    Several methods for the bioanalysis of nerve agents or their metabolites have been developed for the verification of nerve agent exposure. However, parent nerve agents and known metabolites are generally rapidly excreted from biological matrixes typically used for analysis (i.e., blood, urine, and tissues), limiting the amount of time after an exposure that verification is feasible. In this study, hair was evaluated as a long-term repository of nerve agent hydrolysis products. Pinacolyl methylphosphonic acid (PMPA; hydrolysis product of soman) and isopropyl methylphosphonic acid (IMPA; hydrolysis product of sarin) were extracted from hair samples with N,N-dimethylformamide and subsequently analyzed by liquid chromatography-tandem mass spectrometry. Limits of detection for PMPA and IMPA were 0.15 μg/kg and 7.5 μg/kg and linear ranges were 0.3-150 μg/kg and 7.5-750 μg/kg, respectively. To evaluate the applicability of the method to verify nerve agent exposure well after the exposure event, rats were exposed to soman, hair was collected after approximately 30 days, and stored for up to 3.5 years prior to initial analysis. PMPA was positively identified in 100% of the soman-exposed rats (N = 8) and was not detected in any of the saline treated animals (N = 6). The hair was reanalyzed 5.5 years after exposure and PMPA was detected in 6 of the 7 (one of the soman-exposed hair samples was completely consumed in the analysis at 3.5 years) rat hair samples (with no PMPA detected in the saline exposed animals). Although analysis of CWA metabolites from hair via this technique is not appropriate as a universal method to determine exposure (i.e., it takes time for the hair to grow above the surface of the skin and typical analysis times are >24 h), it complements existing methods and could become the preferred method for verification of exposure if 10 or more days have elapsed after a suspected exposure.

  3. Comparative expression pathway analysis of human and canine mammary tumors

    PubMed Central

    Uva, Paolo; Aurisicchio, Luigi; Watters, James; Loboda, Andrey; Kulkarni, Amit; Castle, John; Palombo, Fabio; Viti, Valentina; Mesiti, Giuseppe; Zappulli, Valentina; Marconato, Laura; Abramo, Francesca; Ciliberto, Gennaro; Lahm, Armin; La Monica, Nicola; de Rinaldis, Emanuele

    2009-01-01

    Background Spontaneous tumors in dog have been demonstrated to share many features with their human counterparts, including relevant molecular targets, histological appearance, genetics, biological behavior and response to conventional treatments. Mammary tumors in dog therefore provide an attractive alternative to more classical mouse models, such as transgenics or xenografts, where the tumour is artificially induced. To assess the extent to which dog tumors represent clinically significant human phenotypes, we performed the first genome-wide comparative analysis of transcriptional changes occurring in mammary tumors of the two species, with particular focus on the molecular pathways involved. Results We analyzed human and dog gene expression data derived from both tumor and normal mammary samples. By analyzing the expression levels of about ten thousand dog/human orthologous genes we observed a significant overlap of genes deregulated in the mammary tumor samples, as compared to their normal counterparts. Pathway analysis of gene expression data revealed a great degree of similarity in the perturbation of many cancer-related pathways, including the 'PI3K/AKT', 'KRAS', 'PTEN', 'WNT-beta catenin' and 'MAPK cascade'. Moreover, we show that the transcriptional relationships between different gene signatures observed in human breast cancer are largely maintained in the canine model, suggesting a close interspecies similarity in the network of cancer signalling circuitries. Conclusion Our data confirm and further strengthen the value of the canine mammary cancer model and open up new perspectives for the evaluation of novel cancer therapeutics and the development of prognostic and diagnostic biomarkers to be used in clinical studies. PMID:19327144

  4. Extreme storm surges: a comparative study of frequency analysis approaches

    NASA Astrophysics Data System (ADS)

    Hamdi, Y.; Bardet, L.; Duluc, C.-M.; Rebour, V.

    2013-11-01

    In France, nuclear facilities were designed to very low probabilities of failure. Nevertheless, exceptional climatic events have given rise to surges much larger than observations (outliers) and had clearly illustrated the potential to underestimate the extreme water levels calculated with the current statistical methods. The objective of the present work is to conduct a comparative study of three approaches including the Annual Maxima (AM), the Peaks-Over Threshold (POT) and the r-Largest Order Statistics (r-LOS). These methods are illustrated in a real analysis case study. All the data sets were screened for outliers. Non-parametric tests for randomness, homogeneity and stationarity of time series were used. The shape and scale parameters stability plots, the mean excess residual life plot and the stability of the standard errors of return levels were used to select optimal thresholds and r values for the POT and r-LOS method, respectively. The comparison of methods was based on: (i) the uncertainty degrees, (ii) the adequacy criteria and tests and (iii) the visual inspection. It was found that the r-LOS and POT methods have reduced the uncertainty on the distributions parameters and return level estimates and have systematically shown values of the 100 and 500 yr return levels smaller than those estimated with the AM method. Results have also shown that none of the compared methods has allowed a good fitting at the right tail of the distribution in the presence of outliers. As a perspective, the use of historical information was proposed in order to increase the representativity of outliers in data sets. Findings are of practical relevance not only to nuclear energy operators in France, for applications in storm surge hazard analysis and flood management, but also for the optimal planning and design of facilities to withstand extreme environmental conditions, with an appropriate level of risk.

  5. A comparative analysis of GPU implementations of spectral unmixing algorithms

    NASA Astrophysics Data System (ADS)

    Sanchez, Sergio; Plaza, Antonio

    2011-11-01

    Spectral unmixing is a very important task for remotely sensed hyperspectral data exploitation. It involves the separation of a mixed pixel spectrum into its pure component spectra (called endmembers) and the estimation of the proportion (abundance) of each endmember in the pixel. Over the last years, several algorithms have been proposed for: i) automatic extraction of endmembers, and ii) estimation of the abundance of endmembers in each pixel of the hyperspectral image. The latter step usually imposes two constraints in abundance estimation: the non-negativity constraint (meaning that the estimated abundances cannot be negative) and the sum-toone constraint (meaning that the sum of endmember fractional abundances for a given pixel must be unity). These two steps comprise a hyperspectral unmixing chain, which can be very time-consuming (particularly for high-dimensional hyperspectral images). Parallel computing architectures have offered an attractive solution for fast unmixing of hyperspectral data sets, but these systems are expensive and difficult to adapt to on-board data processing scenarios, in which low-weight and low-power integrated components are essential to reduce mission payload and obtain analysis results in (near) real-time. In this paper, we perform an inter-comparison of parallel algorithms for automatic extraction of pure spectral signatures or endmembers and for estimation of the abundance of endmembers in each pixel of the scene. The compared techniques are implemented in graphics processing units (GPUs). These hardware accelerators can bridge the gap towards on-board processing of this kind of data. The considered algorithms comprise the orthogonal subspace projection (OSP), iterative error analysis (IEA) and N-FINDR algorithms for endmember extraction, as well as unconstrained, partially constrained and fully constrained abundance estimation. The considered implementations are inter-compared using different GPU architectures and hyperspectral

  6. Comparative analysis of hepatocellular carcinoma and cirrhosis gene expression profiles.

    PubMed

    Jiang, Mingming; Zeng, Qingfang; Dai, Suiping; Liang, Huixia; Dai, Fengying; Xie, Xueling; Lu, Kunlin; Gao, Chunfang

    2017-01-01

    Gene expression data of hepatocellular carcinoma (HCC) was compared with that of cirrhosis (C) to identify critical genes in HCC. A total of five gene expression data sets were downloaded from Gene Expression Omnibus. HCC and healthy samples were combined as dataset HCC, whereas cirrhosis samples were included in dataset C. A network was constructed for dataset HCC with the package R for performing Weighted Gene Co‑expression Network Analysis. Modules were identified by cluster analysis with the packages flashClust and dynamicTreeCut. Hub genes were screened out by calculating connectivity. Functional annotations were assigned to the hub genes using the Database for Annotation, Visualization and Integration Discovery, and functional annotation networks were visualized with Cytoscape. Following the exclusion of outlier samples, 394 HCC samples and 47 healthy samples were included in dataset HCC and 233 cirrhosis samples were included in dataset C. A total of 6 modules were identified in the weighted gene co‑expression network of dataset HCC (blue, brown, turquoise, green, red and yellow). Modules blue, brown and turquoise had high preservation whereas module yellow exhibited the lowest preservation. These modules were associated with transcription, mitosis, cation transportation, cation homeostasis, secretion and regulation of cyclase activity. Various hub genes of module yellow were cytokines, including chemokine (C‑C motif) ligand 22 and interleukin‑19, which may be important in the development of HCC. Gene expression profiles of HCC were compared with those of cirrhosis and numerous critical genes were identified, which may contribute to the progression of HCC. Further studies on these genes may improve the understanding of HCC pathogenesis.

  7. Bisphenol A alters gut microbiome: Comparative metagenomics analysis.

    PubMed

    Lai, Keng-Po; Chung, Yan-Tung; Li, Rong; Wan, Hin-Ting; Wong, Chris Kong-Chu

    2016-11-01

    Mounting evidence has shown that an alteration of the gut microbiota is associated with diet, and plays an important role in animal health and metabolic diseases. However, little is known about the influence of environmental contaminants on the gut microbial community. Bisphenol A (BPA), which is widely used for manufacturing plastic products, has recently been classified as an environmental obesogen. Although many studies have demonstrated the metabolic-disrupting effects of BPA on liver and pancreatic functions, the possible effects of this synthetic compound on the metabolic diversity of the intestinal microbiota is unknown. Using 16S rRNA gene sequencing analysis on caecum samples of CD-1 mice, the present study aimed to test the hypothesis that dietary BPA intake may influence the gut microbiota composition and functions, an important attributing factor to development of the metabolic syndrome. A high-fat diet (HFD) and high-sucrose diet (HSD) were included as the positive controls for comparing the changes in the intestinal microbial profiles. Our results demonstrated a significant reduction of species diversity in the gut microbiota of BPA-fed mice. Alpha and beta diversity analyses showed that dietary BPA intake led to a similar gut microbial community structure as that induced by HFD and HSD in mice. In addition, comparative analysis of the microbial communities revealed that both BPA and a HFD favored the growth of Proteobacteria, a microbial marker of dysbiosis. Consistently, growth induction of the family Helicobacteraceae and reduction of the Firmicutes and Clostridia populations were observed in the mice fed BPA or a HFD. Collectively, our study highlighted that the effects of dietary BPA intake on the shift of microbial community structure were similar to those of a HFD and HSD, and revealed microbial markers for the development of diseases associated with an unstable microbiota.

  8. A Systematic Review and Meta-analysis of Childhood Leukemia and Parental Occupational Pesticide Exposure

    PubMed Central

    Wigle, Donald T.; Turner, Michelle C.; Krewski, Daniel

    2009-01-01

    Objectives We conducted a systematic review and meta-analysis of childhood leukemia and parental occupational pesticide exposure. Data sources Searches of MEDLINE (1950–2009) and other electronic databases yielded 31 included studies. Data extraction Two authors independently abstracted data and assessed the quality of each study. Data synthesis Random effects models were used to obtain summary odds ratios (ORs) and 95% confidence intervals (CIs). There was no overall association between childhood leukemia and any paternal occupational pesticide exposure (OR = 1.09; 95% CI, 0.88–1.34); there were slightly elevated risks in subgroups of studies with low total-quality scores (OR = 1.39; 95% CI, 0.99–1.95), ill-defined exposure time windows (OR = 1.36; 95% CI, 1.00–1.85), and exposure information collected after offspring leukemia diagnosis (OR = 1.34; 95% CI, 1.05–1.70). Childhood leukemia was associated with prenatal maternal occupational pesticide exposure (OR = 2.09; 95% CI, 1.51–2.88); this association was slightly stronger for studies with high exposure-measurement-quality scores (OR = 2.45; 95% CI, 1.68–3.58), higher confounder control scores (OR = 2.38; 95% CI, 1.56–3.62), and farm-related exposures (OR = 2.44; 95% CI, 1.53–3.89). Childhood leukemia risk was also elevated for prenatal maternal occupational exposure to insecticides (OR = 2.72; 95% CI, 1.47–5.04) and herbicides (OR = 3.62; 95% CI, 1.28–10.3). Conclusions Childhood leukemia was associated with prenatal maternal occupational pesticide exposure in analyses of all studies combined and in several subgroups. Associations with paternal occupational pesticide exposure were weaker and less consistent. Research needs include improved pesticide exposure indices, continued follow-up of existing cohorts, genetic susceptibility assessment, and basic research on childhood leukemia initiation and progression. PMID:20019898

  9. Comparative genomics analysis in Prunoideae to identify biologically relevant polymorphisms.

    PubMed

    Koepke, Tyson; Schaeffer, Scott; Harper, Artemus; Dicenta, Federico; Edwards, Mark; Henry, Robert J; Møller, Birger L; Meisel, Lee; Oraguzie, Nnadozie; Silva, Herman; Sánchez-Pérez, Raquel; Dhingra, Amit

    2013-09-01

    Prunus is an economically important genus with a wide range of physiological and biological variability. Using the peach genome as a reference, sequencing reads from four almond accessions and one sweet cherry cultivar were used for comparative analysis of these three Prunus species. Reference mapping enabled the identification of many biological relevant polymorphisms within the individuals. Examining the depth of the polymorphisms and the overall scaffold coverage, we identified many potentially interesting regions including hundreds of small scaffolds with no coverage from any individual. Non-sense mutations account for about 70 000 of the 13 million identified single nucleotide polymorphisms (SNPs). Blast2GO analyses on these non-sense SNPs revealed several interesting results. First, non-sense SNPs were not evenly distributed across all gene ontology terms. Specifically, in comparison with peach, sweet cherry is found to have non-sense SNPs in two 1-aminocyclopropane-1-carboxylate synthase (ACS) genes and two 1-aminocyclopropane-1-carboxylate oxidase (ACO) genes. These polymorphisms may be at the root of the nonclimacteric ripening of sweet cherry. A set of candidate genes associated with bitterness in almond were identified by comparing sweet and bitter almond sequences. To the best of our knowledge, this is the first report in plants of non-sense SNP abundance in a genus being linked to specific GO terms.

  10. Medical and nursing clinical decision making: a comparative epistemological analysis.

    PubMed

    Rashotte, Judy; Carnevale, F A

    2004-07-01

    The aim of this article is to explore the complex forms of knowledge involved in diagnostic and interventional decision making by comparing the processes in medicine and nursing, including nurse practitioners. Many authors assert that the practice of clinical decision making involves the application of theoretical knowledge (acquired in the classroom and textbooks) as well as research evidence, upon concrete particular cases. This approach draws on various universal principles and algorithms to facilitate the task. On the other hand, others argue that this involves an intuitive form of judgement that is difficult to teach, one that is acquired principally through experience. In an exploration of these issues, this article consists of three sections. A clarification of terms commonly used when discussing decision making is provided in the first section. In the second section, an epistemological analysis of decision making is presented by examining several perspectives and comparing them for their use in the nursing and medical literature. Bunge's epistemological framework for decision making (based on scientific realism) is explored for its fit with the aims of medicine and nursing. The final section presents a discussion of knowledge utilization and decision making as it relates to the implications for the education and ongoing development of nurse practitioners. It is concluded that Donald Schön's conception of reflective practice best characterizes the skillful conduct of clinical decision making.

  11. Bursaphelenchus xylophilus and B. mucronatus secretomes: a comparative proteomic analysis

    PubMed Central

    Cardoso, Joana M. S.; Anjo, Sandra I.; Fonseca, Luís; Egas, Conceição; Manadas, Bruno; Abrantes, Isabel

    2016-01-01

    The pinewood nematode, Bursaphelenchus xylophilus, recognized as a worldwide major forest pest, is a migratory endoparasitic nematode with capacity to feed on pine tissues and also on fungi colonizing the trees. Bursaphelenchus mucronatus, the closest related species, differs from B. xylophilus on its pathogenicity, making this nematode a good candidate for comparative analyses. Secretome profiles of B. xylophilus and B. mucronatus were obtained and proteomic differences were evaluated by quantitative SWATH-MS. From the 681 proteins initially identified, 422 were quantified and compared between B. xylophilus and B. mucronatus secretomes and from these, 243 proteins were found differentially regulated: 158 and 85 proteins were increased in B. xylophilus and B. mucronatus secretomes, respectively. While increased proteins in B. xylophilus secretome revealed a strong enrichment in proteins with peptidase activity, the increased proteins in B. mucronatus secretome were mainly related to oxidative stress responses. The changes in peptidases were evaluated at the transcription level by RT-qPCR, revealing a correlation between the mRNA levels of four cysteine peptidases with secretion levels. The analysis presented expands our knowledge about molecular basis of B. xylophilus and B. mucronatus hosts interaction and supports the hypothesis of a key role of secreted peptidases in B. xylophilus pathogenicity. PMID:27941947

  12. Comparative Genomics Analysis in Prunoideae to Identify Biologically Relevant Polymorphisms

    PubMed Central

    Koepke, Tyson; Schaeffer, Scott; Harper, Artemus; Dicenta, Federico; Edwards, Mark; Henry, Robert J.; Møller, Birger Lindberg; Meisel, Lee; Oraguzie, Nnadozie; Silva, Herman; Sánchez-Pérez, Raquel; Dhingra, Amit

    2013-01-01

    Prunus is an economically important genus with a wide range of physiological and biological variability. Using the peach genome as a reference, sequencing reads from four almond accessions and one sweet cherry cultivar were used for comparative analysis of these three Prunus species. Reference mapping enabled the identification of many biological relevant polymorphisms within the individuals. Examining the depth of the polymorphisms and the overall scaffold coverage, we identified many potentially interesting regions including hundreds of small scaffolds with no coverage from any individual. Nonsense mutations account for about 70,000 of the 13 million identified single nucleotide polymorphisms (SNPs). Blast2GO analyses on these nonsense SNPs revealed several interesting results. First, nonsense SNPs were not evenly distributed across all gene ontology terms. Specifically, in comparison to peach, sweet cherry is found to have nonsense SNPs in two 1-aminocyclopropane-1-carboxylate synthase (ACS) genes and two 1-aminocyclopropane-1-carboxylate oxidase (ACO) genes. These polymorphisms may be at the root of the non-climacteric ripening of sweet cherry. A set of candidate genes associated with bitterness in almond were identified by comparing sweet and bitter almond sequences. To the best of our knowledge, this is the first report in plants of nonsense SNP abundance in a genus being linked to specific GO terms. PMID:23763653

  13. OGRe: a relational database for comparative analysis of mitochondrial genomes

    PubMed Central

    Jameson, Daniel; Gibson, Andrew P.; Hudelot, Cendrine; Higgs, Paul G.

    2003-01-01

    Organellar Genome Retrieval (OGRe) is a relational database of complete mitochondrial genome sequences for over 250 Metazoan species. OGRe provides a resource for the comparative analysis of mitochondrial genomes at several levels. At the sequence level, OGRe allows the retrieval of any selected set of mitochondrial genes from any selected set of species. Species are classified using a taxonomic system that allows easy selection of related groups of species. Sequence alignments are also available for some species. At the level of individual nucleotides, the system contains information on base frequencies and codon usage frequencies that can be compared between organisms. At the level of whole genomes, OGRe provides several ways of visualizing information on gene order. Diagrams illustrating the genome arrangement can be generated for any selected set of species automatically from the information in the database. Searches can be done based on gene arrangement to find sets of species that have the same order as one another. Diagrams for pairwise comparison of species can be produced that show the positions of break-points in the gene order and use colour to highlight the sections of the genome that have moved. OGRe is available from http://www.bioinf.man.ac.uk/ogre. PMID:12519982

  14. Comparative multiplex dosage analysis in spinocerebellar ataxia type 2 patients.

    PubMed

    Calì, F; Chiavetta, V; Ragalmuto, A; Vinci, M; Ruggeri, G; Schinocca, P; Romano, V

    2013-04-12

    We developed a new application of comparative multiplex dosage analysis (CMDA) for evaluation of the ataxin 2 gene. Expansions of the triplet CAG can cause spinocerebellar ataxia type 2 (SCA2), a neurodegenerative disease with an autosomal-dominant mode of inheritance. Molecular diagnosis of SCA2 is routinely based on the use of conventional PCR to detect the CAG expansion. However, PCR does not amplify an allele with an expansion of many triplets (>80), which is typically found in infantile and juvenile forms of SCA2, thus leading to false negatives. We propose the analysis of the ATXN2 gene by CMDA to complement existing methods currently used for the detection of large expansions of the CAG repeat. Using CMDA, the presence of any longer mutated allele in a heterozygous patient or fetus would be inferred due to dosage variation of the very frequent normal allele #22. CMDA can be completed in 1 day, at very low cost, and would be a useful tool for prenatal diagnosis and for diagnosis of presymptomatic forms of early-onset SCA2.

  15. Comparative analysis of methods for genome-wide nucleosome cartography.

    PubMed

    Quintales, Luis; Vázquez, Enrique; Antequera, Francisco

    2015-07-01

    Nucleosomes contribute to compacting the genome into the nucleus and regulate the physical access of regulatory proteins to DNA either directly or through the epigenetic modifications of the histone tails. Precise mapping of nucleosome positioning across the genome is, therefore, essential to understanding the genome regulation. In recent years, several experimental protocols have been developed for this purpose that include the enzymatic digestion, chemical cleavage or immunoprecipitation of chromatin followed by next-generation sequencing of the resulting DNA fragments. Here, we compare the performance and resolution of these methods from the initial biochemical steps through the alignment of the millions of short-sequence reads to a reference genome to the final computational analysis to generate genome-wide maps of nucleosome occupancy. Because of the lack of a unified protocol to process data sets obtained through the different approaches, we have developed a new computational tool (NUCwave), which facilitates their analysis, comparison and assessment and will enable researchers to choose the most suitable method for any particular purpose. NUCwave is freely available at http://nucleosome.usal.es/nucwave along with a step-by-step protocol for its use.

  16. Comparative analysis of essential genes in prokaryotic genomic islands

    PubMed Central

    Zhang, Xi; Peng, Chong; Zhang, Ge; Gao, Feng

    2015-01-01

    Essential genes are thought to encode proteins that carry out the basic functions to sustain a cellular life, and genomic islands (GIs) usually contain clusters of horizontally transferred genes. It has been assumed that essential genes are not likely to be located in GIs, but systematical analysis of essential genes in GIs has not been explored before. Here, we have analyzed the essential genes in 28 prokaryotes by statistical method and reached a conclusion that essential genes in GIs are significantly fewer than those outside GIs. The function of 362 essential genes found in GIs has been explored further by BLAST against the Virulence Factor Database (VFDB) and the phage/prophage sequence database of PHAge Search Tool (PHAST). Consequently, 64 and 60 eligible essential genes are found to share the sequence similarity with the virulence factors and phage/prophages-related genes, respectively. Meanwhile, we find several toxin-related proteins and repressors encoded by these essential genes in GIs. The comparative analysis of essential genes in genomic islands will not only shed new light on the development of the prediction algorithm of essential genes, but also give a clue to detect the functionality of essential genes in genomic islands. PMID:26223387

  17. Comparative analysis of actigraphy performance in healthy young subjects.

    PubMed

    Bellone, Giannina J; Plano, Santiago A; Cardinali, Daniel P; Chada, Daniel Pérez; Vigo, Daniel E; Golombek, Diego A

    2016-01-01

    Sleep-related health disorders are increasing worldwide; diagnosis and treatment of such sleep diseases are commonly invasive and sometimes unpractical or expensive. Actigraphy has been recently introduced as a tool for the study of sleep and circadian disorders; however, there are several devices that claim to be useful for research and have not been thoroughly tested. This comparative study provides activity, sleep and temperature information regarding several of the most commonly used actigraphers: Micro-Mini Motion Logger; Act Trust; Misfit Flash; Fitbit Flex & Thermochron. Twenty-two healthy young subjects were assessed with five different commercial actigraphs (Micro-Mini Motionlogger Watch, Condor Act Trust, MisFit Flash and Fitbit Flex) and a temperature recorder (Thermochron), and also completed a sleep diary for a week. There were not significant differences in the analysis of rest-activity pattern between devices. Temperature rhythm comparison between the Act Trust and the Thermochron showed significant differences in rhythm percentage (p<0.05) and mesor (p<0.0563) but not in amplitude or acrophase. Although data accessibility and ease of use was very different for the diverse devices, there were no significant differences for sleep onset, total sleep time and sleep efficiency recordings, where applicable. In conclusion, depending on the type of study and analysis desired (as well as cost and compliance of use), we propose some relative advantages for the different actigraphy/temperature recording devices.

  18. Comparative analysis reveals the underlying mechanism of vertebrate seasonal reproduction.

    PubMed

    Ikegami, Keisuke; Yoshimura, Takashi

    2016-02-01

    Animals utilize photoperiodic changes as a calendar to regulate seasonal reproduction. Birds have highly sophisticated photoperiodic mechanisms and functional genomics analysis in quail uncovered the signal transduction pathway regulating avian seasonal reproduction. Birds detect light with deep brain photoreceptors. Long day (LD) stimulus induces secretion of thyroid-stimulating hormone (TSH) from the pars tuberalis (PT) of the pituitary gland. PT-derived TSH locally activates thyroid hormone (TH) in the hypothalamus, which induces gonadotropin-releasing hormone (GnRH) and hence gonadotropin secretion. However, during winter, low temperatures increase serum TH for adaptive thermogenesis, which accelerates germ cell apoptosis by activating the genes involved in metamorphosis. Therefore, TH has a dual role in the regulation of seasonal reproduction. Studies using TSH receptor knockout mice confirmed the involvement of PT-derived TSH in mammalian seasonal reproduction. In addition, studies in mice revealed that the tissue-specific glycosylation of TSH diversifies its function in the circulation to avoid crosstalk. In contrast to birds and mammals, one of the molecular machineries necessary for the seasonal reproduction of fish are localized in the saccus vasculosus from the photoreceptor to the neuroendocrine output. Thus, comparative analysis is a powerful tool to uncover the universality and diversity of fundamental properties in various organisms.

  19. Biodosimetry for High-Dose Exposures Based on Dicentric Analysis in Lymphocytes Released from the G2-Block by Caffeine.

    PubMed

    Karachristou, Ioanna; Karakosta, Maria; Pantelias, Antonio; Hatzi, Vasiliki; Pantelias, Gabriel; Thanassoulas, Angelos; Karaiskos, Pantelis; Dimitriou, Panagiotis; Terzoudi, Georgia I

    2016-12-01

    High-dose assessments using the conventional dicentric assay are essentially restricted to doses up to 5 Gy and only to lymphocytes that succeed to proceed to first post-exposure mitosis. Since G2-checkpoint activation facilitates DNA damage recognition and arrest of damaged cells, caffeine is used to release G2-blocked lymphocytes overcoming the mitotic index and dicentric yield saturation problems, enabling thus dicentric analysis even at high-dose exposures. Using the fluorescence in situ hybridization technique with telomere and centromere peptide nucleic acid probes, the released lymphocytes, identified as metaphases with decondensed chromosomes following 1.5 h caffeine treatment, show increased yield of dicentrics compared to that obtained in lymphocytes that reach metaphase without G2-checkpoint abrogation by caffeine. Here, a 3-h caffeine/colcemid co-treatment before harvesting at 55 h post-exposure is used so that the dicentric analysis using Giemsa staining is based predominantly on lymphocytes released from the G2-block, increasing thus dicentric yield and enabling construction of a dose-response calibration curve with improved precision of high-dose estimates.

  20. Comparative anatomical analysis of the transcallosal-transchoroidal and transcallosal-transforniceal-transchoroidal approaches to the third ventricle.

    PubMed

    Vitorino Araujo, João Luiz; Veiga, José C E; Wen, Hung Tzu; de Andrade, Almir F; Teixeira, Manoel J; Otoch, José P; Rhoton, Albert L; Preul, Mark C; Spetzler, Robert F; Figueiredo, Eberval G

    2016-11-04

    OBJECTIVE Access to the third ventricle is a veritable challenge to neurosurgeons. In this context, anatomical and morphometric studies are useful for establishing the limitations and advantages of a particular surgical approach. The transchoroidal approach is versatile and provides adequate exposure of the middle and posterior regions of the third ventricle. However, the fornix column limits the exposure of the anterior region of the third ventricle. There is evidence that the unilateral section of the fornix column has little effect on cognitive function. This study compared the anatomical exposure afforded by the transforniceal-transchoroidal approach with that of the transchoroidal approach. In addition, a morphometric evaluation of structures that are relevant to and common in the 2 approaches was performed. METHODS The anatomical exposure provided by the transcallosal-transchoroidal and transcallosal-transforniceal-transchoroidal approaches was compared in 8 fresh cadavers, using a neuronavigation system. The working area, microsurgical exposure area, and angular exposure on the longitudinal and transversal planes of 2 anatomical targets (tuber cinereum and cerebral aqueduct) were compared. Additionally, the thickness of the right frontal lobe parenchyma, thickness of the corpus callosum trunk, and longitudinal diameter of the interventricular foramen were measured. The values obtained were submitted to statistical analysis using the Wilcoxon test. RESULTS In the quantitative evaluation, compared with the transchoroidal approach, the transforniceal-transchoroidal approach provided a greater mean working area (transforniceal-transchoroidal 150 ± 11 mm(2); transchoroidal 121 ± 8 mm(2); p < 0.05), larger mean microsurgical exposure area (transforniceal-transchoroidal 101 ± 9 mm(2); transchoroidal 80 ± 5 mm(2); p < 0.05), larger mean angular exposure area on the longitudinal plane for the tuber cinereum (transforniceal-transchoroidal 71° ± 7

  1. Exposure to Organochlorine Pollutants and Type 2 Diabetes: A Systematic Review and Meta-Analysis

    PubMed Central

    Tang, Mengling; Chen, Kun; Yang, Fangxing; Liu, Weiping

    2014-01-01

    Objective Though exposure to organochlorine pollutants (OCPs) is considered a risk factor for type 2 diabetes (T2DM), epidemiological evidence for the association remains controversial. A systematic review and meta-analysis was applied to quantitatively evaluate the association between exposure to OCPs and incidence of T2DM and pool the inconsistent evidence. Design and Methods Publications in English were searched in MEDLINE and WEB OF SCIENCE databases and related reference lists up to August 2013. Quantitative estimates and information regarding study characteristics were extracted from 23 original studies. Quality assessments of external validity, bias, exposure measurement and confounding were performed, and subgroup analyses were conducted to examine the heterogeneity sources. Results We retrieved 23 eligible articles to conduct this meta-analysis. OR (odds ratio) or RR (risk ratio) estimates in each subgroup were discussed, and the strong associations were observed in PCB-153 (OR, 1.52; 95% CI, 1.19–1.94), PCBs (OR, 2.14; 95% CI, 1.53–2.99), and p,p′-DDE (OR, 1.33; 95% CI, 1.15–1.54) based on a random-effects model. Conclusions This meta-analysis provides quantitative evidence supporting the conclusion that exposure to organochlorine pollutants is associated with an increased risk of incidence of T2DM. PMID:25329153

  2. SILAC-based comparative analysis of pathogenic Escherichia coli secretomes.

    PubMed

    Boysen, Anders; Borch, Jonas; Krogh, Thøger Jensen; Hjernø, Karin; Møller-Jensen, Jakob

    2015-09-01

    Comparative studies of pathogenic bacteria and their non-pathogenic counterparts has led to the discovery of important virulence factors thereby generating insight into mechanisms of pathogenesis. Protein-based antigens for vaccine development are primarily selected among unique virulence-related factors produced by the pathogen of interest. However, recent work indicates that proteins that are not unique to the pathogen but instead selectively expressed compared to its non-pathogenic counterpart could also be vaccine candidates or targets for drug development. Modern methods in quantitative proteome analysis have the potential to discover both classes of proteins and hence form an important tool for discovering therapeutic targets. Adherent-invasive Escherichia coli (AIEC) and Enterotoxigenic E. coli (ETEC) are pathogenic variants of E. coli which cause intestinal disease in humans. AIEC is associated with Crohn's disease (CD), a chronic inflammatory condition of the gastrointestinal tract whereas ETEC is the major cause of human diarrhea which affects hundreds of millions annually. In spite of the disease burden associated with these pathogens, effective vaccines conferring long-term protection are still needed. In order to identify proteins with therapeutic potential, we have used mass spectrometry-based Stable Isotope Labeling with Amino acids in Cell culture (SILAC) quantitative proteomics method which allows us to compare the proteomes of pathogenic strains to commensal E. coli. In this study, we grew the pathogenic strains ETEC H10407, AIEC LF82 and the non-pathogenic reference strain E. coli K-12 MG1655 in parallel and used SILAC to compare protein levels in OMVs and culture supernatant. We have identified well-known virulence factors from both AIEC and ETEC, thus validating our experimental approach. In addition we find proteins that are not unique to the pathogenic strains but expressed at levels different from the commensal strain, including the

  3. Latitudinal variations over Australia of the solar UV-radiation exposures for vitamin D3 in shade compared to full sun.

    PubMed

    Turnbull, David J; Parisi, Alfio V

    2010-03-01

    Abstract This paper reports on the variation of UV radiation in full sun and in shade and how this relates to the physiological production of vitamin D(3) for various latitudes. Calibrated spectral measurements were used to measure the UV radiation in the shade of numerous shade environments for varying solar zenith angles and seasons. This was for exposures to the horizontal, 45 degrees and vertical planes for the solar zenith angle (SZA) range of approximately 5 degrees to 80 degrees. For an SZA of approximately 5 degrees, average UV irradiances required for vitamin D(3) production (UV(D3)) were 0.67 W/m(2) and 0.20 W/m(2) for global and for shade with a sky view of greater than 40%, respectively. The best time to expose the human body to UV radiation while using shaded environments with a sky view of greater than 40% for vitamin D(3) synthesis is for SZAs less than approximately 45 degrees. Shade can be used throughout Australia during summer and winter. However, winter exposure times will vary depending on the latitude. Using shade for UV(D3) exposures can reduce total UV-radiation exposure by 37% to 58% compared to full sun UV(D3) exposures. This research indicates that an improved approach to optimize UV-radiation exposures for the production of vitamin D(3) is to use diffuse UV radiation under shade in and around the middle of the day.

  4. IMMUNOTOXICITY AND BIODISTRIBUTION ANALYSIS OF ARSENIC TRIOXIDE IN C57Bl/6 MICE FOLLOWING A TWO-WEEK INHALATION EXPOSURE

    PubMed Central

    Burchiel, Scott W.; Mitchell, Leah A.; Lauer, Fredine T.; Sun, Xi; McDonald, Jacob D.; Hudson, Laurie G.; Liu, Ke Jian

    2010-01-01

    In these studies the immunotoxicity of arsenic trioxide (ATO, As2O3) was evaluated in mice following 14 days of inhalation exposures (nose only, 3 hrs per day) at concentrations of 50 μg/m3 and 1 mg/m3. A biodistribution analysis performed immediately after inhalation exposures revealed highest levels of arsenic in the kidneys, bladder, liver, and lung. Spleen cell levels were comparable to those found in the blood, with the highest concentration of arsenic detected in the spleen being 150 μg/mg tissue following the 1 mg/m3 exposures. No spleen cell cytotoxicity was observed at either of the two exposure levels. There were no changes in spleen cell surface marker expression for B cells, T cells, macrophages, and natural killer (NK) cells. There were also no changes detected in the B cell (LPS-stimulated) and T cell (Con A-stimulated) proliferative responses of spleen cells, and no changes were found in the NK-mediated lysis of Yac-1 target cells. The primary T-dependent antibody response was, however, found to be highly susceptible to ATO suppression. Both the 50 μg/m3 and 1 mg/m3 exposures produced greater than 70% suppression of the humoral immune response to sheep red blood cells. Thus, the primary finding of this study is that the T-dependent humoral immune response is extremely sensitive to suppression by ATO and assessment of humoral immune responses should be considered in evaluating the health effects of arsenic containing agents. PMID:19800901

  5. Gene expression profiles following exposure to a developmental neurotoxicant, Aroclor 1254: Pathway analysis for possible mode(s) of action

    SciTech Connect

    Royland, Joyce E.; Kodavanti, Prasada Rao S.

    2008-09-01

    Epidemiological studies indicate that low levels of polychlorinated biphenyl (PCB) exposure can adversely affect neurocognitive development. In animal models, perturbations in calcium signaling, neurotransmitters, and thyroid hormones have been postulated as potential mechanisms for PCB-induced developmental neurotoxicity. In order to understand the role of these proposed mechanisms and to identify other mechanisms in PCB-induced neurotoxicity, we have chosen a global approach utilizing oligonucleotide microarrays to examine gene expression profiles in the brain following developmental exposure to Aroclor 1254 (0 or 6 mg/kg/day from gestation day 6 through postnatal day (PND) 21) in Long-Evans rats. Gene expression levels in the cerebellum and hippocampus from PNDs 7 and 14 animals were determined on Affymetrix rat 230A{sub 2}.0 chips. In the cerebellum, 87 transcripts were altered at PND7 compared to 27 transcripts at PND14 by Aroclor 1254 exposure, with only one transcript affected at both ages. In hippocampus, 175 transcripts and 50 transcripts were altered at PND7 and PND14, respectively, by Aroclor 1254 exposure with five genes commonly affected. Functional analysis suggests that pathways related to calcium homeostasis (Gng3, Ryr2, Trdn, Cacna1a), intracellular signaling (Camk2d, Stk17b, Pacsin2, Ryr2, Trio, Fert2, Ptk2b), axonal guidance (Lum, Mxd3, Akap11, Gucy1b3), aryl hydrocarbon receptor signaling (Nfia, Col1a2), and transcripts involved in cell proliferation (Gspt2, Cdkn1c, Ptk2b) and differentiation (Ifitm31, Hpca, Zfp260, Igsf4a, Hes5) leading to the development of nervous system were significantly altered by Aroclor 1254 exposure. Of the two brain regions examined, Aroclor 1254-induced genomic changes were greater in the hippocampus than the cerebellum. The genomic data suggests that PCB-induced neurotoxic effects were due to disruption of normal ontogenetic pattern of nervous system growth and development by altering intracellular signaling pathways

  6. Immunotoxicity and biodistribution analysis of arsenic trioxide in C57Bl/6 mice following a 2-week inhalation exposure

    SciTech Connect

    Burchiel, Scott W.; Mitchell, Leah A.; Lauer, Fredine T.; Sun Xi; McDonald, Jacob D.; Hudson, Laurie G.; Liu Kejian

    2009-12-15

    In these studies the immunotoxicity of arsenic trioxide (ATO, As{sub 2}O{sub 3}) was evaluated in mice following 14 days of inhalation exposures (nose only, 3 h per day) at concentrations of 50 mug/m{sup 3} and 1 mg/m{sup 3}. A biodistribution analysis performed immediately after inhalation exposures revealed highest levels of arsenic in the kidneys, bladder, liver, and lung. Spleen cell levels were comparable to those found in the blood, with the highest concentration of arsenic detected in the spleen being 150 mug/g tissue following the 1 mg/m{sup 3} exposures. No spleen cell cytotoxicity was observed at either of the two exposure levels. There were no changes in spleen cell surface marker expression for B cells, T cells, macrophages, and natural killer (NK) cells. There were also no changes detected in the B cell (LPS-stimulated) and T cell (Con A-stimulated) proliferative responses of spleen cells, and no changes were found in the NK-mediated lysis of Yac-1 target cells. The primary T-dependent antibody response was, however, found to be highly susceptible to ATO suppression. Both the 50 mug/m{sup 3} and 1 mg/m{sup 3} exposures produced greater than 70% suppression of the humoral immune response to sheep red blood cells. Thus, the primary finding of this study is that the T-dependent humoral immune response is extremely sensitive to suppression by ATO and assessment of humoral immune responses should be considered in evaluating the health effects of arsenic containing agents.

  7. Occupational exposure to electromagnetic fields and the occurrence of brain tumors. An analysis of possible associations

    SciTech Connect

    Lin, R.S.; Dischinger, P.C.; Conde, J.; Farrell, K.P.

    1985-06-01

    To explore the association between occupation and the occurrence of brain tumor, an epidemiologic study was conducted using data from the death certificates of 951 adult white male Maryland residents who died of brain tumor during the period 1969 through 1982. Compared with the controls, men employed in electricity-related occupations, such as electrician, electric or electronic engineer, and utility company serviceman, were found to experience a significantly higher proportion of primary brain tumors. An increase in the odds ratio for brain tumor was found to be positively related to electromagnetic (EM) field exposure levels. Furthermore, the mean age at death was found to be significantly younger among cases in the presumed high EM-exposure group. These findings suggest that EM exposure may be associated with the pathogenesis of brain tumors, particularly in the promoting stage.

  8. Environmental Polychlorinated Biphenyl Exposure and Breast Cancer Risk: A Meta-Analysis of Observational Studies

    PubMed Central

    Zhang, Jingwen; Huang, Yue; Wang, Xiaoling; Lin, Kun; Wu, Kusheng

    2015-01-01

    Background Association between polychlorinated biphenyl (PCB) exposure and breast cancer risk has been widely studied, but the results remain controversial. We performed a meta-analysis to evaluate the evidences from observational studies on PCB exposure and breast cancer risk. Methods Relevant studies with data on internal PCB dose were identified from PubMed, EMBASE, CBM and CNKI databases through November 2014. Multivariable-adjusted odds ratio (OR) with 95% confidence intervals (CIs) were applied to assess the association between PCB exposure and breast cancer risk. Heterogeneity test, sensitivity analysis, subgroup analysis and publication bias test were also performed. To further explore the association between specific groups of PCB congeners and breast cancer, we examined the PCB congeners classified, according to their structural, biological and pharmacokinetics properties, as group I (potentially estrogenic), group II (potentially anti-estrogenic and immunotoxic, dioxin-like), and group III (phenobarbital, CYP1A and CYP2B inducers, biologically persistent). Results Of 660 studies screened, 25 studies which met criteria were selected, involving a total of 12866 participants (6088 cases and 6778 controls) from eight countries. The results showed that the risk of breast cancer was associated with group II (OR = 1.23, 95% CI: 1.08–1.40) and group III (OR = 1.25, 95% CI: 1.09–1.43) PCBs, but not with group I (OR = 1.10, 95%CI: 0.97–1.24) PCBs or total PCB exposure (OR = 1.09, 95%CI: 0.97–1.22). Conclusions Our meta-analysis based on the selected studies found group II and group III PCB exposure might contribute to the risk of breast cancer. More studies in developing countries with higher PCB levels are needed, as well as studies to explore the relationships between mixtures of organochlorine compounds and breast cancer risk. PMID:26555153

  9. An analysis of employee exposure to organic dust at large-scale composting facilities

    NASA Astrophysics Data System (ADS)

    Sykes, P.; Allen, J. A.; Wildsmith, J. D.; Jones, K. P.

    2009-02-01

    The occupational health implications from exposure to dust, endotoxin and 1-3 β Glucan at commercial composting sites are uncertain. This study aims to establish employee exposure levels to inhalable and respirable dust, endotoxin and 1-3 β Glucan during various operational practices in the composting process. Personal samples were collected and the inhalable and respirable dust fractions were determined by gravimetric analysis. Endotoxin concentrations were determined using a Limulus Amebocyte Lysate assay (LAL). 1-3 β Glucan levels were estimated using a specific blocking agent to establish the contribution that these compounds gave to the original endotoxin assay. Employees' exposure to dust was found to be generally lower than the levels stipulated in the Control of Substances Hazardous to Health Regulations (COSHH) 2002 (as amended), (median inhalable fraction 1.08 mg/m3, min 0.25 mg/m3 max 10.80 mg/m3, median respirable fraction 0.05 mg/m3, min 0.02 mg/m3, max 1.49 mg/m3). Determination of the biological component of the dust showed that employees' exposures to endotoxin were elevated (median 31.5 EU/m3, min 2.00 EU/m3, max 1741.78 EU/m3), particularly when waste was agitated (median 175.0 EU/m3, min 2.03 EU/m3, max 1741.78 EU/m3). Eight out of 32 (25%) of the personal exposure data for endotoxin exceeded the 200 EU/m3 temporary legal limit adopted in the Netherlands and thirteen out of 32 (40.6%) exceeded the suggested 50 EU/m3 guidance level suggested to protect workers from respiratory health effects. A significant correlation was observed between employee inhalable dust exposure and personal endotoxin concentration (r = 0.728, p<0.05) and also personal endotoxin exposure and 1-3 β Glucan concentration (r = 0.817, p<0.05). Further work is needed to explore the possibility of using inhalable dust concentration as a predictor for personal endotoxin exposure. The general dust levels stipulated in the COSHH Regulations 2002 (as amended) are inadequate for

  10. A meta-analysis of leukaemia risk from protracted exposure to low-dose gamma radiation

    PubMed Central

    Schubauer-Berigan, M K

    2010-01-01

    Context More than 400 000 workers annually receive a measurable radiation dose and may be at increased risk of radiation-induced leukaemia. It is unclear whether leukaemia risk is elevated with protracted, low-dose exposure. Objective We conducted a meta-analysis examining the relationship between protracted low-dose ionising radiation exposure and leukaemia. Data sources Reviews by the National Academies and United Nations provided a summary of informative studies published before 2005. PubMed and Embase databases were searched for additional occupational and environmental studies published between 2005 and 2009. Study selection We selected 23 studies that: (1) examined the association between protracted exposures to ionising radiation and leukaemia excluding chronic lymphocytic subtype; (2) were a cohort or nested case–control design without major bias; (3) reported quantitative estimates of exposure; and (4) conducted exposure–response analyses using relative or excess RR per unit exposure. Methods Studies were further screened to reduce information overlap. Random effects models were developed to summarise between-study variance and obtain an aggregate estimate of the excess RR at 100 mGy. Publication bias was assessed by trim and fill and Rosenthal's file drawer methods. Results We found an ERR at 100 mGy of 0.19 (95% CI 0.07 to 0.32) by modelling results from 10 studies and adjusting for publication bias. Between-study variance was not evident (p=0.99). Conclusions Protracted exposure to low-dose gamma radiation is significantly associated with leukaemia. Our estimate agreed well with the leukaemia risk observed among exposed adults in the Life Span Study (LSS) of atomic bomb survivors, providing increased confidence in the current understanding of leukaemia risk from ionising radiation. However, unlike the estimates obtained from the LSS, our model provides a precise, quantitative summary of the direct estimates of excess risk from studies of

  11. Tooth Matrix Analysis for Biomonitoring of Organic Chemical Exposure: Current Status, Challenges, and Opportunities

    PubMed Central

    Andra, Syam S.; Austin, Christine; Arora, Manish

    2015-01-01

    Epidemiological evidence supports associations between prenatal exposure to environmental organic chemicals and childhood health impairments. Unlike the common choice of biological matrices such as urine and blood that can be limited by short half-lives for some chemicals, teeth provide a stable repository for chemicals with half-life in the order of decades. Given the potential of the tooth bio-matrix to study long-term exposures to environmental organic chemicals in human biomonitoring programs, it is important to be aware of possible pitfalls and potential opportunities to improve on the current analytical method for tooth organics analysis. We critically review previous results of studies of this topic. The major drawbacks and challenges in currently practiced concepts and analytical methods in utilizing tooth bio-matrix are (i) no consideration of external (from outer surface) or internal contamination (from micro odontoblast processes), (ii) the misleading assumption that whole ground teeth represent prenatal exposures (latest formed dentine is lipid rich and therefore would absorb and accumulate more organic chemicals), (iii) reverse causality in exposure assessment due to whole ground teeth, and (iv) teeth are a precious bio-matrix and grinding them raises ethical concerns about appropriate use of a very limited resource in exposure biology and epidemiology studies. These can be overcome by addressing the important limitations and possible improvements with the analytical approach associated at each of the following steps (i) tooth sample preparation to retain exposure timing, (ii) organics extraction and pre-concentration to detect ultra-trace levels of analytes, (iii) chromatography separation, (iv) mass spectrometric detection to detect multi-class organics simultaneously, and (v) method validation, especially to exclude chance findings. To highlight the proposed improvements we present findings from a pilot study that utilizes tooth matrix biomarkers to

  12. Association of trauma exposure with proinflammatory activity: a transdiagnostic meta-analysis

    PubMed Central

    Tursich, M; Neufeld, R W J; Frewen, P A; Harricharan, S; Kibler, J L; Rhind, S G; Lanius, R A

    2014-01-01

    Exposure to psychological trauma (for example, childhood/early life adversity, exposure to violence or assault, combat exposure, accidents or natural disasters) is known to increase one's risk of developing certain chronic medical conditions. Clinical and population studies provide evidence of systemic inflammatory activity in trauma survivors with various psychiatric and nonpsychiatric conditions. This transdiagnostic meta-analysis quantitatively integrates the literature on the relationship of inflammatory biomarkers to trauma exposure and related symptomatology. We conducted random effects meta-analyses relating trauma exposure to log-transformed inflammatory biomarker concentrations, using meta-regression models to test the effects of study quality and psychiatric symptomatology on the inflammatory outcomes. Across k=36 independent samples and n=14 991 participants, trauma exposure was positively associated with C-reactive protein (CRP), interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α (mean rs =0.2455, 0.3067, 0.2890, and 0.2998, respectively). No significant relationships were noted with fibrinogen, IL-2, IL-4, IL-8, or IL-10. In meta-regression models, the presence of psychiatric symptoms was a significant predictor of increased effect sizes for IL-1β and IL-6 (β=1.0175 and 0.3568, respectively), whereas study quality assessment scores were associated with increased effect sizes for IL-6 (β=0.3812). Positive correlations between inflammation and trauma exposure across a range of sample types and diagnoses were found. Although reviewed studies spanned an array of populations, research on any one specific psychiatric diagnosis was generally limited to one or two studies. The results suggest that chronic inflammation likely represents one potential mechanism underlying risk of health problems in trauma survivors. PMID:25050993

  13. Tooth matrix analysis for biomonitoring of organic chemical exposure: Current status, challenges, and opportunities.

    PubMed

    Andra, Syam S; Austin, Christine; Arora, Manish

    2015-10-01

    Epidemiological evidence supports associations between prenatal exposure to environmental organic chemicals and childhood health impairments. Unlike the common choice of biological matrices such as urine and blood that can be limited by short half-lives for some chemicals, teeth provide a stable repository for chemicals with half-life in the order of decades. Given the potential of the tooth bio-matrix to study long-term exposures to environmental organic chemicals in human biomonitoring programs, it is important to be aware of possible pitfalls and potential opportunities to improve on the current analytical method for tooth organics analysis. We critically review previous results of studies of this topic. The major drawbacks and challenges in currently practiced concepts and analytical methods in utilizing tooth bio-matrix are (i) no consideration of external (from outer surface) or internal contamination (from micro-odontoblast processes), (ii) the misleading assumption that whole ground teeth represent prenatal exposures (latest formed dentine is lipid rich and therefore would absorb and accumulate more organic chemicals), (iii) reverse causality in exposure assessment due to whole ground teeth, and (iv) teeth are a precious bio-matrix and grinding them raises ethical concerns about appropriate use of a very limited resource in exposure biology and epidemiology studies. These can be overcome by addressing the important limitations and possible improvements with the analytical approach associated at each of the following steps: (i) tooth sample preparation to retain exposure timing, (ii) organics extraction and pre-concentration to detect ultra-trace levels of analytes, (iii) chromatography separation, (iv) mass spectrometric detection to detect multi-class organics simultaneously, and (v) method validation, especially to exclude chance findings. To highlight the proposed improvements we present findings from a pilot study that utilizes tooth matrix biomarkers

  14. Media exposure, internalization of the thin ideal, and body dissatisfaction: comparing Asian American and European American college females.

    PubMed

    Nouri, Mahsa; Hill, Laura G; Orrell-Valente, Joan K

    2011-09-01

    Internalization of the thin ideal mediates the media exposure-body dissatisfaction relation in young adult European American females. There is little related research on Asian Americans. We used structural equations modeling to test: (1) whether media exposure was associated with body dissatisfaction in Asian American young adult females, (2) internalization of the thin ideal mediated any such association, and (3) whether the mediational model provided equivalent fit for European American and Asian American samples. Participants were 287 college females (154 Asian Americans, 133 European Americans). Internalization of the thin ideal explained the media exposure-body dissatisfaction association equally well for both groups. Results suggest that Asian Americans may be employing unhealthy weight control behaviors, and may be prone to developing eating disorders, at rates similar to European American young adult females. Clinicians need to screen carefully for body dissatisfaction, unhealthy weight control behaviors, and eating disorders in Asian American females.

  15. Analysis of the influence of handset phone position on RF exposure of brain tissue.

    PubMed

    Ghanmi, Amal; Varsier, Nadège; Hadjem, Abdelhamid; Conil, Emmanuelle; Picon, Odile; Wiart, Joe

    2014-12-01

    Exposure to mobile phone radio frequency (RF) electromagnetic fields depends on many different parameters. For epidemiological studies investigating the risk of brain cancer linked to RF exposure from mobile phones, it is of great interest to characterize brain tissue exposure and to know which parameters this exposure is sensitive to. One such parameter is the position of the phone during communication. In this article, we analyze the influence of the phone position on the brain exposure by comparing the specific absorption rate (SAR) induced in the head by two different mobile phone models operating in Global System for Mobile Communications (GSM) frequency bands. To achieve this objective, 80 different phone positions were chosen using an experiment based on the Latin hypercube sampling (LHS) to select a representative set of positions. The averaged SAR over 10 g (SAR10 g) in the head, the averaged SAR over 1 g (SAR1 g ) in the brain, and the averaged SAR in different anatomical brain structures were estimated at 900 and 1800 MHz for the 80 positions. The results illustrate that SAR distributions inside the brain area are sensitive to the position of the mobile phone relative to the head. The results also show that for 5-10% of the studied positions the SAR10 g in the head and the SAR1 g in the brain can be 20% higher than the SAR estimated for the standard cheek position and that the Specific Anthropomorphic Mannequin (SAM) model is conservative for 95% of all the studied positions.

  16. A comparative analysis of biclustering algorithms for gene expression data.

    PubMed

    Eren, Kemal; Deveci, Mehmet; Küçüktunç, Onur; Çatalyürek, Ümit V

    2013-05-01

    The need to analyze high-dimension biological data is driving the development of new data mining methods. Biclustering algorithms have been successfully applied to gene expression data to discover local patterns, in which a subset of genes exhibit similar expression levels over a subset of conditions. However, it is not clear which algorithms are best suited for this task. Many algorithms have been published in the past decade, most of which have been compared only to a small number of algorithms. Surveys and comparisons exist in the literature, but because of the large number and variety of biclustering algorithms, they are quickly outdated. In this article we partially address this problem of evaluating the strengths and weaknesses of existing biclustering methods. We used the BiBench package to compare 12 algorithms, many of which were recently published or have not been extensively studied. The algorithms were tested on a suite of synthetic data sets to measure their performance on data with varying conditions, such as different bicluster models, varying noise, varying numbers of biclusters and overlapping biclusters. The algorithms were also tested on eight large gene expression data sets obtained from the Gene Expression Omnibus. Gene Ontology enrichment analysis was performed on the resulting biclusters, and the best enrichment terms are reported. Our analyses show that the biclustering method and its parameters should be selected based on the desired model, whether that model allows overlapping biclusters, and its robustness to noise. In addition, we observe that the biclustering algorithms capable of finding more than one model are more successful at capturing biologically relevant clusters.

  17. Comparative Proteomic Analysis of Two Uveitis Models in Lewis Rats

    PubMed Central

    Pepple, Kathryn L.; Rotkis, Lauren; Wilson, Leslie; Sandt, Angela; Van Gelder, Russell N.

    2015-01-01

    Purpose Inflammation generates changes in the protein constituents of the aqueous humor. Proteins that change in multiple models of uveitis may be good biomarkers of disease or targets for therapeutic intervention. The present study was conducted to identify differentially-expressed proteins in the inflamed aqueous humor. Methods Two models of uveitis were induced in Lewis rats: experimental autoimmune uveitis (EAU) and primed mycobacterial uveitis (PMU). Differential gel electrophoresis was used to compare naïve and inflamed aqueous humor. Differentially-expressed proteins were separated by using 2-D gel electrophoresis and excised for identification with matrix-assisted laser desorption/ionization–time of flight (MALDI-TOF). Expression of select proteins was verified by Western blot analysis in both the aqueous and vitreous. Results The inflamed aqueous from both models demonstrated an increase in total protein concentration when compared to naïve aqueous. Calprotectin, a heterodimer of S100A8 and S100A9, was increased in the aqueous in both PMU and EAU. In the vitreous, S100A8 and S100A9 were preferentially elevated in PMU. Apolipoprotein E was elevated in the aqueous of both uveitis models but was preferentially elevated in EAU. Beta-B2–crystallin levels decreased in the aqueous and vitreous of EAU but not PMU. Conclusions The proinflammatory molecules S100A8 and S100A9 were elevated in both models of uveitis but may play a more significant role in PMU than EAU. The neuroprotective protein β-B2–crystallin was found to decline in EAU. Therapies to modulate these proteins in vivo may be good targets in the treatment of ocular inflammation. PMID:26747776

  18. Comparative Analysis of Genome Sequences Covering the Seven Cronobacter Species

    PubMed Central

    Cummings, Craig A.; Shih, Rita; Degoricija, Lovorka; Rico, Alain; Brzoska, Pius; Hamby, Stephen E.; Masood, Naqash; Hariri, Sumyya; Sonbol, Hana; Chuzhanova, Nadia; McClelland, Michael; Furtado, Manohar R.; Forsythe, Stephen J.

    2012-01-01

    Background Species of Cronobacter are widespread in the environment and are occasional food-borne pathogens associated with serious neonatal diseases, including bacteraemia, meningitis, and necrotising enterocolitis. The genus is composed of seven species: C. sakazakii, C. malonaticus, C. turicensis, C. dublinensis, C. muytjensii, C. universalis, and C. condimenti. Clinical cases are associated with three species, C. malonaticus, C. turicensis and, in particular, with C. sakazakii multilocus sequence type 4. Thus, it is plausible that virulence determinants have evolved in certain lineages. Methodology/Principal Findings We generated high quality sequence drafts for eleven Cronobacter genomes representing the seven Cronobacter species, including an ST4 strain of C. sakazakii. Comparative analysis of these genomes together with the two publicly available genomes revealed Cronobacter has over 6,000 genes in one or more strains and over 2,000 genes shared by all Cronobacter. Considerable variation in the presence of traits such as type six secretion systems, metal resistance (tellurite, copper and silver), and adhesins were found. C. sakazakii is unique in the Cronobacter genus in encoding genes enabling the utilization of exogenous sialic acid which may have clinical significance. The C. sakazakii ST4 strain 701 contained additional genes as compared to other C. sakazakii but none of them were known specific virulence-related genes. Conclusions/Significance Genome comparison revealed that pair-wise DNA sequence identity varies between 89 and 97% in the seven Cronobacter species, and also suggested various degrees of divergence. Sets of universal core genes and accessory genes unique to each strain were identified. These gene sequences can be used for designing genus/species specific detection assays. Genes encoding adhesins, T6SS, and metal resistance genes as well as prophages are found in only subsets of genomes and have contributed considerably to the variation of

  19. Comparative analysis of existing models for power-grid synchronization

    NASA Astrophysics Data System (ADS)

    Nishikawa, Takashi; Motter, Adilson E.

    2015-01-01

    The dynamics of power-grid networks is becoming an increasingly active area of research within the physics and network science communities. The results from such studies are typically insightful and illustrative, but are often based on simplifying assumptions that can be either difficult to assess or not fully justified for realistic applications. Here we perform a comprehensive comparative analysis of three leading models recently used to study synchronization dynamics in power-grid networks—a fundamental problem of practical significance given that frequency synchronization of all power generators in the same interconnection is a necessary condition for a power grid to operate. We show that each of these models can be derived from first principles within a common framework based on the classical model of a generator, thereby clarifying all assumptions involved. This framework allows us to view power grids as complex networks of coupled second-order phase oscillators with both forcing and damping terms. Using simple illustrative examples, test systems, and real power-grid datasets, we study the inherent frequencies of the oscillators as well as their coupling structure, comparing across the different models. We demonstrate, in particular, that if the network structure is not homogeneous, generators with identical parameters need to be modeled as non-identical oscillators in general. We also discuss an approach to estimate the required (dynamical) system parameters that are unavailable in typical power-grid datasets, their use for computing the constants of each of the three models, and an open-source MATLAB toolbox that we provide for these computations.

  20. Does D-Cycloserine Enhance Exposure Therapy for Anxiety Disorders in Humans? A Meta-Analysis

    PubMed Central

    Rodrigues, Helga; Figueira, Ivan; Lopes, Alessandra; Gonçalves, Raquel; Mendlowicz, Mauro Vitor; Coutinho, Evandro Silva Freire; Ventura, Paula

    2014-01-01

    The treatment of anxiety is on the edge of a new era of combinations of pharmacologic and psychosocial interventions. A new wave of translational research has focused on the use of pharmacological agents as psychotherapy adjuvants using neurobiological insights into the mechanism of the action of certain psychological treatments such as exposure therapy. Recently, d-cycloserine (DCS) an antibiotic used to treat tuberculosis has been applied to enhance exposure-based treatment for anxiety and has proved to be a promising, but as yet unproven intervention. The present study aimed to evaluate the efficacy of DCS in the enhancement of exposure therapy in anxiety disorders. A systematic review/meta-analysis was conducted. Electronic searches were conducted in the databases ISI-Web of Science, Pubmed and PsycINFO. We included only randomized, double-blind, placebo-controlled trials with humans, focusing on the role of DCS in enhancing the action of exposure therapy for anxiety disorders. We identified 328 references, 13 studies were included in our final sample: 4 on obsessive-compulsive disorder, 2 on panic disorder, 2 on social anxiety disorder, 2 on posttraumatic stress disorder, one on acrophobia, and 2 on snake phobia. The results of the present meta-analysis show that DCS enhances exposure therapy in the treatment of anxiety disorders (Cohen d =  −0.34; CI: −0.54 to −0.14), facilitating the specific process of extinction of fear. DCS seems to be effective when administered at a time close to the exposure therapy, at low doses and a limited number of times. DCS emerges as a potential new therapeutic approach for patients with refractory anxiety disorders that are unresponsive to the conventional treatments available. When administered correctly, DCS is a promising strategy for augmentation of CBT and could reduce health care costs, drop-out rates and bring faster relief to patients. PMID:24991926

  1. Substance flow analysis and assessment of environmental exposure potential for triclosan in mainland China.

    PubMed

    Huang, Chu-Long; Ma, Hwong-Wen; Yu, Chang-Ping

    2014-11-15

    Triclosan (TCS) is a widely-used antimicrobial agent in many consumer products around the world, and China is a major producer and consumer of TCS. In this study substance flow analysis (SFA) was used to construct a static model of anthropogenic TCS metabolism in China in 2008. The systematic SFA results were used to determine possible exposure pathways and trends in environmental exposure potential through different pathways. TCS discharged in wastewater mainly flowed into surface water sediment, ocean, and soil, where it accumulates in aquatic and agricultural products that may pose a higher risk to human health than brief exposure during consumption. Only 22% of TCS discharged was removed in the built environment with the remainder discharged into the natural environment, indicating that anthropogenic TCS metabolism in China is unsustainable. Per capita TCS consumption increased 209% from 2003 to 2012, resulting in increased discharge and accumulation in the environment. If current trends continue, it will increase to 713 mg capita(-1) yr(-1) in 2015 and 957 mg capita(-1) yr(-1) in 2020. Accordingly, annual environmental exposure potential will increase from 388 mg capita(-1) in 2008 to 557 mg capita(-1) in 2015 and 747 mg capita(-1) in 2020, indicating an increasing trend of exposure to environmental TCS. Results of Pearson correlation analysis suggested that feasible countermeasures to reduce environmental exposure potential for triclosan would include encouraging the development of small cities, raising awareness of health risks, nurturing environmentally-friendly consumer values, and improving the environmental performance of TCS-containing products.

  2. Efficacy of escitalopram compared to citalopram: a meta-analysis.

    PubMed

    Montgomery, Stuart; Hansen, Thomas; Kasper, Siegfried

    2011-03-01

    The aim of this review was to assess the clinical relevance of the relative antidepressant efficacy of escitalopram and citalopram by meta-analysis. Studies in major depressive disorder (MDD) with both escitalopram and citalopram treatment arms were identified. Adult patients had to meet DSM-IV criteria for MDD. The primary outcome measure was the treatment difference in Montgomery-Asberg Depression Rating Scale (MADRS) total score at week 8 (or last assessment if <8 wk). Secondary outcome measures were response (≥ 50% improvement from baseline) and remission (MADRS ≤ 12). A search of the literature and websites found eight randomized controlled trials (RCTs) and onr naturalistic trial, with a total of 2009 patients (escitalopram, n=995; citalopram, n=1014). Escitalopram was significantly more effective than citalopram in overall treatment effect, with an estimated mean treatment difference of 1.7 points at week 8 (or last assessment if <8 wk) on the MADRS (95% CI 0.8-2.6, p=0.0002) (six RCTs used the MADRS), and in responder rate (8.3 percentage points, 95% CI 4.4-12.3) (eight RCTs) and remitter rate (17.6 percentage points, 95% CI 12.1-23.1) analyses (reported for four RCTs), corresponding to number-needed-to-treat (NNT) values of 11.9 (p<0.0001) for response and 5.7 (p<0.0001) for remission. The overall odds ratios were 1.44 (p<0.0003) for response and 1.86 (p<0.0001) for remission, in favour of escitalopram. In this meta-analysis, the statistically significant superior efficacy of escitalopram compared to citalopram was shown to be clinically relevant.

  3. A comparative analysis of metacommunity types in the freshwater realm.

    PubMed

    Heino, Jani; Soininen, Janne; Alahuhta, Janne; Lappalainen, Jyrki; Virtanen, Risto

    2015-04-01

    Most metacommunity studies have taken a direct mechanistic approach, aiming to model the effects of local and regional processes on local communities within a metacommunity. An alternative approach is to focus on emergent patterns at the metacommunity level through applying the elements of metacommunity structure (EMS; Oikos, 97, 2002, 237) analysis. The EMS approach has very rarely been applied in the context of a comparative analysis of metacommunity types of main microbial, plant, and animal groups. Furthermore, to our knowledge, no study has associated metacommunity types with their potential ecological correlates in the freshwater realm. We assembled data for 45 freshwater metacommunities, incorporating biologically highly disparate organismal groups (i.e., bacteria, algae, macrophytes, invertebrates, and fish). We first examined ecological correlates (e.g., matrix properties, beta diversity, and average characteristics of a metacommunity, including body size, trophic group, ecosystem type, life form, and dispersal mode) of the three elements of metacommunity structure (i.e., coherence, turnover, and boundary clumping). Second, based on those three elements, we determined which metacommunity types prevailed in freshwater systems and which ecological correlates best discriminated among the observed metacommunity types. We found that the three elements of metacommunity structure were not strongly related to the ecological correlates, except that turnover was positively related to beta diversity. We observed six metacommunity types. The most common were Clementsian and quasi-nested metacommunity types, whereas Random, quasi-Clementsian, Gleasonian, and quasi-Gleasonian types were less common. These six metacommunity types were best discriminated by beta diversity and the first axis of metacommunity ecological traits, ranging from metacommunities of producer organisms occurring in streams to those of large predatory organisms occurring in lakes. Our results showed

  4. An analysis of collegiate band directors' exposure to sound pressure levels

    NASA Astrophysics Data System (ADS)

    Roebuck, Nikole Moore

    Noise-induced hearing loss (NIHL) is a significant but unfortunate common occupational hazard. The purpose of the current study was to measure the magnitude of sound pressure levels generated within a collegiate band room and determine if those sound pressure levels are of a magnitude that exceeds the policy standards and recommendations of the Occupational Safety and Health Administration (OSHA), and the National Institute of Occupational Safety and Health (NIOSH). In addition, reverberation times were measured and analyzed in order to determine the appropriateness of acoustical conditions for the band rehearsal environment. Sound pressure measurements were taken from the rehearsal of seven collegiate marching bands. Single sample t test were conducted to compare the sound pressure levels of all bands to the noise exposure standards of OSHA and NIOSH. Multiple regression analysis were conducted and analyzed in order to determine the effect of the band room's conditions on the sound pressure levels and reverberation times. Time weighted averages (TWA), noise percentage doses, and peak levels were also collected. The mean Leq for all band directors was 90.5 dBA. The total accumulated noise percentage dose for all band directors was 77.6% of the maximum allowable daily noise dose under the OSHA standard. The total calculated TWA for all band directors was 88.2% of the maximum allowable daily noise dose under the OSHA standard. The total accumulated noise percentage dose for all band directors was 152.1% of the maximum allowable daily noise dose under the NIOSH standards, and the total calculated TWA for all band directors was 93dBA of the maximum allowable daily noise dose under the NIOSH standard. Multiple regression analysis revealed that the room volume, the level of acoustical treatment and the mean room reverberation time predicted 80% of the variance in sound pressure levels in this study.

  5. Diclofenac topical solution compared with oral diclofenac: a pooled safety analysis

    PubMed Central

    Roth, Sanford H; Fuller, Philip

    2011-01-01

    Background Topical nonsteroidal anti-inflammatory drug (NSAID) formulations, which produce less systemic exposure compared with oral formulations, are an option for the management of osteoarthritis (OA). However, the overall safety and efficacy of these agents compared with oral or systemic therapy remains controversial. Methods Two 12-week, double-blind, double-dummy, randomized, controlled, multicenter studies compared the safety and efficacy profiles of diclofenac topical solution (TDiclo) with oral diclofenac (ODiclo). Each study independently showed that TDiclo had similar efficacy to ODiclo. To compare the safety profiles of TDiclo and ODiclo, a pooled safety analysis was performed for 927 total patients who had radiologically confirmed symptomatic OA of the knee. This pooled analysis included patients treated with TDiclo, containing 45.5% dimethyl sulfoxide (DMSO), and those treated with ODiclo. Safety assessments included monitoring of adverse events (AEs), recording of vital signs, dermatologic evaluation of the study knee, and clinical laboratory evaluation. Results AEs occurred in 312 (67.1%) patients using TDiclo versus 298 (64.5%) of those taking ODiclo. The most common AE with TDiclo was dry skin at the application site (24.1% vs 1.9% with ODiclo; P < 0.0001). Fewer gastrointestinal (25.4% vs 39.0%; P < 0.0001) and cardiovascular (1.5% vs 3.5%; P = 0.055) AEs occurred with TDiclo compared with ODiclo. ODiclo was associated with significantly greater increases in liver enzymes and creatinine, and greater decreases in creatinine clearance and hemoglobin (P < 0.001 for all). Conclusions These findings suggest that TDiclo represents a useful alternative to oral NSAID therapy in the management of OA, with a more favorable safety profile. PMID:21811391

  6. A comparative quadrant analysis of turbulence in a plant canopy

    NASA Astrophysics Data System (ADS)

    Yue, Wusi; Meneveau, Charles; Parlange, Marc B.; Zhu, Weihong; van Hout, René; Katz, Joseph

    2007-05-01

    Large-eddy simulation (LES) of turbulence in plant canopies has traditionally been validated using bulk statistical quantities such as mean velocity and variance profiles. However, turbulent exchanges between a plant canopy and the atmosphere are dominated by large-scale coherent structures, and therefore LES must also be validated using statistical tools that are sensitive to details of coherent structures. In this study, LES and measurements using particle image velocimetry (PIV) are compared near the top of the canopy by means of a quadrant-hole analysis of turbulent kinetic energy, vorticity, and dissipation rate. The LES resolves coarse features of individual corn plants and uses the Lagrangian scale-dependent dynamic subgrid model. At the measurement location, there is good agreement between the LES predictions and the field data in terms of most conditionally sampled quantities, confirming the applicability of LES for fundamental studies of vegetation-air interactions and coherent structures. The simulation results confirm that sweeps (the fourth-quadrant events) contribute the largest fraction of turbulent kinetic energy, vorticity, and dissipation rate inside the plant canopy. The magnitudes of the vorticity and dissipation rate at the top of the canopy are highest in the first quadrant (rare events of outward interactions).

  7. Transcription factor motif quality assessment requires systematic comparative analysis

    PubMed Central

    Kibet, Caleb Kipkurui; Machanick, Philip

    2016-01-01

    Transcription factor (TF) binding site prediction remains a challenge in gene regulatory research due to degeneracy and potential variability in binding sites in the genome. Dozens of algorithms designed to learn binding models (motifs) have generated many motifs available in research papers with a subset making it to databases like JASPAR, UniPROBE and Transfac. The presence of many versions of motifs from the various databases for a single TF and the lack of a standardized assessment technique makes it difficult for biologists to make an appropriate choice of binding model and for algorithm developers to benchmark, test and improve on their models. In this study, we review and evaluate the approaches in use, highlight differences and demonstrate the difficulty of defining a standardized motif assessment approach. We review scoring functions, motif length, test data and the type of performance metrics used in prior studies as some of the factors that influence the outcome of a motif assessment. We show that the scoring functions and statistics used in motif assessment influence ranking of motifs in a TF-specific manner. We also show that TF binding specificity can vary by source of genomic binding data. We also demonstrate that information content of a motif is not in isolation a measure of motif quality but is influenced by TF binding behaviour. We conclude that there is a need for an easy-to-use tool that presents all available evidence for a comparative analysis. PMID:27092243

  8. Ion channel gates: comparative analysis of energy barriers.

    PubMed

    Tai, Kaihsu; Haider, Shozeb; Grottesi, Alessandro; Sansom, Mark S P

    2009-04-01

    The energetic profile of an ion translated along the axis of an ion channel should reveal whether the structure corresponds to a functionally open or closed state of the channel. In this study, we explore the combined use of Poisson-Boltzmann electrostatic calculations and evaluation of van der Waals interactions between ion and pore to provide an initial appraisal of the gating state of a channel. This approach is exemplified by its application to the bacterial inward rectifier potassium channel KirBac3.1, where it reveals the closed gate to be formed by a ring of leucine (L124) side chains. We have extended this analysis to a comparative survey of gating profiles, including model hydrophobic nanopores, the nicotinic acetylcholine receptor, and a number of potassium channel structures and models. This enables us to identify three gating regimes, and to show the limitation of this computationally inexpensive method. For a (closed) gate radius of 0.4 nm < R < 0.8 nm, a hydrophobic gate may be present. For a gate radius of 0.2 nm < R < 0.4 nm, both electrostatic and van der Waals interactions will contribute to the barrier height. Below R = 0.2 nm, repulsive van der Waals interactions are likely to dominate, resulting in a sterically occluded gate. In general, the method is more useful when the channel is wider; for narrower channels, the flexibility of the protein may allow otherwise-unsurmountable energetic barriers to be overcome.

  9. A Comparative Analysis of Life-Cycle Assessment Tools for ...

    EPA Pesticide Factsheets

    We identified and evaluated five life-cycle assessment tools that community decision makers can use to assess the environmental and economic impacts of end-of-life (EOL) materials management options. The tools evaluated in this report are waste reduction mode (WARM), municipal solid waste-decision support tool (MSW-DST), solid waste optimization life-cycle framework (SWOLF), environmental assessment system for environmental technologies (EASETECH), and waste and resources assessment for the environment (WRATE). WARM, MSW-DST, and SWOLF were developed for US-specific materials management strategies, while WRATE and EASETECH were developed for European-specific conditions. All of the tools (with the exception of WARM) allow specification of a wide variety of parameters (e.g., materials composition and energy mix) to a varying degree, thus allowing users to model specific EOL materials management methods even outside the geographical domain they are originally intended for. The flexibility to accept user-specified input for a large number of parameters increases the level of complexity and the skill set needed for using these tools. The tools were evaluated and compared based on a series of criteria, including general tool features, the scope of the analysis (e.g., materials and processes included), and the impact categories analyzed (e.g., climate change, acidification). A series of scenarios representing materials management problems currently relevant to c

  10. Comparative analysis of the Monochamus alternatus immune system.

    PubMed

    Zhou, Jiao; Zhao, Li-Lin; Yu, Hai-Ying; Zhang, Wei; Ahmad, Faheem; Hu, Song-Nian; Zou, Zhen; Sun, Jiang-Hua

    2017-03-01

    The pine sawyer beetle, Monochamus alternatus, is regarded as a notorious forest pest in Asia, vectoring an invasive pathogenic nematode, Bursaphelenchus xylophilus, which is known to cause pine wilt disease. However, little sequence information is available for this vector beetle. This hampered the research on its immune system. Based on transcriptome of M. alternatus, we have identified and characterized 194 immunity-related genes in M. alternatus, and compared them with homologues molecules from other species known to exhibit immune responses against invading microbes. The lower number of putative immunity-related genes in M. alternatus were attributed to fewer C-type lectin, serine protease (SP) and anti-microbial peptide (AMP) genes. Phylogenetic analysis revealed that M. alternatus had a unique recognition gene, galectin3, orthologues of which was not identified in Tribolium castaneum, Drosophila melanogastor, Anopheles gambiae, and Apis mellifera. This suggested a lineage-specific gene evolution for coleopteran insects. Our study provides the comprehensive sequence resources of the immunity-related genes of M. alternatus, presenting valuable information for better understanding of the molecular mechanism of innate immunity processes in M. alternatus against B. xylophilus. This article is protected by copyright. All rights reserved.

  11. A Comparative Analysis of Community Wind Power DevelopmentModels

    SciTech Connect

    Bolinger, Mark; Wiser, Ryan; Wind, Tom; Juhl, Dan; Grace, Robert; West, Peter

    2005-05-20

    For years, farmers in the United States have looked with envy on their European counterparts ability to profitably farm the wind through ownership of distributed, utility-scale wind projects. Only within the past few years, however, has farmer- or community-owned windpower development become a reality in the United States. The primary hurdle to this type of development in the United States has been devising and implementing suitable business and legal structures that enable such projects to take advantage of tax-based federal incentives for windpower. This article discusses the limitations of such incentives in supporting farmer- or community-owned wind projects, describes four ownership structures that potentially overcome such limitations, and finally conducts comparative financial analysis on those four structures, using as an example a hypothetical 1.5 MW farmer-owned project located in the state of Oregon. We find that material differences in the competitiveness of each structure do exist, but that choosing the best structure for a given project will largely depend on the conditions at hand; e.g., the ability of the farmer(s) to utilize tax credits, preference for individual versus cooperative ownership, and the state and utility service territory in which the project will be located.

  12. Comparative Analysis of Carbon Monoxide Tolerance among Thermoanaerobacter Species

    PubMed Central

    Alves, Joana I.; Alves, M. Madalena; Plugge, Caroline M.; Stams, Alfons J. M.; Sousa, Diana Z.

    2016-01-01

    An anaerobic thermophilic strain (strain PCO) was isolated from a syngas-converting enrichment culture. Syngas components cannot be used by strain PCO, but the new strain is very tolerant to carbon monoxide (pCO = 1.7 × 105 Pa, 100% CO). 16S rRNA gene analysis and DNA-DNA hybridization revealed that strain PCO is a strain of Thermoanaerobacter thermohydrosulfuricus. The physiology of strain PCO and other Thermoanaerobacter species was compared, focusing on their tolerance to carbon monoxide. T. thermohydrosulfuricus, T. brockii subsp. finnii, T. pseudethanolicus, and T. wiegelii were exposed to increased CO concentrations in the headspace, while growth, glucose consumption and product formation were monitored. Remarkably, glucose conversion rates by Thermoanaerobacter species were not affected by CO. All the tested strains fermented glucose to mainly lactate, ethanol, acetate, and hydrogen, but final product concentrations differed. In the presence of CO, ethanol production was generally less affected, but H2 production decreased with increasing CO partial pressure. This study highlights the CO resistance of Thermoanaerobacter species. PMID:27621723

  13. Comparative analysis of known miRNAs across platyhelminths.

    PubMed

    Jin, Xiaoliang; Lu, Lixia; Su, Hailong; Lou, Zhongzi; Wang, Fang; Zheng, Yadong; Xu, Guo-Tong

    2013-08-01

    MicroRNAs (miRNAs) are a subtype of small regulatory RNAs that are involved in numerous biological processes through small RNA-induced silencing networks. In an attempt to explore the phylogeny of miRNAs across five platyhelminths, we integrated annotated miRNAs and their full genomes. We identified conserved miRNA clusters and, in particular, miR-71/2 was conserved from planarian to parasitic flatworms and was expanded in free-living Schmidtea mediterranea. Analysis of 22 miRNA loci provided compelling evidence that most known miRNAs are conserved across platyhelminths. Meanwhile, we also observed alterations of known protein-coding genes flanking miRNA(s), such as transcriptional direction conversion and locus relocation, in around ~ 41% of 22 known miRNA loci. Compared with Echinococcus multilocularis, the majority of these events occurred in evolution-distant Hymenolepis microstoma, Schistosoma japonicum or/and S. mediterranea. These results imply rearrangement events occurred near the known miRNA loci.

  14. Noncoding RNA gene detection using comparative sequence analysis

    PubMed Central

    Rivas, Elena; Eddy, Sean R

    2001-01-01

    Background Noncoding RNA genes produce transcripts that exert their function without ever producing proteins. Noncoding RNA gene sequences do not have strong statistical signals, unlike protein coding genes. A reliable general purpose computational genefinder for noncoding RNA genes has been elusive. Results We describe a comparative sequence analysis algorithm for detecting novel structural RNA genes. The key idea is to test the pattern of substitutions observed in a pairwise alignment of two homologous sequences. A conserved coding region tends to show a pattern of synonymous substitutions, whereas a conserved structural RNA tends to show a pattern of compensatory mutations consistent with some base-paired secondary structure. We formalize this intuition using three probabilistic "pair-grammars": a pair stochastic context free grammar modeling alignments constrained by structural RNA evolution, a pair hidden Markov model modeling alignments constrained by coding sequence evolution, and a pair hidden Markov model modeling a null hypothesis of position-independent evolution. Given an input pairwise sequence alignment (e.g. from a BLASTN comparison of two related genomes) we classify the alignment into the coding, RNA, or null class according to the posterior probability of each class. Conclusions We have implemented this approach as a program, QRNA, which we consider to be a prototype structural noncoding RNA genefinder. Tests suggest that this approach detects noncoding RNA genes with a fair degree of reliability. PMID:11801179

  15. Comparative analysis of ATRX, a chromatin remodeling protein.

    PubMed

    Park, Daniel J; Pask, Andrew J; Huynh, Kim; Renfree, Marilyn B; Harley, Vincent R; Graves, Jennifer A Marshall

    2004-09-15

    The ATRX protein, associated with X-linked alpha-thalassaemia, mental retardation and developmental abnormalities including genital dysgenesis, has been proposed to function as a global transcriptional regulator within a multi-protein complex. However, an understanding of the composition and mechanics of this machinery has remained elusive. We applied inter-specific comparative analysis to identify conserved elements which may be involved in regulating the conformation of chromatin. As part of this study, we cloned and sequenced the entire translatable coding region (7.4 kb) of the ATRX gene from a model marsupial (tammar wallaby, Macropus eugenii). We identify an ATRX ancestral core, conserved between plants, fish and mammals, comprising the cysteine-rich and SWI2/SNF2 helicase-like regions and protein interaction domains. Our data are consistent with the model of the cysteine-rich region as a DNA-binding zinc finger adjacent to a protein-binding (plant homeodomain-like) domain. Alignment of vertebrate ATRX sequences highlights other conserved elements, including a negatively charged mammalian sequence which we propose to be involved in binding of positively charged histone tails.

  16. Sequencing and comparative analysis of the gorilla MHC genomic sequence.

    PubMed

    Wilming, Laurens G; Hart, Elizabeth A; Coggill, Penny C; Horton, Roger; Gilbert, James G R; Clee, Chris; Jones, Matt; Lloyd, Christine; Palmer, Sophie; Sims, Sarah; Whitehead, Siobhan; Wiley, David; Beck, Stephan; Harrow, Jennifer L

    2013-01-01

    Major histocompatibility complex (MHC) genes play a critical role in vertebrate immune response and because the MHC is linked to a significant number of auto-immune and other diseases it is of great medical interest. Here we describe the clone-based sequencing and subsequent annotation of the MHC region of the gorilla genome. Because the MHC is subject to extensive variation, both structural and sequence-wise, it is not readily amenable to study in whole genome shotgun sequence such as the recently published gorilla genome. The variation of the MHC also makes it of evolutionary interest and therefore we analyse the sequence in the context of human and chimpanzee. In our comparisons with human and re-annotated chimpanzee MHC sequence we find that gorilla has a trimodular RCCX cluster, versus the reference human bimodular cluster, and additional copies of Class I (pseudo)genes between Gogo-K and Gogo-A (the orthologues of HLA-K and -A). We also find that Gogo-H (and Patr-H) is coding versus the HLA-H pseudogene and, conversely, there is a Gogo-DQB2 pseudogene versus the HLA-DQB2 coding gene. Our analysis, which is freely available through the VEGA genome browser, provides the research community with a comprehensive dataset for comparative and evolutionary research of the MHC.

  17. Comparative proteomic analysis of rice shoots exposed to high arsenate.

    PubMed

    Liu, Yanli; Li, Ming; Han, Chao; Wu, Fengxia; Tu, Bingkun; Yang, Pingfang

    2013-10-01

    Consumption of arsenic contaminated water and cereals is a serious threat to humans all over the world. Rice (Oryza sativa "Nipponbare"), as a main cereal crop, can accumulate arsenic more than 10-fold that of in other cereals. To gain a comprehensive understanding of the response of rice subjected to 100 µM arsenate stress, a comparative proteomic analysis of rice shoots in combination with morphological and biochemical investigations have been performed in this study. The results demonstrated that arsenate suppressed the growth of rice seedlings, destroyed the cellular ultra-structure and changed the homeostasis of reactive oxygen species. Moreover, a total of 38 differentially displayed proteins, which were mainly involved in metabolism, redox and protein-metabolism, were identified. The data suggest the arsenic can inhibit rice growth through negatively affecting chloroplast structure and photosynthesis. In addition, upregulation of the proteins involved in redox and protein metabolism might help the rice to be resistant or tolerant to arsenic toxicity. In general, this study improves our understanding about the rice arsenic responsive mechanism.

  18. Comparative analysis of PSO algorithms for PID controller tuning

    NASA Astrophysics Data System (ADS)

    Štimac, Goranka; Braut, Sanjin; Žigulić, Roberto

    2014-09-01

    The active magnetic bearing(AMB) suspends the rotating shaft and maintains it in levitated position by applying controlled electromagnetic forces on the rotor in radial and axial directions. Although the development of various control methods is rapid, PID control strategy is still the most widely used control strategy in many applications, including AMBs. In order to tune PID controller, a particle swarm optimization(PSO) method is applied. Therefore, a comparative analysis of particle swarm optimization(PSO) algorithms is carried out, where two PSO algorithms, namely (1) PSO with linearly decreasing inertia weight(LDW-PSO), and (2) PSO algorithm with constriction factor approach(CFA-PSO), are independently tested for different PID structures. The computer simulations are carried out with the aim of minimizing the objective function defined as the integral of time multiplied by the absolute value of error(ITAE). In order to validate the performance of the analyzed PSO algorithms, one-axis and two-axis radial rotor/active magnetic bearing systems are examined. The results show that PSO algorithms are effective and easily implemented methods, providing stable convergence and good computational efficiency of different PID structures for the rotor/AMB systems. Moreover, the PSO algorithms prove to be easily used for controller tuning in case of both SISO and MIMO system, which consider the system delay and the interference among the horizontal and vertical rotor axes.

  19. Engine System Loads Analysis Compared to Hot-Fire Data

    NASA Technical Reports Server (NTRS)

    Frady, Gregory P.; Jennings, John M.; Mims, Katherine; Brunty, Joseph; Christensen, Eric R.; McConnaughey, Paul R. (Technical Monitor)

    2002-01-01

    Early implementation of structural dynamics finite element analyses for calculation of design loads is considered common design practice for high volume manufacturing industries such as automotive and aeronautical industries. However with the rarity of rocket engine development programs starts, these tools are relatively new to the design of rocket engines. In the NASA MC-1 engine program, the focus was to reduce the cost-to-weight ratio. The techniques for structural dynamics analysis practices, were tailored in this program to meet both production and structural design goals. Perturbation of rocket engine design parameters resulted in a number of MC-1 load cycles necessary to characterize the impact due to mass and stiffness changes. Evolution of loads and load extraction methodologies, parametric considerations and a discussion of load path sensitivities are important during the design and integration of a new engine system. During the final stages of development, it is important to verify the results of an engine system model to determine the validity of the results. During the final stages of the MC-1 program, hot-fire test results were obtained and compared to the structural design loads calculated by the engine system model. These comparisons are presented in this paper.

  20. Study to compare veterinarians’ exposure to Toxoplasma gondii to that of veterinary staff and the general public

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Toxoplasmosis has been epidemiologically linked with the serious mental illness that is schizophrenia. Toxoplasmosis has also been associated with the risk of suicide. The suicide rate in the veterinary population has reached a level of concern. To assess the prevalence of Toxoplasma gondii exposure...

  1. Synthesized Speech Intelligibility and Early Preschool-Age Children: Comparing Accuracy for Single-Word Repetition with Repeated Exposure

    ERIC Educational Resources Information Center

    Pinkoski-Ball, Carrie L.; Reichle, Joe; Munson, Benjamin

    2012-01-01

    Purpose: This investigation examined the effect of repeated exposure to novel and repeated spoken words in typical environments on the intelligibility of 2 synthesized voices and human recorded speech in preschools. Method: Eighteen preschoolers listened to and repeated single words presented in human-recorded speech, DECtalk Paul, and AT&T Voice…

  2. A quantitative analysis of prenatal methyl mercury exposure and cognitive development.

    PubMed

    Cohen, Joshua T; Bellinger, David C; Shaywitz, Bennett A

    2005-11-01

    Although a rich source of n-3 polyunsaturated fatty acids (PUFAs) that may confer multiple health benefits, some fish also contain methyl mercury (MeHg), which may harm the developing fetus. U.S. government recommendations for women of childbearing age are to modify consumption of high MeHg fish to reduce MeHg exposure, while recommendations encourage fish consumption among the general population because of the nutritional benefits. The Harvard Center for Risk Analysis convened an expert panel (see acknowledgements) to quantify the net impact of resulting hypothetical changes in fish consumption across the population. This paper quantifies the impact of prenatal MeHg exposure on cognitive development. Other papers quantify the beneficial impact of prenatal intake of n-3 PUFAs on cognitive function and the extent to which fish consumption protects against coronary heart disease mortality and stroke in adults. This analysis aggregates results from three major prospective epidemiology studies to quantify the association between prenatal MeHg exposure and cognitive development as measured by intelligence quotient (IQ). It finds that prenatal MeHg exposure sufficient to increase the concentration of mercury in maternal hair at parturition by 1 microg/g decreases IQ by 0.7 points. This paper identifies important sources of uncertainty influencing this estimate, concluding that the plausible range of values for this loss is 0 to 1.5 IQ points.

  3. Complexities of sibling analysis when exposures and outcomes change with time and birth order.

    PubMed

    Sudan, Madhuri; Kheifets, Leeka I; Arah, Onyebuchi A; Divan, Hozefa A; Olsen, Jørn

    2014-01-01

    In this study, we demonstrate the complexities of performing a sibling analysis with a re-examination of associations between cell phone exposures and behavioral problems observed previously in the Danish National Birth Cohort. Children (52,680; including 5441 siblings) followed up to age 7 were included. We examined differences in exposures and behavioral problems between siblings and non-siblings and by birth order and birth year. We estimated associations between cell phone exposures and behavioral problems while accounting for the random family effect among siblings. The association of behavioral problems with both prenatal and postnatal exposure differed between siblings (odds ratio (OR): 1.07; 95% confidence interval (CI): 0.69-1.66) and non-siblings (OR: 1.54; 95% CI: 1.36-1.74) and within siblings by birth order; the association was strongest for first-born siblings (OR: 1.72; 95% CI: 0.86-3.42) and negative for later-born siblings (OR: 0.63; 95% CI: 0.31-1.25), which may be because of increases in cell phone use with later birth year. Sibling analysis can be a powerful tool for (partially) accounting for confounding by invariant unmeasured within-family factors, but it cannot account for uncontrolled confounding by varying family-level factors, such as those that vary with time and birth order.

  4. Effects of vehicle-ride exposure on cervical pathology: a meta-analysis.

    PubMed

    Kollock, Roger; Games, Kenneth; Wilson, Alan E; Sefton, JoEllen M

    2015-01-01

    Research to date on the effect vehicle-ride exposure has on the development of cervical pathologies in mounted Warfighters is conflicting. The purpose of this study was to determine if the literature suggests a definite effect of vehicle-ride exposure on cervical pathology. Databases were searched using multiple combinations of select terms. Twelve studies meeting the inclusion criteria were included in the meta-analysis. The results of the meta-analysis revealed that overall vehicle-ride exposure was likely to increase cervical pathology (p=0.01, odds ratio=1.59, 95% CI=1.16-2.17). Using vehicle type as a moderator it was found that vehicle-ride exposure in ground-based vehicles (p=0.01, odds ratio=2.33, 95% CI=1.41-3.85) and fixed-wing aircraft (p=0.01, odds ratio =1.59, 95% CI=1.13-2.23) were likely to increase cervical pathology. Using operator/other personnel moderator it was found that in the populations tested, fighter pilots or fighter jet weapons systems operators were more likely to develop a cervical pathology (p<0.001, odds ratio=1.78, 95% CI=1.26-2.50). The available studies indicate an increase in cervical pathology for personnel exposed to ground-based vehicles and fixed-wing aircraft.

  5. Effects of vehicle-ride exposure on cervical pathology: a meta-analysis

    PubMed Central

    KOLLOCK, Roger; GAMES, Kenneth; WILSON, Alan E.; SEFTON, JoEllen M.

    2015-01-01

    Research to date on the effect vehicle-ride exposure has on the development of cervical pathologies in mounted Warfighters is conflicting. The purpose of this study was to determine if the literature suggests a definite effect of vehicle-ride exposure on cervical pathology. Databases were searched using multiple combinations of select terms. Twelve studies meeting the inclusion criteria were included in the meta-analysis. The results of the meta-analysis revealed that overall vehicle-ride exposure was likely to increase cervical pathology (p=0.01, odds ratio=1.59, 95% CI=1.16−2.17). Using vehicle type as a moderator it was found that vehicle-ride exposure in ground-based vehicles (p=0.01, odds ratio=2.33, 95% CI=1.41−3.85) and fixed-wing aircraft (p=0.01, odds ratio =1.59, 95% CI=1.13−2.23) were likely to increase cervical pathology. Using operator/other personnel moderator it was found that in the populations tested, fighter pilots or fighter jet weapons systems operators were more likely to develop a cervical pathology (p<0.001, odds ratio=1.78, 95% CI=1.26−2.50). The available studies indicate an increase in cervical pathology for personnel exposed to ground-based vehicles and fixed-wing aircraft. PMID:25739897

  6. Head impact exposure in youth football: high school ages 14 to 18 years and cumulative impact analysis.

    PubMed

    Urban, Jillian E; Davenport, Elizabeth M; Golman, Adam J; Maldjian, Joseph A; Whitlow, Christopher T; Powers, Alexander K; Stitzel, Joel D

    2013-12-01

    Sports-related concussion is the most common athletic head injury with football having the highest rate among high school athletes. Traditionally, research on the biomechanics of football-related head impact has been focused at the collegiate level. Less research has been performed at the high school level, despite the incidence of concussion among high school football players. The objective of this study is to twofold: to quantify the head impact exposure in high school football, and to develop a cumulative impact analysis method. Head impact exposure was measured by instrumenting the helmets of 40 high school football players with helmet mounted accelerometer arrays to measure linear and rotational acceleration. A total of 16,502 head impacts were collected over the course of the season. Biomechanical data were analyzed by team and by player. The median impact for each player ranged from 15.2 to 27.0 g with an average value of 21.7 (±2.4) g. The 95th percentile impact for each player ranged from 38.8 to 72.9 g with an average value of 56.4 (±10.5) g. Next, an impact exposure metric utilizing concussion injury risk curves was created to quantify cumulative exposure for each participating player over the course of the season. Impacts were weighted according to the associated risk due to linear acceleration and rotational acceleration alone, as well as the combined probability (CP) of injury associated with both. These risks were summed over the course of a season to generate risk weighted cumulative exposure. The impact frequency was found to be greater during games compared to practices with an average number of impacts per session of 15.5 and 9.4, respectively. However, the median cumulative risk weighted exposure based on combined probability was found to be greater for practices vs. games. These data will provide a metric that may be used to better understand the cumulative effects of repetitive head impacts, injury mechanisms, and head impact exposure of

  7. IMPORTANT EXPOSURE FACTORS FOR CHILDREN AN ANALYSIS OF LABORATORY AND OBSERVATIONAL FIELD DATA CHARACTERIZING CUMULATIVE EXPOSURE TO PESTICIDES

    EPA Science Inventory

    In an effort to facilitate more realistic risk assessments that take into account unique childhood vulnerabilities to environmental toxicants, the U.S. EPA's National Exposure Research Laboratory (NERL) developed a framework for systematically identifying and addressing the most ...

  8. Comparative study of different exposure routes on the biotransformation and genotoxicity of PAHs in the flatfish species, Scophthalmus maximus.

    PubMed

    Le Dû-Lacoste, Marie; Akcha, Farida; Dévier, Marie-Hélène; Morin, Bénédicte; Burgeot, Thierry; Budzinski, Hélène

    2013-02-01

    In this study, laboratory experiments were carried out in order to come to a better understanding of the fate of polycyclic aromatic hydrocarbons (PAHs) in the marine environment and especially on their bioaccumulation, biotransformation and genotoxic effects in fish. Juveniles of turbot (Scophthalmus maximus) were exposed to PAHs through different routes via (1) a mixture of dissolved PAHs, (2) a PAH-polluted sediment and (3) an oil fuel elutriate. Fish were exposed 4 days followed by a 6-day depuration period. In each experiment, PAH concentrations in the seawater of the tanks were analysed regularly by gas chromatography coupled with mass spectrometry. Muscle and liver samples were also analysed for parent PAH levels and PAH bioconcentration factors were calculated. Biotransformation was evaluated by measuring the levels of PAH metabolites in fish bile. Genotoxicity was assessed by the alkaline comet assay. Regardless of exposure route, the parent PAH concentrations in the liver and muscle showed a peak level 1 day after the beginning of the exposure, followed by a decrease up to the background level towards the end of the experiment, except for the exposure to dissolved PAHs for which levels were relatively low throughout the study. As a consequence, no bioaccumulation was observed in fish tissues at the end of the experiment. In contrast, regardless of exposure routes, a rapid production of biliary metabolites was observed throughout the whole exposure experiment. This was especially true for 1-hydroxypyrene, the major metabolite of pyrene. After 6 days of recovery in clean water, a significant decrease in the total metabolite concentrations occurred in bile. Fish exposed through either route displayed a significant increase in DNA strand breaks after 4 days of exposure, and significant correlations were observed between the level of biliary PAH metabolites and the level of DNA lesions in fish erythrocytes. Overall results indicate that exposure to either a

  9. Evaluation of the Tobacco Heating System 2.2. Part 6: 90-day OECD 413 rat inhalation study with systems toxicology endpoints demonstrates reduced exposure effects of a mentholated version compared with mentholated and non-mentholated cigarette smoke.

    PubMed

    Oviedo, Alberto; Lebrun, Stefan; Kogel, Ulrike; Ho, Jenny; Tan, Wei Teck; Titz, Bjoern; Leroy, Patrice; Vuillaume, Gregory; Bera, Monali; Martin, Florian; Rodrigo, Gregory; Esposito, Marco; Dempsey, Ruth; Ivanov, Nikolai V; Hoeng, Julia; Peitsch, Manuel C; Vanscheeuwijck, Patrick

    2016-11-30

    The toxicity of a mentholated version of the Tobacco Heating System (THS2.2M), a candidate modified risk tobacco product (MRTP), was characterized in a 90-day OECD inhalation study. Differential gene and protein expression analysis of nasal epithelium and lung tissue was also performed to record exposure effects at the molecular level. Rats were exposed to filtered air (sham), to THS2.2M (at 15, 23 and 50 μg nicotine/l), to two mentholated reference cigarettes (MRC) (at 23 μg nicotine/l), or to the 3R4F reference cigarette (at 23 μg nicotine/l). MRCs were designed to meet 3R4F specifications. Test atmosphere analyses demonstrated that aldehydes were reduced by 75%-90% and carbon monoxide by 98% in THS2.2M aerosol compared with MRC smoke; aerosol uptake was confirmed by carboxyhemoglobin and menthol concentrations in blood, and by the quantities of urinary nicotine metabolites. Systemic toxicity and alterations in the respiratory tract were significantly lower in THS2.2M-exposed rats compared with MRC and 3R4F. Pulmonary inflammation and the magnitude of the changes in gene and protein expression were also dramatically lower after THS2.2M exposure compared with MRCs and 3R4F. No menthol-related effects were observed after MRC mainstream smoke-exposure compared with 3R4F.

  10. A comparative assessment of PM2.5 exposures in light-rail, subway, freeway, and surface street environments in Los Angeles and estimated lung cancer risk.

    PubMed

    Kam, Winnie; Delfino, Ralph J; Schauer, James J; Sioutas, C

    2013-01-01

    According to the U.S. Census Bureau, 570000+ commuters in Los Angeles travel for over 60 minutes to work. Studies have shown that a substantial portion of particulate matter (PM) exposure can occur during this commute. This study represents the integration of the results from five commute environments in Los Angeles. Personal PM exposures are discussed for the: (1) METRO gold line, a ground-level light-rail route, (2) METRO red line, a subway line, (3) the 110, a high volume freeway with low heavy-duty vehicle (HDV) fraction, (4) the 710, a major corridor for HDVs from the Port of Los Angeles, and (5) Wilshire/Sunset Boulevards, major surface streets. Chemical analysis including total and water-soluble metals and trace elements, elemental and organic carbon (EC/OC), and polycyclic aromatic hydrocarbons (PAHs) was performed. The focus of this study is to compare the composition and estimated lung cancer risk of PM2.5 (dp < 2.5 μm) for the five differential commute environments. Metals associated with stainless steel, notably Fe, Cr, and Mn, were elevated for the red line (subway), most likely from abrasion processes between the rail and brakes; elements associated with tire and brake wear and oil additives (Ca, Ti, Sn, Sb, and Pb) were elevated on roadways. Elemental concentrations on the gold line (light-rail) were the lowest. For water-solubility, metals observed on the red line (subway) were the least soluble. PAHs are primarily derived from vehicular emissions. Overall, the 710 exhibited high levels of PAHs (3.0 ng m−3), most likely due to its high volume of HDVs, while the red and gold lines exhibited low PAH concentrations (0.6 and 0.8 ng m−3 for red and gold lines, respectively). Lastly, lung cancer risk due to inhalation of PAHs was calculated based on a commuter lifetime (45 years for 2 hours per workday). Results showed that lung cancer risk for the 710 is 3.8 and 4.5 times higher than the light-rail (gold line) and subway (red line), respectively

  11. Actual and Potential Radiation Exposures in Digital Radiology: Analysis of Cumulative Data, Implications to Worker Classification and Occupational Exposure Monitoring.

    PubMed

    Kortesniemi, Mika; Siiskonen, Teemu; Kelaranta, Anna; Lappalainen, Kimmo

    2016-04-21

    Radiation worker categorization and exposure monitoring are principal functions of occupational radiation safety. The aim of this study was to use the actual occupational exposure data in a large university hospital to estimate the frequency and magnitude of potential exposures in radiology. The additional aim was to propose a revised categorization and exposure monitoring practice based on the potential exposures. The cumulative probability distribution was calculated from the normalized integral of the probability density function fitted to the exposure data. Conformity of the probabilistic model was checked against 16 years of national monitoring data. The estimated probabilities to exceed annual effective dose limits of 1 mSv, 6 mSv and 20 mSv were 1:1000, 1:20 000 and 1:200 000, respectively. Thus, it is very unlikely that the class A categorization limit of 6 mSv could be exceeded, even in interventional procedures, with modern equipment and appropriate working methods. Therefore, all workers in diagnostic and interventional radiology could be systematically categorized into class B. Furthermore, current personal monitoring practice could be replaced by use of active personal dosemeters that offer more effective and flexible means to optimize working methods.

  12. Statistical correlation analysis for comparing vibration data from test and analysis

    NASA Technical Reports Server (NTRS)

    Butler, T. G.; Strang, R. F.; Purves, L. R.; Hershfeld, D. J.

    1986-01-01

    A theory was developed to compare vibration modes obtained by NASTRAN analysis with those obtained experimentally. Because many more analytical modes can be obtained than experimental modes, the analytical set was treated as expansion functions for putting both sources in comparative form. The dimensional symmetry was developed for three general cases: nonsymmetric whole model compared with a nonsymmetric whole structural test, symmetric analytical portion compared with a symmetric experimental portion, and analytical symmetric portion with a whole experimental test. The theory was coded and a statistical correlation program was installed as a utility. The theory is established with small classical structures.

  13. Inhalation exposure and risk of polycyclic aromatic hydrocarbons (PAHs) among the rural population adopting wood gasifier stoves compared to different fuel-stove users

    NASA Astrophysics Data System (ADS)

    Lin, Nan; Chen, Yuanchen; Du, Wei; Shen, Guofeng; Zhu, Xi; Huang, Tianbo; Wang, Xilong; Cheng, Hefa; Liu, Junfeng; Xue, Chunyu; Liu, Guangqing; Zeng, Eddy Y.; Xing, Baoshan; Tao, Shu

    2016-12-01

    Polycyclic aromatica hydrocarbons (PAHs) are a group of compounds with carcinogenic potentials and residential solid fuel combustion is one major source of PAHs in most developing countries. Replacement of traditional stoves with improved ones is believed to be a practical approach to reduce pollutant emissions, however, field assessments on the performance and consequent impacts on air quality and human health after adopting improved stoves are rare. The study is the first time to quantify inhalation exposure to PAHs among the residents who adopted wood gasifier stoves. The results were compared to those still burning coals in the region and compared to exposure levels for different fuel/stove users in literature. The results showed that the PAHs exposure levels for the wood gasifier stove users were significantly lower than the values for those using traditional wood stoves reported in literature, and the daily exposure concentrations of BaPeq (Benzo[a]pyrene equivalent concentration) can be reduced by 48%-91% if traditional wood stoves were replaced by wood gasifier stoves. The corresponding Incremental Lifetime Cancer Risk (ILCR) decreased approximately four times from 1.94 × 10-4 to 5.17 × 10-5. The average concentration of the total 26 PAHs for the wood users was 1091 ± 722 ng/m3, which was comparable to 1060 ± 927 ng/m3 for those using anthracite coals, but the composition profiles were considerably different. The average BaPeq were 116 and 25.8 ng/m3 for the wood and coal users, respectively, and the corresponding ILCR of the anthracite coal users was 1.69 × 10-5, which was nearly one third of those using the wood gasifier stoves. The wood users exposed to not only high levels of high molecular weight PAHs, but relatively high fractions of particulate phase PAHs in small particles compared to the coal users, resulting in high exposure risks.

  14. Caregiver talk to young Spanish-English bilinguals: comparing direct observation and parent-report measures of dual-language exposure.

    PubMed

    Marchman, Virginia A; Martínez, Lucía Z; Hurtado, Nereyda; Grüter, Theres; Fernald, Anne

    2017-01-01

    In research on language development by bilingual children, the early language environment is commonly characterized in terms of the relative amount of exposure a child gets to each language based on parent report. Little is known about how absolute measures of child-directed speech in two languages relate to language growth. In this study of 3-year-old Spanish-English bilinguals (n = 18), traditional parent-report estimates of exposure were compared to measures of the number of Spanish and English words children heard during naturalistic audio recordings. While the two estimates were moderately correlated, observed numbers of child-directed words were more consistently predictive of children's processing speed and standardized test performance, even when controlling for reported proportion of exposure. These findings highlight the importance of caregiver engagement in bilingual children's language outcomes in both of the languages they are learning.

  15. Comparative chemical analysis of dew and rain water

    NASA Astrophysics Data System (ADS)

    Lekouch, Imad; Mileta, Marina; Muselli, Marc; Milimouk-Melnytchouk, Irène; Šojat, Višnja; Kabbachi, Belkacem; Beysens, Daniel

    2010-02-01

    Dew and rain water were collected and analyzed during 3 years (2004-2006) in Zadar, Croatia. The goal was to characterize the chemical properties of dew water versus rain water (and the atmosphere in which they form) and to determine the extent to which they can be used as potable water. The corresponding parameters were measured: pH, electrical conductivity (EC), major anions (HCO 3-, Cl -, SO 42-, NO 3-), and major cations (NH 4+, Na +, K +, Ca 2+, Mg 2+). The mean pH and EC values were comparable for both dew and rain water, pH = 6.7 (dew) and pH = 6.35 (rain), EC = 195 µS cm - 1 (dew) and EC = 178 µS cm - 1 (rain). The ratio (SO 42- + NO 3-)/(Ca 2+ + Mg 2+) was lower than 1, indicating the alkaline nature of both dew and rain water. Both dew and rain water exhibited low mineralization. The analysis of the major ions showed that the concentration of cations is high compared to that of anions (presumably because the NO 2-, HCOO - and CH 3COO - ions were not measured), with Ca² +, Na + and Mg 2+ as the main ions. In order to discriminate between the marine and non-marine origin of ions, the sea-salt fraction (SSF) was calculated by taking Na + as a reference. The small SSF value in dew suggests a considerable contribution of non-marine origin for components Ca ²+, K +, SO 42- and NO 3-, except Cl -. In contrast, in rain water, the values of the non sea-salt fraction (NSSF) indicate that only Ca² + and NO 3- are not influenced by sea proximity. The study of the neutralization factor, NF, reveals the descending order of the cations in dew and rain water, NF Ca²+ > NF Mg²+ > NF K+ > NF NH4+. The dew and rain water are in conformity with the World Health Organization directives for potability, except for Mg 2+.

  16. A comparative study of human exposures to household air pollution from commonly used cookstoves in Sri Lanka.

    PubMed

    Chartier, R; Phillips, M; Mosquin, P; Elledge, M; Bronstein, K; Nandasena, S; Thornburg, V; Thornburg, J; Rodes, C

    2017-01-01

    Solid fuel burning cookstoves are a major source of household air pollution (HAP) and a significant environmental health risk in Sri Lanka. We report results of the first field study in Sri Lanka to include direct measurements of both real-time indoor concentrations and personal exposures of fine particulate matter (PM2.5 ) in households using the two most common stove types in Sri Lanka. A purposive sample of 53 households was selected in the rural community of Kopiwatta in central Sri Lanka, roughly balanced for stove type (traditional or improved 'Anagi') and ventilation (chimney present or absent). At each household, 48-h continuous real-time measurements of indoor kitchen PM2.5 and personal (primary cook) PM2.5 concentrations were measured using the RTI MicroPEM(™) personal exposure monitor. Questionnaires were used to collect data related to household demographics, characteristics, and self-reported health symptoms. All primary cooks were female and of an average age of 47 years, with 66% having completed primary education. Median income was slightly over half the national median monthly income. Use of Anagi stoves was positively associated with a higher education level of the primary cook (P = 0.026), although not associated with household income (P = 0.18). The MicroPEM monitors were well-received by participants, and this study's valid data capture rate exceeded 97%. Participant wearing compliance during waking hours was on average 87.2% on Day 1 and 83.3% on Day 2. Periods of non-compliance occurred solely during non-cooking times. The measured median 48-h average indoor PM2.5 concentration for households with Anagi stoves was 64 μg/m(3) if a chimney was present and 181 μg/m(3) if not. For households using traditional stoves, these values were 70 μg/m(3) if a chimney was present and 371 μg/m(3) if not. Overall, measured indoor PM2.5 concentrations ranged from a minimum of 33 μg/m(3) to a maximum of 940 μg/m(3) , while personal exposure

  17. A Comparative Analysis of Mitochondrial Genomes in Eustigmatophyte Algae

    PubMed Central

    Ševčíková, Tereza; Klimeš, Vladimír; Zbránková, Veronika; Strnad, Hynek; Hroudová, Miluše; Vlček, Čestmír; Eliáš, Marek

    2016-01-01

    Eustigmatophyceae (Ochrophyta, Stramenopiles) is a small algal group with species of the genus Nannochloropsis being its best studied representatives. Nuclear and organellar genomes have been recently sequenced for several Nannochloropsis spp., but phylogenetically wider genomic studies are missing for eustigmatophytes. We sequenced mitochondrial genomes (mitogenomes) of three species representing most major eustigmatophyte lineages, Monodopsis sp. MarTras21, Vischeria sp. CAUP Q 202 and Trachydiscus minutus, and carried out their comparative analysis in the context of available data from Nannochloropsis and other stramenopiles, revealing a number of noticeable findings. First, mitogenomes of most eustigmatophytes are highly collinear and similar in the gene content, but extensive rearrangements and loss of three otherwise ubiquitous genes happened in the Vischeria lineage; this correlates with an accelerated evolution of mitochondrial gene sequences in this lineage. Second, eustigmatophytes appear to be the only ochrophyte group with the Atp1 protein encoded by the mitogenome. Third, eustigmatophyte mitogenomes uniquely share a truncated nad11 gene encoding only the C-terminal part of the Nad11 protein, while the N-terminal part is encoded by a separate gene in the nuclear genome. Fourth, UGA as a termination codon and the cognate release factor mRF2 were lost from mitochondria independently by the Nannochloropsis and T. minutus lineages. Finally, the rps3 gene in the mitogenome of Vischeria sp. is interrupted by the UAG codon, but the genome includes a gene for an unusual tRNA with an extended anticodon loop that we speculate may serve as a suppressor tRNA to properly decode the rps3 gene. PMID:26872774

  18. Hidden Markov models for evolution and comparative genomics analysis.

    PubMed

    Bykova, Nadezda A; Favorov, Alexander V; Mironov, Andrey A

    2013-01-01

    The problem of reconstruction of ancestral states given a phylogeny and data from extant species arises in a wide range of biological studies. The continuous-time Markov model for the discrete states evolution is generally used for the reconstruction of ancestral states. We modify this model to account for a case when the states of the extant species are uncertain. This situation appears, for example, if the states for extant species are predicted by some program and thus are known only with some level of reliability; it is common for bioinformatics field. The main idea is formulation of the problem as a hidden Markov model on a tree (tree HMM, tHMM), where the basic continuous-time Markov model is expanded with the introduction of emission probabilities of observed data (e.g. prediction scores) for each underlying discrete state. Our tHMM decoding algorithm allows us to predict states at the ancestral nodes as well as to refine states at the leaves on the basis of quantitative comparative genomics. The test on the simulated data shows that the tHMM approach applied to the continuous variable reflecting the probabilities of the states (i.e. prediction score) appears to be more accurate then the reconstruction from the discrete states assignment defined by the best score threshold. We provide examples of applying our model to the evolutionary analysis of N-terminal signal peptides and transcription factor binding sites in bacteria. The program is freely available at http://bioinf.fbb.msu.ru/~nadya/tHMM and via web-service at http://bioinf.fbb.msu.ru/treehmmweb.

  19. Neuropeptidomics in Triatoma infestans. Comparative transcriptomic analysis among triatomines.

    PubMed

    Traverso, Lucila; Sierra, Ivana; Sterkel, Marcos; Francini, Flavio; Ons, Sheila

    2016-12-18

    Chagas' disease, affecting up to 6-7 million people worldwide, is transmitted to humans through the feces of triatomine kissing bugs. From these, Rhodnius prolixus, Triatoma dimidiata, Triatoma infestans and Triatoma pallidipennis are important vectors distributed throughout the Latin American subcontinent. Resistance to pyrethroids has been developed by some triatomine populations, especially T. infestans, obstructing their control. Given their role in the regulation of physiological processes, neuroendocrine-derived factors have been proposed as a source of molecular targets for new-generation insecticides. However, the involvement of neuropeptides in insecticide metabolism and resistance in insects has been poorly studied. In the present work, the sequences of 20 neuropeptide precursor genes in T. infestans, 16 in T. dimidiata, and 13 in T. pallidipennis detected in transcriptomic databases are reported, and a comparative analysis in triatomines is presented. A total of 59 neuropeptides were validated by liquid chromatography-tandem mass spectrometry in brain and nervous ganglia from T. infestans, revealing the existence of differential post-translational modifications, extended and truncated forms. The results suggest a high sequence conservation in some neuropeptide systems in triatomines, whereas remarkable differences occur in several others within the core domains. Comparisons of the basal expression levels for several neuropeptide precursor genes between pyrethroid sensitive and resistant population of T. infestans are also presented here, in order to introduce a proof of concept to test the involvement of neuropeptides in insecticide resistance. From the precursors tested, NVP and ITG peptides are significantly higher expressed in the resistant population. To our knowledge, this is the first report to associate differential neuropeptide expression with insecticide resistance. The information provided here contributes to creating conditions to widely

  20. Comparative genomic analysis of Chlamydia trachomatis oculotropic and genitotropic strains.

    PubMed

    Carlson, John H; Porcella, Stephen F; McClarty, Grant; Caldwell, Harlan D

    2005-10-01

    Chlamydia trachomatis infection is an important cause of preventable blindness and sexually transmitted disease (STD) in humans. C. trachomatis exists as multiple serovariants that exhibit distinct organotropism for the eye or urogenital tract. We previously reported tissue-tropic correlations with the presence or absence of a functional tryptophan synthase and a putative GTPase-inactivating domain of the chlamydial toxin gene. This suggested that these genes may be the primary factors responsible for chlamydial disease organotropism. To test this hypothesis, the genome of an oculotropic trachoma isolate (A/HAR-13) was sequenced and compared to the genome of a genitotropic (D/UW-3) isolate. Remarkably, the genomes share 99.6% identity, supporting the conclusion that a functional tryptophan synthase enzyme and toxin might be the principal virulence factors underlying disease organotropism. Tarp (translocated actin-recruiting phosphoprotein) was identified to have variable numbers of repeat units within the N and C portions of the protein. A correlation exists between lymphogranuloma venereum serovars and the number of N-terminal repeats. Single-nucleotide polymorphism (SNP) analysis between the two genomes highlighted the minimal genetic variation. A disproportionate number of SNPs were observed within some members of the polymorphic membrane protein (pmp) autotransporter gene family that corresponded to predicted T-cell epitopes that bind HLA class I and II alleles. These results implicate Pmps as novel immune targets, which could advance future chlamydial vaccine strategies. Lastly, a novel target for PCR diagnostics was discovered that can discriminate between ocular and genital strains. This discovery will enhance epidemiological investigations in nations where both trachoma and chlamydial STD are endemic.

  1. Comparative Analysis of Morphometric Characteristics of Scorpaenidae and Gobioninae

    PubMed Central

    Park, In-Seok; Gil, Hyun Woo; Oh, Ji Su; Choi, Hui Jung; Kim, Chi Hong

    2015-01-01

    Measurements of closely related sets of classical and truss dimensions were analyzed to discriminate species of scorpaenidae including the dark banded rockfish, Sebastes inermis, the black rockfish, S. schlegeli, and gobioninae including the striped shiner, Pungtungia herzi, and the slender shiner, Pseudopungtungia tenuicorpa. The measurements of the dimensions were arc sin square root transformed, and compared as a function of the standard length of each species for statistical analysis. For values of the classical dimensions of the rockfish, 6 were greater for the dark banded rockfish than for the black rockfish, 1 value was smaller for the former, and for 2 values there was no statistically significant difference (P > 0.05). For values of the classical dimensions of the shiners, 9 values were greater for the striped shiner than for the slender shiner, 2 values were smaller for the former, and for 1 value there was no statistically significant difference (P > 0.01). For values of the truss dimensions of the rockfish, 6 were greater for the dark banded rockfish than for the black rockfish, 1 was smaller for the former, and for 4 values there was no statistically significant difference (P > 0.05). For values of the truss dimensions of the shiners, 13 values were greater for the striped shiner than for the slender shiner, 3 values were smaller for the former, and for 6 values there was no statistically significant difference (P > 0.01). The dimension sets used in this study may be useful as taxonomic indicators for discriminating among fish species in Korea. PMID:27004265