Sample records for inverse factor analysis

  1. Intrinsic Risk Factors of Lateral Ankle Sprain: A Systematic Review and Meta-analysis.

    PubMed

    Kobayashi, Takumi; Tanaka, Masashi; Shida, Masahiro

    2016-01-01

    Lateral ankle ligamentous sprain (LAS) is one of the most common injuries in recreational activities and competitive sports. Many studies have attempted to determine whether there are certain intrinsic factors that can predict LAS. However, no consensus has been reached on the predictive intrinsic factors. To identify the intrinsic risk factors of LAS by meta-analysis from data in randomized control trials and prospective cohort studies. A systematic computerized literature search of MEDLINE, CINAHL, ScienceDirect, SPORTDiscus, and Cochrane Register of Clinical Trials was performed. A computerized literature search from inception to January 2015 resulted in 1133 studies of the LAS intrinsic risk factors written in English. Systematic review. Level 4. The modified quality index was used to assess the quality of the design of the papers and the standardized mean difference was used as an index to pool included study outcomes. Eight articles were included in this systematic review. Meta-analysis results showed that body mass index, slow eccentric inversion strength, fast concentric plantar flexion strength, passive inversion joint position sense, and peroneus brevis reaction time correlated with LAS. Body mass index, slow eccentric inversion strength, fast concentric plantar flexion strength, passive inversion joint position sense, and the reaction time of the peroneus brevis were associated with significantly increased risk of LAS.

  2. [Detection of factor VIII intron 1 inversion in severe haemophilia A].

    PubMed

    Liang, Yan; Yan, Zhen-yu; Yan, Mei; Hua, Bao-lai; Xiao, Bai; Zhao, Yong-qiang; Liu, Jing-zhong

    2009-06-01

    Screening the intron 1 inversion of factor VIII (FVIII) in the population of severe haemophilia A(HA) in China and performing carrier detection and prenatal diagnosis. Using LD-PCR to detect intron 22 inversions and multiple-PCR within two tubes to intron 1 inversions in severe HA patients. Carrier detection and prenatal diagnosis were performed in affected families. Linkage analysis and DNA sequencing were used to verify these tests. One hundred and eighteen patients were seven diagnosed as intron 22 inversions and 7 were intron 1 inversions out of 247 severe HA patients. The prevalence of the intron 1 inversion in Chinese severe haemophilia A patients was 2.8% (7/247). Six women from family A and 2 from family B were diagnosed as carriers. One fetus from family A was affected fetus. Intron 1 inversion could be detected directly by multiple-PCR within two tubes. This method made the strategy more perfective in carrier and prenatal diagnosis of haemophilia A.

  3. Selecting an Informative/Discriminating Multivariate Response for Inverse Prediction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thomas, Edward V.; Lewis, John. R.; Anderson-Cook, Christine Michaela

    The inverse prediction is important in a variety of scientific and engineering applications, such as to predict properties/characteristics of an object by using multiple measurements obtained from it. Inverse prediction can be accomplished by inverting parameterized forward models that relate the measurements (responses) to the properties/characteristics of interest. Sometimes forward models are computational/science based; but often, forward models are empirically based response surface models, obtained by using the results of controlled experimentation. For empirical models, it is important that the experiments provide a sound basis to develop accurate forward models in terms of the properties/characteristics (factors). And while nature dictatesmore » the causal relationships between factors and responses, experimenters can control the complexity, accuracy, and precision of forward models constructed via selection of factors, factor levels, and the set of trials that are performed. Recognition of the uncertainty in the estimated forward models leads to an errors-in-variables approach for inverse prediction. The forward models (estimated by experiments or science based) can also be used to analyze how well candidate responses complement one another for inverse prediction over the range of the factor space of interest. Furthermore, one may find that some responses are complementary, redundant, or noninformative. Simple analysis and examples illustrate how an informative and discriminating subset of responses could be selected among candidates in cases where the number of responses that can be acquired during inverse prediction is limited by difficulty, expense, and/or availability of material.« less

  4. Selecting an Informative/Discriminating Multivariate Response for Inverse Prediction

    DOE PAGES

    Thomas, Edward V.; Lewis, John. R.; Anderson-Cook, Christine Michaela; ...

    2017-07-01

    The inverse prediction is important in a variety of scientific and engineering applications, such as to predict properties/characteristics of an object by using multiple measurements obtained from it. Inverse prediction can be accomplished by inverting parameterized forward models that relate the measurements (responses) to the properties/characteristics of interest. Sometimes forward models are computational/science based; but often, forward models are empirically based response surface models, obtained by using the results of controlled experimentation. For empirical models, it is important that the experiments provide a sound basis to develop accurate forward models in terms of the properties/characteristics (factors). And while nature dictatesmore » the causal relationships between factors and responses, experimenters can control the complexity, accuracy, and precision of forward models constructed via selection of factors, factor levels, and the set of trials that are performed. Recognition of the uncertainty in the estimated forward models leads to an errors-in-variables approach for inverse prediction. The forward models (estimated by experiments or science based) can also be used to analyze how well candidate responses complement one another for inverse prediction over the range of the factor space of interest. Furthermore, one may find that some responses are complementary, redundant, or noninformative. Simple analysis and examples illustrate how an informative and discriminating subset of responses could be selected among candidates in cases where the number of responses that can be acquired during inverse prediction is limited by difficulty, expense, and/or availability of material.« less

  5. Spatial patterning in PM2.5 constituents under an inversion-focused sampling design across an urban area of complex terrain

    PubMed Central

    Tunno, Brett J; Dalton, Rebecca; Michanowicz, Drew R; Shmool, Jessie L C; Kinnee, Ellen; Tripathy, Sheila; Cambal, Leah; Clougherty, Jane E

    2016-01-01

    Health effects of fine particulate matter (PM2.5) vary by chemical composition, and composition can help to identify key PM2.5 sources across urban areas. Further, this intra-urban spatial variation in concentrations and composition may vary with meteorological conditions (e.g., mixing height). Accordingly, we hypothesized that spatial sampling during atmospheric inversions would help to better identify localized source effects, and reveal more distinct spatial patterns in key constituents. We designed a 2-year monitoring campaign to capture fine-scale intra-urban variability in PM2.5 composition across Pittsburgh, PA, and compared both spatial patterns and source effects during “frequent inversion” hours vs 24-h weeklong averages. Using spatially distributed programmable monitors, and a geographic information systems (GIS)-based design, we collected PM2.5 samples across 37 sampling locations per year to capture variation in local pollution sources (e.g., proximity to industry, traffic density) and terrain (e.g., elevation). We used inductively coupled plasma mass spectrometry (ICP-MS) to determine elemental composition, and unconstrained factor analysis to identify source suites by sampling scheme and season. We examined spatial patterning in source factors using land use regression (LUR), wherein GIS-based source indicators served to corroborate factor interpretations. Under both summer sampling regimes, and for winter inversion-focused sampling, we identified six source factors, characterized by tracers associated with brake and tire wear, steel-making, soil and road dust, coal, diesel exhaust, and vehicular emissions. For winter 24-h samples, four factors suggested traffic/fuel oil, traffic emissions, coal/industry, and steel-making sources. In LURs, as hypothesized, GIS-based source terms better explained spatial variability in inversion-focused samples, including a greater contribution from roadway, steel, and coal-related sources. Factor analysis produced source-related constituent suites under both sampling designs, though factors were more distinct under inversion-focused sampling. PMID:26507005

  6. The Chapel Hill hemophilia A dog colony exhibits a factor VIII gene inversion

    PubMed Central

    Lozier, Jay N.; Dutra, Amalia; Pak, Evgenia; Zhou, Nan; Zheng, Zhili; Nichols, Timothy C.; Bellinger, Dwight A.; Read, Marjorie; Morgan, Richard A.

    2002-01-01

    In the Chapel Hill colony of factor VIII-deficient dogs, abnormal sequence (ch8, for canine hemophilia 8, GenBank no. AF361485) follows exons 1–22 in the factor VIII transcript in place of exons 23–26. The canine hemophilia 8 locus (ch8) sequence was found in a 140-kb normal dog genomic DNA bacterial artificial chromosome (BAC) clone that was completely outside the factor VIII gene, but not in BAC clones containing the factor VIII gene. The BAC clone that contained ch8 also contained a homologue of F8A (factor 8 associated) sequence, which participates in a common inversion that causes severe hemophilia A in humans. Fluorescence in situ hybridization analysis indicated that exons 1–26 normally proceed sequentially from telomere to centromere at Xq28, and ch8 is telomeric to the factor VIII gene. The appearance of an “upstream” genomic sequence element (ch8) at the end of the aberrant factor VIII transcript suggested that an inversion of genomic DNA replaced factor VIII exons 22–26 with ch8. The F8A sequence appeared also in overlapping normal BAC clones containing factor VIII sequence. We hypothesized that homologous recombination between copies of canine F8A inside and outside the factor VIII gene had occurred, as in human hemophilia A. High-resolution fluorescent in situ hybridization on hemophilia A dog DNA revealed a pattern consistent with this inversion mechanism. We also identified a HindIII restriction fragment length polymorphism of F8A fragments that distinguished hemophilia A, carrier, and normal dogs' DNA. The Chapel Hill hemophilia A dog colony therefore replicates the factor VIII gene inversion commonly seen in humans with severe hemophilia A. PMID:12242334

  7. Factor Analysis by Generalized Least Squares.

    ERIC Educational Resources Information Center

    Joreskog, Karl G.; Goldberger, Arthur S.

    Aitkin's generalized least squares (GLS) principle, with the inverse of the observed variance-covariance matrix as a weight matrix, is applied to estimate the factor analysis model in the exploratory (unrestricted) case. It is shown that the GLS estimates are scale free and asymptotically efficient. The estimates are computed by a rapidly…

  8. Study on the determination and chiral inversion of R-salbutamol in human plasma and urine by liquid chromatography-tandem mass spectrometry.

    PubMed

    Zhou, Ting; Zeng, Jing; Liu, Shan; Zhao, Ting; Wu, Jie; Lai, Wenshi; He, Mingzhi; Xu, Beining; Qu, Shanshan; Xu, Ling; Tan, Wen

    2015-10-01

    The chiral inversion has been a concerned issue during the research and development of a chiral drug. In this study, a sensitive chiral liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for determination of salbutamol enantiomers in human plasma and urine. The chiral inversion mechanism of R-salbutamol was fully investigated for the first time by studying the effects of physicochemical factors, including pH, temperature and time. A fitted model to predict the chiral inversion ratio of R-salbutamol was proposed using a Box-Behnken design. All the samples were separated on an Astec Chirobiotic T column and detected by a tandem mass spectrometer in multiple reaction monitoring mode. Lower limit of quantification of 0.100ng/mL was achieved under the optimized conditions. The method was fully validated and successfully applied to the clinical pharmacokinetic study of R-salbutamol in healthy volunteers. Chiral inversion of R-salbutamol to S-salbutamol has been detected in urine samples. The results indicated that pH and temperature were two dominant factors that caused the chiral inversion of R-salbutamol, which should be taken into consideration during the analysis of chiral drugs. The chiral inversion of R-salbutamol determined in this study was confirmed resulted from the gastric acid in stomach rather than caused by the analysis conditions. Moreover, the calculated results of the fitted model matched very well with the enantioselective pharmacokinetic study of R-salbutamol, and the individual difference of the chiral inversion ratio of R-salbutamol was related to the individual gastric environment. On the basis of the results, this study provides important and concrete information not only for the chiral analysis but also for the metabolism research of chiral drugs. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Inversion of gravity gradient tensor data: does it provide better resolution?

    NASA Astrophysics Data System (ADS)

    Paoletti, V.; Fedi, M.; Italiano, F.; Florio, G.; Ialongo, S.

    2016-04-01

    The gravity gradient tensor (GGT) has been increasingly used in practical applications, but the advantages and the disadvantages of the analysis of GGT components versus the analysis of the vertical component of the gravity field are still debated. We analyse the performance of joint inversion of GGT components versus separate inversion of the gravity field alone, or of one tensor component. We perform our analysis by inspection of the Picard Plot, a Singular Value Decomposition tool, and analyse both synthetic data and gradiometer measurements carried out at the Vredefort structure, South Africa. We show that the main factors controlling the reliability of the inversion are algebraic ambiguity (the difference between the number of unknowns and the number of available data points) and signal-to-noise ratio. Provided that algebraic ambiguity is kept low and the noise level is small enough so that a sufficient number of SVD components can be included in the regularized solution, we find that: (i) the choice of tensor components involved in the inversion is not crucial to the overall reliability of the reconstructions; (ii) GGT inversion can yield the same resolution as inversion with a denser distribution of gravity data points, but with the advantage of using fewer measurement stations.

  10. [Long distance-PCR for detection of factor VIII gene inversion in patients with severe hemophilia A].

    PubMed

    Ding, Pei-Fang; Sun, Wei-Sheng; Wang, Qin-You; Liu, De-Chun; Zhang, Xue-Qin; Teng, Bin; Shen, Fa-Kui

    2003-08-01

    The aim of current study was to detect intron 22 inversion of factor VIII gene in severe hemophilia A (HA) patients and screen the carriers of the gene inversion. Fifty-five cases of severe HA were involved and factor VIII gene inversion was detected and identified by long distance-PCR (LD-PCR) and 0.6% agarose gel electrophoresis. The 11 kb and 12 kb bands indicate the factor VIII gene inversion and non-inversion, respectively. Occurring of both 11 kb and 12 kb bands indicates a carrier of the inversion. The results showed that factor VIII gene inversion existed in 22 out of 55 cases, which accounted for about 40% of total detected patients. Five carriers of factor VIII gene inversion were diagnosed from the members in 15 families. In conclusion, LD-PCR assay is a simple, rapid and accurate method for detection of factor VIII gene inversion, and this approach is helpful in screening, carrier testing, and prenatal diagnosis of severe hemophilia A.

  11. Diet, blood pressure, and multicollinearity.

    PubMed

    Reed, D; McGee, D; Yano, K; Hankin, J

    1985-01-01

    Recent reports of an inverse association between dietary calcium intake and hypertension stimulated this analysis of the relationship of blood pressure to more than 20 dietary factors among a group of 8000 Japanese men in Hawaii. Reported intakes of potassium, calcium, protein, and milk were all inversely associated with blood pressure levels when examined one at a time while controlling for other risk factors. Alcohol intake was directly associated with blood pressure, and was treated as a confounding variable in the analysis. The association of potassium intake with blood pressure was relatively stronger than the associations for other nutrients, but the intake of potassium was so highly correlated with intakes of calcium, milk, and protein that it was not statistically possible to identify the independent association of potassium and blood pressure. Calcium intake was strongly correlated with milk and potassium intakes, and only calcium from dairy sources was associated with blood pressure. These data thus indicate that several dietary factors are inversely related to blood pressure levels independently of other risk factors such as age, body mass, and alcohol intake. The high degree of intercorrelation (multicollinearity) among these dietary factors, however, indicates that the independent role of any specific nutrient cannot be conclusively separated from the possible effects of other nutrients in this type of study.

  12. A pericentric inversion of chromosome X disrupting F8 and resulting in haemophilia A.

    PubMed

    Xin, Yu; Zhou, Jingyi; Ding, Qiulan; Chen, Changming; Wu, Xi; Wang, Xuefeng; Wang, Hongli; Jiang, Xiaofeng

    2017-08-01

    The frequency of X chromosome pericentric inversion is much less than that of autosome chromosome. We hereby characterise a pericentric inversion of X chromosome associated with severe factor VIII (FVIII) deficiency in a sporadic haemophilia A (HA) pedigree. PCR primer walking and genome walking strategies were adopted to identify the exact breakpoints of the inversion. Copy number variations (CNVs) of the F8 and the whole chromosomes were detected by AccuCopy and Affymetrix CytoScan High Definition (HD) assays, respectively. A karyotype analysis was performed by cytogenetic G banding technique. We identified a previously undescribed type of pericentric inversion of the X chromosome [inv(X)(p11.21q28)] in the proband with FVIII:C <1%. One breakpoint was located in the intron 7 of the F 8, which disrupted the transcription of the F8, and the other located in the upstream of the PFKFB1 of the X chromosome. The inversion segment was approximately 64.4% of the total chromosomal length. The karyotype analysis of the X chromosome confirmed the pericentric inversion of the X chromosome in the proband and his mother. A haplotype analysis traced the inversion to his maternal grandfather, who was not a somatic mosaic of the inversion. This finding indicated that the causative mutation may originate from his germ cells or a rare possibility of germ-cell mosaicism. The characterisation of pericentric inversion involving F8 extended the molecular mechanisms causing HA. The pericentric inversion rearrangement involves F8 by non-homologous end joining is responsible for pathogensis of severe HA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  13. Selecting an Informative/Discriminating Multivariate Response for Inverse Prediction

    DOE PAGES

    Thomas, Edward V.; Lewis, John R.; Anderson-Cook, Christine M.; ...

    2017-11-21

    nverse prediction is important in a wide variety of scientific and engineering contexts. One might use inverse prediction to predict fundamental properties/characteristics of an object using measurements obtained from it. This can be accomplished by “inverting” parameterized forward models that relate the measurements (responses) to the properties/characteristics of interest. Sometimes forward models are science based; but often, forward models are empirically based, using the results of experimentation. For empirically-based forward models, it is important that the experiments provide a sound basis to develop accurate forward models in terms of the properties/characteristics (factors). While nature dictates the causal relationship between factorsmore » and responses, experimenters can influence control of the type, accuracy, and precision of forward models that can be constructed via selection of factors, factor levels, and the set of trials that are performed. Whether the forward models are based on science, experiments or both, researchers can influence the ability to perform inverse prediction by selecting informative response variables. By using an errors-in-variables framework for inverse prediction, this paper shows via simple analysis and examples how the capability of a multivariate response (with respect to being informative and discriminating) can vary depending on how well the various responses complement one another over the range of the factor-space of interest. Insights derived from this analysis could be useful for selecting a set of response variables among candidates in cases where the number of response variables that can be acquired is limited by difficulty, expense, and/or availability of material.« less

  14. Selecting an Informative/Discriminating Multivariate Response for Inverse Prediction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thomas, Edward V.; Lewis, John R.; Anderson-Cook, Christine M.

    nverse prediction is important in a wide variety of scientific and engineering contexts. One might use inverse prediction to predict fundamental properties/characteristics of an object using measurements obtained from it. This can be accomplished by “inverting” parameterized forward models that relate the measurements (responses) to the properties/characteristics of interest. Sometimes forward models are science based; but often, forward models are empirically based, using the results of experimentation. For empirically-based forward models, it is important that the experiments provide a sound basis to develop accurate forward models in terms of the properties/characteristics (factors). While nature dictates the causal relationship between factorsmore » and responses, experimenters can influence control of the type, accuracy, and precision of forward models that can be constructed via selection of factors, factor levels, and the set of trials that are performed. Whether the forward models are based on science, experiments or both, researchers can influence the ability to perform inverse prediction by selecting informative response variables. By using an errors-in-variables framework for inverse prediction, this paper shows via simple analysis and examples how the capability of a multivariate response (with respect to being informative and discriminating) can vary depending on how well the various responses complement one another over the range of the factor-space of interest. Insights derived from this analysis could be useful for selecting a set of response variables among candidates in cases where the number of response variables that can be acquired is limited by difficulty, expense, and/or availability of material.« less

  15. Round-off errors in cutting plane algorithms based on the revised simplex procedure

    NASA Technical Reports Server (NTRS)

    Moore, J. E.

    1973-01-01

    This report statistically analyzes computational round-off errors associated with the cutting plane approach to solving linear integer programming problems. Cutting plane methods require that the inverse of a sequence of matrices be computed. The problem basically reduces to one of minimizing round-off errors in the sequence of inverses. Two procedures for minimizing this problem are presented, and their influence on error accumulation is statistically analyzed. One procedure employs a very small tolerance factor to round computed values to zero. The other procedure is a numerical analysis technique for reinverting or improving the approximate inverse of a matrix. The results indicated that round-off accumulation can be effectively minimized by employing a tolerance factor which reflects the number of significant digits carried for each calculation and by applying the reinversion procedure once to each computed inverse. If 18 significant digits plus an exponent are carried for each variable during computations, then a tolerance value of 0.1 x 10 to the minus 12th power is reasonable.

  16. Shape and size variation on the wing of Drosophila mediopunctata: influence of chromosome inversions and genotype-environment interaction.

    PubMed

    Hatadani, Luciane Mendes; Klaczko, Louis Bernard

    2008-07-01

    The second chromosome of Drosophila mediopunctata is highly polymorphic for inversions. Previous work reported a significant interaction between these inversions and collecting date on wing size, suggesting the presence of genotype-environment interaction. We performed experiments in the laboratory to test for the joint effects of temperature and chromosome inversions on size and shape of the wing in D. mediopunctata. Size was measured as the centroid size, and shape was analyzed using the generalized least squares Procrustes superimposition followed by discriminant analysis and canonical variates analysis of partial warps and uniform components scores. Our findings show that wing size and shape are influenced by temperature, sex, and karyotype. We also found evidence suggestive of an interaction between the effects of karyotype and temperature on wing shape, indicating the existence of genotype-environment interaction for this trait in D. mediopunctata. In addition, the association between wing size and chromosome inversions is in agreement with previous results indicating that these inversions might be accumulating alleles adapted to different temperatures. However, no significant interaction between temperature and karyotype for size was found--in spite of the significant presence of temperature-genotype (cross) interaction. We suggest that other ecological factors--such as larval crowding--or seasonal variation of genetic content within inversions may explain the previous results.

  17. Inverse Association between Fruit and Vegetable Intake and BMI even after Controlling for Demographic, Socioeconomic and Lifestyle Factors

    PubMed Central

    Heo, Moonseong; Kim, Ryung S.; Wylie-Rosett, Judith; Allison, David B.; Heymsfield, Steve B.; Faith, Myles S.

    2011-01-01

    Objective To estimate fruit and vegetable (FV) intake levels of US adult population and evaluate the association between FV intake and BMI status after controlling for confounding demographic, socioeconomic and lifestyle factors. We also sought to identify moderating factors. Methods We used 2007 Behavior Risk Factors Surveillance System (N > 400,000) data. FV intake was dichotomized as ≥5 servings (FV5+) versus <5 servings/day. BMI status was categorized as normal, overweight, and obese. Identification of moderators was performed by testing interactions between BMI status and other variables using bivariate analyses followed by multiple logistic regression analysis incorporating complex survey sampling design features. Results Only 24.6% of US adults consumed ≥5 servings per day and less than 4% consumed 9 or more servings. Overweight (% FV5+ = 23.9%) and obese (21.9%) groups consumed significantly less FV than the normal-weight (27.4%) group (p < 0.0001). This inverse association remained significant even after controlling for potential confounding factors. Multivariate analysis identified five significant moderators (p < 0.0001) after controlling for all evaluated variables: race, sex, smoking status, health coverage, and physical activity. Notably, physically inactive obese males tended to consume the least FV (% FV5+ = 14.7%). Conclusion Current US population FV intake level is below recommended levels. The inverse association between FV intake and obesity was significant and was moderated by demographic, socioeconomic status, and lifestyle factors. These factors should be considered when developing policies and interventions to increase FV intake. PMID:22248995

  18. Analysis of a boron-carbide-drum-controlled critical reactor experiment

    NASA Technical Reports Server (NTRS)

    Mayo, W. T.

    1972-01-01

    In order to validate methods and cross sections used in the neutronic design of compact fast-spectrum reactors for generating electric power in space, an analysis of a boron-carbide-drum-controlled critical reactor was made. For this reactor the transport analysis gave generally satisfactory results. The calculated multiplication factor for the most detailed calculation was only 0.7-percent Delta k too high. Calculated reactivity worth of the control drums was $11.61 compared to measurements of $11.58 by the inverse kinetics methods and $11.98 by the inverse counting method. Calculated radial and axial power distributions were in good agreement with experiment.

  19. Optimal parallel solution of sparse triangular systems

    NASA Technical Reports Server (NTRS)

    Alvarado, Fernando L.; Schreiber, Robert

    1990-01-01

    A method for the parallel solution of triangular sets of equations is described that is appropriate when there are many right-handed sides. By preprocessing, the method can reduce the number of parallel steps required to solve Lx = b compared to parallel forward or backsolve. Applications are to iterative solvers with triangular preconditioners, to structural analysis, or to power systems applications, where there may be many right-handed sides (not all available a priori). The inverse of L is represented as a product of sparse triangular factors. The problem is to find a factored representation of this inverse of L with the smallest number of factors (or partitions), subject to the requirement that no new nonzero elements be created in the formation of these inverse factors. A method from an earlier reference is shown to solve this problem. This method is improved upon by constructing a permutation of the rows and columns of L that preserves triangularity and allow for the best possible such partition. A number of practical examples and algorithmic details are presented. The parallelism attainable is illustrated by means of elimination trees and clique trees.

  20. Confounding by dietary patterns of the inverse association between alcohol consumption and type 2 diabetes risk.

    PubMed

    Imamura, Fumiaki; Lichtenstein, Alice H; Dallal, Gerard E; Meigs, James B; Jacques, Paul F

    2009-07-01

    The ability to interpret epidemiologic observations is limited because of potential residual confounding by correlated dietary components. Dietary pattern analyses by factor analysis or partial least squares may overcome the limitation. To examine confounding by dietary pattern as well as standard risk factors and selected nutrients, the authors modeled the longitudinal association between alcohol consumption and 7-year risk of type 2 diabetes mellitus in 2,879 healthy adults enrolled in the Framingham Offspring Study (1991-2001) by Cox proportional hazard models. After adjustment for standard risk factors, consumers of > or =9.0 drinks/week had a significantly lower risk of type 2 diabetes mellitus compared with abstainers (hazard ratio = 0.47, 95% confidence interval (CI): 0.27, 0.81). Adjustment for selected nutrients had little effect on the hazard ratio, whereas adjustment for dietary pattern variables by factor analysis significantly shifted the hazard ratio away from null (hazard ratio = 0.33, 95% CI: 0.17, 0.64) by 40.0% (95% CI: 16.8, 57.0; P = 0.002). Dietary pattern variables by partial least squares showed similar results. Therefore, the observed inverse association, consistent with past studies, was confounded by dietary patterns, and this confounding was not captured by individual nutrient adjustment. The data suggest that alcohol intake, not dietary patterns associated with alcohol intake, is responsible for the observed inverse association with type 2 diabetes mellitus risk.

  1. Husbandry Emissions Estimation: Fusion of Mobile Surface and Airborne Remote Sensing and Mobile Surface In Situ Measurements

    NASA Astrophysics Data System (ADS)

    Leifer, I.; Hall, J. L.; Melton, C.; Tratt, D. M.; Chang, C. S.; Buckland, K. N.; Frash, J.; Leen, J. B.; Van Damme, M.; Clarisse, L.

    2017-12-01

    Emissions of methane and ammonia from intensive animal husbandry are important drivers of climate and photochemical and aerosol pollution. Husbandry emission estimates are somewhat uncertain because of their dependence on practices, temperature, micro-climate, and other factors, leading to variations in emission factors up to an order-of-magnitude. Mobile in situ measurements are increasingly being applied to derive trace gas emissions by Gaussian plume inversion; however, inversion with incomplete information can lead to erroneous emissions and incorrect source location. Mobile in situ concentration and wind data and mobile remote sensing column data from the Chino Dairy Complex in the Los Angeles Basin were collected near simultaneously (within 1-10 s, depending on speed) while transecting plumes, approximately orthogonal to winds. This analysis included airborne remote sensing trace gas information. MISTIR collected vertical column FTIR data simultaneously with in situ concentration data acquired by the AMOG-Surveyor while both vehicles traveled in convoy. The column measurements are insensitive to the turbulence characterization needed in Gaussian plume inversion of concentration data and thus provide a flux reference for evaluating in situ data inversions. Four different approaches were used on inversions for a single dairy, and also for the aggregate dairy complex plume. Approaches were based on differing levels of "knowledge" used in the inversion from solely the in situ platform and a single gas to a combination of information from all platforms and multiple gases. Derived dairy complex fluxes differed significantly from those estimated by other studies of the Chino complex. Analysis of long term satellite data showed that this most likely results from seasonality effects, highlighting the pitfalls of applying annualized extensions of flux measurements to a single campaign instantiation.

  2. Functional Impact and Evolution of a Novel Human Polymorphic Inversion That Disrupts a Gene and Creates a Fusion Transcript

    PubMed Central

    Puig, Marta; Castellano, David; Pantano, Lorena; Giner-Delgado, Carla; Izquierdo, David; Gayà-Vidal, Magdalena; Lucas-Lledó, José Ignacio; Esko, Tõnu; Terao, Chikashi; Matsuda, Fumihiko; Cáceres, Mario

    2015-01-01

    Despite many years of study into inversions, very little is known about their functional consequences, especially in humans. A common hypothesis is that the selective value of inversions stems in part from their effects on nearby genes, although evidence of this in natural populations is almost nonexistent. Here we present a global analysis of a new 415-kb polymorphic inversion that is among the longest ones found in humans and is the first with clear position effects. This inversion is located in chromosome 19 and has been generated by non-homologous end joining between blocks of transposable elements with low identity. PCR genotyping in 541 individuals from eight different human populations allowed the detection of tag SNPs and inversion genotyping in multiple populations worldwide, showing that the inverted allele is mainly found in East Asia with an average frequency of 4.7%. Interestingly, one of the breakpoints disrupts the transcription factor gene ZNF257, causing a significant reduction in the total expression level of this gene in lymphoblastoid cell lines. RNA-Seq analysis of the effects of this expression change in standard homozygotes and inversion heterozygotes revealed distinct expression patterns that were validated by quantitative RT-PCR. Moreover, we have found a new fusion transcript that is generated exclusively from inverted chromosomes around one of the breakpoints. Finally, by the analysis of the associated nucleotide variation, we have estimated that the inversion was generated ~40,000–50,000 years ago and, while a neutral evolution cannot be ruled out, its current frequencies are more consistent with those expected for a deleterious variant, although no significant association with phenotypic traits has been found so far. PMID:26427027

  3. Functional Impact and Evolution of a Novel Human Polymorphic Inversion That Disrupts a Gene and Creates a Fusion Transcript.

    PubMed

    Puig, Marta; Castellano, David; Pantano, Lorena; Giner-Delgado, Carla; Izquierdo, David; Gayà-Vidal, Magdalena; Lucas-Lledó, José Ignacio; Esko, Tõnu; Terao, Chikashi; Matsuda, Fumihiko; Cáceres, Mario

    2015-10-01

    Despite many years of study into inversions, very little is known about their functional consequences, especially in humans. A common hypothesis is that the selective value of inversions stems in part from their effects on nearby genes, although evidence of this in natural populations is almost nonexistent. Here we present a global analysis of a new 415-kb polymorphic inversion that is among the longest ones found in humans and is the first with clear position effects. This inversion is located in chromosome 19 and has been generated by non-homologous end joining between blocks of transposable elements with low identity. PCR genotyping in 541 individuals from eight different human populations allowed the detection of tag SNPs and inversion genotyping in multiple populations worldwide, showing that the inverted allele is mainly found in East Asia with an average frequency of 4.7%. Interestingly, one of the breakpoints disrupts the transcription factor gene ZNF257, causing a significant reduction in the total expression level of this gene in lymphoblastoid cell lines. RNA-Seq analysis of the effects of this expression change in standard homozygotes and inversion heterozygotes revealed distinct expression patterns that were validated by quantitative RT-PCR. Moreover, we have found a new fusion transcript that is generated exclusively from inverted chromosomes around one of the breakpoints. Finally, by the analysis of the associated nucleotide variation, we have estimated that the inversion was generated ~40,000-50,000 years ago and, while a neutral evolution cannot be ruled out, its current frequencies are more consistent with those expected for a deleterious variant, although no significant association with phenotypic traits has been found so far.

  4. Inverse Modeling of Texas NOx Emissions Using Space-Based and Ground-Based NO2 Observations

    NASA Technical Reports Server (NTRS)

    Tang, Wei; Cohan, D.; Lamsal, L. N.; Xiao, X.; Zhou, W.

    2013-01-01

    Inverse modeling of nitrogen oxide (NOx) emissions using satellite-based NO2 observations has become more prevalent in recent years, but has rarely been applied to regulatory modeling at regional scales. In this study, OMI satellite observations of NO2 column densities are used to conduct inverse modeling of NOx emission inventories for two Texas State Implementation Plan (SIP) modeling episodes. Addition of lightning, aircraft, and soil NOx emissions to the regulatory inventory narrowed but did not close the gap between modeled and satellite observed NO2 over rural regions. Satellitebased top-down emission inventories are created with the regional Comprehensive Air Quality Model with extensions (CAMx) using two techniques: the direct scaling method and discrete Kalman filter (DKF) with Decoupled Direct Method (DDM) sensitivity analysis. The simulations with satellite-inverted inventories are compared to the modeling results using the a priori inventory as well as an inventory created by a ground-level NO2 based DKF inversion. The DKF inversions yield conflicting results: the satellite based inversion scales up the a priori NOx emissions in most regions by factors of 1.02 to 1.84, leading to 3-55% increase in modeled NO2 column densities and 1-7 ppb increase in ground 8 h ozone concentrations, while the ground-based inversion indicates the a priori NOx emissions should be scaled by factors of 0.34 to 0.57 in each region. However, none of the inversions improve the model performance in simulating aircraft-observed NO2 or ground-level ozone (O3) concentrations.

  5. Inverse modeling of Texas NOx emissions using space-based and ground-based NO2 observations

    NASA Astrophysics Data System (ADS)

    Tang, W.; Cohan, D. S.; Lamsal, L. N.; Xiao, X.; Zhou, W.

    2013-11-01

    Inverse modeling of nitrogen oxide (NOx) emissions using satellite-based NO2 observations has become more prevalent in recent years, but has rarely been applied to regulatory modeling at regional scales. In this study, OMI satellite observations of NO2 column densities are used to conduct inverse modeling of NOx emission inventories for two Texas State Implementation Plan (SIP) modeling episodes. Addition of lightning, aircraft, and soil NOx emissions to the regulatory inventory narrowed but did not close the gap between modeled and satellite-observed NO2 over rural regions. Satellite-based top-down emission inventories are created with the regional Comprehensive Air Quality Model with extensions (CAMx) using two techniques: the direct scaling method and discrete Kalman filter (DKF) with decoupled direct method (DDM) sensitivity analysis. The simulations with satellite-inverted inventories are compared to the modeling results using the a priori inventory as well as an inventory created by a ground-level NO2-based DKF inversion. The DKF inversions yield conflicting results: the satellite-based inversion scales up the a priori NOx emissions in most regions by factors of 1.02 to 1.84, leading to 3-55% increase in modeled NO2 column densities and 1-7 ppb increase in ground 8 h ozone concentrations, while the ground-based inversion indicates the a priori NOx emissions should be scaled by factors of 0.34 to 0.57 in each region. However, none of the inversions improve the model performance in simulating aircraft-observed NO2 or ground-level ozone (O3) concentrations.

  6. Inverse modeling of Texas NOx emissions using space-based and ground-based NO2 observations

    NASA Astrophysics Data System (ADS)

    Tang, W.; Cohan, D.; Lamsal, L. N.; Xiao, X.; Zhou, W.

    2013-07-01

    Inverse modeling of nitrogen oxide (NOx) emissions using satellite-based NO2 observations has become more prevalent in recent years, but has rarely been applied to regulatory modeling at regional scales. In this study, OMI satellite observations of NO2 column densities are used to conduct inverse modeling of NOx emission inventories for two Texas State Implementation Plan (SIP) modeling episodes. Addition of lightning, aircraft, and soil NOx emissions to the regulatory inventory narrowed but did not close the gap between modeled and satellite observed NO2 over rural regions. Satellite-based top-down emission inventories are created with the regional Comprehensive Air Quality Model with extensions (CAMx) using two techniques: the direct scaling method and discrete Kalman filter (DKF) with Decoupled Direct Method (DDM) sensitivity analysis. The simulations with satellite-inverted inventories are compared to the modeling results using the a priori inventory as well as an inventory created by a ground-level NO2 based DKF inversion. The DKF inversions yield conflicting results: the satellite-based inversion scales up the a priori NOx emissions in most regions by factors of 1.02 to 1.84, leading to 3-55% increase in modeled NO2 column densities and 1-7 ppb increase in ground 8 h ozone concentrations, while the ground-based inversion indicates the a priori NOx emissions should be scaled by factors of 0.34 to 0.57 in each region. However, none of the inversions improve the model performance in simulating aircraft-observed NO2 or ground-level ozone (O3) concentrations.

  7. Bayesian linearized amplitude-versus-frequency inversion for quality factor and its application

    NASA Astrophysics Data System (ADS)

    Yang, Xinchao; Teng, Long; Li, Jingnan; Cheng, Jiubing

    2018-06-01

    We propose a straightforward attenuation inversion method by utilizing the amplitude-versus-frequency (AVF) characteristics of seismic data. A new linearized approximation equation of the angle and frequency dependent reflectivity in viscoelastic media is derived. We then use the presented equation to implement the Bayesian linear AVF inversion. The inversion result includes not only P-wave and S-wave velocities, and densities, but also P-wave and S-wave quality factors. Synthetic tests show that the AVF inversion surpasses the AVA inversion for quality factor estimation. However, a higher signal noise ratio (SNR) of data is necessary for the AVF inversion. To show its feasibility, we apply both the new Bayesian AVF inversion and conventional AVA inversion to a tight gas reservoir data in Sichuan Basin in China. Considering the SNR of the field data, a combination of AVF inversion for attenuation parameters and AVA inversion for elastic parameters is recommended. The result reveals that attenuation estimations could serve as a useful complement in combination with the AVA inversion results for the detection of tight gas reservoirs.

  8. A 3D inversion for all-space magnetotelluric data with static shift correction

    NASA Astrophysics Data System (ADS)

    Zhang, Kun

    2017-04-01

    Base on the previous studies on the static shift correction and 3D inversion algorithms, we improve the NLCG 3D inversion method and propose a new static shift correction method which work in the inversion. The static shift correction method is based on the 3D theory and real data. The static shift can be detected by the quantitative analysis of apparent parameters (apparent resistivity and impedance phase) of MT in high frequency range, and completed correction with inversion. The method is an automatic processing technology of computer with 0 cost, and avoids the additional field work and indoor processing with good results. The 3D inversion algorithm is improved (Zhang et al., 2013) base on the NLCG method of Newman & Alumbaugh (2000) and Rodi & Mackie (2001). For the algorithm, we added the parallel structure, improved the computational efficiency, reduced the memory of computer and added the topographic and marine factors. So the 3D inversion could work in general PC with high efficiency and accuracy. And all the MT data of surface stations, seabed stations and underground stations can be used in the inversion algorithm.

  9. Inverse Association between Diabetes and Altitude: A Cross Sectional Study in the Adult Population of the United States

    PubMed Central

    Woolcott, Orison O.; Castillo, Oscar A.; Gutierrez, Cesar; Elashoff, Robert M.; Stefanovski, Darko; Bergman, Richard N.

    2014-01-01

    Objective To determine whether geographical elevation is inversely associated with diabetes, while adjusting for multiple risk factors. Design and Methods This is a cross-sectional analysis of publicly available online data from the Behavioral Risk Factor Surveillance System, 2009. Final dataset included 285,196 US adult subjects. Odds ratios were obtained from multilevel mixed-effects logistic regression analysis. Results Among US adults (≥20 years old), the odds ratio for diabetes were 1.00 between 0−499 m of altitude (reference), 0.95 (95% confidence interval, 0.90 to 1.01) between 500−1,499 m, and 0.88 (0.81 to 0.96) between 1,500−3,500 m, adjusting for age, sex, body mass index, ethnicity, self-reported fruit and vegetable consumption, self-reported physical activity, current smoking status, level of education, income, health status, employment status, and county-level information on migration rate, urbanization, and latitude. The inverse association between altitude and diabetes in the US was found among men [0.84 (0.76 to 0.94)], but not women [1.09 (0.97 to 1.22)]. Conclusions Among US adults, living at high altitude (1,500−3,500 m) is associated with lower odds of having diabetes than living between 0−499 m, while adjusting for multiple risk factors. Our findings suggest that geographical elevation may be an important factor linked to diabetes. PMID:24890677

  10. Parameter estimation of a nonlinear Burger's model using nanoindentation and finite element-based inverse analysis

    NASA Astrophysics Data System (ADS)

    Hamim, Salah Uddin Ahmed

    Nanoindentation involves probing a hard diamond tip into a material, where the load and the displacement experienced by the tip is recorded continuously. This load-displacement data is a direct function of material's innate stress-strain behavior. Thus, theoretically it is possible to extract mechanical properties of a material through nanoindentation. However, due to various nonlinearities associated with nanoindentation the process of interpreting load-displacement data into material properties is difficult. Although, simple elastic behavior can be characterized easily, a method to characterize complicated material behavior such as nonlinear viscoelasticity is still lacking. In this study, a nanoindentation-based material characterization technique is developed to characterize soft materials exhibiting nonlinear viscoelasticity. Nanoindentation experiment was modeled in finite element analysis software (ABAQUS), where a nonlinear viscoelastic behavior was incorporated using user-defined subroutine (UMAT). The model parameters were calibrated using a process called inverse analysis. In this study, a surrogate model-based approach was used for the inverse analysis. The different factors affecting the surrogate model performance are analyzed in order to optimize the performance with respect to the computational cost.

  11. Conflicting relationship between age-dependent disorders, valvular heart disease and coronary artery disease by covariance structure analysis: Possible contribution of natriuretic peptide.

    PubMed

    Fukumoto, Risa; Kawai, Makoto; Minai, Kosuke; Ogawa, Kazuo; Yoshida, Jun; Inoue, Yasunori; Morimoto, Satoshi; Tanaka, Toshikazu; Nagoshi, Tomohisa; Ogawa, Takayuki; Yoshimura, Michihiro

    2017-01-01

    It is conceivable that contemporary valvular heart disease (VHD) is affected largely by an age-dependent atherosclerotic process, which is similar to that observed in coronary artery disease (CAD). However, a comorbid condition of VHD and CAD has not been precisely examined. The first objective of this study was to examine a possible comorbid condition. Provided that there is no comorbidity, the second objective was to search for the possible reasons by using conventional risk factors and plasma B-type natriuretic peptide (BNP) because BNP has a potentiality to suppress atherosclerotic development. The study population consisted of 3,457 patients consecutively admitted to our institution. The possible comorbid condition of VHD and CAD and the factors that influence the comorbidity were examined by covariance structure analysis and multivariate analysis. The distribution of the patients with VHD and those with CAD in the histograms showed that the incidence of VHD and the severity of CAD rose with seniority in appearance. The real statistical analysis was planned by covariance structure analysis. The current path model revealed that aging was associated with VHD and CAD severity (P < 0.001 for each); however, as a notable result, there was an inverse association regarding the comorbid condition between VHD and CAD (Correlation coefficient [β]: -0.121, P < 0.001). As the second objective, to clarify the factors leading to this inverse association, the contribution of conventional risk factors, such as age, gender, hypertension, smoking, diabetes, obesity and dyslipidemia, to VHD and CAD were examined by multivariate analysis. However, these factors did not exert an opposing effect on VHD and CAD, and the inverse association defied explanation. Since different pathological mechanisms may contribute to the formation of VHD and CAD, a differentially proposed path model using plasma BNP revealed that an increase in plasma BNP being drawn by VHD suppressed the progression of CAD (β: -0.465, P < 0.001). The incidence of VHD and CAD showed a significant conflicting relationship. This result supported the likely presence of unknown diverse mechanisms on top of the common cascade of atherosclerosis. Among them, the continuous elevation of plasma BNP due to VHD might be one of the explicable factors suppressing the progression of CAD.

  12. Angle dependence in slow photon photocatalysis using TiO2 inverse opals

    NASA Astrophysics Data System (ADS)

    Curti, Mariano; Zvitco, Gonzalo; Grela, María Alejandra; Mendive, Cecilia B.

    2018-03-01

    The slow photon effect was studied by means of the photocatalytic degradation of stearic acid over TiO2 inverse opals. The comparison of the degradation rates over inverse opals with those obtained over disordered structures at different irradiation angles showed that the irradiation at the blue edge of the stopband leads to the activation of the effect, evidenced by an improvement factor of 1.8 ± 0.6 in the reaction rate for irradiation at 40°. The rigorous coupled-wave analysis (RCWA) method was employed to confirm the source of the enhancement; simulated spectra showed an enhancement in the absorption of the TiO2 matrix that composes the inverse opal at a 40° irradiation angle, owing to an appropriate position of the stopband in relation to the absorption onset of TiO2.

  13. Environmental Hygiene and Risk of Inflammatory Bowel Diseases: A Systematic Review and Meta-analysis.

    PubMed

    Cholapranee, Aurada; Ananthakrishnan, Ashwin N

    2016-09-01

    According to the hygiene hypothesis, individuals raised in a sanitary environment have a higher risk of developing inflammatory bowel diseases (IBD). However, results have been inconsistent. We conducted this systematic review of factors related to environmental hygiene and risk of IBD, Crohn's disease (CD) and ulcerative colitis (UC). A systematic search was performed on MEDLINE between 1980 and 2015 to identify studies of the association between IBD and contact with pets and farm animals, number of siblings, bedroom sharing in childhood, and access to personal toilet and hot water. Random- or fixed-effect meta-analyses were performed, and analysis further stratified based on ethnicity of the included cohort. A total of 29 relevant studies were included. Having a pet (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.63-0.88) and contact with farm animals was inversely associated with risk of IBD (OR, 0.45; 95% CI, 0.31-0.60). However, the strength of association with farm animals was statistically stronger in non-white cohorts (OR, 0.27; 95% CI, 0.02-0.53) than in white cohorts (OR, 0.55; 95% CI, 0.45-0.65) (P = 0.028). Access to toilet (OR, 0.71; 95% CI, 0.56-0.85) and hot water (OR, 0.67; 95% CI, 0.44-0.89) was inversely associated with UC in non-white populations but not whites. Having more than 2 siblings was inversely associated with risk of CD. Several factors pertaining to reduced environmental hygiene are inversely associated with risk of IBD. However, underlying ethnicity influences susceptibility to the effect of these factors.

  14. Male infertility associated with de novo pericentric inversion of chromosome 1.

    PubMed

    Balasar, Özgür; Zamani, Ayşe Gül; Balasar, Mehmet; Acar, Hasan

    2017-12-01

    Inversion occurs after two breaks in a chromosome have happened and the segment rotates 180° before reinserting. Inversion carriers have produced abnormal gametes if there is an odd number crossing- over between the inverted and the normal homologous chromosomes causing a duplication or deletion. Reproductive risks such as infertility, abortion, stillbirth and birth of malformed child would be expected in that case. A 54-year- old male patient was consulted to our clinic for primary infertility. The routine chromosome study were applied using peripheral blood lymphocyte cultures and analyzed by giemsa-trypsin-giemsa (GTG) banding, and centromer banding (C-banding) stains. Y chromosome microdeletions in the azoospermia factor (AZF) regions were analyzed with polymerase chain reaction. Additional test such as fluorescence in situ hybridization (FISH) was used to detect the sex-determining region of the Y chromosome (SRY). Semen analysis showed azoospermia. A large pericentric inversion of chromosome 1 46,XY, inv(1) (p22q32) was found in routine chromosome analysis. No microdeletions were seen in AZF regions. In our patient the presence of SRY region was observed by using FISH technique with SRY-specific probe. Men who have pericentric inversion of chromosome 1, appear to be at risk for infertility brought about by spermatogenic breakdown. The etiopathogenic relationship between azoospermia and pericentric inversion of chromosome 1 is discussed.

  15. Collective Socialization and Child Conduct Problems: A Multilevel Analysis with an African American Sample

    ERIC Educational Resources Information Center

    Simons, Leslie Gordon; Simons, Ronald L.; Conger, Rand D.; Brody, Gene H.

    2004-01-01

    This article uses hierarchical linear modeling with a sample of African American children and their primary caregivers to examine the association between various community factors and child conduct problems. The analysis revealed a rather strong inverse association between level of collective socialization and conduct problems. This relationship…

  16. The association between body mass index and severe biliary infections: a multivariate analysis.

    PubMed

    Stewart, Lygia; Griffiss, J McLeod; Jarvis, Gary A; Way, Lawrence W

    2012-11-01

    Obesity has been associated with worse infectious disease outcomes. It is a risk factor for cholesterol gallstones, but little is known about associations between body mass index (BMI) and biliary infections. We studied this using factors associated with biliary infections. A total of 427 patients with gallstones were studied. Gallstones, bile, and blood (as applicable) were cultured. Illness severity was classified as follows: none (no infection or inflammation), systemic inflammatory response syndrome (fever, leukocytosis), severe (abscess, cholangitis, empyema), or multi-organ dysfunction syndrome (bacteremia, hypotension, organ failure). Associations between BMI and biliary bacteria, bacteremia, gallstone type, and illness severity were examined using bivariate and multivariate analysis. BMI inversely correlated with pigment stones, biliary bacteria, bacteremia, and increased illness severity on bivariate and multivariate analysis. Obesity correlated with less severe biliary infections. BMI inversely correlated with pigment stones and biliary bacteria; multivariate analysis showed an independent correlation between lower BMI and illness severity. Most patients with severe biliary infections had a normal BMI, suggesting that obesity may be protective in biliary infections. This study examined the correlation between BMI and biliary infection severity. Published by Elsevier Inc.

  17. Determining OCT structure and COB Location of the Omani Gulf of Aden Continental Margin from Gravity Inversion, Residual Depth Anomaly and Subsidence Analysis.

    NASA Astrophysics Data System (ADS)

    Cowie, Leanne; Kusznir, Nick; Leroy, Sylvie; Manatshal, Gianreto

    2013-04-01

    Knowledge and understanding of the ocean-continent transition (OCT) structure and continent-ocean boundary (COB) location, the distribution of thinned continental crust and lithosphere, its distal extent and the start of unequivocal oceanic crust are of critical importance in evaluating rifted continental margin formation and evolution. In order to determine the OCT structure and COB location for the eastern Gulf of Aden, along the Oman margin, we use a combination of gravity inversion, subsidence analysis and residual depth anomaly (RDA) analysis. Gravity inversion has been used to determine Moho depth, crustal basement thickness and continental lithosphere thinning; subsidence analysis has been used to determine the distribution of continental lithosphere thinning; and RDAs have been used to investigate the OCT bathymetric anomalies with respect to expected oceanic bathymetries at rifted margins. The gravity inversion method, which is carried out in the 3D spectral domain, incorporates a lithosphere thermal gravity anomaly and includes a correction for volcanic addition due to decompression melting. Reference Moho depths used in the gravity inversion have been calibrated against seismic refraction Moho depths. RDAs have been calculated by comparing observed and age predicted oceanic bathymetries, using the thermal plate model predictions from Crosby and McKenzie (2009). RDAs have been computed along profiles and have been corrected for sediment loading using flexural back-stripping and decompaction. In addition, gravity inversion crustal basement thicknesses together with Airy isostasy have been used to predict a synthetic RDA. The RDA results show a change in RDA signature and may be used to estimate the distal extent of thinned continental crust and where oceanic crust begins. Continental lithosphere thinning has been determined using flexural back-stripping and subsidence analysis assuming the classical rift model of McKenzie (1978) with a correction for volcanic addition due to decompression melting based on White & McKenzie (1989). Gravity inversion and the "synthetic" gravity derived RDA both show generally normal thickness oceanic crust, with some localised thin oceanic crust. Continental lithosphere thinning factors determined from gravity inversion and subsidence analysis are in good agreement and have been used to constrain COB location along the profile lines. These techniques show that the OCT in the eastern Gulf of Aden, is relatively narrow, with the distance between the COB and the margin hinge measuring less than 100km.

  18. Aging and low back pain among exercise participants: a follow-up study with psychological adaptation factors.

    PubMed

    Wilks, Scott E; Kadivar, Zahra; Guillory, Stephen A; Isaza, Jorge

    2009-01-01

    This study is a follow-up to a study previously published in this journal that reported the moderating function of exercise exertion amid the relationship between age and low back pain (LBP) among consistent exercise participants. The current study analyzed factors of psychological adaptation as potential mediators within the age--LBP relationship. Measures of psychological adaptation included psychological vulnerability, avoidant coping, resilient coping, and perceived resilience. The sample reported slightly moderate psychological vulnerability; a moderate extent of avoidant coping and resilient coping; and high resilience. Age inversely correlated with psychological vulnerability and avoidance coping. LBP correlated inversely with avoidant coping. Avoidant coping positively mediated (enhanced) age's effect on LBP. Results from this follow-up analysis highlight the importance of understanding and testing psychological factors in models with age and a physical health outcome.

  19. Physical activity and selected cardiovascular risk factors in middle-aged male personnel of self-defense forces.

    PubMed

    Sakuta, Hidenari; Suzuki, Takashi

    2006-01-01

    We cross-sectionally analyzed the association between duration of physical activity and the presence of selected cardiovascular risk factors in the middle-aged male personnel of the Self-Defense Forces who underwent retirement check-up (n = 974). In a univariate regression analysis, duration of high intensity physical activity but not that of moderate or low intensity physical activity inversely correlated with body mass index (BMI), triglyceride, fasting plasma glucose, white blood cell (WBC) count and systolic blood pressure. No intensity categories of physical activity correlated with total cholesterol. In a multivariate logistic regression analysis adjusted for lifestyle factors and the rank, the odds ratio per 1 h/wk increase in high intensity physical activity was .88 (95% confidence interval (CI) .80-.97; P=.007) for the presence of obesity (BMI 25.0 kg/m2), .88 (95% CI .81-.95; P = .002) for hypertrigly ceridemia, .87 (95% CI .76-.99; P=.034) for type 2 diabetes, and .90 (95% CI .82-.99; P=.037) for hypertension. Neither hypercholesterolemia nor high WBC count (> or = 6,900/microl) was associated with high intensity physical activity. High intensity physical activity inversely correlated with traditional cardiovascular risk factors in the middle-aged men.

  20. Recursive inverse factorization.

    PubMed

    Rubensson, Emanuel H; Bock, Nicolas; Holmström, Erik; Niklasson, Anders M N

    2008-03-14

    A recursive algorithm for the inverse factorization S(-1)=ZZ(*) of Hermitian positive definite matrices S is proposed. The inverse factorization is based on iterative refinement [A.M.N. Niklasson, Phys. Rev. B 70, 193102 (2004)] combined with a recursive decomposition of S. As the computational kernel is matrix-matrix multiplication, the algorithm can be parallelized and the computational effort increases linearly with system size for systems with sufficiently sparse matrices. Recent advances in network theory are used to find appropriate recursive decompositions. We show that optimization of the so-called network modularity results in an improved partitioning compared to other approaches. In particular, when the recursive inverse factorization is applied to overlap matrices of irregularly structured three-dimensional molecules.

  1. An Adaptive Model of Student Performance Using Inverse Bayes

    ERIC Educational Resources Information Center

    Lang, Charles

    2014-01-01

    This article proposes a coherent framework for the use of Inverse Bayesian estimation to summarize and make predictions about student behaviour in adaptive educational settings. The Inverse Bayes Filter utilizes Bayes theorem to estimate the relative impact of contextual factors and internal student factors on student performance using time series…

  2. Spatial operator factorization and inversion of the manipulator mass matrix

    NASA Technical Reports Server (NTRS)

    Rodriguez, Guillermo; Kreutz-Delgado, Kenneth

    1992-01-01

    This paper advances two linear operator factorizations of the manipulator mass matrix. Embedded in the factorizations are many of the techniques that are regarded as very efficient computational solutions to inverse and forward dynamics problems. The operator factorizations provide a high-level architectural understanding of the mass matrix and its inverse, which is not visible in the detailed algorithms. They also lead to a new approach to the development of computer programs or organize complexity in robot dynamics.

  3. Correlations between brain structure and symptom dimensions of psychosis in schizophrenia, schizoaffective, and psychotic bipolar I disorders.

    PubMed

    Padmanabhan, Jaya L; Tandon, Neeraj; Haller, Chiara S; Mathew, Ian T; Eack, Shaun M; Clementz, Brett A; Pearlson, Godfrey D; Sweeney, John A; Tamminga, Carol A; Keshavan, Matcheri S

    2015-01-01

    Structural alterations may correlate with symptom severity in psychotic disorders, but the existing literature on this issue is heterogeneous. In addition, it is not known how cortical thickness and cortical surface area correlate with symptom dimensions of psychosis. Subjects included 455 individuals with schizophrenia, schizoaffective, or bipolar I disorders. Data were obtained as part of the Bipolar Schizophrenia Network for Intermediate Phenotypes study. Diagnosis was made through the Structured Clinical Interview for DSM-IV. Positive and negative symptom subscales were assessed using the Positive and Negative Syndrome Scale. Structural brain measurements were extracted from T1-weight structural MRIs using FreeSurfer v5.1 and were correlated with symptom subscales using partial correlations. Exploratory factor analysis was also used to identify factors among those regions correlating with symptom subscales. The positive symptom subscale correlated inversely with gray matter volume (GMV) and cortical thickness in frontal and temporal regions, whereas the negative symptom subscale correlated inversely with right frontal cortical surface area. Among regions correlating with the positive subscale, factor analysis identified four factors, including a temporal cortical thickness factor and frontal GMV factor. Among regions correlating with the negative subscale, factor analysis identified a frontal GMV-cortical surface area factor. There was no significant diagnosis by structure interactions with symptom severity. Structural measures correlate with positive and negative symptom severity in psychotic disorders. Cortical thickness demonstrated more associations with psychopathology than cortical surface area. © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  4. Thinning Factors and Crustal Thicknesses at the Propagating Tip of Sea-floor Spreading in the Woodlark Basin

    NASA Astrophysics Data System (ADS)

    Gozzard, S. P.; Kusznir, N.; Goodliffe, A.; Manatschal, G.

    2007-12-01

    Understanding how the continental crust and lithosphere thins at the propagating tip of sea-floor spreading is the key to understanding the continental breakup process. The Woodlark Basin, a young ocean basin located in the Western Pacific to the east of Papua New Guinea, commenced formation at approximately 8.4Ma and is propagating westwards at a rate of approximately 140km/Myr. Immediately to the west of the most recent segment of sea-floor spreading propagation, in the vicinity of the Moresby Seamount, evidence from bathymetry, subsidence and seismic Moho depth suggests that continental lithosphere is being thinned. In this study we have determined lithosphere thinning in the vicinity of the Moresby Seamount at the level of the whole lithosphere, the whole crust and the upper crust. Whole lithosphere thinning factors have been determined from subsidence analysis; whole continental crustal thinning factors have been determined from gravity inversions and upper crustal thinning factors have been determined from fault analysis. Three 2D seismic profiles surrounding the Moresby Seamount have been flexurally backstripped to the base of the syn-rift sediments to determine the water loaded subsidence. Using the McKenzie lithosphere extension model, modified to include volcanic addition at high thinning factors, whole thinning factors for the lithosphere have been determined from the water loaded subsidence. Results show that thermal subsidence alone cannot account for the observed subsidence, and that an additional initial subsidence is needed. Whole lithosphere thinning factors increase from an average of 0.5 to 0.8 across the Moresby Seamount eastwards towards the propagating tip. A satellite gravity inversion incorporating a lithosphere thermal gravity anomaly correction has been used to determine Moho depth, crustal thickness and thinning factors for the propagating tip in the Woodlark Basin. Moho depths are consistent with depths obtained from receiver function analysis (Ferris et al. 2006). Crustal thickness estimates do not include a correction for sediment thickness and are upper bounds. Crustal thinning factors in the vicinity of the Moresby Seamount are similar to those observed for the whole lithosphere. Fault analysis of the three 2D profiles have been used to determine upper crustal thinning factors. Upper crustal thinning factors between 0.1 to 0.2 are observed for the vicinity of the Moresby Seamount, substantially lower than thinning factors predicted for the whole lithosphere and continental crust, suggesting depth-dependent lithosphere thinning. Crustal thicknesses predicted from gravity inversion immediately to the east of the Moresby Seamount are substantially greater than would be expected for oceanic lithosphere in this region, while highly thinned, has not completely ruptured.

  5. A unified inversion scheme to process multifrequency measurements of various dispersive electromagnetic properties

    NASA Astrophysics Data System (ADS)

    Han, Y.; Misra, S.

    2018-04-01

    Multi-frequency measurement of a dispersive electromagnetic (EM) property, such as electrical conductivity, dielectric permittivity, or magnetic permeability, is commonly analyzed for purposes of material characterization. Such an analysis requires inversion of the multi-frequency measurement based on a specific relaxation model, such as Cole-Cole model or Pelton's model. We develop a unified inversion scheme that can be coupled to various type of relaxation models to independently process multi-frequency measurement of varied EM properties for purposes of improved EM-based geomaterial characterization. The proposed inversion scheme is firstly tested in few synthetic cases in which different relaxation models are coupled into the inversion scheme and then applied to multi-frequency complex conductivity, complex resistivity, complex permittivity, and complex impedance measurements. The method estimates up to seven relaxation-model parameters exhibiting convergence and accuracy for random initializations of the relaxation-model parameters within up to 3-orders of magnitude variation around the true parameter values. The proposed inversion method implements a bounded Levenberg algorithm with tuning initial values of damping parameter and its iterative adjustment factor, which are fixed in all the cases shown in this paper and irrespective of the type of measured EM property and the type of relaxation model. Notably, jump-out step and jump-back-in step are implemented as automated methods in the inversion scheme to prevent the inversion from getting trapped around local minima and to honor physical bounds of model parameters. The proposed inversion scheme can be easily used to process various types of EM measurements without major changes to the inversion scheme.

  6. Estimation of Random Medium Parameters from 2D Post-Stack Seismic Data and Its Application in Seismic Inversion

    NASA Astrophysics Data System (ADS)

    Yang, X.; Zhu, P.; Gu, Y.; Xu, Z.

    2015-12-01

    Small scale heterogeneities of subsurface medium can be characterized conveniently and effectively using a few simple random medium parameters (RMP), such as autocorrelation length, angle and roughness factor, etc. The estimation of these parameters is significant in both oil reservoir prediction and metallic mine exploration. Poor accuracy and low stability existed in current estimation approaches limit the application of random medium theory in seismic exploration. This study focuses on improving the accuracy and stability of RMP estimation from post-stacked seismic data and its application in the seismic inversion. Experiment and theory analysis indicate that, although the autocorrelation of random medium is related to those of corresponding post-stacked seismic data, the relationship is obviously affected by the seismic dominant frequency, the autocorrelation length, roughness factor and so on. Also the error of calculation of autocorrelation in the case of finite and discrete model decreases the accuracy. In order to improve the precision of estimation of RMP, we design two improved approaches. Firstly, we apply region growing algorithm, which often used in image processing, to reduce the influence of noise in the autocorrelation calculated by the power spectrum method. Secondly, the orientation of autocorrelation is used as a new constraint in the estimation algorithm. The numerical experiments proved that it is feasible. In addition, in post-stack seismic inversion of random medium, the estimated RMP may be used to constrain inverse procedure and to construct the initial model. The experiment results indicate that taking inversed model as random medium and using relatively accurate estimated RMP to construct initial model can get better inversion result, which contained more details conformed to the actual underground medium.

  7. Prognostic significance of inverse spatial QRS-T angle circadian pattern in myocardial infarction survivors.

    PubMed

    Giannopoulos, Georgios; Dilaveris, Polychronis; Batchvarov, Velislav; Synetos, Andreas; Hnatkova, Katerina; Gatzoulis, Konstantinos; Malik, Marek; Stefanadis, Christodoulos

    2009-01-01

    We investigated the predictive value of the spatial QRS-T angle (QRSTA) circadian variation in myocardial infarction (MI) patients. Analyzing 24-hour recordings (SEER MC, GE Marquette) from 151 MI patients (age 63 +/- 12.7), the QRSTA was computed in derived XYZ leads. QRS-T angle values were compared between daytime and night time. The end point was cardiac death or life-threatening ventricular arrhythmia in 1 year. Overall, QRSTA was slightly higher during the day vs. the night (91 degrees vs. 87 degrees, P = .005). However, 33.8% of the patients showed an inverse diurnal QRSTA variation (higher values at night), which was correlated to the outcome (P = .001, odds ratio 6.7). In multivariate analysis, after entering all factors exhibiting univariate trend towards significance, inverse QRSTA circadian pattern remained significant (P = .036). Inverse QRSTA circadian pattern was found to be associated with adverse outcome (22.4%) in MI patients, whereas a normal pattern was associated (96%) with a favorable outcome.

  8. Inverse Problems in Complex Models and Applications to Earth Sciences

    NASA Astrophysics Data System (ADS)

    Bosch, M. E.

    2015-12-01

    The inference of the subsurface earth structure and properties requires the integration of different types of data, information and knowledge, by combined processes of analysis and synthesis. To support the process of integrating information, the regular concept of data inversion is evolving to expand its application to models with multiple inner components (properties, scales, structural parameters) that explain multiple data (geophysical survey data, well-logs, core data). The probabilistic inference methods provide the natural framework for the formulation of these problems, considering a posterior probability density function (PDF) that combines the information from a prior information PDF and the new sets of observations. To formulate the posterior PDF in the context of multiple datasets, the data likelihood functions are factorized assuming independence of uncertainties for data originating across different surveys. A realistic description of the earth medium requires modeling several properties and structural parameters, which relate to each other according to dependency and independency notions. Thus, conditional probabilities across model components also factorize. A common setting proceeds by structuring the model parameter space in hierarchical layers. A primary layer (e.g. lithology) conditions a secondary layer (e.g. physical medium properties), which conditions a third layer (e.g. geophysical data). In general, less structured relations within model components and data emerge from the analysis of other inverse problems. They can be described with flexibility via direct acyclic graphs, which are graphs that map dependency relations between the model components. Examples of inverse problems in complex models can be shown at various scales. At local scale, for example, the distribution of gas saturation is inferred from pre-stack seismic data and a calibrated rock-physics model. At regional scale, joint inversion of gravity and magnetic data is applied for the estimation of lithological structure of the crust, with the lithotype body regions conditioning the mass density and magnetic susceptibility fields. At planetary scale, the Earth mantle temperature and element composition is inferred from seismic travel-time and geodetic data.

  9. Public and private healthcare services utilization by non-institutional elderly in Hong Kong: is the inverse care law operating?

    PubMed

    Yam, Ho-Kwan; Mercer, Stewart W; Wong, Lai-Yi; Chan, Wan-Kin; Yeoh, Eng-Kiong

    2009-08-01

    To assess the factors associated with healthcare services utilization by the non-institutional elderly across five types of service utilization (Western medicine doctors in Government clinics, private Western medicine doctors, Chinese medicine practitioners, Emergency Units, and hospitalization). A secondary data analysis of a territory-wide cross-sectional survey collected by the Government among a representative sample of 4812 elderly (aged 60 and above) in Hong Kong. Our analysis, based on Anderson's behavioral framework, shows that need factors (relating to actual or perceived illness and diseases) are significantly related to the healthcare services utilization examined. However, enabling factors, such as monthly household income per capita, play a significant role in determining the utilization. Although the lower-income elderly consult more Government clinics and less private clinics than the more affluent, they have a lower total utilization of healthcare services despite having significantly greater healthcare needs. This suggests a mismatch of need and supply within the mixed economy of private and public healthcare services and suggests the existence of an 'inverse care law' in Hong Kong amongst elderly citizens. The findings raise concerns of inequities in Hong Kong's healthcare system, raising implications for future healthcare reforms.

  10. Diet quality and the influence of social and physical factors on food consumption and nutrient intake in materially deprived older people.

    PubMed

    Holmes, B A; Roberts, C L

    2011-04-01

    To investigate the influence of social and physical factors on diet quality in materially deprived (low income) older people in the United Kingdom. A diet quality index was obtained for 222 men and 440 women aged 65 and over living alone or with other adults of retirement age from the United Kingdom Low Income Diet and Nutrition Survey (2003-2005). The association between diet quality and social and physical factors was investigated by logistic regression analysis. Analysis revealed several barriers to an adequate diet in the older low-income population. For both men and women, having the best quality diet was inversely associated with usually eating meals on one's lap as opposed to at the table (Adjusted odds ratio (ORs)=0.3, 95% confidence interval: 0.12-0.77 (men), 0.3, 0.17-0.56 (women)). For men, difficulty chewing was inversely associated with the best quality diet (OR=0.4; 0.13-0.99), whereas for women, current smoking and being 75 years or over were inversely associated with the best quality diet (OR=0.2; 0.06-0.42 and 0.5; 0.27-0.87, respectively); P value for all associations was <0.05. Results suggest that the social setting is an important determinant of diet quality in this group and future studies should collect details on where and with whom meals are taken to fully investigate the extent of this influence. © 2011 Macmillan Publishers Limited All rights reserved

  11. Generalizability of dietary patterns of the inverse association between alcohol consumption and type 2 diabetes risk

    USDA-ARS?s Scientific Manuscript database

    Epidemiology of dietary components and disease risk limits interpretability due to potential residual confounding by correlated dietary components. Dietary pattern analyses by factor analysis or partial least squares may overcome this limitation. To examine confounding by dietary pattern as well as ...

  12. Confounding by dietary pattern of the inverse association between alcohol consumption and type 2 diabetes risk

    USDA-ARS?s Scientific Manuscript database

    Epidemiology of dietary components and disease risk limits interpretability due to potential residual confounding by correlated dietary components. Dietary pattern analyses by factor analysis or partial least squares may overcome the limitation. To examine confounding by dietary pattern as well as ...

  13. Confounding by dietary patterns of the inverse association between alcohol consumption and type 2 diabetes risk

    USDA-ARS?s Scientific Manuscript database

    Epidemiology of dietary components and disease risk limits interpretability due to potential residual confounding by correlated dietary components. Dietary pattern analyses by factor analysis or partial least squares may overcome this limitation. To examine confounding by dietary pattern as well as ...

  14. The Correlates of Body Composition with Heart Rate Recovery after Step Test: An Exploratory Study of Malaysian Adolescents

    PubMed Central

    Abu Hanifah, Redzal; Mohamed, Mohd. Nahar Azmi; Jaafar, Zulkarnain; Abdul Mohsein, Nabilla Al-Sadat; Jalaludin, Muhammad Yazid; Abdul Majid, Hazreen; Murray, Liam; Cantwell, Marie; Su, Tin Tin

    2013-01-01

    Background In adults, heart rate recovery is a predictor of mortality, while in adolescents it is associated with cardio-metabolic risk factors. The aim of this study was to examine the relationship between body composition measures and heart rate recovery (HRR) after step test in Malaysian secondary school students. Methods In the Malaysian Health and Adolescents Longitudinal Research Team (MyHEART) study, 1071 healthy secondary school students, aged 13 years old, participated in the step test. Parameters for body composition measures were body mass index z-score, body fat percentage, waist circumference, and waist height ratio. The step test was conducted by using a modified Harvard step test. Heart rate recovery of 1 minute (HRR1min) and heart rate recovery of 2 minutes (HRR2min) were calculated by the difference between the peak pulse rate during exercise and the resting pulse rate at 1 and 2 minutes, respectively. Analysis was done separately based on gender. Pearson correlation analysis was used to determine the association between the HRR parameters with body composition measures, while multiple regression analysis was used to determine which body composition measures was the strongest predictor for HRR. Results For both gender groups, all body composition measures were inversely correlated with HRR1min. In girls, all body composition measures were inversely correlated with HRR2min, while in boys all body composition measures, except BMI z-score, were associated with HRR2min. In multiple regression, only waist circumference was inversely associated with HRR2min (p=0.024) in boys, while in girls it was body fat percentage for HRR2min (p=0.008). Conclusion There was an inverse association between body composition measurements and HRR among apparently healthy adolescents. Therefore, it is important to identify cardio-metabolic risk factors in adolescent as an early prevention of consequent adulthood morbidity. This reiterates the importance of healthy living which should start from young. PMID:24349388

  15. Inverse Scattering and Local Observable Algebras in Integrable Quantum Field Theories

    NASA Astrophysics Data System (ADS)

    Alazzawi, Sabina; Lechner, Gandalf

    2017-09-01

    We present a solution method for the inverse scattering problem for integrable two-dimensional relativistic quantum field theories, specified in terms of a given massive single particle spectrum and a factorizing S-matrix. An arbitrary number of massive particles transforming under an arbitrary compact global gauge group is allowed, thereby generalizing previous constructions of scalar theories. The two-particle S-matrix S is assumed to be an analytic solution of the Yang-Baxter equation with standard properties, including unitarity, TCP invariance, and crossing symmetry. Using methods from operator algebras and complex analysis, we identify sufficient criteria on S that imply the solution of the inverse scattering problem. These conditions are shown to be satisfied in particular by so-called diagonal S-matrices, but presumably also in other cases such as the O( N)-invariant nonlinear {σ}-models.

  16. Sunnier European countries have lower melanoma mortality.

    PubMed

    Shipman, A R; Clark, A B; Levell, N J

    2011-07-01

    Doubt has been cast on sunlight as the major causative factor for malignant melanoma. We performed statistical analysis of the average annual sunlight hours in 36 European capital cities compared with the country's melanoma mortality rate. A significant inverse proportionality was identified in both men and women, indicating that sun exposure is unlikely to be the strongest factor affecting mortality from malignant melanoma. © The Author(s). CED © 2011 British Association of Dermatologists.

  17. IMPROVED SEARCH OF PRINCIPAL COMPONENT ANALYSIS DATABASES FOR SPECTRO-POLARIMETRIC INVERSION

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Casini, R.; Lites, B. W.; Ramos, A. Asensio

    2013-08-20

    We describe a simple technique for the acceleration of spectro-polarimetric inversions based on principal component analysis (PCA) of Stokes profiles. This technique involves the indexing of the database models based on the sign of the projections (PCA coefficients) of the first few relevant orders of principal components of the four Stokes parameters. In this way, each model in the database can be attributed a distinctive binary number of 2{sup 4n} bits, where n is the number of PCA orders used for the indexing. Each of these binary numbers (indices) identifies a group of ''compatible'' models for the inversion of amore » given set of observed Stokes profiles sharing the same index. The complete set of the binary numbers so constructed evidently determines a partition of the database. The search of the database for the PCA inversion of spectro-polarimetric data can profit greatly from this indexing. In practical cases it becomes possible to approach the ideal acceleration factor of 2{sup 4n} as compared to the systematic search of a non-indexed database for a traditional PCA inversion. This indexing method relies on the existence of a physical meaning in the sign of the PCA coefficients of a model. For this reason, the presence of model ambiguities and of spectro-polarimetric noise in the observations limits in practice the number n of relevant PCA orders that can be used for the indexing.« less

  18. Noise removal using factor analysis of dynamic structures: application to cardiac gated studies.

    PubMed

    Bruyant, P P; Sau, J; Mallet, J J

    1999-10-01

    Factor analysis of dynamic structures (FADS) facilitates the extraction of relevant data, usually with physiologic meaning, from a dynamic set of images. The result of this process is a set of factor images and curves plus some residual activity. The set of factor images and curves can be used to retrieve the original data with reduced noise using an inverse factor analysis process (iFADS). This improvement in image quality is expected because the inverse process does not use the residual activity, assumed to be made of noise. The goal of this work is to quantitate and assess the efficiency of this method on gated cardiac images. A computer simulation of a planar cardiac gated study was performed. The simulated images were added with noise and processed by the FADS-iFADS program. The signal-to-noise ratios (SNRs) were compared between original and processed data. Planar gated cardiac studies from 10 patients were tested. The data processed by FADS-iFADS were subtracted to the original data. The result of the substraction was studied to evaluate its noisy nature. The SNR is about five times greater after the FADS-iFADS process. The difference between original and processed data is noise only, i.e., processed data equals original data minus some white noise. The FADS-iFADS process is successful in the removal of an important part of the noise and therefore is a tool to improve the image quality of cardiac images. This tool does not decrease the spatial resolution (compared with smoothing filters) and does not lose details (compared with frequential filters). Once the number of factors is chosen, this method is not operator dependent.

  19. MEG-SIM: a web portal for testing MEG analysis methods using realistic simulated and empirical data.

    PubMed

    Aine, C J; Sanfratello, L; Ranken, D; Best, E; MacArthur, J A; Wallace, T; Gilliam, K; Donahue, C H; Montaño, R; Bryant, J E; Scott, A; Stephen, J M

    2012-04-01

    MEG and EEG measure electrophysiological activity in the brain with exquisite temporal resolution. Because of this unique strength relative to noninvasive hemodynamic-based measures (fMRI, PET), the complementary nature of hemodynamic and electrophysiological techniques is becoming more widely recognized (e.g., Human Connectome Project). However, the available analysis methods for solving the inverse problem for MEG and EEG have not been compared and standardized to the extent that they have for fMRI/PET. A number of factors, including the non-uniqueness of the solution to the inverse problem for MEG/EEG, have led to multiple analysis techniques which have not been tested on consistent datasets, making direct comparisons of techniques challenging (or impossible). Since each of the methods is known to have their own set of strengths and weaknesses, it would be beneficial to quantify them. Toward this end, we are announcing the establishment of a website containing an extensive series of realistic simulated data for testing purposes ( http://cobre.mrn.org/megsim/ ). Here, we present: 1) a brief overview of the basic types of inverse procedures; 2) the rationale and description of the testbed created; and 3) cases emphasizing functional connectivity (e.g., oscillatory activity) suitable for a wide assortment of analyses including independent component analysis (ICA), Granger Causality/Directed transfer function, and single-trial analysis.

  20. MEG-SIM: A Web Portal for Testing MEG Analysis Methods using Realistic Simulated and Empirical Data

    PubMed Central

    Aine, C. J.; Sanfratello, L.; Ranken, D.; Best, E.; MacArthur, J. A.; Wallace, T.; Gilliam, K.; Donahue, C. H.; Montaño, R.; Bryant, J. E.; Scott, A.; Stephen, J. M.

    2012-01-01

    MEG and EEG measure electrophysiological activity in the brain with exquisite temporal resolution. Because of this unique strength relative to noninvasive hemodynamic-based measures (fMRI, PET), the complementary nature of hemodynamic and electrophysiological techniques is becoming more widely recognized (e.g., Human Connectome Project). However, the available analysis methods for solving the inverse problem for MEG and EEG have not been compared and standardized to the extent that they have for fMRI/PET. A number of factors, including the non-uniqueness of the solution to the inverse problem for MEG/EEG, have led to multiple analysis techniques which have not been tested on consistent datasets, making direct comparisons of techniques challenging (or impossible). Since each of the methods is known to have their own set of strengths and weaknesses, it would be beneficial to quantify them. Toward this end, we are announcing the establishment of a website containing an extensive series of realistic simulated data for testing purposes (http://cobre.mrn.org/megsim/). Here, we present: 1) a brief overview of the basic types of inverse procedures; 2) the rationale and description of the testbed created; and 3) cases emphasizing functional connectivity (e.g., oscillatory activity) suitable for a wide assortment of analyses including independent component analysis (ICA), Granger Causality/Directed transfer function, and single-trial analysis. PMID:22068921

  1. Prevalence of the intron 22 inversion of the factor VIII gene and inhibitor development in Polish patients with severe hemophilia A.

    PubMed

    Sawecka, Jadwiga; Skulimowska, Joanna; Windyga, Jerzy; Lopaciuk, Stanisław; Kościelak, Jerzy

    2005-01-01

    Patients with severe hemophilia A often develop inhibitors (antibodies) against transfused factor VIII. One hundred thirteen Polish patients with severe hemophilia A, who had been treated on demand with cryoprecipitate until 1992 and exclusively with factor VIII concentrates after 1995, were examined for intron 22 inversion by Southern blotting and the presence and magnitude of inhibitor activity in blood as determined by the Bethesda assay. The patients' ages ranged 4--67 years (mean: 33.7+/-12.4 years, median: 32 years). The number of patients with the inversion amounted to 57, while in 56 patients the mutation types were unknown; 47 patients had a distal and 10 patients a proximal type of inversion. Thirteen patients with inversions (22.8%) were found to have inhibitor in their blood. Most patients (14 out of 15) who developed inhibitors in the course of cryoprecipitate therapy were high responders. Conversely, 4 of 5 patients treated between 1992 and 1995 with both cryoprecipitate and intermediate-purity factor VIII concentrates were low responders. One multitransfused patient who had remained inhibitor-free on cryoprecipitate therapy developed inhibitor after receiving a large dose of factor VIII concentrate during surgery. None of these 5 patients developed inhibitors during their 12--40 years of treatment with cryoprecipitate, suggesting that it was less immunogenic than factor VIII concentrates. The prevalence of the intron 22 inversion mutation of the factor VIII gene in Polish hemophiliacs is similar to that in other European countries. Treatment regimens with either cryoprecipitate or virus-inactivated plasma-derived factor VIII concentrates may affect inhibitor formation in hemophilia A patients.

  2. Inversion analysis of estimating interannual variability and its uncertainties in biotic and abiotic parameters of a parsimonious physiologically based model after wind disturbance

    NASA Astrophysics Data System (ADS)

    Toda, M.; Yokozawa, M.; Richardson, A. D.; Kohyama, T.

    2011-12-01

    The effects of wind disturbance on interannual variability in ecosystem CO2 exchange have been assessed in two forests in northern Japan, i.e., a young, even-aged, monocultured, deciduous forest and an uneven-aged mixed forest of evergreen and deciduous trees, including some over 200 years old using eddy covariance (EC) measurements during 2004-2008. The EC measurements have indicated that photosynthetic recovery of trees after a huge typhoon occurred during early September in 2004 activated annual carbon uptake of both forests due to changes in physiological response of tree leaves during their growth stages. However, little have been resolved about what biotic and abiotic factors regulated interannual variability in heat, water and carbon exchange between an atmosphere and forests. In recent years, an inverse modeling analysis has been utilized as a powerful tool to estimate biotic and abiotic parameters that might affect heat, water and CO2 exchange between the atmosphere and forest of a parsimonious physiologically based model. We conducted the Bayesian inverse model analysis for the model with the EC measurements. The preliminary result showed that the above model-derived NEE values were consistent with observed ones on the hourly basis with optimized parameters by Baysian inversion. In the presentation, we would examine interannual variability in biotic and abiotic parameters related to heat, water and carbon exchange between the atmosphere and forests after disturbance by typhoon.

  3. Pre-Eclampsia, Birth Weight, and Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Mann, Joshua R.; McDermott, Suzanne; Bao, Haikun; Hardin, James; Gregg, Anthony

    2010-01-01

    Autism spectrum disorders (ASD) are primarily inherited, but perinatal or other environmental factors may also be important. In an analysis of 87,677 births from 1996 through 2002, insured by the South Carolina Medicaid program, birth weight was significantly inversely associated with the odds of ASD (OR = 0.78, p = 0.001 for each additional…

  4. The association of educational attainment and SBP among older community-living adults: the Maintenance of Balance, Independent Living, Intellect and Zest in the Elderly (MOBILIZE) Boston Study.

    PubMed

    Kiely, Dan K; Gross, Alden L; Kim, Dae H; Lipsitz, Lewis A

    2012-08-01

    Educational attainment is inversely associated with SBP level in young adulthood. This association has not been studied in an older cohort, and confounding and mediating factors are not well known. The authors hypothesized that higher education is associated with lower levels of SBP independent of many risk factors for hypertension. This prospective observational study included a sample of 764 older community-living participants in the Maintenance of Balance, Independent Living, Intellect and Zest in the Elderly (MOBILIZE) Boston Study. Compared to participants with more than college education, regression analyses showed those with a high school education or less had a SBP value 6.33 mmHg higher [95% confidence interval (CI): 2.55-10.10], and those who had a college education had a SBP value 4.01 mmHg higher (95% CI: 0.77-7.25) independent of many hypothesized confounders and mediators. Results of a path analysis confirmed that higher level of education was associated with lower SBP even after adjustment for hypothesized mediators. Although slightly attenuated by multivariable adjustment for hypertension risk factors, the significant inverse association between educational attainment and SBP was not entirely mediated by these risk factors. These findings indicate that education is inversely associated with SBP in a diverse cohort of community-living older adults, independent of many known or suspected risk factors. This study is the first to report the association between education and SBP in an older sample, representing a population at the highest risk for hypertension-related morbidity and mortality.

  5. The Effect of Flow Velocity on Waveform Inversion

    NASA Astrophysics Data System (ADS)

    Lee, D.; Shin, S.; Chung, W.; Ha, J.; Lim, Y.; Kim, S.

    2017-12-01

    The waveform inversion is a velocity modeling technique that reconstructs accurate subsurface physical properties. Therefore, using the model in its final, updated version, we generated data identical to modeled data. Flow velocity, like several other factors, affects observed data in seismic exploration. Despite this, there is insufficient research on its relationship with waveform inversion. In this study, the generated synthetic data considering flow velocity was factored in waveform inversion and the influence of flow velocity in waveform inversion was analyzed. Measuring the flow velocity generally requires additional equipment. However, for situations where only seismic data was available, flow velocity was calculated by fixed-point iteration method using direct wave in observed data. Further, a new waveform inversion was proposed, which can be applied to the calculated flow velocity. We used a wave equation, which can work with the flow velocities used in the study by Käser and Dumbser. Further, we enhanced the efficiency of computation by applying the back-propagation method. To verify the proposed algorithm, six different data sets were generated using the Marmousi2 model; each of these data sets used different flow velocities in the range 0-50, i.e., 0, 2, 5, 10, 25, and 50. Thereafter, the inversion results from these data sets along with the results without the use of flow velocity were compared and analyzed. In this study, we analyzed the results of waveform inversion after flow velocity has been factored in. It was demonstrated that the waveform inversion is not affected significantly when the flow velocity is of smaller value. However, when the flow velocity has a large value, factoring it in the waveform inversion produces superior results. This research was supported by the Basic Research Project(17-3312, 17-3313) of the Korea Institute of Geoscience and Mineral Resources(KIGAM) funded by the Ministry of Science, ICT and Future Planning of Korea.

  6. Working conditions, self-perceived stress, anxiety, depression and quality of life: A structural equation modelling approach

    PubMed Central

    Rusli, Bin Nordin; Edimansyah, Bin Abdin; Naing, Lin

    2008-01-01

    Background The relationships between working conditions [job demand, job control and social support]; stress, anxiety, and depression; and perceived quality of life factors [physical health, psychological wellbeing, social relationships and environmental conditions] were assessed using a sample of 698 male automotive assembly workers in Malaysia. Methods The validated Malay version of the Job Content Questionnaire (JCQ), Depression Anxiety Stress Scales (DASS) and the World Health Organization Quality of Life-Brief (WHOQOL-BREF) were used. A structural equation modelling (SEM) analysis was applied to test the structural relationships of the model using AMOS version 6.0, with the maximum likelihood ratio as the method of estimation. Results The results of the SEM supported the hypothesized structural model (χ2 = 22.801, df = 19, p = 0.246). The final model shows that social support (JCQ) was directly related to all 4 factors of the WHOQOL-BREF and inversely related to depression and stress (DASS). Job demand (JCQ) was directly related to stress (DASS) and inversely related to the environmental conditions (WHOQOL-BREF). Job control (JCQ) was directly related to social relationships (WHOQOL-BREF). Stress (DASS) was directly related to anxiety and depression (DASS) and inversely related to physical health, environment conditions and social relationships (WHOQOL-BREF). Anxiety (DASS) was directly related to depression (DASS) and inversely related to physical health (WHOQOL-BREF). Depression (DASS) was inversely related to the psychological wellbeing (WHOQOL-BREF). Finally, stress, anxiety and depression (DASS) mediate the relationships between job demand and social support (JCQ) to the 4 factors of WHOQOL-BREF. Conclusion These findings suggest that higher social support increases the self-reported quality of life of these workers. Higher job control increases the social relationships, whilst higher job demand increases the self-perceived stress and decreases the self-perceived quality of life related to environmental factors. The mediating role of depression, anxiety and stress on the relationship between working conditions and perceived quality of life in automotive workers should be taken into account in managing stress amongst these workers. PMID:18254966

  7. Working conditions, self-perceived stress, anxiety, depression and quality of life: a structural equation modelling approach.

    PubMed

    Rusli, Bin Nordin; Edimansyah, Bin Abdin; Naing, Lin

    2008-02-06

    The relationships between working conditions [job demand, job control and social support]; stress, anxiety, and depression; and perceived quality of life factors [physical health, psychological wellbeing, social relationships and environmental conditions] were assessed using a sample of 698 male automotive assembly workers in Malaysia. The validated Malay version of the Job Content Questionnaire (JCQ), Depression Anxiety Stress Scales (DASS) and the World Health Organization Quality of Life-Brief (WHOQOL-BREF) were used. A structural equation modelling (SEM) analysis was applied to test the structural relationships of the model using AMOS version 6.0, with the maximum likelihood ratio as the method of estimation. The results of the SEM supported the hypothesized structural model (chi2 = 22.801, df = 19, p = 0.246). The final model shows that social support (JCQ) was directly related to all 4 factors of the WHOQOL-BREF and inversely related to depression and stress (DASS). Job demand (JCQ) was directly related to stress (DASS) and inversely related to the environmental conditions (WHOQOL-BREF). Job control (JCQ) was directly related to social relationships (WHOQOL-BREF). Stress (DASS) was directly related to anxiety and depression (DASS) and inversely related to physical health, environment conditions and social relationships (WHOQOL-BREF). Anxiety (DASS) was directly related to depression (DASS) and inversely related to physical health (WHOQOL-BREF). Depression (DASS) was inversely related to the psychological wellbeing (WHOQOL-BREF). Finally, stress, anxiety and depression (DASS) mediate the relationships between job demand and social support (JCQ) to the 4 factors of WHOQOL-BREF. These findings suggest that higher social support increases the self-reported quality of life of these workers. Higher job control increases the social relationships, whilst higher job demand increases the self-perceived stress and decreases the self-perceived quality of life related to environmental factors. The mediating role of depression, anxiety and stress on the relationship between working conditions and perceived quality of life in automotive workers should be taken into account in managing stress amongst these workers.

  8. Comparison of Predictive Factors for Postoperative Incontinence of Holmium Laser Enucleation of the Prostate by the Surgeons' Experience During Learning Curve.

    PubMed

    Shigemura, Katsumi; Tanaka, Kazushi; Yamamichi, Fukashi; Chiba, Koji; Fujisawa, Masato

    2016-03-01

    To detect predictive factors for postoperative incontinence following holmium laser enucleation of the prostate (HoLEP) according to surgeon experience (beginner or experienced) and preoperative clinical data. Of 224 patients, a total of 203 with available data on incontinence were investigated. The potential predictive factors for post-HoLEP incontinence included clinical factors, such as patient age, and preoperative urodynamic study results, including detrusor overactivity (DO). We also classified the surgeons performing the procedure according to their HoLEP experience: beginner (<21 cases) and experienced (≥21 cases). Our statistical data showed DO was a significant predictive factor at the super-short period (the next day of catheter removal: odds ratio [OR], 3.375; P=0.000). Additionally, patient age, surgeon mentorship (inverse correlation), and prostate volume were significant predictive factors at the 1-month interval after HoLEP (OR, 1.072; P=0.004; OR, 0.251; P=0.002; and OR, 1.008; P=0.049, respectively). With regards to surgeon experience, DO and preoperative International Prostate Symptom Score (inverse) at the super-short period, and patient age and mentorship (inverse correlation) at the 1-month interval after HoLEP (OR, 3.952; P=0.002; OR, 1.084; P=0.015; and OR,1.084; P=0.015; OR, 0.358; P=0.003, respectively) were significant predictive factors for beginners, and first desire to void (FDV) at 1 month after HoLEP (OR, 1.009; P=0.012) was a significant predictive factor for experienced surgeons in multivariate analysis. Preoperative DO, IPSS, patient age, and surgeon mentorship were significant predictive factors of postoperative patient incontinence for beginner surgeons, while FDV was a significant predictive factors for experienced surgeons. These findings should be taken into account by surgeons performing HoLEP to maximize the patient's quality of life with regards to urinary continence.

  9. Civilian helicopter accidents into water: analysis of 46 cases, 1979-2006.

    PubMed

    Brooks, Christopher James; MacDonald, Conor Vaughan; Donati, Leo; Taber, Michael John

    2008-10-01

    When a helicopter crashes or ditches into water the crew and passengers must often make an escape from underwater and a number of the occupants do not survive. This paper examined fatality rates, human factors problems with escape, and causes of death in Canadian civilian registered helicopter accidents in water (1979-2006). Data obtained from the Transportation Safety Board of Canada was reviewed. Key issues such as fatalities, injuries, warning time, sinking, and inversion were examined. There were 46 helicopters that ditched into water. There were 124 crew and passengers involved. Of those, 27 (23%) crew and passengers died. Lack of warning time (55%), rapid sinking (72%), and inversion (35%) were the most common issues in the accidents. Survival rates for Canadian registered helicopter accidents into water (78%) show little change from previously reported worldwide data. Lack of warning time, rapid sinking, and inversion were the significant factors in the survival rate. The practical implication is that crew and passengers involved in planned flights over water must wear all the life support equipment on strap-in and not have it stowed on the back of the seat or in the cabin.

  10. A new phase correction method in NMR imaging based on autocorrelation and histogram analysis.

    PubMed

    Ahn, C B; Cho, Z H

    1987-01-01

    A new statistical approach to phase correction in NMR imaging is proposed. The proposed scheme consists of first-and zero-order phase corrections each by the inverse multiplication of estimated phase error. The first-order error is estimated by the phase of autocorrelation calculated from the complex valued phase distorted image while the zero-order correction factor is extracted from the histogram of phase distribution of the first-order corrected image. Since all the correction procedures are performed on the spatial domain after completion of data acquisition, no prior adjustments or additional measurements are required. The algorithm can be applicable to most of the phase-involved NMR imaging techniques including inversion recovery imaging, quadrature modulated imaging, spectroscopic imaging, and flow imaging, etc. Some experimental results with inversion recovery imaging as well as quadrature spectroscopic imaging are shown to demonstrate the usefulness of the algorithm.

  11. Landscape of dietary factors associated with risk of gastric cancer: A systematic review and dose-response meta-analysis of prospective cohort studies.

    PubMed

    Fang, Xuexian; Wei, Jiayu; He, Xuyan; An, Peng; Wang, Hao; Jiang, Li; Shao, Dandan; Liang, Han; Li, Yi; Wang, Fudi; Min, Junxia

    2015-12-01

    The associations between dietary factors and gastric cancer risk have been analysed by many studies, but with inconclusive results. We conducted a meta-analysis of prospective studies to systematically investigate the associations. Relevant studies were identified through searching Medline, Embase, and Web of Science up to June 30, 2015. We included prospective cohort studies of intake of dietary factors with risk estimates and 95% confidence intervals for gastric cancer. Seventy-six prospective cohort studies were eligible and included in the analysis. We ascertained 32,758 gastric cancer cases out of 6,316,385 participants in relations to intake of 67 dietary factors, covering a wide ranging of vegetables, fruit, meat, fish, salt, alcohol, tea, coffee, and nutrients, during 3.3 to 30 years of follow-up. Evidence from this study indicates that consumption of total fruit and white vegetables, but not total vegetables, was inversely associated with gastric cancer risk. Both fruit and white vegetables are rich sources of vitamin C, which showed significant protective effect against gastric cancer by our analysis too. Furthermore, we found concordant positive associations between high-salt foods and gastric cancer risk. In addition, a strong effect of alcohol consumption, particularly beer and liquor but not wine, on gastric cancer risk was observed compared with nondrinkers. Dose-response analysis indicated that risk of gastric cancer was increased by 12% per 5 g/day increment of dietary salt intake or 5% per 10 g/day increment of alcohol consumption, and that a 100 g/day increment of fruit consumption was inversely associated with 5% reduction of risk. This study provides comprehensive and strong evidence that there are a number of protective and risk factors for gastric cancer in diet. Our findings may have significant public health implications with regard to prevention of gastric cancer and provide insights into future cohort studies and the design of related clinical trials. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. The analysis of a rocket tomography measurement of the N2+3914A emission and N2 ionization rates in an auroral arc

    NASA Technical Reports Server (NTRS)

    Mcdade, Ian C.

    1991-01-01

    Techniques were developed for recovering two-dimensional distributions of auroral volume emission rates from rocket photometer measurements made in a tomographic spin scan mode. These tomographic inversion procedures are based upon an algebraic reconstruction technique (ART) and utilize two different iterative relaxation techniques for solving the problems associated with noise in the observational data. One of the inversion algorithms is based upon a least squares method and the other on a maximum probability approach. The performance of the inversion algorithms, and the limitations of the rocket tomography technique, were critically assessed using various factors such as (1) statistical and non-statistical noise in the observational data, (2) rocket penetration of the auroral form, (3) background sources of emission, (4) smearing due to the photometer field of view, and (5) temporal variations in the auroral form. These tests show that the inversion procedures may be successfully applied to rocket observations made in medium intensity aurora with standard rocket photometer instruments. The inversion procedures have been used to recover two-dimensional distributions of auroral emission rates and ionization rates from an existing set of N2+3914A rocket photometer measurements which were made in a tomographic spin scan mode during the ARIES auroral campaign. The two-dimensional distributions of the 3914A volume emission rates recoverd from the inversion of the rocket data compare very well with the distributions that were inferred from ground-based measurements using triangulation-tomography techniques and the N2 ionization rates derived from the rocket tomography results are in very good agreement with the in situ particle measurements that were made during the flight. Three pre-prints describing the tomographic inversion techniques and the tomographic analysis of the ARIES rocket data are included as appendices.

  13. Time-domain induced polarization - an analysis of Cole-Cole parameter resolution and correlation using Markov Chain Monte Carlo inversion

    NASA Astrophysics Data System (ADS)

    Madsen, Line Meldgaard; Fiandaca, Gianluca; Auken, Esben; Christiansen, Anders Vest

    2017-12-01

    The application of time-domain induced polarization (TDIP) is increasing with advances in acquisition techniques, data processing and spectral inversion schemes. An inversion of TDIP data for the spectral Cole-Cole parameters is a non-linear problem, but by applying a 1-D Markov Chain Monte Carlo (MCMC) inversion algorithm, a full non-linear uncertainty analysis of the parameters and the parameter correlations can be accessed. This is essential to understand to what degree the spectral Cole-Cole parameters can be resolved from TDIP data. MCMC inversions of synthetic TDIP data, which show bell-shaped probability distributions with a single maximum, show that the Cole-Cole parameters can be resolved from TDIP data if an acquisition range above two decades in time is applied. Linear correlations between the Cole-Cole parameters are observed and by decreasing the acquisitions ranges, the correlations increase and become non-linear. It is further investigated how waveform and parameter values influence the resolution of the Cole-Cole parameters. A limiting factor is the value of the frequency exponent, C. As C decreases, the resolution of all the Cole-Cole parameters decreases and the results become increasingly non-linear. While the values of the time constant, τ, must be in the acquisition range to resolve the parameters well, the choice between a 50 per cent and a 100 per cent duty cycle for the current injection does not have an influence on the parameter resolution. The limits of resolution and linearity are also studied in a comparison between the MCMC and a linearized gradient-based inversion approach. The two methods are consistent for resolved models, but the linearized approach tends to underestimate the uncertainties for poorly resolved parameters due to the corresponding non-linear features. Finally, an MCMC inversion of 1-D field data verifies that spectral Cole-Cole parameters can also be resolved from TD field measurements.

  14. Collaborative Investigations of Shallow Water Optics Problems

    DTIC Science & Technology

    2004-12-01

    Appendix E. Reprint of Radiative transfer equation inversion: Theory and shape factor models for retrieval of oceanic inherent optical properties, by F ...4829-4834. 5 Hoge, F . E., P. E. Lyon, C. D. Mobley, and L. K. Sundman, 2003. Radiative transfer equation inversion: Theory and shape factor models for...multilinear regression algorithms for the inversion of synthetic ocean colour spectra,, Int. J. Remote Sensing, 25(21), 4829-4834. Hoge, F . E., P. E. Lyon

  15. Porosity Estimation By Artificial Neural Networks Inversion . Application to Algerian South Field

    NASA Astrophysics Data System (ADS)

    Eladj, Said; Aliouane, Leila; Ouadfeul, Sid-Ali

    2017-04-01

    One of the main geophysicist's current challenge is the discovery and the study of stratigraphic traps, this last is a difficult task and requires a very fine analysis of the seismic data. The seismic data inversion allows obtaining lithological and stratigraphic information for the reservoir characterization . However, when solving the inverse problem we encounter difficult problems such as: Non-existence and non-uniqueness of the solution add to this the instability of the processing algorithm. Therefore, uncertainties in the data and the non-linearity of the relationship between the data and the parameters must be taken seriously. In this case, the artificial intelligence techniques such as Artificial Neural Networks(ANN) is used to resolve this ambiguity, this can be done by integrating different physical properties data which requires a supervised learning methods. In this work, we invert the acoustic impedance 3D seismic cube using the colored inversion method, then, the introduction of the acoustic impedance volume resulting from the first step as an input of based model inversion method allows to calculate the Porosity volume using the Multilayer Perceptron Artificial Neural Network. Application to an Algerian South hydrocarbon field clearly demonstrate the power of the proposed processing technique to predict the porosity for seismic data, obtained results can be used for reserves estimation, permeability prediction, recovery factor and reservoir monitoring. Keywords: Artificial Neural Networks, inversion, non-uniqueness , nonlinear, 3D porosity volume, reservoir characterization .

  16. The effect of subtalar inversion/eversion on the dynamic function of the tibialis anterior, soleus, and gastrocnemius during the stance phase of gait.

    PubMed

    Wang, Ruoli; Gutierrez-Farewik, Elena M

    2011-05-01

    The purpose of this study was to determine how gait deviation in one plane (i.e. excessive subtalar inversion/eversion) can affect the dynamic function of the tibialis anterior, gastrocnemius, and soleus to accelerate the subtalar, ankle, knee and hip joints, as well as the body center of mass. Induced acceleration analysis was performed based on a subject-specific three-dimensional linkage model configured by stance phase gait data and driven by one unit of muscle force. Eight healthy adult subjects were examined in gait analysis. The subtalar inversion/eversion was modeled by offsetting up to 20° from the normal subtalar angle while other configurations remained unaltered. This study showed that the gastrocnemius, soleus and tibialis anterior generally functioned as their anatomical definition in normal gait, but counterintuitive function was occasionally found in the bi-articular gastrocnemius. The plantarflexors play important roles in the body support and forward progression. Excessive subtalar eversion was found to enlarge the plantarflexors and tibialis anterior's function. Induced acceleration analysis demonstrated its ability to isolate the contributions of individual muscle to a given factor, and as a means of studying effect of pathological gait on the dynamic muscle functions. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Adherence to an (n-3) Fatty Acid/Fish Intake Pattern Is Inversely Associated with Metabolic Syndrome among Puerto Rican Adults in the Greater Boston Area123

    PubMed Central

    Noel, Sabrina E.; Newby, P. K.; Ordovas, Jose M.; Tucker, Katherine L.

    2010-01-01

    Combinations of fatty acids may affect risk of metabolic syndrome. Puerto Ricans have a disproportionate number of chronic conditions compared with other Hispanic groups. We aimed to characterize fatty acid intake patterns of Puerto Rican adults aged 45–75 y and living in the Greater Boston area (n = 1207) and to examine associations between these patterns and metabolic syndrome. Dietary fatty acids, as a percentage of total fat, were entered into principle components analysis. Spearman correlation coefficients were used to examine associations between fatty acid intake patterns, nutrients, and food groups. Associations with metabolic syndrome were analyzed by using logistic regression and general linear models with quintiles of principal component scores. Four principal components (factors) emerged: factor 1, short- and medium-chain SFA/dairy; factor 2, (n-3) fatty acid/fish; factor 3, very long-chain (VLC) SFA and PUFA/oils; and factor 4, monounsaturated fatty acid/trans fat. The SFA/dairy factor was inversely associated with fasting serum glucose concentrations (P = 0.02) and the VLC SFA/oils factor was negatively related to waist circumference (P = 0.008). However, these associations were no longer significant after additional adjustment for BMI. The (n-3) fatty acid/fish factor was associated with a lower likelihood of metabolic syndrome (Q5 vs. Q1: odds ratio: 0.54, 95% CI: 0.34, 0.86). In summary, principal components analysis of fatty acid intakes revealed 4 dietary fatty acid patterns in this population. Identifying optimal combinations of fatty acids may be beneficial for understanding relationships with health outcomes given their diverse effects on metabolism. PMID:20702744

  18. Inverse Thermal Analysis of Titanium GTA Welds Using Multiple Constraints

    NASA Astrophysics Data System (ADS)

    Lambrakos, S. G.; Shabaev, A.; Huang, L.

    2015-06-01

    Inverse thermal analysis of titanium gas-tungsten-arc welds using multiple constraint conditions is presented. This analysis employs a methodology that is in terms of numerical-analytical basis functions for inverse thermal analysis of steady-state energy deposition in plate structures. The results of this type of analysis provide parametric representations of weld temperature histories that can be adopted as input data to various types of computational procedures, such as those for prediction of solid-state phase transformations. In addition, these temperature histories can be used to construct parametric function representations for inverse thermal analysis of welds corresponding to other process parameters or welding processes whose process conditions are within similar regimes. The present study applies an inverse thermal analysis procedure that provides for the inclusion of constraint conditions associated with both solidification and phase transformation boundaries.

  19. Accommodating Chromosome Inversions in Linkage Analysis

    PubMed Central

    Chen, Gary K.; Slaten, Erin; Ophoff, Roel A.; Lange, Kenneth

    2006-01-01

    This work develops a population-genetics model for polymorphic chromosome inversions. The model precisely describes how an inversion changes the nature of and approach to linkage equilibrium. The work also describes algorithms and software for allele-frequency estimation and linkage analysis in the presence of an inversion. The linkage algorithms implemented in the software package Mendel estimate recombination parameters and calculate the posterior probability that each pedigree member carries the inversion. Application of Mendel to eight Centre d'Étude du Polymorphisme Humain pedigrees in a region containing a common inversion on 8p23 illustrates its potential for providing more-precise estimates of the location of an unmapped marker or trait gene. Our expanded cytogenetic analysis of these families further identifies inversion carriers and increases the evidence of linkage. PMID:16826515

  20. Trace lithium is inversely associated with male suicide after adjustment of climatic factors.

    PubMed

    Shiotsuki, Ippei; Terao, Takeshi; Ishii, Nobuyoshi; Takeuchi, Shouhei; Kuroda, Yoshiki; Kohno, Kentaro; Mizokami, Yoshinori; Hatano, Koji; Tanabe, Sanshi; Kanehisa, Masayuki; Iwata, Noboru; Matusda, Shinya

    2016-01-01

    Previously, we showed the inverse association between lithium in drinking water and male suicide in Kyushu Island. The narrow variation in meteorological factors of Kyushu Island and a considerable amount of evidence regarding the role of the factors on suicide provoked the necessities of adjusting the association by the wide variation in sunshine, temperature, rain fall, and snow fall. To keep the wide variation in meteorological factors, we combined the data of Kyushu (the southernmost city is Itoman, 26°) and Hokkaido (the northernmost city is Wakkanai, 45°). Multiple regression analyses were used to predict suicide SMRs (total, male and female) by lithium levels in drinking water and meteorological factors. After adjustment of meteorological factors, lithium levels were significantly and inversely associated with male suicide SMRs, but not with total or female suicide SMRs, across the 153 cities of Hokkaido and Kyushu Islands. Moreover, annual total sunshine and annual mean temperature were significantly and inversely associated with male suicide SMRs whereas annual total rainfall was significantly and directly associated with male suicide SMRs. The limitations of the present study include the lack of data relevant to lithium levels in food and the proportion of the population who drank tap water and their consumption habits. The present findings suggest that trace lithium is inversely associated with male but not female suicide after adjustment of meteorological factors. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. The association of educational attainment and SBP among older community-living adults: the Maintenance of Balance, Independent Living, Intellect and Zest in the Elderly (MOBILIZE) Boston Study

    PubMed Central

    Kiely, Dan K.; Gross, Alden L.; Kim, Dae H.; Lipsitz, Lewis A.

    2012-01-01

    Objective Educational attainment is inversely associated with SBP level in young adulthood. This association has not been studied in an older cohort, and confounding and mediating factors are not well known. Methods The authors hypothesized that higher education is associated with lower levels of SBP independent of many risk factors for hypertension. This prospective observational study included a sample of 764 older community-living participants in the Maintenance of Balance, Independent Living, Intellect and Zest in the Elderly (MOBILIZE) Boston Study. Results Compared to participants with more than college education, regression analyses showed those with a high school education or less had a SBP value 6.33 mmHg higher [95% confidence interval (CI): 2.55–10.10], and those who had a college education had a SBP value 4.01 mmHg higher (95% CI: 0.77–7.25) independent of many hypothesized confounders and mediators. Discussion Results of a path analysis confirmed that higher level of education was associated with lower SBP even after adjustment for hypothesized mediators. Although slightly attenuated by multivariable adjustment for hypertension risk factors, the significant inverse association between educational attainment and SBP was not entirely mediated by these risk factors. These findings indicate that education is inversely associated with SBP in a diverse cohort of community-living older adults, independent of many known or suspected risk factors. Conclusion This study is the first to report the association between education and SBP in an older sample, representing a population at the highest risk for hypertension-related morbidity and mortality. PMID:22688267

  2. The tobacco paradox in acute coronary syndrome. The prior cessation of smoking as a marker of a better short-term prognosis.

    PubMed

    Bastos-Amador, P; Almendro-Delia, M; Muñoz-Calero, B; Blanco-Ponce, E; Recio-Mayoral, A; Reina-Toral, A; Cruz-Fernandez, J M; García-Alcántara, A; Hidalgo-Urbano, R; García-Rubira, J C

    2016-01-01

    The tobacco paradox is a phenomenon insufficiently explained by previous studies. This study analyses the prognostic role of prior or active smoking in patients with acute coronary syndrome. We obtained data from the ARIAM registry, between 2001 and 2012. The study included 42,827 patients with acute coronary syndrome (mean age, 65±13 years; 26.4% women). The influence of smoking and that of being an ex-smoker on mortality was analysed using a multivariate analysis. The smokers were younger, were more often men, had less diabetes, hypertension and prior history of heart failure, stroke, arrhythmia and renal failure and more frequently had ST-elevation and a family history of smoking. The ex-smokers had more dyslipidaemia and history of angina, myocardial infarction, ischemic heart disease, peripheral vasculopathy and chronic bronchial disease. Smokers and ex-smokers less frequently developed cardiogenic shock (smokers 4.2%, ex-smokers 4.7% and nonsmokers 6.9%, P<.001). Hospital mortality was 7.8% for the nonsmokers, 4.9% for the ex-smokers and 3.1% for the smokers (P<.001). In the multivariate analysis, the smoker factor lost its influence in the prognosis (-0.26%, p=.52 using an inverse probability calculation; and+0.26%, P=.691 using a propensity analysis). However, the exsmoker factor showed a significant reduction in mortality in both tests (-2.4% in the inverse probability analysis, P<.001; and -1.5% in the propensity analysis, P=.005). The tobacco paradox is a finding that could be explained by other prognostic factors. Smoking cessation prior to hospitalization for acute coronary syndrome is associated with a better prognosis. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Medicina Interna (SEMI). All rights reserved.

  3. A chromosome 10 variant with a 12 Mb inversion [inv(10)(q11.22q21.1)] identical by descent and frequent in the Swedish population.

    PubMed

    Entesarian, Miriam; Carlsson, Birgit; Mansouri, Mahmoud Reza; Stattin, Eva-Lena; Holmberg, Eva; Golovleva, Irina; Stefansson, Hreinn; Klar, Joakim; Dahl, Niklas

    2009-03-01

    We identified a paracentric inversion of chromosome 10 [inv(10)(q11.22q21.1)] in 0.20% of Swedish individuals (15/7,439) referred for cytogenetic analysis. A retrospective analysis of 8,896 karyotypes from amniocenteses in Sweden revealed a carrier frequency of 0.079% (7/8,896) for the inversion. Cloning and detailed analysis of the inversion breakpoint regions show enrichment for interspersed repeat elements and AT-stretches. The centromeric breakpoint coincides with that of a predicted inversion from HapMap data, which suggests that this region is involved in several chromosome 10 variants. No known gene or predicted transcript are disrupted by the inversion which spans approximately 12 Mb. Carriers from four non-related Swedish families have identical inversion breakpoints and haplotype analysis confirmed that the rearrangement is identical by descent. Diagnosis was retrieved in 6 out of the 15 carriers referred for cytogenetic analysis. No consistent phenotype was found to be associated with the inversion. Our study demonstrates that the inv(10)(q11.22q21.1) is a rare and inherited chromosome variant with a broad geographical distribution in Sweden. 2009 Wiley-Liss, Inc.

  4. Age and gender might influence big five factors of personality: a preliminary report in Indian population.

    PubMed

    Magan, Dipti; Mehta, Manju; Sarvottam, Kumar; Yadav, Raj Kumar; Pandey, R M

    2014-01-01

    Age and gender are two important physiological variables which might influence the personality of an individual. The influence of age and gender on big five personality domains in Indian population was assessed in this cross-sectional study that included 155 subjects (female = 76, male = 79) aged from 16-75 years. Big five personality factors were evaluated using 60-item NEO-Five Factor Inventory (NEO-FFI) at a single point in time. Among the big five factors of personality, Conscientiousness was positively correlated (r = 0.195; P < 0.05) with age in total study population, and retained the significance (P < 0.05) in men only when analyzed by gender subgroups. Further, age and gender sub-group analysis also showed that Neuroticism was inversely correlated with age in women aged 26-35 years (P < 0.05). Neuroticism and Extraversion showed a positive correlation with age in men aged 36-45 years (P < 0.001 and P < 0.05, respectively). Neuroticism was inversely correlated with age in men aged 46-55 years (P < 0.05). This preliminary report suggested that personality traits might change with age, and is gender-dependent.

  5. A Synthetic Study on the Resolution of 2D Elastic Full Waveform Inversion

    NASA Astrophysics Data System (ADS)

    Cui, C.; Wang, Y.

    2017-12-01

    Gradient based full waveform inversion is an effective method in seismic study, it makes full use of the information given by seismic records and is capable of providing a more accurate model of the interior of the earth at a relatively low computational cost. However, the strong non-linearity of the problem brings about many difficulties in the assessment of its resolution. Synthetic inversions are therefore helpful before an inversion based on real data is made. Checker-board test is a commonly used method, but it is not always reliable due to the significant difference between a checker-board and the true model. Our study aims to provide a basic understanding of the resolution of 2D elastic inversion by examining three main factors that affect the inversion result respectively: 1. The structural characteristic of the model; 2. The level of similarity between the initial model and the true model; 3. The spacial distribution of sources and receivers. We performed about 150 synthetic inversions to demonstrate how each factor contributes to quality of the result, and compared the inversion results with those achieved by checker-board tests. The study can be a useful reference to assess the resolution of an inversion in addition to regular checker-board tests, or to determine whether the seismic data of a specific region is sufficient for a successful inversion.

  6. Sizing the association between lifestyle behaviours and fatness in a large, heterogeneous sample of youth of multiple ethnicities from 4 countries.

    PubMed

    Sluyter, John D; Scragg, Robert K R; Plank, Lindsay D; Waqa, Gade D; Fotu, Kalesita F; Swinburn, Boyd A

    2013-10-12

    The magnitude of the relationship between lifestyle risk factors for obesity and adiposity is not clear. The aim of this study was to clarify this in order to determine the level of importance of lifestyle factors in obesity aetiology. A cross-sectional analysis was carried out on data on youth who were not trying to change weight (n = 5714), aged 12 to 22 years and from 8 ethnic groups living in New Zealand, Australia, Fiji and Tonga. Demographic and lifestyle data were measured by questionnaires. Fatness was measured by body mass index (BMI), BMI z-score and bioimpedance analysis, which was used to estimate percent body fat and total fat mass (TFM). Associations between lifestyle and body composition variables were examined using linear regression and forest plots. TV watching was positively related to fatness in a dose-dependent manner. Strong, dose-dependent associations were observed between fatness and soft drink consumption (positive relationship), breakfast consumption (inverse relationship) and after-school physical activity (inverse relationship). Breakfast consumption-fatness associations varied in size across ethnic groups. Lifestyle risk factors for obesity were associated with percentage differences in body composition variables that were greatest for TFM and smallest for BMI. Lifestyle factors were most strongly related to TFM, which suggests that studies that use BMI alone to quantify fatness underestimate the full effect of lifestyle on adiposity. This study clarifies the size of lifestyle-fatness relationships observed in previous studies.

  7. Spatial and seasonal characteristics of cold-air pools in the upper Zêzere valley (Serra da Estrela, Portugal)

    NASA Astrophysics Data System (ADS)

    Mora, Carla

    2010-05-01

    Occurrence, formation, spatial patterns and intensity of cold air pools/lakes were studied in the Serra da Estrela (40° 20'N 7° 35'W, 1993m, Central Portugal) from January to December 2000. Data was collected using a network of air temperature dataloggers installed at different topographic positions (interfluves, valley floors and slopes) recording at 2-h intervals. A k-means classification was applied to the dataset of instantaneous air temperatures, and 3 types of thermal patterns were identified. Type 1 (66% cases) shows events with decreasing air temperatures with altitude. Type 2 (27% cases) shows accumulation of cold air in the valleys with higher valley floors showing the lowest temperatures. Type 3 (7% cases) show accumulation of cold air, but with lowest air temperatures in the valleys at lower altitudes. Causal factors for the occurrence of the patterns were studied by applying discriminant analysis on meteorological and topographical variables. Type 1 occurs under atmospheric instability conditions, while types 2 and 3 relate to atmospheric stability. Types 2 and 3 are controlled by seasonality and local insolation/shadowing effects. For the detailed study of cold air accumulations, two approaches were followed: the analysis of temperature differences between a station in a crest and a station in a glacial cirque floor; and, the analysis of 5-min interval temperature data along a transect in the Zêzere valley.The differences in air temperature between the glacier cirque floor (Covão Cimeiro, 1620m) and the crest (Cântaro Gordo, 1870m) were classified into 9 types of regime. Thermal inversions in the cirque were found in 6 types (48%). These are characterized in detail and the geographical and meteorological controlling factors are analyzed using one-way ANOVA and discriminant analysis. The 6 types show different daily regimes and inversion intensities, as well as a seasonal trend. The maximum inversion intensity was 9 °C, and the minimum temperature -17 °C at the cirque floor. Simultaneoulsy, the ridge showed -9 °C. Thermal inversions show atmospheric stability with low wind speed and low cloudiness. The sequence of patterns throughout the year is controlled by topographic factors and insolation at the cirque floor. The formation of thermal inversions in a NNE-SSW direction valley (Zêzere valley), their durationand dissipation were studied in detail during 5 days of atmospheric stability using air temperature recorded at 5-min intervals. During the day, air temperature decreased with altitude (-0.7 °C/100m to -1 °C/100m), and during the night, the valley floor showed lower temperatures than the mountain summit. During the night a thermal belt formed and the valley floor was 3 °C colder than the top of the inversion layer. During the day there was an asymmetry in the distribution of temperatures along the valley controlled by solar radiation. Air temperatures ranged from -5 °C to 16 °C. The results show the effect of topography on air temperatures in situations of atmospheric stability and can be extrapolated to the mountains with similar climatic and topographic conditions. The identification of the shadowing effect induced by valleys and its impact on the maintenance of cold air lakes during the morning in the valleys of North-South orientation can be of special interest for planning and environmental impact studies.

  8. The whole space three-dimensional magnetotelluric inversion algorithm with static shift correction

    NASA Astrophysics Data System (ADS)

    Zhang, K.

    2016-12-01

    Base on the previous studies on the static shift correction and 3D inversion algorithms, we improve the NLCG 3D inversion method and propose a new static shift correction method which work in the inversion. The static shift correction method is based on the 3D theory and real data. The static shift can be detected by the quantitative analysis of apparent parameters (apparent resistivity and impedance phase) of MT in high frequency range, and completed correction with inversion. The method is an automatic processing technology of computer with 0 cost, and avoids the additional field work and indoor processing with good results.The 3D inversion algorithm is improved (Zhang et al., 2013) base on the NLCG method of Newman & Alumbaugh (2000) and Rodi & Mackie (2001). For the algorithm, we added the parallel structure, improved the computational efficiency, reduced the memory of computer and added the topographic and marine factors. So the 3D inversion could work in general PC with high efficiency and accuracy. And all the MT data of surface stations, seabed stations and underground stations can be used in the inversion algorithm. The verification and application example of 3D inversion algorithm is shown in Figure 1. From the comparison of figure 1, the inversion model can reflect all the abnormal bodies and terrain clearly regardless of what type of data (impedance/tipper/impedance and tipper). And the resolution of the bodies' boundary can be improved by using tipper data. The algorithm is very effective for terrain inversion. So it is very useful for the study of continental shelf with continuous exploration of land, marine and underground.The three-dimensional electrical model of the ore zone reflects the basic information of stratum, rock and structure. Although it cannot indicate the ore body position directly, the important clues are provided for prospecting work by the delineation of diorite pluton uplift range. The test results show that, the high quality of the data processing and efficient inversion method for electromagnetic method is an important guarantee for porphyry ore.

  9. FAST: a framework for simulation and analysis of large-scale protein-silicon biosensor circuits.

    PubMed

    Gu, Ming; Chakrabartty, Shantanu

    2013-08-01

    This paper presents a computer aided design (CAD) framework for verification and reliability analysis of protein-silicon hybrid circuits used in biosensors. It is envisioned that similar to integrated circuit (IC) CAD design tools, the proposed framework will be useful for system level optimization of biosensors and for discovery of new sensing modalities without resorting to laborious fabrication and experimental procedures. The framework referred to as FAST analyzes protein-based circuits by solving inverse problems involving stochastic functional elements that admit non-linear relationships between different circuit variables. In this regard, FAST uses a factor-graph netlist as a user interface and solving the inverse problem entails passing messages/signals between the internal nodes of the netlist. Stochastic analysis techniques like density evolution are used to understand the dynamics of the circuit and estimate the reliability of the solution. As an example, we present a complete design flow using FAST for synthesis, analysis and verification of our previously reported conductometric immunoassay that uses antibody-based circuits to implement forward error-correction (FEC).

  10. Associations between dietary patterns, socio-demographic factors and anthropometric measurements in adult New Zealanders: an analysis of data from the 2008/09 New Zealand Adult Nutrition Survey.

    PubMed

    Beck, K L; Jones, B; Ullah, I; McNaughton, S A; Haslett, S J; Stonehouse, W

    2018-06-01

    To investigate associations between dietary patterns, socio-demographic factors and anthropometric measurements in adult New Zealanders. Dietary patterns were identified using factor analysis in adults 15 years plus (n = 4657) using 24-h diet recall data from the 2008/09 New Zealand Adult Nutrition Survey. Multivariate regression was used to investigate associations between dietary patterns and age, gender and ethnicity. After controlling for demographic factors, associations between dietary patterns and food insecurity, deprivation, education, and smoking were investigated. Associations between dietary patterns and body mass index and waist circumference were examined adjusting for demographic factors, smoking and energy intake. Two dietary patterns were identified. 'Healthy' was characterised by breakfast cereal, low fat milk, soy and rice milk, soup and stock, yoghurt, bananas, apples, other fruit and tea, and low intakes of pies and pastries, potato chips, white bread, takeaway foods, soft drinks, beer and wine. 'Traditional' was characterised by beef, starchy vegetables, green vegetables, carrots, tomatoes, savoury sauces, regular milk, cream, sugar, tea and coffee, and was low in takeaway foods. The 'healthy' pattern was positively associated with age, female gender, New Zealand European or other ethnicity, and a secondary school qualification, and inversely associated with smoking, food insecurity, area deprivation, BMI and waist circumference. The 'traditional' pattern was positively associated with age, male gender, smoking, food insecurity and inversely associated with a secondary school qualification. A 'Healthy' dietary pattern was associated with higher socio-economic status and reduced adiposity, while the 'traditional' pattern was associated with lower socio-economic status.

  11. Structural studies unravel the active conformation of apo RORγt nuclear receptor and a common inverse agonism of two diverse classes of RORγt inhibitors.

    PubMed

    Li, Xiang; Anderson, Marie; Collin, Delphine; Muegge, Ingo; Wan, John; Brennan, Debra; Kugler, Stanley; Terenzio, Donna; Kennedy, Charles; Lin, Siqi; Labadia, Mark E; Cook, Brian; Hughes, Robert; Farrow, Neil A

    2017-07-14

    The nuclear receptor retinoid acid receptor-related orphan receptor γt (RORγt) is a master regulator of the Th17/IL-17 pathway that plays crucial roles in the pathogenesis of autoimmunity. RORγt has recently emerged as a highly promising target for treatment of a number of autoimmune diseases. Through high-throughput screening, we previously identified several classes of inverse agonists for RORγt. Here, we report the crystal structures for the ligand-binding domain of RORγt in both apo and ligand-bound states. We show that apo RORγt adopts an active conformation capable of recruiting coactivator peptides and present a detailed analysis of the structural determinants that stabilize helix 12 (H12) of RORγt in the active state in the absence of a ligand. The structures of ligand-bound RORγt reveal that binding of the inverse agonists disrupts critical interactions that stabilize H12. This destabilizing effect is supported by ab initio calculations and experimentally by a normalized crystallographic B-factor analysis. Of note, the H12 destabilization in the active state shifts the conformational equilibrium of RORγt toward an inactive state, which underlies the molecular mechanism of action for the inverse agonists reported here. Our findings highlight that nuclear receptor structure and function are dictated by a dynamic conformational equilibrium and that subtle changes in ligand structures can shift this equilibrium in opposite directions, leading to a functional switch from agonists to inverse agonists. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Development of an inverse heat conduction model and its application to determination of heat transfer coefficient during casting solidification

    NASA Astrophysics Data System (ADS)

    Zhang, Liqiang; Reilly, Carl; Li, Luoxing; Cockcroft, Steve; Yao, Lu

    2014-07-01

    The interfacial heat transfer coefficient (IHTC) is required for the accurate simulation of heat transfer in castings especially for near net-shape processes. The large number of factors influencing heat transfer renders quantification by theoretical means a challenge. Likewise experimental methods applied directly to temperature data collected from castings are also a challenge to interpret because of the transient nature of many casting processes. Inverse methods offer a solution and have been applied successfully to predict the IHTC in many cases. However, most inverse approaches thus far focus on use of in-mold temperature data, which may be a challenge to obtain in cases where the molds are water-cooled. Methods based on temperature data from the casting have the potential to be used however; the latent heat released during the solidification of the molten metal complicates the associated IHTC calculations. Furthermore, there are limits on the maximum distance the thermocouples can be placed from the interface under analysis. An inverse conduction based method have been developed, verified and applied successfully to temperature data collected from within an aluminum casting in proximity to the mold. A modified specific heat method was used to account for latent heat evolution in which the rate of change of fraction solid with temperature was held constant. An analysis conducted with the inverse model suggests that the thermocouples must be placed no more than 2 mm from the interface. The IHTC values calculated for an aluminum alloy casting were shown to vary from 1,200 to 6,200 Wm-2 K-1. Additionally, the characteristics of the time-varying IHTC have also been discussed.

  13. The association of solar ultraviolet B (UVB) with reducing risk of cancer: multifactorial ecologic analysis of geographic variation in age-adjusted cancer mortality rates.

    PubMed

    Grant, William B; Garland, Cedric F

    2006-01-01

    Solar ultraviolet B (UVB) irradiance and vitamin D are associated with reduced cancer mortality rates. However, the previous ecologic study of UVB and cancer mortality rates in the U.S. (Grant, 2002) did not include other risk factors in the analysis. An ecologic study was performed using age-adjusted annual mortality rates for Caucasian Americans for 1950-69 and 1970-94, along with state-averaged values for selected years for alcohol consumption, Hispanic heritage, lung cancer (as a proxy for smoking), poverty, degree of urbanization and UVB in multiple regression analyses. Models were developed that explained much of the variance in cancer mortality rates, with stronger correlations for the earlier period. Fifteen types of cancer were inversely-associated with UVB. In the earlier period, most of the associations of cancer death rates with alcohol consumption (nine), Hispanic heritage (six), the proxy for smoking (ten), urban residence (seven) and poverty (inverse for eight) agreed well with the literature. These results provide additional support for the hypothesis that solar UVB, through photosynthesis of vitamin D, is inversely-associated with cancer mortality rates, and that various other cancer risk-modifying factors do not detract from this link. It is thought that sun avoidance practices after 1980, along with improved cancer treatment, led to reduced associations in the latter period. The results regarding solar UVB should be studied further with additional observational and intervention studies of vitamin D indices and cancer incidence, mortality and survival rates.

  14. Estimating the Effect of Targeted Screening Strategies: An Application to Colonoscopy and Colorectal Cancer.

    PubMed

    Thomas, Duncan C

    2017-07-01

    Screening behavior depends on previous screening history and family members' behaviors, which can act as both confounders and intermediate variables on a causal pathway from screening to disease risk. Conventional analyses that adjust for these variables can lead to incorrect inferences about the causal effect of screening if high-risk individuals are more likely to be screened. Analyzing the data in a manner that treats screening as randomized conditional on covariates allows causal parameters to be estimated; inverse probability weighting based on propensity of exposure scores is one such method considered here. I simulated family data under plausible models for the underlying disease process and for screening behavior to assess the performance of alternative methods of analysis and whether a targeted screening approach based on individuals' risk factors would lead to a greater reduction in cancer incidence in the population than a uniform screening policy. Simulation results indicate that there can be a substantial underestimation of the effect of screening on subsequent cancer risk when using conventional analysis approaches, which is avoided by using inverse probability weighting. A large case-control study of colonoscopy and colorectal cancer from Germany shows a strong protective effect of screening, but inverse probability weighting makes this effect even stronger. Targeted screening approaches based on either fixed risk factors or family history yield somewhat greater reductions in cancer incidence with fewer screens needed to prevent one cancer than population-wide approaches, but the differences may not be large enough to justify the additional effort required. See video abstract at, http://links.lww.com/EDE/B207.

  15. Analysis of Tube Free Hydroforming using an Inverse Approach with FLD-based Adjustment of Process Parameters

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nguyen, Ba Nghiep; Johnson, Kenneth I.; Khaleel, Mohammad A.

    2003-04-01

    This paper employs an inverse approach (IA) formulation for the analysis of tubes under free hydroforming conditions. The IA formulation is derived from that of Guo et al. established for flat sheet hydroforming analysis using constant strain triangular membrane elements. At first, an incremental analysis of free hydroforming for a hot-dip galvanized (HG/Z140) DP600 tube is performed using the finite element Marc code. The deformed geometry obtained at the last converged increment is then used as the final configuration in the inverse analysis. This comparative study allows us to assess the predicting capability of the inverse analysis. The results willmore » be compared with the experimental values determined by Asnafi and Skogsgardh. After that, a procedure based on a forming limit diagram (FLD) is proposed to adjust the process parameters such as the axial feed and internal pressure. Finally, the adjustment process is illustrated through a re-analysis of the same tube using the inverse approach« less

  16. Estimation of near-surface shear-wave velocities and quality factors using multichannel analysis of surface-wave methods

    NASA Astrophysics Data System (ADS)

    Xia, Jianghai

    2014-04-01

    This overview article gives a picture of multichannel analysis of high-frequency surface (Rayleigh and Love) waves developed mainly by research scientists at the Kansas Geological Survey, the University of Kansas and China University of Geosciences (Wuhan) during the last eighteen years by discussing dispersion imaging techniques, inversion systems, and real-world examples. Shear (S)-wave velocities of near-surface materials can be derived from inverting the dispersive phase velocities of high-frequency surface waves. Multichannel analysis of surface waves—MASW used phase information of high-frequency Rayleigh waves recorded on vertical component geophones to determine near-surface S-wave velocities. The differences between MASW results and direct borehole measurements are approximately 15% or less and random. Studies show that inversion with higher modes and the fundamental mode simultaneously can increase model resolution and an investigation depth. Multichannel analysis of Love waves—MALW used phase information of high-frequency Love waves recorded on horizontal (perpendicular to the direction of wave propagation) component geophones to determine S-wave velocities of shallow materials. Because of independence of compressional (P)-wave velocity, the MALW method has some attractive advantages, such as 1) Love-wave dispersion curves are simpler than Rayleigh wave's; 2) dispersion images of Love-wave energy have a higher signal to noise ratio and more focused than those generated from Rayleigh waves; and 3) inversion of Love-wave dispersion curves is less dependent on initial models and more stable than Rayleigh waves.

  17. Personal and workplace psychosocial risk factors for carpal tunnel syndrome: a pooled study cohort.

    PubMed

    Harris-Adamson, Carisa; Eisen, Ellen A; Dale, Ann Marie; Evanoff, Bradley; Hegmann, Kurt T; Thiese, Matthew S; Kapellusch, Jay M; Garg, Arun; Burt, Susan; Bao, Stephen; Silverstein, Barbara; Gerr, Fred; Merlino, Linda; Rempel, David

    2013-08-01

    Between 2001 and 2010, six research groups conducted coordinated multiyear, prospective studies of carpal tunnel syndrome (CTS) incidence in US workers from various industries and collected detailed subject-level exposure information with follow-up symptom, physical examination, electrophysiological measures and job changes. This analysis of the pooled cohort examined the incidence of dominant-hand CTS in relation to demographic characteristics and estimated associations with occupational psychosocial factors and years worked, adjusting for confounding by personal risk factors. 3515 participants, without baseline CTS, were followed-up to 7 years. Case criteria included symptoms and an electrodiagnostic study consistent with CTS. Adjusted HRs were estimated in Cox proportional hazard models. Workplace biomechanical factors were collected but not evaluated in this analysis. Women were at elevated risk for CTS (HR=1.30; 95% CI 0.98 to 1.72), and the incidence of CTS increased linearly with both age and body mass index (BMI) over most of the observed range. High job strain increased risk (HR=1.86; 95% CI 1.11 to 3.14), and social support was protective (HR=0.54; 95% CI 0.31 to 0.95). There was an inverse relationship with years worked among recent hires with the highest incidence in the first 3.5 years of work (HR=3.08; 95% CI 1.55 to 6.12). Personal factors associated with an increased risk of developing CTS were BMI, age and being a woman. Workplace risk factors were high job strain, while social support was protective. The inverse relationship between CTS incidence and years worked among recent hires suggests the presence of a healthy worker survivor effect in the cohort.

  18. Personal and workplace psychosocial risk factors for carpal tunnel syndrome: a pooled study cohort

    PubMed Central

    Harris-Adamson, Carisa; Eisen, Ellen A; Dale, Ann Marie; Evanoff, Bradley; Hegmann, Kurt T; Thiese, Matthew S; Kapellusch, Jay M; Garg, Arun; Burt, Susan; Bao, Stephen; Silverstein, Barbara; Gerr, Fred; Merlino, Linda; Rempel, David

    2015-01-01

    Background Between 2001 and 2010, six research groups conducted coordinated multiyear, prospective studies of carpal tunnel syndrome (CTS) incidence in US workers from various industries and collected detailed subject-level exposure information with follow-up symptom, physical examination, electrophysiological measures and job changes. Objective This analysis of the pooled cohort examined the incidence of dominant-hand CTS in relation to demographic characteristics and estimated associations with occupational psychosocial factors and years worked, adjusting for confounding by personal risk factors. Methods 3515 participants, without baseline CTS, were followed-up to 7 years. Case criteria included symptoms and an electrodiagnostic study consistent with CTS. Adjusted HRs were estimated in Cox proportional hazard models. Workplace biomechanical factors were collected but not evaluated in this analysis. Results Women were at elevated risk for CTS (HR=1.30; 95% CI 0.98 to 1.72), and the incidence of CTS increased linearly with both age and body mass index (BMI) over most of the observed range. High job strain increased risk (HR=1.86; 95% CI 1.11 to 3.14), and social support was protective (HR=0.54; 95% CI 0.31 to 0.95). There was an inverse relationship with years worked among recent hires with the highest incidence in the first 3.5 years of work (HR=3.08; 95% CI 1.55 to 6.12). Conclusions Personal factors associated with an increased risk of developing CTS were BMI, age and being a woman. Workplace risk factors were high job strain, while social support was protective. The inverse relationship between CTS incidence and years worked among recent hires suggests the presence of a healthy worker survivor effect in the cohort. PMID:23645610

  19. [Life satisfaction and related socio-demographic factors during female midlife].

    PubMed

    Cuadros, José Luis; Pérez-Roncero, Gonzalo R; López-Baena, María Teresa; Cuadros-Celorrio, Angela M; Fernández-Alonso, Ana María

    2014-01-01

    To assess life satisfaction and related factors in middle-aged Spanish women. This was a cross-sectional study including 235 women aged 40 to 65, living in Granada (Spain), healthy companions of patients visiting the obstetrics and gynecology clinics. They completed the Diener Satisfaction with Life Scale, the Menopause Rating Scale, the Perceived Stress Scale, the Insomnia Severity Index and a sociodemographic questionnaire containing personal and partner data. Internal consistency of each tool was also calculated. Almost two-thirds (61.3%) of the women were postmenopausal, and 43.8% had abdominal obesity, 36.6% had insomnia, 18.7% had poor menopause-related quality of life, 31.9% performed regular exercise, and 5.1% had severe financial problems. Life satisfaction showed significant positive correlations (Spearman's test) with female and male age, and inverse correlations with menopause-related quality of life, perceived stress and insomnia. In the multiple linear regression analysis, high life satisfaction is positively correlated with having a partner who performed exercise, and inversely with having work problems, perceived stress and the suspicion of partner infidelity. These factors explained 40% of the variance of the multiple regression analysis for life satisfaction in middle-aged women. Life satisfaction is a construct related to perceived stress, work problems, and having a partner, while aspects of menopause and general health had no significant influence. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  20. [Family paracentric inversion of the short arm of chromosome X (Xp21.2p11.23) and connection with autism spectrum disorders].

    PubMed

    Milovančević, Milica Pejović; Vešić, Marija; Jelisavčić, Marko; Nikšić, Snežana; Pilić, Gordana Radivojević; Maravić, Vanja Mandić

    2012-01-01

    Autism spectrum disorders (ASDs) are a group of complex pervasive developmental disorders characterized by impairments in communication, social interaction and behavior. In most cases autism is caused by a combination of genetic factors and environmental risk factors. In 10% to 20% of cases it has been shown that the cause of ASD is genetic. We are describing a 2-year-old boy who was referred to genetic counseling because of speech delay and certain autism-like behavior. By cytogenetic analysis the karyotype 46, inv(X),Y was obtained. The boy was a carrier of a paracentric inversion of the short arm of the chromosome X. After cytogenetic analysis of parental blood, it was detected that mother was a carrier of identical aberration, but had no clinical signs. The method of fluorescent in situ hybridization (FISH) yielded the precise breakpoint in the region (p21.2p11.23). Mother and son were carriers of identical X chromosome. Breakpoints are located in the regions that have already been linked to autism, which indicates that the positional effect of the gene could have been a possible cause of the patient's genotype. In addition to positional effects, in order to better understand the etiology of autism other genetic and environmental factors should be always taken into consideration.

  1. [Baseline correction of spectrum for the inversion of chlorophyll-a concentration in the turbidity water].

    PubMed

    Wei, Yu-Chun; Wang, Guo-Xiang; Cheng, Chun-Mei; Zhang, Jing; Sun, Xiao-Peng

    2012-09-01

    Suspended particle material is the main factor affecting remote sensing inversion of chlorophyll-a concentration (Chla) in turbidity water. According to the optical property of suspended material in water, the present paper proposed a linear baseline correction method to weaken the suspended particle contribution in the spectrum above turbidity water surface. The linear baseline was defined as the connecting line of reflectance from 450 to 750 nm, and baseline correction is that spectrum reflectance subtracts the baseline. Analysis result of field data in situ of Meiliangwan, Taihu Lake in April, 2011 and March, 2010 shows that spectrum linear baseline correction can improve the inversion precision of Chl a and produce the better model diagnoses. As the data in March, 2010, RMSE of band ratio model built by original spectrum is 4.11 mg x m(-3), and that built by spectrum baseline correction is 3.58 mg x m(-3). Meanwhile, residual distribution and homoscedasticity in the model built by baseline correction spectrum is improved obviously. The model RMSE of April, 2011 shows the similar result. The authors suggest that using linear baseline correction as the spectrum processing method to improve Chla inversion accuracy in turbidity water without algae bloom.

  2. Analysis of space telescope data collection system

    NASA Technical Reports Server (NTRS)

    Ingels, F. M.; Schoggen, W. O.

    1982-01-01

    An analysis of the expected performance for the Multiple Access (MA) system is provided. The analysis covers the expected bit error rate performance, the effects of synchronization loss, the problem of self-interference, and the problem of phase ambiguity. The problem of false acceptance of a command word due to data inversion is discussed. A mathematical determination of the probability of accepting an erroneous command word due to a data inversion is presented. The problem is examined for three cases: (1) a data inversion only, (2) a data inversion and a random error within the same command word, and a block (up to 256 48-bit words) containing both a data inversion and a random error.

  3. Inverse Thermal Analysis of Alloy 690 Laser and Hybrid Laser-GMA Welds Using Solidification-Boundary Constraints

    NASA Astrophysics Data System (ADS)

    Lambrakos, S. G.

    2017-08-01

    An inverse thermal analysis of Alloy 690 laser and hybrid laser-GMA welds is presented that uses numerical-analytical basis functions and boundary constraints based on measured solidification cross sections. In particular, the inverse analysis procedure uses three-dimensional constraint conditions such that two-dimensional projections of calculated solidification boundaries are constrained to map within experimentally measured solidification cross sections. Temperature histories calculated by this analysis are input data for computational procedures that predict solid-state phase transformations and mechanical response. These temperature histories can be used for inverse thermal analysis of welds corresponding to other welding processes whose process conditions are within similar regimes.

  4. Influence of ankle joint plantarflexion and dorsiflexion on lateral ankle sprain: A computational study.

    PubMed

    Purevsuren, Tserenchimed; Kim, Kyungsoo; Batbaatar, Myagmarbayar; Lee, SuKyoung; Kim, Yoon Hyuk

    2018-05-01

    Understanding the mechanism of injury involved in lateral ankle sprain is essential to prevent injury, to establish surgical repair and reconstruction, and to plan reliable rehabilitation protocols. Most studies for lateral ankle sprain posit that ankle inversion, internal rotation, and plantarflexion are involved in the mechanism of injury. However, recent studies indicated that ankle dorsiflexion also plays an important role in the lateral ankle sprain mechanism. In this study, the contributions of ankle plantarflexion and dorsiflexion on the ankle joint were evaluated under complex combinations of internal and inversion moments. A multibody ankle joint model including 24 ligaments was developed and validated against two experimental cadaveric studies. The effects of ankle plantarflexion (up to 60°) and dorsiflexion (up to 30°) on the lateral ankle sprain mechanism under ankle inversion moment coupled with internal rotational moment were investigated using the validated model. Lateral ankle sprain injuries can occur during ankle dorsiflexion, in which the calcaneofibular ligament and anterior talofibular ligament tears may occur associated with excessive inversion and internal rotational moment, respectively. Various combinations of inversion and internal moment may lead to anterior talofibular ligament injuries at early ankle plantarflexion, while the inversion moment acts as a primary factor to tear the anterior talofibular ligament in early plantarflexion. It is better to consider inversion and internal rotation as primary factors of the lateral ankle sprain mechanism, while plantarflexion or dorsiflexion can be secondary factor. This information will help to clarify the lateral ankle sprain mechanism of injury.

  5. Factors Associated With Care Workers' Intention to Leave Employment in Nursing Homes: A Secondary Data Analysis of the Swiss Nursing Homes Human Resources Project.

    PubMed

    Gaudenz, Clergia; De Geest, Sabina; Schwendimann, René; Zúñiga, Franziska

    2017-07-01

    The emerging care personnel shortage in Swiss nursing homes is aggravated by high turnover rates. As intention to leave is a predictor of turnover, awareness of its associated factors is essential. This study applied a secondary data analysis to evaluate the prevalence and variability of 3,984 nursing home care workers' intention to leave. Work environment factors and care worker outcomes were tested via multiple regression analysis. Although 56% of care workers reported intention to leave, prevalences varied widely between facilities. Overall, intention to leave showed strong inverse relationships with supportive leadership and affective organizational commitment and weaker positive relationships with stress due to workload, emotional exhaustion, and care worker health problems. The strong direct relationship of nursing home care workers' intention to leave with affective organizational commitment and perceptions of leadership quality suggest that multilevel interventions to improve these factors might reduce intention to leave.

  6. Dietary patterns and risk of ductal carcinoma of the breast: a factor analysis in Uruguay.

    PubMed

    Ronco, Alvaro L; De Stefani, Eduardo; Deneo-Pellegrini, Hugo; Boffetta, Paolo; Aune, Dagfinn; Silva, Cecilia; Landó, Gabriel; Luaces, María E; Acosta, Gisele; Mendilaharsu, María

    2010-01-01

    Breast cancer (BC) shows very high incidence rates in Uruguayan women. The present factor analysis of ductal carcinoma of the breast, the most frequent histological type of this malignancy both in Uruguay and in the World, was conducted at a prepaid hospital of Montevideo, Uruguay. We identified 111 cases with ductal BC and 222 controls with normal mammograms. A factor analysis was conducted using 39 food groups, allowing retention of six factors analyzed through logistic regression in order to obtain odds ratios (OR) associated with ductal BC. The low fat and non-alcoholic beverage patterns were inversely associated (OR=0.30 and OR=0.45, respectively) with risk. Conversely, the fatty cheese pattern was positively associated (OR=4.17) as well as the fried white meat (OR=2.28) and Western patterns (OR 2.13). Ductal BC shared similar dietary risk patterns as those identified by studies not discriminating between histologic type of breast cancer.

  7. Effects of spatially variable resolution on field-scale estimates of tracer concentration from electrical inversions using Archie's law

    USGS Publications Warehouse

    Singha, Kamini; Gorelick, Steven M.

    2006-01-01

    Two important mechanisms affect our ability to estimate solute concentrations quantitatively from the inversion of field-scale electrical resistivity tomography (ERT) data: (1) the spatially variable physical processes that govern the flow of current as well as the variation of physical properties in space and (2) the overparameterization of inverse models, which requires the imposition of a smoothing constraint (regularization) to facilitate convergence of the inverse solution. Based on analyses of field and synthetic data, we find that the ability of ERT to recover the 3D shape and magnitudes of a migrating conductive target is spatially variable. Additionally, the application of Archie's law to tomograms from field ERT data produced solute concentrations that are consistently less than 10% of point measurements collected in the field and estimated from transport modeling. Estimates of concentration from ERT using Archie's law only fit measured solute concentrations if the apparent formation factor is varied with space and time and allowed to take on unreasonably high values. Our analysis suggests that the inability to find a single petrophysical relation in space and time between concentration and electrical resistivity is largely an effect of two properties of ERT surveys: (1) decreased sensitivity of ERT to detect the target plume with increasing distance from the electrodes and (2) the smoothing imprint of regularization used in inversion.

  8. Global Mapping of Oceanic and Continental Shelf Crustal Thickness and Ocean-Continent Transition Structure

    NASA Astrophysics Data System (ADS)

    Kusznir, Nick; Alvey, Andy; Roberts, Alan

    2017-04-01

    The 3D mapping of crustal thickness for continental shelves and oceanic crust, and the determination of ocean-continent transition (OCT) structure and continent-ocean boundary (COB) location, represents a substantial challenge. Geophysical inversion of satellite derived free-air gravity anomaly data incorporating a lithosphere thermal anomaly correction (Chappell & Kusznir, 2008) now provides a useful and reliable methodology for mapping crustal thickness in the marine domain. Using this we have produced the first comprehensive maps of global crustal thickness for oceanic and continental shelf regions. Maps of crustal thickness and continental lithosphere thinning factor from gravity inversion may be used to determine the distribution of oceanic lithosphere, micro-continents and oceanic plateaux including for the inaccessible polar regions (e.g. Arctic Ocean, Alvey et al.,2008). The gravity inversion method provides a prediction of continent-ocean boundary location which is independent of ocean magnetic anomaly and isochron interpretation. Using crustal thickness and continental lithosphere thinning factor maps with superimposed shaded-relief free-air gravity anomaly, we can improve the determination of pre-breakup rifted margin conjugacy and sea-floor spreading trajectory during ocean basin formation. By restoring crustal thickness & continental lithosphere thinning to their initial post-breakup configuration we show the geometry and segmentation of the rifted continental margins at their time of breakup, together with the location of highly-stretched failed breakup basins and rifted micro-continents. For detailed analysis to constrain OCT structure, margin type (i.e. magma poor, "normal" or magma rich) and COB location, a suite of quantitative analytical methods may be used which include: (i) Crustal cross-sections showing Moho depth and crustal basement thickness from gravity inversion. (ii) Residual depth anomaly (RDA) analysis which is used to investigate OCT bathymetric anomalies with respect to expected oceanic values. This includes flexural backstripping to produce bathymetry corrected for sediment loading. (iii) Subsidence analysis which is used to determine the distribution of continental lithosphere thinning. (iv) Joint inversion of time-domain deep seismic reflection and gravity anomaly data which is used to determine lateral variations in crustal basement density and velocity across the OCT, and to validate deep seismic reflection interpretations of Moho depth. The combined interpretation of these independent quantitative measurements is used to determine crustal thickness and composition across the ocean-continent-transition. This integrated approach has been validated on the Iberian margin where ODP drilling provides ground-truth of ocean-continent-transition crustal structure, continent-ocean-boundary location and magmatic type.

  9. Physical inactivity as a risk factor for primary and secondary coronary events in Göteborg, Sweden.

    PubMed

    Johansson, S; Rosengren, A; Tsipogianni, A; Ulvenstam, G; Wiklund, I; Wilhelmsen, L

    1988-11-01

    Physical activity at work and during leisure time were studied by using a questionnaire in a random sample of 7495 middle-aged men from the Primary Prevention Study in Göteborg and in 1273 able-bodied male patients with a first myocardial infarction, registered in the Infarction Register in the same city over the period 1968-84. Data on coronary risk factors and socio-economic factors were recorded in the population sample as were data on risk factors and known somatic predictors for prognosis in the infarction group. An inverse and graded association was found between leisure time physical activity and mean diastolic blood pressure, total cholesterol, body mass index, tobacco smoking, socio-economic status and mental stress in the random sample. During the approximate 12-year follow-up, low physical activity during leisure time, but not at work, was associated with an increased risk of coronary deaths and non-fatal infarctions in univariate analysis. Inactive subjects had twice the incidence of total coronary events (9.4%) as physically active contemporaries (4.2%). After controlling for major coronary risk factors, occupational class, diabetes, family history of coronary heart disease and mental stress in a multivariate logistic regression analysis, the association between leisure time physical activity and total coronary events disappeared. Physical activity at work and during leisure time estimated for the 12-month period preceding the first infarction was not associated with long-term prognosis after infarction. Infarction patients assessed to be in need of additional rehabilitation due to somatic restrictions, work-related factors and emotional instability, resumed work later and had a higher mortality and non-fatal recurrence rate during follow-up than patients not considered to require additional rehabilitation. Physical inactivity was not a risk factor for primary and secondary coronary events in this study. The inverse direction of the association between leisure time physical activity and coronary risk factors suggests that increased physical activity alters the risk factor profile in a favourable direction.

  10. Strategies to Enhance the Model Update in Regions of Weak Sensitivities for Use in Full Waveform Inversion

    NASA Astrophysics Data System (ADS)

    Nuber, André; Manukyan, Edgar; Maurer, Hansruedi

    2014-05-01

    Conventional methods of interpreting seismic data rely on filtering and processing limited portions of the recorded wavefield. Typically, either reflections, refractions or surface waves are considered in isolation. Particularly in near-surface engineering and environmental investigations (depths less than, say 100 m), these wave types often overlap in time and are difficult to separate. Full waveform inversion is a technique that seeks to exploit and interpret the full information content of the seismic records without the need for separating events first; it yields models of the subsurface at sub-wavelength resolution. We use a finite element modelling code to solve the 2D elastic isotropic wave equation in the frequency domain. This code is part of a Gauss-Newton inversion scheme which we employ to invert for the P- and S-wave velocities as well as for density in the subsurface. For shallow surface data the use of an elastic forward solver is essential because surface waves often dominate the seismograms. This leads to high sensitivities (partial derivatives contained in the Jacobian matrix of the Gauss-Newton inversion scheme) and thus large model updates close to the surface. Reflections from deeper structures may also include useful information, but the large sensitivities of the surface waves often preclude this information from being fully exploited. We have developed two methods that balance the sensitivity distributions and thus may help resolve the deeper structures. The first method includes equilibrating the columns of the Jacobian matrix prior to every inversion step by multiplying them with individual scaling factors. This is expected to also balance the model updates throughout the entire subsurface model. It can be shown that this procedure is mathematically equivalent to balancing the regularization weights of the individual model parameters. A proper choice of the scaling factors required to balance the Jacobian matrix is critical. We decided to normalise the columns of the Jacobian based on their absolute column sum, but defining an upper threshold for the scaling factors. This avoids particularly small and therefore insignificant sensitivities being over-boosted, which would produce unstable results. The second method proposed includes adjusting the inversion cell size with depth. Multiple cells of the forward modelling grid are merged to form larger inversion cells (typical ratios between forward and inversion cells are in the order of 1:100). The irregular inversion grid is adapted to the expected resolution power of full waveform inversion. Besides stabilizing the inversion, this approach also reduces the number of model parameters to be recovered. Consequently, the computational costs and the memory consumption are reduced significantly. This is particularly critical when Gauss-Newton type inversion schemes are employed. Extensive tests with synthetic data demonstrated that both methods stabilise the inversion and improve the inversion results. The two methods have some redundancy, which can be seen when both are applied simultaneously, that is, when scaling of the Jacobian matrix is applied to an irregular inversion grid. The calculated scaling factors are quite balanced and span a much smaller range than in the case of a regular inversion grid.

  11. Alcohol types and sociodemographic characteristics as risk factors for Barrett’s esophagus

    PubMed Central

    Kubo, Ai; Levin, T.R.; Block, Gladys; Rumore, Gregory; Quesenberry, Charles P.; Buffler, Patricia; Corley, Douglas A.

    2009-01-01

    Background & Aims Little is known about the effects of alcohol use and sociodemographics on the risk of Barrett’s esophagus, a precursor to esophageal adenocarcinoma. We evaluated the association between alcohol use, alcohol type, sociodemographic profiles, other lifestyle factors and the risk of Barrett’s esophagus. Methods Using a case-control study within the Kaiser Permanente Northern California membership, patients with a new diagnosis of Barrett’s esophagus (n=320) diagnosed between 2002–2005 were matched to persons with gastroesophageal reflux disease (GERD) (n=316) and to population controls (n=317). We collected information using validated questionnaires during direct in-person interviews. Analyses used multivariate unconditional logistic regression. Results Total alcohol use was not significantly associated with the risk of Barrett’s esophagus, although stratification by beverage type showed an inverse association for wine drinkers compared to nondrinkers (7+ drinks wine/week vs. none: OR=0.44, 95%CI (0.20–0.99); multivariate analysis). Among population controls, those who preferred wine were more likely to have college degrees and regularly take vitamin supplements than those who preferred beer or liquor, although adjustment for these factors or GERD symptoms did not eliminate the inverse association between wine consumption and Barrett’s esophagus. Education status was significantly inversely associated with the risk of Barrett’s esophagus. Conclusions There are associations between alcohol types, socioeconomic status and the risk of Barrett’s esophagus. Although choice of alcoholic beverages was associated with several factors, multiple adjustments (including for GERD) did not eliminate the association between alcohol and Barrett’s esophagus. Further research to evaluate the associations among socioeconomic status, GERD, and Barrett’s esophagus is warranted. PMID:19111726

  12. Survival analysis using inverse probability of treatment weighted methods based on the generalized propensity score.

    PubMed

    Sugihara, Masahiro

    2010-01-01

    In survival analysis, treatment effects are commonly evaluated based on survival curves and hazard ratios as causal treatment effects. In observational studies, these estimates may be biased due to confounding factors. The inverse probability of treatment weighted (IPTW) method based on the propensity score is one of the approaches utilized to adjust for confounding factors between binary treatment groups. As a generalization of this methodology, we developed an exact formula for an IPTW log-rank test based on the generalized propensity score for survival data. This makes it possible to compare the group differences of IPTW Kaplan-Meier estimators of survival curves using an IPTW log-rank test for multi-valued treatments. As causal treatment effects, the hazard ratio can be estimated using the IPTW approach. If the treatments correspond to ordered levels of a treatment, the proposed method can be easily extended to the analysis of treatment effect patterns with contrast statistics. In this paper, the proposed method is illustrated with data from the Kyushu Lipid Intervention Study (KLIS), which investigated the primary preventive effects of pravastatin on coronary heart disease (CHD). The results of the proposed method suggested that pravastatin treatment reduces the risk of CHD and that compliance to pravastatin treatment is important for the prevention of CHD. (c) 2009 John Wiley & Sons, Ltd.

  13. Molecular characterization and chromosomal distribution of Galileo, Kepler and Newton, three foldback transposable elements of the Drosophila buzzatii species complex.

    PubMed

    Casals, Ferran; Cáceres, Mario; Manfrin, Maura Helena; González, Josefa; Ruiz, Alfredo

    2005-04-01

    Galileo is a foldback transposable element that has been implicated in the generation of two polymorphic chromosomal inversions in Drosophila buzzatii. Analysis of the inversion breakpoints led to the discovery of two additional elements, called Kepler and Newton, sharing sequence and structural similarities with Galileo. Here, we describe in detail the molecular structure of these three elements, on the basis of the 13 copies found at the inversion breakpoints plus 10 additional copies isolated during this work. Similarly to the foldback elements described in other organisms, these elements have long inverted terminal repeats, which in the case of Galileo possess a complex structure and display a high degree of internal variability between copies. A phylogenetic tree built with their shared sequences shows that the three elements are closely related and diverged approximately 10 million years ago. We have also analyzed the abundance and chromosomal distribution of these elements in D. buzzatii and other species of the repleta group by Southern analysis and in situ hybridization. Overall, the results suggest that these foldback elements are present in all the buzzatti complex species and may have played an important role in shaping their genomes. In addition, we show that recombination rate is the main factor determining the chromosomal distribution of these elements.

  14. An exploratory risk perception study of attitudes toward homeland security systems.

    PubMed

    Sanquist, Thomas F; Mahy, Heidi; Morris, Frederic

    2008-08-01

    Understanding the issues surrounding public acceptance of homeland security systems is important for balancing security needs and potential civil liberties infringements. A psychometric survey was used in an exploratory study of attitudes regarding homeland security systems. Psychometric rating data were obtained from 182 respondents on psychological attributes associated with 12 distinct types of homeland security systems. An inverse relationship was observed for the overall rating attributes of acceptability and risk of civil liberties infringement. Principal components analysis (PCA) yielded a two-factor solution with the rating scale loading pattern suggesting factors of perceived effectiveness and perceived intrusiveness. These factors also showed an inverse relationship. The 12 different homeland security systems showed significantly different scores on the rating scales and PCA factors. Of the 12 systems studied, airport screening, canine detectors, and radiation monitoring at borders were found to be the most acceptable, while email monitoring, data mining, and global positioning satellite (GPS) tracking were found to be least acceptable. Students rated several systems as more effective than professionals, but the overall pattern of results for both types of subjects was similar. The data suggest that risk perception research and the psychometric paradigm are useful approaches for quantifying attitudes regarding homeland security systems and policies and can be used to anticipate potentially significant public acceptance issues.

  15. Recombination rate predicts inversion size in Diptera.

    PubMed Central

    Cáceres, M; Barbadilla, A; Ruiz, A

    1999-01-01

    Most species of the Drosophila genus and other Diptera are polymorphic for paracentric inversions. A common observation is that successful inversions are of intermediate size. We test here the hypothesis that the selected property is the recombination length of inversions, not their physical length. If so, physical length of successful inversions should be negatively correlated with recombination rate across species. This prediction was tested by a comprehensive statistical analysis of inversion size and recombination map length in 12 Diptera species for which appropriate data are available. We found that (1) there is a wide variation in recombination map length among species; (2) physical length of successful inversions varies greatly among species and is inversely correlated with the species recombination map length; and (3) neither the among-species variation in inversion length nor the correlation are observed in unsuccessful inversions. The clear differences between successful and unsuccessful inversions point to natural selection as the most likely explanation for our results. Presumably the selective advantage of an inversion increases with its length, but so does its detrimental effect on fertility due to double crossovers. Our analysis provides the strongest and most extensive evidence in favor of the notion that the adaptive value of inversions stems from their effect on recombination. PMID:10471710

  16. Comparison of adjoint and analytical Bayesian inversion methods for constraining Asian sources of carbon monoxide using satellite (MOPITT) measurements of CO columns

    NASA Astrophysics Data System (ADS)

    Kopacz, Monika; Jacob, Daniel J.; Henze, Daven K.; Heald, Colette L.; Streets, David G.; Zhang, Qiang

    2009-02-01

    We apply the adjoint of an atmospheric chemical transport model (GEOS-Chem CTM) to constrain Asian sources of carbon monoxide (CO) with 2° × 2.5° spatial resolution using Measurement of Pollution in the Troposphere (MOPITT) satellite observations of CO columns in February-April 2001. Results are compared to the more common analytical method for solving the same Bayesian inverse problem and applied to the same data set. The analytical method is more exact but because of computational limitations it can only constrain emissions over coarse regions. We find that the correction factors to the a priori CO emission inventory from the adjoint inversion are generally consistent with those of the analytical inversion when averaged over the large regions of the latter. The adjoint solution reveals fine-scale variability (cities, political boundaries) that the analytical inversion cannot resolve, for example, in the Indian subcontinent or between Korea and Japan, and some of that variability is of opposite sign which points to large aggregation errors in the analytical solution. Upward correction factors to Chinese emissions from the prior inventory are largest in central and eastern China, consistent with a recent bottom-up revision of that inventory, although the revised inventory also sees the need for upward corrections in southern China where the adjoint and analytical inversions call for downward correction. Correction factors for biomass burning emissions derived from the adjoint and analytical inversions are consistent with a recent bottom-up inventory on the basis of MODIS satellite fire data.

  17. Does sufficient evidence exist to support a causal association between vitamin D status and cardiovascular disease risk? An assessment using Hill's criteria for causality.

    PubMed

    Weyland, Patricia G; Grant, William B; Howie-Esquivel, Jill

    2014-09-02

    Serum 25-hydroxyvitamin D (25(OH)D) levels have been found to be inversely associated with both prevalent and incident cardiovascular disease (CVD) risk factors; dyslipidemia, hypertension and diabetes mellitus. This review looks for evidence of a causal association between low 25(OH)D levels and increased CVD risk. We evaluated journal articles in light of Hill's criteria for causality in a biological system. The results of our assessment are as follows. Strength of association: many randomized controlled trials (RCTs), prospective and cross-sectional studies found statistically significant inverse associations between 25(OH)D levels and CVD risk factors. Consistency of observed association: most studies found statistically significant inverse associations between 25(OH)D levels and CVD risk factors in various populations, locations and circumstances. Temporality of association: many RCTs and prospective studies found statistically significant inverse associations between 25(OH)D levels and CVD risk factors. Biological gradient (dose-response curve): most studies assessing 25(OH)D levels and CVD risk found an inverse association exhibiting a linear biological gradient. Plausibility of biology: several plausible cellular-level causative mechanisms and biological pathways may lead from a low 25(OH)D level to increased risk for CVD with mediators, such as dyslipidemia, hypertension and diabetes mellitus. Experimental evidence: some well-designed RCTs found increased CVD risk factors with decreasing 25(OH)D levels. Analogy: the association between serum 25(OH)D levels and CVD risk is analogous to that between 25(OH)D levels and the risk of overall cancer, periodontal disease, multiple sclerosis and breast cancer. all relevant Hill criteria for a causal association in a biological system are satisfied to indicate a low 25(OH)D level as a CVD risk factor.

  18. Objective function analysis for electric soundings (VES), transient electromagnetic soundings (TEM) and joint inversion VES/TEM

    NASA Astrophysics Data System (ADS)

    Bortolozo, Cassiano Antonio; Bokhonok, Oleg; Porsani, Jorge Luís; Monteiro dos Santos, Fernando Acácio; Diogo, Liliana Alcazar; Slob, Evert

    2017-11-01

    Ambiguities in geophysical inversion results are always present. How these ambiguities appear in most cases open to interpretation. It is interesting to investigate ambiguities with regard to the parameters of the models under study. Residual Function Dispersion Map (RFDM) can be used to differentiate between global ambiguities and local minima in the objective function. We apply RFDM to Vertical Electrical Sounding (VES) and TEM Sounding inversion results. Through topographic analysis of the objective function we evaluate the advantages and limitations of electrical sounding data compared with TEM sounding data, and the benefits of joint inversion in comparison with the individual methods. The RFDM analysis proved to be a very interesting tool for understanding the joint inversion method of VES/TEM. Also the advantage of the applicability of the RFDM analyses in real data is explored in this paper to demonstrate not only how the objective function of real data behaves but the applicability of the RFDM approach in real cases. With the analysis of the results, it is possible to understand how the joint inversion can reduce the ambiguity of the methods.

  19. Inverse expression of cystein-rich 61 (Cyr61/CCN1) and connective tissue growth factor (CTGF/CCN2) in borderline tumors and carcinomas of the ovary.

    PubMed

    Bartel, Frank; Balschun, Katharina; Gradhand, Elise; Strauss, Hans G; Dittmer, Jürgen; Hauptmann, Steffen

    2012-09-01

    Members of the CCN [cystein-rich 61 (Cyr61)/connective tissue growth factor (CTGF)/nephroblastoma (NOV)] protein family are involved in the regulation of cellular proliferation, apoptosis, and migration and are also assumed to play a role in carcinogenesis. Therefore, we performed a retrospective study to investigate the immunohistochemical expression of both Cyr61 and CTGF in 92 borderline tumors (BOTs) and 107 invasive carcinomas of the ovary (IOCs). To determine their diagnostic and prognostic value, we correlated protein expression with clinicopathologic factors including overall and disease-free survival. Cyr61 and CTGF were found to be inversely expressed in both BOTs and IOCs, with a stronger expression of Cyr61 in IOCs. Moreover, Cyr61 was found to be preferentially expressed in high-grade serous carcinomas, whereas CTGF was found more frequently in low-grade serous carcinomas. Weak Cyr61 levels correlated with both low estrogen receptor and p53 expression (P=0.038, P=0.04, respectively). However, no association was observed between CTGF, estrogen receptor, and p53 expression levels in IOCs. Regarding prognosis, Cyr61 was found to be of no value, but the loss of CTGF was found to be associated with a poor prognosis in multivariate analysis of overall (relative risk 2.8; P=0.050) and disease-free (relative risk 2.3; P=0.031) survival. Cyr61 and CTGF are inversely expressed in BOTs and IOCs, and loss of CTGF independently indicates poor prognosis in IOCs.

  20. A full potential inverse method based on a density linearization scheme for wing design

    NASA Technical Reports Server (NTRS)

    Shankar, V.

    1982-01-01

    A mixed analysis inverse procedure based on the full potential equation in conservation form was developed to recontour a given base wing to produce density linearization scheme in applying the pressure boundary condition in terms of the velocity potential. The FL030 finite volume analysis code was modified to include the inverse option. The new surface shape information, associated with the modified pressure boundary condition, is calculated at a constant span station based on a mass flux integration. The inverse method is shown to recover the original shape when the analysis pressure is not altered. Inverse calculations for weakening of a strong shock system and for a laminar flow control (LFC) pressure distribution are presented. Two methods for a trailing edge closure model are proposed for further study.

  1. Inverse Thermal Analysis of Ti-6Al-4V Friction Stir Welds Using Numerical-Analytical Basis Functions with Pseudo-Advection

    NASA Astrophysics Data System (ADS)

    Lambrakos, S. G.

    2018-04-01

    Inverse thermal analysis of Ti-6Al-4V friction stir welds is presented that demonstrates application of a methodology using numerical-analytical basis functions and temperature-field constraint conditions. This analysis provides parametric representation of friction-stir-weld temperature histories that can be adopted as input data to computational procedures for prediction of solid-state phase transformations and mechanical response. These parameterized temperature histories can be used for inverse thermal analysis of friction stir welds having process conditions similar those considered here. Case studies are presented for inverse thermal analysis of friction stir welds that use three-dimensional constraint conditions on calculated temperature fields, which are associated with experimentally measured transformation boundaries and weld-stir-zone cross sections.

  2. Determinants of Gastroesophageal Reflux Disease, Including Hookah Smoking and Opium Use– A Cross-Sectional Analysis of 50,000 Individuals

    PubMed Central

    Islami, Farhad; Nasseri-Moghaddam, Siavosh; Pourshams, Akram; Poustchi, Hossein; Semnani, Shahryar; Kamangar, Farin; Etemadi, Arash; Merat, Shahin; Khoshnia, Masoud; Dawsey, Sanford M.; Pharoah, Paul D.; Brennan, Paul; Abnet, Christian C.; Boffetta, Paolo; Malekzadeh, Reza

    2014-01-01

    Background Gastroesophageal reflux disease (GERD) is a common cause of discomfort and morbidity worldwide. However, information on determinants of GERD from large-scale studies in low- to medium-income countries is limited. We investigated the factors associated with different measures of GERD symptoms, including frequency, patient-perceived severity, and onset time. Methods We performed a cross-sectional analysis of the baseline data from a population-based cohort study of ∼50,000 individuals in in Golestan Province, Iran. GERD symptoms in this study included regurgitation and/or heartburn. Results Approximately 20% of participants reported at least weekly symptoms. Daily symptoms were less commonly reported by men, those of Turkmen ethnicity, and nass chewers. On the other hand, age, body mass index, alcohol drinking, cigarette smoking, opium use, lower socioeconomic status, and lower physical activity were associated with daily symptoms. Most of these factors showed similar associations with severe symptoms. Women with higher BMI and waist to hip ratio were more likely to report frequent and severe GERD symptoms. Hookah smoking (OR 1.34, 95% CI 1.02–1.75) and opium use (OR 1.70, 95% CI 1.55–1.87) were associated with severe symptoms, whereas nass chewing had an inverse association (OR 0.87, 95% CI 0.76–0.99). After exclusion of cigarette smokers, hookah smoking was still positively associated and nass chewing was inversely associated with GERD symptoms (all frequencies combined). Conclusion GERD is common in this population. The associations of hookah and opium use and inverse association of nass use with GERD symptoms are reported for the first time. Further studies are required to investigate the nature of these associations. Other determinants of GERD were mostly comparable to those reported elsewhere. PMID:24586635

  3. Clinical knowledge-based inverse treatment planning

    NASA Astrophysics Data System (ADS)

    Yang, Yong; Xing, Lei

    2004-11-01

    Clinical IMRT treatment plans are currently made using dose-based optimization algorithms, which do not consider the nonlinear dose-volume effects for tumours and normal structures. The choice of structure specific importance factors represents an additional degree of freedom of the system and makes rigorous optimization intractable. The purpose of this work is to circumvent the two problems by developing a biologically more sensible yet clinically practical inverse planning framework. To implement this, the dose-volume status of a structure was characterized by using the effective volume in the voxel domain. A new objective function was constructed with the incorporation of the volumetric information of the system so that the figure of merit of a given IMRT plan depends not only on the dose deviation from the desired distribution but also the dose-volume status of the involved organs. The conventional importance factor of an organ was written into a product of two components: (i) a generic importance that parametrizes the relative importance of the organs in the ideal situation when the goals for all the organs are met; (ii) a dose-dependent factor that quantifies our level of clinical/dosimetric satisfaction for a given plan. The generic importance can be determined a priori, and in most circumstances, does not need adjustment, whereas the second one, which is responsible for the intractable behaviour of the trade-off seen in conventional inverse planning, was determined automatically. An inverse planning module based on the proposed formalism was implemented and applied to a prostate case and a head-neck case. A comparison with the conventional inverse planning technique indicated that, for the same target dose coverage, the critical structure sparing was substantially improved for both cases. The incorporation of clinical knowledge allows us to obtain better IMRT plans and makes it possible to auto-select the importance factors, greatly facilitating the inverse planning process. The new formalism proposed also reveals the relationship between different inverse planning schemes and gives important insight into the problem of therapeutic plan optimization. In particular, we show that the EUD-based optimization is a special case of the general inverse planning formalism described in this paper.

  4. Investigation of inversion polymorphisms in the human genome using principal components analysis.

    PubMed

    Ma, Jianzhong; Amos, Christopher I

    2012-01-01

    Despite the significant advances made over the last few years in mapping inversions with the advent of paired-end sequencing approaches, our understanding of the prevalence and spectrum of inversions in the human genome has lagged behind other types of structural variants, mainly due to the lack of a cost-efficient method applicable to large-scale samples. We propose a novel method based on principal components analysis (PCA) to characterize inversion polymorphisms using high-density SNP genotype data. Our method applies to non-recurrent inversions for which recombination between the inverted and non-inverted segments in inversion heterozygotes is suppressed due to the loss of unbalanced gametes. Inside such an inversion region, an effect similar to population substructure is thus created: two distinct "populations" of inversion homozygotes of different orientations and their 1:1 admixture, namely the inversion heterozygotes. This kind of substructure can be readily detected by performing PCA locally in the inversion regions. Using simulations, we demonstrated that the proposed method can be used to detect and genotype inversion polymorphisms using unphased genotype data. We applied our method to the phase III HapMap data and inferred the inversion genotypes of known inversion polymorphisms at 8p23.1 and 17q21.31. These inversion genotypes were validated by comparing with literature results and by checking Mendelian consistency using the family data whenever available. Based on the PCA-approach, we also performed a preliminary genome-wide scan for inversions using the HapMap data, which resulted in 2040 candidate inversions, 169 of which overlapped with previously reported inversions. Our method can be readily applied to the abundant SNP data, and is expected to play an important role in developing human genome maps of inversions and exploring associations between inversions and susceptibility of diseases.

  5. An empirical approach to inversion of an unconventional helicopter electromagnetic dataset

    USGS Publications Warehouse

    Pellerin, L.; Labson, V.F.

    2003-01-01

    A helicopter electromagnetic (HEM) survey acquired at the U.S. Idaho National Engineering and Environmental Laboratory (INEEL) used a modification of a traditional mining airborne method flown at low levels for detailed characterization of shallow waste sites. The low sensor height, used to increase resolution, invalidates standard assumptions used in processing HEM data. Although the survey design strategy was sound, traditional interpretation techniques, routinely used in industry, proved ineffective. Processed data and apparent resistivity maps were severely distorted, and hence unusable, due to low flight height effects, high magnetic permeability of the basalt host, and the conductive, three-dimensional nature of the waste site targets.To accommodate these interpretation challenges, we modified a one-dimensional inversion routine to include a linear term in the objective function that allows for the magnetic and three-dimensional electromagnetic responses in the in-phase data. Although somewhat ad hoc, the use of this term in the inverse routine, referred to as the shift factor, was successful in defining the waste sites and reducing noise due to the low flight height and magnetic characteristics of the host rock. Many inversion scenarios were applied to the data and careful analysis was necessary to determine the parameters appropriate for interpretation, hence the approach was empirical. Data from three areas were processed with this scheme to highlight different interpretational aspects of the method. Wastes sites were delineated with the shift terms in two of the areas, allowing for separation of the anthropomorphic targets from the natural one-dimensional host. In the third area, the estimated resistivity and the shift factor were used for geological mapping. The high magnetic content of the native soil enabled the mapping of disturbed soil with the shift term. Published by Elsevier Science B.V.

  6. Parallel solution of the symmetric tridiagonal eigenproblem. Research report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jessup, E.R.

    1989-10-01

    This thesis discusses methods for computing all eigenvalues and eigenvectors of a symmetric tridiagonal matrix on a distributed-memory Multiple Instruction, Multiple Data multiprocessor. Only those techniques having the potential for both high numerical accuracy and significant large-grained parallelism are investigated. These include the QL method or Cuppen's divide and conquer method based on rank-one updating to compute both eigenvalues and eigenvectors, bisection to determine eigenvalues and inverse iteration to compute eigenvectors. To begin, the methods are compared with respect to computation time, communication time, parallel speed up, and accuracy. Experiments on an IPSC hypercube multiprocessor reveal that Cuppen's method ismore » the most accurate approach, but bisection with inverse iteration is the fastest and most parallel. Because the accuracy of the latter combination is determined by the quality of the computed eigenvectors, the factors influencing the accuracy of inverse iteration are examined. This includes, in part, statistical analysis of the effect of a starting vector with random components. These results are used to develop an implementation of inverse iteration producing eigenvectors with lower residual error and better orthogonality than those generated by the EISPACK routine TINVIT. This thesis concludes with adaptions of methods for the symmetric tridiagonal eigenproblem to the related problem of computing the singular value decomposition (SVD) of a bidiagonal matrix.« less

  7. Parallel solution of the symmetric tridiagonal eigenproblem

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jessup, E.R.

    1989-01-01

    This thesis discusses methods for computing all eigenvalues and eigenvectors of a symmetric tridiagonal matrix on a distributed memory MIMD multiprocessor. Only those techniques having the potential for both high numerical accuracy and significant large-grained parallelism are investigated. These include the QL method or Cuppen's divide and conquer method based on rank-one updating to compute both eigenvalues and eigenvectors, bisection to determine eigenvalues, and inverse iteration to compute eigenvectors. To begin, the methods are compared with respect to computation time, communication time, parallel speedup, and accuracy. Experiments on an iPSC hyper-cube multiprocessor reveal that Cuppen's method is the most accuratemore » approach, but bisection with inverse iteration is the fastest and most parallel. Because the accuracy of the latter combination is determined by the quality of the computed eigenvectors, the factors influencing the accuracy of inverse iteration are examined. This includes, in part, statistical analysis of the effects of a starting vector with random components. These results are used to develop an implementation of inverse iteration producing eigenvectors with lower residual error and better orthogonality than those generated by the EISPACK routine TINVIT. This thesis concludes with adaptations of methods for the symmetric tridiagonal eigenproblem to the related problem of computing the singular value decomposition (SVD) of a bidiagonal matrix.« less

  8. Estimation of near-surface shear-wave velocity by inversion of Rayleigh waves

    USGS Publications Warehouse

    Xia, J.; Miller, R.D.; Park, C.B.

    1999-01-01

    The shear-wave (S-wave) velocity of near-surface materials (soil, rocks, pavement) and its effect on seismic-wave propagation are of fundamental interest in many groundwater, engineering, and environmental studies. Rayleigh-wave phase velocity of a layered-earth model is a function of frequency and four groups of earth properties: P-wave velocity, S-wave velocity, density, and thickness of layers. Analysis of the Jacobian matrix provides a measure of dispersion-curve sensitivity to earth properties. S-wave velocities are the dominant influence on a dispersion curve in a high-frequency range (>5 Hz) followed by layer thickness. An iterative solution technique to the weighted equation proved very effective in the high-frequency range when using the Levenberg-Marquardt and singular-value decomposition techniques. Convergence of the weighted solution is guaranteed through selection of the damping factor using the Levenberg-Marquardt method. Synthetic examples demonstrated calculation efficiency and stability of inverse procedures. We verify our method using borehole S-wave velocity measurements.Iterative solutions to the weighted equation by the Levenberg-Marquardt and singular-value decomposition techniques are derived to estimate near-surface shear-wave velocity. Synthetic and real examples demonstrate the calculation efficiency and stability of the inverse procedure. The inverse results of the real example are verified by borehole S-wave velocity measurements.

  9. Hadronic Form Factors in Asymptotically Free Field Theories

    DOE R&D Accomplishments Database

    Gross, D. J.; Treiman, S. B.

    1974-01-01

    The breakdown of Bjorken scaling in asymptotically free gauge theories of the strong interactions is explored for its implications on the large q{sup 2} behavior of nucleon form factors. Duality arguments of Bloom and Gilman suggest a connection between the form factors and the threshold properties of the deep inelastic structure functions. The latter are addressed directly in an analysis of asymptotically free theories; and through the duality connection we are then led to statements about the form factors. For very large q{sup 2} the form factors are predicted to fall faster than any inverse power of q{sup 2}. For the more modest range of q{sup 2} reached in existing experiments the agreement with data is fairly good, though this may well be fortuitous. Extrapolations beyond this range are presented.

  10. Molecular analysis of recombination in a family with Duchenne muscular dystrophy and a large pericentric X chromosome inversion.

    PubMed Central

    Shashi, V.; Golden, W. L.; Allinson, P. S.; Blanton, S. H.; von Kap-Herr, C.; Kelly, T. E.

    1996-01-01

    It has been demonstrated in animal studies that, in animals heterozygous for pericentric chromosomal inversions, loop formation is greatly reduced during meiosis. This results in absence of recombination within the inverted segment, with recombination seen only outside the inversion. A recent study in yeast has shown that telomeres, rather than centromeres, lead in chromosome movement just prior to meiosis and may be involved in promoting recombination. We studied by cytogenetic analysis and DNA polymorphisms the nature of meiotic recombination in a three-generation family with a large pericentric X chromosome inversion, inv(X)(p21.1q26), in which Duchenne muscular dystrophy (DMD) was cosegregating with the inversion. On DNA analysis there was no evidence of meiotic recombination between the inverted and normal X chromosomes in the inverted segment. Recombination was seen at the telomeric regions, Xp22 and Xq27-28. No deletion or point mutation was found on analysis of the DMD gene. On the basis of the FISH results, we believe that the X inversion is the mutation responsible for DMD in this family. Our results indicate that (1) pericentric X chromosome inversions result in reduction of recombination between the normal and inverted X chromosomes; (2) meiotic X chromosome pairing in these individuals is likely initiated at the telomeres; and (3) in this family DMD is caused by the pericentric inversion. Images Figure 2 Figure 5 Figure 6 Figure 7 PMID:8651300

  11. Genotyping the factor VIII intron 22 inversion locus using fluorescent in situ hybridization.

    PubMed

    Sheen, Campbell R; McDonald, Margaret A; George, Peter M; Smith, Mark P; Morris, Christine M

    2011-02-15

    The factor VIII intron 22 inversion is the most common cause of hemophilia A, accounting for approximately 40% of all severe cases of the disease. Southern hybridization and multiplex long distance PCR are the most commonly used techniques to detect the inversion in a diagnostic setting, although both have significant limitations. Here we describe our experience establishing a multicolor fluorescent in situ hybridization (FISH) based assay as an alternative to existing methods for genetic diagnosis of the inversion. Our assay was designed to apply three differentially labelled BAC DNA probes that when hybridized to interphase nuclei would exhibit signal patterns that are consistent with the normal or the inversion locus. When the FISH assay was applied to five normal and five inversion male samples, the correct genotype was assignable with p<0.001 for all samples. When applied to carrier female samples the assay could not assign a genotype to all female samples, probably due to a lower proportion of informative nuclei in female samples caused by the added complexity of a second X chromosome. Despite this complication, these pilot findings show that the assay performs favourably compared to the commonly used methods. Copyright © 2010 Elsevier Inc. All rights reserved.

  12. Evidence for large inversion polymorphisms in the human genome from HapMap data

    PubMed Central

    Bansal, Vikas; Bashir, Ali; Bafna, Vineet

    2007-01-01

    Knowledge about structural variation in the human genome has grown tremendously in the past few years. However, inversions represent a class of structural variation that remains difficult to detect. We present a statistical method to identify large inversion polymorphisms using unusual Linkage Disequilibrium (LD) patterns from high-density SNP data. The method is designed to detect chromosomal segments that are inverted (in a majority of the chromosomes) in a population with respect to the reference human genome sequence. We demonstrate the power of this method to detect such inversion polymorphisms through simulations done using the HapMap data. Application of this method to the data from the first phase of the International HapMap project resulted in 176 candidate inversions ranging from 200 kb to several megabases in length. Our predicted inversions include an 800-kb polymorphic inversion at 7p22, a 1.1-Mb inversion at 16p12, and a novel 1.2-Mb inversion on chromosome 10 that is supported by the presence of two discordant fosmids. Analysis of the genomic sequence around inversion breakpoints showed that 11 predicted inversions are flanked by pairs of highly homologous repeats in the inverted orientation. In addition, for three candidate inversions, the inverted orientation is represented in the Celera genome assembly. Although the power of our method to detect inversions is restricted because of inherently noisy LD patterns in population data, inversions predicted by our method represent strong candidates for experimental validation and analysis. PMID:17185644

  13. A parallel algorithm for 2D visco-acoustic frequency-domain full-waveform inversion: application to a dense OBS data set

    NASA Astrophysics Data System (ADS)

    Sourbier, F.; Operto, S.; Virieux, J.

    2006-12-01

    We present a distributed-memory parallel algorithm for 2D visco-acoustic full-waveform inversion of wide-angle seismic data. Our code is written in fortran90 and use MPI for parallelism. The algorithm was applied to real wide-angle data set recorded by 100 OBSs with a 1-km spacing in the eastern-Nankai trough (Japan) to image the deep structure of the subduction zone. Full-waveform inversion is applied sequentially to discrete frequencies by proceeding from the low to the high frequencies. The inverse problem is solved with a classic gradient method. Full-waveform modeling is performed with a frequency-domain finite-difference method. In the frequency-domain, solving the wave equation requires resolution of a large unsymmetric system of linear equations. We use the massively parallel direct solver MUMPS (http://www.enseeiht.fr/irit/apo/MUMPS) for distributed-memory computer to solve this system. The MUMPS solver is based on a multifrontal method for the parallel factorization. The MUMPS algorithm is subdivided in 3 main steps: a symbolic analysis step that performs re-ordering of the matrix coefficients to minimize the fill-in of the matrix during the subsequent factorization and an estimation of the assembly tree of the matrix. Second, the factorization is performed with dynamic scheduling to accomodate numerical pivoting and provides the LU factors distributed over all the processors. Third, the resolution is performed for multiple sources. To compute the gradient of the cost function, 2 simulations per shot are required (one to compute the forward wavefield and one to back-propagate residuals). The multi-source resolutions can be performed in parallel with MUMPS. In the end, each processor stores in core a sub-domain of all the solutions. These distributed solutions can be exploited to compute in parallel the gradient of the cost function. Since the gradient of the cost function is a weighted stack of the shot and residual solutions of MUMPS, each processor computes the corresponding sub-domain of the gradient. In the end, the gradient is centralized on the master processor using a collective communation. The gradient is scaled by the diagonal elements of the Hessian matrix. This scaling is computed only once per frequency before the first iteration of the inversion. Estimation of the diagonal terms of the Hessian requires performing one simulation per non redondant shot and receiver position. The same strategy that the one used for the gradient is used to compute the diagonal Hessian in parallel. This algorithm was applied to a dense wide-angle data set recorded by 100 OBSs in the eastern Nankai trough, offshore Japan. Thirteen frequencies ranging from 3 and 15 Hz were inverted. Tweny iterations per frequency were computed leading to 260 tomographic velocity models of increasing resolution. The velocity model dimensions are 105 km x 25 km corresponding to a finite-difference grid of 4201 x 1001 grid with a 25-m grid interval. The number of shot was 1005 and the number of inverted OBS gathers was 93. The inversion requires 20 days on 6 32-bits bi-processor nodes with 4 Gbytes of RAM memory per node when only the LU factorization is performed in parallel. Preliminary estimations of the time required to perform the inversion with the fully-parallelized code is 6 and 4 days using 20 and 50 processors respectively.

  14. Analysis Code - Data Analysis in 'Leveraging Multiple Statistical Methods for Inverse Prediction in Nuclear Forensics Applications' (LMSMIPNFA) v. 1.0

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lewis, John R

    R code that performs the analysis of a data set presented in the paper ‘Leveraging Multiple Statistical Methods for Inverse Prediction in Nuclear Forensics Applications’ by Lewis, J., Zhang, A., Anderson-Cook, C. It provides functions for doing inverse predictions in this setting using several different statistical methods. The data set is a publicly available data set from a historical Plutonium production experiment.

  15. Spatial delineation, fluid-lithology characterization, and petrophysical modeling of deepwater Gulf of Mexico reservoirs though joint AVA deterministic and stochastic inversion of three-dimensional partially-stacked seismic amplitude data and well logs

    NASA Astrophysics Data System (ADS)

    Contreras, Arturo Javier

    This dissertation describes a novel Amplitude-versus-Angle (AVA) inversion methodology to quantitatively integrate pre-stack seismic data, well logs, geologic data, and geostatistical information. Deterministic and stochastic inversion algorithms are used to characterize flow units of deepwater reservoirs located in the central Gulf of Mexico. A detailed fluid/lithology sensitivity analysis was conducted to assess the nature of AVA effects in the study area. Standard AVA analysis indicates that the shale/sand interface represented by the top of the hydrocarbon-bearing turbidite deposits generate typical Class III AVA responses. Layer-dependent Biot-Gassmann analysis shows significant sensitivity of the P-wave velocity and density to fluid substitution, indicating that presence of light saturating fluids clearly affects the elastic response of sands. Accordingly, AVA deterministic and stochastic inversions, which combine the advantages of AVA analysis with those of inversion, have provided quantitative information about the lateral continuity of the turbidite reservoirs based on the interpretation of inverted acoustic properties and fluid-sensitive modulus attributes (P-Impedance, S-Impedance, density, and LambdaRho, in the case of deterministic inversion; and P-velocity, S-velocity, density, and lithotype (sand-shale) distributions, in the case of stochastic inversion). The quantitative use of rock/fluid information through AVA seismic data, coupled with the implementation of co-simulation via lithotype-dependent multidimensional joint probability distributions of acoustic/petrophysical properties, provides accurate 3D models of petrophysical properties such as porosity, permeability, and water saturation. Pre-stack stochastic inversion provides more realistic and higher-resolution results than those obtained from analogous deterministic techniques. Furthermore, 3D petrophysical models can be more accurately co-simulated from AVA stochastic inversion results. By combining AVA sensitivity analysis techniques with pre-stack stochastic inversion, geologic data, and awareness of inversion pitfalls, it is possible to substantially reduce the risk in exploration and development of conventional and non-conventional reservoirs. From the final integration of deterministic and stochastic inversion results with depositional models and analogous examples, the M-series reservoirs have been interpreted as stacked terminal turbidite lobes within an overall fan complex (the Miocene MCAVLU Submarine Fan System); this interpretation is consistent with previous core data interpretations and regional stratigraphic/depositional studies.

  16. Association of educational status with cardiovascular disease: Teheran Lipid and Glucose Study.

    PubMed

    Hajsheikholeslami, Farhad; Hatami, Masumeh; Hadaegh, Farzad; Ghanbarian, Arash; Azizi, Fereidoun

    2011-06-01

    The aim of this study was to evaluate the associations between educational level and cardiovascular disease (CVD) in an older Iranian population. To estimate the odds ratio (OR) of educational level in a cross-sectional study, logistic regression analysis was used on 1,788 men and 2,204 women (222 men and 204 women positive based on their CVD status) aged ≥ 45 years. In men, educational levels of college degree and literacy level below diploma were inversely associated with CVD in the multivariate model [0.52 (0.28-0.94), 0.61 (0.40-0.92), respectively], but diploma level did not show any significant association with CVD, neither in the crude model nor in the multivariate model. In women, increase in educational level was inversely associated with risk of CVD in the crude model, but in the multivariate adjusted model, literacy level below diploma decreased risk of CVD by 39%, compared with illiteracy. Our findings support those of developed countries that, along with other CVD risk factors, educational status has an inverse association with CVD among a representative Iranian population of older men and women.

  17. [Comparisons and analysis of the spectral response functions' difference between FY-2E's and FY2C's split window channels].

    PubMed

    Zhang, Yong; Li, Yuan; Rong, Zhi-Guo

    2010-06-01

    Remote sensors' channel spectral response function (SRF) was one of the key factors to influence the quantitative products' inversion algorithm, accuracy and the geophysical characteristics. Aiming at the adjustments of FY-2E's split window channels' SRF, detailed comparisons between the FY-2E and FY-2C corresponding channels' SRF differences were carried out based on three data collections: the NOAA AVHRR corresponding channels' calibration look up tables, field measured water surface radiance and atmospheric profiles at Lake Qinghai and radiance calculated from the PLANK function within all dynamic range of FY-2E/C. The results showed that the adjustments of FY-2E's split window channels' SRF would result in the spectral range's movements and influence the inversion algorithms of some ground quantitative products. On the other hand, these adjustments of FY-2E SRFs would increase the brightness temperature differences between FY-2E's two split window channels within all dynamic range relative to FY-2C's. This would improve the inversion ability of FY-2E's split window channels.

  18. Genetics Home Reference: core binding factor acute myeloid leukemia

    MedlinePlus

    ... the CBFB gene. One such rearrangement, called an inversion , involves breakage of a chromosome in two places; ... is reversed and reinserted into the chromosome. The inversion involved in CBF-AML (written as inv(16)) ...

  19. Inversed estimation of critical factors for controlling over-prediction of summertime tropospheric O3 over East Asia based of the combination of DDM sensitivity analysis and modeled Green's function method

    NASA Astrophysics Data System (ADS)

    Itahashi, S.; Yumimoto, K.; Uno, I.; Kim, S.

    2012-12-01

    Air quality studies based on the chemical transport model have been provided many important results for promoting our knowledge of air pollution phenomena, however, discrepancies between modeling results and observation data are still important issue to overcome. One of the concerning issue would be an over-prediction of summertime tropospheric ozone in remote area of Japan. This problem has been pointed out in the model comparison study of both regional scale (e.g., MICS-Asia) and global scale model (e.g., TH-FTAP). Several reasons for this issue can be listed as, (i) the modeled reproducibility on the penetration of clean oceanic air mass, (ii) correct estimation of the anthropogenic NOx / VOC emissions over East Asia, (iii) the chemical reaction scheme used in model simulation. In this study, we attempt to inverse estimation of some important chemical reactions based on the combining system of DDM (decoupled direct method) sensitivity analysis and modeled Green's function approach. The decoupled direct method (DDM) is an efficient and accurate way of performing sensitivity analysis to model inputs, calculates sensitivity coefficients representing the responsiveness of atmospheric chemical concentrations to perturbations in a model input or parameter. The inverse solutions with the Green's functions are given by a linear, least-squares method but are still robust against nonlinearities, To construct the response matrix (i.e., Green's functions), we can directly use the results of DDM sensitivity analysis. The solution of chemical reaction constants which have relatively large uncertainties are determined with constraints of observed ozone concentration data over the remote area in Japan. Our inversed estimation demonstrated that the underestimation of reaction constant to produce HNO3 (NO2 + OH + M → HNO3 + M) in SAPRC99 chemical scheme, and the inversed results indicated the +29.0 % increment to this reaction. This estimation has good agreement when compared with the CB4 and CB5, and also to the SAPRC07 estimation. For the NO2 photolysis rates, 49.4 % reduction was pronounced. This result indicates the importance of heavy aerosol effect for the change of photolysis rate must be incorporated in the numerical study.

  20. Spring photosynthetic onset and net CO2 uptake in Alaska triggered by landscape thawing.

    PubMed

    Parazoo, Nicholas C; Arneth, Almut; Pugh, Thomas A M; Smith, Ben; Steiner, Nicholas; Luus, Kristina; Commane, Roisin; Benmergui, Josh; Stofferahn, Eric; Liu, Junjie; Rödenbeck, Christian; Kawa, Randy; Euskirchen, Eugenie; Zona, Donatella; Arndt, Kyle; Oechel, Walt; Miller, Charles

    2018-04-24

    The springtime transition to regional-scale onset of photosynthesis and net ecosystem carbon uptake in boreal and tundra ecosystems are linked to the soil freeze-thaw state. We present evidence from diagnostic and inversion models constrained by satellite fluorescence and airborne CO 2 from 2012 to 2014 indicating the timing and magnitude of spring carbon uptake in Alaska correlates with landscape thaw and ecoregion. Landscape thaw in boreal forests typically occurs in late April (DOY 111 ± 7) with a 29 ± 6 day lag until photosynthetic onset. North Slope tundra thaws 3 weeks later (DOY 133 ± 5) but experiences only a 20 ± 5 day lag until photosynthetic onset. These time lag differences reflect efficient cold season adaptation in tundra shrub and the longer dehardening period for boreal evergreens. Despite the short transition from thaw to photosynthetic onset in tundra, synchrony of tundra respiration with snow melt and landscape thaw delays the transition from net carbon loss (at photosynthetic onset) to net uptake by 13 ± 7 days, thus reducing the tundra net carbon uptake period. Two global CO 2 inversions using a CASA-GFED model prior estimate earlier northern high latitude net carbon uptake compared to our regional inversion, which we attribute to (i) early photosynthetic-onset model prior bias, (ii) inverse method (scaling factor + optimization window), and (iii) sparsity of available Alaskan CO 2 observations. Another global inversion with zero prior estimates the same timing for net carbon uptake as the regional model but smaller seasonal amplitude. The analysis of Alaskan eddy covariance observations confirms regional scale findings for tundra, but indicates that photosynthesis and net carbon uptake occur up to 1 month earlier in evergreens than captured by models or CO 2 inversions, with better correlation to above-freezing air temperature than date of primary thaw. Further collection and analysis of boreal evergreen species over multiple years and at additional subarctic flux towers are critically needed. © 2018 John Wiley & Sons Ltd.

  1. Inverse Function: Pre-Service Teachers' Techniques and Meanings

    ERIC Educational Resources Information Center

    Paoletti, Teo; Stevens, Irma E.; Hobson, Natalie L. F.; Moore, Kevin C.; LaForest, Kevin R.

    2018-01-01

    Researchers have argued teachers and students are not developing connected meanings for function inverse, thus calling for a closer examination of teachers' and students' inverse function meanings. Responding to this call, we characterize 25 pre-service teachers' inverse function meanings as inferred from our analysis of clinical interviews. After…

  2. IGFBP6 Regulates Cell Apoptosis and Migration in Glioma.

    PubMed

    Bei, Yuanqi; Huang, Qingfeng; Shen, Jianhong; Shi, Jinlong; Shen, Chaoyan; Xu, Peng; Chang, Hao; Xia, Xiaojie; Xu, Li; Ji, Bin; Chen, JianGuo

    2017-07-01

    The insulin-like growth factor binding protein 6 (IGFBP6), as an inhibitor of IGF-II actions, plays an important role in inhibiting survival and migration of tumor cells. In our study, we intended to demonstrate the biological function of IGFBP6 in the development of glioma and its clinical significance. Firstly, Western blot and immunohistochemistry revealed that the expression of IGFBP6 inversely correlated with glioma grade. Secondly, multivariate analysis with the Cox proportional hazards model and Kaplan-Meier analysis indicated that IGFBP6 could be an independent prognostic factor for the survival of glioma patients. In addition, overexpression of IGFBP6 induced glioma cell apoptosis, and depletion of IGFBP6 had the opposite action. Finally, overexpression of IGFBP6 inhibited migration of glioma cells, and depletion of IGFBP6 had the opposite action. Together our findings suggest that IGFBP6 might be an important regulator and prognostic factor for glioma.

  3. Prevalence, pattern, and determinants of placental malaria in a population of southeastern Nigerian parturients.

    PubMed

    Ezebialu, Ifeanyichukwu U; Eke, Ahizechukwu C; Ezeagwuna, Dorothy A; Nwachukwu, Chukwuemeka E; Ifediata, Francis; Ezebialu, Chinenye U

    2012-12-01

    Placental malaria is a complication of malaria in pregnancy and is associated with adverse outcomes. Its burden is highest in Sub-Saharan Africa, but despite this, data based on histological analysis are scarce from this region. Questionnaires administered by the researchers were used to obtain information from parturients at a university teaching hospital in southeastern Nigeria between April and November 2010. Maternal blood and placental blood were collected for analysis. Placental blocks were taken for histological analysis. Statistical analyses were done using SPSS v. 17. Three hundred and sixty-five placentas were analyzed, out of which 254 showed histological evidence of malaria parasitization, giving a prevalence of 69.6%. Of the 254 placentas, 23 (9.0%) showed active infection and 196 (77.2%) showed active-on-past infection, while 35 (13.8%) showed past infection. Rural residence, hemoglobin genotype AA, not receiving intermittent preventive treatment in pregnancy (IPTp), and not sleeping under insecticide-treated bed nets (ITN) were significantly associated with placental malaria. Placental parasite density was inversely related to parity. This study showed that the prevalence of placental malaria in southeastern Nigeria is high, and demonstrated that the mean parasite density was inversely related to parity. Significant factors associated with placental malaria were also identified. Appreciation of these significant factors will assist program managers in implementing the strategies for the prevention of malaria in pregnancy. Copyright © 2012 International Society for Infectious Diseases. All rights reserved.

  4. Tomographic inversion of time-domain resistivity and chargeability data for the investigation of landfills using a priori information.

    PubMed

    De Donno, Giorgio; Cardarelli, Ettore

    2017-01-01

    In this paper, we present a new code for the modelling and inversion of resistivity and chargeability data using a priori information to improve the accuracy of the reconstructed model for landfill. When a priori information is available in the study area, we can insert them by means of inequality constraints on the whole model or on a single layer or assigning weighting factors for enhancing anomalies elongated in the horizontal or vertical directions. However, when we have to face a multilayered scenario with numerous resistive to conductive transitions (the case of controlled landfills), the effective thickness of the layers can be biased. The presented code includes a model-tuning scheme, which is applied after the inversion of field data, where the inversion of the synthetic data is performed based on an initial guess, and the absolute difference between the field and synthetic inverted models is minimized. The reliability of the proposed approach has been supported in two real-world examples; we were able to identify an unauthorized landfill and to reconstruct the geometrical and physical layout of an old waste dump. The combined analysis of the resistivity and chargeability (normalised) models help us to remove ambiguity due to the presence of the waste mass. Nevertheless, the presence of certain layers can remain hidden without using a priori information, as demonstrated by a comparison of the constrained inversion with a standard inversion. The robustness of the above-cited method (using a priori information in combination with model tuning) has been validated with the cross-section from the construction plans, where the reconstructed model is in agreement with the original design. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Navier-Stokes simulation of plume/Vertical Launching System interaction flowfields

    NASA Astrophysics Data System (ADS)

    York, B. J.; Sinha, N.; Dash, S. M.; Anderson, L.; Gominho, L.

    1992-01-01

    The application of Navier-Stokes methodology to the analysis of Vertical Launching System/missile exhaust plume interactions is discussed. The complex 3D flowfields related to the Vertical Launching System are computed utilizing the PARCH/RNP Navier-Stokes code. PARCH/RNP solves the fully-coupled system of fluid, two-equation turbulence (k-epsilon) and chemical species equations via the implicit, approximately factored, Beam-Warming algorithm utilizing a block-tridiagonal inversion procedure.

  6. New Inversion and Interpretation of Public-Domain Electromagnetic Survey Data from Selected Areas in Alaska

    NASA Astrophysics Data System (ADS)

    Smith, B. D.; Kass, A.; Saltus, R. W.; Minsley, B. J.; Deszcz-Pan, M.; Bloss, B. R.; Burns, L. E.

    2013-12-01

    Public-domain airborne geophysical surveys (combined electromagnetics and magnetics), mostly collected for and released by the State of Alaska, Division of Geological and Geophysical Surveys (DGGS), are a unique and valuable resource for both geologic interpretation and geophysical methods development. A new joint effort by the US Geological Survey (USGS) and the DGGS aims to add value to these data through the application of novel advanced inversion methods and through innovative and intuitive display of data: maps, profiles, voxel-based models, and displays of estimated inversion quality and confidence. Our goal is to make these data even more valuable for interpretation of geologic frameworks, geotechnical studies, and cryosphere studies, by producing robust estimates of subsurface resistivity that can be used by non-geophysicists. The available datasets, which are available in the public domain, include 39 frequency-domain electromagnetic datasets collected since 1993, and continue to grow with 5 more data releases pending in 2013. The majority of these datasets were flown for mineral resource purposes, with one survey designed for infrastructure analysis. In addition, several USGS datasets are included in this study. The USGS has recently developed new inversion methodologies for airborne EM data and have begun to apply these and other new techniques to the available datasets. These include a trans-dimensional Markov Chain Monte Carlo technique, laterally-constrained regularized inversions, and deterministic inversions which include calibration factors as a free parameter. Incorporation of the magnetic data as an additional constraining dataset has also improved the inversion results. Processing has been completed in several areas, including Fortymile and the Alaska Highway surveys, and continues in others such as the Styx River and Nome surveys. Utilizing these new techniques, we provide models beyond the apparent resistivity maps supplied by the original contractors, allowing us to produce a variety of products, such as maps of resistivity as a function of depth or elevation, cross section maps, and 3D voxel models, which have been treated consistently both in terms of processing and error analysis throughout the state. These products facilitate a more fruitful exchange between geologists and geophysicists and a better understanding of uncertainty, and the process results in iterative development and improvement of geologic models, both on small and large scales.

  7. Analysis of phases in the structure determination of an icosahedral virus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Plevka, Pavel; Kaufmann, Bärbel; Rossmann, Michael G.

    2012-03-15

    The constraints imposed on structure-factor phases by noncrystallographic symmetry (NCS) allow phase improvement, phase extension to higher resolution and hence ab initio phase determination. The more numerous the NCS redundancy and the greater the volume used for solvent flattening, the greater the power for phase determination. In a case analyzed here the icosahedral NCS phasing appeared to have broken down, although later successful phase extension was possible when the envelope around the NCS region was tightened. The phases from the failed phase-determination attempt fell into four classes, all of which satisfied the NCS constraints. These four classes corresponded to themore » correct solution, opposite enantiomorph, Babinet inversion and opposite enantiomorph with Babinet inversion. These incorrect solutions can be seeded from structure factors belonging to reciprocal-space volumes that lie close to icosahedral NCS axes where the structure amplitudes tend to be large and the phases tend to be 0 or {pi}. Furthermore, the false solutions can spread more easily if there are large errors in defining the envelope designating the region in which NCS averaging is performed.« less

  8. Analysis of phases in the structure determination of an icosahedral virus.

    PubMed

    Plevka, Pavel; Kaufmann, Bärbel; Rossmann, Michael G

    2011-06-01

    The constraints imposed on structure-factor phases by noncrystallographic symmetry (NCS) allow phase improvement, phase extension to higher resolution and hence ab initio phase determination. The more numerous the NCS redundancy and the greater the volume used for solvent flattening, the greater the power for phase determination. In a case analyzed here the icosahedral NCS phasing appeared to have broken down, although later successful phase extension was possible when the envelope around the NCS region was tightened. The phases from the failed phase-determination attempt fell into four classes, all of which satisfied the NCS constraints. These four classes corresponded to the correct solution, opposite enantiomorph, Babinet inversion and opposite enantiomorph with Babinet inversion. These incorrect solutions can be seeded from structure factors belonging to reciprocal-space volumes that lie close to icosahedral NCS axes where the structure amplitudes tend to be large and the phases tend to be 0 or π. Furthermore, the false solutions can spread more easily if there are large errors in defining the envelope designating the region in which NCS averaging is performed. © 2011 International Union of Crystallography

  9. Analysis of phases in the structure determination of an icosahedral virus

    PubMed Central

    Plevka, Pavel; Kaufmann, Bärbel; Rossmann, Michael G.

    2011-01-01

    The constraints imposed on structure-factor phases by non­crystallographic symmetry (NCS) allow phase improvement, phase extension to higher resolution and hence ab initio phase determination. The more numerous the NCS redundancy and the greater the volume used for solvent flattening, the greater the power for phase determination. In a case analyzed here the icosahedral NCS phasing appeared to have broken down, although later successful phase extension was possible when the envelope around the NCS region was tightened. The phases from the failed phase-determination attempt fell into four classes, all of which satisfied the NCS constraints. These four classes corresponded to the correct solution, opposite enantiomorph, Babinet inversion and opposite enantiomorph with Babinet inversion. These incorrect solutions can be seeded from structure factors belonging to reciprocal-space volumes that lie close to icosahedral NCS axes where the structure amplitudes tend to be large and the phases tend to be 0 or π. Furthermore, the false solutions can spread more easily if there are large errors in defining the envelope designating the region in which NCS averaging is performed. PMID:21636897

  10. Using CO2:CO Correlations to Improve Inverse Analyses of Carbon Fluxes

    NASA Technical Reports Server (NTRS)

    Palmer, Paul I.; Suntharalingam, Parvadha; Jones, Dylan B. A.; Jacob, Daniel J.; Streets, David G.; Fu, Qingyan; Vay, Stephanie A.; Sachse, Glen W.

    2006-01-01

    Observed correlations between atmospheric concentrations of CO2 and CO represent potentially powerful information for improving CO2 surface flux estimates through coupled CO2-CO inverse analyses. We explore the value of these correlations in improving estimates of regional CO2 fluxes in east Asia by using aircraft observations of CO2 and CO from the TRACE-P campaign over the NW Pacific in March 2001. Our inverse model uses regional CO2 and CO surface fluxes as the state vector, separating biospheric and combustion contributions to CO2. CO2-CO error correlation coefficients are included in the inversion as off-diagonal entries in the a priori and observation error covariance matrices. We derive error correlations in a priori combustion source estimates of CO2 and CO by propagating error estimates of fuel consumption rates and emission factors. However, we find that these correlations are weak because CO source uncertainties are mostly determined by emission factors. Observed correlations between atmospheric CO2 and CO concentrations imply corresponding error correlations in the chemical transport model used as the forward model for the inversion. These error correlations in excess of 0.7, as derived from the TRACE-P data, enable a coupled CO2-CO inversion to achieve significant improvement over a CO2-only inversion for quantifying regional fluxes of CO2.

  11. Inversion for the driving forces of plate tectonics

    NASA Technical Reports Server (NTRS)

    Richardson, R. M.

    1983-01-01

    Inverse modeling techniques have been applied to the problem of determining the roles of various forces that may drive and resist plate tectonic motions. Separate linear inverse problems have been solved to find the best fitting pole of rotation for finite element grid point velocities and to find the best combination of force models to fit the observed relative plate velocities for the earth's twelve major plates using the generalized inverse operator. Variance-covariance data on plate motion have also been included. Results emphasize the relative importance of ridge push forces in the driving mechanism. Convergent margin forces are smaller by at least a factor of two, and perhaps by as much as a factor of twenty. Slab pull, apparently, is poorly transmitted to the surface plate as a driving force. Drag forces at the base of the plate are smaller than ridge push forces, although the sign of the force remains in question.

  12. Investigation of Inversion Polymorphisms in the Human Genome Using Principal Components Analysis

    PubMed Central

    Ma, Jianzhong; Amos, Christopher I.

    2012-01-01

    Despite the significant advances made over the last few years in mapping inversions with the advent of paired-end sequencing approaches, our understanding of the prevalence and spectrum of inversions in the human genome has lagged behind other types of structural variants, mainly due to the lack of a cost-efficient method applicable to large-scale samples. We propose a novel method based on principal components analysis (PCA) to characterize inversion polymorphisms using high-density SNP genotype data. Our method applies to non-recurrent inversions for which recombination between the inverted and non-inverted segments in inversion heterozygotes is suppressed due to the loss of unbalanced gametes. Inside such an inversion region, an effect similar to population substructure is thus created: two distinct “populations” of inversion homozygotes of different orientations and their 1∶1 admixture, namely the inversion heterozygotes. This kind of substructure can be readily detected by performing PCA locally in the inversion regions. Using simulations, we demonstrated that the proposed method can be used to detect and genotype inversion polymorphisms using unphased genotype data. We applied our method to the phase III HapMap data and inferred the inversion genotypes of known inversion polymorphisms at 8p23.1 and 17q21.31. These inversion genotypes were validated by comparing with literature results and by checking Mendelian consistency using the family data whenever available. Based on the PCA-approach, we also performed a preliminary genome-wide scan for inversions using the HapMap data, which resulted in 2040 candidate inversions, 169 of which overlapped with previously reported inversions. Our method can be readily applied to the abundant SNP data, and is expected to play an important role in developing human genome maps of inversions and exploring associations between inversions and susceptibility of diseases. PMID:22808122

  13. Serum Folate Shows an Inverse Association with Blood Pressure in a Cohort of Chinese Women of Childbearing Age: A Cross-Sectional Study

    PubMed Central

    Shen, Minxue; Tan, Hongzhuan; Zhou, Shujin; Retnakaran, Ravi; Smith, Graeme N.; Davidge, Sandra T.; Trasler, Jacquetta; Walker, Mark C.; Wen, Shi Wu

    2016-01-01

    Background It has been reported that higher folate intake from food and supplementation is associated with decreased blood pressure (BP). The association between serum folate concentration and BP has been examined in few studies. We aim to examine the association between serum folate and BP levels in a cohort of young Chinese women. Methods We used the baseline data from a pre-conception cohort of women of childbearing age in Liuyang, China, for this study. Demographic data were collected by structured interview. Serum folate concentration was measured by immunoassay, and homocysteine, blood glucose, triglyceride and total cholesterol were measured through standardized clinical procedures. Multiple linear regression and principal component regression model were applied in the analysis. Results A total of 1,532 healthy normotensive non-pregnant women were included in the final analysis. The mean concentration of serum folate was 7.5 ± 5.4 nmol/L and 55% of the women presented with folate deficiency (< 6.8 nmol/L). Multiple linear regression and principal component regression showed that serum folate levels were inversely associated with systolic and diastolic BP, after adjusting for demographic, anthropometric, and biochemical factors. Conclusions Serum folate is inversely associated with BP in non-pregnant women of childbearing age with high prevalence of folate deficiency. PMID:27182603

  14. Molecular Characterization and Chromosomal Distribution of Galileo, Kepler and Newton, Three Foldback Transposable Elements of the Drosophila buzzatii Species Complex

    PubMed Central

    Casals, Ferran; Cáceres, Mario; Manfrin, Maura Helena; González, Josefa; Ruiz, Alfredo

    2005-01-01

    Galileo is a foldback transposable element that has been implicated in the generation of two polymorphic chromosomal inversions in Drosophila buzzatii. Analysis of the inversion breakpoints led to the discovery of two additional elements, called Kepler and Newton, sharing sequence and structural similarities with Galileo. Here, we describe in detail the molecular structure of these three elements, on the basis of the 13 copies found at the inversion breakpoints plus 10 additional copies isolated during this work. Similarly to the foldback elements described in other organisms, these elements have long inverted terminal repeats, which in the case of Galileo possess a complex structure and display a high degree of internal variability between copies. A phylogenetic tree built with their shared sequences shows that the three elements are closely related and diverged ∼10 million years ago. We have also analyzed the abundance and chromosomal distribution of these elements in D. buzzatii and other species of the repleta group by Southern analysis and in situ hybridization. Overall, the results suggest that these foldback elements are present in all the buzzatti complex species and may have played an important role in shaping their genomes. In addition, we show that recombination rate is the main factor determining the chromosomal distribution of these elements. PMID:15695364

  15. [Spectrum simulation based on data derived from red tide].

    PubMed

    Liu, Zhen-Yu; Cui, Ting-Wei; Yue, Jie; Jiang, Tao; Cao, Wen-Xi; Ma, Yi

    2011-11-01

    The present paper utilizes the absorption data of red tide water measured during the growing and dying course to retrieve imaginary part of the index of refraction based on Mie theory, carries out the simulation and analysis of average absorption efficiency factors, average backscattering efficiency factors and scattering phase function. The analysis of the simulation shows that Mie theory can be used to reproduce the absorption property of Chaetoceros socialis with an average error of 11%; the average backscattering efficiency factors depend on the value of absorption whose maximum value corresponds to the wavelength range from 400 to 700 nanometer; the average backscattering efficiency factors showed a maximum value on 17th with a low value during the outbreak of red tide and the minimum on 21th; the total scattering, weakly depending on the absorption, is proportional to the size parameters which represent the relative size of cell diameter with respect to the wavelength, while the angle scattering intensity is inversely proportional to wavelength.

  16. Bone health and risk factors of cardiovascular disease--a cross-sectional study in healthy young adults.

    PubMed

    Pirilä, Satu; Taskinen, Mervi; Turanlahti, Maila; Kajosaari, Merja; Mäkitie, Outi; Saarinen-Pihkala, Ulla M; Viljakainen, Heli

    2014-01-01

    Both osteoporosis and cardiovascular disease (CVD) are diseases that comprise a growing medical and economic burden in ageing populations. They share many risk factors, including ageing, low physical activity, and possibly overweight. We aimed to study associations between individual risk factors for CVD and bone mineral density (BMD) and turnover markers (BTMs) in apparently healthy cohort. A cross-sectional assessment of 155 healthy 32-year-old adults (74 males) was performed for skeletal status, CVD risk factors and lifestyle factors. We analysed serum osteocalcin, procollagen I aminoterminal propeptide (P1NP), collagen I carboxy-terminal telopeptide (ICTP) and urine collagen I aminoterminal telopeptide (U-NTX), as well as serum insulin, plasma glucose, triglyceride and HDL-cholesterol levels. BMD, fat and lean mass were assessed using DXA scanning. Associations were tested with partial correlations in crude and adjusted models. Bone status was compared between men with or without metabolic syndrome (defined according to the NCEP-ATPIII criteria) with multivariate analysis. Osteocalcin and P1NP correlated inversely with insulin (R = -0.243, P = 0.003 and R = -0.187, P = 0.021) and glucose (R = -0.213, P = 0.009 and R = -0.190, P = 0.019), but after controlling for fat mass and lifestyle factors, the associations attenuated with insulin (R = -0.162, P = 0.053 and R = -0.093, P = 0.266) and with glucose (R = -0.099, P = 0.240 and R = -0.133, P = 0.110), respectively. Whole body BMD associated inversely only with triglycerides in fully adjusted model. In men with metabolic syndrome, whole body BMD, osteocalcin and P1NP were lower compared to healthy men, but these findings disappeared in fully adjusted model. In young adults, inverse associations between BTM/BMD and risk factors of CVD appeared in crude models, but after adjusting for fat mass, no association continued to be present. In addition to fat mass, lifestyle factors, especially physical activity, modified the associations between CVD and bone characteristics. Prospective studies are needed to specify the role of mediators and lifestyle factors in the prevention of CVD and osteoporosis.

  17. Face Inversion Disproportionately Impairs the Perception of Vertical but Not Horizontal Relations between Features

    ERIC Educational Resources Information Center

    Goffaux, Valerie; Rossion, Bruno

    2007-01-01

    Upside-down inversion disrupts the processing of spatial relations between the features of a face, while largely preserving local feature analysis. However, recent studies on face inversion failed to observe a clear dissociation between relational and featural processing. To resolve these discrepancies and clarify how inversion affects face…

  18. Habitual dietary sodium intake is inversely associated with coronary flow reserve in middle-aged male twins.

    PubMed

    Eufinger, Silvia C; Votaw, John; Faber, Tracy; Ziegler, Thomas R; Goldberg, Jack; Bremner, J Douglas; Vaccarino, Viola

    2012-03-01

    Evidence links dietary sodium to hypertension and cardiovascular disease (CVD), but investigation of its influence on cardiovascular function is limited. We examined the relation between habitual dietary sodium and coronary flow reserve (CFR), which is a measure of overall coronary vasodilator capacity and microvascular function. We hypothesized that increased sodium consumption is associated with lower CFR. Habitual daily sodium intake for the previous 12 mo was measured in 286 male middle-aged twins (133 monozygotic and dizygotic pairs and 20 unpaired twins) by using the Willett food-frequency questionnaire. CFR was measured by positron emission tomography [N(13)]-ammonia, with quantitation of myocardial blood flow at rest and after adenosine stress. Mixed-effects regression analysis was used to assess the association between dietary sodium and CFR. An increase in dietary sodium of 1000 mg/d was associated with a 10.0% lower CFR (95% CI: -17.0%, -2.5%) after adjustment for demographic, lifestyle, nutritional, and CVD risk factors (P = 0.01). Across quintiles of sodium consumption, dietary sodium was inversely associated with CFR (P-trend = 0.03), with the top quintile (>1456 mg/d) having a 20% lower CFR than the bottom quintile (<732 mg /d). This association also persisted within pairs: a 1000-mg/d difference in dietary sodium between brothers was associated with a 10.3% difference in CFR after adjustment for potential confounders (P = 0.02). Habitual dietary sodium is inversely associated with CFR independent of CVD risk factors and shared familial and genetic factors. Our study suggests a potential novel mechanism for the adverse effects of dietary sodium on the cardiovascular system. This trial was registered at clinicaltrials.gov as NCT00017836.

  19. Habitual dietary sodium intake is inversely associated with coronary flow reserve in middle-aged male twins1234

    PubMed Central

    Eufinger, Silvia C; Votaw, John; Faber, Tracy; Ziegler, Thomas R; Goldberg, Jack; Bremner, J Douglas

    2012-01-01

    Background: Evidence links dietary sodium to hypertension and cardiovascular disease (CVD), but investigation of its influence on cardiovascular function is limited. Objective: We examined the relation between habitual dietary sodium and coronary flow reserve (CFR), which is a measure of overall coronary vasodilator capacity and microvascular function. We hypothesized that increased sodium consumption is associated with lower CFR. Design: Habitual daily sodium intake for the previous 12 mo was measured in 286 male middle-aged twins (133 monozygotic and dizygotic pairs and 20 unpaired twins) by using the Willett food-frequency questionnaire. CFR was measured by positron emission tomography [N13]-ammonia, with quantitation of myocardial blood flow at rest and after adenosine stress. Mixed-effects regression analysis was used to assess the association between dietary sodium and CFR. Results: An increase in dietary sodium of 1000 mg/d was associated with a 10.0% lower CFR (95% CI: −17.0%, −2.5%) after adjustment for demographic, lifestyle, nutritional, and CVD risk factors (P = 0.01). Across quintiles of sodium consumption, dietary sodium was inversely associated with CFR (P-trend = 0.03), with the top quintile (>1456 mg/d) having a 20% lower CFR than the bottom quintile (<732 mg /d). This association also persisted within pairs: a 1000-mg/d difference in dietary sodium between brothers was associated with a 10.3% difference in CFR after adjustment for potential confounders (P = 0.02). Conclusions: Habitual dietary sodium is inversely associated with CFR independent of CVD risk factors and shared familial and genetic factors. Our study suggests a potential novel mechanism for the adverse effects of dietary sodium on the cardiovascular system. This trial was registered at clinicaltrials.gov as NCT00017836. PMID:22258268

  20. Association between Polyphenol Intake and Hypertension in Adults and Older Adults: A Population-Based Study in Brazil

    PubMed Central

    Miranda, Andreia Machado; Steluti, Josiane; Fisberg, Regina Mara; Marchioni, Dirce Maria

    2016-01-01

    Background/Objective Hypertension is an important risk factor for cardiovascular disease, and diet has been identified as a modifiable factor for preventing and controlling hypertension. Besides, epidemiological studies have suggested an inverse association between polyphenol intake and cardiovascular diseases. The aim of this study was to evaluate the association between the intake of polyphenols and hypertension in a general population of Sao Paulo. Methods Data came from the ‘Health Survey of Sao Paulo (ISA-Capital)’ among 550 adults and older adults in Sao Paulo, Brazil. Diet was assessed by two 24-hour dietary recalls (24HR). Usual intakes were calculated using the Multiple Source Method. Polyphenol intake was calculated by matching food consumption data from the 24HR with the Phenol-Explorer database. The associations between the hypertension and tertiles of the total and classes of polyphenols intake were tested by multivariate logistic regression analysis. Results After multivariate adjustment for potential confounding factors the findings showed an inverse and linearly association between the hypertension and highest tertiles of tyrosols (OR = 0.33; 95%CI 0.18, 0.64), alkylphenols (OR = 0.45; 95%CI 0.23, 0.87), lignans (OR = 0.49; 95%CI 0.25, 0.98), as well as stilbenes (OR = 0.60; 95%CI 0.36, 0.98), and other polyphenols (OR = 0.33; 95%CI 0.14, 0.74). However, total polyphenol intake, and phenolic acids were significantly associated only in the middle tertile with hypertension and flavonoids were not significant associated. Conclusion There is an inverse and linearly association between the highest tertile of some classes of polyphenols, such as, tyrosols, alkylphenols, lignans, stilbenes, other polyphenols and hypertension. PMID:27792767

  1. Combining multiple imputation and meta-analysis with individual participant data

    PubMed Central

    Burgess, Stephen; White, Ian R; Resche-Rigon, Matthieu; Wood, Angela M

    2013-01-01

    Multiple imputation is a strategy for the analysis of incomplete data such that the impact of the missingness on the power and bias of estimates is mitigated. When data from multiple studies are collated, we can propose both within-study and multilevel imputation models to impute missing data on covariates. It is not clear how to choose between imputation models or how to combine imputation and inverse-variance weighted meta-analysis methods. This is especially important as often different studies measure data on different variables, meaning that we may need to impute data on a variable which is systematically missing in a particular study. In this paper, we consider a simulation analysis of sporadically missing data in a single covariate with a linear analysis model and discuss how the results would be applicable to the case of systematically missing data. We find in this context that ensuring the congeniality of the imputation and analysis models is important to give correct standard errors and confidence intervals. For example, if the analysis model allows between-study heterogeneity of a parameter, then we should incorporate this heterogeneity into the imputation model to maintain the congeniality of the two models. In an inverse-variance weighted meta-analysis, we should impute missing data and apply Rubin's rules at the study level prior to meta-analysis, rather than meta-analyzing each of the multiple imputations and then combining the meta-analysis estimates using Rubin's rules. We illustrate the results using data from the Emerging Risk Factors Collaboration. PMID:23703895

  2. Mediating effects of motor performance, cardiorespiratory fitness, physical activity, and sedentary behaviour on the associations of adiposity and other cardiometabolic risk factors with academic achievement in children.

    PubMed

    Haapala, Eero A; Lintu, Niina; Eloranta, Aino-Maija; Venäläinen, Taisa; Poikkeus, Anna-Maija; Ahonen, Timo; Lindi, Virpi; Lakka, Timo A

    2018-03-09

    We investigated the associations of cardiometabolic risk factors with academic achievement and whether motor performance, cardiorespiratory fitness, physical activity, or sedentary behaviour mediated these associations. Altogether 175 children 6-8 years-of-age participated in the study. We assessed body fat percentage (BF%), waist circumference, insulin, glucose, triglycerides, HDL cholesterol, and systolic and diastolic blood pressure, leptin, alanine aminotransferase, and gamma-glutamyltransferase (GGT). Reading fluency, reading comprehension, and arithmetic skills were assessed using standardized tests. Speed/agility, balance, and manual dexterity test results were used to calculate motor performance score and physical activity was assessed by combined heart rate and movement sensor and cardiorespiratory fitness by maximal cycle ergometer test. In boys, BF% was inversely associated with reading fluency (β = -0.262, P = 0.007) and reading comprehension (β = -0.216, P = 0.025). Motor performance mediated these associations. Leptin was inversely related to reading fluency (β = -0.272, P = 0.006) and reading comprehension (β = -0.287, P = 0.003). The inverse association of leptin with reading fluency was mediated by motor performance. In girls, GGT was inversely associated with reading fluency independent of confounders (β = -0.325, P = 0.007). The inverse association of BF% with academic achievement among boys was largely explained by motor performance. Leptin in boys and GGT in girls were inversely associated with academic achievement independent of confounding factors.

  3. Selection on Inversion Breakpoints Favors Proximity to Pairing Sensitive Sites in Drosophila melanogaster

    PubMed Central

    Corbett-Detig, Russell B.

    2016-01-01

    Chromosomal inversions are widespread among taxa, and have been implicated in a number of biological processes including adaptation, sex chromosome evolution, and segregation distortion. Consistent with selection favoring linkage between loci, it is well established that length is a selected trait of inversions. However, the factors that affect the distribution of inversion breakpoints remain poorly understood. “Sensitive sites” have been mapped on all euchromatic chromosome arms in Drosophila melanogaster, and may be a source of natural selection on inversion breakpoint positions. Briefly, sensitive sites are genomic regions wherein proximal structural rearrangements result in large reductions in local recombination rates in heterozygotes. Here, I show that breakpoints of common inversions are significantly more likely to lie within a cytological band containing a sensitive site than are breakpoints of rare inversions. Furthermore, common inversions for which neither breakpoint intersects a sensitive site are significantly longer than rare inversions, but common inversions whose breakpoints intersect a sensitive site show no evidence for increased length. I interpret these results to mean that selection favors inversions whose breakpoints disrupt synteny near to sensitive sites, possibly because these inversions suppress recombination in large genomic regions. To my knowledge this is the first evidence consistent with positive selection acting on inversion breakpoint positions. PMID:27343234

  4. Selection on Inversion Breakpoints Favors Proximity to Pairing Sensitive Sites in Drosophila melanogaster.

    PubMed

    Corbett-Detig, Russell B

    2016-09-01

    Chromosomal inversions are widespread among taxa, and have been implicated in a number of biological processes including adaptation, sex chromosome evolution, and segregation distortion. Consistent with selection favoring linkage between loci, it is well established that length is a selected trait of inversions. However, the factors that affect the distribution of inversion breakpoints remain poorly understood. "Sensitive sites" have been mapped on all euchromatic chromosome arms in Drosophila melanogaster, and may be a source of natural selection on inversion breakpoint positions. Briefly, sensitive sites are genomic regions wherein proximal structural rearrangements result in large reductions in local recombination rates in heterozygotes. Here, I show that breakpoints of common inversions are significantly more likely to lie within a cytological band containing a sensitive site than are breakpoints of rare inversions. Furthermore, common inversions for which neither breakpoint intersects a sensitive site are significantly longer than rare inversions, but common inversions whose breakpoints intersect a sensitive site show no evidence for increased length. I interpret these results to mean that selection favors inversions whose breakpoints disrupt synteny near to sensitive sites, possibly because these inversions suppress recombination in large genomic regions. To my knowledge this is the first evidence consistent with positive selection acting on inversion breakpoint positions. Copyright © 2016 by the Genetics Society of America.

  5. Does Sufficient Evidence Exist to Support a Causal Association between Vitamin D Status and Cardiovascular Disease Risk? An Assessment Using Hill’s Criteria for Causality

    PubMed Central

    Weyland, Patricia G.; Grant, William B.; Howie-Esquivel, Jill

    2014-01-01

    Serum 25-hydroxyvitamin D (25(OH)D) levels have been found to be inversely associated with both prevalent and incident cardiovascular disease (CVD) risk factors; dyslipidemia, hypertension and diabetes mellitus. This review looks for evidence of a causal association between low 25(OH)D levels and increased CVD risk. We evaluated journal articles in light of Hill’s criteria for causality in a biological system. The results of our assessment are as follows. Strength of association: many randomized controlled trials (RCTs), prospective and cross-sectional studies found statistically significant inverse associations between 25(OH)D levels and CVD risk factors. Consistency of observed association: most studies found statistically significant inverse associations between 25(OH)D levels and CVD risk factors in various populations, locations and circumstances. Temporality of association: many RCTs and prospective studies found statistically significant inverse associations between 25(OH)D levels and CVD risk factors. Biological gradient (dose-response curve): most studies assessing 25(OH)D levels and CVD risk found an inverse association exhibiting a linear biological gradient. Plausibility of biology: several plausible cellular-level causative mechanisms and biological pathways may lead from a low 25(OH)D level to increased risk for CVD with mediators, such as dyslipidemia, hypertension and diabetes mellitus. Experimental evidence: some well-designed RCTs found increased CVD risk factors with decreasing 25(OH)D levels. Analogy: the association between serum 25(OH)D levels and CVD risk is analogous to that between 25(OH)D levels and the risk of overall cancer, periodontal disease, multiple sclerosis and breast cancer. Conclusion: all relevant Hill criteria for a causal association in a biological system are satisfied to indicate a low 25(OH)D level as a CVD risk factor. PMID:25184368

  6. Association between Parkinson’s Disease and Cigarette Smoking, Rural Living, Well-Water Consumption, Farming and Pesticide Use: Systematic Review and Meta-Analysis

    PubMed Central

    Breckenridge, Charles B.; Berry, Colin; Chang, Ellen T.; Sielken, Robert L.; Mandel, Jack S.

    2016-01-01

    Objective Bradford Hill’s viewpoints were used to conduct a weight-of-the-evidence assessment of the association between Parkinson’s disease (PD) and rural living, farming and pesticide use. The results were compared with an assessment based upon meta-analysis. For comparison, we also evaluated the association between PD and cigarette smoking as a “positive control” because a strong inverse association has been described consistently in the literature. Methods PubMed was searched systematically to identify all published epidemiological studies that evaluated associations between Parkinson’s disease (PD) and cigarette smoking, rural living, well-water consumption, farming and the use of pesticides, herbicides, insecticides, fungicides or paraquat. Studies were categorized into two study quality groups (Tier 1 or Tier 2); data were abstracted and a forest plot of relative risks (RRs) was developed for each risk factor. In addition, when available, RRs were tabulated for more highly exposed individuals compared with the unexposed. Summary RRs for each risk factor were calculated by meta-analysis of Tier 1, Tier 2 and all studies combined, with sensitivity analyses stratified by other study characteristics. Indices of between-study heterogeneity and evidence of reporting bias were assessed. Bradford Hill’s viewpoints were used to determine if a causal relationship between PD and each risk factor was supported by the weight of the evidence. Findings There was a consistent inverse (negative) association between current cigarette smoking and PD risk. In contrast, associations between PD and rural living, well-water consumption, farming and the use of pesticides, herbicides, insecticides, fungicides or paraquat were less consistent when assessed quantitatively or qualitatively. Conclusion The weight of the evidence and meta-analysis support the conclusion that there is a causal relationship between PD risk and cigarette smoking, or some unknown factor correlated with cigarette smoking. There may be risk factors associated with rural living, farming, pesticide use or well-water consumption that are causally related to PD, but the studies to date have not identified such factors. To overcome the limitations of research in this area, future studies will have to better characterize the onset of PD and its relationship to rural living, farming and exposure to pesticides. PMID:27055126

  7. Nitrous oxide emissions estimated with the Carbon Tracker Lagrange regional inversion framework suggest the North American source comes predominantly from agricultural regions

    NASA Astrophysics Data System (ADS)

    Nevison, C. D.; Andrews, A. E.; Thoning, K. W.; Saikawa, E.; Dlugokencky, E. J.; Sweeney, C.; Benmergui, J. S.

    2016-12-01

    The Carbon Tracker Lagrange (CTL) regional inversion framework is used to estimate North American nitrous oxide (N2O) emissions of 1.6 ± 0.4 Tg N/yr over 2008-2013. More than half of the North American emissions are estimated to come from the central agricultural belt, extending from southern Canada to Texas, and are strongest in spring and early summer, consistent with a nitrogen fertilizer-driven source. The estimated N2O flux from the Midwestern corn/soybean belt and the more northerly wheat belt corresponds to 5% of synthetic + organic N fertilizer applied to those regions. While earlier regional atmospheric inversion studies have suggested that global inventories such as EDGAR may be underestimating U.S. anthropogenic N2O emissions by a factor of 3 or more, our results, integrated over a full calendar year, are generally consistent with those inventories and with global inverse model results and budget constraints. The CTL framework is a Bayesian method based on footprints from the Stochastic Time-Inverted Lagrangian Transport (STILT) model applied to atmospheric N2O data from the National Oceanic and Atmospheric Administration (NOAA) Global Greenhouse Gas Reference Network, including surface, aircraft and tall tower platforms. The CTL inversion results are sensitive to the prescribed boundary condition or background value of N2O, which is estimated based on a new Empirical BackGround (EBG) product derived from STILT back trajectories applied to NOAA data. Analysis of the N2O EBG products suggests a significant, seasonally-varying influence on surface N2O data due to the stratospheric influx of N2O-depleted air. Figure 1. Posterior annual mean N2O emissions for 2010 estimated with the CTL regional inversion framework. The locations of NOAA surface and aircraft data used in the inversion are superimposed as black circles and grey triangles, respectively. Mobile surface sites are indicated with asterisks.

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sanquist, Thomas F.; Mahy, Heidi A.; Morris, Fred A.

    Understanding the issues surrounding public acceptance of homeland security systems is important for balancing security needs and potential civil liberties infringements. A psychometric survey was used to measure attitudes regarding homeland security systems. Psychometric rating data were obtained from 182 respondents on psychological attributes associated with 12 distinct types of homeland security systems. An inverse relationship was observed for the overall rating attributes of acceptability and risk of civil liberties infringement. Principal components analysis yielded a two factor solution, with the rating scale loading pattern suggesting factors of Perceived Effectiveness and Perceived Intrusiveness. These factors also showed an inverse relationship.more » The 12 different homeland security systems showed significantly different scores on the rating scales and PCA factors, which were used to rank the systems in terms of overall acceptability. Difference scores for the rating scales and PCA factors were used to compute a single acceptability value reflecting the relative weight of risks and benefits. Of the 12 systems studied, airport screening, canine detectors and radiation monitoring at borders were found to be relatively acceptable, i.e., the perceived benefits for homeland security outweighed the perceived risks to civil liberties. Students rated several systems as more effective than professionals, but the overall pattern of results for both types of subjects was similar. The data suggest that risk perception research and the psychometric paradigm are useful approaches for quantifying attitudes regarding homeland security systems and policies, and can be used to anticipate potentially significant public acceptance issues.« less

  9. Spatial distribution and cognitive correlates of gamma noise power in schizophrenia.

    PubMed

    Díez, A; Suazo, V; Casado, P; Martín-Loeches, M; Molina, V

    2013-06-01

    Brain activity is less organized in patients with schizophrenia than in healthy controls (HC). Noise power (scalp-recorded electroencephalographic activity unlocked to stimuli) may be of use for studying this disorganization. Method Fifty-four patients with schizophrenia (29 minimally treated and 25 stable treated), 23 first-degree relatives and 27 HC underwent clinical and cognitive assessments and an electroencephalographic recording during an oddball P300 paradigm to calculate noise power magnitude in the gamma band. We used a principal component analysis (PCA) to determine the factor structure of gamma noise power values across electrodes and the clinical and cognitive correlates of the resulting factors. The PCA revealed three noise power factors, roughly corresponding to the default mode network (DMN), frontal and occipital regions respectively. Patients showed higher gamma noise power loadings in the first factor when compared to HC and first-degree relatives. In the patients, frontal gamma noise factor scores related significantly and inversely to working memory and problem-solving performance. There were no associations with symptoms. There is an elevated gamma activity unrelated to task processing over regions coherent with the DMN topography in patients with schizophrenia. The same type of gamma activity over frontal regions is inversely related to performance in tasks with high involvement in these frontal areas. The idea of gamma noise as a possible biological marker for schizophrenia seems promising. Gamma noise might be of use in the study of underlying neurophysiological mechanisms involved in this disease.

  10. Nutrition habits, physical activity, and lung cancer: an authoritative review.

    PubMed

    Koutsokera, Alexandra; Kiagia, Maria; Saif, Muhammad W; Souliotis, Kyriakos; Syrigos, Kostas N

    2013-07-01

    Lung cancer is the leading cause of cancer death worldwide. Because of high incidence rates and low survival rates, it is important to study the risk factors that may help prevent the disease from developing. It has been well established that cigarette smoking is the most important risk factor for lung cancer. Nonetheless it is likely that there are other modifiable risk factors that would assist in the prevention of lung cancer. Research on factors such as nutrition and physical activity and their influence on lung cancer has been carried out for nearly 3 decades. A systematic review in the MEDLINE database of published studies was conducted, focusing on systematic reviews, meta-analyses, and large prospective studies. The association between physical activity and lung cancer has been conflicting. Among the researched studies, 10 showed an inverse association, whereas 11 reported no association. A meta-analysis that was conducted from 1996 to October 2003 showed that leisure physical activity (LPA) prevents lung cancer. Data from 11 cohort and case-control studies showed an inverse relationship between fruit and vegetable consumption and lung cancer. Evidence from case-control studies suggests a positive association between meat intake and risk of lung cancer, although several more recent studies have presented doubts about these findings. The possible association of physical activity, nutrition, and the risk of lung cancer development remains controversial. Further prospective studies should be conducted to determine the potential influence of these 2 risk factors. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Factor analysis of the Mayo-Portland Adaptability Inventory: structure and validity.

    PubMed

    Bohac, D L; Malec, J F; Moessner, A M

    1997-07-01

    Principal-components (PC) factor analysis of the Mayo-Portland Adaptability Inventory (MPAI) was conducted using a sample of outpatients (n = 189) with acquired brain injury (ABI) to evaluate whether outcome after ABI is multifactorial or unifactorial in nature. An eight-factor model was derived which explained 64-4% of the total variance. The eight factors were interpreted as representing Activities of Daily Living, Social Initiation, Cognition, Impaired-Self-awareness/Distress, Social Skills/ Support, Independence, Visuoperceptual, and Psychiatric, respectively. Validation of the Cognition factor was supported when factor scores were correlated with various neuropsychological measures. In addition, 117 patient self-rating total scores were used to evaluate the Impaired Self-awareness/Distress factor. An inverse relationship was observed, supporting this factor's ability to capture the two-dimensional phenomena of diminished self-awareness or enhanced emotional distress. A new subscale structure is suggested, that may allow greater clinical utility in understanding how ABI manifests in patients, and may provide clinicians with a better structure for implementing treatment strategies to address specific areas of impairment and disability for specific patients. Additionally, more precise measurement of treatment outcomes may be afforded by this reorganization.

  12. A Generalized Approach for the Interpretation of Geophysical Well Logs in Ground-Water Studies - Theory and Application

    USGS Publications Warehouse

    Paillet, Frederick L.; Crowder, R.E.

    1996-01-01

    Quantitative analysis of geophysical logs in ground-water studies often involves at least as broad a range of applications and variation in lithology as is typically encountered in petroleum exploration, making such logs difficult to calibrate and complicating inversion problem formulation. At the same time, data inversion and analysis depend on inversion model formulation and refinement, so that log interpretation cannot be deferred to a geophysical log specialist unless active involvement with interpretation can be maintained by such an expert over the lifetime of the project. We propose a generalized log-interpretation procedure designed to guide hydrogeologists in the interpretation of geophysical logs, and in the integration of log data into ground-water models that may be systematically refined and improved in an iterative way. The procedure is designed to maximize the effective use of three primary contributions from geophysical logs: (1) The continuous depth scale of the measurements along the well bore; (2) The in situ measurement of lithologic properties and the correlation with hydraulic properties of the formations over a finite sample volume; and (3) Multiple independent measurements that can potentially be inverted for multiple physical or hydraulic properties of interest. The approach is formulated in the context of geophysical inversion theory, and is designed to be interfaced with surface geophysical soundings and conventional hydraulic testing. The step-by-step procedures given in our generalized interpretation and inversion technique are based on both qualitative analysis designed to assist formulation of the interpretation model, and quantitative analysis used to assign numerical values to model parameters. The approach bases a decision as to whether quantitative inversion is statistically warranted by formulating an over-determined inversion. If no such inversion is consistent with the inversion model, quantitative inversion is judged not possible with the given data set. Additional statistical criteria such as the statistical significance of regressions are used to guide the subsequent calibration of geophysical data in terms of hydraulic variables in those situations where quantitative data inversion is considered appropriate.

  13. Inverse scattering transform for the time dependent Schrödinger equation with applications to the KPI equation

    NASA Astrophysics Data System (ADS)

    Zhou, Xin

    1990-03-01

    For the direct-inverse scattering transform of the time dependent Schrödinger equation, rigorous results are obtained based on an opertor-triangular-factorization approach. By viewing the equation as a first order operator equation, similar results as for the first order n x n matrix system are obtained. The nonlocal Riemann-Hilbert problem for inverse scattering is shown to have solution.

  14. Comparing multiple statistical methods for inverse prediction in nuclear forensics applications

    DOE PAGES

    Lewis, John R.; Zhang, Adah; Anderson-Cook, Christine Michaela

    2017-10-29

    Forensic science seeks to predict source characteristics using measured observables. Statistically, this objective can be thought of as an inverse problem where interest is in the unknown source characteristics or factors ( X) of some underlying causal model producing the observables or responses (Y = g ( X) + error). Here, this paper reviews several statistical methods for use in inverse problems and demonstrates that comparing results from multiple methods can be used to assess predictive capability. Motivation for assessing inverse predictions comes from the desired application to historical and future experiments involving nuclear material production for forensics research inmore » which inverse predictions, along with an assessment of predictive capability, are desired.« less

  15. Comparing multiple statistical methods for inverse prediction in nuclear forensics applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lewis, John R.; Zhang, Adah; Anderson-Cook, Christine Michaela

    Forensic science seeks to predict source characteristics using measured observables. Statistically, this objective can be thought of as an inverse problem where interest is in the unknown source characteristics or factors ( X) of some underlying causal model producing the observables or responses (Y = g ( X) + error). Here, this paper reviews several statistical methods for use in inverse problems and demonstrates that comparing results from multiple methods can be used to assess predictive capability. Motivation for assessing inverse predictions comes from the desired application to historical and future experiments involving nuclear material production for forensics research inmore » which inverse predictions, along with an assessment of predictive capability, are desired.« less

  16. Validation of Temperature Histories for Structural Steel Welds Using Estimated Heat-Affected-Zone Edges

    DTIC Science & Technology

    2016-10-12

    used parametrically for inverse thermal analysis of welds corresponding to other welding processes whose process conditions are within similar...regimes. The present study applies an inverse thermal analysis procedure that uses three-dimensional constraint conditions whose two-dimensional...Memorandum Report 63-0000-00 Office of Naval Research One Liberty Center 875 North Randolph Street, Suite 1425 Arlington, VA 22203-1995 ONR Inverse

  17. Micro-heterogeneity versus clustering in binary mixtures of ethanol with water or alkanes.

    PubMed

    Požar, Martina; Lovrinčević, Bernarda; Zoranić, Larisa; Primorać, Tomislav; Sokolić, Franjo; Perera, Aurélien

    2016-08-24

    Ethanol is a hydrogen bonding liquid. When mixed in small concentrations with water or alkanes, it forms aggregate structures reminiscent of, respectively, the direct and inverse micellar aggregates found in emulsions, albeit at much smaller sizes. At higher concentrations, micro-heterogeneous mixing with segregated domains is found. We examine how different statistical methods, namely correlation function analysis, structure factor analysis and cluster distribution analysis, can describe efficiently these morphological changes in these mixtures. In particular, we explain how the neat alcohol pre-peak of the structure factor evolves into the domain pre-peak under mixing conditions, and how this evolution differs whether the co-solvent is water or alkane. This study clearly establishes the heuristic superiority of the correlation function/structure factor analysis to study the micro-heterogeneity, since cluster distribution analysis is insensitive to domain segregation. Correlation functions detect the domains, with a clear structure factor pre-peak signature, while the cluster techniques detect the cluster hierarchy within domains. The main conclusion is that, in micro-segregated mixtures, the domain structure is a more fundamental statistical entity than the underlying cluster structures. These findings could help better understand comparatively the radiation scattering experiments, which are sensitive to domains, versus the spectroscopy-NMR experiments, which are sensitive to clusters.

  18. 2D joint inversion of CSAMT and magnetic data based on cross-gradient theory

    NASA Astrophysics Data System (ADS)

    Wang, Kun-Peng; Tan, Han-Dong; Wang, Tao

    2017-06-01

    A two-dimensional forward and backward algorithm for the controlled-source audio-frequency magnetotelluric (CSAMT) method is developed to invert data in the entire region (near, transition, and far) and deal with the effects of artificial sources. First, a regularization factor is introduced in the 2D magnetic inversion, and the magnetic susceptibility is updated in logarithmic form so that the inversion magnetic susceptibility is always positive. Second, the joint inversion of the CSAMT and magnetic methods is completed with the introduction of the cross gradient. By searching for the weight of the cross-gradient term in the objective function, the mutual influence between two different physical properties at different locations are avoided. Model tests show that the joint inversion based on cross-gradient theory offers better results than the single-method inversion. The 2D forward and inverse algorithm for CSAMT with source can effectively deal with artificial sources and ensures the reliability of the final joint inversion algorithm.

  19. Using emulsion inversion in industrial processes.

    PubMed

    Salager, Jean-Louis; Forgiarini, Ana; Márquez, Laura; Peña, Alejandro; Pizzino, Aldo; Rodriguez, María P; Rondón-González, Marianna

    2004-05-20

    Emulsion inversion is a complex phenomenon, often perceived as an instability that is essentially uncontrollable, although many industrial processes make use of it. A research effort that started 2 decades ago has provided the two-dimensional and three-dimensional description, the categorization and the theoretical interpretation of the different kinds of emulsion inversion. A clear-cut phenomenological approach is currently available for understanding its characteristics, the factors that influence it and control it, the importance of fine-tuning the emulsification protocol, and the crucial occurrence of organized structures such as liquid crystals or multiple emulsions. The current know-how is used to analyze some industrial processes involving emulsion inversion, e.g. the attainment of a fine nutrient or cosmetic emulsion by temperature or formulation-induced transitional inversion, the preparation of a silicone oil emulsion by catastrophic phase inversion, the manufacture of a viscous polymer latex by combined inversion and the spontaneous but enigmatic inversion of emulsions used in metal working operations such as lathing or lamination.

  20. Sensitivity Analysis of the Sheet Metal Stamping Processes Based on Inverse Finite Element Modeling and Monte Carlo Simulation

    NASA Astrophysics Data System (ADS)

    Yu, Maolin; Du, R.

    2005-08-01

    Sheet metal stamping is one of the most commonly used manufacturing processes, and hence, much research has been carried for economic gain. Searching through the literatures, however, it is found that there are still a lots of problems unsolved. For example, it is well known that for a same press, same workpiece material, and same set of die, the product quality may vary owing to a number of factors, such as the inhomogeneous of the workpice material, the loading error, the lubrication, and etc. Presently, few seem able to predict the quality variation, not to mention what contribute to the quality variation. As a result, trial-and-error is still needed in the shop floor, causing additional cost and time delay. This paper introduces a new approach to predict the product quality variation and identify the sensitive design / process parameters. The new approach is based on a combination of inverse Finite Element Modeling (FEM) and Monte Carlo Simulation (more specifically, the Latin Hypercube Sampling (LHS) approach). With an acceptable accuracy, the inverse FEM (also called one-step FEM) requires much less computation load than that of the usual incremental FEM and hence, can be used to predict the quality variations under various conditions. LHS is a statistical method, through which the sensitivity analysis can be carried out. The result of the sensitivity analysis has clear physical meaning and can be used to optimize the die design and / or the process design. Two simulation examples are presented including drawing a rectangular box and drawing a two-step rectangular box.

  1. Predictors of chronic ankle instability: Analysis of peroneal reaction time, dynamic balance and isokinetic strength.

    PubMed

    Sierra-Guzmán, Rafael; Jiménez, Fernando; Abián-Vicén, Javier

    2018-05-01

    Previous studies have reported the factors contributing to chronic ankle instability, which could lead to more effective treatments. However, factors such as the reflex response and ankle muscle strength have not been taken into account in previous investigations. Fifty recreational athletes with chronic ankle instability and 55 healthy controls were recruited. Peroneal reaction time in response to sudden inversion, isokinetic evertor muscle strength and dynamic balance with the Star Excursion Balance Test and the Biodex Stability System were measured. The relationship between the Cumberland Ankle Instability Tool score and performance on each test was assessed and a backward multiple linear regression analysis was conducted. Participants with chronic ankle instability showed prolonged peroneal reaction time, poor performance in the Biodex Stability System and decreased reach distance in the Star Excursion Balance Test. No significant differences were found in eversion and inversion peak torque. Moderate correlations were found between the Cumberland Ankle Instability Tool score and the peroneal reaction time and performance on the Star Excursion Balance Test. Peroneus brevis reaction time and the posteromedial and lateral directions of the Star Excursion Balance Test accounted for 36% of the variance in the Cumberland Ankle Instability Tool. Dynamic balance deficits and delayed peroneal reaction time are present in participants with chronic ankle instability. Peroneus brevis reaction time and the posteromedial and lateral directions of the Star Excursion Balance Test were the main contributing factors to the Cumberland Ankle Instability Tool score. No clear strength impairments were reported in unstable ankles. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Low Sex Hormone-Binding Globulin Levels Associate with Prediabetes in Chinese Men Independent of Total Testosterone

    PubMed Central

    Han, Bing; Li, Qin; Chen, Yi; Zhu, Chunfang; Chen, Yingchao; Xia, Fangzhen; Cang, Zhen; Lu, Meng; Chen, Chi; Lin, Dongping; Lu, Yingli

    2016-01-01

    Objective The association ns between prediabetes and androgens have been rarely reported, especially in Chinese men. We aimed to investigate whether androgens were associated with the prevalence of prediabetes diagnosed with new American Diabetes Association criteria in Chinese men and then to assess which androgen value was the most relevant factor. Methods A total of 2654 men (52.6±13.4 years old) were selected. Serum total testosterone (TT), sex hormone-binding globulin (SHBG) and free testosterone (FT) were measured. Covariance analysis of different androgen values were performed in age subgroups. Multinomial logistic regression was used for the association of TT, SHBG and FT with prediabetes and diabetes, as well as prediabetes in age subgroups. Results According to ADA new criteria, normoglycemia, prediabetes, and diabetes were diagnosed in 1405, 907 and 342 men, respectively. In covariance analysis, SHBG of prediabetes were found lower than that of normoglycemia but higher than that of diabetes (P <0.05). In multinomial logistic regression, serum TT and SHBG were inversely associated with prediabetes and diabetes. While, after full adjustment for age, residence area, economic status, waist circumference, metabolic factors, other two androgen values and HOMA-IR, only the associations of SHBG with prevalence of prediabetes and diabetes persisted statistically significant, especially in the elderly with prediabetes (all P for trend <0.05). Conclusions Serum androgen was inversely associated with prediabetes and diabetes in Chinese men. Low serum SHBG was the most relevant factor for prediabetes and diabetes. Whether it is an independent predictor for incident prediabetes in Chinese men needs further explorations. PMID:27583401

  3. Factors associated to infant mortality in Sub-Saharan Africa

    PubMed Central

    Ester, Pablo Viguera; Torres, Alberto; Freire, José M.; Hernández, Valentín; Gil, Ángel

    2011-01-01

    Half of the 10 million children who die annually in the world are from Sub-Saharan Africa (SSA). The reasons are known, but lack of will and resources avoid the development of sustainable policies. Associated factors to the high infant mortality rate (IMR) in SSA have been investigated in this research. An ecological multi-group study was designed comparing rates within SSA. The dependent variable is the IMR and health services, economic and development indicators are the independent variables. Information and data sources were WHO, World Bank, UNICEF and UNDP (1997–2007). IMR mean value is 92.2 (per 1000 live births) and a relationship with several of the factors could be observed. In the bi-variate analysis direct relationship was observed with maternal mortality rate and an inverse relationship was observed with prenatal care coverage, births assisted by skilled health personnel, gross national income per capita, per capita government expenditure on health, social security expenditure, adult literacy rate, net primary school enrolment rate, population with access to safe drinking water (in urban and rural areas) and with population with access to basic sanitation in rural areas. In the multi-variate analysis IMR had an inverse relationship with children under 5 years with diarrhoea who receive oral re-hydration, with social security expenditure as percentage of general government expenditure on health and with per capita government expenditure on health. The situation in SSA would change if their inhabitants received education and information to demand more equitable polices and better investments from their governments. PMID:28299068

  4. DNA Methylation Analysis of the Angiotensin Converting Enzyme (ACE) Gene in Major Depression

    PubMed Central

    Zill, Peter; Baghai, Thomas C.; Schüle, Cornelius; Born, Christoph; Früstück, Clemens; Büttner, Andreas; Eisenmenger, Wolfgang; Varallo-Bedarida, Gabriella; Rupprecht, Rainer; Möller, Hans-Jürgen; Bondy, Brigitta

    2012-01-01

    Background The angiotensin converting enzyme (ACE) has been repeatedly discussed as susceptibility factor for major depression (MD) and the bi-directional relation between MD and cardiovascular disorders (CVD). In this context, functional polymorphisms of the ACE gene have been linked to depression, to antidepressant treatment response, to ACE serum concentrations, as well as to hypertension, myocardial infarction and CVD risk markers. The mostly investigated ACE Ins/Del polymorphism accounts for ∼40%–50% of the ACE serum concentration variance, the remaining half is probably determined by other genetic, environmental or epigenetic factors, but these are poorly understood. Materials and Methods The main aim of the present study was the analysis of the DNA methylation pattern in the regulatory region of the ACE gene in peripheral leukocytes of 81 MD patients and 81 healthy controls. Results We detected intensive DNA methylation within a recently described, functional important region of the ACE gene promoter including hypermethylation in depressed patients (p = 0.008) and a significant inverse correlation between the ACE serum concentration and ACE promoter methylation frequency in the total sample (p = 0.02). Furthermore, a significant inverse correlation between the concentrations of the inflammatory CVD risk markers ICAM-1, E-selectin and P-selectin and the degree of ACE promoter methylation in MD patients could be demonstrated (p = 0.01 - 0.04). Conclusion The results of the present study suggest that aberrations in ACE promoter DNA methylation may be an underlying cause of MD and probably a common pathogenic factor for the bi-directional relationship between MD and cardiovascular disorders. PMID:22808171

  5. Plasma phospholipid transfer protein activity is inversely associated with betaine in diabetic and non-diabetic subjects.

    PubMed

    Dullaart, R P F; Garcia, Erwin; Jeyarajah, Elias; Gruppen, Eke G; Connelly, Margery A

    2016-08-31

    The choline metabolite, betaine, plays a role in lipid metabolism, and may predict the development of cardiovascular disease and type 2 diabetes mellitus (T2DM). Phospholipid transfer protein (PLTP) and lecithin:cholesterol acyltransferase (LCAT) require phosphatidylcholine as substrate, raising the possibility that there is an intricate relationship of these protein factors with choline metabolism. Here we determined the relationships of PLTP and LCAT activity with betaine in subjects with and without T2DM. Plasma betaine (nuclear magnetic resonance spectroscopy), PLTP activity (liposome-vesicle HDL system), LCAT activity (exogenous substrate assay) and (apo)lipoproteins were measured in 65 type 2 diabetic (T2DM) and in 55 non-diabetic subjects. PLTP and LCAT activity were elevated in T2DM (p < 0.05), whereas the difference in betaine was not significant. In age-, sex- and diabetes status-controlled correlation analysis, betaine was inversely correlated with triglycerides and positively with HDL cholesterol (p < 0.05 to 0.01). PLTP and LCAT activity were positively correlated with triglycerides and inversely with HDL cholesterol (p < 0.05 to 0.001). PLTP (r = -0.245, p = 0.006) and LCAT activity (r = -0.195, p = 0.035) were correlated inversely with betaine. The inverse association of PLTP activity with betaine remained significant after additional adjustment for body mass index and lipoprotein variables (β = -0.179, p = 0.034), whereas its association with LCAT activity lost significance (β = -0.056, p = 0.44). Betaine may influence lipoprotein metabolism via an effect on PLTP activity.

  6. Reexamination of Total Fluid Intake and Bladder Cancer in the Health Professionals Follow-Up Study Cohort

    PubMed Central

    Zhou, Jiachen; Smith, Scott; Giovannucci, Edward; Michaud, Dominique S.

    2012-01-01

    It has been hypothesized that high fluid intake may reduce contact time between carcinogens and bladder epithelium and consequently reduce carcinogenesis. Epidemiologic studies examining fluid intake and bladder cancer have been extremely inconsistent, ranging from strong inverse to strong positive associations. The authors reevaluated the association between fluid intake and bladder cancer among 47,909 participants in the prospective Health Professionals Follow-up Study over a period of 22 years. During follow-up (1986–2008), 823 incident bladder cancer cases were diagnosed. Information on fluid intake was collected by using the food frequency questionnaire at baseline and every 4 years thereafter. Cox proportional hazard regression analysis was used to adjust for risk factors for bladder cancer. Total fluid intake was inversely associated with bladder cancer when the analysis was based on the baseline diet (relative risk = 0.76, 95% confidence interval: 0.60, 0.97), comparing the highest total daily fluid intake quintile (>2,531 mL/day) with the lowest quintile (<1,290 mL/day) (Ptrend = 0.01). However, no association was detected when the analysis was based on recent diet or cumulative updated diet. The updated analysis for total fluid intake and bladder cancer was attenuated compared with the original findings from the first 10-year follow-up period. PMID:22355034

  7. Inverse association of des-acyl ghrelin with worksite blood pressure in overweight/obese male workers.

    PubMed

    Narisada, Akihiko; Hasegawa, Tomomi; Nakahigashi, Maki; Hirobe, Takaaki; Ikemoto, Tatsunori; Ushida, Takahiro; Kobayashi, Fumio

    2015-05-01

    Job strain, defined as a combination of high job demands and low job control, has been reported to elevate blood pressure (BP) during work. Meanwhile, a recent experimental study showed that ghrelin blunted the BP response to such mental stress. In the present study, we examined the hypothesis that des-acyl ghrelin may have some beneficial effects on worksite BP through modulating the BP response to work-related mental stress, i.e., job strain. Subjects were 34 overweight/obese male day-shift workers (mean age 41.7 ± 6.7 years). No subjects had received any anti-hypertensive medication. A 24-h ambulatory BP monitoring was recorded every 30 min on a regular working day. The average BP was calculated for Work BP, Morning BP, and Home BP. Job strain was assessed using the short version of the Japanese Job Content Questionnaire. Des-acyl ghrelin showed significant inverse correlations with almost all BPs except Morning SBP, Morning DBP, and Home DBP. In multiple regression analysis, des-acyl ghrelin inversely correlated with Work SBP after adjusting for confounding factors. Des-acyl ghrelin was also negatively associated with BP changes from Sleep to Morning, Sleep to Work, and Sleep to Home. Des-acyl ghrelin was inversely associated with Worksite BP, suggesting a unique beneficial effect of des-acyl ghrelin on Worksite BP in overweight/obese male day-shift workers.

  8. Myoelectric stimulation on peroneal muscles resists simulated ankle sprain motion.

    PubMed

    Fong, Daniel Tik-Pui; Chu, Vikki Wing-Shan; Chan, Kai-Ming

    2012-07-26

    The inadequate reaction time of the peroneal muscles in response to an incorrect foot contact event has been proposed as one of the etiological factors contributing to ankle joint inversion injury. Thus, the current study aimed to investigate the efficacy of a myoelectric stimulation applied to the peroneal muscles in the prevention of a simulated ankle inversion trauma. Ten healthy male subjects performed simulated inversion and supination tests on a pair of mechanical sprain simulators. An electrical signal was delivered to the peroneal muscles of the subjects through a pair of electrode pads. The start of the stimulus was synchronized with the drop of the sprain simulator's platform. In order to determine the maximum delay time which the stimulus could still resist the simulated ankle sprain motion, different delay time were test (0, 5, 10, and 15ms). Together with the control trial (no stimulus), there were 5 testing conditions for both simulated inversion and supination test. The effect was quantified by the drop in maximum ankle tilting angle and angular velocity, as determined by a motion analysis system with a standard laboratory procedure. Results showed that the myoelectric stimulation was effective in all conditions except the one with myoelectric stimulus delayed for 15ms in simulated supination test. It is concluded that myoelectric stimulation on peroneal muscles could resist an ankle spraining motion. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Protective Factors in American Indian Communities and Adolescent Violence

    PubMed Central

    Pu, Jia; Chewning, Betty; St. Clair, Iyekiyapiwin Darlene; Kokotailo, Patricia K; Lacourt, Jeanne; Wilson, Dale

    2014-01-01

    Purpose With their distinct cultural heritage and rural boundaries, American Indian reservation communities offer a unique opportunity to explore protective factors that help buffer adolescents from potential risk behaviors such as violence. Prior published research on Indian communities has not explored three potential protective factors for violence - parental monitoring of adolescents and friends, adolescents’ self-efficacy to avoid fighting, and adolescents’ interest in learning more about their traditional culture. This paper explores the relationship between these factors and reduced risk of reported violence. Methods In 1998, 630 American Indian students in grades 6–12 were surveyed in five Midwestern, rural Indian reservation schools. Path analysis was used to identify the direct and indirect association of the three potential protective factors with reduced violence behavior. Results There were significant gender differences both in perceived parental monitoring and in adolescents’ self-efficacy. For female adolescents, parental monitoring had the strongest inverse relationship with female adolescents’ involvement in violence. Female adolescents’ self-efficacy and their interest in learning more about their culture were also inversely associated with violence and therefore potentially important protectors. Male adolescents who reported more interest in learning the tribe’s culture had better self-efficacy to avoid violence. However, self-efficacy did not successfully predict their reported involvement in peer violence. Conclusions These findings support exploring gender differences, parental monitoring, self-efficacy training as well as cultural elements in future violence intervention studies. Further investigation is needed to identify protective factors for risk behaviors among male adolescents and test the generalizability to non-reservation based adolescents. PMID:22926269

  10. The mobility of the Alverà landslide (Cortina d'Ampezzo, Italy)

    NASA Astrophysics Data System (ADS)

    Gasparetto, Paolo; Mosselman, Marnix; Van Asch, Theo W. J.

    1996-04-01

    The Alverà landslide is a slow moving earth flow (some cm per year) in the Italian Dolomites situated east of the town of Cortina d'Ampezzo. It shows a source area and an elongated track zone (transport zone) and a lobe or accumulation zone. In this paper the mobility of this slow moving earth flow is analysed over a 3 year period with daily observations of the groundwater level and displacement measurements to identify critical thresholds in the mobility of this landslide and to assess the temporal trend and variations in the viscosity of the material. The total displacements in this 3 year period (July 1989 until October 1992) amount to 40 cm. Displacements of the Alverà landslide have been measured with deformometers and inclinometers. The analysis of the groundwater records in combination with displacements of the Alverà landslide over a period of three years shows at first sight an irregular response with respect to the onset of movement and the pore pressure fluctuations. In general, movements were detected at groundwater table elevations above the slip surface ranging from 0.7 to 0.9 of the total thickness of the landslide body. By using an expression derived by G. Salt, which puts in relation the inverse safety factor ( 1/F) and the logarithmic of the velocity (log s) by the constant of proportionality a (named "viscosity index" and which has the meaning of viscosity strength), it was found (for different periods of moving incidents and couples of 1/F and log v values) that the obtained trend of the calculated viscosity index values does not allow the critical evolution toward catastrophic movements of the landslide for a specific inverse safety factor value. The analysis of the moving incidents showed also a temporal variation of the viscosity index but there is not a decreasing trend of the viscous strength of the material. In other words the material does not show strain softening effects. There seems to be, however, a positive gradient relationship between the inverse safety factor and the viscosity index.

  11. The Relationship Between Non-Symbolic Multiplication and Division in Childhood

    PubMed Central

    McCrink, Koleen; Shafto, Patrick; Barth, Hilary

    2016-01-01

    Children without formal education in addition and subtraction are able to perform multi-step operations over an approximate number of objects. Further, their performance improves when solving approximate (but not exact) addition and subtraction problems that allow for inversion as a shortcut (e.g., a + b − b = a). The current study examines children’s ability to perform multi-step operations, and the potential for an inversion benefit, for the operations of approximate, non-symbolic multiplication and division. Children were trained to compute a multiplication and division scaling factor (*2 or /2, *4 or /4), and then tested on problems that combined two of these factors in a way that either allowed for an inversion shortcut (e.g., 8 * 4 / 4) or did not (e.g., 8 * 4 / 2). Children’s performance was significantly better than chance for all scaling factors during training, and they successfully computed the outcomes of the multi-step testing problems. They did not exhibit a performance benefit for problems with the a * b / b structure, suggesting they did not draw upon inversion reasoning as a logical shortcut to help them solve the multi-step test problems. PMID:26880261

  12. Unpredictability of fighter pilots' g duration tolerance by anthropometric and physiological characteristics.

    PubMed

    Park, Myunghwan; Yoo, Seunghoon; Seol, Hyeongju; Kim, Cheonyoung; Hong, Youngseok

    2015-04-01

    While the factors affecting fighter pilots' G level tolerance have been widely accepted, the factors affecting fighter pilots' G duration tolerance have not been well understood. Thirty-eight subjects wearing anti-G suits were exposed to sustained high G forces using a centrifuge. The subjects exerted AGSM and decelerated the centrifuge when they reached the point of loss of peripheral vision. The G profile consisted of a +2.3 G onset rate, +7.3 G single plateau, and -1.6 G offset rate. Each subject's G tolerance time was recorded and the relationship between the tolerance time and the subject's anthropometric and physiological factors were analyzed. The mean tolerance time of the 38 subjects was 31.6 s, and the min and max tolerance times were 20 s and 58 s, respectively. The correlation analysis indicated that none of the factors had statistically significant correlations with the subjects' G duration tolerance. Stepwise multiple regression analysis showed that G duration tolerance was not dependent on any personal factors of the subjects. After the values of personal factors were simplified into 0 or 1, the t-test analysis showed that subjects' heights were inversely correlated with G duration tolerance at a statistically significant level. However, a logistic regression analysis suggested that the effect of the height factor to a pilot's G duration tolerance was too weak to be used as a predictor of a pilot's G tolerance. Fighter pilots' G duration tolerance could not be predicted by pilots' anthropometric and physiological factors.

  13. Moment tensor inversion with three-dimensional sensor configuration of mining induced seismicity (Kiruna mine, Sweden)

    NASA Astrophysics Data System (ADS)

    Ma, Ju; Dineva, Savka; Cesca, Simone; Heimann, Sebastian

    2018-06-01

    Mining induced seismicity is an undesired consequence of mining operations, which poses significant hazard to miners and infrastructures and requires an accurate analysis of the rupture process. Seismic moment tensors of mining-induced events help to understand the nature of mining-induced seismicity by providing information about the relationship between the mining, stress redistribution and instabilities in the rock mass. In this work, we adapt and test a waveform-based inversion method on high frequency data recorded by a dense underground seismic system in one of the largest underground mines in the world (Kiruna mine, Sweden). A stable algorithm for moment tensor inversion for comparatively small mining induced earthquakes, resolving both the double-couple and full moment tensor with high frequency data, is very challenging. Moreover, the application to underground mining system requires accounting for the 3-D geometry of the monitoring system. We construct a Green's function database using a homogeneous velocity model, but assuming a 3-D distribution of potential sources and receivers. We first perform a set of moment tensor inversions using synthetic data to test the effects of different factors on moment tensor inversion stability and source parameters accuracy, including the network spatial coverage, the number of sensors and the signal-to-noise ratio. The influence of the accuracy of the input source parameters on the inversion results is also tested. Those tests show that an accurate selection of the inversion parameters allows resolving the moment tensor also in the presence of realistic seismic noise conditions. Finally, the moment tensor inversion methodology is applied to eight events chosen from mining block #33/34 at Kiruna mine. Source parameters including scalar moment, magnitude, double-couple, compensated linear vector dipole and isotropic contributions as well as the strike, dip and rake configurations of the double-couple term were obtained. The orientations of the nodal planes of the double-couple component in most cases vary from NNW to NNE with a dip along the ore body or in the opposite direction.

  14. Moment Tensor Inversion with 3D sensor configuration of Mining Induced Seismicity (Kiruna mine, Sweden)

    NASA Astrophysics Data System (ADS)

    Ma, Ju; Dineva, Savka; Cesca, Simone; Heimann, Sebastian

    2018-03-01

    Mining induced seismicity is an undesired consequence of mining operations, which poses significant hazard to miners and infrastructures and requires an accurate analysis of the rupture process. Seismic moment tensors of mining-induced events help to understand the nature of mining-induced seismicity by providing information about the relationship between the mining, stress redistribution and instabilities in the rock mass. In this work, we adapt and test a waveform-based inversion method on high frequency data recorded by a dense underground seismic system in one of the largest underground mines in the world (Kiruna mine, Sweden). Stable algorithm for moment tensor inversion for comparatively small mining induced earthquakes, resolving both the double couple and full moment tensor with high frequency data is very challenging. Moreover, the application to underground mining system requires accounting for the 3D geometry of the monitoring system. We construct a Green's function database using a homogeneous velocity model, but assuming a 3D distribution of potential sources and receivers. We first perform a set of moment tensor inversions using synthetic data to test the effects of different factors on moment tensor inversion stability and source parameters accuracy, including the network spatial coverage, the number of sensors and the signal-to-noise ratio. The influence of the accuracy of the input source parameters on the inversion results is also tested. Those tests show that an accurate selection of the inversion parameters allows resolving the moment tensor also in presence of realistic seismic noise conditions. Finally, the moment tensor inversion methodology is applied to 8 events chosen from mining block #33/34 at Kiruna mine. Source parameters including scalar moment, magnitude, double couple, compensated linear vector dipole and isotropic contributions as well as the strike, dip, rake configurations of the double couple term were obtained. The orientations of the nodal planes of the double-couple component in most cases vary from NNW to NNE with a dip along the ore body or in the opposite direction.

  15. Role of Retinocortical Processing in Spatial Vision

    DTIC Science & Technology

    1989-06-01

    its inverse transform . These are even- symmetric functions. Odd-symmetric Gabor functions would also be required for image coding (Daugman, 1987), but...spectrum square; thus its horizontal and vertical scale factors may differ by a power of 2. Since the inverse transform undoes this distor- tion, it has...FIGURE 3 STANDARD FORM OF EVEN GABOR FILTER 7 order to inverse - transform correctly. We used Gabor functions with the standard shape of Daugman’s "polar

  16. An approach to quantum-computational hydrologic inverse analysis

    DOE PAGES

    O'Malley, Daniel

    2018-05-02

    Making predictions about flow and transport in an aquifer requires knowledge of the heterogeneous properties of the aquifer such as permeability. Computational methods for inverse analysis are commonly used to infer these properties from quantities that are more readily observable such as hydraulic head. We present a method for computational inverse analysis that utilizes a type of quantum computer called a quantum annealer. While quantum computing is in an early stage compared to classical computing, we demonstrate that it is sufficiently developed that it can be used to solve certain subsurface flow problems. We utilize a D-Wave 2X quantum annealermore » to solve 1D and 2D hydrologic inverse problems that, while small by modern standards, are similar in size and sometimes larger than hydrologic inverse problems that were solved with early classical computers. Our results and the rapid progress being made with quantum computing hardware indicate that the era of quantum-computational hydrology may not be too far in the future.« less

  17. An approach to quantum-computational hydrologic inverse analysis.

    PubMed

    O'Malley, Daniel

    2018-05-02

    Making predictions about flow and transport in an aquifer requires knowledge of the heterogeneous properties of the aquifer such as permeability. Computational methods for inverse analysis are commonly used to infer these properties from quantities that are more readily observable such as hydraulic head. We present a method for computational inverse analysis that utilizes a type of quantum computer called a quantum annealer. While quantum computing is in an early stage compared to classical computing, we demonstrate that it is sufficiently developed that it can be used to solve certain subsurface flow problems. We utilize a D-Wave 2X quantum annealer to solve 1D and 2D hydrologic inverse problems that, while small by modern standards, are similar in size and sometimes larger than hydrologic inverse problems that were solved with early classical computers. Our results and the rapid progress being made with quantum computing hardware indicate that the era of quantum-computational hydrology may not be too far in the future.

  18. An approach to quantum-computational hydrologic inverse analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O'Malley, Daniel

    Making predictions about flow and transport in an aquifer requires knowledge of the heterogeneous properties of the aquifer such as permeability. Computational methods for inverse analysis are commonly used to infer these properties from quantities that are more readily observable such as hydraulic head. We present a method for computational inverse analysis that utilizes a type of quantum computer called a quantum annealer. While quantum computing is in an early stage compared to classical computing, we demonstrate that it is sufficiently developed that it can be used to solve certain subsurface flow problems. We utilize a D-Wave 2X quantum annealermore » to solve 1D and 2D hydrologic inverse problems that, while small by modern standards, are similar in size and sometimes larger than hydrologic inverse problems that were solved with early classical computers. Our results and the rapid progress being made with quantum computing hardware indicate that the era of quantum-computational hydrology may not be too far in the future.« less

  19. Relationship between strong-motion array parameters and the accuracy of source inversion and physical waves

    USGS Publications Warehouse

    Iida, M.; Miyatake, T.; Shimazaki, K.

    1990-01-01

    We develop general rules for a strong-motion array layout on the basis of our method of applying a prediction analysis to a source inversion scheme. A systematic analysis is done to obtain a relationship between fault-array parameters and the accuracy of a source inversion. Our study of the effects of various physical waves indicates that surface waves at distant stations contribute significantly to the inversion accuracy for the inclined fault plane, whereas only far-field body waves at both small and large distances contribute to the inversion accuracy for the vertical fault, which produces more phase interference. These observations imply the adequacy of the half-space approximation used throughout our present study and suggest rules for actual array designs. -from Authors

  20. Maternal Body Mass Index during Pregnancy and Offspring Neurocognitive Development.

    PubMed

    Craig, Wendy Y; Palomaki, Glenn E; Neveux, Louis M; Haddow, James E

    2013-03-01

    This hypothesis generating study explores second trimester maternal body mass index (BMI) during pregnancy and offspring neurocognitive development. Mothers and offspring served as controls in two earlier studies: 101 children at age two years and 118 children at age eight years. Frequency of maternal BMI ≥30 kg/m 2 increased from 10% in 1987-1990 to 30% in 2004-2006 ( P < 0.001); the socioeconomic gradient became more pronounced. At age two, one or more BSID-III (Bayley Scales of Infant Development, 3rd Edition) scores <85 were more frequent with higher maternal BMI ( P = 0.029); regression analysis suggested an inverse relationship between language scores and BMI ( P = 0.054). Among eight-year-olds, one or more WISC-III (Wechsler Intelligence Scale for Children, 3rd edition) scores <85 increased with maternal BMI ( P = 0.017); regression analysis showed an inverse relationship between performance subscale IQ score and BMI ( P = 0.023). Second trimester maternal obesity may be an independent risk factor for some aspects of children's neurocognitive development. Further study is indicated.

  1. Comparing mass balance and adjoint methods for inverse modeling of nitrogen dioxide columns for global nitrogen oxide emissions

    NASA Astrophysics Data System (ADS)

    Cooper, Matthew; Martin, Randall V.; Padmanabhan, Akhila; Henze, Daven K.

    2017-04-01

    Satellite observations offer information applicable to top-down constraints on emission inventories through inverse modeling. Here we compare two methods of inverse modeling for emissions of nitrogen oxides (NOx) from nitrogen dioxide (NO2) columns using the GEOS-Chem chemical transport model and its adjoint. We treat the adjoint-based 4D-Var modeling approach for estimating top-down emissions as a benchmark against which to evaluate variations on the mass balance method. We use synthetic NO2 columns generated from known NOx emissions to serve as "truth." We find that error in mass balance inversions can be reduced by up to a factor of 2 with an iterative process that uses finite difference calculations of the local sensitivity of NO2 columns to a change in emissions. In a simplified experiment to recover local emission perturbations, horizontal smearing effects due to NOx transport are better resolved by the adjoint approach than by mass balance. For more complex emission changes, or at finer resolution, the iterative finite difference mass balance and adjoint methods produce similar global top-down inventories when inverting hourly synthetic observations, both reducing the a priori error by factors of 3-4. Inversions of simulated satellite observations from low Earth and geostationary orbits also indicate that both the mass balance and adjoint inversions produce similar results, reducing a priori error by a factor of 3. As the iterative finite difference mass balance method provides similar accuracy as the adjoint method, it offers the prospect of accurately estimating top-down NOx emissions using models that do not have an adjoint.

  2. Information fusion in regularized inversion of tomographic pumping tests

    USGS Publications Warehouse

    Bohling, Geoffrey C.; ,

    2008-01-01

    In this chapter we investigate a simple approach to incorporating geophysical information into the analysis of tomographic pumping tests for characterization of the hydraulic conductivity (K) field in an aquifer. A number of authors have suggested a tomographic approach to the analysis of hydraulic tests in aquifers - essentially simultaneous analysis of multiple tests or stresses on the flow system - in order to improve the resolution of the estimated parameter fields. However, even with a large amount of hydraulic data in hand, the inverse problem is still plagued by non-uniqueness and ill-conditioning and the parameter space for the inversion needs to be constrained in some sensible fashion in order to obtain plausible estimates of aquifer properties. For seismic and radar tomography problems, the parameter space is often constrained through the application of regularization terms that impose penalties on deviations of the estimated parameters from a prior or background model, with the tradeoff between data fit and model norm explored through systematic analysis of results for different levels of weighting on the regularization terms. In this study we apply systematic regularized inversion to analysis of tomographic pumping tests in an alluvial aquifer, taking advantage of the steady-shape flow regime exhibited in these tests to expedite the inversion process. In addition, we explore the possibility of incorporating geophysical information into the inversion through a regularization term relating the estimated K distribution to ground penetrating radar velocity and attenuation distributions through a smoothing spline model. ?? 2008 Springer-Verlag Berlin Heidelberg.

  3. A Comparison between Model Base Hardconstrain, Bandlimited, and Sparse-Spike Seismic Inversion: New Insights for CBM Reservoir Modelling on Muara Enim Formation, South Sumatra

    NASA Astrophysics Data System (ADS)

    Mohamad Noor, Faris; Adipta, Agra

    2018-03-01

    Coal Bed Methane (CBM) as a newly developed resource in Indonesia is one of the alternatives to relieve Indonesia’s dependencies on conventional energies. Coal resource of Muara Enim Formation is known as one of the prolific reservoirs in South Sumatra Basin. Seismic inversion and well analysis are done to determine the coal seam characteristics of Muara Enim Formation. This research uses three inversion methods, which are: model base hard- constrain, bandlimited, and sparse-spike inversion. Each type of seismic inversion has its own advantages to display the coal seam and its characteristic. Interpretation result from the analysis data shows that the Muara Enim coal seam has 20 (API) gamma ray value, 1 (gr/cc) – 1.4 (gr/cc) from density log, and low AI cutoff value range between 5000-6400 (m/s)*(g/cc). The distribution of coal seam is laterally thinning northwest to southeast. Coal seam is seen biasedly on model base hard constraint inversion and discontinued on band-limited inversion which isn’t similar to the geological model. The appropriate AI inversion is sparse spike inversion which has 0.884757 value from cross plot inversion as the best correlation value among the chosen inversion methods. Sparse Spike inversion its self-has high amplitude as a proper tool to identify coal seam continuity which commonly appears as a thin layer. Cross-sectional sparse spike inversion shows that there are possible new boreholes in CDP 3662-3722, CDP 3586-3622, and CDP 4004-4148 which is seen in seismic data as a thick coal seam.

  4. Complex chromosomal rearrangement in a girl with psychomotor-retardation and a de novo inversion: inv(2)(p15;q24.2).

    PubMed

    Granot-Hershkovitz, Einat; Raas-Rothschild, Annick; Frumkin, Ayala; Granot, David; Silverstein, Shira; Abeliovich, Dvorah

    2011-08-01

    Cytogenetic analysis of DNA from a girl with severe psychomotor retardation revealed a de novo pericentric inversion of chromosome 2: 46,XX,inv(2)(p15q24.2). In order to elucidate the possible role of the inversion in the girl's abnormal phenotype, we analyzed the inversion breakpoints. FISH analysis revealed BAC clones spanning the breakpoints at 2p and 2q of the inversion. Southern blot hybridization with DNA probes from the BAC regions was used to refine the localization of the breakpoints, followed by inverse-PCR which enabled us to sequence the inversion breakpoints. We found a complex chromosomal rearrangement, including five breakpoints, four at 2q and one at 2p joined with minor insertions/deletions of a few bases. The breakpoint at 2p was within the NRXN1 gene that has previously been associated with autism, intellectual disabilities, and psychiatric disorders. In 2q, the breakpoints disrupted two genes, TANC1 and RBMS1; the phenotypic effect of these genes is not currently known. Copyright © 2011 Wiley-Liss, Inc.

  5. Significance of the model considering mixed grain-size for inverse analysis of turbidites

    NASA Astrophysics Data System (ADS)

    Nakao, K.; Naruse, H.; Tokuhashi, S., Sr.

    2016-12-01

    A method for inverse analysis of turbidity currents is proposed for application to field observations. Estimation of initial condition of the catastrophic events from field observations has been important for sedimentological researches. For instance, there are various inverse analyses to estimate hydraulic conditions from topography observations of pyroclastic flows (Rossano et al., 1996), real-time monitored debris-flow events (Fraccarollo and Papa, 2000), tsunami deposits (Jaffe and Gelfenbaum, 2007) and ancient turbidites (Falcini et al., 2009). These inverse analyses need forward models and the most turbidity current models employ uniform grain-size particles. The turbidity currents, however, are the best characterized by variation of grain-size distribution. Though there are numerical models of mixed grain-sized particles, the models have difficulty in feasibility of application to natural examples because of calculating costs (Lesshaft et al., 2011). Here we expand the turbidity current model based on the non-steady 1D shallow-water equation at low calculation costs for mixed grain-size particles and applied the model to the inverse analysis. In this study, we compared two forward models considering uniform and mixed grain-size particles respectively. We adopted inverse analysis based on the Simplex method that optimizes the initial conditions (thickness, depth-averaged velocity and depth-averaged volumetric concentration of a turbidity current) with multi-point start and employed the result of the forward model [h: 2.0 m, U: 5.0 m/s, C: 0.01%] as reference data. The result shows that inverse analysis using the mixed grain-size model found the known initial condition of reference data even if the condition where the optimization started is deviated from the true solution, whereas the inverse analysis using the uniform grain-size model requires the condition in which the starting parameters for optimization must be in quite narrow range near the solution. The uniform grain-size model often reaches to local optimum condition that is significantly different from true solution. In conclusion, we propose a method of optimization based on the model considering mixed grain-size particles, and show its application to examples of turbidites in the Kiyosumi Formation, Boso Peninsula, Japan.

  6. Low-cost capacitor voltage inverter for outstanding performance in piezoelectric energy harvesting.

    PubMed

    Lallart, Mickaël; Garbuio, Lauric; Richard, Claude; Guyomar, Daniel

    2010-01-01

    The purpose of this paper is to propose a new scheme for piezoelectric energy harvesting optimization. The proposed enhancement relies on a new topology for inverting the voltage across a single capacitor with reduced losses. The increase of the inversion quality allows a much more effective energy harvesting process using the so-called synchronized switch harvesting on inductor (SSHI) nonlinear technique. It is shown that the proposed architecture, based on a 2-step inversion, increases the harvested power by a theoretical factor up to square root of 2 (i.e., 40% gain) compared with classical SSHI, allowing an increase of the harvested power by a factor greater than 1000% compared with the standard energy harvesting technique for realistic values of inversion components. The proposed circuit, using only 4 digital switches and an intermediate capacitor, is also ultra-low power, because the inversion circuit does not require any external energy and the command signals are very simple.

  7. Myocardial Ischemia Induces SDF-1α Release in Cardiac Surgery Patients.

    PubMed

    Kim, Bong-Sung; Jacobs, Denise; Emontzpohl, Christoph; Goetzenich, Andreas; Soppert, Josefin; Jarchow, Mareike; Schindler, Lisa; Averdunk, Luisa; Kraemer, Sandra; Marx, Gernot; Bernhagen, Jürgen; Pallua, Norbert; Schlemmer, Heinz-Peter; Simons, David; Stoppe, Christian

    2016-06-01

    In the present observational study, we measured serum levels of the chemokine stromal cell-derived factor-1α (SDF-1α) in 100 patients undergoing cardiac surgery with cardiopulmonary bypass at seven distinct time points including preoperative values, myocardial ischemia, reperfusion, and the postoperative course. Myocardial ischemia triggered a marked increase of SDF-1α serum levels whereas cardiac reperfusion had no significant influence. Perioperative SDF-1α serum levels were influenced by patients' characteristics (e.g., age, gender, aspirin intake). In an explorative analysis, we observed an inverse association between SDF-1α serum levels and the incidence of organ dysfunction. In conclusion, time of myocardial ischemia was identified as the key stimulus for a significant upregulation of SDF-1α, indicating its role as a marker of myocardial injury. The inverse association between SDF-1α levels and organ dysfunction association encourages further studies to evaluate its organoprotective properties in cardiac surgery patients.

  8. Joint Loads and Cartilage Stress in Intact Joints of Military Transtibial Amputees: Enhancing Quality of Life

    DTIC Science & Technology

    2017-04-01

    crosstalk); analysis of tested subjects underway. 4) Developed analytical methods to obtain knee joint loads using EMG-driven inverse dynamics; analysis of...13/2018. Completion %: 40. Task 1.3: EMG-driven inverse dynamic (ID) analyses with OpenSim for amputee and control group subjects. Target date: 1...predicted by EMG-driven inverse dynamics. Two-three conference papers are being prepared for submission in February 2017. Other achievements. None

  9. Application of viscous-inviscid interaction methods to transonic turbulent flows

    NASA Technical Reports Server (NTRS)

    Lee, D.; Pletcher, R. H.

    1986-01-01

    Two different viscous-inviscid interaction schemes were developed for the analysis of steady, turbulent, transonic, separated flows over axisymmetric bodies. The viscous and inviscid solutions are coupled through the displacement concept using a transpiration velocity approach. In the semi-inverse interaction scheme, the viscous and inviscid equations are solved in an explicitly separate manner and the displacement thickness distribution is iteratively updated by a simple coupling algorithm. In the simultaneous interaction method, local solutions of viscous and inviscid equations are treated simultaneously, and the displacement thickness is treated as an unknown and is obtained as a part of the solution through a global iteration procedure. The inviscid flow region is described by a direct finite-difference solution of a velocity potential equation in conservative form. The potential equation is solved on a numerically generated mesh by an approximate factorization (AF2) scheme in the semi-inverse interaction method and by a successive line overrelaxation (SLOR) scheme in the simultaneous interaction method. The boundary-layer equations are used for the viscous flow region. The continuity and momentum equations are solved inversely in a coupled manner using a fully implicit finite-difference scheme.

  10. Design for a Crane Metallic Structure Based on Imperialist Competitive Algorithm and Inverse Reliability Strategy

    NASA Astrophysics Data System (ADS)

    Fan, Xiao-Ning; Zhi, Bo

    2017-07-01

    Uncertainties in parameters such as materials, loading, and geometry are inevitable in designing metallic structures for cranes. When considering these uncertainty factors, reliability-based design optimization (RBDO) offers a more reasonable design approach. However, existing RBDO methods for crane metallic structures are prone to low convergence speed and high computational cost. A unilevel RBDO method, combining a discrete imperialist competitive algorithm with an inverse reliability strategy based on the performance measure approach, is developed. Application of the imperialist competitive algorithm at the optimization level significantly improves the convergence speed of this RBDO method. At the reliability analysis level, the inverse reliability strategy is used to determine the feasibility of each probabilistic constraint at each design point by calculating its α-percentile performance, thereby avoiding convergence failure, calculation error, and disproportionate computational effort encountered using conventional moment and simulation methods. Application of the RBDO method to an actual crane structure shows that the developed RBDO realizes a design with the best tradeoff between economy and safety together with about one-third of the convergence speed and the computational cost of the existing method. This paper provides a scientific and effective design approach for the design of metallic structures of cranes.

  11. Crustal Structure Beneath Taiwan Using Frequency-band Inversion of Receiver Function Waveforms

    NASA Astrophysics Data System (ADS)

    Tomfohrde, D. A.; Nowack, R. L.

    Receiver function analysis is used to determine local crustal structure beneath Taiwan. We have performed preliminary data processing and polarization analysis for the selection of stations and events and to increase overall data quality. Receiver function analysis is then applied to data from the Taiwan Seismic Network to obtain radial and transverse receiver functions. Due to the limited azimuthal coverage, only the radial receiver functions are analyzed in terms of horizontally layered crustal structure for each station. In order to improve convergence of the receiver function inversion, frequency-band inversion (FBI) is implemented, in which an iterative inversion procedure with sequentially higher low-pass corner frequencies is used to stabilize the waveform inversion. Frequency-band inversion is applied to receiver functions at six stations of the Taiwan Seismic Network. Initial 20-layer crustal models are inverted for using prior tomographic results for the initial models. The resulting 20-1ayer models are then simplified to 4 to 5 layer models and input into an alternating depth and velocity frequency-band inversion. For the six stations investigated, the resulting simplified models provide an average estimate of 38 km for the Moho thickness surrounding the Central Range of Taiwan. Also, the individual station estimates compare well with the recent tomographic model of and the refraction results of Rau and Wu (1995) and the refraction results of Ma and Song (1997).

  12. [A case-control study of factors associated with repeat teen pregnancy based on a sample from a university maternity hospital].

    PubMed

    Silva, Andréa de Albuquerque Arruda; Coutinho, Isabela C; Katz, Leila; Souza, Alex Sandro Rolland

    2013-03-01

    Repeat teen pregnancy is a frequent issue and is considered an aggravating factor for increased maternal and fetal morbidity and social problems. The aim of the study was to identify factors associated with repeat teen pregnancy. A case-control study was conducted in 90 postpartum adolescents with more than one pregnancy (cases) and 90 adult women with a history of only one pregnancy during adolescence (controls). Statistical analysis used hierarchical logistic regression with 5% significance. Early sexual initiation (< 15 years), early age at first pregnancy (< 16 years), not raising the children themselves, and low family income (< one minimum wage) were associated with repeat teenage pregnancy, while partner change was inversely associated. Repeat teen pregnancy was mainly associated with reproductive and socioeconomic factors. Partner change appeared as a protective factor. Measures should be adopted during the postpartum period of teenage mothers in order to avoid repeat pregnancy.

  13. Adolescent religiosity and attitudes to HIV and AIDS in Ghana.

    PubMed

    Amoako-Agyeman, Kofi Nyame

    2012-11-01

    This study investigated the relationships between adolescent religiosity and attitudes to HIV/AIDS based on two major techniques of analysis, factor and regression analysis towards informing preventive school education strategies. Using cross-sectional data of 448 adolescents in junior high school, the study incorporated survey in a self-administered questionnaire and sought to identify underlying factors that affect pupils' responses, delineate the pattern of relationships between variables and select models which best explain and predict relationships among variables. A seven-factor solution described the 'attitude' construct including abstinence and protection, and six for 'religiosity'. The results showed relatively high levels of religiosity and a preference for private religiosity as opposed to organisational religiosity. The regression analysis produced significant relationships between factors of attitudes to HIV/AIDS and of religiosity. Adolescent with very high private religiosity are more likely to abstain from sex but less likely to use condoms once they initiate: protection is inversely related to religiosity. The findings suggest that religious-based adolescent interventions should focus on intrinsic religiosity. Additionally, increasing HIV prevention information and incorporating culturally relevant and socially acceptable values might lend support to improved adolescent school-based HIV/AIDS prevention programmes.

  14. Laplace-domain waveform modeling and inversion for the 3D acoustic-elastic coupled media

    NASA Astrophysics Data System (ADS)

    Shin, Jungkyun; Shin, Changsoo; Calandra, Henri

    2016-06-01

    Laplace-domain waveform inversion reconstructs long-wavelength subsurface models by using the zero-frequency component of damped seismic signals. Despite the computational advantages of Laplace-domain waveform inversion over conventional frequency-domain waveform inversion, an acoustic assumption and an iterative matrix solver have been used to invert 3D marine datasets to mitigate the intensive computing cost. In this study, we develop a Laplace-domain waveform modeling and inversion algorithm for 3D acoustic-elastic coupled media by using a parallel sparse direct solver library (MUltifrontal Massively Parallel Solver, MUMPS). We precisely simulate a real marine environment by coupling the 3D acoustic and elastic wave equations with the proper boundary condition at the fluid-solid interface. In addition, we can extract the elastic properties of the Earth below the sea bottom from the recorded acoustic pressure datasets. As a matrix solver, the parallel sparse direct solver is used to factorize the non-symmetric impedance matrix in a distributed memory architecture and rapidly solve the wave field for a number of shots by using the lower and upper matrix factors. Using both synthetic datasets and real datasets obtained by a 3D wide azimuth survey, the long-wavelength component of the P-wave and S-wave velocity models is reconstructed and the proposed modeling and inversion algorithm are verified. A cluster of 80 CPU cores is used for this study.

  15. Factors Associated with Excessive Body Fat in Men and Women: Cross-Sectional Data from Black South Africans Living in a Rural Community and an Urban Township

    PubMed Central

    Okop, Kufre Joseph; Levitt, Naomi; Puoane, Thandi

    2015-01-01

    Objective To determine the factors associated with excessive body fat among black African men and women living in rural and urban communities of South Africa. Methods This is a cross-sectional analysis of data from the Prospective Urban and Rural Epidemiology (PURE) study, Cape Town, South Africa conducted in 2009/2010. The study sample included 1220 participants (77.2% women) aged 35–70 years, for whom anthropometric measurements were obtained and risk factors documented through face-to-face interviews using validated international PURE study protocols. Sex-specific logistic regression models were used to evaluate socio-demographic, lifestyle and psychological factors associated with three excessive body fat indicators, namely body mass index (BMI), waist circumference (WC) and body fat percent (BF%). Results The prevalence of excessive body fat based on BF%, WC and BMI cut-offs were 96.0%, 86.1%, and 81.6% for women respectively, and 62.2%, 25.9%, and 36.0% for men respectively. The significant odds of excessive body fat among the currently married compared to unmarried were 4.1 (95% CI: 1.3–12.5) for BF% and 1.9 (95% CI: 1.3–2.9) for BMI among women; and 4.9 (95% CI: 2.6–9.6), 3.2 (95% CI: 1.6–6.4) and 3.6 (95% CI: 1.9–6.8) for BF%, WC and BMI respectively among men. Age ≤50 years (compared to age >50 years) was inversely associated with excessive BF% in men and women, and less-than-a-college education was inversely associated with excessive BMI and WC in men. Tobacco smoking was inversely associated with all three excessive adiposity indicators in women but not in men. Unemployment, depression, and stress did not predict excessive body fat in men or women. Conclusion The sex-differences in the socio-demographic and lifestyle factors associated with the high levels of excessive body fat in urban and rural women and men should be considered in packaging interventions to reduce obesity in these communities. PMID:26447880

  16. Correlation between serum 25-hydroxyvitamin D levels and carotid intima-media thickness in a Brazilian population descended from African slaves

    PubMed Central

    Monteiro, F.C.; Mandarino, N.R.; Santos, E.M.; Santos, A.M.; Salgado, J.V.; Brito, D.J.A.; Salgado, B.J.L.; Lages, J.S.; Castelo Branco, G.; Salgado, N.

    2018-01-01

    Hypovitaminosis D has been identified as a possible new cardiovascular risk factor. However, the results of studies correlating serum vitamin D levels with markers of subclinical atherosclerosis have been conflicting. The aim of this study was to correlate serum levels of 25-hydroxyvitamin D [25(OH)D] with carotid intima-media thickness (C-IMT) and conventional cardiovascular risk factors in Afro-descendants. A cross-sectional analysis was performed on a sample of 382 individuals from a cohort of descendants of African slaves, inhabitants of “Quilombola” communities, with a mean age of 57.79 ±15.3 years, 54.5% of whom were women. Socio-demographic and clinical data were collected and biochemical tests were performed, including serum levels of 25(OH)D by electrochemiluminescence and urinary albumin excretion, evaluated by the albumin/creatinine ratio (ACR) in a spot urine sample. All participants underwent high-resolution ultrasonography for C-IMT measurement. Hypovitaminosis D was defined as serum 25(OH)D levels <30 ng/mL. The mean serum 25(OH)D levels were 50.4±13.5 ng/mL, with a low prevalence of hypovitaminosis D (4.86%). By simple linear correlation, a significant inverse association between 25(OH)D levels and C-IMT (r=-0.174, P=0.001) was observed. However, after multiple linear regression analysis, the significance of the association between serum levels of 25(OH)D and C-IMT measurement was lost (β=-0.039, P=0.318) and only male gender, age, smoking, systolic blood pressure, glucose and low density lipoprotein (LDL)-cholesterol remained significantly associated with C-IMT. Levels of 25(OH)D were independently and positively associated with HDL-cholesterol and inversely associated with age and ACR. In conclusion, no independent association between 25(OH)D levels and C-IMT was observed in this population. On the other hand, there was an inverse association with albuminuria, a marker of endothelial lesion. PMID:29490002

  17. Maternal dietary patterns during pregnancy and risk of wheeze and eczema in Japanese infants aged 16-24 months: the Osaka Maternal and Child Health Study.

    PubMed

    Miyake, Yoshihiro; Okubo, Hitomi; Sasaki, Satoshi; Tanaka, Keiko; Hirota, Yoshio

    2011-11-01

    Maternal diet during pregnancy might influence the development of childhood allergic disorders.   This prospective study examined the relationship between maternal dietary patterns during pregnancy and the risk of wheeze and eczema in the offspring aged 16-24 months. Subjects were 763 mother-child pairs. Data on maternal intake during pregnancy were assessed with a diet history questionnaire. Dietary patterns were derived from factor analysis of 33 predefined food groups. Symptoms of wheeze and eczema were based on criteria of the International Study of Asthma and Allergies in Childhood. Adjustment was made for maternal age, gestation, residential municipality, family income, maternal and paternal education, maternal and paternal history of allergic disorders, changes in maternal diet in pregnancy, season at baseline, maternal smoking during pregnancy, baby's older siblings, sex, birth weight, age at the third survey, household smoking, and breastfeeding duration. Three dietary patterns were identified: 'healthy', characterized by high intake of green and yellow vegetables, seaweed, mushrooms, white vegetables, pulses, potatoes, fish, sea products, fruit, and shellfish; 'Western', characterized by high intake of vegetable oil, salt-containing seasonings, beef and pork, processed meat, eggs, chicken, and white vegetables; and 'Japanese', characterized by high intake of rice, miso soup, sea products, and fish. There was a tendency for an inverse exposure-response relationship between the maternal Western pattern during pregnancy and the risk of childhood wheeze by crude analysis. After adjustment for the confounding factors under study, the inverse relationship was strengthened: the adjusted OR between extreme quartiles was 0.59 (95% CI: 0.35-0.98, p for trend = 0.02). No such inverse association was observed for childhood eczema. Neither the maternal healthy pattern nor the Japanese pattern during pregnancy was related to childhood wheeze or eczema. The maternal Western pattern during pregnancy may be preventive against wheeze in the offspring. © 2011 John Wiley & Sons A/S.

  18. Correlation between serum 25-hydroxyvitamin D levels and carotid intima-media thickness in a Brazilian population descended from African slaves.

    PubMed

    Monteiro Júnior, F C; Mandarino, N R; Santos, E M; Santos, A M; Salgado, J V; Brito, D J A; Salgado, B J L; Lages, J S; Castelo Branco, G; Salgado Filho, N

    2018-01-01

    Hypovitaminosis D has been identified as a possible new cardiovascular risk factor. However, the results of studies correlating serum vitamin D levels with markers of subclinical atherosclerosis have been conflicting. The aim of this study was to correlate serum levels of 25-hydroxyvitamin D [25(OH)D] with carotid intima-media thickness (C-IMT) and conventional cardiovascular risk factors in Afro-descendants. A cross-sectional analysis was performed on a sample of 382 individuals from a cohort of descendants of African slaves, inhabitants of "Quilombola" communities, with a mean age of 57.79 ±15.3 years, 54.5% of whom were women. Socio-demographic and clinical data were collected and biochemical tests were performed, including serum levels of 25(OH)D by electrochemiluminescence and urinary albumin excretion, evaluated by the albumin/creatinine ratio (ACR) in a spot urine sample. All participants underwent high-resolution ultrasonography for C-IMT measurement. Hypovitaminosis D was defined as serum 25(OH)D levels <30 ng/mL. The mean serum 25(OH)D levels were 50.4±13.5 ng/mL, with a low prevalence of hypovitaminosis D (4.86%). By simple linear correlation, a significant inverse association between 25(OH)D levels and C-IMT (r=-0.174, P=0.001) was observed. However, after multiple linear regression analysis, the significance of the association between serum levels of 25(OH)D and C-IMT measurement was lost (β=-0.039, P=0.318) and only male gender, age, smoking, systolic blood pressure, glucose and low density lipoprotein (LDL)-cholesterol remained significantly associated with C-IMT. Levels of 25(OH)D were independently and positively associated with HDL-cholesterol and inversely associated with age and ACR. In conclusion, no independent association between 25(OH)D levels and C-IMT was observed in this population. On the other hand, there was an inverse association with albuminuria, a marker of endothelial lesion.

  19. Bilirubin concentration is positively associated with haemoglobin concentration and inversely associated with albumin to creatinine ratio among Indigenous Australians: eGFR Study.

    PubMed

    Hughes, J T; Barzi, F; Hoy, W E; Jones, G R D; Rathnayake, G; Majoni, S W; Thomas, M A B; Sinha, A; Cass, A; MacIsaac, R J; O'Dea, K; Maple-Brown, L J

    2017-12-01

    Low serum bilirubin concentrations are reported to be strongly associated with cardio-metabolic disease, but this relationship has not been reported among Indigenous Australian people who are known to be at high risk for diabetes and chronic kidney disease (CKD). serum bilirubin will be negatively associated with markers of chronic disease, including CKD and anaemia among Indigenous Australians. A cross-sectional analysis of 594 adult Aboriginal and Torres Strait Islander (TSI) people in good health or with diabetes and markers of CKD. Measures included urine albumin: creatinine ratio (ACR), estimated glomerular filtration rate (eGFR), haemoglobin (Hb) and glycated haemoglobin (HbA1c). Diabetes was defined by medical history, medications or HbA1c≥6.5% or ≥48mmol/mol. Anaemia was defined as Hb<130g/L or <120g/L in males and females respectively. A multivariate regression analysis examining factors independently associated with log-bilirubin was performed. Participants mean (SD) age was 45.1 (14.5) years, and included 62.5% females, 71.7% Aboriginal, 41.1% with diabetes, 16.7% with anaemia, 41% with ACR>3mg/mmol and 18.2% with eGFR<60mL/min/1.73m 2 . Median bilirubin concentration was lower in females than males (6 v 8μmol/L, p<0.001) and in Aboriginal than TSI participants (6 v 9.5μmol/L, p<0.001). Six factors explained 35% of the variance of log-bilirubin; Hb and cholesterol (both positively related) and ACR, triglycerides, Aboriginal ethnicity and female gender (all inversely related). Serum bilirubin concentrations were positively associated with Hb and total cholesterol, and inversely associated with ACR. Further research to determine reasons explaining lower bilirubin concentrations among Aboriginal compared with TSI participants are needed. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  20. Accounting for Selection Bias in Studies of Acute Cardiac Events.

    PubMed

    Banack, Hailey R; Harper, Sam; Kaufman, Jay S

    2018-06-01

    In cardiovascular research, pre-hospital mortality represents an important potential source of selection bias. Inverse probability of censoring weights are a method to account for this source of bias. The objective of this article is to examine and correct for the influence of selection bias due to pre-hospital mortality on the relationship between cardiovascular risk factors and all-cause mortality after an acute cardiac event. The relationship between the number of cardiovascular disease (CVD) risk factors (0-5; smoking status, diabetes, hypertension, dyslipidemia, and obesity) and all-cause mortality was examined using data from the Atherosclerosis Risk in Communities (ARIC) study. To illustrate the magnitude of selection bias, estimates from an unweighted generalized linear model with a log link and binomial distribution were compared with estimates from an inverse probability of censoring weighted model. In unweighted multivariable analyses the estimated risk ratio for mortality ranged from 1.09 (95% confidence interval [CI], 0.98-1.21) for 1 CVD risk factor to 1.95 (95% CI, 1.41-2.68) for 5 CVD risk factors. In the inverse probability of censoring weights weighted analyses, the risk ratios ranged from 1.14 (95% CI, 0.94-1.39) to 4.23 (95% CI, 2.69-6.66). Estimates from the inverse probability of censoring weighted model were substantially greater than unweighted, adjusted estimates across all risk factor categories. This shows the magnitude of selection bias due to pre-hospital mortality and effect on estimates of the effect of CVD risk factors on mortality. Moreover, the results highlight the utility of using this method to address a common form of bias in cardiovascular research. Copyright © 2018 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  1. Inversion structure and winter ozone distribution in the Uintah Basin, Utah, U.S.A.

    NASA Astrophysics Data System (ADS)

    Lyman, Seth; Tran, Trang

    2015-12-01

    The Uintah Basin in Utah, U.S.A. experiences high concentrations of ozone during some winters due to strong, multi-day temperature inversions that facilitate the buildup of pollution from local sources, including the oil and gas industry. Together, elevation of monitoring sites and proximity to oil and gas wells explain as much as 90% of spatial variability in surface ozone concentrations during inversion episodes (i.e., R2 = 0.90). Inversion conditions start earlier and last longer at lower elevations, at least in part because lower elevations are more insulated from winds aloft that degrade inversion conditions and dilute produced ozone. Surface air transport under inversions is dominated by light, diurnal upslope-downslope flow that limits net transport distances. Thus, different areas of the Basin are relatively isolated from each other, allowing spatial factors like elevation and proximity to sources to strongly influence ozone concentrations at individual sites.

  2. Evaluation of a Panel of Single-Nucleotide Polymorphisms in miR-146a and miR-196a2 Genomic Regions in Patients with Chronic Periodontitis.

    PubMed

    Venugopal, Priyanka; Lavu, Vamsi; RangaRao, Suresh; Venkatesan, Vettriselvi

    2017-04-01

    Periodontitis is an inflammatory disease caused by bacterial triggering of the host immune-inflammatory response, which in turn is regulated by microRNAs (miRNA). Polymorphisms in the miRNA pathways affect the expression of several target genes such as tumor necrosis factor-α and interleukins, which are associated with progression of disease. The objective of this study was to identify the association between the MiR-146a single nucleotide polymorphisms (SNPs) (rs2910164, rs57095329, and rs73318382), the MiR-196a2 (rs11614913) SNP and chronic periodontitis. Genotyping was performed for the MiR-146a (rs2910164, rs57095329, and rs73318382) and the MiR-196a2 (rs11614913) polymorphisms in 180 healthy controls and 190 cases of chronic periodontitis by the direct Sanger sequencing technique. The strength of the association between the polymorphisms and chronic periodontitis was evaluated using logistic regression analysis. Haplotype and linkage analyses among the polymorphisms was performed. Multifactorial dimensionality reduction was performed to determine epistatic interaction among the polymorphisms. The MiR-196a2 polymorphism revealed a significant inverse association with chronic periodontitis. Haplotype analysis of MiR-146a and MiR-196a2 polymorphisms revealed 13 different combinations, of which 5 were found to have an inverse association with chronic periodontitis. The present study has demonstrated a significant inverse association of MiR-196a2 polymorphism with chronic periodontitis.

  3. Laplace Transform Based Radiative Transfer Studies

    NASA Astrophysics Data System (ADS)

    Hu, Y.; Lin, B.; Ng, T.; Yang, P.; Wiscombe, W.; Herath, J.; Duffy, D.

    2006-12-01

    Multiple scattering is the major uncertainty for data analysis of space-based lidar measurements. Until now, accurate quantitative lidar data analysis has been limited to very thin objects that are dominated by single scattering, where photons from the laser beam only scatter a single time with particles in the atmosphere before reaching the receiver, and simple linear relationship between physical property and lidar signal exists. In reality, multiple scattering is always a factor in space-based lidar measurement and it dominates space- based lidar returns from clouds, dust aerosols, vegetation canopy and phytoplankton. While multiple scattering are clear signals, the lack of a fast-enough lidar multiple scattering computation tool forces us to treat the signal as unwanted "noise" and use simple multiple scattering correction scheme to remove them. Such multiple scattering treatments waste the multiple scattering signals and may cause orders of magnitude errors in retrieved physical properties. Thus the lack of fast and accurate time-dependent radiative transfer tools significantly limits lidar remote sensing capabilities. Analyzing lidar multiple scattering signals requires fast and accurate time-dependent radiative transfer computations. Currently, multiple scattering is done with Monte Carlo simulations. Monte Carlo simulations take minutes to hours and are too slow for interactive satellite data analysis processes and can only be used to help system / algorithm design and error assessment. We present an innovative physics approach to solve the time-dependent radiative transfer problem. The technique utilizes FPGA based reconfigurable computing hardware. The approach is as following, 1. Physics solution: Perform Laplace transform on the time and spatial dimensions and Fourier transform on the viewing azimuth dimension, and convert the radiative transfer differential equation solving into a fast matrix inversion problem. The majority of the radiative transfer computation goes to matrix inversion processes, FFT and inverse Laplace transforms. 2. Hardware solutions: Perform the well-defined matrix inversion, FFT and Laplace transforms on highly parallel, reconfigurable computing hardware. This physics-based computational tool leads to accurate quantitative analysis of space-based lidar signals and improves data quality of current lidar mission such as CALIPSO. This presentation will introduce the basic idea of this approach, preliminary results based on SRC's FPGA-based Mapstation, and how we may apply it to CALIPSO data analysis.

  4. Construction of Joule Thomson inversion curves for mixtures using equation of state

    NASA Astrophysics Data System (ADS)

    Patankar, A. S.; Atrey, M. D.

    2017-02-01

    The Joule-Thomson effect is at the heart of Joule-Thomson cryocoolers and gas liquefaction cycles. The effective harnessing of this phenomenon necessitates the knowledge of Joule-Thomson coefficient and the inversion curve. When the working fluid is a mixture, (in mix refrigerant Joule-Thomson cryocooler, MRJT) the phase diagrams, equations of state and inversion curves of multi-component systems become important. The lowest temperature attainable by such a cryocooler depends on the inversion characteristics of the mixture used. In this work the construction of differential Joule-Thomson inversion curves of mixtures using Redlich-Kwong, Soave-Redlich-Kwong and Peng-Robinson equations of state is investigated assuming single phase. It is demonstrated that inversion curves constructed for pure fluids can be improved by choosing an appropriate value of acentric factor. Inversion curves are used to predict maximum inversion temperatures of multicomponent systems. An application where this information is critical is a two-stage J-T cryocooler using a mixture as the working fluid, especially for the second stage. The pre-cooling temperature that the first stage is required to generate depends on the maximum inversion temperature of the second stage working fluid.

  5. Index-based dietary patterns and risk of lung cancer in the NIH-AARP diet and health study.

    PubMed

    Anic, G M; Park, Y; Subar, A F; Schap, T E; Reedy, J

    2016-01-01

    Dietary pattern analysis considers combinations of food intake and may offer a better measure to assess diet-cancer associations than examining individual foods or nutrients. Although tobacco exposure is the major risk factor for lung cancer, few studies have examined whether dietary patterns, based on preexisting dietary guidelines, influence lung cancer risk. After controlling for smoking, we examined associations between four diet quality indices-Healthy Eating Index-2010 (HEI-2010), Alternate Healthy Eating Index-2010 (AHEI-2010), alternate Mediterranean Diet score (aMED) and Dietary Approaches to Stop Hypertension (DASH)-and lung cancer risk in the NIH-AARP (National Institutes of Health-American Association of Retired Persons) Diet and Health study. Baseline dietary intake was assessed in 460 770 participants. Over a median of 10.5 years of follow-up, 9272 incident lung cancer cases occurred. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and confidence intervals (CIs). Comparing highest to lowest quintiles, HRs (95% CIs) for lung cancer were as follows: HEI-2010=0.83 (0.77-0.89), AHEI-2010=0.86 (0.80-0.92), aMED=0.85 (0.79-0.91) and DASH=0.84 (0.78-0.90). Among the individual components of the dietary indices, higher consumption of whole grains and fruits was significantly inversely associated with lung cancer risk for several of the diet indices. Total index score analyses stratified by smoking status showed inverse associations with lung cancer for former smokers; however, only HEI-2010 was inversely associated in current smokers and no index score was inversely associated among never smokers. Although smoking is the factor most strongly associated with lung cancer, this study adds to a growing body of evidence that diet may have a modest role in reducing lung cancer risk, especially among former smokers.

  6. Frequency of soup intake and amount of dietary fiber intake are inversely associated with plasma leptin concentrations in Japanese adults.

    PubMed

    Kuroda, Motonaka; Ohta, Masanori; Okufuji, Tatsuya; Takigami, Chieko; Eguchi, Masafumi; Hayabuchi, Hitomi; Ikeda, Masaharu

    2010-06-01

    Previous studies have shown that the intake of soup negatively correlates with the body mass index (BMI), suggesting that soup intake reduces the risk of obesity. In this study, to clarify the association of the intake of soup and various nutrients with plasma leptin concentration, a cross-sectional study on 504 Japanese adults aged 20-76 years (103 men and 401 women) was performed. The intake of soup and various nutrients was investigated by food frequency questionnaires. Plasma leptin concentration was measured in fasting blood by radioimmunoassay. The correlation was analyzed by multiple regression analysis. The average frequency of soup intake was 7.6 times/week. The average plasma leptin concentration was 7.76 ng/ml. After adjusting the confounding factors, the frequency of soup intake has a significant inverse association with plasma leptin concentration. Among the macronutrients, only dietary fiber intake negatively correlated with plasma leptin concentration after the adjustment for potential confounding factors. These results suggest that the intakes of soup and dietary fiber were negatively correlated with plasma leptin concentration in Japanese adults. Copyright 2010 Elsevier Ltd. All rights reserved.

  7. PubMed

    La Torre, Giuseppe; Verrengia, Giovanna; Saulle, Rossella; Kheiraoui, Flavia; Mannocci, Alice

    2017-06-28

    To identify the determinants of the regional differences in work injuries and mortality rates in Italy. Several linear regression models were built assessing the association between regional differences in work mortality and injury rates (as dependent variables) and socio-demographic factors (occupation and population) and variables describing alcohol consumption, mean age and availability of health care (as independent variables). Data sources are from ISTAT, INAIL, Health for All database and the national report Osservasalute. The analysis was carried out using data coming from all the Italian Regions. The mean work mortality rate for the period 2006-2014 was 7.73 (DS 1.85) per 100,000 workers, while the injury rate was 4503.1 (DS 1413.5) per 100,000 workers. Socio-demographic variables and that related to health care (TC availability) were inversely associated with mortality rates, while for the work injury rates, significant associations with alcohol were found, while Gross domestic product and TC availability were inversely associated. The study pointed out the extreme heterogeneity between different geographical areas in the field of work injury, due to different socio-demographic and economic factors. In the future, health surveillance and work injury and mortality rates could be improved in areas at high risk.

  8. 3D CSEM inversion based on goal-oriented adaptive finite element method

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Key, K.

    2016-12-01

    We present a parallel 3D frequency domain controlled-source electromagnetic inversion code name MARE3DEM. Non-linear inversion of observed data is performed with the Occam variant of regularized Gauss-Newton optimization. The forward operator is based on the goal-oriented finite element method that efficiently calculates the responses and sensitivity kernels in parallel using a data decomposition scheme where independent modeling tasks contain different frequencies and subsets of the transmitters and receivers. To accommodate complex 3D conductivity variation with high flexibility and precision, we adopt the dual-grid approach where the forward mesh conforms to the inversion parameter grid and is adaptively refined until the forward solution converges to the desired accuracy. This dual-grid approach is memory efficient, since the inverse parameter grid remains independent from fine meshing generated around the transmitter and receivers by the adaptive finite element method. Besides, the unstructured inverse mesh efficiently handles multiple scale structures and allows for fine-scale model parameters within the region of interest. Our mesh generation engine keeps track of the refinement hierarchy so that the map of conductivity and sensitivity kernel between the forward and inverse mesh is retained. We employ the adjoint-reciprocity method to calculate the sensitivity kernels which establish a linear relationship between changes in the conductivity model and changes in the modeled responses. Our code uses a direcy solver for the linear systems, so the adjoint problem is efficiently computed by re-using the factorization from the primary problem. Further computational efficiency and scalability is obtained in the regularized Gauss-Newton portion of the inversion using parallel dense matrix-matrix multiplication and matrix factorization routines implemented with the ScaLAPACK library. We show the scalability, reliability and the potential of the algorithm to deal with complex geological scenarios by applying it to the inversion of synthetic marine controlled source EM data generated for a complex 3D offshore model with significant seafloor topography.

  9. Uncertainty analysis in seismic tomography

    NASA Astrophysics Data System (ADS)

    Owoc, Bartosz; Majdański, Mariusz

    2017-04-01

    Velocity field from seismic travel time tomography depends on several factors like regularization, inversion path, model parameterization etc. The result also strongly depends on an initial velocity model and precision of travel times picking. In this research we test dependence on starting model in layered tomography and compare it with effect of picking precision. Moreover, in our analysis for manual travel times picking the uncertainty distribution is asymmetric. This effect is shifting the results toward faster velocities. For calculation we are using JIVE3D travel time tomographic code. We used data from geo-engineering and industrial scale investigations, which were collected by our team from IG PAS.

  10. Analysis on the threats and spatiotemporal distribution pattern of security in World Natural Heritage Sites.

    PubMed

    Wang, Zhaoguo; Yang, Zhaoping; Du, Xishihui

    2015-01-01

    World Natural Heritage Sites (WNHS) are treasures that need human protection and invite appreciation, which makes conservation of WNHS an urgent task. This paper assesses where in the world threats are most pressing and which WNHS require emergency assistance. Using an analysis of "hot spots" and inverse distance weighting, it finds that Africa is the region where WNHS are least secure. Reports of the state of the conservation of WNHS describe the many threats that exist. Of these, management activities and institutional factors are the primary threats. The paper suggests relevant measures to improve the WNHS security.

  11. Chromosomal inversion differences correlate with range overlap in passerine birds.

    PubMed

    Hooper, Daniel M; Price, Trevor D

    2017-10-01

    Chromosomal inversions evolve frequently but the reasons for this remain unclear. We used cytological descriptions of 411 species of passerine birds to identify large pericentric inversion differences between species, based on the position of the centromere. Within 81 small clades comprising 284 of the species, we found 319 differences on the 9 largest autosomes combined, 56 on the Z chromosome, and 55 on the W chromosome. We also identified inversions present within 32 species. Using a new fossil-calibrated phylogeny, we examined the phylogenetic, demographic and genomic context in which these inversions have evolved. The number of inversion differences between closely related species is consistently predicted by whether the ranges of species overlap, even when time is controlled for as far as is possible. Fixation rates vary across the autosomes, but inversions are more likely to be fixed on the Z chromosome than the average autosome. Variable mutagenic input alone (estimated by chromosome size, map length, GC content or repeat density) cannot explain the differences between chromosomes in the number of inversions fixed. Together, these results support a model in which inversions increase because of their effects on recombination suppression in the face of hybridization. Other factors associated with hybridization may also contribute, including the possibility that inversions contain incompatibility alleles, making taxa less likely to collapse following secondary contact.

  12. Chromosomal Inversions between Human and Chimpanzee Lineages Caused by Retrotransposons

    PubMed Central

    Lee, Jungnam; Han, Kyudong; Meyer, Thomas J.; Kim, Heui-Soo; Batzer, Mark A.

    2008-01-01

    The long interspersed element-1 (LINE-1 or L1) and Alu elements are the most abundant mobile elements comprising 21% and 11% of the human genome, respectively. Since the divergence of human and chimpanzee lineages, these elements have vigorously created chromosomal rearrangements causing genomic difference between humans and chimpanzees by either increasing or decreasing the size of genome. Here, we report an exotic mechanism, retrotransposon recombination-mediated inversion (RRMI), that usually does not alter the amount of genomic material present. Through the comparison of the human and chimpanzee draft genome sequences, we identified 252 inversions whose respective inversion junctions can clearly be characterized. Our results suggest that L1 and Alu elements cause chromosomal inversions by either forming a secondary structure or providing a fragile site for double-strand breaks. The detailed analysis of the inversion breakpoints showed that L1 and Alu elements are responsible for at least 44% of the 252 inversion loci between human and chimpanzee lineages, including 49 RRMI loci. Among them, three RRMI loci inverted exonic regions in known genes, which implicates this mechanism in generating the genomic and phenotypic differences between human and chimpanzee lineages. This study is the first comprehensive analysis of mobile element bases inversion breakpoints between human and chimpanzee lineages, and highlights their role in primate genome evolution. PMID:19112500

  13. Lidar extinction measurement in the mid infrared

    NASA Astrophysics Data System (ADS)

    Mitev, Valentin; Babichenko, S.; Borelli, R.; Fiorani, L.; Grigorov, I.; Nuvoli, M.; Palucci, A.; Pistilli, M.; Puiu, Ad.; Rebane, Ott; Santoro, S.

    2014-11-01

    We present a lidar measurement of atmospheric extinction coefficient. The measurement is performed by inversion of the backscatter lidar signal at wavelengths 3'000nm and 3'500nm. The inversion of the backscatter lidar signal was performed with constant extinction-to-backscatter ration values of 104 and exponential factor 0.1.

  14. The Inverse of Banded Matrices

    DTIC Science & Technology

    2013-01-01

    indexed entries all zeros. In this paper, generalizing a method of Mallik (1999) [5], we give the LU factorization and the inverse of the matrix Br,n (if it...r ≤ i ≤ r, 1 ≤ j ≤ r, with the remaining un-indexed entries all zeros. In this paper generalizing a method of Mallik (1999) [5...matrices and applications to piecewise cubic approximation, J. Comput. Appl. Math. 8 (4) (1982) 285–288. [5] R.K. Mallik , The inverse of a lower

  15. Climatic impact on community of filamentous macroalgae in the Neva estuary (eastern Baltic Sea).

    PubMed

    Gubelit, Yulia I

    2015-02-15

    In presented study the impact of climatic factors and North Atlantic Oscillation (NAO) on macroalgal community was analysed. Also the factors influencing algal community were defined with help of Principal Component and Classification analysis. It was found that climatic impact may depend on habitat features and that on different sites biomass of macroalgae correlated with different weather factors. Wind and surf may affect biomass of macroalgae adversely on some sites and at the same time on other sites they may accumulate biomass, transferring it is from adjacent areas. High direct correlation with temperature was found on sites which were protected from surf and had no stagnant events. Seasonal biomass inversely significantly correlated with average seasonal wind speed and annual NAO-index. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Allergies and risk of head and neck cancer: an original study plus meta-analysis.

    PubMed

    Hsiao, Jenn-Ren; Ou, Chun-Yen; Lo, Hung-I; Huang, Cheng-Chih; Lee, Wei-Ting; Huang, Jehn-Shyun; Chen, Ken-Chung; Wong, Tung-Yiu; Tsai, Sen-Tien; Yen, Chia-Jui; Wu, Yuan-Hua; Hsueh, Wei-Ting; Yang, Ming-Wei; Wu, Shang-Yin; Chang, Jang-Yang; Chang, Kwang-Yu; Lin, Chen-Lin; Wang, Fang-Ting; Wang, Yi-Hui; Weng, Ya-Ling; Yang, Han-Chien; Chang, Jeffrey S

    2013-01-01

    Although the relationship between allergy and cancer has been investigated extensively, the role of allergy in head and neck cancer (HNC) appears less consistent. It is not clear whether allergies can independently influence the risk of HNC in the presence of known strong environmental risk factors, including consumption of alcohol, betel quid, and cigarette. THE CURRENT PAPER REPORTS RESULTS FROM: 1) an original hospital-based case-control study, which included 252 incident cases of HNC and 236 controls frequency-matched to cases on sex and age; and 2) a meta-analysis combining the results of the current case-control study and 13 previously published studies (9 cohort studies with 727,569 subjects and 550 HNC outcomes and 5 case-control studies with 4,017 HNC cases and 10,928 controls). In the original case-control study, we observed a strong inverse association between allergies and HNC [odds ratio = 0.41, 95% confidence interval (CI): 0.27-0.62]. The meta-analysis also indicated a statistically significant inverse association between HNC and allergies [meta-relative risk (RR) = 0.76, 95% CI: 0.63-0.91], particularly strong for allergic rhinitis (meta-RR = 0.55, 95% CI: 0.40-0.76). In addition, the inverse association between allergies and HNC was observed only among men (meta-RR = 0.67, 95% CI: 0.54-0.84) but not among women (meta-RR = 0.98, 95% CI: 0.81-1.18). These findings suggest that immunity plays an influential role in the risk of HNC. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are warranted to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help devise effective strategies to reduce and treat HNC.

  17. Does mental health staffing level affect antipsychotic prescribing? Analysis of Italian national statistics.

    PubMed

    Starace, Fabrizio; Mungai, Francesco; Barbui, Corrado

    2018-01-01

    In mental healthcare, one area of major concern identified by health information systems is variability in antipsychotic prescribing. While most studies have investigated patient- and prescriber-related factors as possible reasons for such variability, no studies have investigated facility-level characteristics. The present study ascertained whether staffing level is associated with antipsychotic prescribing in community mental healthcare. A cross-sectional analysis of data extracted from the Italian national mental health information system was carried out. For each Italian region, it collects data on the availability and use of mental health facilities. The rate of individuals exposed to antipsychotic drugs was tested for evidence of association with the rate of mental health staff availability by means of univariate and multivariate analyses. In Italy there were on average nearly 60 mental health professionals per 100,000 inhabitants, with wide regional variations (range 21 to 100). The average rate of individuals prescribed antipsychotic drugs was 2.33%, with wide regional variations (1.04% to 4.01%). Univariate analysis showed that the rate of individuals prescribed antipsychotic drugs was inversely associated with the rate of mental health professionals available in Italian regions (Kendall's tau -0.438, p = 0.006), with lower rates of antipsychotic prescriptions in regions with higher rates of mental health professionals. After adjustment for possible confounders, the total availability of mental health professionals was still inversely associated with the rate of individuals exposed to antipsychotic drugs. The evidence that staffing level was inversely associated with antipsychotic prescribing indicates that any actions aimed at decreasing variability in antipsychotic prescribing need to take into account aspects related to the organization of the mental health system.

  18. Wavelet-based multiscale adjoint waveform-difference tomography using body and surface waves

    NASA Astrophysics Data System (ADS)

    Yuan, Y. O.; Simons, F. J.; Bozdag, E.

    2014-12-01

    We present a multi-scale scheme for full elastic waveform-difference inversion. Using a wavelet transform proves to be a key factor to mitigate cycle-skipping effects. We start with coarse representations of the seismogram to correct a large-scale background model, and subsequently explain the residuals in the fine scales of the seismogram to map the heterogeneities with great complexity. We have previously applied the multi-scale approach successfully to body waves generated in a standard model from the exploration industry: a modified two-dimensional elastic Marmousi model. With this model we explored the optimal choice of wavelet family, number of vanishing moments and decomposition depth. For this presentation we explore the sensitivity of surface waves in waveform-difference tomography. The incorporation of surface waves is rife with cycle-skipping problems compared to the inversions considering body waves only. We implemented an envelope-based objective function probed via a multi-scale wavelet analysis to measure the distance between predicted and target surface-wave waveforms in a synthetic model of heterogeneous near-surface structure. Our proposed method successfully purges the local minima present in the waveform-difference misfit surface. An elastic shallow model with 100~m in depth is used to test the surface-wave inversion scheme. We also analyzed the sensitivities of surface waves and body waves in full waveform inversions, as well as the effects of incorrect density information on elastic parameter inversions. Based on those numerical experiments, we ultimately formalized a flexible scheme to consider both body and surface waves in adjoint tomography. While our early examples are constructed from exploration-style settings, our procedure will be very valuable for the study of global network data.

  19. Elevated serum bilirubin levels are inversely associated with coronary artery atherosclerosis.

    PubMed

    Kang, Seung Joo; Kim, Donghee; Park, Hyo Eun; Chung, Goh Eun; Choi, Seung Ho; Choi, Su-Yeon; Lee, Whal; Kim, Joo Sung; Cho, Sang-Heon

    2013-10-01

    Inverse correlations of high serum bilirubin with metabolic and cardiovascular disease have been suggested. However, anti-atherogenic effects of bilirubin have not been well-established in terms of the presence of plaques and stenosis identified in coronary computed tomography (CT). A cross-sectional study was conducted on 2862 men who were free of cardiovascular disease and underwent coronary CT as part of a routine medical screening examination. Coronary stenotic lesions were considered to be incidences of coronary atherosclerosis, and stenosis was classified as stenosis <50% or ≥50%, according to degree of stenosis. The prevalences of coronary atherosclerosis and stenosis ≥50% in subjects with elevated bilirubin levels (>1.2 mg/dL) were lower than those in subjects with normal bilirubin levels (≤1.2 mg/dL) (19.9% vs. 27.9%, p < 0.001, 8.5% vs. 10.3%, p = 0.044). Bilirubin was inversely associated with total plaques (odds ratio [OR] 0.59, 95% confidence interval [CI] 0.48-0.73 in the 4th quartile vs. 1st quartile) and calcified plaques (OR 0.60, 95% CI 0.49-0.75) in univariate analysis. After adjusting for traditional risk factors, it was found that coronary atherosclerosis (OR 0.73, 95% CI 0.56-0.94 in the 4th quartile vs. 1st quartile) and calcified plaque (OR 0.66, 95% CI 0.53-0.84) were inversely associated with the bilirubin grade in a dose-dependent manner. The serum bilirubin level was inversely associated with coronary atherosclerosis and calcified plaques in a dose-dependent manner. These results suggested that serum bilirubin could be used as a protective biomarker of coronary artery disease. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Development and simulation study of a new inverse-pinch high Coulomb transfer switch

    NASA Technical Reports Server (NTRS)

    Choi, Sang H.

    1989-01-01

    The inverse-pinch plasma switch was studied using a computer simulation code. The code was based on a 2-D, 2-temperature magnetohydrodynamic (MHD) model. The application of this code was limited to the disk-type inverse-pinch plasma switch. The results of the computer analysis appear to be in agreement with the experimental results when the same parameters are used. An inverse-pinch plasma switch for closing has been designed and tested for high-power switching requirements. An azimuthally uniform initiation of breakdown is a key factor in achieving an inverse-pinch current path in the switch. Thus, various types of triggers, such as trigger pins, wire-brush, ring trigger, and hypocycloidal-pinch (HCP) devices have been tested for uniform breakdown. Recently, triggering was achieved by injection of a plasma-ring (plasma puff) that is produced separately with hypocycloidal-pinch electrodes placed under the cathode of the main gap. The current paths at switch closing, initiated by the injection of a plasma-ring from the HCP trigger are azimuthally uniform, and the local current density is significantly reduced, so that damage to the electrodes and the insulator surfaces is minimized. The test results indicate that electron bombardment on the electrodes and the insulator surfaces is minimized. The test results indicate that electron bombardment on the electrodes is four orders of magnitude less than that of a spark-gap switch for the same switching power. Indeed, a few thousand shots with peak current exceeding a mega-ampere and with hold-off voltage up to 20 kV have been conducted without showing measurable damage to the electrodes and insulators.

  1. Numerical methods for the inverse problem of density functional theory

    DOE PAGES

    Jensen, Daniel S.; Wasserman, Adam

    2017-07-17

    Here, the inverse problem of Kohn–Sham density functional theory (DFT) is often solved in an effort to benchmark and design approximate exchange-correlation potentials. The forward and inverse problems of DFT rely on the same equations but the numerical methods for solving each problem are substantially different. We examine both problems in this tutorial with a special emphasis on the algorithms and error analysis needed for solving the inverse problem. Two inversion methods based on partial differential equation constrained optimization and constrained variational ideas are introduced. We compare and contrast several different inversion methods applied to one-dimensional finite and periodic modelmore » systems.« less

  2. Numerical methods for the inverse problem of density functional theory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jensen, Daniel S.; Wasserman, Adam

    Here, the inverse problem of Kohn–Sham density functional theory (DFT) is often solved in an effort to benchmark and design approximate exchange-correlation potentials. The forward and inverse problems of DFT rely on the same equations but the numerical methods for solving each problem are substantially different. We examine both problems in this tutorial with a special emphasis on the algorithms and error analysis needed for solving the inverse problem. Two inversion methods based on partial differential equation constrained optimization and constrained variational ideas are introduced. We compare and contrast several different inversion methods applied to one-dimensional finite and periodic modelmore » systems.« less

  3. System parameter identification from projection of inverse analysis

    NASA Astrophysics Data System (ADS)

    Liu, K.; Law, S. S.; Zhu, X. Q.

    2017-05-01

    The output of a system due to a change of its parameters is often approximated with the sensitivity matrix from the first order Taylor series. The system output can be measured in practice, but the perturbation in the system parameters is usually not available. Inverse sensitivity analysis can be adopted to estimate the unknown system parameter perturbation from the difference between the observation output data and corresponding analytical output data calculated from the original system model. The inverse sensitivity analysis is re-visited in this paper with improvements based on the Principal Component Analysis on the analytical data calculated from the known system model. The identification equation is projected into a subspace of principal components of the system output, and the sensitivity of the inverse analysis is improved with an iterative model updating procedure. The proposed method is numerical validated with a planar truss structure and dynamic experiments with a seven-storey planar steel frame. Results show that it is robust to measurement noise, and the location and extent of stiffness perturbation can be identified with better accuracy compared with the conventional response sensitivity-based method.

  4. Joint Stochastic Inversion of Pre-Stack 3D Seismic Data and Well Logs for High Resolution Hydrocarbon Reservoir Characterization

    NASA Astrophysics Data System (ADS)

    Torres-Verdin, C.

    2007-05-01

    This paper describes the successful implementation of a new 3D AVA stochastic inversion algorithm to quantitatively integrate pre-stack seismic amplitude data and well logs. The stochastic inversion algorithm is used to characterize flow units of a deepwater reservoir located in the central Gulf of Mexico. Conventional fluid/lithology sensitivity analysis indicates that the shale/sand interface represented by the top of the hydrocarbon-bearing turbidite deposits generates typical Class III AVA responses. On the other hand, layer- dependent Biot-Gassmann analysis shows significant sensitivity of the P-wave velocity and density to fluid substitution. Accordingly, AVA stochastic inversion, which combines the advantages of AVA analysis with those of geostatistical inversion, provided quantitative information about the lateral continuity of the turbidite reservoirs based on the interpretation of inverted acoustic properties (P-velocity, S-velocity, density), and lithotype (sand- shale) distributions. The quantitative use of rock/fluid information through AVA seismic amplitude data, coupled with the implementation of co-simulation via lithotype-dependent multidimensional joint probability distributions of acoustic/petrophysical properties, yields accurate 3D models of petrophysical properties such as porosity and permeability. Finally, by fully integrating pre-stack seismic amplitude data and well logs, the vertical resolution of inverted products is higher than that of deterministic inversions methods.

  5. Inverse Modelling Problems in Linear Algebra Undergraduate Courses

    ERIC Educational Resources Information Center

    Martinez-Luaces, Victor E.

    2013-01-01

    This paper will offer an analysis from a theoretical point of view of mathematical modelling, applications and inverse problems of both causation and specification types. Inverse modelling problems give the opportunity to establish connections between theory and practice and to show this fact, a simple linear algebra example in two different…

  6. Height, adiposity and body fat distribution and breast density in young women.

    PubMed

    Dorgan, Joanne F; Klifa, Catherine; Shepherd, John A; Egleston, Brian L; Kwiterovich, Peter O; Himes, John H; Gabriel, Kelley; Horn, Linda; Snetselaar, Linda G; Stevens, Victor J; Barton, Bruce A; Robson, Alan M; Lasser, Norman L; Deshmukh, Snehal; Hylton, Nola M

    2012-07-13

    Breast density is one of the strongest risk factors for breast cancer, but determinants of breast density in young women remain largely unknown. Associations of height, adiposity and body fat distribution with percentage dense breast volume (%DBV) and absolute dense breast volume (ADBV) were evaluated in a cross-sectional study of 174 healthy women, 25 to 29 years old. Adiposity and body fat distribution were measured by anthropometry and dual-energy X-ray absorptiometry (DXA), while %DBV and ADBV were measured by magnetic resonance imaging. Associations were evaluated using linear mixed-effects models. All tests of statistical significance are two-sided. Height was significantly positively associated with %DBV but not ADBV; for each standard deviation (SD) increase in height, %DBV increased by 18.7% in adjusted models. In contrast, all measures of adiposity and body fat distribution were significantly inversely associated with %DBV; a SD increase in body mass index (BMI), percentage fat mass, waist circumference and the android:gynoid fat mass ratio (A:G ratio) was each associated significantly with a 44.4 to 47.0% decrease in %DBV after adjustment for childhood BMI and other covariates. Although associations were weaker than for %DBV, all measures of adiposity and body fat distribution also were significantly inversely associated with ADBV before adjustment for childhood BMI. After adjustment for childhood BMI, however, only the DXA measures of percentage fat mass and A:G ratio remained significant; a SD increase in each was associated with a 13.8 to 19.6% decrease in ADBV. In mutually adjusted analysis, the percentage fat mass and the A:G ratio remained significantly inversely associated with %DBV, but only the A:G ratio was significantly associated with ADBV; a SD increase in the A:G ratio was associated with an 18.5% decrease in ADBV. Total adiposity and body fat distribution are independently inversely associated with %DBV, whereas in mutually adjusted analysis only body fat distribution (A:G ratio) remained significantly inversely associated with ADBV in young women. Research is needed to identify biological mechanisms underlying these associations.

  7. Inferring Muscle-Tendon Unit Power from Ankle Joint Power during the Push-Off Phase of Human Walking: Insights from a Multiarticular EMG-Driven Model

    PubMed Central

    2016-01-01

    Introduction Inverse dynamics joint kinetics are often used to infer contributions from underlying groups of muscle-tendon units (MTUs). However, such interpretations are confounded by multiarticular (multi-joint) musculature, which can cause inverse dynamics to over- or under-estimate net MTU power. Misestimation of MTU power could lead to incorrect scientific conclusions, or to empirical estimates that misguide musculoskeletal simulations, assistive device designs, or clinical interventions. The objective of this study was to investigate the degree to which ankle joint power overestimates net plantarflexor MTU power during the Push-off phase of walking, due to the behavior of the flexor digitorum and hallucis longus (FDHL)–multiarticular MTUs crossing the ankle and metatarsophalangeal (toe) joints. Methods We performed a gait analysis study on six healthy participants, recording ground reaction forces, kinematics, and electromyography (EMG). Empirical data were input into an EMG-driven musculoskeletal model to estimate ankle power. This model enabled us to parse contributions from mono- and multi-articular MTUs, and required only one scaling and one time delay factor for each subject and speed, which were solved for based on empirical data. Net plantarflexing MTU power was computed by the model and quantitatively compared to inverse dynamics ankle power. Results The EMG-driven model was able to reproduce inverse dynamics ankle power across a range of gait speeds (R2 ≥ 0.97), while also providing MTU-specific power estimates. We found that FDHL dynamics caused ankle power to slightly overestimate net plantarflexor MTU power, but only by ~2–7%. Conclusions During Push-off, FDHL MTU dynamics do not substantially confound the inference of net plantarflexor MTU power from inverse dynamics ankle power. However, other methodological limitations may cause inverse dynamics to overestimate net MTU power; for instance, due to rigid-body foot assumptions. Moving forward, the EMG-driven modeling approach presented could be applied to understand other tasks or larger multiarticular MTUs. PMID:27764110

  8. Inferring Muscle-Tendon Unit Power from Ankle Joint Power during the Push-Off Phase of Human Walking: Insights from a Multiarticular EMG-Driven Model.

    PubMed

    Honert, Eric C; Zelik, Karl E

    2016-01-01

    Inverse dynamics joint kinetics are often used to infer contributions from underlying groups of muscle-tendon units (MTUs). However, such interpretations are confounded by multiarticular (multi-joint) musculature, which can cause inverse dynamics to over- or under-estimate net MTU power. Misestimation of MTU power could lead to incorrect scientific conclusions, or to empirical estimates that misguide musculoskeletal simulations, assistive device designs, or clinical interventions. The objective of this study was to investigate the degree to which ankle joint power overestimates net plantarflexor MTU power during the Push-off phase of walking, due to the behavior of the flexor digitorum and hallucis longus (FDHL)-multiarticular MTUs crossing the ankle and metatarsophalangeal (toe) joints. We performed a gait analysis study on six healthy participants, recording ground reaction forces, kinematics, and electromyography (EMG). Empirical data were input into an EMG-driven musculoskeletal model to estimate ankle power. This model enabled us to parse contributions from mono- and multi-articular MTUs, and required only one scaling and one time delay factor for each subject and speed, which were solved for based on empirical data. Net plantarflexing MTU power was computed by the model and quantitatively compared to inverse dynamics ankle power. The EMG-driven model was able to reproduce inverse dynamics ankle power across a range of gait speeds (R2 ≥ 0.97), while also providing MTU-specific power estimates. We found that FDHL dynamics caused ankle power to slightly overestimate net plantarflexor MTU power, but only by ~2-7%. During Push-off, FDHL MTU dynamics do not substantially confound the inference of net plantarflexor MTU power from inverse dynamics ankle power. However, other methodological limitations may cause inverse dynamics to overestimate net MTU power; for instance, due to rigid-body foot assumptions. Moving forward, the EMG-driven modeling approach presented could be applied to understand other tasks or larger multiarticular MTUs.

  9. OCT structure, COB location and magmatic type of the SE Brazilian & S Angolan margins from integrated quantitative analysis of deep seismic reflection and gravity anomaly data

    NASA Astrophysics Data System (ADS)

    Cowie, L.; Kusznir, N. J.; Horn, B.

    2013-12-01

    Knowledge of ocean-continent transition (OCT) structure, continent-ocean boundary (COB) location and magmatic type are of critical importance for understanding rifted continental margin formation processes and in evaluating petroleum systems in deep-water frontier oil and gas exploration. The OCT structure, COB location and magmatic type of the SE Brazilian and S Angolan rifted continental margins are much debated; exhumed and serpentinised mantle have been reported at these margins. Integrated quantitative analysis using deep seismic reflection data and gravity inversion have been used to determine OCT structure, COB location and magmatic type for the SE Brazilian and S Angolan margins. Gravity inversion has been used to determine Moho depth, crustal basement thickness and continental lithosphere thinning. Residual Depth Anomaly (RDA) analysis has been used to investigate OCT bathymetric anomalies with respect to expected oceanic bathymetries and subsidence analysis has been used to determine the distribution of continental lithosphere thinning. These techniques have been validated on the Iberian margin for profiles IAM9 and ISE-01. In addition a joint inversion technique using deep seismic reflection and gravity anomaly data has been applied to the ION-GXT BS1-575 SE Brazil and ION-GXT CS1-2400 S Angola. The joint inversion method solves for coincident seismic and gravity Moho in the time domain and calculates the lateral variations in crustal basement densities and velocities along profile. Gravity inversion, RDA and subsidence analysis along the S Angolan ION-GXT CS1-2400 profile has been used to determine OCT structure and COB location. Analysis suggests that exhumed mantle, corresponding to a magma poor margin, is absent beneath the allochthonous salt. The thickness of earliest oceanic crust, derived from gravity and deep seismic reflection data is approximately 7km. The joint inversion predicts crustal basement densities and seismic velocities which are slightly less than expected for 'normal' oceanic crust. The difference between the sediment corrected RDA and that predicted from gravity inversion crustal thickness variation implies that this margin is experiencing ~300m of anomalous uplift attributed to mantle dynamic uplift. Gravity inversion, RDA and subsidence analysis have also been used to determine OCT structure and COB location along the ION-GXT BS1-575 profile, crossing the Sao Paulo Plateau and Florianopolis Ridge of the SE Brazilian margin. Gravity inversion, RDA and subsidence analysis predict the COB to be located SE of the Florianopolis Ridge. Analysis shows no evidence for exhumed mantle on this margin profile. The joint inversion technique predicts normal oceanic basement seismic velocities and densities and beneath the Sao Paulo Plateau and Florianopolis Ridge predicts crustal basement thicknesses between 10-15km. The Sao Paulo Plateau and Florianopolis Ridge are separated by a thin region of crustal basement beneath the salt interpreted as a regional transtensional structure. Sediment corrected RDAs and gravity derived 'synthetic' RDAs are of a similar magnitude on oceanic crust, implying negligible mantle dynamic topography.

  10. Factors associated with parental recognition of a child's overweight status - a cross sectional study

    PubMed Central

    2011-01-01

    Background Very few studies have evaluated the association between a child's lifestyle factors and their parent's ability to recognise the overweight status of their offspring. The aim of this study was to analyze the factors associated with a parent's ability to recognise their own offspring's overweight status. Methods 125 overweight children out of all 1,278 school beginners in Northern Finland were enrolled. Weight and height were measured in health care clinics. Overweight status was defined by BMI according to internationally accepted criteria. A questionnaire to be filled in by parents was delivered by the school nurses. The parents were asked to evaluate their offspring's weight status. The child's eating habits and physical activity patterns were also enquired about. Factor groups of food and physical activity habits were formed by factor analysis. Binary logistic regression was performed using all variables associated with recognition of overweight status in univariate analyses. The significant risk factors in the final model are reported using odds ratios (ORs) and their 95% confidence intervals (CIs). Results Fifty-seven percent (69/120) of the parents of the overweight children considered their child as normal weight. Child's BMI was positively associated with parental recognition of overweight (OR 3.59, CI 1.8 to 7.0). Overweight boys were less likely to be recognised than overweight girls (OR 0.14, CI 0.033 to 0.58). Child's healthy diet (OR 0.22, CI 0.091 to 0.54) and high physical activity (OR 0.29, CI 0.11 to 0.79) were inversely related to parental recognition of overweight status. Conclusions Child's healthy eating habits and physical activity are inversely related to parental recognition of their offspring's overweight. These should be taken into account when planning prevention and treatment strategies for childhood obesity. PMID:21864365

  11. Frequency of soup intake is inversely associated with body mass index, waist circumference, and waist-to-hip ratio, but not with other metabolic risk factors in Japanese men.

    PubMed

    Kuroda, Motonaka; Ohta, Masanori; Okufuji, Tatsuya; Takigami, Chieko; Eguchi, Masafumi; Hayabuchi, Hitomi; Ikeda, Masaharu

    2011-01-01

    Several previous studies have shown that the intake of soup negatively correlates with the body mass index (BMI), serum cholesterol and triacylglycerol levels, and blood pressure, suggesting that soup intake reduces metabolic risk. However, the correlation between soup intake and various metabolic risk factors has not been well-established. Especially, it has not been investigated in Asian countries. The aim of this study was to investigate the association of the frequency of soup intake and metabolic risk factors such as BMI, waist circumference, waist-to-hip ratio, serum cholesterol, serum triacylglycerol, blood glucose, and glycated hemoglobin. A cross-sectional study of 103 Japanese men aged 24 to 75 years was conducted. The intake of soup and other food was investigated by semi-quantitative food frequency questionnaires. The correlation between the frequency of soup intake and metabolic risk factors was analyzed by multiple regression analysis with a linear model. The median value of frequency of soup intake was 7.0 times per week. After adjusting for confounding factors such as age, energy intake, energy from alcohol intake, current smoking, and estimated energy expenditure, the frequency of soup intake was found to have a significant inverse association with BMI (P=0.040), waist circumference (P=0.024), and waist-to-hip ratio (P=0.001). However, no significant associations with other metabolic risk factors were found. Frequency of soup intake is negatively correlated with obesity-related physical parameters in Japanese men. Copyright © 2011 American Dietetic Association. Published by Elsevier Inc. All rights reserved.

  12. Clinical analysis of 48 cases of inverse psoriasis: a hospital-based study.

    PubMed

    Wang, Gang; Li, Chunying; Gao, Tianwen; Liu, Yufeng

    2005-01-01

    Inverse psoriasis, rare in clinical practice, refers to psoriasis only or mainly occurring at flexural sites, such as the axilla, antecubital fossae, popliteal fossae, and inguinal creases. It is also known as flexural psoriasis. With a total collection of psoriatic cases from September 2002 to December 2003 at Xijing hospital, we made a retrospective analysis of the disease history, clinical characteristics, and treatment of the patients affected with inverse psoriasis. The results showed that the major clinical manifestations of inverse psoriasis were sharply demarcated erythematous plaques with varying degrees of infiltration and minimal or no scales. Affected areas often involve the groin, axilla, genitals, and umbilicus. The disease responds well to the narrow band UVB therapy. Compared with common psoriasis, inverse psoriasis has similar and unique characteristics in terms of the affected areas, clinical symptoms, and responses to the treatment.

  13. Nuclear modification factor of D$^0$ mesons in PbPb collisions at $$\\sqrt{s_\\mathrm{NN}} = 5.02$$ TeV

    DOE PAGES

    Sirunyan, Albert M; et al.

    2018-07-10

    The transverse momentum (pt) spectrum of prompt D0 mesons and their antiparticles has been measured via the hadronic decay channels D0 to K- pi+ and D0-bar to K+ pi- in pp and PbPb collisions at a centre-of-mass energy of 5.02 TeV per nucleon pair with the CMS detector at the LHC. The measurement is performed in the D0 meson pt range of 2-100 GeV and in the rapidity range of abs(y)<1. The pp (PbPb) dataset used for this analysis corresponds to an integrated luminosity of 27.4 inverse picobarns (530 inverse microbarns). The measured D0 meson pt spectrum in pp collisionsmore » is well described by perturbative QCD calculations. The nuclear modification factor, comparing D0 meson yields in PbPb and pp collisions, was extracted for both minimum-bias and the 10% most central PbPb interactions. For central events, the D0 meson yield in the PbPb collisions is suppressed by a factor of 5-6 compared to the pp reference in the pt range of 6-10 GeV. For D0 mesons in the high-pt range of 60-100 GeV, a significantly smaller suppression is observed. The results are also compared to theoretical calculations.« less

  14. Serum uric acid is associated with dietary and lifestyle factors in elderly women in suburban Guangzhou in Guangdong province of south China.

    PubMed

    Xiong, Z; Zhu, C; Qian, X; Zhu, J; Wu, Z; Chen, L

    2013-01-01

    To estimate the prevalence of hyperuricemia and lifestyle risk factors for hyperuricemia in elderly women. Cross-sectional study. The suburban area of Guangzhou, Guangdong province, China. The study included 856 Chinese women aged 60 to 102 years who received their annual health examinations in the suburban area of Guangzhou, south China in 2002. Information on anthropometric measurements and lifestyle factors were obtained via a questionnaire processed by the attending physicians or nurses. Blood biochemistry was performed after subjects fasted for 8-14 h. Unconditional logistic regression analysis was used to investigate associations between hyperuricemia, meat intake quintiles, physical activity quintiles, and alcohol intake quintiles. The prevalence of hyperuricemia in the studied population was 12.01%. Alcohol, meat and seafood consumption; being overweight or obese; hypertension; and abnormal triglyceride levels were strongly associated with a higher prevalence of hyperuricemia. Physical activity was inversely related to the prevalence of hyperuricemia. The odds ratios for hyperuricemia for quintiles of physical activity were 1.00, 0.74, 0.72, 0.63, and 0.55 (P<0.01). Our data suggest that the prevalence of hyperuricemia is high in elderly women in suburban Guangzhou in Guangdong province of South China. Obesity, meat and seafood intake and alcohol consumption are associated with a higher prevalence of hyperuricemia, whereas daily physical activity is inversely related to the prevalence of hyperuricemia.

  15. Nuclear modification factor of D0 mesons in PbPb collisions at sqrt(s[NN]) = 5.02 TeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sirunyan, Albert M; et al.

    2017-08-16

    The transverse momentum (pt) spectrum of prompt D0 mesons and their antiparticles has been measured via the hadronic decay channels D0 to K- pi+ and D0-bar to K+ pi- in pp and PbPb collisions at a centre-of-mass energy of 5.02 TeV per nucleon pair with the CMS detector at the LHC. The measurement is performed in the D0 meson pt range of 2-100 GeV and in the rapidity range of abs(y)<1. The pp (PbPb) dataset used for this analysis corresponds to an integrated luminosity of 27.4 inverse picobarns (530 inverse microbarns). The measured D0 meson pt spectrum in pp collisionsmore » is well described by perturbative QCD calculations. The nuclear modification factor, comparing D0 meson yields in PbPb and pp collisions, was extracted for both minimum-bias and the 10% most central PbPb interactions. For central events, the D0 meson yield in the PbPb collisions is suppressed by a factor of 5-6 compared to the pp reference in the pt range of 6-10 GeV. For D0 mesons in the high-pt range of 60-100 GeV, a significantly smaller suppression is observed. The results are also compared to theoretical calculations.« less

  16. Reproductive factors and ovarian cancer risk in African-American women.

    PubMed

    Moorman, Patricia G; Alberg, Anthony J; Bandera, Elisa V; Barnholtz-Sloan, Jill; Bondy, Melissa; Cote, Michele L; Funkhouser, Ellen; Peters, Edward S; Schwartz, Ann G; Terry, Paul; Crankshaw, Sydnee; Wang, Frances; Schildkraut, Joellen M

    2016-09-01

    Reproductive characteristics, the most established ovarian cancer risk factors, differ markedly between African-American and white women. Studies in predominantly white populations suggest that associations between reproductive characteristics and ovarian cancer vary by timing of the events and menopause status. This analysis examined associations between number, duration, and timing of reproductive events and epithelial ovarian cancer among African-American women. Data from a multicenter case-control study of ovarian cancer in African-American women (641 cases/752 controls) were used to examine associations with oral contraceptive (OC) use and pregnancy characteristics. Odds ratios (ORs) and 95% confidence intervals (CIs) associated with reproductive characteristics were calculated with logistic regression models. OC use (OR = 0.7, 95% CI 0.5-0.9), parity (OR = 0.5, 95% CI 0.3-0.6), and breastfeeding for >12 months (OR = 0.3, 95% CI 0.2-0.5) were inversely associated with ovarian cancer. More recent pregnancies and OC use had stronger associations with ovarian cancer than pregnancies or OC use that occurred earlier in life, especially among premenopausal women. This study provides the first thorough documentation that pregnancy, breastfeeding, and OC use are inversely associated with ovarian cancer in African-American women, similar to what has been observed in white women. The associations with timing of the exposures suggest that these factors have both short- and long-term effects. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Pathways from parental knowledge and warmth to adolescent marijuana use: an extension to the theory of planned behavior.

    PubMed

    Lac, Andrew; Alvaro, Eusebio M; Crano, William D; Siegel, Jason T

    2009-03-01

    Despite research indicating that effective parenting plays an important protective role in adolescent risk behaviors, few studies have applied theory to examine this link with marijuana use, especially with national data. In the current study (N = 2,141), we hypothesized that parental knowledge (of adolescent activities and whereabouts) and parental warmth are antecedents of adolescents' marijuana beliefs-attitudes, subjective norms, and perceived behavioral control-as posited by the Theory of Planned Behavior (TPB; Ajzen 1991). These three types of beliefs were hypothesized to predict marijuana intention, which in turn was hypothesized to predict marijuana consumption. Results of confirmatory factor analyses corroborated the psychometric properties of the two-factor parenting structure as well as the five-factor structure of the TPB. Further, the proposed integrative predictive framework, estimated with a latent structural equation model, was largely supported. Parental knowledge inversely predicted pro-marijuana attitudes, subjective norms, and perceived behavioral control; parental warmth inversely predicted pro-marijuana attitudes and subjective norms, ps < .001. Marijuana intention (p < .001), but not perceived behavioral control, predicted marijuana use 1 year later. In households with high parental knowledge, parental warmth also was perceived to be high (r = .54, p < .001). Owing to the analysis of nationally representative data, results are generalizable to the United States population of adolescents 12-18 years of age.

  18. Protective determinants of sickness absence among employees with multisite pain-a 7-year follow-up.

    PubMed

    Haukka, Eija; Ojajärvi, Anneli; Kaila-Kangas, Leena; Leino-Arjas, Päivi

    2017-02-01

    We identified factors protective of all-cause sickness absence (SA) among subjects with multisite musculoskeletal pain (MSP). The nationally representative source sample comprised 3420 actively working Finns aged 30 to 55 in year 2000 and alive at follow-up. Pain in 18 body locations was combined into four sites (neck, low back, upper limbs, and lower limbs). The baseline prevalence of MSP (pain in ≥ 2 sites) was 32%. Baseline data on sociodemographic factors, work ability, work, health, and lifestyle were gathered by questionnaire, interview, and clinical examination and linked with national registers on all-cause SA (periods lasting ≥10 workdays) for 2002 to 2008. Based on trajectory analysis, 74% of those with MSP had a low and 26% a high probability of SA. In logistic regression analysis, younger age, male sex, and professional occupational group were inversely associated with SA. Allowing for these, good physician-assessed work ability, physically light work, possibility to adjust workday length, encouraging workplace atmosphere, no problems with working community or mental stress, normal weight, and no sleep disorders were predictive of lower SA rates (odds ratios between 0.47 and 0.70). In a final stepwise model adjusted for age, sex, and occupational group, no exposure to lifting (odds ratio 0.58, 95% confidence interval 0.39-0.85) and to repetitive hand movements (0.57, 0.39-0.83), possibility to adjust workday length (0.73, 0.53-0.99), and normal weight (0.59, 0.40-0.87) were inversely associated with SA. In conclusion, several modifiable factors related to work and lifestyle were found as predictive of lower rates of longer SA among occupationally active subjects with MSP.

  19. Analysis of a Multi-Machine Database on Divertor Heat Fluxes

    NASA Astrophysics Data System (ADS)

    Makowski, M. A.

    2011-10-01

    A coordinated effort to measure divertor heat flux characteristics in fully attached, similarly shaped H-mode plasmas on C-Mod, DIII-D and NSTX was carried out in 2010 in order to construct a predictive scaling relation applicable to next step devices including ITER, FNSF, and DEMO. Few published scaling laws are available and those that have been published were obtained under widely varying conditions and divertor geometries, leading to conflicting predictions for this critically important quantity. This study was designed to overcome these deficiencies. Corresponding plasma parameters were systematically varied in each tokamak, resulting in a combined data set in which Ip varies by a factor 3, Bt varies by a factor of 14.5, and major radius varies by a factor of 2.6. The derived scaling relation consistently predicts narrower heat flux widths than relations currently in use. Analysis of the combined data set reveals that the primary dependence of the parallel heat flux width is robustly inverse with Ip. All three tokamaks independently demonstrate this dependence. The midplane SOL profiles in DIII-D are also found to steepen with higher Ip, similar to the divertor heat flux profiles. Weaker dependencies on the toroidal field and normalized Greenwald density, fGW, are also found, but vary across devices and with the measure of the heat flux width used, either FWHM or integral width. In the combined data set, the strongest size scaling is with minor radius resulting in an approximately linear dependence on a /Ip . This suggests a scaling correlated with the inverse of the poloidal field, as would be expected for critical gradient or drift-based transport. Supported by the US DOE under DE-AC52-07NA27344 and DE-FC02-04ER54698.

  20. An ambiguity of information content and error in an ill-posed satellite inversion

    NASA Astrophysics Data System (ADS)

    Koner, Prabhat

    According to Rodgers (2000, stochastic approach), the averaging kernel (AK) is the representational matrix to understand the information content in a scholastic inversion. On the other hand, in deterministic approach this is referred to as model resolution matrix (MRM, Menke 1989). The analysis of AK/MRM can only give some understanding of how much regularization is imposed on the inverse problem. The trace of the AK/MRM matrix, which is the so-called degree of freedom from signal (DFS; stochastic) or degree of freedom in retrieval (DFR; deterministic). There are no physical/mathematical explanations in the literature: why the trace of the matrix is a valid form to calculate this quantity? We will present an ambiguity between information and error using a real life problem of SST retrieval from GOES13. The stochastic information content calculation is based on the linear assumption. The validity of such mathematics in satellite inversion will be questioned because it is based on the nonlinear radiative transfer and ill-conditioned inverse problems. References: Menke, W., 1989: Geophysical data analysis: discrete inverse theory. San Diego academic press. Rodgers, C.D., 2000: Inverse methods for atmospheric soundings: theory and practice. Singapore :World Scientific.

  1. FDG-PET/CT and diffusion-weighted imaging for resected lung cancer: correlation of maximum standardized uptake value and apparent diffusion coefficient value with prognostic factors.

    PubMed

    Usuda, Katsuo; Funasaki, Aika; Sekimura, Atsushi; Motono, Nozomu; Matoba, Munetaka; Doai, Mariko; Yamada, Sohsuke; Ueda, Yoshimichi; Uramoto, Hidetaka

    2018-04-09

    Diffusion-weighted magnetic resonance imaging (DWI) is useful for detecting malignant tumors and the assessment of lymph nodes, as FDG-PET/CT is. But it is not clear how DWI influences the prognosis of lung cancer patients. The focus of this study is to evaluate the correlations between maximum standardized uptake value (SUVmax) of FDG-PET/CT and apparent diffusion coefficient (ADC) value of DWI with known prognostic factors in resected lung cancer. A total of 227 patients with resected lung cancers were enrolled in this study. FEG-PET/CT and DWI were performed in each patient before surgery. There were 168 patients with adenocarcinoma, 44 patients with squamous cell carcinoma, and 15 patients with other cell types. SUVmax was a factor that was correlated to T factor, N factor, or cell differentiation. ADC of lung cancer was a factor that was not correlated to T factor, or N factor. There was a significantly weak inverse relationship between SUVmax and ADC (Correlation coefficient r = - 0.227). In analysis of survival, there were significant differences between the categories of sex, age, pT factor, pN factor, cell differentiation, cell type, and SUVmax. Univariate analysis revealed that SUVmax, pN factor, age, cell differentiation, cell type, sex, and pT factor were significant factors. Multivariate analysis revealed that SUVmax and pN factor were independent significant prognostic factors. SUVmax was a significant prognostic factor that is correlated to T factor, N factor, or cell differentiation, but ADC was not. SUVmax may be more useful for predicting the prognosis of lung cancer than ADC values.

  2. High-resolution inversion of methane emissions in the Southeast US using SEAC4RS aircraft observations of atmospheric methane: anthropogenic and wetland sources

    NASA Astrophysics Data System (ADS)

    Sheng, Jian-Xiong; Jacob, Daniel J.; Turner, Alexander J.; Maasakkers, Joannes D.; Sulprizio, Melissa P.; Bloom, A. Anthony; Andrews, Arlyn E.; Wunch, Debra

    2018-05-01

    We use observations of boundary layer methane from the SEAC4RS aircraft campaign over the Southeast US in August-September 2013 to estimate methane emissions in that region through an inverse analysis with up to 0.25° × 0.3125° (25×25 km2) resolution and with full error characterization. The Southeast US is a major source region for methane including large contributions from oil and gas production and wetlands. Our inversion uses state-of-the-art emission inventories as prior estimates, including a gridded version of the anthropogenic EPA Greenhouse Gas Inventory and the mean of the WetCHARTs ensemble for wetlands. Inversion results are independently verified by comparison with surface (NOAA/ESRL) and column (TCCON) methane observations. Our posterior estimates for the Southeast US are 12.8 ± 0.9 Tg a-1 for anthropogenic sources (no significant change from the gridded EPA inventory) and 9.4 ± 0.8 Tg a-1 for wetlands (27 % decrease from the mean in the WetCHARTs ensemble). The largest source of error in the WetCHARTs wetlands ensemble is the land cover map specification of wetland areal extent. Our results support the accuracy of the EPA anthropogenic inventory on a regional scale but there are significant local discrepancies for oil and gas production fields, suggesting that emission factors are more variable than assumed in the EPA inventory.

  3. Earth's core and inner-core resonances from analysis of VLBI nutation and superconducting gravimeter data

    NASA Astrophysics Data System (ADS)

    Rosat, S.; Lambert, S. B.; Gattano, C.; Calvo, M.

    2017-01-01

    Geophysical parameters of the deep Earth's interior can be evaluated through the resonance effects associated with the core and inner-core wobbles on the forced nutations of the Earth's figure axis, as observed by very long baseline interferometry (VLBI), or on the diurnal tidal waves, retrieved from the time-varying surface gravity recorded by superconducting gravimeters (SGs). In this paper, we inverse for the rotational mode parameters from both techniques to retrieve geophysical parameters of the deep Earth. We analyse surface gravity data from 15 SG stations and VLBI delays accumulated over the last 35 yr. We show existing correlations between several basic Earth parameters and then decide to inverse for the rotational modes parameters. We employ a Bayesian inversion based on the Metropolis-Hastings algorithm with a Markov-chain Monte Carlo method. We obtain estimates of the free core nutation resonant period and quality factor that are consistent for both techniques. We also attempt an inversion for the free inner-core nutation (FICN) resonant period from gravity data. The most probable solution gives a period close to the annual prograde term (or S1 tide). However the 95 per cent confidence interval extends the possible values between roughly 28 and 725 d for gravity, and from 362 to 414 d from nutation data, depending on the prior bounds. The precisions of the estimated long-period nutation and respective small diurnal tidal constituents are hence not accurate enough for a correct determination of the FICN complex frequency.

  4. Difference in adherence to and influencing factors of a healthy lifestyle between middle-aged and elderly people in Korea: A multilevel analysis.

    PubMed

    Son, Ki Young; Park, Sang Min; Lee, Juhyun; Kim, Chang Yup

    2015-06-01

    Comprehensive research for factors related to healthy lifestyles of the elderly is limited. The present study aimed to elucidate the factors associated with adherence to a healthy lifestyle by age groups. The present study was based on data from the 2005 Korea National Health and Nutrition Examination Survey. We calculated crude proportions and adjusted proportions of cigarette smokers, problem alcohol drinkers, and physically inactive people in two age groups (40-59 years and ≥60 years). We carried out multilevel analysis to elucidate factors associated with healthy lifestyles. Of 3194 respondents included in the analysis, 1154 (36.13%) were aged 60 years or older. Older participants smoked less (23.0% vs 17.4%) and exercised less frequently (52.4% vs 66.9%; all P < 0.001) than their middle-aged counterparts. After adjustment, the proportion of regular exercisers was inversed (adjusted proportion 0.468, 95% CI 0.436-0.501 vs 0.377, 95% CI 0.337-0.419, P = 0.004). In multilevel analysis, contextual factors, such as local tax per capita, was associated significantly with cigarette smoking only in the elderly (OR 1.037, 95% CI 1.005-1.070). Different factors were associated with healthy lifestyles of elderly people when compared with middle-aged people. In addition, local tax per capita, an area level variable, was more likely to be associated with smoking in the elderly than the middle-aged group. © 2014 Japan Geriatrics Society.

  5. Dynamic identification of growth and survival kinetic parameters of microorganisms in foods

    USDA-ARS?s Scientific Manuscript database

    Inverse analysis is a mathematical method used in predictive microbiology to determine the kinetic parameters of microbial growth and survival in foods. The traditional approach in inverse analysis relies on isothermal experiments that are time-consuming and labor-intensive, and errors are accumula...

  6. Semiautomatic and Automatic Cooperative Inversion of Seismic and Magnetotelluric Data

    NASA Astrophysics Data System (ADS)

    Le, Cuong V. A.; Harris, Brett D.; Pethick, Andrew M.; Takam Takougang, Eric M.; Howe, Brendan

    2016-09-01

    Natural source electromagnetic methods have the potential to recover rock property distributions from the surface to great depths. Unfortunately, results in complex 3D geo-electrical settings can be disappointing, especially where significant near-surface conductivity variations exist. In such settings, unconstrained inversion of magnetotelluric data is inexorably non-unique. We believe that: (1) correctly introduced information from seismic reflection can substantially improve MT inversion, (2) a cooperative inversion approach can be automated, and (3) massively parallel computing can make such a process viable. Nine inversion strategies including baseline unconstrained inversion and new automated/semiautomated cooperative inversion approaches are applied to industry-scale co-located 3D seismic and magnetotelluric data sets. These data sets were acquired in one of the Carlin gold deposit districts in north-central Nevada, USA. In our approach, seismic information feeds directly into the creation of sets of prior conductivity model and covariance coefficient distributions. We demonstrate how statistical analysis of the distribution of selected seismic attributes can be used to automatically extract subvolumes that form the framework for prior model 3D conductivity distribution. Our cooperative inversion strategies result in detailed subsurface conductivity distributions that are consistent with seismic, electrical logs and geochemical analysis of cores. Such 3D conductivity distributions would be expected to provide clues to 3D velocity structures that could feed back into full seismic inversion for an iterative practical and truly cooperative inversion process. We anticipate that, with the aid of parallel computing, cooperative inversion of seismic and magnetotelluric data can be fully automated, and we hold confidence that significant and practical advances in this direction have been accomplished.

  7. Titan's Gravitational Field

    NASA Astrophysics Data System (ADS)

    Schubert, G.; Anderson, J. D.

    2013-12-01

    Titan's gravitational field is inferred from an analysis of archived radio Doppler data for six Cassini flybys. The analysis considers each flyby separately in contrast to the approach of lumping all the data together in a massive inversion. In this way it is possible to gain an improved understanding of the character of each flyby and its usefulness in constraining the gravitational coefficient C22 . Though our analysis is not yet complete and our final determination of C22 could differ from the result we report here by 1 or 2 sigma, we find a best-fit value of C22 equal to (13.21 × 0.17) × 10-6, significantly larger than the value of 10.0 × 10-6 obtained from an inversion of the lumped Cassini data. We also find no determination of the tidal Love number k2. The larger value of C22 implies a moment of inertia factor equal to 0.3819 × 0.0020 and a less differentiated Titan than is suggested by the smaller value. The larger value of C22 is consistent with an undifferentiated model of the satellite. While it is not possible to rule out either value of C22 , we prefer the larger value because its derivation results from a more hands on analysis of the data that extracts the weak hydrostatic signal while revealing the effects of gravity anomalies and unmodeled spacecraft accelerations on each of the six flybys.

  8. The inverse problem of sensing the mass and force induced by an adsorbate on a beam nanomechanical resonator

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Yun; Zhang, Yin

    2016-06-08

    The mass sensing superiority of a micro/nanomechanical resonator sensor over conventional mass spectrometry has been, or at least, is being firmly established. Because the sensing mechanism of a mechanical resonator sensor is the shifts of resonant frequencies, how to link the shifts of resonant frequencies with the material properties of an analyte formulates an inverse problem. Besides the analyte/adsorbate mass, many other factors such as position and axial force can also cause the shifts of resonant frequencies. The in-situ measurement of the adsorbate position and axial force is extremely difficult if not impossible, especially when an adsorbate is as smallmore » as a molecule or an atom. Extra instruments are also required. In this study, an inverse problem of using three resonant frequencies to determine the mass, position and axial force is formulated and solved. The accuracy of the inverse problem solving method is demonstrated and how the method can be used in the real application of a nanomechanical resonator is also discussed. Solving the inverse problem is helpful to the development and application of mechanical resonator sensor on two things: reducing extra experimental equipments and achieving better mass sensing by considering more factors.« less

  9. Imaging of 2-D multichannel land seismic data using an iterative inversion-migration scheme, Naga Thrust and Fold Belt, Assam, India

    NASA Astrophysics Data System (ADS)

    Jaiswal, Priyank; Dasgupta, Rahul

    2010-05-01

    We demonstrate that imaging of 2-D multichannel land seismic data can be effectively accomplished by a combination of reflection traveltime tomography and pre-stack depth migration (PSDM); we refer to the combined process as "the unified imaging". The unified imaging comprises cyclic runs of joint reflection and direct arrival inversion and pre-stack depth migration. From one cycle to another, both the inversion and the migration provide mutual feedbacks that are guided by the geological interpretation. The unified imaging is implemented in two broad stages. The first stage is similar to the conventional imaging except that it involves a significant use of velocity model from the inversion of the direct arrivals for both datuming and stacking velocity analysis. The first stage ends with an initial interval velocity model (from the stacking velocity analysis) and a corresponding depth migrated image. The second stage updates the velocity model and the depth image from the first stage in a cyclic manner; a single cycle comprises a single run of reflection traveltime inversion followed by PSDM. Interfaces used in the inversion are interpretations of the PSDM image in the previous cycle and the velocity model used in PSDM is from the joint inversion in the current cycle. Additionally in every cycle interpreted horizons in the stacked data are inverted as zero-offset reflections for constraining the interfaces; the velocity model is maintained stationary for the zero-offset inversion. A congruency factor, j, which measures the discrepancy between interfaces from the interpretation of the PSDM image and their corresponding counterparts from the inversion of the zero-offset reflections within assigned uncertainties, is computed in every cycle. A value of unity for jindicates that images from both the inversion and the migration are equivalent; at this point the unified imaging is said to have converged and is halted. We apply the unified imaging to 2-D multichannel seismic data from the Naga Thrust and Fold Belt (NTFB), India, were several exploratory wells in the last decade targeting sub-thrust leads in the footwall have failed. This failure is speculatively due to incorrect depth images which are in turn attributed to incorrect velocity models that are developed using conventional methods. The 2-D seismic data in this study is acquired perpendicular to the trend of the NTFB where the outcropping hanging wall has a topographic culmination. The acquisition style is split-spread with 30 m shot and receiver spacing and a nominal fold of 90. The data are recorded with a sample interval of 2 ms. Overall the data have a moderate signal-to-noise ratio and a broad frequency bandwidth of 8-80 Hz. The seismic line contains the failed exploratory well in the central part. The final results from unified imaging (both the depth image and the corresponding velocity model) suggest presence of a triangle zone, which was previously undiscovered. Conventional imaging had falsely portrayed the triangle zone as structural high which was interpreted as an anticline. As a result, the exploratory well, meant to target the anticline, met with pressure changes which were neither expected nor explained. The unified imaging results not only explain the observations in the well but also reveal new leads in the region. The velocity model from unified imaging was also found to be adequate for frequency-domain full-waveform imaging of the hanging wall. Results from waveform inversion are further corroborated by the geological interpretation of the exploratory well.

  10. Predictions of biochar production and torrefaction performance from sugarcane bagasse using interpolation and regression analysis.

    PubMed

    Chen, Wei-Hsin; Hsu, Hung-Jen; Kumar, Gopalakrishnan; Budzianowski, Wojciech M; Ong, Hwai Chyuan

    2017-12-01

    This study focuses on the biochar formation and torrefaction performance of sugarcane bagasse, and they are predicted using the bilinear interpolation (BLI), inverse distance weighting (IDW) interpolation, and regression analysis. It is found that the biomass torrefied at 275°C for 60min or at 300°C for 30min or longer is appropriate to produce biochar as alternative fuel to coal with low carbon footprint, but the energy yield from the torrefaction at 300°C is too low. From the biochar yield, enhancement factor of HHV, and energy yield, the results suggest that the three methods are all feasible for predicting the performance, especially for the enhancement factor. The power parameter of unity in the IDW method provides the best predictions and the error is below 5%. The second order in regression analysis gives a more reasonable approach than the first order, and is recommended for the predictions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Are cardiovascular risk factors also associated with the incidence of atrial fibrillation? A systematic review and field synopsis of 23 factors in 32 population-based cohorts of 20 million participants.

    PubMed

    Allan, Victoria; Honarbakhsh, Shohreh; Casas, Juan-Pablo; Wallace, Joshua; Hunter, Ross; Schilling, Richard; Perel, Pablo; Morley, Katherine; Banerjee, Amitava; Hemingway, Harry

    2017-05-03

    Established primary prevention strategies of cardiovascular diseases are based on understanding of risk factors, but whether the same risk factors are associated with atrial fibrillation (AF) remains unclear. We conducted a systematic review and field synopsis of the associations of 23 cardiovascular risk factors and incident AF, which included 84 reports based on 28 consented and four electronic health record cohorts of 20,420,175 participants and 576,602 AF events. We identified 3-19 reports per risk factor and heterogeneity in AF definition, quality of reporting, and adjustment. We extracted relative risks (RR) and 95 % confidence intervals [CI] and visualised the number of reports with inverse (RR [CI]<1.00), or direct (RR [CI]>1.00) associations. For hypertension (13/17 reports) and obesity (19/19 reports), there were direct associations with incident AF, as there are for coronary heart disease (CHD). There were inverse associations for non-White ethnicity (5/5 reports, with RR from 0.35 to 0.84 [0.82-0.85]), total cholesterol (4/13 reports from 0.76 [0.59-0.98] to 0.94 [0.90-0.97]; 8/13 reports with non-significant inverse associations), and diastolic blood pressure (2/11 reports from 0.87 [0.78-0.96] to 0.92 [0.85-0.99]; 5/11 reports with non-significant inverse associations), and direct associations for taller height (7/10 reports from 1.03 [1.02-1.05] to 1.92 [1.38-2.67]), which are in the opposite direction of known associations with CHD. A systematic evaluation of the available evidence suggests similarities as well as important differences in the risk factors for incidence of AF as compared with other cardiovascular diseases, which has implications for the primary prevention strategies for atrial fibrillation.

  12. Polarimetric SAR Interferometry Evaluation in Mangroves

    NASA Technical Reports Server (NTRS)

    Lee, Seung-Kuk; Fatoyinbo,Temilola; Osmanoglu, Batuhan; Sun, Guoqing

    2014-01-01

    TanDEM-X (TDX) enables to generate an interferometric coherence without temporal decorrelation effect that is the most critical factor for a successful Pol-InSAR inversion, as have recently been used for forest parameter retrieval. This paper presents mangrove forest height estimation only using single-pass/single-baseline/dual-polarization TDX data by means of new dual-Pol-InSAR inversion technique. To overcome a lack of one polarization in a conventional Pol- InSAR inversion (i.e. an underdetermined problem), the ground phase in the Pol-InSAR model is directly estimated from TDX interferograms assuming flat underlying topography in mangrove forest. The inversion result is validated against lidar measurement data (NASA's G-LiHT data).

  13. Variational approach to direct and inverse problems of atmospheric pollution studies

    NASA Astrophysics Data System (ADS)

    Penenko, Vladimir; Tsvetova, Elena; Penenko, Alexey

    2016-04-01

    We present the development of a variational approach for solving interrelated problems of atmospheric hydrodynamics and chemistry concerning air pollution transport and transformations. The proposed approach allows us to carry out complex studies of different-scale physical and chemical processes using the methods of direct and inverse modeling [1-3]. We formulate the problems of risk/vulnerability and uncertainty assessment, sensitivity studies, variational data assimilation procedures [4], etc. A computational technology of constructing consistent mathematical models and methods of their numerical implementation is based on the variational principle in the weak constraint formulation specifically designed to account for uncertainties in models and observations. Algorithms for direct and inverse modeling are designed with the use of global and local adjoint problems. Implementing the idea of adjoint integrating factors provides unconditionally monotone and stable discrete-analytic approximations for convection-diffusion-reaction problems [5,6]. The general framework is applied to the direct and inverse problems for the models of transport and transformation of pollutants in Siberian and Arctic regions. The work has been partially supported by the RFBR grant 14-01-00125 and RAS Presidium Program I.33P. References: 1. V. Penenko, A.Baklanov, E. Tsvetova and A. Mahura . Direct and inverse problems in a variational concept of environmental modeling //Pure and Applied Geoph.(2012) v.169: 447-465. 2. V. V. Penenko, E. A. Tsvetova, and A. V. Penenko Development of variational approach for direct and inverse problems of atmospheric hydrodynamics and chemistry, Izvestiya, Atmospheric and Oceanic Physics, 2015, Vol. 51, No. 3, p. 311-319, DOI: 10.1134/S0001433815030093. 3. V.V. Penenko, E.A. Tsvetova, A.V. Penenko. Methods based on the joint use of models and observational data in the framework of variational approach to forecasting weather and atmospheric composition quality// Russian meteorology and hydrology, V. 40, Issue: 6, Pages: 365-373, DOI: 10.3103/S1068373915060023. 4. A.V. Penenko and V.V. Penenko. Direct data assimilation method for convection-diffusion models based on splitting scheme. Computational technologies, 19(4):69-83, 2014. 5. V.V. Penenko, E.A. Tsvetova, A.V. Penenko Variational approach and Euler's integrating factors for environmental studies// Computers and Mathematics with Applications, 2014, V.67, Issue 12, Pages 2240-2256, DOI:10.1016/j.camwa.2014.04.004 6. V.V. Penenko, E.A. Tsvetova. Variational methods of constructing monotone approximations for atmospheric chemistry models // Numerical analysis and applications, 2013, V. 6, Issue 3, pp 210-220, DOI 10.1134/S199542391303004X

  14. High-frequency envelope inversion analysis of the 2003 Tokachi-Oki, JAPAN, earthquake (Mw8.0)

    NASA Astrophysics Data System (ADS)

    Nakahara, H.

    2004-12-01

    The 2003 Tokachi-Oki earthquake (Mw 8.0) took place on September 26, 2003 at the plate interface between the subducting Pacific plate and the Hokkaido island, northern Japan. The focal depth is around 30km and the focal mechanism is thrust type. This earthquake caused 2 missings, more than 100 injures, 2000 collapsed houses, and so on. Slip distribution on the fault plane was already estimated by inversion analyses of low-frequency seismograms. However, source characteristics for the earthquake in frequencies higher than 1 Hz is not so far clarified. In this study, we execute an envelope inversion analysis based on the method by Nakahara et al. (1998) and clarify the spatial distribution of high-frequency seismic energy radiation on the fault plane of this earthquake. We use three-component sum of mean squared velocity seismograms multiplied by a density of earth medium, which is called envelopes here, for the envelope inversion analysis. Three frequency bands of 1-2, 2-4, and 4-8 Hz are adopted. We use envelopes in the time window from the onset of S waves to the lapse time of 128 sec. Green functions of envelopes representing the energy propagation process through a scattering medium are calculated based on the radiative transfer theory, which are characterized by parameters of scattering attenuation and intrinsic absorption. We use the values obtained for eastern Hokkaido (Hoshiba, 1993). We assume the fault plane as follows: strike=249o, dip=15o, rake=130o, length=150km, width=165km with reference to a waveform inversion analysis in low frequencies (e.g. Yagi, 2003). We divide this fault plane into 110 subfaults, each of which is a 15km x 15km square. Rupture velocity is assumed to be constant. Seismic energy is radiated from a point source as soon as the rupture front passes the center of each subfault. Time function of energy radiation is assumed as a box-car function. The amount of seismic energy from all the subfaults and site amplification factors for all the stations are estimated by the envelope inversion method. Rupture velocity and the duration time of a box-car function should be estimated by a grid search. Theoretical envelopes calculated with best-fit parameters generally fit to observed ones. The rupture velocity and duration time were estimated as 3.0 km/s and 6 sec, respectively. The high-frequency seismic energy was found to be radiated mainly from two spots on the fault plane: The first one is the deeper part beneath the initial rupture point and the second is the southern shallow part of the fault plane. Radiated energy was estimated to be 7.2 × 1016J in the 1-8Hz band. Acknowledgements: We used strong-motion seismograms recorded by the K-NET and KiK-net of NIED, JAPAN.

  15. Inversion exercises inspired by mechanics

    NASA Astrophysics Data System (ADS)

    Groetsch, C. W.

    2016-02-01

    An elementary calculus transform, inspired by the centroid and gyration radius, is introduced as a prelude to the study of more advanced transforms. Analysis of the transform, including its inversion, makes use of several key concepts from basic calculus and exercises in the application and inversion of the transform provide practice in the use of technology in calculus.

  16. Self-silencing and age as risk factors for sexually acquired HIV in midlife and older women.

    PubMed

    Jacobs, Robin J; Thomlison, Barbara

    2009-02-01

    Objectives. This study explores the contribution of psychosocial factors on sex behaviors of midlife and older women. Methods. A community-based sample of ethnically diverse women (N = 572) between the ages of 50 and 93 completed standardized measures of self-silencing, self-esteem, sensation seeking behavior, HIV-related stigma behavior, sexual assertiveness, and safer sex behaviors. Results. Results from the regression analysis indicated the model significantly predicted safer sex behaviors (p < .001), with self silencing(â = -.115, p < .05) and age (â = .173, p < .001) as significant predictors.Bivariate correlation analysis indicated an inverse correlation between HIV stigma (p < .05) and safer sex behaviors. Discussion. Implications for further study and practice are discussed to include considerations for development of age- and gender-appropriate prevention interventions assisting women with interpersonal processes combined with skills for active involvement in addressing high-risk sex behaviors.

  17. Use of a brief version of the self-compassion inventory with an international sample of people with HIV/AIDS

    PubMed Central

    Brion, John M.; Leary, Mark; Wantland, Dean; Sullivan, K.; Nokes, Kathleen; Bain, Catherine A; Chaiphibalsarisdi, Puangtip; Chen, Wei-ti; Holzemer, William L.; Eller, Lucille Sanzero; Iipinge, Scholastika; Johnson, Mallory O.; Portillo, Carmen; Voss, Joachim; Tyer-Viola, Lynda; Corless, Inge B; Nicholas, Patrice K; Rose, Carol Dawson; Phillips, J. Craig; Sefcik, Elizabeth; Mendez, Marta Rivero; Kirksey, Kenn M.

    2013-01-01

    The objective of this study was to extend the psychometric evaluation of a brief version of the Self Compassion Scale (SCS). A secondary analysis of data from an international sample of 1,967 English-speaking persons living with HIV disease was used to examine the factor structure, and reliability of the 12-item Brief Version Self Compassion Inventory (BVSCI). A Maximum Likelihood factor analysis and Oblimin with Kaiser Normalization confirmed a two-factor solution, accounting for 42.58% of the variance. The BVSCI supported acceptable internal consistencies, with .714 for the total scale and .822 for Factor I and .774 for Factor II. Factor I (lower self compassion) demonstrated strongly positive correlations with measures of anxiety and depression while Factor II (high self compassion) was inversely correlated with the measures. No significant differences were found in the BVSCI scores for gender, age, or having children. Levels of self-compassion were significantly higher in persons with HIV disease and other physical and psychological health conditions. The scale shows promise for the assessment of self-compassion in persons with HIV without taxing participants, and may prove essential in investigating future research aimed at examining correlates of self-compassion, as well as providing data for tailoring self-compassion interventions for persons with HIV. PMID:23527887

  18. The influence of place on weight gain during early childhood: a population-based, longitudinal study.

    PubMed

    Carter, Megan Ann; Dubois, Lise; Tremblay, Mark S; Taljaard, Monica

    2013-04-01

    The objective of this paper was to determine the influence of place factors on weight gain in a contemporary cohort of children while also adjusting for early life and individual/family social factors. Participants from the Québec Longitudinal Study of Child Development comprised the sample for analysis (n = 1,580). A mixed-effects regression analysis was conducted to determine the longitudinal relationship between these place factors and standardized BMI, from age 4 to 10 years. The average relationship with time was found to be quadratic (rate of weight gain increased over time). Neighborhood material deprivation was found to be positively related to weight gain. Social deprivation, social disorder, and living in a medium density area were inversely related, while no association was found for social cohesion. Early life factors and genetic proxies appeared to be important in explaining weight gain in this sample. This study suggests that residential environments may play a role in childhood weight change; however, pathways are likely to be complex and interacting and perhaps not as important as early life factors and genetic proxies. Further work is required to clarify these relationships.

  19. Joule-Thomson inversion curves and related coefficients for several simple fluids

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.; Peller, I. C.; Baron, A. K.

    1972-01-01

    The equations of state (PVT relations) for methane, oxygen, argon, carbon dioxide, carbon monoxide, neon, hydrogen, and helium were used to establish Joule-Thomson inversion curves for each fluid. The principle of corresponding states was applied to the inversion curves, and a generalized inversion curve for fluids with small acentric factors was developed. The quantum fluids (neon, hydrogen, and helium) were excluded from the generalization, but available data for the fluids xenon and krypton were included. The critical isenthalpic Joule-Thomson coefficient mu sub c was determined; and a simplified approximation mu sub c approximates T sub c divided by 6P sub c was found adequate, where T sub c and P sub c are the temperature and pressure at the thermodynamic critical point. The maximum inversion temperatures were obtained from the second virial coefficient (maximum (B/T)).

  20. COMPUTATIONAL ANALYSIS OF SWALLOWING MECHANICS UNDERLYING IMPAIRED EPIGLOTTIC INVERSION

    PubMed Central

    Pearson, William G.; Taylor, Brandon K; Blair, Julie; Martin-Harris, Bonnie

    2015-01-01

    Objective Determine swallowing mechanics associated with the first and second epiglottic movements, that is, movement to horizontal and full inversion respectively, in order to provide a clinical interpretation of impaired epiglottic function. Study Design Retrospective cohort study. Methods A heterogeneous cohort of patients with swallowing difficulties was identified (n=92). Two speech-language pathologists reviewed 5ml thin and 5ml pudding videofluoroscopic swallow studies per subject, and assigned epiglottic component scores of 0=complete inversion, 1=partial inversion, and 2=no inversion forming three groups of videos for comparison. Coordinates mapping minimum and maximum excursion of the hyoid, pharynx, larynx, and tongue base during pharyngeal swallowing were recorded using ImageJ software. A canonical variate analysis with post-hoc discriminant function analysis of coordinates was performed using MorphoJ software to evaluate mechanical differences between groups. Eigenvectors characterizing swallowing mechanics underlying impaired epiglottic movements were visualized. Results Nineteen of 184 video-swallows were rejected for poor quality (n=165). A Goodman-Kruskal index of predictive association showed no correlation between epiglottic component scores and etiologies of dysphagia (λ=.04). A two-way analysis of variance by epiglottic component scores showed no significant interaction effects between sex and age (f=1.4, p=.25). Discriminant function analysis demonstrated statistically significant mechanical differences between epiglottic component scores: 1&2, representing the first epiglottic movement (Mahalanobis distance=1.13, p=.0007); and, 0&1, representing the second epiglottic movement (Mahalanobis distance=0.83, p=.003). Eigenvectors indicate that laryngeal elevation and tongue base retraction underlie both epiglottic movements. Conclusion Results suggest that reduced tongue base retraction and laryngeal elevation underlie impaired first and second epiglottic movements. The styloglossus, hyoglossus and long pharyngeal muscles are implicated as targets for rehabilitation in dysphagic patients with impaired epiglottic inversion. PMID:27426940

  1. Evidence that meiotic pairing starts at the telomeres: Molecular analysis of recombination in a family with a pericentric X chromosome inversion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shashi, V.; Allinson, P.S.; Golden, W.L.

    1994-09-01

    Recent studies in yeast have shown that telomeres rather than centromeres lead in chromosome movement just prior to meiosis and may have a role in recombination. Cytological studies of meiosis in Drosophila and mice have shown that in pericentric inversion heterozygotes there is lack of loop formation, with recobmination seen only outside the inversion. In a family with Duchenne muscular dystrophy (DMD) we recognized that only affected males and carrier females had a pericentric X chromosome inversion (inv X(p11.4;q26)). Since the short arm inversion breakpoint was proximal to the DMD locus, it could not be implicated in the mutational eventmore » causing DMD. There was no history of infertility, recurrent miscarriages or liveborn unbalanced females to suggest there was recombination within the inversion. We studied 22 members over three generations to understand the pattern of meiotic recombination between the normal and the inverted X chromosome. In total, 17 meioses involving the inverted X chromosome in females were studied by cytogenetic analysis and 16 CA repeat polymorphisms along the length of the X chromosome. Results: (a) There was complete concordance between the segregation of the DMD mutation and the inverted X chromosome. (b) On DNA analysis, there was complete absence of recombination within the inverted segment. We also found no recombination at the DMD locus. Recombination was seen only at Xp22 and Xq27-28. (c) Recombination was seen in the same individual at both Xp22 and Xq27-28 without recombination otherwise. Conclusions: (1) Pericentric X inversions reduce the genetic map length of the chromosome, with the physical map length being normal. (2) Meiotic X chromosome pairing in this family is initiated at the telomeres. (3) Following telomeric pairing in pericentric X chromosome inversions, there is inhibition of recombination within the inversion and adjacent regions.« less

  2. Risk factors associated with the carotid intima-media thickness and plaques: ESPREDIA Study.

    PubMed

    Mostaza, Jose M; Lahoz, Carlos; Salinero-Fort, Miguel A; Laguna, Fernando; Estirado, Eva; García-Iglesias, Francisca; González Alegre, Teresa; Sabín, Concesa; López, Silvia; Cornejo, Victor

    To evaluate whether there were any differences in the risk factor profile associated with either the intima-media thickness (IMT) or the presence of carotid plaques. Cross-sectional study in 1475 subjects between 45 and 75years, randomly selected from the population of the Northwest area of Madrid (Spain). They had a physical exam, blood analysis, and ultrasound measurement of the IMT and of the presence of plaques. Mean IMT was 0.725±0.132mm. Forty seven percent of the participants had carotid plaques. In multivariate analysis, factors directly associated with the IMT were, age (β0.227, P<.0001), sex (β0.104, P<.0001), presence of hypertension (β0.082, P=.002), diabetes (β0.130, P<.0001) and current smoking (β0.107, P<.0001), systolic blood pressure (SBP) (β0.219, P<.0001) and LDL-cholesterol levels (β0.074, P=.003), and inversely, diastolic blood pressure (DBP) (β-0.124, P=.001), HDL-cholesterol (β-0.111, P<.0001) and triglyceride levels (β-0.060, P=.028). The presence of plaques was directly associated with age (OR1.08; 95%CI: 1.05-1.10), sex (OR1.95; 95%CI: 1.52-2.51), current smoking (OR2.75; 95%CI: 1.92-3.95), history of hypertension (OR1.58; 95%CI: 1.22-2.04) or diabetes (OR1.84; 95%CI: 1.31-2.58), statin treatment (OR1.56; 95%CI: 1.19-2.04) and SBP (OR1.03; 95%CI: 1.02-1.05), and inversely with DBP (OR0.98; 95%CI: 0.96-0.99). Factors associated with the IMT and the presence of plaques are similar, a finding that support a continuum between muscular layer hypertrophy and arteriosclerosis development. Copyright © 2017 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. High birth weight and perinatal mortality among siblings: A register based study in Norway, 1967-2011.

    PubMed

    Kristensen, Petter; Keyes, Katherine M; Susser, Ezra; Corbett, Karina; Mehlum, Ingrid Sivesind; Irgens, Lorentz M

    2017-01-01

    Perinatal mortality according to birth weight has an inverse J-pattern. Our aim was to estimate the influence of familial factors on this pattern, applying a cohort sibling design. We focused on excess mortality among macrosomic infants (>2 SD above the mean) and hypothesized that the birth weight-mortality association could be explained by confounding shared family factors. We also estimated how the participant's deviation from mean sibling birth weight influenced the association. We included 1 925 929 singletons, born term or post-term to mothers with more than one delivery 1967-2011 registered in the Medical Birth Registry of Norway. We examined z-score birth weight and perinatal mortality in random-effects and sibling fixed-effects logistic regression models including measured confounders (e.g. maternal diabetes) as well as unmeasured shared family confounders (through fixed effects models). Birth weight-specific mortality showed an inverse J-pattern, being lowest (2.0 per 1000) at reference weight (z-score +1 to +2) and increasing for higher weights. Mortality in the highest weight category was 15-fold higher than reference. This pattern changed little in multivariable models. Deviance from mean sibling birth weight modified the mortality pattern across the birth weight spectrum: small and medium-sized infants had increased mortality when being smaller than their siblings, and large-sized infants had an increased risk when outweighing their siblings. Maternal diabetes and birth weight acted in a synergistic fashion with mortality among macrosomic infants in diabetic pregnancies in excess of what would be expected for additive effects. The inverse J-pattern between birth weight and mortality is not explained by measured confounders or unmeasured shared family factors. Infants are at particularly high mortality risk when their birth weight deviates substantially from their siblings. Sensitivity analysis suggests that characteristics related to maternal diabetes could be important in explaining the increased mortality among macrosomic infants.

  4. Potent influence of obesity on suppression of plasma B-type natriuretic peptide levels in patients with acute heart failure: An approach using covariance structure analysis.

    PubMed

    Kinoshita, Koji; Kawai, Makoto; Minai, Kosuke; Ogawa, Kazuo; Inoue, Yasunori; Yoshimura, Michihiro

    2016-07-15

    Plasma B-type natriuretic peptide (BNP) levels may vary widely among patients with similar stages of heart failure, in whom obesity might be the only factor reducing plasma BNP levels. We investigated the effect of obesity and body mass index (BMI) on plasma BNP levels using serial measurements before and after treatment (pre- and post-BNP and pre- and post-BMI) in patients with acute heart failure. Multiple regression analysis and covariance structure analysis were performed to study the interactions between clinical factors in 372 patients. The pre-BMI was shown as a combination index of obesity and fluid accumulation, whereas the post-BMI was a conventional index of obesity. There was a significant inverse correlation between BMI and BNP in each condition before and after treatment for heart failure. The direct significant associations of the log pre-BNP with the log post-BNP (β: 0.387), the post-BMI (β: -0.043), and the pre-BMI (β: 0.030) were analyzed by using structural equation modeling. The post-BMI was inversely correlated, but importantly, the pre-BMI was positively correlated, with the log pre-BNP, because the pre-BMI probably entailed an element of fluid accumulation. There were few patients with extremely high levels of pre-BNP among those with high post-BMI, due to suppressed secretion of BNP. The low plasma BNP levels in true obesity patients with acute heart failure are of concern, because plasma BNP cannot increase in such patients. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  5. The relationship between emotional intelligence and job stress in the faculty of medicine in Isfahan University of Medical Sciences

    PubMed Central

    YAMANI, NIKOO; SHAHABI, MARYAM; HAGHANI, FARIBA

    2014-01-01

    Introduction: health care professionals especially clinicians, undergo lots of job stress (JS). Emotional intelligence (EI) is among the variables that appear to be associated with stress. It is also included among the ways adopted by the individuals in order to resist JS in the workplace. Thus, this study aims to investigate the relationship between EI and JS in the faculty members of Isfahan University of Medical Sciences (IUMS). Methods: This was a correlational study performed on 202 faculty members of IUMS. The data was gathered through two valid and reliable questionnaires (Bradberry EI questionnaire and JS questionnaire), being analyzed by SPSS software using descriptive statistics, Pearson correlation coefficient, t-test, analysis of variance (ANOVA) and linear regression analysis (α=0.05). Results: 142 individuals (70.30%) filled out the questionnaires. 75% of the respondents were male and 98% were married. There was an inverse correlation between the total score of EI and the level of JS (r=-0.235, p=0.005). Moreover, among the factors of EI, self-awareness and self-management scores had significant inverse relationship with the level of JS. Linear regression analysis showed that the EI factors explained approximately 7% of the variance of JS levels of the teachers. Conclusions: Individuals with high EI have less JS. Since the EI can be taught, it can be expected that the JS of faculty members can be reduced through training them on emotional intelligence. Therefore, it is recommended that short-term training courses be scheduled and designed based on the concepts of EI for teachers, particularly clinicians. PMID:25512914

  6. Influence of climate variability on acute myocardial infarction mortality in Havana, 2001-2012.

    PubMed

    Rivero, Alina; Bolufé, Javier; Ortiz, Paulo L; Rodríguez, Yunisleydi; Reyes, María C

    2015-04-01

    Death from acute myocardial infarction is due to many factors; influences on risk to the individual include habits, lifestyle and behavior, as well as weather, climate and other environmental components. Changing climate patterns make it especially important to understand how climatic variability may influence acute myocardial infarction mortality. Describe the relationship between climate variability and acute myocardial infarction mortality during the period 2001-2012 in Havana. An ecological time-series study was conducted. The universe comprised 23,744 deaths from acute myocardial infarction (ICD-10: I21-I22) in Havana residents from 2001 to 2012. Climate variability and seasonal anomalies were described using the Bultó-1 bioclimatic index (comprising variables of temperature, humidity, precipitation, and atmospheric pressure), along with series analysis to determine different seasonal-to-interannual climate variation signals. The role played by climate variables in acute myocardial infarction mortality was determined using factor analysis. The Mann-Kendall and Pettitt statistical tests were used for trend analysis with a significance level of 5%. The strong association between climate variability conditions described using the Bultó-1 bioclimatic index and acute myocardial infarctions accounts for the marked seasonal pattern in AMI mortality. The highest mortality rate occurred during the dry season, i.e., the winter months in Cuba (November-April), with peak numbers in January, December and March. The lowest mortality coincided with the rainy season, i.e., the summer months (May-October). A downward trend in total number of deaths can be seen starting with the change point in April 2009. Climate variability is inversely associated with an increase in acute myocardial infarction mortality as is shown by the Bultó-1 index. This inverse relationship accounts for acute myocardial infarction mortality's seasonal pattern.

  7. Statistical power in parallel group point exposure studies with time-to-event outcomes: an empirical comparison of the performance of randomized controlled trials and the inverse probability of treatment weighting (IPTW) approach.

    PubMed

    Austin, Peter C; Schuster, Tibor; Platt, Robert W

    2015-10-15

    Estimating statistical power is an important component of the design of both randomized controlled trials (RCTs) and observational studies. Methods for estimating statistical power in RCTs have been well described and can be implemented simply. In observational studies, statistical methods must be used to remove the effects of confounding that can occur due to non-random treatment assignment. Inverse probability of treatment weighting (IPTW) using the propensity score is an attractive method for estimating the effects of treatment using observational data. However, sample size and power calculations have not been adequately described for these methods. We used an extensive series of Monte Carlo simulations to compare the statistical power of an IPTW analysis of an observational study with time-to-event outcomes with that of an analysis of a similarly-structured RCT. We examined the impact of four factors on the statistical power function: number of observed events, prevalence of treatment, the marginal hazard ratio, and the strength of the treatment-selection process. We found that, on average, an IPTW analysis had lower statistical power compared to an analysis of a similarly-structured RCT. The difference in statistical power increased as the magnitude of the treatment-selection model increased. The statistical power of an IPTW analysis tended to be lower than the statistical power of a similarly-structured RCT.

  8. Seasonal variation of semen parameters correlates with environmental temperature and air pollution: A big data analysis over 6 years.

    PubMed

    Santi, Daniele; Magnani, Elisa; Michelangeli, Marco; Grassi, Roberto; Vecchi, Barbara; Pedroni, Gioia; Roli, Laura; De Santis, Maria Cristina; Baraldi, Enrica; Setti, Monica; Trenti, Tommaso; Simoni, Manuela

    2018-04-01

    Male fertility is progressively declining in many developed countries, but the relationship between male infertility and environmental factors is still unclear. To assess the influence of environmental temperature and air pollution on semen parameters, using a big-data approach. A big data analysis of parameters related to 5131 men, living in a province of Northern Italy and undergoing semen analyses between January 2010 and March 2016 was performed. Ambient temperature was recorded on the day of analysis and the 90 days prior to the analysis and the average value of particulate matter (PM) and NO2 in the year of the test. All data were acquired by geocoding patients residential address. A data warehouse containing 990,904,591 data was generated and analysed by multiple regressions. 5573 semen analyses were collected. Both maximum and minimum temperatures registered on the day of collection were inversely related to total sperm number (p < .001), non-progressive motility (NPrM) (p < .005) and normal forms (p < .001). Results were confirmed considering temperature in the 30 and 60 days before collection, but not in the 90 days before collection. Total sperm number was lower in summer/autumn (p < .001) and was inversely related with daylight duration (p < .001). PM10 and PM2.5 were inversely related to PrM (p < .001 and p < .005) and abnormal forms (p < .001). This is the first evaluation of the relationship between male fertility-related parameters and environment using a big-data approach. A seasonal change in semen parameters was found, with a fluctuation related to both temperature and daylight duration. A negative correlation between air pollution and semen quality is suggested. Such seasonal and environmental associations should be considered when assessing changes of male fertility-related parameters over time. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Location error uncertainties - an advanced using of probabilistic inverse theory

    NASA Astrophysics Data System (ADS)

    Debski, Wojciech

    2016-04-01

    The spatial location of sources of seismic waves is one of the first tasks when transient waves from natural (uncontrolled) sources are analyzed in many branches of physics, including seismology, oceanology, to name a few. Source activity and its spatial variability in time, the geometry of recording network, the complexity and heterogeneity of wave velocity distribution are all factors influencing the performance of location algorithms and accuracy of the achieved results. While estimating of the earthquake foci location is relatively simple a quantitative estimation of the location accuracy is really a challenging task even if the probabilistic inverse method is used because it requires knowledge of statistics of observational, modelling, and apriori uncertainties. In this presentation we addressed this task when statistics of observational and/or modeling errors are unknown. This common situation requires introduction of apriori constraints on the likelihood (misfit) function which significantly influence the estimated errors. Based on the results of an analysis of 120 seismic events from the Rudna copper mine operating in southwestern Poland we illustrate an approach based on an analysis of Shanon's entropy calculated for the aposteriori distribution. We show that this meta-characteristic of the aposteriori distribution carries some information on uncertainties of the solution found.

  10. Effects of coffee consumption on glucose tolerance, serum glucose and insulin levels--a cross-sectional analysis.

    PubMed

    Bidel, S; Hu, G; Sundvall, J; Kaprio, J; Tuomilehto, J

    2006-01-01

    Coffee has several metabolic effects that could reduce the risk of type 2 diabetes. Our objective was to examine the effects of coffee consumption on glucose tolerance, glucose and insulin levels. A subsample of subjects aged 45 to 64 years in 1987 and in 1992 from the population-based FINRISK study (12,287 individuals) was invited to receive the standard oral glucose tolerance test at baseline. Plasma samples were taken after an overnight fast, and a two-hour oral glucose tolerance test was administered. Fasting and two-hour plasma glucose and insulin were measured in 2434 subjects with data on coffee use and potential confounders. After adjustment for potential confounding factors (age, body mass index, systolic blood pressure, occupational, commuting and leisure time physical activity, alcohol and tea drinking, smoking), coffee consumption was significantly and inversely associated with fasting glucose, two-hour plasma glucose, and fasting insulin in both men and women. Coffee consumption was significantly and inversely associated with impaired fasting glucose, impaired glucose regulation, and hyperinsulinemia among both men and women and with isolated impaired glucose tolerance among women. In this cross-sectional analysis, coffee showed positive effects on several glycemia markers.

  11. Insulin-Like Growth Factor 1 Receptor and p38 Mitogen-Activated Protein Kinase Signals Inversely Regulate Signal Transducer and Activator of Transcription 3 Activity to Control Human Dental Pulp Stem Cell Quiescence, Propagation, and Differentiation

    PubMed Central

    Vandomme, Jerome; Touil, Yasmine; Ostyn, Pauline; Olejnik, Cecile; Flamenco, Pilar; El Machhour, Raja; Segard, Pascaline; Masselot, Bernadette; Bailliez, Yves; Formstecher, Pierre

    2014-01-01

    Dental pulp stem cells (DPSCs) remain quiescent until activated in response to severe dental pulp damage. Once activated, they exit quiescence and enter regenerative odontogenesis, producing reparative dentin. The factors and signaling molecules that control the quiescence/activation and commitment to differentiation of human DPSCs are not known. In this study, we determined that the inhibition of insulin-like growth factor 1 receptor (IGF-1R) and p38 mitogen-activated protein kinase (p38 MAPK) signaling commonly activates DPSCs and promotes their exit from the G0 phase of the cell cycle as well as from the pyronin Ylow stem cell compartment. The inhibition of these two pathways, however, inversely determines DPSC fate. In contrast to p38 MAPK inhibitors, IGF-1R inhibitors enhance dental pulp cell sphere-forming capacity and reduce the cells' colony-forming capacity without inducing cell death. The inverse cellular changes initiated by IGF-1R and p38 MAPK inhibitors were accompanied by inverse changes in the levels of active signal transducer and activator of transcription 3 (STAT3) factor, inactive glycogen synthase kinase 3, and matrix extracellular phosphoglycoprotein, a marker of early odontoblast differentiation. Our data suggest that there is cross talk between the IGF-1R and p38 MAPK signaling pathways in DPSCs and that the signals provided by these pathways converge at STAT3 and inversely regulate its activity to maintain quiescence or to promote self-renewal and differentiation of the cells. We propose a working model that explains the possible interactions between IGF-1R and p38 MAPK at the molecular level and describes the cellular consequences of these interactions. This model may inspire further fundamental study and stimulate research on the clinical applications of DPSC in cellular therapy and tissue regeneration. PMID:24266654

  12. Development of direct-inverse 3-D methods for applied transonic aerodynamic wing design and analysis

    NASA Technical Reports Server (NTRS)

    Carlson, Leland A.

    1989-01-01

    An inverse wing design method was developed around an existing transonic wing analysis code. The original analysis code, TAWFIVE, has as its core the numerical potential flow solver, FLO30, developed by Jameson and Caughey. Features of the analysis code include a finite-volume formulation; wing and fuselage fitted, curvilinear grid mesh; and a viscous boundary layer correction that also accounts for viscous wake thickness and curvature. The development of the inverse methods as an extension of previous methods existing for design in Cartesian coordinates is presented. Results are shown for inviscid wing design cases in super-critical flow regimes. The test cases selected also demonstrate the versatility of the design method in designing an entire wing or discontinuous sections of a wing.

  13. Spatial distribution of intrinsic and scattering seismic attenuation in active volcanic islands - I: model and the case of Tenerife Island

    NASA Astrophysics Data System (ADS)

    Prudencio, Janire; Del Pezzo, Edoardo; García-Yeguas, Araceli; Ibáñez, Jesús M.

    2013-12-01

    The complex volcanic system of Tenerife Island is known to have a highly heterogeneous character, as recently confirmed by velocity tomography. We present new information derived from intrinsic quality factor inverse maps (Qi-1), scattering quality factor inverse maps (Qs-1) and total quality factor inverse maps (Qt-1) obtained for the same region. The data set used in this work is the result of the analysis of an active seismic experiment carried out, using offshore shots (air guns) recorded at over 85 onshore seismic stations. The estimates of the attenuation parameters are based on the assumption that the seismogram energy envelopes are determined by seismic energy diffusion processes occurring inside the island. Diffusion model parameters, proportional to Qi-1 and to Qs-1, are estimated from the inversion of the energy envelopes for any source-receiver couple. They are then weighted with a new graphical approach based on a Gaussian space probability function, which allowed us to create `2-D probabilistic maps' representing the space distribution of the attenuation parameters. The 2-D images obtained reveal the existence of a zone in the centre of the island characterized by the lowest attenuation effects. This effect is interpreted as highly rigid and cooled rocks. This low-attenuation region is bordered by zones of high attenuation, associated with the recent historical volcanic activity. We calculate the transport mean free path obtaining a value of around 4 km for the frequency range 6-12 Hz. This result is two orders of magnitude smaller than values calculated for the crust of the Earth. An absorption length between 10 and 14 km is associated with the average intrinsic attenuation parameter. These values, while small in the context of tectonic regions, are greater than those obtained in volcanic regions such as Vesuvius or Merapi. Such differences may be explained by the magnitude of the region of study, over three times larger than the aforementioned study areas. This also implies deeper sampling of the crust, which is evidenced by a change in the values of seismic attenuation. One important observation is that scattering attenuation dominates over the intrinsic effects, Qi being at least twice the value of Qs.

  14. Inverse analysis of aerodynamic loads from strain information using structural models and neural networks

    NASA Astrophysics Data System (ADS)

    Wada, Daichi; Sugimoto, Yohei

    2017-04-01

    Aerodynamic loads on aircraft wings are one of the key parameters to be monitored for reliable and effective aircraft operations and management. Flight data of the aerodynamic loads would be used onboard to control the aircraft and accumulated data would be used for the condition-based maintenance and the feedback for the fatigue and critical load modeling. The effective sensing techniques such as fiber optic distributed sensing have been developed and demonstrated promising capability of monitoring structural responses, i.e., strains on the surface of the aircraft wings. By using the developed techniques, load identification methods for structural health monitoring are expected to be established. The typical inverse analysis for load identification using strains calculates the loads in a discrete form of concentrated forces, however, the distributed form of the loads is essential for the accurate and reliable estimation of the critical stress at structural parts. In this study, we demonstrate an inverse analysis to identify the distributed loads from measured strain information. The introduced inverse analysis technique calculates aerodynamic loads not in a discrete but in a distributed manner based on a finite element model. In order to verify the technique through numerical simulations, we apply static aerodynamic loads on a flat panel model, and conduct the inverse identification of the load distributions. We take two approaches to build the inverse system between loads and strains. The first one uses structural models and the second one uses neural networks. We compare the performance of the two approaches, and discuss the effect of the amount of the strain sensing information.

  15. Geoacoustic inversion with two source-receiver arrays in shallow water.

    PubMed

    Sukhovich, Alexey; Roux, Philippe; Wathelet, Marc

    2010-08-01

    A geoacoustic inversion scheme based on a double beamforming algorithm in shallow water is proposed and tested. Double beamforming allows identification of multi-reverberated eigenrays propagating between two vertical transducer arrays according to their emission and reception angles and arrival times. Analysis of eigenray intensities yields the bottom reflection coefficient as a function of angle of incidence. By fitting the experimental reflection coefficient with a theoretical prediction, values of the acoustic parameters of the waveguide bottom can be extracted. The procedure was initially tested in a small-scale tank experiment for a waveguide with a Plexiglas bottom. Inversion results for the speed of shear waves in Plexiglas are in good agreement with the table values. A similar analysis was applied to data collected during an at-sea experiment in shallow coastal waters of the Mediterranean. Bottom reflection coefficient was fitted with the theory in which bottom sediments are modeled as a multi-layered system. Retrieved bottom parameters are in quantitative agreement with those determined from a prior inversion scheme performed in the same area. The present study confirms the interest in processing source-receiver array data through the double beamforming algorithm, and indicates the potential for application of eigenray intensity analysis to geoacoustic inversion problems.

  16. Resolution of VTI anisotropy with elastic full-waveform inversion: theory and basic numerical examples

    NASA Astrophysics Data System (ADS)

    Podgornova, O.; Leaney, S.; Liang, L.

    2018-07-01

    Extracting medium properties from seismic data faces some limitations due to the finite frequency content of the data and restricted spatial positions of the sources and receivers. Some distributions of the medium properties make low impact on the data (including none). If these properties are used as the inversion parameters, then the inverse problem becomes overparametrized, leading to ambiguous results. We present an analysis of multiparameter resolution for the linearized inverse problem in the framework of elastic full-waveform inversion. We show that the spatial and multiparameter sensitivities are intertwined and non-sensitive properties are spatial distributions of some non-trivial combinations of the conventional elastic parameters. The analysis accounts for the Hessian information and frequency content of the data; it is semi-analytical (in some scenarios analytical), easy to interpret and enhances results of the widely used radiation pattern analysis. Single-type scattering is shown to have limited sensitivity, even for full-aperture data. Finite-frequency data lose multiparameter sensitivity at smooth and fine spatial scales. Also, we establish ways to quantify a spatial-multiparameter coupling and demonstrate that the theoretical predictions agree well with the numerical results.

  17. Multi-GPU parallel algorithm design and analysis for improved inversion of probability tomography with gravity gradiometry data

    NASA Astrophysics Data System (ADS)

    Hou, Zhenlong; Huang, Danian

    2017-09-01

    In this paper, we make a study on the inversion of probability tomography (IPT) with gravity gradiometry data at first. The space resolution of the results is improved by multi-tensor joint inversion, depth weighting matrix and the other methods. Aiming at solving the problems brought by the big data in the exploration, we present the parallel algorithm and the performance analysis combining Compute Unified Device Architecture (CUDA) with Open Multi-Processing (OpenMP) based on Graphics Processing Unit (GPU) accelerating. In the test of the synthetic model and real data from Vinton Dome, we get the improved results. It is also proved that the improved inversion algorithm is effective and feasible. The performance of parallel algorithm we designed is better than the other ones with CUDA. The maximum speedup could be more than 200. In the performance analysis, multi-GPU speedup and multi-GPU efficiency are applied to analyze the scalability of the multi-GPU programs. The designed parallel algorithm is demonstrated to be able to process larger scale of data and the new analysis method is practical.

  18. Iterative inversion of deformation vector fields with feedback control.

    PubMed

    Dubey, Abhishek; Iliopoulos, Alexandros-Stavros; Sun, Xiaobai; Yin, Fang-Fang; Ren, Lei

    2018-05-14

    Often, the inverse deformation vector field (DVF) is needed together with the corresponding forward DVF in four-dimesional (4D) reconstruction and dose calculation, adaptive radiation therapy, and simultaneous deformable registration. This study aims at improving both accuracy and efficiency of iterative algorithms for DVF inversion, and advancing our understanding of divergence and latency conditions. We introduce a framework of fixed-point iteration algorithms with active feedback control for DVF inversion. Based on rigorous convergence analysis, we design control mechanisms for modulating the inverse consistency (IC) residual of the current iterate, to be used as feedback into the next iterate. The control is designed adaptively to the input DVF with the objective to enlarge the convergence area and expedite convergence. Three particular settings of feedback control are introduced: constant value over the domain throughout the iteration; alternating values between iteration steps; and spatially variant values. We also introduce three spectral measures of the displacement Jacobian for characterizing a DVF. These measures reveal the critical role of what we term the nontranslational displacement component (NTDC) of the DVF. We carry out inversion experiments with an analytical DVF pair, and with DVFs associated with thoracic CT images of six patients at end of expiration and end of inspiration. The NTDC-adaptive iterations are shown to attain a larger convergence region at a faster pace compared to previous nonadaptive DVF inversion iteration algorithms. By our numerical experiments, alternating control yields smaller IC residuals and inversion errors than constant control. Spatially variant control renders smaller residuals and errors by at least an order of magnitude, compared to other schemes, in no more than 10 steps. Inversion results also show remarkable quantitative agreement with analysis-based predictions. Our analysis captures properties of DVF data associated with clinical CT images, and provides new understanding of iterative DVF inversion algorithms with a simple residual feedback control. Adaptive control is necessary and highly effective in the presence of nonsmall NTDCs. The adaptive iterations or the spectral measures, or both, may potentially be incorporated into deformable image registration methods. © 2018 American Association of Physicists in Medicine.

  19. Perceived Social Ecological Factors Associated with Fruit and Vegetable Purchasing, Preparation, and Consumption among Young Adults

    PubMed Central

    Graham, Dan J.; Pelletier, Jennifer; Neumark-Sztainer, Dianne; Lust, Katherine; Laska, Melissa N.

    2013-01-01

    Most young adults do not consume recommended levels of fruits and vegetables (FV), and interventions to increase FV-related behaviors among this understudied population are needed. Therefore, it is important to identify correlates of FV intake among young adults to guide intervention development. This cross-sectional study utilized data from an online survey to identify factors related to young adults’ FV purchasing, preparation, and consumption, and to explore between-factor relationships using mediation analysis. In 2010, 1201 college students in Minnesota completed questionnaires assessing FV behaviors, as well as perceptions of FV-related individual, social, and environmental factors. Factor analysis identified questionnaire items assessing similar constructs. Seven factors were identified (personal barriers, FV knowledge, family, friends, neighborhood, access barriers, and campus) and evaluated for relationships with FV purchasing, preparation, and consumption using linear regression. Results revealed that perceived personal barriers (e.g., lacking cooking skills) were inversely related to all FV outcomes. Perception that family and friends eat healthfully and neighborhood access to FV were positively related to all outcomes. Individual-, social-, and environmental-level perceptions were related to purchasing, preparation, and consumption, and the effects of these factors were similar when accounting for mediated effects. Factors at all three levels and the ways in which these various factors operate together may be important to consider in future efforts to improve FV behaviors among young adults. PMID:23958116

  20. Simultaneous Gaussian and exponential inversion for improved analysis of shales by NMR relaxometry

    USGS Publications Warehouse

    Washburn, Kathryn E.; Anderssen, Endre; Vogt, Sarah J.; Seymour, Joseph D.; Birdwell, Justin E.; Kirkland, Catherine M.; Codd, Sarah L.

    2014-01-01

    Nuclear magnetic resonance (NMR) relaxometry is commonly used to provide lithology-independent porosity and pore-size estimates for petroleum resource evaluation based on fluid-phase signals. However in shales, substantial hydrogen content is associated with solid and fluid signals and both may be detected. Depending on the motional regime, the signal from the solids may be best described using either exponential or Gaussian decay functions. When the inverse Laplace transform, the standard method for analysis of NMR relaxometry results, is applied to data containing Gaussian decays, this can lead to physically unrealistic responses such as signal or porosity overcall and relaxation times that are too short to be determined using the applied instrument settings. We apply a new simultaneous Gaussian-Exponential (SGE) inversion method to simulated data and measured results obtained on a variety of oil shale samples. The SGE inversion produces more physically realistic results than the inverse Laplace transform and displays more consistent relaxation behavior at high magnetic field strengths. Residuals for the SGE inversion are consistently lower than for the inverse Laplace method and signal overcall at short T2 times is mitigated. Beyond geological samples, the method can also be applied in other fields where the sample relaxation consists of both Gaussian and exponential decays, for example in material, medical and food sciences.

  1. Relationship of type of work with health-related quality of life.

    PubMed

    Kawabe, Yuri; Nakamura, Yasuyuki; Kikuchi, Sayuri; Suzukamo, Yoshimi; Murakami, Yoshitaka; Tanaka, Taichiro; Takebayashi, Toru; Okayama, Akira; Miura, Katsuyuki; Okamura, Tomonori; Fukuhara, Shunichi; Ueshima, Hirotsugu

    2015-12-01

    To examine the relation of work type with health-related quality of life (HRQoL) in healthy workers. We cross-sectionally examined 4427 (3605 men and 822 women) healthy workers in Japan, aged 19-69 years. We assessed HRQoL based on scores for five scales of the SF-36. Multiple regression was applied to examine the relation of work type (nighttime, shift, day to night, and daytime) with the five HRQoL norm-based scores, lower scores of which indicate poorer health status, adjusted for confounding factors, including sleeping duration. Shiftwork was inversely related to role physical [regression estimate (β) = -2.12, 95 % confidence intervals (CI) -2.94, -1.30, P < 0.001], general health (β = -1.37, 95 % CI -2.01, -0.72, P < 0.001), role emotional (β = -1.24, 95% CI -1.98, -0.50, P < 0.001), and mental health (β = -1.31, 95% CI -2.01, -0.63, P < 0.001) independent of confounding factors, but not to vitality. Day-to-nighttime work was inversely related to all the five HRQoL subscales (Ps 0.012 to <0.001). Shiftwork was significantly inversely related to four out of the five HRQoL, except for vitality, and day-to-nighttime work was significantly inversely related to all five HRQoL, independent of demographic and lifestyle factors.

  2. The association of personal importance of religion and religious service attendance with suicidal ideation by age group in the National Survey on Drug Use and Health.

    PubMed

    Nishi, Daisuke; Susukida, Ryoko; Kuroda, Naoaki; Wilcox, Holly C

    2017-09-01

    Religiosity has been shown to be inversely associated with suicidal ideation, but few studies have examined associations by age group. This study aimed to examine the association between religiosity with suicidal ideation by age group. This study used a large nationally representative sample of 260,816 study participants from the National Survey on Drug Use and Health. Religiosity was defined as self-reported importance of religious beliefs and frequency of religious service attendance. The association between religiosity and suicidal ideation was assessed by multivariable logistic regression analysis stratified by age group (18-25, 26-34, 35-49, 50-64, 65 or older). The importance of religious beliefs was inversely associated with suicidal ideation in all age groups. The association was the strongest in people aged 65 or older, followed by people aged 18-25. Religious service attendance was also inversely associated with suicidal ideation in people aged 65 or more when attendance was more than 25 times per year. These findings may be helpful to understand age in relation to the relationship between religiosity and suicidal ideation. Particular attention to religiosity among older adults as a protective factor for suicidal ideation may be helpful in clinical settings. Copyright © 2017. Published by Elsevier B.V.

  3. Identifing Atmospheric Pollutant Sources Using Artificial Neural Networks

    NASA Astrophysics Data System (ADS)

    Paes, F. F.; Campos, H. F.; Luz, E. P.; Carvalho, A. R.

    2008-05-01

    The estimation of the area source pollutant strength is a relevant issue for atmospheric environment. This characterizes an inverse problem in the atmospheric pollution dispersion. In the inverse analysis, an area source domain is considered, where the strength of such area source term is assumed unknown. The inverse problem is solved by using a supervised artificial neural network: multi-layer perceptron. The conection weights of the neural network are computed from delta rule - learning process. The neural network inversion is compared with results from standard inverse analysis (regularized inverse solution). In the regularization method, the inverse problem is formulated as a non-linear optimization approach, whose the objective function is given by the square difference between the measured pollutant concentration and the mathematical models, associated with a regularization operator. In our numerical experiments, the forward problem is addressed by a source-receptor scheme, where a regressive Lagrangian model is applied to compute the transition matrix. The second order maximum entropy regularization is used, and the regularization parameter is calculated by the L-curve technique. The objective function is minimized employing a deterministic scheme (a quasi-Newton algorithm) [1] and a stochastic technique (PSO: particle swarm optimization) [2]. The inverse problem methodology is tested with synthetic observational data, from six measurement points in the physical domain. The best inverse solutions were obtained with neural networks. References: [1] D. R. Roberti, D. Anfossi, H. F. Campos Velho, G. A. Degrazia (2005): Estimating Emission Rate and Pollutant Source Location, Ciencia e Natura, p. 131-134. [2] E.F.P. da Luz, H.F. de Campos Velho, J.C. Becceneri, D.R. Roberti (2007): Estimating Atmospheric Area Source Strength Through Particle Swarm Optimization. Inverse Problems, Desing and Optimization Symposium IPDO-2007, April 16-18, Miami (FL), USA, vol 1, p. 354-359.

  4. Comparison of data inversion techniques for remotely sensed wide-angle observations of Earth emitted radiation

    NASA Technical Reports Server (NTRS)

    Green, R. N.

    1981-01-01

    The shape factor, parameter estimation, and deconvolution data analysis techniques were applied to the same set of Earth emitted radiation measurements to determine the effects of different techniques on the estimated radiation field. All three techniques are defined and their assumptions, advantages, and disadvantages are discussed. Their results are compared globally, zonally, regionally, and on a spatial spectrum basis. The standard deviations of the regional differences in the derived radiant exitance varied from 7.4 W-m/2 to 13.5 W-m/2.

  5. 3D magnetotelluric inversion system with static shift correction and theoretical assessment in oil and gas exploration

    NASA Astrophysics Data System (ADS)

    Dong, H.; Kun, Z.; Zhang, L.

    2015-12-01

    This magnetotelluric (MT) system contains static shift correction and 3D inversion. The correction method is based on the data study on 3D forward modeling and field test. The static shift can be detected by the quantitative analysis of apparent parameters (apparent resistivity and impedance phase) of MT in high frequency range, and completed correction with inversion. The method is an automatic processing technology of computer with zero-cost, and avoids the additional field work and indoor processing with good results shown in Figure 1a-e. Figure 1a shows a normal model (I) without any local heterogeneity. Figure 1b shows a static-shifted model (II) with two local heterogeneous bodies (10 and 1000 ohm.m). Figure 1c is the inversion result (A) for the synthetic data generated from model I. Figure 1d is the inversion result (B) for the static-shifted data generated from model II. Figure 1e is the inversion result (C) for the static-shifted data from model II, but with static shift correction. The results show that the correction method is useful. The 3D inversion algorithm is improved base on the NLCG method of Newman & Alumbaugh (2000) and Rodi & Mackie (2001). For the algorithm, we added the frequency based parallel structure, improved the computational efficiency, reduced the memory of computer, added the topographic and marine factors, and added the constraints of geology and geophysics. So the 3D inversion could even work in PAD with high efficiency and accuracy. The application example of theoretical assessment in oil and gas exploration is shown in Figure 1f-i. The synthetic geophysical model consists of five layers (from top to downwards): shale, limestone, gas, oil, groundwater and limestone overlying a basement rock. Figure 1f-g show the 3D model and central profile. Figure 1h shows the centrel section of 3D inversion, the resultsd show a high degree of reduction in difference on the synthetic model. Figure 1i shows the seismic waveform reflects the interfaces of every layer overall, but the relative positions of the interface of the two-way travel time vary, and the interface between limestone and oil at the sides of the section is not reflected. So 3-D MT can make up for the deficiency of the seismic results such as the fake sync-phase axis and multiple waves.

  6. Forest Canopy Cover and Height from MISR in Topographically Complex Southwestern US Landscape Assessed with High Quality Reference Data

    NASA Technical Reports Server (NTRS)

    Chopping, Mark; North, Malcolm; Chen, Jiquan; Schaaf, Crystal B.; Blair, J. Bryan; Martonchik, John V.; Bull, Michael A.

    2012-01-01

    This study addresses the retrieval of spatially contiguous canopy cover and height estimates in southwestern USforests via inversion of a geometric-optical (GO) model against surface bidirectional reflectance factor (BRF) estimates from the Multi-angle Imaging SpectroRadiometer (MISR). Model inversion can provide such maps if good estimates of the background bidirectional reflectance distribution function (BRDF) are available. The study area is in the Sierra National Forest in the Sierra Nevada of California. Tree number density, mean crown radius, and fractional cover reference estimates were obtained via analysis of QuickBird 0.6 m spatial resolution panchromatic imagery usingthe CANopy Analysis with Panchromatic Imagery (CANAPI) algorithm, while RH50, RH75 and RH100 (50, 75, and 100 energy return) height data were obtained from the NASA Laser Vegetation Imaging Sensor (LVIS), a full waveform light detection and ranging (lidar) instrument. These canopy parameters were used to drive a modified version of the simple GO model (SGM), accurately reproducing patterns ofMISR 672 nm band surface reflectance (mean RMSE 0.011, mean R2 0.82, N 1048). Cover and height maps were obtained through model inversion against MISR 672 nm reflectance estimates on a 250 m grid.The free parameters were tree number density and mean crown radius. RMSE values with respect to reference data for the cover and height retrievals were 0.05 and 6.65 m, respectively, with of 0.54 and 0.49. MISR can thus provide maps of forest cover and height in areas of topographic variation although refinements are required to improve retrieval precision.

  7. Socio-demographic and lifestyle determinants of dietary patterns in French-speaking Switzerland, 2009-2012.

    PubMed

    Marques-Vidal, Pedro; Waeber, Gérard; Vollenweider, Peter; Guessous, Idris

    2018-01-12

    Food intake is a complex behaviour which can be assessed using dietary patterns. Our aim was to characterize dietary patterns and associated factors in French-speaking Switzerland. Cross-sectional study conducted between 2009 and 2012 in the city of Lausanne, Switzerland, including 4372 participants (54% women, 57.3 ± 10.3 years). Food consumption was assessed using a validated food frequency questionnaire. Dietary patterns were assessed by principal components analysis. Three patterns were identified: "Meat & fries"; "Fruits & Vegetables" and "Fatty & sugary". The "Meat & fries" pattern showed the strongest correlations with total and animal protein and cholesterol carbohydrates, dietary fibre and calcium. The "Fruits & Vegetables" pattern showed the strongest correlations with dietary fibre, carotene and vitamin D. The "Fatty & sugary" pattern showed the strongest correlations with total energy and saturated fat. On multivariate analysis, male gender, low educational level and sedentary status were positively associated with the "Meat & fries" and the "Fatty & sugary" patterns, and negatively associated with the "Fruits & Vegetables" pattern. Increasing age was inversely associated with the "Meat & fries" pattern; smoking status was inversely associated with the "Fruits & Vegetables" pattern. Being born in Portugal or Spain was positively associated with the "Meat & fries" and the "Fruits & Vegetables" patterns. Increasing body mass index was positively associated with the "Meat & fries" pattern and inversely associated with the "Fatty & sugary" pattern. Three dietary patterns, one healthy and two unhealthy, were identified in the Swiss population. Several associated modifiable behaviours were identified; the information on socio- demographic determinants allows targeting of the most vulnerable groups in the context of public health interventions.

  8. Chromosomal evolution in the Drosophila cardini group (Diptera: Drosophilidae): photomaps and inversion analysis.

    PubMed

    Cordeiro, Juliana; De Toni, Daniela Cristina; da Silva, Gisele de Souza; Valente, Vera Lucia da Silva

    2014-10-01

    Detailed chromosome photomaps are the first step to develop further chromosomal analysis to study the evolution of the genetic architecture in any set of species, considering that chromosomal rearrangements, such as inversions, are common features of genome evolution. In this report, we analyzed inversion polymorphisms in 25 different populations belonging to six neotropical species in the cardini group: Drosophila cardini, D. cardinoides, D. neocardini, D. neomorpha, D. parthenogenetica and D. polymorpha. Furthermore, we present the first reference photomaps for the Neotropical D. cardini and D. parthenogenetica and improved photomaps for D. cardinoides, D. neocardini and D. polymorpha. We found 19 new inversions for these species. An exhaustive pairwise comparison of the polytene chromosomes was conducted for the six species in order to understand evolutionary patterns of their chromosomes.

  9. Effects of blood lead levels on airflow limitations in Korean adults: Findings from the 5th KNHNES 2011

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chung, Hye Kyung; Chang, Yoon Soo, E-mail: yschang@yuhs.ac; Ahn, Chul Woo

    This study aimed to examine whether blood levels of heavy metals, such as lead, mercury and cadmium, are related with pulmonary function in Korean adults. This investigation included 870 Korean adults (≥40 years) who received pulmonary function testing in the Korea National Health and Nutrition Examination Survey (KNHANES) V-2, 2011. Data of blood levels of heavy metals, pulmonary function tests and anthropometric measurements were acquired. Blood lead levels showed inverse correlations with the FEV{sub 1}/FVC ratio before (r=−0.276, p<0.001) and after adjustment of multiple compounding factors (r=−0.115, p=0.001). A logistic multiple regression analysis revealed that blood lead levels were amore » significant influencing factor for the FEV{sub 1}/FVC ratio (β=−0.017, p=0.001, adjusted R{sup 2}=0.267). The odds ratios (ORs) for the FEV{sub 1}/FVC ratio were significantly lower in the highest tertile group of the blood lead levels than in the lowest tertile group in Model 1 (OR=0.007, 95% CI=0.000−0.329) and Model 2 (OR=0.006, 95% CI=0.000−0.286). These findings imply that environmental exposure to lead might be an important factor that may cause airflow limitations in Korean adults. - Highlights: • Blood lead levels showed inverse correlations with the FEV{sub 1}/FVC ratio. • Blood lead level was a significant influencing factor for the FEV{sub 1}/FVC ratio. • ORs for FEV{sub 1}/FVC were lower in the highest blood lead group than in the lowest group. • Environmental exposure to lead might be an important factor for airflow limitations.« less

  10. Global Distribution of Outbreaks of Water-Associated Infectious Diseases

    PubMed Central

    Yang, Kun; LeJeune, Jeffrey; Alsdorf, Doug; Lu, Bo; Shum, C. K.; Liang, Song

    2012-01-01

    Background Water plays an important role in the transmission of many infectious diseases, which pose a great burden on global public health. However, the global distribution of these water-associated infectious diseases and underlying factors remain largely unexplored. Methods and Findings Based on the Global Infectious Disease and Epidemiology Network (GIDEON), a global database including water-associated pathogens and diseases was developed. In this study, reported outbreak events associated with corresponding water-associated infectious diseases from 1991 to 2008 were extracted from the database. The location of each reported outbreak event was identified and geocoded into a GIS database. Also collected in the GIS database included geo-referenced socio-environmental information including population density (2000), annual accumulated temperature, surface water area, and average annual precipitation. Poisson models with Bayesian inference were developed to explore the association between these socio-environmental factors and distribution of the reported outbreak events. Based on model predictions a global relative risk map was generated. A total of 1,428 reported outbreak events were retrieved from the database. The analysis suggested that outbreaks of water-associated diseases are significantly correlated with socio-environmental factors. Population density is a significant risk factor for all categories of reported outbreaks of water-associated diseases; water-related diseases (e.g., vector-borne diseases) are associated with accumulated temperature; water-washed diseases (e.g., conjunctivitis) are inversely related to surface water area; both water-borne and water-related diseases are inversely related to average annual rainfall. Based on the model predictions, “hotspots” of risks for all categories of water-associated diseases were explored. Conclusions At the global scale, water-associated infectious diseases are significantly correlated with socio-environmental factors, impacting all regions which are affected disproportionately by different categories of water-associated infectious diseases. PMID:22348158

  11. Joint Analysis of GOCE Gravity Gradients Data with Seismological and Geodynamic Observations to Infer Mantle Properties

    NASA Astrophysics Data System (ADS)

    Metivier, L.; Greff-Lefftz, M.; Panet, I.; Pajot-Métivier, G.; Caron, L.

    2014-12-01

    Joint inversion of the observed geoid and seismic velocities has been commonly used to constrain the viscosity profile within the mantle as well as the lateral density variations. Recent satellite measurements of the second-order derivatives of the Earth's gravity potential give new possibilities to understand these mantle properties. We use lateral density variations in the Earth's mantle based on slab history or deduced from seismic tomography. The main uncertainties are the relationship between seismic velocity and density -the so-called density/velocity scaling factor- and the variation with depth of the density contrast between the cold slabs and the surrounding mantle, introduced here as a scaling factor with respect to a constant value. The geoid, gravity and gravity gradients at the altitude of the GOCE satellite (about 255 km) are derived using geoid kernels for given viscosity depth profiles. We assume a layered mantle model with viscosity and conversion factor constant in each layer, and we fix the viscosity of the lithosphere. We perform a Monte Carlo search for the viscosity and the density/velocity scaling factor profiles within the mantle which allow to fit the observed geoid, gravity and gradients of gravity. We test a 2-layer, a 3-layer and 4-layer mantle. For each model, we compute the posterior probability distribution of the unknown parameters, and we discuss the respective contributions of the geoid, gravity and gravity gradients in the inversion. Finally, for the best fit, we present the viscosity and scaling factor profiles obtained for the lateral density variations derived from seismic velocities and for slabs sinking into the mantle.

  12. Access to Care Under Physician Payment Reform: A Physician-Based Analysis

    PubMed Central

    Meadow, Ann

    1995-01-01

    This article reports physician-based measures of access to care during the 3 years surrounding the 1989 physician payment reforms. Analysis was facilitated by a new system of physician identifiers in Medicare claims. Access measures include caseload per physician and related measures of the demographic composition of physicians' clientele, the proportion of physicians performing surgical and other procedures, and the assignment rate. The caseload and assignment measures were stable or improving over time, suggesting that reforms did not harm access. Procedure performance rates tended to decline between 1992 and 1993, but reductions were inversely related to the estimated fee changes, and several may be explainable by other factors. PMID:10172615

  13. [A Meta-analysis on tea drinking and the risk of lung cancer in Chinese population].

    PubMed

    Jin, Zi-yi; Han, Ren-qiang; Liu, Ai-min; Wang, Xu-shan; Wu, Ming; Zhang, Zuo-feng; Zhao, Jin-kou

    2012-08-01

    To examine the association between tea drinking and the risk of lung cancer in Chinese population. All relevant published articles in Chinese and English literature database were identified. Meta-analysis was conducted. Combined odds ratio (OR) and 95% confidence interval (CI) were calculated to estimate the associations and dose-response relationship between tea drinking and the risk of lung cancer. Twelve studies were included. An inverse association with lung cancer was observed on tea drinkers when compared to non-tea drinkers (OR = 0.66, 95%CI: 0.49 - 0.89). Tea drinking might serve as a protective factor on lung cancer in the Chinese population.

  14. Four dimensional data assimilation (FDDA) impacts on WRF performance in simulating inversion layer structure and distributions of CMAQ-simulated winter ozone concentrations in Uintah Basin

    NASA Astrophysics Data System (ADS)

    Tran, Trang; Tran, Huy; Mansfield, Marc; Lyman, Seth; Crosman, Erik

    2018-03-01

    Four-dimensional data assimilation (FDDA) was applied in WRF-CMAQ model sensitivity tests to study the impact of observational and analysis nudging on model performance in simulating inversion layers and O3 concentration distributions within the Uintah Basin, Utah, U.S.A. in winter 2013. Observational nudging substantially improved WRF model performance in simulating surface wind fields, correcting a 10 °C warm surface temperature bias, correcting overestimation of the planetary boundary layer height (PBLH) and correcting underestimation of inversion strengths produced by regular WRF model physics without nudging. However, the combined effects of poor performance of WRF meteorological model physical parameterization schemes in simulating low clouds, and warm and moist biases in the temperature and moisture initialization and subsequent simulation fields, likely amplified the overestimation of warm clouds during inversion days when observational nudging was applied, impacting the resulting O3 photochemical formation in the chemistry model. To reduce the impact of a moist bias in the simulations on warm cloud formation, nudging with the analysis water mixing ratio above the planetary boundary layer (PBL) was applied. However, due to poor analysis vertical temperature profiles, applying analysis nudging also increased the errors in the modeled inversion layer vertical structure compared to observational nudging. Combining both observational and analysis nudging methods resulted in unrealistically extreme stratified stability that trapped pollutants at the lowest elevations at the center of the Uintah Basin and yielded the worst WRF performance in simulating inversion layer structure among the four sensitivity tests. The results of this study illustrate the importance of carefully considering the representativeness and quality of the observational and model analysis data sets when applying nudging techniques within stable PBLs, and the need to evaluate model results on a basin-wide scale.

  15. Immediate, early and late seizures after primary intracerebral hemorrhage.

    PubMed

    Qian, Cheng; Löppönen, Pekka; Tetri, Sami; Huhtakangas, Juha; Juvela, Seppo; Turtiainen, Hanna-Maria E; Bode, Michaela K; Hillbom, Matti

    2014-05-01

    Seizures after primary intracerebral hemorrhage (PICH) are significant and treatable complications, but the factors predicting immediate, early and late seizures are poorly known. We investigated characteristics and outcome with special reference to occurrence and timing of a first seizure among consecutive subjects with PICH. A population-based study was conducted in Northern Ostrobothnia, Finland, in 1993-2008 that included all patients with a first-ever primary ICH without any prior diagnosis of epilepsy. Immediate (<24h after admission), early (1-14 days) and late (>2 weeks) seizures were considered separately. Out of a total of 935 ICH patients, 51 had immediate, 21 early and 58 late seizures. The patients with seizures were significantly younger than the others and more often had a subcortical hematoma location (p<0.05). Lifestyle factors did not differ between the groups. The risk factors for immediate seizures in multivariable analysis were a low Glasgow coma scale score (GCS) on admission, subcortical location and age inversely (p<0.01). The only independent risk factor for early seizures was subcortical location (p<0.001), whereas subcortical location (p<0.001), age inversely (p<0.01) and hematoma evacuation (p<0.05) independently predicted late seizures. Immediate and early seizures predicted infectious complications (p<0.05). Patients with subcortical hematoma and of younger age are at risk for immediate seizures after primary ICH irrespective of hematoma size. Patients with immediate and early seizures more often had infectious complications. Surgery increases the risk of a late seizure after ICH. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Association of Birth Order with Cardiovascular Disease Risk Factors in Young Adulthood: A Study of One Million Swedish Men

    PubMed Central

    Jelenkovic, Aline; Silventoinen, Karri; Tynelius, Per; Myrskylä, Mikko; Rasmussen, Finn

    2013-01-01

    Background Birth order has been suggested to be linked to several cardiovascular disease (CVD) risk factors, but the evidence is still inconsistent. We aim to determine the associations of birth order with body mass index (BMI), muscle strength and blood pressure. Further we will analyse whether these relationships are affected by family characteristics. Methods BMI, elbow flexion, hand grip and knee extension strength and systolic and diastolic blood pressure were measured at conscription examination in 1 065 710 Swedish young men born between 1951 and 1975. The data were analysed using linear multivariate and fixed effects regression models; the latter compare siblings and account for genetic and social factors shared by brothers. Results Fixed effect regression analysis showed that birth order was inversely associated with BMI: second and third born had 0.8% and 1.1% (p<0.001) lower BMI than first-born, respectively. The association pattern differed among muscle strengths. After adjustment for BMI, first-born presented lower elbow flexion and hand grip strength than second-born (−5.9 N and −3.8 N, respectively, p<0.001). Knee extension strength was inversely related to birth order though not always significantly. The association between birth order and blood pressure was not significant. Conclusions Birth order is negatively associated with BMI and knee extension strength, positively with elbow flexion and hand grip strength, and is not associated with blood pressure among young men. Although the effects are small, the link between birth order and some CVD risk factors is already detectable in young adulthood. PMID:23696817

  17. Use of global assays to understand clinical phenotype in congenital factor VII deficiency.

    PubMed

    Greene, L A; Goldenberg, N A; Simpson, M L; Villalobos-Menuey, E; Bombardier, C; Acharya, S S; Santiago-Borrero, P J; Cambara, A; DiMichele, D M

    2013-09-01

    Congenital factor VII (FVII) deficiency is characterized by genotypic variability and phenotypic heterogeneity. Traditional screening and factor assays are unable to reliably predict clinical bleeding phenotype and guide haemorrhage prevention strategy. Global assays of coagulation and fibrinolysis may better characterize overall haemostatic balance and aid in haemorrhagic risk assessment. We evaluated the ability of novel global assays to better understand clinical bleeding severity in congenital FVII deficiency. Subjects underwent central determination of factor VII activity (FVII:C) as well as clot formation and lysis (CloFAL) and simultaneous thrombin and plasmin generation (STP) global assay analysis. A bleeding score was assigned to each subject through medical chart review. Global assay parameters were analysed with respect to bleeding score and FVII:C. Subgroup analyses were performed on paediatric subjects and subjects with FVII ≥ 1 IU dL(-1). CloFAL fibrinolytic index (FI2 ) inversely correlated with FVII:C while CloFAL maximum amplitude (MA) and STP maximum velocity of thrombin generation (VT max) varied directly with FVII:C. CloFAL FI2 directly correlated with bleeding score among subjects in both the total cohort and paediatric subcohort, but not among subjects with FVII ≥ 1 IU dL(-1) . Among subjects with FVII ≥ 1 IU dL(-1), STP time to maximum velocity of thrombin generation and time to maximum velocity of plasmin generation inversely correlated with bleeding score. These preliminary findings suggest a novel potential link between a hyperfibrinolytic state in bleeding severity and congenital FVII deficiency, an observation that should be further explored. © 2013 John Wiley & Sons Ltd.

  18. Psychosocial and demographic correlates of employment vs disability status in a national community sample of adults with chronic pain: toward a psychology of pain presenteeism.

    PubMed

    Karoly, Paul; Ruehlman, Linda S; Okun, Morris A

    2013-11-01

    Although chronic pain is a source of work-related disability, relatively little research has addressed the psychological factors that differentiate individuals in chronic pain who leave the workforce from those who remain on the job despite their pain. The present study examined a small set of attitudinal and coping-related factors as potential correlates of pain-related disability vs continued part- or full-time employment over and above the role of well-known risk factors. A large sample of adult men and women with chronic pain drawn from across the United States (N = 1,293) by means of random digit dialing was subdivided into two groups: working (N = 859) and on disability (N = 434). Both groups were interviewed (by telephone) to complete a set of instruments (called the Profile of Chronic Pain: Extended Assessment battery) measuring pain attitudes and coping methods. Logistic regression analysis revealed that continued employment status was inversely related to pain severity and was positively related to higher education and being Hispanic. After controlling for severity and demographic factors, belief in a medical cure and catastrophizing tendencies were significant inverse predictors, and task persistence was a positive predictor of continued employment. Results revealed both demographic and attitudinal predictors of continued employment and highlight the value of harnessing insights from the psychology of work engagement to better understand the processes underlying pain presenteeism. Interventions designed to keep persons with pain in the active work force should build upon and extend the present findings. Wiley Periodicals, Inc.

  19. Educational status and cardiovascular risk profile in Indians

    PubMed Central

    Reddy, K. Srinath; Prabhakaran, Dorairaj; Jeemon, Panniyammakal; Thankappan, K. R.; Joshi, Prashant; Chaturvedi, Vivek; Ramakrishnan, Lakshmy; Ahmed, Farooque

    2007-01-01

    The inverse graded relationship of education and risk factors of coronary heart disease (CHD) has been reported from Western populations. To examine whether risk factors of CHD are predicted by level of education and influenced by the level of urbanization in Indian industrial populations, a cross-sectional survey (n = 19,973; response rate, 87.6%) was carried out among employees and their family members in 10 medium-to-large industries in highly urban, urban, and periurban regions of India. Information on behavioral, clinical, and biochemical risk factors of CHD was obtained through standardized instruments, and educational status was assessed in terms of the highest educational level attained. Data from 19,969 individuals were used for analysis. Tobacco use and hypertension were significantly more prevalent in the low- (56.6% and 33.8%, respectively) compared with the high-education group (12.5% and 22.7%, respectively; P < 0.001). However, dyslipidemia prevalence was significantly higher in the high-education group (27.1% as compared with 16.9% in the lowest-education group; P < 0.01). When stratified by the level of urbanization, industrial populations located in highly urbanized centers were observed to have an inverse graded relationship (i.e., higher-education groups had lower prevalence) for tobacco use, hypertension, diabetes, and overweight, whereas in less-urbanized locations, we found such a relationship only for tobacco use and hypertension. This study indicates the growing vulnerability of lower socioeconomic groups to CHD. Preventive strategies to reduce major CHD risk factors should focus on effectively addressing these social disparities. PMID:17923677

  20. Association of birth order with cardiovascular disease risk factors in young adulthood: a study of one million Swedish men.

    PubMed

    Jelenkovic, Aline; Silventoinen, Karri; Tynelius, Per; Myrskylä, Mikko; Rasmussen, Finn

    2013-01-01

    Birth order has been suggested to be linked to several cardiovascular disease (CVD) risk factors, but the evidence is still inconsistent. We aim to determine the associations of birth order with body mass index (BMI), muscle strength and blood pressure. Further we will analyse whether these relationships are affected by family characteristics. BMI, elbow flexion, hand grip and knee extension strength and systolic and diastolic blood pressure were measured at conscription examination in 1,065,710 Swedish young men born between 1951 and 1975. The data were analysed using linear multivariate and fixed effects regression models; the latter compare siblings and account for genetic and social factors shared by brothers. Fixed effect regression analysis showed that birth order was inversely associated with BMI: second and third born had 0.8% and 1.1% (p<0.001) lower BMI than first-born, respectively. The association pattern differed among muscle strengths. After adjustment for BMI, first-born presented lower elbow flexion and hand grip strength than second-born (-5.9 N and -3.8 N, respectively, p<0.001). Knee extension strength was inversely related to birth order though not always significantly. The association between birth order and blood pressure was not significant. Birth order is negatively associated with BMI and knee extension strength, positively with elbow flexion and hand grip strength, and is not associated with blood pressure among young men. Although the effects are small, the link between birth order and some CVD risk factors is already detectable in young adulthood.

  1. Analysis of Tube Hydroforming by means of an Inverse Approach

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nguyen, Ba Nghiep; Johnson, Kenneth I.; Khaleel, Mohammad A.

    2003-05-01

    This paper presents a computational tool for the analysis of freely hydroformed tubes by means of an inverse approach. The formulation of the inverse method developed by Guo et al. is adopted and extended to the tube hydrofoming problems in which the initial geometry is a round tube submitted to hydraulic pressure and axial feed at the tube ends (end-feed). A simple criterion based on a forming limit diagram is used to predict the necking regions in the deformed workpiece. Although the developed computational tool is a stand-alone code, it has been linked to the Marc finite element code formore » meshing and visualization of results. The application of the inverse approach to tube hydroforming is illustrated through the analyses of the aluminum alloy AA6061-T4 seamless tubes under free hydroforming conditions. The results obtained are in good agreement with those issued from a direct incremental approach. However, the computational time in the inverse procedure is much less than that in the incremental method.« less

  2. High-resolution inversion of OMI formaldehyde columns over the Southeast US to infer isoprene emissions

    NASA Astrophysics Data System (ADS)

    Kaiser, J.; Zhu, L.; Travis, K.; Jacob, D.

    2017-12-01

    In the South East United States, biogenic isoprene fuels tropospheric ozone formation, and its oxidation products contribute significantly to organic aerosol. Bottom-up emission inventories rely on very limited isoprene emission and land-cover data, yielding uncertainties of a factor of 2 or more. Here, we use formaldehyde columns from the Ozone Monitoring Instrument in a high-resolution (0.25 x 0.325o) adjoint-based inversion to constrain isoprene emissions over the SE US during Aug-Sept of 2013. We find that the MEGANv2.1 inventory is biased high over most of the SE US. Our derived scaling factors show significant spatial variability, with the largest corrections applied to Louisiana and the Edwards Plateau in Texas. We test our inversion results against a comprehensive set of isoprene oxidation product observations from the NASA SEAC4RS flight campaign. The SEAC4RS data provides new confidence in the satellite retrievals and in mechanism linking isoprene oxidation to formaldehyde production. Finally, we relate the posterior scaling factors to the underlying land-type, and examine potential sources of observed biases.

  3. Association between Socioeconomic Status and Major Risk Factors of Stroke: Thai Epidemiologic Stroke (TES) Study.

    PubMed

    Pipatvanichgul, Boonchai; Hanchaiphiboolkul, Suchat; Puthkhao, Pimchanok; Tantirittisak, Tasanee; Towanabut, Somchai

    2015-08-01

    To investigate the association of socioeconomic status (SES) (education, personal income, and occupation) with four major risk factors of stroke, those are diabetes, hypertension, hypercholesterolemia, and current smoker The Thai Epidemiologic Stroke Study is a community-based cohort study, which recruitedparticipants from the general population from five geographic regions around the country. Cross-sectional baseline data of 19,997 (6,803 men and 13,194 women) participants, aged 45 to 80 years were included in the present analysis. Multiple logistic regression analysis was used to estimate association ofsocioeconomic indicators with the major risk factors of stroke. SES was associated with a major risk factor of stroke. Among three indicators ofsocioeconomic status, education was more consistently associated with the risk factors than personal income and occupation, particularly in women. Education significantly inversely associated with diabetes (p = 0.015 in men and 0.002 in women, respectively), and current smoker in both sexes (p < 0.001), and with hypertension in women (p = 0.011). By contrast, education was significantly positively associated with hypercholesterolemia in women (p < 0.001). The differences in the prevalence of the major risk factors of stroke between SES groups were important, and should be considered in the development ofpolicies or tailored strategies for prevention of stroke.

  4. Eighteen Years of Molecular Genotyping the Hemophilia Inversion Hotspot: From Southern Blot to Inverse Shifting-PCR

    PubMed Central

    Rossetti, Liliana C.; Radic, Claudia P.; Abelleyro, Miguel M.; Larripa, Irene B.; De Brasi, Carlos D.

    2011-01-01

    The factor VIII gene (F8) intron 22 inversion (Inv22) is a paradigmatic duplicon-mediated rearrangement, found in about one half of patients with severe hemophilia A worldwide. The identification of this prevalent cause of hemophilia was delayed for nine years after the F8 characterization in 1984. The aim of this review is to present the wide diversity of practical approaches that have been developed for genotyping the Inv22 (and related int22h rearrangements) since discovery in 1993. The sequence— Southern blot, long distance-PCR and inverse shifting-PCR—for Inv22 genotyping is an interesting example of scientific ingenuity and evolution in order to resolve challenging molecular diagnostic problems. PMID:22072947

  5. Availability Equations for Redundant Systems, Both Single and Multiple Repair Capability

    DTIC Science & Technology

    1987-10-01

    roots of S2StAg)X AL 2 Having the denominator factored enables- Partial fraction expansion and hence finding the inverse transform . The Inverse ...S1 : Xl Tp S2 = x2 ŗ S3 x T The inverse transform for P0 is: Pot l = 6X3 x Sit Spt S t Vs S-)(S2S ’-SS(SS-S )e + iS 3 Si-S 3( e. _S(S 1 -S,)e...roots of S3 + S2 (6\\+6ý0+SMll(\\+2 )+6(1.+-03 S1 -(\\ + • S 2 : -2(X) + • S3 -3(X +0) "The Inverse transform is the same as for Case 3 except for the

  6. Are Cardiovascular Risk Factors also Associated with the Incidence of Atrial Fibrillation?

    PubMed Central

    Allan, Victoria; Honarbakhsh, Shohreh; Casas, Juan-Pablo; Wallace, Joshua; Hunter, Ross; Schilling, Richard; Perel, Pablo; Morley, Katherine; Banerjee, Amitava

    2017-01-01

    Summary Established primary prevention strategies of cardiovascular diseases are based on understanding of risk factors, but whether the same risk factors are associated with atrial fibrillation (AF) remains unclear. We conducted a systematic review and field synopsis of the associations of 23 cardiovascular risk factors and incident AF, which included 84 reports based on 28 consented and four electronic health record cohorts of 20,420,175 participants and 576,602 AF events. We identified 3-19 reports per risk factor and heterogeneity in AF definition, quality of reporting, and adjustment. We extracted relative risks (RR) and 95 % confidence intervals [CI] and visualised the number of reports with inverse (RR [CI]<1.00), or direct (RR [CI]>1.00) associations. For hypertension (13/17 reports) and obesity (19/19 reports), there were direct associations with incident AF, as there are for coronary heart disease (CHD). There were inverse associations for non-White ethnicity (5/5 reports, with RR from 0.35 to 0.84 [0.82–0.85]), total cholesterol (4/13 reports from 0.76 [0.59–0.98] to 0.94 [0.90–0.97]; 8/13 reports with non-significant inverse associations), and diastolic blood pressure (2/11 reports from 0.87 [0.78–0.96] to 0.92 [0.85–0.99]; 5/11 reports with non-significant inverse associations), and direct associations for taller height (7/10 reports from 1.03 [1.02–1.05] to 1.92 [1.38–2.67]), which are in the opposite direction of known associations with CHD. A systematic evaluation of the available evidence suggests similarities as well as important differences in the risk factors for incidence of AF as compared with other cardiovascular diseases, which has implications for the primary prevention strategies for atrial fibrillation. PMID:28229164

  7. The Interaction Between Genetic Ancestry and Breast Cancer Risk Factors among Hispanic women: The Breast Cancer Health Disparities Study

    PubMed Central

    Hines, Lisa M.; Sedjo, Rebecca L.; Byers, Tim; John, Esther M.; Fejerman, Laura; Stern, Mariana C.; Baumgartner, Kathy B.; Giuliano, Anna R.; Torres-Mejia, Gabriela; Wolff, Roger K.; Harrall, Kylie K.; Slattery, Martha L.

    2016-01-01

    Background Hispanic women have lower breast cancer incidence rates than non-Hispanic white (NHW) women. To what extent genetic versus non-genetic factors account for this difference is unknown. Methods Using logistic regression, we evaluated the interactive influences of established risk factors and ethnicity (self-identified and identified by ancestral informative markers) on breast cancer risk among 2326 Hispanic and 1854 NHW postmenopausal women from the US and Mexico in the Breast Cancer Health Disparities Study. Results The inverse association between % Native American(NA) ancestry and breast cancer risk was only slightly attenuated after adjusting for known risk factors [lowest versus highest quartile: odds ratio(OR)=1.39, 95% confidence interval(CI)=1.00–1.92 among US Hispanics; OR=1.92 (1.29–2.86) among Mexican women]. The prevalence of several risk factors, as well as the associations with certain factors and breast cancer risk, differed according to genetic admixture. For example, higher BMI was associated with reduced risk among women with lower NA ancestry only [BMI <25 versus >30: OR=0.65 (0.44–0.98) among US Hispanics; OR=0.53 (0.29–0.97) among Mexicans]. The average number of risk factors among cases was inversely related to % NA ancestry. Conclusions The lower NA ancestry groups were more likely to have the established risk factors, with the exception of BMI. While the majority of factors were associated with risk in the expected directions among all women, BMI had an inverse association among Hispanics with lower NA ancestry. Impact These data suggest that the established risk factors are less relevant for breast cancer development among women with more NA ancestry. PMID:27932594

  8. First-Order Parametric Model of Reflectance Spectra for Dyed Fabrics

    DTIC Science & Technology

    2016-02-19

    Unclassified Unlimited 31 Daniel Aiken (202) 279-5293 Parametric modeling Inverse /direct analysis This report describes a first-order parametric model of...Appendix: Dielectric Response Functions for Dyes Obtained by Inverse Analysis ……………………………...…………………………………………………….19 1 First-Order Parametric...which provides for both their inverse and direct modeling1. The dyes considered contain spectral features that are of interest to the U.S. Navy for

  9. A Common 16p11.2 Inversion Underlies the Joint Susceptibility to Asthma and Obesity

    PubMed Central

    González, Juan R.; Cáceres, Alejandro; Esko, Tonu; Cuscó, Ivon; Puig, Marta; Esnaola, Mikel; Reina, Judith; Siroux, Valerie; Bouzigon, Emmanuelle; Nadif, Rachel; Reinmaa, Eva; Milani, Lili; Bustamante, Mariona; Jarvis, Deborah; Antó, Josep M.; Sunyer, Jordi; Demenais, Florence; Kogevinas, Manolis; Metspalu, Andres; Cáceres, Mario; Pérez-Jurado, Luis A.

    2014-01-01

    The prevalence of asthma and obesity is increasing worldwide, and obesity is a well-documented risk factor for asthma. The mechanisms underlying this association and parallel time trends remain largely unknown but genetic factors may be involved. Here, we report on a common ∼0.45 Mb genomic inversion at 16p11.2 that can be accurately genotyped via SNP array data. We show that the inversion allele protects against the joint occurrence of asthma and obesity in five large independent studies (combined sample size of 317 cases and 543 controls drawn from a total of 5,809 samples; combined OR = 0.48, p = 5.5 × 10−6). Allele frequencies show remarkable worldwide population stratification, ranging from 10% in East Africa to 49% in Northern Europe, consistent with discordant and extreme genetic drifts or adaptive selections after human migration out of Africa. Inversion alleles strongly correlate with expression levels of neighboring genes, especially TUFM (p = 3.0 × 10−40) that encodes a mitochondrial protein regulator of energy balance and inhibitor of type 1 interferon, and other candidates for asthma (IL27) and obesity (APOB48R and SH2B1). Therefore, by affecting gene expression, the ∼0.45 Mb 16p11.2 inversion provides a genetic basis for the joint susceptibility to asthma and obesity, with a population attributable risk of 39.7%. Differential mitochondrial function and basal energy balance of inversion alleles might also underlie the potential selection signature that led to their uneven distribution in world populations. PMID:24560518

  10. Genome-wide association tests of inversions with application to psoriasis

    PubMed Central

    Ma, Jianzhong; Xiong, Momiao; You, Ming; Lozano, Guillermina; Amos, Christopher I.

    2014-01-01

    Although inversions have occasionally been found to be associated with disease susceptibility through interrupting a gene or its regulatory region, or by increasing the risk for deleterious secondary rearrangements, no association study has been specifically conducted for risks associated with inversions, mainly because existing approaches to detecting and genotyping inversions do not readily scale to a large number of samples. Based on our recently proposed approach to identifying and genotyping inversions using principal components analysis (PCA), we herein develop a method of detecting association between inversions and disease in a genome-wide fashion. Our method uses genotype data for single nucleotide polymorphisms (SNPs), and is thus cost-efficient and computationally fast. For an inversion polymorphism, local PCA around the inversion region is performed to infer the inversion genotypes of all samples. For many inversions, we found that some of the SNPs inside an inversion region are fixed in the two lineages of different orientations and thus can serve as surrogate markers. Our method can be applied to case-control and quantitative trait association studies to identify inversions that may interrupt a gene or the connection between a gene and its regulatory agents. Our method also offers a new venue to identify inversions that are responsible for disease-causing secondary rearrangements. We illustrated our proposed approach to case-control data for psoriasis and identified novel associations with a few inversion polymorphisms. PMID:24623382

  11. Roles of predation, food, and temperature in structuring the epilimnetic zooplankton populations in Lake Ontario, 1981-1986

    USGS Publications Warehouse

    Johannsson, Ora E.; O'Gorman, Robert

    1991-01-01

    We sampled phytoplankton, zooplankton, and alewives Alosa pseudoharengus and measured water temperature in Lake Ontario during 1981–1986. Through the use of general linear regression models we then sought evidence of control of the eplimnetic zooplankton community (mid-July to mid-October) by producers, consumers, and temperature. Our measures of the zooplankton community were total biomass, cladoceran biomass, and the ratio of large to small Daphnia spp. (D. galeata mendotae andD. retrocurva). Zooplankton population variables assessed were abundance, egg ratio, and productivity. Through factor analysis, factors were created from the standardized, transformed independent variables for use in the regression analyses. Regression models showed significant inverse relationships (P < 0.05) between alewives and Bosmina longirostris (abundance, production, and egg ratio), Ceriodaphnia lacustris (egg ratio), andDaphnia retrocurva (egg ratio). Bosmina longirostris and D. retrocurva egg ratios were inversely related to algae biomass (<20 μm), thus the smaller algae might be controlled in part by the zooplankton community. Production of C. lacustris was directly related to temperature, as was the production and abundance of Tropocyclops prasinus. The annual size-frequency distributions of B. longirostris and D. retrocurva were inversely related to yearling alewife abundance and directly related to adult alewife abundance, which suggested that yearlings use a particulate-feeding mode on these zooplankton species more frequently than adults. We found no significant negative correlations among the zooplankton species, which suggested that interzooplankton predation and competition were not as important in structuring the community as were planktivory and temperature.

  12. A review on the systematic formulation of 3-D multiparameter full waveform inversion in viscoelastic medium

    NASA Astrophysics Data System (ADS)

    Yang, Pengliang; Brossier, Romain; Métivier, Ludovic; Virieux, Jean

    2016-10-01

    In this paper, we study 3-D multiparameter full waveform inversion (FWI) in viscoelastic media based on the generalized Maxwell/Zener body including arbitrary number of attenuation mechanisms. We present a frequency-domain energy analysis to establish the stability condition of a full anisotropic viscoelastic system, according to zero-valued boundary condition and the elastic-viscoelastic correspondence principle: the real-valued stiffness matrix becomes a complex-valued one in Fourier domain when seismic attenuation is taken into account. We develop a least-squares optimization approach to linearly relate the quality factor with the anelastic coefficients by estimating a set of constants which are independent of the spatial coordinates, which supplies an explicit incorporation of the parameter Q in the general viscoelastic wave equation. By introducing the Lagrangian multipliers into the matrix expression of the wave equation with implicit time integration, we build a systematic formulation of multiparameter FWI for full anisotropic viscoelastic wave equation, while the equivalent form of the state and adjoint equation with explicit time integration is available to be resolved efficiently. In particular, this formulation lays the foundation for the inversion of the parameter Q in the time domain with full anisotropic viscoelastic properties. In the 3-D isotropic viscoelastic settings, the anelastic coefficients and the quality factors using bulk and shear moduli parametrization can be related to the counterparts using P and S velocity. Gradients with respect to any other parameter of interest can be found by chain rule. Pioneering numerical validations as well as the real applications of this most generic framework will be carried out to disclose the potential of viscoelastic FWI when adequate high-performance computing resources and the field data are available.

  13. Inverse Association between Hepatitis B Virus Infection and Fatty Liver Disease: A Large-Scale Study in Populations Seeking for Check-Up

    PubMed Central

    Cheng, Yuan-Lung; Wang, Yuan-Jen; Kao, Wei-Yu; Chen, Ping-Hsien; Huo, Teh-Ia; Huang, Yi-Hsiang; Lan, Keng-Hsin; Su, Chien-Wei; Chan, Wan-Leong; Lin, Han-Chieh; Lee, Fa-Yauh; Wu, Jaw-Ching

    2013-01-01

    Background Although many studies have attempted to clarify the association between hepatitis B virus (HBV) infection and fatty liver disease, no prior studies have emphasized the relationship of HBV and fatty liver regarding different demographics of age and body mass index (BMI). Aim To investigate the correlation of HBV and fatty liver in the different demographics of age and BMI. Methods We enrolled consecutive subjects who had received health check-up services at the Taipei Veterans General Hospital from 2002 to 2009 and ultrasonography was used to diagnose fatty liver according to the practice guidelines of the American Gastroenterological Association. Results Among the 33,439 subjects enrolled in this study, fatty liver was diagnosed in 43.9% of the population and 38.9% of patients with chronic HBV infection. Multivariate analysis showed that BMI, age, waist circumference, systolic blood pressure, fasting glucose, cholesterol, alanine aminotransferase (ALT) levels, and platelet counts were positively associated, while hepatitis B surface antigen (HBsAg) positivity was inversely associated with fatty liver, especially for subjects with BMI>22.4 kg/m2 and age>50 years. On the contrary, HBV infection was positively correlated with the presence of elevated serum ALT levels in subjects with fatty liver disease regardless of their age and BMI. Conclusions Metabolic factors are important determinants for the prevalence of fatty liver. Patients with HBV infection were inversely associated with fatty liver disease than the general population, especially in older and obese patients. Furthermore, metabolic factors and HBV infection were associated with elevated serum ALT levels in fatty liver disease. PMID:23991037

  14. Relationships between serum leptin levels and bone mineral parameters in school-aged children: a 3-year follow-up study.

    PubMed

    Kouda, Katsuyasu; Ohara, Kumiko; Fujita, Yuki; Nakamura, Harunobu; Tachiki, Takahiro; Iki, Masayuki

    2018-02-02

    Leptin regulates bone cell differentiation and functions via direct and indirect actions in experimental settings. Epidemiologically, however, the impact of leptin on the regulation of bone metabolism remains unclear. While some studies have reported a positive relationship between leptin and bone mineral parameters, other studies found an inverse or no association. We analyzed data from a population-based follow-up survey of community-dwelling children in Hamamatsu, Japan, to investigate relationships between leptin levels and bone mineral parameters. Multiple regression analysis was performed. Multicollinearity was quantified using the variance infiltration factor (VIF). Among 408 children who participated in the baseline survey (at age 11.2 years), 254 (121 boys and 133 girls) completed the follow-up survey (at age 14.2 years). Leptin levels were strongly related to fat mass (r = 0.87 in boys, r = 0.80 in girls). Leptin levels at baseline were significantly (P < 0.05) positively related to total body less head (TBLH) areal bone mineral density (aBMD) at follow-up in girls (standardized partial regression coefficient: β = 0.302, VIF = 2.246), after adjusting for body fat percentage (%). On the other hand, leptin levels were inversely related to TBLH aBMD in boys (β = - 0.395, VIF = 4.116), after adjusting for body fat mass (kg). Positive relationships between leptin levels and bone mineral parameters were observed with VIF values < 4.0, whereas inverse relationships were observed with VIF values ≥ 4.0. These findings suggest that positive relationships between leptin levels and bone mineral parameters are weak, or not always observed, due to statistical problems (i.e., multicollinearity) and other factors derived from adipose tissue.

  15. Ecological niche partitioning between Anopheles gambiae molecular forms in Cameroon: the ecological side of speciation

    PubMed Central

    Simard, Frédéric; Ayala, Diego; Kamdem, Guy Colince; Pombi, Marco; Etouna, Joachim; Ose, Kenji; Fotsing, Jean-Marie; Fontenille, Didier; Besansky, Nora J; Costantini, Carlo

    2009-01-01

    Background Speciation among members of the Anopheles gambiae complex is thought to be promoted by disruptive selection and ecological divergence acting on sets of adaptation genes protected from recombination by polymorphic paracentric chromosomal inversions. However, shared chromosomal polymorphisms between the M and S molecular forms of An. gambiae and insufficient information about their relationship with ecological divergence challenge this view. We used Geographic Information Systems, Ecological Niche Factor Analysis, and Bayesian multilocus genetic clustering to explore the nature and extent of ecological and chromosomal differentiation of M and S across all the biogeographic domains of Cameroon in Central Africa, in order to understand the role of chromosomal arrangements in ecological specialisation within and among molecular forms. Results Species distribution modelling with presence-only data revealed differences in the ecological niche of both molecular forms and the sibling species, An. arabiensis. The fundamental environmental envelope of the two molecular forms, however, overlapped to a large extent in the rainforest, where they occurred in sympatry. The S form had the greatest niche breadth of all three taxa, whereas An. arabiensis and the M form had the smallest niche overlap. Correspondence analysis of M and S karyotypes confirmed that molecular forms shared similar combinations of chromosomal inversion arrangements in response to the eco-climatic gradient defining the main biogeographic domains occurring across Cameroon. Savanna karyotypes of M and S, however, segregated along the smaller-scale environmental gradient defined by the second ordination axis. Population structure analysis identified three chromosomal clusters, each containing a mixture of M and S specimens. In both M and S, alternative karyotypes were segregating in contrasted environments, in agreement with a strong ecological adaptive value of chromosomal inversions. Conclusion Our data suggest that inversions on the second chromosome of An. gambiae are not causal to the evolution of reproductive isolation between the M and S forms. Rather, they are involved in ecological specialization to a similar extent in both genetic backgrounds, and most probably predated lineage splitting between molecular forms. However, because chromosome-2 inversions promote ecological divergence, resulting in spatial and/or temporal isolation between ecotypes, they might favour mutations in other ecologically significant genes to accumulate in unlinked chromosomal regions. When such mutations occur in portions of the genome where recombination is suppressed, such as the pericentromeric regions known as speciation islands in An. gambiae, they would contribute further to the development of reproductive isolation. PMID:19460146

  16. Usage of multivariate geostatistics in interpolation processes for meteorological precipitation maps

    NASA Astrophysics Data System (ADS)

    Gundogdu, Ismail Bulent

    2017-01-01

    Long-term meteorological data are very important both for the evaluation of meteorological events and for the analysis of their effects on the environment. Prediction maps which are constructed by different interpolation techniques often provide explanatory information. Conventional techniques, such as surface spline fitting, global and local polynomial models, and inverse distance weighting may not be adequate. Multivariate geostatistical methods can be more significant, especially when studying secondary variables, because secondary variables might directly affect the precision of prediction. In this study, the mean annual and mean monthly precipitations from 1984 to 2014 for 268 meteorological stations in Turkey have been used to construct country-wide maps. Besides linear regression, the inverse square distance and ordinary co-Kriging (OCK) have been used and compared to each other. Also elevation, slope, and aspect data for each station have been taken into account as secondary variables, whose use has reduced errors by up to a factor of three. OCK gave the smallest errors (1.002 cm) when aspect was included.

  17. Quantifying Multistate Cytoplasmic Molecular Diffusion in Bacterial Cells via Inverse Transform of Confined Displacement Distribution.

    PubMed

    Chen, Tai-Yen; Jung, Won; Santiago, Ace George; Yang, Feng; Krzemiński, Łukasz; Chen, Peng

    2015-11-12

    Single-molecule tracking (SMT) of fluorescently tagged cytoplasmic proteins can provide valuable information on the underlying biological processes in living cells via subsequent analysis of the displacement distributions; however, the confinement effect originated from the small size of a bacterial cell skews the protein's displacement distribution and complicates the quantification of the intrinsic diffusive behaviors. Using the inverse transformation method, we convert the skewed displacement distribution (for both 2D and 3D imaging conditions) back to that in free space for systems containing one or multiple (non)interconverting Brownian diffusion states, from which we can reliably extract the number of diffusion states as well as their intrinsic diffusion coefficients and respective fractional populations. We further demonstrate a successful application to experimental SMT data of a transcription factor in living E. coli cells. This work allows a direct quantitative connection between cytoplasmic SMT data with diffusion theory for analyzing molecular diffusive behavior in live bacteria.

  18. Quantifying Multistate Cytoplasmic Molecular Diffusion in Bacterial Cells via Inverse Transform of Confined Displacement Distribution

    PubMed Central

    2016-01-01

    Single-molecule tracking (SMT) of fluorescently tagged cytoplasmic proteins can provide valuable information on the underlying biological processes in living cells via subsequent analysis of the displacement distributions; however, the confinement effect originated from the small size of a bacterial cell skews the protein’s displacement distribution and complicates the quantification of the intrinsic diffusive behaviors. Using the inverse transformation method, we convert the skewed displacement distribution (for both 2D and 3D imaging conditions) back to that in free space for systems containing one or multiple (non)interconverting Brownian diffusion states, from which we can reliably extract the number of diffusion states as well as their intrinsic diffusion coefficients and respective fractional populations. We further demonstrate a successful application to experimental SMT data of a transcription factor in living E. coli cells. This work allows a direct quantitative connection between cytoplasmic SMT data with diffusion theory for analyzing molecular diffusive behavior in live bacteria. PMID:26491971

  19. A study of factors affecting properties of AM/AMPS/NVP terpolymeric microspheres prepared by inverse suspension polymerization

    NASA Astrophysics Data System (ADS)

    Jiang, J. F.; Zhao, Q.; Lin, M. Q.; Wang, Y. F.; Dang, S. M.; Sun, F. F.

    2015-12-01

    Terpolymeric microspheres were synthesized by the inverse suspension polymerization of functional monomers including AMPS, NVP, and AM. The morphology and size of the obtained microspheres were measured by scanning electron microscopy (SEM) and optical microscopy. Furthermore, the swelling performances of the obtained microspheres were measured with alaser particle analyzer (LPA), and the thermal stability of the microspheres obtained was measured by differential thermal analysis (DSC-TG) and high temperature experiments involving microsphere/water dispersion. The results revealed that the extreme value of the microsphere size distribution decreased from 280 μm to 20 μm as the stirring rate increased from 175 rpm to 500 rpm. At temperatures below 25°C, the maximum achieved swelling ratio of the microspheres was 21, and the thermal stability of the terpolymer microspheres was significantly higher than that of the dipolymer microspheres. The terpolymer/water dispersions were kept at 120°C for 19d before any damage was observed.

  20. Technical Note: Atmospheric CO2 inversions on the mesoscale using data-driven prior uncertainties: methodology and system evaluation

    NASA Astrophysics Data System (ADS)

    Kountouris, Panagiotis; Gerbig, Christoph; Rödenbeck, Christian; Karstens, Ute; Koch, Thomas Frank; Heimann, Martin

    2018-03-01

    Atmospheric inversions are widely used in the optimization of surface carbon fluxes on a regional scale using information from atmospheric CO2 dry mole fractions. In many studies the prior flux uncertainty applied to the inversion schemes does not directly reflect the true flux uncertainties but is used to regularize the inverse problem. Here, we aim to implement an inversion scheme using the Jena inversion system and applying a prior flux error structure derived from a model-data residual analysis using high spatial and temporal resolution over a full year period in the European domain. We analyzed the performance of the inversion system with a synthetic experiment, in which the flux constraint is derived following the same residual analysis but applied to the model-model mismatch. The synthetic study showed a quite good agreement between posterior and true fluxes on European, country, annual and monthly scales. Posterior monthly and country-aggregated fluxes improved their correlation coefficient with the known truth by 7 % compared to the prior estimates when compared to the reference, with a mean correlation of 0.92. The ratio of the SD between the posterior and reference and between the prior and reference was also reduced by 33 % with a mean value of 1.15. We identified temporal and spatial scales on which the inversion system maximizes the derived information; monthly temporal scales at around 200 km spatial resolution seem to maximize the information gain.

  1. Numerical Representation of Wintertime Near-Surface Inversions in the Arctic with a 2.5-km Version of the Global Environmental Multiscale (GEM) Model

    NASA Astrophysics Data System (ADS)

    Dehghan, A.; Mariani, Z.; Gascon, G.; Bélair, S.; Milbrandt, J.; Joe, P. I.; Crawford, R.; Melo, S.

    2017-12-01

    Environment and Climate Change Canada (ECCC) is implementing a 2.5-km resolution version of the Global Environmental Multiscale (GEM) model over the Canadian Arctic. Radiosonde observations were used to evaluate the numerical representation of surface-based temperature inversion which is a major feature in the Arctic region. Arctic surface-based inversions are often created by imbalance between radiative cooling processes at surface and warm air advection above. This can have a significant effect on vertical mixing of pollutants and moisture, and ultimately, on cloud formation. It is therefore important to correctly predict the existence of surface inversions along with their characteristics (i.e., intensity and depth). Previous climatological studies showed that the frequency and intensity of surface-based inversions are larger during colder months in the Arctic. Therefore, surface-based inversions were estimated using radiosonde measurements during winter (December 2015 to February 2016) at Iqaluit (Nunavut, Canada). Results show that the inversion intensity can exceed 10 K with depths as large as 1 km. Preliminary evaluation of GEM outputs reveals that the model tends to underestimate the intensity of near-surface inversions, and in some cases, the model failed to predict an inversion. This study presents the factors contributing to this bias including surface temperature and snow cover.

  2. Perceived stress, insomnia and related factors in women around the menopause.

    PubMed

    Cuadros, José L; Fernández-Alonso, Ana M; Cuadros-Celorrio, Angela M; Fernández-Luzón, Nuria; Guadix-Peinado, María J; del Cid-Martín, Nadia; Chedraui, Peter; Pérez-López, Faustino R

    2012-08-01

    Studies assessing perceived stress and insomnia in mid-aged women are scarce. To assess perceived stress, insomnia and related factors in mid-aged Spanish women. This was a cross sectional study in which 235 women aged 40-65 completed the Menopause Rating Scale (MRS), the Perceived Stress Scale (PSS), the Insomnia Severity Index (ISI), and a general socio-demographic questionnaire containing personal and partner data. Internal consistency of each tool was also computed. Median [interquartile range] age of the sample was 52 [9.0] years. A 61.3% were postmenopausal, 49.4% had increased body mass index values, 43.8% were abdominally obese, 11.9% had hypertension, and 74.0% had a partner. In addition, 9.8% used hormone therapy and 12.3% psychotropic drugs. Multiple linear regression analysis found that higher PSS scores (more stress) inversely correlated with female age and positively with MRS psychological and urogenital scores (impaired quality of life in these domains), total higher ISI scores (more insomnia) and partner premature ejaculation. Higher ISI scores positively correlated with PSS and MRS somatic scores and partner unfaithfulness, and inversely with female hip circumference. In this mid-aged Spanish sample perceived stress and insomnia were significantly correlated and related to various female and partner issues. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  3. Design optimization of axial flow hydraulic turbine runner: Part II - multi-objective constrained optimization method

    NASA Astrophysics Data System (ADS)

    Peng, Guoyi; Cao, Shuliang; Ishizuka, Masaru; Hayama, Shinji

    2002-06-01

    This paper is concerned with the design optimization of axial flow hydraulic turbine runner blade geometry. In order to obtain a better design plan with good performance, a new comprehensive performance optimization procedure has been presented by combining a multi-variable multi-objective constrained optimization model with a Q3D inverse computation and a performance prediction procedure. With careful analysis of the inverse design of axial hydraulic turbine runner, the total hydraulic loss and the cavitation coefficient are taken as optimization objectives and a comprehensive objective function is defined using the weight factors. Parameters of a newly proposed blade bound circulation distribution function and parameters describing positions of blade leading and training edges in the meridional flow passage are taken as optimization variables.The optimization procedure has been applied to the design optimization of a Kaplan runner with specific speed of 440 kW. Numerical results show that the performance of designed runner is successfully improved through optimization computation. The optimization model is found to be validated and it has the feature of good convergence. With the multi-objective optimization model, it is possible to control the performance of designed runner by adjusting the value of weight factors defining the comprehensive objective function. Copyright

  4. Different meteorological parameters influence metapneumovirus and respiratory syncytial virus activity.

    PubMed

    Darniot, Magali; Pitoiset, Cécile; Millière, Laurine; Aho-Glélé, Ludwig Serge; Florentin, Emmanuel; Bour, Jean-Baptiste; Manoha, Catherine

    2018-05-05

    Both human metapneumovirus (hMPV) and respiratory syncytial virus (RSV) cause epidemics during the cold season in temperate climates. The purpose of this study was to find out whether climatic factors are associated with RSV and hMPV epidemics. Our study was based on data from 4300 patients admitted to the Dijon University Hospital for acute respiratory infection (ARI) over three winter seasons chosen for their dissimilar meteorological and virological patterns. Cases of hMPV and RSV were correlated with meteorological parameters recorded in the Dijon area. The relationship between virus data and local meteorological conditions was analyzed by univariate and multivariate negative binomial regression analysis. RSV detection was inversely associated with temperature and positively with relative humidity and air pressure, whereas hMPV was inversely associated with temperature and positively with wind speed. The association among meteorological variables and weekly ARIs cases due to RSV and hMPV demonstrated the relevance of climate factors as contributors to both hMPV and RSV activities. Meteorological drivers of RSV and hMPV epidemics are different. Low temperatures influence both hMPV and RSV activity. Relative humidity is an important predictor of RSV activity, but it does not influence hMPV activity. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sirunyan, Albert M; et al.

    The transverse momentum (pt) spectrum of prompt D0 mesons and their antiparticles has been measured via the hadronic decay channels D0 to K- pi+ and D0-bar to K+ pi- in pp and PbPb collisions at a centre-of-mass energy of 5.02 TeV per nucleon pair with the CMS detector at the LHC. The measurement is performed in the D0 meson pt range of 2-100 GeV and in the rapidity range of abs(y)<1. The pp (PbPb) dataset used for this analysis corresponds to an integrated luminosity of 27.4 inverse picobarns (530 inverse microbarns). The measured D0 meson pt spectrum in pp collisionsmore » is well described by perturbative QCD calculations. The nuclear modification factor, comparing D0 meson yields in PbPb and pp collisions, was extracted for both minimum-bias and the 10% most central PbPb interactions. For central events, the D0 meson yield in the PbPb collisions is suppressed by a factor of 5-6 compared to the pp reference in the pt range of 6-10 GeV. For D0 mesons in the high-pt range of 60-100 GeV, a significantly smaller suppression is observed. The results are also compared to theoretical calculations.« less

  6. Diffusion and decay chain of radioisotopes in stagnant water in saturated porous media.

    PubMed

    Guzmán, Juan; Alvarez-Ramirez, Jose; Escarela-Pérez, Rafael; Vargas, Raúl Alejandro

    2014-09-01

    The analysis of the diffusion of radioisotopes in stagnant water in saturated porous media is important to validate the performance of barrier systems used in radioactive repositories. In this work a methodology is developed to determine the radioisotope concentration in a two-reservoir configuration: a saturated porous medium with stagnant water is surrounded by two reservoirs. The concentrations are obtained for all the radioisotopes of the decay chain using the concept of overvalued concentration. A methodology, based on the variable separation method, is proposed for the solution of the transport equation. The novelty of the proposed methodology involves the factorization of the overvalued concentration in two factors: one that describes the diffusion without decay and another one that describes the decay without diffusion. It is possible with the proposed methodology to determine the required time to obtain equal injective and diffusive concentrations in reservoirs. In fact, this time is inversely proportional to the diffusion coefficient. In addition, the proposed methodology allows finding the required time to get a linear and constant space distribution of the concentration in porous mediums. This time is inversely proportional to the diffusion coefficient. In order to validate the proposed methodology, the distributions in the radioisotope concentrations are compared with other experimental and numerical works. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. SaaS Platform for Time Series Data Handling

    NASA Astrophysics Data System (ADS)

    Oplachko, Ekaterina; Rykunov, Stanislav; Ustinin, Mikhail

    2018-02-01

    The paper is devoted to the description of MathBrain, a cloud-based resource, which works as a "Software as a Service" model. It is designed to maximize the efficiency of the current technology and to provide a tool for time series data handling. The resource provides access to the following analysis methods: direct and inverse Fourier transforms, Principal component analysis and Independent component analysis decompositions, quantitative analysis, magnetoencephalography inverse problem solution in a single dipole model based on multichannel spectral data.

  8. OCT structure, COB location and magmatic type of the S Angolan & SE Brazilian margins from integrated quantitative analysis of deep seismic reflection and gravity anomaly data

    NASA Astrophysics Data System (ADS)

    Cowie, Leanne; Kusznir, Nick; Horn, Brian

    2014-05-01

    Integrated quantitative analysis using deep seismic reflection data and gravity inversion have been applied to the S Angolan and SE Brazilian margins to determine OCT structure, COB location and magmatic type. Knowledge of these margin parameters are of critical importance for understanding rifted continental margin formation processes and in evaluating petroleum systems in deep-water frontier oil and gas exploration. The OCT structure, COB location and magmatic type of the S Angolan and SE Brazilian rifted continental margins are much debated; exhumed and serpentinised mantle have been reported at these margins. Gravity anomaly inversion, incorporating a lithosphere thermal gravity anomaly correction, has been used to determine Moho depth, crustal basement thickness and continental lithosphere thinning. Residual Depth Anomaly (RDA) analysis has been used to investigate OCT bathymetric anomalies with respect to expected oceanic bathymetries and subsidence analysis has been used to determine the distribution of continental lithosphere thinning. These techniques have been validated for profiles Lusigal 12 and ISE-01 on the Iberian margin. In addition a joint inversion technique using deep seismic reflection and gravity anomaly data has been applied to the ION-GXT BS1-575 SE Brazil and ION-GXT CS1-2400 S Angola deep seismic reflection lines. The joint inversion method solves for coincident seismic and gravity Moho in the time domain and calculates the lateral variations in crustal basement densities and velocities along the seismic profiles. Gravity inversion, RDA and subsidence analysis along the ION-GXT BS1-575 profile, which crosses the Sao Paulo Plateau and Florianopolis Ridge of the SE Brazilian margin, predict the COB to be located SE of the Florianopolis Ridge. Integrated quantitative analysis shows no evidence for exhumed mantle on this margin profile. The joint inversion technique predicts oceanic crustal thicknesses of between 7 and 8 km thickness with normal oceanic basement seismic velocities and densities. Beneath the Sao Paulo Plateau and Florianopolis Ridge, joint inversion predicts crustal basement thicknesses between 10-15km with high values of basement density and seismic velocities under the Sao Paulo Plateau which are interpreted as indicating a significant magmatic component within the crustal basement. The Sao Paulo Plateau and Florianopolis Ridge are separated by a thin region of crustal basement beneath the salt interpreted as a regional transtensional structure. Sediment corrected RDAs and gravity derived "synthetic" RDAs are of a similar magnitude on oceanic crust, implying negligible mantle dynamic topography. Gravity inversion, RDA and subsidence analysis along the S Angolan ION-GXT CS1-2400 profile suggests that exhumed mantle, corresponding to a magma poor margin, is absent..The thickness of earliest oceanic crust, derived from gravity and deep seismic reflection data, is approximately 7km consistent with the global average oceanic crustal thicknesses. The joint inversion predicts a small difference between oceanic and continental crustal basement density and seismic velocity, with the change in basement density and velocity corresponding to the COB independently determined from RDA and subsidence analysis. The difference between the sediment corrected RDA and that predicted from gravity inversion crustal thickness variation implies that this margin is experiencing approximately 500m of anomalous uplift attributed to mantle dynamic uplift.

  9. Mantle viscosity structure constrained by joint inversions of seismic velocities and density

    NASA Astrophysics Data System (ADS)

    Rudolph, M. L.; Moulik, P.; Lekic, V.

    2017-12-01

    The viscosity structure of Earth's deep mantle affects the thermal evolution of Earth, the ascent of mantle upwellings, sinking of subducted oceanic lithosphere, and the mixing of compositional heterogeneities in the mantle. Modeling the long-wavelength dynamic geoid allows us to constrain the radial viscosity profile of the mantle. Typically, in inversions for the mantle viscosity structure, wavespeed variations are mapped into density variations using a constant- or depth-dependent scaling factor. Here, we use a newly developed joint model of anisotropic Vs, Vp, density and transition zone topographies to generate a suite of solutions for the mantle viscosity structure directly from the seismologically constrained density structure. The density structure used to drive our forward models includes contributions from both thermal and compositional variations, including important contributions from compositionally dense material in the Large Low Velocity Provinces at the base of the mantle. These compositional variations have been neglected in the forward models used in most previous inversions and have the potential to significantly affect large-scale flow and thus the inferred viscosity structure. We use a transdimensional, hierarchical, Bayesian approach to solve the inverse problem, and our solutions for viscosity structure include an increase in viscosity below the base of the transition zone, in the shallow lower mantle. Using geoid dynamic response functions and an analysis of the correlation between the observed geoid and mantle structure, we demonstrate the underlying reason for this inference. Finally, we present a new family of solutions in which the data uncertainty is accounted for using covariance matrices associated with the mantle structure models.

  10. An Inverse Modeling Approach to Estimating Phytoplankton Pigment Concentrations from Phytoplankton Absorption Spectra

    NASA Technical Reports Server (NTRS)

    Moisan, John R.; Moisan, Tiffany A. H.; Linkswiler, Matthew A.

    2011-01-01

    Phytoplankton absorption spectra and High-Performance Liquid Chromatography (HPLC) pigment observations from the Eastern U.S. and global observations from NASA's SeaBASS archive are used in a linear inverse calculation to extract pigment-specific absorption spectra. Using these pigment-specific absorption spectra to reconstruct the phytoplankton absorption spectra results in high correlations at all visible wavelengths (r(sup 2) from 0.83 to 0.98), and linear regressions (slopes ranging from 0.8 to 1.1). Higher correlations (r(sup 2) from 0.75 to 1.00) are obtained in the visible portion of the spectra when the total phytoplankton absorption spectra are unpackaged by multiplying the entire spectra by a factor that sets the total absorption at 675 nm to that expected from absorption spectra reconstruction using measured pigment concentrations and laboratory-derived pigment-specific absorption spectra. The derived pigment-specific absorption spectra were further used with the total phytoplankton absorption spectra in a second linear inverse calculation to estimate the various phytoplankton HPLC pigments. A comparison between the estimated and measured pigment concentrations for the 18 pigment fields showed good correlations (r(sup 2) greater than 0.5) for 7 pigments and very good correlations (r(sup 2) greater than 0.7) for chlorophyll a and fucoxanthin. Higher correlations result when the analysis is carried out at more local geographic scales. The ability to estimate phytoplankton pigments using pigment-specific absorption spectra is critical for using hyperspectral inverse models to retrieve phytoplankton pigment concentrations and other Inherent Optical Properties (IOPs) from passive remote sensing observations.

  11. Multibeam inverse intensity-modulated radiotherapy (IMRT) for whole breast irradiation: a single center experience in China.

    PubMed

    Yang, Zhaozhi; Zhang, Li; Chen, Xingxing; Ma, Jinli; Mei, Xin; Chen, Jiayi; Yu, Xiaoli; Guo, Xiaomao

    2015-10-27

    To present the clinical experience in our cancer center with multibeam inverse intensity-modulated radiotherapy (IMRT) for early stage breast cancer (BC) patients with whole breast irradiation (WBI). We retrospectively analyzed 622 patients with Stage 0 to III BC treated from 2008 to 2011 with wide local excision and WBI, using an inverse IMRT technique. All of the patients were prescribed a total dose of 50 Gy to the whole breast in 2-Gy fractions, followed by a tumor bed boost of 10 Gy in 5 fractions using an electron beam. Of all of the patients, 132 (21.2%) received whole breast plus regional lymph node (RLN) irradiation. 438 of 622 patients had records of acute skin toxicity based on common terminology criteria (CTC) for adverse events. Two hundred eighty (64%) patients had Grade 0/1 toxicity, 153 (35%) had Grade 2 and only 4 patients experienced grade 3 toxicity. Seventy patients (16%) had moist desquamation. Univariate analysis revealed that breast planning target volume was the only predictive factor for Grade ≥2 acute dermatitis (P = 0.002). After 4 years, 170 patients reported cosmetic results by self-assessment, of whom 151 (89%) patients reported good/excellent cosmetic results, and 17 (11%) patients reported fair assessments. For invasive cancer, the four-year rate of freedom from locoregional recurrence survival was 98.3%. Regarding carcinoma in situ, no patients experienced recurrence. BC patients who underwent conservative surgery followed by inverse IMRT plan exhibited acceptable acute toxicities and clinical outcomes. Longer follow-up is needed.

  12. An evaluation of treatment strategies for head and neck cancer in an African American population.

    PubMed

    Ignacio, D N; Griffin, J J; Daniel, M G; Serlemitsos-Day, M T; Lombardo, F A; Alleyne, T A

    2013-07-01

    This study evaluated treatment strategies for head and neck cancers in a predominantly African American population. Data were collected utilizing medical records and the tumour registry at the Howard University Hospital. Kaplan-Meier method was used for survival analysis and Cox proportional hazards regression analysis predicted the hazard of death. Analysis revealed that the main treatment strategy was radiation combined with platinum for all stages except stage I. Cetuximab was employed in only 1% of cases. Kaplan-Meier analysis revealed stage II patients had poorer outcome than stage IV while Cox proportional hazard regression analysis (p = 0.4662) showed that stage I had a significantly lower hazard of death than stage IV (HR = 0.314; p = 0.0272). Contributory factors included tobacco and alcohol but body mass index (BMI) was inversely related to hazard of death. There was no difference in survival using any treatment modality for African Americans.

  13. Low-frequency centroid-moment-tensor inversion from superconducting-gravimeter data: The effect of seismic attenuation

    NASA Astrophysics Data System (ADS)

    Zábranová, Eliška; Matyska, Ctirad

    2014-10-01

    After the 2010 Maule and 2011 Tohoku earthquakes the spheroidal modes up to 1 mHz were clearly registered by the Global Geodynamic Project (GGP) network of superconducting gravimeters (SG). Fundamental parameters in synthetic calculations of the signals are the quality factors of the modes. We study the role of their uncertainties in the centroid-moment-tensor (CMT) inversions. First, we have inverted the SG data from selected GGP stations to jointly determine the quality factors of these normal modes and the three low-frequency CMT components, Mrr,(Mϑϑ-Mφφ)/2 and Mϑφ, that generate the observed SG signal. We have used several-days-long records to minimize the trade-off between the quality factors and the CMT but it was not eliminated completely. We have also inverted each record separately to get error estimates of the obtained parameters. Consequently, we have employed the GGP records of 60-h lengths for several published modal-quality-factor sets and inverted only the same three CMT components. The obtained CMT tensors are close to the solution from the joint Q-CMT inversion of longer records and resulting variability of the CMT components is smaller than differences among routine agency solutions. Reliable low-frequency CMT components can thus be obtained for any quality factors from the studied sets.

  14. Cognitive abilities and motivational processes in high school students' science achievement and engagement

    NASA Astrophysics Data System (ADS)

    Lau, Shun

    The dissertation presents two analytic approaches, a variable-centered and person-centered approach, to investigating holistic patterns of the cognitive, motivational, and affective correlates of science achievement and engagement in a sample of 491 10th and 11th grade high-school students. Building on Snow's (1989) idea of two pathways to achievement outcomes, Study 1 adopted a variable-centered approach to examining how cognitive and motivational factors associated with the performance and commitment pathways, respectively, contributed to the prediction of achievement outcomes in science. Results of hierarchical regression analyses showed that (a) students' cognitive abilities were the strongest predictors of their performance in science as measured by standardized test scores; (b) motivational processes enhanced the predictive validity for science test scores and grades beyond the variance accounted for by ability and demography; (c) motivational processes were the strongest predictors of students' commitment to science in the form of situational engagement and anticipated choices of science-related college majors and careers; and (d) competence beliefs served as a point of contact between the performance and commitment pathways. These results are consistent with Snow's (1989) conjecture that both performance and commitment pathway-related factors are necessary for understanding the full range of person-level inputs to achievement outcomes. Study 2 adopted a person-centered approach to examining holistic organizations of psychological factors within individuals and their relations to science achievement and engagement. Four types of students characterized by unique configurations of cognitive, motivational, and affective attributes were identified in both the male and female subsamples using inverse factor analysis. Type membership was found to distinguish students in various indicators of science achievement and engagement. Two of the four types were also found to generalize across gender groups. These two generalizable types resembled the mastery-oriented and helpless patterns identified in motivational research and the resilient and overcontrolled patterns identified in personality research. Study 2 provides empirical evidence for the replicability, generalizability, and validity of the identified types in the domain of science. It also demonstrates the importance of examining holistic patterns of individuals' psychological profiles and the utility of inverse factor analysis in person-centered research.

  15. Environmental and phenotype-related risk factors for owner-reported allergic/atopic skin symptoms and for canine atopic dermatitis verified by veterinarian in a Finnish dog population.

    PubMed

    Anturaniemi, Johanna; Uusitalo, Liisa; Hielm-Björkman, Anna

    2017-01-01

    The aim of this cross-sectional study was to observe whether environmental factors and phenotypic traits are associated with owner-reported skin problems and with veterinary diagnosed canine atopic dermatitis (CAD). Data were collected using the validated online DOGRISK questionnaire. Out of the data that the questionnaire provides for analysis, focus was first turned towards addressing questions regarding 'Atopy/allergy (skin symptoms)' using a total of 8643 dogs: 1585 dogs with owner-reported allergic/atopic skin symptoms and 7058 dogs without. A subsequent analysis compared dogs with veterinary-verified CAD (n = 322) as a case group against the 7058 dogs without owner-reported skin symptoms. The association between 21 factors related to the environment, canine phenotypes and breed groups within both populations were analysed using univariable and multivariable logistic regression. The environmental factors that showed a significant inverse association with the risk of owner-reported allergic/atopic skin symptoms were as following: whether the dog was living in a detached house, whether there were other dogs in the household, and whether the dog was born in the current household. Having over 50% white colour in the coat and living in an extremely clean household were significantly associated with an increased risk of owner-reported allergic/atopic skin symptoms. The five breeds demonstrating the highest proportion of owner-reported allergic/atopic skin symptoms were West Highland white terrier, Boxer, English bulldog, Dalmatian and French bulldog. The Fédération Cynologique Internationale dog breed groups 3 (Terriers) and 6 (Scent hounds and related breeds) showed a significantly higher risk for owner-reported allergic/atopic skin symptoms than mixed breed dogs. In the second population, the inverse association was observed between the risk of CAD and the presence of other dogs in the household, and whether the dog had been born in the current household. The results indicate that some environmental factors and canine phenotypes are associated with CAD and owner-reported skin symptoms, but they still do not prove causality.

  16. Environmental and phenotype-related risk factors for owner-reported allergic/atopic skin symptoms and for canine atopic dermatitis verified by veterinarian in a Finnish dog population

    PubMed Central

    Uusitalo, Liisa; Hielm-Björkman, Anna

    2017-01-01

    The aim of this cross-sectional study was to observe whether environmental factors and phenotypic traits are associated with owner-reported skin problems and with veterinary diagnosed canine atopic dermatitis (CAD). Data were collected using the validated online DOGRISK questionnaire. Out of the data that the questionnaire provides for analysis, focus was first turned towards addressing questions regarding ‘Atopy/allergy (skin symptoms)’ using a total of 8643 dogs: 1585 dogs with owner-reported allergic/atopic skin symptoms and 7058 dogs without. A subsequent analysis compared dogs with veterinary-verified CAD (n = 322) as a case group against the 7058 dogs without owner-reported skin symptoms. The association between 21 factors related to the environment, canine phenotypes and breed groups within both populations were analysed using univariable and multivariable logistic regression. The environmental factors that showed a significant inverse association with the risk of owner-reported allergic/atopic skin symptoms were as following: whether the dog was living in a detached house, whether there were other dogs in the household, and whether the dog was born in the current household. Having over 50% white colour in the coat and living in an extremely clean household were significantly associated with an increased risk of owner-reported allergic/atopic skin symptoms. The five breeds demonstrating the highest proportion of owner-reported allergic/atopic skin symptoms were West Highland white terrier, Boxer, English bulldog, Dalmatian and French bulldog. The Fédération Cynologique Internationale dog breed groups 3 (Terriers) and 6 (Scent hounds and related breeds) showed a significantly higher risk for owner-reported allergic/atopic skin symptoms than mixed breed dogs. In the second population, the inverse association was observed between the risk of CAD and the presence of other dogs in the household, and whether the dog had been born in the current household. The results indicate that some environmental factors and canine phenotypes are associated with CAD and owner-reported skin symptoms, but they still do not prove causality. PMID:28570617

  17. Functional beliefs and risk minimizing beliefs among Thai healthcare workers in Maharaj Nakorn Chiang Mai hospital: its association with intention to quit tobacco and alcohol.

    PubMed

    Jiraniramai, Surin; Jiraporncharoen, Wichuda; Pinyopornpanish, Kanokporn; Jakkaew, Nalinee; Wongpakaran, Tinakon; Angkurawaranon, Chaisiri

    2017-07-12

    Individual health beliefs are likely to play a key role in how people respond to knowledge and information about the potential harm from smoking and alcohol abuse. The objectives of the study were to 1) explore whether functional beliefs and risk minimizing beliefs were associated with intention to quit smoking and confidence to quit smoking and 2) explore whether functional beliefs and risk minimizing beliefs were associated with intention to quit alcohol drinking and confidence to quit alcohol drinking. A cross-sectional survey was conducted in 2013 among health care workers working in Thailand. Using predicted factor scores from factor analysis, the relationship between factor scores for each of the two beliefs and intention to quit and confidence to quit were tested using ANOVA and further adjusted for age and sex using linear regression. Functional beliefs were inversely associated with the intention to quit and confidence to quit smoking. Both functional beliefs and risk minimizing beliefs were each inversely associated with the intention to quit and confidence to quit alcohol drinking. Our study enhances the understanding of the complexities of health beliefs regarding these two commonly abused substances. As functional beliefs were associated with smoking and alcohol use, interventions to counter the cultural values and individual beliefs about the benefits of smoking and alcohol use are needed. Tackling risk minimizing beliefs by providing individualized feedback regarding harm may also be useful in alcohol drinkers.

  18. Quantitative analysis of SMEX'02 AIRSAR data for soil moisture inversion

    NASA Technical Reports Server (NTRS)

    Zyl, J. J. van; Njoku, E.; Jackson, T.

    2003-01-01

    This paper discusses in detail the characteristics of the AIRSAR data acquired, and provides an initial quantitative assessment of the accuracy of the radar inversion algorithms under these vegetated conditions.

  19. Psychosocial job factors and biological cardiovascular risk factors in Mexican workers.

    PubMed

    Garcia-Rojas, Isabel Judith; Choi, BongKyoo; Krause, Niklas

    2015-03-01

    Psychosocial job factors (PJF) have been implicated in the development of cardiovascular disease. The paucity of data from developing economies including Mexico hampers the development of worksite intervention efforts in those regions. This cross-sectional study of 2,330 Mexican workers assessed PJF (job strain [JS], social support [SS], and job insecurity [JI]) and biological cardiovascular disease risk factors [CVDRF] by questionnaire and on-site physical examinations. Alternative formulations of the JS scales were developed based on factor analysis and literature review. Associations between both traditional and alternative job factor scales with CVDRF were examined in multiple regression models, adjusting for physical workload, and socio-demographic factors. Alternative formulations of the job demand and control scales resulted in substantial changes in effect sizes or statistical significance when compared with the original scales. JS and JI showed hypothesized associations with most CVDRF, but they were inversely associated with diastolic blood pressure and some adiposity measures. SS was mainly protective against CVDRF. Among Mexican workers, alternative PJF scales predicted health outcomes better than traditional scales, and psychosocial stressors were associated with most CVDRF. © 2015 Wiley Periodicals, Inc.

  20. A Further Note on Generalized Hyperexponential Distributions

    DTIC Science & Technology

    1989-11-15

    functions. The inverse transform of each of m factors is of the form The requirement that 0, < r7 thus yields a mixture of an atom at the origin and a...real and (0, + 0,+,)/2 < Re(r/,) when (7h, 77t4) are a complex conjugate pair. Then the inverse transform of f*(s) is a probability distribution. To

  1. Factors Affecting Energy Barriers for Pyramidal Inversion in Amines and Phosphines: A Computational Chemistry Lab Exercise

    ERIC Educational Resources Information Center

    Montgomery, Craig D.

    2013-01-01

    An undergraduate exercise in computational chemistry that investigates the energy barrier for pyramidal inversion of amines and phosphines is presented. Semiempirical calculations (PM3) of the ground-state and transition-state energies for NR[superscript 1]R[superscript 2]R[superscript 3] and PR[superscript 1]R[superscript 2]R[superscript 3] allow…

  2. Number of Coronary Heart Disease Risk Factors and Mortality in Patients With First Myocardial Infarction

    PubMed Central

    Canto, John G.; Kiefe, Catarina I.; Rogers, William J.; Peterson, Eric D.; Frederick, Paul D.; French, William J.; Gibson, C. Michael; Pollack, Charles V.; Ornato, Joseph P.; Zalenski, Robert J.; Penney, Jan; Tiefenbrunn, Alan J.; Greenland, Philip

    2013-01-01

    Context Few studies have examined the association between the number of coronary heart disease risk factors and outcomes of acute myocardial infarction in community practice. Objective To determine the association between the number of coronary heart disease risk factors in patients with first myocardial infarction and hospital mortality. Design Observational study from the National Registry of Myocardial Infarction, 1994-2006. Patients We examined the presence and absence of 5 major traditional coronary heart disease risk factors (hypertension, smoking, dyslipidemia, diabetes, and family history of coronary heart disease) and hospital mortality among 542 008 patients with first myocardial infarction and without prior cardiovascular disease. Main Outcome Measure All-cause in-hospital mortality. Results A majority (85.6%) of patients who presented with initial myocardial infarction had at least 1 of the 5 coronary heart disease risk factors, and 14.4% had none of the 5 risk factors. Age varied inversely with the number of coronary heart disease risk factors, from a mean age of 71.5 years with 0 risk factors to 56.7 years with 5 risk factors (P for trend <.001). The total number of in-hospital deaths for all causes was 50 788. Unadjusted in-hospital mortality rates were 14.9%, 10.9%, 7.9%, 5.3%, 4.2%, and 3.6% for patients with 0, 1, 2, 3, 4, and 5 risk factors, respectively. After adjusting for age and other clinical factors, there was an inverse association between the number of coronary heart disease risk factors and hospital mortality adjusted odds ratio (1.54; 95% CI, 1.23-1.94) among individuals with 0 vs 5 risk factors. This association was consistent among several age strata and important patient subgroups. Conclusion Among patients with incident acute myocardial infarction without prior cardiovascular disease, in-hospital mortality was inversely related to the number of coronary heart disease risk factors. PMID:22089719

  3. Association between adolescent tobacco, alcohol and illicit drug use and individual and environmental resilience protective factors

    PubMed Central

    Hodder, Rebecca Kate; Freund, Megan; Bowman, Jenny; Gillham, Karen; Dray, Julia; Wiggers, John

    2016-01-01

    Objectives Research suggests that individual and environmental resilience protective factors may be associated with adolescent substance use; however, the associations between a broad range of such factors and use of various types of substances have not been examined. The study aimed to determine the association between a comprehensive range of adolescent individual and environmental resilience protective factors and measures of tobacco, alcohol and illicit substance use. Design Cross-sectional study. Setting 32 Australian secondary schools. Participants Grade 7–10 students (aged 11–17 years). Measures Data regarding 14 student individual and environmental resilience protective factors and seven substance use measures (tobacco, alcohol, marijuana, other illicit drug use) were obtained via an online self-report survey. Adjusted multivariate logistic regression analyses examined the association between all student resilience protective factors and seven substance use measures. Results Inverse univariate associations were found for 94 of 98 relationships examined (n=10 092). Multivariate analyses found: consistent inverse associations between 2 of 14 protective factors and all substance use measures (‘goals and aspirations’, ‘prosocial peers’); inverse associations between 4 protective factors with multiple substance use measures (‘home support’ (5 of 7), ‘school support’ (3 of 7), ‘self-awareness’ (2 of 7), ‘community meaningful participation’ (2 of 7)); positive associations between 2 resilience protective factors with multiple measures of substance use (‘community support’ (3 of 7), ‘peer caring relationships’ (5 of 7)) and 6 protective factors not to be associated with any substance use measure. Conclusions Despite individual relationships between the majority of resilience protective factors and substance use types, the protective benefit of such factors for adolescent substance use was limited to only a small number of such factors when considered collectively. Such results suggest that interventions seeking to reduce adolescent substance use may need to target specific protective factors to address specific types of substance use. Trial registration number ACTRN12611000606987, Results. PMID:27888175

  4. Pseudo 2D elastic waveform inversion for attenuation in the near surface

    NASA Astrophysics Data System (ADS)

    Wang, Yue; Zhang, Jie

    2017-08-01

    Seismic waveform propagation could be significantly affected by heterogeneities in the near surface zone (0 m-500 m depth). As a result, it is important to obtain as much near surface information as possible. Seismic attenuation, characterized by QP and QS factors, may affect seismic waveform in both phase and amplitude; however, it is rarely estimated and applied to the near surface zone for seismic data processing. Applying a 1D elastic full waveform modelling program, we demonstrate that such effects cannot be overlooked in the waveform computation if the value of the Q factor is lower than approximately 100. Further, we develop a pseudo 2D elastic waveform inversion method in the common midpoint (CMP) domain that jointly inverts early arrivals for QP and surface waves for QS. In this method, although the forward problem is in 1D, by applying 2D model regularization, we obtain 2D QP and QS models through simultaneous inversion. A cross-gradient constraint between the QP and Qs models is applied to ensure structural consistency of the 2D inversion results. We present synthetic examples and a real case study from an oil field in China.

  5. Silicosis prevalence and risk factors in semi-precious stone mining in Brazil.

    PubMed

    Souza, Tamires P; Watte, Guilherme; Gusso, Alaíde M; Souza, Rafaela; Moreira, José da S; Knorst, Marli M

    2017-06-01

    Underground mining generates large amounts of dust and exposes workers to silica. This study aims to determine the prevalence and predictor factors for the development of silicosis among semi-precious-stone mineworkers in southern Brazil working in a self-administered cooperative. In a cross-sectional study of 348 current workers and retirees, demographic data, medical, and occupational history were collected through an interview performed by a nurse and medical record review. Risk factor associations were studied by Poisson multivariate regression. The overall prevalence of silicosis was 37%, while in current miners it was 28%. Several risk factors for silicosis were identified in the univariate analysis. Inadequate ventilation in the underground galleries combined with dry drilling, duration of silica exposure, and (inversely) education remained significant in the multivariate analysis (P < 0.05). This study is unusual in studying semi-precious stone mineworkers in a self-administered worker cooperative with limited resources. The prevalence of silicosis was very high. A number of recommendations are made-including technical support for worker cooperatives, surveillance of silica exposure and silicosis, exposure reduction measures, and benefits allowing impaired miners to leave the industry. © 2017 Wiley Periodicals, Inc.

  6. Epidermal growth factor receptor (EGFr); results of a 6 year follow-up study in operable breast cancer with emphasis on the node negative subgroup.

    PubMed Central

    Nicholson, S.; Richard, J.; Sainsbury, C.; Halcrow, P.; Kelly, P.; Angus, B.; Wright, C.; Henry, J.; Farndon, J. R.; Harris, A. L.

    1991-01-01

    More accurate criteria are required for the selection of patients with node-negative breast cancer for systemic adjuvant therapy. Expression of epidermal growth factor receptor (EGFr) has been shown previously to be inversely related to oestrogen receptor (ER) in patients with operable breast cancer and to be associated with a poorer prognosis. Analysis of EGFr and ER was performed on tumour samples from 231 patients with operable breast cancer followed for up to 6 years after surgery. The median duration of follow-up in patients still alive at the time of analysis was 45 months. Thirty-five percent of patients (82) had tumours with greater than 10 fmol mg-1 I125-EGF binding (EGFr+) and 47% (109) and cystolic ER concentrations greater than 5 fmol mg-1 (ER+), with a marked inverse relationship between EGFr and ER (P less than 0.00001). In a univariate analysis EGFr was second only to axillary node status as a prognostic marker for all patients both in terms of relapse-free and overall survival (P less than 0.001, log rank). For patients with histologically negative axillary nodes EGFr was superior to ER in predicting relapse and survival (P less than 0.01 and P less than 0.005 respectively compared to P less than 0.1 and P less than 0.1, log rank). In a multivariate (Cox model) analysis only EGFr, out of EGFr, ER, size and grade, was predictive for either relapse-free or overall survival for patients with node-negative disease (P = 0.05 and P = 0.026 respectively). EGFr has been shown to be a marker of poor prognosis for patients with node-negative breast cancer. Since patients with EGFr+ tumours are unlikely to respond to hormone therapy it may be possible to select them for trials of systemic adjuvant chemotherapy. PMID:1846551

  7. Epidermal growth factor receptor (EGFr); results of a 6 year follow-up study in operable breast cancer with emphasis on the node negative subgroup.

    PubMed

    Nicholson, S; Richard, J; Sainsbury, C; Halcrow, P; Kelly, P; Angus, B; Wright, C; Henry, J; Farndon, J R; Harris, A L

    1991-01-01

    More accurate criteria are required for the selection of patients with node-negative breast cancer for systemic adjuvant therapy. Expression of epidermal growth factor receptor (EGFr) has been shown previously to be inversely related to oestrogen receptor (ER) in patients with operable breast cancer and to be associated with a poorer prognosis. Analysis of EGFr and ER was performed on tumour samples from 231 patients with operable breast cancer followed for up to 6 years after surgery. The median duration of follow-up in patients still alive at the time of analysis was 45 months. Thirty-five percent of patients (82) had tumours with greater than 10 fmol mg-1 I125-EGF binding (EGFr+) and 47% (109) and cystolic ER concentrations greater than 5 fmol mg-1 (ER+), with a marked inverse relationship between EGFr and ER (P less than 0.00001). In a univariate analysis EGFr was second only to axillary node status as a prognostic marker for all patients both in terms of relapse-free and overall survival (P less than 0.001, log rank). For patients with histologically negative axillary nodes EGFr was superior to ER in predicting relapse and survival (P less than 0.01 and P less than 0.005 respectively compared to P less than 0.1 and P less than 0.1, log rank). In a multivariate (Cox model) analysis only EGFr, out of EGFr, ER, size and grade, was predictive for either relapse-free or overall survival for patients with node-negative disease (P = 0.05 and P = 0.026 respectively). EGFr has been shown to be a marker of poor prognosis for patients with node-negative breast cancer. Since patients with EGFr+ tumours are unlikely to respond to hormone therapy it may be possible to select them for trials of systemic adjuvant chemotherapy.

  8. Crustal Thickness Mapping of the Rifted Margin Ocean-Continent Transition using Satellite Gravity Inversion Incorporating a Lithosphere Thermal Correction

    NASA Astrophysics Data System (ADS)

    Hurst, N. W.; Kusznir, N. J.

    2005-05-01

    A new method of inverting satellite gravity at rifted continental margins to give crustal thickness, incorporating a lithosphere thermal correction, has been developed which does not use a priori information about the location of the ocean-continent transition (OCT) and provides an independent prediction of OCT location. Satellite derived gravity anomaly data (Sandwell and Smith 1997) and bathymetry data (Gebco 2003) are used to derive the mantle residual gravity anomaly which is inverted in 3D in the spectral domain to give Moho depth. Oceanic lithosphere and stretched continental margin lithosphere produce a large negative residual thermal gravity anomaly (up to -380 mgal), which must be corrected for in order to determine Moho depth. This thermal gravity correction may be determined for oceanic lithosphere using oceanic isochron data, and for the thinned continental margin lithosphere using margin rift age and beta stretching estimates iteratively derived from crustal basement thickness determined from the gravity inversion. The gravity inversion using the thermal gravity correction predicts oceanic crustal thicknesses consistent with seismic observations, while that without the thermal correction predicts much too great oceanic crustal thicknesses. Predicted Moho depth and crustal thinning across the Hatton and Faroes rifted margins, using the gravity inversion with embedded thermal correction, compare well with those produced by wide-angle seismology. A new gravity inversion method has been developed in which no isochrons are used to define the thermal gravity correction. The new method assumes all lithosphere to be initially continental and a uniform lithosphere stretching age is used corresponding to the time of continental breakup. The thinning factor produced by the gravity inversion is used to predict the thickness of oceanic crust. This new modified form of gravity inversion with embedded thermal correction provides an improved estimate of rifted continental margin crustal thinning and an improved (and isochron independent) prediction of OCT location. The new method uses an empirical relationship to predict the thickness of oceanic crust as a function of lithosphere thinning factor controlled by two input parameters: a critical thinning factor for the start of ocean crust production and the maximum oceanic crustal thickness produced when the thinning factor = 1, corresponding to infinite lithosphere stretching. The disadvantage of using a uniform stretching age corresponding to the age of continental breakup is that the inversion fails to predict increasing thermal gravity correction towards the ocean ridge and incorrectly predicts thickening of oceanic crust with decreasing oceanic age. The new gravity inversion method has been applied to N. Atlantic rifted margins. This work forms part of the NERC Margins iSIMM project. iSIMM investigators are from Liverpool and Cambridge Universities, Badley Geoscience & Schlumberger Cambridge Research supported by the NERC, the DTI, Agip UK, BP, Amerada Hess Ltd, Anadarko, ConocoPhillips, Shell, Statoil and WesternGeco. The iSIMM team comprises NJ Kusznir, RS White, AM Roberts, PAF Christie, A Chappell, J Eccles, R Fletcher, D Healy, N Hurst, ZC Lunnon, CJ Parkin, AW Roberts, LK Smith, V Tymms & R Spitzer.

  9. Conserved Features in the Structure, Mechanism, and Biogenesis of the Inverse Autotransporter Protein Family

    PubMed Central

    Heinz, Eva; Stubenrauch, Christopher J.; Grinter, Rhys; Croft, Nathan P.; Purcell, Anthony W.; Strugnell, Richard A.; Dougan, Gordon; Lithgow, Trevor

    2016-01-01

    The bacterial cell surface proteins intimin and invasin are virulence factors that share a common domain structure and bind selectively to host cell receptors in the course of bacterial pathogenesis. The β-barrel domains of intimin and invasin show significant sequence and structural similarities. Conversely, a variety of proteins with sometimes limited sequence similarity have also been annotated as “intimin-like” and “invasin” in genome datasets, while other recent work on apparently unrelated virulence-associated proteins ultimately revealed similarities to intimin and invasin. Here we characterize the sequence and structural relationships across this complex protein family. Surprisingly, intimins and invasins represent a very small minority of the sequence diversity in what has been previously the “intimin/invasin protein family”. Analysis of the assembly pathway for expression of the classic intimin, EaeA, and a characteristic example of the most prevalent members of the group, FdeC, revealed a dependence on the translocation and assembly module as a common feature for both these proteins. While the majority of the sequences in the grouping are most similar to FdeC, a further and widespread group is two-partner secretion systems that use the β-barrel domain as the delivery device for secretion of a variety of virulence factors. This comprehensive analysis supports the adoption of the “inverse autotransporter protein family” as the most accurate nomenclature for the family and, in turn, has important consequences for our overall understanding of the Type V secretion systems of bacterial pathogens. PMID:27190006

  10. Differences in within- and between-person factor structure of positive and negative affect: analysis of two intensive measurement studies using multilevel structural equation modeling.

    PubMed

    Rush, Jonathan; Hofer, Scott M

    2014-06-01

    The Positive and Negative Affect Schedule (PANAS) is a widely used measure of emotional experience. The factor structure of the PANAS has been examined predominantly with cross-sectional designs, which fails to disaggregate within-person variation from between-person differences. There is still uncertainty as to the factor structure of positive and negative affect and whether they constitute 2 distinct independent factors. The present study examined the within-person and between-person factor structure of the PANAS in 2 independent samples that reported daily affect over 7 and 14 occasions, respectively. Results from multilevel confirmatory factor analyses revealed that a 2-factor structure at both the within-person and between-person levels, with correlated specific factors for overlapping items, provided good model fit. The best-fitting solution was one where within-person factors of positive and negative affect were inversely correlated, but between-person factors were independent. The structure was further validated through multilevel structural equation modeling examining the effects of cognitive interference, daily stress, physical symptoms, and physical activity on positive and negative affect factors.

  11. 1r2dinv: A finite-difference model for inverse analysis of two dimensional linear or radial groundwater flow

    USGS Publications Warehouse

    Bohling, Geoffrey C.; Butler, J.J.

    2001-01-01

    We have developed a program for inverse analysis of two-dimensional linear or radial groundwater flow problems. The program, 1r2dinv, uses standard finite difference techniques to solve the groundwater flow equation for a horizontal or vertical plane with heterogeneous properties. In radial mode, the program simulates flow to a well in a vertical plane, transforming the radial flow equation into an equivalent problem in Cartesian coordinates. The physical parameters in the model are horizontal or x-direction hydraulic conductivity, anisotropy ratio (vertical to horizontal conductivity in a vertical model, y-direction to x-direction in a horizontal model), and specific storage. The program allows the user to specify arbitrary and independent zonations of these three parameters and also to specify which zonal parameter values are known and which are unknown. The Levenberg-Marquardt algorithm is used to estimate parameters from observed head values. Particularly powerful features of the program are the ability to perform simultaneous analysis of heads from different tests and the inclusion of the wellbore in the radial mode. These capabilities allow the program to be used for analysis of suites of well tests, such as multilevel slug tests or pumping tests in a tomographic format. The combination of information from tests stressing different vertical levels in an aquifer provides the means for accurately estimating vertical variations in conductivity, a factor profoundly influencing contaminant transport in the subsurface. ?? 2001 Elsevier Science Ltd. All rights reserved.

  12. Cross-sectional survey of workload and burnout among Japanese physicians working in stroke care: the nationwide survey of acute stroke care capacity for proper designation of comprehensive stroke center in Japan (J-ASPECT) study.

    PubMed

    Nishimura, Kunihiro; Nakamura, Fumiaki; Takegami, Misa; Fukuhara, Schunichi; Nakagawara, Jyoji; Ogasawara, Kuniaki; Ono, Junichi; Shiokawa, Yoshiaki; Miyachi, Shigeru; Nagata, Izumi; Toyoda, Kazunori; Matsuda, Shinya; Kataoka, Hiroharu; Miyamoto, Yoshihiro; Kitaoka, Kazuyo; Kada, Akiko; Iihara, Koji

    2014-05-01

    Burnout is common among physicians and affects the quality of care. We aimed to determine the prevalence of burnout among Japanese physicians working in stroke care and evaluate personal and professional characteristics associated with burnout. A cross-sectional design was used to develop and distribute a survey to 11 211 physicians. Physician burnout was assessed using the Maslach Burnout Inventory General Survey. The predictors of burnout and the relationships among them were identified by multivariable logistic regression analysis. A total of 2724 (25.3%) physicians returned the surveys. After excluding those who were not working in stroke care or did not complete the survey appropriately, 2564 surveys were analyzed. Analysis of the participants' scores revealed that 41.1% were burned out. Multivariable analysis indicated that number of hours worked per week is positively associated with burnout. Hours slept per night, day-offs per week, years of experience, as well as income, are inversely associated with burnout. Short Form 36 mental health subscale was also inversely associated with burnout. The primary risk factors for burnout are heavy workload, short sleep duration, relatively little experience, and low mental quality of life. Prospective research is required to confirm these findings and develop programs for preventing burnout. © 2014 American Heart Association, Inc.

  13. Association of vitamin C with the risk of age-related cataract: a meta-analysis.

    PubMed

    Wei, Lin; Liang, Ge; Cai, Chunmei; Lv, Jin

    2016-05-01

    Whether vitamin C is a protective factor for age-related cataract remains unclear. Thus, we conducted a meta-analysis to summarize the evidence from epidemiological studies of vitamin C and the risk of age-related cataract. Pertinent studies were identified by searching in PubMed and in Webscience. The random effect model was used to combine the results. Meta-regression and subgroups analyses were used to explore potential sources of between-study heterogeneity. Publication bias was estimated using Egger's regression asymmetry test. Finally, 15 articles with 20 studies for vitamin C intake and eight articles with 10 studies for serum ascorbate were included in this meta-analysis. The relative risk (RR) and 95% confidence interval of cataract for the highest versus the lowest category of vitamin C intake was 0.814 (0.707-0.938), and the associations were significant in America and Asia. Significant association of cataract risk with highest versus the lowest category of serum ascorbate was found in general [0.704 (0.564-0.879)]. Inverse associations were also found between serum ascorbate and nuclear cataract and posterior subcapsular cataract. Higher vitamin C intake and serum ascorbate might be inversely associated with risk of cataract. Vitamin C intake should be advocated for the primary prevention of cataract. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  14. Three-dimensional magnetotelluric inversion in practice—the electrical conductivity structure of the San Andreas Fault in Central California

    NASA Astrophysics Data System (ADS)

    Tietze, Kristina; Ritter, Oliver

    2013-10-01

    3-D inversion techniques have become a widely used tool in magnetotelluric (MT) data interpretation. However, with real data sets, many of the controlling factors for the outcome of 3-D inversion are little explored, such as alignment of the coordinate system, handling and influence of data errors and model regularization. Here we present 3-D inversion results of 169 MT sites from the central San Andreas Fault in California. Previous extensive 2-D inversion and 3-D forward modelling of the data set revealed significant along-strike variation of the electrical conductivity structure. 3-D inversion can recover these features but only if the inversion parameters are tuned in accordance with the particularities of the data set. Based on synthetic 3-D data we explore the model space and test the impacts of a wide range of inversion settings. The tests showed that the recovery of a pronounced regional 2-D structure in inversion of the complete impedance tensor depends on the coordinate system. As interdependencies between data components are not considered in standard 3-D MT inversion codes, 2-D subsurface structures can vanish if data are not aligned with the regional strike direction. A priori models and data weighting, that is, how strongly individual components of the impedance tensor and/or vertical magnetic field transfer functions dominate the solution, are crucial controls for the outcome of 3-D inversion. If deviations from a prior model are heavily penalized, regularization is prone to result in erroneous and misleading 3-D inversion models, particularly in the presence of strong conductivity contrasts. A `good' overall rms misfit is often meaningless or misleading as a huge range of 3-D inversion results exist, all with similarly `acceptable' misfits but producing significantly differing images of the conductivity structures. Reliable and meaningful 3-D inversion models can only be recovered if data misfit is assessed systematically in the frequency-space domain.

  15. Influence of the Redundant Verification and the Non-Redundant Verification on the Hydraulic Tomography

    NASA Astrophysics Data System (ADS)

    Wei, T. B.; Chen, Y. L.; Lin, H. R.; Huang, S. Y.; Yeh, T. C. J.; Wen, J. C.

    2016-12-01

    In the groundwater study, it estimated the heterogeneous spatial distribution of hydraulic Properties, there were many scholars use to hydraulic tomography (HT) from field site pumping tests to estimate inverse of heterogeneous spatial distribution of hydraulic Properties, to prove the most of most field site aquifer was heterogeneous hydrogeological parameters spatial distribution field. Many scholars had proposed a method of hydraulic tomography to estimate heterogeneous spatial distribution of hydraulic Properties of aquifer, the Huang et al. [2011] was used the non-redundant verification analysis of pumping wells changed, observation wells fixed on the inverse and the forward, to reflect the feasibility of the heterogeneous spatial distribution of hydraulic Properties of field site aquifer of the non-redundant verification analysis on steady-state model.From post literature, finding only in steady state, non-redundant verification analysis of pumping well changed location and observation wells fixed location for inverse and forward. But the studies had not yet pumping wells fixed or changed location, and observation wells fixed location for redundant verification or observation wells change location for non-redundant verification of the various combinations may to explore of influences of hydraulic tomography method. In this study, it carried out redundant verification method and non-redundant verification method for forward to influences of hydraulic tomography method in transient. And it discuss above mentioned in NYUST campus sites the actual case, to prove the effectiveness of hydraulic tomography methods, and confirmed the feasibility on inverse and forward analysis from analysis results.Keywords: Hydraulic Tomography, Redundant Verification, Heterogeneous, Inverse, Forward

  16. Air and Ground Surface Temperature Relations in a Mountainous Basin, Wolf Creek, Yukon Territory

    NASA Astrophysics Data System (ADS)

    Roadhouse, Emily A.

    The links between climate and permafrost are well known, but the precise nature of the relationship between air and ground temperatures remains poorly understood, particularly in complex mountain environments. Although previous studies indicate that elevation and potential incoming solar radiation (PISR) are the two leading factors contributing to the existence of permafrost at a given location, additional factors may also contribute significantly to the existence of mountain permafrost, including vegetation cover, snow accumulation and the degree to which individual mountain landscapes are prone to air temperature inversions. Current mountain permafrost models consider only elevation and aspect, and have not been able to deal with inversion effects in a systematic fashion. This thesis explores the relationship between air and ground surface temperatures and the presence of surface-based inversions at 27 sites within the Wolf Creek basin and surrounding area between 2001 and 2006, as a first step in developing an improved permafrost distribution TTOP model. The TTOP model describes the relationship between the mean annual air temperature and the temperature at the top of permafrost in terms of the surface and thermal offsets (Smith and Riseborough, 2002). Key components of this model are n-factors which relate air and ground climate by establishing the ratio between air and surface freezing (winter) and thawing (summer) degree-days, thus summarizing the surface energy balance on a seasonal basis. Here we examine (1) surface offsets and (2) freezing and thawing n-factor variability at a number of sites through altitudinal treeline in the southern Yukon. Thawing n-factors (nt) measured at individual sites remained relatively constant from one year to the next and may be related to land cover. During the winter, the insulating effect of a thick snow cover results in higher surface temperatures, while thin snow cover results in low surface temperatures more closely related to the winter air temperatures. The application of n-factor modeling techniques within the permafrost region, and the verification of these techniques for a range of natural surfaces, is essential to the determination of the thermal and physical response to potential climate warming in permafrost regions. The presence of temperature inversions presents a unique challenge to permafrost probability mapping in mountainous terrain. While elsewhere the existence of permafrost can be linearly related to elevation, the presence of frequent inversions challenges this assumption, affecting permafrost distribution in ways that the current modeling techniques cannot accurately predict. At sites across the Yukon, inversion-prone sites were predominantly situated in U-shaped valleys, although open slopes, mid-slope ridges and plains were also identified. Within the Wolf Creek basin and surrounding area, inversion episodes have a measurable effect on local air temperatures, occurring during the fall and winter seasons along the Mount Sima trail, and year-round in the palsa valley. Within the discontinuous permafrost zone, where average surface temperatures are often close to zero, even a relatively small change in temperature in the context of future climate change could have a widespread impact on permafrost distribution.

  17. Approximate non-linear multiparameter inversion for multicomponent single and double P-wave scattering in isotropic elastic media

    NASA Astrophysics Data System (ADS)

    Ouyang, Wei; Mao, Weijian

    2018-03-01

    An asymptotic quadratic true-amplitude inversion method for isotropic elastic P waves is proposed to invert medium parameters. The multicomponent P-wave scattered wavefield is computed based on a forward relationship using second-order Born approximation and corresponding high-frequency ray theoretical methods. Within the local double scattering mechanism, the P-wave transmission factors are elaborately calculated, which results in the radiation pattern for P-waves scattering being a quadratic combination of the density and Lamé's moduli perturbation parameters. We further express the elastic P-wave scattered wavefield in a form of generalized Radon transform (GRT). After introducing classical backprojection operators, we obtain an approximate solution of the inverse problem by solving a quadratic non-linear system. Numerical tests with synthetic data computed by finite-differences scheme demonstrate that our quadratic inversion can accurately invert perturbation parameters for strong perturbations, compared with the P-wave single-scattering linear inversion method. Although our inversion strategy here is only syncretized with P-wave scattering, it can be extended to invert multicomponent elastic data containing both P-wave and S-wave information.

  18. Inverse simulation system for evaluating handling qualities during rendezvous and docking

    NASA Astrophysics Data System (ADS)

    Zhou, Wanmeng; Wang, Hua; Thomson, Douglas; Tang, Guojin; Zhang, Fan

    2017-08-01

    The traditional method used for handling qualities assessment of manned space vehicles is too time-consuming to meet the requirements of an increasingly fast design process. In this study, a rendezvous and docking inverse simulation system to assess the handling qualities of spacecraft is proposed using a previously developed model-predictive-control architecture. By considering the fixed discrete force of the thrusters of the system, the inverse model is constructed using the least squares estimation method with a hyper-ellipsoidal restriction, the continuous control outputs of which are subsequently dispersed by pulse width modulation with sensitivity factors introduced. The inputs in every step are deemed constant parameters, and the method could be considered as a general method for solving nominal, redundant, and insufficient inverse problems. The rendezvous and docking inverse simulation is applied to a nine-degrees-of-freedom platform, and a novel handling qualities evaluation scheme is established according to the operation precision and astronauts' workload. Finally, different nominal trajectories are scored by the inverse simulation and an established evaluation scheme. The scores can offer theoretical guidance for astronaut training and more complex operation missions.

  19. Approximate nonlinear multiparameter inversion for multicomponent single and double P-wave scattering in isotropic elastic media

    NASA Astrophysics Data System (ADS)

    Ouyang, Wei; Mao, Weijian

    2018-07-01

    An asymptotic quadratic true-amplitude inversion method for isotropic elastic P waves is proposed to invert medium parameters. The multicomponent P-wave scattered wavefield is computed based on a forward relationship using second-order Born approximation and corresponding high-frequency ray theoretical methods. Within the local double scattering mechanism, the P-wave transmission factors are elaborately calculated, which results in the radiation pattern for P-wave scattering being a quadratic combination of the density and Lamé's moduli perturbation parameters. We further express the elastic P-wave scattered wavefield in a form of generalized Radon transform. After introducing classical backprojection operators, we obtain an approximate solution of the inverse problem by solving a quadratic nonlinear system. Numerical tests with synthetic data computed by finite-differences scheme demonstrate that our quadratic inversion can accurately invert perturbation parameters for strong perturbations, compared with the P-wave single-scattering linear inversion method. Although our inversion strategy here is only syncretized with P-wave scattering, it can be extended to invert multicomponent elastic data containing both P- and S-wave information.

  20. Whole-tumour diffusion kurtosis MR imaging histogram analysis of rectal adenocarcinoma: Correlation with clinical pathologic prognostic factors.

    PubMed

    Cui, Yanfen; Yang, Xiaotang; Du, Xiaosong; Zhuo, Zhizheng; Xin, Lei; Cheng, Xintao

    2018-04-01

    To investigate potential relationships between diffusion kurtosis imaging (DKI)-derived parameters using whole-tumour volume histogram analysis and clinicopathological prognostic factors in patients with rectal adenocarcinoma. 79 consecutive patients who underwent MRI examination with rectal adenocarcinoma were retrospectively evaluated. Parameters D, K and conventional ADC were measured using whole-tumour volume histogram analysis. Student's t-test or Mann-Whitney U-test, receiver operating characteristic curves and Spearman's correlation were used for statistical analysis. Almost all the percentile metrics of K were correlated positively with nodal involvement, higher histological grades, the presence of lymphangiovascular invasion (LVI) and circumferential margin (CRM) (p<0.05), with the exception of between K 10th , K 90th and histological grades. In contrast, significant negative correlations were observed between 25th, 50th percentiles and mean values of ADC and D, as well as ADC 10th , with tumour T stages (p< 0.05). Meanwhile, lower 75th and 90th percentiles of ADC and D values were also correlated inversely with nodal involvement (p< 0.05). K mean showed a relatively higher area under the curve (AUC) and higher specificity than other percentiles for differentiation of lesions with nodal involvement. DKI metrics with whole-tumour volume histogram analysis, especially K parameters, were associated with important prognostic factors of rectal cancer. • K correlated positively with some important prognostic factors of rectal cancer. • K mean showed higher AUC and specificity for differentiation of nodal involvement. • DKI metrics with whole-tumour volume histogram analysis depicted tumour heterogeneity.

  1. Fully Nonlinear Modeling and Analysis of Precision Membranes

    NASA Technical Reports Server (NTRS)

    Pai, P. Frank; Young, Leyland G.

    2003-01-01

    High precision membranes are used in many current space applications. This paper presents a fully nonlinear membrane theory with forward and inverse analyses of high precision membrane structures. The fully nonlinear membrane theory is derived from Jaumann strains and stresses, exact coordinate transformations, the concept of local relative displacements, and orthogonal virtual rotations. In this theory, energy and Newtonian formulations are fully correlated, and every structural term can be interpreted in terms of vectors. Fully nonlinear ordinary differential equations (ODES) governing the large static deformations of known axisymmetric membranes under known axisymmetric loading (i.e., forward problems) are presented as first-order ODES, and a method for obtaining numerically exact solutions using the multiple shooting procedure is shown. A method for obtaining the undeformed geometry of any axisymmetric membrane with a known inflated geometry and a known internal pressure (i.e., inverse problems) is also derived. Numerical results from forward analysis are verified using results in the literature, and results from inverse analysis are verified using known exact solutions and solutions from the forward analysis. Results show that the membrane theory and the proposed numerical methods for solving nonlinear forward and inverse membrane problems are accurate.

  2. FAST INVERSION OF SOLAR Ca II SPECTRA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Beck, C.; Choudhary, D. P.; Rezaei, R.

    We present a fast (<<1 s per profile) inversion code for solar Ca II lines. The code uses an archive of spectra that are synthesized prior to the inversion under the assumption of local thermodynamic equilibrium (LTE). We show that it can be successfully applied to spectrograph data or more sparsely sampled spectra from two-dimensional spectrometers. From a comparison to a non-LTE inversion of the same set of spectra, we derive a first-order non-LTE correction to the temperature stratifications derived in the LTE approach. The correction factor is close to unity up to log τ ∼ –3 and increases to valuesmore » of 2.5 and 4 at log τ = –6 in the quiet Sun and the umbra, respectively.« less

  3. Cruciferous Vegetable Intake Is Inversely Associated with Lung Cancer Risk among Current Nonsmoking Men in the Japan Public Health Center (JPHC) Study.

    PubMed

    Mori, Nagisa; Shimazu, Taichi; Sasazuki, Shizuka; Nozue, Miho; Mutoh, Michihiro; Sawada, Norie; Iwasaki, Motoki; Yamaji, Taiki; Inoue, Manami; Takachi, Ribeka; Sunami, Ayaka; Ishihara, Junko; Sobue, Tomotaka; Tsugane, Shoichiro

    2017-05-01

    Background: Cruciferous vegetables, a rich source of isothiocyanates, have been reported to lower the risk of several types of cancer, including lung cancer. However, evidence from prospective observations of populations with a relatively high intake of cruciferous vegetables is sparse. Objective: We investigated the association between cruciferous vegetable intake and lung cancer risk in a large-scale population-based prospective study in Japan. Methods: We studied 82,330 participants (38,663 men; 43,667 women) aged 45-74 y without a past history of cancer. Participants were asked to respond to a validated questionnaire that included 138 food items. The association between cruciferous vegetable intake and lung cancer incidence was assessed with the use of Cox proportional hazard regression analysis to estimate HRs and 95% CIs (with adjustments for potential confounding factors). Results: After 14.9 y of follow-up, a total of 1499 participants (1087 men; 412 women) were diagnosed with lung cancer. After deleting early-diagnosed cancer and adjusting for confounding factors, we observed a nonsignificant inverse trend between cruciferous vegetable intake and lung cancer risk in men in the highest compared with the lowest quartiles (multivariate HR: 0.85; 95% CI: 0.69, 1.06; P -trend = 0.13). Stratified analysis by smoking status revealed a significant inverse association between cruciferous vegetable intake and lung cancer risk among those who were never smokers and those who were past smokers after deleting lung cancer cases in the first 3 y of follow-up [multivariate HR for never smokers: 0.49 (95% CI: 0.27, 0.87; P -trend = 0.04); multivariate HR for past smokers: 0.59 (95% CI: 0.35, 0.99; P -trend = 0.10)]. No association was noted in men who were current smokers and women who were never smokers. Conclusion: This study suggests that cruciferous vegetable intake may be associated with a reduction in lung cancer risk among men who are currently nonsmokers. © 2017 American Society for Nutrition.

  4. Comparison of Mammographic Density Assessed as Volumes and Areas among Women Undergoing Diagnostic Image-Guided Breast Biopsy

    PubMed Central

    Gierach, Gretchen L.; Geller, Berta M.; Shepherd, John A.; Patel, Deesha A.; Vacek, Pamela M.; Weaver, Donald L.; Chicoine, Rachael E.; Pfeiffer, Ruth M.; Fan, Bo; Mahmoudzadeh, Amir Pasha; Wang, Jeff; Johnson, Jason M.; Herschorn, Sally D.; Brinton, Louise A.; Sherman, Mark E.

    2014-01-01

    Background Mammographic density (MD), the area of non-fatty appearing tissue divided by total breast area, is a strong breast cancer risk factor. Most MD analyses have employed visual categorizations or computer-assisted quantification, which ignore breast thickness. We explored MD volume and area, using a volumetric approach previously validated as predictive of breast cancer risk, in relation to risk factors among women undergoing breast biopsy. Methods Among 413 primarily white women, ages 40–65, undergoing diagnostic breast biopsies between 2007–2010 at an academic facility in Vermont, MD volume (cm3) was quantified in cranio-caudal views of the breast contralateral to the biopsy target using a density phantom, while MD area (cm2) was measured on the same digital mammograms using thresholding software. Risk factor associations with continuous MD measurements were evaluated using linear regression. Results Percent MD volume and area were correlated (r=0.81) and strongly and inversely associated with age, body mass index (BMI), and menopause. Both measures were inversely associated with smoking and positively associated with breast biopsy history. Absolute MD measures were correlated (r=0.46) and inversely related to age and menopause. Whereas absolute dense area was inversely associated with BMI, absolute dense volume was positively associated. Conclusions Volume and area MD measures exhibit some overlap in risk factor associations, but divergence as well, particularly for BMI. Impact Findings suggest that volume and area density measures differ in subsets of women; notably, among obese women, absolute density was higher with volumetric methods, suggesting that breast cancer risk assessments may vary for these techniques. PMID:25139935

  5. Perceived Reasons for Living at Index Hospitalization and Future Suicide Attempt

    PubMed Central

    Lizardi, Dana; Currier, Diane; Galfalvy, Hanga; Sher, Leo; Burke, Ainsley; Mann, John; Oquendo, Maria

    2013-01-01

    It is unclear why certain individuals choose not to engage in suicidal behavior. Although important, protective factors against suicidal behavior have seldom been studied. The Reasons for Living Inventory is a measure of putative protective factors that is inversely related to a history of suicide attempts, but its predictive utility remains relatively untested. This study sought to determine whether the Reasons for Living Inventory predicts future suicide attempts over a 2-year period. Depressed inpatients were assessed for reasons for living and were followed for 2 years. Follow-up interviews took place at 3 months, 1 year, and 2 years after discharge from the index hospitalization. Survival analysis indicates a high score on the Reasons for Living Inventory predicted fewer future suicide attempts within a 2-year period in women but not in men. Perceived reasons for living serve as protective factors against suicide attempt in women and not in men. PMID:17502812

  6. Assessing social support among South Asians: the multidimensional scale of perceived social support.

    PubMed

    Tonsing, Kareen; Zimet, Gregory D; Tse, Samson

    2012-06-01

    The psychometric properties of the Multidimensional Scale of Perceived Social Support (MSPSS) of the Urdu (MSPSS-U) and Nepali (MSPSS-N) versions were investigated among Pakistani (n=148) and Nepalese (n=153) respondents living in Hong Kong. The factor analysis of the MSPSS-N conducted in this study confirmed the three factors of the original MSPSS, namely, Family, Friend, and Significant Others, while only two factors were extracted from the MSPSS-U (i.e., the Family and Friends subscales). With regard to construct validity, both the MSPSS-U and MSPSS-N were inversely correlated with depression, anxiety and stress as assessed by the Depression Anxiety Stress Scale (DASS-21). The internal reliability and construct validity of the MSPSS-U and MSPSS-N were also established and provided support for the validity of both versions as tools for measuring perceived social support among South Asian migrants. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Spatial diffusion of influenza outbreak-related climate factors in Chiang Mai Province, Thailand.

    PubMed

    Nakapan, Supachai; Tripathi, Nitin Kumar; Tipdecho, Taravudh; Souris, Marc

    2012-10-24

    Influenza is one of the most important leading causes of respiratory illness in the countries located in the tropical areas of South East Asia and Thailand. In this study the climate factors associated with influenza incidence in Chiang Mai Province, Northern Thailand, were investigated. Identification of factors responsible for influenza outbreaks and the mapping of potential risk areas in Chiang Mai are long overdue. This work examines the association between yearly climate patterns between 2001 and 2008 and influenza outbreaks in the Chiang Mai Province. The climatic factors included the amount of rainfall, percent of rainy days, relative humidity, maximum, minimum temperatures and temperature difference. The study develops a statistical analysis to quantitatively assess the relationship between climate and influenza outbreaks and then evaluate its suitability for predicting influenza outbreaks. A multiple linear regression technique was used to fit the statistical model. The Inverse Distance Weighted (IDW) interpolation and Geographic Information System (GIS) techniques were used in mapping the spatial diffusion of influenza risk zones. The results show that there is a significance correlation between influenza outbreaks and climate factors for the majority of the studied area. A statistical analysis was conducted to assess the validity of the model comparing model outputs and actual outbreaks.

  8. Factors affecting the results of comprehensive pre-internship exam among medical students of Kermanshah University of Medical Sciences.

    PubMed

    Khazaei, Mohammad Rasool; Zarin, Afshin; Rezaei, Mansuor; Khazaei, Mozafar

    2018-06-01

    This study was aimed to evaluate the factors affecting the results of comprehensive pre-internship exam (CPIE) among medicals students of Kermanshah University of Medical Sciences. In this descriptive-analytical study, all students (n=240) participating in CPIE over a 3-year period (2012-2014) were selected. Data were gathered by a questionnaire, including the CPIE results and educational and demographic data. Spearman correlation coefficient, Mann-Whitney U-test, and analysis of variance were used to analyze the association of students' success with study variables. Also, regression analysis was applied to determine the role of independent variables in students' success. The frequency of the failed units in apprenticeship course was one of the most important risk factors associated with failure in CPIE. Average scores of pre-internship course were the most important factors of success in CPIE. The CPIE score had the highest direct relationship with grade point average (GPA) of apprenticeship course, total GPA of all three courses, GPAs of physiopathology and basic sciences courses, and score of comprehensive basic sciences examination, respectively. CPIE showed the highest inverse correlation with the number of failed units in apprenticeship course. The most important factors influencing this exam were failure in apprenticeship course and GPA of previous educational stages.

  9. Classifying the Sizes of Explosive Eruptions using Tephra Deposits: The Advantages of a Numerical Inversion Approach

    NASA Astrophysics Data System (ADS)

    Connor, C.; Connor, L.; White, J.

    2015-12-01

    Explosive volcanic eruptions are often classified by deposit mass and eruption column height. How well are these eruption parameters determined in older deposits, and how well can we reduce uncertainty using robust numerical and statistical methods? We describe an efficient and effective inversion and uncertainty quantification approach for estimating eruption parameters given a dataset of tephra deposit thickness and granulometry. The inversion and uncertainty quantification is implemented using the open-source PEST++ code. Inversion with PEST++ can be used with a variety of forward models and here is applied using Tephra2, a code that simulates advective and dispersive tephra transport and deposition. The Levenburg-Marquardt algorithm is combined with formal Tikhonov and subspace regularization to invert eruption parameters; a linear equation for conditional uncertainty propagation is used to estimate posterior parameter uncertainty. Both the inversion and uncertainty analysis support simultaneous analysis of the full eruption and wind-field parameterization. The combined inversion/uncertainty-quantification approach is applied to the 1992 eruption of Cerro Negro (Nicaragua), the 2011 Kirishima-Shinmoedake (Japan), and the 1913 Colima (Mexico) eruptions. These examples show that although eruption mass uncertainty is reduced by inversion against tephra isomass data, considerable uncertainty remains for many eruption and wind-field parameters, such as eruption column height. Supplementing the inversion dataset with tephra granulometry data is shown to further reduce the uncertainty of most eruption and wind-field parameters. We think the use of such robust models provides a better understanding of uncertainty in eruption parameters, and hence eruption classification, than is possible with more qualitative methods that are widely used.

  10. Model-based assist feature insertion for sub-40nm memory device

    NASA Astrophysics Data System (ADS)

    Suh, Sungsoo; Lee, Suk-joo; Choi, Seong-woon; Lee, Sung-Woo; Park, Chan-hoon

    2009-04-01

    Many issues need to be resolved for a production-worthy model based assist feature insertion flow for single and double exposure patterning process to extend low k1 process at 193 nm immersion technology. Model based assist feature insertion is not trivial to implement either for single and double exposure patterning compared to rule based methods. As shown in Fig. 1, pixel based mask inversion technology in itself has difficulties in mask writing and inspection although it presents as one of key technology to extend single exposure for contact layer. Thus far, inversion technology is tried as a cooptimization of target mask to simultaneously generate optimized main and sub-resolution assists features for a desired process window. Alternatively, its technology can also be used to optimize for a target feature after an assist feature types are inserted in order to simplify the mask complexity. Simplification of inversion mask is one of major issue with applying inversion technology to device development even if a smaller mask feature can be fabricated since the mask writing time is also a major factor. As shown in Figure 2, mask writing time may be a limiting factor in determining whether or not an inversion solution is viable. It can be reasoned that increased number of shot counts relates to increase in margin for inversion methodology. On the other hand, there is a limit on how complex a mask can be in order to be production worthy. There is also source and mask co-optimization which influences the final mask patterns and assist feature sizes and positions for a given target. In this study, we will discuss assist feature insertion methods for sub 40-nm technology.

  11. A common 16p11.2 inversion underlies the joint susceptibility to asthma and obesity.

    PubMed

    González, Juan R; Cáceres, Alejandro; Esko, Tonu; Cuscó, Ivon; Puig, Marta; Esnaola, Mikel; Reina, Judith; Siroux, Valerie; Bouzigon, Emmanuelle; Nadif, Rachel; Reinmaa, Eva; Milani, Lili; Bustamante, Mariona; Jarvis, Deborah; Antó, Josep M; Sunyer, Jordi; Demenais, Florence; Kogevinas, Manolis; Metspalu, Andres; Cáceres, Mario; Pérez-Jurado, Luis A

    2014-03-06

    The prevalence of asthma and obesity is increasing worldwide, and obesity is a well-documented risk factor for asthma. The mechanisms underlying this association and parallel time trends remain largely unknown but genetic factors may be involved. Here, we report on a common ~0.45 Mb genomic inversion at 16p11.2 that can be accurately genotyped via SNP array data. We show that the inversion allele protects against the joint occurrence of asthma and obesity in five large independent studies (combined sample size of 317 cases and 543 controls drawn from a total of 5,809 samples; combined OR = 0.48, p = 5.5 × 10(-6)). Allele frequencies show remarkable worldwide population stratification, ranging from 10% in East Africa to 49% in Northern Europe, consistent with discordant and extreme genetic drifts or adaptive selections after human migration out of Africa. Inversion alleles strongly correlate with expression levels of neighboring genes, especially TUFM (p = 3.0 × 10(-40)) that encodes a mitochondrial protein regulator of energy balance and inhibitor of type 1 interferon, and other candidates for asthma (IL27) and obesity (APOB48R and SH2B1). Therefore, by affecting gene expression, the ~0.45 Mb 16p11.2 inversion provides a genetic basis for the joint susceptibility to asthma and obesity, with a population attributable risk of 39.7%. Differential mitochondrial function and basal energy balance of inversion alleles might also underlie the potential selection signature that led to their uneven distribution in world populations. Copyright © 2014 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  12. Distribution of genetic diversity in relation to chromosomal inversions in the malaria mosquito Anopheles gambiae.

    PubMed

    Mathiopoulos, K D; Lanzaro, G C

    1995-06-01

    The epidemiology of malaria in Africa is complicated by the fact that its principal vector, the mosquito Anopheles gambiae, constitutes a complex of six sibling species. Each species is characterized by a unique array of paracentric inversions, as deduced by karyotypic analysis. In addition, most of the species carry a number of polymorphic inversions. In order to develop an understanding of the evolutionary histories of different parts of the genome, we compared the genetic variation of areas inside and outside inversions in two distinct inversion karyotypes of A. gambiae. Thirty-five cDNA clones were mapped on the five arms of the A. gambiae chromosomes with divisional probes. Sixteen of these clones, localized both inside and outside inversions of chromosome 2, were used as probes in order to determine the nucleotide diversity of different parts of the genome in the two inversion karyotypes. We observed that the sequence diversity inside the inversion is more than three-fold lower than in areas outside the inversion and that the degree of divergence increases gradually at loci at increasing distance from the inversion. To interpret the data we present a selectionist and a stochastic model, both of which point to a relatively recent origin of the studied inversion and may suggest differences between the evolutionary history of inversions in Anopheles and Drosophila species.

  13. 3-dimensional magnetotelluric inversion including topography using deformed hexahedral edge finite elements and direct solvers parallelized on symmetric multiprocessor computers - Part II: direct data-space inverse solution

    NASA Astrophysics Data System (ADS)

    Kordy, M.; Wannamaker, P.; Maris, V.; Cherkaev, E.; Hill, G.

    2016-01-01

    Following the creation described in Part I of a deformable edge finite-element simulator for 3-D magnetotelluric (MT) responses using direct solvers, in Part II we develop an algorithm named HexMT for 3-D regularized inversion of MT data including topography. Direct solvers parallelized on large-RAM, symmetric multiprocessor (SMP) workstations are used also for the Gauss-Newton model update. By exploiting the data-space approach, the computational cost of the model update becomes much less in both time and computer memory than the cost of the forward simulation. In order to regularize using the second norm of the gradient, we factor the matrix related to the regularization term and apply its inverse to the Jacobian, which is done using the MKL PARDISO library. For dense matrix multiplication and factorization related to the model update, we use the PLASMA library which shows very good scalability across processor cores. A synthetic test inversion using a simple hill model shows that including topography can be important; in this case depression of the electric field by the hill can cause false conductors at depth or mask the presence of resistive structure. With a simple model of two buried bricks, a uniform spatial weighting for the norm of model smoothing recovered more accurate locations for the tomographic images compared to weightings which were a function of parameter Jacobians. We implement joint inversion for static distortion matrices tested using the Dublin secret model 2, for which we are able to reduce nRMS to ˜1.1 while avoiding oscillatory convergence. Finally we test the code on field data by inverting full impedance and tipper MT responses collected around Mount St Helens in the Cascade volcanic chain. Among several prominent structures, the north-south trending, eruption-controlling shear zone is clearly imaged in the inversion.

  14. Modeling analysis of pulsed magnetization process of magnetic core based on inverse Jiles-Atherton model

    NASA Astrophysics Data System (ADS)

    Liu, Yi; Zhang, He; Liu, Siwei; Lin, Fuchang

    2018-05-01

    The J-A (Jiles-Atherton) model is widely used to describe the magnetization characteristics of magnetic cores in a low-frequency alternating field. However, this model is deficient in the quantitative analysis of the eddy current loss and residual loss in a high-frequency magnetic field. Based on the decomposition of magnetization intensity, an inverse J-A model is established which uses magnetic flux density B as an input variable. Static and dynamic core losses under high frequency excitation are separated based on the inverse J-A model. Optimized parameters of the inverse J-A model are obtained based on particle swarm optimization. The platform for the pulsed magnetization characteristic test is designed and constructed. The hysteresis curves of ferrite and Fe-based nanocrystalline cores at high magnetization rates are measured. The simulated and measured hysteresis curves are presented and compared. It is found that the inverse J-A model can be used to describe the magnetization characteristics at high magnetization rates and to separate the static loss and dynamic loss accurately.

  15. Accounting for uncertain fault geometry in earthquake source inversions - I: theory and simplified application

    NASA Astrophysics Data System (ADS)

    Ragon, Théa; Sladen, Anthony; Simons, Mark

    2018-05-01

    The ill-posed nature of earthquake source estimation derives from several factors including the quality and quantity of available observations and the fidelity of our forward theory. Observational errors are usually accounted for in the inversion process. Epistemic errors, which stem from our simplified description of the forward problem, are rarely dealt with despite their potential to bias the estimate of a source model. In this study, we explore the impact of uncertainties related to the choice of a fault geometry in source inversion problems. The geometry of a fault structure is generally reduced to a set of parameters, such as position, strike and dip, for one or a few planar fault segments. While some of these parameters can be solved for, more often they are fixed to an uncertain value. We propose a practical framework to address this limitation by following a previously implemented method exploring the impact of uncertainties on the elastic properties of our models. We develop a sensitivity analysis to small perturbations of fault dip and position. The uncertainties in fault geometry are included in the inverse problem under the formulation of the misfit covariance matrix that combines both prediction and observation uncertainties. We validate this approach with the simplified case of a fault that extends infinitely along strike, using both Bayesian and optimization formulations of a static inversion. If epistemic errors are ignored, predictions are overconfident in the data and source parameters are not reliably estimated. In contrast, inclusion of uncertainties in fault geometry allows us to infer a robust posterior source model. Epistemic uncertainties can be many orders of magnitude larger than observational errors for great earthquakes (Mw > 8). Not accounting for uncertainties in fault geometry may partly explain observed shallow slip deficits for continental earthquakes. Similarly, ignoring the impact of epistemic errors can also bias estimates of near surface slip and predictions of tsunamis induced by megathrust earthquakes. (Mw > 8)

  16. Factors Associated with Recurrent Suicidal Ideation among Racially and Ethnically Diverse College Students with a History of Suicide Attempt: The Role of Mindfulness.

    PubMed

    Chesin, Megan S; Jeglic, Elizabeth L

    2016-01-01

    Although one-third of enrolled U.S. undergraduate college students are non-White, little is known about risk factors for suicidal behavior among racial and ethnic minority students. Thus, we set out to determine psychosocial factors associated with recurrent suicidal ideation among racially and ethnically diverse college students with a history of suicide attempt. From 2012-2013, 1,734 racially and ethnically diverse college students completed an on-line survey of suicidal behavior and associated factors. Depression, hopelessness, rejection sensitivity, and mindfulness, as well as past-year discrimination, ethnic identification, and acculturative stress were measured using well-validated self-report instruments. The Beck Scale for Suicide Ideation was used to assess current suicidal ideation. A subsample of 118 college students who self-reported a past suicide attempt were selected for the current analysis. Logistic regression analysis was used to test associations between risk factors and the presence of suicidal ideation, and linear regression analysis was used to test factors associated with suicidal ideation severity among those who reported current suicidal ideation. Depression was significantly related to both the presence and severity of current suicidal ideation. Mindfulness, and in particular awareness of present moment experience, was also inversely associated with ideation severity. We found depression and mindlessness were associated with suicidal ideation severity among a sample of diverse college students at high risk for suicidal behavior due to a past suicide attempt. Factors unique to the minority experience, such as acculturative stress, were not associated with current suicidal ideation. Implications for suicide prevention are discussed.

  17. Estimating soil hydraulic parameters from transient flow experiments in a centrifuge using parameter optimization technique

    USGS Publications Warehouse

    Šimůnek, Jirka; Nimmo, John R.

    2005-01-01

    A modified version of the Hydrus software package that can directly or inversely simulate water flow in a transient centrifugal field is presented. The inverse solver for parameter estimation of the soil hydraulic parameters is then applied to multirotation transient flow experiments in a centrifuge. Using time‐variable water contents measured at a sequence of several rotation speeds, soil hydraulic properties were successfully estimated by numerical inversion of transient experiments. The inverse method was then evaluated by comparing estimated soil hydraulic properties with those determined independently using an equilibrium analysis. The optimized soil hydraulic properties compared well with those determined using equilibrium analysis and steady state experiment. Multirotation experiments in a centrifuge not only offer significant time savings by accelerating time but also provide significantly more information for the parameter estimation procedure compared to multistep outflow experiments in a gravitational field.

  18. Assimilating data into open ocean tidal models

    NASA Astrophysics Data System (ADS)

    Kivman, Gennady A.

    The problem of deriving tidal fields from observations by reason of incompleteness and imperfectness of every data set practically available has an infinitely large number of allowable solutions fitting the data within measurement errors and hence can be treated as ill-posed. Therefore, interpolating the data always relies on some a priori assumptions concerning the tides, which provide a rule of sampling or, in other words, a regularization of the ill-posed problem. Data assimilation procedures used in large scale tide modeling are viewed in a common mathematical framework as such regularizations. It is shown that they all (basis functions expansion, parameter estimation, nudging, objective analysis, general inversion, and extended general inversion), including those (objective analysis and general inversion) originally formulated in stochastic terms, may be considered as utilizations of one of the three general methods suggested by the theory of ill-posed problems. The problem of grid refinement critical for inverse methods and nudging is discussed.

  19. A sparse reconstruction method for the estimation of multi-resolution emission fields via atmospheric inversion

    DOE PAGES

    Ray, J.; Lee, J.; Yadav, V.; ...

    2015-04-29

    Atmospheric inversions are frequently used to estimate fluxes of atmospheric greenhouse gases (e.g., biospheric CO 2 flux fields) at Earth's surface. These inversions typically assume that flux departures from a prior model are spatially smoothly varying, which are then modeled using a multi-variate Gaussian. When the field being estimated is spatially rough, multi-variate Gaussian models are difficult to construct and a wavelet-based field model may be more suitable. Unfortunately, such models are very high dimensional and are most conveniently used when the estimation method can simultaneously perform data-driven model simplification (removal of model parameters that cannot be reliably estimated) andmore » fitting. Such sparse reconstruction methods are typically not used in atmospheric inversions. In this work, we devise a sparse reconstruction method, and illustrate it in an idealized atmospheric inversion problem for the estimation of fossil fuel CO 2 (ffCO 2) emissions in the lower 48 states of the USA. Our new method is based on stagewise orthogonal matching pursuit (StOMP), a method used to reconstruct compressively sensed images. Our adaptations bestow three properties to the sparse reconstruction procedure which are useful in atmospheric inversions. We have modified StOMP to incorporate prior information on the emission field being estimated and to enforce non-negativity on the estimated field. Finally, though based on wavelets, our method allows for the estimation of fields in non-rectangular geometries, e.g., emission fields inside geographical and political boundaries. Our idealized inversions use a recently developed multi-resolution (i.e., wavelet-based) random field model developed for ffCO 2 emissions and synthetic observations of ffCO 2 concentrations from a limited set of measurement sites. We find that our method for limiting the estimated field within an irregularly shaped region is about a factor of 10 faster than conventional approaches. It also reduces the overall computational cost by a factor of 2. Further, the sparse reconstruction scheme imposes non-negativity without introducing strong nonlinearities, such as those introduced by employing log-transformed fields, and thus reaps the benefits of simplicity and computational speed that are characteristic of linear inverse problems.« less

  20. A sparse reconstruction method for the estimation of multi-resolution emission fields via atmospheric inversion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ray, J.; Lee, J.; Yadav, V.

    Atmospheric inversions are frequently used to estimate fluxes of atmospheric greenhouse gases (e.g., biospheric CO 2 flux fields) at Earth's surface. These inversions typically assume that flux departures from a prior model are spatially smoothly varying, which are then modeled using a multi-variate Gaussian. When the field being estimated is spatially rough, multi-variate Gaussian models are difficult to construct and a wavelet-based field model may be more suitable. Unfortunately, such models are very high dimensional and are most conveniently used when the estimation method can simultaneously perform data-driven model simplification (removal of model parameters that cannot be reliably estimated) andmore » fitting. Such sparse reconstruction methods are typically not used in atmospheric inversions. In this work, we devise a sparse reconstruction method, and illustrate it in an idealized atmospheric inversion problem for the estimation of fossil fuel CO 2 (ffCO 2) emissions in the lower 48 states of the USA. Our new method is based on stagewise orthogonal matching pursuit (StOMP), a method used to reconstruct compressively sensed images. Our adaptations bestow three properties to the sparse reconstruction procedure which are useful in atmospheric inversions. We have modified StOMP to incorporate prior information on the emission field being estimated and to enforce non-negativity on the estimated field. Finally, though based on wavelets, our method allows for the estimation of fields in non-rectangular geometries, e.g., emission fields inside geographical and political boundaries. Our idealized inversions use a recently developed multi-resolution (i.e., wavelet-based) random field model developed for ffCO 2 emissions and synthetic observations of ffCO 2 concentrations from a limited set of measurement sites. We find that our method for limiting the estimated field within an irregularly shaped region is about a factor of 10 faster than conventional approaches. It also reduces the overall computational cost by a factor of 2. Further, the sparse reconstruction scheme imposes non-negativity without introducing strong nonlinearities, such as those introduced by employing log-transformed fields, and thus reaps the benefits of simplicity and computational speed that are characteristic of linear inverse problems.« less

  1. Variational methods for direct/inverse problems of atmospheric dynamics and chemistry

    NASA Astrophysics Data System (ADS)

    Penenko, Vladimir; Penenko, Alexey; Tsvetova, Elena

    2013-04-01

    We present a variational approach for solving direct and inverse problems of atmospheric hydrodynamics and chemistry. It is important that the accurate matching of numerical schemes has to be provided in the chain of objects: direct/adjoint problems - sensitivity relations - inverse problems, including assimilation of all available measurement data. To solve the problems we have developed a new enhanced set of cost-effective algorithms. The matched description of the multi-scale processes is provided by a specific choice of the variational principle functionals for the whole set of integrated models. Then all functionals of variational principle are approximated in space and time by splitting and decomposition methods. Such approach allows us to separately consider, for example, the space-time problems of atmospheric chemistry in the frames of decomposition schemes for the integral identity sum analogs of the variational principle at each time step and in each of 3D finite-volumes. To enhance the realization efficiency, the set of chemical reactions is divided on the subsets related to the operators of production and destruction. Then the idea of the Euler's integrating factors is applied in the frames of the local adjoint problem technique [1]-[3]. The analytical solutions of such adjoint problems play the role of integrating factors for differential equations describing atmospheric chemistry. With their help, the system of differential equations is transformed to the equivalent system of integral equations. As a result we avoid the construction and inversion of preconditioning operators containing the Jacobi matrixes which arise in traditional implicit schemes for ODE solution. This is the main advantage of our schemes. At the same time step but on the different stages of the "global" splitting scheme, the system of atmospheric dynamic equations is solved. For convection - diffusion equations for all state functions in the integrated models we have developed the monotone and stable discrete-analytical numerical schemes [1]-[3] conserving the positivity of the chemical substance concentrations and possessing the properties of energy and mass balance that are postulated in the general variational principle for integrated models. All algorithms for solution of transport, diffusion and transformation problems are direct (without iterations). The work is partially supported by the Programs No 4 of Presidium RAS and No 3 of Mathematical Department of RAS, by RFBR project 11-01-00187 and Integrating projects of SD RAS No 8 and 35. Our studies are in the line with the goals of COST Action ES1004. References Penenko V., Tsvetova E. Discrete-analytical methods for the implementation of variational principles in environmental applications// Journal of computational and applied mathematics, 2009, v. 226, 319-330. Penenko A.V. Discrete-analytic schemes for solving an inverse coefficient heat conduction problem in a layered medium with gradient methods// Numerical Analysis and Applications, 2012, V. 5, pp 326-341. V. Penenko, E. Tsvetova. Variational methods for constructing the monotone approximations for atmospheric chemistry models //Numerical Analysis and Applications, 2013 (in press).

  2. The Association Between Fog and Temperature Inversions from Ground and Radiosonde Observations in East Greenland

    NASA Astrophysics Data System (ADS)

    Gilson, G.; Jiskoot, H.

    2016-12-01

    Many Arctic glaciers terminate along coasts where temperature inversions and sea fog are frequent during summer. Both can influence glacier ablation, but the effects of fog may be complex. To understand fog's physical and radiative properties and its association to temperature inversions it is important to determine accurate Arctic coastal fog climatologies In previous research we determined that fog in East Greenland peaks in the melt season and can be spatially extensive over glacierized terrain. In this study we aim to understand which environmental factors influence fog occurrence in East Greenland; understand the association between fog and temperature inversions; and quantify fog height. We analyzed fog observations and other weather data from coastal synoptic weather stations, and extracted temperature inversions from the Integrated Global Radiosonde Archive radiosonde profiles. Fog height was calculated from radiosonde profiles, based on a method developed for radiation fog which we expanded to include advection and steam fog. Our results show that Arctic coastal fog requires sea ice breakup and a sea breeze with wind speed between 1-4 m/s. Fog is mostly advective, occurring under stable synoptic conditions characterized by deep and strong low-level temperature inversions. Steam fog may occur 5-30% of the time. Fog can occur under near-surface subsidence, with a subsaturated inversion base, or a saturated inversion base. We classified five types of fog based on their vertical sounding characteristics: only at the surface, below an inversion, capped by an inversion, inside a surface-based inversion, or inside a low-level inversion. Fog is commonly 100-400 m thick, often reaching the top of the boundary layer. Fog height is greater at northern stations, where daily fog duration is longer and relative humidity lower. Our results will be included in glacier energy-balance models to account for the influence of fog and temperature inversions on glacier melt.

  3. Failure to unmask pseudonormal diastolic function by a valsalva maneuver: tricuspid insufficiency is a major factor.

    PubMed

    Hu, Kai; Liu, Dan; Niemann, Markus; Hatle, Liv; Herrmann, Sebastian; Voelker, Wolfram; Ertl, Georg; Bijnens, Bart; Weidemann, Frank

    2011-11-01

    For the clinical assessment of patients with dyspnea, the inversion of the early (E) and late (A) transmitral flow during Valsalva maneuver (VM) frequently helps to distinguish pseudonormal from normal filling pattern. However, in an important number of patients, VM fails to reveal the change from dominant early mitral flow velocity toward larger late velocity. From December 2009 to October 2010, we selected consecutive patients with abnormal filling with (n=25) and without E/A inversion (n=25) during VM. Transmitral, tricuspid, and pulmonary Doppler traces were recorded and the degree of insufficiency was estimated. After evaluating all standard echocardiographic morphological, functional, and flow-related parameters, it became evident that the failure to unmask the pseudonormal filling pattern by VM was related to the degree of the tricuspid insufficiency (TI). TI was graded as mild in 24 of 25 patients in the group with E/A inversion during VM, whereas TI was graded as moderate to severe in 24 of the 25 patients with pseudonormal diastolic function without E/A inversion during VM. Our data suggest that TI is a major factor to prevent E/A inversion during a VM in patients with pseudonormal diastolic function. This probably is due to a decrease in TI resulting in an increase in forward flow rather than the expected decrease during the VM. Thus, whenever a pseudonormal diastolic filling pattern is suspected, the use of a VM is not an informative discriminator in the presence of moderate or severe TI.

  4. Unmanned Systems: A Lab Based Robotic Arm for Grasping Phase II

    DTIC Science & Technology

    2016-12-01

    Leap Motion Controller, inverse kinematics, DH parameters. 15. NUMBER OF PAGES 89 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT...robotic actuator. Inverse kinematics and Denavit-Hartenberg (DH) parameters will be briefly explained. A. POSITION ANALYSIS According to [3] and... inverse kinematic” method and allows us to calculate the actuator’s position in order to move the robot’s end effector to a specific point in space

  5. Fruit and vegetables consumption and incident hypertension: dose-response meta-analysis of prospective cohort studies.

    PubMed

    Wu, L; Sun, D; He, Y

    2016-10-01

    The role of dietary factors on chronic diseases seems essential in the potentially adverse or preventive effects. However, no evidence of dose-response meta-analysis of prospective cohort studies has verified the association between the intake of fruit and/or vegetables and the risk of developing hypertension. The PubMed and Embase were searched for prospective cohort studies. A generic inverse-variance method with random effects model was used to calculate the pooled relative risks (RRs) and 95% confidence intervals (CIs). Generalized least squares trend estimation model was used to calculate the study-specific slopes for the dose-response analyses. Seven articles comprised nine cohorts involving 185 676 participants were assessed. The highest intake of fruit or vegetables separately, and total fruit and vegetables were inversely associated with the incident risk of hypertension compared with the lowest level, and the pooled RRs and 95% CIs were 0.87 (0.79, 0.95), 0.88 (0.79, 0.99) and 0.90 (0.84, 0.98), respectively. We also found an inverse dose-response relation between the risk of developing hypertension and fruit intake, and total fruit and vegetables consumption. The incident risk of hypertension was decreased by 1.9% for each serving per day of fruit consumption, and decreased by 1.2% for each serving per day of total fruit and vegetables consumption. Our results support the recommendation to increase the consumption of fruit and vegetables with respect to preventing the risk of developing hypertension. However, further large prospective studies and long-term high-quality randomized controlled trials are still needed to confirm the observed association.

  6. Weighting by Inverse Variance or by Sample Size in Random-Effects Meta-Analysis

    ERIC Educational Resources Information Center

    Marin-Martinez, Fulgencio; Sanchez-Meca, Julio

    2010-01-01

    Most of the statistical procedures in meta-analysis are based on the estimation of average effect sizes from a set of primary studies. The optimal weight for averaging a set of independent effect sizes is the inverse variance of each effect size, but in practice these weights have to be estimated, being affected by sampling error. When assuming a…

  7. Apparatus and system for multivariate spectral analysis

    DOEpatents

    Keenan, Michael R.; Kotula, Paul G.

    2003-06-24

    An apparatus and system for determining the properties of a sample from measured spectral data collected from the sample by performing a method of multivariate spectral analysis. The method can include: generating a two-dimensional matrix A containing measured spectral data; providing a weighted spectral data matrix D by performing a weighting operation on matrix A; factoring D into the product of two matrices, C and S.sup.T, by performing a constrained alternating least-squares analysis of D=CS.sup.T, where C is a concentration intensity matrix and S is a spectral shapes matrix; unweighting C and S by applying the inverse of the weighting used previously; and determining the properties of the sample by inspecting C and S. This method can be used by a spectrum analyzer to process X-ray spectral data generated by a spectral analysis system that can include a Scanning Electron Microscope (SEM) with an Energy Dispersive Detector and Pulse Height Analyzer.

  8. Allergies and Risk of Head and Neck Cancer: An Original Study plus Meta-Analysis

    PubMed Central

    Lo, Hung-I; Huang, Cheng-Chih; Lee, Wei-Ting; Huang, Jehn-Shyun; Chen, Ken-Chung; Wong, Tung-Yiu; Tsai, Sen-Tien; Yen, Chia-Jui; Wu, Yuan-Hua; Hsueh, Wei-Ting; Yang, Ming-Wei; Wu, Shang-Yin; Chang, Jang-Yang; Chang, Kwang-Yu; Lin, Chen-Lin; Wang, Fang-Ting; Wang, Yi-Hui; Weng, Ya-Ling; Yang, Han-Chien; Chang, Jeffrey S.

    2013-01-01

    Background Although the relationship between allergy and cancer has been investigated extensively, the role of allergy in head and neck cancer (HNC) appears less consistent. It is not clear whether allergies can independently influence the risk of HNC in the presence of known strong environmental risk factors, including consumption of alcohol, betel quid, and cigarette. Methods The current paper reports results from: 1) an original hospital-based case-control study, which included 252 incident cases of HNC and 236 controls frequency-matched to cases on sex and age; and 2) a meta-analysis combining the results of the current case-control study and 13 previously published studies (9 cohort studies with 727,569 subjects and 550 HNC outcomes and 5 case-control studies with 4,017 HNC cases and 10,928 controls). Results In the original case-control study, we observed a strong inverse association between allergies and HNC [odds ratio = 0.41, 95% confidence interval (CI): 0.27–0.62]. The meta-analysis also indicated a statistically significant inverse association between HNC and allergies [meta-relative risk (RR) = 0.76, 95% CI: 0.63–0.91], particularly strong for allergic rhinitis (meta-RR = 0.55, 95% CI: 0.40–0.76). In addition, the inverse association between allergies and HNC was observed only among men (meta-RR = 0.67, 95% CI: 0.54–0.84) but not among women (meta-RR = 0.98, 95% CI: 0.81–1.18). Conclusions These findings suggest that immunity plays an influential role in the risk of HNC. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are warranted to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help devise effective strategies to reduce and treat HNC. PMID:23383309

  9. Computer Model Inversion and Uncertainty Quantification in the Geosciences

    NASA Astrophysics Data System (ADS)

    White, Jeremy T.

    The subject of this dissertation is use of computer models as data analysis tools in several different geoscience settings, including integrated surface water/groundwater modeling, tephra fallout modeling, geophysical inversion, and hydrothermal groundwater modeling. The dissertation is organized into three chapters, which correspond to three individual publication manuscripts. In the first chapter, a linear framework is developed to identify and estimate the potential predictive consequences of using a simple computer model as a data analysis tool. The framework is applied to a complex integrated surface-water/groundwater numerical model with thousands of parameters. Several types of predictions are evaluated, including particle travel time and surface-water/groundwater exchange volume. The analysis suggests that model simplifications have the potential to corrupt many types of predictions. The implementation of the inversion, including how the objective function is formulated, what minimum of the objective function value is acceptable, and how expert knowledge is enforced on parameters, can greatly influence the manifestation of model simplification. Depending on the prediction, failure to specifically address each of these important issues during inversion is shown to degrade the reliability of some predictions. In some instances, inversion is shown to increase, rather than decrease, the uncertainty of a prediction, which defeats the purpose of using a model as a data analysis tool. In the second chapter, an efficient inversion and uncertainty quantification approach is applied to a computer model of volcanic tephra transport and deposition. The computer model simulates many physical processes related to tephra transport and fallout. The utility of the approach is demonstrated for two eruption events. In both cases, the importance of uncertainty quantification is highlighted by exposing the variability in the conditioning provided by the observations used for inversion. The worth of different types of tephra data to reduce parameter uncertainty is evaluated, as is the importance of different observation error models. The analyses reveal the importance using tephra granulometry data for inversion, which results in reduced uncertainty for most eruption parameters. In the third chapter, geophysical inversion is combined with hydrothermal modeling to evaluate the enthalpy of an undeveloped geothermal resource in a pull-apart basin located in southeastern Armenia. A high-dimensional gravity inversion is used to define the depth to the contact between the lower-density valley fill sediments and the higher-density surrounding host rock. The inverted basin depth distribution was used to define the hydrostratigraphy for the coupled groundwater-flow and heat-transport model that simulates the circulation of hydrothermal fluids in the system. Evaluation of several different geothermal system configurations indicates that the most likely system configuration is a low-enthalpy, liquid-dominated geothermal system.

  10. Psychosocial and Demographic Correlates of Employment versus Disability Status in a National Community Sample of Adults with Chronic Pain: Toward a Psychology of Pain Presenteeism

    PubMed Central

    Karoly, Paul; Ruehlman, Linda S.; Okun, Morris A.

    2013-01-01

    Background Although chronic pain is a source of work-related disability, relatively little research has addressed the psychological factors that differentiate individuals in chronic pain who leave the workforce from those who remain on the job despite their pain. Objective The present study examined a small set of attitudinal and coping-related factors as potential correlates of pain-related disability versus continued part- or full time employment over and above the role of well-known risk factors. Methods A large sample of adult men and women with chronic pain drawn from across the United States (N= 1293) by means of random digit dialing was subdivided into two groups: working (N = 859) and on disability (N = 434). Both groups were interviewed (by telephone) to complete a set of instruments (called the Profile of Chronic Pain: Extended Assessment [PCP: EA] Battery) measuring pain attitudes and coping methods. Results Logistic regression analysis revealed, as expected, that continued employment status was inversely related to pain severity and work status was positively related to higher education and being Hispanic. After controlling for severity and demographic factors, belief in a medical cure and catastrophizing tendencies were significant inverse predictors and task persistence was a positive predictor of continued employment. Conclusions Results revealed both demographic and attitudinal predictors of continued employment, and highlight the value of harnessing insights from the psychology of work engagement to better understand the processes underlying pain presenteeism. Interventions designed to keep persons with pain in the active work force should build upon and extend the present findings. PMID:24010682

  11. Medical history, lifestyle, family history, and occupational risk factors for sporadic Burkitt lymphoma/leukemia: the Interlymph Non-Hodgkin Lymphoma Subtypes Project.

    PubMed

    Mbulaiteye, Sam M; Morton, Lindsay M; Sampson, Joshua N; Chang, Ellen T; Costas, Laura; de Sanjosé, Silvia; Lightfoot, Tracy; Kelly, Jennifer; Friedberg, Jonathan W; Cozen, Wendy; Marcos-Gragera, Rafael; Slager, Susan L; Birmann, Brenda M; Weisenburger, Dennis D

    2014-08-01

    The etiologic role of medical history, lifestyle, family history, and occupational risk factors in sporadic Burkitt lymphoma (BL) is unknown, but epidemiologic and clinical evidence suggests that risk factors may vary by age. We investigated risk factors for sporadic BL in 295 cases compared with 21818 controls in a pooled analysis of 18 case-control studies in the International Lymphoma Epidemiology Consortium (InterLymph). Cases were defined to include typical BL or Burkitt-like lymphoma. Odds ratios (ORs) and 95% confidence intervals (CIs) for associations were calculated separately for younger (<50 years) and older (≥ 50 years) BL using multivariate logistic regression. Cases included 133 younger BL and 159 older BL (age was missing for three cases) and they were evenly split between typical BL (n = 147) and Burkitt-like lymphoma (n = 148). BL in younger participants was inversely associated with a history of allergy (OR = 0.58; 95% CI = 0.32 to 1.05), and positively associated with a history of eczema among individuals without other atopic conditions (OR = 2.54; 95% CI = 1.20 to 5.40), taller height (OR = 2.17; 95% CI = 1.08 to 4.36), and employment as a cleaner (OR = 3.49; 95% CI = 1.13 to 10.7). BL in older participants was associated with a history of hepatitis C virus seropositivity (OR = 4.19; 95% CI = 1.05 to 16.6) based on three exposed cases. Regardless of age, BL was inversely associated with alcohol consumption and positively associated with height. Our data suggest that BL in younger and older adults may be etiologically distinct. Published by Oxford University Press 2014.

  12. Standardized uptake value and apparent diffusion coefficient of endometrial cancer evaluated with integrated whole-body PET/MR: Correlation with pathological prognostic factors.

    PubMed

    Shih, I-Lun; Yen, Ruoh-Fang; Chen, Chi-An; Chen, Bang-Bin; Wei, Shwu-Yuan; Chang, Wen-Chun; Sheu, Bor-Ching; Cheng, Wen-Fang; Tseng, Yao-Hui; Chen, Xin-Jia; Chen, Chi-Hau; Wei, Lin-Hung; Chiang, Ying-Cheng; Torng, Pao-Ling; Yen, Men-Luh; Shih, Tiffany Ting-Fang

    2015-12-01

    To evaluate the correlation between maximum standardized uptake value (SUVmax ) and minimum apparent diffusion coefficient (ADCmin ) of endometrial cancer derived from an integrated positron emission tomography / magnetic resonance (PET/MR) system and to determine their correlation with pathological prognostic factors. This prospective study was approved by the Institutional Review Board of the hospital, and informed consent was obtained. Between April and December 2014, 47 consecutive patients with endometrial cancer were enrolled and underwent simultaneous PET/MR examinations before surgery. Thirty-six patients with measurable tumors on PET/MR were included for image analysis. Pearson's correlation coefficient was used to evaluate the correlation between SUVmax and ADCmin of the tumors. The Mann-Whitney U-test was utilized to evaluate relationships between these two imaging biomarkers and pathological prognostic factors. The mean SUVmax and ADCmin were 14.7 ± 7.1 and 0.48 ± 0.13 × 10(-3) mm(2) /s, respectively. A significant inverse correlation was found between SUVmax and ADCmin (r = -0.53; P = 0.001). SUVmax was significantly higher in tumors with advanced stage, deep myometrial invasion, cervical invasion, lymphovascular space involvement, and lymph node metastasis (P < 0.05). ADCmin was lower in tumors with higher grade, advanced stage, and cervical invasion (P < 0.05). The ratio of SUVmax to ADCmin was higher in tumors with higher grade, advanced stage, deep myometrial invasion, cervical invasion, lymphovascular space involvement, and lymph node metastasis (P < 0.05). SUVmax and ADCmin of endometrial cancer derived from integrated PET/MR are inversely correlated and are associated with pathological prognostic factors. © 2015 Wiley Periodicals, Inc.

  13. Risk factors for colorectal cancer in subjects with family history of the disease.

    PubMed

    Fernandez, E; La Vecchia, C; D'Avanzo, B; Negri, E; Franceschi, S

    1997-01-01

    The relationship between lifestyle factors, past medical conditions, daily meal frequency, diet and the risk of 'familial' colorectal cancer has been analysed using data from a case-control study conducted in northern Italy. A total of 1584 colorectal cancer patients and 2879 control subjects were admitted to a network of hospitals in the Greater Milan area and the Pordenone province. The subjects included for analysis were the 112 cases and the 108 control subjects who reported a family history of colorectal cancer in first-degree relatives. Colorectal cancer cases and control subjects with family history were similarly distributed according to sex, age, marital status, years of schooling and social class. Familial colorectal cancer was associated with meal frequency, medical history of diabetes (relative risk, RR = 4.6) and cholelithiasis (RR = 5.2). Significant positive trends of increasing risk with more frequent consumption were observed for pasta (RR = 2.5, for the highest vs the lowest intake tertile), pastries (RR = 2.4), red meat (RR = 2.9), canned meat (RR = 1.9), cheese (RR = 3.5) and butter (RR = 1.9). Significant inverse associations and trends in risk were observed for consumption of poultry (RR = 0.4), tomatoes (RR = 0.2), peppers (RR = 0.3) and lettuce (RR = 0.3). Significant inverse trends in risk with increasing consumption for beta-carotene and ascorbic acid were observed (RR = 0.5 and 0.4 respectively, highest vs lowest intake tertile). These results suggest that risk factors for subjects with a family history of colorectal cancer in first-degree relatives are not appreciably different from recognized risk factors of the disease in the general population.

  14. Sub-Coulomb He 3 transfer and its use to extract three-particle asymptotic normalization coefficients

    DOE PAGES

    Avila, M. L.; Baby, L. T.; Belarge, J.; ...

    2018-01-22

    In this work, data for the 13C( 6Li,t) 16O reaction, obtained in inverse kinematics at a 13C incident energy of 7.72 MeV, are presented. A distorted wave Born approximation (DWBA) analysis was used to extract spectroscopic factors and asymptotic normalization coefficients (ANCs) for the < 16O | 13C + 3He> overlaps, subject to the assumption of a fixed < 6Li | 3He + 3H> overlap. The variation of the extracted spectroscopic factors and ANCs as a function of various inputs to the DWBA calculations was explored. The extracted ANCs were found to vary as a cubic function of the radiusmore » of the potential well binding the transferred 3He to the 13C core while the spectroscopic factors varied as a quartic function of the radius. Finally, the ANC values could be determined to within a factor of two for this system.« less

  15. Sub-Coulomb He 3 transfer and its use to extract three-particle asymptotic normalization coefficients

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Avila, M. L.; Baby, L. T.; Belarge, J.

    In this work, data for the 13C( 6Li,t) 16O reaction, obtained in inverse kinematics at a 13C incident energy of 7.72 MeV, are presented. A distorted wave Born approximation (DWBA) analysis was used to extract spectroscopic factors and asymptotic normalization coefficients (ANCs) for the < 16O | 13C + 3He> overlaps, subject to the assumption of a fixed < 6Li | 3He + 3H> overlap. The variation of the extracted spectroscopic factors and ANCs as a function of various inputs to the DWBA calculations was explored. The extracted ANCs were found to vary as a cubic function of the radiusmore » of the potential well binding the transferred 3He to the 13C core while the spectroscopic factors varied as a quartic function of the radius. Finally, the ANC values could be determined to within a factor of two for this system.« less

  16. Sub-Coulomb 3He transfer and its use to extract three-particle asymptotic normalization coefficients

    NASA Astrophysics Data System (ADS)

    Avila, M. L.; Baby, L. T.; Belarge, J.; Keeley, N.; Kemper, K. W.; Koshchiy, E.; Kuchera, A. N.; Rogachev, G. V.; Rusek, K.; Santiago-Gonzalez, D.

    2018-01-01

    Data for the 13C(6Li,t )16O reaction, obtained in inverse kinematics at a 13C incident energy of 7.72 MeV, are presented. A distorted wave Born approximation (DWBA) analysis was used to extract spectroscopic factors and asymptotic normalization coefficients (ANCs) for the 〈" close="〉6Li∣3He +3H 〉">16O∣13C +3He overlaps, subject to the assumption of a fixed [The influence of certain meteorological factors on mortality from complications of arterial hypertension].

    PubMed

    Afanas'eva, G N; Panova, T N; Dedova, A V; Dzhuvaliakov, P G

    2010-01-01

    The weather may influence the clinical course of many diseases. The objective of the present study was to evaluate effects of certain meteorological factors on the mortality rate associated with complications of arterial hypertension (cerebral stroke and myocardial infarction) in the city of Astrakhan during the period from 1983 to 2005. The analysis included 17,198 cases of death from cardiovascular disorders (CVD). An original software program was used for the purpose that made it possible to estimate the influence of meteorological factors (air temperature, velocity of wind and precipitation) on the mortality rate among subjects with and without AH. It was shown that mortality due to coronary heart disease (CHD) and cerebrovascular disease positively correlated with the air temperature and amount of precipitation but inversely correlated with the velocity of wind. Correlations between mortality from CVD and meteorological factors among subjects presenting with CHD, cerebrovascular disease, and AH were more pronounced and statistically significant compared with patients of the same groups without AH.

  17. High-resolution inversion of OMI formaldehyde columns to quantify isoprene emission on ecosystem-relevant scales: application to the southeast US

    NASA Astrophysics Data System (ADS)

    Kaiser, Jennifer; Jacob, Daniel J.; Zhu, Lei; Travis, Katherine R.; Fisher, Jenny A.; González Abad, Gonzalo; Zhang, Lin; Zhang, Xuesong; Fried, Alan; Crounse, John D.; St. Clair, Jason M.; Wisthaler, Armin

    2018-04-01

    Isoprene emissions from vegetation have a large effect on atmospheric chemistry and air quality. Bottom-up isoprene emission inventories used in atmospheric models are based on limited vegetation information and uncertain land cover data, leading to potentially large errors. Satellite observations of atmospheric formaldehyde (HCHO), a high-yield isoprene oxidation product, provide top-down information to evaluate isoprene emission inventories through inverse analyses. Past inverse analyses have however been hampered by uncertainty in the HCHO satellite data, uncertainty in the time- and NOx-dependent yield of HCHO from isoprene oxidation, and coarse resolution of the atmospheric models used for the inversion. Here we demonstrate the ability to use HCHO satellite data from OMI in a high-resolution inversion to constrain isoprene emissions on ecosystem-relevant scales. The inversion uses the adjoint of the GEOS-Chem chemical transport model at 0.25° × 0.3125° horizontal resolution to interpret observations over the southeast US in August-September 2013. It takes advantage of concurrent NASA SEAC4RS aircraft observations of isoprene and its oxidation products including HCHO to validate the OMI HCHO data over the region, test the GEOS-Chem isoprene oxidation mechanism and NOx environment, and independently evaluate the inversion. This evaluation shows in particular that local model errors in NOx concentrations propagate to biases in inferring isoprene emissions from HCHO data. It is thus essential to correct model NOx biases, which was done here using SEAC4RS observations but can be done more generally using satellite NO2 data concurrently with HCHO. We find in our inversion that isoprene emissions from the widely used MEGAN v2.1 inventory are biased high over the southeast US by 40 % on average, although the broad-scale distributions are correct including maximum emissions in Arkansas/Louisiana and high base emission factors in the oak-covered Ozarks of southeast Missouri. A particularly large discrepancy is in the Edwards Plateau of central Texas where MEGAN v2.1 is too high by a factor of 3, possibly reflecting errors in land cover. The lower isoprene emissions inferred from our inversion, when implemented into GEOS-Chem, decrease surface ozone over the southeast US by 1-3 ppb and decrease the isoprene contribution to organic aerosol from 40 to 20 %.

  18. Evaluation of Abortion Stigma in the Workforce: Development of the Revised Abortion Providers Stigma Scale.

    PubMed

    Martin, Lisa A; Hassinger, Jane A; Seewald, Meghan; Harris, Lisa H

    We report on the development of a scale measuring abortion providers' experiences of stigma. Using previous measures, qualitative data, and expert review, we created a 49-item question pool. We administered questions to 315 abortion providers before participation in the Providers Share Workshop. We explored the factor structure and item quality using exploratory factor analysis. We assessed reliability using Cronbach's alpha. To test construct validity, we calculated Pearson's correlation coefficients between the stigma scales, the Maslach Burnout Inventory, and the K10 measure of psychological distress. We used Stata SE/12.0 for analyses. Factor analysis revealed a 35-item, five-factor model: worries about disclosure, internalized states, social judgment, social isolation, and discrimination (Cronbach's alphas 0.79-0.94). Our stigma measure was correlated with psychological distress (r = 0.40; p < .001), and with Maslach Burnout Inventory's emotional exhaustion (r = 0.27; p < .001), and depersonalization (0.23; p < .001) subscales, and was inversely correlated with Maslach Burnout Inventory's personal accomplishment subscale (r = -0.15; p < .05). Psychometric analysis of this scale reveals that it is a reliable and valid tool for measuring stigma in abortion providers, and may be helpful in evaluating stigma reduction programs. Copyright © 2017 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

  19. Experimental study of ERT monitoring ability to measure solute dispersion.

    PubMed

    Lekmine, Grégory; Pessel, Marc; Auradou, Harold

    2012-01-01

    This paper reports experimental measurements performed to test the ability of electrical resistivity tomography (ERT) imaging to provide quantitative information about transport parameters in porous media such as the dispersivity α, the mixing front velocity u, and the retardation factor R(f) associated with the sorption or trapping of the tracers in the pore structure. The flow experiments are performed in a homogeneous porous column placed between two vertical set of electrodes. Ionic and dyed tracers are injected from the bottom of the porous media over its full width. Under such condition, the mixing front is homogeneous in the transverse direction and shows an S-shape variation in the flow direction. The transport parameters are inferred from the variation of the concentration curves and are compared with data obtained from video analysis of the dyed tracer front. The variations of the transport parameters obtained from an inversion performed by the Gauss-Newton method applied on smoothness-constrained least-squares are studied in detail. While u and R(f) show a relatively small dependence on the inversion procedure, α is strongly dependent on the choice of the inversion parameters. Comparison with the video observations allows for the optimization of the parameters; these parameters are found to be robust with respect to changes in the flow condition and conductivity contrast. © 2011, The Author(s). Ground Water © 2011, National Ground Water Association.

  1. Free Triiodothyronine Concentrations are Inversely Associated with Elevated Carotid Intima-Media Thickness in Middle-Aged and Elderly Chinese Population.

    PubMed

    Zhou, Yulin; Zhao, Liebin; Wang, Tiange; Hong, Jie; Zhang, Jie; Xu, Baihui; Huang, Xiaolin; Xu, Min; Bi, Yufang

    2016-01-01

    Increased carotid artery intima media thickness (C-IMT) is an early feature of atherosclerosis. It has been reported to be altered in patients with thyroid dysfunction, and the evidence is still controversial. The present study aimed to explore the relationship between C-IMT and possible variations in thyroid function in Chinese adults aged 40 years and above. A community-based cross-sectional study was conducted among 2276 non-diabetic participants. Serum free triiodothyronine (FT3), free thyroxine (FT4), and thyroid stimulating hormone (TSH) were determined by chemiluminescent microparticle immunoassay. The prevalence of elevated C-IMT decreased according to FT3 quartiles (29.8%, 24.3%, 24.2%, and 22.2%, P for trend=0.005). In both univariate and multivariate linear regression analyses, FT3 levels were inversely associated with C-IMT (both P values ≤ 0.002). Multivariate-adjusted logistic regression analysis showed that high FT3 levels were associated with low prevalent elevated C-IMT. The adjusted odds ratio for elevated C-IMT was 0.71 (95% confidence interval, 0.52-0.99, P=0.04) when comparing the highest with the lowest quartile of FT3. Serum FT3 levels were inversely associated with elevated C-IMT in middle-aged and elderly Chinese adults without diabetes, independent of traditional risk factors for atherosclerosis.

  2. Dietary, Nutrient Patterns and Blood Essential Elements in Chinese Children with ADHD.

    PubMed

    Zhou, Fankun; Wu, Fengyun; Zou, Shipu; Chen, Ying; Feng, Chang; Fan, Guangqin

    2016-06-08

    Dietary or nutrient patterns represent the combined effects of foods or nutrients, and elucidate efficaciously the impact of diet on diseases. Because the pharmacotherapy on attention deficit hyperactivity disorder (ADHD) was reported be associated with certain side effects, and the etiology of ADHD is multifactorial, this study investigated the association of dietary and nutrient patterns with the risk of ADHD. We conducted a case-control study with 592 Chinese children including ADHD (n = 296) and non-ADHD (n = 296) aged 6-14 years old, matched by age and sex. Dietary and nutrient patterns were identified using factor analysis and a food frequency questionnaire. Blood essential elements levels were measured using atomic absorption spectrometry. A fish-white meat dietary pattern rich in shellfish, deep water fish, white meat, freshwater fish, organ meat and fungi and algae was inversely associated with ADHD (p = 0.006). Further analysis found that a mineral-protein nutrient pattern rich in zinc, protein, phosphorus, selenium, calcium and riboflavin was inversely associated with ADHD (p = 0.014). Additionally, the blood zinc was also negatively related to ADHD (p = 0.003). In conclusion, the fish-white meat dietary pattern and mineral-protein nutrient pattern may have beneficial effects on ADHD in Chinese children, and blood zinc may be helpful in distinguishing ADHD in Chinese children.

  3. Dietary, Nutrient Patterns and Blood Essential Elements in Chinese Children with ADHD

    PubMed Central

    Zhou, Fankun; Wu, Fengyun; Zou, Shipu; Chen, Ying; Feng, Chang; Fan, Guangqin

    2016-01-01

    Dietary or nutrient patterns represent the combined effects of foods or nutrients, and elucidate efficaciously the impact of diet on diseases. Because the pharmacotherapy on attention deficit hyperactivity disorder (ADHD) was reported be associated with certain side effects, and the etiology of ADHD is multifactorial, this study investigated the association of dietary and nutrient patterns with the risk of ADHD. We conducted a case-control study with 592 Chinese children including ADHD (n = 296) and non-ADHD (n = 296) aged 6–14 years old, matched by age and sex. Dietary and nutrient patterns were identified using factor analysis and a food frequency questionnaire. Blood essential elements levels were measured using atomic absorption spectrometry. A fish-white meat dietary pattern rich in shellfish, deep water fish, white meat, freshwater fish, organ meat and fungi and algae was inversely associated with ADHD (p = 0.006). Further analysis found that a mineral-protein nutrient pattern rich in zinc, protein, phosphorus, selenium, calcium and riboflavin was inversely associated with ADHD (p = 0.014). Additionally, the blood zinc was also negatively related to ADHD (p = 0.003). In conclusion, the fish-white meat dietary pattern and mineral-protein nutrient pattern may have beneficial effects on ADHD in Chinese children, and blood zinc may be helpful in distinguishing ADHD in Chinese children. PMID:27338457

  4. The relationship of quantitative nuclear morphology to molecular genetic alterations in the adenoma-carcinoma sequence of the large bowel.

    PubMed Central

    Mulder, J. W.; Offerhaus, G. J.; de Feyter, E. P.; Floyd, J. J.; Kern, S. E.; Vogelstein, B.; Hamilton, S. R.

    1992-01-01

    The relationship of abnormal nuclear morphology to molecular genetic alterations that are important in colorectal tumorigenesis is unknown. Therefore, Feulgen-stained isolated nuclei from 22 adenomas and 42 carcinomas that had been analyzed for ras gene mutations and allelic deletions on chromosomes 5q, 18q, and 17p were characterized by computerized image analysis. Both nuclear area and the nuclear shape factor representing irregularity correlated with adenoma-carcinoma progression (r = 0.57 and r = 0.52, P < 0.0001), whereas standard nuclear texture, a parameter of chromatin homogeneity, was inversely correlated with progression (r = -0.80, P < 0.0001). The nuclear parameters were strongly interrelated (P < 0.0005). In multivariate analysis, the nuclear parameters were predominantly associated with adenoma-carcinoma progression (P < or = 0.0001) and were not influenced significantly by the individual molecular genetic alterations. Nuclear texture, however, was inversely correlated with fractional allelic loss, a global measure of genetic changes, in carcinomas (r = -0.39, P = 0.011). The findings indicate that nuclear morphology in colorectal neoplasms is strongly related to tumor progression. Nuclear morphology and biologic behavior appear to be influenced by accumulated alterations in cancer-associated genes. Images Figure 1 PMID:1357973

  5. Description and Features of UX-Analyze

    DTIC Science & Technology

    2009-02-01

    POB model and GUI for EM63 Inversion The full Pasion -Oldenburg-Billings (POB) analysis assumes an axially symmetric (axial and transverse) tensor...output from the EM63 inversion. 1 Pasion , L.R., and Oldenburg, D.W., 2001, Locating and

  6. Visco-elastic controlled-source full waveform inversion without surface waves

    NASA Astrophysics Data System (ADS)

    Paschke, Marco; Krause, Martin; Bleibinhaus, Florian

    2016-04-01

    We developed a frequency-domain visco-elastic full waveform inversion for onshore seismic experiments with topography. The forward modeling is based on a finite-difference time-domain algorithm by Robertsson that uses the image-method to ensure a stress-free condition at the surface. The time-domain data is Fourier-transformed at every point in the model space during the forward modeling for a given set of frequencies. The motivation for this approach is the reduced amount of memory when computing kernels, and the straightforward implementation of the multiscale approach. For the inversion, we calculate the Frechet derivative matrix explicitly, and we implement a Levenberg-Marquardt scheme that allows for computing the resolution matrix. To reduce the size of the Frechet derivative matrix, and to stabilize the inversion, an adapted inverse mesh is used. The node spacing is controlled by the velocity distribution and the chosen frequencies. To focus the inversion on body waves (P, P-coda, and S) we mute the surface waves from the data. Consistent spatiotemporal weighting factors are applied to the wavefields during the Fourier transform to obtain the corresponding kernels. We test our code with a synthetic study using the Marmousi model with arbitrary topography. This study also demonstrates the importance of topography and muting surface waves in controlled-source full waveform inversion.

  7. WSJointInv2D-MT-DCR: An efficient joint two-dimensional magnetotelluric and direct current resistivity inversion

    NASA Astrophysics Data System (ADS)

    Amatyakul, Puwis; Vachiratienchai, Chatchai; Siripunvaraporn, Weerachai

    2017-05-01

    An efficient joint two-dimensional direct current resistivity (DCR) and magnetotelluric (MT) inversion, referred to as WSJointInv2D-MT-DCR, was developed with FORTRAN 95 based on the data space Occam's inversion algorithm. Our joint inversion software can be used to invert just the MT data or the DCR data, or invert both data sets simultaneously to get the electrical resistivity structures. Since both MT and DCR surveys yield the same resistivity structures, the two data types enhance each other leading to a better interpretation. Two synthetic and a real field survey are used here to demonstrate that the joint DCR and MT surveys can help constrain each other to reduce the ambiguities occurring when inverting the DCR or MT alone. The DCR data increases the lateral resolution of the near surface structures while the MT data reveals the deeper structures. When the MT apparent resistivity suffers from the static shift, the DCR apparent resistivity can serve as a replacement for the estimation of the static shift factor using the joint inversion. In addition, we also used these examples to show the efficiency of our joint inversion code. With the availability of our new joint inversion software, we expect the number of joint DCR and MT surveys to increase in the future.

  8. Breakpoint analysis of the pericentric inversion between chimpanzee chromosome 10 and the homologous chromosome 12 in humans.

    PubMed

    Kehrer-Sawatzki, H; Sandig, C A; Goidts, V; Hameister, H

    2005-01-01

    During this study, we analysed the pericentric inversion that distinguishes human chromosome 12 (HSA12) from the homologous chimpanzee chromosome (PTR10). Two large chimpanzee-specific duplications of 86 and 23 kb were observed in the breakpoint regions, which most probably occurred associated with the inversion. The inversion break in PTR10p caused the disruption of the SLCO1B3 gene in exon 11. However, the 86-kb duplication includes the functional SLCO1B3 locus, which is thus retained in the chimpanzee, although inverted to PTR10q. The second duplication spans 23 kb and does not contain expressed sequences. Eleven genes map to a region of about 1 Mb around the breakpoints. Six of these eleven genes are not among the differentially expressed genes as determined previously by comparing the human and chimpanzee transcriptome of fibroblast cell lines, blood leukocytes, liver and brain samples. These findings imply that the inversion did not cause major expression differences of these genes. Comparative FISH analysis with BACs spanning the inversion breakpoints in PTR on metaphase chromosomes of gorilla (GGO) confirmed that the pericentric inversion of the chromosome 12 homologs in GGO and PTR have distinct breakpoints and that humans retain the ancestral arrangement. These findings coincide with the trend observed in hominoid karyotype evolution that humans have a karyotype close to an ancestral one, while African great apes present with more derived chromosome arrangements. Copyright (c) 2005 S. Karger AG, Basel.

  9. M-Band Analysis of Chromosome Aberrations in Human Epithelial Cells Induced By Low- and High-Let Radiations

    NASA Technical Reports Server (NTRS)

    Hada, M.; Gersey, B.; Saganti, P. B.; Wilkins, R.; Gonda, S. R.; Cucinotta, F. A.; Wu, H.

    2007-01-01

    Energetic primary and secondary particles pose a health risk to astronauts in extended ISS and future Lunar and Mars missions. High-LET radiation is much more effective than low-LET radiation in the induction of various biological effects, including cell inactivation, genetic mutations, cataracts and cancer. Most of these biological endpoints are closely correlated to chromosomal damage, which can be utilized as a biomarker for radiation insult. In this study, human epithelial cells were exposed in vitro to gamma rays, 1 GeV/nucleon Fe ions and secondary neutrons whose spectrum is similar to that measured inside the Space Station. Chromosomes were condensed using a premature chromosome condensation technique and chromosome aberrations were analyzed with the multi-color banding (mBAND) technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of both interchromosomal (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). Results of the study confirmed the observation of higher incidence of inversions for high-LET irradiation. However, detailed analysis of the inversion type revealed that all of the three radiation types in the study induced a low incidence of simple inversions. Half of the inversions observed in the low-LET irradiated samples were accompanied by other types of intrachromosome aberrations, but few inversions were accompanied by interchromosome aberrations. In contrast, Fe ions induced a significant fraction of inversions that involved complex rearrangements of both the inter- and intrachromosome exchanges.

  10. Bayesian Analysis of the Association between Family-Level Factors and Siblings' Dental Caries.

    PubMed

    Wen, A; Weyant, R J; McNeil, D W; Crout, R J; Neiswanger, K; Marazita, M L; Foxman, B

    2017-07-01

    We conducted a Bayesian analysis of the association between family-level socioeconomic status and smoking and the prevalence of dental caries among siblings (children from infant to 14 y) among children living in rural and urban Northern Appalachia using data from the Center for Oral Health Research in Appalachia (COHRA). The observed proportion of siblings sharing caries was significantly different from predicted assuming siblings' caries status was independent. Using a Bayesian hierarchical model, we found the inclusion of a household factor significantly improved the goodness of fit. Other findings showed an inverse association between parental education and siblings' caries and a positive association between households with smokers and siblings' caries. Our study strengthens existing evidence suggesting that increased parental education and decreased parental cigarette smoking are associated with reduced childhood caries in the household. Our results also demonstrate the value of a Bayesian approach, which allows us to include household as a random effect, thereby providing more accurate estimates than obtained using generalized linear mixed models.

  11. Hypochondriasis and somatization in college women: a personal projects analysis.

    PubMed

    Karoly, P; Lecci, L

    1993-03-01

    Although the descriptive features of hypochondriasis and somatization have been widely studied, the motivational correlates (goal representations) of individuals manifesting abnormal illness patterns have not been considered. The Personal Projects Analysis method (Little, 1983) was used to contrast the health and nonhealth goals of female undergraduates. Subjects selected 10 goals for evaluation along a series of dimensions. When health pursuits alone were examined, hypochondriasis on the Minnesota Multiphasic Personality Inventory was found to correlate directly with goal appraisal dimensions subsumed by an anxiety-absorption factor and inversely with dimensions characterizing rewardingness, thus suggesting a negativity of health goal construal. Somatizers also pursued more health-related projects than did nonsomatizers; nonhealth goal cognition did not relate as strongly to hypochondriasis. Finally, using discriminant function analysis, goal representations were shown to significantly and substantially differentiate somatizers from nonsomatizers.

  12. Method of multivariate spectral analysis

    DOEpatents

    Keenan, Michael R.; Kotula, Paul G.

    2004-01-06

    A method of determining the properties of a sample from measured spectral data collected from the sample by performing a multivariate spectral analysis. The method can include: generating a two-dimensional matrix A containing measured spectral data; providing a weighted spectral data matrix D by performing a weighting operation on matrix A; factoring D into the product of two matrices, C and S.sup.T, by performing a constrained alternating least-squares analysis of D=CS.sup.T, where C is a concentration intensity matrix and S is a spectral shapes matrix; unweighting C and S by applying the inverse of the weighting used previously; and determining the properties of the sample by inspecting C and S. This method can be used to analyze X-ray spectral data generated by operating a Scanning Electron Microscope (SEM) with an attached Energy Dispersive Spectrometer (EDS).

  13. A Multicountry Ecological Study of Cancer Incidence Rates in 2008 with Respect to Various Risk-Modifying Factors

    PubMed Central

    Grant, William B.

    2013-01-01

    Observational and ecological studies are generally used to determine the presence of effect of cancer risk-modifying factors. Researchers generally agree that environmental factors such as smoking, alcohol consumption, poor diet, lack of physical activity, and low serum 25-hdyroxyvitamin D levels are important cancer risk factors. This ecological study used age-adjusted incidence rates for 21 cancers for 157 countries (87 with high-quality data) in 2008 with respect to dietary supply and other factors, including per capita gross domestic product, life expectancy, lung cancer incidence rate (an index for smoking), and latitude (an index for solar ultraviolet-B doses). The factors found to correlate strongly with multiple types of cancer were lung cancer (direct correlation with 12 types of cancer), energy derived from animal products (direct correlation with 12 types of cancer, inverse with two), latitude (direct correlation with six types, inverse correlation with three), and per capita gross national product (five types). Life expectancy and sweeteners directly correlated with three cancers, animal fat with two, and alcohol with one. Consumption of animal products correlated with cancer incidence with a lag time of 15–25 years. Types of cancer which correlated strongly with animal product consumption, tended to correlate weakly with latitude; this occurred for 11 cancers for the entire set of countries. Regression results were somewhat different for the 87 high-quality country data set and the 157-country set. Single-country ecological studies have inversely correlated nearly all of these cancers with solar ultraviolet-B doses. These results can provide guidance for prevention of cancer. PMID:24379012

  14. A multicountry ecological study of cancer incidence rates in 2008 with respect to various risk-modifying factors.

    PubMed

    Grant, William B

    2013-12-27

    Observational and ecological studies are generally used to determine the presence of effect of cancer risk-modifying factors. Researchers generally agree that environmental factors such as smoking, alcohol consumption, poor diet, lack of physical activity, and low serum 25-hdyroxyvitamin D levels are important cancer risk factors. This ecological study used age-adjusted incidence rates for 21 cancers for 157 countries (87 with high-quality data) in 2008 with respect to dietary supply and other factors, including per capita gross domestic product, life expectancy, lung cancer incidence rate (an index for smoking), and latitude (an index for solar ultraviolet-B doses). The factors found to correlate strongly with multiple types of cancer were lung cancer (direct correlation with 12 types of cancer), energy derived from animal products (direct correlation with 12 types of cancer, inverse with two), latitude (direct correlation with six types, inverse correlation with three), and per capita gross national product (five types). Life expectancy and sweeteners directly correlated with three cancers, animal fat with two, and alcohol with one. Consumption of animal products correlated with cancer incidence with a lag time of 15-25 years. Types of cancer which correlated strongly with animal product consumption, tended to correlate weakly with latitude; this occurred for 11 cancers for the entire set of countries. Regression results were somewhat different for the 87 high-quality country data set and the 157-country set. Single-country ecological studies have inversely correlated nearly all of these cancers with solar ultraviolet-B doses. These results can provide guidance for prevention of cancer.

  15. A Fine-Grained Pipelined Implementation for Large-Scale Matrix Inversion on FPGA

    NASA Astrophysics Data System (ADS)

    Zhou, Jie; Dou, Yong; Zhao, Jianxun; Xia, Fei; Lei, Yuanwu; Tang, Yuxing

    Large-scale matrix inversion play an important role in many applications. However to the best of our knowledge, there is no FPGA-based implementation. In this paper, we explore the possibility of accelerating large-scale matrix inversion on FPGA. To exploit the computational potential of FPGA, we introduce a fine-grained parallel algorithm for matrix inversion. A scalable linear array processing elements (PEs), which is the core component of the FPGA accelerator, is proposed to implement this algorithm. A total of 12 PEs can be integrated into an Altera StratixII EP2S130F1020C5 FPGA on our self-designed board. Experimental results show that a factor of 2.6 speedup and the maximum power-performance of 41 can be achieved compare to Pentium Dual CPU with double SSE threads.

  16. Inverse-designed stretchable metalens with tunable focal distance

    NASA Astrophysics Data System (ADS)

    Callewaert, Francois; Velev, Vesselin; Jiang, Shizhou; Sahakian, Alan Varteres; Kumar, Prem; Aydin, Koray

    2018-02-01

    In this paper, we present an inverse-designed 3D-printed all-dielectric stretchable millimeter wave metalens with a tunable focal distance. A computational inverse-design method is used to design a flat metalens made of disconnected polymer building blocks with complex shapes, as opposed to conventional monolithic lenses. The proposed metalens provides better performance than a conventional Fresnel lens, using lesser amount of material and enabling larger focal distance tunability. The metalens is fabricated using a commercial 3D-printer and attached to a stretchable platform. Measurements and simulations show that the focal distance can be tuned by a factor of 4 with a stretching factor of only 75%, a nearly diffraction-limited focal spot, and with a 70% relative focusing efficiency, defined as the ratio between power focused in the focal spot and power going through the focal plane. The proposed platform can be extended for design and fabrication of multiple electromagnetic devices working from visible to microwave radiation depending on scaling of the devices.

  17. [Inversion Model and Daily Variation of Total Phosphorus Concentrations in Taihu Lake Based on GOCI Data].

    PubMed

    Du, Cheng-gong; Li, Yun-mei; Wang, Qiao; Zhu, Li; Lü, Heng

    2016-03-15

    The TP concentration is an important index of water quality and an important influencing factor of eutrophication and algae blooms. Remote sensing technology has advantages of wide scope and high time limited efficacy. Monitoring the concentration of TP by satellite remote sensing is important for the study of water quality and eutrophication. In situ datasets collected during the three times of experiments in Taihu Lake between 2013 and 2014 were used to develop the TP inversion model based on GOCI data. The GOCI data in spring, summer, autumn and winter in 2014 were selected to analyze the time and space changes of TP concentration in Taihu Lake. The results showed that the TP algorithm was built up based on the variables, which was to use the eight band combination of GOCI data as variable, and build model using Multi factor linear regression method. The algorithm achieved more accurate TP estimation with R² = 0.898, MAPE = 14.296%, RMSE = 0.026 mg · L⁻¹. Meantime, a analysis on the precision of the model by using the measured sample points and the synchronous satellite images with MAPE = 33.642%, 22.551%, RMSE = 0.076 mg · L⁻¹, 0.028 mg · L⁻¹ on August 5, 2014 and October 24, 2014. Through the analysis of the 30 images on the four days of the four seasons, it showed that the absolute concentration of total phosphorus was different in different seasons. But temporal and spatial distribution of total phosphorus concentration was similar in the morning and afternoon. In spatial distribution, the TP concentration in Meiliang Bay, Zhushan Bay, Gonghu Bay, Xiaomei Port and Changdou Port in the southwest coast was at a continuously high position. The TP concentration change in different regions was influenced by wind direction, wind speed and other factors. The TP concentration highest in the morning, and then gradually decreased, this phenomenon reflected that the TP concentration was affected by temperature and light.

  18. Impact of Physical Activity on Glycemic Control and Prevalence of Cardiovascular Risk Factors in Adults With Type 1 Diabetes: A Cross-sectional Multicenter Study of 18,028 Patients.

    PubMed

    Bohn, Barbara; Herbst, Antje; Pfeifer, Martin; Krakow, Dietmar; Zimny, Stefan; Kopp, Florian; Melmer, Andreas; Steinacker, Jürgen M; Holl, Reinhard W

    2015-08-01

    Physical activity (PA) can improve cardiovascular risk in the general population and in patients with type 2 diabetes. Studies also indicate an HbA(1c)-lowering effect in patients with type 2 diabetes. Since reports in patients with type 1 diabetes are scarce, this analysis aimed to investigate whether there is an association between PA and glycemic control or cardiovascular risk in subjects with type 1 diabetes. A total of 18,028 adults (≥18 to <80 years of age) from Germany and Austria with type 1 diabetes from the Diabetes-Patienten-Verlaufsdokumentation (DPV) database were included. Patients were stratified according to their self-reported frequency of PA (PA0, inactive; PA1, one to two times per week; PA2, more than two times per week). Multivariable regression models were applied for glycemic control, diabetes-related comorbidities, and cardiovascular risk factors. Data were adjusted for sex, age, and diabetes duration. P values for trend were given. SAS 9.4 was used for statistical analysis. An inverse association between PA and HbA(1c), diabetic ketoacidosis, BMI, dyslipidemia (all P < 0.0001), and hypertension (P = 0.0150), as well as between PA and retinopathy or microalbuminuria (both P < 0.0001), was present. Severe hypoglycemia (assistance required) did not differ in PA groups (P = 0.8989), whereas severe hypoglycemia with coma was inversely associated with PA (P < 0.0001). PA seemed to be beneficial with respect to glycemic control, diabetes-related comorbidities, and cardiovascular risk factors without an increase of adverse events. Hence, our data underscore the recommendation for subjects with type 1 diabetes to perform regular PA. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  19. Alcohol and type 2 diabetes: The role of socioeconomic, lifestyle and psychosocial factors.

    PubMed

    Agardh, Emilie E; Lundin, Andreas; Lager, Anton; Allebeck, Peter; Koupil, Ilona; Andreasson, Sven; Östenson, Claes-Göran; Danielsson, Anna-Karin

    2018-05-01

    We investigate (a) alcohol consumption in association with type 2 diabetes, taking heavy episodic drinking (HED), socioeconomic, health and lifestyle, and psychosocial factors into account, and (b) whether a seemingly protective effect of moderate alcohol consumption on type 2 diabetes persists when stratified by occupational position. This population-based longitudinal cohort study comprises 16,223 Swedes aged 18-84 years who answered questionnaires about lifestyle, including alcohol consumption in 2002, and who were followed-up for self-reported or register-based diabetes in 2003-2011. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated in a multivariable-adjusted logistic regression model for all participants and stratified by high and low occupational position. We adjusted for HED, socioeconomic (occupational position, cohabiting status and unemployment), health and lifestyle (body mass index (BMI), blood pressure, smoking, physical inactivity, poor general health, anxiety/depression and psychosocial (low job control and poor social support) characteristics one by one, and the sets of these factors. Moderate consumption was inversely associated with type 2 diabetes after controlling for health and lifestyle (OR=0.47; 95% CI: 0.29-0.79) and psychosocial factors (OR=0.40; 95% CI: 0.22-0.79) when compared to non-drinkers. When adjusting for socioeconomic factors, there was still an inverse but non-significant association (OR=0.59; 95% CI: 0.35-1.00). In those with high occupational position, there was no significant association between moderate consumption and type 2 diabetes after adjusting for socioeconomic (OR=0.67; 95% CI: 0.3-1.52), health and lifestyle (OR=0.70; 95% CI: 0.32-1.5), and psychosocial factors (OR=0.75; 95% CI: 0.23-2.46). On the contrary, in those with low occupational position, ORs decreased from 0.55 (95% CI: 0.28-1.1) to 0.35 (95% CI: 0.15-0.82) when adjusting for psychosocial factors, a decrease that was solely due to low job control. HED did not influence any of these associations. Moderate alcohol consumption is associated with a lower risk of type 2 diabetes, after adjusting for HED, health and lifestyle, and psychosocial characteristics. The association was inverse but non-significant after adjusting for socioeconomic factors. When stratified by occupational position, there was an inverse association only in those with low occupational position and after adjusting for low job control.

  20. Inverse statistics and information content

    NASA Astrophysics Data System (ADS)

    Ebadi, H.; Bolgorian, Meysam; Jafari, G. R.

    2010-12-01

    Inverse statistics analysis studies the distribution of investment horizons to achieve a predefined level of return. This distribution provides a maximum investment horizon which determines the most likely horizon for gaining a specific return. There exists a significant difference between inverse statistics of financial market data and a fractional Brownian motion (fBm) as an uncorrelated time-series, which is a suitable criteria to measure information content in financial data. In this paper we perform this analysis for the DJIA and S&P500 as two developed markets and Tehran price index (TEPIX) as an emerging market. We also compare these probability distributions with fBm probability, to detect when the behavior of the stocks are the same as fBm.

  1. Children's strategies to solving additive inverse problems: a preliminary analysis

    NASA Astrophysics Data System (ADS)

    Ding, Meixia; Auxter, Abbey E.

    2017-03-01

    Prior studies show that elementary school children generally "lack" formal understanding of inverse relations. This study goes beyond lack to explore what children might "have" in their existing conception. A total of 281 students, kindergarten to third grade, were recruited to respond to a questionnaire that involved both contextual and non-contextual tasks on inverse relations, requiring both computational and explanatory skills. Results showed that children demonstrated better performance in computation than explanation. However, many students' explanations indicated that they did not necessarily utilize inverse relations for computation. Rather, they appeared to possess partial understanding, as evidenced by their use of part-whole structure, which is a key to understanding inverse relations. A close inspection of children's solution strategies further revealed that the sophistication of children's conception of part-whole structure varied in representation use and unknown quantity recognition, which suggests rich opportunities to develop students' understanding of inverse relations in lower elementary classrooms.

  2. Geophysical approaches to inverse problems: A methodological comparison. Part 1: A Posteriori approach

    NASA Technical Reports Server (NTRS)

    Seidman, T. I.; Munteanu, M. J.

    1979-01-01

    The relationships of a variety of general computational methods (and variances) for treating illposed problems such as geophysical inverse problems are considered. Differences in approach and interpretation based on varying assumptions as to, e.g., the nature of measurement uncertainties are discussed along with the factors to be considered in selecting an approach. The reliability of the results of such computation is addressed.

  3. Inverse relationship between Alzheimer's disease and cancer, and other factors contributing to Alzheimer's disease: a systematic review.

    PubMed

    Shafi, Ovais

    2016-11-22

    The AD etiology is yet not properly known. Interactions among environmental factors, multiple susceptibility genes and aging, contribute to AD. This study investigates the factors that play role in causing AD and how changes in cellular pathways contribute to AD. PUBMED database, MEDLINE database and Google Scholar were searched with no date restrictions for published articles involving cellular pathways with roles in cancers, cell survival, growth, proliferation, development, aging, and also contributing to Alzheimer's disease. This research explores inverse relationship between AD and cancer, also investigates other factors behind AD using several already published research literature to find the etiology of AD. Cancer and Alzheimer's disease have inverse relationship in many aspects such as P53, estrogen, neurotrophins and growth factors, growth and proliferation, cAMP, EGFR, Bcl-2, apoptosis pathways, IGF-1, HSV, TDP-43, APOE variants, notch signals and presenilins, NCAM, TNF alpha, PI3K/AKT/MTOR pathway, telomerase, ROS, ACE levels. AD occurs when brain neurons have weakened growth, cell survival responses, maintenance mechanisms, weakened anti-stress responses such as Vimentin, Carbonic anhydrases, HSPs, SAPK. In cancer, these responses are upregulated and maintained. Evolutionarily conserved responses and maintenance mechanisms such as FOXO are impaired in AD. Countermeasures or compensatory mechanisms by AD affected neurons such as Tau, Beta Amyloid, S100, are last attempts for survival which may be protective for certain time, or can speed up AD in Alzheimer's microenvironment via C-ABL activation, GSK3, neuro-inflammation. Alzheimer's disease and Cancer have inverse relationship; many factors that are upregulated in any cancer to sustain growth and survival are downregulated in Alzheimer's disease contributing to neuro-degeneration. When aged neurons or genetically susceptible neurons have weakened growth, cell survival and anti-stress responses, age related gene expression changes, altered regulation of cell death and maintenance mechanisms, they contribute to Alzheimer's disease. Countermeasures by AD neurons such as Beta Amyloid Plaques, NFTs, S100, are last attempts for survival and this provides neuroprotection for certain time and ultimately may become pathological and speed up AD. This study may contribute in developing new potential diagnostic tests, interventions and treatments.

  4. Targeted inversion and reversion of the blood coagulation factor 8 gene in human iPS cells using TALENs.

    PubMed

    Park, Chul-Yong; Kim, Jungeun; Kweon, Jiyeon; Son, Jeong Sang; Lee, Jae Souk; Yoo, Jeong-Eun; Cho, Sung-Rae; Kim, Jong-Hoon; Kim, Jin-Soo; Kim, Dong-Wook

    2014-06-24

    Hemophilia A, one of the most common genetic bleeding disorders, is caused by various mutations in the blood coagulation factor VIII (F8) gene. Among the genotypes that result in hemophilia A, two different types of chromosomal inversions that involve a portion of the F8 gene are most frequent, accounting for almost half of all severe hemophilia A cases. In this study, we used a transcription activator-like effector nuclease (TALEN) pair to invert a 140-kbp chromosomal segment that spans the portion of the F8 gene in human induced pluripotent stem cells (iPSCs) to create a hemophilia A model cell line. In addition, we reverted the inverted segment back to its normal orientation in the hemophilia model iPSCs using the same TALEN pair. Importantly, we detected the F8 mRNA in cells derived from the reverted iPSCs lines, but not in those derived from the clones with the inverted segment. Thus, we showed that TALENs can be used both for creating disease models associated with chromosomal rearrangements in iPSCs and for correcting genetic defects caused by chromosomal inversions. This strategy provides an iPSC-based novel therapeutic option for the treatment of hemophilia A and other genetic diseases caused by chromosomal inversions.

  5. Upsetting the apple cart: a community anticoagulation clinic survey of life event factors that undermine safe therapy.

    PubMed

    Edmundson, Sarah; Stuenkel, Diane L; Connolly, Phyllis M

    2005-09-01

    Anticoagulation therapy is a life-enhancing therapy for patients who are at risk for embolic events secondary to atrial fibrillation, valve replacement, and other comorbidities. Clinicians are motivated to decrease the amount of time that patients are either under- or over-anticoagulated, common conditions that decrease patient safety at either extreme. The primary purpose of this descriptive study was to examine the relationship between personal life event factors as measured by Norbeck's Life Events Questionnaire, core demographics such as age and income, and anticoagulation regulation. Although many factors affect anticoagulation therapy, the precise impact of life events, positive or negative, is unknown. The salient findings of this study (n = 202) showed a small, though statistically significant, inverse relationship (r = -0.184, P < .01) between negative life events and decreased time within therapeutic international normalized ratio. Total Life Event scores showed a statistically significant inverse relationship (r = -0.159, P < .05) to international normalized ratio time within therapeutic level. Lower income was inversely associated with higher negative Life Event scores (r = -0.192, P < .01). The findings demonstrate the need for strategies that address the potential impact of life events in conjunction with coexisting screening measures used in anticoagulation clinics. Implications for this study are limited by lack of methodology documenting concurrent social support factors and limitations of the research tool to reflect life event issues specific to outpatient seniors.

  6. Do the wealthy have a health advantage? Cardiovascular disease risk factors and wealth.

    PubMed

    Hajat, A; Kaufman, J S; Rose, K M; Siddiqi, A; Thomas, J C

    2010-12-01

    The use of wealth as a measure of socioeconomic status (SES) remains uncommon in epidemiological studies. When used, wealth is often measured crudely and at a single point in time. Our study explores the relationship between wealth and three cardiovascular disease (CVD) risk factors (smoking, obesity and hypertension) in a US population. We improve upon existing literature by using a detailed and validated measure of wealth in a longitudinal setting. We used four waves of data from the Panel Study of Income Dynamics (PSID) collected between 1999 and 2005. Inverse probability weights were employed to control for time-varying confounding and to estimate both relative (risk ratio) and absolute (risk difference) measures of effect. Wealth was defined as inflation-adjusted net worth and specified as a six category variable: one category for those with less than or equal to zero wealth and quintiles of positive wealth. After adjusting for income and other time-varying confounders, as well as baseline covariates, the risk of becoming obese was inversely related to wealth. There was a 40%-89% higher risk of becoming obese among the less wealthy relative to the wealthiest quintile and 11 to 25 excess cases (per 1000 persons) among the less wealthy groups over six years of follow up. Smoking initiation had similar but more moderate effects; risk ratios and differences both revealed a smaller magnitude of effect compared to obesity. Of the three CVD risk factors examined here, hypertension incidence had the weakest association with wealth, showing a smaller increased risk and fewer excess cases among the less wealthy groups. In conclusion, this study found a strong inverse association between wealth and obesity incidence, a moderate inverse association between wealth and smoking initiation and a weak inverse association between wealth and hypertension incidence after controlling for income and other time-varying confounders. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. Fosmid Cre-LoxP Inverse PCR Paired-End (Fosmid CLIP-PE), a Novel Method for Constructing Fosmid Pair-End Library (Seventh Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting 2012)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peng, Ze

    2012-06-01

    Ze Peng from DOE JGI presents "Fosmid Cre-LoxP Inverse PCR Paired-End (Fosmid CLIP-PE), a Novel Method for Constructing Fosmid Pair-End Library" at the 7th Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting held in June, 2012 in Santa Fe, NM.

  8. Killing Barney Fife: Law Enforcements Socially Constructed Perception of Violence and its Influence on Police Militarization

    DTIC Science & Technology

    2015-09-01

    then examines the correlation between violence and police militarization. A statistical analysis of crime data found an inverse relationship between...violence and police militarization. A statistical analysis of crime data found an inverse relationship between levels of reported violence and...events. The research then focused on the correlation between violence and police militarization. The research began with a detailed statistical

  9. A Sparsity-based Framework for Resolution Enhancement in Optical Fault Analysis of Integrated Circuits

    DTIC Science & Technology

    2015-01-01

    for IC fault detection . This section provides background information on inversion methods. Conventional inversion techniques and their shortcomings are...physical techniques, electron beam imaging/analysis, ion beam techniques, scanning probe techniques. Electrical tests are used to detect faults in 13 an...hand, there is also the second harmonic technique through which duty cycle degradation faults are detected by collecting the magnitude and the phase of

  10. Computational analysis for biodegradation of exogenously depolymerizable polymer

    NASA Astrophysics Data System (ADS)

    Watanabe, M.; Kawai, F.

    2018-03-01

    This study shows that microbial growth and decay in a biodegradation process of exogenously depolymerizable polymer are controlled by consumption of monomer units. Experimental outcomes for residual polymer were incorporated in inverse analysis for a degradation rate. The Gauss-Newton method was applied to an inverse problem for two parameter values associated with the microbial population. A biodegradation process of polyethylene glycol was analyzed numerically, and numerical outcomes were obtained.

  11. Fosmid Cre-LoxP Inverse PCR Paired-End (Fosmid CLIP-PE), a Novel Method for Constructing Fosmid Pair-End Library (Seventh Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting 2012)

    ScienceCinema

    Peng, Ze

    2018-01-24

    Ze Peng from DOE JGI presents "Fosmid Cre-LoxP Inverse PCR Paired-End (Fosmid CLIP-PE), a Novel Method for Constructing Fosmid Pair-End Library" at the 7th Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting held in June, 2012 in Santa Fe, NM.

  12. BioXTAS RAW: improvements to a free open-source program for small-angle X-ray scattering data reduction and analysis.

    PubMed

    Hopkins, Jesse Bennett; Gillilan, Richard E; Skou, Soren

    2017-10-01

    BioXTAS RAW is a graphical-user-interface-based free open-source Python program for reduction and analysis of small-angle X-ray solution scattering (SAXS) data. The software is designed for biological SAXS data and enables creation and plotting of one-dimensional scattering profiles from two-dimensional detector images, standard data operations such as averaging and subtraction and analysis of radius of gyration and molecular weight, and advanced analysis such as calculation of inverse Fourier transforms and envelopes. It also allows easy processing of inline size-exclusion chromatography coupled SAXS data and data deconvolution using the evolving factor analysis method. It provides an alternative to closed-source programs such as Primus and ScÅtter for primary data analysis. Because it can calibrate, mask and integrate images it also provides an alternative to synchrotron beamline pipelines that scientists can install on their own computers and use both at home and at the beamline.

  13. Fast Nonlinear Generalized Inversion of Gravity Data with Application to the Three-Dimensional Crustal Density Structure of Sichuan Basin, Southwest China

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Meng, Xiaohong; Li, Fang

    2017-11-01

    Generalized inversion is one of the important steps in the quantitative interpretation of gravity data. With appropriate algorithm and parameters, it gives a view of the subsurface which characterizes different geological bodies. However, generalized inversion of gravity data is time consuming due to the large amount of data points and model cells adopted. Incorporating of various prior information as constraints deteriorates the above situation. In the work discussed in this paper, a method for fast nonlinear generalized inversion of gravity data is proposed. The fast multipole method is employed for forward modelling. The inversion objective function is established with weighted data misfit function along with model objective function. The total objective function is solved by a dataspace algorithm. Moreover, depth weighing factor is used to improve depth resolution of the result, and bound constraint is incorporated by a transfer function to limit the model parameters in a reliable range. The matrix inversion is accomplished by a preconditioned conjugate gradient method. With the above algorithm, equivalent density vectors can be obtained, and interpolation is performed to get the finally density model on the fine mesh in the model domain. Testing on synthetic gravity data demonstrated that the proposed method is faster than conventional generalized inversion algorithm to produce an acceptable solution for gravity inversion problem. The new developed inversion method was also applied for inversion of the gravity data collected over Sichuan basin, southwest China. The established density structure in this study helps understanding the crustal structure of Sichuan basin and provides reference for further oil and gas exploration in this area.

  14. The inverse problem of refraction travel times, part II: Quantifying refraction nonuniqueness using a three-layer model

    USGS Publications Warehouse

    Ivanov, J.; Miller, R.D.; Xia, J.; Steeples, D.

    2005-01-01

    This paper is the second of a set of two papers in which we study the inverse refraction problem. The first paper, "Types of Geophysical Nonuniqueness through Minimization," studies and classifies the types of nonuniqueness that exist when solving inverse problems depending on the participation of a priori information required to obtain reliable solutions of inverse geophysical problems. In view of the classification developed, in this paper we study the type of nonuniqueness associated with the inverse refraction problem. An approach for obtaining a realistic solution to the inverse refraction problem is offered in a third paper that is in preparation. The nonuniqueness of the inverse refraction problem is examined by using a simple three-layer model. Like many other inverse geophysical problems, the inverse refraction problem does not have a unique solution. Conventionally, nonuniqueness is considered to be a result of insufficient data and/or error in the data, for any fixed number of model parameters. This study illustrates that even for overdetermined and error free data, nonlinear inverse refraction problems exhibit exact-data nonuniqueness, which further complicates the problem of nonuniqueness. By evaluating the nonuniqueness of the inverse refraction problem, this paper targets the improvement of refraction inversion algorithms, and as a result, the achievement of more realistic solutions. The nonuniqueness of the inverse refraction problem is examined initially by using a simple three-layer model. The observations and conclusions of the three-layer model nonuniqueness study are used to evaluate the nonuniqueness of more complicated n-layer models and multi-parameter cell models such as in refraction tomography. For any fixed number of model parameters, the inverse refraction problem exhibits continuous ranges of exact-data nonuniqueness. Such an unfavorable type of nonuniqueness can be uniquely solved only by providing abundant a priori information. Insufficient a priori information during the inversion is the reason why refraction methods often may not produce desired results or even fail. This work also demonstrates that the application of the smoothing constraints, typical when solving ill-posed inverse problems, has a dual and contradictory role when applied to the ill-posed inverse problem of refraction travel times. This observation indicates that smoothing constraints may play such a two-fold role when applied to other inverse problems. Other factors that contribute to inverse-refraction-problem nonuniqueness are also considered, including indeterminacy, statistical data-error distribution, numerical error and instability, finite data, and model parameters. ?? Birkha??user Verlag, Basel, 2005.

  15. Effects of the 2008 Global Economic Crisis on National Health Indicators: Results from the Korean National Health and Nutrition Examination Survey

    PubMed Central

    Shin, Jung-Hyun; Lee, Gyeongsil; Kim, Jun-Suk; Oh, Hyung-Seok; Lee, Keun-Seung; Hur, Yong

    2015-01-01

    Background The relationship between economics and health has been of great interest throughout the years. The accumulated data is not sufficient enough to carry out long-term studies from the viewpoint of morbidity, although Korea National Health and Nutrition Examination Survey (KNHANES) was carried out yearly since 1998 in Korea. Thus, we investigated the effect of the 2008 global economic crisis on health indicators of Korea. Methods Health indicators were selected by paired t-test based on 2007 and 2009 KNHANES data. Age, gender, body mass index (BMI), smoking, drinking, exercise, education, income, working status, and stress were used as confounding factors, which were analyzed with logistic and probit analyses. Validation was done by comparing gross domestic product (GDP) growth rates and probit analyses results of 2007-2012 KNHANES data. Results Among several health indicators, the prevalence of hypertension and stress perception was higher after the economic crisis. Factors related with higher hypertension prevalence include older age, male gender, higher BMI, no current tobacco use, recent drinking, lower education levels, and stress perception. Factors related with more stress perception were younger age, female gender, current smoking, lower education levels, and lower income. GDP growth rates, a macroeconomic indicator, are inversely associated with hypertension prevalence with a one-year lag, and also inversely associated with stress perception without time lag. Conclusion The economic crisis increased the prevalence of hypertension and stress perception. In the case of GDP growth rate change, hypertension was an inversely lagging indicator and stress perception was an inversely-related coincident indicator. PMID:26217479

  16. Effects of the 2008 Global Economic Crisis on National Health Indicators: Results from the Korean National Health and Nutrition Examination Survey.

    PubMed

    Shin, Jung-Hyun; Lee, Gyeongsil; Kim, Jun-Suk; Oh, Hyung-Seok; Lee, Keun-Seung; Hur, Yong; Cho, Be-Long

    2015-07-01

    The relationship between economics and health has been of great interest throughout the years. The accumulated data is not sufficient enough to carry out long-term studies from the viewpoint of morbidity, although Korea National Health and Nutrition Examination Survey (KNHANES) was carried out yearly since 1998 in Korea. Thus, we investigated the effect of the 2008 global economic crisis on health indicators of Korea. Health indicators were selected by paired t-test based on 2007 and 2009 KNHANES data. Age, gender, body mass index (BMI), smoking, drinking, exercise, education, income, working status, and stress were used as confounding factors, which were analyzed with logistic and probit analyses. Validation was done by comparing gross domestic product (GDP) growth rates and probit analyses results of 2007-2012 KNHANES data. Among several health indicators, the prevalence of hypertension and stress perception was higher after the economic crisis. Factors related with higher hypertension prevalence include older age, male gender, higher BMI, no current tobacco use, recent drinking, lower education levels, and stress perception. Factors related with more stress perception were younger age, female gender, current smoking, lower education levels, and lower income. GDP growth rates, a macroeconomic indicator, are inversely associated with hypertension prevalence with a one-year lag, and also inversely associated with stress perception without time lag. The economic crisis increased the prevalence of hypertension and stress perception. In the case of GDP growth rate change, hypertension was an inversely lagging indicator and stress perception was an inversely-related coincident indicator.

  17. Dietary fat intake and quality of life: the SUN project.

    PubMed

    Ruano, Cristina; Henriquez, Patricia; Bes-Rastrollo, Maira; Ruiz-Canela, Miguel; del Burgo, Cristina López; Sánchez-Villegas, Almudena

    2011-11-02

    Few studies have related nutritional factors with quality of life in healthy populations. The purpose of the study was to assess whether dietary fat intake is associated to mental and physical quality of life. This analysis included 8,430 participants from the SUN (Seguimiento Universidad de Navarra) Project. The intake of saturated fatty acids (SFA), polyunsaturated fatty acids (PUFA), trans unsaturated fatty acids (TFA), and monounsaturated fatty acids (MUFA) was assessed through a 136-item food frequency questionnaire at baseline. Quality of life was measured with the SF-36 Health Survey after 4 years of follow-up. Generalized Linear Models were fitted to assess the regression coefficients (b) and their 95% confidence intervals (95% CI) for the 8 domains of the SF-36 according to successive quintiles of each kind of fatty acids intake. The multivariate-adjusted models revealed a significant inverse association for SFA intake (in quintiles) and two of the physical domains (physical functioning and general health). E.g. for general health domain: (highest quintile of intake (Q5) vs. lowest quintile (Q1), b = -1.6; 95% CI = -3.1, -0.1. General health also showed a dose-response relationship (p for trend < 0.05). For TFA intake (in quintiles), a significant inverse association was found for most of the mental domains (vitality, social functioning and role emotional). E.g. for vitality domain (Q5) vs. (Q1), b = -2.0, 95% CI = -3.4 to -0.6. We also found an inverse association between TFA intake and the bodily pain domain: (Q5 vs. Q1), b = -2.6; 95% CI = -4.4 to -0.8, with a statistically significant dose-response relationship (p for trend < 0.05). Except for TFA intake and the mental domains, the rest of the associations were attenuated when we repeated the analysis adjusting for adherence to the Mediterranean diet. A detrimental relationship between TFA intake at baseline and most of the SF-36 mental domains measured 4 years later were found, whereas weak inverse associations were found for SFA intake and some physical domains.

  18. Analysis of uncertainties in GOSAT-inferred regional CO2 fluxes

    NASA Astrophysics Data System (ADS)

    Ishizawa, M.; Shirai, T.; Maksyutov, S. S.; Yoshida, Y.; Morino, I.; Inoue, M.; Nakatsuru, T.; Uchino, O.; Mabuchi, K.

    2016-12-01

    Satellite-based CO2 measurements have potential for improving our understanding global carbon cycle because of more spatiotemporal coverage than those from ground-based observations. Since the Greenhouse gases Observing Satellite (GOSAT) was launched in January 2009, it has been measuring the column-average dry air-mole function of CO2 (XCO2) from the space. To utilize the GOSAT XCO2 for better CO2 flux estimates, several challenges should be overcome. Systematic errors (biases) in XCO2 retrievals are a major factor which leads to large differences among inverted CO2 fluxes. Temporally variable data coverage and density are also taken into account when interpreting the estimated surface fluxes. In this study, we employ an atmospheric inverse model to investigate the impacts of retrievals biases and temporally varying global distribution of GOSAT XCO2 on surface CO2 flux estimates. Inversions are performed for 2009-2013, with several subsets of the 5-year record of GOSAT XCO2 (v2.21) and its bias-corrected XCO2. GOSAT XCO2 data consist of three types: H-gain for vegetated lands, M-gain for bright surfaces (desert areas), and sun-glint for ocean surface. The results show that the global spatial distributions of estimated CO2 fluxes depend on the subset of XCO2 used. M-gain XCO2 results in unrealistically high CO2 emissions in and around the Middle East, including the neighboring ocean regions. On the other hand, M-gain XCO2 causes compensating unrealistic uptakes far beyond M-gain regions in low latitudes, also partially contributing on the summer uptake in Europe. The joint inversions with both surface measurements and GOSAT XCO2 data obtain larger flux gradient between the northern extra-tropics and the tropics than the inversion with surface measurements only for the first 2 years. Recently, these North-South gradients seem to be gradually reducing as the tropics become a weaker source or turn into a sink, while the net emission strength in East Asia is increasing. The 5-year XCO2 data allows us detailed analysis of uncertainties in GOSAT-inferred fluxes and assessment of GOSAT XCO2 biases.

  19. Relationship among academic engagement, burnout and student perceptions of curriculum delivery in Speech and Language Therapy Students from University of Concepcion, Chile.

    PubMed

    Glaria, Rocio; Carmona, Lorena; Perez, Cristhian; Parra, Paula

    2017-09-01

    To relate engagement and academic burnout with curriculum evaluation among speech therapy students. This observational, cross-sectional study was conducted at the end of the first academic semester for each level and at the end of a theoretical class in order to ensure the maximum participation rate at the University of Concepción, Concepción, Chile, and comprised students of a speech and language therapy programme.Curriculum evaluation scale, academic engagement and academic burnout questionnaires were used. STATA SE 11 was used for statistical analysis. Of the 200 participants, 157(78.50%) were women and 43(21.50%) men. The overall mean age was 20.81±2.15 years (range: 18-30 years). Emotional burnout was inversely correlated with the evaluation of teaching and evaluation methods, distribution of fields, teaching team and achievement of objectives (p<0.05 each). Depersonalisation was inversely associated with the distribution of teaching and learning activities (r=-0.13; p<0.05). Lack of personal accomplishment was also significantly and statistically associated with seven out of the eight factors of the curriculum evaluation scale (p<0.05 each). Involvement in studies was statistically and significantly related to all factors (p<0.05 each), except the achievement of objectives. Finally, satisfaction with studies was directly, statistically and significantly related to six of the eight factors (p<0.05 each). A more positive evaluation of the academic curriculum was associated with lower levels of burnout and higher levels of academic engagement.

  20. Attenuation of Lg waves in the New Madrid seismic zone of the central United States using the coda normalization method

    NASA Astrophysics Data System (ADS)

    Nazemi, Nima; Pezeshk, Shahram; Sedaghati, Farhad

    2017-08-01

    Unique properties of coda waves are employed to evaluate the frequency dependent quality factor of Lg waves using the coda normalization method in the New Madrid seismic zone of the central United States. Instrument and site responses are eliminated and source functions are isolated to construct the inversion problem. For this purpose, we used 121 seismograms from 37 events with moment magnitudes, M, ranging from 2.5 to 5.2 and hypocentral distances from 120 to 440 km recorded by 11 broadband stations. A singular value decomposition (SVD) algorithm is used to extract Q values from the data, while the geometric spreading exponent is assumed to be a constant. Inversion results are then fitted with a power law equation from 3 to 12 Hz to derive the frequency dependent quality factor function. The final results of the analysis are QVLg (f) = (410 ± 38) f0.49 ± 0.05 for the vertical component and QHLg (f) = (390 ± 26) f0.56 ± 0.04 for the horizontal component, where the term after ± sign represents one standard error. For stations within the Mississippi embayment with an average sediment depth of 1 km around the Memphis metropolitan area, estimation of quality factor using the coda normalization method is not well-constrained at low frequencies (f < 3 Hz). There may be several reasons contributing to this issue, such as low frequency surface wave contamination, site effects, or even a change in coda wave scattering regime which can exacerbate the scatter of the data.

  1. Effect of particle size on hydroxyapatite crystal-induced tumor necrosis factor alpha secretion by macrophages.

    PubMed

    Nadra, Imad; Boccaccini, Aldo R; Philippidis, Pandelis; Whelan, Linda C; McCarthy, Geraldine M; Haskard, Dorian O; Landis, R Clive

    2008-01-01

    Macrophages may promote a vicious cycle of inflammation and calcification in the vessel wall by ingesting neointimal calcific deposits (predominantly hydroxyapatite) and secreting tumor necrosis factor (TNF)alpha, itself a vascular calcifying agent. Here we have investigated whether particle size affects the proinflammatory potential of hydroxyapatite crystals in vitro and whether the nuclear factor (NF)-kappaB pathway plays a role in the macrophage TNFalpha response. The particle size and nano-topography of nine different crystal preparations was analyzed by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and gas sorbtion analysis. Macrophage TNFalpha secretion was inversely related to hydroxyapatite particle size (P=0.011, Spearman rank correlation test) and surface pore size (P=0.014). A necessary role for the NF-kappaB pathway was demonstrated by time-dependent I kappaB alpha degradation and sensitivity to inhibitors of I kappaB alpha degradation. To test whether smaller particles were intrinsically more bioactive, their mitogenic activity on fibroblast proliferation was examined. This showed close correlation between TNFalpha secretion and crystal-induced fibroblast proliferation (P=0.007). In conclusion, the ability of hydroxyapatite crystals to stimulate macrophage TNFalpha secretion depends on NF-kappaB activation and is inversely related to particle and pore size, with crystals of 1-2 microm diameter and pore size of 10-50 A the most bioactive. Microscopic calcific deposits in early stages of atherosclerosis may therefore pose a greater inflammatory risk to the plaque than macroscopically or radiologically visible deposits in more advanced lesions.

  2. Determinants of quality of life in patients with fibromyalgia: A structural equation modeling approach.

    PubMed

    Lee, Jeong-Won; Lee, Kyung-Eun; Park, Dong-Jin; Kim, Seong-Ho; Nah, Seong-Su; Lee, Ji Hyun; Kim, Seong-Kyu; Lee, Yeon-Ah; Hong, Seung-Jae; Kim, Hyun-Sook; Lee, Hye-Soon; Kim, Hyoun Ah; Joung, Chung-Il; Kim, Sang-Hyon; Lee, Shin-Seok

    2017-01-01

    Health-related quality of life (HRQOL) in patients with fibromyalgia (FM) is lower than in patients with other chronic diseases and the general population. Although various factors affect HRQOL, no study has examined a structural equation model of HRQOL as an outcome variable in FM patients. The present study assessed relationships among physical function, social factors, psychological factors, and HRQOL, and the effects of these variables on HRQOL in a hypothesized model using structural equation modeling (SEM). HRQOL was measured using SF-36, and the Fibromyalgia Impact Questionnaire (FIQ) was used to assess physical dysfunction. Social and psychological statuses were assessed using the Beck Depression Inventory (BDI), the State-Trait Anxiety Inventory (STAI), the Arthritis Self-Efficacy Scale (ASES), and the Social Support Scale. SEM analysis was used to test the structural relationships of the model using the AMOS software. Of the 336 patients, 301 (89.6%) were women with an average age of 47.9±10.9 years. The SEM results supported the hypothesized structural model (χ2 = 2.336, df = 3, p = 0.506). The final model showed that Physical Component Summary (PCS) was directly related to self-efficacy and inversely related to FIQ, and that Mental Component Summary (MCS) was inversely related to FIQ, BDI, and STAI. In our model of FM patients, HRQOL was affected by physical, social, and psychological variables. In these patients, higher levels of physical function and self-efficacy can improve the PCS of HRQOL, while physical function, depression, and anxiety negatively affect the MCS of HRQOL.

  3. Association of sedentary behavior time with ideal cardiovascular health: the ORISCAV-LUX study.

    PubMed

    Crichton, Georgina E; Alkerwi, Ala'a

    2014-01-01

    Recently attention has been drawn to the health impacts of time spent engaging in sedentary behaviors. No studies have examined sedentary behaviors in relation to the newly defined construct of ideal cardiovascular health, which incorporates three health factors (blood pressure, total cholesterol, fasting plasma glucose) and four behaviors (physical activity, smoking, body mass index, diet). The purpose of this study was to examine associations between sedentary behaviors, including sitting time, and time spent viewing television and in front of a computer, with cardiovascular health, in a representative sample of adults from Luxembourg. A cross-sectional analysis of 1262 participants in the Observation of Cardiovascular Risk Factors in Luxembourg study was conducted, who underwent objective cardiovascular health assessments and completed the International Physical Activity Questionnaire. A Cardiovascular Health Score was calculated based on the number of health factors and behaviors at ideal levels. Sitting time on a weekday, television time, and computer time (both on a workday and a day off), were related to the Cardiovascular Health Score. Higher weekday sitting time was significantly associated with a poorer Cardiovascular Health Score (p = 0.002 for linear trend), after full adjustment for age, gender, education, income and occupation. Television time was inversely associated with the Cardiovascular Health Score, on both a workday and a day off (p = 0.002 for both). A similar inverse relationship was observed between the Cardiovascular Health Score and computer time, only on a day off (p = 0.04). Higher time spent sitting, viewing television, and using a computer during a day off may be unfavorably associated with ideal cardiovascular health.

  4. Determinants of quality of life in patients with fibromyalgia: A structural equation modeling approach

    PubMed Central

    Lee, Jeong-Won; Lee, Kyung-Eun; Park, Dong-Jin; Kim, Seong-Ho; Nah, Seong-Su; Lee, Ji Hyun; Kim, Seong-Kyu; Lee, Yeon-Ah; Hong, Seung-Jae; Kim, Hyun-Sook; Lee, Hye-Soon; Kim, Hyoun Ah; Joung, Chung-Il; Kim, Sang-Hyon

    2017-01-01

    Objective Health-related quality of life (HRQOL) in patients with fibromyalgia (FM) is lower than in patients with other chronic diseases and the general population. Although various factors affect HRQOL, no study has examined a structural equation model of HRQOL as an outcome variable in FM patients. The present study assessed relationships among physical function, social factors, psychological factors, and HRQOL, and the effects of these variables on HRQOL in a hypothesized model using structural equation modeling (SEM). Methods HRQOL was measured using SF-36, and the Fibromyalgia Impact Questionnaire (FIQ) was used to assess physical dysfunction. Social and psychological statuses were assessed using the Beck Depression Inventory (BDI), the State-Trait Anxiety Inventory (STAI), the Arthritis Self-Efficacy Scale (ASES), and the Social Support Scale. SEM analysis was used to test the structural relationships of the model using the AMOS software. Results Of the 336 patients, 301 (89.6%) were women with an average age of 47.9±10.9 years. The SEM results supported the hypothesized structural model (χ2 = 2.336, df = 3, p = 0.506). The final model showed that Physical Component Summary (PCS) was directly related to self-efficacy and inversely related to FIQ, and that Mental Component Summary (MCS) was inversely related to FIQ, BDI, and STAI. Conclusions In our model of FM patients, HRQOL was affected by physical, social, and psychological variables. In these patients, higher levels of physical function and self-efficacy can improve the PCS of HRQOL, while physical function, depression, and anxiety negatively affect the MCS of HRQOL. PMID:28158289

  5. Usual Cruciferous Vegetable Consumption and Ovarian Cancer: A Case-Control Study.

    PubMed

    McManus, Hallie; Moysich, Kirsten B; Tang, Li; Joseph, Janine; McCann, Susan E

    2018-01-01

    Ovarian cancer is the fifth leading cause of cancer-related deaths among women, primarily due to diagnosis at late stages. Therefore, identification of modifiable risk factors for this disease is warranted. Using the Patient Epidemiology Data System (PEDS), collected from 1981 to 1998 at Roswell Park Cancer Institute, Buffalo, NY, we conducted a hospital-based, case-control analysis of self-reported cruciferous vegetable intake and ovarian cancer among 675 women with primary, incident ovarian cancer, and 1275 without cancer. Cruciferous vegetable intake was queried using a 44-item food frequency questionnaire (FFQ). Odds ratios (OR) and 95% confidence intervals (CI) were estimated with logistic regression, adjusting for age, body mass index (BMI), education, smoking status, parity, family history of ovarian cancer, total fruit consumption, total meat consumption, and total noncruciferous vegetable consumption. We observed a significant inverse association for women with highest vs. lowest intakes of total vegetables (OR = 0.65, 95% CI = 0.46-0.92), cooked cauliflower (OR = 0.82, 95% CI = 0.67-0.99), and cooked greens (OR = 0.63, 95% CI = 0.46-0.86) and an inverse, dose-dependent association between cooked cruciferous vegetables intake and ovarian cancer (for each additional ten servings per month, OR = 0.85, 95% CI = 0.76-0.96). These findings suggest that a diet that includes cruciferous vegetables could be an important modifiable risk factor for ovarian cancer.

  6. Mercury in Hair Is Inversely Related to Disease Associated Damage in Systemic Lupus Erythematosus

    PubMed Central

    Crowe, William; Doherty, Leanne; Watson, Gene; Armstrong, David; Ball, Elisabeth; Magee, Pamela; Allsopp, Philip; Bell, Aubrey; Strain, J. J.; McSorley, Emeir

    2015-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune inflammatory disease, and environmental factors are proposed to exacerbate existing symptoms. One such environmental factor is mercury. The aim of this study was to investigate the relationship between exposure to mercury (Hg) and disease activity and disease associated damage in Total Hg concentrations in hair and urine were measured in 52 SLE patients. Dental amalgams were quantified. Disease activity was assessed using three indexes including the British Isles Lupus Assessment Group Index (BILAG). Disease associated damage was measured using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology SLICC/ACR Damage Index. Pearson’s correlation identified a significant negative correlation between hair Hg and BILAG (r = −0.323, p = 0.029) and SLICC/ACR (r = −0.377, p = 0.038). Multiple regression analysis identified hair Hg as a significant predictor of disease associated damage as determined by SLICC/ACR (β = −0.366, 95% confidence interval (CI): −1.769, −0.155 p = 0.019). Urinary Hg was not related to disease activity or damage. Fish consumption is the primary route of MeHg exposure in humans and the inverse association of hair Hg with disease activity observed here might be explained by the anti-inflammatory effects of n-3 long chain polyunsaturated fatty acids also found in fish. PMID:26703710

  7. Integrative neural networks model for prediction of sediment rating curve parameters for ungauged basins

    NASA Astrophysics Data System (ADS)

    Atieh, M.; Mehltretter, S. L.; Gharabaghi, B.; Rudra, R.

    2015-12-01

    One of the most uncertain modeling tasks in hydrology is the prediction of ungauged stream sediment load and concentration statistics. This study presents integrated artificial neural networks (ANN) models for prediction of sediment rating curve parameters (rating curve coefficient α and rating curve exponent β) for ungauged basins. The ANN models integrate a comprehensive list of input parameters to improve the accuracy achieved; the input parameters used include: soil, land use, topographic, climatic, and hydrometric data sets. The ANN models were trained on the randomly selected 2/3 of the dataset of 94 gauged streams in Ontario, Canada and validated on the remaining 1/3. The developed models have high correlation coefficients of 0.92 and 0.86 for α and β, respectively. The ANN model for the rating coefficient α is directly proportional to rainfall erosivity factor, soil erodibility factor, and apportionment entropy disorder index, whereas it is inversely proportional to vegetation cover and mean annual snowfall. The ANN model for the rating exponent β is directly proportional to mean annual precipitation, the apportionment entropy disorder index, main channel slope, standard deviation of daily discharge, and inversely proportional to the fraction of basin area covered by wetlands and swamps. Sediment rating curves are essential tools for the calculation of sediment load, concentration-duration curve (CDC), and concentration-duration-frequency (CDF) analysis for more accurate assessment of water quality for ungauged basins.

  8. Inverse Relationship between Serum VEGF Levels and Late In-Stent Restenosis of Drug-Eluting Stents

    PubMed Central

    Shen, Li; Ji, Meng; Cai, Sishi; Chen, Jiahui; Yao, Zhifeng

    2017-01-01

    Late in-stent restenosis (ISR) has raised concerns regarding the long-term efficacy of drug-eluting stents (DES). The role of vascular endothelial growth factor (VEGF) in the pathological process of ISR is controversial. This retrospective study aimed to investigate the relationship between serum VEGF levels and late ISR in patients with DES implantation. A total of 158 patients who underwent angiography follow-up beyond 1 year after intervention were included. The study population was classified into ISR and non-ISR groups. The ISR group was further divided according to follow-up duration and Mehran classification. VEGF levels were significantly lower in the ISR group than in the non-ISR group [96.34 (48.18, 174.14) versus 179.14 (93.59, 307.74) pg/mL, p < 0.0001]. Multivariate regression revealed that VEGF level, procedure age, and low-density lipoprotein cholesterol were independent risk factors for late ISR formation. Subgroup analysis demonstrated that VEGF levels were even lower in the very late (≥5 years) and diffuse ISR group (Mehran patterns II, III, and IV) than in the late ISR group (1–4 years) and the focal ISR group (Mehran pattern I), respectively. Furthermore, significant difference was found between diffuse and focal ISR groups. Serum VEGF levels were inversely associated with late ISR after DES implantation. PMID:28373989

  9. Anatomical substrates of cognitive and clinical dimensions in first episode schizophrenia.

    PubMed

    Rigucci, S; Rossi-Espagnet, C; Ferracuti, S; De Carolis, A; Corigliano, V; Carducci, F; Mancinelli, I; Cicone, F; Tatarelli, R; Bozzao, A; Girardi, P; Comparelli, A

    2013-10-01

    To explore gray (GM) and white matter (WM) abnormalities and the relationships with neuropsychopathology in first-episode schizophrenia (FES). Nineteen patients with first episode of non-affective psychosis and 18 controls underwent a magnetic resonance voxel-based morphometry. Additionally, WM fractional anisotropy (FA) was calculated. For correlative analysis, symptoms and neuropsychological performances were scored by PANSS and by a comprehensive neuropsychological assessment respectively. Patients showed significantly decreased volume of left temporal lobe and disarray of all major WM tracts. Disorganized PANSS factor was inversely related to left cerebellar GM volume (corrected P = 0.03) and to WM FA of the left cerebellum, inferior fronto-occipital fasciculi (IFOF), and inferior longitudinal fasciculi (corrected P < 0.05). PANSS negative factor was inversely related to FA in the IFOF and superior longitudinal fasciculi (corrected P < 0.05). Impairment in facial emotion identification showed associations with temporo-occipital GM volume decrease (corrected P = 0.003) and WM disarray of superior and middle temporal gyri, anterior thalamic radiation, and superior longitudinal fasciculi (corrected P < 0.05). Speed of processing and visual memory correlated with WM abnormalities in fronto-temporal tracts. These results confirm how the structural development of key brain regions is related to neuropsychopathological dysfunction in FES, consistently with a neurodevelopmentally derived misconnection syndrome. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Synthetic Division and Matrix Factorization

    ERIC Educational Resources Information Center

    Barabe, Samuel; Dubeau, Franc

    2007-01-01

    Synthetic division is viewed as a change of basis for polynomials written under the Newton form. Then, the transition matrices obtained from a sequence of changes of basis are used to factorize the inverse of a bidiagonal matrix or a block bidiagonal matrix.

  11. New Factorization Techniques and Fast Serial and Parrallel Algorithms for Operational Space Control of Robot Manipulators

    NASA Technical Reports Server (NTRS)

    Fijany, Amir; Djouani, Karim; Fried, George; Pontnau, Jean

    1997-01-01

    In this paper a new factorization technique for computation of inverse of mass matrix, and the operational space mass matrix, as arising in implementation of the operational space control scheme, is presented.

  12. Risk and Protective Factors for Psychological Adjustment and Grades among Adolescents.

    ERIC Educational Resources Information Center

    Voydanoff, Patricia; Donnelly, Brenda W.

    1999-01-01

    Examines the ways in which two risk factors: negative peer behavior and time spent without an adult, and two protective factors: adolescent resources and parental behavior influence psychological adjustment and grades among adolescents ages 10 to 17 (N=745). Results indicate that negative peer behavior is inversely related to adolescent well…

  13. A meta-analysis of predictors of seizure freedom in the surgical management of focal cortical dysplasia.

    PubMed

    Rowland, Nathan C; Englot, Dario J; Cage, Tene A; Sughrue, Michael E; Barbaro, Nicholas M; Chang, Edward F

    2012-05-01

    Focal cortical dysplasia (FCD) is one of the most common causes of medically refractory epilepsy leading to surgery. However, seizure control outcomes reported in isolated surgical series are highly variable. As a result, it is not clear which variables are most crucial in predicting seizure freedom following surgery for FCD. The authors' aim was to determine the prognostic factors for seizure control in FCD by performing a meta-analysis of the published literature. A MEDLINE search of the published literature yielded 37 studies that met inclusion and exclusion criteria. Seven potential prognostic variables were determined from these studies and were dichotomized for analysis. For each variable, individual studies were weighted by inverse variance and combined to generate an odds ratio favoring seizure freedom. The methods complied with a standardized meta-analysis reporting protocol. Two thousand fourteen patients were included in the analysis. The overall rate of seizure freedom (Engel Class I) among patients undergoing surgery for FCD in the cohort of studies was 55.8% ± 16.2%. Partial seizures, a temporal location, detection with MRI, and a Type II Palmini histological classification were associated with higher rates of postoperative seizure control. As a treatment-related factor, complete resection of the anatomical or electrographic abnormality was the most important predictor overall of seizure freedom. Neither age nor electroencephalographic localization of the ictal onset significantly affected seizure freedom after surgery. Using a large population cohort pooled from the published literature, an analysis identified important factors that are prognostic in patients with epilepsy due to FCD. The most important of these factors-diagnostic imaging and resection-provide modalities through which improvements in the impact of FCD can be effected.

  14. The seed factor: how a combination of four observables can unveil the location of blazar GeV emission.

    NASA Astrophysics Data System (ADS)

    Harvey, Adam; Georganopoulos, Markos; Meyer, Eileen

    2018-01-01

    We present here a method for constraining the emission location of γ-rays in powerful, lined blazars (i.e., flat spectrum radio quasars (FSRQs)). We develop a diagnostic criteria, which we term the seed factor, to differentiate between γ-ray emission due to external Compton (EC) scattering in the broad line region (BLR) and the molecular torus (MT). The seed factor is determined entirely by four observable quantities; the synchrotron and inverse Compton (IC) peak frequencies, and the respective peak luminosities. It may thus be possible to use the seed factor to constrain the emission location in a model-independent way.We also present preliminary results of our analysis regarding the seed factor in quasi-simultaneous multi-wavelength SEDs from the Fermi LAT Bright AGN Sample (LBAS), historical data from the ASDC SED Builder of FSRQs in the the Monitoring Of Jets in Active galactic nuclei with VLBA Experiments (MOJAVE) sample, and quasi-simultaneous multi-wavelength SEDs from the Dynamic SEDs of southern blazars (DSSB) sample.

  15. Is high job control a risk factor for poor quality of life in workers with high autism spectrum tendencies? A cross-sectional survey at a factory in Japan.

    PubMed

    Hayakawa, Norika; Okada, Takashi; Nomura, Kenji; Tsukada, Tsukimi; Nakamura, Mieko

    2015-01-01

    To examine the effect of autism spectrum (AS) tendencies and psychosocial job characteristics on health-related quality of life (HRQOL) among factory workers. A questionnaire survey was administered to 376 Japanese factory employees from the same company (response rate: 83.6%) in 2010. Psychosocial job characteristics, including job demand, job control, and social support, were evaluated using the Job Content Questionnaire (JCQ). AS tendencies was assessed using the Autism-Spectrum Quotient (AQ), and HRQOL was assessed using the Medical Outcomes Study Short-Form General Health Survey (SF-8). Associations were investigated using multiple logistic regression analysis adjusted for confounders. In the multivariate analysis, AQ was positively (odds ratio [OR]: 3.94; 95% confidence interval [CI]: 1.70-9.73) and social support in the workplace was inversely (OR: 0.25; 95% CI: 0.10-0.57) associated with poor mental HRQOL. No significant interaction was observed between AQ and JCQ subitems. Only social support was inversely associated with poor physical HRQOL (OR and 95% CI for medium social support: 0.45 and 0.21-0.94), and a significant interaction between AQ and job control was observed (p=0.02), suggesting that high job control was associated with poor physical HRQOL among workers with high AQ, whereas low job control tended to be associated with poor physical HRQOL among others. Our results suggest that AS tendencies have a negative effect on workers' HRQOL and social support is a primary factor in maintaining HRQOL. Moreover, a structured work environment can maintain physical HRQOL in workers with high AS tendencies since higher job control will be stressful.

  16. Anthropometric parameters of nutritional assessment as predictive factors of arteriovenous fistula malfunction in patients undergoing hemodialysis.

    PubMed

    Gagliardi, Gian Manlio; Mancuso, Domenico; Falbo, Enrica; Mollica, Francesco; Mollica, Agata; Barcellona, Elisabetta; Senatore, Massimo; Bonofiglio, Renzo

    2012-01-01

    To evaluate the role of body mass index (BMI), waist circumference (W-C) and waist/hip ratio (WHR) on arteriovenous fistula (AVF) dysfunction. We evaluated 84 HD patients with an average follow-up period of 31.3 ± 8.1 months, identifying 8 stenosis (STN) and 17 thrombosis (THR) cases. The association between paired variables was tested with Pearson's coefficient (r) and p-value, whereas the prognostic value on STN and THR was analysed using Cox's regression. The significant independent variables were indentified with an inverse step-wise approach defining the data as hazard ratio (HR). A double-event (Stenosis/Thrombosis) model, function of Body mass index and Waist/hip ratio was used. Arteriovenous fistula survival was assessed with the Kaplan-Meyer curve and the calculations were carried out with Graph-Pad. On univariate analysis, THR showed direct correlation with BMI (r=0.44, p<0.01), W-C (r=0.39, p<0.05) WHR (r=0.37, p<0.01), Hemoglobin (p<0.001), C-Reactive protein (p=0.01), Calcium/Phosforus product (p=0.03), Parathyroid hormone (p=0.03) and inverse with albumin (p<0.001) and systolic blood pressure (p=0.003). On multivariate analysis, BMI variations were not predictive of STN and THR, whereas each unitary WHR and W-C increase was predictive of an increase of risk of events (3.8% and 2.1% respectively). The prognostic power of W-C per STN (HR 1: 1.19; p<0.05) and THR (HR: 1.28; p<0.01) remained significant even after being adjusted to account for traditional risk factors. Abdominal obesity increases the risk of AVF dysfunction. The W-C and WHR parameters, not BMI, emerge as independent STN and THR predictors.

  17. UCHL1 S18Y variant is a risk factor for Parkinson’s disease in Japan

    PubMed Central

    2012-01-01

    Background A recent meta-analysis on the UCHL1 S18Y variant and Parkinson’s disease (PD) showed a significant inverse association between the Y allele and PD; the individual studies included in that meta-analysis, however, have produced conflicting results. We examined the relationship between UCHL1 S18Y single nucleotide polymorphism (SNP) and sporadic PD in Japan. Methods Included were 229 cases within 6 years of onset of PD, defined according to the UK PD Society Brain Bank clinical diagnostic criteria. Controls were 357 inpatients and outpatients without neurodegenerative disease. Adjustment was made for sex, age, region of residence, smoking, and caffeine intake. Results Compared with subjects with the CC or CA genotype of UCHL1 S18Y SNP, those with the AA genotype had a significantly increased risk of sporadic PD: the adjusted OR was 1.57 (95 % CI: 1.06 − 2.31). Compared with subjects with the CC or CA genotype of UCHL1 S18Y and the CC or CT genotype of SNCA SNP rs356220, those with the AA genotype of UCHL1 S18Y and the TT genotype of SNP rs356220 had a significantly increased risk of sporadic PD; the interaction, however, was not significant. Our previous investigation found significant inverse relationships between smoking and caffeine intake and PD in this population. There were no significant interactions between UCHL1 S18Y and smoking or caffeine intake affecting sporadic PD. Conclusions This study reveals that the UCHL1 S18Y variant is a risk factor for sporadic PD. We could not find evidence for interactions affecting sporadic PD between UCHL1 S18Y and SNCA SNP rs356220, smoking, or caffeine intake. PMID:22839974

  18. Do perinatal and early life exposures influence the risk of malignant melanoma? A Northern Ireland birth cohort analysis.

    PubMed

    O'Rorke, M A; Black, C; Murray, L J; Cardwell, C R; Gavin, A T; Cantwell, M M

    2013-03-01

    Intrauterine, early life and maternal exposures may have important consequences for cancer development in later life. The aim of this study was to examine perinatal and birth characteristics with respect to Cutaneous malignant melanoma (CMM) risk. The Northern Ireland Child Health System database was used to examine gestational age adjusted birth weight, infant feeding practices, parental age and socioeconomic factors at birth in relation to CMM risk amongst 447,663 infants delivered between January 1971 and December 1986. Follow-up of histologically verified CMM cases was undertaken from the beginning of 1993 to 31st December 2007. Multivariable adjusted unconditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI) of CMM risk. A total of 276 CMM cases and 440,336 controls contributed to the final analysis. In reference to normal (gestational age-adjusted) weight babies, those heaviest at birth were twice as likely to develop CMM OR 2.4 (95% CI 1.1-5.1). Inverse associations with CMM risk were observed with younger (<25 years) parental age at birth and both a higher birth order and greater household density OR 0.61 (95% CI 0.37-0.99) and OR 0.56 (95% CI 0.30-1.0) respectively. This large study of early onset melanoma supports a positive association with higher birth weight (imperatively gestational age adjusted) and CMM risk which may be related to factors which drive intrauterine foetal growth. Strong inverse associations observed with higher birth order and household density suggest that early-life immune modulation may confer protection; findings which warrant further investigation in prospective analyses. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Association between adolescent tobacco, alcohol and illicit drug use and individual and environmental resilience protective factors.

    PubMed

    Hodder, Rebecca Kate; Freund, Megan; Bowman, Jenny; Wolfenden, Luke; Gillham, Karen; Dray, Julia; Wiggers, John

    2016-11-25

    Research suggests that individual and environmental resilience protective factors may be associated with adolescent substance use; however, the associations between a broad range of such factors and use of various types of substances have not been examined. The study aimed to determine the association between a comprehensive range of adolescent individual and environmental resilience protective factors and measures of tobacco, alcohol and illicit substance use. Cross-sectional study. 32 Australian secondary schools. Grade 7-10 students (aged 11-17 years). Data regarding 14 student individual and environmental resilience protective factors and seven substance use measures (tobacco, alcohol, marijuana, other illicit drug use) were obtained via an online self-report survey. Adjusted multivariate logistic regression analyses examined the association between all student resilience protective factors and seven substance use measures. Inverse univariate associations were found for 94 of 98 relationships examined (n=10 092). Multivariate analyses found: consistent inverse associations between 2 of 14 protective factors and all substance use measures ('goals and aspirations', 'prosocial peers'); inverse associations between 4 protective factors with multiple substance use measures ('home support' (5 of 7), 'school support' (3 of 7), 'self-awareness' (2 of 7), 'community meaningful participation' (2 of 7)); positive associations between 2 resilience protective factors with multiple measures of substance use ('community support' (3 of 7), 'peer caring relationships' (5 of 7)) and 6 protective factors not to be associated with any substance use measure. Despite individual relationships between the majority of resilience protective factors and substance use types, the protective benefit of such factors for adolescent substance use was limited to only a small number of such factors when considered collectively. Such results suggest that interventions seeking to reduce adolescent substance use may need to target specific protective factors to address specific types of substance use. ACTRN12611000606987, Results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  20. Deep sequencing with intronic capture enables identification of an APC exon 10 inversion in a patient with polyposis.

    PubMed

    Shirts, Brian H; Salipante, Stephen J; Casadei, Silvia; Ryan, Shawnia; Martin, Judith; Jacobson, Angela; Vlaskin, Tatyana; Koehler, Karen; Livingston, Robert J; King, Mary-Claire; Walsh, Tom; Pritchard, Colin C

    2014-10-01

    Single-exon inversions have rarely been described in clinical syndromes and are challenging to detect using Sanger sequencing. We report the case of a 40-year-old woman with adenomatous colon polyps too numerous to count and who had a complex inversion spanning the entire exon 10 in APC (the gene encoding for adenomatous polyposis coli), causing exon skipping and resulting in a frameshift and premature protein truncation. In this study, we employed complete APC gene sequencing using high-coverage next-generation sequencing by ColoSeq, analysis with BreakDancer and SLOPE software, and confirmatory transcript analysis. ColoSeq identified a complex small genomic rearrangement consisting of an inversion that results in translational skipping of exon 10 in the APC gene. This mutation would not have been detected by traditional sequencing or gene-dosage methods. We report a case of adenomatous polyposis resulting from a complex single-exon inversion. Our report highlights the benefits of large-scale sequencing methods that capture intronic sequences with high enough depth of coverage-as well as the use of informatics tools-to enable detection of small pathogenic structural rearrangements.

  1. Real-Time Wing-Vortex and Pressure Distribution Estimation on Wings Via Displacements and Strains in Unsteady and Transitional Flight Conditions

    DTIC Science & Technology

    2016-09-07

    approach in co simulation with fluid-dynamics solvers is used. An original variational formulation is developed for the inverse problem of...by the inverse solution meshing. The same approach is used to map the structural and fluid interface kinematics and loads during the fluid structure...co-simulation. The inverse analysis is verified by reconstructing the deformed solution obtained with a corresponding direct formulation, based on

  2. Weibull Analysis and Area Scaling for Infrared Window Materials (U)

    DTIC Science & Technology

    2016-08-01

    the strength of a window scales inversely with the size of the window. This report was reviewed for technical accuracy by Howard Poisl, Thomas M...strength of a window scales inversely with the size of the window. Test data are given for aluminum oxynitride (ALON), calcium fluoride, chemical vapor...failure of an optical window in the absence of slow crack growth. This report illustrates how the strength of a window scales inversely with the size of

  3. Comparison of microCT and an inverse finite element approach for biomechanical analysis: Results in a MSC therapeutic system for fracture healing

    PubMed Central

    Weis, Jared A.; Granero-Moltó, Froilán; Myers, Timothy J.; Longobardi, Lara; Spagnoli, Anna; Miga, Michael I.

    2013-01-01

    An important concern in the study of fracture healing is the ability to assess mechanical integrity in response to candidate therapeutics in small-animal systems. In recent reports, it has been proposed that microCT image-derived densitometric parameters could be used as a surrogate for mechanical property assessment. Recently, we have proposed an inverse methodology that iteratively reconstructs the modulus of elasticity of the lumped soft callus/hard callus region by integrating both intrinsic mechanical property (from biomechanical testing) and geometrical information (from microCT) within an inverse finite element analysis (FEA) to define a callus quality measure. In this paper, data from a therapeutic system involving mesenchymal stem cells is analyzed within the context of comparing traditional microCT densitometric and mechanical property metrics. In addition, a novel multi-parameter regression microCT parameter is analyzed as well as our inverse FEA metric. The results demonstrate that the inverse FEA approach was the only metric to successfully detect both longitudinal and therapeutic responses. While the most promising microCT-based metrics were adequate at early healing states, they failed to track late-stage mechanical integrity. In addition, our analysis added insight to the role of MSCs by demonstrating accelerated healing and was the only metric to demonstrate therapeutic benefits at late-stage healing. In conclusion, the work presented here indicates that microCT densitometric parameters are an incomplete surrogate for mechanical integrity. Additionally, our inverse FEA approach is shown to be very sensitive and may provide a first-step towards normalizing the often challenging process of assessing mechanical integrity of healing fractures. PMID:22766379

  4. Inverse Transformation: Unleashing Spatially Heterogeneous Dynamics with an Alternative Approach to XPCS Data Analysis.

    PubMed

    Andrews, Ross N; Narayanan, Suresh; Zhang, Fan; Kuzmenko, Ivan; Ilavsky, Jan

    2018-02-01

    X-ray photon correlation spectroscopy (XPCS), an extension of dynamic light scattering (DLS) in the X-ray regime, detects temporal intensity fluctuations of coherent speckles and provides scattering vector-dependent sample dynamics at length scales smaller than DLS. The penetrating power of X-rays enables probing dynamics in a broad array of materials with XPCS, including polymers, glasses and metal alloys, where attempts to describe the dynamics with a simple exponential fit usually fails. In these cases, the prevailing XPCS data analysis approach employs stretched or compressed exponential decay functions (Kohlrausch functions), which implicitly assume homogeneous dynamics. In this paper, we propose an alternative analysis scheme based upon inverse Laplace or Gaussian transformation for elucidating heterogeneous distributions of dynamic time scales in XPCS, an approach analogous to the CONTIN algorithm widely accepted in the analysis of DLS from polydisperse and multimodal systems. Using XPCS data measured from colloidal gels, we demonstrate the inverse transform approach reveals hidden multimodal dynamics in materials, unleashing the full potential of XPCS.

  5. Inverse Transformation: Unleashing Spatially Heterogeneous Dynamics with an Alternative Approach to XPCS Data Analysis

    PubMed Central

    Andrews, Ross N.; Narayanan, Suresh; Zhang, Fan; Kuzmenko, Ivan; Ilavsky, Jan

    2018-01-01

    X-ray photon correlation spectroscopy (XPCS), an extension of dynamic light scattering (DLS) in the X-ray regime, detects temporal intensity fluctuations of coherent speckles and provides scattering vector-dependent sample dynamics at length scales smaller than DLS. The penetrating power of X-rays enables probing dynamics in a broad array of materials with XPCS, including polymers, glasses and metal alloys, where attempts to describe the dynamics with a simple exponential fit usually fails. In these cases, the prevailing XPCS data analysis approach employs stretched or compressed exponential decay functions (Kohlrausch functions), which implicitly assume homogeneous dynamics. In this paper, we propose an alternative analysis scheme based upon inverse Laplace or Gaussian transformation for elucidating heterogeneous distributions of dynamic time scales in XPCS, an approach analogous to the CONTIN algorithm widely accepted in the analysis of DLS from polydisperse and multimodal systems. Using XPCS data measured from colloidal gels, we demonstrate the inverse transform approach reveals hidden multimodal dynamics in materials, unleashing the full potential of XPCS. PMID:29875506

  6. Coffee Consumption and Risk of Biliary Tract Cancers and Liver Cancer: A Dose-Response Meta-Analysis of Prospective Cohort Studies.

    PubMed

    Godos, Justyna; Micek, Agnieszka; Marranzano, Marina; Salomone, Federico; Rio, Daniele Del; Ray, Sumantra

    2017-08-28

    A meta-analysis was conducted to summarize the evidence from prospective cohort and case-control studies regarding the association between coffee intake and biliary tract cancer (BTC) and liver cancer risk. Eligible studies were identified by searches of PubMed and EMBASE databases from the earliest available online indexing year to March 2017. The dose-response relationship was assessed by a restricted cubic spline model and multivariate random-effect meta-regression. A stratified and subgroup analysis by smoking status and hepatitis was performed to identify potential confounding factors. We identified five studies on BTC risk and 13 on liver cancer risk eligible for meta-analysis. A linear dose-response meta-analysis did not show a significant association between coffee consumption and BTC risk. However, there was evidence of inverse correlation between coffee consumption and liver cancer risk. The association was consistent throughout the various potential confounding factors explored including smoking status, hepatitis, etc. Increasing coffee consumption by one cup per day was associated with a 15% reduction in liver cancer risk (RR 0.85; 95% CI 0.82 to 0.88). The findings suggest that increased coffee consumption is associated with decreased risk of liver cancer, but not BTC.

  7. Coffee Consumption and Risk of Biliary Tract Cancers and Liver Cancer: A Dose–Response Meta-Analysis of Prospective Cohort Studies

    PubMed Central

    Micek, Agnieszka; Marranzano, Marina; Ray, Sumantra

    2017-01-01

    Background: A meta-analysis was conducted to summarize the evidence from prospective cohort and case-control studies regarding the association between coffee intake and biliary tract cancer (BTC) and liver cancer risk. Methods: Eligible studies were identified by searches of PubMed and EMBASE databases from the earliest available online indexing year to March 2017. The dose–response relationship was assessed by a restricted cubic spline model and multivariate random-effect meta-regression. A stratified and subgroup analysis by smoking status and hepatitis was performed to identify potential confounding factors. Results: We identified five studies on BTC risk and 13 on liver cancer risk eligible for meta-analysis. A linear dose–response meta-analysis did not show a significant association between coffee consumption and BTC risk. However, there was evidence of inverse correlation between coffee consumption and liver cancer risk. The association was consistent throughout the various potential confounding factors explored including smoking status, hepatitis, etc. Increasing coffee consumption by one cup per day was associated with a 15% reduction in liver cancer risk (RR 0.85; 95% CI 0.82 to 0.88). Conclusions: The findings suggest that increased coffee consumption is associated with decreased risk of liver cancer, but not BTC. PMID:28846640

  8. Assessment of the apparent bending stiffness and damping of multilayer plates; modelling and experiment

    NASA Astrophysics Data System (ADS)

    Ege, Kerem; Roozen, N. B.; Leclère, Quentin; Rinaldi, Renaud G.

    2018-07-01

    In the context of aeronautics, automotive and construction applications, the design of light multilayer plates with optimized vibroacoustical damping and isolation performances remains a major industrial challenge and a hot topic of research. This paper focuses on the vibrational behavior of three-layered sandwich composite plates in a broad-band frequency range. Several aspects are studied through measurement techniques and analytical modelling of a steel/polymer/steel plate sandwich system. A contactless measurement of the velocity field of plates using a scanning laser vibrometer is performed, from which the equivalent single layer complex rigidity (apparent bending stiffness and apparent damping) in the mid/high frequency ranges is estimated. The results are combined with low/mid frequency estimations obtained with a high-resolution modal analysis method so that the frequency dependent equivalent Young's modulus and equivalent loss factor of the composite plate are identified for the whole [40 Hz-20 kHz] frequency band. The results are in very good agreement with an equivalent single layer analytical modelling based on wave propagation analysis (model of Guyader). The comparison with this model allows identifying the frequency dependent complex modulus of the polymer core layer through inverse resolution. Dynamical mechanical analysis measurements are also performed on the polymer layer alone and compared with the values obtained through the inverse method. Again, a good agreement between these two estimations over the broad-band frequency range demonstrates the validity of the approach.

  9. Oil core microcapsules by inverse gelation technique.

    PubMed

    Martins, Evandro; Renard, Denis; Davy, Joëlle; Marquis, Mélanie; Poncelet, Denis

    2015-01-01

    A promising technique for oil encapsulation in Ca-alginate capsules by inverse gelation was proposed by Abang et al. This method consists of emulsifying calcium chloride solution in oil and then adding it dropwise in an alginate solution to produce Ca-alginate capsules. Spherical capsules with diameters around 3 mm were produced by this technique, however the production of smaller capsules was not demonstrated. The objective of this study is to propose a new method of oil encapsulation in a Ca-alginate membrane by inverse gelation. The optimisation of the method leads to microcapsules with diameters around 500 μm. In a search of microcapsules with improved diffusion characteristics, the size reduction is an essential factor to broaden the applications in food, cosmetics and pharmaceuticals areas. This work contributes to a better understanding of the inverse gelation technique and allows the production of microcapsules with a well-defined shell-core structure.

  10. Long-term Changes in Extreme Air Pollution Meteorology and the Implications for Air Quality.

    PubMed

    Hou, Pei; Wu, Shiliang

    2016-03-31

    Extreme air pollution meteorological events, such as heat waves, temperature inversions and atmospheric stagnation episodes, can significantly affect air quality. Based on observational data, we have analyzed the long-term evolution of extreme air pollution meteorology on the global scale and their potential impacts on air quality, especially the high pollution episodes. We have identified significant increasing trends for the occurrences of extreme air pollution meteorological events in the past six decades, especially over the continental regions. Statistical analysis combining air quality data and meteorological data further indicates strong sensitivities of air quality (including both average air pollutant concentrations and high pollution episodes) to extreme meteorological events. For example, we find that in the United States the probability of severe ozone pollution when there are heat waves could be up to seven times of the average probability during summertime, while temperature inversions in wintertime could enhance the probability of severe particulate matter pollution by more than a factor of two. We have also identified significant seasonal and spatial variations in the sensitivity of air quality to extreme air pollution meteorology.

  11. Airborne remote sensing and in situ measurements of atmospheric CO2 to quantify point source emissions

    NASA Astrophysics Data System (ADS)

    Krings, Thomas; Neininger, Bruno; Gerilowski, Konstantin; Krautwurst, Sven; Buchwitz, Michael; Burrows, John P.; Lindemann, Carsten; Ruhtz, Thomas; Schüttemeyer, Dirk; Bovensmann, Heinrich

    2018-02-01

    Reliable techniques to infer greenhouse gas emission rates from localised sources require accurate measurement and inversion approaches. In this study airborne remote sensing observations of CO2 by the MAMAP instrument and airborne in situ measurements are used to infer emission estimates of carbon dioxide released from a cluster of coal-fired power plants. The study area is complex due to sources being located in close proximity and overlapping associated carbon dioxide plumes. For the analysis of in situ data, a mass balance approach is described and applied, whereas for the remote sensing observations an inverse Gaussian plume model is used in addition to a mass balance technique. A comparison between methods shows that results for all methods agree within 10 % or better with uncertainties of 10 to 30 % for cases in which in situ measurements were made for the complete vertical plume extent. The computed emissions for individual power plants are in agreement with results derived from emission factors and energy production data for the time of the overflight.

  12. Husimi function and phase-space analysis of bilayer quantum Hall systems at ν = 2/λ

    NASA Astrophysics Data System (ADS)

    Calixto, M.; Peón-Nieto, C.

    2018-05-01

    We propose localization measures in phase space of the ground state of bilayer quantum Hall systems at fractional filling factors , to characterize the three quantum phases (shortly denoted by spin, canted and ppin) for arbitrary -isospin λ. We use a coherent state (Bargmann) representation of quantum states, as holomorphic functions in the 8-dimensional Grassmannian phase-space (a higher-dimensional generalization of the Haldane’s 2-dimensional sphere ). We quantify the localization (inverse volume) of the ground state wave function in phase-space throughout the phase diagram (i.e. as a function of Zeeman, tunneling, layer distance, etc, control parameters) with the Husimi function second moment, a kind of inverse participation ratio that behaves as an order parameter. Then we visualize the different ground state structure in phase space of the three quantum phases, the canted phase displaying a much higher delocalization (a Schrödinger cat structure) than the spin and ppin phases, where the ground state is highly coherent. We find a good agreement between analytic (variational) and numeric diagonalization results.

  13. ShiftNMFk 1.2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alexandrov, Boian S.; Vesselinov, Velimir V.; Stanev, Valentin

    The ShiftNMFk1.2 code, or as we call it, GreenNMFk, represents a hybrid algorithm combining unsupervised adaptive machine learning and Green's function inverse method. GreenNMFk allows an efficient and high performance de-mixing and feature extraction of a multitude of nonnegative signals that change their shape propagating through the medium. The signals are mixed and recorded by a network of uncorrelated sensors. The code couples Non-negative Matrix Factorization (NMF) and inverse-analysis Green's functions method. GreenNMF synergistically performs decomposition of the recorded mixtures, finds the number of the unknown sources and uses the Green's function of the governing partial differential equation to identifymore » the unknown sources and their charecteristics. GreenNMF can be applied directly to any problem controlled by a known partial-differential parabolic equation where mixtures of an unknown number of sources are measured at multiple locations. Full GreenNMFk method is a subject LANL U.S. Patent application S133364.000 August, 2017. The ShiftNMFk 1.2 version here is a toy version of this method that can work with a limited number of unknown sources (4 or less).« less

  14. Age-related differences in early novelty processing: Using PCA to parse the overlapping anterior P2 and N2 components

    PubMed Central

    Daffner, Kirk R.; Alperin, Brittany R.; Mott, Katherine K.; Tusch, Erich; Holcomb, Phillip J.

    2015-01-01

    Previous work demonstrated age-associated increases in the anterior P2 and age-related decreases in the anterior N2 in response to novel stimuli. Principal component analysis (PCA) was used to determine if the inverse relationship between these components was due to their temporal and spatial overlap. PCA revealed an early anterior P2, sensitive to task relevance, and a late anterior P2, responsive to novelty, both exhibiting age-related amplitude increases. A PCA factor representing the anterior N2, sensitive to novelty, exhibited age-related amplitude decreases. The late P2 and N2 to novels inversely correlated. Larger late P2 amplitude to novels was associated with better behavioral performance. Age-related differences in the anterior P2 and N2 to novel stimuli likely represent age-associated changes in independent cognitive operations. Enhanced anterior P2 activity (indexing augmentation in motivational salience) may be a compensatory mechanism for diminished anterior N2 activity (indexing reduced ability of older adults to process ambiguous representations). PMID:25596483

  15. CXCR4 and CXCL12 are inversely expressed in colorectal cancer cells and modulate cancer cell migration, invasion and MMP-9 activation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brand, Stephan; Dambacher, Julia; Beigel, Florian

    2005-10-15

    Colorectal cancer (CRC) is characterized by a distinct metastatic pattern resembling chemokine-induced leukocyte trafficking. This prompted us to investigate expression, signal transduction and specific functions of the chemokine receptor CXCR4 in CRC cells and metastases. Using RT-PCR analysis and Western blotting, we demonstrated CXCR4 and CXCL12 expression in CRC and CRC metastases. Cell differentiation increases CXCL12 mRNA levels. Moreover, CXCR4 and its ligand are inversely expressed in CRC cell lines with high CXCR4 and low or not detectable CXCL12 expression. CXCL12 activates ERK-1/2, SAPK/JNK kinases, Akt and matrix metalloproteinase-9. These CXCL12-induced signals mediate reorganization of the actin cytoskeleton resulting inmore » increased cancer cell migration and invasion. Moreover, CXCL12 increases vascular endothelial growth factor (VEGF) expression and cell proliferation but has no effect on CRC apoptosis. Therefore, the CXCL12/CXCR4 system is an important mediator of invasion and metastasis of CXCR4 expressing CRC cells.« less

  16. [Research on the method of interference correction for nondispersive infrared multi-component gas analysis].

    PubMed

    Sun, You-Wen; Liu, Wen-Qing; Wang, Shi-Mei; Huang, Shu-Hua; Yu, Xiao-Man

    2011-10-01

    A method of interference correction for nondispersive infrared multi-component gas analysis was described. According to the successive integral gas absorption models and methods, the influence of temperature and air pressure on the integral line strengths and linetype was considered, and based on Lorentz detuning linetypes, the absorption cross sections and response coefficients of H2O, CO2, CO, and NO on each filter channel were obtained. The four dimension linear regression equations for interference correction were established by response coefficients, the absorption cross interference was corrected by solving the multi-dimensional linear regression equations, and after interference correction, the pure absorbance signal on each filter channel was only controlled by the corresponding target gas concentration. When the sample cell was filled with gas mixture with a certain concentration proportion of CO, NO and CO2, the pure absorbance after interference correction was used for concentration inversion, the inversion concentration error for CO2 is 2.0%, the inversion concentration error for CO is 1.6%, and the inversion concentration error for NO is 1.7%. Both the theory and experiment prove that the interference correction method proposed for NDIR multi-component gas analysis is feasible.

  17. Chromosomal Inversions, Natural Selection and Adaptation in the Malaria Vector Anopheles funestus

    PubMed Central

    Ayala, Diego; Fontaine, Michael C.; Cohuet, Anna; Fontenille, Didier; Vitalis, Renaud; Simard, Frédéric

    2011-01-01

    Chromosomal polymorphisms, such as inversions, are presumably involved in the rapid adaptation of populations to local environmental conditions. Reduced recombination between alternative arrangements in heterozygotes may protect sets of locally adapted genes, promoting ecological divergence and potentially leading to reproductive isolation and speciation. Through a comparative analysis of chromosomal inversions and microsatellite marker polymorphisms, we hereby present biological evidence that strengthens this view in the mosquito Anopheles funestus s.s, one of the most important and widespread malaria vectors in Africa. Specimens were collected across a wide range of geographical, ecological, and climatic conditions in Cameroon. We observed a sharp contrast between population structure measured at neutral microsatellite markers and at chromosomal inversions. Microsatellite data detected only a weak signal for population structuring among geographical zones (FST < 0.013, P < 0.01). By contrast, strong differentiation among ecological zones was revealed by chromosomal inversions (FST > 0.190, P < 0.01). Using standardized estimates of FST, we show that inversions behave at odds with neutral expectations strongly suggesting a role of environmental selection in shaping their distribution. We further demonstrate through canonical correspondence analysis that heterogeneity in eco-geographical variables measured at specimen sampling sites explained 89% of chromosomal variance in A. funestus. These results are in agreement with a role of chromosomal inversions in ecotypic adaptation in this species. We argue that this widespread mosquito represents an interesting model system for the study of chromosomal speciation mechanisms and should provide ample opportunity for comparative studies on the evolution of reproductive isolation and speciation in major human malaria vectors. PMID:20837604

  18. Time Domain Radar Laboratory Operating System Development and Transient EM Analysis.

    DTIC Science & Technology

    1981-09-01

    polarization of the return, arg used. Other similar methods use amplitude and phase differences or special properties of Rayleigh region scattering. All these...3ptias Inverse Scattering ... 19 2. "!xact" Inverse Scattering !Nethod .. 20 3. Other Methods ................... 21 C. REVIEW OF TDRL PROGRESS AT SPS...explicit independant variable in.most methods . In the past, frequency domain analysis has been the primary means of analyzing aan-monochromatic EM

  19. Improving resolution of crosswell seismic section based on time-frequency analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Luo, H.; Li, Y.

    1994-12-31

    According to signal theory, to improve resolution of seismic section is to extend high-frequency band of seismic signal. In cross-well section, sonic log can be regarded as a reliable source providing high-frequency information to the trace near the borehole. In such case, what to do is to introduce this high-frequency information into the whole section. However, neither traditional deconvolution algorithms nor some new inversion methods such as BCI (Broad Constraint Inversion) are satisfied because of high-frequency noise and nonuniqueness of inversion results respectively. To overcome their disadvantages, this paper presents a new algorithm based on Time-Frequency Analysis (TFA) technology whichmore » has been increasingly received much attention as an useful signal analysis too. Practical applications show that the new method is a stable scheme to improve resolution of cross-well seismic section greatly without decreasing Signal to Noise Ratio (SNR).« less

  20. An inverse method for the aerodynamic design of three-dimensional aircraft engine nacelles

    NASA Technical Reports Server (NTRS)

    Bell, R. A.; Cedar, R. D.

    1991-01-01

    A fast, efficient and user friendly inverse design system for 3-D nacelles was developed. The system is a product of a 2-D inverse design method originally developed at NASA-Langley and the CFL3D analysis code which was also developed at NASA-Langley and modified for nacelle analysis. The design system uses a predictor/corrector design approach in which an analysis code is used to calculate the flow field for an initial geometry, the geometry is then modified based on the difference between the calculated and target pressures. A detailed discussion of the design method, the process of linking it to the modified CFL3D solver and its extension to 3-D is presented. This is followed by a number of examples of the use of the design system for the design of both axisymmetric and 3-D nacelles.

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