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Sample records for admixture mapping scans

  1. The admixture structure and genetic variation of the archipelago of Cape Verde and its implications for admixture mapping studies.

    Directory of Open Access Journals (Sweden)

    Sandra Beleza

    Full Text Available Recently admixed populations offer unique opportunities for studying human history and for elucidating the genetic basis of complex traits that differ in prevalence between human populations. Historical records, classical protein markers, and preliminary genetic data indicate that the Cape Verde islands in West Africa are highly admixed and primarily descended from European males and African females. However, little is known about the variation in admixture levels, admixture dynamics and genetic diversity across the islands, or about the potential of Cape Verde for admixture mapping studies. We have performed a detailed analysis of phenotypic and genetic variation in Cape Verde based on objective skin color measurements, socio-economic status (SES evaluations and data for 50 autosomal, 34 X-chromosome, and 21 non-recombinant Y-chromosome (NRY markers in 845 individuals from six islands of the archipelago. We find extensive genetic admixture between European and African ancestral populations (mean West African ancestry = 0.57, sd = 0.08, with individual African ancestry proportions varying considerably among the islands. African ancestry proportions calculated with X and Y-chromosome markers confirm that the pattern of admixture has been sex-biased. The high-resolution NRY-STRs reveal additional patterns of variation among the islands that are most consistent with differentiation after admixture. The differences in the autosomal admixture proportions are clearly evident in the skin color distribution across the islands (Pearson r = 0.54, P-value<2e-16. Despite this strong correlation, there are significant interactions between SES and skin color that are independent of the relationship between skin color and genetic ancestry. The observed distributions of admixture, genetic variation and skin color and the relationship of skin color with SES relate to historical and social events taking place during the settlement history of Cape Verde, and have

  2. Admixture Mapping Identifies a Quantitative Trait Locus Associated with FEV1/FVC in the COPDGene Study

    OpenAIRE

    Parker, Margaret M.; Foreman, Marilyn G; Abel, Haley J.; Rasika A Mathias; Hetmanksi, Jacqueline B.; Crapo, James D.; Silverman, Edwin K.; Terri H Beaty

    2014-01-01

    African Americans are admixed with genetic contributions from European and African ancestral populations. Admixture mapping leverages this information to map genes influencing differential disease risk across populations. We performed admixture and association mapping in 3300 African American current or former smokers from the COPDGene Study. We analyzed estimated local ancestry and SNP genotype information to identify regions associated with FEV1/FVC, the ratio of forced expiratory volume in...

  3. Admixture mapping identifies introgressed genomic regions in North American canids.

    Science.gov (United States)

    vonHoldt, Bridgett M; Kays, Roland; Pollinger, John P; Wayne, Robert K

    2016-06-01

    Hybrid zones typically contain novel gene combinations that can be tested by natural selection in a unique genetic context. Parental haplotypes that increase fitness can introgress beyond the hybrid zone, into the range of parental species. We used the Affymetrix canine SNP genotyping array to identify genomic regions tagged by multiple ancestry informative markers that are more frequent in an admixed population than expected. We surveyed a hybrid zone formed in the last 100 years as coyotes expanded their range into eastern North America. Concomitant with expansion, coyotes hybridized with wolves and some populations became more wolflike, such that coyotes in the northeast have the largest body size of any coyote population. Using a set of 3102 ancestry informative markers, we identified 60 differentially introgressed regions in 44 canines across this admixture zone. These regions are characterized by an excess of exogenous ancestry and, in northeastern coyotes, are enriched for genes affecting body size and skeletal proportions. Further, introgressed wolf-derived alleles have penetrated into Southern US coyote populations. Because no wolves currently exist in this area, these alleles are unlikely to have originated from recent hybridization. Instead, they probably originated from intraspecific gene flow or ancient admixture. We show that grey wolf and coyote admixture has far-reaching effects and, in addition to phenotypically transforming admixed populations, allows for the differential movement of alleles from different parental species to be tested in new genomic backgrounds. PMID:27106273

  4. Genome-wide Scan of 29,141 African Americans Finds No Evidence of Directional Selection since Admixture

    OpenAIRE

    Bhatia, Gaurav; Tandon, Arti; Patterson, Nick; Aldrich, Melinda C.; Ambrosone, Christine B.; Amos, Christopher; Bandera, Elisa V.; Berndt, Sonja I.; Bernstein, Leslie; Blot, William J.; Bock, Cathryn H.; Caporaso, Neil; Casey, Graham; Deming, Sandra L.; Diver, W. Ryan

    2014-01-01

    The extent of recent selection in admixed populations is currently an unresolved question. We scanned the genomes of 29,141 African Americans and failed to find any genome-wide-significant deviations in local ancestry, indicating no evidence of selection influencing ancestry after admixture. A recent analysis of data from 1,890 African Americans reported that there was evidence of selection in African Americans after their ancestors left Africa, both before and after admixture. Selection afte...

  5. High-resolution gene mapping using admixture linkage disequilibrium

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This note reports simulation study on the rate of decay in linkage dis equilibrium (LD) in mixed populations over multiple discrete generations and explores the usefulness of the LD analysis in high-resolution gene mapping. The results indicate that the smaller the recombination fraction and the fewer generati ons since admixtureevent, the higher power of the approach in gene mapping. The expected estimate of recombination fraction would give an estimate that is slig htly biased upwards, if relevant genes are in tight linkage. The estimated recom bination fraction is usually larger than the true value within 2-5 generations. From generations 10-20, the mean estimates are in good agreement with the true value. The method presented here enables estimation of means and corresponding confidence intervals of the recombination fraction at any number of generations.

  6. Genome-wide scan of 29,141 African Americans finds no evidence of directional selection since admixture.

    Science.gov (United States)

    Bhatia, Gaurav; Tandon, Arti; Patterson, Nick; Aldrich, Melinda C; Ambrosone, Christine B; Amos, Christopher; Bandera, Elisa V; Berndt, Sonja I; Bernstein, Leslie; Blot, William J; Bock, Cathryn H; Caporaso, Neil; Casey, Graham; Deming, Sandra L; Diver, W Ryan; Gapstur, Susan M; Gillanders, Elizabeth M; Harris, Curtis C; Henderson, Brian E; Ingles, Sue A; Isaacs, William; De Jager, Phillip L; John, Esther M; Kittles, Rick A; Larkin, Emma; McNeill, Lorna H; Millikan, Robert C; Murphy, Adam; Neslund-Dudas, Christine; Nyante, Sarah; Press, Michael F; Rodriguez-Gil, Jorge L; Rybicki, Benjamin A; Schwartz, Ann G; Signorello, Lisa B; Spitz, Margaret; Strom, Sara S; Tucker, Margaret A; Wiencke, John K; Witte, John S; Wu, Xifeng; Yamamura, Yuko; Zanetti, Krista A; Zheng, Wei; Ziegler, Regina G; Chanock, Stephen J; Haiman, Christopher A; Reich, David; Price, Alkes L

    2014-10-01

    The extent of recent selection in admixed populations is currently an unresolved question. We scanned the genomes of 29,141 African Americans and failed to find any genome-wide-significant deviations in local ancestry, indicating no evidence of selection influencing ancestry after admixture. A recent analysis of data from 1,890 African Americans reported that there was evidence of selection in African Americans after their ancestors left Africa, both before and after admixture. Selection after admixture was reported on the basis of deviations in local ancestry, and selection before admixture was reported on the basis of allele-frequency differences between African Americans and African populations. The local-ancestry deviations reported by the previous study did not replicate in our very large sample, and we show that such deviations were expected purely by chance, given the number of hypotheses tested. We further show that the previous study's conclusion of selection in African Americans before admixture is also subject to doubt. This is because the FST statistics they used were inflated and because true signals of unusual allele-frequency differences between African Americans and African populations would be best explained by selection that occurred in Africa prior to migration to the Americas.

  7. Genome-wide Scan of 29,141 African Americans Finds No Evidence of Directional Selection since Admixture

    Science.gov (United States)

    Bhatia, Gaurav; Tandon, Arti; Patterson, Nick; Aldrich, Melinda C.; Ambrosone, Christine B.; Amos, Christopher; Bandera, Elisa V.; Berndt, Sonja I.; Bernstein, Leslie; Blot, William J.; Bock, Cathryn H.; Caporaso, Neil; Casey, Graham; Deming, Sandra L.; Diver, W. Ryan; Gapstur, Susan M.; Gillanders, Elizabeth M.; Harris, Curtis C.; Henderson, Brian E.; Ingles, Sue A.; Isaacs, William; De Jager, Phillip L.; John, Esther M.; Kittles, Rick A.; Larkin, Emma; McNeill, Lorna H.; Millikan, Robert C.; Murphy, Adam; Neslund-Dudas, Christine; Nyante, Sarah; Press, Michael F.; Rodriguez-Gil, Jorge L.; Rybicki, Benjamin A.; Schwartz, Ann G.; Signorello, Lisa B.; Spitz, Margaret; Strom, Sara S.; Tucker, Margaret A.; Wiencke, John K.; Witte, John S.; Wu, Xifeng; Yamamura, Yuko; Zanetti, Krista A.; Zheng, Wei; Ziegler, Regina G.; Chanock, Stephen J.; Haiman, Christopher A.; Reich, David; Price, Alkes L.

    2014-01-01

    The extent of recent selection in admixed populations is currently an unresolved question. We scanned the genomes of 29,141 African Americans and failed to find any genome-wide-significant deviations in local ancestry, indicating no evidence of selection influencing ancestry after admixture. A recent analysis of data from 1,890 African Americans reported that there was evidence of selection in African Americans after their ancestors left Africa, both before and after admixture. Selection after admixture was reported on the basis of deviations in local ancestry, and selection before admixture was reported on the basis of allele-frequency differences between African Americans and African populations. The local-ancestry deviations reported by the previous study did not replicate in our very large sample, and we show that such deviations were expected purely by chance, given the number of hypotheses tested. We further show that the previous study’s conclusion of selection in African Americans before admixture is also subject to doubt. This is because the FST statistics they used were inflated and because true signals of unusual allele-frequency differences between African Americans and African populations would be best explained by selection that occurred in Africa prior to migration to the Americas. PMID:25242497

  8. Admixture mapping of end stage kidney disease genetic susceptibility using estimated mutual information ancestry informative markers

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    Geiger Dan

    2010-10-01

    Full Text Available Abstract Background The question of a genetic contribution to the higher prevalence and incidence of end stage kidney disease (ESKD among African Americans (AA remained unresolved, until recent findings using admixture mapping pointed to the association of a genomic locus on chromosome 22 with this disease phenotype. In the current study we utilize this example to demonstrate the utility of applying a multi-step admixture mapping approach. Methods A multi-step case only admixture mapping study, consisted of the following steps was designed: 1 Assembly of the sample dataset (ESKD AA; 2 Design of the estimated mutual information ancestry informative markers (n = 2016 screening panel 3; Genotyping the sample set whose size was determined by a power analysis (n = 576 appropriate for the initial screening panel; 4 Inference of local ancestry for each individual and identification of regions with increased AA ancestry using two different ancestry inference statistical approaches; 5 Enrichment of the initial screening panel; 6 Power analysis of the enriched panel 7 Genotyping of additional samples. 8 Re-analysis of the genotyping results to identify a genetic risk locus. Results The initial screening phase yielded a significant peak using the ADMIXMAP ancestry inference program applying case only statistics. Subgroup analysis of 299 ESKD patients with no history of diabetes yielded peaks using both the ANCESTRYMAP and ADMIXMAP ancestry inference programs. The significant peak was found on chromosome 22. Genotyping of additional ancestry informative markers on chromosome 22 that took into account linkage disequilibrium in the ancestral populations, and the addition of samples increased the statistical significance of the finding. Conclusions A multi-step admixture mapping analysis of AA ESKD patients replicated the finding of a candidate risk locus on chromosome 22, contributing to the heightened susceptibility of African Americans to develop non

  9. Rate of decay in admixture linkage disequilibrium and its implication in gene mapping

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Modeling linkage disequilibria (LD) between genes usually observed in admixed natural populations has been shown an effective approach in high-resolution mapping of disease genes in humans. A prerequisite to obtain accurate estimation of recombination fraction between genes at a marker locus and the disease locus using the approach is a reliable prediction of the proportion of the admixture populations. The present study suggested the use of gene frequencies to predict the estimate of the admixture propor-tion based on the observation that the gene frequencies are much more stable quantities than the haplotype frequencies over evolution of the population. In this paper, we advanced the theory and methods by which the decay rate of nonlinear term of LD in admixed population may be used to estimate the recombination fraction between the genes. Theoretical analysis and simulation study indicate that, the larger the difference of gene frequencies between parental populations and the more closely the admixture proportion approaches 0.5, the more important the nonlinear term of the LD in the admixed population, and hence the more informative such admixed populations in the high-resolution gene mapping practice.

  10. A Genomewide Single-Nucleotide–Polymorphism Panel for Mexican American Admixture Mapping

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    Tian, Chao ; Hinds, David A. ; Shigeta, Russell ; Adler, Sharon G. ; Lee, Annette ; Pahl, Madeleine V. ; Silva, Gabriel ; Belmont, John W. ; Hanson, Robert L. ; Knowler, William C. ; Gregersen, Peter K. ; Ballinger, Dennis G. ; Seldin, Michael F. 

    2007-01-01

    For admixture mapping studies in Mexican Americans (MAM), we define a genomewide single-nucleotide–polymorphism (SNP) panel that can distinguish between chromosomal segments of Amerindian (AMI) or European (EUR) ancestry. These studies used genotypes for >400,000 SNPs, defined in EUR and both Pima and Mayan AMI, to define a set of ancestry-informative markers (AIMs). The use of two AMI populations was necessary to remove a subset of SNPs that distinguished genotypes of only one AMI subgroup from EUR genotypes. The AIMs set contained 8,144 SNPs separated by a minimum of 50 kb with only three intermarker intervals >1 Mb and had EUR/AMI FST values >0.30 (mean FST=0.48) and Mayan/Pima FST values <0.05 (mean FST<0.01). Analysis of a subset of these SNP AIMs suggested that this panel may also distinguish ancestry between EUR and other disparate AMI groups, including Quechuan from South America. We show, using realistic simulation parameters that are based on our analyses of MAM genotyping results, that this panel of SNP AIMs provides good power for detecting disease-associated chromosomal segments for genes with modest ethnicity risk ratios. A reduced set of 5,287 SNP AIMs captured almost the same admixture mapping information, but smaller SNP sets showed substantial drop-off in admixture mapping information and power. The results will enable studies of type 2 diabetes, rheumatoid arthritis, and other diseases among which epidemiological studies suggest differences in the distribution of ancestry-associated susceptibility. PMID:17557415

  11. Genome-wide scan of 29,141 African Americans finds no evidence of selection since admixture

    OpenAIRE

    Bhatia, Gaurav; Tandon, Arti; Aldrich, Melinda C.; Ambrosone, Christine B.; Amos, Christopher; Bandera, Elisa V.; Berndt, Sonja I.; Bernstein, Leslie; William J Blot; Bock, Cathryn H.; Caporaso, Neil; Casey, Graham; Deming, Sandra L.; Diver, W Ryan; Gapstur, Susan M

    2013-01-01

    We scanned through the genomes of 29,141 African Americans, searching for loci where the average proportion of African ancestry deviates significantly from the genome-wide average. We failed to find any genome-wide significant deviations, and conclude that any selection in African Americans since admixture is sufficiently weak that it falls below the threshold of our power to detect it using a large sample size. These results stand in contrast to the findings of a recent study of selection in...

  12. Comparison of measures of marker informativeness for ancestry and admixture mapping

    Directory of Open Access Journals (Sweden)

    Ding Lili

    2011-12-01

    Full Text Available Abstract Background Admixture mapping is a powerful gene mapping approach for an admixed population formed from ancestral populations with different allele frequencies. The power of this method relies on the ability of ancestry informative markers (AIMs to infer ancestry along the chromosomes of admixed individuals. In this study, more than one million SNPs from HapMap databases and simulated data have been interrogated in admixed populations using various measures of ancestry informativeness: Fisher Information Content (FIC, Shannon Information Content (SIC, F statistics (FST, Informativeness for Assignment Measure (In, and the Absolute Allele Frequency Differences (delta, δ. The objectives are to compare these measures of informativeness to select SNP markers for ancestry inference, and to determine the accuracy of AIM panels selected by each measure in estimating the contributions of the ancestors to the admixed population. Results FST and In had the highest Spearman correlation and the best agreement as measured by Kappa statistics based on deciles. Although the different measures of marker informativeness performed comparably well, analyses based on the top 1 to 10% ranked informative markers of simulated data showed that In was better in estimating ancestry for an admixed population. Conclusions Although millions of SNPs have been identified, only a small subset needs to be genotyped in order to accurately predict ancestry with a minimal error rate in a cost-effective manner. In this article, we compared various methods for selecting ancestry informative SNPs using simulations as well as SNP genotype data from samples of admixed populations and showed that the In measure estimates ancestry proportion (in an admixed population with lower bias and mean square error.

  13. Admixture mapping of 15,280 African Americans identifies obesity susceptibility loci on chromosomes 5 and X.

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    Ching-Yu Cheng

    2009-05-01

    Full Text Available The prevalence of obesity (body mass index (BMI > or =30 kg/m(2 is higher in African Americans than in European Americans, even after adjustment for socioeconomic factors, suggesting that genetic factors may explain some of the difference. To identify genetic loci influencing BMI, we carried out a pooled analysis of genome-wide admixture mapping scans in 15,280 African Americans from 14 epidemiologic studies. Samples were genotyped at a median of 1,411 ancestry-informative markers. After adjusting for age, sex, and study, BMI was analyzed both as a dichotomized (top 20% versus bottom 20% and a continuous trait. We found that a higher percentage of European ancestry was significantly correlated with lower BMI (rho = -0.042, P = 1.6x10(-7. In the dichotomized analysis, we detected two loci on chromosome X as associated with increased African ancestry: the first at Xq25 (locus-specific LOD = 5.94; genome-wide score = 3.22; case-control Z = -3.94; and the second at Xq13.1 (locus-specific LOD = 2.22; case-control Z = -4.62. Quantitative analysis identified a third locus at 5q13.3 where higher BMI was highly significantly associated with greater European ancestry (locus-specific LOD = 6.27; genome-wide score = 3.46. Further mapping studies with dense sets of markers will be necessary to identify the alleles in these regions of chromosomes X and 5 that may be associated with variation in BMI.

  14. Admixture mapping of 15,280 African Americans identifies obesity susceptibility loci on chromosomes 5 and X.

    Science.gov (United States)

    Cheng, Ching-Yu; Kao, W H Linda; Patterson, Nick; Tandon, Arti; Haiman, Christopher A; Harris, Tamara B; Xing, Chao; John, Esther M; Ambrosone, Christine B; Brancati, Frederick L; Coresh, Josef; Press, Michael F; Parekh, Rulan S; Klag, Michael J; Meoni, Lucy A; Hsueh, Wen-Chi; Fejerman, Laura; Pawlikowska, Ludmila; Freedman, Matthew L; Jandorf, Lina H; Bandera, Elisa V; Ciupak, Gregory L; Nalls, Michael A; Akylbekova, Ermeg L; Orwoll, Eric S; Leak, Tennille S; Miljkovic, Iva; Li, Rongling; Ursin, Giske; Bernstein, Leslie; Ardlie, Kristin; Taylor, Herman A; Boerwinckle, Eric; Zmuda, Joseph M; Henderson, Brian E; Wilson, James G; Reich, David

    2009-05-01

    The prevalence of obesity (body mass index (BMI) > or =30 kg/m(2)) is higher in African Americans than in European Americans, even after adjustment for socioeconomic factors, suggesting that genetic factors may explain some of the difference. To identify genetic loci influencing BMI, we carried out a pooled analysis of genome-wide admixture mapping scans in 15,280 African Americans from 14 epidemiologic studies. Samples were genotyped at a median of 1,411 ancestry-informative markers. After adjusting for age, sex, and study, BMI was analyzed both as a dichotomized (top 20% versus bottom 20%) and a continuous trait. We found that a higher percentage of European ancestry was significantly correlated with lower BMI (rho = -0.042, P = 1.6x10(-7)). In the dichotomized analysis, we detected two loci on chromosome X as associated with increased African ancestry: the first at Xq25 (locus-specific LOD = 5.94; genome-wide score = 3.22; case-control Z = -3.94); and the second at Xq13.1 (locus-specific LOD = 2.22; case-control Z = -4.62). Quantitative analysis identified a third locus at 5q13.3 where higher BMI was highly significantly associated with greater European ancestry (locus-specific LOD = 6.27; genome-wide score = 3.46). Further mapping studies with dense sets of markers will be necessary to identify the alleles in these regions of chromosomes X and 5 that may be associated with variation in BMI.

  15. Admixture Mapping in Lupus Identifies Multiple Functional Variants within IFIH1 Associated with Apoptosis, Inflammation, and Autoantibody Production

    Science.gov (United States)

    Looger, Loren L.; Han, Shizhong; Kim-Howard, Xana; Glenn, Stuart; Adler, Adam; Kelly, Jennifer A.; Niewold, Timothy B.; Gilkeson, Gary S.; Brown, Elizabeth E.; Alarcón, Graciela S.; Edberg, Jeffrey C.; Petri, Michelle; Ramsey-Goldman, Rosalind; Reveille, John D.; Vilá, Luis M.; Freedman, Barry I.; Tsao, Betty P.; Criswell, Lindsey A.; Jacob, Chaim O.; Moore, Jason H.; Vyse, Timothy J.; Langefeld, Carl L.; Guthridge, Joel M.; Gaffney, Patrick M.; Moser, Kathy L.; Scofield, R. Hal; Alarcón-Riquelme, Marta E.; Williams, Scott M.; Merrill, Joan T.; James, Judith A.; Kaufman, Kenneth M.; Kimberly, Robert P.; Harley, John B.; Nath, Swapan K.

    2013-01-01

    Systemic lupus erythematosus (SLE) is an inflammatory autoimmune disease with a strong genetic component. African-Americans (AA) are at increased risk of SLE, but the genetic basis of this risk is largely unknown. To identify causal variants in SLE loci in AA, we performed admixture mapping followed by fine mapping in AA and European-Americans (EA). Through genome-wide admixture mapping in AA, we identified a strong SLE susceptibility locus at 2q22–24 (LOD = 6.28), and the admixture signal is associated with the European ancestry (ancestry risk ratio ∼1.5). Large-scale genotypic analysis on 19,726 individuals of African and European ancestry revealed three independently associated variants in the IFIH1 gene: an intronic variant, rs13023380 [Pmeta = 5.20×10−14; odds ratio, 95% confidence interval = 0.82 (0.78–0.87)], and two missense variants, rs1990760 (Ala946Thr) [Pmeta = 3.08×10−7; 0.88 (0.84–0.93)] and rs10930046 (Arg460His) [Pdom = 1.16×10−8; 0.70 (0.62–0.79)]. Both missense variants produced dramatic phenotypic changes in apoptosis and inflammation-related gene expression. We experimentally validated function of the intronic SNP by DNA electrophoresis, protein identification, and in vitro protein binding assays. DNA carrying the intronic risk allele rs13023380 showed reduced binding efficiency to a cellular protein complex including nucleolin and lupus autoantigen Ku70/80, and showed reduced transcriptional activity in vivo. Thus, in SLE patients, genetic susceptibility could create a biochemical imbalance that dysregulates nucleolin, Ku70/80, or other nucleic acid regulatory proteins. This could promote antibody hypermutation and auto-antibody generation, further destabilizing the cellular network. Together with molecular modeling, our results establish a distinct role for IFIH1 in apoptosis, inflammation, and autoantibody production, and explain the molecular basis of these three risk alleles for SLE pathogenesis. PMID

  16. Admixture mapping in lupus identifies multiple functional variants within IFIH1 associated with apoptosis, inflammation, and autoantibody production.

    Directory of Open Access Journals (Sweden)

    Julio E Molineros

    Full Text Available Systemic lupus erythematosus (SLE is an inflammatory autoimmune disease with a strong genetic component. African-Americans (AA are at increased risk of SLE, but the genetic basis of this risk is largely unknown. To identify causal variants in SLE loci in AA, we performed admixture mapping followed by fine mapping in AA and European-Americans (EA. Through genome-wide admixture mapping in AA, we identified a strong SLE susceptibility locus at 2q22-24 (LOD=6.28, and the admixture signal is associated with the European ancestry (ancestry risk ratio ~1.5. Large-scale genotypic analysis on 19,726 individuals of African and European ancestry revealed three independently associated variants in the IFIH1 gene: an intronic variant, rs13023380 [P(meta = 5.20×10(-14; odds ratio, 95% confidence interval = 0.82 (0.78-0.87], and two missense variants, rs1990760 (Ala946Thr [P(meta = 3.08×10(-7; 0.88 (0.84-0.93] and rs10930046 (Arg460His [P(dom = 1.16×10(-8; 0.70 (0.62-0.79]. Both missense variants produced dramatic phenotypic changes in apoptosis and inflammation-related gene expression. We experimentally validated function of the intronic SNP by DNA electrophoresis, protein identification, and in vitro protein binding assays. DNA carrying the intronic risk allele rs13023380 showed reduced binding efficiency to a cellular protein complex including nucleolin and lupus autoantigen Ku70/80, and showed reduced transcriptional activity in vivo. Thus, in SLE patients, genetic susceptibility could create a biochemical imbalance that dysregulates nucleolin, Ku70/80, or other nucleic acid regulatory proteins. This could promote antibody hypermutation and auto-antibody generation, further destabilizing the cellular network. Together with molecular modeling, our results establish a distinct role for IFIH1 in apoptosis, inflammation, and autoantibody production, and explain the molecular basis of these three risk alleles for SLE pathogenesis.

  17. Admixture analysis of stocked brown trout populations using mapped microsatellite DNA markers: indigenous trout persist in introgressed populations

    OpenAIRE

    Hansen, Michael M; Mensberg, Karen-Lise D.

    2009-01-01

    Admixture between wild and captive populations is an increasing concern in conservation biology. Understanding the extent of admixture and the processes involved requires identification of admixed and non-admixed individuals. This can be achieved by statistical methods employing Bayesian clustering, but resolution is low if genetic differentiation is weak. Here, we analyse stocked brown trout populations represented by historical (1943–1956) and contemporary (2000s) samples, where genetic dif...

  18. Structural Modeling Using "Scanning and Mapping" Technique

    Science.gov (United States)

    Amos, Courtney L.; Dash, Gerald S.; Shen, J. Y.; Ferguson, Frederick; Noga, Donald F. (Technical Monitor)

    2000-01-01

    Supported by NASA Glenn Center, we are in the process developing a structural damage diagnostic and monitoring system for rocket engines, which consists of five modules: Structural Modeling, Measurement Data Pre-Processor, Structural System Identification, Damage Detection Criterion, and Computer Visualization. The function of the system is to detect damage as it is incurred by the engine structures. The scientific principle to identify damage is to utilize the changes in the vibrational properties between the pre-damaged and post-damaged structures. The vibrational properties of the pre-damaged structure can be obtained based on an analytic computer model of the structure. Thus, as the first stage of the whole research plan, we currently focus on the first module - Structural Modeling. Three computer software packages are selected, and will be integrated for this purpose. They are PhotoModeler-Pro, AutoCAD-R14, and MSC/NASTRAN. AutoCAD is the most popular PC-CAD system currently available in the market. For our purpose, it plays like an interface to generate structural models of any particular engine parts or assembly, which is then passed to MSC/NASTRAN for extracting structural dynamic properties. Although AutoCAD is a powerful structural modeling tool, the complexity of engine components requires a further improvement in structural modeling techniques. We are working on a so-called "scanning and mapping" technique, which is a relatively new technique. The basic idea is to producing a full and accurate 3D structural model by tracing on multiple overlapping photographs taken from different angles. There is no need to input point positions, angles, distances or axes. Photographs can be taken by any types of cameras with different lenses. With the integration of such a modeling technique, the capability of structural modeling will be enhanced. The prototypes of any complex structural components will be produced by PhotoModeler first based on existing similar

  19. Conductivity map from scanning tunneling potentiometry.

    Science.gov (United States)

    Zhang, Hao; Li, Xianqi; Chen, Yunmei; Durand, Corentin; Li, An-Ping; Zhang, X-G

    2016-08-01

    We present a novel method for extracting two-dimensional (2D) conductivity profiles from large electrochemical potential datasets acquired by scanning tunneling potentiometry of a 2D conductor. The method consists of a data preprocessing procedure to reduce/eliminate noise and a numerical conductivity reconstruction. The preprocessing procedure employs an inverse consistent image registration method to align the forward and backward scans of the same line for each image line followed by a total variation (TV) based image restoration method to obtain a (nearly) noise-free potential from the aligned scans. The preprocessed potential is then used for numerical conductivity reconstruction, based on a TV model solved by accelerated alternating direction method of multiplier. The method is demonstrated on a measurement of the grain boundary of a monolayer graphene, yielding a nearly 10:1 ratio for the grain boundary resistivity over bulk resistivity.

  20. Conductivity map from scanning tunneling potentiometry

    Science.gov (United States)

    Zhang, Hao; Li, Xianqi; Chen, Yunmei; Durand, Corentin; Li, An-Ping; Zhang, X.-G.

    2016-08-01

    We present a novel method for extracting two-dimensional (2D) conductivity profiles from large electrochemical potential datasets acquired by scanning tunneling potentiometry of a 2D conductor. The method consists of a data preprocessing procedure to reduce/eliminate noise and a numerical conductivity reconstruction. The preprocessing procedure employs an inverse consistent image registration method to align the forward and backward scans of the same line for each image line followed by a total variation (TV) based image restoration method to obtain a (nearly) noise-free potential from the aligned scans. The preprocessed potential is then used for numerical conductivity reconstruction, based on a TV model solved by accelerated alternating direction method of multiplier. The method is demonstrated on a measurement of the grain boundary of a monolayer graphene, yielding a nearly 10:1 ratio for the grain boundary resistivity over bulk resistivity.

  1. Orientation mapping of semicrystalline polymers using scanning electron nanobeam diffraction.

    Science.gov (United States)

    Panova, Ouliana; Chen, X Chelsea; Bustillo, Karen C; Ophus, Colin; Bhatt, Mahesh P; Balsara, Nitash; Minor, Andrew M

    2016-09-01

    We demonstrate a scanning electron nanobeam diffraction technique that can be used for mapping the size and distribution of nanoscale crystalline regions in a polymer blend. In addition, it can map the relative orientation of crystallites and the degree of crystallinity of the material. The model polymer blend is a 50:50w/w mixture of semicrystalline poly(3-hexylthiophene-2,5-diyl) (P3HT) and amorphous polystyrene (PS). The technique uses a scanning electron beam to raster across the sample and acquires a diffraction image at each probe position. Through image alignment and filtering, the diffraction image dataset enables mapping of the crystalline regions within the scanned area and construction of an orientation map. PMID:27323282

  2. A genome-wide admixture scan identifies MYH9 as a candidate locus associated with non-diabetic end stage renal disease in African Americans

    Science.gov (United States)

    Linda Kao, WH; Klag, Michael J; Meoni, Lucy A; Reich, David; Berthier-Schaad, Yvette; Li, Man; Coresh, Josef; Patterson, Nick; Tandon, Arti; Powe, Neil R; Fink, Nancy E; Sadler, John H; Weir, Matthew R; Abboud, Hanna E; Adler, Sharon; Divers, Jasmin; Iyengar, Sudha K; Freedman, Barry I; Kimmel, Paul L; Knowler, William C; Kohn, Orly F; Kramp, Kristopher; Leehey, David J; Nicholas, Susanne; Pahl, Madeleine; Schelling, Jeffrey R; Sedor, John R; Thornley-Brown, Denyse; Winkler, Cheryl A; Smith, Michael W.; Parekh, Rulan S.

    2008-01-01

    End stage renal disease (ESRD) has a four times higher incidence in African Americans compared to European Americans. This led to the hypothesis that susceptibility alleles for ESRD have a higher frequency in West African than European gene pool. We performed a genome-wide admixture scan in 1,372 ESRD cases and 806 controls and demonstrated a highly significant association between excess African ancestry and non-diabetic ESRD (LOD 5.70) but not diabetic ESRD (LOD 0.47) on chromosome 22q12. Each copy of the European ancestral allele conferred a relative risk of 0.50 (95% credible interval 0.39 – 0.63) compared to African ancestry. Multiple common SNPs (allele frequency ranging from 0.2 to 0.6) in the gene that encodes non-muscle myosin heavy chain type II isoform A (MYH9) were associated with 2-4 times greater risk of non-diabetic ESRD and accounted for a large proportion of the excess risk of ESRD observed in African compared to European Americans. PMID:18794854

  3. Temperature mapping of operating nanoscale devices by scanning probe thermometry

    Science.gov (United States)

    Menges, Fabian; Mensch, Philipp; Schmid, Heinz; Riel, Heike; Stemmer, Andreas; Gotsmann, Bernd

    2016-03-01

    Imaging temperature fields at the nanoscale is a central challenge in various areas of science and technology. Nanoscopic hotspots, such as those observed in integrated circuits or plasmonic nanostructures, can be used to modify the local properties of matter, govern physical processes, activate chemical reactions and trigger biological mechanisms in living organisms. The development of high-resolution thermometry techniques is essential for understanding local thermal non-equilibrium processes during the operation of numerous nanoscale devices. Here we present a technique to map temperature fields using a scanning thermal microscope. Our method permits the elimination of tip-sample contact-related artefacts, a major hurdle that so far has limited the use of scanning probe microscopy for nanoscale thermometry. We map local Peltier effects at the metal-semiconductor contacts to an indium arsenide nanowire and self-heating of a metal interconnect with 7 mK and sub-10 nm spatial temperature resolution.

  4. Applications of orientation mapping by scanning and transmission electron microscopy

    DEFF Research Database (Denmark)

    Juul Jensen, D.

    1997-01-01

    The potentials of orientation mapping techniques (in the following referred to as OIM) for studies of thermomechanical processes are analysed. Both transmission electron microscopy (TEM) and scanning electron microscopy (SEM) based OIM techniques are considered. Among the thermomechanical processes......, focus is on cold deformation and recrystallization processes. It is described how the OIM techniques may be applied for studies of such processes. Results of OIM measurements supplement more traditional TEM and SEM microstructure characterizations as well as bulk texture measurements, and new...

  5. High-Resolution Underwater Mapping Using Side-Scan Sonar.

    Directory of Open Access Journals (Sweden)

    Antoni Burguera

    Full Text Available The goal of this study is to generate high-resolution sea floor maps using a Side-Scan Sonar(SSS. This is achieved by explicitly taking into account the SSS operation as follows. First, the raw sensor data is corrected by means of a physics-based SSS model. Second, the data is projected to the sea-floor. The errors involved in this projection are thoroughfully analysed. Third, a probabilistic SSS model is defined and used to estimate the probability of each sea-floor region to be observed. This probabilistic information is then used to weight the contribution of each SSS measurement to the map. Because of these models, arbitrary map resolutions can be achieved, even beyond the sensor resolution. Finally, a geometric map building method is presented and combined with the probabilistic approach. The resulting map is composed of two layers. The echo intensity layer holds the most likely echo intensities at each point in the sea-floor. The probabilistic layer contains information about how confident can the user or the higher control layers be about the echo intensity layer data. Experimental results have been conducted in a large subsea region.

  6. High-Resolution Underwater Mapping Using Side-Scan Sonar.

    Science.gov (United States)

    Burguera, Antoni; Oliver, Gabriel

    2016-01-01

    The goal of this study is to generate high-resolution sea floor maps using a Side-Scan Sonar(SSS). This is achieved by explicitly taking into account the SSS operation as follows. First, the raw sensor data is corrected by means of a physics-based SSS model. Second, the data is projected to the sea-floor. The errors involved in this projection are thoroughfully analysed. Third, a probabilistic SSS model is defined and used to estimate the probability of each sea-floor region to be observed. This probabilistic information is then used to weight the contribution of each SSS measurement to the map. Because of these models, arbitrary map resolutions can be achieved, even beyond the sensor resolution. Finally, a geometric map building method is presented and combined with the probabilistic approach. The resulting map is composed of two layers. The echo intensity layer holds the most likely echo intensities at each point in the sea-floor. The probabilistic layer contains information about how confident can the user or the higher control layers be about the echo intensity layer data. Experimental results have been conducted in a large subsea region.

  7. Continuous capacitance-voltage spectroscopy mapping for scanning microwave microscopy.

    Science.gov (United States)

    Moertelmaier, M; Huber, H P; Rankl, C; Kienberger, F

    2014-01-01

    A new method, scanning sawtooth capacitance spectroscopy (SSCS), is proposed to measure a map of capacitance/voltage curves (C-V) by applying a low frequency voltage sawtooth signal (20-100 Hz) to the AFM tip while scanning. For this a scanning microwave microscope (SMM) is used to acquire calibrated capacitance data in the high frequency range of 1-20 GHz. While the capacitance is acquired pixel by pixel, the applied voltage signal is recorded as well, and each pixel of the capacitance is assigned the corresponding voltage value. Assuming the voltage variable is smooth over time, adjacent pixels within a scan line will have similar voltage values and a small sequence of neighboring pixels can be combined into a virtual C-V spectroscopy curve. With standard SMM operation parameters roughly 26,000 C-V curves can be acquired within few minutes data acquisition time. The method is demonstrated for n-type and p-type silicon semiconductor samples and can be applied to other samples including new materials and bio-membranes. PMID:24012937

  8. Multispectral Airborne Laser Scanning for Automated Map Updating

    Science.gov (United States)

    Matikainen, Leena; Hyyppä, Juha; Litkey, Paula

    2016-06-01

    During the last 20 years, airborne laser scanning (ALS), often combined with multispectral information from aerial images, has shown its high feasibility for automated mapping processes. Recently, the first multispectral airborne laser scanners have been launched, and multispectral information is for the first time directly available for 3D ALS point clouds. This article discusses the potential of this new single-sensor technology in map updating, especially in automated object detection and change detection. For our study, Optech Titan multispectral ALS data over a suburban area in Finland were acquired. Results from a random forests analysis suggest that the multispectral intensity information is useful for land cover classification, also when considering ground surface objects and classes, such as roads. An out-of-bag estimate for classification error was about 3% for separating classes asphalt, gravel, rocky areas and low vegetation from each other. For buildings and trees, it was under 1%. According to feature importance analyses, multispectral features based on several channels were more useful that those based on one channel. Automatic change detection utilizing the new multispectral ALS data, an old digital surface model (DSM) and old building vectors was also demonstrated. Overall, our first analyses suggest that the new data are very promising for further increasing the automation level in mapping. The multispectral ALS technology is independent of external illumination conditions, and intensity images produced from the data do not include shadows. These are significant advantages when the development of automated classification and change detection procedures is considered.

  9. Scanned Hardcopy Maps, Walworth County Historical Airphotos scanned and georeferenced, Published in 2011, Not Applicable scale, Walworth County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Scanned Hardcopy Maps dataset, published at Not Applicable scale, was produced all or in part from Other information as of 2011. It is described as 'Walworth...

  10. Scanned Hardcopy Maps, legato data base; public works, Published in 2006, Washoe County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Scanned Hardcopy Maps dataset, was produced all or in part from Hardcopy Maps information as of 2006. It is described as 'legato data base; public works'. Data...

  11. Scanning Transmission X-Ray, Laser Scanning, and Transmission Electron Microscopy Mapping of the Exopolymeric Matrix of Microbial Biofilms

    OpenAIRE

    Lawrence, J. R.; Swerhone, G. D. W.; Leppard, G. G.; T. Araki; Zhang, X.; West, M. M.; A. P. Hitchcock

    2003-01-01

    Confocal laser scanning microscopy (CLSM), transmission electron microscopy (TEM), and soft X-ray scanning transmission X-ray microscopy (STXM) were used to map the distribution of macromolecular subcomponents (e.g., polysaccharides, proteins, lipids, and nucleic acids) of biofilm cells and matrix. The biofilms were developed from river water supplemented with methanol, and although they comprised a complex microbial community, the biofilms were dominated by heterotrophic bacteria. TEM provid...

  12. Parallel and Cached Scan Matching for Robotic 3D Mapping

    OpenAIRE

    Nuechter, Andreas

    2009-01-01

    Intelligent autonomous acting of mobile robots in unstructured environments requires 3D maps. Since manual mapping is a tedious job, automatization of this job is necessary. Automatic, consistent volumetric modeling of environments requires a solution to the simultaneous localization and map building problem (SLAM problem). In 3D task is computationally expensive, since the environments are sampled with many data points with state of the art sensing technology. In ...

  13. Sonar scan matching for simultaneous localization and mapping in confined underwater environments

    OpenAIRE

    Mallios, Angelos

    2014-01-01

    This thesis presents the development of a localization and mapping algorithm for an autonomous underwater vehicle (AUV). It is based on probabilistic scan matching of raw sonar scans within a pose-based simultaneous localization and mapping(SLAM) framework Aquesta tesis presenta el desenvolupament d’un algoritme de localització i mapeig per un vehicle submarí autònom (AUV). L’algoritme es basa en tècniques probabilístiques de scan matching utilitzant scans de sonar dins un sistema de local...

  14. Scanned Hardcopy Maps, Plat of Survey maps filed in the Manitowoc County Real Propery Lister's Office., Published in unknown, Manitowoc County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Scanned Hardcopy Maps dataset, was produced all or in part from Hardcopy Maps information as of unknown. It is described as 'Plat of Survey maps filed in the...

  15. Mapping molecules in scanning far-field fluorescence nanoscopy

    Science.gov (United States)

    Ta, Haisen; Keller, Jan; Haltmeier, Markus; Saka, Sinem K.; Schmied, Jürgen; Opazo, Felipe; Tinnefeld, Philip; Munk, Axel; Hell, Stefan W.

    2015-08-01

    In fluorescence microscopy, the distribution of the emitting molecule number in space is usually obtained by dividing the measured fluorescence by that of a single emitter. However, the brightness of individual emitters may vary strongly in the sample or be inaccessible. Moreover, with increasing (super-) resolution, fewer molecules are found per pixel, making this approach unreliable. Here we map the distribution of molecules by exploiting the fact that a single molecule emits only a single photon at a time. Thus, by analysing the simultaneous arrival of multiple photons during confocal imaging, we can establish the number and local brightness of typically up to 20 molecules per confocal (diffraction sized) recording volume. Subsequent recording by stimulated emission depletion microscopy provides the distribution of the number of molecules with subdiffraction resolution. The method is applied to mapping the three-dimensional nanoscale organization of internalized transferrin receptors on human HEK293 cells.

  16. High-Performance Grouting Mortar Based on Mineral Admixtures

    OpenAIRE

    2015-01-01

    A study on high-performance grouting mortar is reported. The common mortar was modified by mineral admixtures such as gypsum, bauxite, and alunite. The effects of mineral admixtures on the fluidity, setting time, expansion, strength, and other properties of mortar were evaluated experimentally. The microstructure of the modified mortar was characterized by X-ray diffraction, scanning electron microscopy, and mercury intrusion porosimetry. Moreover, the expansive performance and strength of th...

  17. Principal components analysis of population admixture.

    Directory of Open Access Journals (Sweden)

    Jianzhong Ma

    Full Text Available With the availability of high-density genotype information, principal components analysis (PCA is now routinely used to detect and quantify the genetic structure of populations in both population genetics and genetic epidemiology. An important issue is how to make appropriate and correct inferences about population relationships from the results of PCA, especially when admixed individuals are included in the analysis. We extend our recently developed theoretical formulation of PCA to allow for admixed populations. Because the sampled individuals are treated as features, our generalized formulation of PCA directly relates the pattern of the scatter plot of the top eigenvectors to the admixture proportions and parameters reflecting the population relationships, and thus can provide valuable guidance on how to properly interpret the results of PCA in practice. Using our formulation, we theoretically justify the diagnostic of two-way admixture. More importantly, our theoretical investigations based on the proposed formulation yield a diagnostic of multi-way admixture. For instance, we found that admixed individuals with three parental populations are distributed inside the triangle formed by their parental populations and divide the triangle into three smaller triangles whose areas have the same proportions in the big triangle as the corresponding admixture proportions. We tested and illustrated these findings using simulated data and data from HapMap III and the Human Genome Diversity Project.

  18. Dating the age of admixture via wavelet transform analysis of genome-wide data.

    Science.gov (United States)

    Pugach, Irina; Matveyev, Rostislav; Wollstein, Andreas; Kayser, Manfred; Stoneking, Mark

    2011-01-01

    We describe a PCA-based genome scan approach to analyze genome-wide admixture structure, and introduce wavelet transform analysis as a method for estimating the time of admixture. We test the wavelet transform method with simulations and apply it to genome-wide SNP data from eight admixed human populations. The wavelet transform method offers better resolution than existing methods for dating admixture, and can be applied to either SNP or sequence data from humans or other species. PMID:21352535

  19. Dating the age of admixture via wavelet transform analysis of genome-wide data

    OpenAIRE

    Pugach, Irina; Matveyev, Rostislav; Wollstein, Andreas; Kayser, Manfred; Stoneking, Mark

    2011-01-01

    textabstractWe describe a PCA-based genome scan approach to analyze genome-wide admixture structure, and introduce wavelet transform analysis as a method for estimating the time of admixture. We test the wavelet transform method with simulations and apply it to genome-wide SNP data from eight admixed human populations. The wavelet transform method offers better resolution than existing methods for dating admixture, and can be applied to either SNP or sequence data from humans or other species.

  20. Scanned Hardcopy Maps, Flood Insurance Rate Maps, countywide, Published in 2008, 1:2400 (1in=200ft) scale, Dickinson County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Scanned Hardcopy Maps dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Hardcopy Maps information as of 2008. It is described as...

  1. Scanned Hardcopy Maps, All Engineering hanging files: sewer, water, construction plans, and subdivisions, Published in 2008, City of Hutchinson.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Scanned Hardcopy Maps dataset, was produced all or in part from Hardcopy Maps information as of 2008. It is described as 'All Engineering hanging files: sewer,...

  2. Full-information Maximum Likelihood Estimation of Brand Positioning Maps Using Supermarkt Scanning Data

    NARCIS (Netherlands)

    E. Waarts (Eric); M.A. Carree (Martin); B. Wierenga (Berend)

    1991-01-01

    textabstractThe authors build on the idea put forward by Shugan to infer product maps from scanning data. They demonstrate that the actual estimation procedure used by Shugan has several methodological problems and may yield unstable estimates. They propose an alternative estimation procedure, full-

  3. Dating the age of admixture via wavelet transform analysis of genome-wide data

    NARCIS (Netherlands)

    I. Pugach (Irina); R. Matveyev (Rostislav); A. Wollstein (Andreas); M.H. Kayser (Manfred); M. Stoneking (Mark)

    2011-01-01

    textabstractWe describe a PCA-based genome scan approach to analyze genome-wide admixture structure, and introduce wavelet transform analysis as a method for estimating the time of admixture. We test the wavelet transform method with simulations and apply it to genome-wide SNP data from eight admixe

  4. Geographic patterns of genome admixture in Latin American Mestizos.

    Directory of Open Access Journals (Sweden)

    Sijia Wang

    2008-03-01

    Full Text Available The large and diverse population of Latin America is potentially a powerful resource for elucidating the genetic basis of complex traits through admixture mapping. However, no genome-wide characterization of admixture across Latin America has yet been attempted. Here, we report an analysis of admixture in thirteen Mestizo populations (i.e. in regions of mainly European and Native settlement from seven countries in Latin America based on data for 678 autosomal and 29 X-chromosome microsatellites. We found extensive variation in Native American and European ancestry (and generally low levels of African ancestry among populations and individuals, and evidence that admixture across Latin America has often involved predominantly European men and both Native and African women. An admixture analysis allowing for Native American population subdivision revealed a differentiation of the Native American ancestry amongst Mestizos. This observation is consistent with the genetic structure of pre-Columbian populations and with admixture having involved Natives from the area where the Mestizo examined are located. Our findings agree with available information on the demographic history of Latin America and have a number of implications for the design of association studies in population from the region.

  5. Geographic Patterns of Genome Admixture in Latin American Mestizos

    Science.gov (United States)

    Wang, Sijia; Ray, Nicolas; Rojas, Winston; Parra, Maria V.; Bedoya, Gabriel; Gallo, Carla; Poletti, Giovanni; Hill, Kim; Hurtado, Ana M.; Camrena, Beatriz; Nicolini, Humberto; Klitz, William; Barrantes, Ramiro; Molina, Julio A.; Freimer, Nelson B.; Bortolini, Maria Cátira; Salzano, Francisco M.; Petzl-Erler, Maria L.; Tsuneto, Luiza T.; Dipierri, José E.; Alfaro, Emma L.; Bailliet, Graciela; Bianchi, Nestor O.; Llop, Elena; Rothhammer, Francisco; Excoffier, Laurent; Ruiz-Linares, Andrés

    2008-01-01

    The large and diverse population of Latin America is potentially a powerful resource for elucidating the genetic basis of complex traits through admixture mapping. However, no genome-wide characterization of admixture across Latin America has yet been attempted. Here, we report an analysis of admixture in thirteen Mestizo populations (i.e. in regions of mainly European and Native settlement) from seven countries in Latin America based on data for 678 autosomal and 29 X-chromosome microsatellites. We found extensive variation in Native American and European ancestry (and generally low levels of African ancestry) among populations and individuals, and evidence that admixture across Latin America has often involved predominantly European men and both Native and African women. An admixture analysis allowing for Native American population subdivision revealed a differentiation of the Native American ancestry amongst Mestizos. This observation is consistent with the genetic structure of pre-Columbian populations and with admixture having involved Natives from the area where the Mestizo examined are located. Our findings agree with available information on the demographic history of Latin America and have a number of implications for the design of association studies in population from the region. PMID:18369456

  6. Note: Electron energy spectroscopy mapping of surface with scanning tunneling microscope

    Science.gov (United States)

    Li, Meng; Xu, Chunkai; Zhang, Panke; Li, Zhean; Chen, Xiangjun

    2016-08-01

    We report a novel scanning probe electron energy spectrometer (SPEES) which combines a double toroidal analyzer with a scanning tunneling microscope to achieve both topography imaging and electron energy spectroscopy mapping of surface in situ. The spatial resolution of spectroscopy mapping is determined to be better than 0.7 ± 0.2 μm at a tip sample distance of 7 μm. Meanwhile, the size of the field emission electron beam spot on the surface is also measured, and is about 3.6 ± 0.8 μm in diameter. This unambiguously demonstrates that the spatial resolution of SPEES technique can be much better than the size of the incident electron beam.

  7. WIDE-AREA MAPPING OF FOREST WITH NATIONAL AIRBORNE LASER SCANNING AND FIELD INVENTORY DATASETS

    OpenAIRE

    Monnet, J.-M.; C. Ginzler; Clivaz, J.-C.

    2016-01-01

    Airborne laser scanning (ALS) remote sensing data are now available for entire countries such as Switzerland. Methods for the estimation of forest parameters from ALS have been intensively investigated in the past years. However, the implementation of a forest mapping workflow based on available data at a regional level still remains challenging. A case study was implemented in the Canton of Valais (Switzerland). The national ALS dataset and field data of the Swiss National Forest Inventory w...

  8. Mapping chemical concentration in binary thin organic films via multi-wavelength scanning absorption microscopy (MWSAM)

    Science.gov (United States)

    Berriman, Garth; Routley, Ben; Holdsworth, John; Zhou, Xiaojing; Belcher, Warwick; Dastoor, Paul

    2014-09-01

    The composition and thickness of binary thin organic films is determined by measuring the optical absorption at multiple wavelengths across the film surface and performing a component analysis fit to absorption standards for the materials. The multiple laser wavelengths are focused onto the surface using microscope objectives and raster scanned across the film surface using a piezo-electric actuator X-Y stage. All of the wavelengths are scanned simultaneously with a frequency division multiplexing system used to separate the individual wavelength response. The composition values are in good quantitative agreement with measurements obtained by scanning transmission x-ray microscopy (STXM). This new characterization technique extends quantitative compositional mapping of thin films to thickness regimes beyond that accessible by STXM.

  9. Raman and CT scan mapping of chalcogenide glass diffusion generated gradient index profiles

    Science.gov (United States)

    Lindberg, G. P.; Berg, R. H.; Deegan, J.; Benson, R.; Salvaggio, P. S.; Gross, N.; Weinstein, B. A.; Gibson, D.; Bayya, S.; Sanghera, J.; Nguyen, V.; Kotov, M.

    2016-05-01

    Metrology of a gradient index (GRIN) material is non-trivial, especially in the realm of infrared and large refractive index. Traditional methods rely on index matching fluids which are not available for indexes as high as those found in the chalcogenide glasses (2.4-3.2). By diffusing chalcogenide glasses of similar composition one can blend the properties in a continuous way. In an effort to measure this we will present data from both x-ray computed tomography scans (CT scans) and Raman mapping scans of the diffusion profiles. Proof of concept measurements on undiffused bonded sheets of chalcogenide glasses were presented previously. The profiles measured will be of axially stacked sheets of chalcogenide glasses diffused to create a linear GRIN profile and nested tubes of chalcogenide glasses diffused to create a radial parabolic GRIN profile. We will show that the x-ray absorption in the CT scan and the intensity of select Raman peaks spatially measured through the material are indicators of the concentration of the diffusion ions and correlate to the spatial change in refractive index. We will also present finite element modeling (FEM) results and compare them to post precision glass molded (PGM) elements that have undergone CT and Raman mapping.

  10. Area-Based Mapping of Defoliation of Scots Pine Stands Using Airborne Scanning LiDAR

    Directory of Open Access Journals (Sweden)

    Hannu Hyyppä

    2013-03-01

    Full Text Available The mapping of changes in the distribution of insect-caused forest damage remains an important forest monitoring application and challenge. Efficient and accurate methods are required for mapping and monitoring changes in insect defoliation to inform forest management and reporting activities. In this research, we develop and evaluate a LiDAR-driven (Light Detection And Ranging approach for mapping defoliation caused by the Common pine sawfly (Diprion pini L.. Our method requires plot-level training data and airborne scanning LiDAR data. The approach is predicated on a forest canopy mask created by detecting forest canopy cover using LiDAR. The LiDAR returns that are reflected from the canopy (that is, returns > half of maximum plot tree height are used in the prediction of the defoliation. Predictions of defoliation are made at plot-level, which enables a direct integration of the method to operational forest management planning while also providing additional value-added from inventory-focused LiDAR datasets. In addition to the method development, we evaluated the prediction accuracy and investigated the required pulse density for operational LiDAR-based mapping of defoliation. Our method proved to be suitable for the mapping of defoliated stands, resulting in an overall mapping accuracy of 84.3% and a Cohen’s kappa coefficient of 0.68.

  11. Cell culture monitoring by impedance mapping using a multielectrode scanning impedance spectroscopy system (CellMap)

    International Nuclear Information System (INIS)

    We report on the impedance mapping of in vitro cellular morphology by electrical impedance spectroscopy, using microelectrodes. A micro multielectrode system was designed, fabricated, assembled, tested and demonstrated for the monitoring of anchorage-dependent cell behavior and morphology. This system allowed continuous, label-free, quantitative monitoring and visualization of cell adhesion, spreading, proliferation and detachment due to cell cycle processes as well as cell–drug interaction, with spatio-temporal resolution. OvCa429 ovarian cancer cells were monitored in vitro over a period of 70 hours by inoculating the cell suspension directly on the multielectrode device. The phase angle of impedance was observed to develop a distinctive shape as a result of cell attachment and proliferation. The shape of the phase angle curve reverted back to the pre-attachment shape upon detachment of cells from the substrate, caused by the addition of trypsin to the cell culture medium. The impedance data of the cell culture were then successfully modeled as a multi-parametric equivalent circuit. The model incorporated both interfacial and cell-layer impedance parameters. Upon addition of trypsin, the cell-layer parameters showed a marked decline and were eventually eliminated from the multi-parametric model, confirming the correlation of the model to the electrode–cell–electrolyte system. These experiments demonstrate the applicability of the impedance mapping technique in visualizing and quantifying physiological changes in the cell layer due to cellular processes as well as the effect of external chemical stimulus on cells (cell–drug interaction)

  12. A scanning drift tube apparatus for spatio-temporal mapping of electron swarms

    CERN Document Server

    Korolov, I; Bastykova, N Kh; Donko, Z

    2016-01-01

    A "scanning" drift tube apparatus, capable of mapping of the spatio-temporal evolution of electron swarms, developing between two plane electrodes under the effect of a homogeneous electric field, is presented. The electron swarms are initiated by photoelectron pulses and the temporal distributions of the electron flux are recorded while the electrode gap length (at a fixed electric field strength) is varied. Operation of the system is tested and verified with argon gas, the measured data are used for the evaluation of the electron bulk drift velocity. The experimental results for the space-time maps of the electron swarms - presented here for the first time - also allow clear observation of deviations from hydrodynamic transport. The swarm maps are also reproduced by particle simulations.

  13. Relics of Mining Activities in West Bohemia - Mapping by Airborne Laser Scanning

    Science.gov (United States)

    Faltýnová, M.; Pavelka, K.

    2013-07-01

    The part of the Czech Republic - West Bohemia is well known for mining activities, different types of raw materials have been extracted from mines near Jáchymov, Sokolov and other sites since medieval times till today. There are original maps of some sites, as well there is effort of some geologists to find and map relics of mining activities (such as digs visible in terrain) by land survey. The quality of these available maps is unfortunately questionable - due to its age or used methods. Our aim was to find resource useful for searching for these sites, than to use field survey to confirm our findings. We used available digital terrain model (DTM) based on airborne laser scanning (ALS) technology to map relics of mining activities in West Bohemia. The Czech Office for Surveying, Mapping and Cadastre started in 2008 project for terrain mapping using the ALS method. The aim of mapping was to get authentic and detailed DTM of the Czech Republic. About 2/3 of area is currently covered by the DTM based on ALS, this year the mapping should be complete. The dataset is characterised by the density of 1-2 points/m2 and the standard deviation in altitude of model points is up to 30 cm (in forested areas). We had DTM in form of shaded surface for one third of the Czech Republic. The shaded surface enables to highlight terrain break lines, which is suitable for archaeological research. Terrain modifications caused by human activity are characterized by terrain break lines, local tops or pits, which do not fit to local geomorphology. Visual image interpretation of the dataset is in the process.

  14. Scanned Hardcopy Maps, Prince George's County Scanned ADC Index Map from GIS Intergrated Solutions, Published in 2010, 1:100000 (1in=8333ft) scale, Prince George's County Office of Information Technology and Communications.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Scanned Hardcopy Maps dataset, published at 1:100000 (1in=8333ft) scale, was produced all or in part from Orthoimagery information as of 2010. It is described...

  15. Scanned Hardcopy Maps, Prince George's County Scanned ADC Map Pages Mosaic from GIS Intergrated Solutions, Published in 2010, 1:12000 (1in=1000ft) scale, Prince George's County Office of Information Technology and Communications.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Scanned Hardcopy Maps dataset, published at 1:12000 (1in=1000ft) scale, was produced all or in part from Orthoimagery information as of 2010. It is described...

  16. Multidimensional Laser Scanning System for Underwater Mapping of Small Structures and Bottom Topography

    Science.gov (United States)

    Fuchs, E.

    2005-05-01

    A multidimensional laser scanning imaging system is under development to investigate new concepts in underwater imaging. The system is a modification of the 3D Laser Imaging & Tracking Electro-optical System (3D LITES; HBOI, patent # 5,418,608) that was developed for 3D mapping applications in biological oceanography. The new 3D-FLITES ("F" stands for added Fluorescence capability) captures both spatial and spectral data and offers extended operation capabilities. The system can capture the range to each pixel in the sensor's field of view, the relative reflectance of each pixel (similar to "conventional" images) and five channels of fluorescence emission in the scene, captured sequentially. Multidimensional data sets can be instrumental in bottom topography mapping and object identification. The 3D FLITES has the unique capability to operate in user-selectable line or raster scanning modes if mounted on a moving platform. In raster mode two perpendicular mirrors are driven, allowing the operator to capture single frames (capturing either reflectance or fluorescence data) or a stream of images in fast rate (16 frames per second). With this operational flexibility the operator can combine a "fly over" scanning mode with "look ahead", "look sideways" and "zoom" modes. The current system is limited in range and resolution; nevertheless it can serve as a test-bed to evaluate operational parameters, data acquisition and signal processing protocols that could lead to a smaller, more efficient system in the future.

  17. Scanned Hardcopy Maps, Archived Tax Maps from 1992 with 1967 aerial orthophotography, Published in 1967, 1:4800 (1in=400ft) scale, Iredell County GIS.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Scanned Hardcopy Maps dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Orthoimagery information as of 1967. It is described as...

  18. Geomorphometric analysis of cave ceiling channels mapped with 3-D terrestrial laser scanning

    Science.gov (United States)

    Gallay, Michal; Hochmuth, Zdenko; Kaňuk, Ján; Hofierka, Jaroslav

    2016-05-01

    The change of hydrological conditions during the evolution of caves in carbonate rocks often results in a complex subterranean geomorphology, which comprises specific landforms such as ceiling channels, anastomosing half tubes, or speleothems organized vertically in different levels. Studying such complex environments traditionally requires tedious mapping; however, this is being replaced with terrestrial laser scanning technology. Laser scanning overcomes the problem of reaching high ceilings, providing new options to map underground landscapes with unprecedented level of detail and accuracy. The acquired point cloud can be handled conveniently with dedicated software, but applying traditional geomorphometry to analyse the cave surface is limited. This is because geomorphometry has been focused on parameterization and analysis of surficial terrain. The theoretical and methodological concept has been based on two-dimensional (2-D) scalar fields, which are sufficient for most cases of the surficial terrain. The terrain surface is modelled with a bivariate function of altitude (elevation) and represented by a raster digital elevation model. However, the cave is a 3-D entity; therefore, a different approach is required for geomorphometric analysis. In this paper, we demonstrate the benefits of high-resolution cave mapping and 3-D modelling to better understand the palaeohydrography of the Domica cave in Slovakia. This methodological approach adopted traditional geomorphometric methods in a unique manner and also new methods used in 3-D computer graphics, which can be applied to study other 3-D geomorphological forms.

  19. Scan matching using line segment relationships for map-based localization of mobile robot

    Institute of Scientific and Technical Information of China (English)

    GE Kun-feng; CHEN Wei-dong; WANG Jing-chuan; RAN Yu-yao

    2008-01-01

    A new scan matching method for mobile robot localization is presented, which takes line segment as the feature and matches the real scans in the given reference map by relationships of the directional-defined line segments. The alignment was done by hierarchically identifying the multiple relationships and the result was re-corded in a correspondence matrix, where the best match is defined and selected for localization. It is indicated that the searching algorithm of the best match can find the ambiguities and get rid of them. This method with less computational cost works well in occluded environment, and can correct the error in pose estimation without the need for the estimation itself. The efficiency, accuracy and robustness of this method were verified by exper-iments of localization in an occluded environment and a long-distance indoor navigation.

  20. Feature-Based Laser Scan Matching and Its Application for Indoor Mapping

    Directory of Open Access Journals (Sweden)

    Jiayuan Li

    2016-08-01

    Full Text Available Scan matching, an approach to recover the relative position and orientation of two laser scans, is a very important technique for indoor positioning and indoor modeling. The iterative closest point (ICP algorithm and its variants are the most well-known techniques for such a problem. However, ICP algorithms rely highly on the initial guess of the relative transformation, which will reduce its power for practical applications. In this paper, an initial-free 2D laser scan matching method based on point and line features is proposed. We carefully design a framework for the detection of point and line feature correspondences. First, distinct feature points are detected based on an extended 1D SIFT, and line features are extracted via a modified Split-and-Merge algorithm. In this stage, we also give an effective strategy for discarding unreliable features. The point and line features are then described by a distance histogram; the pairs achieving best matching scores are accepted as potential correct correspondences. The histogram cluster technique is adapted to filter outliers and provide an accurate initial value of the rigid transformation. We also proposed a new relative pose estimation method that is robust to outliers. We use the lq-norm (0 < q < 1 metric in this approach, in contrast to classic optimization methods whose cost function is based on the l2-norm of residuals. Extensive experiments on real data demonstrate that the proposed method is almost as accurate as ICPs and is initial free. We also show that our scan matching method can be integrated into a simultaneous localization and mapping (SLAM system for indoor mapping.

  1. Mapping of Si/SiC p-n heterojunctions using scanning internal photoemission microscopy

    Science.gov (United States)

    Shingo, Masato; Liang, Jianbo; Shigekawa, Naoteru; Arai, Manabu; Shiojima, Kenji

    2016-04-01

    We demonstrated the two-dimensional characterization of p+-Si/n--SiC heterointerfaces by scanning internal photoemission microscopy (SIPM). In internal photoemission spectra, a linear relationship was found between the square root of photoyield (Y) and photon energy, and the threshold energy (qV th) was reasonably obtained to be 1.34 eV. From the SIPM results, Y and qV th maps were successfully obtained, and nanometer-deep gaps in the junction were sensitively visualized as a pattern. These results suggest that this method is a powerful tool for investigating the inhomogeneity of heterojunctions as well as their carrier transport properties.

  2. [Mapping stakeholders' preferences in prioritization criteria for horizon scanning in healthcare technologies].

    Science.gov (United States)

    Nascimento, Aline do; Vidal, Avila Teixeira; Almeida, Rosimary Terezinha de

    2016-08-01

    Filtration and prioritization are two basics steps in horizon scanning systems. This article aimed to map stakeholders' preferences in the Brazilian Unified National Health System (SUS) regarding filtration and prioritization criteria. Two filtration criteria (time horizon and innovation) and eight prioritization criteria (relevance to epidemiology, health policies, and clinical practice; potential impact on SUS budget, healthcare providers' costs, and mortality; safety; and legal, ethical, and social aspects) were selected. Multiple correspondence analysis was used to map stakeholders' preferences within and between groups. Two groups were more homogeneous and determinant for selection of prioritization criteria. Stakeholders' professional experience had more influence than institutional affiliations. The approach showed transparent criteria selection and analysis of stakeholders' individual preferences. PMID:27487444

  3. Possibilities of a Personal Laser Scanning System for Forest Mapping and Ecosystem Services

    Directory of Open Access Journals (Sweden)

    Xinlian Liang

    2014-01-01

    Full Text Available A professional-quality, personal laser scanning (PLS system for collecting tree attributes was demonstrated in this paper. The applied system, which is wearable by human operators, consists of a multi-constellation navigation system and an ultra-high-speed phase-shift laser scanner mounted on a rigid baseplate and consisting of a single sensor block. A multipass-corridor-mapping method was developed to process PLS data and a 2,000 m2 forest plot was utilized in the test. The tree stem detection accuracy was 82.6%; the root mean square error (RMSE of the estimates of tree diameter at breast height (DBH was 5.06 cm; the RMSE of the estimates of tree location was 0.38 m. The relative RMSE of the DBH estimates was 14.63%. The results showed, for the first time, the potential of the PLS system in mapping large forest plots. Further research on mapping accuracy in various forest conditions, data correction methods and multi-sensoral positioning techniques is needed. The utilization of this system in different applications, such as harvester operations, should also be explored. In addition to collecting tree-level and plot-level data for forest inventory, other possible applications of PLS for forest ecosystem services include mapping of canopy gaps, measuring leaf area index of large areas, documenting and visualizing forest routes feasible for recreation, hiking and berry and mushroom picking.

  4. Possibilities of a personal laser scanning system for forest mapping and ecosystem services.

    Science.gov (United States)

    Liang, Xinlian; Kukko, Antero; Kaartinen, Harri; Hyyppä, Juha; Yu, Xiaowei; Jaakkola, Anttoni; Wang, Yunsheng

    2014-01-10

    A professional-quality, personal laser scanning (PLS) system for collecting tree attributes was demonstrated in this paper. The applied system, which is wearable by human operators, consists of a multi-constellation navigation system and an ultra-high-speed phase-shift laser scanner mounted on a rigid baseplate and consisting of a single sensor block. A multipass-corridor-mapping method was developed to process PLS data and a 2,000 m2 forest plot was utilized in the test. The tree stem detection accuracy was 82.6%; the root mean square error (RMSE) of the estimates of tree diameter at breast height (DBH) was 5.06 cm; the RMSE of the estimates of tree location was 0.38 m. The relative RMSE of the DBH estimates was 14.63%. The results showed, for the first time, the potential of the PLS system in mapping large forest plots. Further research on mapping accuracy in various forest conditions, data correction methods and multi-sensoral positioning techniques is needed. The utilization of this system in different applications, such as harvester operations, should also be explored. In addition to collecting tree-level and plot-level data for forest inventory, other possible applications of PLS for forest ecosystem services include mapping of canopy gaps, measuring leaf area index of large areas, documenting and visualizing forest routes feasible for recreation, hiking and berry and mushroom picking.

  5. Simultaneous Nanomechanical and Electrochemical Mapping: Combining Peak Force Tapping Atomic Force Microscopy with Scanning Electrochemical Microscopy.

    Science.gov (United States)

    Knittel, Peter; Mizaikoff, Boris; Kranz, Christine

    2016-06-21

    Soft electronic devices play a crucial role in, e.g., neural implants as stimulating electrodes, transducers for biosensors, or selective drug-delivery. Because of their elasticity, they can easily adapt to their environment and prevent immunoreactions leading to an overall improved long-term performance. In addition, flexible electronic devices such as stretchable displays will be increasingly used in everyday life, e.g., for so-called electronic wearables. Atomic force microscopy (AFM) is a versatile tool to characterize these micro- and nanostructured devices in terms of their topography. Using advanced imaging techniques such as peak force tapping (PFT), nanomechanical properties including adhesion, deformation, and Young's modulus can be simultaneously mapped along with surface features. However, conventional AFM provides limited laterally resolved information on electrical or electrochemical properties such as the activity of an electrode array. In this study, we present the first combination of AFM with scanning electrochemical microscopy (SECM) in PFT mode, thereby offering spatially correlated electrochemical and nanomechanical information paired with high-resolution topographical data under force control (QNM-AFM-SECM). The versatility of this combined scanning probe approach is demonstrated by mapping topographical, electrochemical, and nanomechanical properties of gold microelectrodes and of gold electrodes patterned onto polydimethylsiloxane.

  6. LIDAR AND INS FUSION IN PERIODS OF GPS OUTAGES FOR MOBILE LASER SCANNING MAPPING SYSTEMS

    Directory of Open Access Journals (Sweden)

    I. Klein

    2012-09-01

    Full Text Available Mobile laser scanning systems are becoming an increasingly popular means to obtain 3D coverage on a large scale. To perform the mapping, the exact position of the vehicle must be known throughout the trajectory. Exact position is achieved via integration of Global Positioning Systems (GPS and Inertial Navigation Systems (INS. Yet, in urban environments, cases of complete or even partial GPS outages may occur leaving the navigation solution to rely only on the INS. The INS navigation solution degrades with time as the Inertial Measurement Unit (IMU measurements contains noise, which permeates into the navigation equations. Degradation of the position determination leads to loss of data in such segments. To circumvent such drift and its effects, we propose fusing INS with lidar data by using building edges. This detection of edges is then translated into position data, which is used as an aiding to the INS. It thereby enables the determination of the vehicle position with a satisfactory level accuracy, sufficient to perform the laser-scanning based mapping in those outage periods.

  7. Interference features in scanning gate conductance maps of quantum point contacts with disorder

    Science.gov (United States)

    Kolasiński, K.; Szafran, B.; Brun, B.; Sellier, H.

    2016-08-01

    We consider quantum point contact (QPC) defined within a disordered two-dimensional electron gas as studied by scanning gate microscopy. We evaluate the conductance maps in the Landauer approach with a wave-function picture of electron transport for samples with both low and high electron mobility at finite temperatures. We discuss the spatial distribution of the impurities in the context of the branched electron flow. We reproduce the surprising temperature stability of the experimental interference fringes far from the QPC. Next, we discuss funnel-shaped features that accompany splitting of the branches visible in previous experiments. Finally, we study elliptical interference fringes formed by an interplay of scattering by the pointlike impurities and by the scanning probe. We discuss the details of the elliptical features as functions of the tip voltage and the temperature, showing that the first interference fringe is very robust against the thermal widening of the Fermi level. We present a simple analytical model that allows for extraction of the impurity positions and the electron-gas depletion radius induced by the negatively charged tip of the atomic force microscope, and apply this model on experimental scanning gate images showing such elliptical fringes.

  8. Towards Automatic Single-Sensor Mapping by Multispectral Airborne Laser Scanning

    Science.gov (United States)

    Ahokas, E.; Hyyppä, J.; Yu, X.; Liang, X.; Matikainen, L.; Karila, K.; Litkey, P.; Kukko, A.; Jaakkola, A.; Kaartinen, H.; Holopainen, M.; Vastaranta, M.

    2016-06-01

    This paper describes the possibilities of the Optech Titan multispectral airborne laser scanner in the fields of mapping and forestry. Investigation was targeted to six land cover classes. Multispectral laser scanner data can be used to distinguish land cover classes of the ground surface, including the roads and separate road surface classes. For forest inventory using point cloud metrics and intensity features combined, total accuracy of 93.5% was achieved for classification of three main boreal tree species (pine, spruce and birch).When using intensity features - without point height metrics - a classification accuracy of 91% was achieved for these three tree species. It was also shown that deciduous trees can be further classified into more species. We propose that intensity-related features and waveform-type features are combined with point height metrics for forest attribute derivation in area-based prediction, which is an operatively applied forest inventory process in Scandinavia. It is expected that multispectral airborne laser scanning can provide highly valuable data for city and forest mapping and is a highly relevant data asset for national and local mapping agencies in the near future.

  9. Non-Uniform Dose Mapping Controlled by Modulated Vertical and Horizontal Scans

    International Nuclear Information System (INIS)

    Since geometries of semi-conductor devices continue to shrink, the requirement for each process becomes severer to keep uniformity of electrical parameters of the semi-conductor devices. A larger wafer also causes larger variations. Thus it has been strongly required for ion implantation process to compensate for the variations from other processes because of its good dose controllability. A newly developed mapping of intentional non-uniform dosage system, which is named 'MIND system', is implemented in SEN's single-wafer-type implanters. The MIND system controls both horizontal and vertical scan speed simultaneously. Intentional two-dimensional non-uniform profiles of sheet resistance, such as concentric and eccentric profiles, are obtained only by single-step ion implantation.

  10. Using Mobile Laser Scanning Data for Features Extraction of High Accuracy Driving Maps

    Science.gov (United States)

    Yang, Bisheng; Liu, Yuan; Liang, Fuxun; Dong, Zhen

    2016-06-01

    High Accuracy Driving Maps (HADMs) are the core component of Intelligent Drive Assistant Systems (IDAS), which can effectively reduce the traffic accidents due to human error and provide more comfortable driving experiences. Vehicle-based mobile laser scanning (MLS) systems provide an efficient solution to rapidly capture three-dimensional (3D) point clouds of road environments with high flexibility and precision. This paper proposes a novel method to extract road features (e.g., road surfaces, road boundaries, road markings, buildings, guardrails, street lamps, traffic signs, roadside-trees, power lines, vehicles and so on) for HADMs in highway environment. Quantitative evaluations show that the proposed algorithm attains an average precision and recall in terms of 90.6% and 91.2% in extracting road features. Results demonstrate the efficiencies and feasibilities of the proposed method for extraction of road features for HADMs.

  11. Scanning electrochemical mapping of spatially localized electrochemical reactions induced by surface potential gradients.

    Science.gov (United States)

    Jayaraman, Shrisudersan; May, Erin L; Hillier, Andrew C

    2006-12-01

    The influence of a surface potential gradient on the location and extent of electrochemical reactions was examined using a scanning electrochemical microscope. A linear potential gradient was imposed on the surface of a platinum-coated indium tin oxide electrode by applying two different potential values at the edges of the electrode. The applied potentials were used to control the location and extent of several electrochemical reactions, including the oxidation of Ru(NH3)6(2+), the oxidation of H2, and the oxidation of H2 in the presence of adsorbed CO. Scanning electrochemical mapping of these reactions was achieved by probing the feedback current associated with the oxidation products. The oxidation of Ru(NH3)6(2+) occurred at locations where the applied potential was positive of the formal potential of the Ru(NH3)6(2+/3+) redox couple. The position of this reaction on the surface could be spatially translated by manipulating the terminal potentials. The rate of hydrogen oxidation on the platinum-coated electrode varied spatially in the presence of a potential gradient and correlated with the nature of the electrode surface. High oxidation rates occurred at low potentials, with decreasing rates observed as the potential increased to values where platinum oxides formed. The extent of oxide formation versus position was confirmed with in-situ ellipsometry mapping. In the presence of adsorbed carbon monoxide, a potential gradient created a localized region of high activity for hydrogen oxidation at potentials between where carbon monoxide was adsorbed and platinum oxides formed. The position of this localized region of activity could be readily translated along the surface by changing the terminal potential values. The ability to manipulate electrochemical reactions spatially on a surface has potential application in microscale analytical devices as well as in the discovery and analysis of electrocatalytic systems. PMID:17128999

  12. Ancient Admixture in Human History

    Science.gov (United States)

    Patterson, Nick; Moorjani, Priya; Luo, Yontao; Mallick, Swapan; Rohland, Nadin; Zhan, Yiping; Genschoreck, Teri; Webster, Teresa; Reich, David

    2012-01-01

    Population mixture is an important process in biology. We present a suite of methods for learning about population mixtures, implemented in a software package called ADMIXTOOLS, that support formal tests for whether mixture occurred and make it possible to infer proportions and dates of mixture. We also describe the development of a new single nucleotide polymorphism (SNP) array consisting of 629,433 sites with clearly documented ascertainment that was specifically designed for population genetic analyses and that we genotyped in 934 individuals from 53 diverse populations. To illustrate the methods, we give a number of examples that provide new insights about the history of human admixture. The most striking finding is a clear signal of admixture into northern Europe, with one ancestral population related to present-day Basques and Sardinians and the other related to present-day populations of northeast Asia and the Americas. This likely reflects a history of admixture between Neolithic migrants and the indigenous Mesolithic population of Europe, consistent with recent analyses of ancient bones from Sweden and the sequencing of the genome of the Tyrolean “Iceman.” PMID:22960212

  13. Volumetric evolution of Surtsey, Iceland, from topographic maps and scanning airborne laser altimetry

    Science.gov (United States)

    Garvin, J.B.; Williams, R.S.; Frawley, J.J.; Krabill, W.B.

    2000-01-01

    The volumetric evolution of Surtsey has been estimated on the basis of digital elevation models derived from NASA scanning airborne laser altimeter surveys (20 July 1998), as well as digitized 1:5,000-scale topographic maps produced by the National Land Survey of Iceland and by Norrman. Subaerial volumes have been computed from co-registered digital elevation models (DEM's) from 6 July 1968, 11 July 1975, 16 July 1993, and 20 July 1998 (scanning airborne laser altimetry), as well as true surface area (above mean sea level). Our analysis suggests that the subaerial volume of Surtsey has been reduced from nearly 0.100 km3 on 6 July 1968 to 0.075 km3 on 20 July 1998. Linear regression analysis of the temporal evolution of Surtsey's subaerial volume indicates that most of its subaerial surface will be at or below mean sea-level by approximately 2100. This assumes a conservative estimate of continuation of the current pace of marine erosion and mass-wasting on the island, including the indurated core of the conduits of the Surtur I and Surtur II eruptive vents. If the conduits are relatively resistant to marine erosion they will become sea stacks after the rest of the island has become a submarine shoal, and some portions of the island could survive for centuries. The 20 July 1998 scanning laser altimeter surveys further indicate rapid enlargement of erosional canyons in the northeastern portion of the partial tephra ring associated with Surtur I. Continued airborne and eventually spaceborne topographic surveys of Surtsey are planned to refine the inter-annual change of its subaerial volume.

  14. Mapping Carrier Dynamics on Material Surfaces in Space and Time using Scanning Ultrafast Electron Microscopy.

    Science.gov (United States)

    Sun, Jingya; Adhikari, Aniruddha; Shaheen, Basamat S; Yang, Haoze; Mohammed, Omar F

    2016-03-17

    Selectively capturing the ultrafast dynamics of charge carriers on materials surfaces and at interfaces is crucial to the design of solar cells and optoelectronic devices. Despite extensive research efforts over the past few decades, information and understanding about surface-dynamical processes, including carrier trapping and recombination remains extremely limited. A key challenge is to selectively map such dynamic processes, a capability that is hitherto impractical by time-resolved laser techniques, which are limited by the laser's relatively large penetration depth and consequently these techniques record mainly bulk information. Such surface dynamics can only be mapped in real space and time by applying four-dimensional (4D) scanning ultrafast electron microscopy (S-UEM), which records snapshots of materials surfaces with nanometer spatial and subpicosecond temporal resolutions. In this method, the secondary electron (SE) signal emitted from the sample's surface is extremely sensitive to the surface dynamics and is detected in real time. In several unique applications, we spatially and temporally visualize the SE energy gain and loss, the charge carrier dynamics on the surface of InGaN nanowires and CdSe single crystal and its powder film. We also discuss the mechanisms for the observed dynamics, which will be the foundation for future potential applications of S-UEM to a wide range of studies on material surfaces and device interfaces.

  15. Mapping Carrier Dynamics on Material Surfaces in Space and Time using Scanning Ultrafast Electron Microscopy

    KAUST Repository

    Sun, Jingya

    2016-02-25

    Selectively capturing the ultrafast dynamics of charge carriers on materials surfaces and at interfaces is crucial to the design of solar cells and optoelectronic devices. Despite extensive research efforts over the past few decades, information and understanding about surface-dynamical processes, including carrier trapping and recombination remains extremely limited. A key challenge is to selectively map such dynamic processes, a capability that is hitherto impractical by time-resolved laser techniques, which are limited by the laser’s relatively large penetration depth and consequently they record mainly bulk information. Such surface dynamics can only be mapped in real space and time by applying four-dimensional (4D) scanning ultrafast electron microscopy (S-UEM), which records snapshots of materials surfaces with nanometer spatial and sub-picosecond temporal resolutions. In this method, the secondary electron (SE) signal emitted from the sample’s surface is extremely sensitive to the surface dynamics and is detected in real time. In several unique applications, we spatially and temporally visualize the SE energy gain and loss, the charge carrier dynamics on the surface of InGaN nanowires and CdSe single crystals and its powder film. We also provide the mechanisms for the observed dynamics, which will be the foundation for future potential applications of S-UEM to a wide range of studies on material surfaces and device interfaces.

  16. Wide-Area Mapping of Forest with National Airborne Laser Scanning and Field Inventory Datasets

    Science.gov (United States)

    Monnet, J.-M.; Ginzler, C.; Clivaz, J.-C.

    2016-06-01

    Airborne laser scanning (ALS) remote sensing data are now available for entire countries such as Switzerland. Methods for the estimation of forest parameters from ALS have been intensively investigated in the past years. However, the implementation of a forest mapping workflow based on available data at a regional level still remains challenging. A case study was implemented in the Canton of Valais (Switzerland). The national ALS dataset and field data of the Swiss National Forest Inventory were used to calibrate estimation models for mean and maximum height, basal area, stem density, mean diameter and stem volume. When stratification was performed based on ALS acquisition settings and geographical criteria, satisfactory prediction models were obtained for volume (R2 = 0.61 with a root mean square error of 47 %) and basal area (respectively 0.51 and 45 %) while height variables had an error lower than 19%. This case study shows that the use of nationwide ALS and field datasets for forest resources mapping is cost efficient, but additional investigations are required to handle the limitations of the input data and optimize the accuracy.

  17. Nanoscale structural and functional mapping of nacre by scanning probe microscopy techniques.

    Science.gov (United States)

    Zhou, Xilong; Miao, Hongchen; Li, Faxin

    2013-12-01

    Nacre has received great attention due to its nanoscale hierarchical structure and extraordinary mechanical properties. Meanwhile, the nanoscale piezoelectric properties of nacre have also been investigated but the structure-function relationship has never been addressed. In this work, firstly we realized quantitative nanomechanical mapping of nacre of a green abalone using atomic force acoustic microscopy (AFAM). The modulus of the mineral tablets is determined to be ~80 GPa and that of the organic biopolymer no more than 23 GPa, and the organic-inorganic interface width is determined to be about 34 ± 9 nm. Then, we conducted both AFAM and piezoresponse force microscopy (PFM) mapping in the same scanning area to explore the correlations between the nanomechanical and piezoelectric properties. The PFM testing shows that the organic biopolymer exhibits a significantly stronger piezoresponse than the mineral tablets, and they permeate each other, which is very difficult to reproduce in artificial materials. Finally, the phase hysteresis loops and amplitude butterfly loops were also observed using switching spectroscopy PFM, implying that nacre may also be a bio-ferroelectric material. The obtained nanoscale structural and functional properties of nacre could be very helpful in understanding its deformation mechanism and designing biomimetic materials of extraordinary properties.

  18. Simultaneous Interfacial Reactivity and Topography Mapping with Scanning Ion Conductance Microscopy.

    Science.gov (United States)

    Momotenko, Dmitry; McKelvey, Kim; Kang, Minkyung; Meloni, Gabriel N; Unwin, Patrick R

    2016-03-01

    Scanning ion conductance microscopy (SICM) is a powerful technique for imaging the topography of a wide range of materials and interfaces. In this report, we develop the use and scope of SICM, showing how it can be used for mapping spatial distributions of ionic fluxes due to (electro)chemical reactions occurring at interfaces. The basic idea is that there is a change of ion conductance inside a nanopipet probe when it approaches an active site, where the ionic composition is different to that in bulk solution, and this can be sensed via the current flow in the nanopipet with an applied bias. Careful tuning of the tip potential allows the current response to be sensitive to either topography or activity, if desired. Furthermore, the use of a distance modulation SICM scheme allows reasonably faithful probe positioning using the resulting ac response, irrespective of whether there is a reaction at the interface that changes the local ionic composition. Both strategies (distance modulation or tuned bias) allow simultaneous topography-activity mapping with a single channel probe. The application of SICM reaction imaging is demonstrated on several examples, including voltammetric mapping of electrocatalytic reactions on electrodes and high-speed electrochemical imaging at rates approaching 4 s per image frame. These two distinct approaches provide movies of electrochemical current as a function of potential with hundreds of frames (images) of surface reactivity, to reveal a wealth of spatially resolved information on potential- (and time) dependent electrochemical phenomena. The experimental studies are supported by detailed finite element method modeling that places the technique on a quantitative footing.

  19. Semi-automatic mapping of cultural heritage from airborne laser scanning using deep learning

    Science.gov (United States)

    Due Trier, Øivind; Salberg, Arnt-Børre; Holger Pilø, Lars; Tonning, Christer; Marius Johansen, Hans; Aarsten, Dagrun

    2016-04-01

    This paper proposes to use deep learning to improve semi-automatic mapping of cultural heritage from airborne laser scanning (ALS) data. Automatic detection methods, based on traditional pattern recognition, have been applied in a number of cultural heritage mapping projects in Norway for the past five years. Automatic detection of pits and heaps have been combined with visual interpretation of the ALS data for the mapping of deer hunting systems, iron production sites, grave mounds and charcoal kilns. However, the performance of the automatic detection methods varies substantially between ALS datasets. For the mapping of deer hunting systems on flat gravel and sand sediment deposits, the automatic detection results were almost perfect. However, some false detections appeared in the terrain outside of the sediment deposits. These could be explained by other pit-like landscape features, like parts of river courses, spaces between boulders, and modern terrain modifications. However, these were easy to spot during visual interpretation, and the number of missed individual pitfall traps was still low. For the mapping of grave mounds, the automatic method produced a large number of false detections, reducing the usefulness of the semi-automatic approach. The mound structure is a very common natural terrain feature, and the grave mounds are less distinct in shape than the pitfall traps. Still, applying automatic mound detection on an entire municipality did lead to a new discovery of an Iron Age grave field with more than 15 individual mounds. Automatic mound detection also proved to be useful for a detailed re-mapping of Norway's largest Iron Age grave yard, which contains almost 1000 individual graves. Combined pit and mound detection has been applied to the mapping of more than 1000 charcoal kilns that were used by an iron work 350-200 years ago. The majority of charcoal kilns were indirectly detected as either pits on the circumference, a central mound, or both

  20. Role of organic admixtures on thaumasite precipitation

    OpenAIRE

    Blanco-Varela, María Teresa; Carmona-Quiroga, Paula María; Sáez del Bosque, I. F.; Martínez-Ramírez, S.

    2012-01-01

    Thaumasite formation is normally a slow process; however some studies have shown that the presence of sucrose promotes its formation substantially. Many of today's concretes contain organic admixtures and no research has been conducted to date to determine whether the presence of these admixtures may induce or favour thaumasite formation. The present study aimed to ascertain whether, like sucrose, admixtures may further that process, and to propose a working methodology to do so. ...

  1. Composition mapping in InGaN by scanning transmission electron microscopy

    International Nuclear Information System (INIS)

    We suggest a method for chemical mapping that is based on scanning transmission electron microscopy (STEM) imaging with a high-angle annular dark field (HAADF) detector. The analysis method uses a comparison of intensity normalized with respect to the incident electron beam with intensity calculated employing the frozen lattice approximation. This procedure is validated with an In0.07Ga0.93N layer with homogeneous In concentration, where the STEM results were compared with energy filtered imaging, strain state analysis and energy dispersive X-ray analysis. Good agreement was obtained, if the frozen lattice simulations took into account static atomic displacements, caused by the different covalent radii of In and Ga atoms. Using a sample with higher In concentration and series of 32 images taken within 42 min scan time, we did not find any indication for formation of In rich regions due to electron beam irradiation, which is reported in literature to occur for the parallel illumination mode. Image simulation of an In0.15Ga0.85N layer that was elastically relaxed with empirical Stillinger-Weber potentials did not reveal significant impact of lattice plane bending on STEM images as well as on the evaluated In concentration profiles for specimen thicknesses of 5, 15 and 50 nm. Image simulation of an abrupt interface between GaN and In0.15Ga0.85N for specimen thicknesses up to 200 nm showed that artificial blurring of interfaces is significantly smaller than expected from a simple geometrical model that is based on the beam convergence only. As an application of the method, we give evidence for the existence of In rich regions in an InGaN layer which shows signatures of quantum dot emission in microphotoluminescence spectroscopy experiments. -- Highlights: → Composition mapping in InGaN using quantitative STEM. → No electron beam induced In clustering in InGaN observed for STEM. → Small influence of lattice plane bending for STEM of InGaN/GaN. → In composition

  2. An interactive mapping tool for visualizing lacunarity of laser scanned point clouds

    Science.gov (United States)

    Kania, Adam; Székely, Balázs

    2016-04-01

    Lacunarity, a measure of the spatial distribution of the empty space in a certain model or real space over large spatial scales, is found to be a useful descriptive quantity in many fields using imagery, including, among others, geology, dentistry, neurology. Its application in ecology was suggested more than 20 years ago. The main problem of its application was the lack of appropriate high resolution data. Nowadays, full-waveform laser scanning, also known as FWF LiDAR, provides the tool for mapping the vegetation in unprecedented details and accuracy. Consequently, the lacunarity concept can be revitalized, in order to study the structure of the vegetation in this sense as well. Calculation of lacunarity, even if it is done in two dimensions (2D), is still has its problems: on one hand it is a number-crunching procedure, on the other hand, it produces 4D results: at each 3D point it returns a set of data that are function of scale. These data sets are difficult to visualize, to evaluate, and to compare. In order to solve this problem, an interactive mapping tool has been conceptualized that is designed to manipulate and visualize the data, lets the user set parameters for best visualization or comparison results. The system is able to load large amounts of data, visualize them as lacunarity curves, or map view as horizontal slices or in 3D point clouds coloured according to the user's choice. Lacunarity maps are presented as a series of (usually) horizontal profiles, e.g. rasters, which cells contain color-mapped values of selected lacunarity of the point cloud. As lacunarity is usually analysed in a series of successive windows sizes, the tool can show a series of rasters with sequentially animated lacunarity maps calculated for various window sizes. A very fast switching of colour schemes is possible to facilitate rapid visual feedback to better understand underlying data patterns exposed by lacunarity functions. In the comparison mode, two sites (or two areas

  3. Mapping Infrared Data on Terrestrial Laser Scanning 3D Models of Buildings

    Directory of Open Access Journals (Sweden)

    Mattia Previtali

    2011-08-01

    Full Text Available A new 3D acquisition and processing procedure to map RGB, thermal IR and near infrared images (NIR on a detailed 3D model of a building is presented. The combination and fusion of different data sources allows the generation of 3D thermal data useful for different purposes such as localization, visualization, and analysis of anomalies in contemporary architecture. The classic approach, which is currently used to map IR images on 3D models, is based on the direct registration of each single image by using space resection or homography. This approach is largely time consuming and in many cases suffers from poor object texture. To overcome these drawbacks, a “bi-camera” system coupling a thermal IR camera to a RGB camera has been setup. The second sensor is used to orient the “bi-camera” through a photogrammetric network also including free-handled camera stations to strengthen the block geometry. In many cases the bundle adjustment can be executed through a procedure for automatic extraction of tie points. Terrestrial laser scanning is adopted to retrieve the 3D model building. The integration of a low-cost NIR camera accumulates further radiometric information on the final 3D model. The use of such a sensor has not been exploited until now to assess the conservation state of buildings. Here some interesting findings from this kind of analysis are reported. The paper shows the methodology and its experimental application to a couple of buildings in the main Campus of Politecnico di Milano University, where IR thermography has previously been carried out for conservation and maintenance purposes.

  4. Mapping of methane from Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY)

    Science.gov (United States)

    Tan, K. C.; Lim, H. S.; MatJafri, M. Z.

    2012-11-01

    Among all the greenhouse gases, methane is the most dynamic and abundant greenhouse gas in the atmosphere. The global concentrations of atmospheric methane has increased more than doubled since pre-industrial times, with a current globally-averaged mixing ratio of ~ 1750 ppbv. Due to its high growth rate, methane brings significant effects on climate and atmospheric chemistry. There has a significant gap for variables between anthropogenic and natural sources and sinks of methane. Satellite observation of methane has been identified that it can provide the precise and accurate data globally, which sensitive to the small regional biases. We present measurements from Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) included on the European environmental satellite ENVISAT, launched on 1st of March 2002. Main objective of this study is to examine the methane distribution over Peninsular Malaysia using SCIAMACHY level-3 data. They are derived from the near-infrared nadir observations of the SCIAMACHY at the University of Bremen through scientific WFM-DOAS retrieval algorithm version 2.0.2.Maps of time averaged (yearly, tri-monthly) methane was generated and analyzed over Peninsular Malaysia for the year 2003 using PCI Geomatica 10.3 image processing software. The maps show dry-air column averaged mixing ratios of methane (denoted XCH4). It was retrieved using the interpolation technique. The concentration changes within boundary layer at all altitude levels are equally sensitive through the SCIAMACHY near-infrared nadir observations. Hence, we can make observation of methane at surface source region. The results successfully identify the area with highest and lowest concentration of methane at Peninsular Malaysia using SCIAMACHY data. Therefore, the study is suitable to examine the distribution of methane at tropical region.

  5. Vectorial mapping of noncollinear antiferromagnetic structure of semiconducting FeSe surface with spin-polarized scanning tunneling microscopy

    International Nuclear Information System (INIS)

    Antiferromagnetic semiconductors gain increasing interest due to their possible application in spintronics. Using spin polarized scanning tunneling microscopy operating in a vector field, we mapped the noncollinear antiferromagnetic spin structure of a semiconducting hexagonal FeSe surface on the atomic scale. The surface possesses an in-plane compensated Néel structure which is further confirmed by first-principles calculations

  6. Vectorial mapping of noncollinear antiferromagnetic structure of semiconducting FeSe surface with spin-polarized scanning tunneling microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, K. F.; Yang, Fang; Song, Y. R. [Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Zhang, Xiaole [Institute of Natural Sciences, Shanghai Jiao Tong University, Shanghai 200240 (China); The State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Chen, Xianfeng [The State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Liu, Canhua; Qian, Dong; Gao, C. L., E-mail: clgao@sjtu.edu.cn; Jia, Jin-Feng [Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Collaborative Innovation Center of Advanced Microstructures, Nanjing (China); Luo, Weidong, E-mail: wdluo@sjtu.edu.cn [Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Institute of Natural Sciences, Shanghai Jiao Tong University, Shanghai 200240 (China); Collaborative Innovation Center of Advanced Microstructures, Nanjing (China)

    2016-02-08

    Antiferromagnetic semiconductors gain increasing interest due to their possible application in spintronics. Using spin polarized scanning tunneling microscopy operating in a vector field, we mapped the noncollinear antiferromagnetic spin structure of a semiconducting hexagonal FeSe surface on the atomic scale. The surface possesses an in-plane compensated Néel structure which is further confirmed by first-principles calculations.

  7. Mapping metals in Parkinson's and normal brain using rapid-scanning x-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Popescu, Bogdan F Gh; George, Martin J; McCrea, Richard P E; Devon, Richard M; George, Graham N; Hanson, Akela D; Chapman, L Dean; Nichol, Helen [Department of Anatomy and Cell Biology, College of Medicine, University of Saskatchewan SK (Canada); Bergmann, Uwe; Garachtchenko, Alex V; Luening, Katharina [Stanford Synchrotron Radiation Laboratory, Menlo Park, CA (United States); Kelly, Michael E [Division of Neurosurgery, University of Saskatchewan, SK (Canada); Harder, Sheri M [Department of Medical Imaging, University of Saskatchewan, SK (Canada); Pickering, Ingrid J [Department of Geological Sciences, University of Saskatchewan, SK (Canada)], E-mail: h.nichol@usask.ca

    2009-02-07

    Rapid-scanning x-ray fluorescence (RS-XRF) is a synchrotron technology that maps multiple metals in tissues by employing unique hardware and software to increase scanning speed. RS-XRF was validated by mapping and quantifying iron, zinc and copper in brain slices from Parkinson's disease (PD) and unaffected subjects. Regions and structures in the brain were readily identified by their metal complement and each metal had a unique distribution. Many zinc-rich brain regions were low in iron and vice versa. The location and amount of iron in brain regions known to be affected in PD agreed with analyses using other methods. Sample preparation is simple and standard formalin-fixed autopsy slices are suitable. RS-XRF can simultaneously and non-destructively map and quantify multiple metals and holds great promise to reveal metal pathologies associated with PD and other neurodegenerative diseases as well as diseases of metal metabolism.

  8. Mapping Henry: Synchrotron-sourced X-ray fluorescence mapping and ultra-high-definition scanning of an early Tudor portrait of Henry VIII

    Science.gov (United States)

    Dredge, Paula; Ives, Simon; Howard, Daryl L.; Spiers, Kathryn M.; Yip, Andrew; Kenderdine, Sarah

    2015-11-01

    A portrait of Henry VIII on oak panel c. 1535 has recently undergone technical examination to inform questions regarding authorship and the painting's relationship to a group of similar works in the collections of the National Portrait Gallery, London, and the Society of Antiquaries. Due to previous conservation treatments of the painting, the conventional transmission X-radiograph image was difficult to interpret. As a result, the painting underwent high-definition X-ray fluorescence (XRF) elemental mapping on the X-ray fluorescence microscopy beamline of the Australian Synchrotron. Scans were conducted at 12.6 and 18.5 keV, below and above the lead (Pb) L edges, respectively. Typical scan parameters were 120 μm pixel size at 7 ms dwell time, with the largest scan covering an area 545 × 287 mm2 collected in 23 h (10.8 MP). XRF mapping of the panel has guided the conservation treatment of the painting and the revelation of previously obscured features. It has also provided insight into the process of making of the painting. The informative and detailed elemental maps, alongside ultra-high-definition scans of the painting undertaken before and after varnish and over-paint removal, have assisted in comparison of the finely painted details with the London paintings. The resolution offered by the combination of imaging techniques identifies pigment distribution at an extremely fine scale, enabling a new understanding of the artist's paint application.

  9. Mapping Henry: Synchrotron-sourced X-ray fluorescence mapping and ultra-high-definition scanning of an early Tudor portrait of Henry VIII

    International Nuclear Information System (INIS)

    A portrait of Henry VIII on oak panel c. 1535 has recently undergone technical examination to inform questions regarding authorship and the painting's relationship to a group of similar works in the collections of the National Portrait Gallery, London, and the Society of Antiquaries. Due to previous conservation treatments of the painting, the conventional transmission X-radiograph image was difficult to interpret. As a result, the painting underwent high-definition X-ray fluorescence (XRF) elemental mapping on the X-ray fluorescence microscopy beamline of the Australian Synchrotron. Scans were conducted at 12.6 and 18.5 keV, below and above the lead (Pb) L edges, respectively. Typical scan parameters were 120 μm pixel size at 7 ms dwell time, with the largest scan covering an area 545 x 287 mm2 collected in 23 h (10.8 MP). XRF mapping of the panel has guided the conservation treatment of the painting and the revelation of previously obscured features. It has also provided insight into the process of making of the painting. The informative and detailed elemental maps, alongside ultra-high-definition scans of the painting undertaken before and after varnish and over-paint removal, have assisted in comparison of the finely painted details with the London paintings. The resolution offered by the combination of imaging techniques identifies pigment distribution at an extremely fine scale, enabling a new understanding of the artist's paint application. (orig.)

  10. Mapping Henry: Synchrotron-sourced X-ray fluorescence mapping and ultra-high-definition scanning of an early Tudor portrait of Henry VIII

    Energy Technology Data Exchange (ETDEWEB)

    Dredge, Paula; Ives, Simon [Art Gallery of New South Wales (AGNSW), Sydney, NSW (Australia); Howard, Daryl L.; Spiers, Kathryn M. [Australian Synchrotron, Clayton, VIC (Australia); Yip, Andrew [Art Gallery of New South Wales (AGNSW), Sydney, NSW (Australia); University of New South Wales, Laboratory for Innovation in Galleries, Libraries, Archives and Museums (iGLAM), National Institute for Experimental Arts, Sydney, NSW (Australia); Kenderdine, Sarah [University of New South Wales, Laboratory for Innovation in Galleries, Libraries, Archives and Museums (iGLAM), National Institute for Experimental Arts, Sydney, NSW (Australia)

    2015-11-15

    A portrait of Henry VIII on oak panel c. 1535 has recently undergone technical examination to inform questions regarding authorship and the painting's relationship to a group of similar works in the collections of the National Portrait Gallery, London, and the Society of Antiquaries. Due to previous conservation treatments of the painting, the conventional transmission X-radiograph image was difficult to interpret. As a result, the painting underwent high-definition X-ray fluorescence (XRF) elemental mapping on the X-ray fluorescence microscopy beamline of the Australian Synchrotron. Scans were conducted at 12.6 and 18.5 keV, below and above the lead (Pb) L edges, respectively. Typical scan parameters were 120 μm pixel size at 7 ms dwell time, with the largest scan covering an area 545 x 287 mm{sup 2} collected in 23 h (10.8 MP). XRF mapping of the panel has guided the conservation treatment of the painting and the revelation of previously obscured features. It has also provided insight into the process of making of the painting. The informative and detailed elemental maps, alongside ultra-high-definition scans of the painting undertaken before and after varnish and over-paint removal, have assisted in comparison of the finely painted details with the London paintings. The resolution offered by the combination of imaging techniques identifies pigment distribution at an extremely fine scale, enabling a new understanding of the artist's paint application. (orig.)

  11. Valorization of Local Mineral Admixtures in Concretes

    Directory of Open Access Journals (Sweden)

    Boudchicha Abdelaziz

    2014-04-01

    Full Text Available This study is an extension of previous researches on mortars with mineral admixtures and super-plasticizers. In this way, the same methodology was applied to concretes and the use of mineral admixture was limited to low cost materials available in Algeria as limestone, pozzolan and blast furnace slag, with current cement and super-plasticizer. The experimental methodology used was based on the volume substitution of the cement by admixtures in mixtures with the absolute volume of the solid phases and workability preserved constant. The main results achieved showed that the super-plasticizer demand of concretes depends on the nature and the quantity of the incorporated admixture. The combined use of admixtures and super-plasticizer has generally a favourable effect on compressive strengths at 07 and 28 days at low rates of cement substitution, which vary significantly with the nature, fineness and quantity of the used admixtures. At 07 days, limestone admixtures give better improvements and reach more than 20 % of gain to the compressive strength of the reference concrete with no admixtures or super-plasticizer, at 10 % of the cement substitution and still better until 30 %. At 28 days, blast furnace slag admixtures give better improvements at 28 days and reach more than 20 % of gain to the compressive strength of the reference concrete at 20 % of the cement substitution and still better until 30 %. This contribution to the compressive strength is explained on the one hand by the reduction of the quantity of water in the mixtures at the same consistency, by the use of the super-plasticizer and on another hand by the activity of Limestone admixtures at early ages and to the latent hydraulic properties of blast furnace slag at 28 days.

  12. Mapping Natura 2000 Habitat Conservation Status in a Pannonic Salt Steppe with Airborne Laser Scanning

    Directory of Open Access Journals (Sweden)

    András Zlinszky

    2015-03-01

    Full Text Available Natura 2000 Habitat Conservation Status is currently evaluated based on fieldwork. However, this is proving to be unfeasible over large areas. The use of remote sensing is increasingly encouraged but covering the full range of ecological variables by such datasets and ensuring compatibility with the traditional assessment methodology has not been achieved yet. We aimed to test Airborne Laser Scanning (ALS as a source for mapping all variables required by the local official conservation status assessment scheme and to develop an automated method that calculates Natura 2000 conservation status at 0.5 m raster resolution for 24 km2 of Pannonic Salt Steppe habitat (code 1530. We used multi-temporal (summer and winter ALS point clouds with full-waveform recording and a density of 10 pt/m2. Some required variables were derived from ALS product rasters; others involved vegetation classification layers calculated by machine learning and fuzzy categorization. Thresholds separating favorable and unfavorable values of each variable required by the national assessment scheme were manually calibrated from 10 plots where field-based assessment was carried out. Rasters representing positive and negative scores for each input variable were integrated in a ruleset that exactly follows the Hungarian Natura 2000 assessment scheme for grasslands. Accuracy of each parameter and the final conservation status score and category was evaluated by 10 independent assessment plots. We conclude that ALS is a suitable data source for Natura 2000 assessments in grasslands, and that the national grassland assessment scheme can successfully be used as a GIS processing model for conservation status, ensuring that the output is directly comparable with traditional field based assessments.

  13. Geomorphological Mapping with Terrestrial Laser Scanning and Uav-Based Imaging

    Science.gov (United States)

    Tilly, N.; Kelterbaum, D.; Zeese, R.

    2016-06-01

    High-resolution digital elevation models (DEMs) are useful for the detailed mapping of geomorphological features. Nowadays various sensors and platforms are available to collect 3D data. The presented study compares terrestrial laser scanning (TLS) and low-cost unmanned aerial vehicles (UAV)-based imaging in terms of their usability for capturing small-scale surface structures. In October 2014 and June 2015 measurements with both systems were carried out in an episodically water-filled karst depression under pasture farming in the region of Hohenlohe (Southwest Germany). The overall aims were to establish high-resolution DEMs and monitor changes of the relief caused by dissolution and compare the advantages and drawbacks of both systems for such studies. Due to the short time between the campaigns the clear detection of temporal changes was hardly possible. However, the multi-temporal campaigns allowed an extensive investigation of the usability of both sensors under different environmental conditions. In addition to the remote sensing measurements, the coordinates of several positions in the study area were measured with a RTK-DGPS system as independent reference data sets in both campaigns. The TLS- and UAV-derived DEM heights at these positions were validated against the DGPS-derived heights. The accuracy of the TLS-derived values is supported by low mean differences between TLS and DGPS measurements while the UAV-derived models show a weaker performance. In the future years additional simultaneous measurements with both approaches under more similar vegetation conditions are necessary to detect surface movements. Moreover, by investigating the subsurface the interaction of above and below ground processes might be detected.

  14. Development of Kinematic 3D Laser Scanning System for Indoor Mapping and As-Built BIM Using Constrained SLAM

    Directory of Open Access Journals (Sweden)

    Jaehoon Jung

    2015-10-01

    Full Text Available The growing interest and use of indoor mapping is driving a demand for improved data-acquisition facility, efficiency and productivity in the era of the Building Information Model (BIM. The conventional static laser scanning method suffers from some limitations on its operability in complex indoor environments, due to the presence of occlusions. Full scanning of indoor spaces without loss of information requires that surveyors change the scanner position many times, which incurs extra work for registration of each scanned point cloud. Alternatively, a kinematic 3D laser scanning system, proposed herein, uses line-feature-based Simultaneous Localization and Mapping (SLAM technique for continuous mapping. Moreover, to reduce the uncertainty of line-feature extraction, we incorporated constrained adjustment based on an assumption made with respect to typical indoor environments: that the main structures are formed of parallel or orthogonal line features. The superiority of the proposed constrained adjustment is its reduction for uncertainties of the adjusted lines, leading to successful data association process. In the present study, kinematic scanning with and without constrained adjustment were comparatively evaluated in two test sites, and the results confirmed the effectiveness of the proposed system. The accuracy of the 3D mapping result was additionally evaluated by comparison with the reference points acquired by a total station: the Euclidean average distance error was 0.034 m for the seminar room and 0.043 m for the corridor, which satisfied the error tolerance for point cloud acquisition (0.051 m according to the guidelines of the General Services Administration for BIM accuracy.

  15. High-Performance Grouting Mortar Based on Mineral Admixtures

    Directory of Open Access Journals (Sweden)

    Cong Ma

    2015-01-01

    Full Text Available A study on high-performance grouting mortar is reported. The common mortar was modified by mineral admixtures such as gypsum, bauxite, and alunite. The effects of mineral admixtures on the fluidity, setting time, expansion, strength, and other properties of mortar were evaluated experimentally. The microstructure of the modified mortar was characterized by X-ray diffraction, scanning electron microscopy, and mercury intrusion porosimetry. Moreover, the expansive performance and strength of the grouting mortar were verified by anchor pullout test. The results show that the best conditions for gypsum-bauxite grouting mortar are as follows: a water-to-binder ratio of 0.3, a mineral admixture content of ~15%, and a molar ratio K of 2. The ultimate bearing capacity of the gypsum-bauxite grouting mortar anchor increased by 39.6% compared to the common mortar anchor. The gypsum-bauxite grouting mortar has good fluidity, quick-setting, microexpansion, early strength, and high strength performances.

  16. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    Energy Technology Data Exchange (ETDEWEB)

    Mendrik, Adrienne M; Van Ginneken, Bram; Viergever, Max A [Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands); Vonken, Evert-jan; De Jong, Hugo W; Riordan, Alan; Van Seeters, Tom; Smit, Ewoud J; Prokop, Mathias, E-mail: a.m.mendrik@gmail.com [Radiology Department, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands)

    2011-07-07

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

  17. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    International Nuclear Information System (INIS)

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

  18. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    Science.gov (United States)

    Mendrik, Adriënne M.; Vonken, Evert-jan; van Ginneken, Bram; de Jong, Hugo W.; Riordan, Alan; van Seeters, Tom; Smit, Ewoud J.; Viergever, Max A.; Prokop, Mathias

    2011-07-01

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

  19. Multiple scanning electrochemical microscopy mapping of tyrosinase in micro-contact printed fruit samples on polyvinylidene fluoride membrane

    OpenAIRE

    Lin, Tzu-En; Cortes-Salazar, Fernando; Lesch, Andreas; Qiao, Liang; Bondarenko, Alexandra; Girault, Hubert

    2015-01-01

    Herein, we introduce three orthogonal and compatible methods for detecting tyrosinase, a key factor in fruit browning and skin disorders, with high spatial resolution by means of scanning electrochemical microscopy (SECM). All methods are performed subsequently on the same substrate area providing a wide range of relevant information. The first SECM approach that relies on the mapping of a differential pore oxygen concentration induced by the local hydrophobic changes that the adsorption of t...

  20. Area-Based Mapping of Defoliation of Scots Pine Stands Using Airborne Scanning LiDAR

    OpenAIRE

    Hannu Hyyppä; Michael A. Wulder; Juha Hyyppä; Ville Kankare; Markus Holopainen; Mikko Vastaranta; Päivi Lyytikäinen-Saarenmaa; Tuula Kantola

    2013-01-01

    The mapping of changes in the distribution of insect-caused forest damage remains an important forest monitoring application and challenge. Efficient and accurate methods are required for mapping and monitoring changes in insect defoliation to inform forest management and reporting activities. In this research, we develop and evaluate a LiDAR-driven (Light Detection And Ranging) approach for mapping defoliation caused by the Common pine sawfly (Diprion pini L.). Our method requires plot-level...

  1. Graph Structure-Based Simultaneous Localization and Mapping Using a Hybrid Method of 2D Laser Scan and Monocular Camera Image in Environments with Laser Scan Ambiguity.

    Science.gov (United States)

    Oh, Taekjun; Lee, Donghwa; Kim, Hyungjin; Myung, Hyun

    2015-01-01

    Localization is an essential issue for robot navigation, allowing the robot to perform tasks autonomously. However, in environments with laser scan ambiguity, such as long corridors, the conventional SLAM (simultaneous localization and mapping) algorithms exploiting a laser scanner may not estimate the robot pose robustly. To resolve this problem, we propose a novel localization approach based on a hybrid method incorporating a 2D laser scanner and a monocular camera in the framework of a graph structure-based SLAM. 3D coordinates of image feature points are acquired through the hybrid method, with the assumption that the wall is normal to the ground and vertically flat. However, this assumption can be relieved, because the subsequent feature matching process rejects the outliers on an inclined or non-flat wall. Through graph optimization with constraints generated by the hybrid method, the final robot pose is estimated. To verify the effectiveness of the proposed method, real experiments were conducted in an indoor environment with a long corridor. The experimental results were compared with those of the conventional GMappingapproach. The results demonstrate that it is possible to localize the robot in environments with laser scan ambiguity in real time, and the performance of the proposed method is superior to that of the conventional approach. PMID:26151203

  2. Graph Structure-Based Simultaneous Localization and Mapping Using a Hybrid Method of 2D Laser Scan and Monocular Camera Image in Environments with Laser Scan Ambiguity

    Directory of Open Access Journals (Sweden)

    Taekjun Oh

    2015-07-01

    Full Text Available Localization is an essential issue for robot navigation, allowing the robot to perform tasks autonomously. However, in environments with laser scan ambiguity, such as long corridors, the conventional SLAM (simultaneous localization and mapping algorithms exploiting a laser scanner may not estimate the robot pose robustly. To resolve this problem, we propose a novel localization approach based on a hybrid method incorporating a 2D laser scanner and a monocular camera in the framework of a graph structure-based SLAM. 3D coordinates of image feature points are acquired through the hybrid method, with the assumption that the wall is normal to the ground and vertically flat. However, this assumption can be relieved, because the subsequent feature matching process rejects the outliers on an inclined or non-flat wall. Through graph optimization with constraints generated by the hybrid method, the final robot pose is estimated. To verify the effectiveness of the proposed method, real experiments were conducted in an indoor environment with a long corridor. The experimental results were compared with those of the conventional GMappingapproach. The results demonstrate that it is possible to localize the robot in environments with laser scan ambiguity in real time, and the performance of the proposed method is superior to that of the conventional approach.

  3. Graph Structure-Based Simultaneous Localization and Mapping Using a Hybrid Method of 2D Laser Scan and Monocular Camera Image in Environments with Laser Scan Ambiguity.

    Science.gov (United States)

    Oh, Taekjun; Lee, Donghwa; Kim, Hyungjin; Myung, Hyun

    2015-07-03

    Localization is an essential issue for robot navigation, allowing the robot to perform tasks autonomously. However, in environments with laser scan ambiguity, such as long corridors, the conventional SLAM (simultaneous localization and mapping) algorithms exploiting a laser scanner may not estimate the robot pose robustly. To resolve this problem, we propose a novel localization approach based on a hybrid method incorporating a 2D laser scanner and a monocular camera in the framework of a graph structure-based SLAM. 3D coordinates of image feature points are acquired through the hybrid method, with the assumption that the wall is normal to the ground and vertically flat. However, this assumption can be relieved, because the subsequent feature matching process rejects the outliers on an inclined or non-flat wall. Through graph optimization with constraints generated by the hybrid method, the final robot pose is estimated. To verify the effectiveness of the proposed method, real experiments were conducted in an indoor environment with a long corridor. The experimental results were compared with those of the conventional GMappingapproach. The results demonstrate that it is possible to localize the robot in environments with laser scan ambiguity in real time, and the performance of the proposed method is superior to that of the conventional approach.

  4. 3D chemical mapping: application of scanning transmission (soft) X-ray microscopy (STXM) in combination with angle-scan tomography in bio-, geo-, and environmental sciences.

    Science.gov (United States)

    Obst, Martin; Schmid, Gregor

    2014-01-01

    The identification of environmental processes and mechanisms often requires information on the organochemical and inorganic composition of specimens at high spatial resolution. X-ray spectroscopy (XAS) performed in the soft X-ray range (100-2,200 eV) provides chemical speciation information for elements that are of high biogeochemical relevance such as carbon, nitrogen, and oxygen but also includes transition metals such as iron, manganese, or nickel. Synchrotron-based scanning transmission X-ray microscopy (STXM) combines XAS with high resolution mapping on the 20-nm scale. This provides two-dimensional (2D) quantitative information about the distribution of chemical species such as organic macromolecules, metals, or mineral phases within environmental samples. Furthermore, the combination of STXM with angle-scan tomography allows for three-dimensional (3D) spectromicroscopic analysis of bio-, geo-, or environmental samples. For the acquisition of STXM tomography data, the sample is rotated around an axis perpendicular to the X-ray beam. Various sample preparation approaches such as stripes cut from TEM grids or the preparation of wet cells allow for preparing environmentally relevant specimens in a dry or in a fully hydrated state for 2D and 3D STXM measurements. In this chapter we give a short overview about the principles of STXM, its application to environmental sciences, different preparation techniques, and the analysis and 3D reconstruction of STXM tomography data.

  5. Total quantitative recording of elemental maps and spectra with a scanning microprobe

    International Nuclear Information System (INIS)

    A system of data recording and analysis has been developed by means of which simultaneously all data from a scanning instrument such as a microprobe can be quantitatively recorded and permanently stored, including spectral outputs from several detectors. Only one scanning operation is required on the specimen. Analysis is then performed on the stored data, which contain quantitative information on distributions of all elements and spectra of all regions

  6. Mapping Morphological and Structural Properties of Lead Halide Perovskites by Scanning Nanofocus XRD

    OpenAIRE

    Lilliu, Samuele; Dane, Thomas G.; Griffin, Jonathan; Alsari, Mejd; Barrows, Alexander T.; Dahlem, Marcus S.; Friend, Richard H.; Lidzey, David G.; Macdonald, J. Emyr

    2016-01-01

    Scanning nanofocus X-ray diffraction (nXRD) performed at a synchrotron is used for the first time to simultaneously probe the morphology and the structural properties of spin-coated CH3NH3PbI3 (MAPI) perovskite films for photovoltaic devices. MAPI films are spin-coated on a Si/SiO2/PEDOT:PSS substrate held at different temperatures during the deposition in order to tune the perovskite film coverage, and then investigated by nXRD, scanning electron microscopy (SEM) and grazing incidence wide a...

  7. Effect of Functional Chemical Admixtures on the Performance of Cement Asphalt Mortar Used in Ballastless Track

    Institute of Scientific and Technical Information of China (English)

    JIANG Jinyang; SHE Wei; LI Wei; PAN Li

    2015-01-01

    Chemical admixtures are of paramount importance to the performance of modern cement based composites. In this paper, we performed a series of tests to investigate the effects of chemical admixtures on the cement asphalt mortar (CA mortar), i e, compressive strength, frost resistance, permeability, fatigue resistance, pore structure and microstructure. In particular, two types of chemical admixtures were tested,i e, defoamer (tributyl phosphate (TBP)) and polycarboxylate superplasticizer (PS). The results indicate that the addition of TBP and PS eliminates big bubbles and promotes small non-connected pores forming in matrix. Besides, an optimum dosage of TBP and PS may be determined with respect to the frost resistance, permeability and fatigue resistance of CA mortar. Further elaborative discussions are presented as well as experimental evidences from mercury intrusion porosimetry, scanning electron microscopy and energy dispersive spectroscopy.

  8. Effects of GH Admixture on the Early Strength of Fly Ash Concrete and Mortar

    Institute of Scientific and Technical Information of China (English)

    KANG Jingfu; WANG Xiufen

    2008-01-01

    The enhancement effects of GH admixture on the early strengths of fly ash concrete and mortar were studied, and the mechanism was analyzed by X-ray diffraction (XRD) and scanning electro microscope (SEM). Experimental results show that, by the incorporation of GH admixture, both of cement hydration and pozzolanic reaction of fly ash are accelerated, the strengths of fly ash concrete and mortar are enhanced noticeably, especially the early strength. With a mixture design of 200 kg/m3 OPC (Ordinary Portland Cement), 200 kg/m3 fly ash and 50 kg/m3 GH admixture, the strength of concrete at 1 d, 3 d and 28 d reaches 25 Mpa, 50 Mpa and 70 Mpa respectively.

  9. Test of the Capability of Laser Line Scan Technology to Support Benthic Habitat Mapping in Coral Reef Ecosystems, Maui Island, November 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The utility of Laser Line Scan (LLS) Technology for optical validation of benthic habitat map data from coral reef ecosystems was tested with a deployment of a...

  10. Submolecular Electronic Mapping of Single Cysteine Molecules by in Situ Scanning Tunneling Imaging

    DEFF Research Database (Denmark)

    Zhang, Jingdong; Chi, Qijin; Nazmutdinov, R. R.;

    2009-01-01

    We have used L-Cysteine (Cys) as a model system to study the surface electronic structures of single molecules at the submolecular level in aqueous buffer solution by a combination of electrochemical scanning tunneling microscopy (in situ STM), electrochemistry including voltammetry and chronocou...

  11. High-field flux mapping of (RE)BCO bulk superconductors-Development of an in situ scanning system

    Energy Technology Data Exchange (ETDEWEB)

    Withnell, T.D. [Superconductivity Group, Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ (United Kingdom)], E-mail: tdw25@cantab.net; Hari-Babu, N.; Ganney, I.; Dennis, A.; Cardwell, D.A. [Superconductivity Group, Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ (United Kingdom)

    2008-06-15

    Flux mapping of Y-Ba-Cu-O (YBCO) melt-processed, bulk high-temperature superconductors (HTS) is used to visualise the profile of trapped magnetic field on a magnetised sample and to measure the extent of current flow, and hence field penetration, within the bulk microstructure. Grain structure and defects below the sample surface are observed non-destructively by this technique. This paper outlines the design, development and construction of a novel, in situ Hall scanning system using an 8 T magnet and variable temperature insert (VTI). This system is then used to characterise the field trapping properties of bulk samples for different applied field history.

  12. Mapping Infrared Data on Terrestrial Laser Scanning 3D Models of Buildings

    OpenAIRE

    Mattia Previtali; Elisabetta Rosina; Marco Scaioni; Luigi Barazzetti; Mario Ivan Alba

    2011-01-01

    A new 3D acquisition and processing procedure to map RGB, thermal IR and near infrared images (NIR) on a detailed 3D model of a building is presented. The combination and fusion of different data sources allows the generation of 3D thermal data useful for different purposes such as localization, visualization, and analysis of anomalies in contemporary architecture. The classic approach, which is currently used to map IR images on 3D models, is based on the direct registration of each single i...

  13. Three-dimensional acousto-optic mapping using planar scanning with ultrasound bursts

    NARCIS (Netherlands)

    Bratchenia, A.; Molenaar, R.; Kooyman, R.P.H.; Oraevsky, Alexander; Wang, Lihong V.

    2009-01-01

    We have investigated the application of AO sensing for quantitative three-dimensional mapping of tissue-mimicking phantoms. An Intralipid phantom, which contains a turbid absorber, confined in a silicone tube, was used. Multiply scattered pulsed laser light was modulated by ultrasonic bursts focused

  14. Low-cost Mobile Laser Scanning and its Feasibility for Environmental Mapping

    OpenAIRE

    Jaakkola, Anttoni

    2015-01-01

    Mobile laser scanning is a measurement technology that combines accurate positioning and attitude information from navigation satellites and inertial sensors with distance measurements from a laser scanner into a point cloud that represents the geometry of the environment surrounding the measurement platform. This geometrical information can be utilized in a variety of applications ranging from 3D city modelling and infrastructure maintenance to forestry and environmental monitoring. In th...

  15. Mapping Liquid-liquid protein phase separation using ultra-fast-scanning fluorescence correlation spectroscopy

    Science.gov (United States)

    Wei, Ming-Tzo; Elbaum-Garfinkle, Shana; Arnold, Craig B.; Priestley, Rodney D.; Brangwynne, Clifford P.

    Intrinsically disordered proteins (IDPs) are an understudied class of proteins that play important roles in a wide variety of biological processes in cells. We've previously shown that the C. elegans IDP LAF-1 phase separates into P granule-like droplets in vitro. However, the physics of the condensed phase remains poorly understood. Here, we use a novel technique, ultra-fast-scanning fluorescence correlation spectroscopy, to study the nano-scale rheological properties of LAF-1 droplets. Ultra-fast-scanning FCS uses a tunable acoustic gradient index of refraction (TAG) lens with an oil immersion objective to control axial movement of the focal point over a length of several micrometers at frequencies of 70kHz. Using ultra-fast-scanning FCS allows for the accurate determination of molecular concentrations and their diffusion coefficient, when the particle is passing through an excitation volume. Our work reveals an asymmetric LAF-1 phase diagram, and demonstrates that LAF-1 droplets are purely viscous phases which are highly tunable by salt concentration.

  16. Digital mapping of side-scan sonar data with the Woods Hole Image Processing System software

    Science.gov (United States)

    Paskevich, Valerie F.

    1992-01-01

    Since 1985, the Branch of Atlantic Marine Geology has been involved in collecting, processing and digitally mosaicking high and low resolution sidescan sonar data. In the past, processing and digital mosaicking has been accomplished with a dedicated, shore-based computer system. Recent development of a UNIX-based image-processing software system includes a series of task specific programs for pre-processing sidescan sonar data. To extend the capabilities of the UNIX-based programs, development of digital mapping techniques have been developed. This report describes the initial development of an automated digital mapping procedure. Included is a description of the programs and steps required to complete the digital mosaicking on a UNIXbased computer system, and a comparison of techniques that the user may wish to select.

  17. A technique on automatic land-use database reconstruction based on scanning land-use map

    Institute of Scientific and Technical Information of China (English)

    LI; Xiaojuan; GONG; Huili; YIN; Lianwang; SUN; Yonghua; YANG; Lingli; WANG; Yanggang

    2006-01-01

    Although a land-cover database is very important to national land use including urban planning and land-use management, it is very laborious and time-consuming to build through digitization of paper land-use maps (1:10000) and data input by hand. Here we propose a new, high-level, automatic technique to build a land-use database, which has proved useful and practical in building a land-use database of Baotou City.

  18. Mapping Cd²⁺-induced membrane permeability changes of single live cells by means of scanning electrochemical microscopy.

    Science.gov (United States)

    Filice, Fraser P; Li, Michelle S M; Henderson, Jeffrey D; Ding, Zhifeng

    2016-02-18

    Scanning Electrochemical Microscopy (SECM) is a powerful, non-invasive, analytical methodology that can be used to investigate live cell membrane permeability. Depth scan SECM imaging allowed for the generation of 2D current maps of live cells relative to electrode position in the x-z or y-z plane. Depending on resolution, one depth scan image can contain hundreds of probe approach curves (PACs). Individual PACs were obtained by simply extracting vertical cross-sections from the 2D image. These experimental PACs were overlaid onto theoretically generated PACs simulated at specific geometry conditions. Simulations were carried out using 3D models in COMSOL Multiphysics to determine the cell membrane permeability coefficients at different locations on the surface of the cells. Common in literature, theoretical PACs are generated using a 2D axially symmetric geometry. This saves on both compute time and memory utilization. However, due to symmetry limitations of the model, only one experimental PAC right above the cell can be matched with simulated PAC data. Full 3D models in this article were developed for the SECM system of live cells, allowing all experimental PACs over the entire cell to become usable. Cd(2+)-induced membrane permeability changes of single human bladder (T24) cells were investigated at several positions above the cell, displaced from the central axis. The experimental T24 cells under study were incubated with Cd(2+) in varying concentrations. It is experimentally observed that 50 and 100 μM Cd(2+) caused a decrease in membrane permeability, which was uniform across all locations over the cell regardless of Cd(2+) concentration. The Cd(2+) was found to have detrimental effects on the cell, with cells shrinking in size and volume, and the membrane permeability decreasing. A mapping technique for the analysis of the cell membrane permeability under the Cd(2+) stress is realized by the methodology presented. PMID:26826690

  19. Study on incidence of pulmonary embolism in patients with cardiac pacemakers using lung perfusion mapping and ventilation scanning

    International Nuclear Information System (INIS)

    We investigated pulmonary perfusion mapping and ventilation scanning employing 99mTC-MMA and 81mKr-Gas in patients with DDD and VVI cardiac pacemaker implantation. In 51 cases among 175 patients we observed some defects which matched the results from lung perfusion scanning in the pulmonary segments and sub-segments. These were diagnosed as pulmonary embolism after the possibility of other pulmonary diseases was rejected. The incidence rate of pulmonary embolism in patients with VVI (Ventricular pacing/sensing, inhibited type) pacemakers was 47 out of 138, or 34.1%, especially for those who received a pulmonary scanning examination whithin 6 months after pacemaker implantation. In contrast, those who were examined after 6 months had lower rates as well as chronological factors. The incidence rate of pulmonary embolism in 37 patients with DDD (Double chamber pacing/sensing, double modes of response) pacemakers was 10.8%, considerably lower than that for patients with VVI pacemakers. Therefore, one main factor of pulmonary embolism in patients with pacemakers could be the non-physiological phase of the contractions of both atria and ventricles. Other factors, such as the presence of foreign bodies in the endocardium, aging, and hypertension, could also promote pulmonary embolism. (author)

  20. A Genome Scan for Modifiers of Age at Onset in Huntington Disease: The HD MAPS Study

    OpenAIRE

    Li, Jian-Liang; Hayden, Michael R.; Almqvist, Elisabeth W.; Brinkman, Ryan R; Durr, Alexandra; Dodé, Catherine; Morrison, Patrick J.; Suchowersky, Oksana; Ross, Christopher A.; Margolis, Russell L.; Rosenblatt, Adam; Gómez-Tortosa, Estrella; Cabrero, David Mayo; Novelletto, Andrea; Frontali, Marina

    2003-01-01

    Huntington disease (HD) is caused by the expansion of a CAG repeat within the coding region of a novel gene on 4p16.3. Although the variation in age at onset is partly explained by the size of the expanded repeat, the unexplained variation in age at onset is strongly heritable (h2=0.56), which suggests that other genes modify the age at onset of HD. To identify these modifier loci, we performed a 10-cM density genomewide scan in 629 affected sibling pairs (295 pedigrees and 695 individuals), ...

  1. Atomic-scale mapping of electronic structures across heterointerfaces by cross-sectional scanning tunneling microscopy

    International Nuclear Information System (INIS)

    Interfacial science has received much attention recently based on the development of state-of-the-art analytical tools that can create and manipulate the charge, spin, orbital, and lattice degrees of freedom at interfaces. Motivated by the importance of nanoscale interfacial science that governs device operation, we present a technique to probe the electronic characteristics of heterointerfaces with atomic resolution. In this work, the interfacial characteristics of heteroepitaxial structures are investigated and the fundamental mechanisms that pertain in these systems are elucidated through cross-sectional scanning tunneling microscopy (XSTM). The XSTM technique is employed here to directly observe epitaxial interfacial structures and probe local electronic properties with atomic-level capability. Scanning tunneling microscopy and spectroscopy experiments with atomic precision provide insight into the origin and spatial distribution of electronic properties across heterointerfaces. The first part of this report provides a brief description of the cleavage technique and spectroscopy analysis in XSTM measurements. The second part addresses interfacial electronic structures of several model heterostructures in current condensed matter research using XSTM. Topics to be discussed include high-κ‘s/III–V’s semiconductors, polymer heterojunctions, and complex oxide heterostructures, which are all material systems whose investigation using this technique is expected to benefit the research community. Finally, practical aspects and perspectives of using XSTM in interface science are presented. (topical review)

  2. Nanoscale magnetic field mapping with a single spin scanning probe magnetometer

    Energy Technology Data Exchange (ETDEWEB)

    Rondin, L.; Tetienne, J.-P.; Spinicelli, P.; Roch, J.-F.; Jacques, V. [Laboratoire de Photonique Quantique et Moleculaire, Ecole Normale Superieure de Cachan and CNRS UMR 8537, 94235 Cachan Cedex (France); Dal Savio, C.; Karrai, K. [Attocube systems AG, Koeniginstrasse 11A RGB, Munich 80539 (Germany); Dantelle, G. [Laboratoire de Physique de la Matiere Condensee, Ecole Polytechnique and CNRS UMR 7643, 91128 Palaiseau (France); Thiaville, A.; Rohart, S. [Laboratoire de Physique des Solides, Universite Paris-Sud and CNRS UMR 8502, 91405 Orsay (France)

    2012-04-09

    We demonstrate quantitative magnetic field mapping with nanoscale resolution, by applying a lock-in technique on the electron spin resonance frequency of a single nitrogen-vacancy defect placed at the apex of an atomic force microscope tip. In addition, we report an all-optical magnetic imaging technique which is sensitive to large off-axis magnetic fields, thus extending the operation range of diamond-based magnetometry. Both techniques are illustrated by using a magnetic hard disk as a test sample. Owing to the non-perturbing and quantitative nature of the magnetic probe, this work should open up numerous perspectives in nanomagnetism and spintronics.

  3. Mapping interfacial chemistry induced variations in protein adsorption with scanning force microscopy.

    Science.gov (United States)

    Ta, T C; McDermott, M T

    2000-06-01

    In this work, we demonstrate the sensitivity of scanning force microscopy (SFM), operated in friction force mode, to adsorbed protein conformation or orientation. We employ patterned films of methyl- and carboxylate-terminated alkanethiolate monolayers on gold as substrates for protein adsorption to observe the effect of each functional group in the same image. Infrared spectroscopic and SFM studies of bovine fibrinogen (BFG) adsorption to single-component monolayers indicate that complete films of BFG that are stable to imaging are formed at each functional group. After adsorption of BFG to a patterned monolayer, we observe a contrast in friction images due to differences in adsorbed BFG conformation or orientation induced by each functional group. We also observe frictional contrast in films of other proteins adsorbed on patterned monolayers. These observations lead to the conclusion that SFM-measured friction is sensitive to adsorbed protein state.

  4. A cost-effective laser scanning method for mapping stream channel geometry and roughness

    Science.gov (United States)

    Lam, Norris; Nathanson, Marcus; Lundgren, Niclas; Rehnström, Robin; Lyon, Steve

    2015-04-01

    In this pilot project, we combine an Arduino Uno and SICK LMS111 outdoor laser ranging camera to acquire high resolution topographic area scans for a stream channel. The microprocessor and imaging system was installed in a custom gondola and suspended from a wire cable system. To demonstrate the systems capabilities for capturing stream channel topography, a small stream (stream channel resulted in a point spacing of 4mm and a point cloud density of 5600 points/m2 for the 5m by 2m area. A grain size distribution of the streambed material was extracted from the point cloud using a moving window, local maxima search algorithm. The median, 84th and 90th percentiles (common metrics to describe channel roughness) of this distribution were found to be within the range of measured values while the largest modelled element was approximately 35% smaller than its measured counterpart. The laser scanning system captured grain sizes between 30mm and 255mm (coarse gravel/pebbles and boulders based on the Wentworth (1922) scale). This demonstrates that our system was capable of resolving both large-scale geometry (e.g. bed slope and stream channel width) and small-scale channel roughness elements (e.g. coarse gravel/pebbles and boulders) for the study area. We further show that the point cloud resolution is suitable for estimating ecohydraulic parameters such as Manning's n and hydraulic radius. Although more work is needed to fine-tune our system's design, these preliminary results are encouraging, specifically for those with a limited operational budget.

  5. Population Genomics of sub-saharan Drosophila melanogaster: African diversity and non-African admixture.

    Directory of Open Access Journals (Sweden)

    John E Pool

    Full Text Available Drosophila melanogaster has played a pivotal role in the development of modern population genetics. However, many basic questions regarding the demographic and adaptive history of this species remain unresolved. We report the genome sequencing of 139 wild-derived strains of D. melanogaster, representing 22 population samples from the sub-Saharan ancestral range of this species, along with one European population. Most genomes were sequenced above 25X depth from haploid embryos. Results indicated a pervasive influence of non-African admixture in many African populations, motivating the development and application of a novel admixture detection method. Admixture proportions varied among populations, with greater admixture in urban locations. Admixture levels also varied across the genome, with localized peaks and valleys suggestive of a non-neutral introgression process. Genomes from the same location differed starkly in ancestry, suggesting that isolation mechanisms may exist within African populations. After removing putatively admixed genomic segments, the greatest genetic diversity was observed in southern Africa (e.g. Zambia, while diversity in other populations was largely consistent with a geographic expansion from this potentially ancestral region. The European population showed different levels of diversity reduction on each chromosome arm, and some African populations displayed chromosome arm-specific diversity reductions. Inversions in the European sample were associated with strong elevations in diversity across chromosome arms. Genomic scans were conducted to identify loci that may represent targets of positive selection within an African population, between African populations, and between European and African populations. A disproportionate number of candidate selective sweep regions were located near genes with varied roles in gene regulation. Outliers for Europe-Africa F(ST were found to be enriched in genomic regions of locally

  6. State of the water in crosslinked sulfonated poly(ether ether ketone). Two-dimensional differential scanning calorimetry correlation mapping

    International Nuclear Information System (INIS)

    Highlights: • 2D-DSC mapping was applied to analyze the heat flow responses of hydrated crosslinked sPEEK. • Two types of loosely bond water were observed. • The first was bond to the sulfonic acid groups and increased with ion exchange capacity. • The second was attributed to the polar groups introduced by ions irradiation and increased with crosslinking degree. • DSC combined with 2D mapping provides a powerful tool for polymer structural determination. - Abstract: This paper reports the first application of two-dimensional differential scanning calorimetry correlation mapping, 2D-DSC-CM to analyze the heat flow responses of sulphonated poly(ether ether ketone), sPEEK, films having different ion exchange capacity and degrees of crosslinks. With the help of high resolution and high sensitivity of 2D-DSC-CM, it was possible to locate two types of loosely bound water within the structure of crosslinked sPEEK. The first was bound to the sulfonic acid groups and dependent on the ion exchange capacity of the sPEEK. The second was bound to other polar groups, either introduced by irradiation with ions and dependent on the crosslinking degree or present in the polymer such as the carbonyl groups or terminal units. The results suggest that the ability of the sulfonic acid groups in the crosslinked sPEEK membranes to adsorb water molecules is increased by crosslinking, probably due to the better close packing efficiency of the crosslinked samples. DSC combined with 2D correlation mapping provides a fast and powerful tool for polymer structural determination

  7. State of the water in crosslinked sulfonated poly(ether ether ketone). Two-dimensional differential scanning calorimetry correlation mapping

    Energy Technology Data Exchange (ETDEWEB)

    Al Lafi, Abdul G. [Department of Chemistry, Atomic Energy Commission, Damascus, P.O. Box 6091 (Syrian Arab Republic); Hay, James N., E-mail: cscientific9@aec.org.sy [The School of Metallurgy and Materials, College of Physical Sciences and Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2015-07-20

    Highlights: • 2D-DSC mapping was applied to analyze the heat flow responses of hydrated crosslinked sPEEK. • Two types of loosely bond water were observed. • The first was bond to the sulfonic acid groups and increased with ion exchange capacity. • The second was attributed to the polar groups introduced by ions irradiation and increased with crosslinking degree. • DSC combined with 2D mapping provides a powerful tool for polymer structural determination. - Abstract: This paper reports the first application of two-dimensional differential scanning calorimetry correlation mapping, 2D-DSC-CM to analyze the heat flow responses of sulphonated poly(ether ether ketone), sPEEK, films having different ion exchange capacity and degrees of crosslinks. With the help of high resolution and high sensitivity of 2D-DSC-CM, it was possible to locate two types of loosely bound water within the structure of crosslinked sPEEK. The first was bound to the sulfonic acid groups and dependent on the ion exchange capacity of the sPEEK. The second was bound to other polar groups, either introduced by irradiation with ions and dependent on the crosslinking degree or present in the polymer such as the carbonyl groups or terminal units. The results suggest that the ability of the sulfonic acid groups in the crosslinked sPEEK membranes to adsorb water molecules is increased by crosslinking, probably due to the better close packing efficiency of the crosslinked samples. DSC combined with 2D correlation mapping provides a fast and powerful tool for polymer structural determination.

  8. Permeability mapping in porous media by magnetization prepared centric-scan SPRITE

    Science.gov (United States)

    Romanenko, Konstantin V.; Balcom, Bruce J.

    2011-02-01

    The ability of porous media to transmit fluids is commonly referred to as permeability. The concept of permeability is central for hydrocarbon recovery from petroleum reservoirs and for studies of groundwater flow in aquifers. Spatially resolved measurements of permeability are of great significance for fluid dynamics studies. A convenient concept of local Darcy's law is suggested for parallel flow systems. The product of porosity and mean velocity images in the plane across the average flow direction is directly proportional to permeability. Single Point Ramped Imaging with T 1 Enhancement (SPRITE) permits reliable quantification of local fluid content and flow in porous media. It is particularly advantageous for reservoir rocks characterized by fast magnetic relaxation of a saturating fluid. Velocity encoding using the Cotts pulsed field gradient scheme improves the accuracy of measured flow parameters. The method is illustrated through measurements of 2D permeability maps in a capillary bundle, glass bead packs and composite sandstone samples.

  9. Extended focused imaging and depth map reconstruction in optical scanning holography.

    Science.gov (United States)

    Ren, Zhenbo; Chen, Ni; Lam, Edmund Y

    2016-02-10

    In conventional microscopy, specimens lying within the depth of field are clearly recorded whereas other parts are blurry. Although digital holographic microscopy allows post-processing on holograms to reconstruct multifocus images, it suffers from defocus noise as a traditional microscope in numerical reconstruction. In this paper, we demonstrate a method that can achieve extended focused imaging (EFI) and reconstruct a depth map (DM) of three-dimensional (3D) objects. We first use a depth-from-focus algorithm to create a DM for each pixel based on entropy minimization. Then we show how to achieve EFI of the whole 3D scene computationally. Simulation and experimental results involving objects with multiple axial sections are presented to validate the proposed approach. PMID:26906373

  10. Genetic admixture and population substructure in Guanacaste Costa Rica.

    Directory of Open Access Journals (Sweden)

    Zhaoming Wang

    Full Text Available The population of Costa Rica (CR represents an admixture of major continental populations. An investigation of the CR population structure would provide an important foundation for mapping genetic variants underlying common diseases and traits. We conducted an analysis of 1,301 women from the Guanacaste region of CR using 27,904 single nucleotide polymorphisms (SNPs genotyped on a custom Illumina InfiniumII iSelect chip. The program STRUCTURE was used to compare the CR Guanacaste sample with four continental reference samples, including HapMap Europeans (CEU, East Asians (JPT+CHB, West African Yoruba (YRI, as well as Native Americans (NA from the Illumina iControl database. Our results show that the CR Guanacaste sample comprises a three-way admixture estimated to be 43% European, 38% Native American and 15% West African. An estimated 4% residual Asian ancestry may be within the error range. Results from principal components analysis reveal a correlation between genetic and geographic distance. The magnitude of linkage disequilibrium (LD measured by the number of tagging SNPs required to cover the same region in the genome in the CR Guanacaste sample appeared to be weaker than that observed in CEU, JPT+CHB and NA reference samples but stronger than that of the HapMap YRI sample. Based on the clustering pattern observed in both STRUCTURE and principal components analysis, two subpopulations were identified that differ by approximately 20% in LD block size averaged over all LD blocks identified by Haploview. We also show in a simulated association study conducted within the two subpopulations, that the failure to account for population stratification (PS could lead to a noticeable inflation in the false positive rate. However, we further demonstrate that existing PS adjustment approaches can reduce the inflation to an acceptable level for gene discovery.

  11. African ancestry and its correlation to type 2 diabetes in African Americans: a genetic admixture analysis in three U.S. population cohorts.

    Directory of Open Access Journals (Sweden)

    Ching-Yu Cheng

    Full Text Available The risk of type 2 diabetes is approximately 2-fold higher in African Americans than in European Americans even after adjusting for known environmental risk factors, including socioeconomic status (SES, suggesting that genetic factors may explain some of this population difference in disease risk. However, relatively few genetic studies have examined this hypothesis in a large sample of African Americans with and without diabetes. Therefore, we performed an admixture analysis using 2,189 ancestry-informative markers in 7,021 African Americans (2,373 with type 2 diabetes and 4,648 without from the Atherosclerosis Risk in Communities Study, the Jackson Heart Study, and the Multiethnic Cohort to 1 determine the association of type 2 diabetes and its related quantitative traits with African ancestry controlling for measures of SES and 2 identify genetic loci for type 2 diabetes through a genome-wide admixture mapping scan. The median percentage of African ancestry of diabetic participants was slightly greater than that of non-diabetic participants (study-adjusted difference = 1.6%, P<0.001. The odds ratio for diabetes comparing participants in the highest vs. lowest tertile of African ancestry was 1.33 (95% confidence interval 1.13-1.55, after adjustment for age, sex, study, body mass index (BMI, and SES. Admixture scans identified two potential loci for diabetes at 12p13.31 (LOD = 4.0 and 13q14.3 (Z score = 4.5, P = 6.6 × 10(-6. In conclusion, genetic ancestry has a significant association with type 2 diabetes above and beyond its association with non-genetic risk factors for type 2 diabetes in African Americans, but no single gene with a major effect is sufficient to explain a large portion of the observed population difference in risk of diabetes. There undoubtedly is a complex interplay among specific genetic loci and non-genetic factors, which may both be associated with overall admixture, leading to the observed ethnic differences in diabetes

  12. Admixture as a tool for finding linked genes and detecting that difference from allelic association between loci.

    Science.gov (United States)

    Chakraborty, R; Weiss, K M

    1988-12-01

    Admixture between genetically different populations may produce gametic association between gene loci as a function of the genetic difference between parental populations and the admixture rate. This association decays as a function of time since admixture and the recombination rate between the loci. Admixture between genetically long-separated human populations has been frequent in the centuries since the age of exploration and colonization, resulting in numerous hybrid descendant populations today, as in the Americas. This represents a natural experiment for genetic epidemiology and anthropology, in which to use polymorphic marker loci (e.g., restriction fragment length polymorphisms) and disequilibrium to infer a genetic basis for traits of interest. In this paper we show that substantial disequilibrium remains today under widely applicable situations, which can be detected without requiring inordinately close linkage between trait and marker loci. Very disparate parental allele frequencies produce large disequilibrium, but the sample size needed to detect such levels of disequilibrium can be large due to the skewed haplotype frequency distribution in the admixed population. Such situations, however, provide power to differentiate between disequilibrium due just to population mixing from that due to physical linkage of loci--i.e., to help map the genetic locus of the trait. A gradient of admixture levels between the same parental populations may be used to test genetic models by relating admixture to disequilibrium levels.

  13. Detection and characterization of stacking faults by light beam induced current mapping and scanning infrared microscopy in silicon

    Science.gov (United States)

    Vève-Fossati, C.; Martinuzzi, S.

    1998-08-01

    Non destructive techniques like scanning infrared microscopy and light beam induced current mapping are used to reveal the presence of stacking faults in heat treated Czochralski grown silicon wafers. In oxidized or contaminated samples, scanning infrared microscopy reveals that stacking faults grow around oxygen precipitates. This could be due to an aggregation of silicon self-interstitials emitted by the growing precipitates in the (111) plane. Light beam induced current maps show that the dislocations which surround the stacking faults are the main source of recombination centers, especially when they are decorated by a fast diffuser like copper. Des techniques non destructives telles que la microscopie infrarouge à balayage et la cartographie de photocourant induit par un spot lumineux ont été utilisées pour révéler la présence de fautes d'empilement après traitements thermiques, dans des plaquettes de silicium préparées par tirage Czochralski. Dans des échantillons oxydés ou contaminés, la microscopie infrarouge à balayage révèle des fautes d'empilement qui se développent autour des précipités d'oxygène. Cela peut être dû à la formation d'un agglomérat d'auto-interstitiels de silicium émis par la croissance des précipités dans les plans (111). Les cartographies de photocourant montrent que les dislocations qui entourent les fautes d'empilement sont la principale source de centres de recombinaison, et cela tout particulièrement quand ces fautes sont décorées par un diffuseur rapide tel que le cuivre.

  14. Genomic Scans of Zygotic Disequilibrium and Epistatic SNPs in HapMap Phase III Populations.

    Directory of Open Access Journals (Sweden)

    Xin-Sheng Hu

    Full Text Available Previous theory indicates that zygotic linkage disequilibrium (LD is more informative than gametic or composite digenic LD in revealing natural population history. Further, the difference between the composite digenic and maximum zygotic LDs can be used to detect epistatic selection for fitness. Here we corroborate the theory by investigating genome-wide zygotic LDs in HapMap phase III human populations. Results show that non-Africa populations have much more significant zygotic LDs than do Africa populations. Africa populations (ASW, LWK, MKK, and YRI possess more significant zygotic LDs for the double-homozygotes (DAABB than any other significant zygotic LDs (DAABb, DAaBB, and DAaBb, while non-Africa populations generally have more significant DAaBb's than any other significant zygotic LDs (DAABB, DAABb, and DAaBB. Average r-squares for any significant zygotic LDs increase generally in an order of populations YRI, MKK, CEU, CHB, LWK, JPT, CHD, TSI, GIH, ASW, and MEX. Average r-squares are greater for DAABB and DAaBb than for DAaBB and DAABb in each population. YRI and MKK can be separated from LWK and ASW in terms of the pattern of average r-squares. All population divergences in zygotic LDs can be interpreted with the model of Out of Africa for modern human origins. We have also detected 19735-95921 SNP pairs exhibiting strong signals of epistatic selection in different populations. Gene-gene interactions for some epistatic SNP pairs are evident from empirical findings, but many more epistatic SNP pairs await evidence. Common epistatic SNP pairs rarely exist among all populations, but exist in distinct regions (Africa, Europe, and East Asia, which helps to understand geographical genomic medicine.

  15. Black-backed woodpecker habitat suitability mapping using conifer snag basal area estimated from airborne laser scanning

    Science.gov (United States)

    Casas Planes, Á.; Garcia, M.; Siegel, R.; Koltunov, A.; Ramirez, C.; Ustin, S.

    2015-12-01

    Occupancy and habitat suitability models for snag-dependent wildlife species are commonly defined as a function of snag basal area. Although critical for predicting or assessing habitat suitability, spatially distributed estimates of snag basal area are not generally available across landscapes at spatial scales relevant for conservation planning. This study evaluates the use of airborne laser scanning (ALS) to 1) identify individual conifer snags and map their basal area across a recently burned forest, and 2) map habitat suitability for a wildlife species known to be dependent on snag basal area, specifically the black-backed woodpecker (Picoides arcticus). This study focuses on the Rim Fire, a megafire that took place in 2013 in the Sierra Nevada Mountains of California, creating large patches of medium- and high-severity burned forest. We use forest inventory plots, single-tree ALS-derived metrics and Gaussian processes classification and regression to identify conifer snags and estimate their stem diameter and basal area. Then, we use the results to map habitat suitability for the black-backed woodpecker using thresholds for conifer basal area from a previously published habitat suitability model. Local maxima detection and watershed segmentation algorithms resulted in 75% detection of trees with stem diameter larger than 30 cm. Snags are identified with an overall accuracy of 91.8 % and conifer snags are identified with an overall accuracy of 84.8 %. Finally, Gaussian process regression reliably estimated stem diameter (R2 = 0.8) using height and crown area. This work provides a fast and efficient methodology to characterize the extent of a burned forest at the tree level and a critical tool for early wildlife assessment in post-fire forest management and biodiversity conservation.

  16. Early hydration cement Effect of admixtures superplasticizers

    Directory of Open Access Journals (Sweden)

    Puertas, F.

    2001-06-01

    Full Text Available Early hydration of portland cement with superplasticizer admixtures of different nature has been studied. These admixtures were: one based on melamine synthetic, other based on vinyl copolymer and other based on polyacrylate copolymers. The dosage of the formers were constant (1% weigth of cement and for the third, the influence of admixture dosage was also evaluated, giving dosage values among 1-0.3%. The pastes obtained were studied by conduction calorimetry, XRD and FTIR. Also the apparent fluidity was determined by "Minislump" test. The main results obtained were: a superplasticizers admixtures used, regardless of their nature and for the polycarboxilate one the dosage, retard the silicate hydration (specially, alite phase, b The ettringite formation is affected by the nature of the admixture. cA relationship between the dosage of admixture based on polycarboxilates and the time at the acceleration has been established. A lineal relation (y = 11.03 + 16.05x was obtained. From these results is possible to know, in function of dosage admixture, the time when the masive hydration products and the setting times are produced. Also the total heat releases in these reactions is independent of the nature and dosage of admixture, saying that in all cases the reactions are the same.

    En el presente trabajo se ha estudiado la hidratación inicial de un cemento portland aditivado con superplastificantes de diferente naturaleza. Dichos aditivos fueron: uno basado en melaminas sintéticas, otro en copolímeros vinilicos y otro en policarboxilatos. La dosificación de los dos primeros se fijó constante en 1% en peso con relación al cemento, mientras que para el tercero se evaluó, también, la influencia de la dosificación, tomando proporciones desde el 1% hasta el 0,3%. Las pastas obtenidas se estudiaron por: calorimetría de conducción, DRX y FTIR. También se determinó la fluidez de la pasta a través del ensayo del "Minislump ". Los

  17. Spatial assessment of Argentinean genetic admixture with geographical information systems.

    Science.gov (United States)

    Diaz-Lacava, Amalia; Walier, Maja; Penacino, Gustavo; Wienker, Thomas F; Baur, Max P

    2011-08-01

    In recent years there has been much attention to Argentinean population stratification. We were interested in assessing population stratification from a geographical perspective and summarizing it in form of maps. We mapped the genetic admixture of the extant male population in central and northern Argentina on the basis of forensic Y-chromosomal haplotypes. We addressed the question which group of genetically similar individuals is predominant in this area. Haplotypes containing seven Y-chromosomal short tandem repeat polymorphisms (Y-STRs), also known as microsatellites - DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393 - were constructed for 145 individuals, recruited in 10 provinces. 97 distinct haplotypes were clustered into four clusters according to molecular distances. A genetic geostatistical analysis was conducted with the open-source geographical information system GRASS GIS. For each haplotype cluster, the according frequency was spatially interpolated over the total study area. Juxtaposing the interpolation surfaces, we screened point-wisely the maximal frequency as well as the label of the respective cluster. The screening results were combined in one summary map. We repeated this procedure for the second maximal frequencies. The resulting maps subdivide the study area into continuous regions comprising one predominant group of similar haplotypes. The first summary map divides the study area into three regions and the second summary map divides the area into four regions. The results of our analysis indicate that two groups of similar European haplotypes alternatively dominate the largest extension of the Argentinean territory. A third group, including South-American haplotypes, dominates the indigenous northwestern Argentinean area. The last group, including worldwide dispersed haplotypes, preponderates in frequency in second place in central Argentina. Our findings confirm a widespread European paternal ancestry, a substantial Amerindian

  18. Shrinkage and cracking behavior of high performance concretes containing chemical admixtures

    Institute of Scientific and Technical Information of China (English)

    亓萌; 李宗津; 马保国

    2002-01-01

    Modern concretes often incorporate several chemical admixtures to alter the properties of fresh or hardened concrete. In this work, the influences of three types of chemical admixtures, calcium nitrite inhibitor (CNI), retarder (D-17) and superplasticizer (W-19) on free shrinkage and restrained shrinkage cracking of high performance concrete were experimentally investigated. The test results showed that, with the same water to binder ratio (0.4), mixtures containing D-17 of 0.25 percent or higher ratio of W-19 (2.76 percent) all exhibited a reduction in free shrinkage and shrinkage cracking width. However, the incorporations of various ratios of CNI into mixtures led to an increase in free shrinkage and shrinkage cracking width as compared to control mixture. In order to study the influence of CNI, the microstructure of concrete mixture containing CNI were investigated by Mercury Intrusion Porosimetry as well as Scanning Electronic Microscopy(SEM) technique.

  19. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    NARCIS (Netherlands)

    Mendrik, A.M.; Vonken, E.J.; Ginneken, B. van; Jong, H.W. de; Riordan, A.; Seeters, T. van; Smit, E.J.; Viergever, M.A.; Prokop, M.

    2011-01-01

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiat

  20. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    NARCIS (Netherlands)

    A. Mendrik (Adrienne); E.J.P.A. Vonken; B.T.J. van Ginneken (Berbke); J.R. Riordan (John ); H.W.A.M. de Jong (Hugo); T. van Seeters (Tom); E.J. Smit (Ewoud); M.A. Viergever; M. Prokop (Mathias)

    2011-01-01

    textabstractCerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of

  1. Mapping tree health using airborne laser scans and hyperspectral imagery: a case study for a floodplain eucalypt forest

    Science.gov (United States)

    Shendryk, Iurii; Tulbure, Mirela; Broich, Mark; McGrath, Andrew; Alexandrov, Sergey; Keith, David

    2016-04-01

    Airborne laser scanning (ALS) and hyperspectral imaging (HSI) are two complementary remote sensing technologies that provide comprehensive structural and spectral characteristics of forests over large areas. In this study we developed two algorithms: one for individual tree delineation utilizing ALS and the other utilizing ALS and HSI to characterize health of delineated trees in a structurally complex floodplain eucalypt forest. We conducted experiments in the largest eucalypt, river red gum forest in the world, located in the south-east of Australia that experienced severe dieback over the past six decades. For detection of individual trees from ALS we developed a novel bottom-up approach based on Euclidean distance clustering to detect tree trunks and random walks segmentation to further delineate tree crowns. Overall, our algorithm was able to detect 67% of tree trunks with diameter larger than 13 cm. We assessed the accuracy of tree delineations in terms of crown height and width, with correct delineation of 68% of tree crowns. The increase in ALS point density from ~12 to ~24 points/m2 resulted in tree trunk detection and crown delineation increase of 11% and 13%, respectively. Trees with incorrectly delineated crowns were generally attributed to areas with high tree density along water courses. The accurate delineation of trees allowed us to classify the health of this forest using machine learning and field-measured tree crown dieback and transparency ratios, which were good predictors of tree health in this forest. ALS and HSI derived indices were used as predictor variables to train and test object-oriented random forest classifier. Returned pulse width, intensity and density related ALS indices were the most important predictors in the tree health classifications. At the forest level in terms of tree crown dieback, 77% of trees were classified as healthy, 14% as declining and 9% as dying or dead with 81% mapping accuracy. Similarly, in terms of tree

  2. Mapping microclimate pH distribution inside protein-encapsulated PLGA microspheres using confocal laser scanning microscopy.

    Science.gov (United States)

    Liu, Yajun; Schwendeman, Steven P

    2012-05-01

    The pH in the aqueous pores of poly(lactide-co-glycolide) (PLGA) matrix, also referred to as microclimate pH (μpH), is often uncontrolled, ranging from highly acidic to neutral pH range. The μpH distribution inside protein-encapsulated PLGA microspheres was quantitatively evaluated using confocal laser scanning microscopy. The fluorescent response of Lysosensor yellow/blue dextran used to map μpH in PLGA was influenced by the presence of encapsulated protein. The nonprotonated form of pyridyl group on the fluorescence probe at neutral pH was responsible for the interference, which was dependent on the type and concentration of protein. A method for correction of this interference based on estimating protein concentration inside the microspheres was established and validated. After correction of the influence, the μpH distribution kinetics inside microspheres was evaluated for different PLGA 50/50 microsphere formulations under physiological conditions for 4 weeks. Generally, the μpH acidity increased with the progression of incubation time. The coincorporation of poorly soluble base, magnesium carbonate, in the microspheres prolonged the appearance of detectable acidity for up to 3 weeks. Co-addition of an acetate buffer was able to control the μpH over a slightly acidic range (around pH 4.7) after two week incubation. Microspheres prepared from a lower polymer concentration exhibited a higher μpH, likely owing to reduced diffusional resistance to acidic degradation products. The stability of protein was enhanced by addition of MgCO(3), acetate buffer, or by reduced polymer concentration in the preparation, as evidenced by more soluble protein recovered after incubation. Hence, the μpH imaging technique developed can be employed in the future for optimization of formulation strategies for controlling μpH and stabilizing encapsulated proteins. PMID:22428586

  3. Informativeness of the CODIS STR loci for admixture analysis.

    Science.gov (United States)

    Barnholtz-Sloan, Jill S; Pfaff, Carrie L; Chakraborty, Ranajit; Long, Jeffrey C

    2005-11-01

    Population admixture (or ancestry) is used as an approach to gene discovery in complex diseases, particularly when the disease prevalence varies widely across geographic populations. Admixture analysis could be useful for forensics because an indication of a perpetrator's ancestry would narrow the pool of suspects for a particular crime. The purpose of this study was to use Fisher's information to identify informative sets of markers for admixture analysis. Using published founding population allele frequencies we test three marker sets for efficacy for estimating admixture: the FBI CODIS Core STR loci, the HGDP-CEPH Human Genome Diversity Cell Line Panel and the set of 39 ancestry informative SNPS from the Shriver lab at Pennsylvania State University. We conclude that the FBI CODIS Core STR set is valid for admixture analysis, but not the most precise. We recommend using a combination of the most informative markers from the HGDP-CEPH and Shriver loci sets.

  4. 视线鼠标在电子地图浏览中的应用%The application of sight mouse in map scanning

    Institute of Scientific and Technical Information of China (English)

    吕佩育; 张春森; 王延亮; 吕静凡

    2012-01-01

    电子地图越来越多地进入人们的生活,但肢体残疾人士很难使用鼠标浏览电子地图.另外,公共场所用触摸屏操作电子地图存在卫生问题.因此,使用非接触的人机交互方式浏览地图成为需要解决的问题.近年来,人机交互中视线跟踪技术的发展,为问题的解决提供了可能.通过用视线鼠标浏览电子地图的实验,设计基于视线鼠标的地图浏览工具,成功实现非接触方式浏览电子地图的目标.%Electronic map comes into our life gradually. However, it is difficult for body disabled people to browse electronic map using mouse. In addition, there is a sanitation problem on using electronic map with touch screen in public. Therefore, it becomes a problem to browse map using human-computer interaction with non-contact way. In recent years, it is possible to solve the problem with the development of sight tracking technology in human-computer interaction. The author performs an experiment of electronic map scanning with sight mouse, and designs a map scanning tool based on sight mouse. Finally, the author realizes the goal of browsing electronic map with non-contact way.

  5. Multiway admixture deconvolution using phased or unphased ancestral panels.

    Science.gov (United States)

    Churchhouse, Claire; Marchini, Jonathan

    2013-01-01

    We describe a novel method for inferring the local ancestry of admixed individuals from dense genome-wide single nucleotide polymorphism data. The method, called MULTIMIX, allows multiple source populations, models population linkage disequilibrium between markers and is applicable to datasets in which the sample and source populations are either phased or unphased. The model is based upon a hidden Markov model of switches in ancestry between consecutive windows of loci. We model the observed haplotypes within each window using a multivariate normal distribution with parameters estimated from the ancestral panels. We present three methods to fit the model-Markov chain Monte Carlo sampling, the Expectation Maximization algorithm, and a Classification Expectation Maximization algorithm. The performance of our method on individuals simulated to be admixed with European and West African ancestry shows it to be comparable to HAPMIX, the ancestry calls of the two methods agreeing at 99.26% of loci across the three parameter groups. In addition to it being faster than HAPMIX, it is also found to perform well over a range of extent of admixture in a simulation involving three ancestral populations. In an analysis of real data, we estimate the contribution of European, West African and Native American ancestry to each locus in the Mexican samples of HapMap, giving estimates of ancestral proportions that are consistent with those previously reported. PMID:23136122

  6. Behavior of passive admixture in a vortical hydrodynamic field

    Directory of Open Access Journals (Sweden)

    R.O.Bobrov

    2006-01-01

    Full Text Available The motion of passive admixture of spherical particles in the stationary hydrodynamic field of a swirling flow is studied. A spherical particle of a given mass in the hydrodynamic field of a swirling flow is located on a certain circular orbit, where the centrifugal force is compensated by the radial drag force due to the sink. This leads to the separation of the host fluid and admixture. A theory of Brownian motion of admixture in dilute solutions with a non-uniform flow is constructed.

  7. SU-E-J-113: Effects of Deformable Registration On First-Order Texture Maps Calculated From Thoracic Lung CT Scans

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C; Cunliffe, A; Al-Hallaq, H; Armato, S [The University of Chicago, Chicago, IL (United States)

    2015-06-15

    Purpose: To determine the stability of eight first-order texture features following the deformable registration of serial computed tomography (CT) scans. Methods: CT scans at two different time points from 10 patients deemed to have no lung abnormalities by a radiologist were collected. Following lung segmentation using an in-house program, texture maps were calculated from 32×32-pixel regions of interest centered at every pixel in the lungs. The texture feature value of the ROI was assigned to the center pixel of the ROI in the corresponding location of the texture map. Pixels in the square ROI not contained within the segmented lung were not included in the calculation. To quantify the agreement between ROI texture features in corresponding pixels of the baseline and follow-up texture maps, the Fraunhofer MEVIS EMPIRE10 deformable registration algorithm was used to register the baseline and follow-up scans. Bland-Altman analysis was used to compare registered scan pairs by computing normalized bias (nBias), defined as the feature value change normalized to the mean feature value, and normalized range of agreement (nRoA), defined as the range spanned by the 95% limits of agreement normalized to the mean feature value. Results: Each patient’s scans contained between 6.8–15.4 million ROIs. All of the first-order features investigated were found to have an nBias value less than 0.04% and an nRoA less than 19%, indicating that the variability introduced by deformable registration was low. Conclusion: The eight first-order features investigated were found to be registration stable. Changes in CT texture maps could allow for temporal-spatial evaluation of the evolution of lung abnormalities relating to a variety of diseases on a patient-by-patient basis. SGA and HA receives royalties and licensing fees through the University of Chicago for computer-aided diagnosis technology. Research reported in this publication was supported by the National Institute Of General

  8. SU-E-J-113: Effects of Deformable Registration On First-Order Texture Maps Calculated From Thoracic Lung CT Scans

    International Nuclear Information System (INIS)

    Purpose: To determine the stability of eight first-order texture features following the deformable registration of serial computed tomography (CT) scans. Methods: CT scans at two different time points from 10 patients deemed to have no lung abnormalities by a radiologist were collected. Following lung segmentation using an in-house program, texture maps were calculated from 32×32-pixel regions of interest centered at every pixel in the lungs. The texture feature value of the ROI was assigned to the center pixel of the ROI in the corresponding location of the texture map. Pixels in the square ROI not contained within the segmented lung were not included in the calculation. To quantify the agreement between ROI texture features in corresponding pixels of the baseline and follow-up texture maps, the Fraunhofer MEVIS EMPIRE10 deformable registration algorithm was used to register the baseline and follow-up scans. Bland-Altman analysis was used to compare registered scan pairs by computing normalized bias (nBias), defined as the feature value change normalized to the mean feature value, and normalized range of agreement (nRoA), defined as the range spanned by the 95% limits of agreement normalized to the mean feature value. Results: Each patient’s scans contained between 6.8–15.4 million ROIs. All of the first-order features investigated were found to have an nBias value less than 0.04% and an nRoA less than 19%, indicating that the variability introduced by deformable registration was low. Conclusion: The eight first-order features investigated were found to be registration stable. Changes in CT texture maps could allow for temporal-spatial evaluation of the evolution of lung abnormalities relating to a variety of diseases on a patient-by-patient basis. SGA and HA receives royalties and licensing fees through the University of Chicago for computer-aided diagnosis technology. Research reported in this publication was supported by the National Institute Of General

  9. Learning with Admixture: Modeling, Optimization, and Applications in Population Genetics

    DEFF Research Database (Denmark)

    Cheng, Jade Yu

    2016-01-01

    with the big data era. In this PhD dissertation, I present my work on methods and tools developed for two projects, Admixture CoalHMM and Ohana, both of which have been designed to study historical admixture and its influence on population evolution. In Admixture CoalHMM, I make use of full genomic sequences...... geneticists strive to establish working solutions to extract information from massive volumes of biological data. The steep increase in the quantity and quality of genomic data during the past decades provides a unique opportunity but also calls for new and improved algorithms and software to cope...... from a few individuals to perform demographic inference. In Ohana, I use site-independent genomic data from many individuals to analyze individual admixture, to infer population trees, and to identify selection signals. The development of CoalHMM at the Bioinformatics Research Centre at Aarhus...

  10. Development, Calibration and Evaluation of a Portable and Direct Georeferenced Laser Scanning System for Kinematic 3D Mapping

    Science.gov (United States)

    Heinz, Erik; Eling, Christian; Wieland, Markus; Klingbeil, Lasse; Kuhlmann, Heiner

    2015-12-01

    In recent years, kinematic laser scanning has become increasingly popular because it offers many benefits compared to static laser scanning. The advantages include both saving of time in the georeferencing and a more favorable scanning geometry. Often mobile laser scanning systems are installed on wheeled platforms, which may not reach all parts of the object. Hence, there is an interest in the development of portable systems, which remain operational even in inaccessible areas. The development of such a portable laser scanning system is presented in this paper. It consists of a lightweight direct georeferencing unit for the position and attitude determination and a small low-cost 2D laser scanner. This setup provides advantages over existing portable systems that employ heavy and expensive 3D laser scanners in a profiling mode. A special emphasis is placed on the system calibration, i. e. the determination of the transformation between the coordinate frames of the direct georeferencing unit and the 2D laser scanner. To this end, a calibration field is used, which consists of differently orientated georeferenced planar surfaces, leading to estimates for the lever arms and boresight angles with an accuracy of mm and one-tenth of a degree. Finally, point clouds of the mobile laser scanning system are compared with georeferenced point clouds of a high-precision 3D laser scanner. Accordingly, the accuracy of the system is in the order of cm to dm. This is in good agreement with the expected accuracy, which has been derived from the error propagation of previously estimated variance components.

  11. Using side-scan sonar to characterize and map physical habitat and anthropogenic underwater features in the St. Louis River.

    Science.gov (United States)

    Characterizing underwater habitat and other features is difficult and costly, especially in the large St. Louis River Estuary. We are using side-scan sonar (SSS), first developed in the 1960s to remotely sense underwater habitat features from reflected acoustic signals (backscatt...

  12. Optimized AIR and investigational MOLLI cardiac T1 mapping pulse sequences produce similar intra-scan repeatability in patients at 3T.

    Science.gov (United States)

    Hong, KyungPyo; Collins, Jeremy; Lee, Daniel C; Wilcox, Jane E; Markl, Michael; Carr, James; Kim, Daniel

    2016-10-01

    This study was conducted to improve the precision of arrhythmia-insensitive rapid (AIR) cardiac T1 mapping through pulse sequence optimization and then evaluate the intra-scan repeatability in patients at 3T against investigational modified Look-Locker inversion recovery (MOLLI) T1 mapping. In the first development phase (five human subjects), we implemented and tested centric-pair k-space ordering to suppress image artifacts associated with eddy currents. In the second development phase (15 human subjects), we determined optimal flip angles to reduce the measurement variation in T1 maps. In the validation phase (35 patients), we compared the intra-scan repeatability between investigational MOLLI and optimized AIR. In 23 cardiac planes, conventional centric k-space ordering (3.7%) produced significantly (p variation while producing results that are not significantly different from those produced with the previously used flip angle of 35° (p > 0.89, intra-class correlation coefficient ≥ 0.95 for all four measurement types). Compared with investigational MOLLI (coefficient of repeatability, CR = 40.0, 77.2, 26.5, and 25.9 ms for native myocardial, native blood, post-contrast myocardial, and post-contrast blood T1 , and 2.0% for extracellular volume (ECV) measurements, respectively), optimized AIR (CR = 54.3, 89.7, 30.5, and 14.7 ms for native myocardial, native blood, post-contrast myocardial, and post-contrast blood T1 , and 1.6% for ECV measurements, respectively) produced similar absolute intra-scan repeatability in all 35 patients in the validation phase. High repeatability is critically important for longitudinal studies, where the goal is to monitor physiologic/pathologic changes, not measurement variation. Optimized AIR cardiac T1 mapping is likely to yield high scan-retest repeatability for pre-clinical and clinical applications. PMID:27593977

  13. Mapping an on-chip terahertz antenna by a scanning near-field probe and a fixed field-effect transistor

    International Nuclear Information System (INIS)

    In the terahertz (THz) regime, the active region for a solid-state detector usually needs to be implemented accurately in the near-field region of an on-chip antenna. Mapping of the near-field strength could allow for rapid verification and optimization of new antenna/detector designs. Here, we report a proof-of-concept experiment in which the field mapping is realized by a scanning metallic probe and a fixed AlGaN/GaN field-effect transistor. Experiment results agree well with the electromagnetic-wave simulations. The results also suggest a field-effect THz detector combined with a probe tip could serve as a high sensitivity THz near-field sensor. (paper)

  14. Mapping an on-chip terahertz antenna by a scanning near-field probe and a fixed field-effect transistor

    Institute of Scientific and Technical Information of China (English)

    吕利; 孙建东; RogerA.Lewis; 孙云飞; 吴东岷; 蔡勇; 秦华

    2015-01-01

    In the terahertz (THz) regime, the active region for a solid-state detector usually needs to be implemented accurately in the near-field region of an on-chip antenna. Mapping of the near-field strength could allow for rapid verification and optimization of new antenna/detector designs. Here, we report a proof-of-concept experiment in which the field mapping is realized by a scanning metallic probe and a fixed AlGaN/GaN field-effect transistor. Experiment results agree well with the electromagnetic-wave simulations. The results also suggest a field-effect THz detector combined with a probe tip could serve as a high sensitivity THz near-field sensor.

  15. Use of pentapeptide-insertion scanning mutagenesis for functional mapping of the plum pox virus helper component proteinase suppressor of gene silencing.

    Science.gov (United States)

    Varrelmann, Mark; Maiss, Edgar; Pilot, Ruth; Palkovics, Laszlo

    2007-03-01

    Helper component proteinase (HC-Pro) of Plum pox virus is a multifunctional potyvirus protein that has been examined intensively. In addition to its involvement in aphid transmission, genome amplification and long-distance movement, it is also one of the better-studied plant virus suppressors of RNA silencing. The first systematic analysis using pentapeptide-insertion scanning mutagenesis of the silencing suppression function of a potyvirus HC-Pro is presented here. Sixty-three in-frame insertion mutants, each containing five extra amino acids inserted randomly within the HC-Pro protein, were analysed for their ability to suppress transgene-induced RNA silencing using Agrobacterium infiltration in transgenic Nicotiana benthamiana plants expressing green fluorescent protein. A functional map was obtained, consisting of clearly defined regions with different classes of silencing-suppression activity (wild-type, restricted and disabled). This map confirmed that the N-terminal part of the protein, which is indispensable for aphid transmission, is dispensable for silencing suppression and supports the involvement of the central region in silencing suppression, in addition to its role in maintenance of genome amplification and synergism with other viruses. Moreover, evidence is provided that the C-terminal part of the protein, previously known to be necessary mainly for proteolytic activity, also participates in silencing suppression. Pentapeptide-insertion scanning mutagenesis has been shown to be a fast and powerful tool to functionally characterize plant virus proteins. PMID:17325375

  16. 3D mapping of geological contacts by coupling Aerial Laser Scanning, Gigapixel photography and open access pictures

    Science.gov (United States)

    Nguyen, Liliane; Guerin, Antoine; Abellán, Antonio; Carrea, Dario; Derron, Marc-Henri; Jaboyedoff, Michel

    2015-04-01

    Multiple sources of geological data exist nowadays, most of them are in 2D (e.g. geological maps, geological panoramic sketch), and only a few are in 3D (e.g. block diagram). One of the current challenges in geological mapping consists not only in providing a more consistent 3D data, but also in pursuing a gathering and a harmonisation of the geological information in order to obtain a more consistent interpretations of the 3D geological models. New remote sensing techniques have significantly improved the representation of three-dimensional surfaces during the last decade, especially for steep and inaccessible rockcliffs. Therefore, we present an exploratory study aiming to find a reliable method for carrying out a three-dimensional mapping of geological contacts using a High Resolution Digital Elevation Model (HRDEM) with a 1 meter cell size. To this end, we selected the "Scex Rouge Mountain" as pilot study area. This outcrop, which is located in the Diablerets Massif (Vaud, Swiss Alps), has the particularity to present very distinguishable folded geological boundaries on its Southern face. The Southern slope belongs to the Wildhorn nappe, which is mainly composed of sedimentary rocks. The top-layer is composed of siliceous limestones, the well-visible fold layer is the "Pygurus layer" and consist of sandy limestone. Finally the bottom-layer includes marly schist and clayey limestones. At first, different sources of information has been draped on the HRDEM of the Scex Rouge Mountain, including not only classical geological maps (1:25 000) but also different sources of imagery (e.g. gigapixel panoramas, open access images, etc.). In a second step, several three-dimensional polylines have been drawn following the geological limit on each drapped HRDEM. Then we investigated the accuracy of 2D classical geological maps by comparing these geological limits with the drawn 3D polylines. Furthermore, in order to evaluate the accuracy of the method, a ground truth needs

  17. Mutation Scanning Using MUT-MAP, a High-Throughput, Microfluidic Chip-Based, Multi-Analyte Panel

    OpenAIRE

    Patel, Rajesh; Tsan, Alison; Tam, Rachel; Desai, Rupal; Schoenbrunner, Nancy; Myers, Thomas W.; Bauer, Keith; Smith, Edward; Raja, Rajiv

    2012-01-01

    Targeted anticancer therapies rely on the identification of patient subgroups most likely to respond to treatment. Predictive biomarkers play a key role in patient selection, while diagnostic and prognostic biomarkers expand our understanding of tumor biology, suggest treatment combinations, and facilitate discovery of novel drug targets. We have developed a high-throughput microfluidics method for mutation detection (MUT-MAP, mutation multi-analyte panel) based on TaqMan or allele-specific P...

  18. Biodiversity Mapping via Natura 2000 Conservation Status and Ebv Assessment Using Airborne Laser Scanning in Alkali Grasslands

    Science.gov (United States)

    Zlinszky, A.; Deák, B.; Kania, A.; Schroiff, A.; Pfeifer, N.

    2016-06-01

    Biodiversity is an ecological concept, which essentially involves a complex sum of several indicators. One widely accepted such set of indicators is prescribed for habitat conservation status assessment within Natura 2000, a continental-scale conservation programme of the European Union. Essential Biodiversity Variables are a set of indicators designed to be relevant for biodiversity and suitable for global-scale operational monitoring. Here we revisit a study of Natura 2000 conservation status mapping via airbone LIDAR that develops individual remote sensing-derived proxies for every parameter required by the Natura 2000 manual, from the perspective of developing regional-scale Essential Biodiversity Variables. Based on leaf-on and leaf-off point clouds (10 pt/m2) collected in an alkali grassland area, a set of data products were calculated at 0.5 ×0.5 m resolution. These represent various aspects of radiometric and geometric texture. A Random Forest machine learning classifier was developed to create fuzzy vegetation maps of classes of interest based on these data products. In the next step, either classification results or LIDAR data products were selected as proxies for individual Natura 2000 conservation status variables, and fine-tuned based on field references. These proxies showed adequate performance and were summarized to deliver Natura 2000 conservation status with 80% overall accuracy compared to field references. This study draws attention to the potential of LIDAR for regional-scale Essential Biodiversity variables, and also holds implications for global-scale mapping. These are (i) the use of sensor data products together with habitat-level classification, (ii) the utility of seasonal data, including for non-seasonal variables such as grassland canopy structure, and (iii) the potential of fuzzy mapping-derived class probabilities as proxies for species presence and absence.

  19. BIODIVERSITY MAPPING VIA NATURA 2000 CONSERVATION STATUS AND EBV ASSESSMENT USING AIRBORNE LASER SCANNING IN ALKALI GRASSLANDS

    Directory of Open Access Journals (Sweden)

    A. Zlinszky

    2016-06-01

    Full Text Available Biodiversity is an ecological concept, which essentially involves a complex sum of several indicators. One widely accepted such set of indicators is prescribed for habitat conservation status assessment within Natura 2000, a continental-scale conservation programme of the European Union. Essential Biodiversity Variables are a set of indicators designed to be relevant for biodiversity and suitable for global-scale operational monitoring. Here we revisit a study of Natura 2000 conservation status mapping via airbone LIDAR that develops individual remote sensing-derived proxies for every parameter required by the Natura 2000 manual, from the perspective of developing regional-scale Essential Biodiversity Variables. Based on leaf-on and leaf-off point clouds (10 pt/m2 collected in an alkali grassland area, a set of data products were calculated at 0.5 ×0.5 m resolution. These represent various aspects of radiometric and geometric texture. A Random Forest machine learning classifier was developed to create fuzzy vegetation maps of classes of interest based on these data products. In the next step, either classification results or LIDAR data products were selected as proxies for individual Natura 2000 conservation status variables, and fine-tuned based on field references. These proxies showed adequate performance and were summarized to deliver Natura 2000 conservation status with 80% overall accuracy compared to field references. This study draws attention to the potential of LIDAR for regional-scale Essential Biodiversity variables, and also holds implications for global-scale mapping. These are (i the use of sensor data products together with habitat-level classification, (ii the utility of seasonal data, including for non-seasonal variables such as grassland canopy structure, and (iii the potential of fuzzy mapping-derived class probabilities as proxies for species presence and absence.

  20. Worldwide patterns of ancestry, divergence, and admixture in domesticated cattle.

    Directory of Open Access Journals (Sweden)

    Jared E Decker

    2014-03-01

    Full Text Available The domestication and development of cattle has considerably impacted human societies, but the histories of cattle breeds and populations have been poorly understood especially for African, Asian, and American breeds. Using genotypes from 43,043 autosomal single nucleotide polymorphism markers scored in 1,543 animals, we evaluate the population structure of 134 domesticated bovid breeds. Regardless of the analytical method or sample subset, the three major groups of Asian indicine, Eurasian taurine, and African taurine were consistently observed. Patterns of geographic dispersal resulting from co-migration with humans and exportation are recognizable in phylogenetic networks. All analytical methods reveal patterns of hybridization which occurred after divergence. Using 19 breeds, we map the cline of indicine introgression into Africa. We infer that African taurine possess a large portion of wild African auroch ancestry, causing their divergence from Eurasian taurine. We detect exportation patterns in Asia and identify a cline of Eurasian taurine/indicine hybridization in Asia. We also identify the influence of species other than Bos taurus taurus and B. t. indicus in the formation of Asian breeds. We detect the pronounced influence of Shorthorn cattle in the formation of European breeds. Iberian and Italian cattle possess introgression from African taurine. American Criollo cattle originate from Iberia, and not directly from Africa with African ancestry inherited via Iberian ancestors. Indicine introgression into American cattle occurred in the Americas, and not Europe. We argue that cattle migration, movement and trading followed by admixture have been important forces in shaping modern bovine genomic variation.

  1. Variation in genetic admixture and population structure among Latinos: the Los Angeles Latino eye study (LALES

    Directory of Open Access Journals (Sweden)

    Le Marchand Loic

    2009-11-01

    Full Text Available Abstract Background Population structure and admixture have strong confounding effects on genetic association studies. Discordant frequencies for age-related macular degeneration (AMD risk alleles and for AMD incidence and prevalence rates are reported across different ethnic groups. We examined the genomic ancestry characterizing 538 Latinos drawn from the Los Angeles Latino Eye Study [LALES] as part of an ongoing AMD-association study. To help assess the degree of Native American ancestry inherited by Latino populations we sampled 25 Mayans and 5 Mexican Indians collected through Coriell's Institute. Levels of European, Asian, and African descent in Latinos were inferred through the USC Multiethnic Panel (USC MEP, formed from a sample from the Multiethnic Cohort (MEC study, the Yoruba African samples from HapMap II, the Singapore Chinese Health Study, and a prospective cohort from Shanghai, China. A total of 233 ancestry informative markers were genotyped for 538 LALES Latinos, 30 Native Americans, and 355 USC MEP individuals (African Americans, Japanese, Chinese, European Americans, Latinos, and Native Hawaiians. Sensitivity of ancestry estimates to relative sample size was considered. Results We detected strong evidence for recent population admixture in LALES Latinos. Gradients of increasing Native American background and of correspondingly decreasing European ancestry were observed as a function of birth origin from North to South. The strongest excess of homozygosity, a reflection of recent population admixture, was observed in non-US born Latinos that recently populated the US. A set of 42 SNPs especially informative for distinguishing between Native Americans and Europeans were identified. Conclusion These findings reflect the historic migration patterns of Native Americans and suggest that while the 'Latino' label is used to categorize the entire population, there exists a strong degree of heterogeneity within that population, and that

  2. Scanning micro-Hall probe mapping of magnetic flux distributions and current densities in YBa{sub 2}Cu{sub 3}O{sub 7}

    Energy Technology Data Exchange (ETDEWEB)

    Xing, W.; Heinrich, B. [Simon Fraser Univ., British Columbia (Canada); Zhou, H. [CTF Systems, Inc., British Columbia (Canada)] [and others

    1994-12-31

    Mapping of the magnetic flux density B{sub z} (perpendicular to the film plane) for a YBa{sub 2}Cu{sub 3}O{sub 7} thin-film sample was carried out using a scanning micro-Hall probe. The sheet magnetization and sheet current densities were calculated from the B{sub z} distributions. From the known sheet magnetization, the tangential (B{sub x,y}) and normal components of the flux density B were calculated in the vicinity of the film. It was found that the sheet current density was mostly determined by 2B{sub x,y}/d, where d is the film thickness. The evolution of flux penetration as a function of applied field will be shown.

  3. Ultrasonic attenuation maps of liver based on a conventional B-scan and an amplitude loss technique.

    Science.gov (United States)

    Shmulewitz, A; Heyman, Z; Walach, E; Ramot, B; Itzchak, Y

    1990-10-01

    The authors present a novel ultrasonic amplitude loss technique, using image processing techniques and designed for computation of local attenuation estimates. Three different estimation approaches were evaluated: the extended Prony, the maximum likelihood, and the least squares approaches. The latter two approaches were found to result in a much higher estimation error than that observed for the Prony method. The attenuation values in the normal population (49 subjects) were 0.44 +/- 0.03 dB/MHz/cm. Three hundred sixty-seven liver scans from 266 patients were evaluated. Hodgkin's lymphoma patients with liver involvement had attenuation values of 0.22 +/- 0.07 dB/MHz/cm. Low attenuation values also were observed for four patients with viral hepatitis (0.31 +/- 0.08 dB/MHz/cm). The detectability of other disease states was not increased by these global attenuation estimates; however, the results demonstrate possible potential uses for the proposed technique for the diagnosis of diffuse liver disease.

  4. Research and manufacture about high-activity small admixture in sprayed concrete

    Energy Technology Data Exchange (ETDEWEB)

    Fan, W.; Zhang, Z.; Zheng, Y. [Jiaozuo Institute of Technology, Jiaozuo (China)

    2000-04-01

    Two types of high-activity small admixture are researched and produced by using industrial wastes: (1) F-type high-activity small admixture; (2) K-type high-activity small admixture. If these high-activity small admixtures were used to replace 30 percent of cement, the strength of the sprayed concrete may be enhanced by about 20 percent. 1 ref., 7 tabs.

  5. Detection of prostate cancer by integration of line-scan diffusion, T2-mapping and T2-weighted magnetic resonance imaging; a multichannel statistical classifier

    International Nuclear Information System (INIS)

    A multichannel statistical classifier for detecting prostate cancer was developed and validated by combining information from three different magnetic resonance (MR) methodologies: T2-weighted, T2-mapping, and line scan diffusion imaging (LSDI). From these MR sequences, four different sets of image intensities were obtained: T2-weighted (T2W) from T2-weighted imaging, Apparent Diffusion Coefficient (ADC) from LSDI, and proton density (PD) and T2 (T2 Map) from T2-mapping imaging. Manually segmented tumor labels from a radiologist, which were validated by biopsy results, served as tumor ''ground truth.'' Textural features were extracted from the images using co-occurrence matrix (CM) and discrete cosine transform (DCT). Anatomical location of voxels was described by a cylindrical coordinate system. A statistical jack-knife approach was used to evaluate our classifiers. Single-channel maximum likelihood (ML) classifiers were based on 1 of the 4 basic image intensities. Our multichannel classifiers: support vector machine (SVM) and Fisher linear discriminant (FLD), utilized five different sets of derived features. Each classifier generated a summary statistical map that indicated tumor likelihood in the peripheral zone (PZ) of the prostate gland. To assess classifier accuracy, the average areas under the receiver operator characteristic (ROC) curves over all subjects were compared. Our best FLD classifier achieved an average ROC area of 0.839(±0.064), and our best SVM classifier achieved an average ROC area of 0.761(±0.043). The T2W ML classifier, our best single-channel classifier, only achieved an average ROC area of 0.599(±0.146). Compared to the best single-channel ML classifier, our best multichannel FLD and SVM classifiers have statistically superior ROC performance (P=0.0003 and 0.0017, respectively) from pairwise two-sided t-test. By integrating the information from multiple images and capturing the textural and anatomical features in tumor areas, summary

  6. Detection of prostate cancer by integration of line-scan diffusion, T2-mapping and T2-weighted magnetic resonance imaging; a multichannel statistical classifier.

    Science.gov (United States)

    Chan, Ian; Wells, William; Mulkern, Robert V; Haker, Steven; Zhang, Jianqing; Zou, Kelly H; Maier, Stephan E; Tempany, Clare M C

    2003-09-01

    A multichannel statistical classifier for detecting prostate cancer was developed and validated by combining information from three different magnetic resonance (MR) methodologies: T2-weighted, T2-mapping, and line scan diffusion imaging (LSDI). From these MR sequences, four different sets of image intensities were obtained: T2-weighted (T2W) from T2-weighted imaging, Apparent Diffusion Coefficient (ADC) from LSDI, and proton density (PD) and T2 (T2 Map) from T2-mapping imaging. Manually segmented tumor labels from a radiologist, which were validated by biopsy results, served as tumor "ground truth." Textural features were extracted from the images using co-occurrence matrix (CM) and discrete cosine transform (DCT). Anatomical location of voxels was described by a cylindrical coordinate system. A statistical jack-knife approach was used to evaluate our classifiers. Single-channel maximum likelihood (ML) classifiers were based on 1 of the 4 basic image intensities. Our multichannel classifiers: support vector machine (SVM) and Fisher linear discriminant (FLD), utilized five different sets of derived features. Each classifier generated a summary statistical map that indicated tumor likelihood in the peripheral zone (PZ) of the prostate gland. To assess classifier accuracy, the average areas under the receiver operator characteristic (ROC) curves over all subjects were compared. Our best FLD classifier achieved an average ROC area of 0.839(+/-0.064), and our best SVM classifier achieved an average ROC area of 0.761(+/-0.043). The T2W ML classifier, our best single-channel classifier, only achieved an average ROC area of 0.599(+/-0.146). Compared to the best single-channel ML classifier, our best multichannel FLD and SVM classifiers have statistically superior ROC performance (P=0.0003 and 0.0017, respectively) from pairwise two-sided t-test. By integrating the information from multiple images and capturing the textural and anatomical features in tumor areas, summary

  7. Mapping asthma-associated variants in admixed populations

    OpenAIRE

    Mersha, Tesfaye B.

    2015-01-01

    Admixed populations arise when two or more previously isolated populations interbreed. Mapping asthma susceptibility loci in an admixed population using admixture mapping (AM) involves screening the genome of individuals of mixed ancestry for chromosomal regions that have a higher frequency of alleles from a parental population with higher asthma risk as compared with parental population with lower asthma risk. AM takes advantage of the admixture created in populations of mixed ancestry to id...

  8. Mapping asthma-associated variants in admixed populations

    OpenAIRE

    Mersha, Tesfaye B.

    2015-01-01

    Admixed populations arise when two or more previously isolated populations start interbreeding. Mapping asthma susceptibility loci in an admixed population using admixture mapping (AM) involves screening the genome of individuals of mixed ancestry for chromosomal regions that have a higher frequency of alleles compared to the parental population with higher asthma risk. AM takes advantage of the admixture created in populations of mixed ancestry by searching for association between the ancest...

  9. North African populations carry the signature of admixture with Neandertals

    DEFF Research Database (Denmark)

    Sánchez-Quinto, Federico; Botigué, Laura R; Civit, Sergi;

    2012-01-01

    One of the main findings derived from the analysis of the Neandertal genome was the evidence for admixture between Neandertals and non-African modern humans. An alternative scenario is that the ancestral population of non-Africans was closer to Neandertals than to Africans because of ancient popu...

  10. North African populations carry the signature of admixture with Neandertals.

    Directory of Open Access Journals (Sweden)

    Federico Sánchez-Quinto

    Full Text Available One of the main findings derived from the analysis of the Neandertal genome was the evidence for admixture between Neandertals and non-African modern humans. An alternative scenario is that the ancestral population of non-Africans was closer to Neandertals than to Africans because of ancient population substructure. Thus, the study of North African populations is crucial for testing both hypotheses. We analyzed a total of 780,000 SNPs in 125 individuals representing seven different North African locations and searched for their ancestral/derived state in comparison to different human populations and Neandertals. We found that North African populations have a significant excess of derived alleles shared with Neandertals, when compared to sub-Saharan Africans. This excess is similar to that found in non-African humans, a fact that can be interpreted as a sign of Neandertal admixture. Furthermore, the Neandertal's genetic signal is higher in populations with a local, pre-Neolithic North African ancestry. Therefore, the detected ancient admixture is not due to recent Near Eastern or European migrations. Sub-Saharan populations are the only ones not affected by the admixture event with Neandertals.

  11. Mutation scanning using MUT-MAP, a high-throughput, microfluidic chip-based, multi-analyte panel.

    Directory of Open Access Journals (Sweden)

    Rajesh Patel

    Full Text Available Targeted anticancer therapies rely on the identification of patient subgroups most likely to respond to treatment. Predictive biomarkers play a key role in patient selection, while diagnostic and prognostic biomarkers expand our understanding of tumor biology, suggest treatment combinations, and facilitate discovery of novel drug targets. We have developed a high-throughput microfluidics method for mutation detection (MUT-MAP, mutation multi-analyte panel based on TaqMan or allele-specific PCR (AS-PCR assays. We analyzed a set of 71 mutations across six genes of therapeutic interest. The six-gene mutation panel was designed to detect the most common mutations in the EGFR, KRAS, PIK3CA, NRAS, BRAF, and AKT1 oncogenes. The DNA was preamplified using custom-designed primer sets before the TaqMan/AS-PCR assays were carried out using the Biomark microfluidics system (Fluidigm; South San Francisco, CA. A cross-reactivity analysis enabled the generation of a robust automated mutation-calling algorithm which was then validated in a series of 51 cell lines and 33 FFPE clinical samples. All detected mutations were confirmed by other means. Sample input titrations confirmed the assay sensitivity with as little as 2 ng gDNA, and demonstrated excellent inter- and intra-chip reproducibility. Parallel analysis of 92 clinical trial samples was carried out using 2-100 ng genomic DNA (gDNA, allowing the simultaneous detection of multiple mutations. DNA prepared from both fresh frozen and formalin-fixed, paraffin-embedded (FFPE samples were used, and the analysis was routinely completed in 2-3 days: traditional assays require 0.5-1 µg high-quality DNA, and take significantly longer to analyze. This assay can detect a wide range of mutations in therapeutically relevant genes from very small amounts of sample DNA. As such, the mutation assay developed is a valuable tool for high-throughput biomarker discovery and validation in personalized medicine and cancer drug

  12. Effect of Some Admixtures on the Hydration of Silica Fume and Hydrated Lime

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The effects of sodium salt of naphthalene formaldehyde sulfonic acid and stearic acid on the hydration of silica fume and Ca(0H)2 have been investigated. The hydration was carried out at 60℃ and W/S ratio of 4 for various time intervals namely, 1, 3, 7 and 28 days and in the presence of 0.2% and 5% superplasticizer and stearic acid. The results of the hydration kinetics show that both admixtures accelerate the hydration reaction of silica fume and calcium hydroxide during the first 7 days. Whereas, after 28 days hydration there is no significant effect. Generally, most of free calcium hydroxide seems to be consumed after 28 days. In addition, the phase composition as well as the microstructure of the formed hydrates was examined by using X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) respectively.

  13. Determining ancestry proportions in complex admixture scenarios in South Africa using a novel proxy ancestry selection method.

    Directory of Open Access Journals (Sweden)

    Emile R Chimusa

    Full Text Available Admixed populations can make an important contribution to the discovery of disease susceptibility genes if the parental populations exhibit substantial variation in susceptibility. Admixture mapping has been used successfully, but is not designed to cope with populations that have more than two or three ancestral populations. The inference of admixture proportions and local ancestry and the imputation of missing genotypes in admixed populations are crucial in both understanding variation in disease and identifying novel disease loci. These inferences make use of reference populations, and accuracy depends on the choice of ancestral populations. Using an insufficient or inaccurate ancestral panel can result in erroneously inferred ancestry and affect the detection power of GWAS and meta-analysis when using imputation. Current algorithms are inadequate for multi-way admixed populations. To address these challenges we developed PROXYANC, an approach to select the best proxy ancestral populations. From the simulation of a multi-way admixed population we demonstrate the capability and accuracy of PROXYANC and illustrate the importance of the choice of ancestry in both estimating admixture proportions and imputing missing genotypes. We applied this approach to a complex, uniquely admixed South African population. Using genome-wide SNP data from over 764 individuals, we accurately estimate the genetic contributions from the best ancestral populations: isiXhosa [Formula: see text], ‡Khomani SAN [Formula: see text], European [Formula: see text], Indian [Formula: see text], and Chinese [Formula: see text]. We also demonstrate that the ancestral allele frequency differences correlate with increased linkage disequilibrium in the South African population, which originates from admixture events rather than population bottlenecks.The collective term for people of mixed ancestry in southern Africa is "Coloured," and this is officially recognized in South

  14. Mapping out Map Libraries

    Directory of Open Access Journals (Sweden)

    Ferjan Ormeling

    2008-09-01

    Full Text Available Discussing the requirements for map data quality, map users and their library/archives environment, the paper focuses on the metadata the user would need for a correct and efficient interpretation of the map data. For such a correct interpretation, knowledge of the rules and guidelines according to which the topographers/cartographers work (such as the kind of data categories to be collected, and the degree to which these rules and guidelines were indeed followed are essential. This is not only valid for the old maps stored in our libraries and archives, but perhaps even more so for the new digital files as the format in which we now have to access our geospatial data. As this would be too much to ask from map librarians/curators, some sort of web 2.0 environment is sought where comments about data quality, completeness and up-to-dateness from knowledgeable map users regarding the specific maps or map series studied can be collected and tagged to scanned versions of these maps on the web. In order not to be subject to the same disadvantages as Wikipedia, where the ‘communis opinio’ rather than scholarship, seems to be decisive, some checking by map curators of this tagged map use information would still be needed. Cooperation between map curators and the International Cartographic Association ( ICA map and spatial data use commission to this end is suggested.

  15. Laser-scanning astrocyte mapping reveals increased glutamate-responsive domain size and disrupted maturation of glutamate uptake following neonatal cortical freeze-lesion

    Directory of Open Access Journals (Sweden)

    Mortiz eArmbruster

    2014-09-01

    Full Text Available Astrocytic uptake of glutamate shapes extracellular neurotransmitter dynamics, receptor activation, and synaptogenesis. During development, glutamate transport becomes more robust. How neonatal brain insult affects the functional maturation of glutamate transport remains unanswered. Neonatal brain insult can lead to developmental delays, cognitive losses, and epilepsy; the disruption of glutamate transport is known to cause changes in synaptogenesis, receptor activation, and seizure. Using the neonatal freeze-lesion (FL model, we have investigated how insult affects the maturation of astrocytic glutamate transport. As lesioning occurs on the day of birth, a time when astrocytes are still functionally immature, this model is ideal for identifying changes in astrocyte maturation following insult. Reactive astrocytosis, astrocyte proliferation, and in vitro hyperexcitability are known to occur in this model. To probe astrocyte glutamate transport with better spatial precision we have developed a novel technique, Laser Scanning Astrocyte Mapping (LSAM, which combines glutamate transport current (TC recording from astrocytes with laser scanning glutamate photolysis. LSAM allows us to identify the area from which a single astrocyte can transport glutamate and to quantify spatial heterogeneity in the rate of glutamate clearance kinetics within that domain. Using LSAM, we report that cortical astrocytes have an increased glutamate-responsive area following FL and that TCs have faster decay times in distal, as compared to proximal processes. Furthermore, the developmental shift from GLAST- to GLT-1-dominated clearance is disrupted following FL. These findings introduce a novel method to probe astrocyte glutamate uptake and show that neonatal cortical FL disrupts the functional maturation of cortical astrocytes.

  16. Ancestry inference in complex admixtures via variable-length Markov chain linkage models.

    Science.gov (United States)

    Rodriguez, Jesse M; Bercovici, Sivan; Elmore, Megan; Batzoglou, Serafim

    2013-03-01

    Inferring the ancestral origin of chromosomal segments in admixed individuals is key for genetic applications, ranging from analyzing population demographics and history, to mapping disease genes. Previous methods addressed ancestry inference by using either weak models of linkage disequilibrium, or large models that make explicit use of ancestral haplotypes. In this paper we introduce ALLOY, an efficient method that incorporates generalized, but highly expressive, linkage disequilibrium models. ALLOY applies a factorial hidden Markov model to capture the parallel process producing the maternal and paternal admixed haplotypes, and models the background linkage disequilibrium in the ancestral populations via an inhomogeneous variable-length Markov chain. We test ALLOY in a broad range of scenarios ranging from recent to ancient admixtures with up to four ancestral populations. We show that ALLOY outperforms the previous state of the art, and is robust to uncertainties in model parameters. PMID:23421795

  17. Integration of UAV-Based Photogrammetry and Terrestrial Laser Scanning for the Three-Dimensional Mapping and Monitoring of Open-Pit Mine Areas

    Directory of Open Access Journals (Sweden)

    Xiaohua Tong

    2015-05-01

    Full Text Available This paper presents a practical framework for the integration of unmanned aerial vehicle (UAV based photogrammetry and terrestrial laser scanning (TLS with application to open-pit mine areas, which includes UAV image and TLS point cloud acquisition, image and cloud point processing and integration, object-oriented classification and three-dimensional (3D mapping and monitoring of open-pit mine areas. The proposed framework was tested in three open-pit mine areas in southwestern China. (1 With respect to extracting the conjugate points of the stereo pair of UAV images and those points between TLS point clouds and UAV images, some feature points were first extracted by the scale-invariant feature transform (SIFT operator and the outliers were identified and therefore eliminated by the RANdom SAmple Consensus (RANSAC approach; (2 With respect to improving the accuracy of geo-positioning based on UAV imagery, the ground control points (GCPs surveyed from global positioning systems (GPS and the feature points extracted from TLS were integrated in the bundle adjustment, and three scenarios were designed and compared; (3 With respect to monitoring and mapping the mine areas for land reclamation, an object-based image analysis approach was used for the classification of the accuracy improved UAV ortho-image. The experimental results show that by introduction of TLS derived point clouds as GCPs, the accuracy of geo-positioning based on UAV imagery can be improved. At the same time, the accuracy of geo-positioning based on GCPs form the TLS derived point clouds is close to that based on GCPs from the GPS survey. The results also show that the TLS derived point clouds can be used as GCPs in areas such as in mountainous or high-risk environments where it is difficult to conduct a GPS survey. The proposed framework achieved a decimeter-level accuracy for the generated digital surface model (DSM and digital orthophoto map (DOM, and an overall accuracy of 90

  18. Stabilization of Dune Sand with Ceramic Tile Waste as Admixture

    OpenAIRE

    Dr. N. K. Ameta

    2013-01-01

    The Dune-Sand has nil cohesion and thus has a very low compressive strength. The stabilization of Dune-Sand is of prime importance since it can be used for various construction works and highways, airfields and helipads projects. The investigation reported herein presents a study of stabilization of Dune- Sand with Ceramic Tiles Wastage as admixture. All the California Bearing Ratio tests were conducted at maximum dry density and optimum moisture content as arrived from Standard Proctor Test....

  19. Venous admixture in COPD: Pathophysiology and therapeutic approaches

    OpenAIRE

    Cooper, CB; Celli, B

    2008-01-01

    Chronic obstructive and interstitial lung diseases impair pulmonary gas exchange leading to wasted ventilation (alveolar dead space) and wasted perfusion (venous admixture). These two fundamental types of abnormality represent opposite ends of the spectrum of ventilation-perfusion mismatch with V̇/Q̇ ratios of infinity and zero. Treatment approaches that improve airway function, reduce air trapping and hyperinflation have received much attention and might be successful at ameliorating the pro...

  20. Mirror matter admixtures in K_L to mu^+ mu^-

    CERN Document Server

    Sánchez-Colón, G; Sanchez-Colon, Gabriel; Garcia, Augusto

    2006-01-01

    Our previous analysis on the contributions of mirror matter admixtures in ordinary hadrons to K_L to gamma gamma is extended to study the relevance of such contributions to the K_L to mu^+ mu^- rare decay. The mixing angle of the admixtures previously determined to describe the enhancement phenomenon in two body non-leptonic decays of strange hadrons is used, along with recent results for the description of the strong and electromagnetic interaction parts of the transition amplitudes. We find that these admixtures give a significant contribution with a small SU(3) breaking of only 2.8%, we also find a value of \\sim -17.9^{\\circ} for the eta-eta' mixing angle consistent with some of its determinations in the literature and a preferred negative value around -16 for the local counter-term contribution chi_1 + chi_2 consistent with the existence of a unique counter-term assuming lepton universality. We conclude that those mixings may be relevant in low energy physics and should not be ignored.

  1. Genome-wide analysis in Brazilian Xavante Indians reveals low degree of admixture.

    Directory of Open Access Journals (Sweden)

    Patricia C Kuhn

    Full Text Available Characterization of population genetic variation and structure can be used as tools for research in human genetics and population isolates are of great interest. The aim of the present study was to characterize the genetic structure of Xavante Indians and compare it with other populations. The Xavante, an indigenous population living in Brazilian Central Plateau, is one of the largest native groups in Brazil. A subset of 53 unrelated subjects was selected from the initial sample of 300 Xavante Indians. Using 86,197 markers, Xavante were compared with all populations of HapMap Phase III and HGDP-CEPH projects and with a Southeast Brazilian population sample to establish its population structure. Principal Components Analysis showed that the Xavante Indians are concentrated in the Amerindian axis near other populations of known Amerindian ancestry such as Karitiana, Pima, Surui and Maya and a low degree of genetic admixture was observed. This is consistent with the historical records of bottlenecks experience and cultural isolation. By calculating pair-wise F(st statistics we characterized the genetic differentiation between Xavante Indians and representative populations of the HapMap and from HGDP-CEPH project. We found that the genetic differentiation between Xavante Indians and populations of Ameridian, Asian, European, and African ancestry increased progressively. Our results indicate that the Xavante is a population that remained genetically isolated over the past decades and can offer advantages for genome-wide mapping studies of inherited disorders.

  2. 复杂环境下矿物掺合料混凝土的耐久性研究%Study on Mineral Admixture Concrete Durability under the Complex Environment

    Institute of Scientific and Technical Information of China (English)

    陈剑毅; 胡明玉; 肖烨; 李建平

    2011-01-01

    Using fly ash, slag, diatomite and zeolite as mineral admixtures, by designing orthogonal test with types and dosages of mineral admixtures for concrete improvement, to study the concrete durability adding various different active mineral admixtures under the complex conditions of chloride, sulfate and freeze-thaw erosion, to get the types and dosages of mineral admixtures of the best durability concrete by analyze of experimental results, with the aid of analysis methods such as X-ray diffraction and scanning electron microscope, study micro-mechanism of concrete improvement mixing mineral admixtures. The research results show that the mineral admixtures can restrict the formation of Thaumasite and improving the concrete pore structure, in order to improve evidently the concrete durabilyty, and diatomite is the best mineral admixture among them.%以粉煤灰、矿渣、硅藻土和沸石作为矿物掺合料,通过设计矿物掺合料种类和掺量对混凝土改性的正交试验,研究在氯盐-硫酸盐-冻融复杂环境下掺活性矿物掺合料混凝土的耐久性,并通过X射线衍射和扫描电子显微镜分析,探求矿物掺合料对混凝土改性的微观机理.研究表明,矿物掺合料能够抑制碳硫硅钙石晶体的生成和改善混凝土孔结构,从而明显提高混凝土的耐久性,其中硅藻土效果最佳.

  3. Nuclear Scans

    Science.gov (United States)

    Nuclear scans use radioactive substances to see structures and functions inside your body. They use a special ... images. Most scans take 20 to 45 minutes. Nuclear scans can help doctors diagnose many conditions, including ...

  4. Experimental Study on Durability Improvement of Fly Ash Concrete with Durability Improving Admixture

    OpenAIRE

    Quan, Hong-zhu; Kasami, Hideo

    2014-01-01

    In order to improve the durability of fly ash concrete, a series of experimental studies are carried out, where durability improving admixture is used to reduce drying shrinkage and improve freezing-thawing resistance. The effects of durability improving admixture, air content, water-binder ratio, and fly ash replacement ratio on the performance of fly ash concrete are discussed in this paper. The results show that by using durability improving admixture in nonair-entraining fly ash concrete,...

  5. Polycarboxylate superplasticiser admixtures: effect on hydration, microstructure and rheological behaviour in cement pastes

    OpenAIRE

    Puertas, F.; Santos, H.; Palacios, M.; Martínez-Ramírez, Sagrario

    2005-01-01

    A study was conducted on the effect of a polycarboxylate (PC) admixture on the mechanical, mineralogical, microstructural and rheological behaviour of Portland cement pastes. It was observed that the presence of PC admixture retards the initial cement hydration reactions, although this effect may be offset by possible increased diffusion in later stages. Additionally, the PC admixtures produce a few alterations in the structure and composition of the formed C–S–H gel. The addition of 1% PC...

  6. Practical handling of AIO admixtures – Guidelines on Parenteral Nutrition, Chapter 10

    Directory of Open Access Journals (Sweden)

    Stanga, Z.

    2009-11-01

    Full Text Available All-in-one admixtures (AIO-admixtures provide safe, effective and low-risk PN (parenteral nutrition for practically all indications and applications. Water, energy (carbohydrates and lipids, amino acids, vitamins and trace elements are infused together with PN either as industrially-manufactured AIO admixtures provided as two- or three-chamber bags (shelf life usually more than 12 months completed with electrolytes and micronutrients where appropriate or as individually compounded ready-to-use AIO admixtures (compounding, usually prepared by a pharmacy on either a daily or weekly basis and stored at 2–8°C. Physico-chemical and microbial stability of an AIO admixture is essential for the safety and effectiveness of patient-specific PN, and its assurance requires specialist pharmaceutical knowledge. The stability should be documented for an application period of 24 (–48 hours. It is advisable to offer a limited selection of different PN regimes in each hospital. For reasons of drug and medication safety, PN admixtures prepared for individual patients must be correctly labelled and specifications for storage conditions must also be followed during transport. Monitoring is required where applicable. Micronutrients are usually administered separately to AIO admixtures. In case compatibility and stability have been well documented trace elements and/or combination preparations including water-soluble or water-soluble/fat soluble vitamin supplements can be added to PN admixtures under strict aseptic conditions. AIO admixtures are usually not used as vehicles for drugs (incompatibilities.

  7. Effect of Anti-freezing Admixtures on Alkali-silica Reaction in Mortars

    Institute of Scientific and Technical Information of China (English)

    LIU Junzhe; LI Yushun; LV Lihua

    2005-01-01

    The influence of anti-freezing admixture on the alkali aggregate reaction in mortar was analyzed with accelerated methods. It is confirmed that the addition of sodium salt ingredients of anti-freezing admixture accelerates the alkali silica reaction to some extent, whereas calcium salt ingredient of anti-freezing admixture reduces the expansion of alkali silica reaction caused by high alkali cement. It is found that the addition of the fly ash considerably suppresses the expansion of alkali silica reaction induced by the anti-freezing admixtures.

  8. The influence of shrinkage reducing admixtures on plastic shrinkage

    Directory of Open Access Journals (Sweden)

    Mora, J.

    2003-12-01

    Full Text Available Shrinkage reducing admixtures (SRAs are viable alternatives for reducing plastic shrinkage cracking in concrete. The objective of the present paper is to study early age plastic shrinkage in restrained concrete elements, where three different SRAs have been used. The influence of the admixture is analyzed through the following measurements: capillary pressure, evaporation, temperature evolution, crack evolution and settlement. The tests for studying the cracking and deformation were made on two different configurations (i.e., restrained prisms with reduced cross-section and restrained panel, in a wind tunnel, with controlled wind temperature and velocity. The conclusions obtained indicate the viability of the use of this type of admixture and the usefulness of the test methods.

    Los aditivos reductores de retracción (SRAs se plantean, hoy en día, como una alternativa viable para reducir la fisuración por retracción plástica. El objetivo del presente artículo es conocer mejor y predecir el comportamiento a primeras edades de la retracción plástica en elementos estructurales coaccionados, a los que se les ha añadido diversos aditivos reductores de retracción (tres tipos diferentes. Esta influencia se analiza a través de las siguientes propiedades: presión capilar, evaporación, evolución de temperaturas, evolución de fisuración, y deformaciones verticales de asentamiento. Los ensayos para estudiar la fisuración y las deformaciones se han realizado sobre diferentes configuraciones (prisma restringido con estrangulamiento y panel restringido, en un túnel de viento, con temperaturas y velocidades de viento controladas. Las conclusiones obtenidas señalan la viabilidad del empleo de este tipo de aditivos y la bondad de los métodos experimentales utilizados.

  9. Mirror matter admixtures in K_S to gamma gamma

    CERN Document Server

    Sánchez-Colón, G; Sanchez-Colon, Gabriel; Garcia, Augusto

    2006-01-01

    The latest measurement of the K_S to gamma gamma branching ratio clearly shows an enhancement over the current theoretical prediction. As in other K and B meson decays, this invites to consider the possibility of the contribution of new physics. We study a particular form of the latter, which may be referred to as manifest mirror symmetry. The experimental data are described using previously determined values for the mixing angles of the admixtures of mirror matter in ordinary hadrons and by assuming that for pi^0, eta, eta', the mirror decay amplitudes have the same magnitudes as their ordinary counterparts.

  10. Symmetry limit properties of decay amplitudes with mirror matter admixtures

    CERN Document Server

    Sánchez-Colón, G; Sanchez-Colon, Gabriel; Garcia, Augusto

    2006-01-01

    We extend our previous analysis on the symmetry limit properties of non-leptonic and weak radiative decay amplitudes of hyperons in a scheme of mirror matter admixtures in physical hadrons to include the two-body non-leptonic decays of $\\Omega^-$ and the two photon and two pion decays of kaons. We show that the so-called parity-conserving amplitudes predicted for all the decays vanish in the strong flavor SU(3) symmetry limit. We also establish the specific conditions under which the corresponding so-called parity-violating amplitudes vanish in the same limit.

  11. Effect of polycarboxylate admixture structure on cement paste rheology

    OpenAIRE

    Aranda, M. A. G.; De la Torre, A.G.; Puertas, F.; Palacios, M.; Alonso, M M

    2007-01-01

    The purpose of the present study was to analyze the effect of the structural differences in four polycarboxylate and polyether admixtures on the rheological properties of cement pastes with different chemical and mineralogical compositions and different active additions (CEM I 42.5 R, CEM I 52.5 R, CEM I 52.5 N/SR, CEM II/AV 42.5R, CEM II/B-L 32.5 R, CEM III/B 32.5R, BL I 52.5R and CAC – European standard EN 197-1:2000). The results of the minislump test concurred with the variations ob...

  12. Whistler Solitons in Plasma with Anisotropic Hot Electron Admixture

    Science.gov (United States)

    Khazanov, G. V.; Krivorutsky, E. N.; Gallagher, D. L.

    1999-01-01

    The longitudinal and transverse modulation instability of whistler waves in plasma, with a small admixture of hot anisotropic electrons, is discussed. If the hot particles temperature anisotropy is positive, it is found that, in such plasma, longitudinal perturbations can lead to soliton formation for frequencies forbidden in cold plasma. The soliton is enriched by hot particles. The frequency region unstable to transverse modulation in cold plasma in the presence of hot electrons is divided by stable domains. For both cases the role of hot electrons is more significant for whistlers with smaller frequencies.

  13. Influence of chloride admixtures on cement matrix durability

    International Nuclear Information System (INIS)

    The influence of various inorganic salts, as chloride admixtures to Portland cement, on the mechanical properties and the durability of the matrix has been studied. The salts used in this study are chromium, nickel and cadmium chlorides. Improved compressive strength values are obtained which have been correlated to the stable metal hydroxide formation in high pH environment. Under static water conditions at 500C, hydrolyzed chloride ions exhibit adverse effects on the matrix durability through rapid release of calcium as calcium chloride in the initial period of leaching. On the contrary, enhanced matrix durability is obtained on long term leaching in the case of cement containing chromium chloride

  14. Physicochemical compatibility of nebulizable drug admixtures containing colistimethate and tobramycin.

    Science.gov (United States)

    Wollstadt, A; Krämer, I; Kamin, W

    2013-09-01

    Inhalation therapy with nebulizable antibiotic drugs is a mainstay in treating Pseudomonas aeruginosa infections in cystic fibrosis patients. The combination of tobramycin and colistin was found to be superior to monotherapy in killing P. aeruginosa in biofilms. The simultaneous inhalation of tobramycin and colistin might be an option to increase the compliance of patients. The objective of this in-vitro study was to determine whether admixtures of inhalation solutions containing colistin methanesulfonate (CMS) and tobramycin are physicochemically compatible. Physical compatibility was determined by measuring pH and osmolality. Chemical compatibility was determined by testing the antibiotic activity of the mixtures by the pharmacopoeial microbiological assay and comparing the results to those of standard solutions. Samples were analyzed immediately after mixing and after 24 h. Values of pH and osmolality remained unchanged and in physiologically acceptable ranges. Neither for colistin methanesulfonate (CMS) nor for tobramycin losses of antibiotic potency were registered at any time. Admixtures of nebulizer solutions containing CMS and tobramycin were shown to be physicochemically compatible. Further investigations are needed to determine whether drug delivery is affected by mixing the nebulizer solutions to ensure that simultaneous inhalation is recommendable. PMID:24147342

  15. Incorporation of Mineral Admixtures in Sustainable High Performance Concrete

    Directory of Open Access Journals (Sweden)

    Nima Farzadnia

    2011-07-01

    Full Text Available Concrete is a widely used construction material around the world, and its properties have been undergoing changes through technological advancement. Numerous types of concrete have been developed to enhance the different properties of concrete. So far, this development can be divided into four stages. The earliest is the traditional normal strength concrete which is composed of only four constituent materials, which are cement, water, fine and coarse aggregates. With a fast population growth and a higher demand for housing and infrastructure, accompanied by recent developments in civil engineering, such as high-rise buildings and long-span bridges, higher compressive strength concrete was needed. At the beginning, reducing the water-cement ratio was the easiest way to achieve the high compressive strength. Thereafter, the fifth ingredient, a water reducing agent or super plasticizer, was indispensable. However, sometimes the compressive strength was not as important as some other properties, such as low permeability, durability and workability. Thus, high performance concrete was proposed and widely studied at the end of the last century. Currently, high-performance concrete is used in massive volumes due to its technical and economic advantages. Such materials are characterized by improved mechanical and durability properties resulting from the use of chemical and mineral admixtures as well as specialized production processes. This paper reviews the incorporation of mineral admixtures in binary, ternary and quaternary blended mortars in concrete.

  16. Advanced Network Scanning

    Directory of Open Access Journals (Sweden)

    Ashiqur Rahman

    2016-07-01

    Full Text Available Network scanning is à procedure for identifying active hosts on a network, either for the purpose of attacking them or for network security assessment. Scanning procedures, such as ping sweeps and port scans, return information about which IP addresses map to live hosts that are active on the Internet and what services they offer. Another scanning method, inverse mapping, returns information about what IP addresses do not map to live hosts; this enables an attacker to make assumptions about viable addresses. Scanning is one of three components of intelligence gathering for an attacker. In the foot printing phase, the attacker creates a profile of the target organization, with information such as its domain name system (DNS and e-mail servers, and its IP address range. Most of this information is available online. In the scanning phase, the attacker finds information about the specific IP addresses that can be accessed over the Internet, their operating systems, the system architecture, and the services running on each computer. In the enumeration phase, the attacker gathers information such as network user and group names, routing tables, and Simple Network Management Protocol (SNMP data

  17. The application study of polycarboxylates water-reducing admixture in passenger dedicated line engineering%The application study of polycarboxylates water-reducing admixture in passenger dedicated line engineering

    Institute of Scientific and Technical Information of China (English)

    Huang Zhijiu

    2012-01-01

    Polycarboxylate water-reducing admixture possesses the capability which could meet with the comprehensive performance of high performance concrete used in passenger dedicated line engineering. The problems of polycarboxylates water-reducing admixtures existed in the engineering application of were analyzed. At present the key for polycarboxylates application was to settle the compatibility between the water-reducing admixture and the cement and to keep the quality retention of this admixture.

  18. Harmful admixtures assessment in sinter mixtures used in iron ore sinter plants in Poland

    Directory of Open Access Journals (Sweden)

    J. Korol

    2014-10-01

    Full Text Available In this study composition of sinter mixtures used in Polish sinter plants were established. Seven sinter mixtures composition were examined, based on iron-bearing materials, admixtures and fuels. Contents of harmful admixtures were examined according to three kinds of environmental impacts: emissions of SOx, heavy metals, polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/PCDFs.

  19. Fly Ash Admixture and its Influence on Alitic Type Cement Concrete Permeability

    OpenAIRE

    Rujanu, Mircea; Rujanu, Bogdan

    2012-01-01

    Experimental and theoretical studies pointed that adding fly ash in concrete composition, could favour its impermeability characteristic improvement. It is known, also, that fly ash admixture achieves cement dosage reduction, so that concrete will be cheaper, and in this conditions it is important to analyse fly ash admixture influence on impermeability degree, too.

  20. Patterns of admixture and population structure in native populations of Northwest North America.

    Directory of Open Access Journals (Sweden)

    Paul Verdu

    2014-08-01

    Full Text Available The initial contact of European populations with indigenous populations of the Americas produced diverse admixture processes across North, Central, and South America. Recent studies have examined the genetic structure of indigenous populations of Latin America and the Caribbean and their admixed descendants, reporting on the genomic impact of the history of admixture with colonizing populations of European and African ancestry. However, relatively little genomic research has been conducted on admixture in indigenous North American populations. In this study, we analyze genomic data at 475,109 single-nucleotide polymorphisms sampled in indigenous peoples of the Pacific Northwest in British Columbia and Southeast Alaska, populations with a well-documented history of contact with European and Asian traders, fishermen, and contract laborers. We find that the indigenous populations of the Pacific Northwest have higher gene diversity than Latin American indigenous populations. Among the Pacific Northwest populations, interior groups provide more evidence for East Asian admixture, whereas coastal groups have higher levels of European admixture. In contrast with many Latin American indigenous populations, the variance of admixture is high in each of the Pacific Northwest indigenous populations, as expected for recent and ongoing admixture processes. The results reveal some similarities but notable differences between admixture patterns in the Pacific Northwest and those in Latin America, contributing to a more detailed understanding of the genomic consequences of European colonization events throughout the Americas.

  1. Effects of Leaching Behavior of Calcium Ions on Compression and Durability of Cement-based Materials with Mineral Admixtures

    Directory of Open Access Journals (Sweden)

    Wei-Ting Lin

    2013-05-01

    Full Text Available Leaching of calcium ions increases the porosity of cement-based materials, consequently resulting in a negative effect on durability since it provides an entry for aggressive harmful ions, causing reinforcing steel corrosion. This study investigates the effects of leaching behavior of calcium ions on the compression and durability of cement-based materials. Since the parameters influencing the leaching behavior of cement-based materials are unclear and diverse, this paper focuses on the influence of added mineral admixtures (fly ash, slag and silica fume on the leaching behavior of calcium ions regarding compression and durability of cemented-based materials. Ammonium nitrate solution was used to accelerate the leaching process in this study. Scanning electron microscopy, X-ray diffraction analysis, and thermogravimetric analysis were employed to analyze and compare the cement-based material compositions prior to and after calcium ion leaching. The experimental results show that the mineral admixtures reduce calcium hydroxide quantity and refine pore structure through pozzolanic reaction, thus enhancing the compressive strength and durability of cement-based materials.

  2. Identification of admixture for pelletization and strength enhancement of sintered coal pond ash aggregate through statistically designed experiments

    International Nuclear Information System (INIS)

    Highlights: • Sintered aggregate using pond ash from lignite and bituminous coal source. • Identification of admixtures and its dosage through design of experiments. • Clay, bentonite and kaolinite as binders enhance the strength of aggregate. • Use of calcium hydroxide with clay binder enhanced pelletization efficiency. • Use of borax with clay binders enhanced the strength of aggregate. - Abstract: Statistically designed experiments using Response Surface Methodology have been undertaken to identify the parameters influencing manufacturing process and properties of aggregate using coal pond ash (generated from bituminous and lignite coal sources). Based on the preliminary studies, Ca(OH)2 and borax have been identified as pelletization and strength enhancing admixture respectively. Pelletization efficiency of bituminous and lignite pond ash increased with an increase in binder and Ca(OH)2 dosage to 20–98% and 50–98% respectively, with proportionate quantity of water. Sintering has been used as a hardening method with temperature range of 900 °C and 1100 °C for a duration range of 45–120 min. Phase composition and sintered microstructure of aggregate has been reported using X-ray diffraction and scanning electron microscopy respectively. The ten percent fines value of aggregate with clay binder was 5.5 tonne as against a value of 4.5 tonne with aggregate with bentonite binder. Among the binders studied, bentonite resulted in high volume utilization of pond ash, i.e. up to 88%

  3. CT Scans

    Science.gov (United States)

    ... cross-sectional pictures of your body. Doctors use CT scans to look for Broken bones Cancers Blood clots Signs of heart disease Internal bleeding During a CT scan, you lie still on a table. The table ...

  4. Thyroid scan

    Science.gov (United States)

    ... PET scan Skin nodules Thyroid cancer Thyroid cancer - medullary carcinoma Thyroid cancer - papillary carcinoma Toxic nodular goiter ... Topics Hyperthyroidism Hypothyroidism Nuclear Scans Thyroid Cancer Thyroid Diseases Thyroid Tests Browse the Encyclopedia A.D.A. ...

  5. Viscosity and Electrical Conductivity of the Liquid Sn-3.8Ag-0.7Cu Alloy with Minor Co Admixtures

    Science.gov (United States)

    Yakymovych, A.; Sklyarchuk, V.; Plevachuk, Yu.; Sokoliuk, B.

    2016-10-01

    The viscosity and electrical conductivity as structure-sensitive transport properties of the liquid metals and alloys are important for modeling of the melting and solidification processes. The viscosity and electrical conductivity data provide additional information about the influence of impurities on the structure and physicochemical properties of the liquid metal matrix, which is useful for understanding of structural transformations in the liquid state. In the present work, an impact of minor Co admixtures on the viscosity and electrical conductivity of liquid Sn-3.8Ag-0.7Cu alloy was studied. An increase in viscosity with minor Co admixtures is in a satisfactory agreement with model predicted data obtained from thermodynamic approaches and suggests a significant impact of interatomic interactions. Cobalt admixtures significantly affect the electrical conductivity, which gradually decreases with increasing the amount of Co. Additionally, the sample microstructure has been examined using x-ray diffraction and scanning electron microscopy analyses. The formation of Sn-based Co-Sn intermetallic compounds was detected in the alloys with more than 1 wt.% Co.

  6. Viscosity and Electrical Conductivity of the Liquid Sn-3.8Ag-0.7Cu Alloy with Minor Co Admixtures

    Science.gov (United States)

    Yakymovych, A.; Sklyarchuk, V.; Plevachuk, Yu.; Sokoliuk, B.

    2016-08-01

    The viscosity and electrical conductivity as structure-sensitive transport properties of the liquid metals and alloys are important for modeling of the melting and solidification processes. The viscosity and electrical conductivity data provide additional information about the influence of impurities on the structure and physicochemical properties of the liquid metal matrix, which is useful for understanding of structural transformations in the liquid state. In the present work, an impact of minor Co admixtures on the viscosity and electrical conductivity of liquid Sn-3.8Ag-0.7Cu alloy was studied. An increase in viscosity with minor Co admixtures is in a satisfactory agreement with model predicted data obtained from thermodynamic approaches and suggests a significant impact of interatomic interactions. Cobalt admixtures significantly affect the electrical conductivity, which gradually decreases with increasing the amount of Co. Additionally, the sample microstructure has been examined using x-ray diffraction and scanning electron microscopy analyses. The formation of Sn-based Co-Sn intermetallic compounds was detected in the alloys with more than 1 wt.% Co.

  7. Stabilization of Dune Sand with Ceramic Tile Waste as Admixture

    Directory of Open Access Journals (Sweden)

    Dr. N. K. Ameta

    2013-09-01

    Full Text Available The Dune-Sand has nil cohesion and thus has a very low compressive strength. The stabilization of Dune-Sand is of prime importance since it can be used for various construction works and highways, airfields and helipads projects. The investigation reported herein presents a study of stabilization of Dune- Sand with Ceramic Tiles Wastage as admixture. All the California Bearing Ratio tests were conducted at maximum dry density and optimum moisture content as arrived from Standard Proctor Test. Direct shear tests were also performed. The main objective of this experimental study was to obtain an economical stabilized mix of ceramic tiles wastage and dune sand so that largely and cheaply available dune-sand be used for various construction purposes.

  8. Estimating individual admixture proportions from next generation sequencing data

    DEFF Research Database (Denmark)

    Skotte, Line; Korneliussen, Thorfinn Sand; Albrechtsen, Anders

    2013-01-01

    Inference of population structure and individual ancestry is important both for population genetics and for association studies. With next generation sequencing technologies it is possible to obtain genetic data for all accessible genetic variations in the genome. Existing methods for admixture...... analysis rely on known genotypes. However, individual genotypes cannot be inferred from low-depth sequencing data without introducing errors. This article presents a new method for inferring an individual's ancestry that takes the uncertainty introduced in next generation sequencing data into account....... This is achieved by working directly with genotype likelihoods that contain all relevant information of the unobserved genotypes. Using simulations as well as publicly available sequencing data, we demonstrate that the presented method has great accuracy even for very low-depth data. At the same time, we...

  9. 3D Laser Scanning Technology-based Historic Building Mapping for Historic Preservation: A Case Study of Shang Shu Di in Fujian Province, China

    OpenAIRE

    Yuanyi, Zhang; Zhang, Ying; Zhenjiang, Shen; Nishino, Tatsuya; Xiaojuan, Chen

    2015-01-01

    Historic preservation, adaptive reuse, and sustainable urban design that considers the full range of social, environmental, and economic factors is an essential component of sustainable urban development, while the mapping of historic buildings which can be archived and extracted for application, is the basic work on the protection of historic buildings and adaptive reuse. Traditional mapping methods need more time and more workers, and there are measured omissions, mistakes and other issues ...

  10. A factorial design study on the physical stability of 3-in-1 admixtures.

    Science.gov (United States)

    Li, L C; Sampogna, T P

    1993-11-01

    The effects of dextrose concentration, the compounding method, and storage conditions, on the physical stability of 3-in-1 admixtures were investigated using a 2n factorial design. The main effect of these three variables on the weight percent of oil globules larger than 5 microns (by HIAC) was found to be statistically significant. However, the effects of interaction amongst these variables, except the two-way interaction between dextrose concentration and storage conditions, were found to be statistically insignificant. A higher dextrose concentration was shown to enhance the physical stability of the admixtures, while low-temperature storage (three days at 5 degrees C) was more favourable for maintaining the physical stability of the admixtures with a low dextrose concentration. Although sequential pumping produced admixtures with a slightly lower final weight percentage of larger oil globules (> 5 microns), the method of compounding has the least impact on the physical stability of the admixtures in comparison with the other two variables evaluated in this study. The storage of the admixtures at room temperature for one day was shown to have a greater adverse effect on admixtures with a low dextrose concentration. PMID:7908042

  11. Finding new solutions in pediatric parenteral admixtures: how to improve quality and to deal with shortages

    Directory of Open Access Journals (Sweden)

    Dorota Watrobska-Swietlikowska

    2014-07-01

    Full Text Available Introduction: Pediatric parenteral nutrition enables normal growth even of preterm infants. Those children require, however, tailored parenteral nutrition and the creation of such can be challenging due to the risk of instability and shortages. Objective: Prototypical parenteral admixtures were created using different calcium salts (organic and inorganic and different lipid emulsions and tested for stability. 36 of parenteral admixtures containing two types of calcium salts: chloride or gluconolactobionate and different lipid emulsions (SMOFlipid® or Lipofundin MCT/LCT® were under investigation. Methods: Preliminary admixtures were prepared in two-chamber bags whereas lipid emulsions were placed separately in the second chamber. Pre-admixtures were stored for up to 21 days at +4ºC. Contents of the two chambers were combined at t = 0 or after 21 days of storage. Physical analysis of completed admixtures (visual inspection, microscopic observation, pH measurement and determination of the size distribution of oily droplets was carried out after 21 days of the storage. Stability of lipid, commercial emulsions stored in ethylene vinyl acetate (EVA bags for 42 days was also studied. Results: Irrespectively of the time of storage of preadmixtures and type of calcium salt and different lipid emulsions among 36 total parenteral admixtures only one showed signs of destabilization after preparation and one was unstable when stored for longer than 14 days. All other formulations were qualified to be stable during the study. All investigated commercial lipid emulsions were physically stable in EVA bags even when stored at room temperature. Conclusion: The study proved that it was possible to store pre-admixture in EVA bags for 21 days at 4ºC as well as that CAN (critical aggregation number and CaxP (the products of multiplication of calcium and phosphate ions concentration should not be used as reliable indicators of admixture physical stability. No

  12. A Genome Scan to Detect Quantitative Trait Loci for Economically Important Traits in Holstein Cattle Using Two Methods and a Dense Single Nucleotide Polymorphism Map

    NARCIS (Netherlands)

    Daetwyler, H.D.; Schenkel, F.S.; Sargolzaei, M.; Robinson, J.A.B.

    2008-01-01

    Genome scans for detection of bovine quantitative trait loci (QTL) were performed via variance component linkage analysis and linkage disequilibrium single-locus regression (LDRM). Four hundred eighty-four Holstein sires, of which 427 were from 10 grandsire families, were genotyped for 9,919 single

  13. Effect of polycarboxylate admixture structure on cement paste rheology

    Directory of Open Access Journals (Sweden)

    Aranda, M. A. G.

    2007-06-01

    Full Text Available The purpose of the present study was to analyze the effect of the structural differences in four polycarboxylate and polyether admixtures on the rheological properties of cement pastes with different chemical and mineralogical compositions and different active additions (CEM I 42.5 R, CEM I 52.5 R, CEM I 52.5 N/SR, CEM II/AV 42.5R, CEM II/B-L 32.5 R, CEM III/B 32.5R, BL I 52.5R and CAC – European standard EN 197-1:2000. The results of the minislump test concurred with the variations observed in the values of the rheological parameters (shear stress and plastic viscosity. The structural characteristic of the admixtures found to play the most prominent role in their fluidizing effect was the proportion of carboxylate (CG and polyether (EG group components. In cements characteristics such as fineness and the C3A/calcium sulphate and C3S/C3A ratios were also observed to be essential to admixture effectiveness. In this regard, the rheological parameters varied most widely in CEM I 52.5N/SR pastes and least in BL I 52.5R cement pastes. Of the additioned cements, the CEM III/B 32.5R pastes, which contained granulated blast furnace slag, showed the highest rises in flowability. Finally, the fluidizing effect of polycarboxylate superplasticizers was much more intense in calcium aluminate cements, although flowability declined rapidly in this material.El objetivo de este trabajo ha sido estudiar el efecto de las diferencias estructurales de cuatro aditivos basados en policarboxilatos y poliéteres sobre las propiedades reológicas de pastas de cemento con diferente composición química, mineralógica y con distintas adiciones activas (CEM I 42,5 R, CEM I 52,5 R, CEM I 52,5 N/SR, CEM II/AV 42,5R, CEM II/ B-L 32,5 R, CEM III/B 32,5R, BL I 52,5R y CAC - Norma EN 197-1:2000. Los resultados obtenidos sobre la fluidez de la pasta en el ensayo del “Minislump” coinciden con la evolución de los valores de los parámetros reológicos (esfuerzo de

  14. A Genome-Wide Search for Greek and Jewish Admixture in the Kashmiri Population

    Science.gov (United States)

    Tashi, Tsewang; Lorenzo, Felipe Ramos; Feusier, Julie Ellen; Mir, Hyder

    2016-01-01

    The Kashmiri population is an ethno-linguistic group that resides in the Kashmir Valley in northern India. A longstanding hypothesis is that this population derives ancestry from Jewish and/or Greek sources. There is historical and archaeological evidence of ancient Greek presence in India and Kashmir. Further, some historical accounts suggest ancient Hebrew ancestry as well. To date, it has not been determined whether signatures of Greek or Jewish admixture can be detected in the Kashmiri population. Using genome-wide genotyping and admixture detection methods, we determined there are no significant or substantial signs of Greek or Jewish admixture in modern-day Kashmiris. The ancestry of Kashmiri Tibetans was also determined, which showed signs of admixture with populations from northern India and west Eurasia. These results contribute to our understanding of the existing population structure in northern India and its surrounding geographical areas. PMID:27490348

  15. Parenteral Admixture Compatibility in Neurosurgery Ward in Prof. Dr. Margono Soekarjo Regional Public Hospital

    Directory of Open Access Journals (Sweden)

    Laksmi Maharani

    2014-03-01

    Full Text Available Parenteral admixtures (intravenous admixtures have been done commonly in hospitals. However, it has a possibility of failures, like incompatibilities and changes in drug stabilities. The aim of this study was to determine the rate of drug incompatibilities in mixing parenteral preparations in neurosurgery ward in Prof. Dr. Margono Soekarjo Regional Public Hospital which undergo physical incompatibility observed in organoleptic. This study was a prospective descriptive research for one month period. Data were collected and analyzed descriptively. The results showed that from 667 parenteral admixtures in neurosurgery ward in Prof Dr Margono Soekarjo Hospital in February 2010, there were 0.45% potential incompatibility and 2.55% actual incompatibility happened. Actual incompatibility shown as crystal 0.17%, sediment 0.17%, and 2.04% was non-permanent haze in phenytoin and sodium chloride or ringer lactate admixtures.

  16. A Genome-Wide Search for Greek and Jewish Admixture in the Kashmiri Population.

    Science.gov (United States)

    Downie, Jonathan M; Tashi, Tsewang; Lorenzo, Felipe Ramos; Feusier, Julie Ellen; Mir, Hyder; Prchal, Josef T; Jorde, Lynn B; Koul, Parvaiz A

    2016-01-01

    The Kashmiri population is an ethno-linguistic group that resides in the Kashmir Valley in northern India. A longstanding hypothesis is that this population derives ancestry from Jewish and/or Greek sources. There is historical and archaeological evidence of ancient Greek presence in India and Kashmir. Further, some historical accounts suggest ancient Hebrew ancestry as well. To date, it has not been determined whether signatures of Greek or Jewish admixture can be detected in the Kashmiri population. Using genome-wide genotyping and admixture detection methods, we determined there are no significant or substantial signs of Greek or Jewish admixture in modern-day Kashmiris. The ancestry of Kashmiri Tibetans was also determined, which showed signs of admixture with populations from northern India and west Eurasia. These results contribute to our understanding of the existing population structure in northern India and its surrounding geographical areas.

  17. Stability of admixture containing morphine sulfate, bupivacaine hydrochloride, and clonidine hydrochloride in an implantable infusion system.

    Science.gov (United States)

    Classen, Ashley M; Wimbish, Gary H; Kupiec, Thomas C

    2004-12-01

    Intrathecal infusion is often performed using drug combinations. This study was conducted to evaluate the stability of the admixture of morphine sulfate, bupivacaine hydrochloride, and clonidine hydrochloride when used in an implantable pump under simulated clinical use conditions. SynchroMed implantable pumps were filled with an admixture and incubated at 37 degrees C for a period of 90 days. Drug admixture stored in glass vials at 4 degrees C and at 37 degrees C served as controls. Samples which included pump reservoir and catheter delivered aliquots were collected every 30 days and analyzed for drug concentrations using a stability-indicating HPLC method. All drugs contained in the admixture were stable and the original concentrations remained greater than 96%. Over 90 days, and with the pump at the simulated body temperature of 37 degrees C, there were no evident heat catalyzed or device catalyzed reactions. PMID:15589086

  18. Admixture analysis and stocking impact assessment in brown trout ( Salmo trutta ), estimated with incomplete baseline data

    DEFF Research Database (Denmark)

    Hansen, Michael Møller; Eg Nielsen, Einar; Bekkevold, Dorte;

    2001-01-01

    Studies of genetic interactions between wild and domesticated fish are often hampered by unavailability of samples from wild populations prior to population admixture. We assessed the utility of a new Bayesian method, which can estimate individual admixture coefficients even with data missing from...... by the mean of individual admixture coefficients. This method proved more informative than a multidimensional scaling analysis of individual-based genetic distances and assignment tests. The results showed almost complete absence of stocked, domesticated trout in samples of trout from the rivers. Consequently......, stocking had little effect on improving fisheries. In one population, the genetic contribution by domesticated trout was small, whereas in the other population, some genetic impact was suggested. Admixture in this sample of anadromous trout despite absence of stocked domesticated trout could be because...

  19. Finding new solutions in pediatric parenteral admixtures: how to improve quality and to deal with shortages

    OpenAIRE

    Dorota Watrobska-Swietlikowska; Anna Kwidzynska; Agnieszka Szlagatys-Sidorkiewicz; Malgorzata Sznitowska; Stanislaw Klek

    2014-01-01

    Introduction: Pediatric parenteral nutrition enables normal growth even of preterm infants. Those children require, however, tailored parenteral nutrition and the creation of such can be challenging due to the risk of instability and shortages. Objective: Prototypical parenteral admixtures were created using different calcium salts (organic and inorganic) and different lipid emulsions and tested for stability. 36 of parenteral admixtures containing two types of calcium salts: chloride or gluc...

  20. Profile of Intravenous Admixture Compatibility in the Intensive Care Unit (ICU Patients

    Directory of Open Access Journals (Sweden)

    Sharly Dwijayanti

    2016-06-01

    Full Text Available which may directly impact to the outcome of treatment to the Intensive Care Unit (ICU patients. The objective of this study was to identify the profile of compatibility and incompatibility among IV admixtures given to the ICU patients. This observational research was conducted prospectively to the patients admitted in the ICU at a private hospital in Surabaya from October–December 2014. In this research, compatibility data of IV drug and its solution was compared with drug brochure and Handbook on Injectable Drugs 17th ed (2013 as references to analyze the compatibility of IV admixtures. The admixture between IV drug and its solvent was classified as compatible, incompatible, no information (NI, not applicable (NA, and not clear (NC, using a specific criteria. There were 1.186 IV drug‑solvent admixtures observed in 39 ICU patients. There were no IV drug-solvent admixtures classified as incompatible in both adult and child patients. Most of IV drugs were admixed with compatible solvents (adults: 72.31%; children: 69.84%. However, according to two of IV drugs compatibility references used in this research, there were some IV drug-solvent admixtures with unknown information about its compatibility that were classified as NI (adults: 19.68%; children: 30.16%. There were a few of IV drug-solvent admixtures classified as NA and NC, of 7.48% and 0.53%, respectively. The lack of information related to compatibility and stability of the IV admixtures emphasize the importance to continually monitor patients’ condition and drug concentration.

  1. Diffusion Decay Coefficient for Chloride Ions of Concrete Containing Mineral Admixtures

    OpenAIRE

    Jae-Im Park; Kwang-Myong Lee; Soon-Oh Kwon; Su-Ho Bae; Sang-Hwa Jung; Sung-Won Yoo

    2016-01-01

    The diffusion coefficient for chloride ions and the diffusion decay coefficient for chloride ions are essential variables for a service life evaluation of concrete structures. They are influenced by water-binder ratio, exposure condition, curing temperature, cement type, and the type and use of mineral admixture. Mineral admixtures such as ground granulated blast furnace slag, fly ash, and silica fume have been increasingly used to improve resistance against chloride ions penetration in concr...

  2. Study of the mapping mechanism of ferroelectric domains with the scanning force microscope; Untersuchung der Abbildungsmechanismen ferroelektrischer Domaenen mit dem Rasterkraftmikroskop

    Energy Technology Data Exchange (ETDEWEB)

    Jungk, T.

    2006-12-15

    The piezo-force microscopy (PFM) allows the mapping of ferroelectric domains until the nanometer range. In spite of its simple function principle it was hitherto not completely understood. In ordser to develop the PFM further to a quantitative analysis method its methodical aspects were analyzed. It was shown that the fundamental mapping mechanism is based on the inverse piezo-effect. Different artefacts to be found in the literature could therefore be reduced to a measurement background. Furthermore the influence of the electrode geometry was analyzed. The width of doamin walls was systematically measured and simulated with a mode, whereby a maximal resolution of 17 nm was reached. By the development of a correction procedure for the exact detection of the forces acting on the spring-beam the lateral signals measured on domain walls could by newly interpreted. So the ''Lateral Electrostatic Force Microscopy'' was developed.

  3. A Novel Admixture-Based Pharmacogenetic Approach to Refine Warfarin Dosing in Caribbean Hispanics.

    Directory of Open Access Journals (Sweden)

    Jorge Duconge

    Full Text Available This study is aimed at developing a novel admixture-adjusted pharmacogenomic approach to individually refine warfarin dosing in Caribbean Hispanic patients.A multiple linear regression analysis of effective warfarin doses versus relevant genotypes, admixture, clinical and demographic factors was performed in 255 patients and further validated externally in another cohort of 55 individuals.The admixture-adjusted, genotype-guided warfarin dosing refinement algorithm developed in Caribbean Hispanics showed better predictability (R2 = 0.70, MAE = 0.72mg/day than a clinical algorithm that excluded genotypes and admixture (R2 = 0.60, MAE = 0.99mg/day, and outperformed two prior pharmacogenetic algorithms in predicting effective dose in this population. For patients at the highest risk of adverse events, 45.5% of the dose predictions using the developed pharmacogenetic model resulted in ideal dose as compared with only 29% when using the clinical non-genetic algorithm (p<0.001. The admixture-driven pharmacogenetic algorithm predicted 58% of warfarin dose variance when externally validated in 55 individuals from an independent validation cohort (MAE = 0.89 mg/day, 24% mean bias.Results supported our rationale to incorporate individual's genotypes and unique admixture metrics into pharmacogenetic refinement models in order to increase predictability when expanding them to admixed populations like Caribbean Hispanics.ClinicalTrials.gov NCT01318057.

  4. A slide-rule for assessment of venous admixture.

    Science.gov (United States)

    Zetterström, H

    1989-04-01

    Determination of venous admixture (physiological shunt, Qva/Qt) requires analysis of both arterial and mixed venous blood. When a pulmonary arterial catheter is not in use, the pulmonary oxygenating capacity may be assessed from arterial blood gas data, the fraction of inspired oxygen (FIO2) and an assumed value of the arterial-mixed venous oxygen content difference. To facilitate this process, a slide-rule based on the "virtual shunt" concept is presented. It permits rapid assessment of Qva/Qt from known values of arterial oxygen tension (PaO2) or saturation (SaO2) and FIO2 and may promote the choice of appropriate FIO2. The limitations of the slide-rule were studied theoretically and its validity was tested by comparing 100 determinations of virtual shunt with the corresponding Qva/Qt values. The slide-rule was found to estimate Qva/Qt more accurately than commonly used oxygenation indices such as the PaO2/FIO2 ratio. PMID:2499154

  5. Research on Development and Performance of Active Admixture

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Comparing with that of low-calcium fly ash (LF) or fly dreg (FD), chemical content of high-calcium fly ash (HF) waves more much. Coarse grain, which existing in HF, would determine soundness more seriously than fine one. Grinding it is a simple method to result this problem. Because of with thiner specific surface and higher CaO content, fine grain exhibits higher activity of hydration than coarse one. Activity of active admixture (AF), which is produced by ways of grinding HF together with calcium carbide sludge (CS), desulfurize gypsum (DG), calcine desulfurize gypsum (CG) and NS (Na2SO4+FeSO4), can catch up with that of grinding blast furnace slag (GBFS) powder with about 400 m2/kg specific surface. AF costs lower than GBFS. 20% cement replaced by the equal amount of AF, compression strength of concrete is similar to that control one, and electrifies coulomb of concrete at 90 day's age reduces to about half of control one.

  6. Influences of a New Admixture MX on Concrete Durability

    Institute of Scientific and Technical Information of China (English)

    MA Baoguo; DONG Rongzhen; ZHU Hongbo; ZHANG Li; ZHONG Kaihong; HE Xingyang; LI Zongjin

    2005-01-01

    The performance of concrete with a new admixture MX was studied by using the freeze-thaw cycle, permeability and chemical attack test. The experimental results show that MX improves the durability of concrete. Within the optimum proportion ranges from 0.1%to 1%,the compressive strength of concrete after freeze-thaw is increased by 20%-50%,and Young's modulus can be increased by 3.76-5.64 times.The strength and weight loss of concrete with 0.4%MX are respectively decreased by 28% and 60% after hydrochloric acid attack.The strength and weight loss of concrete with 0.4% MX are decreased by 5%-20% after sulfuric acid and sodium sulfate attack.The permeability of concrete with 1% MX at 28 days can be decreased by more than 30%. The investigation of the negative temperature property of MX and analysis on concrete composition and microstructure by MIP reveal that the heat conduction is resisted and the freezing procedure of solution in concrete pore is retarded due to the adding of MX. Moreover,the pore structure of concrete with MX is improved, thus improving the durability. Based on this study, a resistance model of MX to block the heat and mass transference was proposed, and the mechanism of durability improvement of concrete with MX was explained.

  7. MRI Scans

    Science.gov (United States)

    Magnetic resonance imaging (MRI) uses a large magnet and radio waves to look at organs and structures inside your body. Health care professionals use MRI scans to diagnose a variety of conditions, from ...

  8. CT scan

    Science.gov (United States)

    ... come from a CT scan. Some people have allergies to contrast dye. Let your doctor know if you have ... vein contains iodine. If you have an iodine allergy, a type of contrast may cause nausea or vomiting , sneezing , itching , or ...

  9. Based on Three-Dimensional Laser Scan Technology of Landslide Topographic Map Creation Research%基于3维激光扫描技术的滑坡体地形图制作研究

    Institute of Scientific and Technical Information of China (English)

    焦学军

    2013-01-01

    采用3维激光扫描技术快速采集滑坡体地形点云信息,并提取滑坡体微地貌信息,为滑坡监测提供基础技术支持。3维激光扫描技术的数据处理主要包括外业数据采集、点云数据配准、地貌数据获取与非地貌点云数据过滤、地形图生成等过程,并着重介绍其工作原理与处理方法。采用3维激光扫描技术能够高效准确实时的监测地质灾害,对预防灾害的发生提供了决策作用。%The point cloud information has been rapid collected by three -dimensional laser scan technology , and the landslide micro-photography information has been extracted from it .This informationprovides the infrastructure technology support for the landslide mo-nitoring.The data processing by three -dimensional laser scan technology mainly includes:field data collection , point cloud data reg-istration, geomorphology information acquisition ,non-geomorphology data filtration , topographic map creation .This paper emphati-cally introduces the working principle and processing method of three-dimensional laser scan technology .The monitoring of geological hazard is high efficient , accurate and real -time though three-dimensional laser scan technology .This method provides decision -making function for disaster prevention .

  10. Stability investigation of total parenteral nutrition admixture prepared in a hospital pharmacy

    Directory of Open Access Journals (Sweden)

    Mirković Dušica

    2008-01-01

    Full Text Available Background/Aim. In the cases when nutrition of patients can not be orally nor enterally performed, parenteral nutrition is a method of the therapy that provides more successful and rapid recovery. In that way, hospitalization can be significantly shorter, healing costs reduced and mortality minimized. Total parenteral nutrition (TPN admixtures are the most complex systems which contain amino acids, carbohydrates, lipid emulsion, macroelectrolytes (Na+, K+, Ca2+, Mg2+, Cl-, SO42-, PO43-, oligoelements, hydro- and liposoluble vitamines, heparin, insulin and water. Concerning the mentioned complexity, special attention should be payed to physicochemical and microbiological stability of a mixture, because of interactions among components, that can be very hard to analyze. The aim of this study was to investigate the problem of stability of TPN admixtures prepared in a hospital pharmacy. Methods. Admixture TPN was aseptically prepared in laminar air - flow environment on the basis of the specified order in supplementing components and additives to basic solutions. Solutions were kept in sterile multicompartment ethylene-vinyl-acetate bags. After preparation and slow homogenization, TPN admixtures were submitted to physicochemical and microbiological stability analyses in various period of time. The assessment of physical stability of TPN admixture was done on the basis of visual inspection, determination of pH value and measuring of particle size. The investigation of sterility and pyrogenic test were performed according to Ph. Yug. V regulations. Results. Physico-chemical and microbiological analyses were applied and no significant changes in visual sense, pH value and droplet size stability of the TPN admixture were observed during the period of 60 hours. The lipid droplets were smaller in size than 5 μm, that is the most common pharmacopoeia requirement. Conclusion. The results of our study confirmed that a TPN admixture prepared in a hospital

  11. Porosity Parameters Of Cement Stone Containing Chemical Admixtures Of Different Purpose

    Directory of Open Access Journals (Sweden)

    Lukas Venčkauskas

    2013-12-01

    Full Text Available The conducted research has established a complex influenceand the impact of separate chemical admixtures of differentpurpose on the parameters of the porosity of hardened cementpaste such as open and closed porosity, the average size of poresand the rates of pore inequality. According to the parametersof the porosity of hardened cement paste, on the basis of A. E.Sheikin’s methodology, the number of freezing-thawing cycleswas predicted. This research used plasticizing, viscosity modifyingand antifoaming admixtures. It has been found that, when theamount of plasticizing admixture in cement paste (W/C–0.45 isconstant and makes 1.1% of the cement mass, and the amountof viscosity modifying and antifoaming the admixture increasesfrom 0.1 to 0.6% and from 0.05 to 0.3% respectively, the openporosity of hardened cement paste varies between 30.21% and31.06%, while closed porosity varies between 5.39% and 6.22%.When the amount of the plasticizing admixture in cement paste(W/C–0.45 exceeds 1.1% of the cement mass, the open porosityof hardened cement paste increases by 1.4 times and closedporosity decreases by 2.5 times. While adding 0.1% of the viscositymodifying admixture to cement paste, the open porosityof hardened cement paste is increased by 1.5 times and closedporosity decreases by 2.4 times. The amount of 0.05% of thecement mass of the antifoaming admixture results in the increasedopen porosity of hardened cement paste by 1.5 times and reducedclosed porosity by 3.5 times.

  12. Stability of total nutrient admixtures in a dual-chamber flexible container.

    Science.gov (United States)

    Tripp, M G; Menon, S K; Mikrut, B A

    1990-11-01

    The stability of total nutrient admixtures (TNAs) prepared from dextrose and amino acid injections commercially packaged in a dual-chamber container and a safflower-soybean oil fat emulsion was studied. The admixtures studied were divided into two groups. Group 1 admixtures represented 14 combinations of Aminosyn II, dextrose, and Liposyn II. Group 2 admixtures represented 10 combinations of Aminosyn II with Electrolytes, dextrose, and Liposyn II. Amino acid concentrations of 7, 8.5, and 10%, dextrose concentrations of 10, 20, 40, and 50%, and 10 and 20% fat emulsion were used. After the amino acid and dextrose injections were mixed in their original container (Nutrimix, Abbott Laboratories), the fat emulsion was added. One of two combinations of electrolytes and trace metals was then added. Multivitamins were added to each TNA just before 24-hour storage at room temperature (25 +/- 4 degrees C). Admixtures were tested initially and at the conclusion of storage periods of 24 hours at room temperature or nine days at 5 degrees C followed by 24 hours at room temperature. Measurements of pH, emulsion particle size, and weight percent of oil particles larger than 5 microns in diameter (HIAC) were made after visual inspection of each admixture. In selected admixtures, concentrations of individual amino acids and dextrose were determined by chromatographic techniques initially and at the conclusion of storage. The TNAs retained a uniform milk-like appearance throughout both storage periods. The pH values, particle size, HIAC measurements, and amino acid and dextrose concentrations remained essentially unchanged.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2126163

  13. Extensive Admixture and Selective Pressure Across the Sahel Belt.

    Science.gov (United States)

    Triska, Petr; Soares, Pedro; Patin, Etienne; Fernandes, Veronica; Cerny, Viktor; Pereira, Luisa

    2015-11-26

    Genome-wide studies of African populations have the potential to reveal powerful insights into the evolution of our species, as these diverse populations have been exposed to intense selective pressures imposed by infectious diseases, diet, and environmental factors. Within Africa, the Sahel Belt extensively overlaps the geographical center of several endemic infections such as malaria, trypanosomiasis, meningitis, and hemorrhagic fevers. We screened 2.5 million single nucleotide polymorphisms in 161 individuals from 13 Sahelian populations, which together with published data cover Western, Central, and Eastern Sahel, and include both nomadic and sedentary groups. We confirmed the role of this Belt as a main corridor for human migrations across the continent. Strong admixture was observed in both Central and Eastern Sahelian populations, with North Africans and Near Eastern/Arabians, respectively, but it was inexistent in Western Sahelian populations. Genome-wide local ancestry inference in admixed Sahelian populations revealed several candidate regions that were significantly enriched for non-autochthonous haplotypes, and many showed to be under positive selection. The DARC gene region in Arabs and Nubians was enriched for African ancestry, whereas the RAB3GAP1/LCT/MCM6 region in Oromo, the TAS2R gene family in Fulani, and the ALMS1/NAT8 in Turkana and Samburu were enriched for non-African ancestry. Signals of positive selection varied in terms of geographic amplitude. Some genomic regions were selected across the Belt, the most striking example being the malaria-related DARC gene. Others were Western-specific (oxytocin, calcium, and heart pathways), Eastern-specific (lipid pathways), or even population-restricted (TAS2R genes in Fulani, which may reflect sexual selection).

  14. Scan Statistics

    CERN Document Server

    Glaz, Joseph

    2009-01-01

    Suitable for graduate students and researchers in applied probability and statistics, as well as for scientists in biology, computer science, pharmaceutical science and medicine, this title brings together a collection of chapters illustrating the depth and diversity of theory, methods and applications in the area of scan statistics.

  15. ADSORPTION OF CHROMIUM (VI FROM AQUEOUS SOLUTIONS BY DIFFERENT ADMIXTURES – A BATCH EQUILIBRIUM TEST STUDY

    Directory of Open Access Journals (Sweden)

    K. SHIVA PRASHANTH KUMAR

    2014-08-01

    Full Text Available Wide variety of inorganic compounds such as nutrients and trace metals, organic chemicals, radioactive contaminants and pathogens are commonly present as contaminants in the groundwater. Migration of contaminants in soil involves important mechanisms such as molecular diffusion, dispersion under physical processes, adsorption, precipitation and oxidation - reduction under chemical processes and biodegradation under biological process. Cr (VI is a major and dangerous contaminant as per the ground water is concerned. There are numerous research work carried out with concentrated efforts by the researchers towards removal of Cr (VI contaminant from aqueous solutions. There are few studies relevant to Cr (VI removal with respect to utilization of low cost admixtures and also soil type. In the present study, different low cost admixtures like rice husk (RH, shredded tyre (ST and fly ash (FA are used to understand the performance in removal of Cr (VI from aqueous solution and also two different soil types are used along with the admixture. The results are discussed in terms of sorption capacity and performance of individual admixture and combination of admixture with soil in removal of contaminant. The fly ash, rice husk and shredded tyre admixtures are used and the results revealed that the shredded tyre showed higher performance in removal of contaminant concentration. Also, the soil which has more fine particle content (size<0.075 mm IS sieve showed reasonable reduction in concentration of contaminant at the lower levels of contaminant initial concentration. The sorption capacity results of Cr (VI contaminant, treated with various admixtures are further validated with the published work of other investigators. The shredded tyre (ST showed more adsorption capacity, i.e., 3.283 mg/g at pH of 4.8. For other admixtures, adsorption capacity value is varying in the range of 0.07 mg/g to 1.7 mg/g. Only in case of activated alumina and modified saw dust

  16. The Mechanism of the Eeffect of Mineral Admixtures on the Expansion of Aalkali-silica Reaction

    Institute of Scientific and Technical Information of China (English)

    WANG Aiqin; Niu Jishou; ZHANG Chengzhi

    2008-01-01

    On the base of the influence rule of silica fume, slag and fly ash on alkali-silica reaction under the condition of 70℃, the mechanism of the effect of mineral admixtures on alkali-silica reaction is studied further in the paper. The results show that the effects of mineral admixtures on alkali-silica reaction are mainly chemistry effect and surface physichemistry effect. Under suitable condition, the chemistry effect may make alkali-silica reaction to be inhibited effectively, but the physichemistry effect only make alkali-silica reaction to be delayed. The chemistry effect and the physichemistry effect of minerals admixture are relative to the content of Ca(OH)2 in system. Under the condition that there is a large quantity of Ca(OH)2, mineral admixture cannot inhibit alkali-silica reaction effectively. Only when Ca(OH)2 in the system is very less, it is possible that mineral admixture inhibits alkali-silica reaction effectively.

  17. Efficacy of Industrial waste admixture in Improving Engineering Performance of Clayey soil – A quantitative study

    Directory of Open Access Journals (Sweden)

    Kiran B. Biradar

    2014-09-01

    Full Text Available Infrastructure and industrialization serves as a back bone for a country’s economy. However due to rapid industrialization there exist a problem in the form of waste accumulation and subsequent problems due to their disposal & effects of waste. In infrastructure development, roads play a major role. In general pavement construction needs bulk quantities of good soil keeping in view of the service and longevity aspects. Due to limitation in availability of good soil, often the cost of projects escalates. An ideal solution lies for reducing project cost, increasing longevity and reduce accumulation of waste shall be through utilization of industrial waste combined with weak soil for pavement construction. Few types of waste materials namely crusher dust, fly ash and Steel slag waste are popular as admixtures in improving weak soils. This paper discusses the performance of admixtures in improving weak soil through mechanical stabilization. Results of tests on index and engineering properties of mechanically stabilized clayey soil with industrial waste admixtures namely, crusher dust, fly ash and steel slag are presented for different admixture contents and test conditions. A comparison is made based on improved performance. It is observed that Steel slag is proven to be effective over other types. From the results optimum content of admixture for a given improvement is suggested.

  18. Mechanical Characteristics of Hardened Concrete with Different Mineral Admixtures: A Review

    Science.gov (United States)

    2014-01-01

    The available literature identifies that the addition of mineral admixture as partial replacement of cement improves the microstructure of the concrete (i.e., porosity and pore size distribution) as well as increasing the mechanical characteristics such as drying shrinkage and creep, compressive strength, tensile strength, flexural strength, and modulus of elasticity; however, no single document is available in which review and comparison of the influence of the addition of these mineral admixtures on the mechanical characteristics of the hardened pozzolanic concretes are presented. In this paper, based on the reported results in the literature, mechanical characteristics of hardened concrete partially containing mineral admixtures including fly ash (FA), silica fume (SF), ground granulated blast furnace slag (GGBS), metakaolin (MK), and rice husk ash (RHA) are discussed and it is concluded that the content and particle size of mineral admixture are the parameters which significantly influence the mechanical properties of concrete. All mineral admixtures enhance the mechanical properties of concrete except FA and GGBS which do not show a significant effect on the strength of concrete at 28 days; however, gain in strength at later ages is considerable. Moreover, the comparison of the mechanical characteristics of different pozzolanic concretes suggests that RHA and SF are competitive. PMID:24688443

  19. A deterministic model of admixture and genetic introgression: the case of Neanderthal and Cro-Magnon.

    Science.gov (United States)

    Forhan, Gerald; Martiel, Jean-Louis; Blum, Michael G B

    2008-11-01

    There is an ongoing debate in the field of human evolution about the possible contribution of Neanderthals to the modern human gene pool. To study how the Neanderthal private alleles may have spread over the genes of Homo sapiens, we propose a deterministic model based on recursive equations and ordinary differential equations. If the Neanderthal population was large compared to the Homo sapiens population at the beginning of the contact period, we show that genetic introgression should have been fast and complete meaning that most of the Neanderthal private alleles should be found in the modern human gene pool in case of ancient admixture. In order to test/reject ancient admixture from genome-wide data, we incorporate the model of genetic introgression into a statistical hypothesis-testing framework. We show that the power to reject ancient admixture increases as the ratio, at the time of putative admixture, of the population size of Homo sapiens over that of Neanderthal decreases. We find that the power to reject ancient admixture might be particularly low if the population size of Homo sapiens was comparable to the Neanderthal population size. PMID:18768141

  20. Iron, copper, zinc and bromine mapping in cirrhotic liver slices from patients with hemochromatosis studied by microscopic synchrotron radiation X-ray fluorescence analysis in continuous scanning mode

    Energy Technology Data Exchange (ETDEWEB)

    Osterode, W. [Medizinische Universitaet Wien, Univ. Klinik fuer Innere Medizin IV, Klinische Abteilung fuer Arbeitsmedizin, Waehringer Guertel 18-20, A-1090 Wien (Austria)], E-mail: wolf.osterode@meduniwien.ac.at; Falkenberg, G. [Hamburger Synchrotronstrahlungslabor HASYLAB, Deutsches Elektronen-Synchrotron DESY (Germany); Hoeftberger, R. [Medizinische Universitaet Wien, Klinisches Institut fuer Neurologie (Austria); Wrba, F. [Medizinische Universitaet Wien, Klinisches Institut fuer Klinische Pathologie (Austria)

    2007-07-15

    Iron (Fe) and copper (Cu) are essential metals in physiological cell metabolism. While Fe is easy to determine biochemically in histological slices, Cu and zinc (Zn) distribution is frequently critical in confirming the presence of an overload in disturbed Fe/Cu metabolism. To analyze Fe, Cu and Zn in a near histological resolution, energy dispersive microscopic synchrotron radiation X-ray fluorescence was applied. In normal liver tissue, after fixation and imbedding in paraffin, mean Fe, Cu and Zn concentrations were 152 {+-} 54, 20.1 {+-} 4.3 and 88.919.5 {mu}g/g sample weight, respectively. No substantial, characteristic differences in their distribution were found in the two-dimensional scans. In slices from patients with hemochromatosis mean Fe, Cu and Zn concentrations were 1102 {+-} 539, 35.9 {+-} 14.6 and 27.2 {+-} 6.7 {mu}g/g sample weight, respectively. Additionally, a significant decrease in phosphorus and sulphur concentrations existed. An increased Cu around cirrhotic regenerations nodules is mostly associated with a lymphocytic infiltration in this region. Analyzing concentrations of Fe in different regions of the samples show a clear negative dependency between Fe and Cu, Cu and Zn, but a positive one between Fe and Zn. Conclusion: With a focal beam size of 15 {mu}m in diameter a resolution of the elemental distribution was achieved which is widely comparable with stained histological slices (20x light microscope). The analysis of simultaneous determined elements reveals metabolic differences between Fe, Cu and Zn in liver tissue from patients with hemochromatosis.

  1. Iron, copper, zinc and bromine mapping in cirrhotic liver slices from patients with hemochromatosis studied by microscopic synchrotron radiation X-ray fluorescence analysis in continuous scanning mode

    Science.gov (United States)

    Osterode, W.; Falkenberg, G.; Höftberger, R.; Wrba, F.

    2007-07-01

    Iron (Fe) and copper (Cu) are essential metals in physiological cell metabolism. While Fe is easy to determine biochemically in histological slices, Cu and zinc (Zn) distribution is frequently critical in confirming the presence of an overload in disturbed Fe/Cu metabolism. To analyze Fe, Cu and Zn in a near histological resolution, energy dispersive microscopic synchrotron radiation X-ray fluorescence was applied. In normal liver tissue, after fixation and imbedding in paraffin, mean Fe, Cu and Zn concentrations were 152 ± 54, 20.1 ± 4.3 and 88.919.5 μg/g sample weight, respectively. No substantial, characteristic differences in their distribution were found in the two-dimensional scans. In slices from patients with hemochromatosis mean Fe, Cu and Zn concentrations were 1102 ± 539, 35.9 ± 14.6 and 27.2 ± 6.7 μg/g sample weight, respectively. Additionally, a significant decrease in phosphorus and sulphur concentrations existed. An increased Cu around cirrhotic regenerations nodules is mostly associated with a lymphocytic infiltration in this region. Analyzing concentrations of Fe in different regions of the samples show a clear negative dependency between Fe and Cu, Cu and Zn, but a positive one between Fe and Zn. Conclusion: With a focal beam size of 15 μm in diameter a resolution of the elemental distribution was achieved which is widely comparable with stained histological slices (20× light microscope). The analysis of simultaneous determined elements reveals metabolic differences between Fe, Cu and Zn in liver tissue from patients with hemochromatosis.

  2. Genetic admixture and lineage separation in a southern Andean plant

    Science.gov (United States)

    Morello, Santiago; Sede, Silvana M.

    2016-01-01

    varieties of E. alpina: var. alpina is more closely related to E. rubra and other species than to its own counterpart E. alpina var. carmelitana. Geometric morphometrics analysis (Elliptic Fourier descriptors) revealed significant differences in leaf shape between varieties. We found that diversity in Escallonia species analyzed here is geographically structured and deep divergence between varieties of E. alpina could be associated to ancient evolutionary events like orogeny. Admixture in southern populations could be the result of hybridization at the margins of the parental species’ distribution range. PMID:27179539

  3. Perineal scanning.

    Science.gov (United States)

    Jeanty, P; d'Alton, M; Romero, R; Hobbins, J C

    1986-10-01

    Although various techniques have been described to aid in the ultrasound diagnosis of placenta previa and incompetent cervix, these maneuvers depend on the precise identification of the internal cervical os, a feat which is notoriously difficult to accomplish consistently. In an attempt to get a closer view of the cervix we tried another approach. This simple technique of perineal scanning has the potential to help considerably with these problems. PMID:3530265

  4. On the integration of Airborne full-waveform laser scanning and optical imagery for Site Detection and Mapping: Monteserico study case

    Science.gov (United States)

    Coluzzi, R.; Guariglia, A.; Lacovara, B.; Lasaponara, R.; Masini, N.

    2009-04-01

    This paper analyses the capability of airborne LiDAR derived data in the recognition of archaeological marks. It also evaluates the benefits to integrate them with aerial photos and very high resolution satellite imagery. The selected test site is Monteserico, a medieval village located on a pastureland hill in the North East of Basilicata (Southern Italy). The site, attested by documentary sources beginning from the 12th century, was discovered by aerial survey in 1996 [1] and investigated in 2005 by using QuickBird imagery [2]. The only architectural evidence is a castle, built on the western top of the hill; whereas on the southern side, earthenware, pottery and crumbling building materials, related to the medieval settlement, could be observed. From a geological point of view, the stratigraphic sequence is composed of Subappennine Clays, Monte Marano sands and Irsina conglomerates. Sporadic herbaceous plants grow over the investigated area. For the purpose of this study, a full-waveform laser scanning with a 240.000 Hz frequency was used. The average point density value of dataset is about 30 points/m2. The final product is a 0.30 m Digital Surface Models (DSMs) accurately modelled. To derive the DSM the point cloud of the ALS was filtered and then classified by applying appropriate algorithms. In this way surface relief and archaeological features were surveyed with great detail. The DSM was compared with other remote sensing data source such as oblique and nadiral aerial photos and QuickBird imagery, acquired in different time. In this way it was possible to evaluate, compare each other and overlay the archaeological features recorded from each data source (aerial, satellite and lidar). Lidar data showed some interesting results. In particular, they allowed for identifying and recording differences in height on the ground produced by surface and shallow archaeological remains (the so-called shadow marks). Most of these features are visible also by the optical

  5. Portland cement hydration in the presence of admixtures: black gram pulse and superplasticizer

    Directory of Open Access Journals (Sweden)

    Viveka Nand Dwivedi

    2008-12-01

    Full Text Available Effect of admixtures such as black gram pulse (BGP and sulfonated naphthalene based superplasticizer (SP on the hydration of Portland cement has been studied. The hydration characteristics of OPC in the presence of BGP and SP were studied with the help of non evaporable water content determinations, calorimetric method, Mössbauer spectroscopic and atomic force microscopic techniques. Results have shown that both BGP and SP get adsorbed at the surface of cement and its hydration products. The hydration of Portland cement is retarded in the presence of both the admixtures and nanosize hydration products are formed.

  6. Y-STR diversity and ethnic admixture in White and Mulatto Brazilian population samples

    OpenAIRE

    Luzitano Brandão Ferreira; Celso Teixeira Mendes-Junior; Cláudia Emília Vieira Wiezel; Marcelo Rizzatti Luizon; Aguinaldo Luiz Simões

    2006-01-01

    We investigated 50 Mulatto and 120 White Brazilians for the Y-chromosome short tandem repeat (Y-STR) markers (DYS19, DYS390, DYS391, DYS392 and DYS393) and found 79 different haplotypes in the White and 35 in the Mulatto sample. Admixture estimates based on allele frequencies showed that the admixture of the white sample was 89% European, 6% African and 5% Amerindian while the Mulatto sample was 93% European and 7% African. Results were consistent with historical records of the directional ma...

  7. Y-STR diversity and ethnic admixture in White and Mulatto Brazilian population samples

    Directory of Open Access Journals (Sweden)

    Luzitano Brandão Ferreira

    2006-01-01

    Full Text Available We investigated 50 Mulatto and 120 White Brazilians for the Y-chromosome short tandem repeat (Y-STR markers (DYS19, DYS390, DYS391, DYS392 and DYS393 and found 79 different haplotypes in the White and 35 in the Mulatto sample. Admixture estimates based on allele frequencies showed that the admixture of the white sample was 89% European, 6% African and 5% Amerindian while the Mulatto sample was 93% European and 7% African. Results were consistent with historical records of the directional mating between European males and Amerindian or African females.

  8. Scanning tunneling microscopy II further applications and related scanning techniques

    CERN Document Server

    Güntherodt, Hans-Joachim

    1995-01-01

    Scanning Tunneling Microscopy II, like its predecessor, presents detailed and comprehensive accounts of the basic principles and broad range of applications of STM and related scanning probe techniques. The applications discussed in this volume come predominantly from the fields of electrochemistry and biology. In contrast to those described in STM I, these studies may be performed in air and in liquids. The extensions of the basic technique to map other interactions are described in chapters on scanning force microscopy, magnetic force microscopy, and scanning near-field optical microscopy, together with a survey of other related techniques. Also described here is the use of a scanning proximal probe for surface modification. Together, the two volumes give a comprehensive account of experimental aspects of STM. They provide essential reading and reference material for all students and researchers involved in this field. In this second edition the text has been updated and new methods are discussed.

  9. Scanning tunneling microscopy II further applications and related scanning techniques

    CERN Document Server

    Güntherodt, Hans-Joachim

    1992-01-01

    Scanning Tunneling Microscopy II, like its predecessor, presents detailed and comprehensive accounts of the basic principles and broad range of applications of STM and related scanning probe techniques. The applications discussed in this volume come predominantly from the fields of electrochemistry and biology. In contrast to those described in Vol. I, these sudies may be performed in air and in liquids. The extensions of the basic technique to map other interactions are described inchapters on scanning force microscopy, magnetic force microscopy, scanning near-field optical microscopy, together with a survey of other related techniques. Also described here is the use of a scanning proximal probe for surface modification. Togehter, the two volumes give a comprehensive account of experimental aspcets of STM. They provide essentialreading and reference material for all students and researchers involvedin this field.

  10. COMPUTER DESIGN OF PROCESSES OF MIGRATION OF ADMIXTURES IN NATURAL WATERS STREAMS

    OpenAIRE

    Savenko, V.; Bondarenko, L.

    2006-01-01

    In work new complex approach of research of processes of transfer of harmful admixtures is offered in natural streams, which is founded on the use of methods of three-dimensional computer design. Basic mathematical equalizations, description of software products, examples of numeral calculations, are resulted on the basis of the offered method

  11. Stabilization of Fine Sand with Ceramic Tiles Waste as Admixture for Construction of Embankment

    Directory of Open Access Journals (Sweden)

    Kapil Panwar

    2016-08-01

    Full Text Available This paper deals with the stabilization of fine sand with Ceramic Tiles waste as admixture. As the fine sand has very low bearing capacity and compressive strength along with nil cohesion, thus the construction of any structure on fine soil required stabilization. This study discusses the possibility of fine sand stabilization using Ceramic Tile Waste as admixture. Present work has been taken up by addition of 4.75 mm sieve passed and 2.36 mm sieve retained Ceramic Tile Waste as admixture. The varying percentage 2%, 4%, 8% and 12% of ceramic tile waste were mixed with fine sand of different densities 1.50 gm/cc, 1.55 gm/cc and 1.58 gm/cc. All the Direct Shear Tests were conducted at different mix compositions of ceramic tile waste and fine sand of different dry densities as arrived from Standard Proctor Test. Falling-Head Permeability Tests were also performed on different mix compositions. On the basis of the experiments performed, it is determined that the stabilization of fine sand using ceramic tile waste as admixture improves the strength characteristics of the fine sand so that it becomes usable as construction of embankment.

  12. The scale and nature of Viking settlement in Ireland from Y-chromosome admixture analysis.

    Science.gov (United States)

    McEvoy, Brian; Brady, Claire; Moore, Laoise T; Bradley, Daniel G

    2006-12-01

    The Vikings (or Norse) played a prominent role in Irish history but, despite this, their genetic legacy in Ireland, which may provide insights into the nature and scale of their immigration, is largely unexplored. Irish surnames, some of which are thought to have Norse roots, are paternally inherited in a similar manner to Y-chromosomes. The correspondence of Scandinavian patrilineal ancestry in a cohort of Irish men bearing surnames of putative Norse origin was examined using both slow mutating unique event polymorphisms and relatively rapidly changing short tandem repeat Y-chromosome markers. Irish and Scandinavian admixture proportions were explored for both systems using six different admixture estimators, allowing a parallel investigation of the impact of method and marker type in Y-chromosome admixture analysis. Admixture proportion estimates in the putative Norse surname group were highly consistent and detected little trace of Scandinavian ancestry. In addition, there is scant evidence of Scandinavian Y-chromosome introgression in a general Irish population sample. Although conclusions are largely dependent on the accurate identification of Norse surnames, the findings are consistent with a relatively small number of Norse settlers (and descendents) migrating to Ireland during the Viking period (ca. AD 800-1200) suggesting that Norse colonial settlements might have been largely composed of indigenous Irish. This observation adds to previous genetic studies that point to a flexible Viking settlement approach across North Atlantic Europe.

  13. Recycling of tailings from Korea Molybdenum Corporation as admixture for high-fluidity concrete.

    Science.gov (United States)

    Jung, Moon Young; Choi, Yun Wang; Jeong, Jae Gwon

    2011-01-01

    The main objective of this study is to develop an eco-friendly and a large recycling technique of flotation Tailings from korea (TK) from metal mines as construction materials such as admixtures for high-fluidity concrete (HFC). TK used in this study was obtained from the Korea Molybdenum Corporation in operation. TK was used as the alternative material to adjust flowability and viscosity of HFC in the form of powder agent which enables adjustment of concrete compressive strength. In this study, we have performed concrete rheological tests and concrete flowability tests to obtain the quality characteristics of TK for using as the admixture in producing HFC. The results indicated that the adequate mix ratio of cement to TK should be 8:2 (vol%). It is more effective to use the TK as admixture to control flowability, viscosity and strength of HFC than the normal concrete. It was found that TK could be recycled construction materials in bulk such as admixture for HFC, in terms of the economic and eco-friendly aspects. PMID:21113645

  14. What Causes Birth Order-Intelligence Patterns? The Admixture Hypothesis, Revived.

    Science.gov (United States)

    Rodgers, Joseph Lee

    2001-01-01

    Describes why birth order interests both parents and researchers, discussing what really causes apparent birth order effects on intelligence, examining problems with using cross-sectional intelligence data, and noting how to move beyond cross-sectional inferences. Explains the admixture hypothesis, which finds that family size is much more…

  15. Chemical Stability of Admixtures Combining Ziconotide with Morphine or Hydromorphone During Simul ated Intrathecal Administration.

    Science.gov (United States)

    Shields, David; Montenegro, Rick; Ragusa, Matthew

    2005-10-01

    Objective.  To determine the stability of admixtures combining ziconotide with morphine or hydromorphone under simulated intrathecal infusions. Materials and Methods.  Admixtures of ziconotide (25 µg/mL) with morphine or hydromorphone (both at 35 mg/mL) were stored in Medtronic SynchroMed® II pumps at 37°C, and in control vials at 37°C and 5°C. Drug concentrations were determined using high-performance liquid chromatography. Results.  The ziconotide pump concentration with morphine declined to 79% of initial in 17 days, and to 88% of initial after 25 days with hydromorphone. Ziconotide concentrations in control vials stored at 37°C displayed similar rates of decay, but vials stored at 5°C exhibited no ziconotide loss. A statistical evaluation of the two combinations shows ziconotide-hydromorphone retaining 80% stability for 40 days (extrapolated), compared to 15 days for ziconotide-morphine. Morphine and hydromorphone were stable in the presence of ziconotide under all conditions. Conclusions.  Ziconotide-hydromorphone admixtures were more stable than ziconotide-morphine admixtures. PMID:22151554

  16. Diffusion Decay Coefficient for Chloride Ions of Concrete Containing Mineral Admixtures

    Directory of Open Access Journals (Sweden)

    Jae-Im Park

    2016-01-01

    Full Text Available The diffusion coefficient for chloride ions and the diffusion decay coefficient for chloride ions are essential variables for a service life evaluation of concrete structures. They are influenced by water-binder ratio, exposure condition, curing temperature, cement type, and the type and use of mineral admixture. Mineral admixtures such as ground granulated blast furnace slag, fly ash, and silica fume have been increasingly used to improve resistance against chloride ions penetration in concrete structures built in an offshore environment. However, there is not enough measured data to identify the statistical properties of diffusion decay coefficient for chloride ions in concrete using mineral admixtures. This paper is aimed at evaluating the diffusion decay coefficient for chloride ions of concrete using ordinary Portland cement or blended cement. NT BUILD 492 method, an electrophoresis experiment, was used to measure the diffusion coefficient for chloride ions with ages. It was revealed from the test results that the diffusion decay coefficient for chloride ions was significantly influenced by W/B and the replacement ratio of mineral admixtures.

  17. Population admixture, biological invasions and the balance between local adaptation and inbreeding depression

    NARCIS (Netherlands)

    Verhoeven, K.J.F.; Macel, M.; Wolfe, L.M.; Biere, A.

    2011-01-01

    When previously isolated populations meet and mix, the resulting admixed population can benefit from several genetic advantages, including increased genetic variation, the creation of novel genotypes and the masking of deleterious mutations. These admixture benefits are thought to play an important

  18. Zinc content of commercial diluents widely used in drug admixtures prepared for intravenous infusion.

    Science.gov (United States)

    Desai, Narendra R; Shah, Syed M; Koczone, Julianna; Vencl-Joncic, Maja; Sisto, Christopher; Ludwig, Stephen A

    2007-01-01

    During ongoing quality improvement efforts with two Wyeth parenteral products, Protonix and Zosyn, we noted that dosing solutions prepared from the products yielded inconsistent results on the United States Pharmacopeia Chapter 788 test for subvisible particulates. This manuscript discusses variables that have a direct impact on intravenous products meeting compendial monograph specifications under conditions that are encountered in the clinical setting. The rubber stoppers of vials used for parenteral products, different parts of commercial admixture bags, and the tubing of the administration sets and devices contain residual amounts of metal ions, plasticizers, and other additives incorparated for specific functions. The transition metal ions, including zinc and copper, may leach into drug products during manufacture and during storage of dosing admixture bags prepared for infusion in hospital pharmacies or clinics. The metal ions may compromise the quality of the infusion admixture through catalytic drug degradation and/or generation of undesirable metal ion complexes, which may convert soluble drug molecules into insoluble particulates. To preserve the quality of the drug product, it is essential that metal ion leachables be controlled proactively during manufacture of the drug product; knowledge of metal ion contents in the commercial diluents use for reconstitution, admixture preparation, and flushing of the administration lines is also critical. PMID:23969523

  19. Effects of Admixtures on the Properties of Corn Cob Ash Cement Concrete

    Directory of Open Access Journals (Sweden)

    Akeem Ayinde RAHEEM

    2010-12-01

    Full Text Available The study investigated the effects of admixtures on the properties of corn cob ash (CCA cement concrete. The workability and compressive strength of CCA cement concrete incorporated with accelerator, plasticizer and water reducing and retarding were carried out. The dosage of admixture incorporated was: 0.124litre per 15.55kg of cementitious material based on the recommendation by BS EN 934-2.The results revealed that admixtures generally improve the workability of corn cob ash cement concrete. The compressive strength obtained at 28th day for concrete without admixture (The Control was 29.82N/mm2, while for concrete with accelerator, plasticizer, and water reducing and retarding it was 32.80 N/mm2, 38.51 N/mm2 and 34.09 N/mm2 respectively. These results showed that CCA cement concrete incorporated with accelerator achieved greater strength at early ages. With plasticizer, it achieved very high strength at both young and old ages; while with water reducing and retarding it achieved greater strength at old ages alone.

  20. The Role of Recent Admixture in Forming the Contemporary West Eurasian Genomic Landscape

    Science.gov (United States)

    Busby, George B.J.; Hellenthal, Garrett; Montinaro, Francesco; Tofanelli, Sergio; Bulayeva, Kazima; Rudan, Igor; Zemunik, Tatijana; Hayward, Caroline; Toncheva, Draga; Karachanak-Yankova, Sena; Nesheva, Desislava; Anagnostou, Paolo; Cali, Francesco; Brisighelli, Francesca; Romano, Valentino; Lefranc, Gerard; Buresi, Catherine; Ben Chibani, Jemni; Haj-Khelil, Amel; Denden, Sabri; Ploski, Rafal; Krajewski, Pawel; Hervig, Tor; Moen, Torolf; Herrera, Rene J.; Wilson, James F.; Myers, Simon; Capelli, Cristian

    2015-01-01

    Summary Over the past few years, studies of DNA isolated from human fossils and archaeological remains have generated considerable novel insight into the history of our species. Several landmark papers have described the genomes of ancient humans across West Eurasia, demonstrating the presence of large-scale, dynamic population movements over the last 10,000 years, such that ancestry across present-day populations is likely to be a mixture of several ancient groups [1, 2, 3, 4, 5, 6, 7]. While these efforts are bringing the details of West Eurasian prehistory into increasing focus, studies aimed at understanding the processes behind the generation of the current West Eurasian genetic landscape have been limited by the number of populations sampled or have been either too regional or global in their outlook [8, 9, 10, 11]. Here, using recently described haplotype-based techniques [11], we present the results of a systematic survey of recent admixture history across Western Eurasia and show that admixture is a universal property across almost all groups. Admixture in all regions except North Western Europe involved the influx of genetic material from outside of West Eurasia, which we date to specific time periods. Within Northern, Western, and Central Europe, admixture tended to occur between local groups during the period 300 to 1200 CE. Comparisons of the genetic profiles of West Eurasians before and after admixture show that population movements within the last 1,500 years are likely to have maintained differentiation among groups. Our analysis provides a timeline of the gene flow events that have generated the contemporary genetic landscape of West Eurasia. PMID:26387712

  1. Genetic analysis of ancestry, admixture and selection in Bolivian and Totonac populations of the New World

    Directory of Open Access Journals (Sweden)

    Watkins W

    2012-05-01

    Full Text Available Abstract Background Populations of the Americas were founded by early migrants from Asia, and some have experienced recent genetic admixture. To better characterize the native and non-native ancestry components in populations from the Americas, we analyzed 815,377 autosomal SNPs, mitochondrial hypervariable segments I and II, and 36 Y-chromosome STRs from 24 Mesoamerican Totonacs and 23 South American Bolivians. Results and Conclusions We analyzed common genomic regions from native Bolivian and Totonac populations to identify 324 highly predictive Native American ancestry informative markers (AIMs. As few as 40–50 of these AIMs perform nearly as well as large panels of random genome-wide SNPs for predicting and estimating Native American ancestry and admixture levels. These AIMs have greater New World vs. Old World specificity than previous AIMs sets. We identify highly-divergent New World SNPs that coincide with high-frequency haplotypes found at similar frequencies in all populations examined, including the HGDP Pima, Maya, Colombian, Karitiana, and Surui American populations. Some of these regions are potential candidates for positive selection. European admixture in the Bolivian sample is approximately 12%, though individual estimates range from 0–48%. We estimate that the admixture occurred ~360–384 years ago. Little evidence of European or African admixture was found in Totonac individuals. Bolivians with pre-Columbian mtDNA and Y-chromosome haplogroups had 5–30% autosomal European ancestry, demonstrating the limitations of Y-chromosome and mtDNA haplogroups and the need for autosomal ancestry informative markers for assessing ancestry in admixed populations.

  2. 基于扫描匹配预处理的即时定位与地图创建%Scan matching preprocess for simultaneous localization and mapping

    Institute of Scientific and Technical Information of China (English)

    温安邦; 吴怀宇; 赵季

    2009-01-01

    Simultaneous Localization And Mapping(SLAM) problem and its solution for indoor autonomous mobile robot are ana-lyzed.To improve the accuracy and robustness,a method using preprocess based on scan match for SLAM is proposed.This method can feed SLAM with a priori pose information,and is proved to be valid and practical by analyzing the result of experiment.%研究了室内自主移动机器人的即时定位与地图创建问题.分析了目前解决SLAM问题的方法,提出了基于扫描匹配预处理的即时定位与地图创建,用扫描匹配为SLAM提供机器人先验位姿信息.对实验结果和数据的分析,得出了所提出方法可进一步提高SLAM的精度和鲁棒性.

  3. Effect of high doses of chemical admixtures on the strength development and freeze-thaw durability of portland cement mortar

    Science.gov (United States)

    Korhonen, Charles J.

    This thesis examines the low-temperature strength development of portland cement concrete made with high doses of chemical admixtures dissolved in the mixing water and the possible beneficial effect of these admixtures on that concrete's long-term freeze-thaw durability. The literature shows that high doses of chemical admixtures can protect fresh concrete against freezing and that, under certain conditions, these admixtures can enhance the freeze-thaw durability of concrete. The challenge is that there are no acceptance standards in the U.S. that allow chemicals to be used to protect concrete against freezing. Also, the perception is that chemicals might somehow harm the concrete. This perception seems to be based on the fact that deicing salts, when applied to concrete pavement, cause roadways to scale away. This study investigated the effect of high doses of commercially available admixtures on fresh concrete while it gained strength at low temperature and on hardened concrete exposed to repeated cycles of freezing and thawing in a moist environment. The reason for studying off-the-shelf admixtures was that these materials are approved for use in concrete; they were already governed by their own set of standards. Four mortars were examined, each with a different cement and water content, when dosed with five commercial admixtures. This allowed the fresh mortar to gain appreciable strength when it was kept at nearly -10C. The admixtures also enhanced the freeze-thaw durability of the mortar, even when it was not air-entrained. Clearly, as the dosage of admixture increased beyond approximately 22% by weight of water, the mortar appeared to be unaffected by up to 700 cycles of freezing and thawing.

  4. Helix Scan: A Scan Design for Diagnosis

    Institute of Scientific and Technical Information of China (English)

    WANG Fei; HU Yu; LI Xiaowei

    2007-01-01

    Scan design is a widely used design-for-testability technique to improve test quality and efficiency. For the scan-designed circuit, test and diagnosis of the scan chain and the circuit is an important process for silicon debug and yield learning. However, conventional scan designs and diagnosis methods abort the subsequent diagnosis process after diagnosing the scan chain if the scan chain is faulty. In this work, we propose a design-for-diagnosis scan strategy called helix scan and a diagnosis algorithm to address this issue. Unlike previous proposed methods, helix scan has the capability to carry on the diagnosis process without losing information when the scan chain is faulty. What is more, it simplifies scan chain diagnosis and achieves high diagnostic resolution as well as accuracy. Experimental results demonstrate the effectiveness of our design.

  5. Public Waters Inventory Maps

    Data.gov (United States)

    Minnesota Department of Natural Resources — This theme is a scanned and rectified version of the Minnesota DNR - Division of Waters "Public Waters Inventory" (PWI) maps. DNR Waters utilizes a small scale...

  6. Anti-chloride permeability and anti-chloride corrodibility of a green high performance concrete admixture in concrete

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yongbao; LIU Xinrong; LIU Dongyan; CHEN Jiangong; HUANG Xiongjun

    2003-01-01

    The effects of green high performance concrete (GHPC) admixture on the anti-chloride permeability and anti- chloride corrodibility of concrete are studied by a series of experiments designed on the basis of the diffusion principle and electrochemical principle. The GHPC admixture consists of fly ash, gangue, slag, red mud, etc., of which the mass fraction of industrial residues is over 96 %. The anti-permeabilities and anti-corrodibilities of the tested GHPC and normal concrete (NC) are evaluated by the Diffusion Coefficients of chloride which was obtained by measuring the concentration of chloride in the tested systems by the voltage difference method. It is found that the adoption of GHPC admixture greatly improves the anti-chloride permeability and anti-chloride corrodibility by modifying the inner structure and contracting the porosity of concrete to the reduce considerably the diffusion rate of chloride. The admixture is desirable regarding its engineering performances as well as economical and environmental interests.

  7. Standard test method for initial screening of corrosion inhibiting admixtures for steel in concrete

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This test method covers a procedure for determining the effects of chemical admixtures on the corrosion of metals in concrete. This test method can be used to evaluate materials intended to inhibit chloride-induced corrosion of steel in concrete. It can also be used to evaluate the corrosivity of admixtures by themselves or in a chloride environment. This test is not applicable for emulsions. 1.2 &solely-SI-units; 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  8. Utilization of black liquor as concrete admixture and set retarder aid

    Directory of Open Access Journals (Sweden)

    Samar A. El-Mekkawi

    2011-04-01

    Full Text Available The utilization of black liquor, produced by the pulp and paper industry in Egypt, as a workability aid and set retarder admixture has been investigated. This approach may help eliminate the environmentally polluting black liquor waste. It also provides a low cost by-product, which can be widely used in the construction industry. The properties of black liquor and its performance on concrete at two different ratios of water to cement have been studied. The results revealed that black liquor from rice straw pulp increases concrete workability, improves compaction, and reduces honeycombing. Moreover, it retards the initial and final set time and enhances uniform compaction. The effect of incorporating small portions of silica fume has been investigated. The ageing effect of this material over a period of one year, to determine its safe storage period, has been studied. Finally, this admixture was found to comply with the relevant Egyptian standards.

  9. Influence of Mineral Admixtures on the Electro-deposition Healing Effect of Concrete Cracks

    Institute of Scientific and Technical Information of China (English)

    CHU Hongqiang; JIANG Linhua; YOU Lushen; XU Ning; SONG Zijian; ZHANG Yan

    2014-01-01

    Two types of solutions (ZnSO4, MgSO4) were selected to study the influence of mineral admixtures on the electro-deposition healing effect of concrete cracks. Four parameters (i e, rates of weight gain, surface coating, crack closure and crack filling depth) were measured. The mineral composition of electro-deposits in the cracks was analyzed. The study shows that the healing effect of mortar specimens with 10%fly ash is the worst, while the healing effect of mortar specimens with 20%fly ash is better than that of the specimens without fly ash. The rates of weight gain, surface coating, crack closure and crack filling depth decrease with increasing content of the ground granulated blast-furnace slag(GGBS). The mineral admixtures have no influence on the composition of deposits.

  10. PREDICTION OF GLOBAL AND LOCAL SIMMENTAL AND RED HOLSTEIN FRIESIAN ADMIXTURE LEVELS IN SWISS FLECKVIEH CATTLE

    Directory of Open Access Journals (Sweden)

    Negar Khayatzadeh

    2015-09-01

    Full Text Available In this study we estimated levels of local ancestry for individuals of the Swiss Fleckvieh dairy cattle population. It is a composite breed descending from two pure breeds, Simmental (SIM and Red Holstein Friesian (RHF. Illumina BovineSNP50 Beadchip genotyping data for a total of 500 pure and admixed animals were used for the analysis. The global ancestries estimated by Hidden Markov model were 0.68 and 0.32 for RHF and SIM respectively. Local ancestry levels investigated along chromosomes 2, 3 and 13 indicated that there were some regions across the chromosomes exhibiting substantial fluctuations in admixture. On chromosome 2, in the range of 28 to 31, 41 to 46 and 54 to 56 Mb RHF ancestry is substantially higher than average (0.77-0.78. These regions on chromosome 2 are wide, indicating recent admixture. Along the segments on chromosome 2, many QTLs related to dairy, conformation, reproduction, health and carcass traits were found. We observed sharper excess in favour of SIM on chromosome 3, whereas different regions with excess of RHF and SIM were found out on Chromosome 13. At the first part of chromosome 13, an excess of RHF was observed. Moreover, in regions between 40 and 57 Mb excess of SIM, referred to recent admixture was detected. In respect of RHF chromosome segments in admixed animals, dairy, reproduction and health QTLs were found. In positions where more Simmental segments were detected, QTLs related to meat and carcass traits as well as udder health traits were found. In conclusion, the authors believe that estimation of local admixture levels in crossbred populations can add information to the composite breeds history of selection.

  11. Intraspecific genetic admixture and the morphological diversification of an estuarine fish population complex.

    Science.gov (United States)

    Dodson, Julian J; Bourret, Audrey; Barrette, Marie France; Turgeon, Julie; Daigle, Gaétan; Legault, Michel; Lecomte, Frédéric

    2015-01-01

    The North-east American Rainbow smelt (Osmerus mordax) is composed of two glacial races first identified through the spatial distribution of two distinct mtDNA lineages. Contemporary breeding populations of smelt in the St. Lawrence estuary comprise contrasting mixtures of both lineages, suggesting that the two races came into secondary contact in this estuary. The overall objective of this study was to assess the role of intraspecific genetic admixture in the morphological diversification of the estuarine rainbow smelt population complex. The morphology of mixed-ancestry populations varied as a function of the relative contribution of the two races to estuarine populations, supporting the hypothesis of genetic admixture. Populations comprising both ancestral mtDNA races did not exhibit intermediate morphologies relative to pure populations but rather exhibited many traits that exceeded the parental trait values, consistent with the hypothesis of transgressive segregation. Evidence for genetic admixture at the level of the nuclear gene pool, however, provided only partial support for this hypothesis. Variation at nuclear AFLP markers revealed clear evidence of the two corresponding mtDNA glacial races. The admixture of the two races at the nuclear level is only pronounced in mixed-ancestry populations dominated by one of the mtDNA lineages, the same populations showing the greatest degree of morphological diversification and population structure. In contrast, mixed-ancestry populations dominated by the alternate mtDNA lineage showed little evidence of introgression of the nuclear genome, little morphological diversification and little contemporary population genetic structure. These results only partially support the hypothesis of transgressive segregation and may be the result of the differential effects of natural selection acting on admixed genomes from different sources. PMID:25856193

  12. Intraspecific Genetic Admixture and the Morphological Diversification of an Estuarine Fish Population Complex

    OpenAIRE

    Dodson, Julian J.; Bourret, Audrey; Barrette, Marie France; Turgeon, Julie; Daigle, Gaétan; Legault, Michel; Lecomte, Frédéric

    2015-01-01

    The North-east American Rainbow smelt (Osmerus mordax) is composed of two glacial races first identified through the spatial distribution of two distinct mtDNA lineages. Contemporary breeding populations of smelt in the St. Lawrence estuary comprise contrasting mixtures of both lineages, suggesting that the two races came into secondary contact in this estuary. The overall objective of this study was to assess the role of intraspecific genetic admixture in the morphological diversification of...

  13. Plant cover and water balance in gravel admixtures at an arid waste-burial site

    International Nuclear Information System (INIS)

    Isolation of radioactive waste buried in unsaturated zones will require long-term control of recharge and erosion. Soil covers control recharge at and sites by storing rainwater close enough to the surface to be removed by evapotranspiration. Surface layers of rock or gravel control erosion at sites with sparse vegetation, but can also alter plant habitat and cause recharge through interred waste. As an alternative, gravel mixed into the uppermost soil law may control erosion ever the king-term better than surface gravel layers. Gravel admixtures may also not influence plant establishment or sod water balance in waste-site covers. The interactive effects of gravel admixture concentration, vegetation, and precipitation on soil water content and plant cover were measured at the US Department of Energy's Hanford Site. Results support use of a combination of vegetation and gravel admixtures for erosion control. Vegetation seasonally depleted root zone water storage to about 6.5 volume % regardless of precipitation amount or the presence of gravel admixture amendments. In contrast, yearly increases in soil water storage as deep as 225 cm in plots without vegetation may be a leading indicator of recharge. The composition and abundance of vegetation changed over time and with precipitation amount, but was not influenced by gravel amendments. Seeded wheatgrasses [Agropyron sibericum Wilde and Agropyron dasystachyum (Hook.) Scribn.] established only when irrigated with twice average precipitation, but persisted after the irrigation ceased. Cheatgrass (Bromus tectorum L.) and Russian thistle (Salsola kali L.) colonized areas receiving both irrigation and ambient precipitation. Stands with wheatgrasses extracted water more rapidly and depleted soil water to lower levels than cheatgrass-dominated stands. Increases in gravel cover and near-surface gravel concentrations after 5 yr were evidence of the formation of a protective gravel veneer. 44 refs., 8 figs., 2 tabs

  14. Tracing the origin of the east-west population admixture in the Altai region (Central Asia.

    Directory of Open Access Journals (Sweden)

    Mercedes González-Ruiz

    Full Text Available A recent discovery of Iron Age burials (Pazyryk culture in the Altai Mountains of Mongolia may shed light on the mode and tempo of the generation of the current genetic east-west population admixture in Central Asia. Studies on ancient mitochondrial DNA of this region suggest that the Altai Mountains played the role of a geographical barrier between West and East Eurasian lineages until the beginning of the Iron Age. After the 7th century BC, coinciding with Scythian expansion across the Eurasian steppes, a gradual influx of East Eurasian sequences in Western steppes is detected. However, the underlying events behind the genetic admixture in Altai during the Iron Age are still unresolved: 1 whether it was a result of migratory events (eastward firstly, westward secondly, or 2 whether it was a result of a local demographic expansion in a 'contact zone' between European and East Asian people. In the present work, we analyzed the mitochondrial DNA lineages in human remains from Bronze and Iron Age burials of Mongolian Altai. Here we present support to the hypothesis that the gene pool of Iron Age inhabitants of Mongolian Altai was similar to that of western Iron Age Altaians (Russia and Kazakhstan. Thus, this people not only shared the same culture (Pazyryk, but also shared the same genetic east-west population admixture. In turn, Pazyryks appear to have a similar gene pool that current Altaians. Our results further show that Iron Age Altaians displayed mitochondrial lineages already present around Altai region before the Iron Age. This would provide support for a demographic expansion of local people of Altai instead of westward or eastward migratory events, as the demographic event behind the high population genetic admixture and diversity in Central Asia.

  15. Compatibility between base concrete made with different chemical admixtures and surface hardener

    OpenAIRE

    Pinheiro-Alves, M.ª Teresa; Sequeira, Ana Rita; Bettencourt Ribeiro, António

    2012-01-01

    Many cases of cracking and detachment of the concrete surface have appeared in concrete floors where surface hardeners were used in Portugal. The main causes for cracking and delamination of trowelled concrete pavements are several and it is essential to control bleeding and the time available to perform the finishing operations. Several base concretes were made with different chemical admixtures and one type of surface hardeners. The purpose of this study was evaluating the influence of the ...

  16. Lime-based repair mortars with water-repellent admixtures: laboratory durability assessment

    OpenAIRE

    Nunes, C.; Slížková, Z. (Zuzana)

    2015-01-01

    Conservation of architectural structures using lime binders is currently an important research topic aiming compatibility, durability and sustainability. In this study, lime (L) and lime-metakaolin (LM) mortars were prepared with the addition of water-repellent admixtures: linseed oil, stand oil and a silane based water-repellent. Experimental results demonstrate that oil imparts higher hydrophobicity to both L and LM mixtures. Durability was assessed through freeze-thaw and NaCl crystal...

  17. Dissecting the genetic structure and admixture of four geographical Malay populations

    OpenAIRE

    Lian Deng; Boon-Peng Hoh; Dongsheng Lu; Woei-Yuh Saw; Rick Twee-Hee Ong; Anuradhani Kasturiratne; H Janaka de Silva; Bin Alwi Zilfalil; Norihiro Kato; Wickremasinghe, Ananda R; Yik-Ying Teo; Shuhua Xu

    2015-01-01

    The Malay people are an important ethnic composition in Southeast Asia, but their genetic make-up and population structure remain poorly studied. Here we conducted a genome-wide study of four geographical Malay populations: Peninsular Malaysian Malay (PMM), Singaporean Malay (SGM), Indonesian Malay (IDM) and Sri Lankan Malay (SLM). All the four Malay populations showed substantial admixture with multiple ancestries. We identified four major ancestral components in Malay populations: Austrones...

  18. Effect of water-repellent admixtures on the behaviour of aerial lime-based mortars

    OpenAIRE

    Izaguirre, A.; Lanas, J.; Alvarez, J I

    2009-01-01

    Two different anionic surfactants, sodium oleate and calcium stearate, commercialized as water repellents for cement-based mortars, were added to lime-based mortars in order to check whether they were improved by these admixtures. Different properties of lime-based mortars were evaluated: fresh state behaviour through water retention, air content and setting time, hardened state properties such as density, water absorption through capillarity, water vapour permeability, long-term compressive ...

  19. Reduction in nitrate leaching from a concrete waste form by using waterproofing admixture additions

    International Nuclear Information System (INIS)

    Admixture additions of active lime and tricalcium aluminate reduced leach rate about 20% during a seven-day test of a concrete waste form containing a nitrate bearing, aqueous waste. CaO was 5% more effective and, in SEM examination, appeared to hydrate to CaOH which expanded in the concrete pores and blocked water movement. Over time, this compound appeared to dissolve slowly in the water, and the barrier layer it produced slowly receded into the specimen interior

  20. Profile of Intravenous Admixture Compatibility in the Intensive Care Unit (ICU) Patients

    OpenAIRE

    Sharly Dwijayanti; Sylvi Irawati; Eko Setiawan

    2016-01-01

    which may directly impact to the outcome of treatment to the Intensive Care Unit (ICU) patients. The objective of this study was to identify the profile of compatibility and incompatibility among IV admixtures given to the ICU patients. This observational research was conducted prospectively to the patients admitted in the ICU at a private hospital in Surabaya from October–December 2014. In this research, compatibility data of IV drug and its solution was compared with drug brochure and Handb...

  1. Search for admixture of heavy neutrinos with masses between 5 and 55 keV

    OpenAIRE

    Markey, J.; Boehm, F.

    1985-01-01

    Using a magnetic spectrometer at a momentum resolution of 0.3%, we have studied the beta spectrum from 35S. We do not see evidence for the admixture of a heavy neutrino to the usual light (m~0) ν̃e accompanying beta decay, in the mass range between 5 and 50 keV, with a limit for the mixing strength of |U|2

  2. Effect of Chemical Admixtures on the Engineering Properties of Tropical Peat Soils

    Directory of Open Access Journals (Sweden)

    Bujang B.K. Huat

    2005-01-01

    Full Text Available This research describes a study on the effect of chemical (cement and lime admixtures on the index and engineering properties (compaction and unconfined strength of tropical peat soils. The ordinary Portland cement and hydrated lime were used. The amounts cement and lime added to the peat soil sample, as a percentage of the dry soil mass was in the range of 5-15% and 5-25%, respectively. The results of the study show that the addition of the chemical admixture, cement and lime, can improve the engineering properties of tropical peat soils. The soil liquid limit is found to decrease with an increase in the cement and lime content. The soil maximum dry density is found to increase while the optimum water content is found to decrease with an increase in the cement and lime content. The unconfined compressive strength of the soil is found to increase significantly with increase in cement and lime content, especially after a long curing period. However it is also found that higher organic content of the soil negate the positive effect of the cement and lime in altering (improving the mechanical properties of the soil. When comparing the performance of the cement and lime as a chemical admixture for the tropical peat soil, the ordinary Portland cement appears to perform better than the hydrated lime.

  3. Analysis of admixture and genetic structure of two Native American groups of Southern Argentinean Patagonia.

    Science.gov (United States)

    Sala, Andrea; Corach, Daniel

    2014-03-01

    Argentinean Patagonia is inhabited by people that live principally in urban areas and by small isolated groups of individuals that belong to indigenous aboriginal groups; this territory exhibits the lowest population density of the country. Mapuche and Tehuelche (Mapudungun linguistic branch), are the only extant Native American groups that inhabit the Argentinean Patagonian provinces of Río Negro and Chubut. Fifteen autosomal STRs, 17 Y-STRs, mtDNA full length control region sequence and two sets of Y and mtDNA-coding region SNPs were analyzed in a set of 434 unrelated individuals. The sample set included two aboriginal groups, a group of individuals whose family name included Native American linguistic root and urban samples from Chubut, Río Negro and Buenos Aires provinces of Argentina. Specific Y Amerindian haplogroup Q1 was found in 87.5% in Mapuche and 58.82% in Tehuelche, while the Amerindian mtDNA haplogroups were present in all the aboriginal sample contributors investigated. Admixture analysis performed by means of autosomal and Y-STRs showed the highest degree of admixture in individuals carrying Mapuche surnames, followed by urban populations, and finally by isolated Native American populations as less degree of admixture. The study provided novel genetic information about the Mapuche and Tehuelche people and allowed us to establish a genetic correlation among individuals with Mapudungun surnames that demonstrates not only a linguistic but also a genetic relationship to the isolated aboriginal communities, representing a suitable proxy indicator for assessing genealogical background.

  4. Chemical stability of an admixture combining ziconotide and bupivacaine during simulated intrathecal administration.

    Science.gov (United States)

    Shields, David; Montenegro, Rick; Aclan, Jennifer

    2007-10-01

    Objective.  To determine the stability of an admixture combining ziconotide with bupivacaine hydrochloride during simulated intrathecal infusion under laboratory conditions at 37°. Materials and Methods.  An admixture containing ziconotide (25 µg/mL) and bupivacaine hydrochloride (5 mg/mL) was stored in SynchroMed® II pumps at 37° and in control vials at either 37° or 5°. Using high-performance liquid chromatography, drug concentrations were determined from samples obtained at varying intervals during the 30-day study. Results.  After 30 days, pump ziconotide and bupivacaine hydrochloride concentrations measured an average of 86.9% and 99.4% of their initial concentrations, respectively. Control vials displayed similar degradation rates for both drugs. Statistical evaluation of the ziconotide 95% confidence interval indicated that the ziconotide concentration would meet or exceed 90% and 80% of initial concentration for 22 days and 45 days, respectively. Conclusions.  An admixture containing 25 µg/mL ziconotide and 5 mg/mL bupivacaine hydrochloride was 90% stable for 22 days and 80% stable for 45 days (extrapolated) in SynchroMed® II infusion pumps. PMID:22150945

  5. Study on Strength and Microstructure of Cement-Based Materials Containing Combination Mineral Admixtures

    Directory of Open Access Journals (Sweden)

    Meijuan Rao

    2016-01-01

    Full Text Available The compressive strength of complex binders containing two or three blended mineral admixtures in terms of glass powder (GP, limestone powder (LP, and steel slag powder (SP was determined by a battery solution type compressive testing machine. The morphology and microstructure characteristics of complex binder hydration products were also studied by microscopic analysis methods, such as XRD, TG-DTA, and SEM. The mechanical properties of the cement-based materials were analyzed to reveal the most appropriate mineral admixture type and content. The early sample strength development with GP was very slow, but it rapidly grew at later stages. The micro aggregate effect and pozzolanic reaction mutually occurred in the mineral admixture. In the early stage, the micro aggregate effect reduced paste porosity and the small particles connected with the cement hydration products to enhance its strength. In the later stage, the pozzolanic reaction of some components in the complex powder occurred and consumed part of the calcium hydroxide to form C-S-H gel, thus improving the hydration environment. Also, the produced C-S-H gel made the structure more compact, which improved the structure’s strength.

  6. Effect of chemical admixtures on properties of high-calcium fly ash geopolymer

    Science.gov (United States)

    Rattanasak, Ubolluk; Pankhet, Kanokwan; Chindaprasirt, Prinya

    2011-06-01

    Owing to the high viscosity of sodium silicate solution, fly ash geopolymer has the problems of low workability and rapid setting time. Therefore, the effect of chemical admixtures on the properties of fly ash geopolymer was studied to overcome the rapid set of the geopolymer in this paper. High-calcium fly ash and alkaline solution were used as starting materials to synthesize the geopolymer. Calcium chloride, calcium sulfate, sodium sulfate, and sucrose at dosages of 1wt% and 2wt% of fly ash were selected as admixtures based on concrete knowledge to improve the properties of the geopolymer. The setting time, compressive strength, and degree of reaction were recorded, and the microstructure was examined. The results show that calcium chloride significantly shortens both the initial and final setting times of the geopolymer paste. In addition, sucrose also delays the final setting time significantly. The degrees of reaction of fly ash in the geopolymer paste with the admixtures are all higher than those of the control paste. This contributes to the obvious increases in compressive strength.

  7. Chemical, Mechanical, and Durability Properties of Concrete with Local Mineral Admixtures under Sulfate Environment in Northwest China

    Directory of Open Access Journals (Sweden)

    Qingke Nie

    2014-05-01

    Full Text Available Over the vast Northwest China, arid desert contains high concentrations of sulfate, chloride, and other chemicals in the ground water, which poses serious challenges to infrastructure construction that routinely utilizes portland cement concrete. Rapid industrialization in the region has been generating huge amounts of mineral admixtures, such as fly ash and slags from energy and metallurgical industries. These industrial by-products would turn into waste materials if not utilized in time. The present study evaluated the suitability of utilizing local mineral admixtures in significant quantities for producing quality concrete mixtures that can withstand the harsh chemical environment without compromising the essential mechanical properties. Comprehensive chemical, mechanical, and durability tests were conducted in the laboratory to characterize the properties of the local cementitious mineral admixtures, cement mortar and portland cement concrete mixtures containing these admixtures. The results from this study indicated that the sulfate resistance of concrete was effectively improved by adding local class F fly ash and slag, or by applying sulfate resistance cement to the mixtures. It is noteworthy that concrete containing local mineral admixtures exhibited much lower permeability (in terms of chloride ion penetration than ordinary portland cement concrete while retaining the same mechanical properties; whereas concrete mixtures made with sulfate resistance cement had significantly reduced strength and much increased chloride penetration comparing to the other mixtures. Hence, the use of local mineral admixtures in Northwest China in concrete mixtures would be beneficial to the performance of concrete, as well as to the protection of environment.

  8. Chemical stability of ziconotide-clonidine hydrochloride admixtures with and without morphine sulfate during simulated intrathecal administration.

    Science.gov (United States)

    Shields, David; Montenegro, Rick

    2007-10-01

    Objective.  To determine the stability of ziconotide-clonidine hydrochloride admixtures with and without morphine sulfate during simulated intrathecal infusion under laboratory conditions at 37°. Materials and Methods.  Admixtures of ziconotide (25 µg/mL) and clonidine hydrochloride (2 mg/mL) with and without morphine sulfate (35 mg/mL) were stored in Medtronic SynchroMed® II pumps at 37°. Pumps were sampled immediately after filling and at four additional time points over the course of 28 (ziconotide-clonidine hydrochloride admixture) or 20 (ziconotide-clonidine hydrochloride-morphine sulfate admixture) days. Drug concentrations were determined using high-performance liquid chromatography. Results.  Ziconotide concentration exceeded 97% of initial at all time points when combined with clonidine alone; statistical evaluation indicated that both ziconotide and clonidine concentrations would remain above 90% of initial for more than 60 days. When compounded with both clonidine and morphine, ziconotide and clonidine concentrations declined; statistical evaluation indicated that the ziconotide concentration was 70% of initial after 20 days, and that clonidine would remain 90% stable for 42 days. Morphine was stable in the presence of ziconotide and clonidine. Conclusions.  A ziconotide-clonidine admixture was 90% stable for 60 days (extrapolated), and a ziconotide-clonidine-morphine admixture was 70% stable for 20 days. PMID:22150946

  9. Ultrafast scanning tunneling microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Botkin, D.A. [California Univ., Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley Lab., CA (United States)

    1995-09-01

    I have developed an ultrafast scanning tunneling microscope (USTM) based on uniting stroboscopic methods of ultrafast optics and scanned probe microscopy to obtain nanometer spatial resolution and sub-picosecond temporal resolution. USTM increases the achievable time resolution of a STM by more than 6 orders of magnitude; this should enable exploration of mesoscopic and nanometer size systems on time scales corresponding to the period or decay of fundamental excitations. USTM consists of a photoconductive switch with subpicosecond response time in series with the tip of a STM. An optical pulse from a modelocked laser activates the switch to create a gate for the tunneling current, while a second laser pulse on the sample initiates a dynamic process which affects the tunneling current. By sending a large sequence of identical pulse pairs and measuring the average tunnel current as a function of the relative time delay between the pulses in each pair, one can map the time evolution of the surface process. USTM was used to measure the broadband response of the STM`s atomic size tunnel barrier in frequencies from tens to hundreds of GHz. The USTM signal amplitude decays linearly with the tunnel junction conductance, so the spatial resolution of the time-resolved signal is comparable to that of a conventional STM. Geometrical capacitance of the junction does not appear to play an important role in the measurement, but a capacitive effect intimately related to tunneling contributes to the measured signals and may limit the ultimate resolution of the USTM.

  10. Ancestral proportions and admixture dynamics in geographically defined African Americans living in South Carolina.

    Science.gov (United States)

    Parra, E J; Kittles, R A; Argyropoulos, G; Pfaff, C L; Hiester, K; Bonilla, C; Sylvester, N; Parrish-Gause, D; Garvey, W T; Jin, L; McKeigue, P M; Kamboh, M I; Ferrell, R E; Pollitzer, W S; Shriver, M D

    2001-01-01

    We analyzed admixture in samples of six different African-American populations from South Carolina: Gullah-speaking Sea Islanders in coastal South Carolina, residents of four counties in the "Low Country" (Berkeley, Charleston, Colleton, and Dorchester), and persons living in the city of Columbia, located in central South Carolina. We used a battery of highly informative autosomal, mtDNA, and Y-chromosome markers. Two of the autosomal markers (FY and AT3) are linked and lie 22 cM apart on chromosome 1. The results of this study indicate, in accordance with previous historical, cultural, and anthropological evidence, a very low level of European admixture in the Gullah Sea Islanders (m = 3.5 +/- 0.9%). The proportion of European admixture is higher in the Low Country (m ranging between 9. 9 +/- 1.8% and 14.0 +/- 1.9%), and is highest in Columbia (m = 17.7 +/- 3.1%). A sex-biased European gene flow and a small Native American contribution to the African-American gene pool are also evident in these data. We studied the pattern of pairwise allelic associations between the FY locus and the nine other autosomal markers in our samples. In the combined sample from the Low Country (N = 548), a high level of linkage disequilibrium was observed between the linked markers, FY and AT3. Additionally, significant associations were also detected between FY and 4 of the 8 unlinked markers, suggesting the existence of significant genetic structure in this population. A continuous gene flow model of admixture could explain the observed pattern of genetic structure. A test conditioning on the overall admixture of each individual showed association of ancestry between the two linked markers (FY and AT3), but not between any of the unlinked markers, as theory predicts. Thus, even in the presence of genetic structure due to continuous gene flow or some other factor, it is possible to differentiate associations due to linkage from spurious associations due to genetic structure.

  11. Influence of Air Temperature on the Performance of Different Water-Reducing Admixtures with Respect to the Properties of Fresh and Hardened Mortar

    OpenAIRE

    Wilson Ricardo Leal Silva; Luiz Roberto Prudêncio; Alexandre Lima Oliveira; Gabriela Damo; Eduardo Tochetto

    2010-01-01

    The performance of water-reducing admixtures used in concrete is affected by the weather conditions to which the concrete mixture is exposed. The most used WRAs are lignosulfonate, naphthalene, and polycarboxylate. However, they react differently to weather conditions, especially to air temperature. Therefore, it can be useful to evaluate how temperature affects admixture performance. In this study, the performance of three admixtures (naphthalene, lignosulfonate, and polycarboxylate) was eva...

  12. Heart PET scan

    Science.gov (United States)

    ... nuclear medicine scan; Heart positron emission tomography; Myocardial PET scan ... A PET scan requires a small amount of radioactive material (tracer). This tracer is given through a vein (IV), ...

  13. Coronary Calcium Scan

    Science.gov (United States)

    ... the NHLBI on Twitter. What Is a Coronary Calcium Scan? A coronary calcium scan is a test ... you have calcifications in your coronary arteries. Coronary Calcium Scan Figure A shows the position of the ...

  14. Scan BIST with biased scan test signals

    Institute of Scientific and Technical Information of China (English)

    XIANG Dong; CHEN MingJing; SUN JiaGuang

    2008-01-01

    The conventional test-per-scan built-in self-test (BIST) scheme needs a number of shift cycles followed by one capture cycle.Fault effects received by the scan flip-flops are shifted out while shifting in the next test vector like scan testing.Unlike deterministic testing,it is unnecessary to apply a complete test vector to the scan chains.A new scan-based BIST scheme is proposed by properly controlling the test signals of the scan chains,Different biased random values are assigned to the test signals of scan flip-flops in separate scan chains.Capture cycles can be inserted at any clock cycle if necessary.A new testability estimation procedure according to the proposed testing scheme is presented.A greedy procedure is proposed to select a weight for each scan chain.Experimental results show that the proposed method can improve test effectiveness of scan-based BIST greatly,and most circuits can obtain complete fault coverage or very close to complete fault coverage.

  15. Effectiveness of shrinkage-reducing admixtures on Portland pozzolan cement concrete

    Directory of Open Access Journals (Sweden)

    Videla, C.

    2005-06-01

    Full Text Available Drying shrinkage causes tensile stress in restrained concrete members. Since all structural elements are subject to some degree of restraint, drying shrinkage is regarded to be one of the main causes of concrete cracking. The purpose of the present study was to evaluate the effectiveness of SRA in reducing drying shrinkage strain in Portland pozzolan cement concrete. The major variables examined included slump, admixture type and dose, and specimen size. The measured results indicate that any of the admixtures used in the study significantly reduced shrinkage. Concrete manufactured with shrinkage reducing admixtures shrank an average of 43% less than concrete without admixtures. As a rule, the higher the dose of admixture, the higher was its shrinkage reduction performance. The experimental results were compared to the shrinkage strain estimated with the ACI 209, CEB MC 90, B3, GL 2000, Sakata 1993 and Sakata 2001 models. Although none of these models was observed to accurately describe the behaviour of Portland pozzolan cement concrete with shrinkage reducing admixtures, the Sakata 2001 model, with a weighted coefficient of variation of under 30%, may be regarded to be roughly adequate.

    La retracción por secado es un fenómeno intrínseco del hormigón que produce tensiones de tracción en elementos restringidos de hormigón. Puesto que todos los elementos presentan algún grado de retracción, se considera a la retracción por secado como una de las principales causas de agrietamiento en proyectos de construcción en hormigón. Por lo tanto, el objetivo de esta investigación fue evaluar la efectividad de los aditivos reductores de retracción (SRA en hormigones fabricados con cemento Portland puzolánico. Las variables principales estudiadas incluyen el asentamiento de cono de Abrams, marca y dosis de aditivo reductor de retracción, y tamaño de espécimen de hormigón. Los resultados obtenidos permiten concluir que el uso de

  16. Inferring genome-wide patterns of admixture in Qataris using fifty-five ancestral populations

    Directory of Open Access Journals (Sweden)

    Omberg Larsson

    2012-06-01

    Full Text Available Abstract Background Populations of the Arabian Peninsula have a complex genetic structure that reflects waves of migrations including the earliest human migrations from Africa and eastern Asia, migrations along ancient civilization trading routes and colonization history of recent centuries. Results Here, we present a study of genome-wide admixture in this region, using 156 genotyped individuals from Qatar, a country located at the crossroads of these migration patterns. Since haplotypes of these individuals could have originated from many different populations across the world, we have developed a machine learning method "SupportMix" to infer loci-specific genomic ancestry when simultaneously analyzing many possible ancestral populations. Simulations show that SupportMix is not only more accurate than other popular admixture discovery tools but is the first admixture inference method that can efficiently scale for simultaneous analysis of 50-100 putative ancestral populations while being independent of prior demographic information. Conclusions By simultaneously using the 55 world populations from the Human Genome Diversity Panel, SupportMix was able to extract the fine-scale ancestry of the Qatar population, providing many new observations concerning the ancestry of the region. For example, as well as recapitulating the three major sub-populations in Qatar, composed of mainly Arabic, Persian, and African ancestry, SupportMix additionally identifies the specific ancestry of the Persian group to populations sampled in Greater Persia rather than from China and the ancestry of the African group to sub-Saharan origin and not Southern African Bantu origin as previously thought.

  17. Effect of poly car boxy late admixtures on portland cement paste setting and rheological behaviour

    Directory of Open Access Journals (Sweden)

    Puertas, F.

    2005-03-01

    Full Text Available The objective of the work was to determine the effects of polycarboxilated-type admixture on the setting times and the rheological properties of different types of cements including CEM I 42.5 R, CEM Il/B-V 42.5 N and CEM III/B 32.5 N, defined according to the UNE EN 197-1:2000 standard. The results show that there is a lineal relationship between the initial setting times and the admixture dosage. Mathematical equations that model this behaviour for each of the cements have been determined. The data obtained from the minislump test and from the rheological parameters determined using the rheometer (plastic viscosity and yield stress point to similar conclusions. It was also verified that the workability effect of the polycarboxilate admixture is most intense for blended cements.

    El objetivo de este trabajo ha sido estudiar el efecto de la dosificación de un aditivo basado en policarboxilatos sobre el inicio de tiempo de fraguado y las propiedades reo lógicas en pastas de diferentes tipos de cemento (CEM 142.5 R, CEM 11/ B-V42.5 NYCEMIII/B 32.5 N-Norma EN 197-1:2000. existe una relación lineal entre el inicio del fraguado y la dosificación del aditivo, se han determinado las ecuaciones matemáticas que describen este comportamiento para cada cemento, los resultados obtenidos sobre la fluidez de la pasta en el ensayo del "minislump" coinciden con la evolución de los valores de los parámetros reológicos (esfuerzo de cizalladura y viscosidad plástica determinados a través de un reómetro. el efecto fluidificante del aditivo superplastificante basado en policarboxilatos es mucho más marcado en cementos que contienen adiciones.

  18. Polar and brown bear genomes reveal ancient admixture and demographic footprints of past climate change

    Science.gov (United States)

    Miller, Webb; Schuster, Stephan C.; Welch, Andreanna J.; Ratan, Aakrosh; Bedoya-Reina, Oscar C.; Zhao, Fangqing; Kim, Hie Lim; Burhans, Richard C.; Drautz, Daniela I.; Wittekindt, Nicola E.; Tomsho, Lynn P.; Ibarra-Laclette, Enrique; Herrera-Estrella, Luis; Peacock, Elizabeth; Farley, Sean; Sage, George K.; Rode, Karyn; Obbard, Martyn E.; Montiel, Rafael; Bachmann, Lutz; Ingólfsson, Ólafur; Aars, Jon; Mailund, Thomas; Wiig, Øystein; Talbot, Sandra L.; Lindqvist, Charlotte

    2012-01-01

    Polar bears (PBs) are superbly adapted to the extreme Arctic environment and have become emblematic of the threat to biodiversity from global climate change. Their divergence from the lower-latitude brown bear provides a textbook example of rapid evolution of distinct phenotypes. However, limited mitochondrial and nuclear DNA evidence conflicts in the timing of PB origin as well as placement of the species within versus sister to the brown bear lineage. We gathered extensive genomic sequence data from contemporary polar, brown, and American black bear samples, in addition to a 130,000- to 110,000-y old PB, to examine this problem from a genome-wide perspective. Nuclear DNA markers reflect a species tree consistent with expectation, showing polar and brown bears to be sister species. However, for the enigmatic brown bears native to Alaska's Alexander Archipelago, we estimate that not only their mitochondrial genome, but also 5–10% of their nuclear genome, is most closely related to PBs, indicating ancient admixture between the two species. Explicit admixture analyses are consistent with ancient splits among PBs, brown bears and black bears that were later followed by occasional admixture. We also provide paleodemographic estimates that suggest bear evolution has tracked key climate events, and that PB in particular experienced a prolonged and dramatic decline in its effective population size during the last ca. 500,000 years. We demonstrate that brown bears and PBs have had sufficiently independent evolutionary histories over the last 4–5 million years to leave imprints in the PB nuclear genome that likely are associated with ecological adaptation to the Arctic environment.

  19. Application of a polycarboxylate ether admixture in RCC dam construction[ACI SP-239

    Energy Technology Data Exchange (ETDEWEB)

    Asmus, S.M.F.; Christensen, B.J.; Varley, N.J. [BASF Construction Chemicals Asia Pacific, Shanghai (China)

    2006-07-01

    Chemical admixtures are used in dam construction to improve plasticity of the dry materials mixture over time. Roller compacted concrete (RCC) has been used on many dam projects in China. However, the use of RCC has frequently resulted in water reduction problems. This paper provided details of an admixture based on polycarboxylate ether (PCE) which was developed to improve the quality of RCC constructions at the JinHong dam in China. Use of the polymer at the JinHong dam resulted in a vibration sensitive concrete that was sustained over time. Under identical mix-design and compaction conditions in the laboratory, specific gravity of the RCC was increased from 2417 kg/m{sup 3} to 2463 kg/m{sup 3}. The high specific gravity of the material resulted in satisfactory strength data from the dam project. The key-ratio of the splitting tensile strength versus compressive strength was higher than 8 per cent in all cases. A key advantage of the tailored PCE-RCC was the short Vebe times sustained over elapsed time in the RCC. Without additional compaction or vibration efforts, the specific density of RCC was better than conventional admixture technologies. The reduced viscosity provided cement paste films which formed on the surface of each layer of the RCC, which resulted in better bonding between the layers. It was concluded that the new PCE polymer is compatible with alternative retarder systems, which contributes to more extensive setting times under strict hydration regimes. 7 refs., 4 tabs., 4 figs.

  20. Rectification cleaning AsCl3 from the admixture of oxygen

    Directory of Open Access Journals (Sweden)

    Maznitska O. V.

    2008-06-01

    Full Text Available The process of the rectification cleaning of three-chlorous arsenic from the admixtures of products of his hydrolysis in the atmosphere of chlorous hydrogen has been considered in the article. Dependence of coefficient of relative volatility a three-chlorous arsenic from his concentration in muriatic solution is explored. The conduct of coefficient of relative volatility with concentrations of HCl and AsCl3 is compared. Saving of equalization of balance and equalization of working curve of column at such conduct of process of rectification is shown.

  1. Influence of Shrinkage-Reducing Admixtures on the Development of Plastic Shrinkage Cracks

    DEFF Research Database (Denmark)

    Lura, Pietro; Pease, Bradley Justin; Mazzotta, Guy;

    2007-01-01

    settlement of the concrete and tensile stress development in the surface of the concrete, which increase the potential for development of plastic shrinkage cracks. Specifically, this paper studies the development of plastic shrinkage cracks in mortars containing a commercially available shrinkage......-reducing admixture (SRA). Mortars containing SRA show fewer and narrower plastic shrinkage cracks than plain mortars when exposed to the same environmental conditions. It is proposed that the lower surface tension of the pore fluid in the mortars containing SRA results in less evaporation, reduced settlement......, reduced capillary tension, and lower crack-inducing stresses at the topmost layer of the mortar....

  2. The Properties and Applications of High-effective Mineral Admixture CRM for Concrete

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    To utilize industrial residue as building materials is not only the demand for modern concrete technology but also the requirements for maintaining ecological balance and sustainable development.CRM,a new high-effective mineral admixture for concrete,is developed recently from industrial residue,and the systematical studies on CRM's various properties have been performed.The laboratory tests,industrial tests and field applications have shown that CRM can be used as inorganic cementitious material to replace cement,and is also an excellent supplementary cementitious material for high performance concrete (HPC).

  3. A Comparative Study on Compressive and Flexural Strength of Concrete Containing Different Admixtures as Partial Replacement of Cement

    Directory of Open Access Journals (Sweden)

    Apoorv Singh

    2014-09-01

    Full Text Available Concrete is the most widely used material in the world today. This paper is about the comparative study of the flexural strength and compressive strength of concrete when different admixtures are used as partial replacement of cement in the concrete mix. The mineral admixtures that are used here are Silica Fume, Rice Husk Ash and Iron slag as partial replacement of cement. All these materials are industrial waste products and are abundantly available nowadays. These materials have high silica content and pozzolanic properties and can be effectively used as a replacement of cement during the formation of High Performance Concrete. Compressive and Flexural strength are the two most important characteristic of concrete and are calculated for the hardened concrete to analyze the load bearing capacity for design purposes. Thus for the effective judgment of type of mineral admixtures to be used a comparative study is very useful.

  4. Conventional cerebrospinal fluid scanning

    Energy Technology Data Exchange (ETDEWEB)

    Schicha, H.

    1985-06-01

    Conventional cerebrospinal fluid scanning (CSF scanning) today is mainly carried out in addition to computerized tomography to obtain information about liquor flow kinetics. Especially in patients with communicating obstructive hydrocephalus, CSF scanning is clinically useful for the decision for shunt surgery. In patients with intracranial cysts, CSF scanning can provide information about liquor circulation. Further indications for CSF scanning include the assessment of shunt patency especially in children, as well as the detection and localization of cerebrospinal fluid leaks.

  5. Improvement Of Sub-Grade Soil Properties Using Admixture Quarry Dust And Woven Geo-Textile

    Directory of Open Access Journals (Sweden)

    G. Priya Vasudha

    2015-08-01

    Full Text Available Abstract The important factor for design and construction of pavement is the behavior of underlying sub-grade. Large deformations in the sub-grade will lead to a continuous deterioration of the paved surface. As the sub-grade soil is too weak to bear the load engineering solutions such as geo reinforcement using geo-synthetics are additives which are earlier used in sub-grade improvement and such experimental study is carried by pervious authors. This paper deals with the sub-grade improvement using geo-textile as a reinforcement sheet and quarry dust as admixtures. In order to increase the strength of the sub-grade the quarry dust is varied with different percentages i.e. 0 5 10 15 20 and 25. In this study Proctors compaction tests and CBR soaked and unsoaked tests are conducted on locally available soil with reinforced material and with admixture. For this study it is identified that the engineering properties of the soil is improved in all conditions. The soil with quarry dust at optimum value is 20 has CBR soaked value is obtained 6.83 and unsoaked value is obtained 7.02 is increased when compared with conventionally soil. The soil quarry dust at optimum value is at 20 and Geo-textile has CBR soaked value is 6.59 and unsoaked value is 8.95 is increased when compared with conventionally soil and soil with quarry dust.

  6. Early-age Electrical Resistivity and Reactive Capacity of Mineral Admixtures in Mortars

    Institute of Scientific and Technical Information of China (English)

    LIANG Wenquan; HE Zhen; ZHANG Yongchuan; CHEN Meizhu; YANG Huaquan

    2006-01-01

    A non-contacting electrical resistivity measurement device was used to investigate the effect of different types and contents of mineral admixtures on the hydration performance of mortars during early age. The experimental results show that the changes of measured resistivity with time of hydration can be used to describe the hydration characteristics of cement- based materials, as well as the physical and chemical behavior of fly ash; blast furnace slag and silica fume at the very early ages. With an increasing replacement ratio of mineral admixtures, for the specimens blended with fly ash or slag, the resistivity increases firstly, then the following flatting period extends and after setting the resistivity increasing becomes slow and consequently a lower resistivity value at 24 hours occurs. This is due to the dilution effect and lower pozzolanic/ hydraulic activity of fly ash and slag. However, for the samples incorporated with silica fume, the resistivity value through 24 hours is lower with shorter flatting period and larger slope in the resistivity curves, which is because of its particle size effect and higher pozzolanic activity of silica fume. Moreover, non-contacting resistivity measurement might provide a helpful information to predict the long term performance including the durability of cement-based materials at early ages.

  7. The effect of chemical admixtures and mineral additives on the properties of self-compacting mortars

    Energy Technology Data Exchange (ETDEWEB)

    Mustafa Sahmaran; Heru Ari Christianto; Ismail Ozgur Yaman [Middle East Technical University, Ankara (Turkey). Department of Civil Engineering

    2006-05-15

    Mortar serves as the basis for the workability properties of self-compacting concrete (SCC) and these properties could be assessed by self-compacting mortars (SCM). In fact, assessing the properties of SCM is an integral part of SCC design. The objective of this study was to evaluate the effectiveness of various mineral additives and chemical admixtures in producing SCMs. For this purpose, four mineral additives (fly ash, brick powder, limestone powder, and kaolinite), three superplasticizers (SP), and two viscosity modifying admixtures (VMA) were used. Within the scope of the experimental program, 43 mixtures of SCM were prepared keeping the amount of mixing water and total powder content (Portland cement and mineral additives) constant. Workability of the fresh mortar was determined using mini V-funnel and mini slump flow tests. The setting time of the mortars, were also determined. The hardened properties that were determined included ultrasonic pulse velocity and strength determined at 28 and 56 days. It was concluded that among the mineral additives used, fly ash and limestone powder significantly increased the workability of SCMs. On the other hand, especially fly ash significantly increased the setting time of the mortars, which can, however, be eliminated through the use of ternary mixtures, such as mixing fly ash with limestone powder. The two polycarboxyl based SPs yield approximately the same workability and the melamine formaldehyde based SP was not as effective as the other two.

  8. Preparation of High Impermeable and Crack-resistance Chemical Admixture and Its Mechanism

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A kind of high impermeable and crack-resistance chemical admixture (HICRCA) was prepared, which is a compound chemical admixture composed of an expansion ingredient,density ingredient, and organic hydrophobic poreblocking ingredient. The results of the experiments indicate that the addition of HICRCA improves mortar and concrete in the following performances:(1) perfect workability: slump is more than 22cm, the slump after 3h is about 16cm; (2)high impermeability:for the mortar,the pervious height under a water pressure of 1.5MPa is 1.5cm,for the concrete, the pervious height under a water pressure of 5.0MPa is 2.2cm;(3)high crack-resistance:there is a micro-expansion at the age of 90d;(4)high compressivestrength:compared with the controlled concrete,the compressive strengths at the age of 3d and 28d are improved by 66.4% and 62.0%, respectively.At the same time,the effects of different curing condition on mortar and concrete expansive and shrinkage performance were studied.In addition,the impermeable and crack-resistance mechanism was investigated in the present paper.

  9. Growth and characterization of pure and semiorganic nonlinear optical Lithium Sulphate admixtured l-alanine crystal

    Science.gov (United States)

    Vela, T.; Selvarajan, P.; Freeda, T. H.; Balasubramanian, K.

    2013-04-01

    Lithium sulphate admixtured l-alanine (LSLA) salt was synthesized and the solubility of the commercially available l-alanine and the synthesized LSLA sample was determined in de-ionized water at various temperatures. In accordance with the solubility data, the saturated aqueous solutions of l-alanine and lithium admixtured l-alanine were prepared separately and the single crystals of the samples were grown by the solution method with a slow evaporation technique. Studying single x-ray diffraction shows that pure and LSLA crystal belong to the orthorhombic system with a non-centrosymmetric space group P212121. Using the powder x-ray diffraction study, the crystallinity of the grown crystals is confirmed and the diffraction peaks are indexed. The various functional groups present in the pure and LSLA crystal are elucidated from Fourier transform infrared spectroscopy study. UV-visible transmittance is recorded to study the optical transmittance range for the grown crystals. The powder second harmonic generation test confirms the nonlinear optical property of the grown crystals. From the microhardness test, the hardness of the grown crystals is estimated. The dielectric behaviour, such as the dielectric constant and the loss of the sample, are measured as a function of temperature and frequency. The ac conductivity of the grown crystals is also studied and the activation energy is calculated.

  10. Growth and characterization of pure and semiorganic nonlinear optical Lithium Sulphate admixtured l-alanine crystal

    International Nuclear Information System (INIS)

    Lithium sulphate admixtured l-alanine (LSLA) salt was synthesized and the solubility of the commercially available l-alanine and the synthesized LSLA sample was determined in de-ionized water at various temperatures. In accordance with the solubility data, the saturated aqueous solutions of l-alanine and lithium admixtured l-alanine were prepared separately and the single crystals of the samples were grown by the solution method with a slow evaporation technique. Studying single x-ray diffraction shows that pure and LSLA crystal belong to the orthorhombic system with a non-centrosymmetric space group P212121. Using the powder x-ray diffraction study, the crystallinity of the grown crystals is confirmed and the diffraction peaks are indexed. The various functional groups present in the pure and LSLA crystal are elucidated from Fourier transform infrared spectroscopy study. UV–visible transmittance is recorded to study the optical transmittance range for the grown crystals. The powder second harmonic generation test confirms the nonlinear optical property of the grown crystals. From the microhardness test, the hardness of the grown crystals is estimated. The dielectric behaviour, such as the dielectric constant and the loss of the sample, are measured as a function of temperature and frequency. The ac conductivity of the grown crystals is also studied and the activation energy is calculated. (paper)

  11. Topographic Digital Raster Graphics, USGS quadrangle maps scanned, merged and projected to County Coordinate System, Published in 1990, 1:24000 (1in=2000ft) scale, Brown County, WI.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Topographic Digital Raster Graphics dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Hardcopy Maps information as of 1990. It...

  12. Aerial Photography and Imagery, Ortho-Corrected, 1961 Aerial photography maps that have been scanned and georefernced for use within Madison County's GIS., Published in 1961, 1:7200 (1in=600ft) scale, Madison County Council of Governments.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Aerial Photography and Imagery, Ortho-Corrected dataset, published at 1:7200 (1in=600ft) scale, was produced all or in part from Hardcopy Maps information as...

  13. Scan matching SLAM in underwater environments

    OpenAIRE

    Mallios, Angelos; Ridao Rodríguez, Pere; Ribas Romagós, David; Hernàndez Bes, Emili

    2014-01-01

    This paper proposes a pose-based algorithm to solve the full simultaneous localization and mapping problem for autonomous underwater vehicle (AUV) navigating in unknown and possibly unstructured environments. The proposed method first estimates the local path traveled by the robot while forming the acoustic image (scan) with range data coming from a mono-beam rotating sonar head, providing position estimates for correcting the distortions that the vehicle motion produces in the scans. Then, c...

  14. Experimental Investigation of Droplet Evaporation of Water with Ground Admixtures while Motion in a Flame of Liquid Fuel

    Directory of Open Access Journals (Sweden)

    Dmitriyenko Margarita A.

    2016-01-01

    Full Text Available The evaporation features for the atomized flow of suspension on the base of water with ground admixtures in an area of high-temperature combustion products of liquid flammable substance (acetone were investigated experimentally by the optical methods of gas flow diagnostic and the high-speed video recording. The scales of influence of clay and silt concentration in droplets of atomized flow on the intensity of its evaporation were determined. The approximation dependences describing a decrease in typical size of suspension droplets at various values of ground admixtures were obtained.

  15. Scanning evanescent electro-magnetic microscope

    Science.gov (United States)

    Xiang, Xiao-Dong; Gao, Chen

    2001-01-01

    A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.

  16. Rapid Frequency Scan EPR

    OpenAIRE

    Tseitlin, Mark; Rinard, George A.; Quine, Richard W.; Eaton, Sandra S.; Eaton, Gareth R.

    2011-01-01

    In rapid frequency scan EPR with triangular scans, sufficient time must be allowed to insure that the magnetization in the x,y plane decays to baseline at the end of the scan, which typically is about 5 T2 after the spins are excited. To permit relaxation of signals excited toward the extremes of the scan the total scan time required may be much longer than 5 T2. However, with periodic, saw-tooth excitation, the slow-scan EPR spectrum can be recovered by Fourier deconvolution of data recorded...

  17. RBC nuclear scan

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003835.htm RBC nuclear scan To use the sharing features on this page, please enable JavaScript. An RBC nuclear scan uses small amounts of radioactive material to ...

  18. MR guided spatial normalization of SPECT scans

    International Nuclear Information System (INIS)

    Full text: In SPECT population studies where magnetic resonance (MR) scans are also available, the higher resolution of the MR scans allows for an improved spatial normalization of the SPECT scans. In this approach, the SPECT images are first coregistered to their corresponding MR images by a linear (affine) transformation which is calculated using SPM's mutual information maximization algorithm. Non-linear spatial normalization maps are then computed either directly from the MR scans using SPM's built in spatial normalization algorithm, or, from segmented TI MR images using DARTEL, an advanced diffeomorphism based spatial normalization algorithm. We compare these MR based methods to standard SPECT based spatial normalization for a population of 27 fibromyalgia patients and 25 healthy controls with spin echo T1 scans. We identify significant perfusion deficits in prefrontal white matter in FM patients, with the DARTEL based spatial normalization procedure yielding stronger statistics than the standard SPECT based spatial normalization. (author)

  19. The “Grep” Command But Not FusionMap, FusionFinder or ChimeraScan Captures the CIC-DUX4 Fusion Gene from Whole Transcriptome Sequencing Data on a Small Round Cell Tumor with t(4;19)(q35;q13)

    OpenAIRE

    Ioannis Panagopoulos; Ludmila Gorunova; Bodil Bjerkehagen; Sverre Heim

    2014-01-01

    Whole transcriptome sequencing was used to study a small round cell tumor in which a t(4;19)(q35;q13) was part of the complex karyotype but where the initial reverse transcriptase PCR (RT-PCR) examination did not detect a CIC-DUX4 fusion transcript previously described as the crucial gene-level outcome of this specific translocation. The RNA sequencing data were analysed using the FusionMap, FusionFinder, and ChimeraScan programs which are specifically designed to identify fusion genes. Fusio...

  20. Limit on a right-handed admixture to the weak b→c current from semileptonic decays

    International Nuclear Information System (INIS)

    We determine an upper bound for a possible right-handed b→c quark current admixture in semileptonic B→Xcl-ν decays from a simultaneous fit to moments of the lepton-energy and hadronic-mass distribution measured as a function of the lower limit on the lepton energy, using data measured by the BABAR detector. The right-handed admixture is parametrized by a new parameter cR as coefficient of computed moments with right-handed quark current. For the standard-model part we use the prediction of the heavy-quark expansion up to order 1/mb3 and perturbative corrections and for the right-handed contribution only up to order 1/mb2 and perturbative corrections. We find cR'=0.05-0.50+0.33 in agreement with the standard-model prediction of zero. Additionally, we give a constraint on a possible right-handed admixture from exclusive decays, which is with a value of cR'=0.01±0.03 more restrictive than our value from the inclusive fit. The difference in |Vcb| between the inclusive and exclusive extraction is only slightly reduced when allowing for a right-handed admixture in the range of cR'=0.01±0.03.

  1. Pulmonary ventilation/perfusion scan

    Science.gov (United States)

    V/Q scan; Ventilation/perfusion scan; Lung ventilation/perfusion scan ... A pulmonary ventilation/perfusion scan is actually two tests. They may be done separately or together. During the perfusion scan, a health care ...

  2. Pulmonary ventilation/perfusion scan

    Science.gov (United States)

    V/Q scan; Ventilation/perfusion scan; Lung ventilation/perfusion scan ... A pulmonary ventilation/perfusion scan is actually two tests. They may be done separately or together. During the perfusion scan, a health ...

  3. Development of admixture to produce pumping-concrete with large amount of ordinary-fineness-slag

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.; Sun, Z.; Zhang, G. [Tongji Univ., College of Materials Science and Enginnering, Shanghai (China); Zhou, A. W. Z.; Liu, Q.; Chen, K. [HI CON Huaxi Concrete Admixtures Co., Ltd., Sichuan (China)

    1998-12-31

    A special admixture - WZ - which can be applied to prepare pumping-concrete with large amount of OFS to solve the strength problem of slag was developed. The activating components of WZ include no Cl or SO{sub 4}{sup 2}. As a result, the addition of WZ is an effective way to make use of industrial waste, reduce the cost of concrete, improve its durability, and protect the environment at the same time. Impermeability, freezing-thawing resistance, chemical corrosion resistance and resistance to carbonation were found to be superior to concrete of the same strength using only cement as bonding material. Dry shrinking ratio was less than the shrinking ratio for ordinary concrete. 6 refs., 8 tabs., 1 fig.

  4. Some radiation-optical properties of fluorphlogopite with admixture of vanadium

    Energy Technology Data Exchange (ETDEWEB)

    Avesov, A.D.; Gasanov, E.M. (AN Uzbekskoj SSR, Tashkent. Inst. Yadernoj Fiziki)

    1982-10-16

    A study is reported on crystals of synthetic mica fluorphlogopite KMg/sub 3/(AlSi/sub 3/O/sub 10/)F/sub 2/ with vanadium admixtures of 0.5 to 5%. Optical absorption spectra of fluorphlogopite samples neutron irradiated with doses of 10/sup 18/, 5 x 10/sup 18/, and 2.5 x 10/sup 19/ cm/sup -2/ show additional absorption bands at 300 to 330 and 560 nm. Most clearly these bands are observed in samples having small amounts of V/sub 2/O/sub 5/. It was concluded that under neutron irradiation in vanadium fluorphlogopite substitution of F/sup -/ anions by O/sup 2 -/ anions takes place, coupled with a valence transition V/sup 2 +/ ..-->.. V/sup 3 +/ upon growing irradiation dose.

  5. Plastic shrinkage of mortars with shrinkage reducing admixture and lightweight aggregates studied by neutron tomography

    Energy Technology Data Exchange (ETDEWEB)

    Wyrzykowski, Mateusz, E-mail: mateusz.wyrzykowski@empa.ch [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); Lodz University of Technology, Department of Building Physics and Building Materials, Lodz (Poland); Trtik, Pavel [Paul Scherrer Institute, Laboratory for Neutron Scattering and Imaging, Villigen (Switzerland); Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); Münch, Beat [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); Weiss, Jason [Purdue University, School of Civil Engineering, West Lafayette (United States); Vontobel, Peter [Paul Scherrer Institute, Laboratory for Neutron Scattering and Imaging, Villigen (Switzerland); Lura, Pietro [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); ETH Zurich, Institute for Building Materials (IfB), Zurich (Switzerland)

    2015-07-15

    Water transport in fresh, highly permeable concrete and rapid water evaporation from the concrete surface during the first few hours after placement are the key parameters influencing plastic shrinkage cracking. In this work, neutron tomography was used to determine both the water loss from the concrete surface due to evaporation and the redistribution of fluid that occurs in fresh mortars exposed to external drying. In addition to the reference mortar with a water to cement ratio (w/c) of 0.30, a mortar with the addition of pre-wetted lightweight aggregates (LWA) and a mortar with a shrinkage reducing admixture (SRA) were tested. The addition of SRA reduced the evaporation rate from the mortar at the initial stages of drying and reduced the total water loss. The pre-wetted LWA released a large part of the absorbed water as a consequence of capillary pressure developing in the fresh mortar due to evaporation.

  6. Influence of Mineral Admixtures on the Permeability of Lightweight Aggregate Concrete

    Institute of Scientific and Technical Information of China (English)

    WANG Fazhou; HU Shuguang; DING Qingjun; PENG yanzhou

    2005-01-01

    The permeability of lightweight aggregate concrete was studied. Some efforts were taken to increase the resistance of lightweight aggregate concrete (LC) to water penetration by using the mineral admixtures of fly ash, granulated blast furnace slag or silica fume. Accelerated chloride penetrability test and liquid atmosphere press method were used to study the anti-permeability of lightweight aggregate concrete. The experimental results show that fly ash, granulated blast furnace slag and silica fume can decrease the permeability of lightweight aggregate concrete, but the effect of granulated blast furnace slag is poor. According to the SEM and pore structure analyzing results,an interface self-reinforcing effect model was presented and the reinforced mechanism of mineral mixture on LC was discussed according to the model described by authors.

  7. Effect of Admixtures on the Yield Stresses of Cement Pastes under High Hydrostatic Pressures

    Directory of Open Access Journals (Sweden)

    Hong Jae Yim

    2016-03-01

    Full Text Available When cement-based materials are transported at a construction site, they undergo high pressures during the pumping process. The rheological properties of the materials under such high pressures are unknown, and estimating the workability of the materials after pumping is a complex problem. Among various influential factors on the rheology of concrete, this study investigated the effect of mineral and chemical admixtures on the high-pressure rheology. A rheometer was fabricated that could measure the rheological properties while maintaining a high pressure to simulate the pumping process. The effects of superplasticizer, silica fume, nanoclay, fly ash, or ground granulated blast furnace slag were investigated when mixed with two control cement pastes. The water-to-cement ratios were 0.35 and 0.50.

  8. Cultivar origin and admixture detection in Turkish olive oils by SNP-based CAPS assays.

    Science.gov (United States)

    Uncu, Ali Tevfik; Frary, Anne; Doganlar, Sami

    2015-03-01

    The aim of this study was to establish a DNA-based identification key to ascertain the cultivar origin of Turkish monovarietal olive oils. To reach this aim, we sequenced short fragments from five olive genes for SNP (single nucleotide polymorphism) identification and developed CAPS (cleaved amplified polymorphic DNA) assays for SNPs that alter restriction enzyme recognition motifs. When applied on the oils of 17 olive cultivars, a maximum of five CAPS assays were necessary to discriminate the varietal origin of the samples. We also tested the efficiency and limit of our approach for detecting olive oil admixtures. As a result of the analysis, we were able to detect admixing down to a limit of 20%. The SNP-based CAPS assays developed in this work can be used for testing and verification of the authenticity of Turkish monovarietal olive oils, for olive tree certification, and in germplasm characterization and preservation studies.

  9. Scan path entropy and Arrow plots: Capturing scanning behavior of multiple observers

    Directory of Open Access Journals (Sweden)

    Ignace T C Hooge

    2013-12-01

    Full Text Available Designers of visual communication material want their material to attract and retain attention. In marketing research, heat maps, dwell time, and time to AOI first hit are often used as evaluation parameters. Here we present two additional measures 1 scan path entropy to quantify gaze guidance and 2 the arrow plot to visualize the average scan path. Both are based on string representations of scan paths. The latter also incorporates transition matrices and time required for 50% of the observers to first hit AOIs (T50. The new measures were tested in an eye tracking study (48 observers, 39 advertisements. Scan path entropy is a sensible measure for gaze guidance and the new visualization method reveals aspects of the average scan path and gives a better indication in what order global scanning takes place.

  10. Scan path entropy and arrow plots: capturing scanning behavior of multiple observers.

    Science.gov (United States)

    Hooge, Ignace; Camps, Guido

    2013-01-01

    Designers of visual communication material want their material to attract and retain attention. In marketing research, heat maps, dwell time, and time to AOI first hit are often used as evaluation parameters. Here we present two additional measures (1) "scan path entropy" to quantify gaze guidance and (2) the "arrow plot" to visualize the average scan path. Both are based on string representations of scan paths. The latter also incorporates transition matrices and time required for 50% of the observers to first hit AOIs (T50). The new measures were tested in an eye tracking study (48 observers, 39 advertisements). Scan path entropy is a sensible measure for gaze guidance and the new visualization method reveals aspects of the average scan path and gives a better indication in what order global scanning takes place. PMID:24399993

  11. Multilocus Bayesian Estimates of Intra-Oceanic Genetic Differentiation, Connectivity, and Admixture in Atlantic Swordfish (Xiphias gladius L..

    Directory of Open Access Journals (Sweden)

    Brad L Smith

    Full Text Available Previous genetic studies of Atlantic swordfish (Xiphias gladius L. revealed significant differentiation among Mediterranean, North Atlantic and South Atlantic populations using both mitochondrial and nuclear DNA data. However, limitations in geographic sampling coverage, and the use of single loci, precluded an accurate placement of boundaries and of estimates of admixture. In this study, we present multilocus analyses of 26 single nucleotide polymorphisms (SNPs within 10 nuclear genes to estimate population differentiation and admixture based on the characterization of 774 individuals representing North Atlantic, South Atlantic, and Mediterranean swordfish populations. Pairwise FST values, AMOVA, PCoA, and Bayesian individual assignments support the differentiation of swordfish inhabiting these three basins, but not the current placement of the boundaries that separate them. Specifically, the range of the South Atlantic population extends beyond 5°N management boundary to 20°N-25°N from 45°W. Likewise the Mediterranean population extends beyond the current management boundary at the Strait of Gibraltar to approximately 10°W. Further, admixture zones, characterized by asymmetric contributions of adjacent populations within samples, are confined to the Northeast Atlantic. While South Atlantic and Mediterranean migrants were identified within these Northeast Atlantic admixture zones no North Atlantic migrants were identified respectively in these two neighboring basins. Owing to both, the characterization of larger number of loci and a more ample spatial sampling coverage, it was possible to provide a finer resolution of the boundaries separating Atlantic swordfish populations than previous studies. Finally, the patterns of population structure and admixture are discussed in the light of the reproductive biology, the known patterns of dispersal, and oceanographic features that may act as barriers to gene flow to Atlantic swordfish.

  12. Ancestry analysis reveals a predominant Native American component with moderate European admixture in Bolivians.

    Science.gov (United States)

    Heinz, Tanja; Alvarez-Iglesias, Vanesa; Pardo-Seco, Jacobo; Taboada-Echalar, Patricia; Gómez-Carballa, Alberto; Torres-Balanza, Antonio; Rocabado, Omar; Carracedo, Angel; Vullo, Carlos; Salas, Antonio

    2013-09-01

    We have genotyped 46 Ancestry Informative Markers (AIMs) in two of the most populated areas in Bolivia, namely, La Paz (Andean region; n=105), and Chuquisaca (Sub-Andean region; n=73). Using different analytical tools, we inferred admixture proportions of these two American communities by comparing the genetic profiles with those publicly available from the CEPH (Centre d'Etude du Polymorphisme Humain) panel representing three main continental groups (Africa, Europe, and America). By way of simulations, we first evaluated the minimum sample size needed in order to obtain accurate estimates of ancestry proportions. The results indicated that sample sizes above 30 individuals could be large enough to estimate main continental ancestry proportions using the 46 AIMs panel. With the exception of a few individuals, the results also indicated that Bolivians showed a predominantly Native American ancestry with variable levels of European admixture. The proportions of ancestry were statistically different in La Paz and Chuquisaca: the Native American component was 86% and 77% (Mann-Whitney U-test: un-adjusted P-value=2.1×10(-5)), while the European ancestry was 13% and 21% (Mann-Whitney U-test: un-adjusted P-value=3.6×10(-5)), respectively. The African ancestry in Bolivians captured by the AIMs analyzed in the present study was below 2%. The inferred ancestry of Bolivians fits well with previous studies undertaken on haplotype data, indicating a major proportion of Native American lineages. The genetic differences observed in these two groups suggest that forensic genetic analysis should be better performed based on local databases built in the main Bolivian areas.

  13. Genetic structure of the population of Cabo Verde (west Africa): evidence of substantial European admixture.

    Science.gov (United States)

    Parra, E J; Ribeiro, J C; Caeiro, J L; Riveiro, A

    1995-08-01

    The population of Cabo Verde was founded in the fifteenth century (1462), on the basis of slaves brought from the West African coast and a few Europeans, mainly from Portugal. The polymorphism of six red cell enzymes (ADA, AK1, ALAD, ESD, GLO1, and PGD) and ten plasma proteins (AHSG, BF, F13A, F13B, GC, HP, ORM, PLG, TBG, and TF) was studied in a sample of 268 individuals from Cabo Verde (West Africa). There is no statistical evidence of genetic heterogeneity between the two groups of islands which constitute the archipelago, Barlavento and Sotavento. The gene frequency distribution observed in Cabo Verde differs, in many markers, from that of West African populations, suggesting an important European influence. The proportion of Caucasian genes in the population of Cabo Verde has been calculated to be M = 0.3634 +/- 0.0510, and the considerable dispersion of the locus-specific admixture estimates seems to indicate random drift has also played a role in the evolution of the allele frequencies in the archipelago. Partition of the variance of the mean estimate in evolutionary and sampling variance shows the evolutionary variance is more than ten times higher than the sampling variance. When dendrograms are constructed on the basis of different genetic distances, the population of Cabo Verde clusters with Afro-Americans, forming a different group from the populations of the African continent. This is interpreted as a consequence of the importance of Caucasian admixture both in Afro-Americans and in the population of Cabo Verde. PMID:7485435

  14. Maternal admixture and population structure in Mexican-Mestizos based on mtDNA haplogroups.

    Science.gov (United States)

    Martínez-Cortés, Gabriela; Salazar-Flores, Joel; Haro-Guerrero, Javier; Rubi-Castellanos, Rodrigo; Velarde-Félix, Jésus S; Muñoz-Valle, José F; López-Casamichana, Mavil; Carrillo-Tapia, Eduardo; Canseco-Avila, Luis M; Bravi, Claudio M; López-Armenta, Mauro; Rangel-Villalobos, Héctor

    2013-08-01

    The maternal ancestry (mtDNA) has important applications in different research fields, such as evolution, epidemiology, identification, and human population history. This is particularly interesting in Mestizos, which constitute the main population in Mexico (∼93%) resulting from post-Columbian admixture between Spaniards, Amerindians, and African slaves, principally. Consequently, we conducted minisequencing analysis (SNaPshot) of 11 mitochondrial single-nucleotide polymorphisms in 742 Mestizos of 10 populations from different regions in Mexico. The predominant maternal ancestry was Native American (92.9%), including Haplogroups A, B, C, and D (47, 23.7, 15.9, and 6.2%, respectively). Conversely, European and African ancestries were less frequent (5.3 and 1.9%, respectively). The main characteristics of the maternal lineages observed in Mexican-Mestizos comprised the following: 1) contrasting geographic gradient of Haplogroups A and C; 2) increase of European lineages toward the Northwest; 3) low or absent, but homogeneous, African ancestry throughout the Mexican territory; 4) maternal lineages in Mestizos roughly represent the genetic makeup of the surrounding Amerindian groups, particularly toward the Southeast, but not in the North and West; 5) continuity over time of the geographic distribution of Amerindian lineages in Mayas; and 6) low but significant maternal population structure (FST  = 2.8%; P = 0.0000). The average ancestry obtained from uniparental systems (mtDNA and Y-chromosome) in Mexican-Mestizos was correlated with previous ancestry estimates based on autosomal systems (genome-wide single-nucleotide polymorphisms and short tandem repeats). Finally, the comparison of paternal and maternal lineages provided additional information concerning the gender bias admixture, mating patterns, and population structure in Mestizos throughout the Mexican territory.

  15. Sulfate resistance of concrete containing high volume of mineral admixtures[ACI SP-234-37

    Energy Technology Data Exchange (ETDEWEB)

    Irassar, E.F. [Buenos Aires Central State Univ., Olavarria (Argentina). Dept. of Civil Engineering; Batic, O.R. [La Plata Univ., (Argentina)]|[Commission of Scientific Research of Buenos Aires (Argentina); Di Maio, A. [La Plata Technilogical Univ. (Argentina)]|[CONICET-LEMIT (Argentina); Ponce, J.M. [LEMIT-CIC (Argentina)]|[La Plata Univ. (Argentina). Faculty of Natural Sciences

    2006-07-01

    Various physical and chemical processes that influence the durability of concrete structures were discussed. For underground or on grade structures, the durability of concrete depends on the chemical composition of concrete and the concentration of ionic species present in the soil or groundwater, the permeability of soil, exposition to water, the flow of water, and the shape and size of structure. It also depends on the quality of concrete in terms of compaction, water to cementitious ratio, cementitious content, type of cementitious materials, and curing process. The rate and course of concrete deterioration also depends on environmental conditions such as low temperature, temperature cycles between day and night, and the relative humidity of ambient air. Durable foundations in a sulfate environment require a low permeability concrete in order to assure good compaction and curing procedures. The type of cementitious material is also important in preventing deterioration. This paper summarized 15 years of results related to the effect of high volume mineral admixtures on the sulfate resistance of concrete. A mechanism of concrete degradation was presented based on macroscopic and microscopic behaviour. The physical and chemical attack produced by sulfate soils was emphasized. The presentation outlined the materials used, mixture proportions, curing, exposure conditions, inspection, compressive strength test methods and microstructural analyses. It was shown that a combination of portland cement with a high volume of appropriate fly ash, natural pozzolan or granulated blast-furnace slag provides an excellent performance for concrete structures buried in harsh alkali sulfate soils. Concretes with high volume of mineral admixtures are more susceptible to the physical salt attack caused by cycles of wetting and drying that produce progressive scaling and mass loss. 21 refs., 3 tabs., 11 figs.

  16. Genetic origin, admixture, and asymmetry in maternal and paternal human lineages in Cuba

    Directory of Open Access Journals (Sweden)

    Martínez-Fuentes Antonio

    2008-07-01

    Full Text Available Abstract Background Before the arrival of Europeans to Cuba, the island was inhabited by two Native American groups, the Tainos and the Ciboneys. Most of the present archaeological, linguistic and ancient DNA evidence indicates a South American origin for these populations. In colonial times, Cuban Native American people were replaced by European settlers and slaves from Africa. It is still unknown however, to what extent their genetic pool intermingled with and was 'diluted' by the arrival of newcomers. In order to investigate the demographic processes that gave rise to the current Cuban population, we analyzed the hypervariable region I (HVS-I and five single nucleotide polymorphisms (SNPs in the mitochondrial DNA (mtDNA coding region in 245 individuals, and 40 Y-chromosome SNPs in 132 male individuals. Results The Native American contribution to present-day Cubans accounted for 33% of the maternal lineages, whereas Africa and Eurasia contributed 45% and 22% of the lineages, respectively. This Native American substrate in Cuba cannot be traced back to a single origin within the American continent, as previously suggested by ancient DNA analyses. Strikingly, no Native American lineages were found for the Y-chromosome, for which the Eurasian and African contributions were around 80% and 20%, respectively. Conclusion While the ancestral Native American substrate is still appreciable in the maternal lineages, the extensive process of population admixture in Cuba has left no trace of the paternal Native American lineages, mirroring the strong sexual bias in the admixture processes taking place during colonial times.

  17. Rapid frequency scan EPR.

    Science.gov (United States)

    Tseitlin, Mark; Rinard, George A; Quine, Richard W; Eaton, Sandra S; Eaton, Gareth R

    2011-08-01

    In rapid frequency scan EPR with triangular scans, sufficient time must be allowed to insure that the magnetization in the x, y plane decays to baseline at the end of the scan, which typically is about 5T(2) after the spins are excited. To permit relaxation of signals excited toward the extremes of the scan the total scan time required may be much longer than 5T(2). However, with periodic, saw-tooth excitation, the slow-scan EPR spectrum can be recovered by Fourier deconvolution of data recorded with a total scan period of 5T(2), even if some spins are excited later in the scan. This scan time is similar to polyphase excitation methods. The peak power required for either polyphase excitation or rapid frequency scans is substantially smaller than for pulsed EPR. The use of an arbitrary waveform generator (AWG) and cross loop resonator facilitated implementation of the rapid frequency scan experiments reported here. The use of constant continuous low B(1), periodic excitation waveform, and constant external magnetic field is similar to polyphase excitation, but could be implemented without the AWG that is required for polyphase excitation. PMID:21664848

  18. Line-scanning, stage scanning confocal microscope

    Science.gov (United States)

    Carucci, John A.; Stevenson, Mary; Gareau, Daniel

    2016-03-01

    We created a line-scanning, stage scanning confocal microscope as part of a new procedure: video assisted micrographic surgery (VAMS). The need for rapid pathological assessment of the tissue on the surface of skin excisions very large since there are 3.5 million new skin cancers diagnosed annually in the United States. The new design presented here is a confocal microscope without any scanning optics. Instead, a line is focused in space and the sample, which is flattened, is physically translated such that the line scans across its face in a direction perpendicular to the line its self. The line is 6mm long and the stage is capable of scanning 50 mm, hence the field of view is quite large. The theoretical diffraction-limited resolution is 0.7um lateral and 3.7um axial. However, in this preliminary report, we present initial results that are a factor of 5-7 poorer in resolution. The results are encouraging because they demonstrate that the linear array detector measures sufficient signal from fluorescently labeled tissue and also demonstrate the large field of view achievable with VAMS.

  19. 高性能混凝土复合剂性能及应用研究%Study on Properties and Application of High Performance Concrete Compound Admixture

    Institute of Scientific and Technical Information of China (English)

    程朝霞; 余永强; 彭小芹

    2013-01-01

      采用电镜扫描及能谱分析混凝土复合剂的组成,测试了复合剂减水率、强度和复合剂配制混凝土的工作性、力学性能及耐久性,并对使用该复合剂的大体积矿井建设混凝土温度分布进行了ANSYS模拟。结果表明,复合剂为富含SiO2、Al2O3矿物材料和有机物的复合物。复合剂掺量为10%时,配制的混凝土坍落度达到195 mm,1 d、3 d抗压强度可分别达到28 d的48%、78%。渗水高度比基准混凝土降低了49.7%,28 d声速提高了6.2%,回弹值提高了10.3%,孔隙率降低了54.7%,大体积混凝土1 d最高温度达到38℃,7 d时达到46℃,28 d下降到21℃。%Using scanning electron microscopy (SEM) and energy spectrum technology to analyze the composition of mine construction high-performance concrete compound admixture. The compound admixture work, mechanical properties and durability were tested and the mass mine construction concrete thermal field was simulated through finite element ANSYS package. The results showed that compound material composition, was rich in silica, aluminium oxide mineral materials and organic additive compound, wherein the optimal compound concrete compressive strength of 1 d and 3 d reached 28 d strength of 48%and 78%, respectively. Compared with the reference concrete, water penetration height reduced by 49.7%, 28 d velocity increased by 6.2%, rebound raised 10.3%, AC impedance testing porosity decreased by 54.7%, ANSYS simulation showed that the maximum temperature of mass concrete reached 38℃in 1 d, 46℃in 7 d, dropped to 21℃in 28 d.

  20. A Generic Procedure for the Assessment of the Effect of Concrete Admixtures on the Sorption of Radionuclides on Cement: Concept and Selected Results

    Energy Technology Data Exchange (ETDEWEB)

    Glaus, M.A.; Laube, A.; Van Loon, L.R

    2004-03-01

    A screening procedure is proposed for the assessment of the effect of concrete admixtures on the sorption of radionuclides by cement. The procedure is both broad and generic, and can thus be used as input for the assessment of concrete admixtures which might be used in the future. The experimental feasibility and significance of the screening procedure are tested using selected concrete admixtures: i.e. sulfonated naphthalene-formaldehyde condensates, lignosulfonates, and a plasticiser used at PSI for waste conditioning. The effect of these on the sorption properties of Ni(II), Eu(III) and Th(IV) in cement is investigated using crushed Hardened Cement Paste (HCP), as well as cement pastes prepared in the presence of these admixtures. Strongly adverse effects on the sorption of the radionuclides tested are observed only in single cases, and under extreme conditions: i.e. at high ratios of concrete admixtures to HCP, and at low ratios of HCP to cement pore water. Under realistic conditions, both radionuclide sorption and the sorption of isosaccharinic acid (a strong complexant produced in cement-conditioned wastes containing cellulose) remain unaffected by the presence of concrete admixtures, which can be explained by the sorption of them onto the HCP. The pore-water concentrations of the concrete admixtures tested are thereby reduced to levels at which the formation of radionuclide complexes is no longer of importance. Further, the Langmuir sorption model, proposed for the sorption of concrete admixtures on HCP, suggests that the HCP surface does not become saturated, at least for those concrete admixtures tested. (author)

  1. A Generic Procedure for the Assessment of the Effect of Concrete Admixtures on the Sorption of Radionuclides on Cement: Concept and Selected Results

    International Nuclear Information System (INIS)

    A screening procedure is proposed for the assessment of the effect of concrete admixtures on the sorption of radionuclides by cement. The procedure is both broad and generic, and can thus be used as input for the assessment of concrete admixtures which might be used in the future. The experimental feasibility and significance of the screening procedure are tested using selected concrete admixtures: i.e. sulfonated naphthalene-formaldehyde condensates, lignosulfonates, and a plasticiser used at PSI for waste conditioning. The effect of these on the sorption properties of Ni(II), Eu(III) and Th(IV) in cement is investigated using crushed Hardened Cement Paste (HCP), as well as cement pastes prepared in the presence of these admixtures. Strongly adverse effects on the sorption of the radionuclides tested are observed only in single cases, and under extreme conditions: i.e. at high ratios of concrete admixtures to HCP, and at low ratios of HCP to cement pore water. Under realistic conditions, both radionuclide sorption and the sorption of isosaccharinic acid (a strong complexant produced in cement-conditioned wastes containing cellulose) remain unaffected by the presence of concrete admixtures, which can be explained by the sorption of them onto the HCP. The pore-water concentrations of the concrete admixtures tested are thereby reduced to levels at which the formation of radionuclide complexes is no longer of importance. Further, the Langmuir sorption model, proposed for the sorption of concrete admixtures on HCP, suggests that the HCP surface does not become saturated, at least for those concrete admixtures tested. (author)

  2. Admixture analysis of stocked brown trout populations using mapped microsatellite DNA markers: indigenous trout persist in introgressed populations

    DEFF Research Database (Denmark)

    Hansen, Michael Møller; Mensberg, Karen-Lise Dons

    2009-01-01

    , but resolution is low if genetic differentiation is weak. Here, we analyse stocked brown trout populations represented by historical (1943-1956) and contemporary (2000s) samples, where genetic differentiation between wild populations and stocked trout is weak (pair-wise F-ST of 0.047 and 0.053). By...

  3. Mapping Quantitative Trait Loci (QTL in sheep. III. QTL for carcass composition traits derived from CT scans and aligned with a meta-assembly for sheep and cattle carcass QTL

    Directory of Open Access Journals (Sweden)

    Thomson Peter C

    2010-09-01

    Full Text Available Abstract An (Awassi × Merino × Merino single-sire backcross family with 165 male offspring was used to map quantitative trait loci (QTL for body composition traits on a framework map of 189 microsatellite loci across all autosomes. Two cohorts were created from the experimental progeny to represent alternative maturity classes for body composition assessment. Animals were raised under paddock conditions prior to entering the feedlot for a 90-day fattening phase. Body composition traits were derived in vivo at the end of the experiment prior to slaughter at 2 (cohort 1 and 3.5 (cohort 2 years of age, using computed tomography. Image analysis was used to gain accurate predictions for 13 traits describing major fat depots, lean muscle, bone, body proportions and body weight which were used for single- and two-QTL mapping analysis. Using a maximum-likelihood approach, three highly significant (LOD ≥ 3, 15 significant (LOD ≥ 2, and 11 suggestive QTL (1.7 ≤ LOD P P A meta-assembly of ovine QTL for carcass traits from this study and public domain sources was performed and compared with a corresponding bovine meta-assembly. The assembly demonstrated QTL with effects on carcass composition in homologous regions on OAR1, 2, 6 and 21.

  4. Mechanically scanned deployable antenna study

    Science.gov (United States)

    1983-03-01

    The conceptual design of a Mechanically Scanned Deployable Antenna which is launched by the STS (Space Shuttle) to provide radiometric brightness temperature maps of the Earth and oceans at selected frequency bands in the frequency range of 1.4 GHz to 11 GHz is presented. Unlike previous scanning radiometric systems, multiple radiometers for each frequency are required in order to fill in the resolution cells across the swath created by the 15 meter diameter spin stabilized system. This multiple beam radiometric system is sometimes designated as a ""whiskbroom'' system in that it combines the techniques of the scanning and ""pushbroom'' type systems. The definition of the feed system including possible feed elements and location, determination of the fundamental reflector feed offset geometry including offset angles and f/D ratio, preliminary estimates of the beam efficiency of the feed reflector system, a summary of reflector mesh losses at the proposed radiometric frequency bands, an overall conceptual configuration design and preliminary structural and thermal analyses are included.

  5. Radionucleotide scanning in osteomyelitis

    International Nuclear Information System (INIS)

    Radionucleotide bone scanning can be an excellent adjunct to the standard radiograph and clinical findings in the diagnosis of osteomyelitis. Bone scans have the ability to detect osteomyelitis far in advance of the standard radiograph. The sequential use of technetium and gallium has been useful in differentiating cellulitis and osteomyelitis. Serial scanning with technetium and gallium may be used to monitor the response of osteomyelitis to antibiotic therapy

  6. Mapping Quantitative Trait Loci (QTL) in sheep. III. QTL for carcass composition traits derived from CT scans and aligned with a meta-assembly for sheep and cattle carcass QTL.

    Science.gov (United States)

    Cavanagh, Colin R; Jonas, Elisabeth; Hobbs, Matthew; Thomson, Peter C; Tammen, Imke; Raadsma, Herman W

    2010-09-16

    An (Awassi × Merino) × Merino single-sire backcross family with 165 male offspring was used to map quantitative trait loci (QTL) for body composition traits on a framework map of 189 microsatellite loci across all autosomes. Two cohorts were created from the experimental progeny to represent alternative maturity classes for body composition assessment. Animals were raised under paddock conditions prior to entering the feedlot for a 90-day fattening phase. Body composition traits were derived in vivo at the end of the experiment prior to slaughter at 2 (cohort 1) and 3.5 (cohort 2) years of age, using computed tomography. Image analysis was used to gain accurate predictions for 13 traits describing major fat depots, lean muscle, bone, body proportions and body weight which were used for single- and two-QTL mapping analysis. Using a maximum-likelihood approach, three highly significant (LOD ≥ 3), 15 significant (LOD ≥ 2), and 11 suggestive QTL (1.7 ≤ LOD < 2) were detected on eleven chromosomes. Regression analysis confirmed 28 of these QTL and an additional 17 suggestive (P < 0.1) and two significant (P < 0.05) QTL were identified using this method. QTL with pleiotropic effects for two or more tissues were identified on chromosomes 1, 6, 10, 14, 16 and 23. No tissue-specific QTL were identified.A meta-assembly of ovine QTL for carcass traits from this study and public domain sources was performed and compared with a corresponding bovine meta-assembly. The assembly demonstrated QTL with effects on carcass composition in homologous regions on OAR1, 2, 6 and 21.

  7. Planetary maps

    Science.gov (United States)

    ,

    1992-01-01

    An important goal of the USGS planetary mapping program is to systematically map the geology of the Moon, Mars, Venus, and Mercury, and the satellites of the outer planets. These geologic maps are published in the USGS Miscellaneous Investigations (I) Series. Planetary maps on sale at the USGS include shaded-relief maps, topographic maps, geologic maps, and controlled photomosaics. Controlled photomosaics are assembled from two or more photographs or images using a network of points of known latitude and longitude. The images used for most of these planetary maps are electronic images, obtained from orbiting television cameras, various optical-mechanical systems. Photographic film was only used to map Earth's Moon.

  8. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Crushes What's a Booger? Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands for "computerized axial tomography." Translated, that ...

  9. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Here's Help White House Lunch Recipes Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands for "computerized axial tomography." Translated, that means ...

  10. Frequency scanning microstrip antennas

    DEFF Research Database (Denmark)

    Danielsen, Magnus; Jørgensen, Rolf

    1979-01-01

    The principles of using radiating microstrip resonators as elements in a frequency scanning antenna array are described. The resonators are cascade-coupled. This gives a scan of the main lobe due to the phase-shift in the resonator in addition to that created by the transmission line phase...

  11. Abdominal CT scan

    Science.gov (United States)

    ... than regular x-rays. Many x-rays or CT scans over time may increase your risk for cancer. However, the risk from any one scan is small. Talk to your doctor about this risk and the benefit of the test for getting a correct diagnosis ...

  12. Environmental Scanning Report.

    Science.gov (United States)

    Truckee Meadows Community Coll., Sparks, NV.

    This report describes Truckee Meadows Community College's (Nevada) environmental scanning process and results. The college decided that environmental scanning and forecasting techniques should be used to plan for both short-term and long-term external factors that impact programs, enrollment, and budgets. Strategic goals include: (1) keeping pace…

  13. Optical Scanning Applications.

    Science.gov (United States)

    Wagner, Hans

    The successful use of optical scanning at the University of the Pacific (UOP) indicates that such techniques can simplify a number of administrative data processing tasks. Optical scanning is regularly used at UOP to assist with data processing in the areas of admissions, registration and grade reporting and also has applications for other tasks…

  14. Knee CT scan

    Science.gov (United States)

    Risks of CT scans include: Exposure to radiation Allergy to contrast dye CT scans give off more radiation than ... injected contrast dye. The most common type of contrast contains ... you have this an iodine allergy. If you need to have this kind of ...

  15. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Dictionary of Medical Words En Español What Other Kids Are Reading Movie: Digestive System Winter Sports: Sledding, ... Booger? Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A ...

  16. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Skiing, Snowboarding, Skating Crushes What's a Booger? Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de ...

  17. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Snowboarding, Skating Crushes What's a Booger? Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands for "computerized axial tomography." Translated, that means ...

  18. Influence of the Type and Method of Injection of Oxides Admixtures of Rare Earth Elements on Colour and other Properties of Dental Porcelain

    Institute of Scientific and Technical Information of China (English)

    Ekaterina A. Kulinich; Tamara A. Khabas; Vladimir I. Vereschagin

    2010-01-01

    A glassceramic material, which can be used in stomatology for production of dentinal layer of the dental crown multilayer coating, was received. In order to colour the material the admixtures of Tb and Ce compounds were used, as well as composite admixture representing a mixture of Ce, Nd and La oxides. It was demonstrated that the admixture of Tb oxide tones the material only when it is used together with Ce oxide. It was found that the more admixtures of rare earth elements oxides are contained in the sample composition, the higher the colour strength of the sintered material is. The wave length for the test samples is in the range of 600~650 nm, which corresponds to the yellow-orange and orange-red spectral range.

  19. Influence of the calcium concentration in the presence of organic phosphorus on the physicochemical compatibility and stability of all-in-one admixtures for neonatal use

    Directory of Open Access Journals (Sweden)

    de Sousa Valeria

    2009-10-01

    Full Text Available Abstract Background Preterm infants need high amounts of calcium and phosphorus for bone mineralization, which is difficult to obtain with parenteral feeding due to the low solubility of these salts. The objective of this study was to evaluate the physicochemical compatibility of high concentrations of calcium associated with organic phosphate and its influence on the stability of AIO admixtures for neonatal use. Methods Three TPN admixture formulas were prepared in multilayered bags. The calcium content of the admixtures was adjusted to 0, 46.5 or 93 mg/100 ml in the presence of a fixed organic phosphate concentration as well as lipids, amino acids, inorganic salts, glucose, vitamins and oligoelements at pH 5.5. Each admixture was stored at 4°C, 25°C or 37°C and evaluated over a period of 7 days. The physicochemical stability parameters evaluated were visual aspect, pH, sterility, osmolality, peroxide formation, precipitation, and the size of lipid globules. Results Color alterations occurred from the first day on, and reversible lipid film formation from the third day of study for the admixtures stored at 25°C and 37°C. According to the parameters evaluated, the admixtures were stable at 4°C; and none of them presented precipitated particles due to calcium/phosphate incompatibility or lipid globules larger than 5 μm, which is the main parameter currently used to evaluate lipid emulsion stability. The admixtures maintained low peroxide levels and osmolarity was appropriate for parenteral administration. Conclusion The total calcium and calcium/phosphorus ratios studied appeared not to influence the physicochemical compatibility and stability of AIO admixtures.

  20. Nuclear species-diagnostic SNP markers mined from 454 amplicon sequencing reveal admixture genomic structure of modern citrus varieties.

    Directory of Open Access Journals (Sweden)

    Franck Curk

    Full Text Available Most cultivated Citrus species originated from interspecific hybridisation between four ancestral taxa (C. reticulata, C. maxima, C. medica, and C. micrantha with limited further interspecific recombination due to vegetative propagation. This evolution resulted in admixture genomes with frequent interspecific heterozygosity. Moreover, a major part of the phenotypic diversity of edible citrus results from the initial differentiation between these taxa. Deciphering the phylogenomic structure of citrus germplasm is therefore essential for an efficient utilization of citrus biodiversity in breeding schemes. The objective of this work was to develop a set of species-diagnostic single nucleotide polymorphism (SNP markers for the four Citrus ancestral taxa covering the nine chromosomes, and to use these markers to infer the phylogenomic structure of secondary species and modern cultivars. Species-diagnostic SNPs were mined from 454 amplicon sequencing of 57 gene fragments from 26 genotypes of the four basic taxa. Of the 1,053 SNPs mined from 28,507 kb sequence, 273 were found to be highly diagnostic for a single basic taxon. Species-diagnostic SNP markers (105 were used to analyse the admixture structure of varieties and rootstocks. This revealed C. maxima introgressions in most of the old and in all recent selections of mandarins, and suggested that C. reticulata × C. maxima reticulation and introgression processes were important in edible mandarin domestication. The large range of phylogenomic constitutions between C. reticulata and C. maxima revealed in mandarins, tangelos, tangors, sweet oranges, sour oranges, grapefruits, and orangelos is favourable for genetic association studies based on phylogenomic structures of the germplasm. Inferred admixture structures were in agreement with previous hypotheses regarding the origin of several secondary species and also revealed the probable origin of several acid citrus varieties. The developed species

  1. Nuclear species-diagnostic SNP markers mined from 454 amplicon sequencing reveal admixture genomic structure of modern citrus varieties.

    Science.gov (United States)

    Curk, Franck; Ancillo, Gema; Ollitrault, Frédérique; Perrier, Xavier; Jacquemoud-Collet, Jean-Pierre; Garcia-Lor, Andres; Navarro, Luis; Ollitrault, Patrick

    2015-01-01

    Most cultivated Citrus species originated from interspecific hybridisation between four ancestral taxa (C. reticulata, C. maxima, C. medica, and C. micrantha) with limited further interspecific recombination due to vegetative propagation. This evolution resulted in admixture genomes with frequent interspecific heterozygosity. Moreover, a major part of the phenotypic diversity of edible citrus results from the initial differentiation between these taxa. Deciphering the phylogenomic structure of citrus germplasm is therefore essential for an efficient utilization of citrus biodiversity in breeding schemes. The objective of this work was to develop a set of species-diagnostic single nucleotide polymorphism (SNP) markers for the four Citrus ancestral taxa covering the nine chromosomes, and to use these markers to infer the phylogenomic structure of secondary species and modern cultivars. Species-diagnostic SNPs were mined from 454 amplicon sequencing of 57 gene fragments from 26 genotypes of the four basic taxa. Of the 1,053 SNPs mined from 28,507 kb sequence, 273 were found to be highly diagnostic for a single basic taxon. Species-diagnostic SNP markers (105) were used to analyse the admixture structure of varieties and rootstocks. This revealed C. maxima introgressions in most of the old and in all recent selections of mandarins, and suggested that C. reticulata × C. maxima reticulation and introgression processes were important in edible mandarin domestication. The large range of phylogenomic constitutions between C. reticulata and C. maxima revealed in mandarins, tangelos, tangors, sweet oranges, sour oranges, grapefruits, and orangelos is favourable for genetic association studies based on phylogenomic structures of the germplasm. Inferred admixture structures were in agreement with previous hypotheses regarding the origin of several secondary species and also revealed the probable origin of several acid citrus varieties. The developed species-diagnostic SNP

  2. On the use of crystalline admixtures in cement based construction materials: from porosity reducers to promoters of self healing

    Science.gov (United States)

    Ferrara, Liberato; Krelani, Visar; Moretti, Fabio

    2016-08-01

    The project detailed in this paper aims at a thorough characterization of the effects of crystalline admixtures, currently employed as porosity reducing admixtures, on the self-healing capacity of the cementitious composites, i.e. their capacity to completely or partially re-seal cracks and, in case, also exhibit recovery of mechanical properties. The problem has been investigated with reference to both a normal strength concrete (NSC) and a high performance fibre reinforced cementitious composite (HPFRCC). In the latter case, the influence of flow-induced fibre alignment has also been considered in the experimental investigation. With reference to either 3-point (for NSC) or 4-point (for HPFRCC) bending tests performed up to controlled crack opening and up to failure, respectively before and after exposure/conditioning recovery of stiffness and stress bearing capacity has been evaluated to assess the self-healing capacity. In a durability-based design framework, self-healing indices to quantify the recovery of mechanical properties will also be defined. In NSC, crystalline admixtures are able to promote up to 60% of crack sealing even under exposure to open air. In the case of HPFRCCs, which would already feature autogenous healing capacity because of their peculiar mix compositions, the synergy between the dispersed fibre reinforcement and the action of the crystalline admixture has resulted in a likely ‘chemical pre-stressing’ of the same reinforcement, from which the recovery of mechanical performance of the material has greatly benefited, up to levels even higher than the performance of the virgin un-cracked material.

  3. Cuba: exploring the history of admixture and the genetic basis of pigmentation using autosomal and uniparental markers.

    Science.gov (United States)

    Marcheco-Teruel, Beatriz; Parra, Esteban J; Fuentes-Smith, Evelyn; Salas, Antonio; Buttenschøn, Henriette N; Demontis, Ditte; Torres-Español, María; Marín-Padrón, Lilia C; Gómez-Cabezas, Enrique J; Alvarez-Iglesias, Vanesa; Mosquera-Miguel, Ana; Martínez-Fuentes, Antonio; Carracedo, Angel; Børglum, Anders D; Mors, Ole

    2014-07-01

    We carried out an admixture analysis of a sample comprising 1,019 individuals from all the provinces of Cuba. We used a panel of 128 autosomal Ancestry Informative Markers (AIMs) to estimate the admixture proportions. We also characterized a number of haplogroup diagnostic markers in the mtDNA and Y-chromosome in order to evaluate admixture using uniparental markers. Finally, we analyzed the association of 16 single nucleotide polymorphisms (SNPs) with quantitative estimates of skin pigmentation. In the total sample, the average European, African and Native American contributions as estimated from autosomal AIMs were 72%, 20% and 8%, respectively. The Eastern provinces of Cuba showed relatively higher African and Native American contributions than the Western provinces. In particular, the highest proportion of African ancestry was observed in the provinces of Guantánamo (40%) and Santiago de Cuba (39%), and the highest proportion of Native American ancestry in Granma (15%), Holguín (12%) and Las Tunas (12%). We found evidence of substantial population stratification in the current Cuban population, emphasizing the need to control for the effects of population stratification in association studies including individuals from Cuba. The results of the analyses of uniparental markers were concordant with those observed in the autosomes. These geographic patterns in admixture proportions are fully consistent with historical and archaeological information. Additionally, we identified a sex-biased pattern in the process of gene flow, with a substantially higher European contribution from the paternal side, and higher Native American and African contributions from the maternal side. This sex-biased contribution was particularly evident for Native American ancestry. Finally, we observed that SNPs located in the genes SLC24A5 and SLC45A2 are strongly associated with melanin levels in the sample.

  4. The ion-selective field-effect transistor application for enzyme analysis of toxic admixtures in aqueous solutions

    Directory of Open Access Journals (Sweden)

    Pavluchenko A. S.

    2010-06-01

    Full Text Available The article describes design and production technology of pH-sensors based on ion-selective field-effect transis-tors (ISFET intended for enzyme analysis of inhibiting admixtures in aqueous solutions, and architecture of the multichannel measuring system built upon the ISFET-sensors. The characteristics of developed prototypes are given and the ways for further improvement of system design, metrological performance and operating parameters are outlined.

  5. Cuba: exploring the history of admixture and the genetic basis of pigmentation using autosomal and uniparental markers.

    Science.gov (United States)

    Marcheco-Teruel, Beatriz; Parra, Esteban J; Fuentes-Smith, Evelyn; Salas, Antonio; Buttenschøn, Henriette N; Demontis, Ditte; Torres-Español, María; Marín-Padrón, Lilia C; Gómez-Cabezas, Enrique J; Alvarez-Iglesias, Vanesa; Mosquera-Miguel, Ana; Martínez-Fuentes, Antonio; Carracedo, Angel; Børglum, Anders D; Mors, Ole

    2014-07-01

    We carried out an admixture analysis of a sample comprising 1,019 individuals from all the provinces of Cuba. We used a panel of 128 autosomal Ancestry Informative Markers (AIMs) to estimate the admixture proportions. We also characterized a number of haplogroup diagnostic markers in the mtDNA and Y-chromosome in order to evaluate admixture using uniparental markers. Finally, we analyzed the association of 16 single nucleotide polymorphisms (SNPs) with quantitative estimates of skin pigmentation. In the total sample, the average European, African and Native American contributions as estimated from autosomal AIMs were 72%, 20% and 8%, respectively. The Eastern provinces of Cuba showed relatively higher African and Native American contributions than the Western provinces. In particular, the highest proportion of African ancestry was observed in the provinces of Guantánamo (40%) and Santiago de Cuba (39%), and the highest proportion of Native American ancestry in Granma (15%), Holguín (12%) and Las Tunas (12%). We found evidence of substantial population stratification in the current Cuban population, emphasizing the need to control for the effects of population stratification in association studies including individuals from Cuba. The results of the analyses of uniparental markers were concordant with those observed in the autosomes. These geographic patterns in admixture proportions are fully consistent with historical and archaeological information. Additionally, we identified a sex-biased pattern in the process of gene flow, with a substantially higher European contribution from the paternal side, and higher Native American and African contributions from the maternal side. This sex-biased contribution was particularly evident for Native American ancestry. Finally, we observed that SNPs located in the genes SLC24A5 and SLC45A2 are strongly associated with melanin levels in the sample. PMID:25058410

  6. Effect of Expansive Admixtures on the Shrinkage and Mechanical Properties of High-Performance Fiber-Reinforced Cement Composites

    OpenAIRE

    Won-Chang Choi; Hyun-Do Yun

    2013-01-01

    High-performance fiber-reinforced cement composites (HPFRCCs) are characterized by strain-hardening and multiple cracking during the inelastic deformation process, but they also develop high shrinkage strain. This study investigates the effects of replacing Portland cement with calcium sulfoaluminate-based expansive admixtures (CSA EXAs) to compensate for the shrinkage and associated mechanical behavior of HPFRCCs. Two types of CSA EXA (CSA-K and CSA-J), each with a different chemical composi...

  7. Cuba: exploring the history of admixture and the genetic basis of pigmentation using autosomal and uniparental markers.

    Directory of Open Access Journals (Sweden)

    Beatriz Marcheco-Teruel

    2014-07-01

    Full Text Available We carried out an admixture analysis of a sample comprising 1,019 individuals from all the provinces of Cuba. We used a panel of 128 autosomal Ancestry Informative Markers (AIMs to estimate the admixture proportions. We also characterized a number of haplogroup diagnostic markers in the mtDNA and Y-chromosome in order to evaluate admixture using uniparental markers. Finally, we analyzed the association of 16 single nucleotide polymorphisms (SNPs with quantitative estimates of skin pigmentation. In the total sample, the average European, African and Native American contributions as estimated from autosomal AIMs were 72%, 20% and 8%, respectively. The Eastern provinces of Cuba showed relatively higher African and Native American contributions than the Western provinces. In particular, the highest proportion of African ancestry was observed in the provinces of Guantánamo (40% and Santiago de Cuba (39%, and the highest proportion of Native American ancestry in Granma (15%, Holguín (12% and Las Tunas (12%. We found evidence of substantial population stratification in the current Cuban population, emphasizing the need to control for the effects of population stratification in association studies including individuals from Cuba. The results of the analyses of uniparental markers were concordant with those observed in the autosomes. These geographic patterns in admixture proportions are fully consistent with historical and archaeological information. Additionally, we identified a sex-biased pattern in the process of gene flow, with a substantially higher European contribution from the paternal side, and higher Native American and African contributions from the maternal side. This sex-biased contribution was particularly evident for Native American ancestry. Finally, we observed that SNPs located in the genes SLC24A5 and SLC45A2 are strongly associated with melanin levels in the sample.

  8. Nuclear species-diagnostic SNP markers mined from 454 amplicon sequencing reveal admixture genomic structure of modern citrus varieties.

    Science.gov (United States)

    Curk, Franck; Ancillo, Gema; Ollitrault, Frédérique; Perrier, Xavier; Jacquemoud-Collet, Jean-Pierre; Garcia-Lor, Andres; Navarro, Luis; Ollitrault, Patrick

    2015-01-01

    Most cultivated Citrus species originated from interspecific hybridisation between four ancestral taxa (C. reticulata, C. maxima, C. medica, and C. micrantha) with limited further interspecific recombination due to vegetative propagation. This evolution resulted in admixture genomes with frequent interspecific heterozygosity. Moreover, a major part of the phenotypic diversity of edible citrus results from the initial differentiation between these taxa. Deciphering the phylogenomic structure of citrus germplasm is therefore essential for an efficient utilization of citrus biodiversity in breeding schemes. The objective of this work was to develop a set of species-diagnostic single nucleotide polymorphism (SNP) markers for the four Citrus ancestral taxa covering the nine chromosomes, and to use these markers to infer the phylogenomic structure of secondary species and modern cultivars. Species-diagnostic SNPs were mined from 454 amplicon sequencing of 57 gene fragments from 26 genotypes of the four basic taxa. Of the 1,053 SNPs mined from 28,507 kb sequence, 273 were found to be highly diagnostic for a single basic taxon. Species-diagnostic SNP markers (105) were used to analyse the admixture structure of varieties and rootstocks. This revealed C. maxima introgressions in most of the old and in all recent selections of mandarins, and suggested that C. reticulata × C. maxima reticulation and introgression processes were important in edible mandarin domestication. The large range of phylogenomic constitutions between C. reticulata and C. maxima revealed in mandarins, tangelos, tangors, sweet oranges, sour oranges, grapefruits, and orangelos is favourable for genetic association studies based on phylogenomic structures of the germplasm. Inferred admixture structures were in agreement with previous hypotheses regarding the origin of several secondary species and also revealed the probable origin of several acid citrus varieties. The developed species-diagnostic SNP

  9. Genetic dating indicates that the Asian–Papuan admixture through Eastern Indonesia corresponds to the Austronesian expansion

    OpenAIRE

    Xu, Shuhua; Pugach, Irina; Stoneking, Mark; Kayser, Manfred; Jin, Li

    2012-01-01

    Although the Austronesian expansion had a major impact on the languages of Island Southeast Asia, controversy still exists over the genetic impact of this expansion. The coexistence of both Asian and Papuan genetic ancestry in Eastern Indonesia provides a unique opportunity to address this issue. Here, we estimate recombination breakpoints in admixed genomes based on genome-wide SNP data and date the genetic admixture between populations of Asian vs. Papuan ancestry in Eastern Indonesia. Anal...

  10. The Influence of Mineral Admixtures on Bending Strength of Mortar on the Premise of Equal Compressive Strength

    Institute of Scientific and Technical Information of China (English)

    WANG Qiang; YAN Peiyu; FENG Jianwen

    2012-01-01

    The influence of mineral admixtures on bending strength of mortar on the premise of equal compressive strength was investigated.Three mineral admixtures (fly ash,ground granulated blast-furnace slag and steel slag) were used.The adding amount of mineral admixture in this study ranges from 22.5% to 60%,and the water-to-binder ratio ranges from 0.34 to 0.50.With equal compressive strength,different mortars can be arranged in such a descending order with their bending strength:cement-fly ash mortar,cement mortar,cement-GGBS mortar,and cement-steel slag mortar.With the same compressive strength,the higher the steel slag content and water-to-binder ratio,the lower the bending strength of mortars.However,the effect of mineral mixture content and water-to-binder ratio on the bending strength of cement-fly ash mortar and cement-GGBS mortar is far inconspicuous.

  11. Testing models of speciation from genome sequences: divergence and asymmetric admixture in Island South-East Asian Sus species during the Plio-Pleistocene climatic fluctuations.

    Science.gov (United States)

    Frantz, Laurent A F; Madsen, Ole; Megens, Hendrik-Jan; Groenen, Martien A M; Lohse, Konrad

    2014-11-01

    In many temperate regions, ice ages promoted range contractions into refugia resulting in divergence (and potentially speciation), while warmer periods led to range expansions and hybridization. However, the impact these climatic oscillations had in many parts of the tropics remains elusive. Here, we investigate this issue using genome sequences of three pig (Sus) species, two of which are found on islands of the Sunda-shelf shallow seas in Island South-East Asia (ISEA). A previous study revealed signatures of interspecific admixture between these Sus species (Genome biology, 14, 2013, R107). However, the timing, directionality and extent of this admixture remain unknown. Here, we use a likelihood-based model comparison to more finely resolve this admixture history and test whether it was mediated by humans or occurred naturally. Our analyses suggest that interspecific admixture between Sunda-shelf species was most likely asymmetric and occurred long before the arrival of humans in the region. More precisely, we show that these species diverged during the late Pliocene but around 23% of their genomes have been affected by admixture during the later Pleistocene climatic transition. In addition, we show that our method provides a significant improvement over D-statistics which are uninformative about the direction of admixture. PMID:25294645

  12. Scanning with Iodine-125

    International Nuclear Information System (INIS)

    The use of I125 as I125-iodide for scanning of the thyroid and of thyroid carcinoma métastasés and as I125-labelled Rose Bengal for scanning of the liver has been investigated in our laboratories. In some patients, the thyroid scans and the scans of thyroid carcinoma metastases were repeated with I131. The liver scans were repeated with colloidal Au198. Cold nodules in the thyroid which could not be detected with I131 were clearly seen with I125. Anterior métastasés in the lungs could be differentiated from posterior métastasés with I125, while with I131 this was not possible. Using the same doses of radioactivity the background with I131 was much higher and could not be eliminated, as this would have reduced the counting rate over the lesions to levels which could not be detected. Some of the photoscans and mechanical scans of livers carried out with colloidal Au198 could not be interpreted. However, ''cold'' lesions were clearly seen on the scans of the same livers with I125-labelled Rose Bengal. (author)

  13. Genetics, surnames, grandparents' nationalities, and ethnic admixture in Southern Brazil: Do the patterns of variation coincide?

    Directory of Open Access Journals (Sweden)

    Dornelles C.L.

    1999-01-01

    Full Text Available A total of 2,708 individuals from the European-derived population of Rio Grande do Sul, divided into seven mesoregions, and of 226 individuals of similar origin from Santa Catarina were studied. Seventeen protein genetic systems, as well as grandparents' nationalities, individuals' surnames, and interethnic admixture were investigated. The alleles which presented the highest and lowest differences were GLO1*2 (16% and PGD*A (2%, respectively, but in general no significant genetic differences were found among mesoregions. The values observed were generally those expected for individuals of European descent, with the largest difference being a lower prevalence (34-39% of P*1. Significant heterogeneity among mesoregions was observed for the other variables considered, and was consistent with historical records. The Amerindian contribution to the gene pool of European-derived subjects in Rio Grande do Sul was estimated to be as high as 11%. Based on the four data sets, the most general finding was a tendency for a northeast-southwest separation of the populations studied. Seven significant phenotype associations between systems were observed at the 5% level (three at the 0.1% level. Of the latter, the two most interesting (since they were also observed in other studies were MNSs/Duffy and Rh/ACP.

  14. The E2 admixtures in mixed forbidden lines of Bi I and Pb I

    Energy Technology Data Exchange (ETDEWEB)

    Wasowicz, T J [Institute of Experimental Physics, University of Gdansk, ul. Wita Stwosza 57, 80-952 Gdansk (Poland)

    2007-10-15

    The hyperfine structures (hfs) of mixed (M1+E2) multipole lines 461.5 nm (6p{sup 3} {sup 2}P{sub 1/2}{yields}6p{sup 3} {sup 4}S{sub 3/2}) and 647.6 nm (6p{sup 3} {sup 2}D{sub 5/2}{yields}6p{sup 3} {sup 4}S{sub 3/2}) of Bi I and 733.2 nm (6p{sup 2} {sup 1}D{sub 2}{yields}6p{sup 2} {sup 3}P{sub 1}) of Pb I are presented. A computer modelling technique was used to obtain the predicted hfs contours of these lines. By varying the free parameters describing the line shape and the electric-quadrupole admixture D{sup E2} the calculated profiles were fitted to the recorded spectra. The D{sup E2} values obtained from the best fits were found to be (7.3{+-}0.9), (17.6{+-}1.2) and (5.0{+-}0.6)% for the 461.5, 647.6 and 733.2 nm lines, respectively. These results are compared with other experiments and recent theories.

  15. Genetics, surnames, grandparents' nationalities, and ethnic admixture in Southern Brazil: Do the patterns of variation coincide?

    Directory of Open Access Journals (Sweden)

    C.L. Dornelles

    1999-06-01

    Full Text Available A total of 2,708 individuals from the European-derived population of Rio Grande do Sul, divided into seven mesoregions, and of 226 individuals of similar origin from Santa Catarina were studied. Seventeen protein genetic systems, as well as grandparents' nationalities, individuals' surnames, and interethnic admixture were investigated. The alleles which presented the highest and lowest differences were GLO1*2 (16% and PGD*A (2%, respectively, but in general no significant genetic differences were found among mesoregions. The values observed were generally those expected for individuals of European descent, with the largest difference being a lower prevalence (34-39% of P*1. Significant heterogeneity among mesoregions was observed for the other variables considered, and was consistent with historical records. The Amerindian contribution to the gene pool of European-derived subjects in Rio Grande do Sul was estimated to be as high as 11%. Based on the four data sets, the most general finding was a tendency for a northeast-southwest separation of the populations studied. Seven significant phenotype associations between systems were observed at the 5% level (three at the 0.1% level. Of the latter, the two most interesting (since they were also observed in other studies were MNSs/Duffy and Rh/ACP.

  16. Influence of CG With High Content of Metallic Particles as a Cement Admixture on Cement Strength

    Institute of Scientific and Technical Information of China (English)

    WAN Hui-wen; LIN Zong-shou; ZHAO Qian; HUANG Yun

    2003-01-01

    Copper gangue (CG), containing a large amount of water with grain sizes of 0.037 to 0.10mm,is an inactive industrial waste generated from copper refineries. When it is dried and used as a cement admixture, the influence of the presence of finely dispersed metallic particles in CG on the microstructure and compressive strength of cement paste has been studied.The results show that the higher the replacement of CG is,the lower the compressive strength of cement mortar is.However,the long-term strength of the specimens with 10% CG,especially after being cured for 3 months,approached to that of the plain mortar.Its mechanism was studied by an electron probe X-ray microanalyzer (EPXMA).The results indicate that a small quantity of Fe(OH)3·nH2O slowly formed from Fe2O3 in the presence of Ca(OH)2, free CaO and MgO of the clinker also slowly hydrated and formed Ca(OH)2 and Mg(OH)2 respectively,so the hardened cement paste became more compact.

  17. Efficiency of the coherent biexciton admixture mechanism for multiple exciton generation in InAs nanocrystals

    International Nuclear Information System (INIS)

    We study the coherent mixing between two-particle (single exciton) and four-particle (biexciton) states of a semiconductor nanocrystal resulting from the Coulomb coupling between states with different numbers of electron-hole pairs. Using a simple model of the nanocrystal wave functions and an envelope function approach, we estimate the efficiency of the multiple exciton generation (MEG) process resulting from such coherent admixture mechanism, including all the relevant states in a very broad energy interval. We show that in a typical ensemble of nanocrystals with an average radius of 3nm, the onset of the MEG process appears about 1 eV above the lower edge of the biexciton density of states. This is due to the angular momentum conservation that imposes selection rules and limits the available MEG pathways, thus taking over the role of momentum conservation that hinders this process in bulk. The efficiency of the MEG process reaches 50% for photon energies around 5 eV. The MEG onset shifts to lower energies and therefore the efficiency increases in a certain energy range as the radius grows. The energy dependence of the MEG efficiency differs considerably between ensembles with small and large inhomogeneity of nanocrystal sizes. (paper)

  18. Genetic structure of marine Borrelia garinii and population admixture with the terrestrial cycle of Lyme borreliosis.

    Science.gov (United States)

    Gómez-Díaz, Elena; Boulinier, Thierry; Sertour, Natacha; Cornet, Muriel; Ferquel, Elisabeth; McCoy, Karen D

    2011-09-01

    Despite the importance of population structure for the epidemiology of pathogenic bacteria, the spatial and ecological heterogeneity of these populations is often poorly characterized. Here, we investigated the genetic diversity and population structure of the Lyme borreliosis (LB) spirochaete Borrelia garinii in its marine cycle involving colonial seabirds and different host races of the seabird tick Ixodes uriae. Multilocus sequence analyses (MLSA) on eight chromosomal and two plasmid loci (ospA and ospC) indicate that B. garinii circulating in the marine system is highly diverse. Microevolution in marine B. garinii seems to be mainly clonal, but recombination and selection do occur. Sequence types were not evenly distributed among geographic regions, with substantial population subdivision between Atlantic and Pacific Ocean basins. However, no geographic structuring was evident within regions. Results of selection analyses and phylogenetic discordance between chromosomal and plasmid loci indicate adaptive evolution is likely occurring in this system, but no pattern of host or vector-associated divergence was found. Recombination analyses showed evidence for population admixture between terrestrial and marine strains, suggesting that LB spirochaetes are exchanged between these enzootic cycles. Importantly, our results highlight the need to explicitly consider the marine system for a complete understanding of the evolutionary ecology and global epidemiology of Lyme borreliosis. PMID:21651685

  19. Total nutrient admixtures (3-in-1): pros vs cons for adults.

    Science.gov (United States)

    Gervasio, Jane

    2015-06-01

    Total nutrient admixture (TNA) is a complete parenteral nutrition (PN) formulation composed of all macronutrients, including dextrose, amino acids, and intravenous fat emulsions (IVFE), in one bag. The TNA may be safely administered to the patient, with all components aseptically compounded and minimal administration manipulation required, lending itself to decreases in risks of catheter contamination and patient infections. The TNA is compatible and stable at recommended concentrations, and since the IVFE is in the TNA, it is infused at slower rates, allowing for better fat clearance. The TNA offers convenience of administration and a potential cost savings to the healthcare institution both directly and indirectly. Unfortunately, the TNA is not without concerns. At low macronutrient concentrations (lower than recommended), the formulation is compromised. Greater divalent and monovalent cation amounts and increased concentrations of phosphate and calcium may destabilize the TNA or result in precipitation, respectively. With the addition of IVFE in the TNA, catheter occlusion is greater and larger pore size filters are necessary, resulting in less microbial elimination. Determining if the implementation of the TNA is appropriate for an institution requires a recognition of the advantages and disadvantages of the TNA as well as an understanding of the institution's patient population and their nutrition requirements. PMID:25855093

  20. USE OF CERTAIN ADMIXTURES IN THE CONSTRUCTION OF PAVEMENT ON EXPANSIVE CLAYEY SUBGRADES

    Directory of Open Access Journals (Sweden)

    D.NEERAJA,

    2010-11-01

    Full Text Available Due to rapid industrialization throughout the world, the production of huge quantity of produced waste materials creates not only the environmental problem but also the depositional hazards. Many procedures have been developed to improve the mechanical properties of soil by incorporating a wide range of stabilizing agents, additives and conditioners. In this paper, an attempt has been made to utilize industrial wastes like Rice Husk Ash (RHA, Fly Ash (FA and Ground Granulated Blast furnace Slag (GGBS as stabilizing agents. In addition to these, Lime was also added as stabilizing agent. The effect of Lime, RHA, FA and GGBS on certain properties of soil such as Optimum moisture content (OMC, Maximum Dry Density(MDD, Unconfined Compressive Strength (UCS and California Bearing Ratio (CBR has been studied. It has been established by experiments conducted on the samples that there is a maximum change in the properties with addition of lime up to 5%, RHA and GGBS up to 15% per cent and FA up to 20%. Of all the admixtures, Lime shows considerable increase in strength characteristics at an optimum lime content of 5% which gave maximum.

  1. Use of admixtures in organic-contaminated cement-clay pastes.

    Science.gov (United States)

    Gallo Stampino, Paola; Zampori, Luca; Dotelli, Giovanni; Meloni, Paola; Sora, Isabella Natali; Pelosato, Renato

    2009-01-30

    In this work microstructure, porosity and hydration degree of cement-based solidified/stabilized wasteforms were studied before assessing their leaching behaviour. 2-Chloroaniline was chosen as a model liquid organic pollutant and included into cement pastes, which were also modified with different admixtures for concrete: a superplasticizer based on acrylic-modified polymer, a synthetic rubber latex and a waterproofing agent. An organoclay, modified with an ammonium quaternary salt (benzyl-dimethyl-tallowammonium, BDMTA), was added to the pastes as pre-sorbent agent of the organic matter. All the samples were dried up to constant weight in order to stop the hydration process at different times during the first 28 days of curing, typically, after 1 day (1d), 7 days (7d) and 28 days. Then, the microstructure of the hardened cement-clay pastes was investigated by powder X-ray diffraction (XRD). The hydration degree and porosity were studied by thermal analysis (TG/DTA) and mercury intrusion porosimetry (MIP), respectively. For samples cured for 28 days a short-term leach test set by Italian regulation for industrial waste recycling (D.M. 5 February 1998) was performed. The best results showed a 5% release of the total initial amount of organic pollutant. PMID:18514398

  2. Admixture between native and invasive populations may increase invasiveness of Mimulus guttatus.

    Science.gov (United States)

    van Kleunen, Mark; Röckle, Michael; Stift, Marc

    2015-09-22

    Self-fertilization and admixture of genotypes from different populations can have major fitness consequences in native species. However, few studies have addressed their potential roles in invasive species. Here, we used plants of Mimulus guttatus from seven native North American, three invasive Scottish and four invasive New Zealand populations to address this. We created seeds from self-fertilization, within-population outcrossing, between-population outcrossing within the same range, and outcrossing between the native and invasive ranges. A greenhouse experiment showed that native and invasive plants of M. guttatus suffered to similar degrees from inbreeding depression, in terms of asexual reproduction and biomass production. After outcrossing with plants from other populations, M. guttatus benefited from heterosis, in terms of asexual and sexual reproduction, and biomass production, particularly when plants from native and invasive populations were crossed. This suggests that, when novel genotypes of M. guttatus from the native North American range will be introduced to the invasive ranges, subsequent outcrossing with M. guttatus plants that are already there might further boost invasiveness of this species.

  3. Binding Materials of Dehydrated Phases of Waste Hardened Cement Paste and Pozzolanic Admixture

    Institute of Scientific and Technical Information of China (English)

    LU Linnu; HE Yongjia; HU Shuguang

    2009-01-01

    Fly ash (FA) and ground granulated blast-furnace slag (GGBFS) were added to improve the performances of regenerated binding materials (RBM) which refer to dehydrated phases with rebinding ability of waste hardened cement paste. Flowability tests, compressive strength tests,SEM, TG-DSC, and non-evaporable water content tests were employed to study the performances of the combined binding materials and the interactions between RBM, FA, and GGBFS. Results show that adding FA or GGBFS can improve the workability of RBM paste, and GGBFS has positive effects on strength of RBM. Pozzolanic reactions happen between RBM, FA, and GGBFS. And the activation effect of RBM to FA and GGBFS is superior to that of P.O grade-32.5 cement, especially at earlier ages, because of the high reactive f-CaO existing in RBM. On the advantages of the synergetic effects of RBM and pozzolanic admixtures such as FA and GGBFS, new combined binding materials can be prepared by blending them together.

  4. Utilization of water-reducing admixtures in cemented paste backfill of sulphide-rich mill tailings.

    Science.gov (United States)

    Ercikdi, Bayram; Cihangir, Ferdi; Kesimal, Ayhan; Deveci, Haci; Alp, Ibrahim

    2010-07-15

    This study presents the effect of three different water-reducing admixtures (WRAs) on the rheological and mechanical properties of cemented paste backfill (CPB) samples. A 28-day strength of > or = 0.7 MPa and the maintenance of the stability (i.e. > or = 0.7 MPa) over 360 days of curing were desired as the design criteria. Ordinary Portland cement (OPC) and Portland composite cement (PCC) were used as binders at 5 wt.% dose. WRAs were initially tested to determine the dosage of a WRA for a required consistency of 7'' for CPB mixtures. A total of 192 CPB samples were then prepared using WRAs. The utilization of WRAs enhanced the flow characteristics of the CPB mixture and allowed to achieve the same consistency at a lower water-to-cement ratio. For OPC, the addition of WRAs appeared to improve the both short- and long-term performance of CPB samples. However, only polycarboxylate-based superplasticiser produced the desired 28-day strength of > or = 0.7 MPa when PCC was used as the binder. These findings suggest that WRAs can be suitably exploited for CPB of sulphide-rich tailings to improve the strength and stability in short and long terms allowing to reduce binder costs in a CPB plant. PMID:20382473

  5. In vivowide-field multispectral scanning laser ophthalmoscopy-optical coherence tomography mouse retinal imager: longitudinal imaging of ganglion cells, microglia, and Müller glia, and mapping of the mouse retinal and choroidal vasculature

    Science.gov (United States)

    Zhang, Pengfei; Zam, Azhar; Jian, Yifan; Wang, Xinlei; Li, Yuanpei; Lam, Kit S.; Burns, Marie E.; Sarunic, Marinko V.; Pugh, Edward N., Jr.; Zawadzki, Robert J.

    2015-12-01

    Scanning laser ophthalmoscopy (SLO) and optical coherence tomography (OCT) provide complementary views of the retina, with the former collecting fluorescence data with good lateral but relatively low-axial resolution, and the latter collecting label-free backscattering data with comparable lateral but much higher axial resolution. To take maximal advantage of the information of both modalities in mouse retinal imaging, we have constructed a compact, four-channel, wide-field (˜50 deg) system that simultaneously acquires and automatically coregisters three channels of confocal SLO and Fourier domain OCT data. The scanner control system allows "zoomed" imaging of a region of interest identified in a wide-field image, providing efficient digital sampling and localization of cellular resolution features in longitudinal imaging of individual mice. The SLO is equipped with a "flip-in" spectrometer that enables spectral "fingerprinting" of fluorochromes. Segmentation of retina layers and en face display facilitate spatial comparison of OCT data with SLO fluorescence patterns. We demonstrate that the system can be used to image an individual retinal ganglion cell over many months, to simultaneously image microglia and Müller glia expressing different fluorochromes, to characterize the distinctive spatial distributions and clearance times of circulating fluorochromes with different molecular sizes, and to produce unequivocal images of the heretofore uncharacterized mouse choroidal vasculature.

  6. Development and Deployment of a Compact Eye-Safe Scanning Differential absorption Lidar (DIAL) for Spatial Mapping of Carbon Dioxide for Monitoring/Verification/Accounting at Geologic Sequestration Sites

    Energy Technology Data Exchange (ETDEWEB)

    Repasky, Kevin

    2014-03-31

    A scanning differential absorption lidar (DIAL) instrument for monitoring carbon dioxide has been developed. The laser transmitter uses two tunable discrete mode laser diodes (DMLD) operating in the continuous wave (cw) mode with one locked to the online absorption wavelength and the other operating at the offline wavelength. Two in-line fiber optic switches are used to switch between online and offline operation. After the fiber optic switch, an acousto- optic modulator (AOM) is used to generate a pulse train used to injection seed an erbium doped fiber amplifier (EDFA) to produce eye-safe laser pulses with maximum pulse energies of 66 {micro}J, a pulse repetition frequency of 15 kHz, and an operating wavelength of 1.571 {micro}m. The DIAL receiver uses a 28 cm diameter Schmidt-Cassegrain telescope to collect that backscattered light, which is then monitored using a photo-multiplier tube (PMT) module operating in the photon counting mode. The DIAL instrument has been operated from a laboratory environment on the campus of Montana State University, at the Zero Emission Research Technology (ZERT) field site located in the agricultural research area on the western end of the Montana State University campus, and at the Big Sky Carbon Sequestration Partnership site located in north-central Montana. DIAL data has been collected and profiles have been validated using a co-located Licor LI-820 Gas Analyzer point sensor.

  7. The conical scan radiometer

    Science.gov (United States)

    Prosch, T.; Hennings, D.

    1982-07-01

    A satellite-borne conical scan radiometer (CSR) is proposed, offering multiangular and multispectral measurements of Earth radiation fields, including the total radiances, which are not available from conventional radiometers. Advantages of the CSR for meteorological studies are discussed. In comparison to conventional cross track scanning instruments, the CSR is unique with respect to the selected picture element size which is kept constant by means of a specially shaped detector matrix at all scan angles. The conical scan mode offers the chance to improve angular sampling. Angular sampling gaps of previous satellite-borne radiometers can be interpolated and complemented by CSR data. Radiances are measured through 10 radiometric channels which are selected to study cloudiness, water vapor, ozone, surface albedo, ground and mean stratospheric temperature, and aerosols.

  8. Pediatric CT Scans

    Science.gov (United States)

    The Radiation Epidemiology Branch and collaborators have initiated a retrospective cohort study to evaluate the relationship between radiation exposure from CT scans conducted during childhood and adolescence and the subsequent development of cancer.

  9. Pelvic CT scan

    Science.gov (United States)

    ... Abscess (collection of pus) Bladder stones Broken bone Cancer Diverticulitis ... scans over time may increase your risk of cancer. But the risk from any ... to contrast dye. Let your provider know if you have ever ...

  10. Sinus CT scan

    Science.gov (United States)

    ... may be due to: Birth defects Bone fractures Cancer Polyps in the sinuses Sinus infection (sinusitis) ... scans over time may increase your risk for cancer. However, the risk ... to contrast dye. Let your provider know if you have ever ...

  11. Scanning ultrafast electron microscopy

    OpenAIRE

    Yang, Ding-Shyue; Mohammed, Omar F.; Zewail, Ahmed H.

    2010-01-01

    Progress has been made in the development of four-dimensional ultrafast electron microscopy, which enables space-time imaging of structural dynamics in the condensed phase. In ultrafast electron microscopy, the electrons are accelerated, typically to 200 keV, and the microscope operates in the transmission mode. Here, we report the development of scanning ultrafast electron microscopy using a field-emission-source configuration. Scanning of pulses is made in the single-electron mode, for whic...

  12. Interactions between genetic admixture, ethnic identity, APOE genotype and dementia prevalence in an admixed Cuban sample; a cross-sectional population survey and nested case-control study

    Directory of Open Access Journals (Sweden)

    Hernandez Milagros

    2011-03-01

    Full Text Available Abstract Background The prevalence and incidence of dementia are low in Nigeria, but high among African-Americans. In these populations there is a high frequency of the risk-conferring APOE-e4 allele, but the risk ratio is less than in Europeans. In an admixed population of older Cubans we explored the effects of ethnic identity and genetic admixture on APOE genotype, its association with dementia, and dementia prevalence. Methods A cross-sectional catchment area survey of 2928 residents aged 65 and over, with a nested case-control study of individual admixture. Dementia diagnosis was established using 10/66 Dementia and DSM-IV criteria. APOE genotype was determined in 2520 participants, and genetic admixture in 235 dementia cases and 349 controls. Results Mean African admixture proportions were 5.8% for 'white', 28.6% for 'mixed' and 49.6% for 'black' ethnic identities. All three groups were substantially admixed with considerable overlap. African admixture was linearly related to number of APOE-e4 alleles. One or more APOE-e4 alleles was associated with dementia in 'white' and 'black' but not 'mixed' groups but neither this, nor the interaction between APOE-e4 and African admixture (PR 0.52, 95% CI 0.13-2.08 were statistically significant. Neither ethnic identity nor African admixture was associated with dementia prevalence when assessed separately. However, considering their joint effects African versus European admixture was independently associated with a higher prevalence, and 'mixed' or 'black' identity with a lower prevalence of dementia. Conclusions APOE genotype is strongly associated with ancestry. Larger studies are needed to confirm whether the concentration of the high-risk allele in those with African ancestry is offset by an attenuation of its effect. Counter to our hypothesis, African admixture may be associated with higher risk of dementia. Although strongly correlated, effects of admixture and ethnic identity should be

  13. Lung Ventilation/Perfusion Scan

    Science.gov (United States)

    ... two types of scans: ventilation and perfusion. The ventilation scan shows where air flows in your lungs. The perfusion scan shows where blood flows in your lungs. Both scans use radioisotopes (a low-risk radioactive substance). For the ventilation scan, you ...

  14. Scanning Probe Microscopy and Spectroscopy

    Science.gov (United States)

    Wiesendanger, Roland

    1994-09-01

    Preface; List of acronyms; Introduction; Part I. Experimental Methods and Theoretical Background of Scanning Probe Microscopy and Spectroscopy: 1. Scanning tunnelling microscopy; 2. Scanning force microscopy; 3. Related scanning probe techniques; Part II. Applications of Scanning Probe Microscopy and Spectroscopy: 4. Condensed matter physics; 5. Chemistry; 6. Organic materials; 7. Metrology and standards; 8. Nanotechnology; References; Index.

  15. Combination of admixtures to improve the robustness of high-volume fly ash concrete in hot weather[ACI SP-239

    Energy Technology Data Exchange (ETDEWEB)

    Nkinamubanzi, P.C. [Natural Resources Canada, Ottawa, ON (Canada). CANMET International Centre for Sustainable Development of Cement and Concrete]|[American Concrete Inst. Farmington Hills, MI (United States); Bhattacharya, A.; Sharma, A. [Hindustan Construction Co., Mumbai (India)

    2006-07-01

    A precise admixtures system is needed when using high-volume fly ash concrete as fresh concrete occasionally undergoes rapid slump loss after mixing, which can cause problems with casting, pumping and finishing of the concrete in hot weather. This paper provided details of a study conducted to implement high-volume fly ash concrete technology in India. Different families of admixtures were investigated to determine their water reduction capacities. A set-retarding admixture was used in some of the concrete mixtures in order to determine its efficacy. An Indian Portland cement was used to create a total of 22 different concrete mixtures. Four different fly ashes were used to replace portions of the concrete. The slump of the fresh concrete mixture was monitored for 2 to 3 hours. Unit weight and temperature of the concrete was measured. Specimens were cast in steel moulds in order to determine the compressive strength and unit weight of the hardened concrete. The concretes were demoulded after 24 hours and cured in a water tank. Results of the study showed that 4 concrete mixtures showed good slump retention after 2 hours. The concretes were made using a combination of polycarboxylate-based admixtures from the naphthalene family. Concrete mixtures using admixtures made from sulfonated polymers also showed good slump resistance. Results showed that the selection of good combinations of admixtures can lead to excellent high volume fly ash concrete mixtures that are resistant to hot weather conditions. Exceptional results were achieved with concrete mixtures using a combination of polycarboxylates-based superplasticizers and sulfonated mid-range water-reducing admixtures. 7 refs., 8 tabs., 3 figs.

  16. Coagulated silica - a-SiO2 admixture in cement paste

    Science.gov (United States)

    Pokorný, Jaroslav; Pavlíková, Milena; Záleská, Martina; Rovnaníková, Pavla; Pavlík, Zbyšek

    2016-07-01

    Amorphous silica (a-SiO2) in fine-grained form possesses a high pozzolanic activity which makes it a valuable component of blended binders in concrete production. The origin of a-SiO2 applied in cement-based composites is very diverse. SiO2 in amorphous form is present in various amounts in quite a few supplementary cementing materials (SCMs) being used as partial replacement of Portland cement. In this work, the applicability of a commercially produced coagulated silica powder as a partial replacement of Portland cement in cement paste mix design is investigated. Portland cement CEM I 42.5R produced according to the EU standard EN 197-1 is used as a reference binder. Coagulated silica is applied in dosages of 5 and 10 % by mass of cement. The water/binder ratio is kept constant in all the studied pastes. For the applied silica, specific surface area, density, loss on ignition, pozzolanic activity, chemical composition, and SiO2 amorphous phase content are determined. For the developed pastes on the basis of cement-silica blended binder, basic physical properties as bulk density, matrix density, and total open porosity are accessed. Pore size distribution is determined using MIP analysis. Initial and final setting times of fresh mixtures are measured by automatic Vicat apparatus. Effect of silica admixture on mechanical resistivity is evaluated using compressive strength, bending strength, and dynamic Young's modulus measurement. The obtained data gives evidence of a decreased workability of paste mixtures with silica, whereas the setting process is accelerated. On the other hand, reaction activity of silica with Portland cement minerals results in a slight decrease of porosity and improvement of mechanical resistivity of cement pastes containing a-SiO2.

  17. Straightforward inference of ancestry and admixture proportions through ancestry-informative insertion deletion multiplexing.

    Directory of Open Access Journals (Sweden)

    Rui Pereira

    Full Text Available Ancestry-informative markers (AIMs show high allele frequency divergence between different ancestral or geographically distant populations. These genetic markers are especially useful in inferring the likely ancestral origin of an individual or estimating the apportionment of ancestry components in admixed individuals or populations. The study of AIMs is of great interest in clinical genetics research, particularly to detect and correct for population substructure effects in case-control association studies, but also in population and forensic genetics studies. This work presents a set of 46 ancestry-informative insertion deletion polymorphisms selected to efficiently measure population admixture proportions of four different origins (African, European, East Asian and Native American. All markers are analyzed in short fragments (under 230 basepairs through a single PCR followed by capillary electrophoresis (CE allowing a very simple one tube PCR-to-CE approach. HGDP-CEPH diversity panel samples from the four groups, together with Oceanians, were genotyped to evaluate the efficiency of the assay in clustering populations from different continental origins and to establish reference databases. In addition, other populations from diverse geographic origins were tested using the HGDP-CEPH samples as reference data. The results revealed that the AIM-INDEL set developed is highly efficient at inferring the ancestry of individuals and provides good estimates of ancestry proportions at the population level. In conclusion, we have optimized the multiplexed genotyping of 46 AIM-INDELs in a simple and informative assay, enabling a more straightforward alternative to the commonly available AIM-SNP typing methods dependent on complex, multi-step protocols or implementation of large-scale genotyping technologies.

  18. Admixture in Humans of Two Divergent Plasmodium knowlesi Populations Associated with Different Macaque Host Species.

    Directory of Open Access Journals (Sweden)

    Paul C S Divis

    2015-05-01

    Full Text Available Human malaria parasite species were originally acquired from other primate hosts and subsequently became endemic, then spread throughout large parts of the world. A major zoonosis is now occurring with Plasmodium knowlesi from macaques in Southeast Asia, with a recent acceleration in numbers of reported cases particularly in Malaysia. To investigate the parasite population genetics, we developed sensitive and species-specific microsatellite genotyping protocols and applied these to analysis of samples from 10 sites covering a range of >1,600 km within which most cases have occurred. Genotypic analyses of 599 P. knowlesi infections (552 in humans and 47 in wild macaques at 10 highly polymorphic loci provide radical new insights on the emergence. Parasites from sympatric long-tailed macaques (Macaca fascicularis and pig-tailed macaques (M. nemestrina were very highly differentiated (FST = 0.22, and K-means clustering confirmed two host-associated subpopulations. Approximately two thirds of human P. knowlesi infections were of the long-tailed macaque type (Cluster 1, and one third were of the pig-tailed-macaque type (Cluster 2, with relative proportions varying across the different sites. Among the samples from humans, there was significant indication of genetic isolation by geographical distance overall and within Cluster 1 alone. Across the different sites, the level of multi-locus linkage disequilibrium correlated with the degree of local admixture of the two different clusters. The widespread occurrence of both types of P. knowlesi in humans enhances the potential for parasite adaptation in this zoonotic system.

  19. Effects of birthplace and individual genetic admixture on lung volume and exercise phenotypes of Peruvian Quechua.

    Science.gov (United States)

    Brutsaert, Tom D; Parra, Esteban; Shriver, Mark; Gamboa, Alfredo; Palacios, Jose-Antonio; Rivera, Maria; Rodriguez, Ivette; León-Velarde, Fabiola

    2004-04-01

    Forced vital capacity (FVC) and maximal exercise response were measured in two populations of Peruvian males (age, 18-35 years) at 4,338 m who differed by the environment in which they were born and raised, i.e., high altitude (Cerro de Pasco, Peru, BHA, n = 39) and sea level (Lima, Peru, BSL, n = 32). BSL subjects were transported from sea level to 4,338 m, and were evaluated within 24 hr of exposure to hypobaric hypoxia. Individual admixture level (ADMIX, % Spanish ancestry) was estimated for each subject, using 22 ancestry-informative genetic markers and also by skin reflectance measurement (MEL). Birthplace accounted for the approximately 10% larger FVC (P < 0.001), approximately 15% higher maximal oxygen consumption (VO(2)max, ml.min(-1).kg(-1)) (P < 0.001), and approximately 5% higher arterial oxygen saturation during exercise (SpO(2)) (P < 0.001) of BHA subjects. ADMIX was low in both study groups, averaging 9.5 +/- 2.6% and 2.1 +/- 0.3% in BSL and BHA subjects, respectively. Mean underarm MEL was significantly higher in the BSL group (P < 0.001), despite higher ADMIX. ADMIX was not associated with any study phenotype, but study power was not sufficient to evaluate hypotheses of genetic adaptation via the ADMIX variable. MEL and FVC were positively correlated in the BHA (P = 0.035) but not BSL (P = 0.335) subjects. However, MEL and ADMIX were not correlated across the entire study sample (P = 0.282). In summary, results from this study emphasize the importance of developmental adaptation to high altitude. While the MEL-FVC correlation may reflect genetic adaptation to high altitude, study results suggest that alternate (environmental) explanations be considered.

  20. Lung scans and malignancy

    International Nuclear Information System (INIS)

    An experience of pulmonary isotope scanning carried out with mercury 197 labelled mercury chloride and acetate, cobalt 57-labelled bleomycin, and Cu67 and Cu64 labelled copper citrate was presented. The scans were carried out with various isotopes supplied by the French Atomic Energy Authority, and gave comparable results, which may be summarised as follows: increased uptake in more than 90% of cases of carcinoma, absent uptake in all cases of benign tumour, frequent increased uptake in acute or advanced inflammatory lesions, absence of uptake, very commonly, in tuberculoma and chronic lesions with scar formation. Radio-isotope scan using Cu67 labelled copper citrate permitted discrimination of malignant tumours (increased fixation which showed up best at the 24th hour) from inflammatory lesions (increased fixation which was reduced on the 24th hour). The positive or negative character of the fixation in a given lesions remains the same, whatever the isotope used in our experience

  1. Adaptive Optical Scanning Holography

    Science.gov (United States)

    Tsang, P. W. M.; Poon, Ting-Chung; Liu, J.-P.

    2016-01-01

    Optical Scanning Holography (OSH) is a powerful technique that employs a single-pixel sensor and a row-by-row scanning mechanism to capture the hologram of a wide-view, three-dimensional object. However, the time required to acquire a hologram with OSH is rather lengthy. In this paper, we propose an enhanced framework, which is referred to as Adaptive OSH (AOSH), to shorten the holographic recording process. We have demonstrated that the AOSH method is capable of decreasing the acquisition time by up to an order of magnitude, while preserving the content of the hologram favorably. PMID:26916866

  2. Influence of Air Temperature on the Performance of Different Water-Reducing Admixtures with Respect to the Properties of Fresh and Hardened Mortar

    Directory of Open Access Journals (Sweden)

    Wilson Ricardo Leal Silva

    2010-01-01

    Full Text Available The performance of water-reducing admixtures used in concrete is affected by the weather conditions to which the concrete mixture is exposed. The most used WRAs are lignosulfonate, naphthalene, and polycarboxylate. However, they react differently to weather conditions, especially to air temperature. Therefore, it can be useful to evaluate how temperature affects admixture performance. In this study, the performance of three admixtures (naphthalene, lignosulfonate, and polycarboxylate was evaluated at 15, 25, and 35°C by means of the flow table test, mixture air content, and compressive strength. Moreover, mixture temperature was monitored and time-temperature curves were plotted in order to assess whether the admixtures affected cement hydration reactions at different temperatures. The final results indicate that an increase in temperature leads to an increase in saturation dosage; lignosulfonate had the most pronounced retarding effect, followed by polycarboxylate, and finally, naphthalene, and considering the weather conditions in the area where the study was carried, the final finding would be that the naphthalene-based admixture had the best performance.

  3. Fine Sand Stabilization Using Sanitary Ware Waste as Admixture for Design of Flexible Pavement in Construction of Roads

    Directory of Open Access Journals (Sweden)

    Akash Gupta

    2016-08-01

    Full Text Available When designing and constructing highways or more generally any road on fine sands type of soil, it is essential to make sure that the foundation soil is providing a stable, non-yielding surface for the movement of heavy vehicles. Fine sand is found in abundance in Western Rajasthan (India in which hundreds of kilometers of new roads and highways are being constructed and maintained every year. As per Indian Standard Classification System of soils, the fine sand has nil cohesion. Due to very low compressive strength and high permeability, fine sand is not readily suitable for supporting flexible pavements as sub grade. This study discusses the possibility of stabilization of fine sand using Sanitary Ware Waste as admixture. Present work has been taken up by addition of 4.75 mm sieve passed and 2.36 mm sieve retained Sanitary Ware Waste as admixture. The varying percentage 0%, 2%, 4%, 8% and 12% of sanitary ware waste were mixed with fine sand of different densities 1.50 gm/cc, 1.55 gm/cc and 1.58 gm/cc (M.D.D.. All the California Bearing Ratio Tests were conducted at different mix compositions of sanitary ware waste and fine sand of different dry densities as arrived from Standard Proctor Test. Falling-Head Permeability Tests were also performed on different mix compositions. On the basis of the experiments performed, it is determined that the stabilization of fine sand using sanitary ware waste as admixture improves the strength characteristics of the fine sand so that it becomes usable as a base material for flexible pavement in construction of roads.

  4. Sociocultural behavior, sex-biased admixture, and effective population sizes in Central African Pygmies and non-Pygmies.

    Science.gov (United States)

    Verdu, Paul; Becker, Noémie S A; Froment, Alain; Georges, Myriam; Grugni, Viola; Quintana-Murci, Lluis; Hombert, Jean-Marie; Van der Veen, Lolke; Le Bomin, Sylvie; Bahuchet, Serge; Heyer, Evelyne; Austerlitz, Frédéric

    2013-04-01

    Sociocultural phenomena, such as exogamy or phylopatry, can largely determine human sex-specific demography. In Central Africa, diverging patterns of sex-specific genetic variation have been observed between mobile hunter-gatherer Pygmies and sedentary agricultural non-Pygmies. However, their sex-specific demography remains largely unknown. Using population genetics and approximate Bayesian computation approaches, we inferred male and female effective population sizes, sex-specific migration, and admixture rates in 23 Central African Pygmy and non-Pygmy populations, genotyped for autosomal, X-linked, Y-linked, and mitochondrial markers. We found much larger effective population sizes and migration rates among non-Pygmy populations than among Pygmies, in agreement with the recent expansions and migrations of non-Pygmies and, conversely, the isolation and stationary demography of Pygmy groups. We found larger effective sizes and migration rates for males than for females for Pygmies, and vice versa for non-Pygmies. Thus, although most Pygmy populations have patrilocal customs, their sex-specific genetic patterns resemble those of matrilocal populations. In fact, our results are consistent with a lower prevalence of polygyny and patrilocality in Pygmies compared with non-Pygmies and a potential female transmission of reproductive success in Pygmies. Finally, Pygmy populations showed variable admixture levels with the non-Pygmies, with often much larger introgression from male than from female lineages. Social discrimination against Pygmies triggering complex movements of spouses in intermarriages can explain these male-biased admixture patterns in a patrilocal context. We show how gender-related sociocultural phenomena can determine highly variable sex-specific demography among populations, and how population genetic approaches contrasting chromosomal types allow inferring detailed human sex-specific demographic history.

  5. Influence of shrinkage-reducing admixture on drying shrinkage and mechanical properties of high-performance concrete

    Institute of Scientific and Technical Information of China (English)

    Nguyen Quangphu; Jiang Linhua; Liu Jiaping; Tian Qian; Do Tienquan

    2008-01-01

    High-performance concrete (HPC) has specific performance advantages over conventional concrete in strength and durability. HPC mixtures are usually produced with water/binder mass ratios (mw/mB) in the range of 0.2-0.4, so volume changes of concrete as a result of drying, chemical reactions, and temperature change cannot be avoided. For these reasons, shrinkage and cracking are frequent phenomena. It is necessary to add some types of admixture for reduction of shrinkage and cracking of HPC. This study used a shrinkage-reducing admixture (SRA) for that purpose. Concrete was prepared with two different mw/mB(0.22 and 0.40) and four different mass fractions of SRA to binder (w(SRA) = 0%, 1%, 2%, and 4%). The mineral admixtures used for concrete mixes were: 25% fly ash (FA) and 25% slag by mass of binder for the mixture with mw/mB=0.40, and 15% silica fume (SF) and 25% FA for the mixture with mw/ma=0.22. Tests were conducted on 24 prismatic specimens, and shrinkage strains were measured through 120 days of drying. Compressive strength, splitting strength, and static modulus of elasticity were also determined. The results show that the SRA effectively reduces some mechanical properties of HPC. The reductions in compressive strength, splitting tensile strength, and elastic modulus of the concrete were 7%-24%, 9%-19%, and 5%-12%, respectively, after 90 days, compared to concrete mixtures without SRA. SRA can also help reduce drying shrinkage of concrete. The shrinkage strains of HPC with SRA were only as high as 41% of the average free shrinkage of concrete without SRA after 120 days of drying.

  6. Historical environmental change in Africa drives divergence and admixture of Aedes aegypti mosquitoes: a precursor to successful worldwide colonization?

    Science.gov (United States)

    Bennett, Kelly Louise; Shija, Fortunate; Linton, Yvonne-Marie; Misinzo, Gerald; Kaddumukasa, Martha; Djouaka, Rousseau; Anyaele, Okorie; Harris, Angela; Irish, Seth; Hlaing, Thaung; Prakash, Anil; Lutwama, Julius; Walton, Catherine

    2016-09-01

    Increasing globalization has promoted the spread of exotic species, including disease vectors. Understanding the evolutionary processes involved in such colonizations is both of intrinsic biological interest and important to predict and mitigate future disease risks. The Aedes aegypti mosquito is a major vector of dengue, chikungunya and Zika, the worldwide spread of which has been facilitated by Ae. aegypti's adaption to human-modified environments. Understanding the evolutionary processes involved in this invasion requires characterization of the genetic make-up of the source population(s). The application of approximate Bayesian computation (ABC) to sequence data from four nuclear and one mitochondrial marker revealed that African populations of Ae. aegypti best fit a demographic model of lineage diversification, historical admixture and recent population structuring. As ancestral Ae. aegypti were dependent on forests, this population history is consistent with the effects of forest fragmentation and expansion driven by Pleistocene climatic change. Alternatively, or additionally, historical human movement across the continent may have facilitated their recent spread and mixing. ABC analysis and haplotype networks support earlier inferences of a single out-of-Africa colonization event, while a cline of decreasing genetic diversity indicates that Ae. aegypti moved first from Africa to the Americas and then to Asia. ABC analysis was unable to verify this colonization route, possibly because the genetic signal of admixture obscures the true colonization pathway. By increasing genetic diversity and forming novel allelic combinations, divergence and historical admixture within Africa could have provided the adaptive potential needed for the successful worldwide spread of Ae. aegypti. PMID:27439067

  7. Bone scan in rheumatology

    International Nuclear Information System (INIS)

    In this chapter a revision is made concerning different uses of bone scan in rheumatic diseases. These include reflex sympathetic dystrophy, osteomyelitis, spondyloarthropaties, metabolic bone diseases, avascular bone necrosis and bone injuries due to sports. There is as well some comments concerning pediatric pathology and orthopedics. (authors). 19 refs., 9 figs

  8. Scan This Book!

    Science.gov (United States)

    Albanese, Andrew Richard

    2007-01-01

    In this article, the author presents an interview with Brewster Kahle, leader of the Open Content Alliance (OCA). OCA book scan program is an alternative to Google's library project that aims to make books accessible online. In this interview, Kahle discusses his views on the challenges of getting books on the Web, on Google's library…

  9. Lung gallium scan

    Science.gov (United States)

    ... Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team. Related MedlinePlus Health Topics Lung Diseases Nuclear Scans Sarcoidosis Browse the Encyclopedia A.D.A. ...

  10. Surface micromachined scanning mirrors

    DEFF Research Database (Denmark)

    Mattsson, Kent Erik

    1992-01-01

    Both aluminum cantilever and torsional scanning mirrors have been fabricated and their static and dynamic properties are studied experimentally and theoretically. The experiments showed resonance frequencies in the range of 163 k-Hz - 632 kHz for cantilever beams with Q values between 5 and 11. T...

  11. Scanning bubble chamber pictures

    CERN Multimedia

    1974-01-01

    These were taken at the 2 m hydrogen bubble chamber. The photo shows an early Shiva system where the pre-measurements needed to qualify the event were done manually (cf photo 7408136X). The scanning tables were located in bld. 12. Gilberte Saulmier sits on foreground, Inge Arents at centre.

  12. Low-frequency resonances of the refractive index in weakly ionized plasma with an admixture of dust

    International Nuclear Information System (INIS)

    The propagation of low-frequency electromagnetic waves along the magnetic field in weakly ionized plasma with an admixture of dust is studied in the framework of the Hall magnetohydrodynamics. Explicit expressions for the coefficients of magnetic field diffusion in plasma are derived. The resonance of the refractive index is found to occur for either right- or left-hand polarized waves. A quantitative criterion is obtained that allows one to determine the polarization of waves that experience resonance at given plasma parameters. The physical mechanism of the resonance is discussed, and the obtained results are compared with the available literature data

  13. Map Projection

    CERN Document Server

    Ghaderpour, Ebrahim

    2014-01-01

    In this paper, we introduce some known map projections from a model of the Earth to a flat sheet of paper or map and derive the plotting equations for these projections. The first fundamental form and the Gaussian fundamental quantities are defined and applied to obtain the plotting equations and distortions in length, shape and size for some of these map projections.

  14. Harmonic Maps and Biharmonic Maps

    OpenAIRE

    Hajime Urakawa

    2015-01-01

    This is a survey on harmonic maps and biharmonic maps into (1) Riemannian manifolds of non-positive curvature, (2) compact Lie groups or (3) compact symmetric spaces, based mainly on my recent works on these topics.

  15. Current situation and reflection of domestic intravenous pharmacy admixture models%国内静脉药物调配模式现状与思考

    Institute of Scientific and Technical Information of China (English)

    夏英华; 毛燕君; 朱建英

    2012-01-01

    This article summarized the current situation of three intravenous pharmacy admixture models,including ward intravenous drag distribution model, Pharmacy Intravenous Admixture Services (PIVAS) and decentralized distribution model. It analyzed the advantages and disadvantages,and on the basis,reflection and suggestions of pharmacy admixture methods were put forward.%文章分别归纳了国内病区药物自配模式、静脉药物集中调配模式和分散药物调配模式的发展现状及其优缺点,在此基础上,对国内静脉药物调配模式的发展进行思考并提出建议.

  16. Energy Scan program

    Directory of Open Access Journals (Sweden)

    Poniatowska Katarzyna M.

    2014-04-01

    Full Text Available Femtoscopy of two non-identical particles in heavy ion collisions enables one to study the space-time asymmetry in the particle's emission process. Theoretical studies based on EPOS model performed for collision energies from the Beam Energy Scan program in STAR allow us to investigate the dependence of source sizes and dynamics effects. Obtained information will enable us to predict the collective behaviour of femtoscopic particle's source.

  17. Forensic Scanning Electron Microscope

    Science.gov (United States)

    Keeley, R. H.

    1983-03-01

    The scanning electron microscope equipped with an x-ray spectrometer is a versatile instrument which has many uses in the investigation of crime and preparation of scientific evidence for the courts. Major applications include microscopy and analysis of very small fragments of paint, glass and other materials which may link an individual with a scene of crime, identification of firearms residues and examination of questioned documents. Although simultaneous observation and chemical analysis of the sample is the most important feature of the instrument, other modes of operation such as cathodoluminescence spectrometry, backscattered electron imaging and direct x-ray excitation are also exploited. Marks on two bullets or cartridge cases can be compared directly by sequential scanning with a single beam or electronic linkage of two instruments. Particles of primer residue deposited on the skin and clothing when a gun is fired can be collected on adhesive tape and identified by their morphology and elemental composition. It is also possible to differentiate between the primer residues of different types of ammunition. Bullets may be identified from the small fragments left behind as they pass through the body tissues. In the examination of questioned documents the scanning electron microscope is used to establish the order in which two intersecting ink lines were written and to detect traces of chemical markers added to the security inks on official documents.

  18. Admixture in Latin America: geographic structure, phenotypic diversity and self-perception of ancestry based on 7,342 individuals.

    Directory of Open Access Journals (Sweden)

    Andrés Ruiz-Linares

    2014-09-01

    Full Text Available The current genetic makeup of Latin America has been shaped by a history of extensive admixture between Africans, Europeans and Native Americans, a process taking place within the context of extensive geographic and social stratification. We estimated individual ancestry proportions in a sample of 7,342 subjects ascertained in five countries (Brazil, Chile, Colombia, México and Perú. These individuals were also characterized for a range of physical appearance traits and for self-perception of ancestry. The geographic distribution of admixture proportions in this sample reveals extensive population structure, illustrating the continuing impact of demographic history on the genetic diversity of Latin America. Significant ancestry effects were detected for most phenotypes studied. However, ancestry generally explains only a modest proportion of total phenotypic variation. Genetically estimated and self-perceived ancestry correlate significantly, but certain physical attributes have a strong impact on self-perception and bias self-perception of ancestry relative to genetically estimated ancestry.

  19. Range expansion of house sparrows (Passer domesticus) in Kenya: evidence of genetic admixture and human-mediated dispersal.

    Science.gov (United States)

    Schrey, Aaron W; Liebl, Andrea L; Richards, Christina L; Martin, Lynn B

    2014-01-01

    Introduced species offer an opportunity to study the ecological process of range expansions. Recently, 3 mechanisms have been identified that may resolve the genetic paradox (the seemingly unlikely success of introduced species given the expected reduction in genetic diversity through bottlenecks or founder effects): multiple introductions, high propagule pressure, and epigenetics. These mechanisms are probably also important in range expansions (either natural or anthropogenic), yet this possibility remains untested in vertebrates. We used microsatellite variation (7 loci) in house sparrows (Passer domesticus), an introduced species that has been spreading across Kenya for ~60 years, to determine if patterns of variation could explain how this human commensal overcame the genetic paradox and expresses such considerable phenotypic differentiation across this new range. We note that in some cases, polygenic traits and epistasis among genes, for example, may not have negative effects on populations. House sparrows arrived in Kenya by a single introduction event (to Mombasa, ~1950) and have lower genetic diversity than native European and introduced North American populations. We used Bayesian clustering of individuals (n = 233) to detect that at least 2 types of range expansion occurred in Kenya: one with genetic admixture and one with little to no admixture. We also found that genetic diversity increased toward a range edge, and the range expansion was consistent with long-distance dispersal. Based on these data, we expect that the Kenyan range expansion was anthropogenically influenced, as the expansions of other introduced human commensals may also be.

  20. Admixture in Latin America: Geographic Structure, Phenotypic Diversity and Self-Perception of Ancestry Based on 7,342 Individuals

    Science.gov (United States)

    Ruiz-Linares, Andrés; Adhikari, Kaustubh; Acuña-Alonzo, Victor; Quinto-Sanchez, Mirsha; Jaramillo, Claudia; Arias, William; Fuentes, Macarena; Pizarro, María; Everardo, Paola; de Avila, Francisco; Gómez-Valdés, Jorge; León-Mimila, Paola; Hunemeier, Tábita; Ramallo, Virginia; Silva de Cerqueira, Caio C.; Burley, Mari-Wyn; Konca, Esra; de Oliveira, Marcelo Zagonel; Veronez, Mauricio Roberto; Rubio-Codina, Marta; Attanasio, Orazio; Gibbon, Sahra; Ray, Nicolas; Gallo, Carla; Poletti, Giovanni; Rosique, Javier; Schuler-Faccini, Lavinia; Salzano, Francisco M.; Bortolini, Maria-Cátira; Canizales-Quinteros, Samuel; Rothhammer, Francisco; Bedoya, Gabriel; Balding, David; Gonzalez-José, Rolando

    2014-01-01

    The current genetic makeup of Latin America has been shaped by a history of extensive admixture between Africans, Europeans and Native Americans, a process taking place within the context of extensive geographic and social stratification. We estimated individual ancestry proportions in a sample of 7,342 subjects ascertained in five countries (Brazil, Chile, Colombia, México and Perú). These individuals were also characterized for a range of physical appearance traits and for self-perception of ancestry. The geographic distribution of admixture proportions in this sample reveals extensive population structure, illustrating the continuing impact of demographic history on the genetic diversity of Latin America. Significant ancestry effects were detected for most phenotypes studied. However, ancestry generally explains only a modest proportion of total phenotypic variation. Genetically estimated and self-perceived ancestry correlate significantly, but certain physical attributes have a strong impact on self-perception and bias self-perception of ancestry relative to genetically estimated ancestry. PMID:25254375

  1. Secondary contact between Lycaeides idas and L. melissa in the Rocky Mountains: extensive admixture and a patchy hybrid zone.

    Science.gov (United States)

    Gompert, Zachariah; Lucas, Lauren K; Fordyce, James A; Forister, Matthew L; Nice, Chris C

    2010-08-01

    Studies of hybridization have increased our understanding of the nature of species boundaries, the process of speciation, and the effects of hybridization on the evolution of populations and species. In the present study we use genetic and morphological data to determine the outcome and consequences of secondary contact and hybridization between the butterfly species Lycaeides idas and L. melissa in the Rocky Mountains. Admixture proportions estimated from structure and geographical cline analysis indicate L. idas and L. melissa have hybridized extensively in the Rocky Mountains and that reproductive isolation was insufficient to prevent introgression for much of the genome. Geographical patterns of admixture suggest that hybridization between L. idas and L. melissa has led to the formation of a hybrid zone. The hybrid zone is relatively wide, given estimates of dispersal for Lycaeides butterflies, and does not show strong evidence of cline concordance among characters. We believe the structure of the Lycaeides hybrid zone might be best explained by the patchy distribution of Lycaeides, local extinction and colonization of habitat patches, environmental variation and weak overall selection against hybrids. We found no evidence that hybridization in the Rocky Mountains has resulted in the formation of independent hybrid species, in contrast to the outcome of hybridization between L. idas and L. melissa in the Sierra Nevada. Finally, our results suggest that differences in male morphology between L. idas and L. melissa might contribute to isolation, or perhaps even that selection has favoured the spread of L. melissa male genitalia alleles. PMID:20618903

  2. Gene admixture in ethnic populations in upper part of Silk Road revealed by mtDNA polymorphism

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To evaluate the gene admixture on the current genetic landscape in Gansu Corridor (GC) in China, the upper part of the ancient Silk Road which connects the Eastern and Central Asia, we examined mitochondrial DNA (mtDNA) polymorphisms of five ethnic populations in this study. Using PCR-RFLP and sequencing, we analyzed mtDNA haplotypes in 242 unrelated samples in three ethnic populations from the GC region and two ethnic populations from the adjacent Xinjiang Uygur Autonomous Region of China. We analyzed the data in comparison with the previously reported data from Eastern, Central and Western Asia and Europe. We found that both European-specific haplogroups and Eastern Asian-specific haplogroups exist in the Gansu Corridor populations, while a modest matrilineal gene flow from Europeans to this region was revealed. The Gansu Corridor populations are genetically located between Eastern Asians and Central Asians, both of who contributed significantly to the maternal lineages of the GC populations. This study made the landscape of the gene flow and admixture along the Silk Road from Europe, through Central Asia, to the upper part of the Silk Road more complete.

  3. Genetic dating indicates that the Asian–Papuan admixture through Eastern Indonesia corresponds to the Austronesian expansion

    Science.gov (United States)

    Xu, Shuhua; Pugach, Irina; Stoneking, Mark; Kayser, Manfred; Jin, Li

    2012-01-01

    Although the Austronesian expansion had a major impact on the languages of Island Southeast Asia, controversy still exists over the genetic impact of this expansion. The coexistence of both Asian and Papuan genetic ancestry in Eastern Indonesia provides a unique opportunity to address this issue. Here, we estimate recombination breakpoints in admixed genomes based on genome-wide SNP data and date the genetic admixture between populations of Asian vs. Papuan ancestry in Eastern Indonesia. Analyses of two genome-wide datasets indicate an eastward progression of the Asian admixture signal in Eastern Indonesia beginning about 4,000–3,000 y ago, which is in excellent agreement with inferences based on Austronesian languages. The average rate of spread of Asian genes in Eastern Indonesia was about 0.9 km/y. Our results indicate that the Austronesian expansion had a strong genetic as well as linguistic impact on Island Southeast Asia, and they significantly advance our understanding of the biological origins of human populations in the Asia–Pacific region. PMID:22396590

  4. Genetic dating indicates that the Asian-Papuan admixture through Eastern Indonesia corresponds to the Austronesian expansion.

    Science.gov (United States)

    Xu, Shuhua; Pugach, Irina; Stoneking, Mark; Kayser, Manfred; Jin, Li

    2012-03-20

    Although the Austronesian expansion had a major impact on the languages of Island Southeast Asia, controversy still exists over the genetic impact of this expansion. The coexistence of both Asian and Papuan genetic ancestry in Eastern Indonesia provides a unique opportunity to address this issue. Here, we estimate recombination breakpoints in admixed genomes based on genome-wide SNP data and date the genetic admixture between populations of Asian vs. Papuan ancestry in Eastern Indonesia. Analyses of two genome-wide datasets indicate an eastward progression of the Asian admixture signal in Eastern Indonesia beginning about 4,000-3,000 y ago, which is in excellent agreement with inferences based on Austronesian languages. The average rate of spread of Asian genes in Eastern Indonesia was about 0.9 km/y. Our results indicate that the Austronesian expansion had a strong genetic as well as linguistic impact on Island Southeast Asia, and they significantly advance our understanding of the biological origins of human populations in the Asia-Pacific region. PMID:22396590

  5. Effects of (V + A)-, S-, T-interaction admixtures and of a time reversal invariance violation on the first-forbidden beta-decay of RaE

    International Nuclear Information System (INIS)

    The shape factor and the electron longitudinal polarization of RaE have been calculated under the assumption of (V + A)-, S-, T-interaction admixtures. In addition the influence of a time reversal invariance violation has been considered. It is shown that the effect of (V + A) admixtures on the electron longitudinal polarization is enhanced by two orders of magnitude compared to the case of allowed transitions. Such an effect is also observed for the shape factor. It is also demonstrated that a time reversal invariance violation also affects the observables mentioned above. (orig.)

  6. Scanning measurement of Seebeck coefficient of a heated sample

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, G. Jeffrey; Iwanaga, Shiho

    2016-04-19

    A novel scanning Seebeck coefficient measurement technique is disclosed utilizing a cold scanning thermocouple probe tip on heated bulk and thin film samples. The system measures variations in the Seebeck coefficient within the samples. The apparatus may be used for two dimensional mapping of the Seebeck coefficient on the bulk and thin film samples. This technique can be utilized for detection of defective regions, as well as phase separations in the sub-mm range of various thermoelectric materials.

  7. Novel approach to stationary transmission scanning using Compton scattered radiation

    International Nuclear Information System (INIS)

    Transmission scanning-based estimation of the attenuation map plays a crucial role in quantitative radionuclide imaging. X-ray computed tomography (CT) reconstructs directly the attenuation coefficients map from data transmitted through the object. This paper proposes an alternative route for reconstructing the object attenuation map by exploiting Compton scatter of transmitted radiation from an externally placed radionuclide source. In contrast to conventional procedures, data acquisition is realized as a series of images parameterized by the Compton scattering angle and registered on a stationary gamma camera operating without spatial displacement. Numerical simulation results using realistic voxel-based phantoms are presented to illustrate the efficiency of this new transmission scanning approach for attenuation map reconstruction. The encouraging results presented in this paper may suggest the possibility of proposing a new concept for emission/transmission imaging using scattered radiation, which has many advantages compared to conventional technologies

  8. Visualization in Scanning

    International Nuclear Information System (INIS)

    Scanning is essentially a method of making the unknown known, and for the vast majority of scanning work this means making the invisible visible. Visualization is developed as a process involving a model of eye and brain function, display performance and counter performance combined with the spatial frequency components in the object scanned. The performance of a scanner or gamma camera depends in part on its display system and experiments have been performed to determine the fractional change in count-rate which can be perceived by the eye from colour, photoscan and cathode-ray tube displays, for both circular and line sources of radioactivity. For circular sources, colour and photoscan displays are capable of making 10% increases in count-rate perceptible in backgrounds ranging from 5 to 100 counts/s for sources of 1 to 4 cm diameter, whilst cathode-ray tube and black-mark displays show only 20% at best. The results for line sources are also given. In testing for the statistical significance of count-rate differences on a scan, the counts are usually compared for equal areas. On this basis the cathode-ray tube display is only able to show five standard deviations of difference whereas colour and photoscan displays show from 2.5 to 3 standard deviations, levels not usually accepted statistically as significant. It is suggested that if the eye examines the areas surrounding the area of interest then the significance of a count-rate difference may be established more accurately and in general will be increased, thereby accounting for the visualization of apparently 'insignificant' regions. This theory is used to predict the areas of count density which should be visually perceived in the presence of noise, and extended to consider practical display conditions, which have been described in this paper. The performance of a scanner can be considered in terms of its modulation transfer function (derived from a line spread function). Fourier analysis has been performed

  9. Multiplatform Mobile Laser Scanning: Usability and Performance

    Directory of Open Access Journals (Sweden)

    Yuwei Chen

    2012-08-01

    Full Text Available Mobile laser scanning is an emerging technology capable of capturing three-dimensional data from surrounding objects. With state-of-the-art sensors, the achieved point clouds capture object details with good accuracy and precision. Many of the applications involve civil engineering in urban areas, as well as traffic and other urban planning, all of which serve to make 3D city modeling probably the fastest growing market segment in this field. This article outlines multiplatform mobile laser scanning solutions such as vehicle- and trolley-operated urban area data acquisition, and boat-mounted equipment for fluvial environments. Moreover, we introduce a novel backpack version of mobile laser scanning equipment for surveying applications in the field of natural sciences where the requirements include precision and mobility in variable terrain conditions. In addition to presenting a technical description of the systems, we discuss the performance of the solutions in the light of various applications in the fields of urban mapping and modeling, fluvial geomorphology, snow-cover characterization, precision agriculture, and in monitoring the effects of climate change on permafrost landforms. The data performance of the mobile laser scanning approach is described by the results of an evaluation of the ROAMER on a permanent MLS test field. Furthermore, an in situ accuracy assessment using a field of spherical 3D targets for the newly-introduced Akhka backpack system is conducted and reported on.

  10. The KFUPM scanning nuclear microprobe facility

    International Nuclear Information System (INIS)

    The scanning nuclear microprobe facility recently installed on the tandetron accelerator of King Fahd University of Petroleum and Minerals in Dhahran, Saudi Arabia is described. The design is based on the Oxford magnetic quadrupole triplet lens system and can focus a beam of 2.5 MeV protons to a spot of about 1 μm diameter with a current of about 100 pA. Maximum scanning area is at present limited to 130 μm by 100 μm. Acceptance tests performed during the commissioning of the facility are discussed. Elemental maps of a catalyst by PIXE measurements are given to demonstrate the performance of the system. (orig.)

  11. The Scanning TMR Microscope for Biosensor Applications

    Directory of Open Access Journals (Sweden)

    Kunal N. Vyas

    2015-04-01

    Full Text Available We present a novel tunnel magnetoresistance (TMR scanning microscopeset-up capable of quantitatively imaging the magnetic stray field patterns of micron-sizedelements in 3D. By incorporating an Anderson loop measurement circuit for impedancematching, we are able to detect magnetoresistance changes of as little as 0.006%/Oe. By 3Drastering a mounted TMR sensor over our magnetic barcodes, we are able to characterisethe complex domain structures by displaying the real component, the amplitude and thephase of the sensor’s impedance. The modular design, incorporating a TMR sensor withan optical microscope, renders this set-up a versatile platform for studying and imagingimmobilised magnetic carriers and barcodes currently employed in biosensor platforms,magnetotactic bacteria and other complex magnetic domain structures of micron-sizedentities. The quantitative nature of the instrument and its ability to produce vector maps ofmagnetic stray fields has the potential to provide significant advantages over other commonlyused scanning magnetometry techniques.

  12. Consistent long-range linkage disequilibrium generated by admixture in a Bantu-Semitic hybrid population

    OpenAIRE

    Wilson, J F; Goldstein, D. B.

    2000-01-01

    Both the optimal marker density for genome scans in case-control association studies and the appropriate study design for the testing of candidate genes depend on the genomic pattern of linkage disequilibrium (LD). In this study, we provide the first conclusive demonstration that the diverse demographic histories of human populations have produced dramatic differences in genomewide patterns of LD. Using a panel of 66 markers spanning the X chromosome, we show that, in the Lemba, a Bantu-Semit...

  13. Kohonen's feature maps for fly ash categorization.

    Science.gov (United States)

    Nataraja, M C; Jayaram, M A; Ravikumar, C N

    2006-12-01

    Fly ash is a common admixture used in concrete and may constitute up to 50% by weight of the total binder material. Incorporation of fly ash in Portland-cement concrete is highly desirable due to technological, economic, and environmental benefits. This article demonstrates the use of artificial intelligence neural networks for the classification of fly ashes in to different groups. Kohonen's Self Organizing Feature Maps is used for the purpose. As chemical composition of fly ash is crucial in the performance of concrete, eight chemical attributes of fly ashes have been considered. The application of simple Kohonen's one-dimensional feature maps permitted to differentiate three main groups of fly ashes. Three one-dimensional feature maps of topology 8-16, 8-24 and 8-32 were explored. The overall classification result of 8-16 topology was found to be significant and encouraging. The data pertaining to 80 fly ash samples were collected from standard published works. The categorization was found to be excellent and compares well with Canadian Standard Association's [CSA A 3000] classification scheme. PMID:17285691

  14. Nuclear Medicine Scans for Cancer

    Science.gov (United States)

    ... My ACS » Your Local Offices Close + - Text Size Nuclear Medicine Scans for Cancer Other names for these ... inflammation, or cancer. Use of monoclonal antibodies in nuclear scans A special type of antibody made in ...

  15. First results from the INTEGRAL galactic plane scans

    DEFF Research Database (Denmark)

    Winkler, C.; Gehrels, N.; Schonfelder, V.;

    2003-01-01

    Scans of the Galactic plane performed at regular intervals constitute a key element of the guaranteed time observations of the INTEGRAL observing programme. These scans are done for two reasons: frequent monitoring of the Galactic plane in order to detect transient sources, and time resolved mapp...... mapping of the Galactic plane in continuum and diffuse line emission. This paper describes first results obtained from the Galactic plane scans executed so far during the early phase (Dec. 2002-May 2003) of the nominal mission.......Scans of the Galactic plane performed at regular intervals constitute a key element of the guaranteed time observations of the INTEGRAL observing programme. These scans are done for two reasons: frequent monitoring of the Galactic plane in order to detect transient sources, and time resolved...

  16. Scanned-cantilever atomic force microscope with large scanning range

    Institute of Scientific and Technical Information of China (English)

    Jintao Yang; Wendong Xu

    2006-01-01

    A scanned-cantilever atomic force microscope (AFM) with large scanning range is proposed, which adopts a new design named laser spot tracking. The scanned-cantilever AFM uses the separate flexure x-y scanner and z scanner instead of the conventional piezoelectric tube scanner. The closed-loop control and integrated capacitive sensors of these scanners can insure that the images of samples have excellent linearity and stability. According to the experimental results, the scanned-cantilever AFM can realize maximal 100 × 100 (μm) scanning range, and 1-nm resolution in z direction, which can meet the requirements of large scale sample testing.

  17. Causal mapping

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard

    2006-01-01

    The lecture note explains how to use the causal mapping method as well as the theoretical framework aoosciated to the method......The lecture note explains how to use the causal mapping method as well as the theoretical framework aoosciated to the method...

  18. Alkali-silica reactions of mortars produced by using waste glass as fine aggregate and admixtures such as fly ash and Li2CO3.

    Science.gov (United States)

    Topçu, Ilker Bekir; Boğa, Ahmet Raif; Bilir, Turhan

    2008-01-01

    Use of waste glass or glass cullet (GC) as concrete aggregate is becoming more widespread each day because of the increase in resource efficiency. Recycling of wastes is very important for sustainable development. When glass is used as aggregate in concrete or mortar, expansions and internal stresses occur due to an alkali-silica reaction (ASR). Furthermore, rapid loss in durability is generally observed due to extreme crack formation and an increase in permeability. It is necessary to use some kind of chemical or mineral admixture to reduce crack formation. In this study, mortar bars are produced by using three different colors of glass in four different quantities as fine aggregate by weight, and the effects of these glass aggregates on ASR are investigated, corresponding to ASTM C 1260. Additionally, in order to reduce the expansions of mortars, 10% and 20% fly ash (FA) as mineral admixture and 1% and 2% Li(2)CO(3) as chemical admixture are incorporated by weight in the cement and their effects on expansion are examined. It is observed that among white (WG), green (GG) and brown glass (BG) aggregates, WG aggregate causes the greatest expansion. In addition, expansion increases with an increase in amount of glass. According to the test results, it is seen that over 20% FA and 2% Li(2)CO(3) replacements are required to produce mortars which have expansion values below the 0.2% critical value when exposed to ASR. However, usages of these admixtures reduce expansions occurring because of ASR.

  19. Demonstration of scan path optimization in proton therapy

    International Nuclear Information System (INIS)

    A three-dimensional (3D) intensity modulated proton therapy treatment plan to be delivered by magnetic scanning may comprise thousands of discrete beam positions. This research presents the minimization of the total scan path length by application of a fast simulated annealing (FSA) optimization algorithm. Treatment plans for clinical prostate and head and neck cases were sequenced for continuous raster scanning in two ways, and the resulting scan path lengths were compared: (1) A simple back-and-forth, top-to-bottom (zigzag) succession, and (2) an optimized path produced as a solution of the FSA algorithm. Using a first approximation of the scanning dynamics, the delivery times for the scan sequences before and after path optimization were calculated for comparison. In these clinical examples, the FSA optimization shortened the total scan path length for the 3D target volumes by approximately 13%-56%. The number of extraneous spilled particles was correspondingly reduced by about 13%-54% due to the more efficient scanning maps that eliminated multiple crossings through regions of zero fluence. The relative decrease in delivery time due to path length minimization was estimated to be less than 1%, due to both a high scanning speed and time requirements that could not be altered by optimization (e.g., time required to change the beam energy). In a preliminary consideration of application to rescanning techniques, the decrease in delivery time was estimated to be 4%-20%

  20. Graphene Conductance Uniformity Mapping

    DEFF Research Database (Denmark)

    Buron, Jonas Christian Due; Petersen, Dirch Hjorth; Bøggild, Peter;

    2012-01-01

    We demonstrate a combination of micro four-point probe (M4PP) and non-contact terahertz time-domain spectroscopy (THz-TDS) measurements for centimeter scale quantitative mapping of the sheet conductance of large area chemical vapor deposited graphene films. Dual configuration M4PP measurements......, demonstrated on graphene for the first time, provide valuable statistical insight into the influence of microscale defects on the conductance, while THz-TDS has potential as a fast, non-contact metrology method for mapping of the spatially averaged nanoscopic conductance on wafer-scale graphene with scan times...... of less than a minute for a 4-in. wafer. The combination of M4PP and THz-TDS conductance measurements, supported by micro Raman spectroscopy and optical imaging, reveals that the film is electrically continuous on the nanoscopic scale with microscopic defects likely originating from the transfer process...

  1. Quadrature wavelength scanning interferometry.

    Science.gov (United States)

    Moschetti, Giuseppe; Forbes, Alistair; Leach, Richard K; Jiang, Xiang; O'Connor, Daniel

    2016-07-10

    A novel method to double the measurement range of wavelength scanning interferometery (WSI) is described. In WSI the measured optical path difference (OPD) is affected by a sign ambiguity, that is, from an interference signal it is not possible to distinguish whether the OPD is positive or negative. The sign ambiguity can be resolved by measuring an interference signal in quadrature. A method to obtain a quadrature interference signal for WSI is described, and a theoretical analysis of the advantages is reported. Simulations of the advantages of the technique and of signal errors due to nonideal quadrature are discussed. The analysis and simulation are supported by experimental measurements to show the improved performances. PMID:27409307

  2. A Scanning Cavity Microscope

    CERN Document Server

    Mader, Matthias; Hänsch, Theodor W; Hunger, David

    2014-01-01

    Imaging of the optical properties of individual nanosystems beyond fluorescence can provide a wealth of information. However, the minute signals for absorption and dispersion are challenging to observe, and only specialized techniques requiring sophisticated noise rejection are available. Here we use signal enhancement in a scanning optical microcavity to demonstrate ultra-sensitive imaging. Harnessing multiple interactions of probe light with a sample within an optical resonator, we achieve a 1700-fold signal enhancement compared to diffraction-limited microscopy. We demonstrate quantitative imaging of the extinction cross section of gold nanoparticles with a sensitivity below 1 nm2, we show a method to improve spatial resolution potentially below the diffraction limit by using higher order cavity modes, and we present measurements of the birefringence and extinction contrast of gold nanorods. The demonstrated simultaneous enhancement of absorptive and dispersive signals promises intriguing potential for opt...

  3. Telescopic horizon scanning.

    Science.gov (United States)

    Koenderink, Jan

    2014-12-20

    The problem of "distortionless" viewing with terrestrial telescopic systems (mainly "binoculars") remains problematic. The so called "globe effect" is only partially counteracted in modern designs. Theories addressing the phenomenon have never reached definitive closure. In this paper, we show that exact distortionless viewing with terrestrial telescopic systems is not possible in general, but that it is in principle possible in-very frequent in battle field and marine applications-the case of horizon scanning. However, this involves cylindrical optical elements. For opto-electronic systems, a full solution is more readily feasible. The solution involves a novel interpretation of the relevant constraints and objectives. For final design decisions, it is not necessary to rely on a corpus of psychophysical (or ergonomic) data, although one has to decide whether the instrument is intended as an extension of the eye or as a "pictorial" device. PMID:25608206

  4. Micro scanning probes

    CERN Document Server

    Niblock, T

    2001-01-01

    This thesis covers the design methodology, theory, modelling, fabrication and evaluation of a Micro-Scanning-Probe. The device is a thermally actuated bimorph quadrapod fabricated using Micro Electro Mechanical Systems technology. A quadrapod is a structure with four arms, in this case a planar structure with the four arms forming a cross which is dry etched out of a silicon diaphragm. Each arm has a layer of aluminium deposited on it forming a bimorph. Through heating each arm actuation is achieved in the plane of the quadrapod and the direction normal to it. Fabrication of the device has required the development of bulk micromachining techniques to handle post CMOS fabricated wafers and the patterning of thickly sputtered aluminium in bulk micro machined cavities. CMOS fabrication techniques were used to incorporate diodes onto the quadrapod arms for temperature measurement of the arms. Fine tungsten and silicon tips have also been fabricated to allow tunnelling between the tip and the platform at the centr...

  5. Phylogeographic Analyses of American Black Bears (Ursus americanus) Suggest Four Glacial Refugia and Complex Patterns of Postglacial Admixture.

    Science.gov (United States)

    Puckett, Emily E; Etter, Paul D; Johnson, Eric A; Eggert, Lori S

    2015-09-01

    Studies of species with continental distributions continue to identify intraspecific lineages despite continuous habitat. Lineages may form due to isolation by distance, adaptation, divergence across barriers, or genetic drift following range expansion. We investigated lineage diversification and admixture within American black bears (Ursus americanus) across their range using 22 k single nucleotide polymorphisms and mitochondrial DNA sequences. We identified three subcontinental nuclear clusters which we further divided into nine geographic regions: Alaskan (Alaska-East), eastern (Central Interior Highlands, Great Lakes, Northeast, Southeast), and western (Alaska-West, West, Pacific Coast, Southwest). We estimated that the western cluster diverged 67 ka, before eastern and Alaskan divergence 31 ka; these divergence dates contrasted with those from the mitochondrial genome where clades A and B diverged 1.07 Ma, and clades A-east and A-west diverged 169 ka. We combined estimates of divergence timing with hindcast species distribution models to infer glacial refugia for the species in Beringia, Pacific Northwest, Southwest, and Southeast. Our results show a complex arrangement of admixture due to expansion out of multiple refugia. The delineation of the genomic population clusters was inconsistent with the ranges for 16 previously described subspecies. Ranges for U. a. pugnax and U. a. cinnamomum were concordant with admixed clusters, calling into question how to order taxa below the species level. Additionally, our finding that U. a. floridanus has not diverged from U. a. americanus also suggests that morphology and genetics should be reanalyzed to assess taxonomic designations relevant to the conservation management of the species. PMID:25989983

  6. Experimental Research on Polycarboxylic Slump-retaining Admixture%聚羧酸减水剂的试验研究

    Institute of Scientific and Technical Information of China (English)

    廖国胜; 艾涛; 肖煜; 潘会

    2014-01-01

    Adopting methyl allyl polyoxyethylene ether (TPEG)and unsaturated carboxylic acid throught REDOX system synthetize the polycarboxylic slump-retaining admixture.The impact factors were researched of temperature,re-action time,acid alcohol ratio,dosage of initiator and molecular regulator to the polycarboxylic superplasticizer with slump retaining.In the circumstance of n(AA)∶n(Itaconic acid)∶n(Thioglycolic acid)∶n(TPEG)=1.7∶0.23∶0.005∶1,m(initiator)∶m(TPEG)=0.20%,reaction time is 4 h and temperaure is 45 ℃,the admixture has the best performance.%采用甲基烯丙基聚氧乙烯醚(TPEG)与不饱和羧酸在氧化还原体系下合成聚羧酸减水剂。研究了反应温度、反应时间、单体与不饱和羧酸摩尔比(酸醚比)、引发剂用量及分子量调节剂用量对聚羧酸减水剂性能的影响。在n(AA)∶n(Itaconic acid)∶n(Thioglycolic acid)∶n(TPEG)=1.7∶0.23∶0.005∶1,m(initiator)∶m(TPEG)=0.20%、反应时间4 h、反应温度45℃时,聚羧酸减水剂各项性能最佳。

  7. Multispecies Outcomes of Sympatric Speciation after Admixture with the Source Population in Two Radiations of Nicaraguan Crater Lake Cichlids

    Science.gov (United States)

    Kautt, Andreas F.; Machado-Schiaffino, Gonzalo; Meyer, Axel

    2016-01-01

    The formation of species in the absence of geographic barriers (i.e. sympatric speciation) remains one of the most controversial topics in evolutionary biology. While theoretical models have shown that this most extreme case of primary divergence-with-gene-flow is possible, only a handful of accepted empirical examples exist. And even for the most convincing examples uncertainties remain; complex histories of isolation and secondary contact can make species falsely appear to have originated by sympatric speciation. This alternative scenario is notoriously difficult to rule out. Midas cichlids inhabiting small and remote crater lakes in Nicaragua are traditionally considered to be one of the best examples of sympatric speciation and lend themselves to test the different evolutionary scenarios that could lead to apparent sympatric speciation since the system is relatively small and the source populations known. Here we reconstruct the evolutionary history of two small-scale radiations of Midas cichlids inhabiting crater lakes Apoyo and Xiloá through a comprehensive genomic data set. We find no signs of differential admixture of any of the sympatric species in the respective radiations. Together with coalescent simulations of different demographic models our results support a scenario of speciation that was initiated in sympatry and does not result from secondary contact of already partly diverged populations. Furthermore, several species seem to have diverged simultaneously, making Midas cichlids an empirical example of multispecies outcomes of sympatric speciation. Importantly, however, the demographic models strongly support an admixture event from the source population into both crater lakes shortly before the onset of the radiations within the lakes. This opens the possibility that the formation of reproductive barriers involved in sympatric speciation was facilitated by genetic variants that evolved in a period of isolation between the initial founding

  8. Scanning Emitter Lifetime Imaging Microscopy for Spontaneous Emission Control

    DEFF Research Database (Denmark)

    Frimmer, Martin; Chen, Yuntian; Koenderink, A. Femius

    2011-01-01

    We report an experimental technique to map and exploit the local density of optical states of arbitrary planar nanophotonic structures. The method relies on positioning a spontaneous emitter attached to a scanning probe deterministically and reversibly with respect to its photonic environment whi...

  9. Chemical imaging of biological systems with the scanning electrochemical microscope.

    Science.gov (United States)

    Gyurcsányi, Róbert E; Jágerszki, Gyula; Kiss, Gergely; Tóth, Klára

    2004-06-01

    A brief overview on recent advances in the application of scanning electrochemical microscopy (SECM) to the investigation of biological systems is presented. Special emphasis is given to the mapping of local enzyme activity by SECM, which is exemplified by relevant original systems. PMID:15110274

  10. Scan mirrors relay for high resolution laser scanning systems

    Science.gov (United States)

    Kessler, David

    2014-09-01

    Two dimensional beam deflection is often required in medical laser scanning systems such as OCT or confocal microscopy. Commonly two linear galvo mirrors are used for performance in terms of their large apertures and scan angles. The galvo mirrors are placed at the vicinity of entrance pupil of the scan lens with a "displacement distance" separating them. This distance limits the scan fields and/or reduces the effective aperture of the scan lens. Another option is to use a beam or pupil relay, and image one galvo mirror onto the other. However, beam (or pupil) relays are notoriously complicated, expensive and can add significant aberrations. This paper discusses a simple, all reflective, diffraction limited, color corrected, beam relay, capable of large scan angles and large deflecting mirrors. The design is based on a unique combination of an Offner configuration with a Schmidt aspheric corrector. The design is highly corrected up to large scan mirrors and large scan angles down to milliwaves of aberrations. It allows significantly larger scan field and or scan lenses with higher numerical aperture as compared with scanners using galvos separated by the displacement distance. While this relay is of exceptionally high performance, it has one element located where the beam is focused which may present a problem for high power lasers. Thus modifications of the above design are introduced where the beam is focused in mid air thus making it usable for high power systems such including laser marking and fabrication systems.

  11. Affective Maps

    DEFF Research Database (Denmark)

    Salovaara-Moring, Inka

    . In particular, mapping environmental damage, endangered species, and human made disasters has become one of the focal point of affective knowledge production. These ‘more-than-humangeographies’ practices include notions of species, space and territory, and movement towards a new political ecology. This type...... of environmental knowledge production. It uses InfoAmazonia, the databased platform on Amazon rainforests, as an example of affective geo-visualization within information mapping that enhances embodiment in the experience of the information. Amazonia is defined as a digitally created affective (map)space within...

  12. Implementation of ionoluminescence in the AGLAE scanning external microprobe

    Energy Technology Data Exchange (ETDEWEB)

    Pichon, L., E-mail: laurent.pichon@culture.gouv.fr [Centre de recherche et de restauration des musées de France, C2RMF, Palais du Louvre – Porte des Lions, 14 Quai François Mitterrand, 75001 Paris (France); Fédération de recherche NewAGLAE, FR3506 CNRS/Ministère de la Culture/UPMC, Palais du Louvre, 75001 Paris (France); Calligaro, T.; Gonzalez, V. [Centre de recherche et de restauration des musées de France, C2RMF, Palais du Louvre – Porte des Lions, 14 Quai François Mitterrand, 75001 Paris (France); PSL Research University, Chimie ParisTech-CNRS, Institut de Recherche Chimie Paris, UMR8247, 75005 Paris (France); Lemasson, Q.; Moignard, B.; Pacheco, C. [Centre de recherche et de restauration des musées de France, C2RMF, Palais du Louvre – Porte des Lions, 14 Quai François Mitterrand, 75001 Paris (France); Fédération de recherche NewAGLAE, FR3506 CNRS/Ministère de la Culture/UPMC, Palais du Louvre, 75001 Paris (France)

    2015-04-01

    The scope of this work is to present the implementation of an IBIL imaging system in the scanning external microprobe of the AGLAE facility so as to correlate luminescence and composition maps provided by PIXE, RBS and PIGE. The challenging integration of the optical spectrometer, due to incompatibility of acquisition timings and data formats with the other IBA channels has motivated the development of a specific acquisition system. This article details the IBIL setup and explains the technical solutions retained for the coupling of IBIL with IBA techniques in order to produce fast and large IBIL-IBA maps. The IBIL maps stored in the same format as the PIXE, RBS and PIGE ones can be visualised and compared using the dedicated AGLAEmap program or the PyMCA processing package. An example of such a coupled mapping on Mesoamerican jade is presented to emphasise the interest of performing simultaneously IBA and IBIL large mappings.

  13. Association Mapping for Drought Tolerance of Rice (Oryza sativa L.) at Vegetative Stage

    Institute of Scientific and Technical Information of China (English)

    Yulong XIAO; Chuanyuan YU; Jianguo LEI; Quirino D; DELA CRUZ; Jonalyn M.YABES; Dindo A.TABANAo

    2012-01-01

    [Objective] This study aimed to identify possible quantitative trait loci (QTL) for vegetative drought tolerance traits of rice (Oryza sativa L.). [Method] A total of 184 rice genotypes were field screened and 156 SSR markers randomly distributed at each 3 Mb bin were used through genome-wide scanning method and association analysis to detect QTLs for vegetative drought tolerance traits leaf rolling (LER), leaf drying (LED) and drought recovery rate (DRR). [Result] The experimental rice geno- types showed varied response under vegetative drought, LER, LED and DRR were highly correlated. Population structure was detected at K=3 and K=7, certain extent of admixture existed in the experimental rice genotypes, relative kinship of the rice genotypes ranged from 0 to 0.924 5. Significant linkage disequilibrium among SSR markers was detected. Sixteen SSR markers have been detected to be associated with vegetative drought tolerance traits, four for LER, eight for LED and four for DDR. Most of the markers were associated with more than one trait, indicating a single mechanism might involve in expression of several related traits, i.e. osmotic adjustment. RM107 (Chr.9) was associated with all the three traits and fell exactly within or closely nearby to previous reported regions, was a major QTL for vegeta- tive drought tolerance, RM477 (Chr.8) was significantly associated with DRR and ex- tremely significantly associated with LER was probably another major QTL for vege- tative drought tolerance. [Conclusion] Association mapping is a very effective method for describing complex traits like drought tolerance.

  14. Mapping Biodiversity.

    Science.gov (United States)

    World Wildlife Fund, Washington, DC.

    This document features a lesson plan that examines how maps help scientists protect biodiversity and how plants and animals are adapted to specific ecoregions by comparing biome, ecoregion, and habitat. Samples of instruction and assessment are included. (KHR)

  15. Rethinking maps

    OpenAIRE

    Kitchin, Rob; Dodge, Martin

    2007-01-01

    In this paper we argue that cartography is profitably conceived as a processual, rather than representational, science. Building on recent analysis concerning the philosophical underpinnings of cartography we question the ontological security of maps, contending that it is productive to rethink cartography as ontogenetic in nature; that is maps emerge through practices and have no secure ontological status. Drawing on the concepts of transduction and technicity we contend that ...

  16. Radionuclide brain scanning

    International Nuclear Information System (INIS)

    At one stage of medical imaging development, radionuclide brain scanning was the only technique available for imaging of the brain. Advent of CT and MRI pushed it to the background. It regained some of the grounds lost to ''allied advances'' with the introduction of brain perfusion radiopharmaceuticals. Positron emission tomography is a promising functional imaging modality that at present will remain as a research tool in special centres in developed countries. However, clinically useful developments will gradually percolate from PET to SPECT. The non-nuclear imaging methods are totally instrument dependent; they are somewhat like escalators, which can go that far and no further. Nuclear imaging has an unlimited scope for advance because of the new developments in radiopharmaceuticals. As the introduction of a radiopharmaceutical is less costly than buying new instruments, the recent advances in nuclear imaging are gradually perfusing through the developing countries also. Therefore, it is essential to follow very closely PET developments because what is research today might become routine tomorrow

  17. LANL Robotic Vessel Scanning

    Energy Technology Data Exchange (ETDEWEB)

    Webber, Nels W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-25

    Los Alamos National Laboratory in J-1 DARHT Operations Group uses 6ft spherical vessels to contain hazardous materials produced in a hydrodynamic experiment. These contaminated vessels must be analyzed by means of a worker entering the vessel to locate, measure, and document every penetration mark on the vessel. If the worker can be replaced by a highly automated robotic system with a high precision scanner, it will eliminate the risks to the worker and provide management with an accurate 3D model of the vessel presenting the existing damage with the flexibility to manipulate the model for better and more in-depth assessment.The project was successful in meeting the primary goal of installing an automated system which scanned a 6ft vessel with an elapsed time of 45 minutes. This robotic system reduces the total time for the original scope of work by 75 minutes and results in excellent data accumulation and transmission to the 3D model imaging program.

  18. Effect of Mineral Admixtures on Sulfate Attack Resistance of Cement-Based Materials%矿物掺合料改善水泥基材料抗硫酸盐侵蚀性能的微观分析

    Institute of Scientific and Technical Information of China (English)

    李华; 孙伟; 左晓宝

    2012-01-01

    采用CT、X射线衍射、扫描电子显微镜等测试方法,通过对不掺矿物掺合料以及掺30%粉煤灰或50%矿渣的水泥净浆、水泥砂浆在室温下5%Na2SO4溶液中浸泡2a后的宏观破坏形态和浆体组分及浆体形貌的分析,从微观层次上研究了矿物掺合料对水泥基材料抗硫酸盐侵蚀破坏的影响。结果表明:侵蚀后不掺矿物掺合料的试件由表及里呈现三层不同侵蚀状态,即表层石膏区、中层钙矾石区以及内层未侵蚀区。矿物掺合料的C3A含量稀释效应、火山灰反应以及微集料填充效应协同作用的结果使得试件的抗硫酸钠溶液侵蚀破坏性能显著提高。但矿渣中活性Al3+含量较高,能与SO42–反应生成大量钙矾石晶体,掺量不当会对试件的抗硫酸钠侵蚀性能不利。砂集料有阻碍微裂纹发展及增大试样内部不均匀性的相反作用,集料的含量、颗粒尺寸及分布对水泥基材料的抗硫酸钠侵蚀破坏性能的影响是以后研究中需关注的问题。%The appearance observation, mineral composition, as well ;as microstructure morphology towards various cement pastes and motars with and without 30% fly ash or 50% slag dipped in 5% Na2SO4 solution at room temperature for 2 years were characterized by X-CT, X-ray diffraction and scanning electron microscopy to investigate the effects of mineral admixtures such as slag and fly ash on the sulfate resistance performance of cement-based materials from the micro-level angle. The results show that the specimens without mineral admixtures appear three different attack states from surface to inside, i.e., the gypsum area, the ettringite area and the unaffected area. Mineral admixtures can improve the sulfate resistance performance of cement-based materials via synergy effect of reducing C3A content, pozzolanic reaction and micro-aggregates filling. However, the improper content of slag in cement-based mate- rials has a negative effect on

  19. Voltammetric scanning electrochemical cell microscopy: dynamic imaging of hydrazine electro-oxidation on platinum electrodes

    NARCIS (Netherlands)

    Chen, C.-H.; Jacobse, L.; McKelvey, K.; Lai, S.C.S.; Koper, M.T.M.; Unwin, P.R.

    2015-01-01

    Voltammetric scanning electrochemical cell microscopy (SECCM) incorporates cyclic voltammetry measurements in the SECCM imaging protocol, by recording electrochemical currents in a wide potential window at each pixel in a map. This provides much more information compared to traditional fixed potenti

  20. Hyperchromatic laser scanning cytometry

    Science.gov (United States)

    Tárnok, Attila; Mittag, Anja

    2007-02-01

    In the emerging fields of high-content and high-throughput single cell analysis for Systems Biology and Cytomics multi- and polychromatic analysis of biological specimens has become increasingly important. Combining different technologies and staining methods polychromatic analysis (i.e. using 8 or more fluorescent colors at a time) can be pushed forward to measure anything stainable in a cell, an approach termed hyperchromatic cytometry. For cytometric cell analysis microscope based Slide Based Cytometry (SBC) technologies are ideal as, unlike flow cytometry, they are non-consumptive, i.e. the analyzed sample is fixed on the slide. Based on the feature of relocation identical cells can be subsequently reanalyzed. In this manner data on the single cell level after manipulation steps can be collected. In this overview various components for hyperchromatic cytometry are demonstrated for a SBC instrument, the Laser Scanning Cytometer (Compucyte Corp., Cambridge, MA): 1) polychromatic cytometry, 2) iterative restaining (using the same fluorochrome for restaining and subsequent reanalysis), 3) differential photobleaching (differentiating fluorochromes by their different photostability), 4) photoactivation (activating fluorescent nanoparticles or photocaged dyes), and 5) photodestruction (destruction of FRET dyes). With the intelligent combination of several of these techniques hyperchromatic cytometry allows to quantify and analyze virtually all components of relevance on the identical cell. The combination of high-throughput and high-content SBC analysis with high-resolution confocal imaging allows clear verification of phenotypically distinct subpopulations of cells with structural information. The information gained per specimen is only limited by the number of available antibodies and by sterical hindrance.

  1. Re-scan confocal microscopy: scanning twice for better resolution

    NARCIS (Netherlands)

    G.M.R. De Luca; R.M.P. Breedijk; R.A.J. Brandt; C.H.C. Zeelenberg; B.E. de Jong; W. Timmermans; L.N. Azar; R.A. Hoebe; S. Stallinga; E.M.M. Manders

    2013-01-01

    We present a new super-resolution technique, Re-scan Confocal Microscopy (RCM), based on standard confocal microscopy extended with an optical (re-scanning) unit that projects the image directly on a CCD-camera. This new microscope has improved lateral resolution and strongly improved sensitivity wh

  2. Mapping Deeply

    Directory of Open Access Journals (Sweden)

    Denis Wood

    2015-08-01

    Full Text Available This is a description of an avant la lettre deep mapping project carried out by a geographer and a number of landscape architecture students in the early 1980s. Although humanists seem to take the “mapping” in deep mapping more metaphorically than cartographically, in this neighborhood mapping project, the mapmaking was taken literally, with the goal of producing an atlas of the neighborhood. In this, the neighborhood was construed as a transformer, turning the stuff of the world (gas, water, electricity into the stuff of individual lives (sidewalk graffiti, wind chimes, barking dogs, and vice versa. Maps in the central transformer section of the atlas were to have charted this process in action, as in one showing the route of an individual newspaper into the neighborhood, then through the neighborhood to a home, and finally, as trash, out of the neighborhood in a garbage truck; though few of these had been completed when the project concluded in 1986. Resurrected in 1998 in an episode on Ira Glass’ This American Life, the atlas was finally published, as Everything Sings: Maps for a Narrative Atlas, in 2010 (and an expanded edition in 2013.

  3. Parametric mapping

    Science.gov (United States)

    Branch, Allan C.

    1998-01-01

    Parametric mapping (PM) lies midway between older and proven artificial landmark based guidance systems and yet to be realized vision based guidance systems. It is a simple yet effective natural landmark recognition system offering freedom from the need for enhancements to the environment. Development of PM systems can be inexpensive and rapid and they are starting to appear in commercial and industrial applications. Together with a description of the structural framework developed to generically describe robot mobility, this paper illustrates clearly the parts of any mobile robot navigation and guidance system and their interrelationships. Among other things, the importance of the richness of the reference map, and not necessarily the sensor map, is introduced, the benefits of dynamic path planners to alleviate the need for separate object avoidance, and the independence of the PM system to the type of sensor input is shown.

  4. CALS Mapping

    DEFF Research Database (Denmark)

    Collin, Ib; Nielsen, Povl Holm; Larsen, Michael Holm

    1998-01-01

    To enhance the industrial applications of CALS, CALS Center Danmark has developed a cost efficient and transparent assessment, CALS Mapping, to uncover the potential of CALS - primarily dedicated to small and medium sized enterprises. The idea behind CALS Mapping is that the CALS State...... of the enterprise is compared with a Reference Enterprise Model (REM). The REM is a CALS idealised enterprise providing full product support throughout the extended enterprise and containing different manufacturing aspects, e.g. component industry, process industry, and one-piece production. This CALS idealised...... enterprise is, when applied in a given organisation modified with respect to the industry regarded, hence irrelevant measure parameters are eliminated to avoid redundancy. This assessment of CALS Mapping, quantify the CALS potential of an organisation with the purpose of providing decision support to the top...

  5. Techniques Which Aid in Quantitative Interpretation of Scan Data

    International Nuclear Information System (INIS)

    This paper discusses a range of techniques which assist in evaluating and interpreting scanning read-out display. This range extends from simple internal calibration for photographic read-out to fairly elaborate auxiliary equipment for presentation of accumulated digital scan information to a computer programme. The direct and remarkably useful method of using a random pulse generator to produce a calibrated step-wedge of spots, which are projected on to a film by the same projection light source as is used during the scan, allows the viewer to compare exposure densities of regions of interest on the scan to similar regions on the wedge which are calibrated directly in count-rate units. Auxiliary equipment, such as a multichannel analyser used in the multiscaling mode, permits the accumulation of digital information for a ''total count per scan line'' display for each index step. Small animal scans have been made which accumulate and display ''counts per scan line'' for each index step. This produces an accurate quantitative measure of the distribution of activity over the animal and a profile display of activity similar to the slit scan display of a linear scanning system. The same multiscaling technique is carried further by accumulating digital information for a ''count per unit area'' display. A profile curve is obtained for each scan line of each index step. From this it is possible to visualize or construct an area profile of count-rate. Scan displays with or without contrast enhancement and with or without ''time lag'' from integrating circuitry and scans with various spot sizes and shapes have been produced under identical statistical conditions by means of multiple read-outs while scanning a phantom with a single-detector system. Direct comparison of displays combined with the ''count per unit area'' mapping technique aid in the interpretation of scan results. 'Precise position information must be included with the data record. Computations of percentage

  6. Bone Densitometry (Bone Density Scan)

    Science.gov (United States)

    ... of DXA Bone Densitometry? What is a Bone Density Scan (DXA)? Bone density scanning, also called dual-energy x-ray absorptiometry ( ... is today's established standard for measuring bone mineral density (BMD). An x-ray (radiograph) is a noninvasive ...

  7. Improvement Concretes Outside Admixture and Cement Compatible Measure%论改善混凝土外掺剂与水泥适应性的措施

    Institute of Scientific and Technical Information of China (English)

    赵小萍

    2009-01-01

    文章论述了水泥与外加剂的适应性是影响混凝土质量的重要因素,提出几点改善措施:即新型高性能减水荆的开发应用、外加剂的复合使用、减水剂的掺入方法、适当"增硫法"和适当调整混凝土配合比.%This article elaborated the cement and the admixture compatibility is affects the concretes quality the important attribute, proposes sev-eral improvement measures: new high performance water reducing agent development application, admixture compound use, the water reducing a-gent mixes in the method, suitable "increases the sulfur law", appropriate readjustment proportioning of concrete.

  8. Standard test method for determining effects of chemical admixtures on corrosion of embedded steel reinforcement in concrete exposed to chloride environments

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This test method covers a procedure for determining the effects of chemical admixtures on the corrosion of metals in concrete. This test method can be used to evaluate materials intended to inhibit chloride-induced corrosion of steel in concrete. It can also be used to evaluate the corrosivity of admixtures in a chloride environment. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  9. The isospin admixture of the ground state and the properties of the isobar analog resonances in medium and heavy mass nuclei

    Indian Academy of Sciences (India)

    D I Salmov; T Babacan; A Kücükbursa; S Ünlü; İ Maraṣ

    2006-06-01

    Within the framework of quasiparticle random phase approximation (QRPA), Pyatov–Salamov method [23] for the self-consistent determination of the isovector effective interaction strength parameter, restoring a broken isotopic symmetry for the nuclear part of the Hamiltonian, is used. The isospin admixtures in the ground state of the parent nucleus, and the isospin structure of the isobar analog resonance (IAR) state were investigated with the inclusion of the pairing correlations between nucleons for the medium and heavy mass regions: 80 < < 90, 102 < < 124, and 204 < < 214. It was determined that the influence of the pairing interaction between nucleons on the isospin admixtures in the ground state and the isospin structure of the IAR state is more pronounced for the light isotopes ( ≈ ) of the investigated nuclei.

  10. Scanning deep level transient spectroscopy using an MeV ion microprobe

    Energy Technology Data Exchange (ETDEWEB)

    Laird, J.S.; Bardos, R.A.; Saint, A.; Moloney, G.M.; Legge, G.F.J. [Melbourne Univ., Parkville, VIC (Australia)

    1993-12-31

    Traditionally the scanning ion microprobe has given little or no information regarding the electronic structure of materials in particular semiconductors. A new imaging technique called Scanning Ion Deep Level Transient Spectroscopy (SIDLTS) is presented which is able to spatially map alterations in the band gap structure of materials by lattice defects or impurities. 3 refs., 2 figs.

  11. Autosomal and X-linked single nucleotide polymorphisms reveal a steep Asian-Melanesian ancestry cline in eastern Indonesia and a sex bias in admixture rates.

    Science.gov (United States)

    Cox, Murray P; Karafet, Tatiana M; Lansing, J Stephen; Sudoyo, Herawati; Hammer, Michael F

    2010-05-22

    The geographical region between mainland Asia and New Guinea is characterized by numerous small islands with isolated human populations. Phenotypically, groups in the west are similar to their neighbours in mainland Southeast Asia, eastern groups near New Guinea are similar to Melanesians, and intervening populations are intermediate in appearance. A long-standing question is whether this pattern primarily reflects mixing between groups with distinct origins or whether natural selection has shaped this range of variation by acting differentially on populations across the region. To address this question, we genotyped a set of 37 single nucleotide polymorphisms that are evolutionarily independent, putatively neutral and highly informative for Asian-Melanesian ancestry in 1430 individuals from 60 populations spanning mainland Asia to Melanesia. Admixture analysis reveals a sharp transition from Asian to Melanesian genetic variants over a narrow geographical region in eastern Indonesia. Interestingly, this admixture cline roughly corresponds to the human phenotypic boundary noted by Alfred Russell Wallace in 1869. We conclude that this phenotypic gradient probably reflects mixing of two long-separated ancestral source populations-one descended from the initial Melanesian-like inhabitants of the region, and the other related to Asian groups that immigrated during the Paleolithic and/or with the spread of agriculture. A higher frequency of Asian X-linked markers relative to autosomal markers throughout the transition zone suggests that the admixture process was sex-biased, either favouring a westward expansion of patrilocal Melanesian groups or an eastward expansion of matrilocal Asian immigrants. The matrilocal marriage practices that dominated early Austronesian societies may be one factor contributing to this observed sex bias in admixture rates.

  12. Autosomal and X-linked single nucleotide polymorphisms reveal a steep Asian–Melanesian ancestry cline in eastern Indonesia and a sex bias in admixture rates

    Science.gov (United States)

    Cox, Murray P.; Karafet, Tatiana M.; Lansing, J. Stephen; Sudoyo, Herawati; Hammer, Michael F.

    2010-01-01

    The geographical region between mainland Asia and New Guinea is characterized by numerous small islands with isolated human populations. Phenotypically, groups in the west are similar to their neighbours in mainland Southeast Asia, eastern groups near New Guinea are similar to Melanesians, and intervening populations are intermediate in appearance. A long-standing question is whether this pattern primarily reflects mixing between groups with distinct origins or whether natural selection has shaped this range of variation by acting differentially on populations across the region. To address this question, we genotyped a set of 37 single nucleotide polymorphisms that are evolutionarily independent, putatively neutral and highly informative for Asian–Melanesian ancestry in 1430 individuals from 60 populations spanning mainland Asia to Melanesia. Admixture analysis reveals a sharp transition from Asian to Melanesian genetic variants over a narrow geographical region in eastern Indonesia. Interestingly, this admixture cline roughly corresponds to the human phenotypic boundary noted by Alfred Russell Wallace in 1869. We conclude that this phenotypic gradient probably reflects mixing of two long-separated ancestral source populations—one descended from the initial Melanesian-like inhabitants of the region, and the other related to Asian groups that immigrated during the Paleolithic and/or with the spread of agriculture. A higher frequency of Asian X-linked markers relative to autosomal markers throughout the transition zone suggests that the admixture process was sex-biased, either favouring a westward expansion of patrilocal Melanesian groups or an eastward expansion of matrilocal Asian immigrants. The matrilocal marriage practices that dominated early Austronesian societies may be one factor contributing to this observed sex bias in admixture rates. PMID:20106848

  13. Northern range expansion of European populations of the wasp spider Argiope bruennichi is associated with global warming-correlated genetic admixture and population-specific temperature adaptations.

    Science.gov (United States)

    Krehenwinkel, Henrik; Tautz, Diethard

    2013-04-01

    Poleward range expansions are observed for an increasing number of species, which may be an effect of global warming during the past decades. However, it is still not clear in how far these expansions reflect simple geographical shifts of species ranges, or whether new genetic adaptations play a role as well. Here, we analyse the expansion of the wasp spider Argiope bruennichi into Northern Europe during the last century. We have used a range-wide sampling of contemporary populations and historical specimens from museums to trace the phylogeography and genetic changes associated with the range shift. Based on the analysis of mitochondrial, microsatellite and SNP markers, we observe a higher level of genetic diversity in the expanding populations, apparently due to admixture of formerly isolated lineages. Using reciprocal transplant experiments for testing overwintering tolerance, as well as temperature preference and tolerance tests in the laboratory, we find that the invading spiders have possibly shifted their temperature niche. This may be a key adaptation for survival in Northern latitudes. The museum samples allow a reconstruction of the invasion's genetic history. A first, small-scale range shift started around 1930, in parallel with the onset of global warming. A more massive invasion of Northern Europe associated with genetic admixture and morphological changes occurred in later decades. We suggest that the latter range expansion into far Northern latitudes may be a consequence of the admixture that provided the genetic material for adaptations to new environmental regimes. Hence, global warming could have facilitated the initial admixture of populations and this resulted in genetic lineages with new habitat preferences. PMID:23496675

  14. Research status of mine tailings used as cement admixture%尾矿作水泥混合材的研究现状

    Institute of Scientific and Technical Information of China (English)

    谭明洋; 吕宪俊; 姜梅芬

    2015-01-01

    概述了近年来尾矿在水泥中的应用及研究现状,并据此提出了今后尾矿用作水泥混合材的研究方向。%Summarized the application status and the up-to-date progress of mine tailings used in cement,and further research topics for the application performance of cement admixtures were proposed accordingly.

  15. The effects of Propofol-Thiopental admixture on hemodynamic changes, pain on injection, and hypnotic dose at the time of anesthesia induction: a prospective study

    Directory of Open Access Journals (Sweden)

    Soltani Mohammadi S

    2007-09-01

    Full Text Available   Background: Propofol and Thiopental are intravenous anesthetics having relatively different hemodynamic influences and adverse effects. In addition, there is significant pain on intravenous injection of propofol. This study was performed to examine the effects of Propofol-Thiopental admixture on hemodynamic variables, pain on injection and hypnotic dose at the time of induction of general anesthesia.Methods: One hundred and twenty-five ASA I or II patients scheduled for elective surgery were randomized into four groups for induction of anesthesia in a double-blinded manner. With an original concentration of Propofol of 1% and that of Thiopental of 2.5%, we used these drugs in each group as follows: group P100: Propofol alone; group P75: ¾ Propofol and ¼ thiopental (volume/volume; group P50: ½ Propofol and ½ thiopental; group T100: Thiopental alone (control group. Hemodynamic variables (before and after induction, score of pain on injection and hypnotic doses were recorded and statistically analyzed.Results: Admixture of Thiopental and Propofol reduces the injection pain of Propofol, as admixtures P75 and P50 were significantly less painful on injection than P100. Induction of hypnosis was significantly more rapid in group T100 than in groups P100 and P75. The interaction of Propofol and Thiopental with regard to their hypnotic effect is additive. Therefore a reduction in the dose of one was compensated by proportional increase in the dose of the other drug for a hypnotic effect. After anesthesia induction, systolic and diastolic blood pressures were significantly lower in group P100 than in groups P75, P50 and T100. The heart rate after laryngoscopy and tracheal intubation was significantly lower in group P100 than in groups P50 and T100.Conclusion: Propofol-Thiopental admixture causes minimal pain on injection for intravenous induction of anesthesia with modified hemodynamic effects in comparison with each drug when used separately.

  16. Mapping Resilience

    DEFF Research Database (Denmark)

    Carruth, Susan

    2015-01-01

    relationship between resilience and energy planning, suggesting that planning in, and with, time is a core necessity in this domain. It then reviews four examples of graphically mapping with time, highlighting some of the key challenges, before tentatively proposing a graphical language to be employed by...

  17. Mole Mapping.

    Science.gov (United States)

    Crippen, Kent J.; Curtright, Robert D.; Brooks, David W.

    2000-01-01

    The abstract nature of the mole and its applications to problem solving make learning the concept difficult for students, and teaching the concept challenging for teachers. Presents activities that use concept maps and graphing calculators as tools for solving mole problems. (ASK)

  18. Mapping filmmaking

    DEFF Research Database (Denmark)

    Gilje, Øystein; Frølunde, Lisbeth; Lindstrand, Fredrik;

    2010-01-01

    This chapter concerns mapping patterns in regards to how young filmmakers (age 15 – 20) in the Scandinavian countries learn about filmmaking. To uncover the patterns, we present portraits of four young filmmakers who participated in the Scandinavian research project Making a filmmaker. The focus ...

  19. Participatory maps

    DEFF Research Database (Denmark)

    Salovaara-Moring, Inka

    looks at computer-assisted cartography as part of environmental knowledge production. It uses InfoAmazonia, the databased platform on Amazon rainforests, as an example of affective geo-visualization within information mapping that enhances embodiment in the experience of the information. Amazonia...

  20. Energetic map

    International Nuclear Information System (INIS)

    This report explains the energetic map of Uruguay as well as the different systems that delimits political frontiers in the region. The electrical system importance is due to the electricity, oil and derived , natural gas, potential study, biofuels, wind and solar energy

  1. QTL IciMapping:Integrated software for genetic linkage map construction and quantitative trait locus mapping in biparental populations

    Institute of Scientific and Technical Information of China (English)

    Lei Meng; Huihui Li; Luyan Zhang; Jiankang Wang

    2015-01-01

    QTL IciMapping is freely available public software capable of building high-density linkage maps and mapping quantitative trait loci (QTL) in biparental populations. Eight func-tionalities are integrated in this software package: (1) BIN:binning of redundant markers;(2) MAP: construction of linkage maps in biparental populations; (3) CMP: consensus map construction from multiple linkage maps sharing common markers; (4) SDL: mapping of segregation distortion loci;(5) BIP:mapping of additive, dominant, and digenic epistasis genes;(6) MET:QTL-by-environment interaction analysis;(7) CSL:mapping of additive and digenic epistasis genes with chromosome segment substitution lines; and (8) NAM: QTL mapping in NAM populations. Input files can be arranged in plain text, MS Excel 2003, or MS Excel 2007 formats. Output files have the same prefix name as the input but with different extensions. As examples, there are two output files in BIN, one for summarizing the identified bin groups and deleted markers in each bin, and the other for using the MAP functionality. Eight output files are generated by MAP, including summary of the completed linkage maps, Mendelian ratio test of individual markers, estimates of recombination frequencies, LOD scores, and genetic distances, and the input files for using the BIP, SDL, and MET functionalities. More than 30 output files are generated by BIP, including results at all scanning positions, identified QTL, permutation tests, and detection powers for up to six mapping methods. Three supplementary tools have also been developed to display completed genetic linkage maps, to estimate recombination frequency between two loci, and to perform analysis of variance for multi-environmental trials.

  2. QTL IciMapping:Integrated software for genetic linkage map construction and quantitative trait locus mapping in biparental populations

    Institute of Scientific and Technical Information of China (English)

    Lei; Meng; Huihui; Li; Luyan; Zhang; Jiankang; Wang

    2015-01-01

    QTL Ici Mapping is freely available public software capable of building high-density linkage maps and mapping quantitative trait loci(QTL) in biparental populations. Eight functionalities are integrated in this software package:(1) BIN: binning of redundant markers;(2) MAP: construction of linkage maps in biparental populations;(3) CMP: consensus map construction from multiple linkage maps sharing common markers;(4) SDL: mapping of segregation distortion loci;(5) BIP: mapping of additive, dominant, and digenic epistasis genes;(6) MET: QTL-by-environment interaction analysis;(7) CSL: mapping of additive and digenic epistasis genes with chromosome segment substitution lines; and(8) NAM: QTL mapping in NAM populations. Input files can be arranged in plain text, MS Excel 2003, or MS Excel 2007 formats. Output files have the same prefix name as the input but with different extensions. As examples, there are two output files in BIN, one for summarizing the identified bin groups and deleted markers in each bin, and the other for using the MAP functionality. Eight output files are generated by MAP, including summary of the completed linkage maps, Mendelian ratio test of individual markers, estimates of recombination frequencies, LOD scores, and genetic distances, and the input files for using the BIP, SDL,and MET functionalities. More than 30 output files are generated by BIP, including results at all scanning positions, identified QTL, permutation tests, and detection powers for up to six mapping methods. Three supplementary tools have also been developed to display completed genetic linkage maps, to estimate recombination frequency between two loci,and to perform analysis of variance for multi-environmental trials.

  3. Spatial distribution maps for benthic communities

    DEFF Research Database (Denmark)

    Sørensen, Per S.

    1999-01-01

    ecosystems, were selected. These species are supposed to be good indicators of marine ecosystem health. The hydroacoustic measurements comprise preprocessed echo sounder recordings and side-scan sonar data forming a large and unique collection of datasets based on 4 field campaigns in Øresund...... of the distribution maps and to be combined with biogeochemical models describing spatiotemporal population dynamics. Finally, the use of side-scan sonar data is illustrated in a data fusion exercise combining side-scan sonar data with the results based on echo sounder measurements. The feasible use of side......-scan sonar for mapping of benthic communities remains an open task to be studied in the future. The data processing methodology developed is a contribution to the emerging field of hydroacoustic marine biology. The method of penalised maximum pseudo-likelihood for estimation of the Ising model under a huge...

  4. Progress in Lignin-based Concrete Admixtures%含木质素基混凝土外加剂的研究进展

    Institute of Scientific and Technical Information of China (English)

    谌凡琪

    2012-01-01

    综述了木质素在混凝土外加剂中的应用。工业木质素,尤其是木质素磺酸盐,可以充当混凝土减水剂、缓凝剂、引气剂和泵送剂。由于未经改性的工业木质素性能不够理想,为了提高木质素基混凝土添加剂的性能,宜对其进行适当的改性。碱木质素经过氧化、磺化、磺甲基化、接枝共聚等改性后,可以得到具有良好性能的混凝土外加剂。%The applications of lignin derivatives in concrete admixtures are reviewed. Technical lignins, especially lignosulfonates, can serve as concrete water reducers, retarders, air entraining agents and pumping agents. The performance of lignin is not good. Some appropriate modifications are sometimes required in order to improve the performance of the lignin-based concrete admixtures. Lignin-based concrete admixtures with good performaces can be obtained fxom alkali lignin after modifications such as oxidation, sulfonation, sulfomethylation and graft copolymerization.

  5. Investigations regarding the mass budget in the propagation of a passive admixture from a line source; Untersuchungen zur Stoffbilanz bei der Ausbreitung einer passiven Beimengung aus einer Linienquelle

    Energy Technology Data Exchange (ETDEWEB)

    Wenzel, A. [Brandenburgische Technische Univ. Cottbus (Germany). Inst. fuer Boden-, Luft- und Gewaesserschutz

    1998-01-01

    Under stationary conditions, passive admixtures are transported by advection and by vertical as well as horizontal turbulent diffusion. The importance of individual contributions for the exchange of passive admixtures emanating from a straight line source with a constant source strength under neutral stratification conditions is discussed. For this purpose, all terms of the mass budget for a control volume around a straight line source are calculated using a stochastic Lagrange model (LS), whose properties are discussed. As a test for the LS model, the vertical and horizontal mass flows in the soil layer are simulated and compared with SANA data. The mass flows calculated for the propagation of a passive admixture from a line source are evaluated regarding their share of the mass budget. (orig.) [Deutsch] Unter stationaeren Bedingungen erfolgt der Transport von passiven Beimengungen durch Advektion sowie vertikale und horizontale turbulente Diffusion. Die Bedeutung der einzelnen Beitraege fuer den Austausch von passiven Beimengungen, die von einer geraden Linienquelle mit konstanter Quellstaerke unter neutralen Schichtungsbedingungen ausgehen, wird diskutiert. Dazu werden mit einem Lagrangeschen stochastischen (LS) Modell, dessen Eigenschaften besprochen werden, alle Terme der Stoffbilanz fuer ein Kontrollvolumen um eine gerade Linienquelle berechnet. Als Test fuer das LS-Modell werden die vertikalen und die horizontalen Stofffluesse in der Bodenschicht simuliert und mit SANA-Daten verglichen. Die fuer die Ausbreitung einer passiven Beimengung von einer Linienquelle berechneten Massenfluesse, werden hinsichtlich ihres Anteils an der Stoffbilanz ausgewertet. (orig.)

  6. Brief talk about quality control of various aspects in pharmacy intravenous admixture service%浅谈 PIVAS 工作中各环节质量控制

    Institute of Scientific and Technical Information of China (English)

    石锐

    2015-01-01

    目的:通过分析总结静脉用药调配中心(PIVAS)各工作环节注意事项,为提高工作质量提供参考。方法:分析医嘱审核、摆药、配制等环节,提出针对性的解决措施。结果:加强医嘱审核、科学合理摆药、严密把握配制关等环节可进一步提高各环节质量。结论:通过各工作环节质量控制,为临床提供安全输液的静脉用药。%Objective:To summarize and analyze the points for attention of all work aspects in pharmacy intravenous ad-mixture service(PIVAS),to provide a reference for improve work quality. Methods:By analyzing prescriptions analysis,drug dispensing and admixture,to come up with purposeful solving measures. Results:By means of reinforcing prescription analysis, scientific and reasonable drug dispensing and strict drug admixture and so on,all aspects of work can be further improved. Con-clusion:According to the improvement measure of all work aspects,safe clinical infusion can be provided.

  7. Harvesting geographic features from heterogeneous raster maps

    Science.gov (United States)

    Chiang, Yao-Yi

    2010-11-01

    Raster maps offer a great deal of geospatial information and are easily accessible compared to other geospatial data. However, harvesting geographic features locked in heterogeneous raster maps to obtain the geospatial information is challenging. This is because of the varying image quality of raster maps (e.g., scanned maps with poor image quality and computer-generated maps with good image quality), the overlapping geographic features in maps, and the typical lack of metadata (e.g., map geocoordinates, map source, and original vector data). Previous work on map processing is typically limited to a specific type of map and often relies on intensive manual work. In contrast, this thesis investigates a general approach that does not rely on any prior knowledge and requires minimal user effort to process heterogeneous raster maps. This approach includes automatic and supervised techniques to process raster maps for separating individual layers of geographic features from the maps and recognizing geographic features in the separated layers (i.e., detecting road intersections, generating and vectorizing road geometry, and recognizing text labels). The automatic technique eliminates user intervention by exploiting common map properties of how road lines and text labels are drawn in raster maps. For example, the road lines are elongated linear objects and the characters are small connected-objects. The supervised technique utilizes labels of road and text areas to handle complex raster maps, or maps with poor image quality, and can process a variety of raster maps with minimal user input. The results show that the general approach can handle raster maps with varying map complexity, color usage, and image quality. By matching extracted road intersections to another geospatial dataset, we can identify the geocoordinates of a raster map and further align the raster map, separated feature layers from the map, and recognized features from the layers with the geospatial

  8. EFFECTS OF GREEN MACROALGAE ON CLASSIFICATION OF SEAGRASS IN SIDE SCAN SONAR IMAGERY

    Science.gov (United States)

    High resolution maps of seagrass beds are useful for monitoring estuarine condition, managing fish habitats, and modeling estuarine processes. Side scan sonar (SSS) is one method for producing spatially accurate seagrass maps, although it has not been used widely. Our team rece...

  9. Properties of Calcium Acetate Manufactured with Etching Waste Solution and Limestone Sludge as a Cementitious High-Early-Strength Admixture

    Directory of Open Access Journals (Sweden)

    Deuck-Mo Kim

    2016-01-01

    Full Text Available Concrete is one of the most widely used construction materials. There are several methods available to improve its performance, with one of them being the use of high-early-strength admixtures (HESAs. Typical HESAs include calcium nitrate, calcium chloride, and calcium formate (CF. Industrial by-products, such as acetic acid and lime stone sludge (LSS, can be used together to produce calcium acetate (CA, which can subsequently be used as a cementitious HESA. In this study, calcium carbonate and LSS were mixed with cement in weight ratios of 1 : 1, 1 : 1.5, and 1 : 2, and the properties of the as-produced CA were evaluated. CA and CF were mixed with cement in different weight ratios (0, 1, 2, and 3 wt% to obtain CA- and CF-mortars, respectively. The flow behavior, setting time, pH, and compressive strength of these mortars were evaluated, and their X-ray diffraction patterns were also analyzed. It was found that as the CF content in the CF-mortar increased, the initial strength of the mortar also increased. However, it impaired its long-term strength. On the other hand, when 1% CA was mixed with cement, satisfactory early and long-term strengths were achieved. Thus, CA, which is obtained from industrial by-products, can be an effective HESA.

  10. Corona discharge experiments in admixtures of N2 and CH4: a laboratory simulation of Titan's atmosphere

    International Nuclear Information System (INIS)

    A positive corona discharge fed by a N2 : CH4 mixture (98 : 2) at atmospheric pressure and ambient temperature has been studied as a laboratory mimic of the chemical processes occurring in the atmosphere of Titan, Saturn's largest moon. In situ measurements of UV and IR transmission spectra within the discharge have shown that the main chemical product is C2H2, produced by dissociation of CH4, with small but significant traces of ethane and HCN, all species that have been detected in Titan's atmosphere. A small amount (0.2%) of CH4 was decomposed after 12 min of treatment requiring an average energy of 2.7 kWh g-1. After 14 min the discharge was terminated due to the formation of a solid yellow deposit on the central wire electrode. Such a deposit is similar to that observed in other discharges and is believed to be an analogue of the aerosol and dust observed in Titan's atmosphere and is composed of chemical species commonly known as 'tholins'. We have also explored the electrical properties of the discharge. The admixture of methane into nitrogen caused an increase in the onset voltage of the discharge and consequently led to a reduction in the measured discharge current.

  11. Effect of expansive admixtures on the shrinkage and mechanical properties of high-performance fiber-reinforced cement composites.

    Science.gov (United States)

    Choi, Won-Chang; Yun, Hyun-Do

    2013-01-01

    High-performance fiber-reinforced cement composites (HPFRCCs) are characterized by strain-hardening and multiple cracking during the inelastic deformation process, but they also develop high shrinkage strain. This study investigates the effects of replacing Portland cement with calcium sulfoaluminate-based expansive admixtures (CSA EXAs) to compensate for the shrinkage and associated mechanical behavior of HPFRCCs. Two types of CSA EXA (CSA-K and CSA-J), each with a different chemical composition, are used in this study. Various replacement ratios (0%, 8%, 10%, 12%, and 14% by weight of cement) of CSA EXA are considered for the design of HPFRCC mixtures reinforced with 1.5% polyethylene (PE) fibers by volume. Mechanical properties, such as shrinkage compensation, compressive strength, flexural strength, and direct tensile strength, of the HPFRCC mixtures are examined. Also, crack width and development are investigated to determine the effects of the EXAs on the performance of the HPFRCC mixtures, and a performance index is used to quantify the performance of mixture. The results indicate that replacements of 10% CSA-K (Type 1) and 8% CSA-J (Type 2) considerably enhance the mechanical properties and reduce shrinkage of HPFRCCs. PMID:24376382

  12. Growth, structural, spectral, mechanical, thermal and dielectric characterization of phosphoric acid admixtured L-alanine (PLA) single crystals

    Science.gov (United States)

    Rose, A. S. J. Lucia; Selvarajan, P.; Perumal, S.

    2011-10-01

    Phosphoric acid admixtured L-alanine (PLA) single crystals were grown successfully by solution method with slow evaporation technique at room temperature. Crystals of size 18 mm × 12 mm × 8 mm have been obtained in 28 days. The grown crystals were colorless and transparent. The solubility of the grown samples has been found out at various temperatures. The lattice parameters of the grown crystals were determined by X-ray diffraction technique. The reflection planes of the sample were confirmed by the powder X-ray diffraction study and diffraction peaks were indexed. Fourier transform infrared (FTIR) studies were used to confirm the presence of various functional groups in the crystals. UV-visible transmittance spectrum was recorded to study the optical transparency of grown crystal. The nonlinear optical (NLO) property of the grown crystal was confirmed by Kurtz-Perry powder technique and a study of its second harmonic generation efficiency in comparison with potassium dihydrogen phosphate (KDP) has been made. The mechanical strength of the crystal was estimated by Vickers hardness test. The grown crystals were subjected to thermo gravimetric and differential thermal analysis (TG/DTA). The dielectric behavior of the sample was also studied.

  13. Effect of Expansive Admixtures on the Shrinkage and Mechanical Properties of High-Performance Fiber-Reinforced Cement Composites

    Directory of Open Access Journals (Sweden)

    Won-Chang Choi

    2013-01-01

    Full Text Available High-performance fiber-reinforced cement composites (HPFRCCs are characterized by strain-hardening and multiple cracking during the inelastic deformation process, but they also develop high shrinkage strain. This study investigates the effects of replacing Portland cement with calcium sulfoaluminate-based expansive admixtures (CSA EXAs to compensate for the shrinkage and associated mechanical behavior of HPFRCCs. Two types of CSA EXA (CSA-K and CSA-J, each with a different chemical composition, are used in this study. Various replacement ratios (0%, 8%, 10%, 12%, and 14% by weight of cement of CSA EXA are considered for the design of HPFRCC mixtures reinforced with 1.5% polyethylene (PE fibers by volume. Mechanical properties, such as shrinkage compensation, compressive strength, flexural strength, and direct tensile strength, of the HPFRCC mixtures are examined. Also, crack width and development are investigated to determine the effects of the EXAs on the performance of the HPFRCC mixtures, and a performance index is used to quantify the performance of mixture. The results indicate that replacements of 10% CSA-K (Type 1 and 8% CSA-J (Type 2 considerably enhance the mechanical properties and reduce shrinkage of HPFRCCs.

  14. Influence on the physical-mechanical properties of portland-cement mortar, have admixtures of colophony and tannin

    Directory of Open Access Journals (Sweden)

    Fernández Cánovas, M.

    1989-12-01

    Full Text Available The colophony has been used as an admixture in the Portland cement mortar with the intention to observe its influence on the air content, water absorption, adhesive capacity and mechanical properties. The results obtained have shown that, the colophony acts as air entrainment, reduces the permeability and improves the adhesion between the past and aggregates. Likewise, the addition of tannin and montan wax to the colophony has the efect of reducing the formation of foam and improves the impermeability of the mortar.

    Se ha empleado la colofonia como aditivo en el mortero de cemento portland con el fin de observar su influencia sobre el contenido de aire, absorción de agua, capacidad adhesiva y propiedades mecánicas. Los resultados obtenidos han puesto de manifiesto que la colofonia actúa como aireante, aumenta la impermeabilidad y mejora la adherencia de la pasta al árido. Asimismo, la adición de tanino y cera montana a la colofonia tiene el efecto de reducir la formación de espuma y mejorar también la impermeabilidad del mortero.

  15. Reduced admixture of North Atlantic Deep Water to the deep central South Pacific during the last two glacial periods

    Science.gov (United States)

    Molina-Kescher, Mario; Frank, Martin; Tapia, Raúl; Ronge, Thomas A.; Nürnberg, Dirk; Tiedemann, Ralf

    2016-06-01

    The South Pacific is a sensitive location for the variability of the global oceanic thermohaline circulation given that deep waters from the Atlantic Ocean, the Southern Ocean, and the Pacific Basin are exchanged. Here we reconstruct the deep water circulation of the central South Pacific for the last two glacial cycles (from 240,000 years ago to the Holocene) based on radiogenic neodymium (Nd) and lead (Pb) isotope records complemented by benthic stable carbon data obtained from two sediment cores located on the flanks of the East Pacific Rise. The records show small but consistent glacial/interglacial changes in all three isotopic systems with interglacial average values of -5.8 and 18.757 for ɛNd and 206Pb/204Pb, respectively, whereas glacial averages are -5.3 and 18.744. Comparison of this variability of Circumpolar Deep Water (CDW) to previously published records along the pathway of the global thermohaline circulation is consistent with reduced admixture of North Atlantic Deep Water to CDW during cold stages. The absolute values and amplitudes of the benthic δ13C variations are essentially indistinguishable from other records of the Southern Hemisphere and confirm that the low central South Pacific sedimentation rates did not result in a significant reduction of the amplitude of any of the measured proxies. In addition, the combined detrital Nd and strontium (87Sr/86Sr) isotope signatures imply that Australian and New Zealand dust has remained the principal contributor of lithogenic material to the central South Pacific.

  16. A multicenter study of biological effects assessment of pharmacy workers occupationally exposed to antineoplastic drugs in Pharmacy Intravenous Admixture Services.

    Science.gov (United States)

    Zhang, Jingjing; Bao, Jianan; Wang, Renying; Geng, Zhou; Chen, Yao; Liu, Xinchun; Xie, Yongzhong; Jiang, Ling; Deng, Yufei; Liu, Gaolin; Xu, Rong; Miao, Liyan

    2016-09-01

    This multi-centered study was designed to evaluate the biological effects of exposure to antineoplastic drugs (ADs) at PIVAS (Pharmacy Intravenous Admixture Service) across ten Chinese hospitals. 8-hydroxy-2-deoxyguanosine (8-OHdG) was used as a biomarker of DNA oxidative damage and lymphocyte apoptosis assays using peripheral lymphocyte cells were used to detect primary DNA damage. The mutagenicity activity was estimated with the Ames fluctuation test. 158 exposed and 143 unexposed workers participated in this study. The urinary 8-OHdG/Cr concentrations of the exposed group was 22.05±17.89ng/mg Cr, which was significantly higher than controls of 17.36±13.50ng/mg Cr (P<0.05). The rate of early lymphocyte apoptosis was slightly increased in exposed group than that of the control group (P=0.087). The mutagenic activity was significantly higher in the exposed group relative to the control group (P<0.05). Moreover, while no statistically significant difference was observed, higher concentrations of 8-OHdG/Cr in urine and an early lymphocyte apoptosis rate were found in exposed group II as compared to exposed group I. In addition, a significant correlation between early lymphocyte apoptosis and exposure time to ADs was also observed (P<0.05). In conclusion, our study identified elevated biomarkers in PIVAS workers exposed to ADs. However whether these findings could lead to increased incidence of genotoxic responses remains to be further investigated. PMID:27179702

  17. Re-scan confocal microscopy: scanning twice for better resolution.

    Science.gov (United States)

    De Luca, Giulia M R; Breedijk, Ronald M P; Brandt, Rick A J; Zeelenberg, Christiaan H C; de Jong, Babette E; Timmermans, Wendy; Azar, Leila Nahidi; Hoebe, Ron A; Stallinga, Sjoerd; Manders, Erik M M

    2013-01-01

    We present a new super-resolution technique, Re-scan Confocal Microscopy (RCM), based on standard confocal microscopy extended with an optical (re-scanning) unit that projects the image directly on a CCD-camera. This new microscope has improved lateral resolution and strongly improved sensitivity while maintaining the sectioning capability of a standard confocal microscope. This simple technology is typically useful for biological applications where the combination high-resolution and high-sensitivity is required.

  18. The genetic population structure of northern Sweden and its implications for mapping genetic diseases.

    Science.gov (United States)

    Einarsdottir, Elisabet; Egerbladh, Inez; Beckman, Lars; Holmberg, Dan; Escher, Stefan A

    2007-11-01

    The northern Swedish population has a history of admixture of three ethnic groups and a dramatic population growth from a relatively small founder population. This has resulted in founder effects that together with unique resources for genealogical analyses provide excellent conditions for genetic mapping of monogenic diseases. Several recent examples of successful mapping of genetic factors underlying susceptibility to complex diseases have suggested that the population of northern Sweden may also be an important tool for efficient mapping of more complex phenotypes. A potential factor contributing to these effects may be population sub-isolates within the large river valleys, constituting a central geographic characteristic of this region. We here provide evidence that marriage patterns as well as the distribution of gene frequencies in a set of marker loci are compatible with this notion. The possible implications of this population structure on linkage- and association based strategies for identifying genes contributing risk to complex diseases are discussed.

  19. Scanning microscopic four-point conductivity probes

    DEFF Research Database (Denmark)

    Petersen, Christian Leth; Hansen, Torben Mikael; Bøggild, Peter;

    2002-01-01

    A method for fabricating microscopic four-point probes is presented. The method uses silicon-based microfabrication technology involving only two patterning steps. The last step in the fabrication process is an unmasked deposition of the conducting probe material, and it is thus possible to select...... the conducting material either for a silicon wafer or a single probe unit. Using shadow masking photolithography an electrode spacing (pitch) down to 1.1 mum was obtained, with cantilever separation down to 200 run. Characterisation measurements have shown the microscopic probes to be mechanically very flexible...... and robust. Repeated conductivity measurements on polythiophene films in the same surface area are reproduced within an accuracy of 3%. Automated nanoresolution position control allows scanning across millimetre sized areas, in order to create high spatial resolution maps of the in-plane conductivity....

  20. How to scan polymer gels with MRI?

    Science.gov (United States)

    De Deene, Y.

    2013-06-01

    The absorbed radiation dose fixated in a polymer gel dosimeter can be read out by several methods such as magnetic resonance imaging (MRI), optical CT, X-ray CT and ultrasound with MRI being the first method that was explored. Although MRI was considered as an elegant scanning technique, readily available in most hospitals, it was later found that using a non-optimized imaging protocol may result in unacceptable deviations in the obtained dose distribution. Although most medical physicists have an understanding of the basic principles of magnetic resonance imaging (MRI), the optimization of quantitative imaging sequences and protocols is often perceived as the work of MRI experts. In this paper, we aim at providing the reader with some easy guidelines in how to obtain reliable quantitative MRI maps.