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Sample records for admixture mapping studies

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

    PubMed

    Beleza, Sandra; Campos, Joana; Lopes, Jailson; Araújo, Isabel Inês; Hoppfer Almada, Ana; Correia e Silva, António; Parra, Esteban J; Rocha, Jorge

    2012-01-01

    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 implications for

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

    PubMed Central

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

    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 one second to forced vital capacity, measured by spirometry performed after bronchodilator administration. Global African ancestry inversely associated with FEV1/FVC (p = 0.035). Genome-wide admixture analysis, controlling for age, gender, body mass index, current smoking status, pack-years smoked, and four principal components summarizing the genetic background of African Americans in the COPDGene Study, identified a region on chromosome 12q14.1 associated with FEV1/FVC (p = 2.1 × 10-6) when regressed on local ancestry. Allelic association in this region of chromosome 12 identified an intronic variant in FAM19A2 (rs348644) as associated with FEV1/FVC (p=1.76 × 10-6). By combining admixture and association mapping, a marker on chromosome 12q14.1 was identified as being associated with reduced FEV1/FVC ratio among African-Americans in the COPDGene Study. PMID:25112515

  3. Power comparison of admixture mapping and direct association analysis in genome-wide association studies.

    PubMed

    Qin, Huaizhen; Zhu, Xiaofeng

    2012-04-01

    When dense markers are available, one can interrogate almost every common variant across the genome via imputation and single nucleotide polymorphism (SNP) test, which has become a routine in current genome-wide association studies (GWASs). As a complement, admixture mapping exploits the long-range linkage disequilibrium (LD) generated by admixture between genetically distinct ancestral populations. It is then questionable whether admixture mapping analysis is still necessary in detecting the disease associated variants in admixed populations. We argue that admixture mapping is able to reduce the burden of massive comparisons in GWASs; it therefore can be a powerful tool to locate the disease variants with substantial allele frequency differences between ancestral populations. In this report we studied a two-stage approach, where candidate regions are defined by conducting admixture mapping at stage 1, and single SNP association tests are followed at stage 2 within the candidate regions defined at stage 1. We first established the genome-wide significance levels corresponding to the criteria to define the candidate regions at stage 1 by simulations. We next compared the power of the two-stage approach with direct association analysis. Our simulations suggest that the two-stage approach can be more powerful than the standard genome-wide association analysis when the allele frequency difference of a causal variant in ancestral populations, is larger than 0.4. Our conclusion is consistent with a theoretical prediction by Risch and Tang ([2006] Am J Hum Genet 79:S254). Surprisingly, our study also suggests that power can be improved when we use less strict criteria to define the candidate regions at stage 1.

  4. GWAS and admixture mapping identify different asthma-associated loci in Latinos: The GALA II Study

    PubMed Central

    Galanter, Joshua M; Gignoux, Christopher R; Torgerson, Dara G; Roth, Lindsey A; Eng, Celeste; Oh, Sam S; Nguyen, Elizabeth A; Drake, Katherine A; Huntsman, Scott; Hu, Donglei; Sen, Saunak; Davis, Adam; Farber, Harold J.; Avila, Pedro C.; Brigino-Buenaventura, Emerita; LeNoir, Michael A.; Meade, Kelley; Serebrisky, Denise; Borrell, Luisa N; Rodríguez-Cintrón, William; Estrada, Andres Moreno; Mendoza, Karla Sandoval; Winkler, Cheryl A.; Klitz, William; Romieu, Isabelle; London, Stephanie J.; Gilliland, Frank; Martinez, Fernando; Bustamante, Carlos; Williams, L Keoki; Kumar, Rajesh; Rodríguez-Santana, José R.; Burchard, and Esteban G.

    2013-01-01

    Background Asthma is a complex disease with both genetic and environmental causes. Genome-wide association studies of asthma have mostly involved European populations and replication of positive associations has been inconsistent. Objective To identify asthma-associated genes in a large Latino population with genome-wide association analysis and admixture mapping. Methods Latino children with asthma (n = 1,893) and healthy controls (n = 1,881) were recruited from five sites in the United States: Puerto Rico, New York, Chicago, Houston, and the San Francisco Bay Area. Subjects were genotyped on an Affymetrix World Array IV chip. We performed genome-wide association and admixture mapping to identify asthma-associated loci. Results We identified a significant association between ancestry and asthma at 6p21 (lowest p-value: rs2523924, p < 5 × 10−6). This association replicates in a meta-analysis of the EVE Asthma Consortium (p = 0.01). Fine mapping of the region in this study and the EVE Asthma Consortium suggests an association between PSORS1C1 and asthma. We confirmed the strong allelic association between the 17q21 asthma in Latinos (IKZF3, lowest p-value: rs90792, OR: 0.67, 95% CI 0.61 – 0.75, p = 6 × 10−13) and replicated associations in several genes that had previously been associated with asthma in genome-wide association studies. Conclusions Admixture mapping and genome-wide association are complementary techniques that provide evidence for multiple asthma-associated loci in Latinos. Admixture mapping identifies a novel locus on 6p21 that replicates in a meta-analysis of several Latino populations, while genome-wide association confirms the previously identified locus on 17q21. PMID:24406073

  5. Results from a prostate cancer admixture mapping study in African-American men.

    PubMed

    Bock, Cathryn Hufford; Schwartz, Ann G; Ruterbusch, Julie J; Levin, Albert M; Neslund-Dudas, Christine; Land, Susan J; Wenzlaff, Angela S; Reich, David; McKeigue, Paul; Chen, Wei; Heath, Elisabeth I; Powell, Isaac J; Kittles, Rick A; Rybicki, Benjamin A

    2009-11-01

    There are considerable racial disparities in prostate cancer risk, with a 60% higher incidence rate among African-American (AA) men compared with European-American (EA) men, and a 2.4-fold higher mortality rate in AA men than in EA men. Recently, studies have implicated several African-ancestry associated prostate cancer susceptibility loci on chromosome 8q24. In the current study, we performed admixture mapping in AA men from two independent case-control studies of prostate cancer to confirm the 8q24 ancestry association and also identify other genomic regions that may harbor prostate cancer susceptibility genes. A total of 482 cases and 261 controls were genotyped for 1,509 ancestry informative markers across the genome. The mean estimated individual admixture proportions were 20% European and 80% African. The most significant observed increase in European ancestry occurred at rs2141360 on chromosome 7q31 in both the case-only (P = 0.0000035) and case-control analyses. The most significant observed increase in African ancestry across the genome occurred at a locus on chromosome 5q35 identified by SNPs rs7729084 (case-only analysis P = 0.002), and rs12474977 (case-control analysis P = 0.004), which are separated by 646 kb and were adjacent to one another on the panel. On chromosome 8, rs4367565 was associated with the greatest excess African ancestry in both the case-only and case-control analyses (case-only and case-control P = 0.02), confirming previously reported African-ancestry associations with chromosome 8q24. In conclusion, we confirmed ancestry associations on 8q24, and identified additional ancestry-associated regions potentially harboring prostate cancer susceptibility loci.

  6. Admixture in Mexico City: implications for admixture mapping of type 2 diabetes genetic risk factors.

    PubMed

    Martinez-Marignac, Veronica L; Valladares, Adan; Cameron, Emily; Chan, Andrea; Perera, Arjuna; Globus-Goldberg, Rachel; Wacher, Niels; Kumate, Jesús; McKeigue, Paul; O'Donnell, David; Shriver, Mark D; Cruz, Miguel; Parra, Esteban J

    2007-02-01

    Admixture mapping is a recently developed method for identifying genetic risk factors involved in complex traits or diseases showing prevalence differences between major continental groups. Type 2 diabetes (T2D) is at least twice as prevalent in Native American populations as in populations of European ancestry, so admixture mapping is well suited to study the genetic basis of this complex disease. We have characterized the admixture proportions in a sample of 286 unrelated T2D patients and 275 controls from Mexico City and we discuss the implications of the results for admixture mapping studies. Admixture proportions were estimated using 69 autosomal ancestry-informative markers (AIMs). Maternal and paternal contributions were estimated from geographically informative mtDNA and Y-specific polymorphisms. The average proportions of Native American, European and, West African admixture were estimated as 65, 30, and 5%, respectively. The contributions of Native American ancestors to maternal and paternal lineages were estimated as 90 and 40%, respectively. In a logistic model with higher educational status as dependent variable, the odds ratio for higher educational status associated with an increase from 0 to 1 in European admixture proportions was 9.4 (95%, credible interval 3.8-22.6). This association of socioeconomic status with individual admixture proportion shows that genetic stratification in this population is paralleled, and possibly maintained, by socioeconomic stratification. The effective number of generations back to unadmixed ancestors was 6.7 (95% CI 5.7-8.0), from which we can estimate that genome-wide admixture mapping will require typing about 1,400 evenly distributed AIMs to localize genes underlying disease risk between populations of European and Native American ancestry. Sample sizes of about 2,000 cases will be required to detect any locus that contributes an ancestry risk ratio of at least 1.5.

  7. A Genomewide Admixture Map for Latino Populations

    PubMed Central

    Price, Alkes L. ; Patterson, Nick ; Yu, Fuli ; Cox, David R. ; Waliszewska, Alicja ; McDonald, Gavin J. ; Tandon, Arti ; Schirmer, Christine ; Neubauer, Julie ; Bedoya, Gabriel ; Duque, Constanza ; Villegas, Alberto ; Bortolini, Maria Catira ; Salzano, Francisco M. ; Gallo, Carla ; Mazzotti, Guido ; Tello-Ruiz, Marcela ; Riba, Laura ; Aguilar-Salinas, Carlos A. ; Canizales-Quinteros, Samuel ; Menjivar, Marta ; Klitz, William ; Henderson, Brian ; Haiman, Christopher A. ; Winkler, Cheryl ; Tusie-Luna, Teresa ; Ruiz-Linares, Andrés ; Reich, David 

    2007-01-01

    Admixture mapping is an economical and powerful approach for localizing disease genes in populations of recently mixed ancestry and has proven successful in African Americans. The method holds equal promise for Latinos, who typically inherit a mix of European, Native American, and African ancestry. However, admixture mapping in Latinos has not been practical because of the lack of a map of ancestry-informative markers validated in Native American and other populations. To address this, we screened multiple databases, containing millions of markers, to identify 4,186 markers that were putatively informative for determining the ancestry of chromosomal segments in Latino populations. We experimentally validated each of these markers in at least 232 new Latino, European, Native American, and African samples, and we selected a subset of 1,649 markers to form an admixture map. An advantage of our strategy is that we focused our map on markers distinguishing Native American from other ancestries and restricted it to markers with very similar frequencies in Europeans and Africans, which decreased the number of markers needed and minimized the possibility of false disease associations. We evaluated the effectiveness of our map for localizing disease genes in four Latino populations from both North and South America. PMID:17503322

  8. Admixture in Hispanic Americans: its impact on ITGAM association and implications for admixture mapping in SLE.

    PubMed

    Molineros, J E; Kim-Howard, X; Deshmukh, H; Jacob, C O; Harley, J B; Nath, S K

    2009-07-01

    Systemic Lupus Erythematosus (SLE) disproportionately affects minorities, such as Hispanic Americans (HA). Prevalence of SLE is 3-5 times higher in HA than in European-derived populations and have more active disease at the time of diagnosis, with more serious organ system involvement. HA is an admixed population, it is possible that there is an effect of admixture on the relative risk of the disease. This admixture can create substantial increase of linkage disequilibrium (LD) in both magnitude and range, which can provide a unique opportunity for admixture mapping. The main objectives of this study are to (a) estimate hidden population structure in HA individuals; (b) estimate individual ancestry proportions and its impact on SLE risk; (c) assess impact of admixture on ITGAM association, a recently identified SLE susceptibility gene; and (d) estimate power of admixture mapping in HA. Our dataset contained 1125 individuals, of whom 884 (657 SLE cases and 227 controls) were self-classified as HA. Using 107 unlinked ancestry informative markers (AIMs), we estimated hidden population structure and individual ancestry in HA. Out of 5671 possible pairwise LD, 54% were statistically significant, indicating recent population admixture. The best-fitted model for HA was a four-population model with average ancestry of European (48%), American-Indian (AI) (40%), African (8%) and a fourth population (4%) with unknown ancestry. We also identified significant higher risk associated with AI ancestry (odds ratio (OR)=4.84, P=0.0001, 95% CI (confidence interval)=2.14-10.95) on overall SLE. We showed that ITGAM is associated as a risk factor for SLE (OR=2.06, P=8.74 x 10(-5), 95% CI=1.44-2.97). This association is not affected by population substructure or admixture. We have shown that HA have great potential and are an appropriate population for admixture mapping. As expected, the case-only design is more powerful than case-control design, for any given admixture proportion or

  9. Methods for High-Density Admixture Mapping of Disease Genes

    PubMed Central

    Patterson, Nick; Hattangadi, Neil; Lane, Barton; Lohmueller, Kirk E.; Hafler, David A.; Oksenberg, Jorge R.; Hauser, Stephen L.; Smith, Michael W.; O’Brien, Stephen J.; Altshuler, David; Daly, Mark J.; Reich, David

    2004-01-01

    Admixture mapping (also known as “mapping by admixture linkage disequilibrium,” or MALD) has been proposed as an efficient approach to localizing disease-causing variants that differ in frequency (because of either drift or selection) between two historically separated populations. Near a disease gene, patient populations descended from the recent mixing of two or more ethnic groups should have an increased probability of inheriting the alleles derived from the ethnic group that carries more disease-susceptibility alleles. The central attraction of admixture mapping is that, since gene flow has occurred recently in modern populations (e.g., in African and Hispanic Americans in the past 20 generations), it is expected that admixture-generated linkage disequilibrium should extend for many centimorgans. High-resolution marker sets are now becoming available to test this approach, but progress will require (a) computational methods to infer ancestral origin at each point in the genome and (b) empirical characterization of the general properties of linkage disequilibrium due to admixture. Here we describe statistical methods to estimate the ancestral origin of a locus on the basis of the composite genotypes of linked markers, and we show that this approach accurately estimates states of ancestral origin along the genome. We apply this approach to show that strong admixture linkage disequilibrium extends, on average, for 17 cM in African Americans. Finally, we present power calculations under varying models of disease risk, sample size, and proportions of ancestry. Studying ∼2,500 markers in ∼2,500 patients should provide power to detect many regions contributing to common disease. A particularly important result is that the power of an admixture mapping study to detect a locus will be nearly the same for a wide range of mixture scenarios: the mixture proportion should be 10%–90% from both ancestral populations. PMID:15088269

  10. Genome-wide Association Study and Admixture Mapping Reveal New Loci Associated with Total IgE Levels in Latinos

    PubMed Central

    Pino-Yanes, Maria; Gignoux, Christopher R.; Galanter, Joshua M.; Levin, Albert M.; Campbell, Catarina D.; Eng, Celeste; Huntsman, Scott; Nishimura, Katherine K.; Gourraud, Pierre-Antoine; Mohajeri, Kiana; O'Roak, Brian J.; Hu, Donglei; Mathias, Rasika A.; Nguyen, Elizabeth A.; Roth, Lindsey A.; Padhukasahasram, Badri; Moreno-Estrada, Andres; Sandoval, Karla; Winkler, Cheryl A.; Lurmann, Fred; Davis, Adam; Farber, Harold J.; Meade, Kelley; Avila, Pedro C.; Serebrisky, Denise; Chapela, Rocio; Ford, Jean G.; Lenoir, Michael A.; Thyne, Shannon M.; Brigino-Buenaventura, Emerita; Borrell, Luisa N.; Rodriguez-Cintron, William; Sen, Saunak; Kumar, Rajesh; Rodriguez-Santana, Jose R.; Bustamante, Carlos D.; Martinez, Fernando D.; Raby, Benjamin A.; Weiss, Scott T.; Nicolae, Dan L.; Ober, Carole; Meyers, Deborah A.; Bleecker, Eugene R.; Mack, Steven J.; Hernandez, Ryan D.; Eichler, Evan E.; Barnes, Kathleen C.; Williams, L. Keoki; Torgerson, Dara G.; Burchard, Esteban G.

    2014-01-01

    Background Immunoglobulin E (IgE) is a key mediator of allergic inflammation and is frequently elevated in allergic disorders. Objective To identify genetic variants associated with IgE levels in Latinos. Methods We performed a genome-wide association study (GWAS) and admixture mapping of total IgE levels in 3,334 Latinos from the Genes-environments & Admixture in Latino Americans (GALA II) study. Replication was evaluated in 454 Latinos, 1,564 European Americans, and 3,187 African Americans from independent studies. Results We confirmed associations of six genes identified by previous GWAS and identified a novel genome-wide significant association of a polymorphism in ZNF365 with total IgE (rs200076616, p=2.3x10−8). We next identified four admixture mapping peaks (6p21.32-p22.1, 13p22-31, 14q23.2, and 22q13.1) where local African, European, and/or Native American ancestry was significantly associated with IgE levels. The most significant peak was 6p21.32-p22.1, where Native American ancestry was associated with lower levels of IgE (p=4.95x10−8). All but 22q13.1 were replicated in an independent sample of Latinos, and two of the peaks were replicated in African Americans (6p21.32-p22.1 and 14q23.2). Fine mapping of 6p21.32-p22.1 identified six genome-wide significant single nucleotide polymorphisms in Latinos, two of which replicated in European Americans. Another SNP was peak-wide significant within 14q23.2 in African Americans (rs1741099, p=3.7x10−6), and replicated in non-African American samples (p=0.011). Conclusion We confirmed genetic associations at six genes, and identified novel associations within ZNF365, HLA-DQA1, and 14q23.2. Our results highlight the importance of studying diverse, multi-ethnic populations to uncover novel loci associated with total IgE levels. PMID:25488688

  11. Extending Admixture Mapping to Nuclear Pedigrees: Application to Sarcoidosis

    PubMed Central

    McKeigue, Paul M.; Colombo, Marco; Agakov, Felix; Datta, Indrani; Levin, Albert; Favro, David; Gray-Montgomery, Courtney; Iannuzzi, Michael C.; Rybicki, Benjamin A.

    2013-01-01

    We describe statistical methods that extend the application of admixture mapping from unrelated individuals to nuclear pedigrees, allowing existing pedigree-based collections to be fully exploited. Computational challenges have been overcome by developing a fast algorithm that exploits the factorial structure of the underlying model of ancestry transitions. This has been implemented as an extension of the program ADMIXMAP. We demonstrate the application of the method to a study of sarcoidosis in African Americans that has previously been analyzed only as an admixture mapping study restricted to unrelated individuals. Although the ancestry signals detected in this pedigree analysis are generally similar to those detected in the earlier analysis of unrelated cases, we are able to extract more information and this yields a much sharper exclusion map; using the classical criterion of an LOD score of minus 2, the pedigree analysis is able to exclude a risk ratio of 2 or more associated with African ancestry over 96% of the genome, compared with only 83% in the earlier analysis of unrelated individuals only. Although the pedigree extension of ADMIXMAP can use ancestry-informative markers only at relatively low density, it can use imputed ancestry states from programs such as WINPOP or HAPMIX that use dense SNP marker genotypes for admixture mapping. This extends both the efficiency and the range of application of this powerful gene mapping method. PMID:23371909

  12. Admixture mapping scans identify a locus affecting retinal vascular caliber in hypertensive African Americans: the Atherosclerosis Risk in Communities (ARIC) study.

    PubMed

    Cheng, Ching-Yu; Reich, David; Wong, Tien Y; Klein, Ronald; Klein, Barbara E K; Patterson, Nick; Tandon, Arti; Li, Man; Boerwinkle, Eric; Sharrett, A Richey; Kao, W H Linda

    2010-04-15

    Retinal vascular caliber provides information about the structure and health of the microvascular system and is associated with cardiovascular and cerebrovascular diseases. Compared to European Americans, African Americans tend to have wider retinal arteriolar and venular caliber, even after controlling for cardiovascular risk factors. This has suggested the hypothesis that differences in genetic background may contribute to racial/ethnic differences in retinal vascular caliber. Using 1,365 ancestry-informative SNPs, we estimated the percentage of African ancestry (PAA) and conducted genome-wide admixture mapping scans in 1,737 African Americans from the Atherosclerosis Risk in Communities (ARIC) study. Central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE) representing summary measures of retinal arteriolar and venular caliber, respectively, were measured from retinal photographs. PAA was significantly correlated with CRVE (rho = 0.071, P = 0.003), but not CRAE (rho = 0.032, P = 0.182). Using admixture mapping, we did not detect significant admixture association with either CRAE (genome-wide score = -0.73) or CRVE (genome-wide score = -0.69). An a priori subgroup analysis among hypertensive individuals detected a genome-wide significant association of CRVE with greater African ancestry at chromosome 6p21.1 (genome-wide score = 2.31, locus-specific LOD = 5.47). Each additional copy of an African ancestral allele at the 6p21.1 peak was associated with an average increase in CRVE of 6.14 microm in the hypertensives, but had no significant effects in the non-hypertensives (P for heterogeneity <0.001). Further mapping in the 6p21.1 region may uncover novel genetic variants affecting retinal vascular caliber and further insights into the interaction between genetic effects of the microvascular system and hypertension.

  13. Admixture mapping of lung cancer in 1812 African-Americans.

    PubMed

    Schwartz, Ann G; Wenzlaff, Angela S; Bock, Cathryn H; Ruterbusch, Julie J; Chen, Wei; Cote, Michele L; Artis, Amanda S; Van Dyke, Alison L; Land, Susan J; Harris, Curtis C; Pine, Sharon R; Spitz, Margaret R; Amos, Christopher I; Levin, Albert M; McKeigue, Paul M

    2011-03-01

    Lung cancer continues to be the leading cause of cancer death in the USA and the best example of a cancer with undisputed evidence of environmental risk. However, a genetic contribution to lung cancer has also been demonstrated by studies of familial aggregation, family-based linkage, candidate gene studies and most recently genome-wide association studies (GWAS). The African-American population has been underrepresented in these genetic studies and has patterns of cigarette use and linkage disequilibrium that differ from patterns in other populations. Therefore, studies in African-Americans can provide complementary data to localize lung cancer susceptibility genes and explore smoking dependence-related genes. We used admixture mapping to further characterize genetic risk of lung cancer in a series of 837 African-American lung cancer cases and 975 African-American controls genotyped at 1344 ancestry informative single-nucleotide polymorphisms. Both case-only and case-control analyses were conducted using ADMIXMAP adjusted for age, sex, pack-years of smoking, family history of lung cancer, history of emphysema and study site. In case-only analyses, excess European ancestry was observed over a wide region on chromosome 1 with the largest excess seen at rs6587361 for non-small-cell lung cancer (NSCLC) (Z-score = -4.33; P = 1.5 × 10⁻⁵) and for women with NSCLC (Z-score = -4.82; P = 1.4 × 10⁻⁶). Excess African ancestry was also observed on chromosome 3q with a peak Z-score of 3.33 (P = 0.0009) at rs181696 among ever smokers with NSCLC. These results add to the findings from the GWAS in Caucasian populations and suggest novel regions of interest.

  14. Admixture mapping of genetic variants for uterine fibroids

    PubMed Central

    Zhang, Kui; Wiener, Howard; Aissani, Brahim

    2015-01-01

    Uterine leiomyoma (UL) are benign neoplasms arising from the smooth muscle cells of the uterus. One of the established risk factors for UL is African American ethnicity. Studies have consistently shown that African Americans have 2-3 times higher risk compared with that of non-Hispanic Whites. However, there is still no adequate explanation for the higher risk among African Americans. To investigate the genetic contribution to the observed difference between the African American and European American populations, we conducted an admixture scan in 525 eligible African American women participants to the NIEHS uterine fibroid study (NIEHS-UFS). In models with no stratification, we found multiple genomic regions showing significant and suggestive evidence of association, with chromosomal band 2q32.2 at rs256552 showing the highest score (Z-score = 7.86, Bonferroni adjusted p-value = 5.5×10-12) consistent with the suggestive evidence reported for this genomic region in the Black Women's Health Study. However, in models stratified by the body mass index (BMI) covariate, chromosomal 1q42.2 was the sole genomic region that consistently showed suggestive associations across the BMI categories tested (Z-scores ≤ -3.96, Bonferroni adjusted p-values ≤ 0.107). In age-stratified models, a significant association was observed in the older category (age > 40) reaching a Z-score of 6.44 (Bonferroni-adjusted p-value = 1.64 × 10-7) at rs256552. The mean percentage of European ancestry among cases was lower than that among controls in the NIEHS-UFS study. However, our study did not show a significant association between mean percentage of European ancestry and UL. PMID:26040208

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

    PubMed

    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.

  16. Variants for HDL-C, LDL-C and Triglycerides Identified from Admixture Mapping and Fine-Mapping Analysis in African-American Families

    PubMed Central

    Shetty, Priya B.; Tang, Hua; Feng, Tao; Tayo, Bamidele; Morrison, Alanna C.; Kardia, Sharon L.R.; Hanis, Craig L.; Arnett, Donna K.; Hunt, Steven C.; Boerwinkle, Eric; Rao, D.C.; Cooper, R.S.; Risch, Neil; Zhu, Xiaofeng

    2015-01-01

    Background Admixture mapping of lipids was followed-up by family-based association analysis to identify variants for cardiovascular disease in African-Americans. Methods and Results The present study conducted admixture mapping analysis for total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglycerides. The analysis was performed in 1,905 unrelated African-American subjects from the National Heart, Lung and Blood Institute’s Family Blood Pressure Program. Regions showing admixture evidence were followed-up with family-based association analysis in 3,556 African-American subjects from the FBPP. The admixture mapping and family-based association analyses were adjusted for age, age2, sex, body-mass-index, and genome-wide mean ancestry to minimize the confounding due to population stratification. Regions that were suggestive of local ancestry association evidence were found on chromosomes 7 (LDL-C), 8 (HDL-C), 14 (triglycerides) and 19 (total cholesterol and triglycerides). In the fine-mapping analysis, 52,939 SNPs were tested and 11 SNPs (8 independent SNPs) showed nominal significant association with HDL-C (2 SNPs), LDL-C (4 SNPs) and triglycerides (5 SNPs). The family data was used in the fine-mapping to identify SNPs that showed novel associations with lipids and regions including genes with known associations for cardiovascular disease. Conclusions This study identified regions on chromosomes 7, 8, 14 and 19 and 11 SNPs from the fine-mapping analysis that were associated with HDL-C, LDL-C and triglycerides for further studies of cardiovascular disease in African-Americans. PMID:25552592

  17. Mapping by admixture linkage disequilibrium in human populations: Limits and guidelines

    SciTech Connect

    Stephens, J.C.; Briscoe, D.; O`Brien, S.J.

    1994-10-01

    Certain human hereditary conditions, notably those with low penetrance and those which require an environmental event such as infectious disease exposure, are difficult to localize in pedigree analysis, because of uncertainty in the phenotype of an affected patient`s relatives. An approach to locating these genes in human cohort studies would be to use association analysis, which depends on linkage disequilibrium of flanking polymorphic DNA markers. In theory, a high degree of linkage disequilibrium between genes separated by 10-20 cM will be generated and persist in populations that have a history of recent (3-20 generations ago) admixture between genetically differentiated racial groups, such as has occurred in African Americans and Hispanic populations. We have conducted analytic and computer simulations to quantify the effect of genetic, genomic, and population parameters that affect the amount and ascertainment of linkage disequilibrium in populations with a history of genetic admixture. Our goal is to thoroughly explore the ranges of all relevant parameters or factors (e.g., sample size and degree of genetic differentiation between populations) that may be involved in gene localization studies, in hopes of prescribing guidelines for an efficient mapping strategy. The results provide reasonable limits on sample size (200-300 patients), marker number (200-300 in 20-cM intervals), and allele differentiation (loci with allele frequency difference of {ge}.3 between admixed parent populations) to produce an efficient approach (>95% ascertainment) for locating genes not easily tracked in human pedigrees. 321 refs., 8 figs., 7 tabs.

  18. Admixture Mapping of African–American Women in the AMBER Consortium Identifies New Loci for Breast Cancer and Estrogen-Receptor Subtypes

    PubMed Central

    Ruiz-Narváez, Edward A.; Sucheston-Campbell, Lara; Bensen, Jeannette T.; Yao, Song; Haddad, Stephen; Haiman, Christopher A.; Bandera, Elisa V.; John, Esther M.; Bernstein, Leslie; Hu, Jennifer J.; Ziegler, Regina G.; Deming, Sandra L.; Olshan, Andrew F.; Ambrosone, Christine B.; Palmer, Julie R.; Lunetta, Kathryn L.

    2016-01-01

    Recent genetic admixture coupled with striking differences in incidence of estrogen receptor (ER) breast cancer subtypes, as well as severity, between women of African and European ancestry, provides an excellent rationale for performing admixture mapping in African American women with breast cancer risk. We performed the largest breast cancer admixture mapping study with in African American women to identify novel genomic regions associated with the disease. We conducted a genome-wide admixture scan using 2,624 autosomal ancestry informative markers (AIMs) in 3,629 breast cancer cases (including 1,968 ER-positive, 1093 ER-negative, and 601 triple-negative) and 4,658 controls from the African American Breast Cancer Epidemiology and Risk (AMBER) Consortium, a collaborative study of four large geographically different epidemiological studies of breast cancer in African American women. We used an independent case-control study to test for SNP association in regions with genome-wide significant admixture signals. We found two novel genome-wide significant regions of excess African ancestry, 4p16.1 and 17q25.1, associated with ER-positive breast cancer. Two regions known to harbor breast cancer variants, 10q26 and 11q13, were also identified with excess of African ancestry. Fine-mapping of the identified genome-wide significant regions suggests the presence of significant genetic associations with ER-positive breast cancer in 4p16.1 and 11q13. In summary, we identified three novel genomic regions associated with breast cancer risk by ER status, suggesting that additional previously unidentified variants may contribute to the racial differences in breast cancer risk in the African American population. PMID:27708667

  19. Gender and population history: sex bias revealed by studying genetic admixture of Ngazidja population (Comoro Archipelago).

    PubMed

    Gourjon, Géraud; Boëtsch, Gilles; Degioanni, Anna

    2011-04-01

    The peopling of Comoro Archipelago is defined by successive waves of migration from three main areas: the East African Coast (Bantu-speaking populations), the Persia and Arabian Peninsula, and Southeast Asia (especially Indonesia). It follows an apparent classic trihybrid admixture model. To better understand the Comorian population admixture dynamics, we analyzed the contributions of these three historical parental components to its genetic pool. To enhance accuracy and reliability, we used both classical and molecular markers. Samples consist of published data: blood group frequencies, 14 KIR genes, 19 mitochondrial DNA SNPs (to highlight female migrations), 14 Y chromosome SNPs (male migrations). We revealed distinct admixture patterns for autosomal and uniparental markers. KIR gene frequencies had never been used to estimate admixture rates, this being a first assessment of their informative power in admixture studies. To avoid major methodological and statistical bias, we determined admixture coefficients through nine well-tried estimators and their associated software programs (ADMIX95, ADMIX, admix 2.0, LEA, LEADMIX, and Mistura). Results from mtDNA and Y chromosome markers point to an important sex-bias in the admixture event. The original Bantu gene pool received a predominant male-mediated contribution from the Arabian Peninsula and Persia, and a female-mediated contribution from Southeast Asia. Admixture rates estimated from autosomal KIR gene markers point also to an unexpected elevated Austronesian contribution.

  20. Intrahepatic Cholestasis of Pregnancy (ICP) in U.S. Latinas and Chileans: Clinical features, Ancestry Analysis, and Admixture Mapping.

    PubMed

    Bull, Laura N; Hu, Donglei; Shah, Sohela; Temple, Luisa; Silva, Karla; Huntsman, Scott; Melgar, Jennifer; Geiser, Mary T; Sanford, Ukina; Ortiz, Juan A; Lee, Richard H; Kusanovic, Juan P; Ziv, Elad; Vargas, Juan E

    2015-01-01

    In the Americas, women with Indigenous American ancestry are at increased risk of intrahepatic cholestasis of pregnancy (ICP), relative to women of other ethnicities. We hypothesized that ancestry-related genetic factors contribute to this increased risk. We collected clinical and laboratory data, and performed biochemical assays on samples from U.S. Latinas and Chilean women, with and without ICP. The study sample included 198 women with ICP (90 from California, U.S., and 108 from Chile) and 174 pregnant control women (69 from California, U.S., and 105 from Chile). SNP genotyping was performed using Affymetrix arrays. We compared overall genetic ancestry between cases and controls, and used a genome-wide admixture mapping approach to screen for ICP susceptibility loci. We identified commonalities and differences in features of ICP between the 2 countries and determined that cases had a greater proportion of Indigenous American ancestry than did controls (p = 0.034). We performed admixture mapping, taking country of origin into account, and identified one locus for which Native American ancestry was associated with increased risk of ICP at a genome-wide level of significance (P = 3.1 x 10(-5), Pcorrected = 0.035). This locus has an odds ratio of 4.48 (95% CI: 2.21-9.06) for 2 versus zero Indigenous American chromosomes. This locus lies on chromosome 2, with a 10 Mb 95% confidence interval which does not contain any previously identified hereditary 'cholestasis genes.' Our results indicate that genetic factors contribute to the risk of developing ICP in the Americas, and support the utility of clinical and genetic studies of ethnically mixed populations for increasing our understanding of ICP.

  1. Experimental study on durability improvement of fly ash concrete with durability improving admixture.

    PubMed

    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, the compressive strength of fly ash concrete can be improved by 10%-20%, and the drying shrinkage is reduced by 60%. Carbonation resistance of concrete is roughly proportional to water-cement ratio regardless of water-binder ratio and fly ash replacement ratio. For the specimens cured in air for 2 weeks, the freezing-thawing resistance is improved. In addition, by making use of durability improving admixture, it is easier to control the air content and make fly ash concrete into nonair-entraining one. The quality of fly ash concrete is thereby optimized.

  2. Admixture mapping identifies a locus on 6q25 associated with breast cancer risk in US Latinas

    PubMed Central

    Fejerman, Laura; Chen, Gary K.; Eng, Celeste; Huntsman, Scott; Hu, Donglei; Williams, Amy; Pasaniuc, Bogdan; John, Esther M.; Via, Marc; Gignoux, Christopher; Ingles, Sue; Monroe, Kristine R.; Kolonel, Laurence N.; Torres-Mejía, Gabriela; Pérez-Stable, Eliseo J.; González Burchard, Esteban; Henderson, Brian E.; Haiman, Christopher A.; Ziv, Elad

    2012-01-01

    Among US Latinas and Mexican women, those with higher European ancestry have increased risk of breast cancer. We combined an admixture mapping and genome-wide association mapping approach to search for genomic regions that may explain this observation. Latina women with breast cancer (n= 1497) and Latina controls (n= 1272) were genotyped using Affymetrix and Illumina arrays. We inferred locus-specific genetic ancestry and compared the ancestry between cases and controls. We also performed single nucleotide polymorphism (SNP) association analyses in regions of interest. Correction for multiple-hypothesis testing was conducted using permutations (Pcorrected). We identified one region where genetic ancestry was significantly associated with breast cancer risk: 6q25 [odds ratio (OR) per Indigenous American chromosome 0.75, 95% confidence interval (CI): 0.65–0.85, P= 1.1 × 10−5, Pcorrected= 0.02]. A second region on 11p15 showed a trend towards association (OR per Indigenous American chromosome 0.77, 95% CI: 0.68–0.87, P= 4.3 × 10−5, Pcorrected= 0.08). In both regions, breast cancer risk decreased with higher Indigenous American ancestry in concordance with observations made on global ancestry. The peak of the 6q25 signal includes the estrogen receptor 1 (ESR1) gene and 5′ region, a locus previously implicated in breast cancer. Genome-wide association analysis found that a multi-SNP model explained the admixture signal in both regions. Our results confirm that the association between genetic ancestry and breast cancer risk in US Latinas is partly due to genetic differences between populations of European and Indigenous Americans origin. Fine-mapping within the 6q25 and possibly the 11p15 loci will lead to the discovery of the biologically functional variant/s behind this association. PMID:22228098

  3. Distinguishing Recent Admixture from Ancestral Population Structure

    PubMed Central

    Slatkin, Montgomery

    2017-01-01

    We develop and test two methods for distinguishing between recent admixture and ancestral population structure as explanations for greater similarity of one of two populations to an outgroup population. This problem arose when Neanderthals were found to be slightly more similar to nonAfrican than to African populations. The excess similarity is consistent with both recent admixture from Neanderthals into the ancestors of nonAfricans and subdivision in the ancestral population. Although later studies showed that there had been recent admixture, distinguishing between these two classes of models will be important in other situations, particularly when high-coverage genomes cannot be obtained for all populations. One of our two methods is based on the properties of the doubly conditioned frequency spectrum combined with the unconditional frequency spectrum. This method does not require a linkage map and can be used when there is relatively low coverage. The second method uses the extent of linkage disequilibrium among closely linked markers. PMID:28186554

  4. CYP2C9 and VKORC1 Genotypes in Puerto Ricans: A Case for Admixture-Matching in Clinical Pharmacogenetic Studies

    PubMed Central

    Villagra, David; Duconge, Jorge; Windemuth, Andreas; Cadilla, Carmen L; Kocherla, Mohan; Gorowski, Krystyna; Bogaard, Kali; Renta, Jessica Y; Cruz, Irelys A; Mirabal, Sara; Seip, Richard L; Ruaño, Gualberto

    2010-01-01

    Backgrounds Admixture is of great relevance to the clinical application of pharmacogenetics and personalized medicine, but unfortunately these studies have been scarce in Puerto Ricans. Besides, allele frequencies for clinically relevant genetic markers in warfarin response (i.e., CYP2C9 and VKORC1) have not yet been fully characterized in this population. Accordingly, this study is aimed at investigating whether a correlation between overall genetic similarity and CYP2C9 and/or VKORC1 genotypes could be established. Methods 98 DNA samples from Puerto Ricans were genotyped for major CYP2C9 and VKORC1 polymorphisms and tested on a physiogenomic (PG)-array to infer population structure and admixture pattern. Results Analysis affirmed that Puerto Ricans are broadly admixed. A genetic distance dendrogram was constructed by clustering those subjects with similar genetic profiles. Individual VKORC1 and CYP2C9 genotypes were visually overlaid atop the three dendrogram sectors. Sector-1, representing Amerindian ancestry, showed higher VKORC1-1639G>A variant frequency than the rest of the population (p=0.051). Although CYP2C9*3 allele frequencies matched the expected HapMap values, admixture may explain deviations from published findings regarding VKORC1-1639G>A and CYP2C9*2 allele frequencies in sector-3. Conclusions Results suggest that the observed inter-individual variations in ancestral contributions have significant implications for the way each Puerto Rican responds to warfarin therapy. Our findings provide valuable evidence on the importance of controlling for admixture in pharmacogenetic studies of Puerto Rican Hispanics. PMID:20488169

  5. Modeling Continuous Admixture Using Admixture-Induced Linkage Disequilibrium.

    PubMed

    Zhou, Ying; Qiu, Hongxiang; Xu, Shuhua

    2017-02-23

    Recent migrations and inter-ethnic mating of long isolated populations have resulted in genetically admixed populations. To understand the complex population admixture process, which is critical to both evolutionary and medical studies, here we used admixture induced linkage disequilibrium (LD) to infer continuous admixture events, which is common for most existing admixed populations. Unlike previous studies, we expanded the typical continuous admixture model to a more general scenario with isolation after a certain duration of continuous gene flow. Based on the new models, we developed a method, CAMer, to infer the admixture history considering continuous and complex demographic process of gene flow between populations. We evaluated the performance of CAMer by computer simulation and further applied our method to real data analysis of a few well-known admixed populations.

  6. Modeling Continuous Admixture Using Admixture-Induced Linkage Disequilibrium

    PubMed Central

    Zhou, Ying; Qiu, Hongxiang; Xu, Shuhua

    2017-01-01

    Recent migrations and inter-ethnic mating of long isolated populations have resulted in genetically admixed populations. To understand the complex population admixture process, which is critical to both evolutionary and medical studies, here we used admixture induced linkage disequilibrium (LD) to infer continuous admixture events, which is common for most existing admixed populations. Unlike previous studies, we expanded the typical continuous admixture model to a more general scenario with isolation after a certain duration of continuous gene flow. Based on the new models, we developed a method, CAMer, to infer the admixture history considering continuous and complex demographic process of gene flow between populations. We evaluated the performance of CAMer by computer simulation and further applied our method to real data analysis of a few well-known admixed populations. PMID:28230170

  7. Use of admixture and association for detection of quantitative trait loci in the Type 2 Diabetes Genetic Exploration by Next-Generation Sequencing in Ethnic Samples (T2D-GENES) study

    PubMed Central

    2014-01-01

    Admixture mapping and association testing have been successfully applied to the detection of genes for complex diseases. Methods have also been developed to combine these approaches. As an initial step to determine the feasibility of combining admixture and association mapping in the context of whole genome sequencing, we have applied several methods to data from the Genetic Analysis Workshop 18. Here, we describe the steps necessary to carry out such a study from selection of reference populations and preprocessing of data through to the testing itself. We detected one significant result with a Bonferroni corrected p-value of 0.032 at single nucleotide polymorphism rs12639065. Computing local ancestry for Hispanic populations was challenging because there are relatively few methods by which to handle 3-way admixture, and publicly available Native American reference panels are scarce. However, combining admixture and association is a promising approach for detection of quantitative trait loci because it might be able to elevate the power of detection by combining 2 different sources of genetic signal. PMID:25519335

  8. Geographic Patterns of Genome Admixture in Latin American Mestizos

    PubMed Central

    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

  9. Admixture mapping in two Mexican samples identifies significant associations of locus ancestry with triglyceride levels in the BUD13/ZNF259/APOA5 region and fine mapping points to rs964184 as the main driver of the association signal.

    PubMed

    Parra, Esteban J; Mazurek, Andrew; Gignoux, Christopher R; Sockell, Alexandra; Agostino, Michael; Morris, Andrew P; Petty, Lauren E; Hanis, Craig L; Cox, Nancy J; Valladares-Salgado, Adan; Below, Jennifer E; Cruz, Miguel

    2017-01-01

    We carried out an admixture mapping study of lipid traits in two samples from Mexico City. Native American locus ancestry was significantly associated with triglyceride levels in a broad region of chromosome 11 overlapping the BUD13, ZNF259 and APOA5 genes. In our fine-mapping analysis of this region using dense genome-wide data, rs964184 is the only marker included in the 99% credible set of SNPs, providing strong support for rs964184 as the causal variant within this region. The frequency of the allele associated with increased triglyceride concentrations (rs964184-G) is between 30-40% higher in Native American populations from Mexico than in European populations. The evidence currently available for this variant indicates that it may be exerting its effect through three potential mechanisms: 1) modification of enhancer activity, 2) regulation of the expression of several genes in cis and/or trans, or 3) modification of the methylation patterns of the promoter of the APOA5 gene.

  10. Admixture mapping in two Mexican samples identifies significant associations of locus ancestry with triglyceride levels in the BUD13/ZNF259/APOA5 region and fine mapping points to rs964184 as the main driver of the association signal

    PubMed Central

    Mazurek, Andrew; Sockell, Alexandra; Morris, Andrew P.; Petty, Lauren E.; Hanis, Craig L.; Cox, Nancy J.; Cruz, Miguel

    2017-01-01

    We carried out an admixture mapping study of lipid traits in two samples from Mexico City. Native American locus ancestry was significantly associated with triglyceride levels in a broad region of chromosome 11 overlapping the BUD13, ZNF259 and APOA5 genes. In our fine-mapping analysis of this region using dense genome-wide data, rs964184 is the only marker included in the 99% credible set of SNPs, providing strong support for rs964184 as the causal variant within this region. The frequency of the allele associated with increased triglyceride concentrations (rs964184-G) is between 30–40% higher in Native American populations from Mexico than in European populations. The evidence currently available for this variant indicates that it may be exerting its effect through three potential mechanisms: 1) modification of enhancer activity, 2) regulation of the expression of several genes in cis and/or trans, or 3) modification of the methylation patterns of the promoter of the APOA5 gene. PMID:28245265

  11. Risk for rheumatic disease in relation to ethnicity and admixture

    PubMed Central

    Molokhia, Mariam; McKeigue, Paul

    2000-01-01

    Risk of systemic lupus erythematosus (SLE) is high in west Africans compared with Europeans, and risk of rheumatoid arthritis (RA) is high in Native Americans compared with Europeans. These differences are not accounted for by differences in allele or haplotype frequencies in the human leucocyte antigen (HLA) region or any other loci known to influence risk of rheumatic disease. Where there has been admixture between two or more ethnic groups that differ in risk of disease, studies of the relationship of disease risk to proportionate admixture can help to distinguish between genetic and environmental explanations for ethnic differences in disease risk and to map the genes underlying these differences. PMID:11094421

  12. Admixture analysis in relation to pedigree studies of introgression in a minority British cattle breed: the Lincoln Red.

    PubMed

    Bray, T C; Hall, S J G; Bruford, M W

    2014-02-01

    Investigation of historic population processes using molecular data has been facilitated by the use of approximate Bayesian computation (ABC), which enables the consideration of multiple alternative demographic scenarios. The Lincoln Red cattle breed provides a relatively simple example of two well-documented admixture events. Using molecular data for this breed, we found that structure did not resolve very low (<5% levels) of introgression, possibly due to sampling limitations. We evaluated the performance of two ABC approaches (2BAD and DIYABC) against those of two earlier methodologies, ADMIX and LEADMIX, by comparing their interpretations with the conclusions drawn from herdbook analysis. The ABC methods gave credible values for the proportions of the Lincoln Red genotype that are attributable to Aberdeen Angus and Limousin, although estimates of effective population size and event timing were not realistic. We suggest ABC methods are a valuable supplement to pedigree-based studies but that the accuracy of admixture determination is likely to diminish with increasing complexity of the admixture scenario.

  13. Stability study of azlocillin sodium in glass bottles and PVC bags containing intravenous admixtures.

    PubMed

    Puiggròs Boldú, S; Pujol Cubells, M; Girona Brumós, V; Prat Aixelà, J; Muñoz Juncosa, M

    1995-09-01

    The kinetics of degradation of azlocillin sodium in four intravenous admixtures was investigated at different temperatures. The effect of temperature has been determined and from this data, by applying of Arrhenius-law, the stability of azlocillin sodium at 25 degrees C has been predicted and the t90 was determined. Admixtures containing azlocillin sodium (0.01 g ml-1) were prepared in 0.9% sodium chloride injection, in 5% dextrose solution, in 5% levulose solution and in Ringer's lactate solution. The admixtures were stored at 30 degrees, 40 degrees and 50 degrees C in either polyvinyl chloride bags and glass bottles. The change in the initial azlocillin sodium concentration was related to the type of intravenous solution. No dependence with material of container was found. After 24 hours, the change in the initial concentration of penicillin was less than 10% of the initial concentration in 0.9% sodium chloride and 5% levulose solution. However in Ringer's lactate and 5% glucose solution the t90 was lower. These results were found in agreement with experimental ones obtained at room temperature.

  14. The Complex Admixture History and Recent Southern Origins of Siberian Populations

    PubMed Central

    Pugach, Irina; Matveev, Rostislav; Spitsyn, Viktor; Makarov, Sergey; Novgorodov, Innokentiy; Osakovsky, Vladimir; Stoneking, Mark; Pakendorf, Brigitte

    2016-01-01

    Although Siberia was inhabited by modern humans at an early stage, there is still debate over whether it remained habitable during the extreme cold of the Last Glacial Maximum or whether it was subsequently repopulated by peoples with recent shared ancestry. Previous studies of the genetic history of Siberian populations were hampered by the extensive admixture that appears to have taken place among these populations, because commonly used methods assume a tree-like population history and at most single admixture events. Here we analyze geogenetic maps and use other approaches to distinguish the effects of shared ancestry from prehistoric migrations and contact, and develop a new method based on the covariance of ancestry components, to investigate the potentially complex admixture history. We furthermore adapt a previously devised method of admixture dating for use with multiple events of gene flow, and apply these methods to whole-genome genotype data from over 500 individuals belonging to 20 different Siberian ethnolinguistic groups. The results of these analyses indicate that there have been multiple layers of admixture detectable in most of the Siberian populations, with considerable differences in the admixture histories of individual populations. Furthermore, most of the populations of Siberia included here, even those settled far to the north, appear to have a southern origin, with the northward expansions of different populations possibly being driven partly by the advent of pastoralism, especially reindeer domestication. These newly developed methods to analyze multiple admixture events should aid in the investigation of similarly complex population histories elsewhere. PMID:26993256

  15. The Complex Admixture History and Recent Southern Origins of Siberian Populations.

    PubMed

    Pugach, Irina; Matveev, Rostislav; Spitsyn, Viktor; Makarov, Sergey; Novgorodov, Innokentiy; Osakovsky, Vladimir; Stoneking, Mark; Pakendorf, Brigitte

    2016-07-01

    Although Siberia was inhabited by modern humans at an early stage, there is still debate over whether it remained habitable during the extreme cold of the Last Glacial Maximum or whether it was subsequently repopulated by peoples with recent shared ancestry. Previous studies of the genetic history of Siberian populations were hampered by the extensive admixture that appears to have taken place among these populations, because commonly used methods assume a tree-like population history and at most single admixture events. Here we analyze geogenetic maps and use other approaches to distinguish the effects of shared ancestry from prehistoric migrations and contact, and develop a new method based on the covariance of ancestry components, to investigate the potentially complex admixture history. We furthermore adapt a previously devised method of admixture dating for use with multiple events of gene flow, and apply these methods to whole-genome genotype data from over 500 individuals belonging to 20 different Siberian ethnolinguistic groups. The results of these analyses indicate that there have been multiple layers of admixture detectable in most of the Siberian populations, with considerable differences in the admixture histories of individual populations. Furthermore, most of the populations of Siberia included here, even those settled far to the north, appear to have a southern origin, with the northward expansions of different populations possibly being driven partly by the advent of pastoralism, especially reindeer domestication. These newly developed methods to analyze multiple admixture events should aid in the investigation of similarly complex population histories elsewhere.

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

    SciTech Connect

    Wyrzykowski, Mateusz; Trtik, Pavel; Münch, Beat; Weiss, Jason; Vontobel, Peter; Lura, Pietro

    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.

  17. An RP-HPLC-UV method with SPE for cefotaxime in all-in-one total parenteral nutritional admixtures: application to stability studies.

    PubMed

    Iqbal, Muhammad Shahid; Bahari, Mohd Baidi; Darwis, Yusrida; Iqbal, Muhammad Zahid; Hayat, Amer; Venkatesh, Gantala

    2013-01-01

    A simple and selective RP-HPLC-UV method with SPE was developed and validated for the quantification of cefotaxime in all-in-one total parenteral nutrition (AIO-TPN) admixtures. Chromatographic separation was achieved on a 5 pm particle size C18 DB column (250 x 4.6 mm id) using the mobile phase ammonium acetate (25 mM, pH 4.0)-50% acetonitrile in methanol (80 + 20, v/v). The flow rate was 0.9 mL/min and the detection wavelength was 254 nm. The analyte was extracted from AIO-TPN admixtures by means of an SPE method. The cefotaxime calibration curve was linear over a concentration range of 100-1400 microg/mL with a correlation coefficient of > or = 0.9994. The intraday accuracy and precision for cefotaxime were < or = -3.15 and < or = 3.08%, respectively, whereas the interday accuracy and precision were < or = -2.48 and < or = 2.25%, respectively. The method was successfully applied to stability studies of cefotaxime in the presence of micronutrients together with low and high concentrations of macronutrients in AIO-TPN admixtures. Cefotaxime was degraded by 13.00 and 26.05% at room temperature (25 +/- 2 degrees C) after 72 h in low and high macronutrient concentration formulations of AIO-TPN admixtures, respectively. The values of cefotaxime degradation rates for low and high macronutrient concentration formulations of AIO-TPN admixtures were -0.164 and -0.353, respectively. These results indicated that there was a higher rate of degradation in the AIO-TPN admixture formulations containing high concentrations of macronutrients.

  18. Numerical and experimental study on the dynamics of a μs helium plasma gun with various amounts of O2 admixture

    NASA Astrophysics Data System (ADS)

    Viegas, Pedro; Damany, Xavier; Iseni, Sylvain; Pouvesle, Jean-Michel; Robert, Eric; Bourdon, Anne

    2016-09-01

    The use of admixtures (mostly O2 and N2) to a helium buffer has been studied recently to tailor the generation of reactive species in plasma jets for biomedical applications. So far, most experiments have been dedicated to the study of the plasma plume. For endoscopic treatments, it is also important to better understand and optimize the propagation of discharges in long dielectric tubes as catheters. In this work, we present an experimental and numerical study on the dynamics of a μs helium plasma discharge with O2 admixture in a long dielectric tube. In simulations, a 2D fluid model is used. For comparison purposes, the geometries of the set-ups used for simulations and experiments are as close as possible. We compare experiments and simulations for different amounts of O2 admixture added to the buffer gas and present results on the velocity of the discharge front for the various amounts of O2 and different applied voltages. In order to study the influence of different amounts of O2 admixture on the helium discharge dynamics, detailed kinetic schemes have been used. The influence of Penning and charge exchange reactions on the discharge structure and dynamics are studied, as well as the role of negative ions. P.V. is supported by an EDOM fellowship, and X.D. by an INEL/Region Centre-Val de Loire fellowship.

  19. Studies on growth, structural, dielectric, laser damage threshold, linear and nonlinear optical properties of methylene blue admixtured l-arginine phosphate single crystal.

    PubMed

    Peramaiyan, G; Pandi, P; Bhagavannarayana, G; Mohan Kumar, R

    2012-12-01

    L-Arginine phosphate (LAP) and methylene blue dye admixtured L-arginine phosphate single crystals were grown by slow cooling technique and their cell parameters, crystalline perfection, dopant inclusion were confirmed by single crystal, powder X-ray diffraction and high resolution X-ray diffraction analyses respectively. The modes of vibrations of different functional groups present in pure and dye admixtured LAP crystals have been identified by FTIR spectral analysis. The UV-Vis-NIR spectral study was performed on the grown crystals and found that the crystals are transparent in the entire visible-NIR region. The dielectric measurement was carried out on the grown crystals as a function of frequency at room temperature. The microhardness hardness study on (100) plane of grown crystals reveals the mechanical behavior of the crystals. The laser damage threshold value significantly enhanced for dye admixtured crystal in comparison with pure LAP crystal. The relative SHG efficiency of methylane blue admixtured LAP crystal was found to be 1.3 times higher than that of pure LAP crystal.

  20. Development of a panel of genome-wide ancestry informative markers to study admixture throughout the Americas.

    PubMed

    Galanter, Joshua Mark; Fernandez-Lopez, Juan Carlos; Gignoux, Christopher R; Barnholtz-Sloan, Jill; Fernandez-Rozadilla, Ceres; Via, Marc; Hidalgo-Miranda, Alfredo; Contreras, Alejandra V; Figueroa, Laura Uribe; Raska, Paola; Jimenez-Sanchez, Gerardo; Zolezzi, Irma Silva; Torres, Maria; Ponte, Clara Ruiz; Ruiz, Yarimar; Salas, Antonio; Nguyen, Elizabeth; Eng, Celeste; Borjas, Lisbeth; Zabala, William; Barreto, Guillermo; González, Fernando Rondón; Ibarra, Adriana; Taboada, Patricia; Porras, Liliana; Moreno, Fabián; Bigham, Abigail; Gutierrez, Gerardo; Brutsaert, Tom; León-Velarde, Fabiola; Moore, Lorna G; Vargas, Enrique; Cruz, Miguel; Escobedo, Jorge; Rodriguez-Santana, José; Rodriguez-Cintrón, William; Chapela, Rocio; Ford, Jean G; Bustamante, Carlos; Seminara, Daniela; Shriver, Mark; Ziv, Elad; Burchard, Esteban Gonzalez; Haile, Robert; Parra, Esteban; Carracedo, Angel

    2012-01-01

    Most individuals throughout the Americas are admixed descendants of Native American, European, and African ancestors. Complex historical factors have resulted in varying proportions of ancestral contributions between individuals within and among ethnic groups. We developed a panel of 446 ancestry informative markers (AIMs) optimized to estimate ancestral proportions in individuals and populations throughout Latin America. We used genome-wide data from 953 individuals from diverse African, European, and Native American populations to select AIMs optimized for each of the three main continental populations that form the basis of modern Latin American populations. We selected markers on the basis of locus-specific branch length to be informative, well distributed throughout the genome, capable of being genotyped on widely available commercial platforms, and applicable throughout the Americas by minimizing within-continent heterogeneity. We then validated the panel in samples from four admixed populations by comparing ancestry estimates based on the AIMs panel to estimates based on genome-wide association study (GWAS) data. The panel provided balanced discriminatory power among the three ancestral populations and accurate estimates of individual ancestry proportions (R² > 0.9 for ancestral components with significant between-subject variance). Finally, we genotyped samples from 18 populations from Latin America using the AIMs panel and estimated variability in ancestry within and between these populations. This panel and its reference genotype information will be useful resources to explore population history of admixture in Latin America and to correct for the potential effects of population stratification in admixed samples in the region.

  1. Genome-wide admixture and association study of serum iron, ferritin, transferrin saturation and total iron binding capacity in African Americans.

    PubMed

    Li, Jin; Lange, Leslie A; Duan, Qing; Lu, Yurong; Singleton, Andrew B; Zonderman, Alan B; Evans, Michele K; Li, Yun; Taylor, Herman A; Willis, Monte S; Nalls, Mike; Wilson, James G; Lange, Ethan M

    2015-01-15

    Iron is an essential component of many important proteins and enzymes, including hemoglobin, which is responsible for carrying oxygen to the cells. African Americans (AAs) have a greater prevalence of iron deficiency compared with European Americans. We conducted genome-wide admixture-mapping and association studies for serum iron, serum ferritin, transferrin saturation (SAT) and total iron binding capacity (TIBC) in 2347 AAs participating in the Jackson Heart Study (JHS). Follow-up replication analyses for JHS iron-trait associated SNPs were conducted in 329 AA participants in the Healthy Aging in Neighborhoods of Diversity across the Life Span study (HANDLS). Higher estimated proportions of global African ancestry were significantly associated with lower levels of iron (P = 2.4 × 10(-5)), SAT (P = 0.0019) and TIBC (P = 0.042). We observed significant associations (P < 5 × 10(-8)) between serum TIBC levels and two independent SNPs around TF on chromosome 3, the first report of a genome-wide significant second independent signal in this region, and SNPs near two novel genes: HDGFL1 on chromosome 6 and MAF on chromosome 16. We also observed significant associations between ferritin levels and SNPs near GAB3 on chromosome X. We replicated our two independent associations at TF and our association at GAB3 in HANDLS. Our study provides evidence for both shared and unique genetic risk factors that are associated with iron-related measures in AAs. The top two variants in TF explain 11.2% of the total variation in TIBC levels in AAs after accounting for age, gender, body mass index and background ancestry.

  2. Development of a Panel of Genome-Wide Ancestry Informative Markers to Study Admixture Throughout the Americas

    PubMed Central

    Galanter, Joshua Mark; Fernandez-Lopez, Juan Carlos; Gignoux, Christopher R.; Barnholtz-Sloan, Jill; Fernandez-Rozadilla, Ceres; Via, Marc; Hidalgo-Miranda, Alfredo; Contreras, Alejandra V.; Figueroa, Laura Uribe; Raska, Paola; Jimenez-Sanchez, Gerardo; Silva Zolezzi, Irma; Torres, Maria; Ponte, Clara Ruiz; Ruiz, Yarimar; Salas, Antonio; Nguyen, Elizabeth; Eng, Celeste; Borjas, Lisbeth; Zabala, William; Barreto, Guillermo; Rondón González, Fernando; Ibarra, Adriana; Taboada, Patricia; Porras, Liliana; Moreno, Fabián; Bigham, Abigail; Gutierrez, Gerardo; Brutsaert, Tom; León-Velarde, Fabiola; Moore, Lorna G.; Vargas, Enrique; Cruz, Miguel; Escobedo, Jorge; Rodriguez-Santana, José; Rodriguez-Cintrón, William; Chapela, Rocio; Ford, Jean G.; Bustamante, Carlos; Seminara, Daniela; Shriver, Mark; Ziv, Elad; Gonzalez Burchard, Esteban; Haile, Robert

    2012-01-01

    Most individuals throughout the Americas are admixed descendants of Native American, European, and African ancestors. Complex historical factors have resulted in varying proportions of ancestral contributions between individuals within and among ethnic groups. We developed a panel of 446 ancestry informative markers (AIMs) optimized to estimate ancestral proportions in individuals and populations throughout Latin America. We used genome-wide data from 953 individuals from diverse African, European, and Native American populations to select AIMs optimized for each of the three main continental populations that form the basis of modern Latin American populations. We selected markers on the basis of locus-specific branch length to be informative, well distributed throughout the genome, capable of being genotyped on widely available commercial platforms, and applicable throughout the Americas by minimizing within-continent heterogeneity. We then validated the panel in samples from four admixed populations by comparing ancestry estimates based on the AIMs panel to estimates based on genome-wide association study (GWAS) data. The panel provided balanced discriminatory power among the three ancestral populations and accurate estimates of individual ancestry proportions (R2>0.9 for ancestral components with significant between-subject variance). Finally, we genotyped samples from 18 populations from Latin America using the AIMs panel and estimated variability in ancestry within and between these populations. This panel and its reference genotype information will be useful resources to explore population history of admixture in Latin America and to correct for the potential effects of population stratification in admixed samples in the region. PMID:22412386

  3. Study on performance of concrete with over-burnt bricks aggregates and micro-silica admixture

    NASA Astrophysics Data System (ADS)

    Praveen, K.; Sathyan, Dhanya; Mini, K. M.

    2016-09-01

    Concrete is made by mixing cement, sand, aggregates and water in required proportion, where aggregates occupy the major volume. Addition of aggregates in concrete improves properties of concrete. With the natural resources depleting rapidly, limiting the use of natural resources and enhancing the use of waste materials is very important for sustainable development. Over-burnt bricks are a waste material which cannot be used in construction directly because of their irregular shape and dark colour. Use of over-burnt bricks helps to preserve natural aggregate source. The present study focuses on the effects of microsilica at various percentages as a partial cement replacement in concrete with over-burnt bricks as coarse aggregates. The mechanical properties of hardened concrete such as splitting tensile strength, flexural strength and compressive strength are studied and analyzed.

  4. Cartographic mapping study

    NASA Technical Reports Server (NTRS)

    Wilson, C.; Dye, R.; Reed, L.

    1982-01-01

    The errors associated with planimetric mapping of the United States using satellite remote sensing techniques are analyzed. Assumptions concerning the state of the art achievable for satellite mapping systems and platforms in the 1995 time frame are made. An analysis of these performance parameters is made using an interactive cartographic satellite computer model, after first validating the model using LANDSAT 1 through 3 performance parameters. An investigation of current large scale (1:24,000) US National mapping techniques is made. Using the results of this investigation, and current national mapping accuracy standards, the 1995 satellite mapping system is evaluated for its ability to meet US mapping standards for planimetric and topographic mapping at scales of 1:24,000 and smaller.

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

    PubMed

    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.

  6. Chemical composition, effective atomic number and electron density study of trommel sieve waste (TSW), Portland cement, lime, pointing and their admixtures with TSW in different proportions.

    PubMed

    Kurudirek, Murat; Aygun, Murat; Erzeneoğlu, Salih Zeki

    2010-06-01

    The trommel sieve waste (TSW) which forms during the boron ore production is considered to be a promising building material with its use as an admixture with Portland cement and is considered to be an alternative radiation shielding material, also. Thus, having knowledge on the chemical composition and radiation interaction properties of TSW as compared to other building materials is of importance. In the present study, chemical compositions of the materials used have been determined using a wavelength dispersive X-ray fluorescence spectrometer (WDXRFS). Also, TSW, some commonly used building materials (Portland cement, lime and pointing) and their admixtures with TSW have been investigated in terms of total mass attenuation coefficients (mu/rho), photon interaction cross sections (sigma(t)), effective atomic numbers (Z(eff)) and effective electron densities (N(e)) by using X-rays at 22.1, 25keV and gamma-rays at 88keV photon energies. Possible conclusions were drawn with respect to the variations in photon energy and chemical composition.

  7. Polymorphic Admixture Typing in Human Ethnic Populations

    PubMed Central

    Dean, Michael; Stephens, J. Claiborne; Winkler, Cheryl; Lomb, Deborah A.; Ramsburg, Mark; Boaze, Raleigh; Stewart, Claudia; Charbonneau, Lauren; Goldman, David; Albaugh, Bernard J.; Goedert, James J.; Beasley, R. Palmer; Hwang, Lu-Yu; Buchbinder, Susan; Weedon, Michael; Johnson, Patricia A.; Eichelberger, Mary; O'Brien, Stephen J.

    1994-01-01

    A panel of 257 RFLP loci was selected on the basis of high heterozygosity in Caucasian DNA surveys and equivalent spacing throughout the human genome. Probes from each locus were used in a Southern blot survey of allele frequency distribution for four human ethnic groups: Caucasian, African American, Asian (Chinese), and American Indian (Cheyenne). Nearly all RFLP loci were polymorphic in each group, albeit with a broad range of differing allele frequencies (δ). The distribution of frequency differences (δ values) was used for three purposes: (1) to provide estimates for genetic distance (differentiation) among these ethnic groups, (2) to revisit with a large data set the proportion of human genetic variation attributable to differentiation within ethnic groups, and (3) to identify loci with high δ values between recently admixed populations of use in mapping by admixture linkage disequilibrium (MALD). Although most markers display significant allele frequency differences between ethnic groups, the overall genetic distances between ethnic groups were small (.066–.098), and <10% of the measured overall molecular genetic diversity in these human samples can be attributed to “racial” differentiation. The median δ values for pairwise comparisons between groups fell between .15 and .20, permitting identification of highly informative RFLP loci for MALD disease association studies. PMID:7942857

  8. Alkali-silicate admixture for cement composites incorporating pozzolan or blast furnace slag

    SciTech Connect

    Zivica, V. . Inst. of construction and Architecture)

    1993-09-01

    This research was devoted to the study of the influence of the developed alkali-silicate admixture (AS admixture) on mortar properties. The obtained results shown that the admixture significantly increased the strength of the mortars made from portland cement (PC) and silica fume (SF) or blast furnace slag (SL). For example after 24 h hardening of mortar (30% SF + 70% PC), with the admixture, reached value of compression strength 18,7 MPa opposite to the value of 5.6 MPa of control mortar (100% PC). The same accelerating effect of AS admixture was observed also with mortar incorporating slag and with slag mortar (100% SL). Further results show that the mortars with AS admixture had an increased content of hydration products and substantially more dense pore structure than mortars of the same composition, but without the admixture.

  9. Sagittal Abdominal Diameter as a Surrogate Marker of Insulin Resistance in an Admixtured Population—Brazilian Metabolic Syndrome Study (BRAMS)

    PubMed Central

    Cassani, Roberta S. L.; Forti, Adriana C. e; Vilela, Brunna S.; Tambascia, Marcos Antonio

    2015-01-01

    Background Sagittal abdominal diameter (SAD) has been proposed as a surrogate marker of insulin resistance (IR). However, the utilization of SAD requires specific validation for each ethnicity. We aimed to investigate the potential use of SAD, compared with classical anthropometrical parameters, as a surrogate marker of IR and to establish the cutoff values of SAD for screening for IR. Methods A multicenter population survey on metabolic disorders was conducted. A race-admixtured sample of 824 adult women was assessed. The anthropometric parameters included: BMI, waist circumference (WC), waist-to-hip ratio and SAD. IR was determined by a hyperglycemic clamp and the HOMA-IR index. Results After adjustments for age and total body fat mass, SAD (r = 0.23 and r = -0.70) and BMI (r = 0.20 and r = -0.71) were strongly correlated with the IR measured by the HOMA-IR index and the clamp, respectively (p < 0.001). In the ROC analysis, the optimal cutoff for SAD in women was 21.0 cm. The women with an increased SAD presented 3.2 (CI 95%: 2.1-5.0) more likelihood of having IR, assessed by the HOMA-IR index compared with those with normal SAD (p < 0.001); whereas women with elevated BMI and WC were 2.1 (95% CI: 1.4-3.3) and 2.8 (95% CI: 1.7-4.5) more likely to have IR (p < 0.001), respectively. No statistically significant results were found for waist-to-hip ratio. Conclusions SAD can be a suitable surrogate marker of IR. Understanding and applying routine and simplified methods is essential because IR is associated with an increased risk of obesity-related diseases even in the presence of normal weight, slight overweight, as well as in obesity. Further prospective analysis will need to verify SAD as a determinant of clinical outcomes, such as type 2 diabetes and cardiovascular events, in the Brazilian population. PMID:25951458

  10. A Spatial Framework for Understanding Population Structure and Admixture

    PubMed Central

    Bradburd, Gideon S.; Ralph, Peter L.; Coop, Graham M.

    2016-01-01

    Geographic patterns of genetic variation within modern populations, produced by complex histories of migration, can be difficult to infer and visually summarize. A general consequence of geographically limited dispersal is that samples from nearby locations tend to be more closely related than samples from distant locations, and so genetic covariance often recapitulates geographic proximity. We use genome-wide polymorphism data to build “geogenetic maps,” which, when applied to stationary populations, produces a map of the geographic positions of the populations, but with distances distorted to reflect historical rates of gene flow. In the underlying model, allele frequency covariance is a decreasing function of geogenetic distance, and nonlocal gene flow such as admixture can be identified as anomalously strong covariance over long distances. This admixture is explicitly co-estimated and depicted as arrows, from the source of admixture to the recipient, on the geogenetic map. We demonstrate the utility of this method on a circum-Tibetan sampling of the greenish warbler (Phylloscopus trochiloides), in which we find evidence for gene flow between the adjacent, terminal populations of the ring species. We also analyze a global sampling of human populations, for which we largely recover the geography of the sampling, with support for significant histories of admixture in many samples. This new tool for understanding and visualizing patterns of population structure is implemented in a Bayesian framework in the program SpaceMix. PMID:26771578

  11. Maps and Map Learning in Social Studies

    ERIC Educational Resources Information Center

    Bednarz, Sarah Witham; Acheson, Gillian; Bednarz, Robert S.

    2006-01-01

    The importance of maps and other graphic representations has become more important to geography and geographers. This is due to the development and widespread diffusion of geographic (spatial) technologies. As computers and silicon chips have become more capable and less expensive, geographic information systems (GIS), global positioning satellite…

  12. Experimental and numerical study on the dynamics of a μs helium plasma gun discharge with various amounts of N2 admixture

    NASA Astrophysics Data System (ADS)

    Bourdon, Anne; Darny, Thibault; Robert, Eric; Pechereau, Francois; Viegas, Pedro; Pouvesle, Jean-Michel

    2015-09-01

    These last years, atmospheric pressure plasma jets formed by pulsed helium discharges ignited in thin dielectric tubes have been extensively studied due to their potential for biomedical applications. So far, most experiments have been dedicated to the study of the plasma plume. For endoscopic treatments, it is also important to better understand and optimize the propagation of discharges in long dielectric tubes as catheters. First we present an experimental and numerical study on the dynamics of a μs helium plasma discharge with N2 admixture in a long dielectric tube. We compare the velocity of the discharge front for various amounts of N2 and different applied voltages and show a good agreement between experiments and simulations. Second, we compare time-resolved measurements and simulations of longitudinal and radial electric fields associated with plasma propagation in the dielectric tube and in the plasma plume. It is interesting to note that measurements obtained with a probe located outside the dielectric tube are in excellent agreement with simulations. This allows to infer from simulations the time evolution of the electric field on the discharge axis which is a key parameter for applications. The authors acknowledge the computational resources of the Mesocentre of Ecole Centrale Paris.

  13. Topological Signatures for Population Admixture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Topological Signatures for Population AdmixtureDeniz Yorukoglu1, Filippo Utro1, David Kuhn2, Saugata Basu3 and Laxmi Parida1* Abstract Background: As populations with multi-linear transmission (i.e., mixing of genetic material from two parents, say) evolve over generations, the genetic transmission...

  14. EOS mapping accuracy study

    NASA Technical Reports Server (NTRS)

    Forrest, R. B.; Eppes, T. A.; Ouellette, R. J.

    1973-01-01

    Studies were performed to evaluate various image positioning methods for possible use in the earth observatory satellite (EOS) program and other earth resource imaging satellite programs. The primary goal is the generation of geometrically corrected and registered images, positioned with respect to the earth's surface. The EOS sensors which were considered were the thematic mapper, the return beam vidicon camera, and the high resolution pointable imager. The image positioning methods evaluated consisted of various combinations of satellite data and ground control points. It was concluded that EOS attitude control system design must be considered as a part of the image positioning problem for EOS, along with image sensor design and ground image processing system design. Study results show that, with suitable efficiency for ground control point selection and matching activities during data processing, extensive reliance should be placed on use of ground control points for positioning the images obtained from EOS and similar programs.

  15. Lightning mapping sensor study

    NASA Technical Reports Server (NTRS)

    Norwood, V.

    1983-01-01

    A technology assessment to determine how a world-wide, continuous measurement of lightning could be achieved from a geostationary platform is provided. Various approaches to the detector sensors are presented. It was first determined that any existing detector chips would require some degree of modification in order to meet the lightning mapper sensor requirements. The elements of the system were then analyzed, categorized, and graded for study emphasis. The recommended approach for the lightning mapper sensor is to develop a monolithic array in which each detector cell has circuitry that implements a two-step photon-collecting method for a very high dynamic range with good measurement accuracy. The efficiency of the array is compatible with the use of a conventional refractive optics design having an aperture in the neighborhood of 7 to 10 cm.

  16. Heterogeneity in Genetic Admixture across Different Regions of Argentina

    PubMed Central

    Avena, Sergio; Via, Marc; Ziv, Elad; Pérez-Stable, Eliseo J.; Gignoux, Christopher R.; Dejean, Cristina; Huntsman, Scott; Torres-Mejía, Gabriela; Dutil, Julie; Matta, Jaime L.; Beckman, Kenneth; Burchard, Esteban González; Parolin, María Laura; Goicoechea, Alicia; Acreche, Noemí; Boquet, Mariel; Ríos Part, María Del Carmen; Fernández, Vanesa; Rey, Jorge; Stern, Mariana C.; Carnese, Raúl F.; Fejerman, Laura

    2012-01-01

    The population of Argentina is the result of the intermixing between several groups, including Indigenous American, European and African populations. Despite the commonly held idea that the population of Argentina is of mostly European origin, multiple studies have shown that this process of admixture had an impact in the entire Argentine population. In the present study we characterized the distribution of Indigenous American, European and African ancestry among individuals from different regions of Argentina and evaluated the level of discrepancy between self-reported grandparental origin and genetic ancestry estimates. A set of 99 autosomal ancestry informative markers (AIMs) was genotyped in a sample of 441 Argentine individuals to estimate genetic ancestry. We used non-parametric tests to evaluate statistical significance. The average ancestry for the Argentine sample overall was 65% European (95%CI: 63–68%), 31% Indigenous American (28–33%) and 4% African (3–4%). We observed statistically significant differences in European ancestry across Argentine regions [Buenos Aires province (BA) 76%, 95%CI: 73–79%; Northeast (NEA) 54%, 95%CI: 49–58%; Northwest (NWA) 33%, 95%CI: 21–41%; South 54%, 95%CI: 49–59%; p<0.0001] as well as between the capital and immediate suburbs of Buenos Aires city compared to more distant suburbs [80% (95%CI: 75–86%) versus 68% (95%CI: 58–77%), p = 0.01]. European ancestry among individuals that declared all grandparents born in Europe was 91% (95%CI: 88–94%) compared to 54% (95%CI: 51–57%) among those with no European grandparents (p<0.001). Our results demonstrate the range of variation in genetic ancestry among Argentine individuals from different regions in the country, highlighting the importance of taking this variation into account in genetic association and admixture mapping studies in this population. PMID:22506044

  17. Maximum-likelihood estimation of admixture proportions from genetic data.

    PubMed Central

    Wang, Jinliang

    2003-01-01

    For an admixed population, an important question is how much genetic contribution comes from each parental population. Several methods have been developed to estimate such admixture proportions, using data on genetic markers sampled from parental and admixed populations. In this study, I propose a likelihood method to estimate jointly the admixture proportions, the genetic drift that occurred to the admixed population and each parental population during the period between the hybridization and sampling events, and the genetic drift in each ancestral population within the interval between their split and hybridization. The results from extensive simulations using various combinations of relevant parameter values show that in general much more accurate and precise estimates of admixture proportions are obtained from the likelihood method than from previous methods. The likelihood method also yields reasonable estimates of genetic drift that occurred to each population, which translate into relative effective sizes (N(e)) or absolute average N(e)'s if the times when the relevant events (such as population split, admixture, and sampling) occurred are known. The proposed likelihood method also has features such as relatively low computational requirement compared with previous ones, flexibility for admixture models, and marker types. In particular, it allows for missing data from a contributing parental population. The method is applied to a human data set and a wolflike canids data set, and the results obtained are discussed in comparison with those from other estimators and from previous studies. PMID:12807794

  18. Ancient Admixture in Human History

    PubMed Central

    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

  19. Effectiveness of mineral admixtures in reducing ASR expansion

    SciTech Connect

    Xu, G.J.Z.; Watt, D.F.; Hudec, P.P.

    1995-08-01

    This paper investigates the effectiveness of eight mineral admixtures in reducing the alkali silica(te) reactivity of cement mortar. The admixtures include one class F fly ash, a condensed silica fume, a ground fiberglass, three glass containing waste materials, and two inert fillers (carbon and calcium carbonate). Mortar bar expansion, the change in evaporable water content, the evidence of reaction and the composition of reaction products were studied. It was found that shale is the only reactive component of the sand and the effectiveness of admixtures in reducing alkali-silica reaction depends largely on the chemical composition of the admixtures. Ground fiberglass is very effective in controlling the alkali silica reaction, while inert fillers have only a dilution effect. It is thought that admixtures reduce ASR expansion by two reactions: (1) pozzolanic reaction that reduces the permeability of concrete and entraps some fraction of the alkali ions; (2) alkali silica reaction that consumes most of the available alkali ions and thereby prevents the reaction between alkalis and aggregate.

  20. Numerical and experimental study of the dynamics of a μs helium plasma gun discharge with various amounts of N2 admixture

    NASA Astrophysics Data System (ADS)

    Bourdon, Anne; Darny, Thibault; Pechereau, François; Pouvesle, Jean-Michel; Viegas, Pedro; Iséni, Sylvain; Robert, Eric

    2016-06-01

    This paper presents a combined 2D numerical and experimental study of the influence of {{\\text{N}}2} admixture on the dynamics of a He-{{\\text{N}}2} discharge in the 10 cm long dielectric tube of a plasma gun set-up. First, the comparison between experiments and simulations is carried out on the ionization front propagation velocity in the tube. The importance of taking into account a detailed kinetic scheme for the He-{{\\text{N}}2} mixture in the simulations to obtain a good agreement with the experiments is put forward. For the μs driven plasma gun, the two- and three-body Penning reactions occurring in the plasma column behind the ionization front, are shown to play a key role on the discharge dynamics. In the experiments and simulations, the significant influence of the amplitude of the applied voltage on the ionization front propagation velocity is observed. As the amount of {{\\text{N}}2} varies, simulation results show that the ionization front velocity, depends on a complex coupling between the kinetics of the discharge, the photoionization and the 2D structure of the discharge in the tube. Finally, the time evolution of axial and radial components of the electric field measured by an electro-optic probe set outside the tube are compared with simulation results. A good agreement is obtained on both components of the electric field. In the tube, simulations show that the magnitude of the axial electric field on the discharge axis depends weakly on the amount of {{\\text{N}}2} conversely to the magnitude of the off-axis peak electric field. Both, simulations and first measurements in the tube or within the plasma plume show peak electric fields of the order of 45 kV·cm-1.

  1. Crystal growth, structural and thermal studies of amino acids admixtured L-arginine phosphate monohydrate single crystals

    NASA Astrophysics Data System (ADS)

    Anandan, P.; Saravanan, T.; Parthipan, G.; Kumar, R. Mohan; Bhagavannarayana, G.; Ravi, G.; Jayavel, R.

    2011-05-01

    To study the improved characteristics of L-arginine phosphate monohydrate (LAP) crystals, amino acids mixed LAP crystals have been grown by slow cooling method. Amino acids like glycine, L-alanine, and L-valine have been selected for doping. Optical quality bulk crystals have been harvested after a typical growth period of about twenty days. The effect of amino acids in the crystal lattice and molecular vibrational frequencies of various functional groups in the crystals have been studied using X-ray powder diffraction and Fourier Transform infrared (FTIR) analyses respectively. Thermal behavior of the amino acids mixed LAP crystals have been studied from the TG and DTG analyses. High-resolution X-ray diffraction studies have been carried out to find the crystalline nature. Optical transmission studies have been carried out by UV-vis spectrophotometer. The cut off wavelength is below 240 nm for the grown crystals.

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

    PubMed

    Verdu, Paul; Pemberton, Trevor J; Laurent, Romain; Kemp, Brian M; Gonzalez-Oliver, Angelica; Gorodezky, Clara; Hughes, Cris E; Shattuck, Milena R; Petzelt, Barbara; Mitchell, Joycelynn; Harry, Harold; William, Theresa; Worl, Rosita; Cybulski, Jerome S; Rosenberg, Noah A; Malhi, Ripan S

    2014-08-01

    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.

  3. Patterns of Admixture and Population Structure in Native Populations of Northwest North America

    PubMed Central

    Verdu, Paul; Pemberton, Trevor J.; Laurent, Romain; Kemp, Brian M.; Gonzalez-Oliver, Angelica; Gorodezky, Clara; Hughes, Cris E.; Shattuck, Milena R.; Petzelt, Barbara; Mitchell, Joycelynn; Harry, Harold; William, Theresa; Worl, Rosita; Cybulski, Jerome S.; Rosenberg, Noah A.; Malhi, Ripan S.

    2014-01-01

    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. PMID:25122539

  4. Admixtures

    DTIC Science & Technology

    1970-07-01

    dercc by the hariv.:oeristics of the cmicnt and ag-prgate and thcJr relative proportions, as vrell as by terporature, humidity, and curing ." In Aup-t...cemont to fortA ccnttious compotids. The most ca’-.i polzzbm in flyaush, the residue frcm burning po--dored coal In thhea-ml poier plants. Smns naturrI...doteraine V effect of tciupeaturc. on creep or concrt -te. Recent work in ]Dropa and Israel I surest that creep increeos as a result of teperature

  5. Strong selection at MHC in Mexicans since admixture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mexicans are a recent admixture of Amerindians, Europeans, and Africans. We performed local ancestry analysis of Mexican samples from two genome-wide association studies obtained from dbGaP, and discovered that at the major histocompatibility complex (MHC) region Mexicans have excessive African ance...

  6. Worldwide patterns of genomic variation and admixture in gray wolves

    PubMed Central

    Fan, Zhenxin; Silva, Pedro; Gronau, Ilan; Wang, Shuoguo; Armero, Aitor Serres; Schweizer, Rena M.; Ramirez, Oscar; Pollinger, John; Galaverni, Marco; Ortega Del-Vecchyo, Diego; Du, Lianming; Zhang, Wenping; Zhang, Zhihe; Xing, Jinchuan; Vilà, Carles; Marques-Bonet, Tomas; Godinho, Raquel; Yue, Bisong; Wayne, Robert K.

    2016-01-01

    The gray wolf (Canis lupus) is a widely distributed top predator and ancestor of the domestic dog. To address questions about wolf relationships to each other and dogs, we assembled and analyzed a data set of 34 canine genomes. The divergence between New and Old World wolves is the earliest branching event and is followed by the divergence of Old World wolves and dogs, confirming that the dog was domesticated in the Old World. However, no single wolf population is more closely related to dogs, supporting the hypothesis that dogs were derived from an extinct wolf population. All extant wolves have a surprisingly recent common ancestry and experienced a dramatic population decline beginning at least ∼30 thousand years ago (kya). We suggest this crisis was related to the colonization of Eurasia by modern human hunter–gatherers, who competed with wolves for limited prey but also domesticated them, leading to a compensatory population expansion of dogs. We found extensive admixture between dogs and wolves, with up to 25% of Eurasian wolf genomes showing signs of dog ancestry. Dogs have influenced the recent history of wolves through admixture and vice versa, potentially enhancing adaptation. Simple scenarios of dog domestication are confounded by admixture, and studies that do not take admixture into account with specific demographic models are problematic. PMID:26680994

  7. Leaching of concrete admixtures containing thiocyanate and resin acids.

    PubMed

    Andersson, A C; Stromvall, A M

    2001-02-15

    There is an increasing concern about the emission of pollutants during the construction and lifetime of buildings. The leaching of concrete admixtures containing thiocyanate and resin acids was studied using standard leaching tests and chemical analysis. Ecotoxicological risk was assessed for each admixture. Thiocyanate leaching from concrete, with a chlorine-free accelerating admixture, was determined by ion chromatography. Of the total amount of thiocyanate added, 6-8% was emitted within 30 d. The thiocyanate diffusion curve indicates a fast dissolution process from the surface layer, followed by a slower continuous diffusion process. Thiocyanate exhibits both acute and chronic toxicity, which makes it of immediate environmental concern. Resin acid leaching from concrete test specimens containing an admixture of air-entraining agents with tall oil was determined by solid-phase extraction, methylation, and GC/MS. Of added resin acids, 10% was emitted over 143 d. The leaching curves for the resin acids indicate a continuous diffusion that is proportional to the square root of time and follows Fick's first law of diffusion. The chemical composition of the resin acids in the leachate demonstrates degradation and rearrangement of the resin acids during diffusion. Resin acids emitted from concrete are of environmental concern because they are persistent and have the ability to bioaccumulate in aquatic organisms.

  8. Worldwide patterns of genomic variation and admixture in gray wolves.

    PubMed

    Fan, Zhenxin; Silva, Pedro; Gronau, Ilan; Wang, Shuoguo; Armero, Aitor Serres; Schweizer, Rena M; Ramirez, Oscar; Pollinger, John; Galaverni, Marco; Ortega Del-Vecchyo, Diego; Du, Lianming; Zhang, Wenping; Zhang, Zhihe; Xing, Jinchuan; Vilà, Carles; Marques-Bonet, Tomas; Godinho, Raquel; Yue, Bisong; Wayne, Robert K

    2016-02-01

    The gray wolf (Canis lupus) is a widely distributed top predator and ancestor of the domestic dog. To address questions about wolf relationships to each other and dogs, we assembled and analyzed a data set of 34 canine genomes. The divergence between New and Old World wolves is the earliest branching event and is followed by the divergence of Old World wolves and dogs, confirming that the dog was domesticated in the Old World. However, no single wolf population is more closely related to dogs, supporting the hypothesis that dogs were derived from an extinct wolf population. All extant wolves have a surprisingly recent common ancestry and experienced a dramatic population decline beginning at least ∼30 thousand years ago (kya). We suggest this crisis was related to the colonization of Eurasia by modern human hunter-gatherers, who competed with wolves for limited prey but also domesticated them, leading to a compensatory population expansion of dogs. We found extensive admixture between dogs and wolves, with up to 25% of Eurasian wolf genomes showing signs of dog ancestry. Dogs have influenced the recent history of wolves through admixture and vice versa, potentially enhancing adaptation. Simple scenarios of dog domestication are confounded by admixture, and studies that do not take admixture into account with specific demographic models are problematic.

  9. The relationship between European genetic admixture and body composition among Hispanics and Native Americans.

    PubMed

    Klimentidis, Y C; Miller, G F; Shriver, M D

    2009-01-01

    Previous studies have shown a relationship between health-related phenotypes and the degree of African, European, or Native American genetic admixture, indicating that there may be a genetic component to these phenotypes. However, these relationships may be driven to a large extent by the environmental differences that co-vary with admixture differences between and within groups. In this study, we examine the relationship between genetic admixture and two phenotypic measurements that are potentially related to health: body mass index (BMI) and percent body fat (PBF). In addition to admixture proportions, we attempt to assess the influence of some environmental covariates by examining how the phenotypes vary with self-reported household income, education of parents, and physical activity level. Genetic, anthropometric, and environmental data were collected from 170 self-reported Hispanic and Native American university students in Albuquerque, NM. We examine the relationships between genetic admixture, phenotype, and environment in both the full sample, as well as in Hispanics and Native Americans separately. Among Hispanics, we find no significant relationship between genetic admixture and body composition. Among Native Americans, despite a small sample size, we find a statistically significant, negative relationship between European genetic admixture and PBF and BMI, after adjusting for other predictor variables. We compare our findings to previous research, and discuss their implications for understanding health disparities within and between ethnic groups.

  10. Genetic admixture studies on four in situ evolved, two migrant and twenty-one ethnic populations of Tamil Nadu, south India.

    PubMed

    Suhasini, G; Sonaa, E; Shila, S; Srikumari, C R; Jayaraman, G; Ramesh, A

    2011-08-01

    We analysed the genetic structure of ≈ 1000 samples representing 27 ethnic groups settled in Tamil Nadu, south India, derived from two linguistic families (Dravidians and Indo-Europeans) representing four religious groups (Hinduism, Islam, Christianity and Jainism) using 11 mtDNA markers. Out of 27 ethnic groups, four are in situ populations (Anglo-Indian, Labbai Muslim, Nadar Christian and south Indian Jain) and two are migrants (Gypsy and north Indian Jain) from north India to Tamil Nadu, and 21 are native ethnic groups. Six of the markers we used were monomorphic (HaeIII663, HpaI3592, AluI5176, AluI7025, AluI13262, 9-bp deletion) and five markers were polymorphic (DdeI10394, AluI10397, HinfI12308, HincII13259 and HaeIII16517). Haplogroup frequencies, genetic affinities and admixture analysis are based on the genotype data of polymorphic markers observed in these populations. Haplogroup frequencies indicate that various ethnic groups entered Tamil Nadu during different time periods. Genetic affinities and admixture estimates revealed that the ethnic groups possessing advanced knowledge of farming cluster in a branch (C), and could be the late arrived settlers as agriculture, was introduced to this region at about 5 to 3 thousand years ago. In situ ethnic groups appear to have arisen at various times as a result of the prevailing dominant socio-cultural forces. Hierarchical Hindu caste system created many ethnic groups in the history of its existence; some of them became isolated for considerable period of time. Over all, among Tamil ethnic groups, in spite of caste systems' rigidity, built in flexibility in the system in the form of hypergamy and hypogamy had allowed maternal gene flow between them.

  11. Interethnic admixture and the evolution of Latin American populations

    PubMed Central

    Salzano, Francisco Mauro; Sans, Mónica

    2014-01-01

    A general introduction to the origins and history of Latin American populations is followed by a systematic review of the data from molecular autosomal assessments of the ethnic/continental (European, African, Amerindian) ancestries for 24 Latin American countries or territories. The data surveyed are of varying quality but provide a general picture of the present constitution of these populations. A brief discussion about the applications of these results (admixture mapping) is also provided. Latin American populations can be viewed as natural experiments for the investigation of unique anthropological and epidemiological issues. PMID:24764751

  12. Common Mapping System Media Study

    DTIC Science & Technology

    1994-04-01

    CMS standiard, including mission plaMing, intelligence, and avionics systems . The distribution media types supported by CMS will significantly iumat...the utility and cost of CMS for these systems . This paper presents the results of an investigation into the attributes of candidate distribution media...Common Mapping System ( CMS ) defines data formats and standard distribution media for the storage, interchange, and retrieval of MCG&I data. A variety of

  13. Admixture enhanced controlled low-strength material for direct underwater injection with minimal cross-contamination

    SciTech Connect

    Hepworth, H.K.; Davidson, J.S.; Hooyman, J.L.

    1997-03-01

    Commercially available admixtures have been developed for placing traditional concrete products under water. This paper evaluates adapting anti-washout admixture (AWA) and high range water reducing admixture (HRWRA) products to enhance controlled low-strength materials (CLSMs) for underwater placement. A simple experimental scale model (based on dynamic and geometric similitude) of typical grout pump emplacement equipment has been developed to determine the percentage of cementing material washed out. The objective of this study was to identify proportions of admixtures and underwater CLSM emplacement procedures which would minimize the cross-contamination of the displaced water while maintaining the advantages of CLSM. Since the displaced water from radioactively contaminated systems must be subsequently treated prior to release to the environment, the amount of cross-contamination is important for cases in which cementing material could form hard sludges in a water treatment facility and contaminate the in-place CLSM stabilization medium.

  14. Admixture facilitates genetic adaptations to high altitude in Tibet

    PubMed Central

    Jeong, Choongwon; Alkorta-Aranburu, Gorka; Basnyat, Buddha; Neupane, Maniraj; Witonsky, David B.; Pritchard, Jonathan K.; Beall, Cynthia M.; Di Rienzo, Anna

    2015-01-01

    Admixture is recognized as a widespread feature of human populations, renewing interest in the possibility that genetic exchange can facilitate adaptations to new environments. Studies of Tibetans revealed candidates for high-altitude adaptations in the EGLN1 and EPAS1 genes, associated with lower hemoglobin concentration. However, the history of these variants or that of Tibetans remains poorly understood. Here, we analyze genotype data for the Nepalese Sherpa, and find that Tibetans are a mixture of ancestral populations related to the Sherpa and Han Chinese. EGLN1 and EPAS1 genes show a striking enrichment of high-altitude ancestry in the Tibetan genome, indicating that migrants from low altitude acquired adaptive alleles from the highlanders. Accordingly, the Sherpa and Tibetans share adaptive hemoglobin traits. This admixture-mediated adaptation shares important features with adaptive introgression. Therefore, we identify a novel mechanism, beyond selection on new mutations or on standing variation, through which populations can adapt to local environments. PMID:24513612

  15. Ancestry informative markers clarify the regional admixture variation in the Costa Rican population.

    PubMed

    Cámpos-Sanchez, Rebeca; Raventós, Henriette; Barrantes, Ramiro

    2013-10-01

    The genetic structure of Costa Rica's population is complex, both by region and by individual, due to the admixture process that started during the 15th century and historical events thereafter. Previous studies have been done mostly on Amerindian populations and the Central Valley inhabitants using various microsatellites and mitochondrial DNA markers. Here, we study for the first time a random sample from all regions of the country with ancestry informative markers (AIMs) to address the individual and regional admixture proportions. A sample of 160 male individuals was screened for 78 AIMs customized in a GoldenGate platform from Illumina. We observed that this small set of AIMs has the same power of hundreds of microsatellites and thousands of single-nucleotide polymorphisms to evaluate admixture, with the benefit of reducing genotyping costs. This type of investigation is necessary to explore new genetic markers useful for forensic and genetic investigation. Our data showed a mean admixture proportion of 49.2% European (EUR), 37.8% Native American (NAM), and 12.9% African (AFR), with a disproportionate admixture composition by region. In addition, when Chinese (CHB) was included as a fourth component, the proportions changed to 45.6% EUR, 33.5% NAM, 11.7% AFR, and 9.2% CHB. The admixture trend is consistent among all regions (EUR > NAM > AFR), and individual admixture estimates vary broadly in each region. Though we did not find stratification in Costa Rica's population, gene admixture should be evaluated in future genetic studies of Costa Rica, especially for the Caribbean region, as it contains the largest proportion of African ancestry (30.9%).

  16. Adsorption of superplasticizer admixtures on alkali-activated slag pastes

    SciTech Connect

    Palacios, M. Houst, Y.F.; Bowen, P.; Puertas, F.

    2009-08-15

    Alkali-activated slag (AAS) binders are obtained by a manufacturing process less energy-intensive than ordinary Portland cement (OPC) and involves lower greenhouse gasses emission. These alkaline cements allow the production of high mechanical strength and durable concretes. In the present work, the adsorption of different superplasticizer admixtures (naphthalene-based, melamine-based and a vinyl copolymer) on the slag particles in AAS pastes using alkaline solutions with different pH values have been studied in detail. The effect of the superplasticizers on the yield stress and plastic viscosity of the AAS and OPC pastes have been also evaluated. The results obtained allowed us to conclude that the adsorption of the superplasticizers on AAS pastes is independent of the pH of the alkaline solutions used and lower than on OPC pastes. However, the effect of the admixtures on the rheological parameters depends directly on the type and dosage of the superplasticizer as well as of the binder used and, in the case of the AAS, on the pH of the alkaline activator solution. In 11.7-pH NaOH-AAS pastes the dosages of the superplasticizers required to attain similar reduction in the yield stress are ten-fold lower than for Portland cement. In this case the superplasticizers studied show a fluidizing effect considerably higher in 11.7-pH NaOH-AAS pastes than in OPC pastes. In 13.6-pH NaOH-AAS pastes, the only admixture observed to affect the rheological parameters is the naphthalene-based admixture due to its higher chemical stability in such extremely alkaline media.

  17. Effect of Waterproofing Admixtures on the Flexural Strength and Corrosion Resistance of Concrete

    NASA Astrophysics Data System (ADS)

    Geetha, A.; Perumal, P.

    2012-02-01

    This paper deals about the flexural strength and corrosion behaviour of concrete using waterproofing admixtures. The effect of waterproofing admixtures on the corrosion behaviour of RCC specimen has been studied by conducting accelerated corrosion test. To identify the effect of corrosion in pull out strength, corrosion process was induced by means of accelerated corrosion procedure. To accelerate the reinforcement corrosion, direct electric current was impressed on the rebar embedded in the specimen using a DC power supply system that has a facility to adjust voltage. The addition of waterproofing admixtures also shows the improvement in the flexural strength of concrete has been studied by conducting flexural strength tests on the concrete prism specimen of size 100 × 100 × 500 mm with and without admixtures for various dosages and various curing periods of 7 and 28 days. The results showed that the presence of waterproofing admixtures always improves the corrosion resistance and thus increases the strength of concrete due to the hydrophobic action of waterproofing admixtures.

  18. Estimating ethnic admixture from pedigree data.

    PubMed

    Sinsheimer, Janet S; Plaisier, Christopher L; Huertas-Vazquez, Adriana; Aguilar-Salinas, Carlos; Tusie-Luna, Teresa; Pajukanta, Päivi; Lange, Kenneth

    2008-03-01

    This paper introduces a likelihood method of estimating ethnic admixture that uses individuals, pedigrees, or a combination of individuals and pedigrees. For each founder of a pedigree, admixture proportions are calculated by conditioning on the pedigree-wide genotypes at all ancestry-informative markers. These estimates are then propagated down the pedigree to the nonfounders by a simple averaging process. The large-sample standard errors of the founders' proportions can be similarly transformed into standard errors for the admixture proportions of the descendants. These standard errors are smaller than the corresponding standard errors when each individual is treated independently. Both hard and soft information on a founder's ancestry can be accommodated in this scheme, which has been implemented in the genetic software package Mendel. The utility of the method is demonstrated on simulated data and a real data example involving Mexican families of mixed Amerindian and Spanish ancestry.

  19. Principal component analysis under population genetic models of range expansion and admixture.

    PubMed

    François, Olivier; Currat, Mathias; Ray, Nicolas; Han, Eunjung; Excoffier, Laurent; Novembre, John

    2010-06-01

    In a series of highly influential publications, Cavalli-Sforza and colleagues used principal component (PC) analysis to produce maps depicting how human genetic diversity varies across geographic space. Within Europe, the first axis of variation (PC1) was interpreted as evidence for the demic diffusion model of agriculture, in which farmers expanded from the Near East approximately 10,000 years ago and replaced the resident hunter-gatherer populations with little or no interbreeding. These interpretations of the PC maps have been recently questioned as the original results can be reproduced under models of spatially covarying allele frequencies without any expansion. Here, we study PC maps for data simulated under models of range expansion and admixture. Our simulations include a spatially realistic model of Neolithic farmer expansion and assume various levels of interbreeding between farmer and resident hunter-gatherer populations. An important result is that under a broad range of conditions, the gradients in PC1 maps are oriented along a direction perpendicular to the axis of the expansion, rather than along the same axis as the expansion. We propose that this surprising pattern is an outcome of the "allele surfing" phenomenon, which creates sectors of high allele-frequency differentiation that align perpendicular to the direction of the expansion.

  20. Population divergence with or without admixture: selecting models using an ABC approach

    PubMed Central

    Sousa, V C; Beaumont, M A; Fernandes, P; Coelho, M M; Chikhi, L

    2012-01-01

    Genetic data have been widely used to reconstruct the demographic history of populations, including the estimation of migration rates, divergence times and relative admixture contribution from different populations. Recently, increasing interest has been given to the ability of genetic data to distinguish alternative models. One of the issues that has plagued this kind of inference is that ancestral shared polymorphism is often difficult to separate from admixture or gene flow. Here, we applied an approximate Bayesian computation (ABC) approach to select the model that best fits microsatellite data among alternative splitting and admixture models. We performed a simulation study and showed that with reasonably large data sets (20 loci) it is possible to identify with a high level of accuracy the model that generated the data. This suggests that it is possible to distinguish genetic patterns due to past admixture events from those due to shared polymorphism (population split without admixture). We then apply this approach to microsatellite data from an endangered and endemic Iberian freshwater fish species, in which a clustering analysis suggested that one of the populations could be admixed. In contrast, our results suggest that the observed genetic patterns are better explained by a population split model without admixture. PMID:22146980

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

    PubMed Central

    Claudio-Campos, Karla; Rivera-Miranda, Giselle; Bermúdez-Bosch, Luis; Renta, Jessicca Y.; Cadilla, Carmen L.; Cruz, Iadelisse; Feliu, Juan F.; Vergara, Cunegundo; Ruaño, Gualberto

    2016-01-01

    Aim This study is aimed at developing a novel admixture-adjusted pharmacogenomic approach to individually refine warfarin dosing in Caribbean Hispanic patients. Patients & Methods 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. Results 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). Conclusions 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. Trial Registration ClinicalTrials.gov NCT01318057 PMID:26745506

  2. Beyond 2/3 and 1/3: The Complex Signatures of Sex-Biased Admixture on the X Chromosome.

    PubMed

    Goldberg, Amy; Rosenberg, Noah A

    2015-09-01

    Sex-biased demography, in which parameters governing migration and population size differ between females and males, has been studied through comparisons of X chromosomes, which are inherited sex-specifically, and autosomes, which are not. A common form of sex bias in humans is sex-biased admixture, in which at least one of the source populations differs in its proportions of females and males contributing to an admixed population. Studies of sex-biased admixture often examine the mean ancestry for markers on the X chromosome in relation to the autosomes. A simple framework noting that in a population with equally many females and males, two-thirds of X chromosomes appear in females, suggests that the mean X-chromosomal admixture fraction is a linear combination of female and male admixture parameters, with coefficients 2/3 and 1/3, respectively. Extending a mechanistic admixture model to accommodate the X chromosome, we demonstrate that this prediction is not generally true in admixture models, although it holds in the limit for an admixture process occurring as a single event. For a model with constant ongoing admixture, we determine the mean X-chromosomal admixture, comparing admixture on female and male X chromosomes to corresponding autosomal values. Surprisingly, in reanalyzing African-American genetic data to estimate sex-specific contributions from African and European sources, we find that the range of contributions compatible with the excess African ancestry on the X chromosome compared to autosomes has a wide spread, permitting scenarios either without male-biased contributions from Europe or without female-biased contributions from Africa.

  3. Beyond 2/3 and 1/3: The Complex Signatures of Sex-Biased Admixture on the X Chromosome

    PubMed Central

    Goldberg, Amy; Rosenberg, Noah A.

    2015-01-01

    Sex-biased demography, in which parameters governing migration and population size differ between females and males, has been studied through comparisons of X chromosomes, which are inherited sex-specifically, and autosomes, which are not. A common form of sex bias in humans is sex-biased admixture, in which at least one of the source populations differs in its proportions of females and males contributing to an admixed population. Studies of sex-biased admixture often examine the mean ancestry for markers on the X chromosome in relation to the autosomes. A simple framework noting that in a population with equally many females and males, two-thirds of X chromosomes appear in females, suggests that the mean X-chromosomal admixture fraction is a linear combination of female and male admixture parameters, with coefficients 2/3 and 1/3, respectively. Extending a mechanistic admixture model to accommodate the X chromosome, we demonstrate that this prediction is not generally true in admixture models, although it holds in the limit for an admixture process occurring as a single event. For a model with constant ongoing admixture, we determine the mean X-chromosomal admixture, comparing admixture on female and male X chromosomes to corresponding autosomal values. Surprisingly, in reanalyzing African-American genetic data to estimate sex-specific contributions from African and European sources, we find that the range of contributions compatible with the excess African ancestry on the X chromosome compared to autosomes has a wide spread, permitting scenarios either without male-biased contributions from Europe or without female-biased contributions from Africa. PMID:26209245

  4. Cold Weather Admixture Systems Demonstration at Fort Wainwright, Alaska

    DTIC Science & Technology

    2010-08-01

    oz/cwt. Rheocrete® CNI is a corrosion inhibiting admixture (BASF 2007b). While corrosion inhibitors are used to protect embedded steel members...Washington, DC 20314-1000 ERDC/CRREL TR-10-6 ii Abstract: Cold Weather Admixture Systems (CWAS) is a new approach to cold weather concreting that...incorporates suites of commercially avail- able chemical admixtures in concrete mixes. When used in combination, these admixtures depress the freezing

  5. A study of the antisymmetric QRT mappings

    NASA Astrophysics Data System (ADS)

    Willox, R.; Grammaticos, B.; Ramani, A.

    2005-06-01

    We study a particular class of the mappings introduced by Quispel, Roberts and Thompson that come from a two-component system but can be naturally reduced to a one-component one. We classify all these mappings on the basis of the canonical forms of the QRT matrices. We also present the extension of these systems to nonautonomous forms, which are usually discrete Painlevé equations.

  6. A genetic atlas of human admixture history

    PubMed Central

    Hellenthal, Garrett; Busby, George B.J.; Band, Gavin; Wilson, James F.; Capelli, Cristian

    2014-01-01

    Modern genetic data combined with appropriate statistical methods have the potential to contribute substantially to our understanding of human history. We have developed an approach that exploits the genomic structure of admixed populations to date and characterize historical mixture events at fine scales. We used this to produce an atlas of worldwide human admixture history, constructed using genetic data alone and encompassing over 100 events occurring over the past 4,000 years. We identify events whose dates and participants suggest they describe genetic impacts of the Mongol Empire, Arab slave trade, Bantu expansion, first millennium CE migrations in eastern Europe, and European colonialism, as well as unrecorded events, revealing admixture to be an almost universal force shaping human populations. PMID:24531965

  7. Assessment of coyote-wolf-dog admixture using ancestry-informative diagnostic SNPs

    PubMed Central

    Monzón, J.; Kays, R.; Dykhuizen, D. E.

    2014-01-01

    The evolutionary importance of hybridization as a source of new adaptive genetic variation is rapidly gaining recognition. Hybridization between coyotes and wolves may have introduced adaptive alleles into the coyote gene pool that facilitated an expansion in their geographic range and dietary niche. Furthermore, hybridization between coyotes and domestic dogs may facilitate adaptation to human-dominated environments. We genotyped 63 ancestry-informative single nucleotide polymorphisms in 427 canids in order to examine the prevalence, spatial distribution, and ecology of admixture in eastern coyotes. Using multivariate methods and Bayesian clustering analyses, we estimated the relative contributions of western coyotes, western and eastern wolves, and domestic dogs to the admixed ancestry of Ohio and eastern coyotes. We found that eastern coyotes form an extensive hybrid swarm, with all our samples having varying levels of admixture. Ohio coyotes, previously thought to be free of admixture, are also highly admixed with wolves and dogs. Coyotes in areas of high deer density are genetically more wolf-like, suggesting that natural selection for wolf-like traits may result in local adaptation at a fine geographic scale. Our results, in light of other previously published studies of admixture in Canis, reveal a pattern of sex-biased hybridization, presumably generated by male wolves and dogs mating with female coyotes. This study is the most comprehensive genetic survey of admixture in eastern coyotes and demonstrates that the frequency and scope of hybridization can be quantified with relatively few ancestry-informative markers. PMID:24148003

  8. Assessment of coyote-wolf-dog admixture using ancestry-informative diagnostic SNPs.

    PubMed

    Monzón, J; Kays, R; Dykhuizen, D E

    2014-01-01

    The evolutionary importance of hybridization as a source of new adaptive genetic variation is rapidly gaining recognition. Hybridization between coyotes and wolves may have introduced adaptive alleles into the coyote gene pool that facilitated an expansion in their geographic range and dietary niche. Furthermore, hybridization between coyotes and domestic dogs may facilitate adaptation to human-dominated environments. We genotyped 63 ancestry-informative single-nucleotide polymorphisms in 427 canids to examine the prevalence, spatial distribution and the ecology of admixture in eastern coyotes. Using multivariate methods and Bayesian clustering analyses, we estimated the relative contributions of western coyotes, western and eastern wolves, and domestic dogs to the admixed ancestry of Ohio and eastern coyotes. We found that eastern coyotes form an extensive hybrid swarm, with all our samples having varying levels of admixture. Ohio coyotes, previously thought to be free of admixture, are also highly admixed with wolves and dogs. Coyotes in areas of high deer density are genetically more wolf-like, suggesting that natural selection for wolf-like traits may result in local adaptation at a fine geographic scale. Our results, in light of other previously published studies of admixture in Canis, revealed a pattern of sex-biased hybridization, presumably generated by male wolves and dogs mating with female coyotes. This study is the most comprehensive genetic survey of admixture in eastern coyotes and demonstrates that the frequency and scope of hybridization can be quantified with relatively few ancestry-informative markers.

  9. Complex Admixture Preceded and Followed the Extinction of Wisent in the Wild

    PubMed Central

    Hartmann, Stefanie; Paijmans, Johanna L. A.; Taron, Ulrike; Xenikoudakis, Georgios; Cahill, James A.; Heintzman, Peter D.; Shapiro, Beth; Baryshnikov, Gennady; Bunevich, Aleksei N.; Crees, Jennifer J.; Dobosz, Roland; Manaserian, Ninna; Okarma, Henryk; Tokarska, Małgorzata; Turvey, Samuel T.; Wójcik, Jan M.; Żyła, Waldemar; Szymura, Jacek M.; Hofreiter, Michael

    2017-01-01

    Retracing complex population processes that precede extreme bottlenecks may be impossible using data from living individuals. The wisent (Bison bonasus), Europe’s largest terrestrial mammal, exemplifies such a population history, having gone extinct in the wild but subsequently restored by captive breeding efforts. Using low coverage genomic data from modern and historical individuals, we investigate population processes occurring before and after this extinction. Analysis of aligned genomes supports the division of wisent into two previously recognized subspecies, but almost half of the genomic alignment contradicts this population history as a result of incomplete lineage sorting and admixture. Admixture between subspecies populations occurred prior to extinction and subsequently during the captive breeding program. Admixture with the Bos cattle lineage is also widespread but results from ancient events rather than recent hybridization with domestics. Our study demonstrates the huge potential of historical genomes for both studying evolutionary histories and for guiding conservation strategies. PMID:28007976

  10. Population evolution in 20th-century Easter Island: endogamy and admixture.

    PubMed

    Hernández, M; García-Moro, C; Moral, P; González-Martín, A

    2000-04-01

    We studied the 20th-century evolution of the Rapanui population of Easter Island, the most geographically isolated in the world, to analyze the current process of admixture. Using parochial birth records, we determined origin of the birth parents based on their surnames. The origin of parents reveals two stages of population evolution: endogamy, due to the isolation of the island, but with a strong rejection of isonymous marriages; and admixture, beginning in 1965 with the opening of the island to the rest of the world. We used Lasker's coefficient (Lasker's Ri) and the Shannon-Weaver coefficient of diversity (H) to characterize both stages. The gene flow evaluated from admixture has increased significantly since 1965. Births from exogamous unions represented 3.5% of total births from 1937 to 1965. increased to 43.2% between 1966 and 1980, and constituted 50.8% of all births between 1981 and 1996.

  11. Chemical stability of admixtures combining ziconotide with fentanyl or sufentanil during simulated intrathecal administration.

    PubMed

    Shields, David E; Aclan, Jennifer; Szatkowski, Aaron

    2008-01-01

    Although the U.S. Food and Drug Administration has not approved the combined use of intrathecal medications, practitioners frequently prescribe combination intrathecal therapy for patients who do not experience adequate analgesia with a single intrathecal agent; however, the chemical stability of an analgesic combination may influence the frequency of pump refills necessary to maintain safe and efective pain control. This investigation was performed to evaluate the chemical stability of admixtures containing 25 mcg/mL ziconotide and either 1000 mcg/mL fentanyl citrate or 1000 mcg/mL sufentanil citrate during simulated intrathecal infusion under laboratory conditions at 37 deg C. Admixtures were prepared from commercial ziconotide (25 mcg/mL) and lyophilized powders of the opioid drugs, sparged with nitrogen to remove dissolved oxygen, and stored in implantable intrathecal pumps at 37 deg C. Samples obtained at various intervals over the course of 40 days were assessed for drug concentrations by using high-performance liquid chromatography. The periods of time that the admixtures retained > or = 90% and > or = 80% of the initial concentrations of each drug (i.e., the 90% and 80% stabilities) were determined by using linear regression and 95% confidence intervals. At study end, ziconotide concentrations averaged 87.5% of the initial concentration in the ziconotide/fentanyl admixture and 89.3% of the initial concentration in the ziconotide/sufentanil admixture; opioid concentrations were unchanged. Ziconotide was 90% stable for 26 days and 80% stable for 58 days (extrapolated) when combined with fentanyl; when combined with sufentanil, ziconotide was 90% stable for 33 days and 80% stable for 68 days (extrapolated). The opioids were stable throughout the study. At the concentrations used in this study, ziconotide/fentanyl and ziconotide/sufentanil admixtures were relatively stable.

  12. New advanced shotcrete admixtures: Internal curing

    SciTech Connect

    Melbye, T.A.

    1995-12-31

    Tunnels and other underground construction projects have one of the worst curing conditions due to the ventilation that blows continuously dry (cold or hot) air into the tunnel. It can be compared with concrete exposed to a windy area. One would think that tunnels have ideal curing conditions with high humidity (water leakage), no wind and no sun exposure. However, this is not the case. MBT has developed a new system for more efficient and secure curing of wet shotcrete, repair mortars as well as concrete. Internal curing means that a special admixture is added to the concrete/mortar during batching as a normal admixture. This admixture produces an internal barrier in the shotcrete/concrete which secures safer hydration and better chemical resistance than the application of conventional curing agents. The benefits resulting from the new technology are impressive: The time consuming application and, in the case of various shotcrete layers, removal of curing agents are no longer necessary; curing is guaranteed from the very beginning of hydration; and there is no negative influence on bonding between layers. As a consequence of th is optimum curing effect, all other shotcrete characteristics are improved: density, final strengths, freeze/thaw and chemical resistances, watertightness, less cracking and shrinkage. In addition, MEYCO TCC 735 also improves pumpability and workability of shotcrete, even with low-grade aggregates. It particularly improves the pumpability of steel fiber reinforced shotcrete mixes. In combination with the MEYCO TCC system it contrives to even increase the beneficial effects of the slump killing system by further improving fiber orientation, reducing fiber rebound and thus raising toughness values.

  13. Ancestry, admixture and fitness in Colombian genomes.

    PubMed

    Rishishwar, Lavanya; Conley, Andrew B; Wigington, Charles H; Wang, Lu; Valderrama-Aguirre, Augusto; Jordan, I King

    2015-07-21

    The human dimension of the Columbian Exchange entailed substantial genetic admixture between ancestral source populations from Africa, the Americas and Europe, which had evolved separately for many thousands of years. We sought to address the implications of the creation of admixed American genomes, containing novel allelic combinations, for human health and fitness via analysis of an admixed Colombian population from Medellin. Colombian genomes from Medellin show a wide range of three-way admixture contributions from ancestral source populations. The primary ancestry component for the population is European (average = 74.6%, range = 45.0%-96.7%), followed by Native American (average = 18.1%, range = 2.1%-33.3%) and African (average = 7.3%, range = 0.2%-38.6%). Locus-specific patterns of ancestry were evaluated to search for genomic regions that are enriched across the population for particular ancestry contributions. Adaptive and innate immune system related genes and pathways are particularly over-represented among ancestry-enriched segments, including genes (HLA-B and MAPK10) that are involved in defense against endemic pathogens such as malaria. Genes that encode functions related to skin pigmentation (SCL4A5) and cutaneous glands (EDAR) are also found in regions with anomalous ancestry patterns. These results suggest the possibility that ancestry-specific loci were differentially retained in the modern admixed Colombian population based on their utility in the New World environment.

  14. Preferred reporting items for studies mapping onto preference-based outcome measures: The MAPS statement.

    PubMed

    Petrou, Stavros; Rivero-Arias, Oliver; Dakin, Helen; Longworth, Louise; Oppe, Mark; Froud, Robert; Gray, Alastair

    2015-08-01

    'Mapping' onto generic preference-based outcome measures is increasingly being used as a means of generating health utilities for use within health economic evaluations. Despite publication of technical guides for the conduct of mapping research, guidance for the reporting of mapping studies is currently lacking. The MAPS (MApping onto Preference-based measures reporting Standards) statement is a new checklist, which aims to promote complete and transparent reporting of mapping studies. The primary audiences for the MAPS statement are researchers reporting mapping studies, the funders of the research, and peer reviewers and editors involved in assessing mapping studies for publication.A de novo list of 29 candidate reporting items and accompanying explanations was created by a working group comprised of six health economists and one Delphi methodologist. Following a two-round, modified Delphi survey with representatives from academia, consultancy, health technology assessment agencies and the biomedical journal editorial community, a final set of 23 items deemed essential for transparent reporting, and accompanying explanations, was developed. The items are contained in a user friendly 23 item checklist. They are presented numerically and categorised within six sections, namely: (i) title and abstract; (ii) introduction; (iii) methods; (iv) results; (v) discussion; and (vi) other. The MAPS statement is best applied in conjunction with the accompanying MAPS explanation and elaboration document.It is anticipated that the MAPS statement will improve the clarity, transparency and completeness of reporting of mapping studies. To facilitate dissemination and uptake, the MAPS statement is being co-published by eight health economics and quality of life journals, and broader endorsement is encouraged. The MAPS working group plans to assess the need for an update of the reporting checklist in five years' time.This statement was published jointly in Applied Health Economics

  15. Preferred reporting items for studies mapping onto preference-based outcome measures: The MAPS statement.

    PubMed

    Petrou, Stavros; Rivero-Arias, Oliver; Dakin, Helen; Longworth, Louise; Oppe, Mark; Froud, Robert; Gray, Alastair

    2015-01-01

    'Mapping' onto generic preference-based outcome measures is increasingly being used as a means of generating health utilities for use within health economic evaluations. Despite publication of technical guides for the conduct of mapping research, guidance for the reporting of mapping studies is currently lacking. The MAPS (MApping onto Preference-based measures reporting Standards) statement is a new checklist, which aims to promote complete and transparent reporting of mapping studies. The primary audiences for the MAPS statement are researchers reporting mapping studies, the funders of the research, and peer reviewers and editors involved in assessing mapping studies for publication. A de novo list of 29 candidate reporting items and accompanying explanations was created by a working group comprised of six health economists and one Delphi methodologist. Following a two-round, modified Delphi survey with representatives from academia, consultancy, health technology assessment agencies and the biomedical journal editorial community, a final set of 23 items deemed essential for transparent reporting, and accompanying explanations, was developed. The items are contained in a user friendly 23 item checklist. They are presented numerically and categorised within six sections, namely: (i) title and abstract; (ii) introduction; (iii) methods; (iv) results; (v) discussion; and (vi) other. The MAPS statement is best applied in conjunction with the accompanying MAPS explanation and elaboration document. It is anticipated that the MAPS statement will improve the clarity, transparency and completeness of reporting of mapping studies. To facilitate dissemination and uptake, the MAPS statement is being co-published by seven health economics and quality of life journals, and broader endorsement is encouraged. The MAPS working group plans to assess the need for an update of the reporting checklist in five years' time.

  16. Preferred Reporting Items for Studies Mapping onto Preference-Based Outcome Measures: The MAPS Statement.

    PubMed

    Petrou, Stavros; Rivero-Arias, Oliver; Dakin, Helen; Longworth, Louise; Oppe, Mark; Froud, Robert; Gray, Alastair

    2015-10-01

    'Mapping' onto generic preference-based outcome measures is increasingly being used as a means of generating health utilities for use within health economic evaluations. Despite the publication of technical guides for the conduct of mapping research, guidance for the reporting of mapping studies is currently lacking. The MAPS (MApping onto Preference-based measures reporting Standards) statement is a new checklist, which aims to promote complete and transparent reporting of mapping studies. The primary audiences for the MAPS statement are researchers reporting mapping studies, the funders of the research, and peer reviewers and editors involved in assessing mapping studies for publication. A de novo list of 29 candidate reporting items and accompanying explanations was created by a working group comprising six health economists and one Delphi methodologist. Following a two-round modified Delphi survey with representatives from academia, consultancy, health technology assessment agencies and the biomedical journal editorial community, a final set of 23 items deemed essential for transparent reporting, and accompanying explanations, was developed. The items are contained in a user-friendly 23-item checklist. They are presented numerically and categorised within six sections, namely: (1) title and abstract; (2) introduction; (3) methods; (4) results; (5) discussion; and (6) other. The MAPS statement is best applied in conjunction with the accompanying MAPS explanation and elaboration document. It is anticipated that the MAPS statement will improve the clarity, transparency and completeness of reporting of mapping studies. To facilitate dissemination and uptake, the MAPS statement is being co-published by seven health economics and quality-of-life journals, and broader endorsement is encouraged. The MAPS working group plans to assess the need for an update of the reporting checklist in 5 years' time.

  17. A single-tube 27-plex SNP assay for estimating individual ancestry and admixture from three continents.

    PubMed

    Wei, Yi-Liang; Wei, Li; Zhao, Lei; Sun, Qi-Fan; Jiang, Li; Zhang, Tao; Liu, Hai-Bo; Chen, Jian-Gang; Ye, Jian; Hu, Lan; Li, Cai-Xia

    2016-01-01

    A single-tube multiplex assay of a small set of ancestry-informative markers (AIMs) for effectively estimating individual ancestry and admixture is an ideal forensic tool to trace the population origin of an unknown DNA sample. We present a newly developed 27-plex single nucleotide polymorphism (SNP) panel with highly robust and balanced differential power to perfectly assign individuals to African, European, and East Asian ancestries. Evaluating 968 previously described intercontinental AIMs from three HapMap population genotyping datasets (Yoruban in Ibadan, Nigeria (YRI); Utah residents with Northern and Western European ancestry from the Centre de'Etude du Polymorphism Humain (CEPH) collection (CEU); and Han Chinese in Beijing, China (CHB)), the best set of markers was selected on the basis of Hardy-Weinberg equilibrium (p > 0.00001), population-specific allele frequency (two of three δ values >0.5), according to linkage disequilibrium (r (2) < 0.2), and capable of being multiplexed in one tube and detected by capillary electrophoresis. The 27-SNP panel was first validated by assigning the ancestry of the 11 populations in the HapMap project. Then, we tested the 27-plex SNP assay with 1164 individuals from 17 additional populations. The results demonstrated that the SNP panel was successful for ancestry inference of individuals with African, European, and East Asian ancestry. Furthermore, the system performed well when inferring the admixture of Eurasians (EUR/EAS) after analyzing admixed populations from Xinjiang (Central Asian) as follows: Tajik (68:27), Uyghur (49:46), Kirgiz (40:57), and Kazak (36:60). For individual analyses, we interpreted each sample with a three-ancestry component percentage and a population match probability sequence. This multiplex assay is a convenient and cost-effective tool to assist in criminal investigations, as well as to correct for the effects of population stratification for case-control studies.

  18. Mapping Regional Drought Vulnerability: a Case Study

    NASA Astrophysics Data System (ADS)

    Karamouz, M.; Zeynolabedin, A.; Olyaei, M. A.

    2015-12-01

    Drought is among the natural disaster that causes damages and affects many people's life in many part of the world including in Iran. Recently, some factors such as climate variability and the impact of climate change have influenced drought frequency and intensity in many parts of the world. Drought can be divided into four categories of meteorological, hydrological, agricultural and social-economic. In meteorological the important feature is lack of rainfall. In hydrological drought river flows and dam storage are considered. Lack of soil moisture is the key factor in agricultural droughts while in social-economic type of drought the relation between supply and demand and social-economic damages due to water deficiency is studied. While the first three types relates to the lack of some hydrological characteristics, social-economic type of drought is actually the consequence of other types expressed in monetary values. Many indices are used in assessing drought; each has its own advantages and disadvantages and can be used for specific types of drought. Therefore knowing the types of drought can provide a better understanding of shortages and their characteristics. Drought vulnerability is a concept which shows the likelihood of damages from hazard in a particular place by focusing on the system status prior to the disaster. Drought vulnerability has been viewed as a potential for losses in the region due to water deficiency at the time of drought. In this study the application of vulnerability concept in drought management in East Azarbaijan province in Iran is investigated by providing vulnerability maps which demonstrates spatial characteristics of drought vulnerability. In the first step, certain governing parameters in drought analysis such as precipitation, temperature, land use, topography, solar radiation and ground water elevation have been investigated in the region. They are described in details and calculated in suitable time series. Vulnerabilities

  19. Inferring Admixture Histories of Human Populations Using Linkage Disequilibrium

    PubMed Central

    Loh, Po-Ru; Lipson, Mark; Patterson, Nick; Moorjani, Priya; Pickrell, Joseph K.; Reich, David; Berger, Bonnie

    2013-01-01

    Long-range migrations and the resulting admixtures between populations have been important forces shaping human genetic diversity. Most existing methods for detecting and reconstructing historical admixture events are based on allele frequency divergences or patterns of ancestry segments in chromosomes of admixed individuals. An emerging new approach harnesses the exponential decay of admixture-induced linkage disequilibrium (LD) as a function of genetic distance. Here, we comprehensively develop LD-based inference into a versatile tool for investigating admixture. We present a new weighted LD statistic that can be used to infer mixture proportions as well as dates with fewer constraints on reference populations than previous methods. We define an LD-based three-population test for admixture and identify scenarios in which it can detect admixture events that previous formal tests cannot. We further show that we can uncover phylogenetic relationships among populations by comparing weighted LD curves obtained using a suite of references. Finally, we describe several improvements to the computation and fitting of weighted LD curves that greatly increase the robustness and speed of the calculations. We implement all of these advances in a software package, ALDER, which we validate in simulations and apply to test for admixture among all populations from the Human Genome Diversity Project (HGDP), highlighting insights into the admixture history of Central African Pygmies, Sardinians, and Japanese. PMID:23410830

  20. Seismicity map tools for earthquake studies

    NASA Astrophysics Data System (ADS)

    Boucouvalas, Anthony; Kaskebes, Athanasios; Tselikas, Nikos

    2014-05-01

    We report on the development of new and online set of tools for use within Google Maps, for earthquake research. We demonstrate this server based and online platform (developped with PHP, Javascript, MySQL) with the new tools using a database system with earthquake data. The platform allows us to carry out statistical and deterministic analysis on earthquake data use of Google Maps and plot various seismicity graphs. The tool box has been extended to draw on the map line segments, multiple straight lines horizontally and vertically as well as multiple circles, including geodesic lines. The application is demonstrated using localized seismic data from the geographic region of Greece as well as other global earthquake data. The application also offers regional segmentation (NxN) which allows the studying earthquake clustering, and earthquake cluster shift within the segments in space. The platform offers many filters such for plotting selected magnitude ranges or time periods. The plotting facility allows statistically based plots such as cumulative earthquake magnitude plots and earthquake magnitude histograms, calculation of 'b' etc. What is novel for the platform is the additional deterministic tools. Using the newly developed horizontal and vertical line and circle tools we have studied the spatial distribution trends of many earthquakes and we here show for the first time the link between Fibonacci Numbers and spatiotemporal location of some earthquakes. The new tools are valuable for examining visualizing trends in earthquake research as it allows calculation of statistics as well as deterministic precursors. We plan to show many new results based on our newly developed platform.

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

    PubMed

    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.

  2. Admixture estimates for Caracas, Venezuela, based on autosomal, Y-chromosome, and mtDNA markers.

    PubMed

    Martínez, Helios; Rodríguez-Larralde, Alvaro; Izaguirre, Mary Helen; De Guerra, Dinorah Castro

    2007-04-01

    The present Venezuelan population is the product of admixture of Amerindians, Europeans, and Africans, a process that was not homogeneous throughout the country. Blood groups, short tandem repeats (STRs), mtDNA, and Y-chromosome markers have been used successfully in admixture studies, but few such studies have been conducted in Venezuela. In this study we aim to estimate the admixture components of samples from two different socioeconomic levels from Caracas, Venezuela's capital city, compare their differences, and infer sexual asymmetry in the European Amerindian union patterns. Gene frequencies for blood groups ABO and Rh (CDE) and for the STRs VWA, F13A01, and FES/FPS and mtDNA and Y-chromosome haplogroups were studied in a sample of 60 individuals living in Caracas, taken from a private clinic (high socioeconomic level), and 50 individuals, also living in Caracas, drawn from a public maternity clinic (low socioeconomic level). The admixture analysis for the five autosomal markers gives a high European component (0.78) and an almost negligible African sub-Saharan component (0.06) for the high socioeconomic level, whereas for the low socioeconomic level the sub-Saharan, European, and Amerindian components were 0.21, 0.42, and 0.36, respectively. Estimates of admixture based on mtDNA and Y-chromosome markers reveal that the Amerindian contribution to these Caracas samples is almost entirely through females, because the Y-chromosome Amerindian and African sub-Saharan chromosomes found in this study were scarce. Our study reveals that the identification of the grandparents' geographic origin is an important methodological aspect to take into account in genetic studies related to the reconstruction of historical events.

  3. Deciphering the fine-structure of tribal admixture in the Bedouin population using genomic data.

    PubMed

    Markus, B; Alshafee, I; Birk, O S

    2014-02-01

    The Bedouin Israeli population is highly inbred and structured with a very high prevalence of recessive diseases. Many studies in the past two decades focused on linkage analysis in large, multiple consanguineous pedigrees of this population. The advent of high-throughput technologies motivated researchers to search for rare variants shared between smaller pedigrees, integrating data from clinically similar yet seemingly non-related sporadic cases. However, such analyses are challenging because, without pedigree data, there is no prior knowledge regarding possible relatedness between the sporadic cases. Here, we describe models and techniques for the study of relationships between pedigrees and use them for the inference of tribal co-ancestry, delineating the complex social interactions between different tribes in the Negev Bedouins of southern Israel. Through our analysis, we differentiate between tribes that share many yet small genomic segments because of co-ancestry versus tribes that share larger segments because of recent admixture. The emergent pattern is well correlated with the prevalence of rare mutations in the different tribes. Tribes that do not intermarry, mostly because of social restrictions, hold private mutations, whereas tribes that do intermarry demonstrate a genetic flow of mutations between them. Thus, social structure within an inbred community can be delineated through genomic data, with implications to genetic counseling and genetic mapping.

  4. Deciphering the fine-structure of tribal admixture in the Bedouin population using genomic data

    PubMed Central

    Markus, B; Alshafee, I; Birk, O S

    2014-01-01

    The Bedouin Israeli population is highly inbred and structured with a very high prevalence of recessive diseases. Many studies in the past two decades focused on linkage analysis in large, multiple consanguineous pedigrees of this population. The advent of high-throughput technologies motivated researchers to search for rare variants shared between smaller pedigrees, integrating data from clinically similar yet seemingly non-related sporadic cases. However, such analyses are challenging because, without pedigree data, there is no prior knowledge regarding possible relatedness between the sporadic cases. Here, we describe models and techniques for the study of relationships between pedigrees and use them for the inference of tribal co-ancestry, delineating the complex social interactions between different tribes in the Negev Bedouins of southern Israel. Through our analysis, we differentiate between tribes that share many yet small genomic segments because of co-ancestry versus tribes that share larger segments because of recent admixture. The emergent pattern is well correlated with the prevalence of rare mutations in the different tribes. Tribes that do not intermarry, mostly because of social restrictions, hold private mutations, whereas tribes that do intermarry demonstrate a genetic flow of mutations between them. Thus, social structure within an inbred community can be delineated through genomic data, with implications to genetic counseling and genetic mapping. PMID:24084643

  5. Strategy Maps in University Management: A Comparative Study

    ERIC Educational Resources Information Center

    Han, Shuangmiao; Zhong, Zhou

    2015-01-01

    In this study, the conceptual use of the strategy map approach and the strategy map which it produces have been adapted from the business sector and introduced as tools for achieving more effective strategic planning and management in higher education institutions (HEIs). This study discusses the development of strategy maps as transformational…

  6. Testing Central and Inner Asian admixture among contemporary Hungarians.

    PubMed

    Bíró, András; Fehér, Tibor; Bárány, Gusztáv; Pamjav, Horolma

    2015-03-01

    Historically, the Carpathian Basin was the final destination for many nomadic peoples who migrated westward from Inner and Central Asia towards Europe. Proto-Hungarians (Steppe Magyars) were among those who came from the East, the Eurasian Steppe in the early middle ages. In order to detect the paternal genetic contribution from nomadic Steppe tribes, we tested 966 samples from Central Asian (Uzbekistan, Kazakhstan), Inner Asian (Mongolians and Buryats in Mongolia) and Hungarian-speaking European (Hungarian, Sekler and Csango) populations. We constructed median-joining networks of certain haplogroups in Hungarian-speaking European, and Altaic-speaking Central and Inner Asian populations. We estimated that the possible paternal genetic contribution from the above described populations among contemporary Hungarian speaking populations ranged between 5% and 7.4%. It is lowest among Hungarians from Hungary (5.1%), while higher among Hungarian-speaking groups in Romania, notably Sekler (7.4%) and Csango (6.3%). However, these results represent only an upper limit. Actual Central/Inner Asian admixture might be somewhat lower as some of the related lineages may have come from a common third source. The main haplogroups responsible for the Central/Inner Asian admixture among Hungarians are J2*-M172 (xM47, M67, M12), J2-L24, R1a-Z93; Q-M242 and E-M78. Earlier studies showed very limited Uralic genetic influence among Hungarians, and based on the present study, Altaic/Turkic genetic contribution is also not significant, although significantly higher than the Uralic one. The conclusion of this study is that present-day Hungarian speakers are genetically very similar to neighbouring populations, isolated Hungarian speaking groups having relatively higher presence of Central and Inner Asian genetic elements. At the same time, the reliable historical and genetic conclusions require an extension of the study to a significantly larger database with deep haplogroup resolution

  7. Ancestry, admixture and fitness in Colombian genomes

    PubMed Central

    Rishishwar, Lavanya; Conley, Andrew B.; Wigington, Charles H.; Wang, Lu; Valderrama-Aguirre, Augusto; King Jordan, I.

    2015-01-01

    The human dimension of the Columbian Exchange entailed substantial genetic admixture between ancestral source populations from Africa, the Americas and Europe, which had evolved separately for many thousands of years. We sought to address the implications of the creation of admixed American genomes, containing novel allelic combinations, for human health and fitness via analysis of an admixed Colombian population from Medellin. Colombian genomes from Medellin show a wide range of three-way admixture contributions from ancestral source populations. The primary ancestry component for the population is European (average = 74.6%, range = 45.0%–96.7%), followed by Native American (average = 18.1%, range = 2.1%–33.3%) and African (average = 7.3%, range = 0.2%–38.6%). Locus-specific patterns of ancestry were evaluated to search for genomic regions that are enriched across the population for particular ancestry contributions. Adaptive and innate immune system related genes and pathways are particularly over-represented among ancestry-enriched segments, including genes (HLA-B and MAPK10) that are involved in defense against endemic pathogens such as malaria. Genes that encode functions related to skin pigmentation (SCL4A5) and cutaneous glands (EDAR) are also found in regions with anomalous ancestry patterns. These results suggest the possibility that ancestry-specific loci were differentially retained in the modern admixed Colombian population based on their utility in the New World environment. PMID:26197429

  8. Genetic evidence for archaic admixture in Africa.

    PubMed

    Hammer, Michael F; Woerner, August E; Mendez, Fernando L; Watkins, Joseph C; Wall, Jeffrey D

    2011-09-13

    A long-debated question concerns the fate of archaic forms of the genus Homo: did they go extinct without interbreeding with anatomically modern humans, or are their genes present in contemporary populations? This question is typically focused on the genetic contribution of archaic forms outside of Africa. Here we use DNA sequence data gathered from 61 noncoding autosomal regions in a sample of three sub-Saharan African populations (Mandenka, Biaka, and San) to test models of African archaic admixture. We use two complementary approximate-likelihood approaches and a model of human evolution that involves recent population structure, with and without gene flow from an archaic population. Extensive simulation results reject the null model of no admixture and allow us to infer that contemporary African populations contain a small proportion of genetic material (≈ 2%) that introgressed ≈ 35 kya from an archaic population that split from the ancestors of anatomically modern humans ≈ 700 kya. Three candidate regions showing deep haplotype divergence, unusual patterns of linkage disequilibrium, and small basal clade size are identified and the distributions of introgressive haplotypes surveyed in a sample of populations from across sub-Saharan Africa. One candidate locus with an unusual segment of DNA that extends for >31 kb on chromosome 4 seems to have introgressed into modern Africans from a now-extinct taxon that may have lived in central Africa. Taken together our results suggest that polymorphisms present in extant populations introgressed via relatively recent interbreeding with hominin forms that diverged from the ancestors of modern humans in the Lower-Middle Pleistocene.

  9. Efficient moment-based inference of admixture parameters and sources of gene flow.

    PubMed

    Lipson, Mark; Loh, Po-Ru; Levin, Alex; Reich, David; Patterson, Nick; Berger, Bonnie

    2013-08-01

    The recent explosion in available genetic data has led to significant advances in understanding the demographic histories of and relationships among human populations. It is still a challenge, however, to infer reliable parameter values for complicated models involving many populations. Here, we present MixMapper, an efficient, interactive method for constructing phylogenetic trees including admixture events using single nucleotide polymorphism (SNP) genotype data. MixMapper implements a novel two-phase approach to admixture inference using moment statistics, first building an unadmixed scaffold tree and then adding admixed populations by solving systems of equations that express allele frequency divergences in terms of mixture parameters. Importantly, all features of the model, including topology, sources of gene flow, branch lengths, and mixture proportions, are optimized automatically from the data and include estimates of statistical uncertainty. MixMapper also uses a new method to express branch lengths in easily interpretable drift units. We apply MixMapper to recently published data for Human Genome Diversity Cell Line Panel individuals genotyped on a SNP array designed especially for use in population genetics studies, obtaining confident results for 30 populations, 20 of them admixed. Notably, we confirm a signal of ancient admixture in European populations-including previously undetected admixture in Sardinians and Basques-involving a proportion of 20-40% ancient northern Eurasian ancestry.

  10. Genetic Adaptation and Neandertal Admixture Shaped the Immune System of Human Populations.

    PubMed

    Quach, Hélène; Rotival, Maxime; Pothlichet, Julien; Loh, Yong-Hwee Eddie; Dannemann, Michael; Zidane, Nora; Laval, Guillaume; Patin, Etienne; Harmant, Christine; Lopez, Marie; Deschamps, Matthieu; Naffakh, Nadia; Duffy, Darragh; Coen, Anja; Leroux-Roels, Geert; Clément, Frederic; Boland, Anne; Deleuze, Jean-François; Kelso, Janet; Albert, Matthew L; Quintana-Murci, Lluis

    2016-10-20

    Humans differ in the outcome that follows exposure to life-threatening pathogens, yet the extent of population differences in immune responses and their genetic and evolutionary determinants remain undefined. Here, we characterized, using RNA sequencing, the transcriptional response of primary monocytes from Africans and Europeans to bacterial and viral stimuli-ligands activating Toll-like receptor pathways (TLR1/2, TLR4, and TLR7/8) and influenza virus-and mapped expression quantitative trait loci (eQTLs). We identify numerous cis-eQTLs that contribute to the marked differences in immune responses detected within and between populations and a strong trans-eQTL hotspot at TLR1 that decreases expression of pro-inflammatory genes in Europeans only. We find that immune-responsive regulatory variants are enriched in population-specific signals of natural selection and show that admixture with Neandertals introduced regulatory variants into European genomes, affecting preferentially responses to viral challenges. Together, our study uncovers evolutionarily important determinants of differences in host immune responsiveness between human populations.

  11. Used cooking oil as a green chemical admixture in concrete

    NASA Astrophysics Data System (ADS)

    Salmia, B.; Che Muda, Zakaria; Ashraful Alam, Md; Sidek, L. M.; Hidayah, B.

    2013-06-01

    According to National Statistics Approximately 1.35 billion gallons of used oil are generated yearly. With the increasing of the concrete usage, a more cost effective and economic new type of admixtures may give positive impacts on the Malaysian construction building as well as worldwide concrete usage. To objective of this is study is to investigate the effect of used cooking oil in terms of slump test, compressive strength test and rebound hammer. By adding the used cooking oil to the concrete, it increases the slump value from 4% to 72%. And the compressive strength have an increment from 1% to 16.8%. The used cooking oil obtains the optimum contribution to the concrete mix proportion of containing used cooking oil of 1.50% from the cement content. The result of used cooking oil from experimental program of slump value and compressive strength proved that used cooking oil have positive effects on replacement of commercially available superplasticizer.

  12. Migration, genetic markers and race admixture in Curitiba, Brazil.

    PubMed

    Culpi, L; Salzano, F M

    1984-01-01

    1000 Blacks and 1001 Whites from the southern Brazilian city Curitiba were studied in relation to migration patterns, ABO and Rh blood groups, and hemoglobin types. Despite a lower socioeconomic level, Blacks migrated more than Whites. Carriers of abnormal hemoglobin types show about the same degree of mobility as those with normal hemoglobin only. As much as 1/2 of the genes present among the Blacks of this city may be of European origin, while persons classified as White may have from 3 to 19% of African ancestry. The results are in agreement with the history of the community and indicate that the process of race admixture is occurring at a high rate despite the relatively low frequency of individuals showing clear signs of African ancestry (as compared the bulk of the Brazilian populations) in Curitiba.

  13. Case studies: Soil mapping using multiple methods

    NASA Astrophysics Data System (ADS)

    Petersen, Hauke; Wunderlich, Tina; Hagrey, Said A. Al; Rabbel, Wolfgang; Stümpel, Harald

    2010-05-01

    Soil is a non-renewable resource with fundamental functions like filtering (e.g. water), storing (e.g. carbon), transforming (e.g. nutrients) and buffering (e.g. contamination). Degradation of soils is meanwhile not only to scientists a well known fact, also decision makers in politics have accepted this as a serious problem for several environmental aspects. National and international authorities have already worked out preservation and restoration strategies for soil degradation, though it is still work of active research how to put these strategies into real practice. But common to all strategies the description of soil state and dynamics is required as a base step. This includes collecting information from soils with methods ranging from direct soil sampling to remote applications. In an intermediate scale mobile geophysical methods are applied with the advantage of fast working progress but disadvantage of site specific calibration and interpretation issues. In the framework of the iSOIL project we present here some case studies for soil mapping performed using multiple geophysical methods. We will present examples of combined field measurements with EMI-, GPR-, magnetic and gammaspectrometric techniques carried out with the mobile multi-sensor-system of Kiel University (GER). Depending on soil type and actual environmental conditions, different methods show a different quality of information. With application of diverse methods we want to figure out, which methods or combination of methods will give the most reliable information concerning soil state and properties. To investigate the influence of varying material we performed mapping campaigns on field sites with sandy, loamy and loessy soils. Classification of measured or derived attributes show not only the lateral variability but also gives hints to a variation in the vertical distribution of soil material. For all soils of course soil water content can be a critical factor concerning a succesful

  14. Estimating African American admixture proportions by use of population-specific alleles.

    PubMed Central

    Parra, E J; Marcini, A; Akey, J; Martinson, J; Batzer, M A; Cooper, R; Forrester, T; Allison, D B; Deka, R; Ferrell, R E; Shriver, M D

    1998-01-01

    We analyzed the European genetic contribution to 10 populations of African descent in the United States (Maywood, Illinois; Detroit; New York; Philadelphia; Pittsburgh; Baltimore; Charleston, South Carolina; New Orleans; and Houston) and in Jamaica, using nine autosomal DNA markers. These markers either are population-specific or show frequency differences >45% between the parental populations and are thus especially informative for admixture. European genetic ancestry ranged from 6.8% (Jamaica) to 22.5% (New Orleans). The unique utility of these markers is reflected in the low variance associated with these admixture estimates (SEM 1.3%-2.7%). We also estimated the male and female European contribution to African Americans, on the basis of informative mtDNA (haplogroups H and L) and Y Alu polymorphic markers. Results indicate a sex-biased gene flow from Europeans, the male contribution being substantially greater than the female contribution. mtDNA haplogroups analysis shows no evidence of a significant maternal Amerindian contribution to any of the 10 populations. We detected significant nonrandom association between two markers located 22 cM apart (FY-null and AT3), most likely due to admixture linkage disequilibrium created in the interbreeding of the two parental populations. The strength of this association and the substantial genetic distance between FY and AT3 emphasize the importance of admixed populations as a useful resource for mapping traits with different prevalence in two parental populations. PMID:9837836

  15. Learning from Concept Mapping and Hypertext: An Eye Tracking Study

    ERIC Educational Resources Information Center

    Amadieu, Franck; Salmerón, Ladislao; Cegarra, Julien; Paubel, Pierre-Vincent; Lemarié, Julie; Chevalier, Aline

    2015-01-01

    This study examined the effects of prior domain knowledge and learning sequences on learning with concept mapping and hypertext. Participants either made a concept map in a first step and then read the hypertext's contents combined with concept mapping (high activating condition), or they read the hypertext's contents first and then made a concept…

  16. Self-Mapping in Treating Suicide Ideation: A Case Study

    ERIC Educational Resources Information Center

    Robertson, Lloyd Hawkeye

    2011-01-01

    This case study traces the development and use of a self-mapping exercise in the treatment of a youth who had been at risk for re-attempting suicide. A life skills exercise was modified to identify units of culture called "memes" from which a map of the youth's self was prepared. A successful treatment plan followed the mapping exercise. The…

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

    PubMed

    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

    2015-10-05

    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 [1-7]. 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 [8-11]. 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.

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

    PubMed Central

    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

  19. State of the art: regional anesthesia using anesthetic admixtures.

    PubMed

    Fetzer-Fowler, S

    1992-08-01

    Aging, high-risk, and ambulatory patients comprise a growing population of surgical candidates. The advantages of regional anesthesia for these patients has promoted technological and pharmacological advances. As new anesthetic agents are developed, methods to improve existing local anesthetics continue. This article reviews the current practice of local anesthetic admixtures. The physiological action of the local anesthetics and their additives is explained relative to their chemical properties. The advantages and risks when adding bicarbonate and epinephrine are described. Nursing implications for the care of the patient receiving regional anesthesia using admixtures are reviewed. An actual case report is presented to demonstrate the clinical application of local anesthetic admixtures.

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

    PubMed

    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

    2014-10-02

    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.

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

    PubMed Central

    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

  2. Admixture patterns and genetic differentiation in negrito groups from West Malaysia estimated from genome-wide SNP data.

    PubMed

    Jinam, Timothy A; Phipps, Maude E; Saitou, Naruya

    2013-01-01

    Southeast Asia houses various culturally and linguistically diverse ethnic groups. In Malaysia, where the Malay, Chinese, and Indian ethnic groups form the majority, there exist minority groups such as the "negritos" who are believed to be descendants of the earliest settlers of Southeast Asia. Here we report patterns of genetic substructure and admixture in two Malaysian negrito populations (Jehai and Kensiu), using ~50,000 genome-wide single-nucleotide polymorphism (SNP) data. We found traces of recent admixture in both the negrito populations, particularly in the Jehai, with the Malay through principal component analysis and STRUCTURE analysis software, which suggested that the admixture was as recent as one generation ago. We also identified significantly differentiated nonsynonymous SNPs and haplotype blocks related to intracellular transport, metabolic processes, and detection of stimulus. These results highlight the different levels of admixture experienced by the two Malaysian negritos. Delineating admixture and differentiated genomic regions should be of importance in designing and interpretation of molecular anthropology and disease association studies.

  3. Genetic admixture of eight Mexican indigenous populations: based on five polymarker, HLA-DQA1, ABO, and RH loci.

    PubMed

    Buentello-Malo, Leonora; Peñaloza-Espinosa, Rosenda I; Salamanca-Gómez, Fabio; Cerda-Flores, Ricardo M

    2008-01-01

    This study explores the genetic admixture of eight Mexican indigenous populations (Otomi-Ixmiquilpan, Otomi-Actopan, Tzeltales, Nahua-Milpa-Alta, Nahua-Xochimilco, Nahua-Zitlala, Nahua-Ixhuatlancillo, and Nahua-Coyolillo) on the basis of five PCR-based polymorphic DNA loci (LDLR, GYPA, HBGG, D7S8, GC), HLA_DQA1, and the blood groups ABO and Rh (CcDEe). Among the indigenous populations, the highest gene frequencies for O and D were 0.9703 and 1.000 for Zitlala (State of Guerrero) and 0.9955 and 0.9414 for Tzeltales (State of Chiapas), respectively. Maximum likelihood estimates of admixture components yield a trihybrid model with Amerindian (assuming that Nahua-Zitlala is the most representative indigenous population), Spanish, and African ancestry with the admixture proportions: 93.03, 6.03, and 0.94 for Tzeltales, and 28.99, 44.03, and 26.98 for Coyolillo. A contribution of the ancestral populations of Ixhuatlancillo, Actopan, Ixmiquilpan, Milpa-Alta, and Xochimilco were found with the following average of admixture proportions: 75.84, 22.50, and 1.66. The findings herein demonstrate that the genetic admixture of the Mexican indigenous populations who at present speak the same Amer-Indian language can be differentiated and that the majority of them have less ancestral indigenous contribution than those considered as Mestizo populations.

  4. Identifying environmental sounds: a multimodal mapping study

    PubMed Central

    Tomasino, Barbara; Canderan, Cinzia; Marin, Dario; Maieron, Marta; Gremese, Michele; D'Agostini, Serena; Fabbro, Franco; Skrap, Miran

    2015-01-01

    Our environment is full of auditory events such as warnings or hazards, and their correct recognition is essential. We explored environmental sounds (ES) recognition in a series of studies. In study 1 we performed an Activation Likelihood Estimation (ALE) meta-analysis of neuroimaging experiments addressing ES processing to delineate the network of areas consistently involved in ES processing. Areas consistently activated in the ALE meta-analysis were the STG/MTG, insula/rolandic operculum, parahippocampal gyrus and inferior frontal gyrus bilaterally. Some of these areas truly reflect ES processing, whereas others are related to design choices, e.g., type of task, type of control condition, type of stimulus. In study 2 we report on 7 neurosurgical patients with lesions involving the areas which were found to be activated by the ALE meta-analysis. We tested their ES recognition abilities and found an impairment of ES recognition. These results indicate that deficits of ES recognition do not exclusively reflect lesions to the right or to the left hemisphere but both hemispheres are involved. The most frequently lesioned area is the hippocampus/insula/STG. We made sure that any impairment in ES recognition would not be related to language problems, but reflect impaired ES processing. In study 3 we carried out an fMRI study on patients (vs. healthy controls) to investigate how the areas involved in ES might be functionally deregulated because of a lesion. The fMRI evidenced that controls activated the right IFG, the STG bilaterally and the left insula. We applied a multimodal mapping approach and found that, although the meta-analysis showed that part of the left and right STG/MTG activation during ES processing might in part be related to design choices, this area was one of the most frequently lesioned areas in our patients, thus highlighting its causal role in ES processing. We found that the ROIs we drew on the two clusters of activation found in the left and in

  5. A new world natural vegetation map for global change studies.

    PubMed

    Lapola, David M; Oyama, Marcos D; Nobre, Carlos A; Sampaio, Gilvan

    2008-06-01

    We developed a new world natural vegetation map at 1 degree horizontal resolution for use in global climate models. We used the Dorman and Sellers vegetation classification with inclusion of a new biome: tropical seasonal forest, which refers to both deciduous and semi-deciduous tropical forests. SSiB biogeophysical parameters values for this new biome type are presented. Under this new vegetation classification we obtained a consensus map between two global natural vegetation maps widely used in climate studies. We found that these two maps assign different biomes in ca. 1/3 of the continental grid points. To obtain a new global natural vegetation map, non-consensus areas were filled according to regional consensus based on more than 100 regional maps available on the internet. To minimize the risk of using poor quality information, the regional maps were obtained from reliable internet sources, and the filling procedure was based on the consensus among several regional maps obtained from independent sources. The new map was designed to reproduce accurately both the large-scale distribution of the main vegetation types (as it builds on two reliable global natural vegetation maps) and the regional details (as it is based on the consensus of regional maps).

  6. Studying Participants' Experiences Using Concept Mapping.

    ERIC Educational Resources Information Center

    Truscott, Derek; Paulson, Barbara L.; Everall, Robin D.

    1999-01-01

    Concept mapping is a participant-based methodology that involves three processes: participant generation of ideas or experiences about a specific question, grouping together responses through an unstructured card sort by participants, and statistical analysis of card-sort results using multidimensional scaling and cluster analysis. A research…

  7. The origin of early age expansions induced in cementitious materials containing shrinkage reducing admixtures

    SciTech Connect

    Sant, Gaurav; Lothenbach, Barbara; Juilland, Patrick; Le Saout, Gwenn; Weiss, Jason; Scrivener, Karen

    2011-03-15

    Studies on the early-age shrinkage behavior of cement pastes, mortars, and concretes containing shrinkage reducing admixtures (SRAs) have indicated these mixtures frequently exhibit an expansion shortly after setting. While the magnitude of the expansion has been noted to be a function of the chemistry of the cement and the admixture dosage; the cause of the expansion is not clearly understood. This investigation uses measurements of autogenous deformation, X-ray diffraction, pore solution analysis, thermogravimetry, and scanning electron microscopy to study the early-age properties and describe the mechanism of the expansion in OPC pastes made with and without SRA. The composition of the pore solution indicates that the presence of the SRA increases the portlandite oversaturation level in solution which can result in higher crystallization stresses which could lead to an expansion. This observation is supported by deformation calculations for the systems examined.

  8. Mapping asthma-associated variants in admixed populations

    PubMed Central

    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 identify genomic regions where an association exists between genetic ancestry and asthma (in contrast to between the genotype of the marker and asthma). The theory behind AM is that chromosomal segments of affected individuals contain a significantly higher-than-average proportion of alleles from the high-risk parental population and thus are more likely to harbor disease–associated loci. Criteria to evaluate the applicability of AM as a gene mapping approach include: (1) the prevalence of the disease differences in ancestral populations from which the admixed population was formed; (2) a measurable difference in disease-causing alleles between the parental populations; (3) reduced linkage disequilibrium (LD) between unlinked loci across chromosomes and strong LD between neighboring loci; (4) a set of markers with noticeable allele-frequency differences between parental populations that contributes to the admixed population (single nucleotide polymorphisms (SNPs) are the markers of choice because they are abundant, stable, relatively cheap to genotype, and informative with regard to the LD structure of chromosomal segments); and (5) there is an understanding of the extent of segmental chromosomal admixtures and their interactions with environmental factors. Although genome-wide association studies have contributed greatly to our understanding of the genetic components of asthma, the large and increasing degree of admixture in populations across the world create many challenges

  9. Worldwide Patterns of Ancestry, Divergence, and Admixture in Domesticated Cattle

    PubMed Central

    Decker, Jared E.; McKay, Stephanie D.; Rolf, Megan M.; Kim, JaeWoo; Molina Alcalá, Antonio; Sonstegard, Tad S.; Hanotte, Olivier; Götherström, Anders; Seabury, Christopher M.; Praharani, Lisa; Babar, Masroor Ellahi; Correia de Almeida Regitano, Luciana; Yildiz, Mehmet Ali; Heaton, Michael P.; Liu, Wan-Sheng; Lei, Chu-Zhao; Reecy, James M.; Saif-Ur-Rehman, Muhammad; Schnabel, Robert D.; Taylor, Jeremy F.

    2014-01-01

    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. PMID:24675901

  10. Human-aided admixture may fuel ecosystem transformation during biological invasions: theoretical and experimental evidence.

    PubMed

    Molofsky, Jane; Keller, Stephen R; Lavergne, Sébastien; Kaproth, Matthew A; Eppinga, Maarten B

    2014-04-01

    Biological invasions can transform our understanding of how the interplay of historical isolation and contemporary (human-aided) dispersal affects the structure of intraspecific diversity in functional traits, and in turn, how changes in functional traits affect other scales of biological organization such as communities and ecosystems. Because biological invasions frequently involve the admixture of previously isolated lineages as a result of human-aided dispersal, studies of invasive populations can reveal how admixture results in novel genotypes and shifts in functional trait variation within populations. Further, because invasive species can be ecosystem engineers within invaded ecosystems, admixture-induced shifts in the functional traits of invaders can affect the composition of native biodiversity and alter the flow of resources through the system. Thus, invasions represent promising yet under-investigated examples of how the effects of short-term evolutionary changes can cascade across biological scales of diversity. Here, we propose a conceptual framework that admixture between divergent source populations during biological invasions can reorganize the genetic variation underlying key functional traits, leading to shifts in the mean and variance of functional traits within invasive populations. Changes in the mean or variance of key traits can initiate new ecological feedback mechanisms that result in a critical transition from a native ecosystem to a novel invasive ecosystem. We illustrate the application of this framework with reference to a well-studied plant model system in invasion biology and show how a combination of quantitative genetic experiments, functional trait studies, whole ecosystem field studies and modeling can be used to explore the dynamics predicted to trigger these critical transitions.

  11. What causes birth order-intelligence patterns? The admixture hypothesis, revived.

    PubMed

    Rodgers, J L

    2001-01-01

    Recent evidence shows that the relation between birth order and intelligence is not the same in cross-sectional and within-family data. This simple empirical observation invalidates the conclusions from hundreds of previous birth order studies that relied on cross-sectional data. Simultaneously, the empirical foundation disappears from underneath theories like dilution and the confluence model that use explanatory processes occurring within the family. A theory proposed almost 25 years ago--the admixture hypothesis--effectively accounts for these empirical patterns. In this article, the author describes why birth order is of such intense interest to both parents and researchers (the birth order trap), discusses past birth order-intelligence patterns, shows that the admixture hypothesis accounts for those patterns, and reframes the original argument to support future productive research efforts.

  12. Testing for Ancient Admixture between Closely Related Populations

    PubMed Central

    Durand, Eric Y.; Patterson, Nick; Reich, David; Slatkin, Montgomery

    2011-01-01

    One enduring question in evolutionary biology is the extent of archaic admixture in the genomes of present-day populations. In this paper, we present a test for ancient admixture that exploits the asymmetry in the frequencies of the two nonconcordant gene trees in a three-population tree. This test was first applied to detect interbreeding between Neandertals and modern humans. We derive the analytic expectation of a test statistic, called the D statistic, which is sensitive to asymmetry under alternative demographic scenarios. We show that the D statistic is insensitive to some demographic assumptions such as ancestral population sizes and requires only the assumption that the ancestral populations were randomly mating. An important aspect of D statistics is that they can be used to detect archaic admixture even when no archaic sample is available. We explore the effect of sequencing error on the false-positive rate of the test for admixture, and we show how to estimate the proportion of archaic ancestry in the genomes of present-day populations. We also investigate a model of subdivision in ancestral populations that can result in D statistics that indicate recent admixture. PMID:21325092

  13. Mapping Climate Change: Six U.S. Case Studies

    ERIC Educational Resources Information Center

    Holmberg, Marjorie O.

    2010-01-01

    This research focuses on the current role of mapping practices in communicating climate change in the United States. This includes maps used in monitoring climate change, projecting its potential impacts, and identifying potential adaptation strategies at particular scales. Since few, if any, studies have been done specifically on mapping…

  14. Connecticut Curriculum Trace Maps: History/Social Studies.

    ERIC Educational Resources Information Center

    Connecticut State Board of Education, Hartford.

    These Connecticut Curriculum Trace Maps are designed to help curriculum developers and teachers translate Connecticut's K-12 history and social studies performance standards into objectives and classroom practice. The Trace Maps provide detailed descriptions of what students should know and be able to do at smaller grade level clusters, K-2, 3-4,…

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

    PubMed Central

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

    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: Austronesian (17%–62%), Proto-Malay (15%–31%), East Asian (4%–16%) and South Asian (3%–34%). Approximately 34% of the genetic makeup of SLM is of South Asian ancestry, resulting in its distinct genetic pattern compared with the other three Malay populations. Besides, substantial differentiation was observed between the Malay populations from the north and the south, and between those from the west and the east. In summary, this study revealed that the genetic identity of the Malays comprises a mixed entity of multiple ancestries represented by Austronesian, Proto-Malay, East Asian and South Asian, with most of the admixture events estimated to have occurred 175 to 1,500 years ago, which in turn suggests that geographical isolation and independent admixture have significantly shaped the genetic architectures and the diversity of the Malay populations. PMID:26395220

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

    PubMed

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

    2015-09-23

    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: Austronesian (17%-62%), Proto-Malay (15%-31%), East Asian (4%-16%) and South Asian (3%-34%). Approximately 34% of the genetic makeup of SLM is of South Asian ancestry, resulting in its distinct genetic pattern compared with the other three Malay populations. Besides, substantial differentiation was observed between the Malay populations from the north and the south, and between those from the west and the east. In summary, this study revealed that the genetic identity of the Malays comprises a mixed entity of multiple ancestries represented by Austronesian, Proto-Malay, East Asian and South Asian, with most of the admixture events estimated to have occurred 175 to 1,500 years ago, which in turn suggests that geographical isolation and independent admixture have significantly shaped the genetic architectures and the diversity of the Malay populations.

  17. Performance Mapping Studies in Redox Flow Cells

    NASA Technical Reports Server (NTRS)

    Hoberecht, M. A.; Thaller, L. H.

    1981-01-01

    Pumping power requirements in any flow battery system constitute a direct parasitic energy loss. It is therefore useful to determine the practical lower limit for reactant flow rates. Through the use of a theoretical framework based on electrochemical first principles, two different experimental flow mapping techniques were developed to evaluate and compare electrodes as a function of flow rate. For the carbon felt electrodes presently used in NASA-Lewis Redox cells, a flow rate 1.5 times greater than the stoichiometric rate seems to be the required minimum.

  18. Uncontrolled admixture and loss of genetic diversity in a local Vietnamese pig breed.

    PubMed

    Berthouly-Salazar, Cécile; Thévenon, Sophie; Van, Thu Nhu; Nguyen, Binh Trong; Pham, Lan Doan; Chi, Cuong Vu; Maillard, Jean-Charles

    2012-05-01

    The expansion of intensive livestock production systems in developing countries has increased the introduction of highly productive exotic breeds facilitating indiscriminate crossbreeding with local breeds. In this study, we set out to investigate the genetic status of the Vietnamese Black H'mong pig breed by evaluating (1) genetic diversity and (2) introgression from exotic breeds. Two exotic breeds, namely Landrace and Yorkshire used for crossbreeding, and the H'mong pig population from Ha Giang (HG) province were investigated using microsatellite markers. Within the province, three phenotypes were observed: a White, a Spotted and a Black phenotype. Genetic differentiation between phenotypes was low (0.5-6.1%). The White phenotypes showed intermediate admixture values between exotic breeds and the Black HG population (0.53), indicating a crossbreed status. Management practices were used to predict the rate of private diversity loss due to exotic gene introgressions. After 60 generations, 100% of Black private alleles will be lost. This loss is accelerated if the admixture rate is increased but can be slowed down if the mortality rate (e.g., recruitment rate) is decreased. Our study showed that a large number of markers are needed for accurately identifying hybrid classes for closely related populations. While our estimate of admixture still seems underestimated, genetic erosion can occur very fast even through indiscriminate crossbreeding.

  19. Uncontrolled admixture and loss of genetic diversity in a local Vietnamese pig breed

    PubMed Central

    Berthouly-Salazar, Cécile; Thévenon, Sophie; Van, Thu Nhu; Nguyen, Binh Trong; Pham, Lan Doan; Chi, Cuong Vu; Maillard, Jean-Charles

    2012-01-01

    The expansion of intensive livestock production systems in developing countries has increased the introduction of highly productive exotic breeds facilitating indiscriminate crossbreeding with local breeds. In this study, we set out to investigate the genetic status of the Vietnamese Black H’mong pig breed by evaluating (1) genetic diversity and (2) introgression from exotic breeds. Two exotic breeds, namely Landrace and Yorkshire used for crossbreeding, and the H’mong pig population from Ha Giang (HG) province were investigated using microsatellite markers. Within the province, three phenotypes were observed: a White, a Spotted and a Black phenotype. Genetic differentiation between phenotypes was low (0.5–6.1%). The White phenotypes showed intermediate admixture values between exotic breeds and the Black HG population (0.53), indicating a crossbreed status. Management practices were used to predict the rate of private diversity loss due to exotic gene introgressions. After 60 generations, 100% of Black private alleles will be lost. This loss is accelerated if the admixture rate is increased but can be slowed down if the mortality rate (e.g., recruitment rate) is decreased. Our study showed that a large number of markers are needed for accurately identifying hybrid classes for closely related populations. While our estimate of admixture still seems underestimated, genetic erosion can occur very fast even through indiscriminate crossbreeding. PMID:22837841

  20. Strong Selection at MHC in Mexicans since Admixture

    PubMed Central

    Zhou, Quan; Zhao, Liang; Guan, Yongtao

    2016-01-01

    Mexicans are a recent admixture of Amerindians, Europeans, and Africans. We performed local ancestry analysis of Mexican samples from two genome-wide association studies obtained from dbGaP, and discovered that at the MHC region Mexicans have excessive African ancestral alleles compared to the rest of the genome, which is the hallmark of recent selection for admixed samples. The estimated selection coefficients are 0.05 and 0.07 for two datasets, which put our finding among the strongest known selections observed in humans, namely, lactase selection in northern Europeans and sickle-cell trait in Africans. Using inaccurate Amerindian training samples was a major concern for the credibility of previously reported selection signals in Latinos. Taking advantage of the flexibility of our statistical model, we devised a model fitting technique that can learn Amerindian ancestral haplotype from the admixed samples, which allows us to infer local ancestries for Mexicans using only European and African training samples. The strong selection signal at the MHC remains without Amerindian training samples. Finally, we note that medical history studies suggest such a strong selection at MHC is plausible in Mexicans. PMID:26863142

  1. Spanish genetic admixture is associated with larger V(O2) max decrement from sea level to 4338 m in Peruvian Quechua.

    PubMed

    Brutsaert, Tom D; Parra, Esteban J; Shriver, Mark D; Gamboa, Alfredo; Palacios, Jose-Antonio; Rivera, Maria; Rodriguez, Ivette; León-Velarde, Fabiola

    2003-08-01

    Quechua in the Andes may be genetically adapted to altitude and able to resist decrements in maximal O2 consumption in hypoxia (DeltaVo2 max). This hypothesis was tested via repeated measures of Vo2 max (sea level vs. 4338 m) in 30 men of mixed Spanish and Quechua origins. Individual genetic admixture level (%Spanish ancestry) was estimated by using ancestry-informative DNA markers. Genetic admixture explained a significant proportion of the variability in DeltaVo2 max after control for covariate effects, including sea level Vo2 max and the decrement in arterial O2 saturation measured at Vo2 max (DeltaSpO2 max) (R2 for admixture and covariate effects approximately 0.80). The genetic effect reflected a main effect of admixture on DeltaVo2 max (P = 0.041) and an interaction between admixture and DeltaSpO2 max (P = 0.018). Admixture predicted DeltaVo2 max only in subjects with a large DeltaSpO2 max (P = 0.031). In such subjects, DeltaVo2 max was 12-18% larger in a subgroup of subjects with high vs. low Spanish ancestry, with least squares mean values (+/-SE) of 739 +/- 71 vs. 606 +/- 68 ml/min, respectively. A trend for interaction (P = 0.095) was also noted between admixture and the decrease in ventilatory threshold at 4338 m. As previously, admixture predicted DeltaVo2 max only in subjects with a large decrease in ventilatory threshold. These findings suggest that the genetic effect on DeltaVo2 max depends on a subject's aerobic fitness. Genetic effects may be more important (or easier to detect) in athletic subjects who are more likely to show gas-exchange impairment during exercise. The results of this study are consistent with the evolutionary hypothesis and point to a better gas-exchange system in Quechua.

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

    PubMed

    González-Ruiz, Mercedes; Santos, Cristina; Jordana, Xavier; Simón, Marc; Lalueza-Fox, Carles; Gigli, Elena; Aluja, Maria Pilar; Malgosa, Assumpció

    2012-01-01

    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.

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

    PubMed

    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.

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

    PubMed Central

    Legault, Michel

    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

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

    PubMed

    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.

  6. Environment-dependent admixture dynamics in a tiger salamander hybrid zone.

    PubMed

    Fitzpatrick, Benjamin M; Shaffer, H Bradley

    2004-06-01

    After an estimated five million years of independent evolution, the barred tiger salamander (Ambystoma tigrinum mavortium) was introduced by bait dealers into the native range of the California tiger salamander (A. californiense). Hybridization and backcrossing have been occurring in central California for 50-60 years, or an estimated 15-30 generations. We studied genetic and ecological factors influencing admixture of these two divergent gene pools by analyzing frequencies of hybrid genotypes in three kinds of breeding habitats: natural vernal pools, ephemeral man-made cattle ponds, and perennial man-made ponds. Perennial ponds tended to have higher frequencies of nonnative alleles than either type of seasonal pond, even in cases where perennial and seasonal ponds are within a few hundred meters. Thus, the hybrid zone has a mosaic structure that depends on pond hydrology or ecology. The presence of some broadly acting constraints on admixture is suggested by linkage disequilibria between physically unlinked molecular markers within ponds. In addition, we found several marker-specific deviations from Hardy-Weinberg equilibrium. One marker showed a consistent deficit of heterozygotes across pond types. Another showed heterozygote deficits only in vernal pools. A third was more likely to have heterozygote excess in ephemeral cattle ponds. These patterns indicate that admixture is influenced by complex genotype-by-environment interactions.

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

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

  9. Admixture into and within sub-Saharan Africa.

    PubMed

    Busby, George Bj; Band, Gavin; Si Le, Quang; Jallow, Muminatou; Bougama, Edith; Mangano, Valentina D; Amenga-Etego, Lucas N; Enimil, Anthony; Apinjoh, Tobias; Ndila, Carolyne M; Manjurano, Alphaxard; Nyirongo, Vysaul; Doumba, Ogobara; Rockett, Kirk A; Kwiatkowski, Dominic P; Spencer, Chris Ca

    2016-06-21

    Similarity between two individuals in the combination of genetic markers along their chromosomes indicates shared ancestry and can be used to identify historical connections between different population groups due to admixture. We use a genome-wide, haplotype-based, analysis to characterise the structure of genetic diversity and gene-flow in a collection of 48 sub-Saharan African groups. We show that coastal populations experienced an influx of Eurasian haplotypes over the last 7000 years, and that Eastern and Southern Niger-Congo speaking groups share ancestry with Central West Africans as a result of recent population expansions. In fact, most sub-Saharan populations share ancestry with groups from outside of their current geographic region as a result of gene-flow within the last 4000 years. Our in-depth analysis provides insight into haplotype sharing across different ethno-linguistic groups and the recent movement of alleles into new environments, both of which are relevant to studies of genetic epidemiology.

  10. Estimating individual admixture proportions from next generation sequencing data.

    PubMed

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

    2013-11-01

    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 demonstrate that applying existing methods to genotypes called from the same data can introduce severe biases. The presented method is implemented in the NGSadmix software available at http://www.popgen.dk/software.

  11. Admixture into and within sub-Saharan Africa

    PubMed Central

    Busby, George BJ; Band, Gavin; Si Le, Quang; Jallow, Muminatou; Bougama, Edith; Mangano, Valentina D; Amenga-Etego, Lucas N; Enimil, Anthony; Apinjoh, Tobias; Ndila, Carolyne M; Manjurano, Alphaxard; Nyirongo, Vysaul; Doumba, Ogobara; Rockett, Kirk A; Kwiatkowski, Dominic P; Spencer, Chris CA

    2016-01-01

    Similarity between two individuals in the combination of genetic markers along their chromosomes indicates shared ancestry and can be used to identify historical connections between different population groups due to admixture. We use a genome-wide, haplotype-based, analysis to characterise the structure of genetic diversity and gene-flow in a collection of 48 sub-Saharan African groups. We show that coastal populations experienced an influx of Eurasian haplotypes over the last 7000 years, and that Eastern and Southern Niger-Congo speaking groups share ancestry with Central West Africans as a result of recent population expansions. In fact, most sub-Saharan populations share ancestry with groups from outside of their current geographic region as a result of gene-flow within the last 4000 years. Our in-depth analysis provides insight into haplotype sharing across different ethno-linguistic groups and the recent movement of alleles into new environments, both of which are relevant to studies of genetic epidemiology. DOI: http://dx.doi.org/10.7554/eLife.15266.001 PMID:27324836

  12. Testing models of speciation from genome sequences: divergence and asymmetric admixture in Island South-East Asian Sus species during the Plio-Pleistocene climatic fluctuations

    PubMed Central

    Frantz, Laurent A F; Madsen, Ole; Megens, Hendrik-Jan; Groenen, Martien A M; Lohse, Konrad

    2014-01-01

    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

  13. Islands of biogeodiversity in arid lands on a polygons map study: Detecting scale invariance patterns from natural resources maps.

    PubMed

    Ibáñez, J J; Pérez-Gómez, R; Brevik, Eric C; Cerdà, A

    2016-12-15

    Many maps (geology, hydrology, soil, vegetation, etc.) are created to inventory natural resources. Each of these resources is mapped using a unique set of criteria, including scales and taxonomies. Past research indicates that comparing results of related maps (e.g., soil and geology maps) may aid in identifying mapping deficiencies. Therefore, this study was undertaken in Almeria Province, Spain to (i) compare the underlying map structures of soil and vegetation maps and (ii) investigate if a vegetation map can provide useful soil information that was not shown on a soil map. Soil and vegetation maps were imported into ArcGIS 10.1 for spatial analysis, and results then exported to Microsoft Excel worksheets for statistical analyses to evaluate fits to linear and power law regression models. Vegetative units were grouped according to the driving forces that determined their presence or absence: (i) climatophilous (ii) lithologic-climate; and (iii) edaphophylous. The rank abundance plots for both the soil and vegetation maps conformed to Willis or Hollow Curves, meaning the underlying structures of both maps were the same. Edaphophylous map units, which represent 58.5% of the vegetation units in the study area, did not show a good correlation with the soil map. Further investigation revealed that 87% of the edaphohygrophilous units were found in ramblas, ephemeral riverbeds that are not typically classified and mapped as soils in modern systems, even though they meet the definition of soil given by the most commonly used and most modern soil taxonomic systems. Furthermore, these edaphophylous map units tend to be islands of biodiversity that are threatened by anthropogenic activity in the region. Therefore, this study revealed areas that need to be revisited and studied pedologically. The vegetation mapped in these areas and the soils that support it are key components of the earth's critical zone that must be studied, understood, and preserved.

  14. Length Distribution of Ancestral Tracks under a General Admixture Model and Its Applications in Population History Inference.

    PubMed

    Ni, Xumin; Yang, Xiong; Guo, Wei; Yuan, Kai; Zhou, Ying; Ma, Zhiming; Xu, Shuhua

    2016-01-28

    The length of ancestral tracks decays with the passing of generations which can be used to infer population admixture histories. Previous studies have shown the power in recovering the histories of admixed populations via the length distributions of ancestral tracks even under simple models. We believe that the deduction of length distributions under a general model will greatly elevate the power. Here we first deduced the length distributions under a general model and proposed general principles in parameter estimation and model selection with the deduced length distributions. Next, we focused on studying the length distributions and its applications under three typical special cases. Extensive simulations showed that the length distributions of ancestral tracks were well predicted by our theoretical framework. We further developed a new method, AdmixInfer, based on the length distributions and good performance was observed when it was applied to infer population histories under the three typical models. Notably, our method was insensitive to demographic history, sample size and threshold to discard short tracks. Finally, good performance was also observed when applied to some real datasets of African Americans, Mexicans and South Asian populations from the HapMap project and the Human Genome Diversity Project.

  15. Population admixture and high larval viability among urban toads

    PubMed Central

    Hase, Kazuko; Nikoh, Naruo; Shimada, Masakazu

    2013-01-01

    In terms of evolutionary biology, a population admixture of more than two distinct lineages may lead to strengthened genetic variation through hybridization. However, a population admixture arising from artificial secondary contact poses significant problems in conservation biology. In urban Tokyo, a population admixture has emerged from two lineages of Japanese common toad: native Bufo japonicus formosus and nonnative B. japonicus japonicus, of which the latter was introduced in the early 20th century. To evaluate the degree of genetic disturbance in the admixed population of these two subspecies, we analyzed genotypes of toads distributed within and outside Tokyo by assessing mtDNA and seven microsatellite loci. We found that the introduced B. japonicus japonicus genotype dominates six local populations in the Tokyo admixture zone and was clearly derived from past introgressive hybridization between the two subspecies. These observations were supported by morphological assessments. Furthermore, the average larval survival rate in Tokyo was significantly higher than that outside Tokyo, suggesting that the temporary contribution of introduced toads occurred through introgression. The fitness of toads in urban Tokyo may thus be increasing with the assistance of nonnative individuals. PMID:23789077

  16. Premixed intravenous admixtures: a positive development for hospital pharmacy.

    PubMed

    Lee, H E

    1983-06-01

    The development of premixed intravenous admixtures is reviewed in a historical context, and its effects on hospital pharmacy practice are discussed. As pharmaceutical manufacturers introduce more i.v. medications in ready-to-use containers, the same complaints that were voiced by pharmacists about unit dose packaging and ready-to-dispense tablets and capsules are being aired. But premixed i.v. admixtures are a logical extension of the basic unit dose principle of providing a readily identifiable and ready-to-administer dose. The time and cost savings these products offer are needed in hospital pharmacies. Some of the disadvantages of these products--including storage and freezer space and multiplicity of administration systems--are overcome by proper planning and education of personnel. If fewer personnel are now needed to prepare i.v. admixtures, then those personnel should be used to improve patient care in other ways. The use of premixed i.v. admixtures is a positive technological advance in drug packaging. Its advantages outweight its disadvantages, and it will soon be become the universally accepted form of i.v. drug packaging.

  17. Investigation of Proprietary Admixtures. Report 2. 1977-1978 Tests.

    DTIC Science & Technology

    1980-01-01

    proprietary admixtures obtained for this investigation were described as follows: a. SM-10-77 is a condensation product of melamine and formaldehyde . b. SM-1...78 is a sulfonated naphthalene formaldehyde condensate. c. SM-5-79 is an aqueous solution of a modified naphthalene sulfonate . Mixtures 9. Air

  18. Microbiologic quality assurance for intravenous admixtures in a small hospital.

    PubMed

    Doss, H L; James, J D; Killough, D M; Snodgrass, G L

    1982-05-01

    A simple, inexpensive method for end-product testing of intravenous admixtures for microbial contamination was developed and tested by challenging the system with low levels of microbial contamination. The 16-step procedure for testing i.v. admixtures for microbial contamination used total-sample membrane filtration A 0.2-micrometers Nalgene filter unit was used; the entire contents of randomly selected admixtures were to be filtered and discarded under the procedure. Filters were incubated on sheep-blood agar plates for 48 hours at 35 degrees C. Low concentrations (Klebsiella pneumoniae and Pseudomonas aeruginosa were used to contaminate admixtures deliberately to challenge the system. Seventy-two solutions were contaminated with each microbe; 72 other solutions were inoculated with sterile 0.9% sodium chloride; and 72 uninoculated solutions served as controls. Filtration was performed on a laboratory bench to prevent contamination of the laminar-flow hood. In deliberately contaminated solutions, a mean of 82% of inoculated organisms was isolated by membrane filtration. Five instances of adventitious contamination were noted among the 288 samples; these occurred across all experimental groups. Cost per sample was $4-5. This system can be used by hospital pharmacists to produce documentation of quality assurance that will be acceptable in terms of cost, simplicity, and accuracy.

  19. Implications of the Admixture Process in Skin Color Molecular Assessment

    PubMed Central

    de Cerqueira, Caio Cesar Silva; Hünemeier, Tábita; Gomez-Valdés, Jorge; Ramallo, Virgínia; Volasko-Krause, Carla Daiana; Barbosa, Ana Angélica Leal; Vargas-Pinilla, Pedro; Dornelles, Rodrigo Ciconet; Longo, Danaê; Rothhammer, Francisco; Bedoya, Gabriel; Canizales-Quinteros, Samuel; Acuña-Alonzo, Victor; Gallo, Carla; Poletti, Giovanni; González-José, Rolando; Salzano, Francisco Mauro; Callegari-Jacques, Sídia Maria; Schuler-Faccini, Lavínia; Ruiz-Linares, Andrés; Cátira Bortolini, Maria

    2014-01-01

    The understanding of the complex genotype-phenotype architecture of human pigmentation has clear implications for the evolutionary history of humans, as well as for medical and forensic practices. Although dozens of genes have previously been associated with human skin color, knowledge about this trait remains incomplete. In particular, studies focusing on populations outside the European-North American axis are rare, and, until now, admixed populations have seldom been considered. The present study was designed to help fill this gap. Our objective was to evaluate possible associations of 18 single nucleotide polymorphisms (SNPs), located within nine genes, and one pseudogene with the Melanin Index (MI) in two admixed Brazilian populations (Gaucho, N = 352; Baiano, N = 148) with different histories of geographic and ethnic colonization. Of the total sample, four markers were found to be significantly associated with skin color, but only two (SLC24A5 rs1426654, and SLC45A2 rs16891982) were consistently associated with MI in both samples (Gaucho and Baiano). Therefore, only these 2 SNPs should be preliminarily considered to have forensic significance because they consistently showed the association independently of the admixture level of the populations studied. We do not discard that the other two markers (HERC2 rs1129038 and TYR rs1126809) might be also relevant to admixed samples, but additional studies are necessary to confirm the real importance of these markers for skin pigmentation. Finally, our study shows associations of some SNPs with MI in a modern Brazilian admixed sample, with possible applications in forensic genetics. Some classical genetic markers in Euro-North American populations are not associated with MI in our sample. Our results point out the relevance of considering population differences in selecting an appropriate set of SNPs as phenotype predictors in forensic practice. PMID:24809478

  20. Implications of the admixture process in skin color molecular assessment.

    PubMed

    Cerqueira, Caio Cesar Silva de; Hünemeier, Tábita; Gomez-Valdés, Jorge; Ramallo, Virgínia; Volasko-Krause, Carla Daiana; Barbosa, Ana Angélica Leal; Vargas-Pinilla, Pedro; Dornelles, Rodrigo Ciconet; Longo, Danaê; Rothhammer, Francisco; Bedoya, Gabriel; Canizales-Quinteros, Samuel; Acuña-Alonzo, Victor; Gallo, Carla; Poletti, Giovanni; González-José, Rolando; Salzano, Francisco Mauro; Callegari-Jacques, Sídia Maria; Schuler-Faccini, Lavínia; Ruiz-Linares, Andrés; Cátira Bortolini, Maria

    2014-01-01

    The understanding of the complex genotype-phenotype architecture of human pigmentation has clear implications for the evolutionary history of humans, as well as for medical and forensic practices. Although dozens of genes have previously been associated with human skin color, knowledge about this trait remains incomplete. In particular, studies focusing on populations outside the European-North American axis are rare, and, until now, admixed populations have seldom been considered. The present study was designed to help fill this gap. Our objective was to evaluate possible associations of 18 single nucleotide polymorphisms (SNPs), located within nine genes, and one pseudogene with the Melanin Index (MI) in two admixed Brazilian populations (Gaucho, N = 352; Baiano, N = 148) with different histories of geographic and ethnic colonization. Of the total sample, four markers were found to be significantly associated with skin color, but only two (SLC24A5 rs1426654, and SLC45A2 rs16891982) were consistently associated with MI in both samples (Gaucho and Baiano). Therefore, only these 2 SNPs should be preliminarily considered to have forensic significance because they consistently showed the association independently of the admixture level of the populations studied. We do not discard that the other two markers (HERC2 rs1129038 and TYR rs1126809) might be also relevant to admixed samples, but additional studies are necessary to confirm the real importance of these markers for skin pigmentation. Finally, our study shows associations of some SNPs with MI in a modern Brazilian admixed sample, with possible applications in forensic genetics. Some classical genetic markers in Euro-North American populations are not associated with MI in our sample. Our results point out the relevance of considering population differences in selecting an appropriate set of SNPs as phenotype predictors in forensic practice.

  1. Secondary Contact and Admixture between Independently Invading Populations of the Western Corn Rootworm, Diabrotica virgifera virgifera in Europe

    PubMed Central

    Bermond, Gérald; Ciosi, Marc; Lombaert, Eric; Blin, Aurélie; Boriani, Marco; Furlan, Lorenzo; Toepfer, Stefan; Guillemaud, Thomas

    2012-01-01

    The western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), is one of the most destructive pests of corn in North America and is currently invading Europe. The two major invasive outbreaks of rootworm in Europe have occurred, in North-West Italy and in Central and South-Eastern Europe. These two outbreaks originated from independent introductions from North America. Secondary contact probably occurred in North Italy between these two outbreaks, in 2008. We used 13 microsatellite markers to conduct a population genetics study, to demonstrate that this geographic contact resulted in a zone of admixture in the Italian region of Veneto. We show that i) genetic variation is greater in the contact zone than in the parental outbreaks; ii) several signs of admixture were detected in some Venetian samples, in a Bayesian analysis of the population structure and in an approximate Bayesian computation analysis of historical scenarios and, finally, iii) allelic frequency clines were observed at microsatellite loci. The contact between the invasive outbreaks in North-West Italy and Central and South-Eastern Europe resulted in a zone of admixture, with particular characteristics. The evolutionary implications of the existence of a zone of admixture in Northern Italy and their possible impact on the invasion success of the western corn rootworm are discussed. PMID:23189184

  2. Secondary contact and admixture between independently invading populations of the western corn rootworm, Diabrotica virgifera virgifera in Europe.

    PubMed

    Bermond, Gérald; Ciosi, Marc; Lombaert, Eric; Blin, Aurélie; Boriani, Marco; Furlan, Lorenzo; Toepfer, Stefan; Guillemaud, Thomas

    2012-01-01

    The western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), is one of the most destructive pests of corn in North America and is currently invading Europe. The two major invasive outbreaks of rootworm in Europe have occurred, in North-West Italy and in Central and South-Eastern Europe. These two outbreaks originated from independent introductions from North America. Secondary contact probably occurred in North Italy between these two outbreaks, in 2008. We used 13 microsatellite markers to conduct a population genetics study, to demonstrate that this geographic contact resulted in a zone of admixture in the Italian region of Veneto. We show that i) genetic variation is greater in the contact zone than in the parental outbreaks; ii) several signs of admixture were detected in some Venetian samples, in a bayesian analysis of the population structure and in an approximate bayesian computation analysis of historical scenarios and, finally, iii) allelic frequency clines were observed at microsatellite loci. The contact between the invasive outbreaks in North-West Italy and Central and South-Eastern Europe resulted in a zone of admixture, with particular characteristics. The evolutionary implications of the existence of a zone of admixture in Northern Italy and their possible impact on the invasion success of the western corn rootworm are discussed.

  3. A STUDY OF THE EFFECTS OF POST-COMBUSTION AMMONIA INJECTION ON FLY ASH QUALITY: CHARACTERIZATION OF AMMONIA RELEASE FROM CONCRETE AND MORTARS CONTAINING FLY ASH AS A POZZOLANIC ADMIXTURE

    SciTech Connect

    Robert F. Rathbone; Thomas L. Robl

    2001-10-11

    Work completed in this reporting period focused on the measurement of the rate of ammonia loss from mortar and concrete, and the measurement of ammonia gas in the air above the materials immediately after placement. The majority of mortar experiments have been completed, and testing has begun on concrete. The mortar experiments indicate that the rate of ammonia loss is greater in mortars prepared using a higher water content and water:cement (W:C) ratio, although the higher rate is primarily observed within the first 2 days, after which the loss rates are nearly the same. The source of low-calcium (Class F) fly ash exerted a negligible influence on the loss rate. However, mortar prepared using a higher-calcium fly ash evolved ammonia at a slightly slower rate than the Class F ash mortars. The data also indicate that an increase in ventilation increases the ammonia loss rate from mortar, and suggest that a well-ventilated space could substantially increase the loss of ammonia from mortar and, by inference, a concrete slab. Analysis of ammonia concentrations in the air above freshly-placed mortars in an enclosed space indicate that the fly ash ammonia concentration should not exceed 100 mg N/kg ash in confined space applications. For most other applications with some ventilation the maximum acceptable concentration would be approximately 200 mg/kg. Early results from experiments on concrete suggest that, under similar conditions, ammonia diffusion from concrete occurs at a higher rate than in mortar. In addition, increasing the slump of concrete through the use of chemical admixtures has only a minor effect on the ammonia loss rate.

  4. A STUDY OF THE EFFECTS OF POST-COMBUSTION AMMONIA INJECTION ON FLY ASH QUALITY: CHARACTERIZATION OF AMMONIA RELEASE FROM CONCRETE AND MORTARS CONTAINING FLY ASH AS A POZZOLANIC ADMIXTURE

    SciTech Connect

    Robert F. Rathbone; Thomas L. Robl

    2001-04-11

    Work completed in this reporting period focused on finalization of the Work and Management Plan, sample acquisition and analysis, evaluation of ammonia measurement methods, and measurement of ammonia loss from mortar. All fly ash samples have been acquired and analyzed for chemical composition and particle fineness. Three non-ammoniated fly ash samples were obtained from power plants that do not inject ammonia for NOx or particulate control, while three ammoniated fly ashes originate from plants that inject ammonia into the flue gas. The fly ash sources were selected based on their marketability as concrete admixtures and ammonia content. Coarse and fine aggregates for mortar and concrete testing have also been secured and have been thoroughly characterized using ASTM methods. Methodologies for the measurement of ammonia in the gaseous and aqueous phase have been carefully considered in the context of their suitability for use in this project. These include ammonia detection tubes, carbon impregnated with sulfuric acid (CISA) tubes, titration, and electrochemical methods. It was concluded that each of these methods is potentially useful for different aspects of the project, depending on the phase and concentration of ammonia to be measured. Preparation of fly ash-containing mortars both with and without ammonia indicated that the ammonia has no significant influence on compressive strength. Finally, measurement of ammonia loss from mortar has begun and the results of several of these experiments are included herein. It has been found that, under the laboratory curing conditions devised, ammonia release from mortar occurs at a relatively rapid rate in the first 24 hours, proceeded by a much slower, essentially linear rate. Furthermore, at the end of the three-week experiments, it was calculated that greater than 80% of the initial ammonia concentration remained within the mortar.

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

    PubMed Central

    Smith, Brad L.; Lu, Ching-Ping; García-Cortés, Blanca; Viñas, Jordi; Yeh, Shean-Ya; Alvarado Bremer, Jaime R.

    2015-01-01

    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. PMID:26057382

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

    PubMed

    Smith, Brad L; Lu, Ching-Ping; García-Cortés, Blanca; Viñas, Jordi; Yeh, Shean-Ya; Alvarado Bremer, Jaime R

    2015-01-01

    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.

  7. Gamification in Education: A Systematic Mapping Study

    ERIC Educational Resources Information Center

    Dicheva, Darina; Dichev, Christo; Agre, Gennady; Angelova, Galia

    2015-01-01

    While gamification is gaining ground in business, marketing, corporate management, and wellness initiatives, its application in education is still an emerging trend. This article presents a study of the published empirical research on the application of gamification to education. The study is limited to papers that discuss explicitly the effects…

  8. Urban geochemical mapping studies: how and why we do them.

    PubMed

    Johnson, Christopher C; Ander, E Louise

    2008-12-01

    Geochemical mapping is a technique rooted in mineral exploration but has now found worldwide application in studies of the urban environment. Such studies, involving multidisciplinary teams including geochemists, have to present their results in a way that nongeochemists can comprehend. A legislatively driven demand for urban geochemical data in connection with the need to identify contaminated land and subsequent health risk assessments has given rise to a greater worldwide interest in the urban geochemical environment. Herein, the aims and objectives of some urban studies are reviewed and commonly used terms such as baseline and background are defined. Geochemists need to better consider what is meant by the term urban. Whilst the unique make up of every city precludes a single recommended approach to a geochemical mapping strategy, more should be done to standardise the sampling and analytical methods. How (from a strategic and presentational point of view) and why we do geochemical mapping studies is discussed.

  9. Extensive Admixture and Selective Pressure Across the Sahel Belt

    PubMed Central

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

    2015-01-01

    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). PMID:26614524

  10. Expedient Low-Temperature Concrete Admixtures for the Army

    DTIC Science & Technology

    1999-11-01

    admixture is to depress the freezing point of by weight of cement in reinforced concrete and is water. This function depends on a colligative not...recommended at all in pre-stressed concrete. property called molality-the number of parti- But, for expedient purposes where long-term cles (moles) that...the freezing point because, as noted, the benchmark, they nearly equaled the strengths the colligative behavior of chemicals can vary of control

  11. A Study on the Use of Computerized Concept Mapping to Assist ESL Learners' Writing

    ERIC Educational Resources Information Center

    Liu, Pei-Lin

    2011-01-01

    This study aims to examine the effect of using computerized concept maps during the pre-writing phase on learners' writing performance. The research questions were: (1) What are the impacts of different computerized concept mapping treatments (no-mapping, individual-mapping, and cooperative-mapping) on writing performance for learners of different…

  12. A study of mapping exogenous knowledge representations into CONFIG

    NASA Technical Reports Server (NTRS)

    Mayfield, Blayne E.

    1992-01-01

    Qualitative reasoning is reasoning with a small set of qualitative values that is an abstraction of a larger and perhaps infinite set of quantitative values. The use of qualitative and quantitative reasoning together holds great promise for performance improvement in applications that suffer from large and/or imprecise knowledge domains. Included among these applications are the modeling, simulation, analysis, and fault diagnosis of physical systems. Several research groups continue to discover and experiment with new qualitative representations and reasoning techniques. However, due to the diversity of these techniques, it is difficult for the programs produced to exchange system models easily. The availability of mappings to transform knowledge from the form used by one of these programs to that used by another would open the doors for comparative analysis of these programs in areas such as completeness, correctness, and performance. A group at the Johnson Space Center (JSC) is working to develop CONFIG, a prototype qualitative modeling, simulation, and analysis tool for fault diagnosis applications in the U.S. space program. The availability of knowledge mappings from the programs produced by other research groups to CONFIG may provide savings in CONFIG's development costs and time, and may improve CONFIG's performance. The study of such mappings is the purpose of the research described in this paper. Two other research groups that have worked with the JSC group in the past are the Northwest University Group and the University of Texas at Austin Group. The former has produced a qualitative reasoning tool named SIMGEN, and the latter has produced one named QSIM. Another program produced by the Austin group is CC, a preprocessor that permits users to develop input for eventual use by QSIM, but in a more natural format. CONFIG and CC are both based on a component-connection ontology, so a mapping from CC's knowledge representation to CONFIG's knowledge

  13. Use of Technology-Assisted Techniques of Mind Mapping and Concept Mapping in Science Education: A Constructivist Study

    ERIC Educational Resources Information Center

    Balim, Ali Günay

    2013-01-01

    The study aims to investigate the effects of using mind maps and concept maps on students' learning of concepts in science courses. A total of 51 students participated in this study which used a quasi-experimental research design with pre-test/post-test control groups. The constructivist-inspired study was carried out in the sixth-grade science…

  14. The Sloan Digital Sky Survey Reverberation Mapping Project: Quasar Reverberation Mapping Studies

    NASA Astrophysics Data System (ADS)

    Grier, Catherine; SDSS-RM Collaboration

    2017-01-01

    The Sloan Digital Sky Survey Reverberation Mapping Project (SDSS-RM) has completed its first three years of spectroscopic observations of a sample of ~850 quasars with the SDSS-III BOSS spectrograph. From January-July in 2014, 2015, and 2016, more than 55 epochs of spectroscopy were obtained for this quasar sample, and continued monitoring has been approved for 2017. Supporting photometric observations were also carried out at the Canada-France-Hawaii Telescope and the Steward Observatory Bok telescope. In addition, the SDSS-RM field overlaps with the Pan-STARRS 1 Medium Deep Field MD07, so we have photometric data for three years prior to the SDSS-RM observations, which considerably extends the time delay sensitivity of the campaign. Preliminary reverberation mapping results were presented by Shen et al. (2015) and the program has also yielded ancillary science results in regimes such as broad absorption line variability, quasar ensemble variability characteristics, quasar emission line studies, SDSS quasar redshift measurements, and host galaxy properties. I will discuss the current status of the SDSS-RM program, including recent reverberation mapping results from the wider 850-quasar sample using the full set of first-year photometric and spectroscopic data.

  15. Genome-wide detection of natural selection in African Americans pre- and post-admixture.

    PubMed

    Jin, Wenfei; Xu, Shuhua; Wang, Haifeng; Yu, Yongguo; Shen, Yiping; Wu, Bailin; Jin, Li

    2012-03-01

    It is particularly meaningful to investigate natural selection in African Americans (AfA) due to the high mortality their African ancestry has experienced in history. In this study, we examined 491,526 autosomal single nucleotide polymorphisms (SNPs) genotyped in 5210 individuals and conducted a genome-wide search for selection signals in 1890 AfA. Several genomic regions showing an excess of African or European ancestry, which were considered the footprints of selection since population admixture, were detected based on a commonly used approach. However, we also developed a new strategy to detect natural selection both pre- and post-admixture by reconstructing an ancestral African population (AAF) from inferred African components of ancestry in AfA and comparing it with indigenous African populations (IAF). Interestingly, many selection-candidate genes identified by the new approach were associated with AfA-specific high-risk diseases such as prostate cancer and hypertension, suggesting an important role these disease-related genes might have played in adapting to a new environment. CD36 and HBB, whose mutations confer a degree of protection against malaria, were also located in the highly differentiated regions between AAF and IAF. Further analysis showed that the frequencies of alleles protecting against malaria in AAF were lower than those in IAF, which is consistent with the relaxed selection pressure of malaria in the New World. There is no overlap between the top candidate genes detected by the two approaches, indicating the different environmental pressures AfA experienced pre- and post-population admixture. We suggest that the new approach is reasonably powerful and can also be applied to other admixed populations such as Latinos and Uyghurs.

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

    NASA Astrophysics Data System (ADS)

    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.

  17. GIS-study and new Geomorphologic Mapping of Phobos

    NASA Astrophysics Data System (ADS)

    Kokhanov, Alexander; Lorenz, Cyrill; Karachevtseva, Irina

    2016-04-01

    Using raw images and processed orthoimages, obtained from "Mars Express", we have created a new GIS-catalog of grooves. During analysis, new grooves, not identified in earlier mapping attempts, were detected. For craters study the previously created catalog of craters with D >200 m [1] was used. The spatial orientation of individual grooves was estimated, which allows us to group them into several sets. All grooves in the catalog were divided into three morphological types: gutters (simple line depressions), chains of contiguous funnels, chains of noncontigual funnels. Studying craters we paid attention to its inner and outer morphology. The shape of some craters is different from the isometric. Among them were identified elliptical and polygonal craters. The study of inner morphology showed, that there prevails simple bowl-shaped craters. Also we identified a small population of craters with complex internal morphology [2], which, by analogy with similar lunar craters [3], divided into flat-bottomed, with a central mound and concentric craters. Moreover, based on elevation data, obtained from global digital elevation model [4] and calculation of relative depth, craters with D >2 km by the stage of degradation were classified. Focusing on a combination of grooves and craters, we have identified 15 morphological regions. A morphological unit was defined as a region with a certain type of relief, which differs from surrounding areas by the presence, orientation and spatial relations of groove systems and large craters (over 200 m). Each region may have its own geological history and consequently, specific history of regolith exposure. Finally, two geomorphologic maps of Phobos were created. One map represents the spatial distributions of grooves including their classifications by morphological types. The identified morphological regions are shown, and relief characteristics of these regions are briefly described. Geomorphologic map of craters shows the spatial

  18. Isolation with differentiation followed by expansion with admixture in the tunicate Pyura chilensis

    PubMed Central

    2013-01-01

    Background Pyura chilensis, a tunicate commercially exploited as food resource in Chile, is subject to management strategies, including restocking. The goal of this study was to examine the genetic structure of P. chilensis using information from a mitochondrial gene (Cytochrome Oxidase I, COI) and a nuclear gene (Elongation 1 alpha, EF1a), to characterize the geographic distribution of genetic diversity and differentiation, and to identify the main processes that have shaped it. We analyzed 268 and 208 sequences of COI and EF1a, respectively, from samples of eight local populations covering ca. 1800 km. Results For Pyura chilensis, partial sequences of the gene COI revealed three highly supported haplogroups that diverged 260000 to 470000 years ago. Two haplogroups currently are widely distributed and sympatric, while one is dominant only in Los Molinos (LM, 39°50′S). The two widespread COI haplogroups underwent a geographic expansion during an interglacial period of the Late Pleistocene ca. 100000 years ago. The nuclear gene was less divergent and did not resolve the COI haplogroups. Bayesian clustering of the nuclear gene’s SNPs revealed that individuals from the two widespread COI haplogroups were mostly assigned to two of the three detected clusters and had a marked degree of admixture. The third cluster predominated in LM and showed low admixture. Haplotypic diversity of both genes was very high, there was no isolation by distance, and most localities were genetically undifferentiated; only LM was consistently differentiated with both genes analyzed. Conclusions Pyura chilensis has less genetic structure than expected given its life history, which could be a consequence of dispersal on ship hulls. The only differentiated local population analyzed was LM. Coincidentally, it is the one furthest away from main maritime routes along the coast of Chile. The use of mitochondrial and nuclear markers allowed detection of divergent mitochondrial haplogroups in

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

    PubMed Central

    Morello, Santiago; Sede, Silvana M.

    2016-01-01

    Mountain uplifts have generated new ecologic opportunities for plants, and triggered evolutionary processes, favouring an increase on the speciation rate in all continents. Moreover, mountain ranges may act as corridors or barriers for plant lineages and populations. In South America a high rate of diversification has been linked to Andean orogeny during Pliocene/Miocene. More recently, Pleistocene glacial cycles have also shaped species distribution and demography. The endemic genus Escallonia is known to have diversified in the Andes. Species with similar morphology obscure species delimitation and plants with intermediate characters occur naturally. The aim of this study is to characterize genetic variation and structure of two widespread species of Escallonia: E. alpina and E. rubra. We analyzed the genetic variation of populations of the entire distribution range of the species and we also included those with intermediate morphological characters; a total of 94 accessions from 14 populations were used for the Amplified Fragment Length Polymorphism (AFLP) analysis. Plastid DNA sequences (trnS-trnG, 3′trnV-ndhC intergenic spacers and the ndhF gene) from sixteen accessions of Escallonia species were used to construct a Statistical Parsimony network. Additionally, we performed a geometric morphometrics analysis on 88 leaves from 35 individuals of the two E. alpina varieties to further study their differences. Wright’s Fst and analysis of molecular variance tests performed on AFLP data showed a significant level of genetic structure at the species and population levels. Intermediate morphology populations showed a mixed genetic contribution from E. alpina var. alpina and E. rubra both in the Principal Coordinates Analysis (PCoA) and STRUCTURE. On the other hand, E. rubra and the two varieties of E. alpina are well differentiated and assigned to different genetic clusters. Moreover, the Statistical Parsimony network showed a high degree of divergence between the

  20. How important is intraspecific genetic admixture to the success of colonising populations?

    PubMed

    Rius, Marc; Darling, John A

    2014-04-01

    Genetic admixture of divergent intraspecific lineages is increasingly suspected to have an important role in the success of colonising populations. However, admixture is not a universally beneficial genetic phenomenon. Selection is typically expected to favour locally adapted genotypes and can act against admixed individuals, suggesting that there are some conditions under which admixture will have negative impacts on population fitness. Therefore, it remains unclear how often admixture acts as a true driver of colonisation success. Here, we review the population consequences of admixture and discuss its costs and benefits across a broad spectrum of ecological contexts. We critically evaluate the evidence for a causal role of admixture in successful colonisation, and consider that role more generally in driving population range expansion.

  1. a Study of Sasin-Animal Sky Map on Chonmunryucho

    NASA Astrophysics Data System (ADS)

    Yang, Hong-Jin; Park, Myeong-Gu

    2003-03-01

    Chon-Mun-Ryu-Cho, written (edited) by Lee Sun-Ji during the period of King Se-Jong, is a representative astronomy book of Cho-Sun (A.D. 1392 -1910) Dynasty. We find and study in the first page of the book; the description of 28 oriental constellations as a Sasin (four mythical oriental animals)-animal sky map which is not widely known yet. The map consists of four groups of constellations, each of which represents the Sasin: Chang-Ryong (dragon), Baek-Ho (tigers with Ki-Rin [Oriental giraffe]), Ju-Jak (Chinese phoenix), Hyun-Mu (a tortoise interwined with a snake). Each group (animals) spans 2˜7 of 28 oriental constellations As we know from the illustration of the Chon-Sang-Yol-Cha-Bun-Ya-Ji-Do a representative sky map of Cho-Sun Dynasty, astronomy in Cho-Sun Dynasty is closely related to that in Go-Gu-Ryer (B.C. 37 -A.D. 668) Dynasty. Since these Sasin-animals appear in most mural paintings of Go-Gu-Ryer tombs, visualization of sky with these animal constellations could have been established as early as in Go-Gu-Ryer Dynasty. We also reconstruct this ''A Sasin-animal Korean sky map'' based on the shapes of the Sasin and Ki-Rin from Go-Gu-Ryer paintings and 28 oriental constellations in Chon-Sang-Yol-Cha-Bun-Ya-Ji-Do.

  2. Effects of English admixture and geographic distance on anthropometric variation and genetic structure in 19th-century Ireland.

    PubMed

    Relethford, J H

    1988-05-01

    The analysis of anthropometric data often allows investigation of patterns of genetic structure in historical populations. This paper focuses on interpopulational anthropometric variation in seven populations in Ireland using data collected in the 1890s. The seven populations were located within a 120-km range along the west coast of Ireland and include islands and mainland isolates. Two of the populations (the Aran Islands and Inishbofin) have a known history of English admixture in earlier centuries. Ten anthropometric measures (head length, breadth, and height; nose length and breadth; bizygomatic and bigonial breadth; stature; hand length; and forearm length) on 259 adult Irish males were analyzed following age adjustment. Discriminant and canonical variates analysis were used to determine the degree and pattern of among-group variation. Mahalanobis' distance measure, D2, was computed between each pair of populations and compared to distance measures based on geographic distance and English admixture (a binary measure indicating whether either of a pair of populations had historical indications of admixture). In addition, surname frequencies were used to construct distance measures based on random isonymy. Correlations were computed between distance measures, and their probabilities were derived using the Mantel matrix permutation method. English admixture has the greatest effect on anthropometric variation among these populations, followed by geographic distance. The correlation between anthropometric distance and geographic distance is not significant (r = -0.081, P = .590), but the correlation of admixture and anthropometric distance is significant (r = 0.829, P = .047). When the two admixed populations are removed from the analysis the correlation between geographic and anthropometric distance becomes significant (r = 0.718, P = .025). Isonymy distance shows a significant correlation with geographic distance (r = 0.425, P = .046) but not with admixture

  3. Chemical and structural properties of Jordanian zeolitic tuffs and their admixtures with urea and thiourea: Potential scavengers for phenolics in aqueous medium

    SciTech Connect

    Yousef, R.I.; Tutunji, M.F.; Derwish, G.A.W.; Musleh, S.M.

    1999-08-15

    Native Jordanian zeolitic tuffs, rich in phillipsite, were treated with urea and thiourea. The chemical and structural properties of the tuffs and their urea and thiourea admixtures were studied using SEM, XRF, XRD, and FTIR techniques, and their adsorption capacities were estimated by the methylene blue method. The urea and thiourea treatment has not affected the mineral constitution of the tuffs. The results revealed that urea and thiourea were linked by hydrogen bonding through the NH{sub 2} moiety to the zeolite substrate, with urea showing the strongest effect. Experiments were carried out to investigate the possible use of the prepared materials for the removal of phenol and chlorinated phenols from aqueous solutions. Although thiourea caused a reduction in the relative surface area, both urea and thiourea admixtures were more effective than the free zeolitic tuff in the removal of phenol and chlorinated phenols from water, with urea admixture displaying the largest removal capacity.

  4. Differential Evolution approach to detect recent admixture.

    PubMed

    Kozlov, Konstantin; Chebotarev, Dmitri; Hassan, Mehedi; Triska, Martin; Triska, Petr; Flegontov, Pavel; Tatarinova, Tatiana V

    2015-01-01

    The genetic structure of human populations is extraordinarily complex and of fundamental importance to studies of anthropology, evolution, and medicine. As increasingly many individuals are of mixed origin, there is an unmet need for tools that can infer multiple origins. Misclassification of such individuals can lead to incorrect and costly misinterpretations of genomic data, primarily in disease studies and drug trials. We present an advanced tool to infer ancestry that can identify the biogeographic origins of highly mixed individuals. reAdmix can incorporate individual's knowledge of ancestors (e.g. having some ancestors from Turkey or a Scottish grandmother). reAdmix is an online tool available at http://chcb.saban-chla.usc.edu/reAdmix/.

  5. Differential Evolution approach to detect recent admixture

    PubMed Central

    2015-01-01

    The genetic structure of human populations is extraordinarily complex and of fundamental importance to studies of anthropology, evolution, and medicine. As increasingly many individuals are of mixed origin, there is an unmet need for tools that can infer multiple origins. Misclassification of such individuals can lead to incorrect and costly misinterpretations of genomic data, primarily in disease studies and drug trials. We present an advanced tool to infer ancestry that can identify the biogeographic origins of highly mixed individuals. reAdmix can incorporate individual's knowledge of ancestors (e.g. having some ancestors from Turkey or a Scottish grandmother). reAdmix is an online tool available at http://chcb.saban-chla.usc.edu/reAdmix/. PMID:26111206

  6. History Shaped the Geographic Distribution of Genomic Admixture on the Island of Puerto Rico

    PubMed Central

    Via, Marc; Gignoux, Christopher R.; Roth, Lindsey A.; Fejerman, Laura; Galanter, Joshua; Choudhry, Shweta; Toro-Labrador, Gladys; Viera-Vera, Jorge; Oleksyk, Taras K.; Beckman, Kenneth; Ziv, Elad; Risch, Neil

    2011-01-01

    Contemporary genetic variation among Latin Americans human groups reflects population migrations shaped by complex historical, social and economic factors. Consequently, admixture patterns may vary by geographic regions ranging from countries to neighborhoods. We examined the geographic variation of admixture across the island of Puerto Rico and the degree to which it could be explained by historic and social events. We analyzed a census-based sample of 642 Puerto Rican individuals that were genotyped for 93 ancestry informative markers (AIMs) to estimate African, European and Native American ancestry. Socioeconomic status (SES) data and geographic location were obtained for each individual. There was significant geographic variation of ancestry across the island. In particular, African ancestry demonstrated a decreasing East to West gradient that was partially explained by historical factors linked to the colonial sugar plantation system. SES also demonstrated a parallel decreasing cline from East to West. However, at a local level, SES and African ancestry were negatively correlated. European ancestry was strongly negatively correlated with African ancestry and therefore showed patterns complementary to African ancestry. By contrast, Native American ancestry showed little variation across the island and across individuals and appears to have played little social role historically. The observed geographic distributions of SES and genetic variation relate to historical social events and mating patterns, and have substantial implications for the design of studies in the recently admixed Puerto Rican population. More generally, our results demonstrate the importance of incorporating social and geographic data with genetics when studying contemporary admixed populations. PMID:21304981

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

    PubMed Central

    Mühlebach, S.; Franken, C.; Stanga, Z.

    2009-01-01

    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). PMID:20049073

  8. Analysis of Ethnic Admixture in Prostate Cancer

    DTIC Science & Technology

    2006-12-01

    The Study of Early Onset Prostate Cancer (1993–1995) was based in the San Francisco –Oakland Bay Area and included only individuals with histologically...Matusik R, Thomas GV, Sawyers CL (2003) Cancer Cell 4:223–238. 23. Williams K, Fernandez S, Stien X, Ishii K, Love HD, Lau YF, Roberts RL, Hayward SW (2005...Genet 2003;12(22):3007–3016. 11. Sarrio D, Moreno -Bueno G, Hardisson D, Sanchez-Estevez C, Guo M, Herman J, Gamallo C, Esteller M, Palacios J. Epigenetic

  9. Effect of Admixtures of Surface-Active Elements in Fe - C - Si Alloys Under Rapid Solidification of Melt on the Quality of Structural Articles

    NASA Astrophysics Data System (ADS)

    Belyakova, R. M.; Polukhin, V. A.; Kurbanova, E. D.

    2016-07-01

    Computer and experimental studies of the effect of admixtures of Te and H2 surface-active elements (s.a.e.) on the kinetics of nucleation of crystallization centers and phase growth under accelerated crystallization of eutectic cast iron are performed. It is shown that under quenching cooling with decelerated diffusion processes the admixtures of s.a.e. in the melt play the role of initiators of diffusion redistribution of elements in formation and growth of new phase fragments affecting the structure and properties of the formed material.

  10. Admixture in Latin America: geographic structure, phenotypic diversity and self-perception of ancestry based on 7,342 individuals.

    PubMed

    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

    2014-09-01

    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.

  11. Complex Patterns of Genomic Admixture within Southern Africa

    PubMed Central

    Petersen, Desiree C.; Libiger, Ondrej; Tindall, Elizabeth A.; Hardie, Rae-Anne; Hannick, Linda I.; Glashoff, Richard H.; Mukerji, Mitali; Fernandez, Pedro; Haacke, Wilfrid; Schork, Nicholas J.; Hayes, Vanessa M.

    2013-01-01

    Within-population genetic diversity is greatest within Africa, while between-population genetic diversity is directly proportional to geographic distance. The most divergent contemporary human populations include the click-speaking forager peoples of southern Africa, broadly defined as Khoesan. Both intra- (Bantu expansion) and inter-continental migration (European-driven colonization) have resulted in complex patterns of admixture between ancient geographically isolated Khoesan and more recently diverged populations. Using gender-specific analysis and almost 1 million autosomal markers, we determine the significance of estimated ancestral contributions that have shaped five contemporary southern African populations in a cohort of 103 individuals. Limited by lack of available data for homogenous Khoesan representation, we identify the Ju/'hoan (n = 19) as a distinct early diverging human lineage with little to no significant non-Khoesan contribution. In contrast to the Ju/'hoan, we identify ancient signatures of Khoesan and Bantu unions resulting in significant Khoesan- and Bantu-derived contributions to the Southern Bantu amaXhosa (n = 15) and Khoesan !Xun (n = 14), respectively. Our data further suggests that contemporary !Xun represent distinct Khoesan prehistories. Khoesan assimilation with European settlement at the most southern tip of Africa resulted in significant ancestral Khoesan contributions to the Coloured (n = 25) and Baster (n = 30) populations. The latter populations were further impacted by 170 years of East Indian slave trade and intra-continental migrations resulting in a complex pattern of genetic variation (admixture). The populations of southern Africa provide a unique opportunity to investigate the genomic variability from some of the oldest human lineages to the implications of complex admixture patterns including ancient and recently diverged human lineages. PMID:23516368

  12. Population genetics of Mediterranean and Saharan olives: geographic patterns of differentiation and evidence for early generations of admixture

    PubMed Central

    Besnard, G.; El Bakkali, A.; Haouane, H.; Baali-Cherif, D.; Moukhli, A.; Khadari, B.

    2013-01-01

    Background and Aims The olive (Olea europaea subsp. europaea) was domesticated in the Mediterranean area but its wild relatives are distributed over three continents, from the Mediterranean basin to South Africa and south-western Asia. Recent studies suggested that this crop originated in the Levant while a secondary diversification occurred in most westward areas. A possible contribution of the Saharan subspecies (subsp. laperrinei) has been highlighted, but the data available were too limited to draw definite conclusions. Here, patterns of genetic differentiation in the Mediterranean and Saharan olives are analysed to test for recent admixture between these taxa. Methods Nuclear microsatellite and plastid DNA (ptDNA) data were compiled from previous studies and completed for a sample of 470 cultivars, 390 wild Mediterranean trees and 270 Saharan olives. A network was reconstructed for the ptDNA haplotypes, while a Bayesian clustering method was applied to identify the main gene pools in the data set and then simulate and test for early generations of admixture between Mediterranean and Saharan olives. Key Results Four lineages of ptDNA haplotypes are recognized: three from the Mediterranean basin and one from the Sahara. Only one haplotype, primarily distributed in the Sahara, is shared between laperrinei and europaea. This haplotype is detected once in ‘Dhokar’, a cultivar from the Maghreb. Nuclear microsatellites show geographic patterns of genetic differentiation in the Mediterranean olive that reflect the primary origins of cultivars in the Levant, and indicate a high genetic differentiation between europaea and laperrinei. No first-generation hybrid between europaea and laperrinei is detected, but recent, reciprocal admixture between Mediterranean and Saharan subspecies is found in a few accessions, including ‘Dhokar’. Conclusions This study reports for the first time admixture between Mediterranean and Saharan olives. Although its contribution

  13. Genome-wide analysis of admixture and adaptation in the Africanized honeybee.

    PubMed

    Nelson, Ronald M; Wallberg, Andreas; Simões, Zilá Luz Paulino; Lawson, Daniel J; Webster, Matthew T

    2017-04-05

    Genetic exchange by hybridization or admixture can make an important contribution to evolution, and introgression of favourable alleles can facilitate adaptation to new environments. A small number of honeybees (Apis mellifera) with African ancestry were introduced to Brazil ~60 years ago, which dispersed and hybridized with existing managed populations of European origin, quickly spreading across much of the Americas in an example of a massive biological invasion. Here we analyse whole genome sequences of 32 Africanized honeybees sampled from throughout Brazil in order to study the effect of this process on genome diversity. By comparison with ancestral populations from Europe and Africa, we infer that these samples have 84% African ancestry, with the remainder from western European populations. However, this proportion varies across the genome and we identify signals of positive selection in regions with high European ancestry proportions. These observations are largely driven by one large gene-rich 1.4-Mbp segment on chromosome 11 where European haplotypes are present at a significantly elevated frequency and likely confer an adaptive advantage in the Africanized honeybee population. This region has previously been implicated in reproductive traits and foraging behaviour in worker bees. Finally, by analysing the distribution of ancestry tract lengths in the context of the known time of the admixture event, we are able to infer an average generation time of 2.0 years. Our analysis highlights the processes by which populations of mixed genetic ancestry form and adapt to new environments. This article is protected by copyright. All rights reserved.

  14. Activation analysis of admixtures in certain semiconductive materials

    NASA Technical Reports Server (NTRS)

    Artyukhin, P. I.; Gilbert, E. P.; Pronin, V. A.

    1978-01-01

    The use of extractions and chromatographic operations to separate macrobases, and to divide elements into groups convenient for gamma-spectrometric analysis is discussed. Methods are described for the activation detection of some impurities in silicon, arsenic, thallium, and trichloromethylsilane, on the basis of the extraction properties of bis(2-chlorethyl ether) and dimethylbenzylalkylammonium chloride. A schematic diagram of the extraction separation of elements-admixture is presented showing the aqueous and organic phases. The content percentage of the various elements are given in tables.

  15. A minimum set of ancestry informative markers for determining admixture proportions in a mixed American population: the Brazilian set.

    PubMed

    Santos, Hadassa C; Horimoto, Andréa V R; Tarazona-Santos, Eduardo; Rodrigues-Soares, Fernanda; Barreto, Mauricio L; Horta, Bernardo L; Lima-Costa, Maria F; Gouveia, Mateus H; Machado, Moara; Silva, Thiago M; Sanches, José M; Esteban, Nubia; Magalhaes, Wagner C S; Rodrigues, Maíra R; Kehdy, Fernanda S G; Pereira, Alexandre C

    2016-05-01

    The Brazilian population is considered to be highly admixed. The main contributing ancestral populations were European and African, with Amerindians contributing to a lesser extent. The aims of this study were to provide a resource for determining and quantifying individual continental ancestry using the smallest number of SNPs possible, thus allowing for a cost- and time-efficient strategy for genomic ancestry determination. We identified and validated a minimum set of 192 ancestry informative markers (AIMs) for the genetic ancestry determination of Brazilian populations. These markers were selected on the basis of their distribution throughout the human genome, and their capacity of being genotyped on widely available commercial platforms. We analyzed genotyping data from 6487 individuals belonging to three Brazilian cohorts. Estimates of individual admixture using this 192 AIM panels were highly correlated with estimates using ~370 000 genome-wide SNPs: 91%, 92%, and 74% of, respectively, African, European, and Native American ancestry components. Besides that, 192 AIMs are well distributed among populations from these ancestral continents, allowing greater freedom in future studies with this panel regarding the choice of reference populations. We also observed that genetic ancestry inferred by AIMs provides similar association results to the one obtained using ancestry inferred by genomic data (370 K SNPs) in a simple regression model with rs1426654, related to skin pigmentation, genotypes as dependent variable. In conclusion, these markers can be used to identify and accurately quantify ancestry of Latin Americans or US Hispanics/Latino individuals, in particular in the context of fine-mapping strategies that require the quantification of continental ancestry in thousands of individuals.

  16. Study of smartphone suitability for mapping of skin chromophores

    NASA Astrophysics Data System (ADS)

    Kuzmina, Ilona; Lacis, Matiss; Spigulis, Janis; Berzina, Anna; Valeine, Lauma

    2015-09-01

    RGB (red-green-blue) technique for mapping skin chromophores by smartphones is proposed and studied. Three smartphones of different manufacturers were tested on skin phantoms and in vivo on benign skin lesions using a specially designed light source for illumination. Hemoglobin and melanin indices obtained by these smartphones showed differences in both tests. In vitro tests showed an increment of hemoglobin and melanin indices with the concentration of chromophores in phantoms. In vivo tests indicated higher hemoglobin index in hemangiomas than in nevi and healthy skin, and nevi showed higher melanin index compared to the healthy skin. Smartphones that allow switching off the automatic camera settings provided useful data, while those with "embedded" automatic settings appear to be useless for distant skin chromophore mapping.

  17. Mapping the informal science education landscape: An exploratory study.

    PubMed

    Falk, John H; Randol, Scott; Dierking, Lynn D

    2012-10-01

    This study investigated the informal science education (ISE) field to determine whether it currently functions as an effective community of practice. Research questions included: How do professionals describe and self-identify their practice, including what missions, goals and motivating factors influence their professional work? What challenges do they face and how are these resolved? Is participation in ISE activities perceived as core or peripheral to their work? Open-ended interviews were conducted with high-level representatives of 17 different ISE sub-communities; results were analyzed qualitatively. Findings showed this broad assortment of ISE sub-communities as not currently functioning as a cohesive community of practice. Although examples of shared practice and ways of talking were found, evidence of widespread, active relationship-building over time and coalescence around issues of common concern were absent. A current "map" of the ISE community is proposed and thoughts about how this map could alter in the future are suggested.

  18. Nuclear species-diagnostic SNP markers mined from 454 amplicon sequencing reveal admixture genomic structure of modern citrus varieties.

    PubMed

    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

  19. Nuclear Species-Diagnostic SNP Markers Mined from 454 Amplicon Sequencing Reveal Admixture Genomic Structure of Modern Citrus Varieties

    PubMed Central

    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

  20. Genetic structure and admixture between Bayash Roma from northwestern Croatia and general Croatian population: evidence from Bayesian clustering analysis.

    PubMed

    Novokmet, Natalija; Galov, Ana; Marjanović, Damir; Škaro, Vedrana; Projić, Petar; Lauc, Gordan; Primorac, Dragan; Rudan, Pavao

    2015-01-01

    The European Roma represent a transnational mosaic of minority population groups with different migration histories and contrasting experiences in their interactions with majority populations across the European continent. Although historical genetic contributions of European lineages to the Roma pool were investigated before, the extent of contemporary genetic admixture between Bayash Roma and non-Romani majority population remains elusive. The aim of this study was to assess the genetic structure of the Bayash Roma population from northwestern Croatia and the general Croatian population and to investigate the extent of admixture between them. A set of genetic data from two original studies (100 Bayash Roma from northwestern Croatia and 195 individuals from the general Croatian population) was analyzed by Bayesian clustering implemented in STRUCTURE software. By re-analyzing published data we intended to focus for the first time on genetic differentiation and structure and in doing so we clearly pointed to the importance of considering social phenomena in understanding genetic structuring. Our results demonstrated that two population clusters best explain the genetic structure, which is consistent with social exclusion of Roma and the demographic history of Bayash Roma who have settled in NW Croatia only about 150 years ago and mostly applied rules of endogamy. The presence of admixture was revealed, while the percentage of non-Croatian individuals in general Croatian population was approximately twofold higher than the percentage of non-Romani individuals in Roma population corroborating the presence of ethnomimicry in Roma.

  1. Human Leukocyte Antigen Profiles of Latin American Populations: Differential Admixture and Its Potential Impact on Hematopoietic Stem Cell Transplantation

    PubMed Central

    Arrieta-Bolaños, Esteban; Madrigal, J. Alejandro; Shaw, Bronwen E.

    2012-01-01

    The outcome of hematopoietic stem cell transplantation (HSCT) is shaped by both clinical and genetic factors that determine its success. Genetic factors including human leukocyte antigen (HLA) and non-HLA genetic variants are believed to influence the risk of potentially fatal complications after the transplant. Moreover, ethnicity has been proposed as a factor modifying the risk of graft-versus-host disease. The populations of Latin America are a complex array of different admixture processes with varying degrees of ancestral population proportions that came in different migration waves. This complexity makes the study of genetic risks in this region complicated unless the extent of this variation is thoroughly characterized. In this study we compared the HLA-A and HLA-B allele group profiles for 31 Latin American populations and 61 ancestral populations from Iberia, Italy, Sub-Saharan Africa, and America. Results from population genetics comparisons show a wide variation in the HLA profiles from the Latin American populations that correlate with different admixture proportions. Populations in Latin America seem to be organized in at least three groups with (1) strong Amerindian admixture, (2) strong Caucasian component, and (3) a Caucasian-African gradient. These results imply that genetic risk assessment for HSCT in Latin America has to be adapted for different population subgroups rather than as a pan-Hispanic/Latino analysis. PMID:23213535

  2. Open source projects in software engineering education: a mapping study

    NASA Astrophysics Data System (ADS)

    Nascimento, Debora M. C.; Almeida Bittencourt, Roberto; Chavez, Christina

    2015-01-01

    Context: It is common practice in academia to have students work with "toy" projects in software engineering (SE) courses. One way to make such courses more realistic and reduce the gap between academic courses and industry needs is getting students involved in open source projects (OSP) with faculty supervision. Objective: This study aims to summarize the literature on how OSP have been used to facilitate students' learning of SE. Method: A systematic mapping study was undertaken by identifying, filtering and classifying primary studies using a predefined strategy. Results: 72 papers were selected and classified. The main results were: (a) most studies focused on comprehensive SE courses, although some dealt with specific areas; (b) the most prevalent approach was the traditional project method; (c) studies' general goals were: learning SE concepts and principles by using OSP, learning open source software or both; (d) most studies tried out ideas in regular courses within the curriculum; (e) in general, students had to work with predefined projects; (f) there was a balance between approaches where instructors had either inside control or no control on the activities performed by students; (g) when learning was assessed, software artefacts, reports and presentations were the main instruments used by teachers, while surveys were widely used for students' self-assessment; (h) most studies were published in the last seven years. Conclusions: The resulting map gives an overview of the existing initiatives in this context and shows gaps where further research can be pursued.

  3. Cuba: Exploring the History of Admixture and the Genetic Basis of Pigmentation Using Autosomal and Uniparental Markers

    PubMed Central

    Fuentes-Smith, Evelyn; Salas, Antonio; Buttenschøn, Henriette N.; Demontis, Ditte; Torres-Español, María; Marín-Padrón, Lilia C.; Gómez-Cabezas, Enrique J.; Álvarez-Iglesias, Vanesa; Mosquera-Miguel, Ana; Martínez-Fuentes, Antonio; Carracedo, Ángel; Børglum, Anders D.; Mors, Ole

    2014-01-01

    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

  4. Review of radiation damage studies on DNW CMOS MAPS

    NASA Astrophysics Data System (ADS)

    Traversi, G.; Gaioni, L.; Manazza, A.; Manghisoni, M.; Ratti, L.; Re, V.; Zucca, S.; Bettarini, S.; Rizzo, G.; Morsani, F.; Bosisio, L.; Rashevskaya, I.; Cindro, V.

    2013-12-01

    Monolithic active pixel sensors fabricated in a bulk CMOS technology with no epitaxial layer and standard resistivity (10 Ω cm) substrate, featuring a deep N-well as the collecting electrode (DNW MAPS), have been exposed to γ-rays, up to a final dose of 10 Mrad (SiO2), and to neutrons from a nuclear reactor, up to a total 1 MeV neutron equivalent fluence of about 3.7 ·1013cm-2. The irradiation campaign was aimed at studying the effects of radiation on the most significant parameters of the front-end electronics and on the charge collection properties of the sensors. Device characterization has been carried out before and after irradiations. The DNW MAPS irradiated with 60Co γ-rays were also subjected to high temperature annealing (100 °C for 168 h). Measurements have been performed through a number of different techniques, including electrical characterization of the front-end electronics and of DNW diodes, laser stimulation of the sensors and tests with 55Fe and 90Sr radioactive sources. This paper reviews the measurement results, their relation with the damage mechanisms underlying performance degradation and provides a new comparison between DNW devices and MAPS fabricated in a CMOS process with high resistivity (1 kΩ cm) epitaxial layer.

  5. 3D Regression Heat Map Analysis of Population Study Data.

    PubMed

    Klemm, Paul; Lawonn, Kai; Glaßer, Sylvia; Niemann, Uli; Hegenscheid, Katrin; Völzke, Henry; Preim, Bernhard

    2016-01-01

    Epidemiological studies comprise heterogeneous data about a subject group to define disease-specific risk factors. These data contain information (features) about a subject's lifestyle, medical status as well as medical image data. Statistical regression analysis is used to evaluate these features and to identify feature combinations indicating a disease (the target feature). We propose an analysis approach of epidemiological data sets by incorporating all features in an exhaustive regression-based analysis. This approach combines all independent features w.r.t. a target feature. It provides a visualization that reveals insights into the data by highlighting relationships. The 3D Regression Heat Map, a novel 3D visual encoding, acts as an overview of the whole data set. It shows all combinations of two to three independent features with a specific target disease. Slicing through the 3D Regression Heat Map allows for the detailed analysis of the underlying relationships. Expert knowledge about disease-specific hypotheses can be included into the analysis by adjusting the regression model formulas. Furthermore, the influences of features can be assessed using a difference view comparing different calculation results. We applied our 3D Regression Heat Map method to a hepatic steatosis data set to reproduce results from a data mining-driven analysis. A qualitative analysis was conducted on a breast density data set. We were able to derive new hypotheses about relations between breast density and breast lesions with breast cancer. With the 3D Regression Heat Map, we present a visual overview of epidemiological data that allows for the first time an interactive regression-based analysis of large feature sets with respect to a disease.

  6. Safety of compounded calcium chloride admixtures for peripheral intravenous administration in the setting of a calcium gluconate shortage.

    PubMed

    Anger, Kevin E; Belisle, Caryn; Colwell, Megan B; Dannemiller, Robert; Alawadhi, Burhan; Wilkocki, Alex; Szumita, Paul M

    2014-10-01

    Calcium gluconate is preferred over calcium chloride for intravenous (IV) repletion of calcium deficiencies in the inpatient setting. In the setting of a national shortage of IV calcium gluconate, our institution implemented a compounded calcium chloride admixture for IV administration. The objective of this analysis is to evaluate the peripheral infusion site safety of compounded IV calcium chloride admixtures in adult inpatients. A total of 222 patients, encompassing 224 inpatient admissions, from April to June 2011 were retrospectively reviewed. Sterile preparations of calcium chloride in 5% dextrose (600 mg/250 mL and 300 mg/100 mL) were used during the study time period. Adverse infusion site reactions were assessed using an institutional infiltration and phlebitis grading system. A total of 333 doses were administered peripherally. In all, 4 (1.8%) patients experienced a moderate to severe infusion site reaction, with 3 due to phlebitis and 1 due to infiltration. Naranjo Nomogram for Adverse Drug Reaction Assessment classified all 4 reactions to have a possible link to calcium chloride administration. Peripheral administration of compounded calcium chloride admixtures in 5% dextrose is associated with a low incidence of IV infusion site reactions and can be considered as an alternative in the event of a calcium gluconate shortage.

  7. Apparent variation in Neanderthal admixture among African populations is consistent with gene flow from Non-African populations.

    PubMed

    Wang, Shuoguo; Lachance, Joseph; Tishkoff, Sarah A; Hey, Jody; Xing, Jinchuan

    2013-01-01

    Recent studies have found evidence of introgression from Neanderthals into modern humans outside of sub-Saharan Africa. Given the geographic range of Neanderthals, the findings have been interpreted as evidence of gene exchange between Neanderthals and modern humans descended from the Out-of-Africa (OOA) migration. Here, we examine an alternative interpretation in which the introgression occurred earlier within Africa, between ancestors or relatives of Neanderthals and a subset of African modern humans who were the ancestors of those involved in the OOA migration. Under the alternative model, if the population structure among present-day Africans predates the OOA migration, we might find some African populations show a signal of Neanderthal introgression whereas others do not. To test this alternative model, we compiled a whole-genome data set including 38 sub-Saharan Africans from eight populations and 25 non-African individuals from five populations. We assessed differences in the amount of Neanderthal-like single-nucleotide polymorphism alleles among these populations and observed up to 1.5% difference in the number of Neanderthal-like alleles among African populations. Further analyses suggest that these differences are likely due to recent non-African admixture in these populations. After accounting for recent non-African admixture, our results do not support the alternative model of older (e.g., >100 kya) admixture between modern humans and Neanderthal-like hominids within Africa.

  8. Assessment of anti-factor Xa activity of heparin in binary parenteral nutrition admixtures for premature neonates.

    PubMed

    Foinard, A; Perez, M; Barthélémy, C; Lannoy, D; Flamein, F; Storme, L; Tournoys, A; Décaudin, B; Odou, P

    2015-07-01

    An in vitro study was carried out to determine the anti-Xa activity of heparin in binary parenteral nutrition (BPN) admixtures for premature neonates in our neonatal intensive care unit (NICU) after a 24-hour infusion, as well as to assess drug interaction with a 50% glucose solution. Two types of bags were prepared: (1) BPN admixtures (composition defined in the NICU) including sodium heparin at 77 UI/mL and (2) bags containing only G50% with sodium heparin at 193 UI/mL. The anti-Xa activity of heparin was measured in bags at T0, after the 24-hour infusion and in eluates at the outlet of the infusion line after 24hours, using a validated chromogenic anti-Xa method. Comparisons of the mean concentration observed with the theoretical value for anti-Xa activity were performed with the Student t-test. Mean values of anti-Xa activity do not differ significantly from the values expected for all conditions. We found a slight variation in anti-Xa activity when infused over 24hours for both types of bags, with and without in-line filtration, showing that heparin remains stable during this infusion period in both BPN admixtures and G50%.

  9. Urban Groundwater Mapping - Bucharest City Area Case Study

    NASA Astrophysics Data System (ADS)

    Gaitanaru, Dragos; Radu Gogu, Constantin; Bica, Ioan; Anghel, Leonard; Amine Boukhemacha, Mohamed; Ionita, Angela

    2013-04-01

    Urban Groundwater Mapping (UGM) is a generic term for a collection of procedures and techniques used to create targeted cartographic representation of the groundwater related aspects in urban areas. The urban environment alters the physical and chemical characteristics of the underneath aquifers. The scale of the pressure is controlled by the urban development in time and space. To have a clear image on the spatial and temporal distribution of different groundwater- urban structures interaction we need a set of thematic maps is needed. In the present study it is described the methodological approach used to obtain a reliable cartographic product for Bucharest City area. The first step in the current study was to identify the groundwater related problems and aspects (changes in the groundwater table, infiltration and seepage from and to the city sewer network, contamination spread to all three aquifers systems located in quaternary sedimentary formations, dewatering impact for large underground structures, management and political drawbacks). The second step was data collection and validation. In urban areas there is a big spectrum of data providers related to groundwater. Due to the fact that data is produced and distributed by different types of organizations (national agencies, private companies, municipal water regulator, etc) the validation and cross check process is mandatory. The data is stored and managed by a geospatial database. The design of the database follows an object-orientated paradigm and is easily extensible. The third step consists of a set of procedures based on a multi criteria assessment that creates the specific setup for the thematic maps. The assessment is based on the following criteria: (1) scale effect , (2) time , (3) vertical distribution and (4) type of the groundwater related problem. The final

  10. Effects of Different Mineral Admixtures on the Properties of Fresh Concrete

    PubMed Central

    Nuruddin, Muhammad Fadhil; Shafiq, Nasir

    2014-01-01

    This paper presents a review of the properties of fresh concrete including workability, heat of hydration, setting time, bleeding, and reactivity by using mineral admixtures fly ash (FA), silica fume (SF), ground granulated blast furnace slag (GGBS), metakaolin (MK), and rice husk ash (RHA). Comparison of normal and high-strength concrete in which cement has been partially supplemented by mineral admixture has been considered. It has been concluded that mineral admixtures may be categorized into two groups: chemically active mineral admixtures and microfiller mineral admixtures. Chemically active mineral admixtures decrease workability and setting time of concrete but increase the heat of hydration and reactivity. On the other hand, microfiller mineral admixtures increase workability and setting time of concrete but decrease the heat of hydration and reactivity. In general, small particle size and higher specific surface area of mineral admixture are favourable to produce highly dense and impermeable concrete; however, they cause low workability and demand more water which may be offset by adding effective superplasticizer. PMID:24701196

  11. Effect of laminar air flow and clean-room dress on contamination rates of intravenous admixtures.

    PubMed

    Brier, K L; Latiolais, C J; Schneider, P J; Moore, T D; Buesching, W J; Wentworth, B C

    1981-08-01

    The effect of laminar air flow conditions and clean-room dress on the microbial contamination rates of intravenous admixtures was investigated. Intravenous admixtures were prepared by one investigator using aseptic technique under four environmental conditions: laminar air flow conditions with clean-room dress; laminar air flow without clean-room dress; clean table top with clean-room dress; and clean table top without clean-room dress. In each environmental condition, 350 admixtures were compounded. Negative-control samples (n = 150) were also tested, as were 10 positive-control samples. Samples were tested in each of two growth media and incubated at 35 degrees C for 14 days or until growth occurred. The incidence of contamination of admixtures compounded in laminar air flow conditions was significantly less than the contamination of those compounded on a clean table top (p less than 0.05) regardless of the operator's dress. The incidence of contamination of admixtures compounded while wearing clean-room dress was not significantly different from those prepared while not wearing clean-room dress regardless of the environment in which the admixture was prepared. The overall low level of contamination [0.79% (11/1400)] was inconclusive regarding the effect of dress on the incidence of contamination when admixtures were prepared under LAF conditions. It is concluded that, when one adheres to aseptic technique, the environment in which admixtures are compounded is the most important variable affecting the microbial contamination rate.

  12. How important is intraspecific genetic admixture to the success of colonising populations?

    EPA Science Inventory

    Genetic admixture of divergent lineages is increasingly suspected to play an important role in the success of colonizing populations. This has become a particularly prominent theme in the literature on biological invasions, where admixture is now commonly proposed as an important...

  13. [Effect of admixture of betamethasone butyrate propionate ointment on preservative efficacy].

    PubMed

    Ohtani, Michiteru; Nakai, Tatsurou; Ohsawa, Kouji; Kim, Soan; Matsumoto, Mika; Etoh, Takafumi; Kariya, Satoru; Kanou, Syoujirou; Uchino, Katsuyoshi

    2002-12-01

    Twenty percent of dermatologists have experienced a separation of water or deterioration of topical corticosteroids mixed with commercially available ointments and/or creams. However, few investigations of this deterioration of admixtures have been reported. To assess the effects of preservatives in preventing microbial contamination of these admixtures, we attempted to investigate the concentration of preservative agents in admixtures and the microbial contamination of these admixtures with a topical corticosteroid ointment (Antebate). The concentration of parabens was reduced by half using an admixture of corticosteroid ointment with four types of moisturizing creams, Urepearl, Pastaronsoft, Hirudoid, and Hirudoidsoft. After a further 3 months, no decrease in parabens was seen. No microbial contamination was found in any admixture stored at room temperature for 1 week and touched two times daily with a finger. The concentration and ratio of the parabens in the aqueous phase and oil phase were entirely different in the admixtures before being centrifuged. The aqueous phase of the admixtures of the oil/water (O/W)-type emulsions of Urepearl and Hirudoid was not found to have microbial contamination immediately after being centrifuged. All aqueous phases stored at room temperature or in a refrigerator for 1 week and touched with a finger twice daily exhibited microbial contamination. These experiments demonstrated that O/W-type emulsions, in which the water easily separates from the bases, should be thoroughly mixed to prevent microbial contamination.

  14. Bayesian analysis of an admixture model with mutations and arbitrarily linked markers.

    PubMed

    Excoffier, Laurent; Estoup, Arnaud; Cornuet, Jean-Marie

    2005-03-01

    We introduce here a Bayesian analysis of a classical admixture model in which all parameters are simultaneously estimated. Our approach follows the approximate Bayesian computation (ABC) framework, relying on massive simulations and a rejection-regression algorithm. Although computationally intensive, this approach can easily deal with complex mutation models and partially linked loci, and it can be thoroughly validated without much additional computation cost. Compared to a recent maximum-likelihood (ML) method, the ABC approach leads to similarly accurate estimates of admixture proportions in the case of recent admixture events, but it is found superior when the admixture is more ancient. All other parameters of the admixture model such as the divergence time between parental populations, the admixture time, and the population sizes are also well estimated, unlike the ML method. The use of partially linked markers does not introduce any particular bias in the estimation of admixture, but ML confidence intervals are found too narrow if linkage is not specifically accounted for. The application of our method to an artificially admixed domestic bee population from northwest Italy suggests that the admixture occurred in the last 10-40 generations and that the parental Apis mellifera and A. ligustica populations were completely separated since the last glacial maximum.

  15. Electricity Consumption Risk Map - The use of Urban Climate Mapping for smarter analysis: Case study for Birmingham, UK.

    NASA Astrophysics Data System (ADS)

    Antunes Azevedo, Juliana; Burghardt, René; Chapman, Lee; Katzchner, Lutz; Muller, Catherine L.

    2015-04-01

    Climate is a key driving factor in energy consumption. However, income, vegetation, building mass structure, topography also impact on the amount of energy consumption. In a changing climate, increased temperatures are likely to lead to increased electricity consumption, affecting demand, distribution and generation. Furthermore, as the world population becomes more urbanized, increasing numbers of people will need to deal with not only increased temperatures from climate change, but also from the unintentional modification of the urban climate in the form of urban heat islands. Hence, climate and climate change needs to be taken into account for future urban planning aspects to increase the climate and energy resilience of the community and decrease the future social and economic costs. Geographical Information Systems provide a means to create urban climate maps as part of the urban planning process. Geostatistical analyses linking these maps with demographic and social data, enables a geo-statistical analysis to identify linkages to high-risk groups of the community and vulnerable areas of town and cities. Presently, the climatope classification is oriented towards thermal aspects and the ventilation quality (roughness) of the urban areas but can also be adapted to take into account other structural "environmental factors". This study aims to use the climatope approach to predict areas of potential high electricity consumption in Birmingham, UK. Several datasets were used to produce an average surface temperature map, vegetation map, land use map, topography map, building height map, built-up area roughness calculations, an average air temperature map and a domestic electricity consumption map. From the correlations obtained between the layers it is possible to average the importance of each factor and create a map for domestic electricity consumption to understand the influence of environmental aspects on spatial energy consumption. Based on these results city

  16. Urban ergonomics: an ongoing study of city signs and maps.

    PubMed

    Alves, Patricia; Arezes, Pedro

    2012-01-01

    The purpose of this study is to assess whether the existing signals in three European cities were developed according usability principles and ergonomic aspects for the citizen. City maps and signals will be tested using efficiency, effectiveness and user's satisfaction criteria. Among the urban areas are the center of Paris-FR, assumed to be well signalized, the historical center of Guimarães-PT and Chorweiler, Cologne-DE, a residential neighborhood of modern urbanism characterized by the extensive use of vegetation, the landscape homogeneity, and, consequently, by the difficult navigation.

  17. The Emerging Role of Admixture in the Pharmacogenetics of Puerto Rican Hispanics

    PubMed Central

    Duconge, Jorge; Ruaño, Gualberto

    2011-01-01

    Admixture is of great relevance to the clinical application of pharmacogenetics and personalized medicine. Preliminary findings in Puerto Ricans further substantiate the argument for admixture as a critical covariate in a customized DNA-guided warfarin dosing algorithm. To this purpose, a genome-wide approach that incorporates admixture as an independent predictor of dose variability in DNA-guided algorithms has been postulated. Admixture is expected to be able to reveal some relevant associations in the genetic epidemiology of Hispanics and will be indispensable to assure that pharmacogenomic research can be pursued in such mixed populations. Consequently, the clinical utility of knowing an individual’s genotype before initiating drug treatment in Puerto Ricans, and Hispanics in general, will finally be untangled by developing a “Genetic Prescription Model” that takes admixture into consideration. This approach will help lead physicians and patients to their desired treatment goal, resulting in more effective healthcare in admixed people. PMID:23227441

  18. Comparative EEG mapping studies in Huntington's disease patients and controls.

    PubMed

    Painold, Annamaria; Anderer, Peter; Holl, Anna K; Letmaier, Martin; Saletu-Zyhlarz, Gerda M; Saletu, Bernd; Bonelli, Raphael M

    2010-11-01

    Huntington's disease (HD) is a devastating neurodegenerative disorder with prominent motor and cognitive decline. Previous studies with small sample sizes and methodological limitations have described abnormal electroencephalograms (EEG) in this cohort. The aim of the present study was to investigate objectively and quantitatively the neurophysiological basis of the disease in HD patients as compared to normal controls, utilizing EEG mapping. In 55 HD patients and 55 healthy controls, a 3-min vigilance-controlled EEG (V-EEG) was recorded during midmorning hours. Evaluation of 36 EEG variables was carried out by spectral analysis and visualized by EEG mapping techniques. To elucidate drug interference, the analysis was performed for the total group, unmedicated patients only and between treated and untreated patients. Statistical overall analysis by the omnibus significance test demonstrated significant (p < 0.01 and p < 0.05) EEG differences between HD patients and controls. Subsequent univariate analysis revealed a general decrease in total power and absolute alpha and beta power, an increase in delta/theta power, and a slowing of the centroids of delta/theta, beta and total power. The slowing of the EEG in HD reflects a disturbed brain function in the sense of a vigilance decrement, electrophysiologically characterized by inhibited cortical areas (increased delta/theta power) and a lack of normal routine and excitatory activity (decreased alpha and beta power). The results are similar to those found in other dementing disorders. Medication did not affect the overall interpretation of the quantitative EEG analysis, but certain differences might be due to drug interaction, predominantly with antipsychotics. Spearman rank correlations revealed significant correlations between EEG mapping and cognitive and motor impairment in HD patients.

  19. 78 FR 76888 - MAP-21 Comprehensive Truck Size and Weight Limits Study Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-19

    ... Federal Highway Administration MAP-21 Comprehensive Truck Size and Weight Limits Study Materials AGENCY... for Progress in the 21st Century Act (MAP-21) Comprehensive Truck Size and Weight Limits Study, which... public meetings on the MAP-21 Comprehensive Truck Size and Weight Limits Study and to announce...

  20. A Probabilistic Approach for Improved Sequence Mapping in Metatranscriptomic Studies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mapping millions of short DNA sequences a reference genome is a necessary step in many experiments designed to investigate the expression of genes involved in disease resistance. This is a difficult task in which several challenges often arise resulting in a suboptimal mapping. This mapping process ...

  1. Human genetic mapping studies using single sperm typing

    SciTech Connect

    Hubert, R.S.

    1993-01-01

    Sperm typing is a powerful technique that uses the polymerase chain reaction (PCR) to analyze DNA sequences within single sperm cells in order to construct genetic maps. This methodology was used to estimate the recombination fraction between D3S2 and D3S2 which was found to be 0.28 (95% CI = 0.20-0.36). Pedigree analysis was unable to determine genetic distance between these two markers due to their low informativeness. We also showed that dinucleotide and tetranucleotide repeat polymorphisms can be analyzed in single cells without using radioactivity or denaturing gels. This provides a rich new source of DANA polymorphisms for genetic mapping by sperm typing. In addition, an approach that uses the sperm typing methodology is described that can define the physical boundaries of meiotic recombination hotspots. The hotspot at 4p16.3 near the Huntington disease gene was localized to an interval between D4S10 and D4S126. These studies demonstrated the usefulness of sperm typing as a tool for the study of human genetic.

  2. Initial results of the Global Thermospheric Mapping Study (GTMS)

    NASA Technical Reports Server (NTRS)

    Oliver, W. L.; Salah, J. E.; Musgrove, R. G.; Holt, J. M.; Wickwar, V. B.; Hernandez, G. J.; Roble, R. G.

    1986-01-01

    The Global Thermospheric Mapping Study (GTMS) is a multi-technique experimental study of the thermosphere designed to map simultaneously its spatial and temporal morphology with a thoroughness and diversity of measurement techniques heretofore unachieved. The GTMS is designed around the Incoherent Scatter Radar Chain in the western hemisphere. The European incoherent scatter radars and the worldwide communities of Fabry-Perot interferometers, meteor wind radars, partial reflection drifts radars, MST radars, and satellite probes are included to extend the spatial coverage and types of measurements available. Theoretical and modeling support in the areas of thermospheric and ionospheric structure, tides, and electric fields are included to aid in program planning and data interpretation. Solar activity was low on the three observation days (F10.7 = 97, 98, 96) and magnetic conditions were unsettled to active (A = 10, 12, 20). All six incoherent scatter radar facilities collected data. Each collected F region data day and night while Saint Santin and Millstone Hill additionally collected E region data during daylight hours. Initial results from Sondrestrom and Millstone Hill are presented. Good quality Fabry Perot data were collected at Fritz Peak and San Jose dos Campos. Weather conditions produced poor results at Arequipa and Arecibo. Initial results from Fritz Peak are presented. Mesosphere/lower-thermosphere observations were conducted under the ATMAP organization. The magnetometer chains also were operational during this campaign. Initial thermospheric general circulation model predictions were made for assumed solar-geophysical conditions, and selected results are presented.

  3. Impact of admixtures on the hydration kinetics of Portland cement

    SciTech Connect

    Cheung, J.; Jeknavorian, A.; Roberts, L.; Silva, D.

    2011-12-15

    Most concrete produced today includes either chemical additions to the cement, chemical admixtures in the concrete, or both. These chemicals alter a number of properties of cementitious systems, including hydration behavior, and it has been long understood by practitioners that these systems can differ widely in response to such chemicals. In this paper the impact on hydration of several classes of chemicals is reviewed with an emphasis on the current understanding of interactions with cement chemistry. These include setting retarders, accelerators, and water reducing dispersants. The ability of the chemicals to alter the aluminate-sulfate balance of cementitious systems is discussed with a focus on the impact on silicate hydration. As a key example of this complex interaction, unusual behavior sometimes observed in systems containing high calcium fly ash is highlighted.

  4. New Faults Map Study for Central Part of Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Bin Fayez, A.

    2006-05-01

    The Institute of Astronomy and Geophysics Research at King Abdulaziz City for Science and Technology installed nine earthquake portable stations in central part of Saudi Arabia around Riyadh city to record micro- seismicty that is caused by local faults. Riyadh city and central part of Saudi Arabia are located in the Arabian Plate, which is known as a relatively stable platform. However, we have been able to determine some events that was caused by local faults. Most of these events are not felt. We are using digital recorders (RefTek 72A) for data acquisition and SAISAN software for analyses. The velocity model that I have used in this study is IASPEI model. Currently I am developing a map that shows some micro-earthquake events for that region. In addition, it includes some regional events. The objective of this study is to define the active faults in central part of Saudi Arabia.

  5. Alkali-silica reactions of mortars produced by using waste glass as fine aggregate and admixtures such as fly ash and Li2CO3.

    PubMed

    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.

  6. Population differentiation of zander (Sander lucioperca) across native and newly colonized ranges suggests increasing admixture in the course of an invasion

    PubMed Central

    Eschbach, Erik; Nolte, Arne W; Kohlmann, Klaus; Kersten, Petra; Kail, Jochem; Arlinghaus, Robert

    2014-01-01

    In addition to ecological factors, evolutionary processes can determine the invasion success of a species. In particular, genetic admixture has the potential to induce rapid evolutionary change, which can result from natural or human-assisted secondary contact between differentiated populations. We studied the recent range expansion of zander in Germany focusing on the interplay between invasion and genetic admixture. Historically, the rivers Elbe and Danube harboured the most north-western source populations from which a north-westward range expansion occurred. This was initiated by introducing zander outside its native range into rivers and lakes, and was fostered by migration through artificial canals and stocking from various sources. We analysed zander populations of the native and invaded ranges using nuclear and mitochondrial genetic markers. Three genetic lineages were identified, which were traced to ancestral ranges. Increased genetic diversity and admixture in the invaded region highlighted asymmetric gene flow towards this area. We suppose that the adaptive potential of the invading populations was promoted by genetic admixture, whereas competitive exclusion in the native areas provided a buffer against introgression by novel genotypes. These explanations would be in line with evidence that hybridization can drive evolutionary change under conditions when new niches can be exploited. PMID:24944569

  7. Assessing interethnic admixture using an X-linked insertion-deletion multiplex.

    PubMed

    Ribeiro-Rodrigues, Elzemar Martins; dos Santos, Ney Pereira Carneiro; dos Santos, Andrea Kely Campos Ribeiro; Pereira, Rui; Amorim, António; Gusmão, Leonor; Zago, Marco Antonio; dos Santos, Sidney Emanuel Batista

    2009-01-01

    In this study, a PCR multiplex was optimized, allowing the simultaneous analysis of 13 X-chromosome Insertion/deletion polymorphisms (INDELs). Genetic variation observed in Africans, Europeans, and Native Americans reveals high inter-population variability. The estimated proportions of X-chromosomes in an admixed population from the Brazilian Amazon region show a predominant Amerindian contribution (approximately 41%), followed by European (approximately 32%) and African (approximately 27%) contributions. The proportion of Amerindian contribution based on X-linked data is similar to the expected value based on mtDNA and Y-chromosome information. The accuracy for assessing interethnic admixture, and the high differentiation between African, European, and Native American populations, demonstrates the suitability of this INDEL set to measure ancestry proportions in three-hybrid populations, as it is the case of Latin American populations.

  8. Global prostate cancer incidence and the migration, settlement, and admixture history of the Northern Europeans

    PubMed Central

    Gunderson, Kristin; Wang, Christopher Y.; Wang, Ruoxiang

    2012-01-01

    The most salient feature of prostate cancer is its striking ethnic disparity. High incidences of the disease are documented in two ethnic groups: descendents of the Northern Europeans and African Americans. Other groups, including native Africans, are much less susceptible to the disease. Given that many risk factors may contribute to carcinogenesis, an etiological cause for the ethnic disparity remains to be defined. By analyzing the global prostate cancer incidence data, we found that distribution of prostate cancer incidence coincides with the migration and settlement history of Northern Europeans. The incidences in other ethnic groups correlate to the settlement history and extent of admixture of the Europeans. This study suggests that prostate cancer has been spread by the transmission of a genetic susceptibility that resides in the Northern European genome. PMID:21167803

  9. Comparison of the physicochemical properties of MCT-containing fat emulsions in total nutrient admixtures.

    PubMed

    Télessy, I G; Balogh, J; Csempesz, F; Szente, V; Dredán, J; Zelkó, R

    2009-08-01

    The physical stability of two types of MCT-emulsions made by different technologies - physical mixture vs. structured lipids - was studied as a function of storage time and temperature. Particle size analysis, zeta potential and dynamic surface tension measurements were carried out to evaluate the possible changes in the kinetic stability of the emulsions. Our results indicate that the physical mixture technology of MCT-emulsions resulted in impaired physicochemical stability compared to the ones containing structured triglycerides. In the case of structured lipids, both medium and long chain fatty acids can be found in one triglyceride molecule, leading to a favorable interfacial location of structured triglycerides. Besides the advantageous metabolic effects of structured triglycerides, their application is recommended to improve the physical stability of TPN admixtures.

  10. Origin and dynamics of admixture in Brazilians and its effect on the pattern of deleterious mutations.

    PubMed

    Kehdy, Fernanda S G; Gouveia, Mateus H; Machado, Moara; Magalhães, Wagner C S; Horimoto, Andrea R; Horta, Bernardo L; Moreira, Rennan G; Leal, Thiago P; Scliar, Marilia O; Soares-Souza, Giordano B; Rodrigues-Soares, Fernanda; Araújo, Gilderlanio S; Zamudio, Roxana; Sant Anna, Hanaisa P; Santos, Hadassa C; Duarte, Nubia E; Fiaccone, Rosemeire L; Figueiredo, Camila A; Silva, Thiago M; Costa, Gustavo N O; Beleza, Sandra; Berg, Douglas E; Cabrera, Lilia; Debortoli, Guilherme; Duarte, Denise; Ghirotto, Silvia; Gilman, Robert H; Gonçalves, Vanessa F; Marrero, Andrea R; Muniz, Yara C; Weissensteiner, Hansi; Yeager, Meredith; Rodrigues, Laura C; Barreto, Mauricio L; Lima-Costa, M Fernanda; Pereira, Alexandre C; Rodrigues, Maíra R; Tarazona-Santos, Eduardo

    2015-07-14

    While South Americans are underrepresented in human genomic diversity studies, Brazil has been a classical model for population genetics studies on admixture. We present the results of the EPIGEN Brazil Initiative, the most comprehensive up-to-date genomic analysis of any Latin-American population. A population-based genome-wide analysis of 6,487 individuals was performed in the context of worldwide genomic diversity to elucidate how ancestry, kinship, and inbreeding interact in three populations with different histories from the Northeast (African ancestry: 50%), Southeast, and South (both with European ancestry >70%) of Brazil. We showed that ancestry-positive assortative mating permeated Brazilian history. We traced European ancestry in the Southeast/South to a wider European/Middle Eastern region with respect to the Northeast, where ancestry seems restricted to Iberia. By developing an approximate Bayesian computation framework, we infer more recent European immigration to the Southeast/South than to the Northeast. Also, the observed low Native-American ancestry (6-8%) was mostly introduced in different regions of Brazil soon after the European Conquest. We broadened our understanding of the African diaspora, the major destination of which was Brazil, by revealing that Brazilians display two within-Africa ancestry components: one associated with non-Bantu/western Africans (more evident in the Northeast and African Americans) and one associated with Bantu/eastern Africans (more present in the Southeast/South). Furthermore, the whole-genome analysis of 30 individuals (42-fold deep coverage) shows that continental admixture rather than local post-Columbian history is the main and complex determinant of the individual amount of deleterious genotypes.

  11. Origin and dynamics of admixture in Brazilians and its effect on the pattern of deleterious mutations

    PubMed Central

    Kehdy, Fernanda S. G.; Gouveia, Mateus H.; Machado, Moara; Magalhães, Wagner C. S.; Horimoto, Andrea R.; Horta, Bernardo L.; Moreira, Rennan G.; Leal, Thiago P.; Scliar, Marilia O.; Soares-Souza, Giordano B.; Rodrigues-Soares, Fernanda; Araújo, Gilderlanio S.; Zamudio, Roxana; Sant Anna, Hanaisa P.; Santos, Hadassa C.; Duarte, Nubia E.; Fiaccone, Rosemeire L.; Figueiredo, Camila A.; Silva, Thiago M.; Costa, Gustavo N. O.; Beleza, Sandra; Berg, Douglas E.; Cabrera, Lilia; Debortoli, Guilherme; Duarte, Denise; Ghirotto, Silvia; Gilman, Robert H.; Gonçalves, Vanessa F.; Marrero, Andrea R.; Muniz, Yara C.; Weissensteiner, Hansi; Yeager, Meredith; Rodrigues, Laura C.; Barreto, Mauricio L.; Lima-Costa, M. Fernanda; Pereira, Alexandre C.; Rodrigues, Maíra R.; Tarazona-Santos, Eduardo

    2015-01-01

    While South Americans are underrepresented in human genomic diversity studies, Brazil has been a classical model for population genetics studies on admixture. We present the results of the EPIGEN Brazil Initiative, the most comprehensive up-to-date genomic analysis of any Latin-American population. A population-based genome-wide analysis of 6,487 individuals was performed in the context of worldwide genomic diversity to elucidate how ancestry, kinship, and inbreeding interact in three populations with different histories from the Northeast (African ancestry: 50%), Southeast, and South (both with European ancestry >70%) of Brazil. We showed that ancestry-positive assortative mating permeated Brazilian history. We traced European ancestry in the Southeast/South to a wider European/Middle Eastern region with respect to the Northeast, where ancestry seems restricted to Iberia. By developing an approximate Bayesian computation framework, we infer more recent European immigration to the Southeast/South than to the Northeast. Also, the observed low Native-American ancestry (6–8%) was mostly introduced in different regions of Brazil soon after the European Conquest. We broadened our understanding of the African diaspora, the major destination of which was Brazil, by revealing that Brazilians display two within-Africa ancestry components: one associated with non-Bantu/western Africans (more evident in the Northeast and African Americans) and one associated with Bantu/eastern Africans (more present in the Southeast/South). Furthermore, the whole-genome analysis of 30 individuals (42-fold deep coverage) shows that continental admixture rather than local post-Columbian history is the main and complex determinant of the individual amount of deleterious genotypes. PMID:26124090

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

    PubMed

    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. No clear effect of admixture between two European invading outbreaks of Diabrotica virgifera virgifera in natura.

    PubMed

    Bermond, Gérald; Cavigliasso, Fanny; Mallez, Sophie; Spencer, Joseph; Guillemaud, Thomas

    2014-01-01

    In this study, we challenged the hypothesis that admixture may have had a positive impact in the context of the European invasion of the western corn rootworm (WCR), Diabrotica virgifera virgifera, LeConte. This beetle was introduced in Europe from the USA several times since the 1980's. The multiple introductions of this major pest of cultivated corn led to the formation of two major outbreaks in North Western (NW) Italy and in Central and South Eastern (CSE) Europe that eventually merged into a secondary contact zone where insects from both outbreaks interbreed. We collected about 600 insects from this contact zone and genotyped them using 13 microsatellite markers. Three types of information were obtained from the collected individuals: (i) their survival under starvation; (ii) their admixed status, determined through a Bayesian method of genetic clustering and (iii) their mating probability, studied via the detection, isolation and genotyping of sperm in female spermathecae. Twenty six % and 12% of the individuals were assigned to the NW Italy or the CSE Europe parental types, respectively, and 23% and 39% to the F1 and backcross hybrid types, respectively. Globally, our results do not reveal any significant impact of the admixed status on the mating probability and on the choice of mating partners. However the admixed status had a sex- and sampling site-dependent effect on survival in adults under starvation. In addition sex had an effect on survival, with mortality hazard about 3 times larger in males than in females. The consequences of these findings for the evolution of the admixture zone of northern Italy are discussed.

  14. Relationship between diabetes risk and admixture in postmenopausal African-American and Hispanic-American women

    PubMed Central

    Qi, L.; Nassir, R.; Kosoy, R.; Garcia, L.; Curb, J. D.; Tinker, L.; Howard, B. V.; Robbins, J.; Seldin, M. F.

    2015-01-01

    Aims/hypothesis Type 2 diabetes is more prevalent in African-Americans (AFAs) and Hispanic-Americans (HAs) than in European-Americans. We assessed whether continental admixture was correlated with diabetes risk in these high-risk groups. Methods We estimated the proportion of sub-Saharan African (AFR), Amerindian (AMI) and European admixture using 92 ancestry-informative marker genotypes in 16,476 AFA and HA women from the Women's Health Initiative. Cox regression models were used to examine the association between admixture and diabetes risk, with and without accounting for socioeconomic status (SES) and adiposity measurements. Results AFR admixture was significantly associated with diabetes risk in AFA women when adjusting for entry age, neighbourhood SES and BMI or waist/hip ratio (WHR) (all p<0.0001). In HA women, AMI admixture had significant associations with diabetes risk that remained significant after adjustment for SES and BMI (all p<0.0005). In both AFAs and HAs, SES showed significant negative associations while BMI or WHR had significant positive associations with diabetes risk, with and without adjustment for genetic admixture. Conclusions/interpretation In AFAs, admixture, SES and BMI/WHR each independently contribute to diabetes risk after accounting for each of the other factors; in HAs, admixture, SES and BMI each independently contribute to diabetes risk after accounting for each of the other factors, whereas admixture is not significantly associated with diabetes risk after accounting for SES and WHR. The findings emphasise the importance of considering both genetic and environmental causes in the aetiology of type 2 diabetes. PMID:22322919

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

    PubMed

    Verhoeven, Koen J F; Macel, Mirka; Wolfe, Lorne M; Biere, Arjen

    2011-01-07

    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 role in biological invasions. In contrast, populations in their native range often remain differentiated and frequently suffer from inbreeding depression owing to isolation. While the advantages of admixture are evident for introduced populations that experienced recent bottlenecks or that face novel selection pressures, it is less obvious why native range populations do not similarly benefit from admixture. Here we argue that a temporary loss of local adaptation in recent invaders fundamentally alters the fitness consequences of admixture. In native populations, selection against dilution of the locally adapted gene pool inhibits unconstrained admixture and reinforces population isolation, with some level of inbreeding depression as an expected consequence. We show that admixture is selected against despite significant inbreeding depression because the benefits of local adaptation are greater than the cost of inbreeding. In contrast, introduced populations that have not yet established a pattern of local adaptation can freely reap the benefits of admixture. There can be strong selection for admixture because it instantly lifts the inbreeding depression that had built up in isolated parental populations. Recent work in Silene suggests that reduced inbreeding depression associated with post-introduction admixture may contribute to enhanced fitness of invasive populations. We hypothesize that in locally adapted populations, the benefits of local adaptation are balanced against an inbreeding cost that could develop in part owing to the isolating effect of local adaptation itself. The inbreeding cost can be revealed in admixing populations during recent invasions.

  16. The JERS-1 Amazon Multi-Season Mapping Study (JAMMS)

    NASA Technical Reports Server (NTRS)

    Freeman, A.; Chapman, B.; Alves, M.

    1996-01-01

    Regional mapping of the Amazon basin using imaging radar is described. Two 60-day periods of radar mapping will be conducted, one in 1995, and one in 1996. One period will view the low-water season, and the other will view during the high-flood season. The main objective of the JAMMS project is to generate a regional map showing inundation throughout the Amazon Basin by comparing the two data sets.

  17. Doppler ultrasound study and venous mapping in chronic venous insufficiency.

    PubMed

    García Carriazo, M; Gómez de las Heras, C; Mármol Vázquez, P; Ramos Solís, M F

    2016-01-01

    Chronic venous insufficiency of the lower limbs is very prevalent. In recent decades, Doppler ultrasound has become the method of choice to study this condition, and it is considered essential when surgery is indicated. This article aims to establish a method for the examination, including venous mapping and preoperative marking. To this end, we review the venous anatomy of the lower limbs and the pathophysiology of chronic venous insufficiency and explain the basic hemodynamic concepts and the terminology required to elaborate a radiological report that will enable appropriate treatment planning and communication with other specialists. We briefly explain the CHIVA (the acronym for the French term "cure conservatrice et hémodynamique de l'insuffisance veineuse en ambulatoire"=conservative hemodynamic treatment for chronic venous insufficiency) strategy, a minimally invasive surgical strategy that aims to restore correct venous hemodynamics without resecting the saphenous vein.

  18. Photoinduced surface voltage mapping study for large perovskite single crystals

    NASA Astrophysics Data System (ADS)

    Liu, Xiaojing; Liu, Yucheng; Gao, Fei; Yang, Zhou; Liu, Shengzhong Frank

    2016-05-01

    Using a series of illumination sources, including white light (tungsten-halogen lamp), 445-nm, 532-nm, 635-nm, and 730-nm lasers, the surface photovoltage (SPV) images were mapped for centimeter-sized CH3NH3PbX3 (X = Cl, Br, I) perovskite single crystals using Kelvin probe force microscopy. The significant SPV signals were observed to be wavelength-dependent. We attribute the appreciable SPV to the built-in electric field in the space charge region. This study shines light into the understanding of photoinduced charge generation and separation processes at nanoscale to help advance the development of perovskite solar cells, optoelectronics, laser, photodetector, and light-emitting diode (LED).

  19. Land use mapping in Erie County, Pennsylvania: A pilot study

    NASA Technical Reports Server (NTRS)

    Mcmurtry, G. J.; Petersen, G. W. (Principal Investigator); May, G. A.

    1974-01-01

    The author has identified the following significant results. A pilot study was conducted to determine the feasibility of mapping land use in the Great Lakes Basin area utilizing ERTS-1 data. Small streams were clearly defined by the presence of trees along their length in predominantly agricultural country. Field patterns were easily differentiated from forested areas; dairy and beef farms were differentiated from other farmlands, but no attempt was made to identify crops. Large railroad lines and major highway systems were identified. The city of Erie and several smaller towns were identified, as well as residential areas between these towns, and docks along the shoreline in Erie. Marshes, forests, and beaches within Presque Isle State Park were correctly identified, using the DCLUS program. Bay water was differentiated from lake water, with a small amount of misclassification.

  20. Velocity Map Imaging Studies of Non-Conventional Methanethiol Photochemistry

    NASA Astrophysics Data System (ADS)

    Toulson, Benjamin W.; Alaniz, Jonathan; Murray, Craig

    2014-06-01

    Velocity map imaging (VMI) in combination with state-selective resonance enhanced multiphoton ionization (REMPI) has been used to study the photodissociation dynamics of methanethiol following excitation to the first and second singlet electronically excited states. Formation of sulfur atoms, in both the singlet and triplet manifolds, is observed and can be attributed to primary dissociation of the parent molecule. We will report the nascent photofragment velocity distributions, and hence the internal energy of the methane co-fragment. Sulfur atom quantum yields are benchmarked against a known standard to evaluate the significance of this pathway. The role of non-conventional photochemical mechanisms such as roaming-mediated intersystem crossing, previously observed in methylamine photochemistry, will be discussed. James O. Thomas, Katherine E. Lower, and Craig Murray, The Journal of Physical Chemistry Letters, 2012, 3 (10), 1341-1345.

  1. Hydration Characteristics of Metakaolin Admixtured Cement using DTA, XRD and SEM Techniques

    NASA Astrophysics Data System (ADS)

    Govindarajan, D.; Gopalakrishnan, R.

    2008-04-01

    The paper aims to investigate hydration and pozzolanic reaction in Portland cement paste with different replacement percentages (0%, 10%, 20% and 30%) of metakaolin. The compressive strength of the metakaolin admixtured cement was measured at 1 day, 1 week and 4 weeks. The compressive strength developments of the metakaolin admixtured cement are compared with Portland cement. It is found that metakaolin contributes significantly to strength development as an accelerating admixture for Portland cement. The pozzolanic reactions and the reaction products were determined by DTA, XRD and SEM.

  2. Detecting Ancient Admixture and Estimating Demographic Parameters in Multiple Human Populations

    PubMed Central

    Lohmueller, Kirk E.; Plagnol, Vincent

    2009-01-01

    We analyze patterns of genetic variation in extant human polymorphism data from the National Institute of Environmental Health Sciences single nucleotide polymorphism project to estimate human demographic parameters. We update our previous work by considering a larger data set (more genes and more populations) and by explicitly estimating the amount of putative admixture between modern humans and archaic human groups (e.g., Neandertals, Homo erectus, and Homo floresiensis). We find evidence for this ancient admixture in European, East Asian, and West African samples, suggesting that admixture between diverged hominin groups may be a general feature of recent human evolution. PMID:19420049

  3. Genetic origin, admixture and population history of aurochs (Bos primigenius) and primitive European cattle

    PubMed Central

    Upadhyay, M R; Chen, W; Lenstra, J A; Goderie, C R J; MacHugh, D E; Park, S D E; Magee, D A; Matassino, D; Ciani, F; Megens, H-J; van Arendonk, J A M; Groenen, M A M; Marsan, P A; Balteanu, V; Dunner, S; Garcia, J F; Ginja, C; Kantanen, J

    2017-01-01

    The domestication of taurine cattle initiated ~10 000 years ago in the Near East from a wild aurochs (Bos primigenius) population followed by their dispersal through migration of agriculturalists to Europe. Although gene flow from wild aurochs still present at the time of this early dispersion is still debated, some of the extant primitive cattle populations are believed to possess the aurochs-like primitive features. In this study, we use genome-wide single nucleotide polymorphisms to assess relationship, admixture patterns and demographic history of an ancient aurochs sample and European cattle populations, several of which have primitive features and are suitable for extensive management. The principal component analysis, the model-based clustering and a distance-based network analysis support previous works suggesting different histories for north-western and southern European cattle. Population admixture analysis indicates a zebu gene flow in the Balkan and Italian Podolic cattle populations. Our analysis supports the previous report of gene flow between British and Irish primitive cattle populations and local aurochs. In addition, we show evidence of aurochs gene flow in the Iberian cattle populations indicating wide geographical distribution of the aurochs. Runs of homozygosity (ROH) reveal that demographic processes like genetic isolation and breed formation have contributed to genomic variations of European cattle populations. The ROH also indicate recent inbreeding in southern European cattle populations. We conclude that in addition to factors such as ancient human migrations, isolation by distance and cross-breeding, gene flow between domestic and wild-cattle populations also has shaped genomic composition of European cattle populations. PMID:27677498

  4. Single Geographic Origin of a Widespread Autotetraploid Arabidopsis arenosa Lineage Followed by Interploidy Admixture.

    PubMed

    Arnold, Brian; Kim, Sang-Tae; Bomblies, Kirsten

    2015-06-01

    Whole-genome duplication, which leads to polyploidy, has been implicated in speciation and biological novelty. In plants, many species exhibit ploidy variation, which is likely representative of an early stage in the evolution of polyploid lineages. To understand the evolution of such multiploidy systems, we must address questions such as whether polyploid lineage(s) had a single or multiple origins, whether admixture occurs between ploidies, and the timescale over which ploidy variation affects the evolution of populations. Here we analyze three genomic data sets using nonparametric and parametric analyses, including coalescent-based methods, to study the evolutionary history of a geographically widespread autotetraploid variant of Arabidopsis arenosa, a new model system for understanding the molecular basis of autopolyploid evolution. Autotetraploid A. arenosa populations are widely distributed across much of Northern and Central Europe, whereas diploids occur in Eastern Europe and along the southern Baltic coast; the two ploidies overlap in the Carpathian Mountains. We find that the widespread autotetraploid populations we sampled likely arose from a single ancestral population approximately 11,000-30,000 generations ago in the Northern Carpathians, where its closest extant diploid relatives are found today. Afterward, the tetraploid population split into at least four major lineages that colonized much of Europe. Reconstructions of population history suggest that substantial interploidy admixture occurred in both directions, but only among geographically proximal populations. We find two cases in which selection likely acted on an introgressed locus, suggesting that persistent interploidy gene flow has a local influence on patterns of genetic variation in A. arenosa.

  5. Admixture and population structure in Mexican-Mestizos based on paternal lineages.

    PubMed

    Martínez-Cortés, Gabriela; Salazar-Flores, Joel; Fernández-Rodríguez, Laura Gabriela; Rubi-Castellanos, Rodrigo; Rodríguez-Loya, Carmen; Velarde-Félix, Jesús Salvador; Muñoz-Valle, José Franciso; Parra-Rojas, Isela; Rangel-Villalobos, Héctor

    2012-09-01

    In the nonrecombining region of the Y-chromosome, there are single-nucleotide polymorphisms (Y-SNPs) that establish haplogroups with particular geographical origins (European, African, Native American, etc.). The complex process of admixture that gave rise to the majority of the current Mexican population (~93%), known as Mestizos, can be examined with Y-SNPs to establish their paternal ancestry and population structure. We analyzed 18 Y-SNPs in 659 individuals from 10 Mexican-Mestizo populations from different regions of the country. In the total population sample, paternal ancestry was predominately European (64.9%), followed by Native American (30.8%) and African (4.2%). However, the European ancestry was prevalent in the north and west (66.7-95%) and, conversely, Native American ancestry increased in the center and southeast (37-50%), whereas the African ancestry was low and relatively homogeneous (0-8.8%). Although this paternal landscape concurs with previous studies based on genome-wide SNPs and autosomal short tandem repeats (STRs), this pattern contrasts with the maternal ancestry, mainly of Native American origin, based on maternal lineages haplogroups. In agreement with historical records, these results confirm a strong gender-biased admixture history between European males and Native American females that gave rise to Mexican-Mestizos. Finally, pairwise comparisons and analysis of molecular variance tests demonstrated significant population structure (F(ST)=4.68%; P<0.00005), delimiting clusters that were geographically defined as the following: north-west, center-south and southeast.

  6. The JERS Amazon Multi-Season Mapping Study (JAMMS): Observation Strategies and Data Characteristics

    NASA Technical Reports Server (NTRS)

    Chapman, B.; Freeman, A.; Siqueira, P.

    2000-01-01

    The JERS-1 Amazon Multi-season Mapping Study (JAMMS), part of the Global Rain Forest Mapping (GRFM) project led by the National Space Development Agency of Japan (NASDA), had an ambitious agenda to completely map the Amazon River floodpain (and surrounding areas) twice at high resolution.

  7. A STUDY OF THE EFFECTS OF POST-COMBUSTION AMMONIA INJECTION ON FLY ASH QUALITY: CHARACTERIZATION OF AMMONIA RELEASE FROM CONCRETE AND MORTARS CONTAINING FLY ASH AS A POZZOLANIC ADMIXTURE

    SciTech Connect

    Robert F. Rathbone; Thomas L. Robl

    2002-10-30

    The Clean Air Act Amendments of 1990 require large reductions in emissions of NO{sub x} from coal-fired electric utility boilers. This will necessitate the use of ammonia injection, such as in selective catalytic reduction (SCR), in many power plants, resulting in the deposition of ammonia on the fly ash. The presence of ammonia could create a major barrier to fly ash utilization in concrete because of odor concerns. Although there have been limited studies of ammonia emission from concrete, little is known about the quantity of ammonia emitted during mixing and curing, and the kinetics of ammonia release. This is manifested as widely varying opinions within the concrete and ash marketing industry regarding the maximum acceptable levels of ammonia in fly ash. Therefore, practical guidelines for using ammoniated fly ash are needed in advance of the installation of many more SCR systems. The goal of this project was to develop practical guidelines for the handling and utilization of ammoniated fly ash in concrete, in order to prevent a decrease in the use of fly ash for this application. The objective was to determine the amount of ammonia that is released, over the short- and long-term, from concrete that contains ammoniated fly ash. The technical approach in this project was to measure the release of ammonia from mortar and concrete during mixing, placement, and curing. Work initially focused on laboratory mortar experiments to develop fundamental data on ammonia diffusion characteristics. Larger-scale laboratory experiments were then conducted to study the emission of ammonia from concrete containing ammoniated fly ash. The final phase comprised monitoring ammonia emissions from large concrete slabs. The data indicated that, on average, 15% of the initial ammonia was lost from concrete during 40 minutes of mixing, depending on the mix proportions and batch size. Long-term experiments indicated that ammonia diffusion from concrete was relatively slow, with greater

  8. A STUDY OF THE EFFECTS OF POST-COMBUSTION AMMONIA INJECTION ON FLY ASH QUALITY: CHARACTERIZATION OF AMMONIA RELEASE FROM CONCRETE AND MORTARS CONTAINING FLY ASH AS A POZZOLANIC ADMIXTURE

    SciTech Connect

    Robert F. Rathbone; Thomas L. Robl

    2002-04-11

    Work completed in this reporting period focused primarily on continuing measurements of the rate of ammonia loss from concrete, and the measurement of ammonia gas in the air above concrete and flowable fill immediately after placement. Concrete slabs were prepared to monitor the loss of ammonia during mixing, the concentration in the airspace above the slabs soon after placement, and the total quantity of ammonia evolved over a longer time period. Variables tested include temperature, ventilation rate, water:cementitious (W:C) ratio, and fly ash source. Short-term data indicate that for concrete placed in areas with poor air ventilation the fly ash NH{sub 3} concentration should not exceed about 90 to 145 mg/kg ash, depending on the water:cement ratio and the fly ash replacement rate, if a concentration of 10 ppm NH{sub 3} in the air is assumed to be the maximum acceptable level. Longer-term experiments showed that the ammonia loss rate is dependent on ammonia source (that is ammoniated ash vs. non-ammoniated ash with ammonia added to the water), and is also dependent on W:C ratio and temperature. Experiments were also conducted to study the loss of ammonia from fresh concrete during mixing. It was found that a high water:cementitious mix lost a greater percentage of ammonia than a low W:C mix, with a medium W:C mix losing an amount intermediate between these two. However, a larger batch size resulted in a smaller percentage of ammonia lost. The data suggest that a significant quantity of ammonia could be lost from Ready Mix concrete during transit, depending on the transit time, batch size, and mix proportions.

  9. Circulating Endocannabinoids and the Polymorphism 385C>A in Fatty Acid Amide Hydrolase (FAAH) Gene May Identify the Obesity Phenotype Related to Cardiometabolic Risk: A Study Conducted in a Brazilian Population of Complex Interethnic Admixture.

    PubMed

    Martins, Cyro José de Moraes; Genelhu, Virginia; Pimentel, Marcia Mattos Gonçalves; Celoria, Bruno Miguel Jorge; Mangia, Rogerio Fabris; Aveta, Teresa; Silvestri, Cristoforo; Di Marzo, Vincenzo; Francischetti, Emilio Antonio

    2015-01-01

    The dysregulation of the endocannabinoid system is associated with cardiometabolic complications of obesity. Allelic variants in coding genes for this system components may contribute to differences in the susceptibility to obesity and related health hazards. These data have mostly been shown in Caucasian populations and in severely obese individuals. We investigated a multiethnic Brazilian population to study the relationships among the polymorphism 385C>A in an endocannabinoid degrading enzyme gene (FAAH), endocannabinoid levels and markers of cardiometabolic risk. Fasting plasma levels of endocannabinoids and congeners (anandamide, 2-arachidonoylglycerol, N-oleoylethanolamide and N-palmitoylethanolamide) were measured by liquid chromatography-mass spectrometry in 200 apparently healthy individuals of both genders with body mass indices from 22.5 ± 1.8 to 35.9 ± 5.5 kg/m2 (mean ± 1 SD) and ages between 18 and 60 years. All were evaluated for anthropometric parameters, blood pressure, metabolic variables, homeostatic model assessment of insulin resistance (HOMA-IR), adiponectin, leptin, C-reactive protein, and genotyping. The endocannabinoid levels increased as a function of obesity and insulin resistance. The homozygous genotype AA was associated with higher levels of anandamide and lower levels of adiponectin versus wild homozygous CC and heterozygotes combined. The levels of anandamide were independent and positively associated with the genotype AA position 385 of FAAH, C-reactive protein levels and body mass index. Our findings provide evidence for an endocannabinoid-related phenotype that may be identified by the combination of circulating anandamide levels with genotyping of the FAAH 385C>A; this phenotype is not exclusive to mono-ethnoracial populations nor to individuals with severe obesity.

  10. Circulating Endocannabinoids and the Polymorphism 385C>A in Fatty Acid Amide Hydrolase (FAAH) Gene May Identify the Obesity Phenotype Related to Cardiometabolic Risk: A Study Conducted in a Brazilian Population of Complex Interethnic Admixture

    PubMed Central

    Martins, Cyro José de Moraes; Genelhu, Virginia; Pimentel, Marcia Mattos Gonçalves; Celoria, Bruno Miguel Jorge; Mangia, Rogerio Fabris; Aveta, Teresa; Silvestri, Cristoforo; Di Marzo, Vincenzo; Francischetti, Emilio Antonio

    2015-01-01

    The dysregulation of the endocannabinoid system is associated with cardiometabolic complications of obesity. Allelic variants in coding genes for this system components may contribute to differences in the susceptibility to obesity and related health hazards. These data have mostly been shown in Caucasian populations and in severely obese individuals. We investigated a multiethnic Brazilian population to study the relationships among the polymorphism 385C>A in an endocannabinoid degrading enzyme gene (FAAH), endocannabinoid levels and markers of cardiometabolic risk. Fasting plasma levels of endocannabinoids and congeners (anandamide, 2-arachidonoylglycerol, N-oleoylethanolamide and N-palmitoylethanolamide) were measured by liquid chromatography-mass spectrometry in 200 apparently healthy individuals of both genders with body mass indices from 22.5 ± 1.8 to 35.9 ± 5.5 kg/m2 (mean ± 1 SD) and ages between 18 and 60 years. All were evaluated for anthropometric parameters, blood pressure, metabolic variables, homeostatic model assessment of insulin resistance (HOMA-IR), adiponectin, leptin, C-reactive protein, and genotyping. The endocannabinoid levels increased as a function of obesity and insulin resistance. The homozygous genotype AA was associated with higher levels of anandamide and lower levels of adiponectin versus wild homozygous CC and heterozygotes combined. The levels of anandamide were independent and positively associated with the genotype AA position 385 of FAAH, C-reactive protein levels and body mass index. Our findings provide evidence for an endocannabinoid-related phenotype that may be identified by the combination of circulating anandamide levels with genotyping of the FAAH 385C>A; this phenotype is not exclusive to mono-ethnoracial populations nor to individuals with severe obesity. PMID:26561012

  11. Chemical Stability of Admixtures Containing Ziconotide 25 mcg/mL and Morphine Sulfate 10 mg/mL or 20 mg/mL During Simulated Intrathecal Administration.

    PubMed

    Shields, David E; Aclan, Jennifer; Szatkowski, Aaron

    2008-01-01

    The chemical stability of an intrathecally administered analgesic combination may influence the frequency of pump refills necessary to maintain safe and effective analgesia. Previous work has shown that the stability of ziconotide at body temperature is reduced substantially by the presence of morphine sulfate 35 mg/mL. The current study was performed to evaluate the chemical stability of admixtures combining ziconotide with lower concentrations of morphine sulfate during simulated intrathecal infusion under laboratory conditions at 37 deg C. Admixtures containing ziconotide 25 mcg/mL and morphine sulfate 10 mg/mL or 20 mg/mL were stored in implantable intrathecal pumps at 37 deg C and in control vials at 37 deg C or 5 deg C. Samples were obtained over 60 days (admixture containing morphine sulfate 10 mg/mL) or 28 days (admixture containing morphine sulfate 20 mg/mL) and drug concentrations were assessed by high-performance liquid chromatography. Estimates of the time intervals that each admixture retained > or= 90% and > or = 80% of the initial concentrations of both drugs (i.e., the 90% and 80% stabilites) were based on 95% confidence bounds obtained via linear regression. Morphine sulfate 10 mg/mL, the mean ziconotide concentration declined to 81.4% of the initial concentration in 60 days, and 90% and 80% stabilites were maintained for 34 days and 65 days, respctively. In the admixture containing morphine sulfate 20 mg/mL, the mean ziconotide concentration declined to 85.3% of the initial concentration in 28 days, and 90% and 80% stabilities were maintained for 19 days and 37 days, respectively. Decreasing the concentration of morphine in an admixture containing ziconotide improves the stablity of ziconotide.

  12. Robust inference of genetic architecture in mapping studies.

    PubMed

    Slate, Jon

    2017-03-01

    The genetic architecture of a trait usually refers to the number and magnitude of loci that explain phenotypic variation. A description of genetic architecture can help us to understand how genetic variation is maintained, how traits have evolved and how phenotypes might respond to selection. However, linkage mapping and association studies can suffer from problems of bias, especially when conducted in natural populations where the opportunity to perform studies with very large sample sizes can be limited. In this issue of Molecular Ecology, Li and colleagues perform an association study of brain traits in ninespine sticklebacks Pungitius pungitius. They use a sophisticated approach that models all of the genotyped markers simultaneously; conventional approaches fit each marker individually. Although the single-marker and multi-marker approaches find similar regions of the genome that explain phenotypic variation, the overall conclusions about trait architecture are somewhat different, depending on the approach used. Single-marker methods identify regions that explain quite large proportions of genetic variation, whereas the multi-marker approach suggests the traits are far more polygenic. Simulations suggest the multi-marker approach is robust. This study highlights how molecular quantitative genetics in wild populations can be used to address hypothesis-driven questions, without making unrealistic assumptions about effect sizes of individual quantitative trait loci.

  13. Influence of nonisothermicity of the medium and polymer admixtures on a turbulent vertical wall jet

    NASA Astrophysics Data System (ADS)

    Pokryvailo, N. A.; Shashmin, V. K.; Shul'Man, Z. P.

    1990-04-01

    The results are given on an experimental investigation of the effect of small polymer admixtures and density inhomogeneity of the ambient medium on the laws of development of plane, vertical, turbulent wall jets.

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

    PubMed Central

    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. Evaluation of Admixtures for Use in Concrete to be Placed Underwater.

    DTIC Science & Technology

    1976-09-01

    tremie method. The tremie used consisted of a pipe topped with a receiving funnel and plugged at the discharge end to keep the pipe sealed until filled ...to determine if these commercially available admixtures when used in concrete to be placed underwater increase the flowability of the concrete. Test...results indicated that the use of either a retarding admixture or a plasticizer did not increase the flowability of equal-slump concrete, regardless of

  16. Effects of a midazolam-ketamine admixture in human volunteers.

    PubMed

    Morse, Zac; Sano, Kimito; Kanri, Tomio

    2004-01-01

    As the ideal sedative does not exist for all situations, we examined the effect of a midazolam-ketamine sedoanalgesic admixture in human volunteers. Ten ASA physical status I volunteers were administered loading doses of 0.07 mg/kg of midazolam followed by 0.7 mg/kg of ketamine. The same amount of midazolam and ketamine was then infused constantly over 1 hour via a 60 drops (gtts)/mL i.v. infusion set. Blood samples were analyzed for plasma catecholamine levels. Respiration rate and oxygen saturation did not alter significantly from baseline levels. Heart rate and systolic blood pressure remained stable with an increase of 15% in heart rate and 6% in systolic blood pressure only at 10 minutes following the bolus loading. Diastolic blood pressure did not alter significantly from baseline levels (P < .05). Plasma catecholamines levels remained stable except for an increase in epinephrine (38%) and norepinephrine (19%) 10 minutes following the bolus injections. Plasma dopamine levels remained unchanged. There were no cases of unpleasant dreaming, dysphoria, or emergence-type reactions. This combined nonnarcotic sedoanalgesic technique maintains spontaneous ventilation and stable cardiorespiratory parameters and may be considered as an alternative to traditional conscious sedation or general anesthesia.

  17. Effects of a midazolam-ketamine admixture in human volunteers.

    PubMed Central

    Morse, Zac; Sano, Kimito; Kanri, Tomio

    2004-01-01

    As the ideal sedative does not exist for all situations, we examined the effect of a midazolam-ketamine sedoanalgesic admixture in human volunteers. Ten ASA physical status I volunteers were administered loading doses of 0.07 mg/kg of midazolam followed by 0.7 mg/kg of ketamine. The same amount of midazolam and ketamine was then infused constantly over 1 hour via a 60 drops (gtts)/mL i.v. infusion set. Blood samples were analyzed for plasma catecholamine levels. Respiration rate and oxygen saturation did not alter significantly from baseline levels. Heart rate and systolic blood pressure remained stable with an increase of 15% in heart rate and 6% in systolic blood pressure only at 10 minutes following the bolus loading. Diastolic blood pressure did not alter significantly from baseline levels (P < .05). Plasma catecholamines levels remained stable except for an increase in epinephrine (38%) and norepinephrine (19%) 10 minutes following the bolus injections. Plasma dopamine levels remained unchanged. There were no cases of unpleasant dreaming, dysphoria, or emergence-type reactions. This combined nonnarcotic sedoanalgesic technique maintains spontaneous ventilation and stable cardiorespiratory parameters and may be considered as an alternative to traditional conscious sedation or general anesthesia. PMID:15497296

  18. Chemical stability of admixtures combining ziconotide with baclofen during simulated intrathecal administration.

    PubMed

    Shields, David; Montenegro, Rick; Aclan, Jennifer

    2007-10-01

    Objective.  To determine the stability of admixtures combining ziconotide with commercially formulated or powdered baclofen during simulated intrathecal infusion under laboratory conditions at 37°. Materials and Methods.  Admixtures of ziconotide (25 µg/mL) with commercially formulated (1.5 mg/mL) or powdered (2.0 mg/mL) baclofen were stored in implantable intrathecal pumps at 37°. Drug concentrations were determined with high-performance liquid chromatography, and the length of time that the concentrations of both drugs remained ≥90% and ≥80% of initial (ie, the 90% and 80% stability, respectively) was estimated based on lower 95% confidence bounds obtained via linear regression. Results.  Baclofen was stable in both admixtures. In the commercially formulated baclofen admixture, the mean ziconotide concentration declined to 82.2% of initial in 30 days; the estimates for 90% and 80% stability were 12 and 29 days, respectively. In the powdered baclofen admixture, the mean ziconotide concentration declined to 87.4% of initial in 30 days; the estimates for 90% and 80% stability were 20 and 41 days, respectively. Conclusion.  Ziconotide-baclofen admixtures were more stable when prepared using powdered baclofen rather than a commercial baclofen formulation.

  19. Effect of mineral viscosity-enhancing admixtures on the solidification of evaporator concentrates.

    PubMed

    Lin, Chung-Yung; Huang, Wan-Ting

    2015-11-15

    It is known that partial replacement of cement by viscosity-enhancing admixtures, also known as anti-washout admixtures, affects the quality of the waste form or concrete. To reduce the bleeding rate of the paste, the characteristics of various mineral viscosity-enhancing admixtures dispersed in saline solutions were investigated, including sedimentation and viscosity. The admixture candidates included fly ash, silica fume, bentonite, and palygorskite. The effect of these admixtures blended with a cement-based matrix on the bleeding rate of the solidification of evaporator concentrates was also examined in this paper. The experimental results show the palygorskite Type 400 is the best choice to improve the quality of waste form, due to its excellent suspension property in the saline solution. The bleeding rate of paste decreased as the dispersion volume of the admixture suspension increased. For consideration of the quality of waste forms and the concentrate loading, the optimization of the palygorskite/concentrate ratio of 15-17 wt% and solidification agent/concentrate ratio of 1.0-1.2 were adopted. With this recipe, the quality of waste forms resulting from the solidification of simulated and actual evaporator concentrates mainly containing chloride met the regulations' requirements.

  20. Reconstructing Past Admixture Processes from Local Genomic Ancestry Using Wavelet Transformation.

    PubMed

    Sanderson, Jean; Sudoyo, Herawati; Karafet, Tatiana M; Hammer, Michael F; Cox, Murray P

    2015-06-01

    Admixture between long-separated populations is a defining feature of the genomes of many species. The mosaic block structure of admixed genomes can provide information about past contact events, including the time and extent of admixture. Here, we describe an improved wavelet-based technique that better characterizes ancestry block structure from observed genomic patterns. principal components analysis is first applied to genomic data to identify the primary population structure, followed by wavelet decomposition to develop a new characterization of local ancestry information along the chromosomes. For testing purposes, this method is applied to human genome-wide genotype data from Indonesia, as well as virtual genetic data generated using genome-scale sequential coalescent simulations under a wide range of admixture scenarios. Time of admixture is inferred using an approximate Bayesian computation framework, providing robust estimates of both admixture times and their associated levels of uncertainty. Crucially, we demonstrate that this revised wavelet approach, which we have released as the R package adwave, provides improved statistical power over existing wavelet-based techniques and can be used to address a broad range of admixture questions.

  1. Research Map of Research Priorities in HE Studies in the Kingdom of Saudi Arabia

    ERIC Educational Resources Information Center

    AlSumih, A. M.

    2016-01-01

    This study presents a research map for the key research priorities of higher education (HE) in the Kingdom of Saudi Arabia. The study diagnoses and analyzes the research reality in HE studies in KSA in terms of strength points and improvement opportunities. It also explores the research map fields of current and prospective research priorities in…

  2. Structural mapping: how to study the genetic architecture of a phenotypic trait through its formation mechanism.

    PubMed

    Tong, Chunfa; Shen, Lianying; Lv, Yafei; Wang, Zhong; Wang, Xiaoling; Feng, Sisi; Li, Xin; Sui, Yihan; Pang, Xiaoming; Wu, Rongling

    2014-01-01

    Traditional approaches for genetic mapping are to simply associate the genotypes of a quantitative trait locus (QTL) with the phenotypic variation of a complex trait. A more mechanistic strategy has emerged to dissect the trait phenotype into its structural components and map specific QTLs that control the mechanistic and structural formation of a complex trait. We describe and assess such a strategy, called structural mapping, by integrating the internal structural basis of trait formation into a QTL mapping framework. Electrical impedance spectroscopy (EIS) has been instrumental for describing the structural components of a phenotypic trait and their interactions. By building robust mathematical models on circuit EIS data and embedding these models within a mixture model-based likelihood for QTL mapping, structural mapping implements the EM algorithm to obtain maximum likelihood estimates of QTL genotype-specific EIS parameters. The uniqueness of structural mapping is to make it possible to test a number of hypotheses about the pattern of the genetic control of structural components. We validated structural mapping by analyzing an EIS data collected for QTL mapping of frost hardiness in a controlled cross of jujube trees. The statistical properties of parameter estimates were examined by simulation studies. Structural mapping can be a powerful alternative for genetic mapping of complex traits by taking account into the biological and physical mechanisms underlying their formation.

  3. Snow mapping and land use studies in Switzerland

    NASA Technical Reports Server (NTRS)

    Haefner, H. (Principal Investigator)

    1977-01-01

    The author has identified the following significant results. A system was developed for operational snow and land use mapping, based on a supervised classification method using various classification algorithms and representation of the results in maplike form on color film with a photomation system. Land use mapping, under European conditions, was achieved with a stepwise linear discriminant analysis by using additional ratio variables. On fall images, signatures of built-up areas were often not separable from wetlands. Two different methods were tested to correlate the size of settlements and the population with an accuracy for the densely populated Swiss Plateau between +2 or -12%.

  4. Inferring separate parental admixture components in unknown DNA samples using autosomal SNPs.

    PubMed

    Crouch, Daniel J M; Weale, Michael E

    2012-12-01

    The identification of ancestral admixture proportions for human DNA samples has recently had success in forensic cases. Current methods infer admixture proportions for the target sample, but not for their parents, which provides an additional layer of information that may aid certain forensic investigations. We describe new maximum likelihood methods (LEAPFrOG and LEAPFrOG Expectation Maximisation), for inferring both an individual's admixture proportions and the admixture proportions possessed by the unobserved parents, with respect to two or more source populations, using single-nucleotide polymorphism data typed only in the target individual. This is achieved by examining the increase in heterozygosity in the offspring of parents who are from different populations or who represent different mixtures from a number of source populations. We validated the methods via simulation; combining chromosomes from different Hapmap Phase III population samples to emulate first-generation admixture. Performance was strong for individuals with mixed African/European (YRI/CEU) ancestry, but poor for mixed Japanese/Chinese (JPT/CHB) ancestry, reflecting the difficulty in distinguishing closely related source populations. A total of 11 African-American trios were used to compare the parental admixture inferred from their own genotypes against that inferred purely from their offspring genotypes. We examined the performance of 34 ancestry informative markers from a multiplex kit for ancestry inference. Simulations showed that estimates were unreliable when parents had similar admixture, suggesting more markers are needed. Our results demonstrate that ancestral backgrounds of case samples and their parents are obtainable to aid in forensic investigations, provided that high-throughput methods are adopted by the forensic community.

  5. An Improved Approach for Mapping Quantitative Trait loci in a Pseudo-Testcross: Revisiting a Poplar Mapping Study

    SciTech Connect

    Wullschleger, Stan D; Wu, Song; Wu, Rongling; Yang, Jie; Li, Yao; Yin, Tongming; Tuskan, Gerald A

    2010-01-01

    A pseudo-testcross pedigree is widely used for mapping quantitative trait loci (QTL) in outcrossing species, but the model for analyzing pseudo-testcross data borrowed from the inbred backcross design can only detect those QTLs that are heterozygous only in one parent. In this study, an intercross model that incorporates the high heterozygosity and phase uncertainty of outcrossing species was used to reanalyze a published data set on QTL mapping in poplar trees. Several intercross QTLs that are heterozygous in both parents were detected, which are responsible not only for biomass traits, but also for their genetic correlations. This study provides a more complete identification of QTLs responsible for economically important biomass traits in poplars.

  6. An Improved Approach for Mapping Quantitative Trait Loci in a Pseudo-Testcross: Revisiting a Poplar Mapping Study

    SciTech Connect

    Tuskan, Gerald A; Yin, Tongming; Wullschleger, Stan D; Yang, Jie; Huang, Youjun; Li, Yao; Wu, Rongling

    2010-01-01

    A pseudo-testcross pedigree is widely used for mapping quantitative trait loci (QTL) in outcrossing species, but the model for analyzing pseudo-testcross data borrowed from the inbred backcross design can only detect those QTLs that are heterozygous only in one parent. In this study, an intercross model that incorporates the high heterozygosity and phase uncertainty of outcrossing species was used to reanalyze a published data set on QTL mapping in poplar trees. Several intercross QTLs that are heterozygous in both parents were detected, which are responsible not only for biomass traits, but also for their genetic correlations. This study provides a more complete identification of QTLs responsible for economically important biomass traits in poplars.

  7. An improved approach for mapping quantitative trait Loci in a pseudo-testcross: revisiting a poplar mapping study.

    PubMed

    Wu, Song; Yang, Jie; Huang, Youjun; Li, Yao; Yin, Tongming; Wullschleger, Stan D; Tuskan, Gerald A; Wu, Rongling

    2010-02-04

    A pseudo-testcross pedigree is widely used for mapping quantitative trait loci (QTL) in outcrossing species, but the model for analyzing pseudo-testcross data borrowed from the inbred backcross design can only detect those QTLs that are heterozygous only in one parent. In this study, an intercross model that incorporates the high heterozygosity and phase uncertainty of outcrossing species was used to reanalyze a published data set on QTL mapping in poplar trees. Several intercross QTLs that are heterozygous in both parents were detected, which are responsible not only for biomass traits, but also for their genetic correlations. This study provides a more complete identification of QTLs responsible for economically important biomass traits in poplars.

  8. Porcine NAMPT gene: search for polymorphism, mapping and association studies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    NAMPT encodes for an enzyme catalysing the rate-limiting step in NAD biosynthesis. The extracellular form of the enzyme is known as adipokine visfatin. We detected SNP AM999341:g.669T>C in intron 9 and SNP FN392209:g.358A>G in the promoter of the gene. RH mapping linked the gene to microsatellite SW...

  9. Chesapeake Bay Low Freshwater Inflow Study. Appendix F. Map Folio.

    DTIC Science & Technology

    1984-09-01

    storage, conservation, growth restriction, oyster bed restoration , and fisheries management. The final report recommends that a comprehensive water...AHANNROCK RIVER YORK ~ \\ RIVERJ JAMS RVE ~7. MAP 3 CHESAPEAKE BAY Prorocefltrum minimum , OIFLAGELLATIE -"S -, ASE AVERAGE WESTERN ECO SYSTEMS TECNOLOGY

  10. Age-Related Weakness of Proximal Muscle Studied with Motor Cortical Mapping: A TMS Study

    PubMed Central

    Plow, Ela B.; Varnerin, Nicole; Cunningham, David A.; Janini, Daniel; Bonnett, Corin; Wyant, Alexandria; Hou, Juliet; Siemionow, Vlodek; Wang, Xiao-Feng; Machado, Andre G.; Yue, Guang H.

    2014-01-01

    Aging-related weakness is due in part to degeneration within the central nervous system. However, it is unknown how changes to the representation of corticospinal output in the primary motor cortex (M1) relate to such weakness. Transcranial magnetic stimulation (TMS) is a noninvasive method of cortical stimulation that can map representation of corticospinal output devoted to a muscle. Using TMS, we examined age-related alterations in maps devoted to biceps brachii muscle to determine whether they predicted its age-induced weakness. Forty-seven right-handed subjects participated: 20 young (22.6±0.90 years) and 27 old (74.96±1.35 years). We measured strength as force of elbow flexion and electromyographic activation of biceps brachii during maximum voluntary contraction. Mapping variables included: 1) center of gravity or weighted mean location of corticospinal output, 2) size of map, 3) volume or excitation of corticospinal output, and 4) response density or corticospinal excitation per unit area. Center of gravity was more anterior in old than in young (p<0.001), though there was no significant difference in strength between the age groups. Map size, volume, and response density showed no significant difference between groups. Regardless of age, center of gravity significantly predicted strength (β = −0.34, p = 0.005), while volume adjacent to the core of map predicted voluntary activation of biceps (β = 0.32, p = 0.008). Overall, the anterior shift of the map in older adults may reflect an adaptive change that allowed for the maintenance of strength. Laterally located center of gravity and higher excitation in the region adjacent to the core in weaker individuals could reflect compensatory recruitment of synergistic muscles. Thus, our study substantiates the role of M1 in adapting to aging-related weakness and subtending strength and muscle activation across age groups. Mapping from M1 may offer foundation for an examination of mechanisms

  11. Using Digital Mapping Programs to Augment Student Learning in Social Studies

    ERIC Educational Resources Information Center

    Chandler, Thomas; An, Heejung

    2007-01-01

    Thomas Chandler and Heejung An describe how digital mapping technology can be incorporated into community-based K-12 social studies projects. According to Chandler and An, digital mapping can add value to the social studies curriculum by enabling students to better understand the interdependence between the lives of individuals and their…

  12. Investigation of metastable production in a closed-cell dielectric capillary variable pressure He plasma jet with Ar admixture

    NASA Astrophysics Data System (ADS)

    Sands, Brian; Ganguly, Biswa

    2011-10-01

    For plasma processing applications of streamer-like atmospheric pressure plasma jets generated in a dielectric capillary, we have demonstrated that an admixture of Ar to the He gas flow greatly increases the lifetime of energetic species in the core flow through enhanced afterglow production of Ar 1s5 metastable species. To study this effect in more detail, we have used a closed-cell plasma jet that allows control over the background gas pressure and composition. We used a 20 ns risetime positive unipolar voltage pulse for excitation. A He flow with a 0-30% Ar admixture was studied using time-resolved emission and tunable diode laser absorption spectroscopy of the Ar 1s5 and He 23S metastable states. Nitrogen was used as the background gas. In pure He and pure Ar gases the He and Ar metastables respectively are produced in the first ~100 ns only in the active discharge. With Ar added to the He gas flow, He metastables produced in the active discharge are quickly quenched via Penning ionization of Ar while Ar 1s5 is enhanced over 1-2 μs in the afterglow, increasing the number density as high as 1013/cc and extending the effective lifetime up to 10 μs. This implies that He heavy particle kinetics are a key driver of enhanced afterglow plasma chemistry in plasma jets with rare gas mixtures.

  13. Comparison of propofol (1%) with admixture (1:1) of thiopentone (1.25%) and propofol (0.5%) for laryngeal mask airway insertion in children undergoing elective eye surgery: Double-masked randomized clinical trial

    PubMed Central

    Sinha, Renu; Shende, Dilip; Garg, Rakesh

    2010-01-01

    Intravenous propofol 1% has been the preferred agent for Laryngeal Mask Airway (LMA) insertion. Admixture of thiopentone 1.25% and propofol 0.5% (1:1) has been used by various authors for induction as well as insertion of LMA in adults. There is no previous report where this admixture has been used for insertion of LMA in children. This study has been designed to investigate whether this admixture can be a suitable alternative to propofol, in relation to ease of insertion of the LMA, haemodynamic stability, cost containment, pain on injection and recovery in children. In this randomized, double-masked study, 50 ASA grade 1 and 2 patients of age 3 – 15 years and weighing more than 10 kg were included. The patients were divided into two groups; the P group received propofol 1%, while the Ad group received an admixture of thiopentone 1.25% and propofol 0.5% (1:1). All the children were evaluated for incidence of apnoea, pain on injection, jaw relaxation, ease of LMA insertion, coughing, gagging, laryngospasm, involuntary limb movements, incidence of hypotension and recovery. The demographic data, incidence of apnoea, pain on injection, jaw relaxation, ease of LMA insertion, coughing, gagging and involuntary movements were comparable in both groups. In the P group recovery was faster as compared to the Ad group. The admixture was cost effective as compared to Propofol alone [Indian National Rupees (INR) 24.64 ± 7.62 vs. INR 48.75 ± 23.25] (P = 0.001)). Admixture of propofol and thiopentone was a cheap, safe and effective alternative to propofol alone, for LMA insertion in children. PMID:20661346

  14. Lack of gene-language correlation due to reciprocal female but directional male admixture in Austronesians and non-Austronesians of East Timor.

    PubMed

    Gomes, Sibylle M; van Oven, Mannis; Souto, Luis; Morreira, Helena; Brauer, Silke; Bodner, Martin; Zimmermann, Bettina; Huber, Gabriela; Strobl, Christina; Röck, Alexander W; Côrte-Real, Francisco; Parson, Walther; Kayser, Manfred

    2017-02-01

    Nusa Tenggara, including East Timor, located at the crossroad between Island Southeast Asia, Near Oceania, and Australia, are characterized by a complex cultural structure harbouring speakers from two different major linguistic groups of different geographic origins (Austronesian (AN) and non-Austronesian (NAN)). This provides suitable possibilities to study gene-language relationship; however, previous studies from other parts of Nusa Tenggara reported conflicting evidence about gene-language correlation in this region. Aiming to investigate gene-language relationships including sex-mediated aspects in East Timor, we analysed the paternally inherited non-recombining part of the Y chromosome (NRY) and the maternally inherited mitochondrial (mt) DNA in a representative collection of AN- and NAN-speaking groups. Y-SNP (single-nucleotide polymorphism) data were newly generated for 273 samples and combined with previously established Y-STR (short tandem repeat) data of the same samples, and with previously established mtDNA data of 290 different samples with, however, very similar representation of geographic and linguistic coverage of the country. We found NRY and mtDNA haplogroups of previously described putative East/Southeast Asian (E/SEA) and Near Oceanian (NO) origins in both AN and NAN speakers of East Timor, albeit in different proportions, suggesting reciprocal genetic admixture between both linguistic groups for females, but directional admixture for males. Our data underline the dual genetic origin of East Timorese in E/SEA and NO, and highlight that substantial genetic admixture between the two major linguistic groups had occurred, more so via women than men. Our study therefore provides another example where languages and genes do not conform due to sex-biased genetic admixture across major linguistic groups.

  15. The Effect of Solid Admixtures on the Velocity of Motion of a Free Dusty Air Jet

    NASA Technical Reports Server (NTRS)

    Chernov, A. P.

    1957-01-01

    In dusty air flows occurring in industrial practice in transport by air pressure of friable materials, in the drying, annealing, and so forth, of a pulverized solid mass in suspension, and in other processes, the concentration of solid particles usually has a magnitude of the order of 1 kg per 1 kg of air. At such a concentration, the ratio of the volume of the particles to the volume of the air is small (less than one-thousandth part). However, regardless of this, the presence of a solid admixture manifests itself in the rules for the velocity distribution of the air in a dusty air flow. As a result, the rules of velocity change are different for clean and for dusty air flows. The estimation of the influence of the admixture on the velocity of the motion of the flow presents a definitive interest. One of the attempts to estimate that influence on the axial velocity of a free axially symmetrical jet with admixtures was made by Abramovich. Abramovich assumed beforehand that the fine particles of the admixture in the jet are subject to the motion of the air (that is, that the velocity of the admixture is approximately equal to the local velocity of the air); he then took as the basis of his considerations, in solving the problem, the condition that the amount of motion of the two-phase jet must be constant.

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

    PubMed Central

    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

  17. Winning the invasion roulette: escapes from fish farms increase admixture and facilitate establishment of non-native rainbow trout

    PubMed Central

    Consuegra, Sofia; Phillips, Nia; Gajardo, Gonzalo; de Leaniz, Carlos Garcia

    2011-01-01

    Aquaculture is a major source of invasive aquatic species, despite the fact that cultured organisms often have low genetic diversity and tend to be maladapted to survive in the wild. Yet, to what extent aquaculture escapees become established by means of high propagule pressure and multiple origins is not clear. We analysed the genetic diversity of 15 established populations and four farmed stocks of non-native rainbow trout in Chile, a species first introduced for recreational fishing around 1900, but which has in recent decades escaped in large numbers from fish farms and become widespread. Aquaculture propagule pressure was a good predictor of the incidence of farm escapees, which represented 16% of all free-ranging rainbow trout and were present in 80% of the study rivers. Hybrids between farm escapes and established trout were present in all rivers at frequencies ranging between 7 and 69%, and population admixture was positively correlated with genetic diversity. We suggest that non-native salmonids introduced into the Southern Hemisphere could benefit from admixture because local adaptations may not have yet developed, and there may be initially little fitness loss resulting from outbreeding depression. PMID:25568013

  18. Range expansion of house sparrows (Passer domesticus) in Kenya: evidence of genetic admixture and human-mediated dispersal.

    PubMed

    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.

  19. Admixture in Latin America: Geographic Structure, Phenotypic Diversity and Self-Perception of Ancestry Based on 7,342 Individuals

    PubMed Central

    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

  20. Pedagogical Knowledge Representation through Concept Mapping as a Study and Collaboration Tool in Teacher Education

    ERIC Educational Resources Information Center

    Koc, Mustafa

    2012-01-01

    This study explored (a) pre-service teachers' perceptions of using concept mapping (CM) in one of their pedagogical courses, (b) the predictive power of such implementation in course achievement, and (c) the role of prior experience with CM, type of mapping, and gender on their perceptions and performances in CM and achievement. The subjects were…

  1. Mapping Civic Engagement: A Case Study of Service-Learning in Appalachia

    ERIC Educational Resources Information Center

    Mann, Jessica; Casebeer, Daniel

    2016-01-01

    This study uses social cartography to map student perceptions of a co-curricular service-learning project in an impoverished rural community. As a complement to narrative discourse, mapping provides an opportunity to visualize not only the spatial nature of the educational experience but also, in this case, the benefits of civic engagement. The…

  2. Preservice Teachers Map Compassion: Connecting Social Studies and Literacy through Nonfictional Animal Stories

    ERIC Educational Resources Information Center

    Rule, Audrey C.; Montgomery, Sarah E.; Vander Zanden, Sarah M.

    2014-01-01

    Nonfiction stories of animal compassion were used in this literacy-social studies integrated lesson to address both efferent and aesthetic stances in transmediation of text from picture books to maps. Preservice early childhood and elementary teachers chose places from the nine recent children's stories, symbolizing them on a map while…

  3. An Exploratory Study of Elementary Preservice Teachers' Understanding of Ecology Using Concept Maps

    ERIC Educational Resources Information Center

    Zak, Kevin M.; Munson, Bruce H.

    2008-01-01

    Classroom teachers serve a critical role in developing environmentally literate citizens. In this study, the authors assessed K-8 preservice teachers' understanding of basic ecological concepts. Participants (N = 56) constructed concept maps describing the inter-relationships among 16 ecological concepts. The authors analyzed the concept maps to…

  4. An Adult Education Study of Participatory Community Mapping for Indigenous Knowledge Production

    ERIC Educational Resources Information Center

    Campbell, Craig A., Jr.

    2010-01-01

    This dissertation explores the notion of participatory community mapping (PCM) for Indigenous knowledge production. Three major questions were posed in the study. First, how can PCM foster Indigenous knowledge production and documentation? Second, how can PCM be used to include local voice and input in mapping projects, and third, how can adult…

  5. iMindMap as an Innovative Tool in Teaching and Learning Accounting: An Exploratory Study

    ERIC Educational Resources Information Center

    Wan Jusoh, Wan Noor Hazlina; Ahmad, Suraya

    2016-01-01

    Purpose: The purpose of this study is to explore the use of iMindMap software as an interactive tool in the teaching and learning method and also to be able to consider iMindMap as an alternative instrument in achieving the ultimate learning outcome. Design/Methodology/Approach: Out of 268 students of the management accounting at the University of…

  6. Using Concept Maps to Elicit and Study Student Teachers' Perceptions about Inclusive Education: A Tanzanian Experience

    ERIC Educational Resources Information Center

    Wormnaes, Siri; Mkumbo, Kitila; Skaar, Bjørn; Refseth, Yngve

    2015-01-01

    In this study, concept map activities were used to trigger group discussions about inclusive education, with a focus on learners with disabilities. The participants were 226 Tanzanian student teachers. This article reports and discusses how the maps were analysed and what they indicate about the students' thinking about certain aspects of…

  7. Investigating Word Learning in Fragile X Syndrome: A Fast-Mapping Study

    ERIC Educational Resources Information Center

    McDuffie, Andrea; Kover, Sara T.; Hagerman, Randi; Abbeduto, Leonard

    2013-01-01

    Fast-mapping paradigms have not been used previously to examine the process of word learning in boys with fragile X syndrome (FXS), who are likely to have intellectual impairment, language delays, and symptoms of autism. In this study, a fast-mapping task was used to investigate associative word learning in 4- to 10-year-old boys with FXS relative…

  8. Use of admixtures in organic-contaminated cement-clay pastes.

    PubMed

    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.

  9. PREMIX: PRivacy-preserving EstiMation of Individual admiXture

    PubMed Central

    Chen, Feng; Dow, Michelle; Ding, Sijie; Lu, Yao; Jiang, Xiaoqian; Tang, Hua; Wang, Shuang

    2016-01-01

    In this paper we proposed a framework: PRivacy-preserving EstiMation of Individual admiXture (PREMIX) using Intel software guard extensions (SGX). SGX is a suite of software and hardware architectures to enable efficient and secure computation over confidential data. PREMIX enables multiple sites to securely collaborate on estimating individual admixture within a secure enclave inside Intel SGX. We implemented a feature selection module to identify most discriminative Single Nucleotide Polymorphism (SNP) based on informativeness and an Expectation Maximization (EM)-based Maximum Likelihood estimator to identify the individual admixture. Experimental results based on both simulation and 1000 genome data demonstrated the efficiency and accuracy of the proposed framework. PREMIX ensures a high level of security as all operations on sensitive genomic data are conducted within a secure enclave using SGX. PMID:28269933

  10. PREMIX: PRivacy-preserving EstiMation of Individual admiXture.

    PubMed

    Chen, Feng; Dow, Michelle; Ding, Sijie; Lu, Yao; Jiang, Xiaoqian; Tang, Hua; Wang, Shuang

    2016-01-01

    In this paper we proposed a framework: PRivacy-preserving EstiMation of Individual admiXture (PREMIX) using Intel software guard extensions (SGX). SGX is a suite of software and hardware architectures to enable efficient and secure computation over confidential data. PREMIX enables multiple sites to securely collaborate on estimating individual admixture within a secure enclave inside Intel SGX. We implemented a feature selection module to identify most discriminative Single Nucleotide Polymorphism (SNP) based on informativeness and an Expectation Maximization (EM)-based Maximum Likelihood estimator to identify the individual admixture. Experimental results based on both simulation and 1000 genome data demonstrated the efficiency and accuracy of the proposed framework. PREMIX ensures a high level of security as all operations on sensitive genomic data are conducted within a secure enclave using SGX.

  11. Genome-wide ancestry and divergence patterns from low-coverage sequencing data reveal a complex history of admixture in wild baboons

    PubMed Central

    Wall, Jeffrey D; Schlebusch, Stephen A; Alberts, Susan C; Cox, Laura A; Snyder-Mackler, Noah; Nevonen, Kimberly; Carbone, Lucia; Tung, Jenny

    2017-01-01

    Naturally occurring admixture has now been documented in every major primate lineage, suggesting its key role in primate evolutionary history. Active primate hybrid zones can provide valuable insight into this process. Here, we investigate the history of admixture in one of the best-studied natural primate hybrid zones, between yellow baboons (Papio cynocephalus) and anubis baboons (Papio anubis) in the Amboseli ecosystem of Kenya. We generated a new genome assembly for yellow baboon and low coverage genome-wide resequencing data from yellow baboons, anubis baboons, and known hybrids (n=44). Using a novel composite likelihood method for estimating local ancestry from low coverage data, we found high levels of genetic diversity and genetic differentiation between the parent taxa, and excellent agreement between genome-scale ancestry estimates and a priori pedigree, life history, and morphology-based estimates (r2=0.899). However, even putatively unadmixed Amboseli yellow individuals carried a substantial proportion of anubis ancestry, presumably due to historical admixture. Further, the distribution of shared versus fixed differences between a putatively unadmixed Amboseli yellow baboon and an unadmixed anubis baboon, both sequenced at high coverage, are inconsistent with simple isolation-migration or equilibrium migration models. Our findings suggest a complex process of intermittent contact that has occurred multiple times in baboon evolutionary history, despite no obvious fitness costs to hybrids or major geographic or behavioral barriers. In combination with the extensive phenotypic data available for baboon hybrids, our results provide valuable context for understanding the history of admixture in primates, including in our own lineage. PMID:27145036

  12. Velocity map ion imaging study of Ar2+ photodissociation

    NASA Astrophysics Data System (ADS)

    Maner, J. A.; Mauney, D. T.; Duncan, M. A.

    2017-03-01

    The argon dimer cation is produced in a plasma generated by a laser spark in a supersonic expansion. The cold ions are mass selected and investigated by photodissociation at 355 nm, with velocity map imaging of the Ar+ photofragment. Using the radius of the image, we determine the kinetic energy release and derive the ground state dissociation energy of Ar2+ as D0″ = 1.32 +0.03/-0.02 eV. Additionally, the angular distribution is described with β = 1.71-1.95, consistent with excitation of the parallel-type 2Σg+ ← 2Σu+ transition.

  13. Symbolic, Nonsymbolic and Conceptual: An Across-Notation Study on the Space Mapping of Numerals.

    PubMed

    Zhang, Yu; You, Xuqun; Zhu, Rongjuan

    2016-07-01

    Previous studies suggested that there are interconnections between two numeral modalities of symbolic notation and nonsymbolic notation (array of dots), differences and similarities of the processing, and representation of the two modalities have both been found in previous research. However, whether there are differences between the spatial representation and numeral-space mapping of the two numeral modalities of symbolic notation and nonsymbolic notation is still uninvestigated. The present study aims to examine whether there are differences between the spatial representation and numeral-space mapping of the two numeral modalities of symbolic notation and nonsymbolic notation; especially how zero, as both a symbolic magnitude numeral and a nonsymbolic conceptual numeral, mapping onto space; and if the mapping happens automatically at an early stage of the numeral information processing. Results of the two experiments demonstrate that the low-level processing of symbolic numerals including zero and nonsymbolic numerals except zero can mapping onto space, whereas the low-level processing of nonsymbolic zero as a semantic conceptual numeral cannot mapping onto space, which indicating the specialty of zero in the numeral domain. The present study indicates that the processing of non-semantic numerals can mapping onto space, whereas semantic conceptual numerals cannot mapping onto space.

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

    PubMed

    Pool, John E; Corbett-Detig, Russell B; Sugino, Ryuichi P; Stevens, Kristian A; Cardeno, Charis M; Crepeau, Marc W; Duchen, Pablo; Emerson, J J; Saelao, Perot; Begun, David J; Langley, Charles H

    2012-01-01

    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 elevated

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Mapping geomorphological diversity. A case study in Derborence (Valais, Swiss Alps)

    NASA Astrophysics Data System (ADS)

    Maret, Hélène; Reynard, Emmanuel

    2015-04-01

    "Geodiversity is the natural range (diversity) of geological (rocks, minerals, fossils), geomorphological (landforms, processes) and soils features. It includes their assemblages, relationships, properties, interpretations and systems." (Gray, 2004: 6). Geodiversity has a strong spatial component and cartography is one good tool to characterize it. In this work, we focus on the geomorphological diversity defined as one part of geodiversity. The aim of this study is to assess geomorphological diversity based on a geomorphological map. A method was then developed to transform the latter into a map of geomorphological diversity. In other words, we transformed a qualitative geomorphological map (morphogenetic map) into a quantitative map (including the value of a geomorphological diversity index). The University of Lausanne has recently developed a geomorphological mapping legend on ArcGIS (Lambiel et al., in press). This system classifies the landforms according to various morphogenetical contexts (glacial, periglacial, fluvial, karstic, etc.). Each form is represented as a surface (e.g. alluvial fan), a line (e.g. moraine) or a dot (e.g. spring, sinkhole). As the geomorphological mapping legend was basically developed for graphical purposes, a first step was to transform the geomorphological map into a map only filled with polygons in order to delimitate precisely areas occupied by points and lines elements (for example rivers or holes). After that, a grid was added to compute the geomorphological diversity by counting the number of elements per square. It results in a raster map with a geomorphological diversity index split into five categories (very high, high, medium, low, very low). We also tested which square size was the most accurate for our purpose and checked whether this index produced interesting results. This attempt to define and test a new methodology for assessing geomorphological diversity could afterward be used to transform other maps (geology

  17. Admixture between native and invasive populations may increase invasiveness of Mimulus guttatus.

    PubMed

    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.

  18. Effect of negative gases admixture on the stability of beam-driven discharges

    NASA Astrophysics Data System (ADS)

    Levko, Dmitry; Raja, Laxminarayan L.

    2016-12-01

    The influence of negative gas SF6 admixture on the stability of low-pressure beam-driven discharge is studied by self-consistent 1D particle-in-cell/Monte Carlo collisions model. We find that the plasma parameters as well as its stability are changed drastically when SF6 is added to argon gas. In an electropositive plasma we obtain the excitation of both fast and slow electrostatic plasma waves which is explained by the propagation of electron beam through the non-homogeneous bounded plasma. These waves lead to the heating of plasma electrons and ions. On the other hand, in electronegative plasma we also obtain a decay of the electron beam. However, since in electronegative beam-generated plasma the electron plasma density is homogeneous the beam is more stable. As a consequence, we obtain only the excitation of two fast electrostatic waves. One wave is excited due to two-stream instability and another wave is excited due to beam decay. The excitation of these fast waves does not influence the plasma homogeneity but influences the heating of plasma electrons.

  19. Performance of rice husk ash produced using a new technology as a mineral admixture in concrete

    SciTech Connect

    Nehdi, M.; Duquette, J.; El Damatty, A

    2003-08-01

    This article investigates the use of a new technique for the controlled combustion of Egyptian rice husk to mitigate the environmental concerns associated with its uncontrolled burning and provide a supplementary cementing material for the local construction industry. The reactor used provides efficient combustion of rice husk in a short residency time via the suspension of processed particles by jets of a process air stream that is forced though stationary angled blades at high velocity. Investigations on the rice husk ash (RHA) thus produced included oxide analysis, X-ray diffraction, carbon content, grindability, water demand, pozzolanic activity index, surface area, and particle size distribution measurements. In addition, concrete mixtures incorporating various proportions of silica fume (SF) and Egyptian RHA (EG-RHA) produced at different combustion temperatures were made and compared. The workability, superplasticizer and air-entraining admixture requirements, and compressive strength at various ages of these concrete mixtures were evaluated, and their resistance to rapid chloride penetrability and deicing salt surface scaling were examined. Test results indicate that contrary to RHA produced using existing technology, the superplasticizer and air-entraining agent requirements did not increase drastically when the RHA developed in this study was used. Compressive strengths achieved by concrete mixtures incorporating the new RHA exceeded those of concretes containing similar proportions of SF. The resistance to surface scaling of RHA concrete was better than that of concrete containing similar proportions of SF. While the chloride penetrability was substantially decreased by RHA, it remained slightly higher than that achieved by SF concrete.

  20. Analysis of genetic admixture in Uyghur using the 26 Y-STR loci system.

    PubMed

    Bian, Yingnan; Zhang, Suhua; Zhou, Wei; Zhao, Qi; Siqintuya; Zhu, Ruxin; Wang, Zheng; Gao, Yuzhen; Hong, Jie; Lu, Daru; Li, Chengtao

    2016-02-04

    The Uyghur population has experienced extensive interaction with European and Eastern Asian populations historically. A set of high-resolution genetic markers could be useful to infer the genetic relationships between the Uyghur population and European and Asian populations. In this study we typed 100 unrelated Uyghur males living in southern Xinjiang at 26 Y-STR loci. Using the high-resolution 26 Y-STR loci system, we investigated genetic and phylogenetic relationship between the Uyghur population and 23 reference European or Asian populations. We found that the Uyghur population exhibited a genetic admixture of Eastern Asian and European populations, and had a slightly closer relationship with the selected European populations than the Eastern Asian populations. We also demonstrated that the 26 Y-STR loci system was potentially useful in forensic sciences because it has a large power of discrimination and rarely exhibits common haplotypes. However, ancestry inference of Uyghur samples could be challenging due to the admixed nature of the population.

  1. Racial and ethnic differences in assisted reproduction treatment outcomes: the benefit of racial admixture.

    PubMed

    Braga, Daniela Paes Almeida Ferreira; Setti, Amanda S; Iaconelli, Assumpto; Taitson, Paulo Franco; Borges, Edson

    2015-01-01

    The goal of the present study was to determine whether racial and ethnic differences affect the outcomes of assisted reproductive technology in the Brazilian population. 1497 patients undergoing intracytoplasmic sperm injection (ICSI) cycles were split into groups according to the patient's ethnicity: Caucasian (n = 2131), Mestizo (n = 358), Asian (n = 174), Black (n = 115) and Indian (n = 260). ICSI outcomes were compared among the groups. Body mass index was highest in the Black group, followed by the Mestizo, Indian, Caucasian and Asian groups (p > 0.001). The FSH dose (p > 0.001) was highest among Indians, followed by Asians and Caucasians, and the dose was lowest among Blacks and Mestizos. In contrast, the oocyte yield was highest among Mestizos, followed by Indians, Blacks and Caucasians, and lowest among Asians (p = 0.005). The fertilisation rate was highest among Mestizos, followed by Blacks, Indians and Caucasians, whereas Asians had the lowest fertilisation rate (p = 0.004). Pregnancy and implantation rates were also highest among Mestizos, followed by Blacks, Indians and Caucasians, whereas the Asian patients had the lowest rates (p = 0.008 and p > 0.001, respectively). In conclusion, our evidence suggests a possible beneficial effect of racial admixture on ICSI outcomes.

  2. Utilization of water-reducing admixtures in cemented paste backfill of sulphide-rich mill tailings.

    PubMed

    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.

  3. Sterility testing of a total nutrient admixture with a biphasic blood-culture system.

    PubMed

    Murray, P R; Sandrock, M J

    1991-11-01

    The ability of a biphasic blood-culture system to detect microbial contamination of a total nutrient admixture (TNA) was studied. A TNA consisting of amino acids, dextrose, lipid emulsion, electrolytes, and trace elements was prepared under aseptic conditions. Septi-Chek blood-culture bottles were then injected with a TNA sample and with one of various dilutions of five bacterial or fungal suspensions, and an agar slide unit was attached to each bottle. One bottle was injected only with a TNA sample. The bottles were incubated and examined once daily. Each bottle was inverted immediately after inoculation and at each observation time to allow the broth to wash over the agar slide unit. Because the lipid contained in the TNA caused the broth in all bottles to become turbid, it was impossible to determine whether microbial growth was present in the broth. Microbial growth, however, became evident in 24-72 hours on all slide units except the one attached to the bottle that had been injected only with TNA. The Septi-Chek biphasic blood-culture system appears to be useful in evaluating the sterility of TNAs.

  4. Analysis of genetic admixture in Uyghur using the 26 Y-STR loci system

    PubMed Central

    Bian, Yingnan; Zhang, Suhua; Zhou, Wei; Zhao, Qi; Siqintuya; Zhu, Ruxin; Wang, Zheng; Gao, Yuzhen; Hong, Jie; Lu, Daru; Li, Chengtao

    2016-01-01

    The Uyghur population has experienced extensive interaction with European and Eastern Asian populations historically. A set of high-resolution genetic markers could be useful to infer the genetic relationships between the Uyghur population and European and Asian populations. In this study we typed 100 unrelated Uyghur males living in southern Xinjiang at 26 Y-STR loci. Using the high-resolution 26 Y-STR loci system, we investigated genetic and phylogenetic relationship between the Uyghur population and 23 reference European or Asian populations. We found that the Uyghur population exhibited a genetic admixture of Eastern Asian and European populations, and had a slightly closer relationship with the selected European populations than the Eastern Asian populations. We also demonstrated that the 26 Y-STR loci system was potentially useful in forensic sciences because it has a large power of discrimination and rarely exhibits common haplotypes. However, ancestry inference of Uyghur samples could be challenging due to the admixed nature of the population. PMID:26842947

  5. Effects of drying conditions, admixtures and specimen size on shrinkage strains

    SciTech Connect

    Al-Saleh, Saleh A. . E-mail: alsaleh@dr.com; Al-Zaid, Rajeh Z.

    2006-10-15

    The paper presents the results of an experimental investigation on the effects of drying conditions, specimen size and presence of plasticizing admixture on the development of shrinkage strains. The measurements are taken in a harsh (50 deg. C and 5% R.H.) and a moderate environment (28 deg. C and 50% R.H.). The results include strain development at various levels of cross sections of concrete prisms. The drying conditions are found to be the dominant parameter affecting the shrinkage strain development particularly in specimens of smaller sizes. The effect of plasticizing admixture on shrinkage strains is negligible.

  6. International association for the study of lung cancer map, Wang lymph node map and rapid on-site evaluation in transbronchial needle aspiration

    PubMed Central

    Liu, Qing-Hua; Arias, Sixto

    2016-01-01

    The invaluable role of transbronchial needle aspiration (TBNA) in the diagnosis and staging of mediastinal adenopathy and lung cancer has been well established. Different lymph nodes regional nomenclatures and maps had been described over the years. The international association for the study of lung cancer (IASLC) and Wang’s maps complement each other benefiting patients with lung cancer. In this article we briefly reviewed the roles of IALSC, Wang’s maps and ROSE in TBNA. PMID:27747023

  7. The "frontal syndrome" revisited: lessons from electrostimulation mapping studies.

    PubMed

    Duffau, Hugues

    2012-01-01

    For a long time, in a localizationist view of brain functioning, a combination of symptoms called "frontal syndrome" has been interpreted as the direct result of damages involving the frontal lobe(s). The goal of this review is to challenge this view, that is, to move to a hodotopical approach to lesion mapping, on the basis of new insights provided by intraoperative electrostimulation mapping investigations in patients who underwent awake surgery for cerebral tumors. These original data reported in the last decade break with the traditional dogma of a modular and fixed organization of the central nervous system, by switching to the concepts of cerebral connectivity and plasticity - i.e., a brain organization based on dynamic interrelationships between parallel distributed networks. According to this revisited model, "frontal symptoms" can be generated by tumor or electrostimulation not only of the frontal lobes, but also of cortical and subcortical (white matter pathways/deep gray nuclei) structures outside the frontal lobes: especially, stimulation of the superior longitudinal fascicle may elicit speech production disorders, syntactic disturbances, involuntary language switching or phonemic paraphasia (arcuate fascicle), stimulation of the inferior fronto-occipital fascicle can generate semantic paraphasia or deficit of cross-modal judgment, stimulation of the subcallosal fasciculus may elicit transcortical motor aphasia, while stimulation of the striatum induces preservations. On the other hand, it is also possible to perform extensive right or left frontal lobectomy in patients who continue to have a normal familial, social and professional life, without "frontal syndrome". Therefore, this provocative approach may open the door to a renewal in the modeling of brain processing as well as in its clinical applications, especially in the fields of cerebral surgery and functional rehabilitation. These findings illustrate well the need to reinforce links between

  8. Pilot study of the application of Tellus airborne radiometric and soil geochemical data for radon mapping.

    PubMed

    Appleton, J D; Miles, J C H; Green, B M R; Larmour, R

    2008-10-01

    The scope for using Tellus Project airborne gamma-ray spectrometer and soil geochemical data to predict the probability of houses in Northern Ireland having high indoor radon concentrations is evaluated, in a pilot study in the southeast of the province, by comparing these data statistically with in-house radon measurements. There is generally good agreement between radon maps modelled from the airborne radiometric and soil geochemical data using multivariate linear regression analysis and conventional radon maps which depend solely on geological and indoor radon data. The radon maps based on the Tellus Project data identify some additional areas where the radon risk appears to be relatively high compared with the conventional radon maps. One of the ways of validating radon maps modelled on the Tellus Project data will be to carry out additional indoor measurements in these areas.

  9. A STUDY ON REASONS OF ERRORS OF OLD SURVEY MAPS IN CADASTRAL SYSTEM

    NASA Astrophysics Data System (ADS)

    Yanase, Norihiko

    This paper explicates sources on survey map errors which were made in 19th century. The present cadastral system stands on registers and survey maps which were compiled to change the land taxation system in the Meiji era. Many Japanese may recognize the reasons why poor survey technique by farmers, too long measure to avoid heavy tax, careless official check and other deception made such errors of acreage from several to more than ten percent of area in survey maps. The author would like to maintain that such errors, called nawa-nobi, were lawful in accordance with the then survey regulation because of results to analyze old survey regulations, history of making maps and studies of cadastral system. In addition to, a kind of survey maps' errors should be pointed out a reason why the easy subdivision system which could approve without real survey and disposal of state property with inadequate survey.

  10. Methodology for mapping shallow groundwater quality in urbanized areas: A case study from Lithuania

    NASA Astrophysics Data System (ADS)

    Klimas, A. A.

    1996-06-01

    Cities have a negative impact on the quality of shallow groundwater. Many of Lithuania's urban residents drink water from dug wells. Moreover, polluted shallow groundwater contaminates deeper aquifers of fresh drinking water. Therefore, this situation should be controlled and managed, as far as possible. In order to evaluate the quality of shallow groundwater in an urban area and to create an optimal monitoring system, an original methodology for groundwater mapping has been proposed. It resembles the GIS (geographical information system) technologies. The set of maps, laid one over another, consists of the following: (1) urbanization map, (2) geological-hydrogeological map, (3) groundwater chemistry map, (4) resulting groundwater chemistry factorial analysis map, and (5) pollution and pollutant transport map. The data obtained from studies on dug and geotechnical wells have been used for compilation of the maps. The system for shallow groundwater monitoring in the city with an area of 70 sq km and a population of 140,000 is proposed to consist of about 30 monitoring wells and several dug wells.

  11. A double-mutant collection targeting MAP kinase related genes in Arabidopsis for studying genetic interactions.

    PubMed

    Su, Shih-Heng; Krysan, Patrick J

    2016-12-01

    Mitogen-activated protein kinase cascades are conserved in all eukaryotes. In Arabidopsis thaliana there are approximately 80 genes encoding MAP kinase kinase kinases (MAP3K), 10 genes encoding MAP kinase kinases (MAP2K), and 20 genes encoding MAP kinases (MAPK). Reverse genetic analysis has failed to reveal abnormal phenotypes for a majority of these genes. One strategy for uncovering gene function when single-mutant lines do not produce an informative phenotype is to perform a systematic genetic interaction screen whereby double-mutants are created from a large library of single-mutant lines. Here we describe a new collection of 275 double-mutant lines derived from a library of single-mutants targeting genes related to MAP kinase signaling. To facilitate this study, we developed a high-throughput double-mutant generating pipeline using a system for growing Arabidopsis seedlings in 96-well plates. A quantitative root growth assay was used to screen for evidence of genetic interactions in this double-mutant collection. Our screen revealed four genetic interactions, all of which caused synthetic enhancement of the root growth defects observed in a MAP kinase 4 (MPK4) single-mutant line. Seeds for this double-mutant collection are publicly available through the Arabidopsis Biological Resource Center. Scientists interested in diverse biological processes can now screen this double-mutant collection under a wide range of growth conditions in order to search for additional genetic interactions that may provide new insights into MAP kinase signaling.

  12. Quality and rigor of the concept mapping methodology: a pooled study analysis.

    PubMed

    Rosas, Scott R; Kane, Mary

    2012-05-01

    The use of concept mapping in research and evaluation has expanded dramatically over the past 20 years. Researchers in academic, organizational, and community-based settings have applied concept mapping successfully without the benefit of systematic analyses across studies to identify the features of a methodologically sound study. Quantitative characteristics and estimates of quality and rigor that may guide for future studies are lacking. To address this gap, we conducted a pooled analysis of 69 concept mapping studies to describe characteristics across study phases, generate specific indicators of validity and reliability, and examine the relationship between select study characteristics and quality indicators. Individual study characteristics and estimates were pooled and quantitatively summarized, describing the distribution, variation and parameters for each. In addition, variation in the concept mapping data collection in relation to characteristics and estimates was examined. Overall, results suggest concept mapping yields strong internal representational validity and very strong sorting and rating reliability estimates. Validity and reliability were consistently high despite variation in participation and task completion percentages across data collection modes. The implications of these findings as a practical reference to assess the quality and rigor for future concept mapping studies are discussed.

  13. History and future of the Multidisciplinary Association for Psychedelic Studies (MAPS).

    PubMed

    Emerson, Amy; Ponté, Linnae; Jerome, Lisa; Doblin, Rick

    2014-01-01

    This article describes the teenage vision of the founder of the Multidisciplinary Association for Psychedelic Studies (MAPS) that humanity's future would be aided by the therapeutic and spiritual potential of psychedelic substances. The article traces the trajectory of MAPS from inception in 1986 to its present, noting future goals with respect to research, outreach, and harm reduction. MAPS was created as a non-profit psychedelic pharmaceutical company in response to the 1985 scheduling of 3,4-methylenedioxymethamphetamine (MDMA). Overcoming many hurdles, MAPS developed the first double-blind, placebo-controlled trial of MDMA-assisted psychotherapy for posttraumatic stress disorder (PTSD) and plans for FDA prescription approval in 2021. MAPS' program of research expanded to include a trial of lysergic acid diethylamide (LSD)-assisted psychotherapy for anxiety when facing life-threatening illness, observational studies of ibogaine in the treatment of addiction, and studies of MDMA for social anxiety in people with autism spectrum disorders. MAPS meets the challenges of drug development through a clinical research team led by a former Novartis drug development professional experienced in the conduct, monitoring, and analysis of clinical trials. MAPS' harm-reduction efforts are intended to avoid backlash and build a post-prohibition world by assisting non-medical users to transform difficult psychedelic experiences into opportunities for growth.

  14. Thinking Maps: An innovative way to increase sixth-grade student achievement in social studies

    NASA Astrophysics Data System (ADS)

    Reed, Tamita

    The purpose of this quantitative study was to determine the effect of Thinking Maps on the achievement of 6th-grade social studies students in order to determine its effectiveness. The population of this study came from a suburban middle school in the state of Georgia. The quantitative data included a pretest and posttest. The study was designed to find (a) whether there is a significant difference between the mean posttest scores on the benchmark test of 6th-grade students who are taught with either Thinking Maps or traditional social studies methods, (b) whether there is a significant difference between the mean posttest scores on the benchmark test of 6th-grade male versus female social studies students, and (c) whether there is a significant interaction between 6th-grade students' type of social studies class and gender as to differentially affect their mean posttest scores on the benchmark test. To answer these questions, students' pretest and posttest were compared to determine if there was a statistically significant difference after Thinking Maps were implemented with the treatment group for 9 weeks. The results indicate that there was no significant difference in the test scores between the students who were taught with Thinking Maps and the students who were taught without Thinking Maps. However, the students taught with Thinking Maps had the higher adjusted posttest scores.

  15. USGS maps

    USGS Publications Warehouse

    ,

    2005-01-01

    Discover a small sample of the millions of maps produced by the U.S. Geological Survey (USGS) in its mission to map the Nation and survey its resources. This booklet gives a brief overview of the types of maps sold and distributed by the USGS through its Earth Science Information Centers (ESIC) and also available from business partners located in most States. The USGS provides a wide variety of maps, from topographic maps showing the geographic relief and thematic maps displaying the geology and water resources of the United States, to special studies of the moon and planets.

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

    PubMed

    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.

  17. Extension of the operating period of an UV Cu II laser by admixture of argon

    SciTech Connect

    Auschwitz, B.; Eichler, H.J.; Wittwer, W.

    1980-05-15

    The operating period of an UV Cu II laser (discharge current >25 A, duty cycle 6:1) is extended from minutes to over one hour by an admixture of 0.1% argon to the neon pump gas. In addition, a new laser line at 270.1 nm has been observed.

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

    ERIC Educational Resources Information Center

    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…

  19. Phenomenological model of sintering of oxide nuclear fuel with doping admixtures

    SciTech Connect

    Baranov, V. G.; Devyatko, Yu. N.; Tenishev, A. V.; Khomyakov, O. V.

    2015-12-15

    It is shown that a change in the linear dimension of compacted UO{sub 2} in the sintering process is associated with its plastic yielding under the action of the forces of residual stress and capillary forces. From the curves of sintering of a fuel with doping admixtures in various gaseous media, its rate of creep is reduced.

  20. Dynamic processes and their influence on the transformation of the passive admixture in the sea of Azov

    NASA Astrophysics Data System (ADS)

    Ivanov, V. A.; Cherkesov, L. V.; Shul'ga, T. Ya.

    2014-07-01

    In this model, we apply a nonlinear three-dimensional sigma-coordinate model to study the waves and currents in the Sea of Azov generated by different fields of wind forcing: a constant wind, a quickly varying real wind obtained using the data of reanalysis applying the SKIRON model, and the wind resulting from their combined forcing. This mathematical model was also applied to study the transformation of the passive admixture appearing under the influence of wind fields in the Sea of Azov considered here. We compared the results of numerical calculations with the field data obtained under the wind forcing at a number of hydrological stations. We found the regularities of the water transport driven by onshore and offshore winds, the velocities of the currents, and the characteristics of the evolution of polluted regions at different depths as functions of the nonstationary wind intensity and the velocities of the stationary currents.

  1. WWC Quick Review of "Retrieval Practice Produces More Learning than Elaborative Studying with Concept Mapping"

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2011

    2011-01-01

    The study examined whether using the retrieval-practice studying technique--in which students alternate between reading a passage and writing memorable information from that passage--improved student learning of a science passage more than the study-once, repeated-study, or concept-mapping techniques. The study found that students using the…

  2. Mapping Multi-Day GPS Data: A Cartographic Study in NYC.

    PubMed

    Duncan, Dustin T; Regan, Seann D

    Multi-day GPS data is increasingly being used in research-including in the field of spatial epidemiology. We present several maps as ways to present multi-day GPS data. Data come from the NYC Low-Income Housing, Neighborhoods and Health Study (n=120). Participants wore a QStarz BT-Q1000XT GPS device for about a week (mean: 7.44, SD= 2.15). Our maps show various ways to visualize multi-day GPS data; these data are presented by overall GPS data, by weekday/weekend and by day of the week. We discuss implications for each of the maps.

  3. A novel triangle mapping technique to study the h-index based citation distribution.

    PubMed

    Zhang, Chun-Ting

    2013-01-01

    The h-index has received wide attention in recent years. The area under the citation function is divided by the h-index into three parts, representing h-squared, excess and h-tail citations. The h-index by itself does not carry information for excess and h-tail citations, which can play an even more dominant role than h-index in determining the citation curve, and therefore it is necessary to examine the relations among them. A triangle mapping technique is proposed here to map the three percentages of these citations onto a point within a regular triangle. By viewing the distribution of mapping points, shapes of the citation functions can be studied in a perceivable form. As an example, the distribution of the mapping points for 100 most prolific economists is studied by this technique.

  4. Characterizing semantic mappings adaptation via biomedical KOS evolution: a case study investigating SNOMED CT and ICD.

    PubMed

    Dos Reis, Julio Cesar; Pruski, Cédric; Da Silveira, Marcos; Reynaud-Delaître, Chantal

    2013-01-01

    Mappings established between Knowledge Organization Systems (KOS) increase semantic interoperability between biomedical information systems. However, biomedical knowledge is highly dynamic and changes affecting KOS entities can potentially invalidate part or the totality of existing mappings. Understanding how mappings evolve and what the impacts of KOS evolution on mappings are is therefore crucial for the definition of an automatic approach to maintain mappings valid and up-to-date over time. In this article, we study variations of a specific KOS complex change (split) for two biomedical KOS (SNOMED CT and ICD-9-CM) through a rigorous method of investigation for identifying and refining complex changes, and for selecting representative cases. We empirically analyze and explain their influence on the evolution of associated mappings. Results point out the importance of considering various dimensions of the information described in KOS, like the semantic structure of concepts, the set of relevant information used to define the mappings and the change operations interfering with this set of information.

  5. Characterizing Semantic Mappings Adaptation via Biomedical KOS Evolution: A Case Study Investigating SNOMED CT and ICD

    PubMed Central

    Reis, Julio Cesar Dos; Pruski, Cédric; Da Silveira, Marcos; Reynaud-Delaître, Chantal

    2013-01-01

    Mappings established between Knowledge Organization Systems (KOS) increase semantic interoperability between biomedical information systems. However, biomedical knowledge is highly dynamic and changes affecting KOS entities can potentially invalidate part or the totality of existing mappings. Understanding how mappings evolve and what the impacts of KOS evolution on mappings are is therefore crucial for the definition of an automatic approach to maintain mappings valid and up-to-date over time. In this article, we study variations of a specific KOS complex change (split) for two biomedical KOS (SNOMED CT and ICD-9-CM) through a rigorous method of investigation for identifying and refining complex changes, and for selecting representative cases. We empirically analyze and explain their influence on the evolution of associated mappings. Results point out the importance of considering various dimensions of the information described in KOS, like the semantic structure of concepts, the set of relevant information used to define the mappings and the change operations interfering with this set of information. PMID:24551341

  6. Advantage of spatial map ion imaging in the study of large molecule photodissociation

    NASA Astrophysics Data System (ADS)

    Lee, Chin; Lin, Yen-Cheng; Lee, Shih-Huang; Lee, Yin-Yu; Tseng, Chien-Ming; Lee, Yuan-Tseh; Ni, Chi-Kung

    2017-07-01

    The original ion imaging technique has low velocity resolution, and currently, photodissociation is mostly investigated using velocity map ion imaging. However, separating signals from the background (resulting from undissociated excited parent molecules) is difficult when velocity map ion imaging is used for the photodissociation of large molecules (number of atoms ≥ 10). In this study, we used the photodissociation of phenol at the S1 band origin as an example to demonstrate how our multimass ion imaging technique, based on modified spatial map ion imaging, can overcome this difficulty. The photofragment translational energy distribution obtained when multimass ion imaging was used differed considerably from that obtained when velocity map ion imaging and Rydberg atom tagging were used. We used conventional translational spectroscopy as a second method to further confirm the experimental results, and we conclude that data should be interpreted carefully when velocity map ion imaging or Rydberg atom tagging is used in the photodissociation of large molecules. Finally, we propose a modified velocity map ion imaging technique without the disadvantages of the current velocity map ion imaging technique.

  7. Straightforward inference of ancestry and admixture proportions through ancestry-informative insertion deletion multiplexing.

    PubMed

    Pereira, Rui; Phillips, Christopher; Pinto, Nádia; Santos, Carla; dos Santos, Sidney Emanuel Batista; Amorim, António; Carracedo, Ángel; Gusmão, Leonor

    2012-01-01

    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.

  8. Effect of coagulants on the quality of chhana and rasogolla obtained from admixture of buffalo milk and butter milk.

    PubMed

    Kumar, Jitendra; Gupta, V K; Kumar, Sanjeev; Kumar, Suryamani

    2015-03-01

    A study was carried out to investigate the effect of different coagulant (lactic acid, citric acid and calcium lactate) on yield, sensory and textural characteristics of chhana and rasogolla made from admixture of buffalo milk and sweet cream butter milk (SCBM). The highest yield of chhana was observed with calcium lactate whereas the minimum yield was found with citric acid. There was no significant difference found with respect to flavour and colour and appearances scores, however, significant (p < 0.01) difference found in body and texture of chhana samples prepared with different coagulant. In addition to that, significant (p < 0.05) difference observed with respect to body and texture, flavour and porosity of rasogolla, but no significant difference was observed in colour and appearance as well as sweetness of rasogolla prepared with chhana obtained from varying coagulants. Among different coagulants, citric acid was found best suitable for chhana as well as rasogolla making.

  9. Research on Integrated Mapping——A Case Study of Integrated Land Use with Swamp Mapping

    NASA Astrophysics Data System (ADS)

    Zhang, S.; Yan, F.; Chang, L.

    2015-12-01

    Unified real estate registration system shows the attention, determination and effort to of CPC Central Committee and State Council on real estate registration in China. However, under current situation, China's real estate registration work made less progress. One of the reasons is that it's hard to express the property right of real estate on one map under the multi-sector management system. Under current multi-sector management system in China, different departments usually just survey and mapping the land type under its jurisdiction. For example, wetland investigation only mapping all kinds of wetland resources but not mapping other resource types. As a result, it cause he problem of coincidence or leak in integration of different results from different departments. As resources of the earth's surface, the total area of forest, grassland, wetland and so on should be equal to the total area of the earth's surface area. However, under the current system, the area of all kinds of resources is not equal to the sum of the earth's surface. Therefore, it is of great importance to express all the resources on one map. On one hand, this is conducive to find out the real area and distribution of resources and avoid the problem of coincidence or leak in integration; On the other hand, it is helpful to study the dynamic change of different resources. Therefore, we first proposed the "integrated mapping" as a solution, and take integrated land use with swamp mapping in Northeast China as an example to investigate the feasibility and difficulty. Study showed that: integrated land use with swamp mapping can be achieved through combining land use survey standards with swamps survey standards and "second mapping" program. Based on the experience of integrated land use with swamp mapping, we point out its reference function on integrated mapping and unified real estate registration system. We concluded that: (1) Comprehending and integrating different survey standard of

  10. Compounding times and contamination rates associated with the preparation of intravenous admixtures in three types of plastic containers.

    PubMed

    Allinson, R R; Stach, P E; Sherrin, T P; Latiolais, C J

    1979-04-01

    The compounding times and contamination rates associated with the preparation of admixtures in three different plastic i.v. containers of dextrose 5% in water were compared. The time required for a technician to prepare, in a laminar air flow hood by the needle and syringe technique, 120 admixtures in each of three different plastic i.v. containers was measured and recorded by two investigators. The 360 admixtures were tested within one hour of preparation for sterility using an enriched brain heart infusion broth. The total time required to compound the i.v. admixtures varied significantly with container design (p less than 0.01), preparation being fastest with the Accumed container, followed by the LifeCare then the Viaflex containers. The major contributing factors to increased compounding time were (1) removal of outer wrap, (2) swabbing of LifeCare and Viaflex medication ports with isopropyl alcohol pads and (3) freeing of the hangar flap from the Viaflex container. Sterility tests revealed no detectable contamination of any of the admixtures. Container design of plastic i.v. containers did influence the preparation time for admixtures but did not influence admixture sterility.

  11. Study Abroad and the City: Mapping Urban Identity

    ERIC Educational Resources Information Center

    Blair, Scott

    2011-01-01

    Study abroad by U.S. students, despite recent growth into non-western and rural destinations, often remains focused on cities, often very large and highly urbanized ones. While the destination cities for study abroad are located across the globe, European cities remain predominant, and thus, this article focuses on study abroad in one city. The…

  12. Detecting introgressive hybridization between free-ranging domestic dogs and wild wolves (Canis lupus) by admixture linkage disequilibrium analysis.

    PubMed

    Verardi, A; Lucchini, V; Randi, E

    2006-09-01

    Occasional crossbreeding between free-ranging domestic dogs and wild wolves (Canis lupus) has been detected in some European countries by mitochondrial DNA sequencing and genotyping unlinked microsatellite loci. Maternal and unlinked genomic markers, however, might underestimate the extent of introgressive hybridization, and their impacts on the preservation of wild wolf gene pools. In this study, we genotyped 220 presumed Italian wolves, 85 dogs and 7 known hybrids at 16 microsatellites belonging to four different linkage groups (plus four unlinked microsatellites). Population clustering and individual assignments were performed using a Bayesian procedure implemented in structure 2.1, which models the gametic disequilibrium arising between linked loci during admixtures, aiming to trace hybridization events further back in time and infer the population of origin of chromosomal blocks. Results indicate that (i) linkage disequilibrium was higher in wolves than in dogs; (ii) 11 out of 220 wolves (5.0%) were likely admixed, a proportion that is significantly higher than one admixed genotype in 107 wolves found previously in a study using unlinked markers; (iii) posterior maximum-likelihood estimates of the recombination parameter r revealed that introgression in Italian wolves is not recent, but could have continued for the last 70 (+/- 20) generations, corresponding to approximately 140-210 years. Bayesian clustering showed that, despite some admixture, wolf and dog gene pools remain sharply distinct (the average proportions of membership to wolf and dog clusters were Q(w) = 0.95 and Q(d) = 0.98, respectively), suggesting that hybridization was not frequent, and that introgression in nature is counteracted by behavioural or selective constraints.

  13. Population structure and paternal admixture landscape on present-day Mexican-Mestizos revealed by Y-STR haplotypes.

    PubMed

    Salazar-Flores, J; Dondiego-Aldape, R; Rubi-Castellanos, R; Anaya-Palafox, M; Nuño-Arana, I; Canseco-Avila, L M; Flores-Flores, G; Morales-Vallejo, M E; Barojas-Pérez, N; Muñoz-Valle, J F; Campos-Gutiérrez, R; Rangel-Villalobos, H

    2010-01-01

    Mestizos currently represent most of the Mexican population (>90%); they are defined as individuals born in the country having a Spanish-derived last name, with family antecedents of Mexican ancestors back at least to the third generation. Mestizos are result of 500 years of admixture mainly among Spaniards, Amerindians, and African slaves. Consequently, a complex genetic pattern has been generated throughout the country that has been scarcely studied from the paternal point of view. This fact is important, taking into account that gene flow toward the New World comprised largely males. We analyzed the population structure and paternal admixture of present-day Mexican-Mestizo populations based on Y-STRs. We genotyped at least 12 Y-STRs in DNA samples of 986 males from five states: Aguascalientes (n = 293); Jalisco (n = 185); Guanajuato (n = 168); Chiapas (n = 170); and Yucatán (n = 170). AmpFlSTR Y-filer and Powerplex-Y(R) kits were used. Inclusion of North and Central Y-STR databases in the analyses allowed obtaining a Y-STR variability landscape from Mexico. Results confirmed the population differentiation gradient previously noted in Mestizos with SNPs and autosomal STRs throughout the Mexican territory: European ancestry increments to the Northwest and, correspondingly, Amerindian ancestry increments to the Center and Southeast. In addition, SAMOVA test and Autocorrelation Index for DNA Analysis autocorrelogram plot suggested preferential gene flow of males with neighboring populations in agreement with the isolation-by-distance model. Results are important for disease-risk studies (principally male-related) and for human identification purposes, because Y-STR databases are not available on the majority of Mexican-Mestizo populations.

  14. Genome-wide patterns of population structure and admixture in West Africans and African Americans.

    PubMed

    Bryc, Katarzyna; Auton, Adam; Nelson, Matthew R; Oksenberg, Jorge R; Hauser, Stephen L; Williams, Scott; Froment, Alain; Bodo, Jean-Marie; Wambebe, Charles; Tishkoff, Sarah A; Bustamante, Carlos D

    2010-01-12

    Quantifying patterns of population structure in Africans and African Americans illuminates the history of human populations and is critical for undertaking medical genomic studies on a global scale. To obtain a fine-scale genome-wide perspective of ancestry, we analyze Affymetrix GeneChip 500K genotype data from African Americans (n = 365) and individuals with ancestry from West Africa (n = 203 from 12 populations) and Europe (n = 400 from 42 countries). We find that population structure within the West African sample reflects primarily language and secondarily geographical distance, echoing the Bantu expansion. Among African Americans, analysis of genomic admixture by a principal component-based approach indicates that the median proportion of European ancestry is 18.5% (25th-75th percentiles: 11.6-27.7%), with very large variation among individuals. In the African-American sample as a whole, few autosomal regions showed exceptionally high or low mean African ancestry, but the X chromosome showed elevated levels of African ancestry, consistent with a sex-biased pattern of gene flow with an excess of European male and African female ancestry. We also find that genomic profiles of individual African Americans afford personalized ancestry reconstructions differentiating ancient vs. recent European and African ancestry. Finally, patterns of genetic similarity among inferred African segments of African-American genomes and genomes of contemporary African populations included in this study suggest African ancestry is most similar to non-Bantu Niger-Kordofanian-speaking populations, consistent with historical documents of the African Diaspora and trans-Atlantic slave trade.

  15. On the feasibility of tracking with differential-algebra maps in long-term stability studies for large hadron colliders

    SciTech Connect

    Kleiss, R.; Schmidt, F.; Yan, Y.

    1992-01-01

    A time-saving alternative to conventional element-by-element tracking in long-term stability studies is the use of truncated Taylor maps. This report discusses how the non-symplecticity of a moderately high-order truncated Taylor map affects its reliability when the map is used for tracking over several thousand turns. Various machines and two different map-constructing programs are compared. It is found that the discrepancies between the Taylor map results and those obtained by direct tracking grow with amplitude. Thus, such maps are not guaranteed to be sufficient for long-term tracking over millions of turns without suitable symplectification.

  16. [May Medically Assisted Procreation (MAP) be relevant for homosexual women? Study among 147 gynaeco-logists involved in MAP techniques].

    PubMed

    Sintes, R; Darves-Bornoz, J-M

    2002-01-01

    The second part of the twentieth century has seen societal modifications as well as evolution of medical techniques allowing now thinking human procreation in terms of choices or even rights. Certain voices require sometimes Medically Assisted Procreation (MAP) for lesbians. Even though society did not allow such a possibility in France, it seemed interesting to question about it professionals actively involved in the use of MAP techniques. Through systematic internet queries, we obtained a list of one hundred private or public french medical institutions with a unit for the treatment of sterility. A telephone call to their secretary allowed us to individualize those doctors who did practice MAP. A sample of 147 medical doctors practicing MAP was then drawn. They were questioned with a clinical instrument including 20 ended-questions in order to assess their opinions on: homosexual women with a desire of a child; possibility for these clinicians to intervene with a donor insemination in such situations; developmental risk for such children. One hundred twenty five (85%) accepted to answer. Nine percent of these gynaecologists still consider homosexuality as pathological, and 10% as deviant - contrary to international classifications of mental disorders - and 5% deny good maternal abilities to homosexual women. Before the so-called french laws of bioethics in 1994, none of them had practiced a donor insemination for a lesbian couple, though 4% had realized some for single homosexual women. Two third of them do not agree opening donor insemination to homosexual women though for half of them, the anonymity of a donor is not perceived as prejudicial to the child. Eighty-seven percent of these gynaecologists think that a child brought up by homosexual parents is at risk for developmental disorder, the configuration supposed the most pathogenic being when the birth results from a donor insemination. The supposedly most important risk factors are thought to be the

  17. Sub-pixel mapping of water boundaries using pixel swapping algorithm (case study: Tagliamento River, Italy)

    NASA Astrophysics Data System (ADS)

    Niroumand-Jadidi, Milad; Vitti, Alfonso

    2015-10-01

    Taking the advantages of remotely sensed data for mapping and monitoring of water boundaries is of particular importance in many different management and conservation activities. Imagery data are classified using automatic techniques to produce maps entering the water bodies' analysis chain in several and different points. Very commonly, medium or coarse spatial resolution imagery is used in studies of large water bodies. Data of this kind is affected by the presence of mixed pixels leading to very outstanding problems, in particular when dealing with boundary pixels. A considerable amount of uncertainty inescapably occurs when conventional hard classifiers (e.g., maximum likelihood) are applied on mixed pixels. In this study, Linear Spectral Mixture Model (LSMM) is used to estimate the proportion of water in boundary pixels. Firstly by applying an unsupervised clustering, the water body is identified approximately and a buffer area considered ensuring the selection of entire boundary pixels. Then LSMM is applied on this buffer region to estimate the fractional maps. However, resultant output of LSMM does not provide a sub-pixel map corresponding to water abundances. To tackle with this problem, Pixel Swapping (PS) algorithm is used to allocate sub-pixels within mixed pixels in such a way to maximize the spatial proximity of sub-pixels and pixels in the neighborhood. The water area of two segments of Tagliamento River (Italy) are mapped in sub-pixel resolution (10m) using a 30m Landsat image. To evaluate the proficiency of the proposed approach for sub-pixel boundary mapping, the image is also classified using a conventional hard classifier. A high resolution image of the same area is also classified and used as a reference for accuracy assessment. According to the results, sub-pixel map shows in average about 8 percent higher overall accuracy than hard classification and fits very well in the boundaries with the reference map.

  18. Phylogeographic Analyses of American Black Bears (Ursus americanus) Suggest Four Glacial Refugia and Complex Patterns of Postglacial Admixture.

    PubMed

    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.

  19. Genome-wide analysis reveals the ancient and recent admixture history of East African Shorthorn Zebu from Western Kenya

    PubMed Central

    Mbole-Kariuki, M N; Sonstegard, T; Orth, A; Thumbi, S M; Bronsvoort, B M de C; Kiara, H; Toye, P; Conradie, I; Jennings, A; Coetzer, K; Woolhouse, M E J; Hanotte, O; Tapio, M

    2014-01-01

    The Kenyan East African zebu cattle are valuable and widely used genetic resources. Previous studies using microsatellite loci revealed the complex history of these populations with the presence of taurine and zebu genetic backgrounds. Here, we estimate at genome-wide level the genetic composition and population structure of the East African Shorthorn Zebu (EASZ) of western Kenya. A total of 548 EASZ from 20 sub-locations were genotyped using the Illumina BovineSNP50 v. 1 beadchip. STRUCTURE analysis reveals admixture with Asian zebu, African and European taurine cattle. The EASZ were separated into three categories: substantial (⩾12.5%), moderate (1.56%admixture in the EASZ population, subsequently shaped by selection and/or genetic drift, followed by a more recent exotic European cattle introgression. PMID:24736786

  20. The biologistical construction of race: 'admixture' technology and the new genetic medicine.

    PubMed

    Fullwiley, Duana

    2008-10-01

    This paper presents an ethnographic case study of the use of race in two interconnected laboratories of medical genetics. Specifically, it examines how researchers committed to reducing health disparities in Latinos with asthma advance hypotheses and structure research to show that relative frequencies of genetic markers characterize commonly understood groupings of race. They do this first by unapologetically advancing the idea that peoples whom they take to be of the 'Old World', or 'Africans', 'Europeans', 'East Asians', and 'Native Americans', can serve as putatively pure reference populations against which genetic risk for common diseases such as asthma can be calculated for those in the 'New World'. Technologically, they deploy a tool called ancestry informative markers (AIMs), which are a collection of genetic sequence variants said to differ in present-day West Africans, East Asians, Europeans, and (ideally Pre-Columbian) Native Americans. I argue that this technology, compelling as it may be to a range of actors who span the political spectrum, is, at base, designed to bring about a correspondence of familiar ideas of race and supposed socially neutral DNA. This correspondence happens, in part, as the scientists in question often bracket the environment while privileging racialized genetic variance as the primary source of health disparities for common disease, in this case between Mexicans and Puerto Ricans with asthma. With their various collaborators, these scientists represent a growing movement within medical genetics to re-consider race and 'racial admixture' as biogenetically valid points of departure. Furthermore, many actors at the center of this ethnography focus on race as a function of their personal identity politics as scientists of color. This to say, they are driven not by racist notions of human difference, but by a commitment to reduce health disparities and to include 'their' communities in what they describe as the 'genetic revolution'.

  1. Coagulated silica - a-SiO2 admixture in cement paste

    NASA Astrophysics Data System (ADS)

    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.

  2. Meeting the Demands of Professional Education: A Study of Mind Mapping in a Professional Doctoral Physical Therapy Education Program

    ERIC Educational Resources Information Center

    Pollard, Elicia L.

    2010-01-01

    The purposes of this study are to investigate whether the quiz scores of physical therapy students who integrated mind mapping in their learning strategies are significantly different than the quiz scores of students who did not use mind mapping to learn in a lecture-based research course and examine the students' perceptions of mind mapping as a…

  3. Engineering Feasibility and Trade Studies for the NASA/VSGC MicroMaps Space Mission

    NASA Technical Reports Server (NTRS)

    Abdelkhalik, Ossama O.; Nairouz, Bassem; Weaver, Timothy; Newman, Brett

    2003-01-01

    Knowledge of airborne CO concentrations is critical for accurate scientific prediction of global scale atmospheric behavior. MicroMaps is an existing NASA owned gas filter radiometer instrument designed for space-based measurement of atmospheric CO vertical profiles. Due to programmatic changes, the instrument does not have access to the space environment and is in storage. MicroMaps hardware has significant potential for filling a critical scientific need, thus motivating concept studies for new and innovative scientific spaceflight missions that would leverage the MicroMaps heritage and investment, and contribute to new CO distribution data. This report describes engineering feasibility and trade studies for the NASA/VSGC MicroMaps Space Mission. Conceptual studies encompass: 1) overall mission analysis and synthesis methodology, 2) major subsystem studies and detailed requirements development for an orbital platform option consisting of a small, single purpose spacecraft, 3) assessment of orbital platform option consisting of the International Space Station, and 4) survey of potential launch opportunities for gaining assess to orbit. Investigations are of a preliminary first-order nature. Results and recommendations from these activities are envisioned to support future MicroMaps Mission design decisions regarding program down select options leading to more advanced and mature phases.

  4. Mapping Task Switching in Frontal Cortex Through Neuropsychological Group Studies

    PubMed Central

    Shallice, Tim; Stuss, Donald T.; Picton, Terence W.; Alexander, Michael P.; Gillingham, Susan

    2008-01-01

    This paper considers evidence provided by large neuropsychological group studies and meta-analyses of functional imaging experiments on the location in frontal cortex of the subprocesses involved in the carrying out of task-switching paradigms. The function of the individual subprocesses is also considered in the light of analyses of the performance of normal subjects. PMID:18982110

  5. IMMUNOCAT-a data management system for epitope mapping studies.

    PubMed

    Chung, Jo L; Sun, Jian; Sidney, John; Sette, Alessandro; Peters, Bjoern

    2010-01-01

    To enable rationale vaccine design, studies of molecular and cellular mechanisms of immune recognition need to be linked with clinical studies in humans. A major challenge in conducting such translational research studies lies in the management and integration of large amounts and various types of data collected from multiple sources. For this purpose, we have established "IMMUNOCAT", an interactive data management system for the epitope discovery research projects conducted by our group. The system provides functions to store, query, and analyze clinical and experimental data, enabling efficient, systematic, and integrative data management. We demonstrate how IMMUNOCAT is utilized in a large-scale research contract that aims to identify epitopes in common allergens recognized by T cells from human donors, in order to facilitate the rational design of allergy vaccines. At clinical sites, demographic information and disease history of each enrolled donor are captured, followed by results of an allergen skin test and blood draw. At the laboratory site, T cells derived from blood samples are tested for reactivity against a panel of peptides derived from common human allergens. IMMUNOCAT stores results from these T cell assays along with MHC:peptide binding data, results from RAST tests for antibody titers in donor serum, and the respective donor HLA typing results. Through this system, we are able to perform queries and integrated analyses of the various types of data. This provides a case study for the use of bioinformatics and information management techniques to track and analyze data produced in a translational research study aimed at epitope identification.

  6. A study of an orbital radar mapping mission to Venus. Volume 3: Parametric studies and subsystem comparisons

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Parametric studies and subsystem comparisons for the orbital radar mapping mission to planet Venus are presented. Launch vehicle requirements and primary orbiter propulsion system requirements are evaluated. The systems parametric analysis indicated that orbit size and orientation interrelated with almost all of the principal spacecraft systems and influenced significantly the definition of orbit insertion propulsion requirements, weight in orbit capability, radar system design, and mapping strategy.

  7. Spatial memory extinction: a c-Fos protein mapping study.

    PubMed

    Méndez-Couz, M; Conejo, N M; Vallejo, G; Arias, J L

    2014-03-01

    While the neuronal basis of spatial memory consolidation has been thoroughly studied, the substrates mediating the process of extinction remain largely unknown. This study aimed to evaluate the functional contribution of selected brain regions during the extinction of a previously acquired spatial memory task in the Morris water maze. For that purpose, we used adult male Wistar rats trained in a spatial reference memory task. Learning-related changes in c-Fos inmunoreactive cells after training were evaluated in cortical and subcortical regions. Results show that removal of the hidden platform in the water maze induced extinction of the previously reinforced escape behavior after 16 trials, without spontaneous recovery 24h later. Extinction was related with significantly higher numbers of c-Fos positive nuclei in amygdala nuclei and prefrontal cortex. On the other hand, the lateral mammillary bodies showed higher number of c-Fos positive cells than the control group. Therefore, in contrast with the results obtained in studies of classical conditioning, we show the involvement of diencephalic structures mediating this kind of learning. In summary, our findings suggest that medial prefrontal cortex, the amygdala complex and diencephalic structures like the lateral mammillary nuclei are relevant for the extinction of spatial memory.

  8. Effects of concept map teaching on students' critical thinking and approach to learning and studying.

    PubMed

    Chen, Shiah-Lian; Liang, Tienli; Lee, Mei-Li; Liao, I-Chen

    2011-08-01

    The purpose of this study was to explore the effects of concept mapping in developing critical thinking ability and approach to learning and studying. A quasi-experimental study design with a purposive sample was drawn from a group of nursing students enrolled in a medical-surgical nursing course in central Taiwan. Students in the experimental group were taught to use concept mapping in their learning. Students in the control group were taught by means of traditional lectures. After the intervention, the experimental group had better overall critical thinking scores than did the control group, although the difference was not statistically significant. After controlling for the effects of age and the pretest score on critical thinking using analysis of covariance, the experimental group had significantly higher adjusted mean scores on inference and overall critical thinking compared with the control group. Concept mapping is an effective tool for improving students' ability to think critically.

  9. Applying Value Stream Mapping Technique for Production Improvement in a Manufacturing Company: A Case Study

    NASA Astrophysics Data System (ADS)

    Jeyaraj, K. L.; Muralidharan, C.; Mahalingam, R.; Deshmukh, S. G.

    2013-01-01

    The purpose of this paper is to explain how value stream mapping (VSM) is helpful in lean implementation and to develop the road map to tackle improvement areas to bridge the gap between the existing state and the proposed state of a manufacturing firm. Through this case study, the existing stage of manufacturing is mapped with the help of VSM process symbols and the biggest improvement areas like excessive TAKT time, production, and lead time are identified. Some modifications in current state map are suggested and with these modifications future state map is prepared. Further TAKT time is calculated to set the pace of production processes. This paper compares the current state and future state of a manufacturing firm and witnessed 20 % reduction in TAKT time, 22.5 % reduction in processing time, 4.8 % reduction in lead time, 20 % improvement in production, 9 % improvement in machine utilization, 7 % improvement in man power utilization, objective improvement in workers skill level, and no change in the product and semi finished product inventory level. The findings are limited due to the focused nature of the case study. This case study shows that VSM is a powerful tool for lean implementation and allows the industry to understand and continuously improve towards lean manufacturing.

  10. Feasibility study of geospatial mapping of chronic disease risk to inform public health commissioning

    PubMed Central

    Smith, Dianna; Mathur, Rohini; Robson, John; Greenhalgh, Trisha

    2012-01-01

    Objective To explore the feasibility of producing small-area geospatial maps of chronic disease risk for use by clinical commissioning groups and public health teams. Study design Cross-sectional geospatial analysis using routinely collected general practitioner electronic record data. Sample and setting Tower Hamlets, an inner-city district of London, UK, characterised by high socioeconomic and ethnic diversity and high prevalence of non-communicable diseases. Methods The authors used type 2 diabetes as an example. The data set was drawn from electronic general practice records on all non-diabetic individuals aged 25–79 years in the district (n=163 275). The authors used a validated instrument, QDScore, to calculate 10-year risk of developing type 2 diabetes. Using specialist mapping software (ArcGIS), the authors produced visualisations of how these data varied by lower and middle super output area across the district. The authors enhanced these maps with information on examples of locality-based social determinants of health (population density, fast food outlets and green spaces). Data were piloted as three types of geospatial map (basic, heat and ring). The authors noted practical, technical and information governance challenges involved in producing the maps. Results Usable data were obtained on 96.2% of all records. One in 11 adults in our cohort was at ‘high risk’ of developing type 2 diabetes with a 20% or more 10-year risk. Small-area geospatial mapping illustrated ‘hot spots’ where up to 17.3% of all adults were at high risk of developing type 2 diabetes. Ring maps allowed visualisation of high risk for type 2 diabetes by locality alongside putative social determinants in the same locality. The task of downloading, cleaning and mapping data from electronic general practice records posed some technical challenges, and judgement was required to group data at an appropriate geographical level. Information governance issues were time consuming

  11. The Algebro-geometric Study of Range Maps

    NASA Astrophysics Data System (ADS)

    Compagnoni, Marco; Notari, Roberto; Ruggiu, Andrea Alessandro; Antonacci, Fabio; Sarti, Augusto

    2017-02-01

    Localizing a radiant source is a problem of great interest to many scientific and technological research areas. Localization based on range measurements is at the core of technologies such as radar, sonar and wireless sensor networks. In this manuscript, we offer an in-depth study of the model for source localization based on range measurements obtained from the source signal, from the point of view of algebraic geometry. In the case of three receivers, we find unexpected connections between this problem and the geometry of Kummer's and Cayley's surfaces. Our work also gives new insights into the localization based on range differences.

  12. The Algebro-geometric Study of Range Maps

    NASA Astrophysics Data System (ADS)

    Compagnoni, Marco; Notari, Roberto; Ruggiu, Andrea Alessandro; Antonacci, Fabio; Sarti, Augusto

    2016-08-01

    Localizing a radiant source is a problem of great interest to many scientific and technological research areas. Localization based on range measurements is at the core of technologies such as radar, sonar and wireless sensor networks. In this manuscript, we offer an in-depth study of the model for source localization based on range measurements obtained from the source signal, from the point of view of algebraic geometry. In the case of three receivers, we find unexpected connections between this problem and the geometry of Kummer's and Cayley's surfaces. Our work also gives new insights into the localization based on range differences.

  13. Upstream silver source mapping - a case study in Stockholm, Sweden.

    PubMed

    Amneklev, Jennie; Bergbäck, Bo; Sörme, Louise; Lagerkvist, Ragnar

    2014-01-01

    Silver (Ag) can be a problem for wastewater treatment plants (WWTP) and their capability to use sewage sludge as a soil fertilizer. Due to a high accumulation rate in soils, the levels of Ag in the incoming water at the WWTP must be reduced. This study aims to identify major diffuse emission sources in the technosphere through a comprehensive substance flow analysis of Ag in Stockholm, Sweden. Large inflows and stocks of Ag were present in electrical and electronic goods and appliances as well as in jewellery and silverware. The total inflow was 3.2 tonnes (4.2 g/person), the total stock was 100 tonnes (140 g/person) and the total outflow was 330 kg (430 mg/person). Major identified Ag sources with emissions ending up in the WWTP (total 26 kg, 34 mg/person) were food, amalgam and beauty products (via urine and faeces, 12 mg/person or 11% of incoming amount), and textiles (via washing, 17 mg/person or 16% of incoming amount). This study explains approximately 35% of the total 80 kg Ag in the incoming water at Henriksdal WWTP in Stockholm. Plastic, photography and beauty products were identified as possible sources of Ag that need to be examined further.

  14. Pre-Service Teacher Beliefs on the Antecedents to Bullying: A Concept Mapping Study

    ERIC Educational Resources Information Center

    Lopata, Joel A.; Nowicki, Elizabeth A.

    2014-01-01

    In this study, researchers gathered Canadian pre-service teachers' beliefs on the antecedents to bullying. Concept mapping (Kane & Trochim, 2007) was used to analyze the data. This study's findings identified pre-service teachers to have accurate beliefs, inaccurate beliefs, and a lack of knowledge about the antecedents to bullying. Concept…

  15. Mapping the Journey from Home to School: A Study on Children's Representation of Space

    ERIC Educational Resources Information Center

    Thommen, Evelyne; Avelar, Silvania; Sapin, Veronique Zbinden; Perrenoud, Silvia; Malatesta, Dominique

    2010-01-01

    This paper describes a study conducted with 235 children from Brazil and Switzerland. The children, from 5 to 13 years of age, were asked to draw the journey they undertake every day from home to school. The purpose of the study is to understand the relationship between the cognitive development and map-drawing abilities of children in both…

  16. Multiple Application Propfan Study (MAPS): Advanced tactical transport

    NASA Technical Reports Server (NTRS)

    Newton, F. C.; Liebeck, R. H.; Mitchell, G. H.; Mooiweer, A.; Platte, M. M.; Toogood, T. L.; Wright, R. A.

    1986-01-01

    This study was conducted to ascertain potential benefits of a propfan propulsion system application to a blended wing/body military tactical transport. Based on a design cruise Mach no. of 0.75 for the design mission, the results indicate a significant advantage in various figures of merit for the propfan over those of a comparable technology turbofan. Although the propfan has a 1.6 percent greater takeoff gross weight, its life cycle cost is 5.3 percent smaller, partly because of a 27 percent smaller specific fuel consumption. When employed on alternate missions, the propfan configuration offers significantly improved flexibility and capability: an increase in sea level penetration distance of more than 100 percent, or in time-on-station of 24 percent, or in deployment payload of 38 percent.

  17. Consequences of meta-stable (177m)Lu admixture in (177)Lu for patient dosimetry.

    PubMed

    Konijnenberg, Mark W

    2015-01-01

    Lutetium-177 ((177)Lu) is a rare earth metal in the lanthanides series which decays by beta emission with a half life of 6.647 days to three excited states and the ground state of (177)Hf. When (177)Lu is produced by neutron capture in (176)Lu, inevitably an admixture is formed of the long-lived isomer (177)mLu. As its half-life of 160.4 days is so much longer than that of (177)Lu, concerns are raised on its possible enhancement in radiation dose to the patient treated with (177)Lu-DOTA-octreotate. This report evaluates this possible enhancement of the absorbed dose, based on the published pharmacokinetic profile of (177)Lu-DOTA-octreotate and assuming an admixture of 1 kBq (177)mLu /MBq (177)Lu (0.1%).

  18. Direct-to-Consumer Racial Admixture Tests and Beliefs About Essential Racial Differences

    PubMed Central

    Phelan, Jo C.; Link, Bruce G.; Zelner, Sarah; Yang, Lawrence H.

    2015-01-01

    Although at first relatively disinterested in race, modern genomic research has increasingly turned attention to racial variations. We examine a prominent example of this focus—direct-to-consumer racial admixture tests—and ask how information about the methods and results of these tests in news media may affect beliefs in racial differences. The reification hypothesis proposes that by emphasizing a genetic basis for race, thereby reifying race as a biological reality, the tests increase beliefs that whites and blacks are essentially different. The challenge hypothesis suggests that by describing differences between racial groups as continua rather than sharp demarcations, the results produced by admixture tests break down racial categories and reduce beliefs in racial differences. A nationally representative survey experiment (N = 526) provided clear support for the reification hypothesis. The results suggest that an unintended consequence of the genomic revolution may be to reinvigorate age-old beliefs in essential racial differences. PMID:25870464

  19. A comparative study on the co-existing attractors in the Gaussian map and its q-deformed version

    NASA Astrophysics Data System (ADS)

    Patidar, Vinod; Sud, K. K.

    2009-03-01

    In a recent study Jaganathan and Sinha [Jaganathan R, Sinha S. A q-deformed nonlinear map. Phys Lett A 2005;338:277-87] have introduced a scheme for the q-deformation of nonlinear maps using the logistic map as an example and shown that the q-logistic map exhibits a wide spectrum of dynamical behaviours including the co-existence of attractors (which is a rare phenomenon in one-dimensional maps). In this paper, we aim to analyze another famous one-dimensional map - the Gaussian map (a known one-dimensional map exhibiting co-existing attractors) subject to the same q-deformation scheme. We compare the dynamical behaviour of the Gaussian map and q-deformed Gaussian map with a special attention on the regions of the parameter space, where these maps exhibit co-existing attractors. An important conclusion of the present study is that the appearance of co-existing attractors for a particular choice of system parameters can be understood as a consequence of the presence of multiple fixed points in one-dimensional nonlinear maps; however the converse is not always true.

  20. Workability and strength attributes of RCC: Effects of different chemical admixtures and resulting paste

    NASA Astrophysics Data System (ADS)

    Hazaree, Chetan Vijaysingh

    Roller compacted concrete (RCC) is a drier consistency concrete proportioned with dense graded aggregates and has lesser paste content. Primarily owing to its drier consistency, the fresh and mechanical performances of RCC are distinctly different from conventional concretes. The objectives of this work were three fold. The first objective was to explain the anomalous behavior of fresh RCC in terms of different components of workability. The second objective was to explain the mechanisms of strength development in terms of paste quality and quantity. The final objective was to explain the roles of different chemical admixtures (water reducers, retarders, rheology modifiers, air entraining agents, dry cast products, etc.) in influencing the workability and strength performances of RCC. It is observed that the relative volume and quality of the paste, in addition to combined aggregate grading, affect the overall workability of mixtures. The workability of concrete is characterized in terms of cohesion, angle of internal friction, air content, compactibility, and consistency retention over time. Air content plays a decisive role in influencing the performances of concrete. The resulting mobility of the paste influences the compactibility, which in-turn decides the strength as well. RCC shows anomalous behavior in terms of mechanical strength as shown by deviations in the Abrams' law. It is argued that water-binder ratio is not a comprehensive parameter to explain the overall concrete behavior and trends. A significant body of knowledge is added in terms of the use of chemical admixtures in RCC. Atypical behaviors in influencing the fresh and hardened properties are explained by offering plausible mechanisms in terms of binder-admixture interactions. Irrespective of the admixture type, higher than normal dosages are required for RCC. Keywords: roller compacted concrete, aggregates, paste quality, paste quantity, water/binder, aggregate/binder, air, workability

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

    SciTech Connect

    Waugh, W.J.; Thiede, M.E.; Bates, D.J.

    1994-07-01

    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.

  2. A Study of Concept Mapping as an Instructional Intervention in an Undergraduate General Chemistry Calorimetry Laboratory

    NASA Astrophysics Data System (ADS)

    Stroud, Mary W.

    This investigation, rooted in both chemistry and education, considers outcomes occurring in a small-scale study in which concept mapping was used as an instructional intervention in an undergraduate calorimetry laboratory. A quasi-experimental, multiple-methods approach was employed since the research questions posed in this study warranted the use of both qualitative and quantitative perspectives and evaluations. For the intervention group of students, a convenience sample, post-lab concept maps, written discussions, quiz responses and learning surveys were characterized and evaluated. Archived quiz responses for non-intervention students were also analyzed for comparison. Students uniquely constructed individual concept maps containing incorrect, conceptually correct and "scientifically thin" calorimetry characterizations. Students more greatly emphasized mathematical relationships and equations utilized during the calorimetry experiment; the meaning of calorimetry concepts was demonstrated to a lesser extent.

  3. Study of an Open Web Mapping Service for ESA's Planetary Surface Data Sets

    NASA Astrophysics Data System (ADS)

    Manaud, N.; Hempen, B.; Heather, D.; Salgado, J.; Osuna, P.; Frigeri, A.

    2011-10-01

    The aim of this study is to understand how open GIS technology and standards can be used to manage, process, and stream the geospatial content of the PSA archive across the Internet into existing mapping applications and software libraries. To support this goal, we will design and develop an OGC-compliant web mapping service prototype providing a specific interface for client applications to search, process, retrieve and visualise the Mars Express/ OMEGA mapping spectrometer data [6] currently available in the PSA. The interface will be designed to accommodate future needs as additional planetary surface data become available or additional functionalities are required. It is anticipated that this web mapping service will provide a practical open framework contributing to the international efforts to define an extension of the PDAP data model for planetary surface data [7][8]. Although it has been demonstrated that OGC web mapping standards can be applied to the planetary science domain, they have limitations that currently prevent the use of their full capability. This study will document such limitations and feed potential recommendations into the Planetary OGC Interoperability Experiment (Planetary IE), an international initiative coordinated by USGS Astrogeology Science Center to ensure that the planetary community will properly leverage future OGC specifications [9].

  4. Computer-assisted photogrammetric mapping systems for geologic studies-A progress report

    USGS Publications Warehouse

    Pillmore, C.L.; Dueholm, K.S.; Jepsen, H.S.; Schuch, C.H.

    1981-01-01

    Photogrammetry has played an important role in geologic mapping for many years; however, only recently have attempts been made to automate mapping functions for geology. Computer-assisted photogrammetric mapping systems for geologic studies have been developed and are currently in use in offices of the Geological Survey of Greenland at Copenhagen, Denmark, and the U.S. Geological Survey at Denver, Colorado. Though differing somewhat, the systems are similar in that they integrate Kern PG-2 photogrammetric plotting instruments and small desk-top computers that are programmed to perform special geologic functions and operate flat-bed plotters by means of specially designed hardware and software. A z-drive capability, in which stepping motors control the z-motions of the PG-2 plotters, is an integral part of both systems. This feature enables the computer to automatically position the floating mark on computer-calculated, previously defined geologic planes, such as contacts or the base of coal beds, throughout the stereoscopic model in order to improve the mapping capabilities of the instrument and to aid in correlation and tracing of geologic units. The common goal is to enhance the capabilities of the PG-2 plotter and provide a means by which geologists can make conventional geologic maps more efficiently and explore ways to apply computer technology to geologic studies. ?? 1981.

  5. A Genomic Approach for Distinguishing between Recent and Ancient Admixture as Applied to Cattle

    PubMed Central

    Hillis, David M.

    2014-01-01

    Genomic data facilitate opportunities to track complex population histories of divergence and gene flow. We developed a metric, scaled block size (SBS), which uses the nonrecombined block size of introgressed regions of chromosomes to differentiate between recent and ancient types of admixture, and applied it to the reconstruction of admixture in cattle. Cattle are descendants of 2 independently domesticated lineages, taurine and indicine, which diverged more than 200 000 years ago. Several breeds have hybrid ancestry between these divergent lineages. Using 47 506 single-nucleotide polymorphisms, we analyzed the genomic architecture of the ancestry of 1369 individuals. We focused on 4 groups with admixed ancestry, including 2 anciently admixed African breeds (n = 58; n = 43), New World cattle of Spanish origin (n = 51), and known recent hybrids (n = 46). We estimated the ancestry of chromosomal regions for each individual and used the SBS metric to differentiate the timing of admixture among groups and among individuals within groups. By comparing SBS values of test individuals with standards with known recent hybrid ancestry, we were able to differentiate individuals of recent hybrid origin from other admixed cattle. We also estimated ancestry at the chromosomal scale. The X chromosome exhibits reduced indicine ancestry in recent hybrid, New World, and western African cattle, with virtually no evidence of indicine ancestry in New World cattle. PMID:24510946

  6. Effects of lithium nitrate admixture on early-age cement hydration

    SciTech Connect

    Millard, M.J. Kurtis, K.E.

    2008-04-15

    Although the benefits of lithium admixtures for mitigation of alkali-silica reaction (ASR) have been well documented, the potential ancillary effects of lithium compounds on cement and concrete remain largely uncharacterized. To examine the effects of the most common lithium admixture - lithium nitrate - on early-age behavior, the admixture was introduced at dosages of 0% to 400% of the recommended dosage to six cements of varying composition and to a cement-fly ash blend. Behavior was examined by isothermal calorimetry and measurements of chemical shrinkage, autogenous shrinkage, and setting time. Results indicate that lithium nitrate accelerates the early hydration of most cements but may retard hydration after 24 h. In the lowest alkali cement tested, set times were shortened in the presence of lithium nitrate by 15-22%. Higher dosages appeared to increase autogenous shrinkage after 40 days. The replacement of cement by Class F fly ash at 20% by weight appeared to diminish the early acceleration effects, but later hydration retardation and autogenous shrinkage were still observed.

  7. Including non-public data and studies in systematic reviews and systematic maps.

    PubMed

    Haddaway, Neal R; Collins, Alexandra M; Coughlin, Deborah; Kohl, Christian

    2017-02-01

    Systematic reviews and maps should be based on the best available evidence, and reviewers should make all reasonable efforts to source and include potentially relevant studies. However, reviewers may not be able to consider all existing evidence, since some data and studies may not be publicly available. Including non-public studies in reviews provides a valuable opportunity to increase systematic review/map comprehensiveness, potentially mitigating negative impacts of publication bias. Studies may be non-public for many reasons: some may still be in the process of being published (publication can take a long time); some may not be published due to author/publisher restrictions; publication bias may make it difficult to publish non-significant or negative results. Here, we consider what forms these non-public studies may take and the implications of including them in systematic reviews and maps. Reviewers should carefully consider the advantages and disadvantages of including non-public studies, weighing risks of bias against benefits of increased comprehensiveness. As with all systematic reviews and maps, reviewers must be transparent about methods used to obtain data and avoid risks of bias in their synthesis. We make tentative suggestions for reviewers in situations where non-public data may be present in an evidence base.

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

    PubMed

    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.

  9. Development and Experimental Study of Phantoms for Mapping Skin Chromophores

    NASA Astrophysics Data System (ADS)

    Silapetere, A.; Spigulis, J.; Saknite, I.

    2014-06-01

    Skin chromophore phantoms are widely used for better understanding of the light interaction with tissue and for calibration of skin diagnostic imaging techniques. In this work, different phantoms were examined and compared in order to find biologically equivalent substances that are the most promising for this purpose. For mimicking the skin medium and layered structure, a fibrin matrix with epidermal and dermal cell inclusion was used. Synthesized bilirubin, red blood cells and nigrosin were taken as absorbers. For spectral analysis of the developed phantoms a computer-aided multispectral imaging system Nuance 2.4 (Cambridge Research & Instrumentation, Inc., USA) was used. In this study, skin phantoms were created using such substances as bilirubin, melanin, haemoglobin and nigrosin Mūsdienās multispektrālās attēlošanas iekārtas izmanto ādas parametru un fizioloģisko procesu aprakstīšanai gan pētniecības, gan diagnostikas nolūkiem. Iekārtu darbības uzlabošanai ir nepieciešams labāk saprast gaismas mijiedarbību ar audiem, kā arī veikt šo iekārtu kalibrēšanu ar ādas maketu. Redzamā un tuvā infrasarkanā optiskā diapazona spektroskopijā ir svarīgi ādas maketi, kas simulē audu slāņaino struktūru un ķīmiskās īpašības, kā arī maketi, kas ir bioloģiski līdzvērtīgi. Šajā pētījumā tika izveidots ādas makets no bioloģiskām un ķīmiski sintezētām struktūrām. Ādas maketa izveidei tika izmantota fibrīna matrica ar dermālo un epidermālo šūnu piejaukumu, lai imitētu ādas slāņaino struktūru. Fibrīna matrica tiek veidota no 0,47 ml asins plazmas, 0,4 ml fizioloģiskā šķīduma, 0,8 μl treneksāmskābes un 89,4 μl kalcija glukanāta. Izveidoto matricu ievieto šūnu inkubatorā, lai tā polimerizētos. Nākošais slānis tiek veidots ar dermālo šūnu piejaukumu (180-270 šūnas), un pēdējais fibrīna matriksa slānis tiek veidots ar epidermālo šūnu piejaukumu (270 šūnas) un šūnu aug

  10. Seaside, Oregon, Tsunami Pilot Study-Modernization of FEMA Flood Hazard Maps: GIS Data

    USGS Publications Warehouse

    Wong, Florence L.; Venturato, Angie J.; Geist, Eric L.

    2006-01-01

    Introduction: The Federal Emergency Management Agency (FEMA) Federal Insurance Rate Map (FIRM) guidelines do not currently exist for conducting and incorporating tsunami hazard assessments that reflect the substantial advances in tsunami research achieved in the last two decades; this conclusion is the result of two FEMA-sponsored workshops and the associated Tsunami Focused Study (Chowdhury and others, 2005). Therefore, as part of FEMA's Map Modernization Program, a Tsunami Pilot Study was carried out in the Seaside/Gearhart, Oregon, area to develop an improved Probabilistic Tsunami Hazard Analysis (PTHA) methodology and to provide recommendations for improved tsunami hazard assessment guidelines (Tsunami Pilot Study Working Group, 2006). The Seaside area was chosen because it is typical of many coastal communities in the section of the Pacific Coast from Cape Mendocino to the Strait of Juan de Fuca, and because State agencies and local stakeholders expressed considerable interest in mapping the tsunami threat to this area. The study was an interagency effort by FEMA, U.S. Geological Survey, and the National Oceanic and Atmospheric Administration (NOAA), in collaboration with the University of Southern California, Middle East Technical University, Portland State University, Horning Geoscience, Northwest Hydraulics Consultants, and the Oregon Department of Geological and Mineral Industries. We present the spatial (geographic information system, GIS) data from the pilot study in standard GIS formats and provide files for visualization in Google Earth, a global map viewer.

  11. Development of PowerMap: a software package for statistical power calculation in neuroimaging studies.

    PubMed

    Joyce, Karen E; Hayasaka, Satoru

    2012-10-01

    Although there are a number of statistical software tools for voxel-based massively univariate analysis of neuroimaging data, such as fMRI (functional MRI), PET (positron emission tomography), and VBM (voxel-based morphometry), very few software tools exist for power and sample size calculation for neuroimaging studies. Unlike typical biomedical studies, outcomes from neuroimaging studies are 3D images of correlated voxels, requiring a correction for massive multiple comparisons. Thus, a specialized power calculation tool is needed for planning neuroimaging studies. To facilitate this process, we developed a software tool specifically designed for neuroimaging data. The software tool, called PowerMap, implements theoretical power calculation algorithms based on non-central random field theory. It can also calculate power for statistical analyses with FDR (false discovery rate) corrections. This GUI (graphical user interface)-based tool enables neuroimaging researchers without advanced knowledge in imaging statistics to calculate power and sample size in the form of 3D images. In this paper, we provide an overview of the statistical framework behind the PowerMap tool. Three worked examples are also provided, a regression analysis, an ANOVA (analysis of variance), and a two-sample T-test, in order to demonstrate the study planning process with PowerMap. We envision that PowerMap will be a great aide for future neuroimaging research.

  12. A study of lidar-based sense making and topographic mapping

    NASA Astrophysics Data System (ADS)

    Wu, Qinghua; Lu, Yilong

    2012-11-01

    The paper presents a study of topographic mapping and sense making with LIDAR data and ground color map. The objective is for possible alternative navigation in case the GPS service is not available. To achieve the objective, a few LIDAR data filtering and image processing techniques are applied. From LIDAR data, an accurate digital elevation model is first generated, then a progressive morphological filtering to remove such interference objects as trees for more reliable matching afterwards. For topographic mapping, the processed LIDAR image and a ground map image are segmented based on the Mean-Shift principle, segmenting the image into different color blocks, then extracting the building color blocks and converting into binary image. Lastly based on the least sum of absolute value, we are able to matching a LIDAR image with a real map image. By performing the effective image filtering and matching process, we have successfully achieved accurate topographic matching based on real LIDAR measurement taken in Singapore. This automatic processing is able to indicate exactly where the LIDAR image was taken.

  13. Mapping nouns and finite verbs in left hemisphere tumors: a direct electrical stimulation study.

    PubMed

    Rofes, Adrià; Spena, Giannantonio; Talacchi, Andrea; Santini, Barbara; Miozzo, Antonio; Miceli, Gabriele

    2017-03-27

    Neurosurgical mapping studies with nouns and finite verbs are scarce and subcortical data are nonexistent. We used a new task that uses finite verbs in six Italian-speaking patients with gliomas in the left language-dominant hemisphere. Language-relevant positive areas were detected only with nouns in four patients, with both tasks yet in distinct cortical areas in one patient, and only with finite verbs in another patient. Positive areas and types of errors varied across participants. Finite verbs provide complementary information to nouns, and permit more accurate mapping of language production when nouns are unaffected by electrical stimulation.

  14. Studies of phase return map and symbolic dynamics in a periodically driven Hodgkin—Huxley neuron

    NASA Astrophysics Data System (ADS)

    Ding, Jiong; Zhang, Hong; Tong, Qin-Ye; Chen, Zhuo

    2014-02-01

    How neuronal spike trains encode external information is a hot topic in neurodynamics studies. In this paper, we investigate the dynamical states of the Hodgkin—Huxley neuron under periodic forcing. Depending on the parameters of the stimulus, the neuron exhibits periodic, quasiperiodic and chaotic spike trains. In order to analyze these spike trains quantitatively, we use the phase return map to describe the dynamical behavior on a one-dimensional (1D) map. According to the monotonicity or discontinuous point of the 1D map, the spike trains are transformed into symbolic sequences by implementing a coarse-grained algorithm — symbolic dynamics. Based on the ordering rules of symbolic dynamics, the parameters of the external stimulus can be measured in high resolution with finite length symbolic sequences. A reasonable explanation for why the nervous system can discriminate or cognize the small change of the external signals in a short time is also presented.

  15. The Study of Insurance Premium Rate GIS Mapping Considering the Storm and Flood Hazard Risks

    NASA Astrophysics Data System (ADS)

    Lee, J. S.; Lee, I. S.

    2016-06-01

    Recently, the number of natural disaster occurrence is increasing because of abnormal changes of weather in Korea. In Korea the storm and flood insurance system is in effect to prevent these natural disasters. The national storm and flood insurance Premium rate is very low and the risk of adverse selection resides because of choosing by who lives in high risk area. To solve these problems, the storm and flood insurance rate map are required. In this study, the prototype of storm and flood insurance premium rate map of the Ulsan, Korea was made and the method of GIS analysis for the insurance premium rate calculating and the procedure of the Ulsan storm and flood insurance rate map were researched.

  16. The Effect of Using Concept Maps as Study Tools on Achievement in Chemistry

    ERIC Educational Resources Information Center

    BouJaoude, Saouma; Attieh, May

    2008-01-01

    The purposes of this study were to: (1) examine whether or not the construction of concept maps by students improves their achievement and ability to solve higher order questions in chemistry, (2) investigate the differential effect of the treatment by gender and achievement level, and (3) explore the relationships between performance on concept…

  17. A Study of Kindergarten Children's Spatial Representation in a Mapping Project

    ERIC Educational Resources Information Center

    Davis, Genevieve A.; Hyun, Eunsook

    2005-01-01

    This phenomenological study examined kindergarten children's development of spatial representation in a year long mapping project. Findings and discussion relative to how children conceptualised and represented physical space are presented in light of theoretical notions advanced by Piaget, van Hiele, and cognitive science researchers Battista and…

  18. A Hundred and One Satellite Map Bargains for Social Studies Teachers.

    ERIC Educational Resources Information Center

    Kirman, Joseph M.

    1981-01-01

    Recommends that social studies classroom teachers use landsat images in geography units to teach students about map interpretation. Information is presented on interpreting landsat images, uses of landsat images in the classroom, cities for which landsat images are available, and ordering information. (DB)

  19. How Do High-School Students Perceive the Concept of "Map": A Case Study from Istanbul

    ERIC Educational Resources Information Center

    Ozder, Adem

    2013-01-01

    The main aim of this study is investigating metaphors developed by the students regarding the concept of "map" at private institutions which provide them with specialized courses (Dershane). About 338 students in one of these private courses in Istanbul city center accepted to participate in the research within 2012 to 2013 academic…

  20. Combining Mapping and Citation Analysis for Evaluative Bibliometric Purposes: A Bibliometric Study.

    ERIC Educational Resources Information Center

    Noyons, E. C. M; Moed, H. F.; Luwel, M.

    1999-01-01

    Presents the results of a combined performance/mapping study used to evaluate a Belgian research institute in microelectronics. Results from one bibliometric approach were used to validate results of another. Findings indicated that the method provides a detailed and useful picture of the position of the institute from an international…

  1. Utilization of Historical Maps in the Land Use Change Impact Studies: A Case Study from Myjava River Basin

    NASA Astrophysics Data System (ADS)

    Valent, P.; Rončák, P.; Maliariková, M.; Behan, Š.

    2016-12-01

    The way land is used has a significant impact on many hydrological processes that determine the generation of flood runoff or soil erosion. Advancements in remote sensing which took place in the second half of the 20th century have led to the rise of a new research area focused on analyses of land use changes and their impact on hydrological processes. This study deals with an analysis of the changes in land use over a period of almost three centuries in the Myjava River catchment, which has an outlet at Šaštín-Stráže. In order to obtain information about the way the land was used in the past, three historical mappings representing various periods were used: the first (1st) military mapping (1764-1787), second (2nd) military mapping (1807-1869), and a military topographic mapping (1953-1957). The historical mappings have been manually vectorised in an ArcGIS environment to identify various land use categories. The historical evolution of land use was further compared with a concurrent land use mapping, which was undertaken in 2010 and exploited remote sensing techniques. The study also quantifies the impact of these changes on the long-term catchment runoff as well as their impact on flows induced by extreme precipitation events. This analysis was performed using the WetSpa distributed hydrological model, which enables the simulation of catchment runoff in a daily time step. The analysis showed that the selected catchment has undergone significant changes in land use, mainly characterized by massive deforestation at the end of the 18th century and land consolidation in the middle of the 20th century induced by communist collectivisation. The hydrological simulations demonstrated that the highest and lowest mean annual runoffs were simulated in the first (1st military mapping) and the last (concurrent land use monitoring) time intervals respectively with the smallest and largest percentages of forested areas.

  2. Disease mapping and risk assessment in veterinary parasitology: some case studies.

    PubMed

    Cringoli, G; Rinaldi, L; Veneziano, V; Musella, V

    2005-03-01

    Disease mapping and risk assessment are important tasks in the area of medical and veterinary epidemiology. The development of methods for mapping diseases has progressed considerably in recent years. Geographical Information Systems (GIS), Remote Sensing (RS), and Spatial Analysis represent new tools for the study of epidemiology, and their application to parasitology has become more and more advanced, in particular to study the spatial and temporal patterns of diseases. The present review highlights the usefulness of GIS and RS in veterinary parasitology in order to better know the epidemiology of parasite organisms, causing either snail/arthropod borne diseases or direct transmissible diseases, mostly in small areas with a strong impact by man. It demonstrates the potential of these technologies to serve as effective tools for: data capture, mapping and analysis for the development of descriptive parasitological maps; studying the environmental features that influence the distribution of parasites; predicting parasite occurrence/seasonality based on their environmental requirements and as decision support for disease intervention; and surveillance and monitoring of animal diseases.

  3. 78 FR 71707 - MAP-21 Comprehensive Truck Size and Weight Limits Study Public Meeting and Outreach Sessions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-29

    ... Federal Highway Administration MAP-21 Comprehensive Truck Size and Weight Limits Study Public Meeting and... Century Act (MAP-21) Comprehensive Truck Size and Weight Limits Study. The Transportation Research Board Committee for Review of the U.S. Department of Transportation (DOT) Truck Size and Weight Limits Study...

  4. Important considerations in lesion-symptom mapping: Illustrations from studies of word comprehension.

    PubMed

    Shahid, Hinna; Sebastian, Rajani; Schnur, Tatiana T; Hanayik, Taylor; Wright, Amy; Tippett, Donna C; Fridriksson, Julius; Rorden, Chris; Hillis, Argye E

    2017-03-20

    Lesion-symptom mapping is an important method of identifying networks of brain regions critical for functions. However, results might be influenced substantially by the imaging modality and timing of assessment. We tested the hypothesis that brain regions found to be associated with acute language deficits depend on (1) timing of behavioral measurement, (2) imaging sequences utilized to define the "lesion" (structural abnormality only or structural plus perfusion abnormality), and (3) power of the study. We studied 191 individuals with acute left hemisphere stroke with MRI and language testing to identify areas critical for spoken word comprehension. We use the data from this study to examine the potential impact of these three variables on lesion-symptom mapping. We found that only the combination of structural and perfusion imaging within 48 h of onset identified areas where more abnormal voxels was associated with more severe acute deficits, after controlling for lesion volume and multiple comparisons. The critical area identified with this methodology was the left posterior superior temporal gyrus, consistent with other methods that have identified an important role of this area in spoken word comprehension. Results have implications for interpretation of other lesion-symptom mapping studies, as well as for understanding areas critical for auditory word comprehension in the healthy brain. We propose that lesion-symptom mapping at the acute stage of stroke addresses a different sort of question about brain-behavior relationships than lesion-symptom mapping at the chronic stage, but that timing of behavioral measurement and imaging modalities should be considered in either case. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

  5. The Design and Use of an Optical Mapping System for the Study of Intracardiac Electrical Signaling

    PubMed Central

    Shrivastav, Maneesh; Ghai, Megan B; Singal, Ashish; Iaizzo, Paul A

    2012-01-01

    Fluorescent optical mapping of electrically active cardiac tissues provides a unique method to examine the excitation wave dynamics of underlying action potentials. Such mapping can be viewed as a bridge between cellular level and organ systems physiology, e.g., by facilitating the development of advanced theoretical concepts of arrhythmia. We present the design and use of a high-speed, high-resolution optical mapping system composed entirely of "off the shelf" components. The electrical design integrates a 256 element photodiode array with a 16 bit data acquisition system. Proper grounding and shielding at various stages of the design reduce electromagnetic interference. Our mechanical design provides flexibility in terms of mounting positions and applications (use for whole heart or tissue preparations), while maintaining precise alignment between all optical components. The system software incorporates a user friendly graphical user interface, e.g., spatially recorded action potentials can be represented as intensity graphs or in strip chart format. Thus, this system is capable of displaying cardiac action potentials with high spatiotemporal resolution. Results from cardiac action potential mapping with intact mouse hearts are provided. It should be noted that this system could be readily configured to study isolated myocardial biopsies (e.g., isolated ventricular trabeculae). We describe the details of a versatile, user-friendly system that could be employed for a magnitude of study protocols. PMID:22912535

  6. Mineral resource potential map of the Muddy Mountains Wilderness Study Area, Clark County, Nevada

    USGS Publications Warehouse

    Bohannon, Robert G.; Leszcykowski, Andrew M.; Esparza, Leon E.; Rumsey, Clayton M.

    1982-01-01

    The Muddy Mountains Wilderness Study Area (WSA 050-0229), Clark County, Nevada, has a high potential for mineral deposits of calcium borates and lithium. The known and potential mineral deposits are concentrated in the east-central and south-central parts of the study area (see map). Zeolites (in particular clinoptilolite) are present in some tuff beds throughout much of the study area, and this resource potential is probably moderate to high. Stream-sediment sampling suggests that the Muddy Mountains area has little potential for mineral deposits of metals (other than lithium). Clay minerals are mined at one locality in the (!rea (see map). Building stone and silica sand have moderate to low potential in some places. Oil and gas potential within the study area is low, but complete evaluation of its potential is not possible without drilling.

  7. Two-locus admixture linkage analysis of bipolar and unipolar affective disorder supports the presence of susceptibility loci on chromosomes 11p15 and 21q22

    SciTech Connect

    Smyth, C.; Kalsi, G.; O`Neill, J.

    1997-02-01

    Following a report of a linkage study that yielded evidence for a susceptibility locus for bipolar affective disorder on the long arm of chromosome 21, we studied 23 multiply affected pedigrees collected from Iceland and the UK, using the markers PFKL, D21S171, and D21S49. Counting only bipolar cases as affected, a two-point LOD of 1.28 was obtained using D21S171 ({theta} = 0.01, {alpha} = 0.35), with three Icelandic families producing LODs of 0.63, 0.62, and 1.74 (all at {theta} = 0.0). Affected sib pair analysis demonstrated increased allele sharing at D21S171 (P = 0.001) when unipolar cases were also considered affected. The same set of pedigrees had previously been typed for a tyrosine hydroxylase gene (TH) polymorphism at 11p15 and had shown some moderate evidence for linkage. When information from TH and the 21q markers was combined in a two-locus admixture analysis, an overall admixture LOD of 3.87 was obtained using the bipolar affection model. Thus the data are compatible with the hypothesis that a locus at or near TH influences susceptibility in some pedigrees, while a locus near D21S171 is active in others. Similar analyses in other datasets should be carried out to confirm or refute our tentative finding. 66 refs., 3 tabs.

  8. Growth, structural, spectral, mechanical, thermal and dielectric characterization of phosphoric acid admixtured L-alanine (PLA) single crystals

    NASA Astrophysics Data System (ADS)

    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.

  9. Growth, structural, spectral, mechanical, thermal and dielectric characterization of phosphoric acid admixtured L-alanine (PLA) single crystals.

    PubMed

    Rose, A S J Lucia; Selvarajan, P; Perumal, S

    2011-10-15

    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.

  10. Fast IR laser mapping ellipsometry for the study of functional organic thin films.

    PubMed

    Furchner, Andreas; Sun, Guoguang; Ketelsen, Helge; Rappich, Jörg; Hinrichs, Karsten

    2015-03-21

    Fast infrared mapping with sub-millimeter lateral resolution as well as time-resolved infrared studies of kinetic processes of functional organic thin films require a new generation of infrared ellipsometers. We present a novel laboratory-based infrared (IR) laser mapping ellipsometer, in which a laser is coupled to a variable-angle rotating analyzer ellipsometer. Compared to conventional Fourier-transform infrared (FT-IR) ellipsometers, the IR laser ellipsometer provides ten- to hundredfold shorter measurement times down to 80 ms per measured spot, as well as about tenfold increased lateral resolution of 120 μm, thus enabling mapping of small sample areas with thin-film sensitivity. The ellipsometer, equipped with a HeNe laser emitting at about 2949 cm(-1), was applied for the optical characterization of inhomogeneous poly(3-hexylthiophene) [P3HT] and poly(N-isopropylacrylamide) [PNIPAAm] organic thin films used for opto-electronics and bioapplications. With the constant development of tunable IR laser sources, laser-based infrared ellipsometry is a promising technique for fast in-depth mapping characterization of thin films and blends.

  11. Linkage disequilibrium fine mapping of quantitative trait loci: A simulation study

    PubMed Central

    Abdallah, Jihad M; Goffinet, Bruno; Cierco-Ayrolles, Christine; Pérez-Enciso, Miguel

    2003-01-01

    Recently, the use of linkage disequilibrium (LD) to locate genes which affect quantitative traits (QTL) has received an increasing interest, but the plausibility of fine mapping using linkage disequilibrium techniques for QTL has not been well studied. The main objectives of this work were to (1) measure the extent and pattern of LD between a putative QTL and nearby markers in finite populations and (2) investigate the usefulness of LD in fine mapping QTL in simulated populations using a dense map of multiallelic or biallelic marker loci. The test of association between a marker and QTL and the power of the test were calculated based on single-marker regression analysis. The results show the presence of substantial linkage disequilibrium with closely linked marker loci after 100 to 200 generations of random mating. Although the power to test the association with a frequent QTL of large effect was satisfactory, the power was low for the QTL with a small effect and/or low frequency. More powerful, multi-locus methods may be required to map low frequent QTL with small genetic effects, as well as combining both linkage and linkage disequilibrium information. The results also showed that multiallelic markers are more useful than biallelic markers to detect linkage disequilibrium and association at an equal distance. PMID:12939203

  12. Investigating word learning in fragile X syndrome: a fast-mapping study.

    PubMed

    McDuffie, Andrea; Kover, Sara T; Hagerman, Randi; Abbeduto, Leonard

    2013-07-01

    Fast-mapping paradigms have not been used previously to examine the process of word learning in boys with fragile X syndrome (FXS), who are likely to have intellectual impairment, language delays, and symptoms of autism. In this study, a fast-mapping task was used to investigate associative word learning in 4- to 10-year-old boys with FXS relative to younger typically developing boys and age-matched boys with autism spectrum disorders (ASD). Task performance exceeded chance levels for all groups; however, boys with FXS outperformed boys with ASD, despite having lower levels of nonverbal cognition. Memory task demands significantly impacted performance only for boys with typical development. For boys with FXS or ASD, fast-mapping uniquely accounted for small but significant variance in concurrent levels of vocabulary comprehension as did chronological age and nonverbal IQ, but not autism severity. Understanding the fast-mapping process has implications for designing interventions to support word learning and language acquisition in these populations.

  13. GIS data for the Seaside, Oregon, Tsunami Pilot Study to modernize FEMA flood hazard maps

    USGS Publications Warehouse

    Wong, Florence L.; Venturato, Angie J.; Geist, Eric L.

    2007-01-01

    A Tsunami Pilot Study was conducted for the area surrounding the coastal town of Seaside, Oregon, as part of the Federal Emergency Management's (FEMA) Flood Insurance Rate Map Modernization Program (Tsunami Pilot Study Working Group, 2006). The Cascadia subduction zone extends from Cape Mendocino, California, to Vancouver Island, Canada. The Seaside area was chosen because it is typical of many coastal communities subject to tsunamis generated by far- and near-field (Cascadia) earthquakes. Two goals of the pilot study were to develop probabilistic 100-year and 500-year tsunami inundation maps using Probabilistic Tsunami Hazard Analysis (PTHA) and to provide recommendations for improving tsunami hazard assessment guidelines for FEMA and state and local agencies. The study was an interagency effort by the National Oceanic and Atmospheric Administration, U.S. Geological Survey, and FEMA, in collaboration with the University of Southern California, Middle East Technical University, Portland State University, Horning Geoscience, Northwest Hydraulics Consultants, and the Oregon Department of Geological and Mineral Industries. The pilot study model data and results are published separately as a geographic information systems (GIS) data report (Wong and others, 2006). The flood maps and GIS data are briefly described here.

  14. Independent introductions and admixtures have contributed to adaptation of European maize and its American counterparts

    PubMed Central

    Brandenburg, Jean-Tristan; Mary-Huard, Tristan; Rigaill, Guillem; Corti, Hélène; Vitte, Clémentine; Charcosset, Alain; Tenaillon, Maud I.

    2017-01-01

    Through the local selection of landraces, humans have guided the adaptation of crops to a vast range of climatic and ecological conditions. This is particularly true of maize, which was domesticated in a restricted area of Mexico but now displays one of the broadest cultivated ranges worldwide. Here, we sequenced 67 genomes with an average sequencing depth of 18x to document routes of introduction, admixture and selective history of European maize and its American counterparts. To avoid the confounding effects of recent breeding, we targeted germplasm (lines) directly derived from landraces. Among our lines, we discovered 22,294,769 SNPs and between 0.9% to 4.1% residual heterozygosity. Using a segmentation method, we identified 6,978 segments of unexpectedly high rate of heterozygosity. These segments point to genes potentially involved in inbreeding depression, and to a lesser extent to the presence of structural variants. Genetic structuring and inferences of historical splits revealed 5 genetic groups and two independent European introductions, with modest bottleneck signatures. Our results further revealed admixtures between distinct sources that have contributed to the establishment of 3 groups at intermediate latitudes in North America and Europe. We combined differentiation- and diversity-based statistics to identify both genes and gene networks displaying strong signals of selection. These include genes/gene networks involved in flowering time, drought and cold tolerance, plant defense and starch properties. Overall, our results provide novel insights into the evolutionary history of European maize and highlight a major role of admixture in environmental adaptation, paralleling recent findings in humans. PMID:28301472

  15. Independent introductions and admixtures have contributed to adaptation of European maize and its American counterparts.

    PubMed

    Brandenburg, Jean-Tristan; Mary-Huard, Tristan; Rigaill, Guillem; Hearne, Sarah J; Corti, Hélène; Joets, Johann; Vitte, Clémentine; Charcosset, Alain; Nicolas, Stéphane D; Tenaillon, Maud I

    2017-03-01

    Through the local selection of landraces, humans have guided the adaptation of crops to a vast range of climatic and ecological conditions. This is particularly true of maize, which was domesticated in a restricted area of Mexico but now displays one of the broadest cultivated ranges worldwide. Here, we sequenced 67 genomes with an average sequencing depth of 18x to document routes of introduction, admixture and selective history of European maize and its American counterparts. To avoid the confounding effects of recent breeding, we targeted germplasm (lines) directly derived from landraces. Among our lines, we discovered 22,294,769 SNPs and between 0.9% to 4.1% residual heterozygosity. Using a segmentation method, we identified 6,978 segments of unexpectedly high rate of heterozygosity. These segments point to genes potentially involved in inbreeding depression, and to a lesser extent to the presence of structural variants. Genetic structuring and inferences of historical splits revealed 5 genetic groups and two independent European introductions, with modest bottleneck signatures. Our results further revealed admixtures between distinct sources that have contributed to the establishment of 3 groups at intermediate latitudes in North America and Europe. We combined differentiation- and diversity-based statistics to identify both genes and gene networks displaying strong signals of selection. These include genes/gene networks involved in flowering time, drought and cold tolerance, plant defense and starch properties. Overall, our results provide novel insights into the evolutionary history of European maize and highlight a major role of admixture in environmental adaptation, paralleling recent findings in humans.

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

    PubMed

    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; Montiel, Rafael; Bachmann, Lutz; Ingólfsson, Olafur; Aars, Jon; Mailund, Thomas; Wiig, Oystein; Talbot, Sandra L; Lindqvist, Charlotte

    2012-09-04

    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.

  17. The Effects of Migration and Assortative Mating on Admixture Linkage Disequilibrium.

    PubMed

    Zaitlen, Noah; Huntsman, Scott; Hu, Donglei; Spear, Melissa; Eng, Celeste; Oh, Sam S; White, Marquitta J; Mak, Angel; Davis, Adam; Meade, Kelly; Brigino-Buenaventura, Emerita; LeNoir, Michael A; Bibbins-Domingo, Kirsten; Burchard, Esteban G; Halperin, Eran

    2017-01-01

    Statistical models in medical and population genetics typically assume that individuals assort randomly in a population. While this simplifies model complexity, it contradicts an increasing body of evidence of nonrandom mating in human populations. Specifically, it has been shown that assortative mating is significantly affected by genomic ancestry. In this work, we examine the effects of ancestry-assortative mating on the linkage disequilibrium between local ancestry tracks of individuals in an admixed population. To accomplish this, we develop an extension to the Wright-Fisher model that allows for ancestry-based assortative mating. We show that ancestry-assortment perturbs the distribution of local ancestry linkage disequilibrium (LAD) and the variance of ancestry in a population as a function of the number of generations since admixture. This assortment effect can induce errors in demographic inference of admixed populations when methods assume random mating. We derive closed form formulae for LAD under an assortative-mating model with and without migration. We observe that LAD depends on the correlation of global ancestry of couples in each generation, the migration rate of each of the ancestral populations, the initial proportions of ancestral populations, and the number of generations since admixture. We also present the first direct evidence of ancestry-assortment in African Americans and examine LAD in simulated and real admixed population data of African Americans. We find that demographic inference under the assumption of random mating significantly underestimates the number of generations since admixture, and that accounting for assortative mating using the patterns of LAD results in estimates that more closely agrees with the historical narrative.

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

    USGS Publications Warehouse

    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. Admixture and local breed marginalization threaten Algerian sheep diversity.

    PubMed

    Gaouar, Samir Bachir Souheil; Da Silva, Anne; Ciani, Elena; Kdidi, Samia; Aouissat, Miloud; Dhimi, Laziz; Lafri, Mohamed; Maftah, Abderrahman; Mehtar, Nadhira

    2015-01-01

    Due to its geo-climatic conditions, Algeria represents a biodiversity hotspot, with sheep breeds well adapted to a patchwork of extremely heterogeneous harsh habitats. The importance of this peculiar genetic reservoir increases as climate change drives the demand for new adaptations. However, the expansion of a single breed (Ouled-Djellal) which occurred in the last decades has generated a critical situation for the other breeds; some of them are being subjected to uncontrolled cross-breeding with the favored breed and/or to marginalization (effective size contraction). This study investigated genetic diversity within and among six of the nine Algerian breeds, by use of 30 microsatellite markers. Our results showed that, in spite of the census contraction experienced by most of the considered breeds, genetic diversity is still substantial (average gene diversity ranging 0.68 to 0.76) and inbreeding was not identified as a problem. However, two breeds (Rembi and Taâdmit) appeared to have lost most of their genetic originality because of intensive cross-breeding with Ouled-Djellal. Based on the above evidence, we suggest Hamra, Sidaoun, and D'man as breeds deserving the highest priority for conservation in Algeria.

  20. Admixture and Local Breed Marginalization Threaten Algerian Sheep Diversity

    PubMed Central

    Ciani, Elena; Kdidi, Samia; Aouissat, Miloud; Dhimi, Laziz; Lafri, Mohamed; Maftah, Abderrahman; Mehtar, Nadhira

    2015-01-01

    Due to its geo-climatic conditions, Algeria represents a biodiversity hotspot, with sheep breeds well adapted to a patchwork of extremely heterogeneous harsh habitats. The importance of this peculiar genetic reservoir increases as climate change drives the demand for new adaptations. However, the expansion of a single breed (Ouled-Djellal) which occurred in the last decades has generated a critical situation for the other breeds; some of them are being subjected to uncontrolled cross-breeding with the favored breed and/or to marginalization (effective size contraction). This study investigated genetic diversity within and among six of the nine Algerian breeds, by use of 30 microsatellite markers. Our results showed that, in spite of the census contraction experienced by most of the considered breeds, genetic diversity is still substantial (average gene diversity ranging 0.68 to 0.76) and inbreeding was not identified as a problem. However, two breeds (Rembi and Taâdmit) appeared to have lost most of their genetic originality because of intensive cross-breeding with Ouled-Djellal. Based on the above evidence, we suggest Hamra, Sidaoun, and D’man as breeds deserving the highest priority for conservation in Algeria. PMID:25875832

  1. A Simple Analytical Approximation to an Inhomogeneously-Broadened Dispersion Spectrum. Application to Absorption-Dispersion Admixtures.

    PubMed

    Bales, Barney L

    2016-09-19

    A simple analytical approximation to an inhomogeneously-broadened dispersion signal is proposed and tested with resonance lines broadened by unresolved hyperfine structure. Spectral parameters may be rapidly and accurately extracted using a nonlinear least-squares fitting algorithm. Combining the new approximation to a dispersion signal with a well-known approximation to the absorption signal allows dispersion-absorption admixtures, a problem of growing importance, to be analyzed quickly and accurately. For pure dispersion signals, the maximum difference between the fit and the signal for unresolved lines is 1.1 % of the maximum intensity. For pure absorption, the difference is 0.33 % of the peak-to-peak intensity, and for admixtures up to 40 % dispersion (maximum intensity/peak-to-peak intensity), the difference is 0.7 %. The accuracy of the recovered spectral parameters depends on the degree of inhomogeneously-broadened and the percentage admixture, but they are generally about 1 % at most. A significant finding of the work is that the parameters pertinent to the dispersion or the absorption are insignificantly different when fitting isolated lines vs. fitting admixtures. Admixtures with added noise or an unsuspected extraneous line are investigated.

  2. The Effectiveness of Panoramic Maps Design: a Preliminary Study Based on Mobile Eye-Tracking

    NASA Astrophysics Data System (ADS)

    Balzarini, R.; Murat, M.

    2016-06-01

    This paper presents preliminary results from an ongoing research based on the study of visual attention through mobile eye-tracking techniques. The visual-cognitive approach investigates the reading-comprehension of a particular territorial representation: ski trails maps. The general issue of the study is to provide insights about the effectiveness of panoramic ski maps and more broadly, to suggest innovative efficient representation of the geographic information in mountain. According to some mountain operators, the information provided by paper ski maps no longer meets the needs of a large part of the customers; the question now arises of their adaptation to new digital practices (iPhone, tablets). In a computerized process perspective, this study particularly focuses on the representations, and the inferred information, which are really helpful to the users-skiers to apprehend the territory and make decisions, and which could be effectively replicated into a digital system. The most interesting output relies on the relevance of the panorama view: panorama still fascinates, but contrary to conventional wisdom, the information it provides does not seem to be useful to the skier. From a socio-historical perspective this study shows how empirical evidence-based approach can support the change: our results enhance the discussion on the effectiveness of the message that mountain operators want to convey to the tourist and therefore, on the renewal of (geographical) information in ski resorts.

  3. Admixture of Eastern and Western European Red Deer Lineages as a Result of Postglacial Recolonization of the Czech Republic (Central Europe).

    PubMed

    Krojerová-Prokešová, Jarmila; Barančeková, Miroslava; Koubek, Petr

    2015-01-01

    Due to a restriction of the distributional range of European red deer (Cervus elaphus L.) during the Quaternary and subsequent recolonization of Europe from different refugia, a clear phylogeographical pattern in genetic structure has been revealed using mitochondrial DNA markers. In Central Europe, 2 distinct, eastern and western, lineages of European red deer are present; however, admixture between them has not yet been studied in detail. We used mitochondrial DNA (control region and cytochrome b gene) sequences and 22 microsatellite loci from 522 individuals to investigate the genetic diversity of red deer in what might be expected to be an intermediate zone. We discovered a high number of unique mtDNA haplotypes belonging to each lineage and high levels of genetic diversity (cyt b H = 0.867, D-loop H = 0.914). The same structuring of red deer populations was also revealed by microsatellite analysis, with results from both analyses thus suggesting a suture zone between the 2 lineages. Despite the fact that postglacial recolonization of Central Europe by red deer occurred more than 10000 years ago, the degree of admixture between the 2 lineages is relatively small, with only 10.8% admixed individuals detected. Direct translocations of animals by humans have slightly blurred the pattern in this region; however, this blurring was more apparent when using maternally inherited markers than nuclear markers.

  4. Generating an agricultural risk map based on limited ecological information: A case study using Sicyos angulatus.

    PubMed

    Osawa, Takeshi; Okawa, Shigenori; Kurokawa, Shunji; Ando, Shinichiro

    2016-12-01

    In this study, we propose a method for estimating the risk of agricultural damage caused by an invasive species when species-specific information is lacking. We defined the "risk" as the product of the invasion probability and the area of potentially damaged crop for production. As a case study, we estimated the risk imposed by an invasive weed, Sicyos angulatus, based on simple cellular simulations and governmental data on the area of crop that could potentially be damaged in Miyagi Prefecture, Japan. Simulation results revealed that the current distribution range was sufficiently accurate for practical purposes. Using these results and records of crop areas, we present risk maps for S. angulatus in agricultural fields. Managers will be able to use these maps to rapidly establish a management plan with minimal cost. Our approach will be valuable for establishing a management plan before or during the early stages of invasion.

  5. Structural mapping from MSS-LANDSAT imagery: A proposed methodology for international geological correlation studies

    NASA Technical Reports Server (NTRS)

    Dejesusparada, N. (Principal Investigator); Crepani, E.; Martini, P. R.

    1980-01-01

    A methodology is proposed for international geological correlation studies based on LANDSAT-MSS imagery, Bullard's model of continental fit and compatible structural trends between Northeast Brazil and the West African counterpart. Six extensive lineaments in the Brazilian study area are mapped and discussed according to their regional behavior and in relation to the adjacent continental margin. Among the first conclusions, correlations were found between the Sobral Pedro II Lineament and the megafaults that surround the West African craton; and the Pernambuco Lineament with the Ngaurandere Linemanet in Cameroon. Ongoing research to complete the methodological stages includes the mapping of the West African structural framework, reconstruction of the pre-drift puzzle, and an analysis of the counterpart correlations.

  6. Laboratory Evaluation of Expedient Low-Temperature Concrete Admixtures for Repairing Blast Holes in Cold Weather

    DTIC Science & Technology

    2013-01-08

    ERDC/CRREL TR-13-1 7 entire solution was cooled to testing temperature (0, −5, or −10°C). The cement was placed into a dry mixing bowl . The mixer...was turned on at low speed and water solution was added. Mixing duration was for 30 seconds. The mixer was stopped, the sides of the bowl were scraped...control dust at construction sites and on some unpaved roads. As an accelerating admixture in concrete, you can use between 1 and 2% of calcium chloride

  7. Ethnic Admixture Affects Diabetes Risk in Native Hawaiians: The Multiethnic Cohort

    PubMed Central

    Maskarinec, Gertraud; Morimoto, Yukiko; Jacobs, Simone; Grandinetti, Andrew; Mau, Marjorie K.; Kolonel, Laurence N.

    2016-01-01

    Background/Objectives Obesity and diabetes rates are high in Native Hawaiians (NH) who commonly have mixed ancestries. Persons of Asian ancestry experience a high risk of type 2 diabetes despite the relatively low body weight. We evaluated the impact of ethnic admixture on diabetes risk among NH in the Multiethnic Cohort (MEC). Methods/Subjects Based on self-reports, 11,521 eligible men and women were categorized into NH/white, NH/other, NH alone, NH/Asian, and the most common three ancestry admixture, NH/Chinese/white. Cox proportional hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated with the NH/white category as the reference group; covariates included known confounders, i.e., body mass index (BMI), dietary and other life-style factors. Results The NH alone category had the highest proportion of overweight and obese individuals and the NH/Asian category the lowest proportion. During 12 years of follow-up after cohort entry at 56 years, 2,072 incident cases were ascertained through questionnaires and health plan linkages. All NH categories had higher HRs than the NH/white category before and after adjustment for BMI. In fully-adjusted models, the NH/Asian category showed the highest risk (HR=1.45; 95%CI: 1.27–1.65), followed by NH/other (HR=1.20; 95%CI: 1.03–1.39), NH/Chinese/white (HR=1.19; 95%CI: 1.04–1.37), and NH alone (HR=1.19; 95%CI: 1.03–1.37). The elevated risk by Asian admixture was more pronounced in normal weight than overweight/obese individuals. Conclusions These findings indicate that Asian admixture in NHs is associated with higher risk for type 2 diabetes independent of known risk factors and suggest a role for ethnicity-related genetic factors in the development of this disease. PMID:27026423

  8. Kinetics of ion admixture in a native gas in an external harmonic electric field

    NASA Astrophysics Data System (ADS)

    Ender, A. Ya.; Ender, I. A.; Gerasimenko, A. B.

    2016-11-01

    We have considered the spatially homogeneous problem of the behavior of an ion admixture in a background gas after applying a harmonic electric field with arbitrary parameters for various laws of interaction of particles. The Boltzmann equation has been solved using the modified method of moments. The ion distribution function and its first moments have been analyzed. It has been shown that the universal analytic expressions for the current density and the ion energy that we derived earlier for a small field amplitude-tofrequency ratio have a considerably wider range of applications.

  9. Genetic structure, relationships and admixture with wild relatives in native pig breeds from Iberia and its islands

    PubMed Central

    2013-01-01

    Background Native pig breeds in the Iberian Peninsula are broadly classified as belonging to either the Celtic or the Mediterranean breed groups, but there are other local populations that do not fit into any of these groups. Most of the native pig breeds in Iberia are in danger of extinction, and the assessment of their genetic diversity and population structure, relationships and possible admixture between breeds, and the appraisal of conservation alternatives are crucial to adopt appropriate management strategies. Methods A panel of 24 microsatellite markers was used to genotype 844 animals representing the 17 most important native swine breeds and wild populations existing in Portugal and Spain and various statistical tools were applied to analyze the results. Results Genetic diversity was high in the breeds studied, with an overall mean of 13.6 alleles per locus and an average expected heterozygosity of 0.80. Signs of genetic bottlenecks were observed in breeds with a small census size, and population substructure was present in some of the breeds with larger census sizes. Variability among breeds accounted for about 20% of the total genetic diversity, and was explained mostly by differences among the Celtic, Mediterranean and Basque breed groups, rather than by differences between domestic and wild pigs. Breeds clustered closely according to group, and proximity was detected between wild pigs and the Mediterranean cluster of breeds. Most breeds had their own structure and identity, with very little evidence of admixture, except for the Retinto and Entrepelado varieties of the Mediterranean group, which are very similar. Genetic influence of the identified breed clusters extends beyond the specific geographical areas across borders throughout the Iberian Peninsula, with a very sharp transition from one breed group to another. Analysis of conservation priorities confirms that the ranking of a breed for conservation depends on the emphasis placed on its

  10. Composts with and without wood ash admixture for the management of tropical acid soils: chemical, physical and microbiological effects

    NASA Astrophysics Data System (ADS)

    Bougnom, B. P.; Insam, H.; Etoa, F. X.

    2009-04-01

    Acid soils generally found in the tropics have a low pH, are poor in organic matter, deficient in Ca2+, Mg+, P, or Mo ; limited in mineralization, nitrification, nodulation, and mycorrhizal infection , suffer from Al or Mn toxicity. Within the framework aiming at using organic wastes and wood ash to overcome soil infertility in tropical acidic soils, a green house experiment was conducted with two acid soils collected from Cameroon (Ferralsol and Acrisol) and amended with three types of compost 3:1(W/W) containing 0 (K0), 8(K8) and 16% (K16) wood ash admixture respectively for two consecutive cycles of 100 days, during which soybean (Glycine max) was grown on the first, the second cycle was left as fallow. Generally the same trends of variation of the physico-chemical parameters were observed in both soils. Addition of organic wastes increased the pH electrical conductivity, soil organic matter, water holding capacity, total Carbone and total nitrogen as compared to the controls. The rate of nitrification highly increased posing the problem of possible leaching of nitrates in the ground water. The cations and micronutrients content followed the same trends. These changes leaded to an increase of the P availability and a decrease of Al toxicity. At the end of the second cycle, generally most of the different parameters slightly decreased except for the electrical conductivity. All composts passed a toxicity test, and the amended soils had significant better fresh and dried plant biomass, the Total nitrogen also significantly increased. Amended soils with K0 generally performed better than those amended with K8 and K16, thinking that their pH (closer to the neutrality) was responsible of these performances, all the parameters were significantly correlated to the pH. K8 and K16 performances could be performed by reducing the added quantities. The study of PCR-DGGE have shown a shift in the fungal and bacterial communities, Ammonia oxidizing bacteria community were

  11. Seaside, Oregon Tsunami Pilot Study - modernization of FEMA flood hazard maps

    USGS Publications Warehouse

    ,

    2006-01-01

    FEMA Flood Insurance Rate Map (FIRM) guidelines do not currently exist for conducting and incorporating tsunami hazard assessments that reflect the substantial advances in tsunami research achieved in the last two decades; this conclusion is the result of two FEMA-sponsored workshops and the associated Tsunami Focused Study. Therefore, as part of FEMA's Map Modernization Program, a Tsunami Pilot Study was carried out in the Seaside/Gearhart, Oregon, area to develop an improved Probabilistic Tsunami Hazard Assessment (PTHA) methodology and to provide recommendations for improved tsunami hazard assessment guidelines. The Seaside area was chosen because it is typical of many coastal communities in the section of the Pacific Coast from Cape Mendocino to the Strait of Juan de Fuca, and because State Agencies and local stakeholders expressed considerable interest in mapping the tsunami threat to this area. The study was an interagency effort by FEMA, U.S. Geological Survey and the National Oceanic and Atmospheric Administration, in collaboration with the University of Southern California, Middle East Technical University. Portland State University, Horning Geosciences, Northwest Hydraulics Consultants, and the Oregon Department of Geological and Mineral Industries. Draft copies and a briefing on the contents, results and recommendations of this document were provided to FEMA officials before final publication.

  12. BOREAS HYD-9 Hourly and Daily Rainfall Maps for the Southern Study Area

    NASA Technical Reports Server (NTRS)

    Eley, F. Joe; Hall, Forrest G. (Editor); Knapp, David E. (Editor); Krauss, Terry S.; Smith, David E. (Technical Monitor)

    2000-01-01

    The Boreal Ecosystem-Atmosphere Study (BOREAS) Hydrology (HYD)-9 team collected data on precipitation and streamflow over portions of the Northern Study Area (NSA) and Southern Study Area (SSA). This data set contains Cartesian maps of rain accumulation for one-hour and daily periods during the summer of 1994 over the SSA only (not the full view of the radar). A parallel set of one-hour maps for the whole radar view has been prepared and is available upon request from the HYD-09 personnel. An incidental benefit of the areal selection was the elimination of some of the less accurate data, because for various reasons the radar rain estimates degrade considerably outside a range of about 100 km. The data are available in tabular ASCII files. The HYD-09 hourly and daily radar rainfall maps for the SSA are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

  13. ATR-FTIR microscopy in mapping mode for the study of verdigris and its secondary products

    NASA Astrophysics Data System (ADS)

    Prati, S.; Bonacini, I.; Sciutto, G.; Genty-Vincent, A.; Cotte, M.; Eveno, M.; Menu, M.; Mazzeo, R.

    2016-01-01

    To study degradation processes occurring on painting materials, the use of high-resolution micro-analytical techniques is highly requested since it provides a detailed identification and localisation of both the original and deteriorated ingredients. Among the various pigments recently studied, the characterisation of verdigris has received a major interest. This pigment has not a unique chemical formula, but its composition depends on the recipe employed for its manufacturing. Moreover, verdigris paints are not stable and are subject to a colour change from blue-green to green, which occurs in the first few months after the application. In this paper, we focused our attention on the use of ATR-FTIR mapping as a useful method to identify verdigris secondary products and pathways. Several mock-ups and real samples have been analysed, and the correlation among the detected compounds and their spatial location, obtained by the application of ATR-FTIR microscopy in mapping mode, allowed formulating some hypotheses on the degradation pattern of verdigris, which may feed the discussion on the transformation and stability of this pigment. From an analytical point of view, we showed how FTIR mapping approaches may be extremely useful both for the identification of compounds in complex matrix in which single spectra may limit the exhaustive characterisations due to bands overlapping and for the study of degradation pathways by taking into consideration the relative distribution of degradation products.

  14. Effect of Expansive Admixtures on the Shrinkage and Mechanical Properties of High-Performance Fiber-Reinforced Cement Composites

    PubMed Central

    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

  15. Synchrotron X-Ray Reciprocal Space Mapping, Topography and Diffraction Resolution Studies of Macromolecular Crystal Quality

    NASA Technical Reports Server (NTRS)

    Boggon, T. J.; Helliwell, J. R.; Judge, Russell A.; Siddons, D. P.; Snell, Edward H.; Stojanoff, V.

    2000-01-01

    A comprehensive study of microgravity and ground grown chicken egg white lysozyme crystals is presented using synchrotron X-ray reciprocal space mapping, topography techniques and diffraction resolution. Microgravity crystals displayed, on average, reduced intrinsic mosaicities but no differences in terms of stress over their earth grown counterparts. Topographic analysis revealed that in the microgravity case the majority of the crystal was contributing to the peak of the reflection at the appropriate Bragg angle. In the earth case at the diffraction peak only a small volume of the crystal contributed to the intensity. The techniques prove to be highly complementary with the reciprocal space mapping providing a quantitative measure of the crystal mosaicity and stress (or variation in lattice spacing) and topography providing a qualitative overall assessment of the crystal in terms of its X-ray diffraction properties. Structural data collection was also carried out both at the synchrotron and in the laboratory.

  16. Historic maps and landscape evolution: a case study in the Little Hungarian Plain

    NASA Astrophysics Data System (ADS)

    Zámolyi, A.; Székely, B.; Draganits, E.; Timár, G.

    2009-04-01

    Georeferenced historic maps provide a useful tool to derive geomorphologic landscape elements largely uninfluenced by anthropogenic activity, thus allowing the study of natural changes in the landscape evolution of increasingly densely populated areas. The study area, the Little Hungarian Plain (LHP), is located at the geologically and geomorphologically highly interesting region at the transition between the mountain chains of the Eastern Alps and the Carpathians. The area, as transport route and exchange zone of goods has had its specific importance since the Neolithic times. Consequently, the environment has been subject to human influence, especially since the onset of the industrial age. Geographically the LHP lies in the vicinity of major settlement areas (Vienna, Bratislava, Sopron, Győr) and stretches from the Leithagebirge, a mountainous area in Eastern Austria, to the City of Győr in Western Hungary. The political division of the area into two separate countries occurred after World War I. Thus, historic mapping in the Habsburg Empire and later in the Austro-Hungarian Monarchy that was organized and conducted before World War I allows a comprehensive overview of the study area. Map sheets of the 2nd Military Survey of the whole Monarchy were mapped in the time from 1807 to 1873 in the area of the entire Empire (Kretschmer et al., 2004). The Kingdom of Hungary, as part of the Empire was mapped in a homogenous campaign in the time from 1819 - 1869. Beside the increasing human impact the area is characterized by active surface processes. The geologic evolution of the Little Hungarian Plain is dominated by tectonic processes related to the lateral extrusion of the Eastern Alps and the acceleration of northward movement of the Carpathians. Subsidence is accommodated mainly along high- and low angle normal faults with a high vertical movement component. Strike-slip movements at these faults are very rare. Most of these processes have been active also in the

  17. Subsidence activity maps derived from DInSAR data: Orihuela case study

    NASA Astrophysics Data System (ADS)

    Sanabria, M. P.; Guardiola-Albert, C.; Tomás, R.; Herrera, G.; Prieto, A.; Sánchez, H.; Tessitore, S.

    2013-10-01

    A new methodology is proposed to produce subsidence activity maps based on the geostatistical analysis of persistent scatterer interferometry (PSI) data. PSI displacement measurements are interpolated based on Conditional Gaussian Simulation (CGS) to calculate multiple equiprobable realizations of subsidence. The result from this process is a series of interpolated subsidence values, with an estimation of the spatial uncertainty and a confidence level on the interpolation. These maps complement the PSI displacement map, improving the identification of wide subsiding areas at regional scale. At local scale, they can be used to identify buildings susceptible to suffer subsidence related damages. In order to do so, it is necessary to calculate the maximum differential settlement and the maximum angular distortion for each building of the study area. Based on PSI derived parameters those buildings in which serviceability limit state has been exceeded, and where in situ forensic analysis should be made, can be automatically identified. This methodology has been tested in Orihuela City (SE Spain) for the study of historical buildings, damaged during the last two decades by subsidence due to aquifer overexploitation.

  18. Subsidence activity maps derived from DInSAR data: Orihuela case study

    NASA Astrophysics Data System (ADS)

    Sanabria, M. P.; Guardiola-Albert, C.; Tomás, R.; Herrera, G.; Prieto, A.; Sánchez, H.; Tessitore, S.

    2014-05-01

    A new methodology is proposed to produce subsidence activity maps based on the geostatistical analysis of persistent scatterer interferometry (PSI) data. PSI displacement measurements are interpolated based on conditional Sequential Gaussian Simulation (SGS) to calculate multiple equiprobable realizations of subsidence. The result from this process is a series of interpolated subsidence values, with an estimation of the spatial variability and a confidence level on the interpolation. These maps complement the PSI displacement map, improving the identification of wide subsiding areas at a regional scale. At a local scale, they can be used to identify buildings susceptible to suffer subsidence related damages. In order to do so, it is necessary to calculate the maximum differential settlement and the maximum angular distortion for each building of the study area. Based on PSI-derived parameters those buildings in which the serviceability limit state has been exceeded, and where in situ forensic analysis should be made, can be automatically identified. This methodology has been tested in the city of Orihuela (SE Spain) for the study of historical buildings damaged during the last two decades by subsidence due to aquifer overexploitation. The qualitative evaluation of the results from the methodology carried out in buildings where damages have been reported shows a success rate of 100%.

  19. A Study of the Effects of Cognitive Mapping on Reading Comprehension and Written Protocols. Technical Report No. 7.

    ERIC Educational Resources Information Center

    Ruddell, Robert; Boyle, Owen

    A study explored how cognitive mapping assists college students in gathering information from long prose passages and organizing this information for subsequent writing. Mapping is a prewriting technique in which students develop a cognitive scheme or graphic representation of a text, which reduces memory load and facilitates integration and…

  20. Analyzing Interactions by an IIS-Map-Based Method in Face-to-Face Collaborative Learning: An Empirical Study

    ERIC Educational Resources Information Center

    Zheng, Lanqin; Yang, Kaicheng; Huang, Ronghuai

    2012-01-01

    This study proposes a new method named the IIS-map-based method for analyzing interactions in face-to-face collaborative learning settings. This analysis method is conducted in three steps: firstly, drawing an initial IIS-map according to collaborative tasks; secondly, coding and segmenting information flows into information items of IIS; thirdly,…

  1. A Study to Determine the Contribution Made by Concept Maps to a Computer Architecture and Organization Course

    ERIC Educational Resources Information Center

    Aydogan, Tuncay; Ergun, Serap

    2016-01-01

    Concept mapping is a method of graphical learning that can be beneficial as a study method for concept linking and organization. Concept maps, which provide an elegant, easily understood representation of an expert's domain knowledge, are tools for organizing and representing knowledge. These tools have been used in educational environments to…

  2. The mouse QTL map helps interpret human genome-wide association studies for HDL cholesterol.

    PubMed

    Leduc, Magalie S; Lyons, Malcolm; Darvishi, Katayoon; Walsh, Kenneth; Sheehan, Susan; Amend, Sarah; Cox, Allison; Orho-Melander, Marju; Kathiresan, Sekar; Paigen, Beverly; Korstanje, Ron

    2011-06-01

    Genome-wide association (GWA) studies represent a powerful strategy for identifying susceptibility genes for complex diseases in human populations but results must be confirmed and replicated. Because of the close homology between mouse and human genomes, the mouse can be used to add evidence to genes suggested by human studies. We used the mouse quantitative trait loci (QTL) map to interpret results from a GWA study for genes associated with plasma HDL cholesterol levels. We first positioned single nucleotide polymorphisms (SNPs) from a human GWA study on the genomic map for mouse HDL QTL. We then used mouse bioinformatics, sequencing, and expression studies to add evidence for one well-known HDL gene (Abca1) and three newly identified genes (Galnt2, Wwox, and Cdh13), thus supporting the results of the human study. For GWA peaks that occur in human haplotype blocks with multiple genes, we examined the homologous regions in the mouse to prioritize the genes using expression, sequencing, and bioinformatics from the mouse model, showing that some genes were unlikely candidates and adding evidence for candidate genes Mvk and Mmab in one haplotype block and Fads1 and Fads2 in the second haplotype block. Our study highlights the value of mouse genetics for evaluating genes found in human GWA studies.

  3. Genome-wide genetic diversity, population structure and admixture analysis in African and Asian cattle breeds.

    PubMed

    Edea, Z; Bhuiyan, M S A; Dessie, T; Rothschild, M F; Dadi, H; Kim, K S

    2015-02-01

    Knowledge about genetic diversity and population structure is useful for designing effective strategies to improve the production, management and conservation of farm animal genetic resources. Here, we present a comprehensive genome-wide analysis of genetic diversity, population structure and admixture based on 244 animals sampled from 10 cattle populations in Asia and Africa and genotyped for 69,903 autosomal single-nucleotide polymorphisms (SNPs) mainly derived from the indicine breed. Principal component analysis, STRUCTURE and distance analysis from high-density SNP data clearly revealed that the largest genetic difference occurred between the two domestic lineages (taurine and indicine), whereas Ethiopian cattle populations represent a mosaic of the humped zebu and taurine. Estimation of the genetic influence of zebu and taurine revealed that Ethiopian cattle were characterized by considerable levels of introgression from South Asian zebu, whereas Bangladeshi populations shared very low taurine ancestry. The relationships among Ethiopian cattle populations reflect their history of origin and admixture rather than phenotype-based distinctions. The high within-individual genetic variability observed in Ethiopian cattle represents an untapped opportunity for adaptation to changing environments and for implementation of within-breed genetic improvement schemes. Our results provide a basis for future applications of genome-wide SNP data to exploit the unique genetic makeup of indigenous cattle breeds and to facilitate their improvement and conservation.

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

    PubMed Central

    2008-01-01

    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. PMID:18644108

  5. Modeling of heat evolution in silicate building materials with electrically conductive admixtures

    NASA Astrophysics Data System (ADS)

    Fiala, Lukáš; Maděra, Jiří; Vejmelková, Eva; Černý, Robert

    2016-12-01

    Silicate building materials are electrically non-conductive, in general. However, a sufficient amount of electrically conductive admixtures can significantly increase their electrical conductivity. Consequently, new practical applications of such materials are available. Materials with enhanced electrical properties can be used as self-sensing sensors monitoring evolution of cracks, electromagnetic shields or cores of deicing systems. This paper deals with the modeling of heat evolution in silicate building materials by the action of passing electric current. Due to the conducting paths formed in the material's matrix by adding a sufficient amount of electrically conductive admixture and applying electric voltage on the installed electrodes, electric current is passing through the material. Thanks to the electric current, Joule heat is successively evolved. As it is crucial to evaluate theoretically the amount of evolved heat in order to assess the effectiveness of such a system, a model describing the Joule heat evolution is proposed and a modeling example based on finite-element method is introduced.

  6. Genetic admixture history of Eastern Indonesia as revealed by Y-chromosome and mitochondrial DNA analysis.

    PubMed

    Mona, Stefano; Grunz, Katharina E; Brauer, Silke; Pakendorf, Brigitte; Castrì, Loredana; Sudoyo, Herawati; Marzuki, Sangkot; Barnes, Robert H; Schmidtke, Jörg; Stoneking, Mark; Kayser, Manfred

    2009-08-01

    Eastern Indonesia possesses more linguistic diversity than any other region in Southeast Asia, with both Austronesian (AN) languages that are of East Asian origin, as well as non-Austronesian (NAN) languages of likely Melanesian origin. Here, we investigated the genetic history of human populations from seven eastern Indonesian islands, including AN and NAN speakers, as well as the relationship between languages and genes, by means of nonrecombining Y-chromosomal (NRY) and mitochondrial DNA (mtDNA) analysis. We found that the eastern Indonesian gene pool consists of East Asian as well as Melanesian components, as might be expected based on linguistic evidence, but also harbors putative indigenous eastern Indonesian signatures that perhaps reflect the initial occupation of the Wallacea by aboriginal hunter-gatherers already in Palaeolithic times. Furthermore, both NRY and mtDNA data showed a complete lack of correlation between linguistic and genetic relationships, most likely reflecting genetic admixture and/or language shift. In addition, we noted a small fraction of the NRY and mtDNA data shared between eastern Indonesians and Australian Aborigines likely reflecting an ancient link between Asia and Australia. Our data thus provide insights into the complex genetic ancestry history of eastern Indonesian islanders characterized by several admixture episodes and demonstrate a clear example of the lack of the often-assumed correlation between the genes and languages of human populations.

  7. Alkali-activated complex binders from class C fly ash and Ca-containing admixtures.

    PubMed

    Guo, Xiaolu; Shi, Huisheng; Chen, Liming; Dick, Warren A

    2010-01-15

    Processes that maximize utilization of industrial solid wastes are greatly needed. Sodium hydroxide and sodium silicate solution were used to create alkali-activated complex binders (AACBs) from class C fly ash (CFA) and other Ca-containing admixtures including Portland cement (PC), flue gas desulfurization gypsum (FGDG), and water treatment residual (WTR). Specimens made only from CFA (CFA100), or the same fly ash mixed with 40 wt% PC (CFA60-PC40), with 10 wt% FGDG (CFA90-FGDG10), or with 10 wt% WTR (CFA90-WTR10) had better mechanical performance compared to binders using other mix ratios. The maximum compressive strength of specimens reached 80.0 MPa. Geopolymeric gel, sodium polysilicate zeolite, and hydrated products coexist when AACB reactions occur. Ca from CFA, PC, and WTR precipitated as Ca(OH)(2), bonded in geopolymers to obtain charge balance, or reacted with dissolved silicate and aluminate species to form calcium silicate hydrate (C-S-H) gel. However, Ca from FGDG probably reacted with dissolved silicate and aluminate species to form ettringite. Utilization of CFA and Ca-containing admixtures in AACB is feasible. These binders may be widely utilized in various applications such as in building materials and for solidification/stabilization of other wastes, thus making the wastes more environmentally benign.

  8. Qaulity-control plan for intravenous admixture programs. II: Validation of operator technique.

    PubMed

    Morris, B G; Avis, K E; Bowles, G C

    1980-05-01

    A plan for the validation of aseptic-operator technique in i.v. admixture programs and two test methods for evaluating the plan are proposed. After a new operator has been trained, the plan involves qualification of the operator through the preparation of statistically valid samples, to be followed by the random selection of samples for in-process monitoring. To test the plan, trypticase soy broth transfers were used in one hospital and Addi-Chek (Millipore Corp.) filtrations were used in another. The participants, all trained operators, initially prepared 40 test samples as a validation step. The finding of no microbial growth in these test samples permitted continuation into the monitoring phase, during which test samples were prepared randomly, one test sample out of every 25 i.v. admixtures prepared for patient use. All samples were negative for microbial growth, indicating that the operators maintained aseptic technique. These findings give evidence that the proposed testing plan is valid. The authors propose the plan as a phase of a quality control program, based on valid statistical principles, to give assurance that i.v. room operators are qualified to prepare sterile parenteral medications.

  9. Genetic variation in Arizona Mexican Americans: estimation and interpretation of admixture proportions.

    PubMed

    Long, J C; Williams, R C; McAuley, J E; Medis, R; Partel, R; Tregellas, W M; South, S F; Rea, A E; McCormick, S B; Iwaniec, U

    1991-02-01

    Mexican Americans are a numerous and fast growing ethnic population in the United States. Yet little is known about their genetic structure. Since they are a hybrid, it is of interest to identify their parental populations and to estimate the relative contributions of these groups. This information is relevant to historical, biomedical, and evolutionary concerns. New genetic typings on 730 Arizona Mexican Americans for the HLA-A, HLA-B, ABO, Rh, MNSs, Duffy, Kidd, and Kell loci are presented here and they are used to estimate ancestral contributions. We considered both a dihybrid model with Amerindians and Spaniards as proposed ancestors, and a trihybrid model with Amerindians, Spaniards, and Africans as proposed ancestors. A modified weighted least squares method that allows for linkage disequilibrium was used to estimate ancestral contributions for each model. The following admixture estimates were obtained: Amerindian, 0.29 +/- 0.04; Spaniard, 0.68 +/- 0.05; and African, 0.03 +/- 0.02. The interpretation of these results with respect to Amerindian and Spanish ancestry is straightforward. African ancestry is strongly supported by the presence of a marker of African descent, Fy, despite the fact that the standard error of the estimate is as large as the estimated admixture proportion. An evaluation of the sensitivity of these results to a number of variables is presented: 1) our choices of ancestral allele frequencies, 2) the possibility of selection at HLA and the blood groups, and 3) genetic drift in Mexican Americans.

  10. Stability of cefazolin sodium and metronidazole at 8 degrees C for use as an i.v. admixture.

    PubMed

    Rivers, T E; McBride, H A; Trang, J M

    1993-01-01

    The stability of cefazolin 1 g in metronidazole 500 mg/100 mL at 8 degrees C was studied for use as an IV admixture. The commercially available injection of cefazolin sodium 1 g vial was diluted to 5 mL with 0.9% sodium chloride injection and added to metronidazole 500 mg/100 mL. Following dilution of 2 mL to 100 mL with water, 1-mL aliquots were transferred to glass vials, refrigerated at 8 degrees, and assayed for cefazolin and metronidazole concentration at 0, 1, 2, 4, 8, 12, 24, 36, 48, and 72 hours after preparation. The concentration of cefazolin and metronidazole was determined by a stability-indicating high-performance liquid chromatographic method. The range of concentration was determined to be within 5% of the 0-hour mean concentration. Over the 72-hour period, the mean concentration of cefazolin at all assay times was within 98.4 to 101.0% of the initial concentration. The mean concentration of metronidazole at each assay time was 96.9 to 104.9% of the initial concentration. Cefazolin sodium 10 mg/mL and metronidazole 5 mg/mL, prepared by adding reconstituted cefazolin to a glass bottle of metronidazole ready-to-use solution, were stable for 72 hours when stored at 8 degrees C.

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

    NASA Astrophysics Data System (ADS)

    Dmitriyenko, Margarita A.; Nyashina, Galina S.; Zhdanova, Alena O.; Vysokomornaya, Olga V.

    2016-02-01

    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.

  12. Maps of Ventricular Activation Time (VAT) Differences in Children on Peritoneal Dialysis — a Pilot Study

    PubMed Central

    Laszki-Szcząchor, Krystyna; Polak-Jonkisz, Dorota; Zwolińska, Danuta; Salomon, Ewa; Filipowski, Henryk; Sobieszczańska, Małgorzata

    2015-01-01

    ♦ Background: Decrement of glomerular filtration rate leads to many serious complications that cause both functional and structural impairments of the other organs. Long-term clinical observations of children and teenagers with end-stage renal disease (ESRD) showed that more than one third of those patients manifested various cardio-vascular conditions. The aim of the study was to analyze possible disturbances in the heart ventricular conduction system by using a technique of ventricular activation time (VAT) differences in ESRF children on peritoneal dialysis (PD) with normal electrocardiogram (ECG) examinations. ♦ Material and methods: The study group comprised 10 ESRD children (mean age: 13.6 ± 2.31 years) on peritoneal dialysis – group I. The control group (group II) consisted of 26 age-matched healthy children with no clinical evidence of renal or cardiac disease and with normal 12-lead ECG recordings. Each of the ESRD patients was also subjected to the standard ECG examination. In order to capture possible heart conduction abnormalities, body surface potential mapping (BSPM) recordings were performed in PD patients between the successive dwells (‘on empty abdomen’) with a HPM-7100 Fukuda Denshi system. Based on the source ECG data, the original technique of a VAT difference map was then applied. ♦ Results: Differences between VAT values for the two examined groups of children, controls and ESRD patients on PD, were significantly pronounced in the region of the right upper anterior thorax, the entire left thorax and nearly in the total back. Such a pattern of VAT delays indicates a pathological electric transmission in the intraventricular conduction system of the left anterior fascicle of His bundle. ♦ Conclusion: 1. VAT maps (isochrone maps) can be useful to detect abnormal spreading and depolarization through the heart ventricles. 2. Map of VAT value differences makes it possible to identify early disturbances in the left His bundle branch in

  13. Study on High Accuracy Topographic Mapping via UAV-based Images

    NASA Astrophysics Data System (ADS)

    Chi, Yun-Yao; Lee, Ya-Fen; Tsai, Shang-En

    2016-10-01

    Unmanned aerial vehicle (UAV) provides a promising tool for the acquisition of such multi-temporal aerial stereo photos and high-resolution digital surface models. Recently, the flight of UAVs operates with high degrees of autonomy by the global position system and onboard digit camera and computer. The UAV-based mapping can be obtained faster and cheaper, but its accuracy is anxious. This paper aims to identify the integration ability of high accuracy topographic map via the image of quad-rotors UAV and ground control points (GCPs). The living survey data is collected in the Errn river basins area in Tainan, Taiwan. The high accuracy UAV-based topographic in the study area is calibrated by the local coordinate of GCPs using the total station with the accuracy less than 1/2000. The comparison results show the accuracy of UAV-based topographic is accepted by overlapping. The results can be a reference for the practice works of mapping survey in earth.

  14. New leads for selective GSK-3 inhibition: pharmacophore mapping and virtual screening studies

    NASA Astrophysics Data System (ADS)

    Patel, Dhilon S.; Bharatam, Prasad V.

    2006-01-01

    Glycogen Synthase Kinase-3 is a regulatory serine/threonine kinase, which is being targeted for the treatment of a number of human diseases including type-2 diabetes mellitus, neurodegenerative diseases, cancer and chronic inflammation. Selective GSK-3 inhibition is an important requirement owing to the possibility of side effects arising from other kinases. A pharmacophore mapping strategy is employed in this work to identify new leads for selective GSK-3 inhibition. Ligands known to show selective GSK-3 inhibition were employed in generating a pharmacophore map using distance comparison method (DISCO). The derived pharmacophore map was validated using (i) important interactions involved in selective GSK-3 inhibitions, and (ii) an in-house database containing different classes of GSK-3 selective, non-selective and inactive molecules. New Lead identification was carried out by performing virtual screening using validated pharmacophoric query and three chemical databases namely NCI, Maybridge and Leadquest. Further data reduction was carried out by employing virtual filters based on (i) Lipinski's rule of 5 (ii) van der Waals bumps and (iii) restricting the number of rotatable bonds to seven. Final screening was carried out using FlexX based molecular docking study.

  15. New leads for selective GSK-3 inhibition: pharmacophore mapping and virtual screening studies.

    PubMed

    Patel, Dhilon S; Bharatam, Prasad V

    2006-01-01

    Glycogen Synthase Kinase-3 is a regulatory serine/threonine kinase, which is being targeted for the treatment of a number of human diseases including type-2 diabetes mellitus, neurodegenerative diseases, cancer and chronic inflammation. Selective GSK-3 inhibition is an important requirement owing to the possibility of side effects arising from other kinases. A pharmacophore mapping strategy is employed in this work to identify new leads for selective GSK-3 inhibition. Ligands known to show selective GSK-3 inhibition were employed in generating a pharmacophore map using distance comparison method (DISCO). The derived pharmacophore map was validated using (i) important interactions involved in selective GSK-3 inhibitions, and (ii) an in-house database containing different classes of GSK-3 selective, non-selective and inactive molecules. New Lead identification was carried out by performing virtual screening using validated pharmacophoric query and three chemical databases namely NCI, Maybridge and Leadquest. Further data reduction was carried out by employing virtual filters based on (i) Lipinski's rule of 5 (ii) van der Waals bumps and (iii) restricting the number of rotatable bonds to seven. Final screening was carried out using FlexX based molecular docking study.

  16. Mapping Soil Surface Macropores Using Infrared Thermography: An Exploratory Laboratory Study

    PubMed Central

    de Lima, João L. M. P.; Abrantes, João R. C. B.; Silva, Valdemir P.; de Lima, M. Isabel P.; Montenegro, Abelardo A. A.

    2014-01-01

    Macropores and water flow in soils and substrates are complex and are related to topics like preferential flow, nonequilibrium flow, and dual-continuum. Hence, the quantification of the number of macropores and the determination of their geometry are expected to provide a better understanding on the effects of pores on the soil's physical and hydraulic properties. This exploratory study aimed at evaluating the potential of using infrared thermography for mapping macroporosity at the soil surface and estimating the number and size of such macropores. The presented technique was applied to a small scale study (laboratory soil flume). PMID:25371915

  17. Comprehensive personal RF-EMF exposure map and its potential use in epidemiological studies.

    PubMed

    Gonzalez-Rubio, Jesus; Najera, Alberto; Arribas, Enrique

    2016-08-01

    In recent years, numerous epidemiological studies, which deal with the potential effects of mobile phone antennas on health, have almost exclusively focused on their distance to mobile phone base stations. Although it is known that this is not the best approach to the problem, this situation occurs due to the numerous difficulties when determining the personal exposure to the radiofrequency electromagnetic fields (RF-EMF). However, due to the rise of personal exposimeters, the evolution of spatial statistics, the development of geographical information systems and the use of powerful software, new alternatives are available to deal with these epidemiological studies and thus overcome the aforementioned difficulties. Using these tools, this paper presents a lattice map of personal RF-EMF exposure from exterior mobile phone base stations, covering the entire 110 administrative regions in the city of Albacete (Spain). For this purpose, we used a personal exposimeter, Satimo EME Spy 140 model, performing measurements every 4s The exposimeter was located inside the plastic basket of a bicycle, whose versatility permitted the access to all the zones of the city. Once the exposure map was prepared, its relation with the known antenna locations was studied. The 64 mobile telephone antennas of the city were also georeferenced; the randomness of both variables (exposure and antennas) were studied by means of the Moran's I test. Results showed that the distribution of the antennas follows a grouped pattern (p<0.001), while the distribution of the average exposure values have a random distribution (p=0.618). In addition, we showed two Spearman correlation studies: the first between the average exposure values and the number of mobile telephone antennas per administrative region, and the second, also considering the antennas of the neighbouring regions. No substantial correlation was detected in either of the two cases. This study also reveals the weaknesses of the

  18. Mineral classification map using MF and SAM techniques: A case study in the Nohwa Island, Korea

    SciTech Connect

    Son, Young-Sun; Yoon, Wang-Jung

    2015-03-10

    The purpose of this study is to map pyprophyllite distribution at surface of the Nohwa deposit, Korea by using Advanced Spaceborne Thermal Emission and Reflectance Radiometer (ASTER) data. For this, combined Spectral Angle Mapper (SAM), and Matched Filtering (MF) technique based on mathematical algorithm was applied. The regional distribution of high-grade and low-grade pyrophyllite in the Nohwa deposit area could be differentiated by this method. The results of this study show that ASTER data analysis using combination of SAM and MF techniques will assist in exploration of pyrophyllite at the exposed surface.

  19. A study of kindergarten children's spatial representation in a mapping project

    NASA Astrophysics Data System (ADS)

    Davis, Genevieve A.; Hyun, Eunsook

    2005-02-01

    This phenomenological study examined kindergarten children's development of spatial representation in a year long mapping project. Findings and discussion relative to how children conceptualised and represented physical space are presented in light of theoretical notions advanced by Piaget, van Hiele, and cognitive science researchers Battista and Clements. Analyses of the processes the children used and their finished products indicate that children can negotiate meaning for complex systems of geometric concepts when given opportunities to debate, negotiate, reflect, evaluate and seek meaning for representing space. The complexity and "holistic" nature of spatial representation of young children emerged in this study.

  20. Signal-to-noise analysis of cerebral blood volume maps from dynamic NMR imaging studies.

    PubMed

    Boxerman, J L; Rosen, B R; Weisskoff, R M

    1997-01-01

    The use of cerebral blood volume (CBV) maps generated from dynamic MRI studies tracking the bolus passage of paramagnetic contrast agents strongly depends on the signal-to-noise ratio (SNR) of the maps. The authors present a semianalytic model for the noise in CBV maps and introduce analytic and Monte Carlo techniques for determining the effect of experimental parameters and processing strategies upon CBV-SNR. CBV-SNR increases as more points are used to estimate the baseline signal level. For typical injections, maps made with 10 baseline points have 34% more noise than those made with 50 baseline points. For a given peak percentage signal drop, an optimum TE can be chosen that, in general, is less than the baseline T2. However, because CBV-SNR is relatively insensitive to TE around this optimum value, choosing TE approximately equal to T2 does not sacrifice much SNR for typical doses of contrast agent. The TR that maximizes spin-echo CBV-SNR satisfies TR/T1 approximately equal to 1.26, whereas as short a TR as possible should be used to maximize gradient-echo CBV-SNR. In general, CBV-SNR is maximized for a given dose of contrast agent by selecting as short an input bolus duration as possible. For image SNR exceeding 20-30, the gamma-fitting procedure adds little extra noise compared with simple numeric integration. However, for noisier input images, can be the case for high resolution echo-planar images, the covarying parameters of the gamma-variate fit broaden the distribution of the CBV estimate and thereby decrease CBV-SNR. The authors compared the analytic noise predicted by their model with that of actual patient data and found that the analytic model accounts for roughly 70% of the measured variability of CBV within white matter regions of interest.

  1. Regional mapping of forest canopy water content and biomass using AIRSAR images over BOREAS study area

    NASA Technical Reports Server (NTRS)

    Saatchi, Sasan; Rignot, Eric; Vanzyl, Jakob

    1995-01-01

    In recent years, monitoring vegetation biomass over various climate zones has become the primary focus of several studies interested in assessing the role of the ecosystem responses to climate change and human activities. Airborne and spaceborne Synthetic Aperture Radar (SAR) systems provide a useful tool to directly estimate biomass due to its sensitivity to structural and moisture characteristics of vegetation canopies. Even though the sensitivity of SAR data to total aboveground biomass has been successfully demonstrated in many controlled experiments over boreal forests and forest plantations, so far, no biomass estimation algorithm has been developed. This is mainly due to the fact that the SAR data, even at lowest frequency (P-band) saturates at biomass levels of about 200 tons/ha, and the structure and moisture information in the SAR signal forces the estimation algorithm to be forest type dependent. In this paper, we discuss the development of a hybrid forest biomass algorithm which uses a SAR derived land cover map in conjunction with a forest backscatter model and an inversion algorithm to estimate forest canopy water content. It is shown that unlike the direct biomass estimation from SAR data, the estimation of water content does not depend on the seasonal and/or environmental conditions. The total aboveground biomass can then be derived from canopy water content for each type of forest by incorporating other ecological information. Preliminary results from this technique over several boreal forest stands indicate that (1) the forest biomass can be estimated with reasonable accuracy, and (2) the saturation level of the SAR signal can be enhanced by separating the crown and trunk biomass in the inversion algorithm. We have used the JPL AIRSAR data over BOREAS southern study area to test the algorithm and to generate regional scale water content and biomass maps. The results are compared with ground data and the sources of errors are discussed. Several SAR

  2. Methodology for Elaborating Regional Susceptibility Maps of Slope Instability: the State of Guerrero (mexico) Case Study

    NASA Astrophysics Data System (ADS)

    González Huesca, A. E.; Ferrés, D.; Domínguez-M, L.

    2013-05-01

    Numerous cases of different types of slope instability occur every year in the mountain areas of México. Sometimes these instabilities severely affect the exposed communities, roads and infrastructure, causing deaths and serious material damage, mainly in the states of Puebla, Veracruz, Oaxaca, Guerrero and Chiapas, at the central and south sectors of the country. The occurrence of the slope instability is the result of the combination of climatic, geologic, hydrologic, geomorphologic and anthropogenic factors. The National Center for Disaster Prevention (CENAPRED) is developing several projects in order to offer civil protection authorities of the Mexican states some methodologies to address the hazard assessment for different natural phenomena in a regional level. In this framework, during the past two years, a methodology was prepared to construct susceptibility maps for slope instability at regional (≤ 1:100 000) and national (≤ 1:1 000 000) levels. This research was addressed in accordance to the criteria established by the International Association of Engineering Geology, which is the highest international authority in this topic. The state of Guerrero has been taken as a pilot scheme to elaborate the susceptibility map for slope instability at a regional level. The major constraints considered in the methodology to calculate susceptibility are: a) the slope of the surface, b) the geology and c) the land use, which were integrated using a Geographic Information System (GIS). The arithmetic sum and weighting factors to obtain the final susceptibility map were based on the average values calculated in the individual study of several cases of slope instability occurred in the state in the past decade. For each case, the evaluation format proposed by CENAPRED in 2006 in the "Guía Básica para la elaboración de Atlas Estatales y Municipales de Peligros y Riesgos" to evaluate instabilities in a local level, was applied. The resulting susceptibility map shows

  3. Landslide hazard mapping with selected dominant factors: A study case of Penang Island, Malaysia

    SciTech Connect

    Tay, Lea Tien; Alkhasawneh, Mutasem Sh.; Ngah, Umi Kalthum; Lateh, Habibah

    2015-05-15

    Landslide is one of the destructive natural geohazards in Malaysia. In addition to rainfall as triggering factos for landslide in Malaysia, topographical and geological factors play important role in the landslide susceptibility analysis. Conventional topographic factors such as elevation, slope angle, slope aspect, plan curvature and profile curvature have been considered as landslide causative factors in many research works. However, other topographic factors such as diagonal length, surface area, surface roughness and rugosity have not been considered, especially for the research work in landslide hazard analysis in Malaysia. This paper presents landslide hazard mapping using Frequency Ratio (FR) and the study area is Penang Island of Malaysia. Frequency ratio approach is a variant of probabilistic method that is based on the observed relationships between the distribution of landslides and each landslide-causative factor. Landslide hazard map of Penang Island is produced by considering twenty-two (22) landslide causative factors. Among these twenty-two (22) factors, fourteen (14) factors are topographic factors. They are elevation, slope gradient, slope aspect, plan curvature, profile curvature, general curvature, tangential curvature, longitudinal curvature, cross section curvature, total curvature, diagonal length, surface area, surface roughness and rugosity. These topographic factors are extracted from the digital elevation model of Penang Island. The other eight (8) non-topographic factors considered are land cover, vegetation cover, distance from road, distance from stream, distance from fault line, geology, soil texture and rainfall precipitation. After considering all twenty-two factors for landslide hazard mapping, the analysis is repeated with fourteen dominant factors which are selected from the twenty-two factors. Landslide hazard map was segregated into four categories of risks, i.e. Highly hazardous area, Hazardous area, Moderately hazardous area

  4. Maps showing aeromagnetic survey and interpretation of the Virgin Mountains Instant Study Area Clark County, Nevada

    USGS Publications Warehouse

    Griscom, Andrew

    1980-01-01

    Data for the aeromagnetic map (fig. 1) of the Virgin Mountains Instant Study Area wre collected in 1978 and compiled at a scale of 1:62,500. North-south traverses were spaced at 0.8-km intervals at an altitude of about 300m above the surface of the ground. The contour interval is 20 and 100 gammas, depending on the steepness of local magnetic gradients in the Earth's magnetic field. A regional field  (the International Geomagnetic Reference Field - 1975) of approximately 5-6 gammas/km was removed from the data before contouring by computer. 

  5. A Three-Tier System for Assessing Concept Map Links: A Methodological Study.

    ERIC Educational Resources Information Center

    Nicoll, Gayle; Francisco, Joseph; Nakhleh, Mary

    2001-01-01

    Describes a novel method for analyzing concept maps for research and analysis purposes. Examines 56 complex concept maps generated from student interviews on the topic of chemical bonding. (Contains 32 references.) (Author/YDS)

  6. A concept mapping study on organic food consumers in Shanghai, China.

    PubMed

    Hasimu, Huliyeti; Marchesini, Sergio; Canavari, Maurizio

    2017-01-01

    Despite some similarities with developed countries, the growth of organic market in China seems to follow a different path. Thus, important questions are how Chinese urban consumers perceive organic food, and what are the main concepts associated to the organic attribute. We aimed at representing in graphic form the network of mental associations with the organic concept. We used an adapted version of the "Brand concept mapping" method to acquire, process, and draw individual concept networks perceived by 50 organic food consumers in Shanghai. We then analyzed the data using network and cluster analysis to create aggregated maps for two distinct groups of consumers. Similarly to their peers in developed countries, Chinese consumers perceive organic food as healthy, safe and expensive. However, organic is not necessarily synonymous with natural produce in China, also due to a translation of the term that conveys the idea of a "technology advanced" product. Organic overlaps with the green food label in terms of image and positioning in the market, since they are easily associated and often confused. The two groups we identified show clear differences in the way the organic concept is associated to other concepts and features. The study provides useful information for practitioners: marketers of organic products in China should invest in communication to emphasize the differences with Green Food products and they should consider the possibility of segmenting organic consumers; Chinese policy makers should consider implementing information campaigns aimed at achieving a better understanding of the features of these quality labels among consumers. For researchers, the study confirms that the BCM method is effective and its integration with network and cluster analysis improves the interpretation of individual and aggregated maps.

  7. Salt Repository Project site study plan for surface geological mapping: Revision 1, December 22, 1987

    SciTech Connect

    Not Available

    1988-03-01

    This site study plan describes the Surface Geological Mapping field activities to be conducted during early stages of Site Characterization for the Deaf Smith County Site, Texas. The field program has been designed to provide data useful in addressing information and design data needs resulting from Federal/State/local regulatory requirements and repository program requirements. Air and ground surveys and an extensive literature search will be conducted to map areas within and hear proposed nuclear waste repository site in the Deaf Smith County. Findings from this study may identify additional areas requiring further investigation, for which a new site study plan will be prepared. The Salt Repository Project (SRP) Networks specify the schedule under which the program will operate. The Technical and Field Services Contractor (TFSC) is responsible for conducting the field program. Data will be handled and reported in accordance with established SRP procedures. A quality assurance program will be utilized to assure that activities affecting quality are performed correctly and the appropriate documentation is maintained. 27 refs., 13 figs., 5 tabs.

  8. Admixture dynamics in Hispanics: a shift in the nuclear genetic ancestry of a South American population isolate.

    PubMed

    Bedoya, Gabriel; Montoya, Patricia; García, Jenny; Soto, Ivan; Bourgeois, Stephane; Carvajal, Luis; Labuda, Damian; Alvarez, Victor; Ospina, Jorge; Hedrick, Philip W; Ruiz-Linares, Andrés

    2006-05-09

    Although it is well established that Hispanics generally have a mixed Native American, African, and European ancestry, the dynamics of admixture at the foundation of Hispanic populations is heterogeneous and poorly documented. Genetic analyses are potentially very informative for probing the early demographic history of these populations. Here we evaluate the genetic structure and admixture dynamics of a province in northwest Colombia (Antioquia), which prior analyses indicate was founded mostly by Spanish men and native women. We examined surname, Y chromosome, and mtDNA diversity in a geographically structured sample of the region and obtained admixture estimates with highly informative autosomal and X chromosome markers. We found evidence of reduced surname diversity and support for the introduction of several common surnames by single founders, consistent with the isolation of Antioquia after the colonial period. Y chromosome and mtDNA data indicate little population substructure among founder Antioquian municipalities. Interestingly, despite a nearly complete Native American mtDNA background, Antioquia has a markedly predominant European ancestry at the autosomal and X chromosome level, which suggests that, after foundation, continuing admixture with Spanish men (but not with native women) increased the European nuclear ancestry of Antioquia. This scenario is consistent with historical information and with results from population genetics theory.

  9. Admixture dynamics in Hispanics: A shift in the nuclear genetic ancestry of a South American population isolate

    PubMed Central

    Bedoya, Gabriel; Montoya, Patricia; García, Jenny; Soto, Ivan; Bourgeois, Stephane; Carvajal, Luis; Labuda, Damian; Alvarez, Victor; Ospina, Jorge; Hedrick, Philip W.; Ruiz-Linares, Andrés

    2006-01-01

    Although it is well established that Hispanics generally have a mixed Native American, African, and European ancestry, the dynamics of admixture at the foundation of Hispanic populations is heterogeneous and poorly documented. Genetic analyses are potentially very informative for probing the early demographic history of these populations. Here we evaluate the genetic structure and admixture dynamics of a province in northwest Colombia (Antioquia), which prior analyses indicate was founded mostly by Spanish men and native women. We examined surname, Y chromosome, and mtDNA diversity in a geographically structured sample of the region and obtained admixture estimates with highly informative autosomal and X chromosome markers. We found evidence of reduced surname diversity and support for the introduction of several common surnames by single founders, consistent with the isolation of Antioquia after the colonial period. Y chromosome and mtDNA data indicate little population substructure among founder Antioquian municipalities. Interestingly, despite a nearly complete Native American mtDNA background, Antioquia has a markedly predominant European ancestry at the autosomal and X chromosome level, which suggests that, after foundation, continuing admixture with Spanish men (but not with native women) increased the European nuclear ancestry of Antioquia. This scenario is consistent with historical information and with results from population genetics theory. PMID:16648268

  10. Physicochemical stability of ternary admixtures of butorphanol, ketamine, and droperidol in polyolefin bags for patient-controlled analgesia use

    PubMed Central

    Fang, Baoxia; Wang, Linhai; Gu, Junfeng; Chen, Fuchao; Shi, Xiao-ya

    2016-01-01

    Background Delivery of drug admixtures by intravenous patient-controlled analgesia is a common practice for the management of postoperative pain; however, analytical confirmation of the compatibility and stability of butorphanol tartrate, ketamine hydrochloride, and droperidol combined in ternary admixtures is not available. Methods Butorphanol tartrate, ketamine hydrochloride, and droperidol have been examined for compatibility and stability when combined with 0.9% sodium chloride injection stored at 4°C and 25°C with light protection for a total of 14 days. Concentrations were 0.067 mg/mL, 1.33 mg/mL, and 0.033 mg/mL for butorphanol tartrate, ketamine hydrochloride, and droperidol, respectively. Drug concentrations were determined using high-performance liquid chromatographic analysis. Results All three drugs were very stable (>97%) at 4°C and 25°C for 14 days. The ternary admixtures were initially clear and colorless throughout the observation period, and the pH value did not change significantly. Conclusion The results confirm that the ternary admixture of butorphanol tartrate 0.067 mg/mL, ketamine hydrochloride 1.33 mg/mL, and droperidol 0.033 mg/mL in 0.9% sodium chloride injection were stable for 14 days when stored in polyolefin bags at 4°C and 25°C and protected from light. PMID:27920502

  11. Forgotten forests - issues and prospects in biome mapping using Seasonally Dry Tropical Forests as a case study

    PubMed Central

    2011-01-01

    Background South America is one of the most species diverse continents in the world. Within South America diversity is not distributed evenly at both local and continental scales and this has led to the recognition of various areas with unique species assemblages. Several schemes currently exist which divide the continental-level diversity into large species assemblages referred to as biomes. Here we review five currently available biome maps for South America, including the WWF Ecoregions, the Americas basemap, the Land Cover Map of South America, Morrone's Biogeographic regions of Latin America, and the Ecological Systems Map. The comparison is performed through a case study on the Seasonally Dry Tropical Forest (SDTF) biome using herbarium data of habitat specialist species. Results Current biome maps of South America perform poorly in depicting SDTF distribution. The poor performance of the maps can be attributed to two main factors: (1) poor spatial resolution, and (2) poor biome delimitation. Poor spatial resolution strongly limits the use of some of the maps in GIS applications, especially for areas with heterogeneous landscape such as the Andes. Whilst the Land Cover Map did not suffer from poor spatial resolution, it showed poor delimitation of biomes. The results highlight that delimiting structurally heterogeneous vegetation is difficult based on remote sensed data alone. A new refined working map of South American SDTF biome is proposed, derived using the Biome Distribution Modelling (BDM) approach where georeferenced herbarium data is used in conjunction with bioclimatic data. Conclusions Georeferenced specimen data play potentially an important role in biome mapping. Our study shows that herbarium data could be used as a way of ground-truthing biome maps in silico. The results also illustrate that herbarium data can be used to model vegetation maps through predictive modelling. The BDM approach is a promising new method in biome mapping, and could be

  12. Detecting directional selection in the presence of recent admixture in African-Americans.

    PubMed

    Lohmueller, Kirk E; Bustamante, Carlos D; Clark, Andrew G

    2011-03-01

    We investigate the performance of tests of neutrality in admixed populations using plausible demographic models for African-American history as well as resequencing data from African and African-American populations. The analysis of both simulated and human resequencing data suggests that recent admixture does not result in an excess of false-positive results for neutrality tests based on the frequency spectrum after accounting for the population growth in the parental African population. Furthermore, when simulating positive selection, Tajima's D, Fu and Li's D, and haplotype homozygosity have lower power to detect population-specific selection using individuals sampled from the admixed population than from the nonadmixed population. Fay and Wu's H test, however, has more power to detect selection using individuals from the admixed population than from the nonadmixed population, especially when the selective sweep ended long ago. Our results have implications for interpreting recent genome-wide scans for positive selection in human populations.

  13. Genomic diversity and admixture differs for Stone-Age Scandinavian foragers and farmers.

    PubMed

    Skoglund, Pontus; Malmström, Helena; Omrak, Ayça; Raghavan, Maanasa; Valdiosera, Cristina; Günther, Torsten; Hall, Per; Tambets, Kristiina; Parik, Jüri; Sjögren, Karl-Göran; Apel, Jan; Willerslev, Eske; Storå, Jan; Götherström, Anders; Jakobsson, Mattias

    2014-05-16

    Prehistoric population structure associated with the transition to an agricultural lifestyle in Europe remains a contentious idea. Population-genomic data from 11 Scandinavian Stone Age human remains suggest that hunter-gatherers had lower genetic diversity than that of farmers. Despite their close geographical proximity, the genetic differentiation between the two Stone Age groups was greater than that observed among extant European populations. Additionally, the Scandinavian Neolithic farmers exhibited a greater degree of hunter-gatherer-related admixture than that of the Tyrolean Iceman, who also originated from a farming context. In contrast, Scandinavian hunter-gatherers displayed no significant evidence of introgression from farmers. Our findings suggest that Stone Age foraging groups were historically in low numbers, likely owing to oscillating living conditions or restricted carrying capacity, and that they were partially incorporated into expanding farming groups.

  14. Admixture is a driver rather than a passenger in experimental invasions.

    PubMed

    Hufbauer, Ruth A

    2017-01-01

    Genetic admixture propels invasions of Callosobruchus maculatus across experimental landscapes. In Focus: Wagner, N.K., Ochocki, B.M., Crawford, K.M., Compagnoni, A. & Miller, T.E.X. (2017) Genetic mixture of multiple source populations accelerates invasive range expansion. Journal of Animal Ecology, 86, 21-34. In this issue of Journal of Animal Ecology, Wagner et al. (2017) demonstrate that genetic diversity can alter the course of spread of biological invasions. They employ Callosobruchus seed beetles in a clever array of linked habitat patches to compare experimental invasions using individuals from single population sources or from mixes of two, four or six population sources. By taking a model-selection approach, they find that any amount of mixture propels growth rates and spread of introduced populations. This suggests that heterosis alone can alter the course of an invasive range expansion.

  15. Performance of corrosion inhibiting admixtures for structural concrete -- assessment methods and predictive modeling

    SciTech Connect

    Yunovich, M.; Thompson, N.G.

    1998-12-31

    During the past fifteen years corrosion inhibiting admixtures (CIAs) have become increasingly popular for protection of reinforced components of highway bridges and other structures from damage induced by chlorides. However, there remains considerable debate about the benefits of CIAs in concrete. A variety of testing methods to assess the performance of CIA have been reported in the literature, ranging from tests in simulated pore solutions to long-term exposures of concrete slabs. The paper reviews the published techniques and recommends the methods which would make up a comprehensive CIA effectiveness testing program. The results of this set of tests would provide the data which can be used to rank the presently commercially available CIA and future candidate formulations utilizing a proposed predictive model. The model is based on relatively short-term laboratory testing and considers several phases of a service life of a structure (corrosion initiation, corrosion propagation without damage, and damage to the structure).

  16. [Contact and admixture-the relationship between Dongxiang population and their language viewed from Y chromosomes].

    PubMed

    Wen, Shao-Qing; Xie, Xiao-Dong; Xu, Dan

    2013-06-01

    Dongxiang is one of special ethnic groups of Gansu Province. Their language is one of the Mongolian languages of Altai language family. And their origin has long been controversial. The results of Cluster analyses (multidimensional scaling analysis, dendrograms, principal component analyses, and networks) of Dongxiang population and other ethnic groups indicated that Dongxiang people is much closer to the Central Asian ethnic groups than to the other Mongolian. Admixture analyses also confirmed the result. This suggests that Dongxiang people did not descend from Mongolian, but from the Central Asian ethnic groups that have spoken Persian or Turkic language. This mismatch between paternal genetic lineage and language classification might be explained by the elite-dominance model. The ancestral populations of Dongxiang could be the Central Asian ethnic groups assimilated by Mongolian in language and culture.

  17. Concentric Ring Method for generating pollen maps. Quercus as case study.

    PubMed

    Oteros, Jose; Valencia, Rosa Mª; Del Río, Sara; Vega, Ana Mª; García-Mozo, Herminia; Galán, Carmen; Gutiérrez, Pablo; Mandrioli, Paolo; Fernández-González, Delia

    2017-01-15

    Mapping pollen concentrations is of great interest to study the health impact and ecological implications or for forestry or agronomical purposes. A deep knowledge about factors affecting airborne pollen is essential for predicting and understanding its dynamics. The present work sought to predict annual Quercus pollen over the Castilla and León region (Central and Northern Spain). Also to understand the relationship between airborne pollen and landscape. Records of Quercus and Quercus pyrenaica pollen types were collected at 13 monitoring sites over a period of 8years. They were analyzed together with land use data applying the Concentric Ring Method (CRM), a technique that we developed to study the relationship between airborne particle concentrations and emission sources in the region. The maximum correlation between the Quercus pollen and forms of vegetation was determined by shrubland and "dehesa" areas. For the specific Qi pyrenaica model (Q. pyrenaica pollen and Q. pyrenaica forest distribution), the maximum influence of emission sources on airborne pollen was observed at 14km from the pollen trap location with some positive correlations up to a distance of 43km. Apart from meteorological behavior, the local features of the region can explain pollen dispersion patterns. The method that we develop here proved to be a powerful tool for multi-source pollen mapping based on land use.

  18. Using MatContM in the study of a nonlinear map in economics

    NASA Astrophysics Data System (ADS)

    Neirynck, Niels; Al-Hdaibat, Bashir; Govaerts, Willy; Kuznetsov, Yuri A.; Meijer, Hil G. E.

    2016-02-01

    MatContM is a MATLAB interactive toolbox for the numerical study of iterated smooth maps, their Lyapunov exponents, fixed points, and periodic, homoclinic and heteroclinic orbits as well as their stable and unstable invariant manifolds. The bifurcation analysis is based on continuation methods, tracing out solution manifolds of various types of objects while some of the parameters of the map vary. In particular, MatContM computes codimension 1 bifurcation curves of cycles and supports the computation of the normal form coefficients of their codimension two bifurcations, and allows branch switching from codimension 2 points to secondary curves. MatContM builds on an earlier command-line MATLAB package CL MatContM but provides new computational routines and functionalities, as well as a graphical user interface, enabling interactive control of all computations, data handling and archiving. We apply MatContM in our study of the monopoly model of T. Puu with cubic price and quadratic marginal cost functions. Using MatContM, we analyze the fixed points and their stability and we compute branches of solutions of period 5, 10, 13 17. The chaotic and periodic behavior of the monopoly model is further analyzed by computing the largest Lyapunov exponents.

  19. Global genetic variation at OAS1 provides evidence of archaic admixture in Melanesian populations.

    PubMed

    Mendez, Fernando L; Watkins, Joseph C; Hammer, Michael F

    2012-06-01

    Recent analysis of DNA extracted from two Eurasian forms of archaic human shows that more genetic variants are shared with humans currently living in Eurasia than with anatomically modern humans in sub-Saharan Africa. Although these genome-wide average measures of genetic similarity are consistent with the hypothesis of archaic admixture in Eurasia, analyses of individual loci exhibiting the signal of archaic introgression are needed to test alternative hypotheses and investigate the admixture process. Here, we provide a detailed sequence analysis of the innate immune gene OAS1, a locus with a divergent Melanesian haplotype that is very similar to the Denisova sequence from the Altai region of Siberia. We resequenced a 7-kb region encompassing the OAS1 gene in 88 individuals from six Old World populations (San, Biaka, Mandenka, French Basque, Han Chinese, and Papua New Guineans) and discovered previously unknown and ancient genetic variation. The 5' region of this gene has unusual patterns of diversity, including 1) higher levels of nucleotide diversity in Papuans than in sub-Saharan Africans, 2) very deep ancestry with an estimated time to the most recent common ancestor of >3 myr, and 3) a basal branching pattern with Papuan individuals on either side of the rooted network. A global geographic survey of >1,500 individuals showed that the divergent Papuan haplotype is nearly restricted to populations from eastern Indonesia and Melanesia. Polymorphic sites within this haplotype are shared with the draft Denisova genome over a span of ∼90 kb and are associated with an extended block of linkage disequilibrium, supporting the hypothesis that this haplotype introgressed from an archaic source that likely lived in Eurasia.

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

    PubMed

    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.

  1. Genetic admixture, relatedness, and structure patterns among Mexican populations revealed by the Y-chromosome.

    PubMed

    Rangel-Villalobos, H; Muñoz-Valle, J F; González-Martín, A; Gorostiza, A; Magaña, M T; Páez-Riberos, L A

    2008-04-01

    Y-linked markers are suitable loci to analyze genetic diversity of human populations, offering knowledge of medical, forensic, and anthropological interest. In a population sample of 206 Mestizo males from western Mexico, we analyzed two binary loci (M3 and YAP) and six Y-STRs, adding to the analysis data of Mexican Mestizos and Amerindians, and relevant worldwide populations. The paternal ancestry estimated in western Mexican-Mestizos was mainly European (60-64%), followed by Amerindian (25-21%), and African ( approximately 15%). Significant genetic heterogeneity was established between Mestizos from western (Jalisco State) and northern Mexico (Chihuahua State) compared with Mexicans from the center of the Mexican Republic (Mexico City), this attributable to higher European ancestry in western and northern than in central and southeast populations, where higher Amerindian ancestry was inferred. This genetic structure has important implications for medical and forensic purposes. Two different Pre-Hispanic evolutionary processes were evident. In Mesoamerican region, populations presented higher migration rate (N(m) = 24.76), promoting genetic homogeneity. Conversely, isolated groups from the mountains and canyons of the Western and Northern Sierra Madre (Huichols and Tarahumaras, respectively) presented a lower migration rate (N(m) = 10.27) and stronger genetic differentiation processes (founder effect and/or genetic drift), constituting a Pre-Hispanic population substructure. Additionally, Tarahumaras presented a higher frequency of Y-chromosomes without Q3 that was explained by paternal European admixture (15%) and, more interestingly, by a distinctive Native-American ancestry. In Purepechas, a special admixture process involving preferential integration of non-Purepecha women in their communities could explain contrary genetic evidences (autosomal vs. Y-chromosome) for this tribe.

  2. Spectral density mapping at multiple magnetic fields suitable for 13C NMR relaxation studies

    NASA Astrophysics Data System (ADS)

    Kadeřávek, Pavel; Zapletal, Vojtěch; Fiala, Radovan; Srb, Pavel; Padrta, Petr; Přecechtělová, Jana Pavlíková; Šoltésová, Mária; Kowalewski, Jozef; Widmalm, Göran; Chmelík, Josef; Sklenář, Vladimír; Žídek, Lukáš

    2016-05-01

    Standard spectral density mapping protocols, well suited for the analysis of 15N relaxation rates, introduce significant systematic errors when applied to 13C relaxation data, especially if the dynamics is dominated by motions with short correlation times (small molecules, dynamic residues of macromolecules). A possibility to improve the accuracy by employing cross-correlated relaxation rates and on measurements taken at several magnetic fields has been examined. A suite of protocols for analyzing such data has been developed and their performance tested. Applicability of the proposed protocols is documented in two case studies, spectral density mapping of a uniformly labeled RNA hairpin and of a selectively labeled disaccharide exhibiting highly anisotropic tumbling. Combination of auto- and cross-correlated relaxation data acquired at three magnetic fields was applied in the former case in order to separate effects of fast motions and conformational or chemical exchange. An approach using auto-correlated relaxation rates acquired at five magnetic fields, applicable to anisotropically moving molecules, was used in the latter case. The results were compared with a more advanced analysis of data obtained by interpolation of auto-correlated relaxation rates measured at seven magnetic fields, and with the spectral density mapping of cross-correlated relaxation rates. The results showed that sufficiently accurate values of auto- and cross-correlated spectral density functions at zero and 13C frequencies can be obtained from data acquired at three magnetic fields for uniformly 13C -labeled molecules with a moderate anisotropy of the rotational diffusion tensor. Analysis of auto-correlated relaxation rates at five magnetic fields represents an alternative for molecules undergoing highly anisotropic motions.

  3. Resistance to Colletotrichum lindemuthianum in Phaseolus vulgaris: a case study for mapping two independent genes.

    PubMed

    Geffroy, Valérie; Sévignac, Mireille; Billant, Paul; Dron, Michel; Langin, Thierry

    2008-02-01

    Anthracnose, caused by the hemibiotrophic fungal pathogen Colletotrichum lindemuthianum is a devastating disease of common bean. Resistant cultivars are economical means for defense against this pathogen. In the present study, we mapped resistance specificities against 7 C. lindemuthianum strains of various geographical origins revealing differential reactions on BAT93 and JaloEEP558, two parents of a recombinant inbred lines (RILs) population, of Meso-american and Andean origin, respectively. Six strains revealed the segregation of two independent resistance genes. A specific numerical code calculating the LOD score in the case of two independent segregating genes (i.e. genes with duplicate effects) in a RILs population was developed in order to provide a recombination value (r) between each of the two resistance genes and the tested marker. We mapped two closely linked Andean resistance genes (Co-x, Co-w) at the end of linkage group (LG) B1 and mapped one Meso-american resistance genes (Co-u) at the end of LG B2. We also confirmed the complexity of the previously identified B4 resistance gene cluster, because four of the seven tested strains revealed a resistance specificity near Co-y from JaloEEP558 and two strains identified a resistance specificity near Co-9 from BAT93. Resistance genes found within the same cluster confer resistance to different strains of a single pathogen such as the two anthracnose specificities Co-x and Co-w clustered at the end of LG B1. Clustering of resistance specificities to multiple pathogens such as fungi (Co-u) and viruses (I) was also observed at the end of LG B2.

  4. AVIRIS Land-Surface Mapping in Support of the Boreal Ecosystem-Atmosphere Study (BOREAS)

    NASA Technical Reports Server (NTRS)

    Roberts, Dar A.; Gamon, John; Keightley, Keir; Prentiss, Dylan; Reith, Ernest; Green, Robert

    2001-01-01

    A key scientific objective of the original Boreal Ecosystem-Atmospheric Study (BOREAS) field campaign (1993-1996) was to obtain the baseline data required for modeling and predicting fluxes of energy, mass, and trace gases in the boreal forest biome. These data sets are necessary to determine the sensitivity of the boreal forest biome to potential climatic changes and potential biophysical feedbacks on climate. A considerable volume of remotely-sensed and supporting field data were acquired by numerous researchers to meet this objective. By design, remote sensing and modeling were considered critical components for scaling efforts, extending point measurements from flux towers and field sites over larger spatial and longer temporal scales. A major focus of the BOREAS follow-on program is concerned with integrating the diverse remotely sensed and ground-based data sets to address specific questions such as carbon dynamics at local to regional scales. The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) has the potential of contributing to BOREAS through: (1) accurate retrieved apparent surface reflectance; (2) improved landcover classification; and (3) direct assessment of biochemical/biophysical information such as canopy liquid water and chlorophyll concentration through pigment fits. In this paper, we present initial products for major flux tower sites including: (1) surface reflectance of dominant cover types; (2) a land-cover classification developed using spectral mixture analysis (SMA) and Multiple Endmember Spectral Mixture Analysis (MESMA); and (3) liquid water maps. Our goal is to compare these land-cover maps to existing maps and to incorporate AVIRIS image products into models of photosynthetic flux.

  5. Geospatial modelling for groundwater quality mapping: a case study of Rupnagar district, Punjab, India

    NASA Astrophysics Data System (ADS)

    Sahoo, S.; Kaur, A.; Litoria, P.; Pateriya, B.

    2014-11-01

    Over period of time, the water usage and management is under stress for various reasons including pollution in both surface and subsurface. The groundwater quality decreases due to the solid waste from urban and industrial nodes, rapid use of insecticides and pesticides in agricultural practices. In this study, ground water quality maps for Rupnagar district of Punjab has been prepared using geospatial interpolation technique through Inverse Distance Weighted (IDW) approach. IDW technique has been used for major ground water quality parameters observed from the field samples like Arsenic, Hardness, pH, Iron, Fluoride, TDS, and Sulphate. To assess the ground water quality of the Rupnagar district, total 280 numbers of samples from various sources of tubewells for both pre and post monsoon have collected. Out of which, 80 to 113 samples found Iron with non potable limits ranging 0.3-1.1mg/l and 0.3-1.02mg/l according to BIS standard for both the seasons respectively. Chamkaur Sahib, Rupnagar, Morinda blocks have been found non potable limit of iron in both pre & post-monsoon. 11 to 52 samples in this region have sulphate with permissible limits in both the season ranging 200-400mg/l and 201-400mg/l. But arsenic had acceptable limit in both the season. Various parameters-wise ground water quality map is generated using the range values of drinking water quality to know the distribution of different parameters and diversification in the concentration of different elements. These maps are very much needful for human being to expand awareness among the people to maintain the Cleanness of water at their highest quality and purity levels to achieve a healthy life.

  6. Body fat and racial genetic admixture are associated with aerobic fitness levels in a multiethnic pediatric population.

    PubMed

    Willig, Amanda L; Hunter, Gary R; Casazza, Krista; Heimburger, Douglas C; Beasley, T Mark; Fernandez, Jose R

    2011-11-01

    Aerobic fitness and adiposity are each independently associated with health outcomes among children, although the relationship between these two variables is unclear. Our objectives were to evaluate (i) the association of adiposity with aerobic fitness using objectively measured levels of percent body fat, compared to BMI as a percentile proxy for adiposity while controlling for genetic admixture, and (ii) the congruence of BMI categories with high and low body fat categories of objectively measured percent body fat. Participants were 232 African-American (AA), European-American (EA), and Hispanic-American (HA) children aged 7-12 years (Tanner stage <3). Aerobic fitness was measured via a submaximal indirect calorimetry treadmill test (VO(2-170)), and physical activity levels with accelerometry. Genetic admixture estimates were obtained using 140 genetic ancestry informative markers to estimate European, African, and Amerindian admixture. Fat mass was determined using dual-energy x-ray absorptiometry (DXA). Children were classified into a low body fat group (<25% in males, <30% in females) or a high body fat group based on their percent body fat; children were also categorized according to BMI percentile. Children in the low body fat group had significantly higher aerobic fitness (P < 0.05) regardless of BMI percentile classification. Higher African genetic admixture was associated with lower aerobic fitness (P < 0.05), while physical activity was positively associated with fitness (P < 0.01). In conclusion, aerobic fitness levels differ by percent body fat and genetic admixture irrespective of BMI classification, and such differences should be taken into account when evaluating outcomes of health interventions.

  7. Geospatial approach in mapping soil erodibility using CartoDEM - A case study in hilly watershed of Lower Himalayan Range

    NASA Astrophysics Data System (ADS)

    Kumar, Suresh; Gupta, Surya

    2016-10-01

    Soil erodibility is one of the most important factors used in spatial soil erosion risk assessment. Soil information derived from soil map is used to generate soil erodibility factor map. Soil maps are not available at appropriate scale. In general, soil maps at small scale are used in deriving soil erodibility map that largely generalized spatial variability and it largely ignores the spatial variability since soil map units are discrete polygons. The present study was attempted to generate soil erodibilty map using terrain indices derived from DTM and surface soil sample data. Soil variability in the hilly landscape is largely controlled by topography represented by DTM. The CartoDEM (30 m) was used to derive terrain indices such as terrain wetness index (TWI), stream power index (SPI), sediment transport index (STI) and slope parameters. A total of 95 surface soil samples were collected to compute soil erodibility factor ( K) values. The K values ranged from 0.23 to 0.81 t ha-1R-1 in the watershed. Correlation analysis among K-factor and terrain parameters showed highest correlation of soil erodibilty with TWI ( r 2= 0.561) followed by slope ( r 2= 0.33). A multiple linear regression model was developed to derive soil erodibilty using terrain parameters. A set of 20 soil sample points were used to assess the accuracy of the model. The coefficient of determination ( r 2) and RMSE were computed to be 0.76 and 0.07 t ha-1R-1 respectively. The proposed methodology is quite useful in generating soil erodibilty factor map using digital elevation model (DEM) for any hilly terrain areas. The equation/model need to be established for the particular hilly terrain under the study. The developed model was used to generate spatial soil erodibility factor ( K) map of the watershed in the lower Himalayan range.

  8. PETROLEUM RESIDUA SOLUBILITY PARAMETER/POLARITY MAP: STABILITY STUDIES OF RESIDUA PYROLYSIS

    SciTech Connect

    John F. Schabron; A. Troy Pauli; Joseph F. Rovani, Jr.

    1999-04-30

    A new molecular weight/polarity map based on the Scatchard-Hildebrand solubility equation has been developed for petroleum residua. A series of extractions are performed with solvents of increasing solubility parameter, and the fractions are analyzed by vapor pressure osmometry for number average molecular weight and by analytical-scale size exclusion chromatography for molecular weight spread. Work was performed for a heavy oil material subjected to three increasing severities of thermal treatment prior to and through the onset of coke formation. The results are diagnostic of the layers of solvations by resin-type molecules around a central asphaltene core. Two additional stability diagnostic methods were also used. These were the Heithaus titration ''P-index'' and Gaestel ''G'' index, which have been applied to paving asphalts for decades. The Heithaus titration involves the titration of three toluene solutions of a residuum at three concentrations with a poor solvent, such as isooctane, to the point of asphaltene flocculation. In the present work, the significance of the data are developed in terms of the Hildebrand solubility parameter. The Heithaus results are combined with data from the new molecular weight/polarity map. The solubility parameters for the toluene-soluble asphaltene components are measured, and the solubility parameters of the maltenes can be calculated. As thermal treatment progresses, the solubility parameters of asphaltene materials increase and the molecular weights decrease. A new coking index is proposed based on Heithaus titration data. Preliminary results suggest that an alternative, simpler coking index may be developed by measuring the weight percent of cyclohexane solubles in heptane asphaltenes. Coking onset appears to coincide with the depletion of these resin-type asphaltene solubilizing co