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Sample records for crossing over genetic

  1. Genetic Background, Maternal Age, and Interaction Effects Mediate Rates of Crossing Over in Drosophila melanogaster Females.

    PubMed

    Hunter, Chad M; Robinson, Matthew C; Aylor, David L; Singh, Nadia D

    2016-01-01

    Meiotic recombination is a genetic process that is critical for proper chromosome segregation in many organisms. Despite being fundamental for organismal fitness, rates of crossing over vary greatly between taxa. Both genetic and environmental factors contribute to phenotypic variation in crossover frequency, as do genotype-environment interactions. Here, we test the hypothesis that maternal age influences rates of crossing over in a genotypic-specific manner. Using classical genetic techniques, we estimated rates of crossing over for individual Drosophila melanogaster females from five strains over their lifetime from a single mating event. We find that both age and genetic background significantly contribute to observed variation in recombination frequency, as do genotype-age interactions. We further find differences in the effect of age on recombination frequency in the two genomic regions surveyed. Our results highlight the complexity of recombination rate variation and reveal a new role of genotype by maternal age interactions in mediating recombination rate. PMID:26994290

  2. Genetic Background, Maternal Age, and Interaction Effects Mediate Rates of Crossing Over in Drosophila melanogaster Females

    PubMed Central

    Hunter, Chad M.; Robinson, Matthew C.; Aylor, David L.; Singh, Nadia D.

    2016-01-01

    Meiotic recombination is a genetic process that is critical for proper chromosome segregation in many organisms. Despite being fundamental for organismal fitness, rates of crossing over vary greatly between taxa. Both genetic and environmental factors contribute to phenotypic variation in crossover frequency, as do genotype–environment interactions. Here, we test the hypothesis that maternal age influences rates of crossing over in a genotypic-specific manner. Using classical genetic techniques, we estimated rates of crossing over for individual Drosophila melanogaster females from five strains over their lifetime from a single mating event. We find that both age and genetic background significantly contribute to observed variation in recombination frequency, as do genotype–age interactions. We further find differences in the effect of age on recombination frequency in the two genomic regions surveyed. Our results highlight the complexity of recombination rate variation and reveal a new role of genotype by maternal age interactions in mediating recombination rate. PMID:26994290

  3. [Unequal crossing over in Escherichia coli: genetic and physical mapping of duplications isolated in conjugational matings].

    PubMed

    Sukhodolets, V V; Dukhiĭ, D E

    1996-01-01

    We previously demonstrated that stable heterozygous duplications deoA deoB :: Tn5/deoC deoD can be isolated among Deo+ recombinants obtained in conjugational matings between Escherichia coli strains HfrH deoA deoB :: Tn5 and HfrH deoC deoD. In this work, 30 duplications were tested by transduction for the inclusion of a set of genetic markers adjoining the deo operon (99.5 min) at the genetic map of E. coli: cycA :: Tn10 (96 min), zji :: Tn10 (98.2 min), thr :: Tn9 (100/0 min), car :: Tn10 (1 min), leu :: Tn9 (2 min), and proAB :: Tn10 (6 min). The results obtained indicate that only three out of 30 duplications could have originated from unequal crossing over between the rrn operons. In eight strains, duplications were chosen for physical mapping by the use of Not I restriction, pulsed-field electrophoresis, and Southern blot hybridization with DNA of the deo operon. In all these strains, the presence of duplications (once a triplication) was confirmed by corresponding changes in the set of Not I digests, although some strains had additional genetic rearrangements. The order of operon copies in a tandem was determined, and the length of a duplicated chromosomal segment was calculated as equal to 25, 46, 80, 150.5, and 175 kb in duplication D49, D4, D5, D9, and D18, respectively. Thus, the use of the conjugational Hfr x Hfr system allows the generation of unique rearrangements of the E. coli genetic material. PMID:8647423

  4. Unequal Crossing over at the Rrna Tandon as a Source of Quantitative Genetic Variation in Drosophila

    PubMed Central

    Frankham, R.; Briscoe, D. A.; Nurthen, R. K.

    1980-01-01

    Abdominal bristle selection lines (three high and three low) and controls were founded from a marked homozygous line to measure the contribution of sex-linked "mutations" to selection response. Two of the low lines exhibited a period of rapid response to selection in females, but not in males. There were corresponding changes in female variance, in heritabilities in females, in the sex ratio (a deficiency of females) and in fitness, as well as the appearance of a mutant phenotype in females of one line. All of these changes were due to bb alleles (partial deficiencies for the rRNA tandon) in the X chromosomes of these lines, while the Y chromosomes remained wild-type bb+. We argue that the bb alleles arose by unequal crossing over in the rRNA tandon.—A prediction of this hypothesis is that further changes can occur in the rRNA tandon as selection is continued. This has now been shown to occur.—Our minimum estimate of the rate of occurrence of changes at the rRNA tandon is 3 x 10-4. As this is substantially higher than conventional mutation rates, the questions of the mechanisms and rates of origin of new quantitative genetic variation require careful re-examination. PMID:7439683

  5. How are parent-child conflict and childhood externalizing symptoms related over time? Results from a genetically informative cross-lagged study.

    PubMed

    Burt, S Alexandra; McGue, Matt; Krueger, Robert F; Iacono, William G

    2005-01-01

    The present study attempted to determine the direction and etiology of the robust relationship between childhood externalizing (EXT) symptoms and parent-child conflict using a genetically informative longitudinal model and data from the ongoing Minnesota Twin Family Study. Participants consisted of 1,506 same-sex twins assessed at ages 11 and 14, and their parents. The relationship between EXT and parent-child conflict from ages 11 to 14 was examined within a biometrical cross-lagged design. The results revealed three primary findings: first, the stability of conflict and externalizing over time is largely, although not solely, a result of genetic factors. Second, there appears to be a bidirectional relationship between conflict and EXT over time, such that both conflict and EXT at 11 independently predict the other 3 years later. Finally, the results are consistent with the notion that parent-child conflict partially results from parental responses to their child's heritable externalizing behavior, while simultaneously contributing to child externalizing via environmental mechanisms. These results suggest a "downward spiral" of interplay between parent-child conflict and EXT, and offer confirmation of a (partially) environmentally mediated effect of parenting on child behavior. PMID:15971764

  6. A novel approach to genetic and environmental analysis of cross-lagged associations over time: the cross-lagged relationship between self-perceived abilities and school achievement is mediated by genes as well as the environment.

    PubMed

    Luo, Yu L L; Haworth, Claire M A; Plomin, Robert

    2010-10-01

    Using longitudinal cross-lagged analysis to infer causal directions of reciprocal effects is one of the most important tools in the developmental armamentarium. The strength of these analyses can be enhanced by analyzing the genetic and environmental aetiology underlying cross-lagged relationships, for which we present a novel approach here. Our approach is based on standard Cholesky decomposition. Standardized path coefficients are employed to assess genetic and environmental contributions to cross-lagged associations. We indicate how our model differs importantly from another approach that does not in fact analyze genetic and environmental contributions to cross-lagged associations. As an illustration, we apply our approach to the analysis of the cross-lagged relationships between self-perceived abilities and school achievement from age 9 to age 12. Self-perceived abilities of 3852 pairs of twins from the UK Twins Early Development Study were assessed using a self-report scale. School achievement was assessed by teachers based on UK National Curriculum criteria. The key cross-lagged association between self-perceived abilities at age 9 and school achievement at age 12 was mediated by genetic influences (28%) as well as shared (55%) and non-shared (16%) environment. The reverse cross-lagged association from school achievement at 9 to self-perceived abilities at 12 was primarily genetically mediated (73%). Unlike the approach to cross-lagged genetic analysis used in recent research, our approach assesses genetic and environmental contributions to cross-lagged associations per se. We discuss implications of finding that genetic factors contribute to the cross-lag between self-perceived abilities at age 9 and school achievement at age 12. PMID:20874463

  7. Bridge over Troubled Water: Guidance Crosses

    ERIC Educational Resources Information Center

    Amundson, Norm

    2008-01-01

    This article is based on a keynote presentation at an international conference where the focus was cross-over career guidance. Simon and Garfunkel's popular song, "Bridge over troubled water", was used as a metaphor for exploring the cross-over theme. Some of the concepts under consideration included the working alliance, the importance of a…

  8. Genetic Diversity in Cotton Out-Crossing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previously we have reported on the finding of genetic differences in the abiotic stress tolerance of cotton pollen. Genetic differences in sensitivity to humidity were observed impacting pollen survival in dry environments. The present study evaluated out-crossing rates in cotton lines whose polle...

  9. Cedarwood: cross-over pressure research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A series of experiments were conducted to determine the cross-over pressure for cedarwood oil in carbon dioxide. A closed stirrer reactor with an in-line loop connected to the injector of a GC was used to measure the concentration of cedarwood oil in the carbon dioxide. Both neat cedarwood oil as ...

  10. Genetic control over the resting brain

    PubMed Central

    Glahn, D. C.; Winkler, A. M.; Kochunov, P.; Almasy, L.; Duggirala, R.; Carless, M. A.; Curran, J. C.; Olvera, R. L.; Laird, A. R.; Smith, S. M.; Beckmann, C. F.; Fox, P. T.; Blangero, J.

    2010-01-01

    The default-mode network, a coherent resting-state brain network, is thought to characterize basal neural activity. Aberrant default-mode connectivity has been reported in a host of neurological and psychiatric illnesses and in persons at genetic risk for such illnesses. Whereas the neurophysiologic mechanisms that regulate default-mode connectivity are unclear, there is growing evidence that genetic factors play a role. In this report, we estimate the importance of genetic effects on the default-mode network by examining covariation patterns in functional connectivity among 333 individuals from 29 randomly selected extended pedigrees. Heritability for default-mode functional connectivity was 0.424 ± 0.17 (P = 0.0046). Although neuroanatomic variation in this network was also heritable, the genetic factors that influence default-mode functional connectivity and gray-matter density seem to be distinct, suggesting that unique genes influence the structure and function of the network. In contrast, significant genetic correlations between regions within the network provide evidence that the same genetic factors contribute to variation in functional connectivity throughout the default mode. Specifically, the left parahippocampal region was genetically correlated with all other network regions. In addition, the posterior cingulate/precuneus region, medial prefrontal cortex, and right cerebellum seem to form a subnetwork. Default-mode functional connectivity is influenced by genetic factors that cannot be attributed to anatomic variation or a single region within the network. By establishing the heritability of default-mode functional connectivity, this experiment provides the obligatory evidence required before these measures can be considered as endophenotypes for psychiatric or neurological illnesses or to identify genes influencing intrinsic brain function. PMID:20133824

  11. French Crossings: II. Laughing Over Boundaries

    PubMed Central

    Jones, Colin

    2016-01-01

    Under the generic title, ‘French Crossings’, this Presidential Address explores the history of laughter in French society, and humour’s potential for trangressing boundaries. It focuses on the irreverent and almost entirely unknown book of comic drawings entitled Livre de caricatures tant Bonnes que mauvaises (Book of Caricatures, both Good and Bad), that was composed between the 1740s and the mid-1770s by the luxury Parisian embroiderer and designer, Charles-Germain de Saint-Aubin, and his friends and family. The bawdy laughter that the book seems intended to provoke gave it its nickname of the Livre de culs (Book of Arses). Yet despite the scatological character of many of the drawings, the humour often conjoined lower body functions with rather cerebral and erudite wit. The laughter provoked unsparingly targeted and exposed to ridicule the social elite, cultural celebrities and political leaders of Ancien Regime France. This made it a dangerous object, which was kept strictly secret. Was this humour somehow pre- or proto-Revolutionary? In fact, the work is so embedded in the culture of the Ancien Regime that 1789 was one boundary that the work signally fails to cross.

  12. Standard model cross-over on the lattice

    NASA Astrophysics Data System (ADS)

    D'Onofrio, Michela; Rummukainen, Kari

    2016-01-01

    With the physical Higgs mass the standard model symmetry restoration phase transition is a smooth cross-over. We study the thermodynamics of the cross-over using numerical lattice Monte Carlo simulations of an effective SU (2 )×U (1 ) gauge+Higgs theory, significantly improving on previously published results. We measure the Higgs field expectation value, thermodynamic quantities like pressure, energy density, speed of sound and heat capacity, and screening masses associated with the Higgs and Z fields. While the cross-over is smooth, it is very well defined with a width of only ˜5 GeV . We measure the cross-over temperature from the maximum of the susceptibility of the Higgs condensate, with the result Tc=159.5 ±1.5 GeV . Outside of the narrow cross-over region the perturbative results agree well with nonperturbative ones.

  13. DNA repair and crossing over favor similar chromosome regions as discovered in radiation hybrid of Triticum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The uneven distribution of recombination across the length of chromosomes results in inaccurate estimates of genetic to physical distances. In wheat (Triticum aestivum L.) chromosome 3B, it has been estimated that 90% of the cross over occurs in distal sub-telomeric regions representing 40% of the...

  14. View of Steel Flume Bridge #2 crossing over wash. Looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Steel Flume Bridge #2 crossing over wash. Looking downstream, southwest - Childs-Irving Hydroelectric Project, Childs System, Flume Bridge No. 2, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  15. View of Steel Flume Bridge #3 crossing over Sally May ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Steel Flume Bridge #3 crossing over Sally May Wash. Looking northwest - Childs-Irving Hydroelectric Project, Childs System, Flume Bridge No. 3, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  16. 4. END OF RAILWAY SUPERSTRUCTURE, WHERE IT CROSSES NORTH OVER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. END OF RAILWAY SUPERSTRUCTURE, WHERE IT CROSSES NORTH OVER MARKET STREET AND DESCENDS TO MEET SUBWAY AT 44TH STREET. - Market Street Elevated Railway, Market Street between Sixty-ninth & Forty-sixth Streets, Philadelphia, Philadelphia County, PA

  17. Genetic Crossing vs Cloning by Computer Simulation

    NASA Astrophysics Data System (ADS)

    Dasgupta, Subinay

    We perform Monte Carlo simulation using Penna's bit string model, and compare the process of asexual reproduction by cloning with that by genetic crossover. We find them to be comparable as regards survival of a species, and also if a natural disaster is simulated.

  18. Genetic crossing vs cloning by computer simulation

    SciTech Connect

    Dasgupta, S.

    1997-06-01

    We perform Monte Carlo simulation using Penna`s bit string model, and compare the process of asexual reproduction by cloning with that by genetic crossover. We find them to be comparable as regards survival of a species, and also if a natural disaster is simulated.

  19. Genetic Diversity of Natural Crossing in Cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have shown previously genetic diversity in mature cotton pollen sensitivity to low humidity. This study investigated the impact of pollen sensitivity to low humidity on the amount of outcrossing to neighboring plants. We utilized “red” and “green” pigmented cotton, in addition to gossypol glan...

  20. Plasmodium falciparum genetic crosses in a humanized mouse model

    PubMed Central

    Vaughan, Ashley M.; Pinapati, Richard S.; Cheeseman, Ian H.; Camargo, Nelly; Fishbaugher, Matthew; Checkley, Lisa A.; Nair, Shalini; Hutyra, Carolyn A.; Nosten, François H.; Anderson, Timothy J. C.; Ferdig, Michael T.; Kappe, Stefan H. I.

    2015-01-01

    Genetic crosses of phenotypically distinct strains of the human malaria parasite Plasmodium falciparum are a powerful tool for identifying genes controlling drug resistance and other key phenotypes. Previous studies relied on the isolation of recombinant parasites from splenectomized chimpanzees, a research avenue that is no longer available. Here, we demonstrate that human-liver chimeric mice support recovery of recombinant progeny for the identification of genetic determinants of parasite traits and adaptations. PMID:26030447

  1. A genetic algorithm to reduce stream channel cross section data

    USGS Publications Warehouse

    Berenbrock, C.

    2006-01-01

    A genetic algorithm (GA) was used to reduce cross section data for a hypothetical example consisting of 41 data points and for 10 cross sections on the Kootenai River. The number of data points for the Kootenai River cross sections ranged from about 500 to more than 2,500. The GA was applied to reduce the number of data points to a manageable dataset because most models and other software require fewer than 100 data points for management, manipulation, and analysis. Results indicated that the program successfully reduced the data. Fitness values from the genetic algorithm were lower (better) than those in a previous study that used standard procedures of reducing the cross section data. On average, fitnesses were 29 percent lower, and several were about 50 percent lower. Results also showed that cross sections produced by the genetic algorithm were representative of the original section and that near-optimal results could be obtained in a single run, even for large problems. Other data also can be reduced in a method similar to that for cross section data.

  2. A teaching framework for cross-cultural genetic counseling.

    PubMed

    Weil, J; Mittman, I

    1993-09-01

    The increasing diversity of American society has brought growing recognition of the need to bridge cultures in the delivery of genetic counseling services. New immigrants and members of diverse ethnic groups face multiple barriers to genetic counseling services. The need to train genetic counselors to deal with cultural diversity is especially crucial in the new genetic era, given the rapid expansion of available technology, with the resulting social and ethical ramifications. A framework for teaching cross-cultural issues in genetic counseling training programs is presented that can be implemented in step-wise fashion, consistent with available resources. Cross-cultural issues can be incorporated into existing teaching and training modalities by expanding the orientation from monocultural to multicultural. Relevant clinical experience, exploration of students' preconceptions and biases, reading materials, and lectures by invited speakers can all enhance students' knowledge and sensitivity. It is critically important that training programs furnish students with the basic tools necessary for the ongoing process of learning about cultural diversity. PMID:24242637

  3. Mutagenesis and interchromosomal effect on crossing-over in Drosophila

    SciTech Connect

    Chadov, B.F.; Chadova, E.V.

    1994-12-01

    The possibility of mutational consequences of interchromosomal effect on crossing-over was studied in Drosophila melanogaster females with four genotypes: (1) structurally normal (control); (2) heterozygous at In(1)Muller-5 inversion (X chromosome); (3) heterozygous at In(3LR)CxD inversion (chromosome 3); and (4) heterozygous at both inversions. The mutational effect was determined through the loss of autosome 2 and formation of arm compounds C(2L) and C(2R). In females with recombinations, the rate of mutational events did not exceed that of the control. It was concluded that interchromosomal effect on crossing-over is of a regulatory character and disturbs neither recombination itself nor chromosome pairing. Coorientation X-3 leading to the appearance of intersexes in the progeny occurred in meiosis in females with two inversions.

  4. The evolutionary stability of cross-sex, cross-trait genetic covariances.

    PubMed

    Gosden, Thomas P; Chenoweth, Stephen F

    2014-06-01

    Although knowledge of the selective agents behind the evolution of sexual dimorphism has advanced considerably in recent years, we still lack a clear understanding of the evolutionary durability of cross-sex genetic covariances that often constrain its evolution. We tested the relative stability of cross-sex genetic covariances for a suite of homologous contact pheromones of the fruit fly Drosophila serrata, along a latitudinal gradient where these traits have diverged in mean. Using a Bayesian framework, which allowed us to account for uncertainty in all parameter estimates, we compared divergence in the total amount and orientation of genetic variance across populations, finding divergence in orientation but not total variance. We then statistically compared orientation divergence of within-sex (G) to cross-sex (B) covariance matrices. In line with a previous theoretical prediction, we find that the cross-sex covariance matrix, B, is more variable than either within-sex G matrix. Decomposition of B matrices into their symmetrical and nonsymmetrical components revealed that instability is linked to the degree of asymmetry. We also find that the degree of asymmetry correlates with latitude suggesting a role for spatially varying natural selection in shaping genetic constraints on the evolution of sexual dimorphism. PMID:24620712

  5. The Use and Reporting of the Cross-Over Study Design in Clinical Trials and Systematic Reviews: A Systematic Assessment

    PubMed Central

    Hambleton, Ian; Dwan, Kerry

    2016-01-01

    Background Systematic reviews of treatment interventions in stable or chronic conditions often require the synthesis of clinical trials with a cross-over design. Previous work has indicated that methodology for analysing cross-over data is inadequate in trial reports and in systematic reviews assessing trials with this design. Objective We assessed systematic review methodology for synthesising cross-over trials among Cochrane Cystic Fibrosis and Genetic Disorders Group reviews published to July 2015, and assessed the quality of reporting among the cross-over trials included in these reviews. Methodology We performed data extraction of methodology and reporting in reviews, trials identified and trials included within reviews. Principal Findings We reviewed a total of 142 Cochrane systematic reviews including 53 reviews which synthesised evidence from 218 cross-over trials. Thirty-three (63%) Cochrane reviews described a clear and appropriate method for the inclusion of cross-over data, and of these 19 (56%) used the same method to analyse results. 145 cross-over trials were described narratively or treated as parallel trials in reviews but in 30 (21%) of these trials data existed in the trial reports to account for the cross-over design. At the trial level, the analysis and presentation of results were often inappropriate or unclear, with only 69 (32%) trials presenting results that could be included in meta-analysis. Conclusions Despite development of accessible, technical guidance and training for Cochrane systematic reviewers, statistical analysis and reporting of cross-over data is inadequate at both the systematic review and the trial level. Plain language and practical guidance for the inclusion of cross-over data in meta-analysis would benefit systematic reviewers, who come from a wide range of health specialties. Minimum reporting standards for cross-over trials are needed. PMID:27409076

  6. Genetic analysis in the Collaborative Cross breeding population

    SciTech Connect

    Philip, Vivek; Sokoloff, Greta; Ackert-Bicknell, Cheryl; Striz, Martin; Branstetter, Lisa R; Beckmann, Melissa; Spence, Jason S; Jackson, Barbara L; Galloway, Leslie D; Barker, Gene; Wymore, Ann M; Hunsicker, Patricia R; Durtschi, David W; Shaw, Ginger S; Shinpock, Sarah G; Manly, Kenneth F; Miller, Darla R; Donahue, Kevin; Culiat, Cymbeline T; Churchill, Gary A; Lariviere, William R; Palmer, Abraham; O'Hara, Bruce; Voy, Brynn H; Chesler, Elissa J

    2011-01-01

    Genetic reference populations in model organisms are critical resources for systems genetic analysis of disease related phenotypes. The breeding history of these inbred panels may influence detectable allelic and phenotypic diversity. The existing panel of common inbred strains reflects historical selection biases, and existing recombinant inbred panels have low allelic diversity. All such populations may be subject to consequences of inbreeding depression. The Collaborative Cross (CC) is a mouse reference population with high allelic diversity that is being constructed using a randomized breeding design that systematically outcrosses eight founder strains, followed by inbreeding to obtain new recombinant inbred strains. Five of the eight founders are common laboratory strains, and three are wild-derived. Since its inception, the partially inbred CC has been characterized for physiological, morphological, and behavioral traits. The construction of this population provided a unique opportunity to observe phenotypic variation as new allelic combinations arose through intercrossing and inbreeding to create new stable genetic combinations. Processes including inbreeding depression and its impact on allelic and phenotypic diversity were assessed. Phenotypic variation in the CC breeding population exceeds that of existing mouse genetic reference populations due to both high founder genetic diversity and novel epistatic combinations. However, some focal evidence of allele purging was detected including a suggestive QTL for litter size in a location of changing allele frequency. Despite these inescapable pressures, high diversity and precision for genetic mapping remain. These results demonstrate the potential of the CC population once completed and highlight implications for development of related populations. Supplementary material consists of Supplementary Table 1 Phenotypic means, variances, ranges and heritabilities for all traits and generations, Supplementary Table

  7. Internal tidal currents over the summit of cross seamount

    USGS Publications Warehouse

    Noble, M.; Mullineaux, L.S.

    1989-01-01

    Spectral analysis of 46 days of record from a current meter deployed above the summit of Cross Seamount (approximately 300 km west of the Hawaiian Islands) indicates that the strongest current fluctuations were driven by the semidiurnal tide. The tides accounted for 28% of the variance in the current spectrum, were mainly baroclinic in character, and were propagated towards the west-northwest. The amplitude of the S2 current flowing parallel to the major axis of the current ellipse ranged between 4 and 9 cm-1 s. The S2 current was 1.5 times larger than the M2 current. This ratio is 4 times larger than is expected for this region of the Pacific and is not a general characteristics of flows over seamounts. Instantaneous current speeds over the seamount often exceeded 20 cm s-1 and were probably responsible for the small ripples observed on the sediment-covered regions of the summit. ?? 1990.

  8. Keel petal incision: a simple and efficient method for genetic crossing in Medicago truncatula

    PubMed Central

    2014-01-01

    Background Genetic crossing is an essential tool in both forward and reverse genetic approaches to understand the biological functions of genes. For Medicago truncatula (barrel medic) various crossing techniques have been used which differ in the methods used to dissect the female parent’s unopened flower bud to remove immature anthers for prevention of self-pollination. Previously described methods including front, side or back incision methods may damage the flower bud, impeding successful fertilization and/or seed development because they may allow pollen to dislodge and floral organs to desiccate after crossing, all of which diminish the success rates of crossing. Results We report the keel petal incision method for genetic crossing in M. truncatula ecotype R108 and demonstrate successful crosses with two other M. truncatula ecotypes, A17 and A20. In the method presented here, an incision is made along the central line of the keel petal from the bottom 1/3rd of the female parent’s flower bud to its distal end. This allows easy removal of anthers from the flower bud and access for cross-pollination. After pollination, the stigma and the deposited pollen from the male donor are covered by the keel petal, wing petals and standard petal, forming a natural pouch. The pouch prevents dislodging of deposited pollen from the stigma and protects the internal floral organs from drying out, without using cling-film or water-containing chambers to maintain a humid environment. The keel petal incision method showed an approximate 80% success rate in the M. truncatula R108 ecotype and also in other ecotypes including Jemalong A17 and A20. Conclusions Our keel petal incision protocol shows marked improvement over existing methods with respect to the ease of crossing and the percentage of successful crosses. Developed for the M. truncatula R108 ecotype, the protocol has been demonstrated with A17 and A20 ecotypes and is expected to work with other ecotypes. Investigators of

  9. Ploidy, sex and crossing over in an evolutionary aging model

    NASA Astrophysics Data System (ADS)

    Lobo, Matheus P.; Onody, Roberto N.

    2006-02-01

    Nowadays, many forms of reproduction coexist in nature: Asexual, sexual, apomictic and meiotic parthenogenesis, hermaphroditism and parasex. The mechanisms of their evolution and what made them successful reproductive alternatives are very challenging and debated questions. Here, using a simple evolutionary aging model, we give a possible scenario. By studying the performance of populations where individuals may have diverse characteristics-different ploidies, sex with or without crossing over, as well as the absence of sex-we find an evolution sequence that may explain why there are actually two major or leading groups: Sexual and asexual. We also investigate the dependence of these characteristics on different conditions of fertility and deleterious mutations. Finally, if the primeval organisms on Earth were, in fact, asexual individuals we conjecture that the sexual form of reproduction could have more easily been set and found its niche during a period of low-intensity mutations.

  10. Mutant Rec-1 Eliminates the Meiotic Pattern of Crossing over in Caenorhabditis Elegans

    PubMed Central

    Zetka, M. C.; Rose, A. M.

    1995-01-01

    Meiotic crossovers are not randomly distributed along the chromosome. In Caenorhabditis elegans the central portions of the autosomes have relatively few crossovers compared to the flanking regions. We have measured the frequency of crossing over for several intervals across chromosome I in strains mutant for rec-1. The chromosome is ~50 map units in both wild-type and rec-1 homozygotes, however, the distribution of exchanges is very different in rec-1. Map distances expand across the gene cluster and contract near the right end of the chromosome, resulting in a genetic map more consistent with the physical map. Mutations in two other genes, him-6 and him-14, also disrupted the distribution of exchanges. Unlike rec-1, individuals homozygous for him-6 and him-14 had an overall reduction in the amount of crossing over accompanied by a high frequency of nondisjunction and reduced egg hatching. In rec-1; him-6 and rec-1; him-14 homozygotes the frequency of crossing over was characteristic of the Him mutant phenotype, whereas the distribution of the reduced number of exchanges was characteristic of the Rec-1 pattern. It appears that these gene products play a role in establishing the meiotic pattern of exchange events. PMID:8601478

  11. The Collaborative Cross at Oak Ridge National Laboratory: developing a powerful resource for systems genetics

    SciTech Connect

    Chesler, Elissa J; Branstetter, Lisa R; Churchill, Gary A; Culiat, Cymbeline T; Galloway, Leslie D; Jackson, Barbara L; Johnson, Dabney K; Miller, Darla R; Philip, Vivek M; Threadgill, David; Voy, Brynn H; Williams, Robert; Manly, Kenneth

    2008-01-01

    Complex traits and disease co-morbidity in humans and in model organisms are the result of naturally occurring polymorphisms that interact with each other and with the environment. To ensure the availability of the resources needed to investigate biomolecular networks and ultimately systems level phenotypes, we have initiated breeding of a new genetic reference population of mice, the Collaborative Cross. This population has been designed to optimally support systems genetics analysis. Its novel and important features include high levels of genetic diversity, a large population size to ensure sufficient power in high-dimensional studies, and high mapping precision through accumulation of independent recombination events. Implementation of the Collaborative Cross has been in progress at the Oak Ridge National Laboratory (ORNL) since May 2005. This is achieved through a software assisted breeding program with fully traceable lineages, performed in a uniform environment. Currently, there are 650 lines in production with almost 200 lines over seven generations of inbreeding. Retired breeders enter a high-throughput phenotyping protocol and DNA samples are banked for analysis of recombination history, allele loss, and population structure. Herein we present a progress report of the Collaborative Cross breeding program at ORNL and a description of the kinds of investigations that this resource will support.

  12. Prenatal genetic counseling in cross-cultural medicine

    PubMed Central

    Bhogal, Ashvinder K.; Brunger, Fern

    2010-01-01

    Abstract OBJECTIVE To help family physicians practise effective genetic counseling and offer practical strategies for cross-cultural communication in the context of prenatal genetic counseling. SOURCES OF INFORMATION PubMed and the Cochrane Database of Systematic Reviews were searched. Most evidence was level II and some was level III. MAIN MESSAGE The values and beliefs of practitioners, no less than those of patients, are shaped by culture. In promoting a patient’s best interest, the assumptions of both the patient and the provider must be held up for examination and discussed in the attempt to arrive at a consensus. Through the explicit discussion and formation of trust, the health professionals, patients, and family members who are involved can develop a shared understanding of appropriate therapeutic goals and methods. CONCLUSION Reflecting on the cultural nature of biomedicine’s ideas about risk, disability, and normality helps us to realize that there are many valid interpretations of what is in a patient’s best interest. Self-reflection helps to ensure that respectful communication with the specific family and patient is the basis for health care decisions. Overall, this helps to improve the quality of care. PMID:20944039

  13. Crossing-Over in a Hypervariable Species Preferentially Occurs in Regions of High Local Similarity

    PubMed Central

    Seplyarskiy, Vladimir B.; Logacheva, Maria D.; Penin, Aleksey A.; Baranova, Maria A.; Leushkin, Evgeny V.; Demidenko, Natalia V.; Klepikova, Anna V.; Kondrashov, Fyodor A.; Kondrashov, Alexey S.; James, Timothy Y.

    2014-01-01

    Recombination between double-stranded DNA molecules is a key genetic process which occurs in a wide variety of organisms. Usually, crossing-over (CO) occurs during meiosis between genotypes with 98.0–99.9% sequence identity, because within-population nucleotide diversity only rarely exceeds 2%. However, some species are hypervariable and it is unclear how CO can occur between genotypes with less than 90% sequence identity. Here, we study CO in Schizophyllum commune, a hypervariable cosmopolitan basidiomycete mushroom, a frequently encountered decayer of woody substrates. We crossed two haploid individuals, from the United States and from Russia, and obtained genome sequences for their 17 offspring. The average genetic distance between the parents was 14%, making it possible to study CO at very high resolution. We found reduced levels of linkage disequilibrium between loci flanking the CO sites indicating that they are mostly confined to hotspots of recombination. Furthermore, CO events preferentially occurred in regions under stronger negative selection, in particular within exons that showed reduced levels of nucleotide diversity. Apparently, in hypervariable species CO must avoid regions of higher divergence between the recombining genomes due to limitations imposed by the mismatch repair system, with regions under strong negative selection providing the opportunity for recombination. These patterns are opposite to those observed in a number of less variable species indicating that population genomics of hypervariable species may reveal novel biological phenomena. PMID:25135947

  14. Optimal design of genetic studies of gene expression with two-color microarrays in outbred crosses.

    PubMed

    Lam, Alex C; Fu, Jingyuan; Jansen, Ritsert C; Haley, Chris S; de Koning, Dirk-Jan

    2008-11-01

    Combining global gene-expression profiling and genetic analysis of natural allelic variation (genetical genomics) has great potential in dissecting the genetic pathways underlying complex phenotypes. Efficient use of microarrays is paramount in experimental design as the cost of conducting this type of study is high. For those organisms where recombinant inbred lines are available for mapping, the "distant pair design" maximizes the number of informative contrasts over all marker loci. Here, we describe an extension of this design, named the "optimal pair design," for use with F2 crosses between outbred lines. The performance of this design is investigated by simulation and compared to several other two-color microarray designs. We show that, for a given number of microarrays, the optimal pair design outperforms all other designs considered for detection of expression quantitative trait loci (eQTL) with additive effects by linkage analysis. We also discuss the suitability of this design for outbred crosses in organisms with large genomes and for detection of dominance. PMID:18791249

  15. A Cis-Acting Locus That Promotes Crossing over between X Chromosomes in Caenorhabditis Elegans

    PubMed Central

    Villeneuve, A. M.

    1994-01-01

    This study reports the characterization of a cis-acting locus on the Caenorhabditis elegans X chromosome that is crucial for promoting normal levels of crossing over specifically between the X homologs and for ensuring their proper disjunction at meiosis I. The function of this locus is disrupted by the mutation me8, which maps to the extreme left end of the X chromosome within the region previously implicated by studies of X;A translocations and X duplications to contain a meiotic pairing site. Hermaphrodites homozygous for a deletion of the locus (Df/Df) or heterozygous for a deletion and the me8 mutation (me8/Df) exhibit extremely high levels of X chromosome nondisjunction at the reductional division; this is correlated with a sharp decrease in crossing over between the X homologs as evidenced both by reductions in genetic map distances and by the presence of achiasmate chromosomes in cytological preparations of oocyte nuclei. Duplications of the wild-type region that are unlinked to the X chromosome cannot complement the recombination and disjunction defects in trans, indicating that this region must be present in cis to the X chromosome to ensure normal levels of crossing over and proper homolog disjunction. me8 homozygotes exhibit an altered distribution of crossovers along the X chromosome that suggests a defect in processivity along the X chromosome of an event that initiates at the chromosome end. Models are discussed in which the cis-acting locus deleted by the Dfs functions as a meiotic pairing center that recruits trans-acting factors onto the chromosomes to nucleate assembly of a crossover-competent complex between the X homologs. This pairing center might function in the process of homolog recognition, or in the initiation of homologous synapsis. PMID:8005443

  16. Recent advances in modeling fission cross sections over intermediate structures

    SciTech Connect

    Bouland, Olivier; Lynn, J. Eric; Talou, Patrick

    2009-01-01

    More accurate fission cross section calculations in presence of underlying intermediate structure are strongly desired. This paper recalls the common approximations used below the fission threshold and quantifies their impact. In particular, an exact expanded R-matrix Monte Carlo calculation of the intermediate structure, deeply mixed with the fluctuations of the class-I and II decay amplitudes, is shown. This paper also insists on the microscopic structure of the level densities as a function of the nucleus deformation and show preliminary neutron induced fission cross section calculations for {sup 239}Pu and {sup 240}Pu using newly calculated combinatorial level densities. Comparisons with recent evaluated and measured fission cross sections are made.

  17. Genetic connectivity for two bear species at wildlife crossing structures in Banff National Park

    PubMed Central

    Sawaya, Michael A.; Kalinowski, Steven T.; Clevenger, Anthony P.

    2014-01-01

    Roads can fragment and isolate wildlife populations, which will eventually decrease genetic diversity within populations. Wildlife crossing structures may counteract these impacts, but most crossings are relatively new, and there is little evidence that they facilitate gene flow. We conducted a three-year research project in Banff National Park, Alberta, to evaluate the effectiveness of wildlife crossings to provide genetic connectivity. Our main objective was to determine how the Trans-Canada Highway and crossing structures along it affect gene flow in grizzly (Ursus arctos) and black bears (Ursus americanus). We compared genetic data generated from wildlife crossings with data collected from greater bear populations. We detected a genetic discontinuity at the highway in grizzly bears but not in black bears. We assigned grizzly bears that used crossings to populations north and south of the highway, providing evidence of bidirectional gene flow and genetic admixture. Parentage tests showed that 47% of black bears and 27% of grizzly bears that used crossings successfully bred, including multiple males and females of both species. Differentiating between dispersal and gene flow is difficult, but we documented gene flow by showing migration, reproduction and genetic admixture. We conclude that wildlife crossings allow sufficient gene flow to prevent genetic isolation. PMID:24552834

  18. Genetic connectivity for two bear species at wildlife crossing structures in Banff National Park.

    PubMed

    Sawaya, Michael A; Kalinowski, Steven T; Clevenger, Anthony P

    2014-04-01

    Roads can fragment and isolate wildlife populations, which will eventually decrease genetic diversity within populations. Wildlife crossing structures may counteract these impacts, but most crossings are relatively new, and there is little evidence that they facilitate gene flow. We conducted a three-year research project in Banff National Park, Alberta, to evaluate the effectiveness of wildlife crossings to provide genetic connectivity. Our main objective was to determine how the Trans-Canada Highway and crossing structures along it affect gene flow in grizzly (Ursus arctos) and black bears (Ursus americanus). We compared genetic data generated from wildlife crossings with data collected from greater bear populations. We detected a genetic discontinuity at the highway in grizzly bears but not in black bears. We assigned grizzly bears that used crossings to populations north and south of the highway, providing evidence of bidirectional gene flow and genetic admixture. Parentage tests showed that 47% of black bears and 27% of grizzly bears that used crossings successfully bred, including multiple males and females of both species. Differentiating between dispersal and gene flow is difficult, but we documented gene flow by showing migration, reproduction and genetic admixture. We conclude that wildlife crossings allow sufficient gene flow to prevent genetic isolation. PMID:24552834

  19. "Over the River": Border Childhoods and Border Crossings at Niagara

    ERIC Educational Resources Information Center

    Helleiner, Jane

    2007-01-01

    Drawing on interviews with Canadian borderlanders, this article examines childhood experiences with the Canada--US border in the mid-1980s to early 1990s. The retrospective accounts of childhood border experiences demonstrate how childhood was produced and experienced in border crossings and how the production of childhood intersected with a…

  20. Publication Trends Over 55 Years of Behavioral Genetic Research.

    PubMed

    Ayorech, Ziada; Selzam, Saskia; Smith-Woolley, Emily; Knopik, Valerie S; Neiderhiser, Jenae M; DeFries, John C; Plomin, Robert

    2016-09-01

    We document the growth in published papers on behavioral genetics for 5-year intervals from 1960 through 2014. We used 1861 papers published in Behavior Genetics to train our search strategy which, when applied to Ovid PsychINFO, selected more than 45,000 publications. Five trends stand out: (1) the number of behavioral genetic publications has grown enormously; nearly 20,000 papers were published in 2010-2014. (2) The number of human quantitative genetic (QG) publications (e.g., twin and adoption studies) has steadily increased with more than 3000 papers published in 2010-2014. (3) The number of human molecular genetic (MG) publications increased substantially from about 2000 in 2000-2004 to 5000 in 2005-2009 to 9000 in 2010-2014. (4) Nonhuman publications yielded similar trends. (5) Although there has been exponential growth in MG publications, both human and nonhuman QG publications continue to grow. A searchable resource of this corpus of behavioral genetic papers is freely available online at http://www.teds.ac.uk/public_datasets.html and will be updated annually. PMID:26992731

  1. Nineteenth century French rose (Rosa sp.) germplasm shows a shift over time from a European to an Asian genetic background

    PubMed Central

    Liorzou, Mathilde; Pernet, Alix; Li, Shubin; Chastellier, Annie; Thouroude, Tatiana; Michel, Gilles; Malécot, Valéry; Gaillard, Sylvain; Briée, Céline; Foucher, Fabrice; Oghina-Pavie, Cristiana; Clotault, Jérémy; Grapin, Agnès

    2016-01-01

    Hybridization with introduced genetic resources is commonly practiced in ornamental plant breeding to introgress desired traits. The 19th century was a golden age for rose breeding in France. The objective here was to study the evolution of rose genetic diversity over this period, which included the introduction of Asian genotypes into Europe. A large sample of 1228 garden roses encompassing the conserved diversity cultivated during the 18th and 19th centuries was genotyped with 32 microsatellite primer pairs. Its genetic diversity and structure were clarified. Wide diversity structured in 16 genetic groups was observed. Genetic differentiation was detected between ancient European and Asian accessions, and a temporal shift from a European to an Asian genetic background was observed in cultivated European hybrids during the 19th century. Frequent crosses with Asian roses throughout the 19th century and/or selection for Asiatic traits may have induced this shift. In addition, the consistency of the results with respect to a horticultural classification is discussed. Some horticultural groups, defined according to phenotype and/or knowledge of their pedigree, seem to be genetically more consistent than others, highlighting the difficulty of classifying cultivated plants. Therefore, the horticultural classification is probably more appropriate for commercial purposes rather than genetic relatedness, especially to define preservation and breeding strategies. PMID:27406785

  2. Relationships between Parenting and Adolescent Adjustment Over Time: Genetic and Environmental Contributions.

    ERIC Educational Resources Information Center

    Neiderhiser, Jenae M.; Reiss, David; Plomin, Robert; Hetherington, E. Mavis

    1999-01-01

    Examined the genetic and environmental contributions to the predictive association between parenting and adolescent adjustment in identical and fraternal twins, and full, half, and genetically unrelated siblings in nondivorced and stepfamilies. Found that cross-lagged associations between parental conflict-negativity and adolescent antisocial…

  3. Designing a Unique Single Point Cross Over Method

    NASA Technical Reports Server (NTRS)

    Wilson, Richard Phillip

    2002-01-01

    The idea behind genetic algorithms is to extract optimization strategies nature uses successfully - known as Darwinian Evolution - and transform them for application in mathematical optimization theory to find the global optimum in a defined phase space. One could imagine a population of individual 'explorers' sent into the optimization phase-space. Each explorer is defined by its genes, what means, its position inside the phase-space is coded in his genes. Every explorer has the duty to find a value of the quality of his position in the phase space. (Consider the phase-space being a number of variables in some technological process, the value of quality of any position in the phase space - in other words: any set of the variables - can be expressed by the yield of the desired chemical product.) Then the struggle of 'life' begins. The three fundamental principles are selection, mating/crossover, and mutation. Only explorers (= genes) sitting on the best places will reproduce and create a new population. This is performed in the second step (mating/crossover). The 'hope' behind this part of the algorithm is, that 'good' sections of two parents will be recombined to yet better fitting children. In fact, many of the created children will not be successful (as in biological evolution), but a few children will indeed fulfill this hope. These good sections are named in some publications as building blocks. Now there appears a problem. Repeating these steps, no new area would be explored. The two former steps would only exploit the already known regions in the phase space, which could lead to premature convergence of the algorithm with the consequence of missing the global optimum by exploiting some local optimum. The third step, mutation, ensures the necessary accidental effects. One can imagine the new population being mixed up a little bit to bring some new information into this set of genes. Whereas in biology a gene is described as a macro-molecule with four

  4. Comparative genetic analysis of lint yield and fiber quality among single, three-way, and double crosses in upland cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Decisions on the appropriate crossing systems to employ for genetic improvement of quantitative traits are critical in cotton breeding. Determination of genetic variance for lint yield and fiber quality in three different crossing schemes, i.e., single cross (SC), three-way cross (TWC), and double ...

  5. A Genetically Informed Cross-Lagged Analysis of Autistic-Like Traits and Affective Problems in Early Childhood.

    PubMed

    Micalizzi, Lauren; Ronald, Angelica; Saudino, Kimberly J

    2016-07-01

    A genetically informed cross-lagged model was applied to twin data to explore etiological links between autistic-like traits and affective problems in early childhood. The sample comprised 310 same-sex twin pairs (143 monozygotic and 167 dizygotic; 53 % male). Autistic-like traits and affective problems were assessed at ages 2 and 3 using parent ratings. Both constructs were related within and across age (r = 0.30-0.53) and showed moderate stability (r = 0.45-0.54). Autistic-like traits and affective problems showed genetic and environmental influences at both ages. Whereas at age 2, the covariance between autistic-like traits and affective problems was entirely due to environmental influences (shared and nonshared), at age 3, genetic factors also contributed to the covariance between constructs. The stability paths, but not the cross-lagged paths, were significant, indicating that there is stability in both autistic-like traits and affective problems but they do not mutually influence each other across age. Stability effects were due to genetic, shared, and nonshared environmental influences. Substantial novel genetic and nonshared environmental influences emerge at age 3 and suggest change in the etiology of these constructs over time. During early childhood, autistic-like traits tend to occur alongside affective problems and partly overlapping genetic and environmental influences explain this association. PMID:26456961

  6. Complex genetic diseases: controversy over the Croesus code.

    PubMed

    Wright, A F; Hastie, N D

    2001-01-01

    The polarization of views on how best to exploit new information from the Human Genome Project for medicine reflects our ignorance of the genetic architecture underlying common diseases: are susceptibility alleles common or rare, neutral or deleterious, few or many? Single-nucleotide polymorphism (SNP) technology is almost in place to dissect such diseases and to create a personalized medicine, but success is critically dependent on the biology and "Nature to be commanded must be obeyed" (Francis Bacon, 1620, Novum Organum). PMID:11532206

  7. Controversy over genetically modified organisms: the governing laws and regulations.

    PubMed

    Keatley, K L

    2000-01-01

    Genetically Modified Organisms (GMOs) are increasingly becoming a topic of controversy in the U.S. and abroad. The public is questioning their safety and wanting the products labeled as genetically modified. There are other concerns from some of the scientific world and some government officials and organizations such as the Food & Agricultural Organization (FAO) that question whether adequate research has been done to qualify GMOs as safe for long-term use. Of particular concern are the allergenic properties, a GMO may impart, possible transfer effects of antibiotic resistance (given that antibiotic resistant marker genes are used for many GMOs), the expression of previously unexpressed traits, and the drift of pollen from genetically modified crops. It has also been noted that the laws and regulations governing the biotechnology world are outdated, are not comprehensive, and span too many agencies. The primary agencies currently regulating biotechnology are the U.S. Department of Agriculture (USDA), the Food and Drug Administration (FDA), and the Environmental Protection Agency (EPA). PMID:11710306

  8. Predicting Phenotypes from Genetic Crosses: A Mathematical Concept to Help Struggling Biology Students

    ERIC Educational Resources Information Center

    Baurhoo, Neerusha; Darwish, Shireef

    2012-01-01

    Predicting phenotypic outcomes from genetic crosses is often very difficult for biology students, especially those with learning disabilities. With our mathematical concept, struggling students in inclusive biology classrooms are now better equipped to solve genetic problems and predict phenotypes, because of improved understanding of dominance…

  9. Quantitative genetically nonequivalent reciprocal crosses in cultivated plants.

    PubMed

    Aksel, R

    Quantitative expressions of character difference between reciprocal crosses have been studied by different researchers in a number of plant species, such as Epilobium, Zea mays, Oryza sativa, Hordeum sativum, Triticum aestivum, Trifolium hybridum, Linum usitatissimum, Nicotiana rustica, and others. In all cases it was found that the nonequivalence of reciprocal crosses manifested itself beginning with the F1 generation, with the exception of some flax crosses in which reciprocals differed beginning with the F2 generation. The nonequivalence of reciprocal crosses usually manifested itself in the inequality of their F1 and/or F2 or backcross means; however, there were instances in which their means were the same but the variances were different. Both matroclinous and patroclinous inheritances were reported in plants. Because of the casual complexity of reciprocal differences the experimental results often lack a simple explanation. PMID:1032105

  10. Study of Genetic Diversity among Simmental Cross Cattle in West Sumatra Based on Microsatellite Markers.

    PubMed

    Agung, Paskah Partogi; Saputra, Ferdy; Septian, Wike Andre; Lusiana; Zein, Moch Syamsul Arifin; Sulandari, Sri; Anwar, Saiful; Wulandari, Ari Sulistyo; Said, Syahruddin; Tappa, Baharuddin

    2016-02-01

    A study was conducted to assess the genetic diversity among Simmental Cross cattle in West Sumatra using microsatellite DNA markers. A total of 176 individual cattle blood samples was used for obtaining DNA samples. Twelve primers of microsatellite loci as recommended by FAO were used to identify the genetic diversity of the Simmental Cross cattle population. Multiplex DNA fragment analysis method was used for allele identification. All the microsatellite loci in this study were highly polymorphic and all of the identified alleles were able to classify the cattle population into several groups based on their genetic distance. The heterozygosity values of microsatellite loci in this study ranged from 0.556 to 0.782. The polymorphism information content (PIC) value of the 12 observed loci is high (PIC>0.5). The highest PIC value in the Simmental cattle population was 0.893 (locus TGLA53), while the lowest value was 0.529 (locus BM1818). Based on the genetic distance value, the subpopulation of the Simmental Cross-Agam and the Simmental Cross-Limapuluh Kota was exceptionally close to the Simmental Purebred thus indicating that a grading-up process has taken place with the Simmental Purebred. In view of the advantages possessed by the Simmental Cross cattle and the evaluation of the genetic diversity results, a number of subpopulations in this study can be considered as the initial (base) population for the Simmental Cross cattle breeding programs in West Sumatra, Indonesia. PMID:26732442

  11. Study of Genetic Diversity among Simmental Cross Cattle in West Sumatra Based on Microsatellite Markers

    PubMed Central

    Agung, Paskah Partogi; Saputra, Ferdy; Septian, Wike Andre; Lusiana; Zein, Moch. Syamsul Arifin; Sulandari, Sri; Anwar, Saiful; Wulandari, Ari Sulistyo; Said, Syahruddin; Tappa, Baharuddin

    2016-01-01

    A study was conducted to assess the genetic diversity among Simmental Cross cattle in West Sumatra using microsatellite DNA markers. A total of 176 individual cattle blood samples was used for obtaining DNA samples. Twelve primers of microsatellite loci as recommended by FAO were used to identify the genetic diversity of the Simmental Cross cattle population. Multiplex DNA fragment analysis method was used for allele identification. All the microsatellite loci in this study were highly polymorphic and all of the identified alleles were able to classify the cattle population into several groups based on their genetic distance. The heterozygosity values of microsatellite loci in this study ranged from 0.556 to 0.782. The polymorphism information content (PIC) value of the 12 observed loci is high (PIC>0.5). The highest PIC value in the Simmental cattle population was 0.893 (locus TGLA53), while the lowest value was 0.529 (locus BM1818). Based on the genetic distance value, the subpopulation of the Simmental Cross-Agam and the Simmental Cross-Limapuluh Kota was exceptionally close to the Simmental Purebred thus indicating that a grading-up process has taken place with the Simmental Purebred. In view of the advantages possessed by the Simmental Cross cattle and the evaluation of the genetic diversity results, a number of subpopulations in this study can be considered as the initial (base) population for the Simmental Cross cattle breeding programs in West Sumatra, Indonesia. PMID:26732442

  12. Formation of interference-sensitive meiotic cross-overs requires sufficient DNA leading-strand elongation

    PubMed Central

    Huang, Jiyue; Cheng, Zhihao; Wang, Cong; Hong, Yue; Su, Hang; Wang, Jun; Copenhaver, Gregory P.; Ma, Hong; Wang, Yingxiang

    2015-01-01

    Meiosis halves diploid genomes to haploid and is essential for sexual reproduction in eukaryotes. Meiotic recombination ensures physical association of homologs and their subsequent accurate segregation and results in the redistribution of genetic variations among progeny. Most organisms have two classes of cross-overs (COs): interference-sensitive (type I) and -insensitive (type II) COs. DNA synthesis is essential for meiotic recombination, but whether DNA synthesis has a role in differentiating meiotic CO pathways is unknown. Here, we show that Arabidopsis POL2A, the homolog of the yeast DNA polymerase-ε (a leading-strand DNA polymerase), is required for plant fertility and meiosis. Mutations in POL2A cause reduced fertility and meiotic defects, including abnormal chromosome association, improper chromosome segregation, and fragmentation. Observation of prophase I cell distribution suggests that pol2a mutants likely delay progression of meiotic recombination. In addition, the residual COs in pol2a have reduced CO interference, and the double mutant of pol2a with mus81, which affects type II COs, displayed more severe defects than either single mutant, indicating that POL2A functions in the type I pathway. We hypothesize that sufficient leading-strand DNA elongation promotes formation of some type I COs. Given that meiotic recombination and DNA synthesis are conserved in divergent eukaryotes, this study and our previous study suggest a novel role for DNA synthesis in the differentiation of meiotic recombination pathways. PMID:26392549

  13. Optimal vaccination schedule search using genetic algorithm over MPI technology

    PubMed Central

    2012-01-01

    Background Immunological strategies that achieve the prevention of tumor growth are based on the presumption that the immune system, if triggered before tumor onset, could be able to defend from specific cancers. In supporting this assertion, in the last decade active immunization approaches prevented some virus-related cancers in humans. An immunopreventive cell vaccine for the non-virus-related human breast cancer has been recently developed. This vaccine, called Triplex, targets the HER-2-neu oncogene in HER-2/neu transgenic mice and has shown to almost completely prevent HER-2/neu-driven mammary carcinogenesis when administered with an intensive and life-long schedule. Methods To better understand the preventive efficacy of the Triplex vaccine in reduced schedules we employed a computational approach. The computer model developed allowed us to test in silico specific vaccination schedules in the quest for optimality. Specifically here we present a parallel genetic algorithm able to suggest optimal vaccination schedule. Results & Conclusions The enormous complexity of combinatorial space to be explored makes this approach the only possible one. The suggested schedule was then tested in vivo, giving good results. Finally, biologically relevant outcomes of optimization are presented. PMID:23148787

  14. Handling Arabidopsis plants: growth, preservation of seeds, transformation, and genetic crosses.

    PubMed

    Rivero, Luz; Scholl, Randy; Holomuzki, Nicholas; Crist, Deborah; Grotewold, Erich; Brkljacic, Jelena

    2014-01-01

    Growing healthy plants is essential for the advancement of Arabidopsis thaliana (Arabidopsis) research. Over the last 20 years, the Arabidopsis Biological Resource Center (ABRC) has collected and developed a series of best-practice protocols, some of which are presented in this chapter. Arabidopsis can be grown in a variety of locations, growth media, and environmental conditions. Most laboratory accessions and their mutant or transgenic derivatives flower after 4-5 weeks and set seeds after 7-8 weeks, under standard growth conditions (soil, long day, 23 ºC). Some mutant genotypes, natural accessions, and Arabidopsis relatives require strict control of growth conditions best provided by growth rooms, chambers, or incubators. Other lines can be grown in less-controlled greenhouse settings. Although the majority of lines can be grown in soil, certain experimental purposes require utilization of sterile solid or liquid growth media. These include the selection of primary transformants, identification of homozygous lethal individuals in a segregating population, or bulking of a large amount of plant material. The importance of controlling, observing, and recording growth conditions is emphasized and appropriate equipment required to perform monitoring of these conditions is listed. Proper conditions for seed harvesting and preservation, as well as seed quality control, are also described. Plant transformation and genetic crosses, two of the methods that revolutionized Arabidopsis genetics, are introduced as well. PMID:24057358

  15. Molecular genetic perspectives on cross-talk and specificity in abiotic stress signalling in plants.

    PubMed

    Chinnusamy, Viswanathan; Schumaker, Karen; Zhu, Jian-Kang

    2004-01-01

    The perception of abiotic stresses and signal transduction to switch on adaptive responses are critical steps in determining the survival and reproduction of plants exposed to adverse environments. Plants have stress-specific adaptive responses as well as responses which protect the plants from more than one environmental stress. There are multiple stress perception and signalling pathways, some of which are specific, but others may cross-talk at various steps. Recently, progress has been made in identifying components of signalling pathways involved in salt, drought and cold stresses. Genetic analysis has defined the Salt-Overly-Sensitive (SOS) pathway, in which a salt stress-induced calcium signal is probably sensed by the calcium-binding protein SOS3 which then activates the protein kinase SOS2. The SOS3-SOS2 kinase complex regulates the expression and activity of ion transporters such as SOS1 to re-establish cellular ionic homeostasis under salinity. The ICE1 (Inducer of CBF Expression 1)-CBF (C-Repeat Binding Protein) pathway is critical for the regulation of the cold-responsive transcriptome and acquired freezing tolerance, although at present the signalling events that activate the ICE1 transcription factor during cold stress are not known. Both ABA-dependent and -independent signalling pathways appear to be involved in osmotic stress tolerance. Components of mitogen-activated protein kinase (MAPK) cascades may act as converging points of multiple abiotic as well as biotic stress signalling pathways. Forward and reverse genetic analysis in combination with expression profiling will continue to uncover many signalling components, and biochemical characterization of the signalling complexes will be required to determine specificity and cross-talk in abiotic stress signalling pathways. PMID:14673035

  16. Genetic evaluation of Ethiopian Boran cattle and their crosses with Holstein Friesian for growth performance in central Ethiopia.

    PubMed

    Haile, A; Joshi, B K; Ayalew, W; Tegegne, A; Singh, A

    2011-04-01

    Breed additive and non-additive effects, and heritabilities of birth weight (BWT), weaning weight (WWT), 6 months weight (SMWT), yearling weight (YWT), eighteen months weight (EWT), 2 years weight (TWT) and average daily weight gain from birth to 6 months (ADG1) and from 6 months to 2 years (ADG2) were estimated in Ethiopian Boran (B) cattle and their crosses with Holstein Friesian (F) in central Ethiopia. The data analysed were spread over 15 years. Ethiopian Boran were consistently lighter (p < 0.01) than the B-F crosses at all ages. Ethiopian Boran also gained lower weight than all the crosses. At birth, 50% F crosses were significantly (p < 0.01) lighter than all the other crosses. However, the differences in SMWT, YWT, EWT, TWT, ADG1 and ADG2 were all non-significant among the crosses. The individual additive breed differences between B and F breeds were positive and significant (p < 0.01) for all traits. The individual heterosis effects were significant (p < 0.05) for all traits except WWT for which the effect was non-significant. The maternal heterosis effects were significant (p < 0.01) for BWT (2.5 kg) and WWT (-3.0 kg). The heritability estimates for all traits in B and crosses were generally moderate to high indicating that there is scope for genetic improvement through selection. Selection within B and crossbreeding should be the strategy to enhance the growth performance under such production systems. PMID:21385228

  17. Calculation of linearized supersonic flow over slender cones of arbitrary cross section

    NASA Technical Reports Server (NTRS)

    Mascitti, V. R.

    1972-01-01

    Supersonic linearized conical-flow theory is used to determine the flow over slender pointed cones having horizontal and vertical planes of symmetry. The geometry of the cone cross sections and surface velocities are expanded in Fourier series. The symmetry condition permits the uncoupling of lifting and nonlifting solutions. The present method reduces to Ward's theory for flow over a cone of elliptic cross section. Results are also presented for other shapes. Results by this method diverge for cross-sectional shapes where the maximum thickness is large compared with the minimum thickness. However, even for these slender-body shapes, lower order solutions are good approximations to the complete solution.

  18. Inherited differences in crossing over and gene conversion frequencies between wild strains of Sordaria fimicola from "Evolution Canyon".

    PubMed Central

    Saleem, M; Lamb, B C; Nevo, E

    2001-01-01

    Recombination generates new combinations of existing genetic variation and therefore may be important in adaptation and evolution. We investigated whether there was natural genetic variation for recombination frequencies and whether any such variation was environment related and possibly adaptive. Crossing over and gene conversion frequencies often differed significantly in a consistent direction between wild strains of the fungus Sordaria fimicola isolated from a harsher or a milder microscale environment in "Evolution Canyon," Israel. First- and second-generation descendants from selfing the original strains from the harsher, more variable, south-facing slope had higher frequencies of crossing over in locus-centromere intervals and of gene conversion than those from the lusher north-facing slopes. There were some significant differences between strains within slopes, but these were less marked than between slopes. Such inherited variation could provide a basis for natural selection for optimum recombination frequencies in each environment. There were no significant differences in meiotic hybrid DNA correction frequencies between strains from the different slopes. The conversion analysis was made using only conversions to wild type, because estimations of conversion to mutant were affected by a high frequency of spontaneous mutation. There was no polarized segregation of chromosomes at meiosis I or of chromatids at meiosis II. PMID:11779798

  19. CRISPR-directed mitotic recombination enables genetic mapping without crosses.

    PubMed

    Sadhu, Meru J; Bloom, Joshua S; Day, Laura; Kruglyak, Leonid

    2016-05-27

    Linkage and association studies have mapped thousands of genomic regions that contribute to phenotypic variation, but narrowing these regions to the underlying causal genes and variants has proven much more challenging. Resolution of genetic mapping is limited by the recombination rate. We developed a method that uses CRISPR (clustered, regularly interspaced, short palindromic repeats) to build mapping panels with targeted recombination events. We tested the method by generating a panel with recombination events spaced along a yeast chromosome arm, mapping trait variation, and then targeting a high density of recombination events to the region of interest. Using this approach, we fine-mapped manganese sensitivity to a single polymorphism in the transporter Pmr1. Targeting recombination events to regions of interest allows us to rapidly and systematically identify causal variants underlying trait differences. PMID:27230379

  20. Diverse genetic architectures lead to the same cryptic phenotype in a yeast cross

    PubMed Central

    Taylor, Matthew B.; Phan, Joann; Lee, Jonathan T.; McCadden, Madelyn; Ehrenreich, Ian M.

    2016-01-01

    Cryptic genetic variants that do not typically influence traits can interact epistatically with each other and mutations to cause unexpected phenotypes. To improve understanding of the genetic architectures and molecular mechanisms that underlie these interactions, we comprehensively dissected the genetic bases of 17 independent instances of the same cryptic colony phenotype in a yeast cross. In eight cases, the phenotype resulted from a genetic interaction between a de novo mutation and one or more cryptic variants. The number and identities of detected cryptic variants depended on the mutated gene. In the nine remaining cases, the phenotype arose without a de novo mutation due to two different classes of higher-order genetic interactions that only involve cryptic variants. Our results may be relevant to other species and disease, as most of the mutations and cryptic variants identified in our study reside in components of a partially conserved and oncogenic signalling pathway. PMID:27248513

  1. Crossing-over in rearranging chromosomes of Drosophila: The role of delayed pairing

    SciTech Connect

    Chadov, B.F.; Chadova, E.V.; Khotskina, E.A.

    1995-11-01

    A Df(2R)MS2-10 deletion of pericentromeric heterochromatin and an Is(Y;2L)419 insertion of Y material in the region 34A, as well as nondisjunction of chromosomes 2 in 2/F(2L); F(2R) females did not directly prevent chromosome arms in chromosome 2 of Drosophila from pairing. However, these events resulted in (1) two- to four-fold decrease in the rate of crossing-over in chromosome 2; (2) a decreased proportion of exchange tetrads two to three times greater for multiple-exchange tetrads than for single-exchange ones; and (3) a decreased rate of crossing-over throughout the entire chromosome arm enhanced in a proximal direction. An In(1)dl-49+B{sup M1}inversion in the X chromosome cancelled the suppression of crossing-over. Crossing-over increased due to an increasing proportion of single-exchange tretrads. The changes in crossing-over found cannot be explained by asynapsis in the chromosomes with rearrangements. According to the authors, these changes are probably accounted for by a delayed pairing of these chromosomes. The delayed pairing of individual chromosome regions or the whole chromosome is considered the most common type of pairing disturbance. It effects on meiosis are discussed. 39 refs., 6 figs., 1 tab.

  2. A Cross-Sectional Study of Ageing and Cardiovascular Function over the Baboon Lifespan

    PubMed Central

    Yeung, Kristen R.; Pears, Suzanne; Heffernan, Scott J.; Makris, Angela; Hennessy, Annemarie; Lind, Joanne M.

    2016-01-01

    Background Ageing is associated with changes at the molecular and cellular level that can alter cardiovascular function and ultimately lead to disease. The baboon is an ideal model for studying ageing due to the similarities in genetic, anatomical, physiological and biochemical characteristics with humans. The aim of this cross-sectional study was to investigate the changes in cardiovascular profile of baboons over the course of their lifespan. Methods Data were collected from 109 healthy baboons (Papio hamadryas) at the Australian National Baboon Colony. A linear regression model, adjusting for sex, was used to analyse the association between age and markers of ageing with P < 0.01 considered significant. Results Male (n = 49, 1.5–28.5 years) and female (n = 60, 1.8–24.6 years) baboons were included in the study. Age was significantly correlated with systolic (R2 = 0.23, P < 0.001) and diastolic blood pressure (R2 = 0.44, P < 0.001), with blood pressure increasing with age. Age was also highly correlated with core augmentation index (R2 = 0.17, P < 0.001) and core pulse pressure (R2 = 0.30, P < 0.001). Creatinine and urea were significantly higher in older animals compared to young animals (P < 0.001 for both). Older animals (>12 years) had significantly shorter telomeres when compared to younger (<3 years) baboons (P = 0.001). Conclusion This study is the first to demonstrate that cardiovascular function alters with age in the baboon. This research identifies similarities within cardiovascular parameters between humans and baboon even though the length of life differs between the two species. PMID:27427971

  3. High genetic differentiation and cross-shelf patterns of genetic diversity among Great Barrier Reef populations of Symbiodinium

    NASA Astrophysics Data System (ADS)

    Howells, E. J.; van Oppen, M. J. H.; Willis, B. L.

    2009-03-01

    The resilience of Symbiodinium harboured by corals is dependent on the genetic diversity and extent of connectivity among reef populations. This study presents genetic analyses of Great Barrier Reef (GBR) populations of clade C Symbiodinium hosted by the alcyonacean coral, Sinularia flexibilis. Allelic variation at four newly developed microsatellite loci demonstrated that Symbiodinium populations are genetically differentiated at all spatial scales from 16 to 1,360 km (pairwise ΦST = 0.01-0.47, mean = 0.22); the only exception being two neighbouring populations in the Cairns region separated by 17 km. This indicates that gene flow is restricted for Symbiodinium C hosted by S. flexibilis on the GBR. Patterns of population structure reflect longshore circulation patterns and limited cross-shelf mixing, suggesting that passive transport by currents is the primary mechanism of dispersal in Symbiodinium types that are acquired horizontally. There was no correlation between the genetic structure of Symbiodinium populations and their host S. flexibilis, most likely because different factors affect the dispersal and recruitment of each partner in the symbiosis. The genetic diversity of these Symbiodinium reef populations is on average 1.5 times lower on inshore reefs than on offshore reefs. Lower inshore diversity may reflect the impact of recent bleaching events on Sinularia assemblages, which have been more widespread and severe on inshore reefs, but may also have been shaped by historical sea level fluctuations or recent migration patterns.

  4. Heritabilities and genetic correlations for reproductive traits in an F2 reciprocal cross chicken population.

    PubMed

    Savegnago, R P; Buzanskas, M E; Nunes, B N; Ramos, S B; Ledur, M C; Nones, K; Munari, D P

    2011-01-01

    Studies estimating genetic parameters for reproductive traits in chickens can be useful for understanding and improvement of their genetic architecture. A total of 1276 observations of fertility (FERT), hatchability of fertile eggs (HFE) and hatchability of total eggs (HTE) were used to estimate the genetic and phenotypic parameters of 467 females from an F2 population generated by reciprocal crossing between a broiler line and a layer line, which were developed through a poultry genetics breeding program, maintained by Embrapa Swine and Poultry, Concordia, Santa Catarina, Brazil. Estimates of heritability and genetic and phenotypic correlations were obtained using restricted maximum likelihood calculations under the two-trait animal model, including the fixed effect of group (hatching of birds from the same genetic group) and the random additive genetic and residual effects. The mean percentages for FERT, HFE and HTE were 87.91 ± 19.77, 80.07 ± 26.81 and 70.67 ± 28.55%, respectively. The highest heritability estimate (h(2)) was 0.28 ± 0.04 for HTE. Genetic correlations for FERT with HFE (0.43 ± 0.17), HFE with HTE (0.98 ± 0.02) and FERT with HTE (0.69 ± 0.10) were positive and significant. Individuals with high breeding value for HTE would have high breeding values for HFE and FERT because of the high genetic association between them. These results suggest that HTE should be included as a selection criterion in genetic breeding programs to improve the reproductive performance of chickens, because HTE had the highest heritability estimate and high genetic correlation with FERT and HFE, and it is the easiest to measure. PMID:21751160

  5. Design of MEMS based `cross over junction' for T-type switch

    NASA Astrophysics Data System (ADS)

    Maninder, K.; Bansal, Deepak; Rangra, K. J.

    2016-04-01

    This paper presents a novel design approach of T-type RF MEMS switch cross over junction, implemented using symmetric toggle switch (STS) as a basic building block. T-type switches are key elements for designing redundancy switch matrices. Proposed design is a dual type switch, i.e. under operation same bridge is used as an ohmic series switch as well as a capacitive shunt switch. This reconfigurable switch constitutes the cross over junction part for the T-type switch. Simulated results show an insertion loss of < 0.2 dB upto 10 Ghz and isolation is better than -20 dB over a band of 5 Ghz through capacitive path and is better than -80 dB up-to 10 Ghz through ohmic contact path. STS as a building block is used for designing cross over junction and is a technologically mature device. The designed actuation voltage of this cross over switch is 4.75 Volts and simulated resonant frequency is 3.253 KHz.

  6. Rotationally elastic total cross sections for NH3 on electron impact over a wide energy range

    NASA Astrophysics Data System (ADS)

    Vinodkumar, Minaxi; Limbachiya, Chetan; Antony, Bobby

    2011-10-01

    Electron molecule collisions are important over incident energy from very low (0.01 eV) to intermediate and high energies (10 keV). We present rotationally elastic total cross sections for electron scattering for NH3 from 0.01 eV to 2 keV using two different theoretical formalisms. We use Quantemol-N formalism for calculating total cross sections up to threshold of the target and the Spherical Optical Complex Potential (SCOP) method for calculating total cross sections beyond threshold up to 2 keV. Electron molecule collisions are important over incident energy from very low (0.01 eV) to intermediate and high energies (10 keV). We present rotationally elastic total cross sections for electron scattering for NH3 from 0.01 eV to 2 keV using two different theoretical formalisms. We use Quantemol-N formalism for calculating total cross sections up to threshold of the target and the Spherical Optical Complex Potential (SCOP) method for calculating total cross sections beyond threshold up to 2 keV. MVK and BA thank DST, CGL thanks UGC new Delhi.

  7. The genetical basis of hybrid vigour in a highly heterotic cross of Nicotiana tabacum.

    PubMed

    Pooni, H S; Virk, P S; Coombs, D T; Chowdhury, M K

    1994-12-01

    The genetical control of F1 heterosis, observed in a cross of desirable Nicotiana tabacum varieties, was investigated by analysing the data of the basic generations, triple test cross-families and random samples of doubled haploids (DH) and single-seed descent (SSD) lines. Analyses of the first-degree statistics revealed a complex control underlying the genetic variation, including the presence of epistasis, linkage, maternal effects and their interactions, in addition to the additive and dominance effects of the genes segregating in the cross. These analyses identified gene dispersion, directional dominance, and duplicate epistasis, as the main causes of heterosis. The triple test-cross analysis also confirmed the presence of non-allelic interactions and indicated that the dominance ratio, although inflated by epistasis, is consistently partial for all the traits. The extent of transgression in the recombinant inbred lines finally established unequivocally that, as in numerous other crosses, gene dispersion and unidirectional, but partial, dominance are the true causes of heterosis in this cross too. PMID:24178120

  8. Genetic analysis of albuminuria in collaborative cross and multiple mouse intercross populations.

    PubMed

    Thaisz, Jill; Tsaih, Shirng-Wern; Feng, Minjie; Philip, Vivek M; Zhang, Yunyu; Yanas, Liane; Sheehan, Susan; Xu, Lingfei; Miller, Darla R; Paigen, Beverly; Chesler, Elissa J; Churchill, Gary A; Dipetrillo, Keith

    2012-10-01

    Albuminuria is an important marker of nephropathy that increases the risk of progressive renal and chronic cardiovascular diseases. The genetic basis of kidney disease is well-established in humans and rodent models, but the causal genes remain to be identified. We applied several genetic strategies to map and refine genetic loci affecting albuminuria in mice and translated the findings to human kidney disease. First, we measured albuminuria in mice from 33 inbred strains, used the data for haplotype association mapping (HAM), and detected 10 genomic regions associated with albuminuria. Second, we performed eight F(2) intercrosses between genetically diverse strains to identify six loci underlying albuminuria, each of which was concordant to kidney disease loci in humans. Third, we used the Oak Ridge National Laboratory incipient Collaborative Cross subpopulation to detect an additional novel quantitative trait loci (QTL) underlying albuminuria. We also performed a ninth intercross, between genetically similar strains, that substantially narrowed an albuminuria QTL on Chromosome 17 to a region containing four known genes. Finally, we measured renal gene expression in inbred mice to detect pathways highly correlated with albuminuria. Expression analysis also identified Glcci1, a gene known to affect podocyte structure and function in zebrafish, as a strong candidate gene for the albuminuria QTL on Chromosome 6. Overall, these findings greatly enhance our understanding of the genetic basis of albuminuria in mice and may guide future studies into the genetic basis of kidney disease in humans. PMID:22859403

  9. 43 CFR 4300.80 - How can I get a permit to cross reindeer over public lands?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false How can I get a permit to cross reindeer... ADMINISTRATION; ALASKA; REINDEER; GENERAL Reindeer Crossing Permits § 4300.80 How can I get a permit to cross reindeer over public lands? (a) BLM may issue a crossing permit free of charge when you file an...

  10. 43 CFR 4300.80 - How can I get a permit to cross reindeer over public lands?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false How can I get a permit to cross reindeer... ADMINISTRATION; ALASKA; REINDEER; GENERAL Reindeer Crossing Permits § 4300.80 How can I get a permit to cross reindeer over public lands? (a) BLM may issue a crossing permit free of charge when you file an...

  11. 43 CFR 4300.80 - How can I get a permit to cross reindeer over public lands?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false How can I get a permit to cross reindeer... ADMINISTRATION; ALASKA; REINDEER; GENERAL Reindeer Crossing Permits § 4300.80 How can I get a permit to cross reindeer over public lands? (a) BLM may issue a crossing permit free of charge when you file an...

  12. 43 CFR 4300.80 - How can I get a permit to cross reindeer over public lands?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false How can I get a permit to cross reindeer... ADMINISTRATION; ALASKA; REINDEER; GENERAL Reindeer Crossing Permits § 4300.80 How can I get a permit to cross reindeer over public lands? (a) BLM may issue a crossing permit free of charge when you file an...

  13. A comparison of Anopheles gambiae and Plasmodium falciparum genetic structure over space and time.

    PubMed

    Prugnolle, Franck; Durand, Patrick; Jacob, Koella; Razakandrainibe, Fabien; Arnathau, Céline; Villarreal, Diana; Rousset, François; de Meeûs, Thierry; Renaud, François

    2008-03-01

    Population genetic structure and subdivision are key factors affecting the evolution of organisms. In this study, we analysed and compared the population genetic structure of the malaria parasite Plasmodium falciparum and its mosquito vector Anopheles gambiae over space and time in the Nianza Province, near Victoria Lake in Kenya. The parasites were collected from mosquitoes caught in six villages separated by up to 68 km in 2002 and 2003. A total of 545 oocysts were dissected from 122 infected mosquitoes and genotyped at seven microsatellite markers. Five hundred and forty-seven mosquitoes, both infected and uninfected, were genotyped at eight microsatellites. For the parasite and the vector, the analysis revealed no (or very little) genetic differentiation among villages. This may be explained by high local population sizes for the parasite and the mosquito. The small level of genetic differentiation observed between populations may explain the speed at which antimalarial drug resistance and insecticide resistance spread into the African continent. PMID:18321750

  14. A novel Lie algebra of the genetic code over the Galois field of four DNA bases.

    PubMed

    Sánchez, Robersy; Grau, Ricardo; Morgado, Eberto

    2006-07-01

    Starting from the four DNA bases order in the Boolean lattice, a novel Lie Algebra of the genetic code is proposed. Here, the main partitions of the genetic code table were obtained as equivalent classes of quotient spaces of the genetic code vector space over the Galois field of the four DNA bases. The new algebraic structure shows strong connections among algebraic relationships, codon assignments and physicochemical properties of amino acids. Moreover, a distance defined between codons expresses a physicochemical meaning. It was also noticed that the distance between wild type and mutant codons tends to be small in mutational variants of four genes: human phenylalanine hydroxylase, human beta-globin, HIV-1 protease and HIV-1 reverse transcriptase. These results strongly suggest that deterministic rules in genetic code origin must be involved. PMID:16780898

  15. Protein Polymorphisms, Segregation in Genetic Crosses and Genetic Distances among Fishes of the Genus Xiphophorus (Poeciliidae)

    PubMed Central

    Morizot, Don C.; Siciliano, Michael J.

    1982-01-01

    The products of 49 protein-coding loci were examined by starch gel electrophoresis for populational variation in six species of Xiphophorus fishes and/or segregation in intra- and interspecific backcross and intercross hybrids. Electrophoretic variation was observed for 29 of the 35 locus products in a survey of 42 population samples. The highest frequency of polymorphic loci observed in noninbred populations was 0.143. After ten or more generations of inbreeding, all loci studied were monomorphic. Inbred strains generally exhibited the commonest electrophoretic alleles of the population from which they were derived. An assessment of genetic distances among Xiphophorus populations reflected classical systematic relationships and suggested incipient subspeciation between X. maculatus from different drainages as well as several species groups. Thirty-three loci were analyzed with respect to segregation in hybrids. The goodness of fit of segregations to Mendelian expectations at all loci analyzed (except loci in linkage group I) is interpreted as evidence for high genetic compatibility of the genomes of Xiphophorus species. It is anticipated that these data will result in a rapid expansion of the assignment of protein-coding loci to linkage groups in these lower vertebrate species. PMID:7173606

  16. Genetics of murine craniofacial morphology: diallel analysis of the eight founders of the Collaborative Cross.

    PubMed

    Percival, Christopher J; Liberton, Denise K; Pardo-Manuel de Villena, Fernando; Spritz, Richard; Marcucio, Ralph; Hallgrímsson, Benedikt

    2016-01-01

    Using eight inbred founder strains of the mouse Collaborative Cross (CC) project and their reciprocal F1 hybrids, we quantified variation in craniofacial morphology across mouse strains, explored genetic contributions to craniofacial variation that distinguish the founder strains, and tested whether specific or summary measures of craniofacial shape display stronger additive genetic contributions. This study thus provides critical information about phenotypic diversity among CC founder strains and about the genetic contributions to this phenotypic diversity, which is relevant to understanding the basis of variation in standard laboratory strains and natural populations. Craniofacial shape was quantified as a series of size-adjusted linear dimensions (RDs) and by principal components (PC) analysis of morphological landmarks captured from computed tomography images from 62 of the 64 reciprocal crosses of the CC founder strains. We first identified aspects of skull morphology that vary between these phenotypically 'normal' founder strains and that are defining characteristics of these strains. We estimated the contributions of additive and various non-additive genetic factors to phenotypic variation using diallel analyses of a subset of these strongly differing RDs and the first eight PCs of skull shape variation. We find little difference in the genetic contributions to RD measures and PC scores, suggesting fundamental similarities in the magnitude of genetic contributions to both specific and summary measures of craniofacial phenotypes. Our results indicate that there are stronger additive genetic effects associated with defining phenotypic characteristics of specific founder strains, suggesting these distinguishing measures are good candidates for use in genotype-phenotype association studies of CC mice. Our results add significantly to understanding of genotype-phenotype associations in the skull, which serve as a foundation for modeling the origins of medically

  17. GACD: Integrated Software for Genetic Analysis in Clonal F1 and Double Cross Populations.

    PubMed

    Zhang, Luyan; Meng, Lei; Wu, Wencheng; Wang, Jiankang

    2015-01-01

    Clonal species are common among plants. Clonal F1 progenies are derived from the hybridization between 2 heterozygous clones. In self- and cross-pollinated species, double crosses can be made from 4 inbred lines. A clonal F1 population can be viewed as a double cross population when the linkage phase is determined. The software package GACD (Genetic Analysis of Clonal F1 and Double cross) is freely available public software, capable of building high-density linkage maps and mapping quantitative trait loci (QTL) in clonal F1 and double cross populations. Three functionalities are integrated in GACD version 1.0: binning of redundant markers (BIN); linkage map construction (CDM); and QTL mapping (CDQ). Output of BIN can be directly used as input of CDM. After adding the phenotypic data, the output of CDM can be used as input of CDQ. Thus, GACD acts as a pipeline for genetic analysis. GACD and example datasets are freely available from www.isbreeding.net. PMID:26503825

  18. SPECIFIC AND CROSS-OVER EFFECTS OF FOAM ROLLING ON ANKLE DORSIFLEXION RANGE OF MOTION

    PubMed Central

    Beardsley, Chris

    2016-01-01

    ABSTRACT Background Flexibility is an important physical quality. Self-myofascial release (SMFR) methods such as foam rolling (FR) increase flexibility acutely but how long such increases in range of motion (ROM) last is unclear. Static stretching (SS) also increases flexibility acutely and produces a cross-over effect to contralateral limbs. FR may also produce a cross-over effect to contralateral limbs but this has not yet been identified. Purpose To explore the potential cross-over effect of SMFR by investigating the effects of a FR treatment on the ipsilateral limb of 3 bouts of 30 seconds on changes in ipsilateral and contralateral ankle DF ROM and to assess the time-course of those effects up to 20 minutes post-treatment. Methods A within- and between-subject design was carried out in a convenience sample of 26 subjects, allocated into FR (n=13) and control (CON, n=13) groups. Ankle DF ROM was recorded at baseline with the in-line weight-bearing lunge test for both ipsilateral and contralateral legs and at 0, 5, 10, 15, 20 minutes following either a two-minute seated rest (CON) or 3 3 30 seconds of FR of the plantar flexors of the dominant leg (FR). Repeated measures ANOVA was used to examine differences in ankle DF ROM. Results No significant between-group effect was seen following the intervention. However, a significant within-group effect (p<0.05) in the FR group was seen between baseline and all post-treatment time-points (0, 5, 10, 15 and 20 minutes). Significant within-group effects (p<0.05) were also seen in the ipsilateral leg between baseline and at all post-treatment time-points, and in the contralateral leg up to 10 minutes post-treatment, indicating the presence of a cross-over effect. Conclusions FR improves ankle DF ROM for at least 20 minutes in the ipsilateral limb and up to 10 minutes in the contralateral limb, indicating that FR produces a cross-over effect into the contralateral limb. The mechanism producing these cross-over effects is

  19. A portable expression resource for engineering cross-species genetic circuits and pathways

    PubMed Central

    Kushwaha, Manish; Salis, Howard M.

    2015-01-01

    Genetic circuits and metabolic pathways can be reengineered to allow organisms to process signals and manufacture useful chemicals. However, their functions currently rely on organism-specific regulatory parts, fragmenting synthetic biology and metabolic engineering into host-specific domains. To unify efforts, here we have engineered a cross-species expression resource that enables circuits and pathways to reuse the same genetic parts, while functioning similarly across diverse organisms. Our engineered system combines mixed feedback control loops and cross-species translation signals to autonomously self-regulate expression of an orthogonal polymerase without host-specific promoters, achieving nontoxic and tuneable gene expression in diverse Gram-positive and Gram-negative bacteria. Combining 50 characterized system variants with mechanistic modelling, we show how the cross-species expression resource's dynamics, capacity and toxicity are controlled by the control loops' architecture and feedback strengths. We also demonstrate one application of the resource by reusing the same genetic parts to express a biosynthesis pathway in both model and non-model hosts. PMID:26184393

  20. A portable expression resource for engineering cross-species genetic circuits and pathways.

    PubMed

    Kushwaha, Manish; Salis, Howard M

    2015-01-01

    Genetic circuits and metabolic pathways can be reengineered to allow organisms to process signals and manufacture useful chemicals. However, their functions currently rely on organism-specific regulatory parts, fragmenting synthetic biology and metabolic engineering into host-specific domains. To unify efforts, here we have engineered a cross-species expression resource that enables circuits and pathways to reuse the same genetic parts, while functioning similarly across diverse organisms. Our engineered system combines mixed feedback control loops and cross-species translation signals to autonomously self-regulate expression of an orthogonal polymerase without host-specific promoters, achieving nontoxic and tuneable gene expression in diverse Gram-positive and Gram-negative bacteria. Combining 50 characterized system variants with mechanistic modelling, we show how the cross-species expression resource's dynamics, capacity and toxicity are controlled by the control loops' architecture and feedback strengths. We also demonstrate one application of the resource by reusing the same genetic parts to express a biosynthesis pathway in both model and non-model hosts. PMID:26184393

  1. Cross-layer restoration with software defined networking based on IP over optical transport networks

    NASA Astrophysics Data System (ADS)

    Yang, Hui; Cheng, Lei; Deng, Junni; Zhao, Yongli; Zhang, Jie; Lee, Young

    2015-10-01

    The IP over optical transport network is a very promising networking architecture applied to the interconnection of geographically distributed data centers due to the performance guarantee of low delay, huge bandwidth and high reliability at a low cost. It can enable efficient resource utilization and support heterogeneous bandwidth demands in highly-available, cost-effective and energy-effective manner. In case of cross-layer link failure, to ensure a high-level quality of service (QoS) for user request after the failure becomes a research focus. In this paper, we propose a novel cross-layer restoration scheme for data center services with software defined networking based on IP over optical network. The cross-layer restoration scheme can enable joint optimization of IP network and optical network resources, and enhance the data center service restoration responsiveness to the dynamic end-to-end service demands. We quantitatively evaluate the feasibility and performances through the simulation under heavy traffic load scenario in terms of path blocking probability and path restoration latency. Numeric results show that the cross-layer restoration scheme improves the recovery success rate and minimizes the overall recovery time.

  2. Anomalous compressibility of ferropericlase throughout the iron spin cross-over

    PubMed Central

    Wentzcovitch, R. M.; Justo, J. F.; Wu, Z.; da Silva, C. R. S.; Yuen, D. A.; Kohlstedt, D.

    2009-01-01

    The thermoelastic properties of ferropericlase Mg1−xFexO (x = 0.1875) throughout the iron high-to-low spin cross-over have been investigated by first principles at Earth's lower mantle conditions. This cross-over has important consequences for elasticity such as an anomalous bulk modulus (KS) reduction. At room temperature the anomaly is somewhat sharp in pressure but broadens with increasing temperature. Along a typical geotherm it occurs across most of the lower mantle with a more significant KS reduction at ≈1,400–1,600 km depth. This anomaly might also cause a reduction in the effective activation energy for diffusion creep and lead to a viscosity minimum in the mid-lower mantle, in apparent agreement with results from inversion of data related with mantle convection and postglacial rebound. PMID:19439661

  3. Genetic impact dominates over environmental effects in development of carotid artery stiffness: a twin study.

    PubMed

    Horváth, Tamás; Osztovits, János; Pintér, Alexandra; Littvay, Levente; Cseh, Domonkos; Tárnoki, Adám D; Tárnoki, Dávid L; Jermendy, Adám L; Steinbach, Rita; Métneki, Júlia; Schillaci, Giuseppe; Kollai, Márk; Jermendy, György

    2014-01-01

    Arterial stiffness is an independent predictor of cardiovascular, cerebrovascular and all-cause mortality. Quantifying the genetic influence on the stiff arterial phenotype allows us to better predict the development of arterial stiffness. In this study, we aimed to determine the heritability of carotid artery stiffness in healthy twins. We studied 98 twin pairs of both sexes. We determined carotid artery stiffness locally using echo tracking and applanation tonometry. We estimated the heritability of stiffness parameters using structural equation modeling. The carotid distensibility coefficient showed the highest heritability (64%, 95% confidence interval 45-77%). The incremental elastic modulus, compliance and stiffness index β also showed substantial heritability (62%, 61% and 58%, respectively). The remaining 36-42% phenotypic variance was attributed to unshared environmental effects. Genetic influence appears to dominate over environmental factors in the development of carotid artery stiffness. Environmental factors may have an important role in favorably influencing the genetic predisposition for accelerated arterial stiffening. PMID:24089266

  4. Identification of genetic factors that modify motor performance and body weight using Collaborative Cross mice

    SciTech Connect

    Mao, Jian -Hua; Langley, Sasha A.; Huang, Yurong; Hang, Michael; Bouchard, Kristofer E.; Celniker, Susan E.; Brown, James B.; Jansson, Janet K.; Karpen, Gary H.; Snijders, Antoine M.

    2015-11-09

    Evidence has emerged that suggests a link between motor deficits, obesity and many neurological disorders. However, the contributing genetic risk factors are poorly understood. Here we used the Collaborative Cross (CC), a large panel of newly inbred mice that captures 90% of the known variation among laboratory mice, to identify the genetic loci controlling rotarod performance and its relationship with body weight in a cohort of 365 mice across 16 CC strains. Body weight and rotarod performance varied widely across CC strains and were significantly negatively correlated. Genetic linkage analysis identified 14 loci that were associated with body weight. However, 45 loci affected rotarod performance, seven of which were also associated with body weight, suggesting a strong link at the genetic level. As a result, we show that genes identified in this study overlap significantly with those related to neurological disorders and obesity found in human GWA studies. In conclusion, our results provide a genetic framework for studies of the connection between body weight, the central nervous system and behavior.

  5. Identification of genetic factors that modify motor performance and body weight using Collaborative Cross mice

    DOE PAGESBeta

    Mao, Jian -Hua; Langley, Sasha A.; Huang, Yurong; Hang, Michael; Bouchard, Kristofer E.; Celniker, Susan E.; Brown, James B.; Jansson, Janet K.; Karpen, Gary H.; Snijders, Antoine M.

    2015-11-09

    Evidence has emerged that suggests a link between motor deficits, obesity and many neurological disorders. However, the contributing genetic risk factors are poorly understood. Here we used the Collaborative Cross (CC), a large panel of newly inbred mice that captures 90% of the known variation among laboratory mice, to identify the genetic loci controlling rotarod performance and its relationship with body weight in a cohort of 365 mice across 16 CC strains. Body weight and rotarod performance varied widely across CC strains and were significantly negatively correlated. Genetic linkage analysis identified 14 loci that were associated with body weight. However,more » 45 loci affected rotarod performance, seven of which were also associated with body weight, suggesting a strong link at the genetic level. As a result, we show that genes identified in this study overlap significantly with those related to neurological disorders and obesity found in human GWA studies. In conclusion, our results provide a genetic framework for studies of the connection between body weight, the central nervous system and behavior.« less

  6. Effects of crossing distance and genetic relatedness on pollen performance in Alstroemeria aurea (Alstroemeriaceae).

    PubMed

    Souto, Cintia P; Aizen, Marcelo A; Premoli, Andrea C

    2002-03-01

    Prezygotic barriers may represent effective mechanisms to avoid the deleterious effects of inbreeding. This study reports the existence of distance-dependent prezygotic barriers in self-compatible Alstroemeria aurea, a clonal herb native to temperate forests of the southern Andes. We analyzed pollen germination and tube growth as indicators of donor-recipient affinity using crossing distances of 1, 10, and 100 m. We used allozyme electrophoresis to determine the actual genetic relatedness between donor and recipient ramets. Pollen germination was not affected by distance between mates, but the number of pollen tubes reaching the base of the style increased strongly with distance between donor and recipient. This pattern was related to an increase in genetic dissimilarity with distance between mates. In contrast, pollen tube-style interactions did not change with distance when we restricted analysis to individuals at different distances that appeared to be genetically identical. This test implied genetic dissimilarity as the critical factor affecting pollen performance. We propose that the existence of prezygotic barriers might contribute to the high degree of genetic mixing exhibited by some clonal species. PMID:21665638

  7. Identification of genetic factors that modify motor performance and body weight using Collaborative Cross mice

    PubMed Central

    Mao, Jian-Hua; Langley, Sasha A.; Huang, Yurong; Hang, Michael; Bouchard, Kristofer E.; Celniker, Susan E.; Brown, James B.; Jansson, Janet K.; Karpen, Gary H.; Snijders, Antoine M.

    2015-01-01

    Evidence has emerged that suggests a link between motor deficits, obesity and many neurological disorders. However, the contributing genetic risk factors are poorly understood. Here we used the Collaborative Cross (CC), a large panel of newly inbred mice that captures 90% of the known variation among laboratory mice, to identify the genetic loci controlling rotarod performance and its relationship with body weight in a cohort of 365 mice across 16 CC strains. Body weight and rotarod performance varied widely across CC strains and were significantly negatively correlated. Genetic linkage analysis identified 14 loci that were associated with body weight. However, 45 loci affected rotarod performance, seven of which were also associated with body weight, suggesting a strong link at the genetic level. Lastly, we show that genes identified in this study overlap significantly with those related to neurological disorders and obesity found in human GWA studies. In conclusion, our results provide a genetic framework for studies of the connection between body weight, the central nervous system and behavior. PMID:26548763

  8. Beliefs and attitudes towards participating in genetic research – a population based cross-sectional study

    PubMed Central

    2013-01-01

    Background Biobanks have the potential to offer a venue for chronic disease biomarker discovery, which would allow for disease early detection and for identification of carriers of a certain predictor biomarker. To assess the general attitudes towards genetic research and participation in biobanks in the Long Island/Queens area of New York, and what factors would predict a positive view of such research, participants from the NSLIJ hospital system were surveyed. Methods Participants were recruited at six hospital centers in the NSLIJ system during the summers of 2009 and again in 2011 (n = 1,041). Those who opted to participate were given a questionnaire containing 22 questions assessing demographics, lifestyle and attitudes towards genetic research. These questions addressed individual participant’s beliefs about the importance of genetic research, willingness to participate in genetic research themselves, and their views on informed consent issues. Results Respondents took a generally positive view of genetic research in general, as well as their own participation in such research. Those with reservations were most likely to cite concerns over the privacy of their medical and genetic information. Those who were married tended to view genetic research as important, while those in the younger age group viewed it as less important. Prior blood donation of respondents was found to be a predictor of their approval for genetic research. Demographic factors were not found to be predictive of personal willingness to participate in genetic research, or of approval for the opt-out approach to consent. Conclusions While respondents were generally inclined to approve of genetic research, and those who disapproved did not do so based on an underlying moral objection to such research, there is a disconnect between the belief in the importance of genetic research and the willingness of individuals to participate themselves. This indicates a continued concern for the ways

  9. Reducing cross-sectional data using a genetic algorithm method and effects on cross-section geometry and steady-flow profiles

    USGS Publications Warehouse

    Berenbrock, Charles E.

    2015-01-01

    The effects of reduced cross-sectional data points on steady-flow profiles were also determined. Thirty-five cross sections of the original steady-flow model of the Kootenai River were used. These two methods were tested for all cross sections with each cross section resolution reduced to 10, 20 and 30 data points, that is, six tests were completed for each of the thirty-five cross sections. Generally, differences from the original water-surface elevation were smaller as the number of data points in reduced cross sections increased, but this was not always the case, especially in the braided reach. Differences were smaller for reduced cross sections developed by the genetic algorithm method than the standard algorithm method.

  10. Cortisol reactivity to stress among youth: stability over time and genetic variants for stress sensitivity.

    PubMed

    Hankin, Benjamin L; Badanes, Lisa S; Smolen, Andrew; Young, Jami F

    2015-02-01

    Stress sensitivity may be one process that can explain why some genetically at-risk individuals are more susceptible to some types of stress-reactive psychopathologies. Dysregulation of the limbic-hypothalamic-pituitary-adrenal (LHPA) axis, including cortisol reactivity to challenge, represents a key aspect of stress sensitivity. However, the degree of stability over time among youth, especially differential stability as a function of particular genetic variants, has not been investigated. A general community sample of children and adolescents (mean age = 11.4; 56% girls) provided a DNA sample and completed 2 separate laboratory stress challenges, across an 18-month follow-up (N = 224 at Time 1; N = 194 at Time 2), with repeated measures of salivary cortisol. Results showed that test-retest stability for several indices of cortisol reactivity across the laboratory challenge visits were significant and of moderate magnitude for the whole sample. Moreover, gene variants of several biologically plausible systems relevant for stress sensitivity (especially 5-HTTLPR and CRHR1) demonstrated differential stability of cortisol reactivity over 18-months, such that carriers of genotypes conferring enhanced environmental susceptibility exhibited greater stability of cortisol levels over time for some LHPA axis indices. Findings suggest that LHPA axis dysregulation may exhibit some trait-like aspects underlying stress sensitivity in youth, especially for those who carry genes related to greater genetic susceptibility to environmental stress. PMID:25688432

  11. Antibody epitopes on g protein-coupled receptors mapped with genetically encoded photoactivatable cross-linkers.

    PubMed

    Ray-Saha, Sarmistha; Huber, Thomas; Sakmar, Thomas P

    2014-03-01

    We developed a strategy for creating epitope maps of monoclonal antibodies (mAbs) that bind to G protein-coupled receptors (GPCRs) containing photo-cross-linkers. Using human CXC chemokine receptor 4 (CXCR4) as a model system, we genetically incorporated the photolabile unnatural amino acid p-azido-l-phenylalanine (azF) at various positions within extracellular loop 2 (EC2). We then mapped the interactions of the azF-CXCR4 variants with mAb 12G5 using targeted loss-of-function studies and photo-cross-linking in whole cells in a microplate-based format. We used a novel variation of a whole cell enzyme-linked immunosorbent assay to quantitate cross-linking efficiency. 12G5 cross-linked primarily to residues 184, 178, and 189 in EC2 of CXCR4. Mapping of the data to the crystal structure of CXCR4 showed a distinct mAb epitope footprint with the photo-cross-linked residues clustered around the loss-of-function sites. We also used the targeted photo-cross-linking approach to study the interaction of human CC chemokine receptor 5 (CCR5) with PRO 140, a humanized mAb that inhibits human immunodeficiency virus-1 cellular entry, and 2D7. The mAbs produced distinct cross-linking patterns on EC2 of CCR5. PRO 140 cross-linked primarily to residues 174 and 175 at the amino-terminal end of EC2, and 2D7 cross-linked mainly to residues 170, 176, and 184. These results were mapped to the recent crystal structure of CCR5 in complex with maraviroc, showing cross-linked residues at the tip of the maraviroc binding crevice formed by EC2. As a strategy for mapping mAb epitopes on GPCRs, our targeted photo-cross-linking method is complementary to loss-of-function mutagenesis results and should be especially useful for studying mAbs with discontinuous epitopes. PMID:24490954

  12. A Genetic Test for Whether Pairs of Hermaphrodites Can Cross-Fertilize in a Selfing Killifish.

    PubMed

    Furness, Andrew I; Tatarenkov, Andrey; Avise, John C

    2015-01-01

    Kryptolebias marmoratus, a small killifish that lives in mangrove habitat from southern Florida to Brazil, is one of the planet's only known self-fertilizing hermaphroditic vertebrates. Generation after generation, hermaphroditic individuals simultaneously produce sperm and eggs and internally self-fertilize to produce what are, in effect, highly inbred clones of themselves. Although populations are composed primarily of hermaphrodites, they also contain some true males. The frequency of males in a population varies geographically, from <2% in Florida to as high as 25% in Belize. Males are known to mate occasionally with hermaphrodites, thereby releasing genetic variation that has profound consequences for population genetic structure. However, it is unknown whether hermaphrodites can or do sporadically mate with each other also. Here, we test whether hermaphroditic individuals of the killifish Kryptolebias marmoratus are capable of crossing with one another, in addition to their much more common habits of self-fertilization and occasional outcrossing with pure males. We employ an experimental design in which replicate hermaphrodite pairs were housed together and allowed to reproduce naturally. Among 173 embryos screened at diagnostic microsatellite loci, all were found to result from selfing (i.e., no embryos were the product of a hermaphrodite cross). We thus conclude that hermaphrodite pairs are unlikely to cross, or do so exceedingly rarely. PMID:26377993

  13. Modeling Host Genetic Regulation of Influenza Pathogenesis in the Collaborative Cross

    PubMed Central

    Ferris, Martin T.; Aylor, David L.; Bottomly, Daniel; Whitmore, Alan C.; Aicher, Lauri D.; Bell, Timothy A.; Bradel-Tretheway, Birgit; Bryan, Janine T.; Buus, Ryan J.; Gralinski, Lisa E.; Haagmans, Bart L.; McMillan, Leonard; Miller, Darla R.; Rosenzweig, Elizabeth; Valdar, William; Wang, Jeremy; Churchill, Gary A.; Threadgill, David W.; McWeeney, Shannon K.; Katze, Michael G.; Pardo-Manuel de Villena, Fernando; Baric, Ralph S.; Heise, Mark T.

    2013-01-01

    Genetic variation contributes to host responses and outcomes following infection by influenza A virus or other viral infections. Yet narrow windows of disease symptoms and confounding environmental factors have made it difficult to identify polymorphic genes that contribute to differential disease outcomes in human populations. Therefore, to control for these confounding environmental variables in a system that models the levels of genetic diversity found in outbred populations such as humans, we used incipient lines of the highly genetically diverse Collaborative Cross (CC) recombinant inbred (RI) panel (the pre-CC population) to study how genetic variation impacts influenza associated disease across a genetically diverse population. A wide range of variation in influenza disease related phenotypes including virus replication, virus-induced inflammation, and weight loss was observed. Many of the disease associated phenotypes were correlated, with viral replication and virus-induced inflammation being predictors of virus-induced weight loss. Despite these correlations, pre-CC mice with unique and novel disease phenotype combinations were observed. We also identified sets of transcripts (modules) that were correlated with aspects of disease. In order to identify how host genetic polymorphisms contribute to the observed variation in disease, we conducted quantitative trait loci (QTL) mapping. We identified several QTL contributing to specific aspects of the host response including virus-induced weight loss, titer, pulmonary edema, neutrophil recruitment to the airways, and transcriptional expression. Existing whole-genome sequence data was applied to identify high priority candidate genes within QTL regions. A key host response QTL was located at the site of the known anti-influenza Mx1 gene. We sequenced the coding regions of Mx1 in the eight CC founder strains, and identified a novel Mx1 allele that showed reduced ability to inhibit viral replication, while

  14. Genetic engineering in agriculture and corporate engineering in public debate: risk, public relations, and public debate over genetically modified crops.

    PubMed

    Patel, Rajeev; Torres, Robert J; Rosset, Peter

    2005-01-01

    Corporations have long influenced environmental and occupational health in agriculture, doing a great deal of damage, making substantial profits, and shaping public debate to make it appear that environmental misfortunes are accidents of an otherwise well-functioning system, rather than systemic. The debate over the genetically modified (GM) crops is an example. The largest producer of commercial GM seeds, Monsanto, exemplifies the industry's strategies: the invocation of poor people as beneficiaries, characterization of opposition as technophobic or anti-progress, and portrayal of their products as environmentally beneficial in the absence of or despite the evidence. This strategy is endemic to contemporary market capitalism, with its incentives to companies to externalize health and environmental costs to increase profits. PMID:16350477

  15. Using genetic information to test causal relationships in cross-sectional data

    PubMed Central

    Verhulst, Brad; Estabrook, Ryne

    2013-01-01

    Cross-sectional data from twins contain information that can be used to derive a test of causality between traits. This test of directionality is based upon the fact that genetic relationships between family members conform to an established structural pattern. In this paper we examine several common methods for empirically testing causality as well as several genetic models that we build on for the Direction of Causation (DoC) model. We then discuss the mathematical components of the DoC model and highlight limitations of the model and potential solutions to these limitations. We conclude by presenting an example from the personality and politics literature that has begun to explore the question whether or not personality traits cause people to hold specific political attitudes. PMID:23946557

  16. Increased frequency of mitotic crossing-over in heterochromatin during the first cleavage division in Drosophila melanogaster

    SciTech Connect

    Omel`yanchuk, L.V.; Volkova, E.I.

    1995-06-01

    It is shown that, although no compaction of paracentromeric heterochromatin occurs during the first cleavage division in Drosophila melanogaster, the frequency of mitotic crossing-over in corresponding chromosome regions is increased, as compared to that in euchromatin. Because a similar situation is observed at later stages of Drosophila development, at which compact chromatin regions become well-manifested, it is concluded that the effect of heterochromatin on the frequency of crossing-over does not depend on its packing. A positive correlation between crossing-over events in paracentromeric heterochromatin and euchromatin was observed. This effect is probably due to the formation of a continuous region of somatic synapsis, which facilitates the process of mitotic crossing-over. On this basis, it is proposed that the effect of heterochromatin on mitotic crossing-over is associated with preferential chromosome pairing in the corresponding regions. 10 refs., 1 fig.

  17. Population Genetic Structuring in Opisthorchis viverrini over Various Spatial Scales in Thailand and Lao PDR

    PubMed Central

    Laoprom, Nonglak; Sithithaworn, Paiboon; Andrews, Ross H.; Ando, Katsuhiko; Laha, Thewarach; Klinbunga, Sirawut; Webster, Joanne P.; Petney, Trevor N.

    2012-01-01

    Khon Kaen Province in northeast Thailand is known as a hot spot for opisthorchiasis in Southeast Asia. Preliminary allozyme and mitochondrial DNA haplotype data from within one endemic district in this Province (Ban Phai), indicated substantial genetic variability within Opisthorchis viverrini. Here, we used microsatellite DNA analyses to examine the genetic diversity and population structure of O. viverrini from four geographically close localities in Khon Kaen Province. Genotyping based on 12 microsatellite loci yielded a mean number of alleles per locus that ranged from 2.83 to 3.7 with an expected heterozygosity in Hardy–Weinberg equilibrium of 0.44–0.56. Assessment of population structure by pairwise FST analysis showed inter-population differentiation (P<0.05) which indicates population substructuring between these localities. Unique alleles were found in three of four localities with the highest number observed per locality being three. Our results highlight the existence of genetic diversity and population substructuring in O. viverrini over a small spatial scale which is similar to that found at a larger scale. This provides the basis for the investigation of the role of parasite genetic diversity and differentiation in transmission dynamics and control of O. viverrini. PMID:23166853

  18. Genetic diversity and population structure of Plasmodium falciparum over space and time in an African archipelago.

    PubMed

    Salgueiro, Patrícia; Vicente, José Luís; Figueiredo, Rita Carrilho; Pinto, João

    2016-09-01

    The archipelago of São Tomé and Principe (STP), West Africa, has suffered the heavy burden of malaria since the 16th century. Until the last decade, when after a successful control program STP has become a low transmission country and one of the few nations with decreases of more than 90% in malaria admission and death rates. We carried out a longitudinal study to determine the genetic structure of STP parasite populations over time and space. Twelve microsatellite loci were genotyped in Plasmodium falciparum samples from two islands collected in 1997, 2000 and 2004. Analysis was performed on proportions of mixed genotype infections, allelic diversity, population differentiation, effective population size and bottleneck effects. We have found high levels of genetic diversity and minimal inter-population genetic differentiation typical of African continental regions with intense and stable malaria transmission. We detected significant differences between the years, with special emphasis for 1997 that showed the highest proportion of samples infected with P. falciparum and the highest mean number of haplotypes per isolate. This study establishes a comprehensive genetic data baseline of a pre-intervention scenario for future studies; taking into account the most recent and successful control intervention on the territory. PMID:27262356

  19. Beliefs in genetic determinism and attitudes towards psychiatric genetic research: psychometric scale properties, construct associations, demographic correlates, and cross-cultural comparisons.

    PubMed

    Voracek, Martin; Swami, Viren; Loibl, Lisa Mariella; Furnham, Adrian

    2007-12-01

    Using two new scales, this study examined beliefs in genetic determinism and attitudes towards psychiatric genetic research in student samples from Austria, Malaysia, Romania, and the United Kingdom. For both constructs, effects of culture were detectable, whereas those related to key demographics were either small and inconsistent across samples (political orientation and religiosity) or zero (sex and age). Judged from factorial dimensionality and internal consistency, the psychometric properties of both scales were satisfactory. Belief in genetic determinism had lower prevalence and corresponded only modestly to positive attitudes towards psychiatric genetic research which had higher prevalence. The correlations of both constructs with a preference of inequality among social groups (social dominance orientation) were modest and inconsistent across samples. Both scales appear appropriate for cross-cultural applications, in particular for research into lay theories and public perceptions regarding genetic vs environmental effects on human behavior, mental disorders, and behavioral and psychiatric genetic research related to these. PMID:18232457

  20. Proton pump inhibitors and vascular function: A prospective cross-over pilot study

    PubMed Central

    Ghebremariam, Yohannes T.; Cooke, John P.; Khan, Fouzia; Thakker, Rahul N.; Chang, Peter; Shah, Nigam H.; Nead, Kevin T.; Leeper, Nicholas J.

    2015-01-01

    Background Proton pump inhibitors (PPIs) are commonly used drugs for the treatment of gastric reflux. Recent retrospective cohorts and large database studies have raised concern that the use of PPIs is associated with increased cardiovascular (CV) risk. However, there is no prospective clinical study evaluating whether the use of PPIs directly causes CV harm. Methods We conducted a controlled open-label cross-over pilot study among 21 adults aged 18 and older who are healthy (n = 11) or have established clinical cardiovascular disease (n = 10). Study subjects were assigned to receive a PPI (Prevacid; 30 mg) or a placebo pill once daily for 4 weeks. After a 2 week washout period, participants were crossed-over to receive the alternate treatment for the ensuing 4 weeks. Subjects underwent evaluation of vascular function (by the EndoPAT technique) and had plasma levels of asymmetric dimethylarginine (ADMA, an endogenous inhibitor of endothelial function previously implicated in PPI-mediated risk) measured prior to and after each treatment interval. Results We observed a marginal inverse correlation between the EndoPAT score and plasma levels of ADMA (r = −0.364). Subjects experienced a greater worsening in plasma ADMA levels while on PPI than on placebo, and this trend was more pronounced amongst those subjects with a history of vascular disease. However, these trends did not reach statistical significance, and PPI use was also not associated with an impairment in flow mediated vasodilation during the course of this study. Conclusions In this open-label, cross-over pilot study conducted among healthy subjects and coronary disease patients, PPI use did not significantly influence vascular endothelial function. Larger, long-term and blinded trials are needed to mechanistically explain the correlation between PPI use and adverse clinical outcomes, which has recently been reported in retrospective cohort studies. PMID:25835348

  1. Photosensitivity of germanosilicate fibres and preforms doped with nitrogen inhomogeneously over the cross section

    SciTech Connect

    Yatsenko, Yu P; Mashinsky, V M; Medvedkov, O I; Sazhin, O D; Dianov, Evgenii M; Khopin, V F; Vechkanov, N N; Gur'yanov, A N

    2003-03-31

    The effect of the inhomogeneous distribution of nitrogen impurity on the photosensitivity of germanosilicate fibres is studied. For this purpose, single-mode fibres with different alternations of the core layers sintered in nitrogen and oxygen atmospheres were specially prepared by the MCVD technique. Photoinduced variations in the quadratic nonlinear susceptibility and refractive index of these fibres were recorded. It is shown that the recording efficiency depends on the radial distribution of germanium oxygen-deficient centres, which can be controlled at the stage of sintering through a nonuniform doping by nitrogen over the cross-section. (fibre optics)

  2. Efficient replication of over 180 genetic associations with self-reported medical data.

    PubMed

    Tung, Joyce Y; Do, Chuong B; Hinds, David A; Kiefer, Amy K; Macpherson, J Michael; Chowdry, Arnab B; Francke, Uta; Naughton, Brian T; Mountain, Joanna L; Wojcicki, Anne; Eriksson, Nicholas

    2011-01-01

    While the cost and speed of generating genomic data have come down dramatically in recent years, the slow pace of collecting medical data for large cohorts continues to hamper genetic research. Here we evaluate a novel online framework for obtaining large amounts of medical information from a recontactable cohort by assessing our ability to replicate genetic associations using these data. Using web-based questionnaires, we gathered self-reported data on 50 medical phenotypes from a generally unselected cohort of over 20,000 genotyped individuals. Of a list of genetic associations curated by NHGRI, we successfully replicated about 75% of the associations that we expected to (based on the number of cases in our cohort and reported odds ratios, and excluding a set of associations with contradictory published evidence). Altogether we replicated over 180 previously reported associations, including many for type 2 diabetes, prostate cancer, cholesterol levels, and multiple sclerosis. We found significant variation across categories of conditions in the percentage of expected associations that we were able to replicate, which may reflect systematic inflation of the effects in some initial reports, or differences across diseases in the likelihood of misdiagnosis or misreport. We also demonstrated that we could improve replication success by taking advantage of our recontactable cohort, offering more in-depth questions to refine self-reported diagnoses. Our data suggest that online collection of self-reported data from a recontactable cohort may be a viable method for both broad and deep phenotyping in large populations. PMID:21858135

  3. [Genetic control of embryo lethality in crosses between common wheat and rye].

    PubMed

    Tikhenko, N D; Tsvetkova, N V; Voĭlokov, A V

    2005-08-01

    The phenotypic manifestation and genetic control of embryo lethality observed in crosses between common wheat and rye were studied. It was found that crosses between common wheat and inbred self-fertile rye lines L2 and 535 gave rise to ungerminating grains, in which the development and differentiation of the hybrid embryo are arrested. Study of the degree of embryo development in the hybrid grains obtained by crossing common wheat varieties with inbred rye lines L2 and 535 showed that genotypes of the parents affected the ratio between undifferentiated embryos of various sizes. Analysis of this trait was performed by test crosses according to a novel pedigree program with the use of interlinear hybrids and a set of fourth-generation hybrid recombinant inbred lines. Rye line L2 was shown to bear the Eml (Embryo lethality) gene, which terminates the development of the hybrid embryo in amphihaploids. The suggestion of complementary interaction between wheat and rye genes during formation of a "n ew" character in wheat-rye F1 hybrids is discussed. A method of detecting an allele not complementary to the rye Eml allele in wheat is proposed. The proposed test program allows appropriate study of the system of wheat and rye genes involved in complementary interaction in the genotype of a distant hybrid. PMID:16161628

  4. European Invasion of North American Pinus strobus at Large and Fine Scales: High Genetic Diversity and Fine-Scale Genetic Clustering over Time in the Adventive Range

    PubMed Central

    Mandák, Bohumil; Hadincová, Věroslava; Mahelka, Václav; Wildová, Radka

    2013-01-01

    Background North American Pinus strobus is a highly invasive tree species in Central Europe. Using ten polymorphic microsatellite loci we compared various aspects of the large-scale genetic diversity of individuals from 30 sites in the native distribution range with those from 30 sites in the European adventive distribution range. To investigate the ascertained pattern of genetic diversity of this intercontinental comparison further, we surveyed fine-scale genetic diversity patterns and changes over time within four highly invasive populations in the adventive range. Results Our data show that at the large scale the genetic diversity found within the relatively small adventive range in Central Europe, surprisingly, equals the diversity found within the sampled area in the native range, which is about thirty times larger. Bayesian assignment grouped individuals into two genetic clusters separating North American native populations from the European, non-native populations, without any strong genetic structure shown over either range. In the case of the fine scale, our comparison of genetic diversity parameters among the localities and age classes yielded no evidence of genetic diversity increase over time. We found that SGS differed across age classes within the populations under study. Old trees in general completely lacked any SGS, which increased over time and reached its maximum in the sapling stage. Conclusions Based on (1) the absence of difference in genetic diversity between the native and adventive ranges, together with the lack of structure in the native range, and (2) the lack of any evidence of any temporal increase in genetic diversity at four highly invasive populations in the adventive range, we conclude that population amalgamation probably first happened in the native range, prior to introduction. In such case, there would have been no need for multiple introductions from previously isolated populations, but only several introductions from

  5. Genetic Similarities between Compulsive Overeating and Addiction Phenotypes: A Case for "Food Addiction"?

    PubMed

    Carlier, Nina; Marshe, Victoria S; Cmorejova, Jana; Davis, Caroline; Müller, Daniel J

    2015-12-01

    There exists a continuous spectrum of overeating, where at the extremes there are casual overindulgences and at the other a 'pathological' drive to consume palatable foods. It has been proposed that pathological eating behaviors may be the result of addictive appetitive behavior and loss of ability to regulate the consumption of highly processed foods containing refined carbohydrates, fats, salt, and caffeine. In this review, we highlight the genetic similarities underlying substance addiction phenotypes and overeating compulsions seen in individuals with binge eating disorder. We relate these similarities to findings from neuroimaging studies on reward processing and clinical diagnostic criteria based on addiction phenotypes. The abundance of similarities between compulsive overeating and substance addictions puts forth a case for a 'food addiction' phenotype as a valid, diagnosable disorder. PMID:26478196

  6. “Slalom”: Microsurgical Cross-Over Decompression for Multilevel Degenerative Lumbar Stenosis

    PubMed Central

    2016-01-01

    Objective. Selective, bilateral multisegmental microsurgical decompression of lumbar spinal canal stenosis through separate, alternating cross-over approaches. Indications. Two-segmental and multisegmental degenerative central and lateral lumbar spinal stenosis. Contraindications. None. Surgical Technique. Minimally invasive, muscle, and facet joint-sparing bilateral decompression of the lumbar spinal canal through 2 or more alternating microsurgical cross-over approaches from one side. Results. From December 2010 until December 2015 we operated on 202 patients with 2 or multisegmental stenosis (115 f; 87 m; average age 69.3 yrs, range 51–91 yrs). All patients were suffering from symptoms typical of a degenerative lumbar spinal stenosis. All patients complained about back pain; however the leg symptoms were dominant in all cases. Per decompressed segment, the average OR time was 36 min and the blood loss 45.7 cc. Patients were mobilized 6 hrs postop and hospitalization averaged 5.9 days. A total of 116/202 patients did not need submuscular drainage. 27/202 patients suffered from a complication (13.4%). Dural tears occurred in 3.5%, an epidural hematoma in 5.5%, a deep wound infection in 1.98%, and a temporary radiculopathy postop in 1.5%. Postop follow-up ranged from 12 to 24 months. There was a significant improvement of EQ 5 D, Oswestry Disability Index (ODI), VAS for Back and Leg Pain, and preoperative standing times and walking distances. PMID:27504456

  7. Mammalian Reverse Genetics without Crossing Reveals Nr3a as a Short-Sleeper Gene.

    PubMed

    Sunagawa, Genshiro A; Sumiyama, Kenta; Ukai-Tadenuma, Maki; Perrin, Dimitri; Fujishima, Hiroshi; Ukai, Hideki; Nishimura, Osamu; Shi, Shoi; Ohno, Rei-ichiro; Narumi, Ryohei; Shimizu, Yoshihiro; Tone, Daisuke; Ode, Koji L; Kuraku, Shigehiro; Ueda, Hiroki R

    2016-01-26

    The identification of molecular networks at the system level in mammals is accelerated by next-generation mammalian genetics without crossing, which requires both the efficient production of whole-body biallelic knockout (KO) mice in a single generation and high-performance phenotype analyses. Here, we show that the triple targeting of a single gene using the CRISPR/Cas9 system achieves almost perfect KO efficiency (96%-100%). In addition, we developed a respiration-based fully automated non-invasive sleep phenotyping system, the Snappy Sleep Stager (SSS), for high-performance (95.3% accuracy) sleep/wake staging. Using the triple-target CRISPR and SSS in tandem, we reliably obtained sleep/wake phenotypes, even in double-KO mice. By using this system to comprehensively analyze all of the N-methyl-D-aspartate (NMDA) receptor family members, we found Nr3a as a short-sleeper gene, which is verified by an independent set of triple-target CRISPR. These results demonstrate the application of mammalian reverse genetics without crossing to organism-level systems biology in sleep research. PMID:26774482

  8. Estimating effective population size and migration rates from genetic samples over space and time.

    PubMed Central

    Wang, Jinliang; Whitlock, Michael C

    2003-01-01

    In the past, moment and likelihood methods have been developed to estimate the effective population size (N(e)) on the basis of the observed changes of marker allele frequencies over time, and these have been applied to a large variety of species and populations. Such methods invariably make the critical assumption of a single isolated population receiving no immigrants over the study interval. For most populations in the real world, however, migration is not negligible and can substantially bias estimates of N(e) if it is not accounted for. Here we extend previous moment and maximum-likelihood methods to allow the joint estimation of N(e) and migration rate (m) using genetic samples over space and time. It is shown that, compared to genetic drift acting alone, migration results in changes in allele frequency that are greater in the short term and smaller in the long term, leading to under- and overestimation of N(e), respectively, if it is ignored. Extensive simulations are run to evaluate the newly developed moment and likelihood methods, which yield generally satisfactory estimates of both N(e) and m for populations with widely different effective sizes and migration rates and patterns, given a reasonably large sample size and number of markers. PMID:12586728

  9. Mathematical model of adult stem cell regeneration with cross-talk between genetic and epigenetic regulation

    PubMed Central

    Lei, Jinzhi; Levin, Simon A.; Nie, Qing

    2014-01-01

    Adult stem cells, which exist throughout the body, multiply by cell division to replenish dying cells or to promote regeneration to repair damaged tissues. To perform these functions during the lifetime of organs or tissues, stem cells need to maintain their populations in a faithful distribution of their epigenetic states, which are susceptible to stochastic fluctuations during each cell division, unexpected injury, and potential genetic mutations that occur during many cell divisions. However, it remains unclear how the three processes of differentiation, proliferation, and apoptosis in regulating stem cells collectively manage these challenging tasks. Here, without considering molecular details, we propose a genetic optimal control model for adult stem cell regeneration that includes the three fundamental processes, along with cell division and adaptation based on differential fitnesses of phenotypes. In the model, stem cells with a distribution of epigenetic states are required to maximize expected performance after each cell division. We show that heterogeneous proliferation that depends on the epigenetic states of stem cells can improve the maintenance of stem cell distributions to create balanced populations. A control strategy during each cell division leads to a feedback mechanism involving heterogeneous proliferation that can accelerate regeneration with less fluctuation in the stem cell population. When mutation is allowed, apoptosis evolves to maximize the performance during homeostasis after multiple cell divisions. The overall results highlight the importance of cross-talk between genetic and epigenetic regulation and the performance objectives during homeostasis in shaping a desirable heterogeneous distribution of stem cells in epigenetic states. PMID:24501127

  10. Attitudes to genetically modified food over time: How trust in organizations and the media cycle predict support.

    PubMed

    Marques, Mathew D; Critchley, Christine R; Walshe, Jarrod

    2015-07-01

    This research examined public opinion toward genetically modified plants and animals for food, and how trust in organizations and media coverage explained attitudes toward these organisms. Nationally representative samples (N=8821) over 10 years showed Australians were less positive toward genetically modified animals compared to genetically modified plants for food, especially in years where media coverage was high. Structural equation modeling found that positive attitudes toward different genetically modified organisms for food were significantly associated with higher trust in scientists and regulators (e.g. governments), and with lower trust in watchdogs (e.g. environmental movement). Public trust in scientists and watchdogs was a stronger predictor of attitudes toward the use of genetically modified plants for food than animals, but only when media coverage was low. Results are discussed regarding the moral acceptability of genetically modified organisms for food, the media's role in shaping public opinion, and the role public trust in organizations has on attitudes toward genetically modified organisms. PMID:25063421

  11. A cross-species genetic analysis identifies candidate genes for mouse anxiety and human bipolar disorder.

    PubMed

    Ashbrook, David G; Williams, Robert W; Lu, Lu; Hager, Reinmar

    2015-01-01

    Bipolar disorder (BD) is a significant neuropsychiatric disorder with a lifetime prevalence of ~1%. To identify genetic variants underlying BD genome-wide association studies (GWAS) have been carried out. While many variants of small effect associated with BD have been identified few have yet been confirmed, partly because of the low power of GWAS due to multiple comparisons being made. Complementary mapping studies using murine models have identified genetic variants for behavioral traits linked to BD, often with high power, but these identified regions often contain too many genes for clear identification of candidate genes. In the current study we have aligned human BD GWAS results and mouse linkage studies to help define and evaluate candidate genes linked to BD, seeking to use the power of the mouse mapping with the precision of GWAS. We use quantitative trait mapping for open field test and elevated zero maze data in the largest mammalian model system, the BXD recombinant inbred mouse population, to identify genomic regions associated with these BD-like phenotypes. We then investigate these regions in whole genome data from the Psychiatric Genomics Consortium's bipolar disorder GWAS to identify candidate genes associated with BD. Finally we establish the biological relevance and pathways of these genes in a comprehensive systems genetics analysis. We identify four genes associated with both mouse anxiety and human BD. While TNR is a novel candidate for BD, we can confirm previously suggested associations with CMYA5, MCTP1, and RXRG. A cross-species, systems genetics analysis shows that MCTP1, RXRG, and TNR coexpress with genes linked to psychiatric disorders and identify the striatum as a potential site of action. CMYA5, MCTP1, RXRG, and TNR are associated with mouse anxiety and human BD. We hypothesize that MCTP1, RXRG, and TNR influence intercellular signaling in the striatum. PMID:26190982

  12. A cross-species genetic analysis identifies candidate genes for mouse anxiety and human bipolar disorder

    PubMed Central

    Ashbrook, David G.; Williams, Robert W.; Lu, Lu; Hager, Reinmar

    2015-01-01

    Bipolar disorder (BD) is a significant neuropsychiatric disorder with a lifetime prevalence of ~1%. To identify genetic variants underlying BD genome-wide association studies (GWAS) have been carried out. While many variants of small effect associated with BD have been identified few have yet been confirmed, partly because of the low power of GWAS due to multiple comparisons being made. Complementary mapping studies using murine models have identified genetic variants for behavioral traits linked to BD, often with high power, but these identified regions often contain too many genes for clear identification of candidate genes. In the current study we have aligned human BD GWAS results and mouse linkage studies to help define and evaluate candidate genes linked to BD, seeking to use the power of the mouse mapping with the precision of GWAS. We use quantitative trait mapping for open field test and elevated zero maze data in the largest mammalian model system, the BXD recombinant inbred mouse population, to identify genomic regions associated with these BD-like phenotypes. We then investigate these regions in whole genome data from the Psychiatric Genomics Consortium's bipolar disorder GWAS to identify candidate genes associated with BD. Finally we establish the biological relevance and pathways of these genes in a comprehensive systems genetics analysis. We identify four genes associated with both mouse anxiety and human BD. While TNR is a novel candidate for BD, we can confirm previously suggested associations with CMYA5, MCTP1, and RXRG. A cross-species, systems genetics analysis shows that MCTP1, RXRG, and TNR coexpress with genes linked to psychiatric disorders and identify the striatum as a potential site of action. CMYA5, MCTP1, RXRG, and TNR are associated with mouse anxiety and human BD. We hypothesize that MCTP1, RXRG, and TNR influence intercellular signaling in the striatum. PMID:26190982

  13. SPECIFIC AND CROSS OVER EFFECTS OF MASSAGE FOR MUSCLE SORENESS: RANDOMIZED CONTROLLED TRIAL

    PubMed Central

    Sundstrup, Emil; Søndergaard, Stine D.; Behm, David; Brandt, Mikkel; Særvoll, Charlotte A.; Jakobsen, Markus D.; Andersen, Lars L.

    2014-01-01

    Purpose/Background: Muscle soreness can negatively interfere with the activities of daily living as well as sports performance. In the working environment, a common problem is muscle tenderness, soreness and pain, especially for workers frequently exposed to unilateral high repetitive movements tasks. The aim of the study is therefore to investigate the acute effect of massage applied using a simple device Thera‐band roller Massager on laboratory induced hamstring muscle soreness, and the potential cross over effect to the non‐massaged limb. Methods: 22 healthy untrained men (Mean age 34 +/− 7 years; mean height 181.7 +/− 6.9 cm; mean weight 80.6 +/− 6.4 kg; BMI: 24.5 +/− 1.3) with no prior history of knee, low back or neck injury or other adverse health issues were recruited. Participants visited the researchers on two separate occasions, separated by 48 hours, each time providing a soreness rating (modified visual analog scale 0‐10), and being tested for pressure pain threshold (PPT) and active range of motion (ROM) of the hamstring muscles. During the first visit, delayed onset muscular soreness of the hamstring muscles was induced by 10 x 10 repetitions of the stiff‐legged dead‐lift. On the second visit participants received either 1) 10 minutes of roller massage on one leg, while the contralateral leg served as a cross over control, or 2) Resting for 10 minutes with no massage at all. Measurement of soreness, PPT and ROM were taken immediately before and at 0, 10, 30 and 60 min. after treatment. Results: There was a significant group by time interaction for soreness (p < 0.0001) and PPT (p = 0.0007), with the massage group experiencing reduced soreness and increasing PPT compared with the control group. There was no group by time interaction for ROM (p = 0.18). At 10 min. post massage there was a significant reduction in soreness of the non‐massaged limb in the cross over control group compared to controls but this effect was lost 30

  14. Ecological change predicts population dynamics and genetic diversity over 120 000 years.

    PubMed

    Horreo, Jose Luis; Jiménez-Valverde, Alberto; Fitze, Patrick S

    2016-05-01

    While ecological effects on short-term population dynamics are well understood, their effects over millennia are difficult to demonstrate and convincing evidence is scant. Using coalescent methods, we analysed past population dynamics of three lizard species (Psammodromus hispanicus, P. edwardsianus, P. occidentalis) and linked the results with climate change data covering the same temporal horizon (120 000 years). An increase in population size over time was observed in two species, and in P. occidentalis, no change was observed. Temporal changes in temperature seasonality and the maximum temperature of the warmest month were congruent with changes in population dynamics observed for the three species and both variables affected population density, either directly or indirectly (via a life-history trait). These results constitute the first solid link between ecological change and long-term population dynamics. The results moreover suggest that ecological change leaves genetic signatures that can be retrospectively traced, providing evidence that ecological change is a crucial driver of genetic diversity and speciation. PMID:26666533

  15. Molecular-scale dynamics of light-induced spin cross-over in a two-dimensional layer

    NASA Astrophysics Data System (ADS)

    Bairagi, Kaushik; Iasco, Olga; Bellec, Amandine; Kartsev, Alexey; Li, Dongzhe; Lagoute, Jérôme; Chacon, Cyril; Girard, Yann; Rousset, Sylvie; Miserque, Frédéric; Dappe, Yannick J.; Smogunov, Alexander; Barreteau, Cyrille; Boillot, Marie-Laure; Mallah, Talal; Repain, Vincent

    2016-07-01

    Spin cross-over molecules show the unique ability to switch between two spin states when submitted to external stimuli such as temperature, light or voltage. If controlled at the molecular scale, such switches would be of great interest for the development of genuine molecular devices in spintronics, sensing and for nanomechanics. Unfortunately, up to now, little is known on the behaviour of spin cross-over molecules organized in two dimensions and their ability to show cooperative transformation. Here we demonstrate that a combination of scanning tunnelling microscopy measurements and ab initio calculations allows discriminating unambiguously between both states by local vibrational spectroscopy. We also show that a single layer of spin cross-over molecules in contact with a metallic surface displays light-induced collective processes between two ordered mixed spin-state phases with two distinct timescale dynamics. These results open a way to molecular scale control of two-dimensional spin cross-over layers.

  16. Molecular-scale dynamics of light-induced spin cross-over in a two-dimensional layer.

    PubMed

    Bairagi, Kaushik; Iasco, Olga; Bellec, Amandine; Kartsev, Alexey; Li, Dongzhe; Lagoute, Jérôme; Chacon, Cyril; Girard, Yann; Rousset, Sylvie; Miserque, Frédéric; Dappe, Yannick J; Smogunov, Alexander; Barreteau, Cyrille; Boillot, Marie-Laure; Mallah, Talal; Repain, Vincent

    2016-01-01

    Spin cross-over molecules show the unique ability to switch between two spin states when submitted to external stimuli such as temperature, light or voltage. If controlled at the molecular scale, such switches would be of great interest for the development of genuine molecular devices in spintronics, sensing and for nanomechanics. Unfortunately, up to now, little is known on the behaviour of spin cross-over molecules organized in two dimensions and their ability to show cooperative transformation. Here we demonstrate that a combination of scanning tunnelling microscopy measurements and ab initio calculations allows discriminating unambiguously between both states by local vibrational spectroscopy. We also show that a single layer of spin cross-over molecules in contact with a metallic surface displays light-induced collective processes between two ordered mixed spin-state phases with two distinct timescale dynamics. These results open a way to molecular scale control of two-dimensional spin cross-over layers. PMID:27425776

  17. Molecular-scale dynamics of light-induced spin cross-over in a two-dimensional layer

    PubMed Central

    Bairagi, Kaushik; Iasco, Olga; Bellec, Amandine; Kartsev, Alexey; Li, Dongzhe; Lagoute, Jérôme; Chacon, Cyril; Girard, Yann; Rousset, Sylvie; Miserque, Frédéric; Dappe, Yannick J; Smogunov, Alexander; Barreteau, Cyrille; Boillot, Marie-Laure; Mallah, Talal; Repain, Vincent

    2016-01-01

    Spin cross-over molecules show the unique ability to switch between two spin states when submitted to external stimuli such as temperature, light or voltage. If controlled at the molecular scale, such switches would be of great interest for the development of genuine molecular devices in spintronics, sensing and for nanomechanics. Unfortunately, up to now, little is known on the behaviour of spin cross-over molecules organized in two dimensions and their ability to show cooperative transformation. Here we demonstrate that a combination of scanning tunnelling microscopy measurements and ab initio calculations allows discriminating unambiguously between both states by local vibrational spectroscopy. We also show that a single layer of spin cross-over molecules in contact with a metallic surface displays light-induced collective processes between two ordered mixed spin-state phases with two distinct timescale dynamics. These results open a way to molecular scale control of two-dimensional spin cross-over layers. PMID:27425776

  18. [Intraluminal Aspect of Femoro-femoral Cross-over Bypass Graft Mimics Bladder Stone].

    PubMed

    Sonak, I; Wiedemann, A; Heppner, H J

    2016-04-01

    Iatrogenic bladder perforation with delayed diagnosis and treatment in the context of the placement of a vascular prosthesis, e. g. a femoro-femoral cross-over bypass graft, is extremely rare. This is emphasised by the present publication, which is the second published case study worldwide. To identify such a situation is very important because there is a risk of inappropriate treatment if such a bypass complication remains undetected, and the potential complications of an improperly intended "treatment of a bladder stone" may be deleterious or even lethal. Therefore, the involved disciplines should be aware of this possibility in order to initiate relevant diagnostic measures, especially diagnostic cystoscopy, without any delay if symptoms such as voiding disorders or alguria coincide with vascular bypass grafting. PMID:26881873

  19. Flunarizine-pizotifen single-dose double-blind cross-over trial in migraine prophylaxis.

    PubMed

    Cerbo, R; Casacchia, M; Formisano, R; Feliciani, M; Cusimano, G; Buzzi, M G; Agnoli, A

    1986-03-01

    The results of a double-blind cross-over clinical trial involving 27 patients with classical or common migraine are described to compare the prophylactic effect of the calcium entry blocker flunarizine with that of pizotifen. Duration of the treatment was two months, with an evening single-dose administration of both drugs. For most parameters, there was no definite difference between flunarizine and pizotifen in migraine prophylaxis. It has been demonstrated previously that pizotifen is an effective drug in migraine prophylaxis, and these results suggest that flunarizine is effective, too. Weight gain as a side effect was less frequent and less severe with flunarizine than with pizotifen; other side effects showed the same incidence with both drugs. PMID:3516406

  20. Quantitative study of ruthenium cross-over in direct methanol fuel cells during early operation hours

    NASA Astrophysics Data System (ADS)

    Schoekel, A.; Melke, J.; Bruns, M.; Wippermann, K.; Kuppler, F.; Roth, C.

    2016-01-01

    In direct methanol fuel cells (DMFC), ruthenium cross-over is an important degradation phenomenon. The loss of ruthenium from the anode, its transport through the membrane and its deposition onto the cathode are detrimental to the fuel cell performance and limit the fuel cell's lifetime. Here we present a quantitative study on the fraction of ruthenium being transferred from the anode to the cathode during early operation hours (0-100 h) of a DMFC. Already during fabrication of the MEA ruthenium is transferred to the cathode. In our pristine MEAs about 0.024 wt% Ru could be found in the cathode catalyst. The cell potential during operation seems to have only a minor influence on the dissolution process. In contrast, the operation time appears to be much more important. Our data hint at two dissolution processes: a fast process dominating the first hours of operation and a slower process, which is responsible for the ongoing ruthenium transfer during the fuel cell lifetime. After 2 h held at open circuit conditions the Ru content of the cathode side was 10 times higher than in the pristine MEA. In contrast, the slower process increased that amount only by a factor of two over the course of another 100 h.

  1. Eulerian models for particle trajectory crossing in turbulent flows over a large range of Stokes numbers

    NASA Astrophysics Data System (ADS)

    Fox, Rodney O.; Vie, Aymeric; Laurent, Frederique; Chalons, Christophe; Massot, Marc

    2012-11-01

    Numerous applications involve a disperse phase carried by a gaseous flow. To simulate such flows, one can resort to a number density function (NDF) governed a kinetic equation. Traditionally, Lagrangian Monte-Carlo methods are used to solve for the NDF, but are expensive as the number of numerical particles needed must be large to control statistical errors. Moreover, such methods are not well adapted to high-performance computing because of the intrinsic inhomogeneity of the NDF. To overcome these issues, Eulerian methods can be used to solve for the moments of the NDF resulting in an unclosed Eulerian system of hyperbolic conservation laws. To obtain closure, in this work a multivariate bi-Gaussian quadrature is used, which can account for particle trajectory crossing (PTC) over a large range of Stokes numbers. This closure uses up to four quadrature points in 2-D velocity phase space to capture large-scale PTC, and an anisotropic Gaussian distribution around each quadrature point to model small-scale PTC. Simulations of 2-D particle-laden isotropic turbulence at different Stokes numbers are employed to validate the Eulerian models against results from the Lagrangian approach. Good agreement is found for the number density fields over the entire range of Stokes numbers tested. Research carried out at the Center for Turbulence Research 2012 Summer Program.

  2. Combining ability analysis over F1-F 5 generations in diallel crosses of bread wheat.

    PubMed

    Bhullar, G S; Gill, K S; Khehra, A S

    1979-03-01

    Combining ability studies for grain yield and its primary component traits in diallel crosses involving seven diverse wheat cultivars of bread wheat (Triticum aestivum L.) over generations F1-F5 are reported. The general and specific combining ability variances were significant in all generations for all the traits except specific combining ability variance for number of spikes per plant in the F5. The ratio of general to specific combining ability variances was significant for all the traits except grain yield in all the generations. This indicated an equal role of additive and non-additive gene effects in the inheritance of grain yield, and the predominance of the former for its component traits. The presence of significant specific combining ability variances in even the advanced generations may be the result of an additive x additive type of epistasis or evolutionary divergence among progenies in the same parental array. The relative breeding values of the parental varieties, as indicated by their general combining ability effects, did not vary much over the generations. The cheap and reliable procedure observed for making the choice of parents, selecting hybrids and predicting advanced generation (F5) bulk hybrid performance was the determination of breeding values of the parents on the relative performance of their F2 progeny bulks. PMID:24306488

  3. Limitations to estimating bacterial cross-speciestransmission using genetic and genomic markers: inferencesfrom simulation modeling

    USGS Publications Warehouse

    Julio Andre, Benavides; Cross, Paul C.; Luikart, Gordon; Scott, Creel

    2014-01-01

    Cross-species transmission (CST) of bacterial pathogens has major implications for human health, livestock, and wildlife management because it determines whether control actions in one species may have subsequent effects on other potential host species. The study of bacterial transmission has benefitted from methods measuring two types of genetic variation: variable number of tandem repeats (VNTRs) and single nucleotide polymorphisms (SNPs). However, it is unclear whether these data can distinguish between different epidemiological scenarios. We used a simulation model with two host species and known transmission rates (within and between species) to evaluate the utility of these markers for inferring CST. We found that CST estimates are biased for a wide range of parameters when based on VNTRs and a most parsimonious reconstructed phylogeny. However, estimations of CST rates lower than 5% can be achieved with relatively low bias using as low as 250 SNPs. CST estimates are sensitive to several parameters, including the number of mutations accumulated since introduction, stochasticity, the genetic difference of strains introduced, and the sampling effort. Our results suggest that, even with whole-genome sequences, unbiased estimates of CST will be difficult when sampling is limited, mutation rates are low, or for pathogens that were recently introduced.

  4. A reciprocal cross design to map the genetic architecture of complex traits in apomictic plants.

    PubMed

    Yin, Danni; Zhu, Xuli; Jiang, Libo; Zhang, Jian; Zeng, Yanru; Wu, Rongling

    2015-02-01

    Many higher plants of economic and biological importance undergo apomixis in which the maternal tissue of the ovule forms a seed, without experiencing meiosis and fertilization. This feature of apomixis has made it difficult to perform linkage mapping which relies on meiotic recombination. Here, we describe a computational model for mapping quantitative trait loci (QTLs) that control complex traits in apomictic plants. The model is founded on the mixture model-based likelihood in which maternal genotypes are dissolved into two possible components generated by meiotic and apomictic processes, respectively. The EM algorithm was implemented to discern meiotic and apomictic genotypes and, therefore, allow the marker-QTL linkage relationship to be estimated. By capitalizing on reciprocal crosses, the model is renovated to estimate and test imprinting effects of QTLs, providing a better gateway to characterize the genetic architecture of complex traits. The model was validated through computer simulation and further demonstrated for its usefulness by analyzing a real data for an apomictic woody plant. The model has for the first time provided a unique tool for genetic mapping in apomictic plants. PMID:25354995

  5. Genetic analysis of carbon isotope discrimination and agronomic characters in a bread wheat cross.

    PubMed

    Ehdaie, B; Waines, J G

    1994-09-01

    Carbon isotope discrimination (Δ) has been suggested as a selection criterion to improve transpiration efficiency (W) in bread wheat (Triticum aestivum L.). Cultivars 'Chinese Spring' with low A (high W) and 'Yecora Rojo' with high Δ (low W) were crossed to develop F1, F2, BC1, and BC2 populations for genetic analysis of Δ and other agronomic characters under well-watered (wet) and water-stressed (dry) field conditions. Significant variation was observed among the generations for Δ only under the wet environment. Generation x irrigation interactions were not significant for Δ. Generation means analysis indicated that additive gene action is of primary importance in the expression of Δ under nonstress conditions. Dominance gene action was also detected for Δ, and the direction of dominance was toward higher values of Δ. The broad-sense and the narrow-sense heritabilities for Δ were 61 % and 57% under the wet conditions, but were 48% and 12% under the draughted conditions, respectively. The narrow-sense heritabilities for grain yield, above-ground dry matter, and harvest index were 36%, 39%, and 60% under the wet conditions and 21%, 44%, and 20% under dry conditions, respectively. The significant additive genetic variation and moderate estimate of the narrow-sense heritability observed for Δ indicated that selection under wet environments should be effective in changing Δ in spring bread wheat. PMID:24186257

  6. Genetic analysis of dyslexia candidate genes in the European cross-linguistic NeuroDys cohort.

    PubMed

    Becker, Jessica; Czamara, Darina; Scerri, Tom S; Ramus, Franck; Csépe, Valéria; Talcott, Joel B; Stein, John; Morris, Andrew; Ludwig, Kerstin U; Hoffmann, Per; Honbolygó, Ferenc; Tóth, Dénes; Fauchereau, Fabien; Bogliotti, Caroline; Iannuzzi, Stéphanie; Chaix, Yves; Valdois, Sylviane; Billard, Catherine; George, Florence; Soares-Boucaud, Isabelle; Gérard, Christophe-Loïc; van der Mark, Sanne; Schulz, Enrico; Vaessen, Anniek; Maurer, Urs; Lohvansuu, Kaisa; Lyytinen, Heikki; Zucchelli, Marco; Brandeis, Daniel; Blomert, Leo; Leppänen, Paavo H T; Bruder, Jennifer; Monaco, Anthony P; Müller-Myhsok, Bertram; Kere, Juha; Landerl, Karin; Nöthen, Markus M; Schulte-Körne, Gerd; Paracchini, Silvia; Peyrard-Janvid, Myriam; Schumacher, Johannes

    2014-05-01

    Dyslexia is one of the most common childhood disorders with a prevalence of around 5-10% in school-age children. Although an important genetic component is known to have a role in the aetiology of dyslexia, we are far from understanding the molecular mechanisms leading to the disorder. Several candidate genes have been implicated in dyslexia, including DYX1C1, DCDC2, KIAA0319, and the MRPL19/C2ORF3 locus, each with reports of both positive and no replications. We generated a European cross-linguistic sample of school-age children - the NeuroDys cohort - that includes more than 900 individuals with dyslexia, sampled with homogenous inclusion criteria across eight European countries, and a comparable number of controls. Here, we describe association analysis of the dyslexia candidate genes/locus in the NeuroDys cohort. We performed both case-control and quantitative association analyses of single markers and haplotypes previously reported to be dyslexia-associated. Although we observed association signals in samples from single countries, we did not find any marker or haplotype that was significantly associated with either case-control status or quantitative measurements of word-reading or spelling in the meta-analysis of all eight countries combined. Like in other neurocognitive disorders, our findings underline the need for larger sample sizes to validate possibly weak genetic effects. PMID:24022301

  7. Soil water capture trends over 50 years of single-cross maize (Zea mays L.) breeding in the US corn-belt.

    PubMed

    Reyes, Andres; Messina, Carlos D; Hammer, Graeme L; Liu, Lu; van Oosterom, Erik; Lafitte, Renee; Cooper, Mark

    2015-12-01

    Breeders have successfully improved maize (Zea mays L.) grain yield for the conditions of the US corn-belt over the past 80 years, with the past 50 years utilizing single-cross hybrids. Long-term improvement for grain yield under water-limited conditions has also been reported. Grain yield under water-limited conditions depends on water use, water use efficiency, and harvest index. It has been hypothesized that long-term genetic gain for yield could be due, in part, to increased water capture from the soil. This hypothesis was tested using a set of elite single-cross hybrids that were released by DuPont Pioneer between 1963 and 2009. Eighteen hybrids were grown in the field during 2010 and 2011 growing seasons at Woodland, CA, USA. Crops grew predominantly on stored soil water and drought stress increased as the season progressed. Soil water content was measured to 300cm depth throughout the growing season. Significant water extraction occurred to a depth of 240-300cm and seasonal water use was calculated from the change in soil water over this rooting zone. Grain yield increased significantly with year of commercialization, but no such trend was observed for total water extraction. Therefore, the measured genetic gain for yield for the period represented by this set of hybrids must be related to either increased efficiency of water use or increased carbon partitioning to the grain, rather than increased soil water uptake. PMID:26428065

  8. Soil water capture trends over 50 years of single-cross maize (Zea mays L.) breeding in the US corn-belt

    PubMed Central

    Reyes, Andres; Messina, Carlos D.; Hammer, Graeme L.; Liu, Lu; van Oosterom, Erik; Lafitte, Renee; Cooper, Mark

    2015-01-01

    Breeders have successfully improved maize (Zea mays L.) grain yield for the conditions of the US corn-belt over the past 80 years, with the past 50 years utilizing single-cross hybrids. Long-term improvement for grain yield under water-limited conditions has also been reported. Grain yield under water-limited conditions depends on water use, water use efficiency, and harvest index. It has been hypothesized that long-term genetic gain for yield could be due, in part, to increased water capture from the soil. This hypothesis was tested using a set of elite single-cross hybrids that were released by DuPont Pioneer between 1963 and 2009. Eighteen hybrids were grown in the field during 2010 and 2011 growing seasons at Woodland, CA, USA. Crops grew predominantly on stored soil water and drought stress increased as the season progressed. Soil water content was measured to 300cm depth throughout the growing season. Significant water extraction occurred to a depth of 240–300cm and seasonal water use was calculated from the change in soil water over this rooting zone. Grain yield increased significantly with year of commercialization, but no such trend was observed for total water extraction. Therefore, the measured genetic gain for yield for the period represented by this set of hybrids must be related to either increased efficiency of water use or increased carbon partitioning to the grain, rather than increased soil water uptake. PMID:26428065

  9. Genetic data from algae sedimentary DNA reflect the influence of environment over geography

    PubMed Central

    Stoof-Leichsenring, Kathleen R.; Herzschuh, Ulrike; Pestryakova, Luidmila A.; Klemm, Juliane; Epp, Laura S.; Tiedemann, Ralph

    2015-01-01

    Genetic investigations on eukaryotic plankton confirmed the existence of modern biogeographic patterns, but analyses of palaeoecological data exploring the temporal variability of these patterns have rarely been presented. Ancient sedimentary DNA proved suitable for investigations of past assemblage turnover in the course of environmental change, but genetic relatedness of the identified lineages has not yet been undertaken. Here, we investigate the relatedness of diatom lineages in Siberian lakes along environmental gradients (i.e. across treeline transects), over geographic distance and through time (i.e. the last 7000 years) using modern and ancient sedimentary DNA. Our results indicate that closely-related Staurosira lineages occur in similar environments and less-related lineages in dissimilar environments, in our case different vegetation and co-varying climatic and limnic variables across treeline transects. Thus our study reveals that environmental conditions rather than geographic distance is reflected by diatom-relatedness patterns in space and time. We tentatively speculate that the detected relatedness pattern in Staurosira across the treeline could be a result of adaptation to diverse environmental conditions across the arctic boreal treeline, however, a geographically-driven divergence and subsequent repopulation of ecologically different habitats might also be a potential explanation for the observed pattern. PMID:26261899

  10. Genetic data from algae sedimentary DNA reflect the influence of environment over geography

    NASA Astrophysics Data System (ADS)

    Stoof-Leichsenring, Kathleen R.; Herzschuh, Ulrike; Pestryakova, Luidmila A.; Klemm, Juliane; Epp, Laura S.; Tiedemann, Ralph

    2015-08-01

    Genetic investigations on eukaryotic plankton confirmed the existence of modern biogeographic patterns, but analyses of palaeoecological data exploring the temporal variability of these patterns have rarely been presented. Ancient sedimentary DNA proved suitable for investigations of past assemblage turnover in the course of environmental change, but genetic relatedness of the identified lineages has not yet been undertaken. Here, we investigate the relatedness of diatom lineages in Siberian lakes along environmental gradients (i.e. across treeline transects), over geographic distance and through time (i.e. the last 7000 years) using modern and ancient sedimentary DNA. Our results indicate that closely-related Staurosira lineages occur in similar environments and less-related lineages in dissimilar environments, in our case different vegetation and co-varying climatic and limnic variables across treeline transects. Thus our study reveals that environmental conditions rather than geographic distance is reflected by diatom-relatedness patterns in space and time. We tentatively speculate that the detected relatedness pattern in Staurosira across the treeline could be a result of adaptation to diverse environmental conditions across the arctic boreal treeline, however, a geographically-driven divergence and subsequent repopulation of ecologically different habitats might also be a potential explanation for the observed pattern.

  11. Knowledge, attitudes and preferences regarding genetic testing for smoking cessation. A cross-sectional survey among Dutch smokers.

    PubMed

    Quaak, Marieke; Smerecnik, Chris; van Schooten, Frederik J; de Vries, Hein; van Schayck, Constant P

    2012-01-01

    Objectives Recent research strongly suggests that genetic variation influences smokers' ability to stop. Therefore, the use of (pharmaco) genetic testing may increase cessation rates. This study aims to assess the intention of smokers concerning undergoing genetic testing for smoking cessation and their knowledge, attitudes and preferences about this subject. Design Online cross-sectional survey. Setting Database internet research company of which every inhabitant of the Netherlands of ≥12 years with an email address and capable of understanding Dutch can become a member. Participants 587 of 711 Dutch smokers aged ≥18 years, daily smokers for ≥5 years and smoke on average ≥10 cigarettes/day (response rate=83%). Primary and secondary outcome measures Smokers' knowledge, attitudes and preferences and their intention to undergo genetic testing for smoking cessation. Results Knowledge on the influence of genetic factors in smoking addiction and cessation was found to be low. Smokers underestimated their chances of having a genetic predisposition and the influence of this on smoking cessation. Participants perceived few disadvantages, some advantages and showed moderate self-efficacy towards undergoing a genetic test and dealing with the results. Smokers were mildly interested in receiving information and participating in genetic testing, especially when offered by their general practitioner (GP). Conclusions For successful implementation of genetic testing for smoking in general practice, several issues should be addressed, such as the knowledge on smoking cessation, genetics and genetic testing (including advantages and disadvantages) and the influence of genetics on smoking addiction and cessation. Furthermore, smokers allocate their GPs a crucial role in the provision of information and the delivery of a genetic test for smoking; however, it is unclear whether GPs will be able and willing to take on this role. PMID:22223839

  12. The Effect of Preimplantation Genetic Screening on Implantation Rate in Women over 35 Years of Age

    PubMed Central

    Moayeri, Mina; Saeidi, Hojatolah; Modarresi, Mohammad Hossein; Hashemi, Mehrdad

    2016-01-01

    Objective Advanced maternal age (AMA) is an important factor in decreasing success of assisted reproductive technology by having a negative effect on the success rate of intra-cytoplasmic sperm injection (ICSI), particularly by increasing the rate of embryo aneuploidy. It has been suggested that the transfer of euploid embryos increases the implantation and pregnancy rates, and decreases the abortion rate. Preimplantation genetic screening (PGS) is a method for selection of euploid embryos. Past studies, however, have reported different results on the success of pregnancy after PGS in AMA. Investigating the pregnancy rate of ICSI with and without PGS in female partners over 35 years of age referred to infertility centers in Tehran. Materials and Methods In this randomized controlled trial, 150 couples with the female partner over age of 35 were included. Fifty couples underwent PGS and the remaining were used as the control group. PGS was carried out using fluorescent in situ hybridization (FISH) for chromosomes 13, 18, 21, X and Y. Results of embryo transfer following PGS were evaluated and compared with those in the control group. Results Implantation rates obtained in the PGS and control groups were 30 and 32% respectively and not significantly different (P>0.05). Conclusion PGS for chromosomes 13, 18, 21, X and Y does not increase implantation rate in women over 35 years of age and therefore the regular use of PGS in AMA is not recommended. PMID:27054114

  13. Genetic stability of vaccine strain Salmonella Typhi Ty21a over 25 years.

    PubMed

    Kopecko, Dennis J; Sieber, Heike; Ures, Jose A; Fürer, Andreas; Schlup, Jacqueline; Knof, Ulrich; Collioud, Andre; Xu, Deqi; Colburn, Kevin; Dietrich, Guido

    2009-04-01

    The attenuated live bacterial vaccine strain Salmonella enterica Serovar Typhi Ty21a is the main constituent of Vivotif, the only licensed oral vaccine against typhoid fever. The strain was developed in the 1970s by chemical mutagenesis. In the course of this mutagenesis, a number of mutations were introduced into the vaccine strain. Characterisation of the vaccine strain during development as well as release of master- and working seed lots (MSL and WSL) and commercial batches is based on phenotypic assays assessing microbiological and biochemical characteristics of Ty21a. In the current study, we have analysed by DNA sequencing the specific mutations originally correlated with the attenuation of strain Ty21a. These data demonstrate the stability of these mutations for MSLs and WSLs of Ty21a produced between 1980 and 2005. Finally, we have confirmed the correlation of these genetic mutations with the expected phenotypic attenuations for the seed lots used in vaccine manufacture over 25 years. PMID:19121604

  14. Parametric representation of open quantum systems and cross-over from quantum to classical environment.

    PubMed

    Calvani, Dario; Cuccoli, Alessandro; Gidopoulos, Nikitas I; Verrucchi, Paola

    2013-04-23

    The behavior of most physical systems is affected by their natural surroundings. A quantum system with an environment is referred to as open, and its study varies according to the classical or quantum description adopted for the environment. We propose an approach to open quantum systems that allows us to follow the cross-over from quantum to classical environments; to achieve this, we devise an exact parametric representation of the principal system, based on generalized coherent states for the environment. The method is applied to the s = 1/2 Heisenberg star with frustration, where the quantum character of the environment varies with the couplings entering the Hamiltonian H. We find that when the star is in an eigenstate of H, the central spin behaves as if it were in an effective magnetic field, pointing in the direction set by the environmental coherent-state angle variables (θ, ϕ), and broadened according to their quantum probability distribution. Such distribution is independent of ϕ, whereas as a function of θ is seen to get narrower as the quantum character of the environment is reduced, collapsing into a Dirac-δ function in the classical limit. In such limit, because ϕ is left undetermined, the Von Neumann entropy of the central spin remains finite; in fact, it is equal to the entanglement of the original fully quantum model, a result that establishes a relation between this latter quantity and the Berry phase characterizing the dynamics of the central spin in the effective magnetic field. PMID:23572581

  15. Cross-over study of the efficacy of four beta 2-sympathomimetic bronchodilator aerosols.

    PubMed Central

    Madsen, B W; Tandon, M K; Paterson, J W

    1979-01-01

    1 Bronchodilator efficacy of four beta 2-sympathomimetic aerosols, fenoterol, orciprenaline, salbutamol and terbutaline has been compared in nine patients with chronic stable reversible airways obstruction using a double-blind placebo controlled cross-over design. Two puffs of each agent were given on two separate occasions to each of the patients and the forced expiratory volume in one second (FEV1) and the vital capacity (VC) were measured before and 30, 90, 150 and 210 min after administration. 2 Multivariate analysis of the data at 30 min showed FEV1 and VC in these patients to be so highly correlated that they could be considered as a single variable. 3 When absolute change in VC at 30 min was used as the response criterion, efficacy of the four drugs was significantly better than placebo (P < 0.01). It was not possible to rank all four drugs in order of effectiveness; fenoterol and salbutamol were significantly better than terbutaline and orciprenaline (P < 0.01) but this was complicated by a significant interaction effect between drugs and patients (P < 0.01). 4 Similar results were obtained when absolute and relative changes in FEV1 and VC and area under the curve were used as response variables. 5 The study demonstrates that important individual differences in patient response may be concealed if only average drug effects are considered. PMID:45195

  16. Oral Solubilized Ursodeoxycholic Acid Therapy in Amyotrophic Lateral Sclerosis: A Randomized Cross-Over Trial

    PubMed Central

    Min, Ju-Hong; Hong, Yoon-Ho; Sung, Jung-Joon; Kim, Sung-Min; Lee, Jung Bok

    2012-01-01

    To evaluate the efficacy and safety of ursodeoxycholic acid (UDCA) with oral solubilized formula in amyotrophic lateral sclerosis (ALS) patients, patients with probable or definite ALS were randomized to receive oral solubilized UDCA (3.5 g/140 mL/day) or placebo for 3 months after a run-in period of 1 month and switched to receive the other treatment for 3 months after a wash-out period of 1 month. The primary outcome was the rate of progression, assessed by the Appel ALS rating scale (AALSRS), and the secondary outcomes were the revised ALS functional rating scale (ALSFRS-R) and forced vital capacity (FVC). Fifty-three patients completed either the first or second period of study with only 16 of 63 enrolled patients given both treatments sequentially. The slope of AALSRS was 1.17 points/month lower while the patients were treated with UDCA than with placebo (95% CI for difference 0.08-2.26, P = 0.037), whereas the slopes of ALSFRS-R and FVC did not show significant differences between treatments. Gastrointestinal adverse events were more common with UDCA (P < 0.05). Oral solubilized UDCA seems to be tolerable in ALS patients, but we could not make firm conclusion regarding its efficacy, particularly due to the high attrition rate in this cross-over trial. PMID:22323869

  17. Cross-over of hydrophobic effects observed in amphiphilic aqueous solutions

    NASA Astrophysics Data System (ADS)

    Huang, Ningdong; Nordlund, Dennis; Huang, Congcong; Tyliszczak, Tolek; Acremann, Yves; Nilsson, Anders

    2010-03-01

    The hydrophobic effect is important in nature and responsible for phenomena in many fields. Changes in structure and dynamics of water induced by apolar groups are believed to play a key role in protein folding, ligand binding and formation of biological membranes. The length scale dependence of hydrophobic and associated crossover length has been discussed intensively, but has not been observed directly by experimental techniques sensitive to the microscopic structure. Here we report experimental evidences for the cross over behavior of hydrophobic effects in amphiphilic aqueous solutions based on x-ray adsorption and small angle x-ray scattering data. Tetraalkyl ammonium (CnH2n+1)4N^+ (TAA) cations show hydrophobic effects on the structure of water other than ionic effects. For cations with shorter side hydrocarbon chains, hydrophobic hydration enhances the hydrogen bonds (HBs) in liquid water and separates the solute with solvents; whereas for cations with longer chains (˜ 5 A) we find that the HBs are weakened and the solutes and solvent are attracted to each other. The temperature dependence of the crossover length is also investigated.

  18. First principles study of thermal conductivity cross-over in nanostructured zinc-chalcogenides

    SciTech Connect

    Katre, Ankita; Madsen, Georg K. H.; Togo, Atsushi; Tanaka, Isao

    2015-01-28

    Systematic first principles studies of zinc-chalcogenides have been performed to understand their thermal transport behaviour. We have applied the Boltzmann transport equation in the relaxation time approximation to calculate the thermal conductivity of ZnS, ZnSe, and ZnTe. We find a thermal conductivity cross-over between ZnS and ZnSe at nanostructure sizes around 0.1–0.2 μm and explain this in terms of the different contributions of phonon modes in these materials. We study the effect of nanostructuring using both the diffusive boundary scattering and confined mean free path limit and discuss the variations in the results. Furthermore, we show the strong influence of isotope scattering on the thermal conductivity. The calculated thermal conductivity is found to be strongly dependent on the volume and we explain the observed differences between local density and generalized gradient approximation calculations. We compare further calculated thermal properties, such as the thermal expansion coefficient, to experiment to validate our approach.

  19. Cross-layer optimization for video transmission over multirate GMC-CDMA wireless links.

    PubMed

    Bandyopadhyay, Saurav K; Partasides, George; Kondi, Lisimachos P

    2008-06-01

    In this paper, we consider the problem of video transmission over wireless generalized multicarrier code division multiple access (GMC-CDMA) systems. Such systems offer deterministic elimination of multiple access interference. A scalable video source codec is used and a multirate setup is assumed, i.e., each video user is allowed to occupy more than one GMC-CDMA channels. Furthermore, each of these channels can utilize a different number of subcarriers. We propose a cross-layer optimization method to select the source coding rate, channel coding rate, number of subcarriers per GMC-CDMA channel and transmission power per GMC-CDMA channel given a maximum transmission power for each video user and an available chip rate. Universal rate distortion characteristics (URDC) are used to approximate the expected distortion at the receiver. The proposed algorithm is optimal in the operational rate distortion sense, subject to the specific setup used and the approximation caused by the use of the URDC. Experimental results are presented and conclusions are drawn. PMID:18482895

  20. Ultrasensitive detection of genetically modified plants by fluorescence cross-correlation spectroscopy

    NASA Astrophysics Data System (ADS)

    Li, Junfeng; Xing, Da; Chen, Tongsheng; Liu, Jinfeng

    2006-09-01

    In this study, a novel method for the direct detection of GMP without amplified by the general method of PCR is firstly presented and proved by experiments. In our method, fluorescence correlation spectroscopy, cleaving nucleic acid by restriction endonuclease and two nucleic acid probe hybridization techniques are combined to distinguish the caulifiower mosaic virus (CaMV) 35S promoter and determine whether samples contain genetically modified components. The detection principle is as follows: firstly two restriction endonucleases FOKI and BsrDlare used to cleave the genomic DNA and the 169bp fragments of CaMV 35S promoter are retrieved; secondly, two nucleic acid probes labeled by Rhodamine Green and y5 dyes respectively hybridize with cleaved 169bp fragments of CaMV 35S promoter; thirdly, the hybridization products simultaneously with two dye-labeled probes are detected by fluorescence cross-correlation spectroscopy and GMP is distinguished. As the detection and analysis by FCS can be performed at the level of single molecule, there is no need for any type of amplification. Genetically modified tobaccos are measured by this method. The results indicate this method can detect CaMV 35S promoter of GMP exactly and the sensitivity can be down to 3.47X10 -10M. Because no any type of amplification is involved, this method can avoid the non-specffic amplification and false-positive problems of PCR, Due to its high-sensitivity, simplicity, reliability and little need for sample amounts, this method promises to be a highly effective detection method for GMP.

  1. Genetic and experimental evidence for cross-species infection by swine hepatitis E virus.

    PubMed

    Meng, X J; Halbur, P G; Shapiro, M S; Govindarajan, S; Bruna, J D; Mushahwar, I K; Purcell, R H; Emerson, S U

    1998-12-01

    Prior to the recent discovery of the swine hepatitis E virus (swine HEV) in pigs from the midwestern United States, HEV was not considered endemic to this country. Since swine HEV is antigenically and genetically related to human strains of HEV, it was important to characterize this new virus further. The infectivity titer of a pool of swine HEV in pigs was determined in order to prepare a standardized reagent and to evaluate the dose response in pigs. Although the sequence of swine HEV varied extensively from those of most human strains of HEV, it was very closely related to the two strains of human HEV (US-1 and US-2) isolated in the United States. The U.S. strains which were recently recovered from two patients with clinical hepatitis E in the United States shared >/=97% amino acid identity with swine HEV in open reading frames 1 and 2. Phylogenetic analyses of different regions of the genome revealed that swine HEV and the U.S. strains grouped together and formed a distinct branch. These results suggested that swine HEV may infect humans. When we inoculated rhesus monkeys and a chimpanzee, experimental surrogates of humans, with swine HEV, the primates became infected. Furthermore, in a reciprocal experiment, specific-pathogen-free pigs were experimentally infected with the US-2 strain of human HEV that is genetically similar to swine HEV. These results provided experimental evidence for cross-species infection by the swine virus. Thus, humans appear to be at risk of infection with swine HEV or closely related viruses. PMID:9811705

  2. First measurement of the tt[over ] differential cross section dsigma/dM_{tt[over ]} in pp[over ] collisions at sqrt[s]=1.96 TeV.

    PubMed

    Aaltonen, T; Adelman, J; Akimoto, T; Alvarez González, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Apresyan, A; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Azzurri, P; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Bartsch, V; Bauer, G; Beauchemin, P-H; Bedeschi, F; Beecher, D; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Beringer, J; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Bridgeman, A; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burke, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Calancha, C; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Chwalek, T; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Compostella, G; Convery, M E; Conway, J; Cordelli, M; Cortiana, G; Cox, C A; Cox, D J; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; Dagenhart, D; Datta, M; Davies, T; de Barbaro, P; De Cecco, S; Deisher, A; De Lorenzo, G; Dell'orso, M; Deluca, C; Demortier, L; Deng, J; Deninno, M; Derwent, P F; di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Elagin, A; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Ferrazza, C; Field, R; Flanagan, G; Forrest, R; Frank, M J; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garberson, F; Garcia, J E; Garfinkel, A F; Genser, K; Gerberich, H; Gerdes, D; Gessler, A; Giagu, S; Giakoumopoulou, V; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C M; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Han, B-Y; Han, J Y; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hays, C; Heck, M; Heijboer, A; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hewamanage, S; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Hussein, M; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jha, M K; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Kar, D; Karchin, P E; Kato, Y; Kephart, R; Keung, J; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, H W; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kreps, M; Kroll, J; Krop, D; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhr, T; Kulkarni, N P; Kurata, M; Kwang, S; Laasanen, A T; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; Lecompte, T; Lee, E; Lee, H S; Lee, S W; Leone, S; Lewis, J D; Lin, C-S; Linacre, J; Lindgren, M; Lipeles, E; Liss, T M; Lister, A; Litvintsev, D O; Liu, C; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lovas, L; Lucchesi, D; Luci, C; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Macqueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis-Katsikakis, A; Margaroli, F; Marino, C; Marino, C P; Martin, A; Martin, V; Martínez, M; Martínez-Ballarín, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Mathis, M; Mattson, M E; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzione, A; Merkel, P; Mesropian, C; Miao, T; Miladinovic, N; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyake, H; Moggi, N; Moon, C S; Moore, R; Morello, M J; Morlock, J; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Nett, J; Neu, C; Neubauer, M S; Neubauer, S; Nielsen, J; Nodulman, L; Norman, M; Norniella, O; Nurse, E; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Osterberg, K; Pagan Griso, S; Palencia, E; Papadimitriou, V; Papaikonomou, A; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Peiffer, T; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Pianori, E; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Pueschel, E; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Renton, P; Renz, M; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rodriguez, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Roy, P; Ruiz, A; Russ, J; Rusu, V; Rutherford, B; Saarikko, H; Safonov, A; Sakumoto, W K; Saltó, O; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savoy-Navarro, A; Schlabach, P; Schmidt, A; Schmidt, E E; Schmidt, M A; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sforza, F; Sfyrla, A; Shalhout, S Z; Shears, T; Shepard, P F; Shimojima, M; Shiraishi, S; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakyan, A; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spreitzer, T; Squillacioti, P; Stanitzki, M; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Strycker, G L; Stuart, D; Suh, J S; Sukhanov, A; Suslov, I; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Thom, J; Thompson, A S; Thompson, G A; Thomson, E; Tipton, P; Ttito-Guzmán, P; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Tourneur, S; Trovato, M; Tsai, S-Y; Tu, Y; Turini, N; Ukegawa, F; Vallecorsa, S; van Remortel, N; Varganov, A; Vataga, E; Vázquez, F; Velev, G; Vellidis, C; Vidal, M; Vidal, R; Vila, I; Vilar, R; Vine, T; Vogel, M; Volobouev, I; Volpi, G; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wagner-Kuhr, J; Wakisaka, T; Wallny, R; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Weinelt, J; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Wilbur, S; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Würthwein, F; Xie, S; Yagil, A; Yamamoto, K; Yamaoka, J; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zhang, X; Zheng, Y; Zucchelli, S

    2009-06-01

    We present a measurement of the tt[over ] differential cross section with respect to the tt[over ] invariant mass, dsigma/dM_{tt[over ]}, in pp[over ] collisions at sqrt[s]=1.96 TeV using an integrated luminosity of 2.7 fb;{-1} collected by the CDF II experiment. The tt[over ] invariant mass spectrum is sensitive to a variety of exotic particles decaying into tt[over ] pairs. The result is consistent with the standard model expectation, as modeled by PYTHIA with CTEQ5L parton distribution functions. PMID:19658857

  3. Analysis of spatial genetic structure in an expanding Pinus halepensis population reveals development of fine-scale genetic clustering over time.

    PubMed

    Troupin, D; Nathan, R; Vendramin, G G

    2006-10-01

    We analysed the change of spatial genetic structure (SGS) of reproductive individuals over time in an expanding Pinus halepensis population. To our knowledge, this is the first empirical study to analyse the temporal component of SGS by following the dynamics of successive cohorts of the same population over time, rather than analysing different age cohorts at a single time. SGS is influenced by various factors including restricted gene dispersal, microenvironmental selection, mating patterns and the spatial pattern of reproductive individuals. Several factors that affect SGS are expected to vary over time and as adult density increases. Using air photo analysis, tree-ring dating and molecular marker analysis we reconstructed the spread of reproductive individuals over 30 years beginning from five initial individuals. In the early stages, genotypes were distributed randomly in space. Over time and with increasing density, fine-scale (< 20 m) SGS developed and the magnitude of genetic clustering increased. The SGS was strongly affected by the initial spatial distribution and genetic variation of the founding individuals. The development of SGS may be explained by fine-scale environmental heterogeneity and possibly microenvironmental selection. Inbreeding and variation in reproductive success may have enhanced SGS magnitude over time. PMID:17032261

  4. Cross-Spectra Over the Sea from Observations and Mesoscale Modelling

    NASA Astrophysics Data System (ADS)

    Vincent, C. L.; Larsén, X. G.; Larsen, S. E.; Sørensen, P.

    2013-02-01

    Cospectra and quadrature spectra are calculated for six pairs of tall offshore measurement masts near the Horns Rev I wind farm in the Danish North Sea and the Nysted wind farm in the Baltic sea. The mast-pairs are separated from one another by horizontal distances of 2.13-12.4 km. Cospectra and quadrature spectra for the two sites are classified in terms of the angle between the mean wind direction and the line connecting each pair of masts. The frequency axes of the spectra are normalized to remove the effect of mean wind speed and separation distance. Results indicate a larger contribution to the quadrature spectrum for flow from the sea than for flow from the land, and the patterns in the spectra are clearer and better defined for Horns Rev I (which has a long uninterrupted sea-fetch from the west) than for Nysted (which is surrounded by a more complicated coastline). The analysis is replicated based on 3-month simulations using the weather research and forecasting (WRF) numerical model with a horizontal grid spacing of 2 km. For the sea-fetch directions, good agreement in spectral properties between the model and observations is found. Analytical expressions based on the properties of the cross-correlation function and an exponentially decaying coherence function are fitted to the normalized cospectra and quadrature spectra. The expressions are shown to be a good fit to the spectra calculated from the WRF simulations and to the observed spectra for directions with a long sea-fetch, which suggests that to a good approximation, the average cospectra and quadrature spectra over the sea can be written as functions of frequency, mean wind speed, separation distance and the angle between the wind direction and the orientation of the masts.

  5. CRY1 and CRY2 genetic variants in seasonality: A longitudinal and cross-sectional study.

    PubMed

    Kovanen, Leena; Donner, Kati; Kaunisto, Mari; Partonen, Timo

    2016-08-30

    Cryptochromes are key components of the circadian clocks that generate and maintain seasonal variations. The aim of our study was to analyze the associations of CRY1 and CRY2 genetic variants with the problematicity of seasonal variations, and whether the problematicity of seasonal variations changed during the follow-up of 11 years. Altogether 21 CRY1 and 16 CRY2 single-nucleotide polymorphisms (SNPs) were genotyped and analyzed in 5910 individuals from a Finnish nationwide population-based sample who had filled in the self-report on the seasonal variations in mood and behavior in the year 2000. In the year 2011, 3356 of these individuals filled in the same self-report on the seasonal variations in mood and behavior. Regression models were used to test whether any of the SNPs associated with the problematicity of seasonal variations or with a change in the problematicity from 2000 to 2011. In the longitudinal analysis, CRY2 SNP rs61884508 was protective from worsening of problematicity of seasonal variations. In the cross-sectional analysis, CRY2 SNP rs72902437 showed evidence of association with problematicity of seasonal variations, as did SNP rs1554338 (in the MAPK8IP1 and downstream of CRY2). PMID:27267441

  6. The actinin family of actin cross-linking proteins - a genetic perspective.

    PubMed

    Murphy, Anita C H; Young, Paul W

    2015-01-01

    Actinins are one of the major actin cross-linking proteins found in virtually all cell types and are the ancestral proteins of a larger family that includes spectrin, dystrophin and utrophin. Invertebrates have a single actinin-encoding ACTN gene, while mammals have four. Mutations in all four human genes have now been linked to heritable diseases or traits. ACTN1 mutations cause macrothrombocytopenia, a platelet disorder characterized by excessive bleeding. ACTN2 mutations have been linked to a range of cardiomyopathies, and ACTN4 mutations cause a kidney condition called focal segmental glomerulosclerosis. Intriguingly, approximately 16 % of people worldwide are homozygous for a nonsense mutation in ACTN3 that abolishes actinin-3 protein expression. This ACTN3 null allele has undergone recent positive selection in specific human populations, which may be linked to improved endurance and adaptation to colder climates. In this review we discuss the human genetics of the ACTN gene family, as well as ACTN gene knockout studies in several model organisms. Observations from both of these areas provide insights into the evolution and cellular functions of actinins. PMID:26312134

  7. The cell pole: the site of cross talk between the DNA uptake and genetic recombination machinery.

    PubMed

    Kidane, Dawit; Ayora, Silvia; Sweasy, Joann B; Graumann, Peter L; Alonso, Juan C

    2012-01-01

    Natural transformation is a programmed mechanism characterized by binding of free double-stranded (ds) DNA from the environment to the cell pole in rod-shaped bacteria. In Bacillus subtilis some competence proteins, which process the dsDNA and translocate single-stranded (ss) DNA into the cytosol, recruit a set of recombination proteins mainly to one of the cell poles. A subset of single-stranded binding proteins, working as "guardians", protects ssDNA from degradation and limit the RecA recombinase loading. Then, the "mediators" overcome the inhibitory role of guardians, and recruit RecA onto ssDNA. A RecA·ssDNA filament searches for homology on the chromosome and, in a process that is controlled by "modulators", catalyzes strand invasion with the generation of a displacement loop (D-loop). A D-loop resolvase or "resolver" cleaves this intermediate, limited DNA replication restores missing information and a DNA ligase seals the DNA ends. However, if any step fails, the "rescuers" will repair the broken end to rescue chromosomal transformation. If the ssDNA does not share homology with resident DNA, but it contains information for autonomous replication, guardian and mediator proteins catalyze plasmid establishment after inhibition of RecA. DNA replication and ligation reconstitute the molecule (plasmid transformation). In this review, the interacting network that leads to a cross talk between proteins of the uptake and genetic recombination machinery will be placed into prospective. PMID:23046409

  8. Interpopulation crosses, inheritance study, and genetic variability in the brown planthopper complex, Nilaparvata lugens (Homoptera: Delphacidae).

    PubMed

    Latif, M A; Omar, Mohd Yosuh; Tan, Soon Guan; Siraj, Siti Shapor; Ismail, Abdul Rahim

    2010-04-01

    Studies on hybridization, inheritance, and population genetics of brown planthoppers that infest rice and weeds were undertaken using starch gel electrophoresis to determine whether the weed-infesting population represents a biological race or a species. F(1) and F(2) generations were produced by crosses between parental insects from the two populations with little indication of hybrid sterility. Gpi, Mdh, and Idh loci were inherited in a simple Mendelian fashion in families of two sympatric populations. Sixteen populations of Nilaparvata spp. from eight locations were collected. The Mdh, Idh, Pgm, Gpi, 6Pgd, and Acp loci were polymorphic. The N. lugens of rice with high esterase activity were clustered into a group and characterized by the presence of alleles Gpi (110) and Gpi (120), whereas N. lugens from weeds with low esterase activity were clustered into another group and characterized by Gpi (100) and Gpi (90) . There was a lack of heterozygotes between the common alleles of the two populations. This means that the two groups of individuals belong to different gene pools. PMID:19967400

  9. Relationships between parental negativity and childhood antisocial behavior over time: a bidirectional effects model in a longitudinal genetically informative design.

    PubMed

    Larsson, Henrik; Viding, Essi; Rijsdijk, Fruhling V; Plomin, Robert

    2008-07-01

    This study examined the direction and etiology underlying the relationships between parental negativity and early childhood antisocial behavior using a bidirectional effects model in a longitudinal genetically informative design. We analyzed parent reports of parental negativity and early childhood antisocial behavior in 6,230 pairs of twins at 4 and 7 years of age. Results from a cross-lagged twin model contribute to the understanding of the mechanisms underlying the bidirectional processes involved in parental negativity and childhood antisocial behavior. Specifically, the findings of this study suggest that the association between parenting and child antisocial behavior is best explained by both parent-driven and child-driven effects. We found support for the notion that parent's negative feelings towards their children environmentally mediate the risk for child antisocial behavior. We also found evidence of genetically mediated child effects; in which genetically influenced antisocial behavior evoke parental negativity towards the child. PMID:17602294

  10. Closed-loop separation control over a sharp edge ramp using genetic programming

    NASA Astrophysics Data System (ADS)

    Debien, Antoine; von Krbek, Kai A. F. F.; Mazellier, Nicolas; Duriez, Thomas; Cordier, Laurent; Noack, Bernd R.; Abel, Markus W.; Kourta, Azeddine

    2016-03-01

    We experimentally perform open and closed-loop control of a separating turbulent boundary layer downstream from a sharp edge ramp. The turbulent boundary layer just above the separation point has a Reynolds number Re_{θ }≈ 3500 based on momentum thickness. The goal of the control is to mitigate separation and early re-attachment. The forcing employs a spanwise array of active vortex generators. The flow state is monitored with skin-friction sensors downstream of the actuators. The feedback control law is obtained using model-free genetic programming control (GPC) (Gautier et al. in J Fluid Mech 770:442-457, 2015). The resulting flow is assessed using the momentum coefficient, pressure distribution and skin friction over the ramp and stereo PIV. The PIV yields vector field statistics, e.g. shear layer growth, the back-flow area and vortex region. GPC is benchmarked against the best periodic forcing. While open-loop control achieves separation reduction by locking-on the shedding mode, GPC gives rise to similar benefits by accelerating the shear layer growth. Moreover, GPC uses less actuation energy.

  11. Lifespan and lesions in genetically heterogeneous (four-way cross) mice: a new model for aging research.

    PubMed

    Chrisp, C E; Turke, P; Luciano, A; Swalwell, S; Peterson, J; Miller, R A

    1996-11-01

    Genetically heterogeneous animal models provide many advantages for research on aging but have been used infrequently. We present here lifespan and lesion data from a study of mice bred as a cross between (AKR/J x DBA/2J)F1 females and (C57BL/6J x SJL/J)F1 males. In such a four-way cross population, each mouse is genetically unique, but replicate populations of essentially similar genetic structure can be generated quickly, at low cost, and of arbitrary size from commercially available, genetically stable hybrid parents. We employed a protocol in which mice judged to be severely ill were euthanatized to obtain tissue in optimal condition for necropsy, and we were able to infer a likely cause of illness in 42 of 44 animals. Malignant lymphoma, including at least four histopathologically distinct subtypes, was the most common cause and was also a frequent incidental finding in mice dying of other causes. Neoplastic disease, benign or malignant, was the sole or a contributing cause of illness in 90% of the mice for which a cause could plausibly be assigned. A wide range of lethal and nonlethal degenerative lesions was also noted. The coefficient of variation for lifespan in these genetically heterogeneous mice was 26%, similar to that seen in analyses of recombinant inbred mouse lines. Baseline lifespan and pathology data on four-way cross mice is a useful prelude to the exploitation of this rodent model in tests of genetic and mechanistic hypotheses about aging. PMID:8952040

  12. Population dynamics of a natural red deer population over 200 years detected via substantial changes of genetic variation.

    PubMed

    Hoffmann, Gunther Sebastian; Johannesen, Jes; Griebeler, Eva Maria

    2016-05-01

    Most large mammals have constantly been exposed to anthropogenic influence over decades or even centuries. Because of their long generation times and lack of sampling material, inferences of past population genetic dynamics, including anthropogenic impacts, have only relied on the analysis of the structure of extant populations. Here, we investigate for the first time the change in the genetic constitution of a natural red deer population over two centuries, using up to 200-year-old antlers (30 generations) stored in trophy collections. To the best of our knowledge, this is the oldest DNA source ever used for microsatellite population genetic analyses. We demonstrate that government policy and hunting laws may have strong impacts on populations that can lead to unexpectedly rapid changes in the genetic constitution of a large mammal population. A high ancestral individual polymorphism seen in an outbreeding population (1813-1861) was strongly reduced in descendants (1923-1940) during the mid-19th and early 20th century by genetic bottlenecks. Today (2011), individual polymorphism and variance among individuals is increasing in a constant-sized (managed) population. Differentiation was high among periods (F ST > ***); consequently, assignment tests assigned individuals to their own period with >85% probability. In contrast to the high variance observed at nuclear microsatellite loci, mtDNA (D-loop) was monomorphic through time, suggesting that male immigration dominates the genetic evolution in this population. PMID:27096075

  13. Estimating Typhoon Rainfall over Sea from SSM/I Satellite Data Using an Improved Genetic Programming

    NASA Astrophysics Data System (ADS)

    Yeh, K.; Wei, H.; Chen, L.; Liu, G.

    2010-12-01

    Estimating Typhoon Rainfall over Sea from SSM/I Satellite Data Using an Improved Genetic Programming Keh-Chia Yeha, Hsiao-Ping Weia,d, Li Chenb, and Gin-Rong Liuc a Department of Civil Engineering, National Chiao Tung University, Hsinchu, Taiwan, 300, R.O.C. b Department of Civil Engineering and Engineering Informatics, Chung Hua University, Hsinchu, Taiwan, 300, R.O.C. c Center for Space and Remote Sensing Research, National Central University, Tao-Yuan, Taiwan, 320, R.O.C. d National Science and Technology Center for Disaster Reduction, Taipei County, Taiwan, 231, R.O.C. Abstract This paper proposes an improved multi-run genetic programming (GP) and applies it to predict the rainfall using meteorological satellite data. GP is a well-known evolutionary programming and data mining method, used to automatically discover the complex relationships among nonlinear systems. The main advantage of GP is to optimize appropriate types of function and their associated coefficients simultaneously. This study makes an improvement to enhance escape ability from local optimums during the optimization procedure. The GP continuously runs several times by replacing the terminal nodes at the next run with the best solution at the current run. The current novel model improves GP, obtaining a highly nonlinear mathematical equation to estimate the rainfall. In the case study, this improved GP described above combining with SSM/I satellite data is employed to establish a suitable method for estimating rainfall at sea surface during typhoon periods. These estimated rainfalls are then verified with the data from four rainfall stations located at Peng-Jia-Yu, Don-Gji-Dao, Lan-Yu, and Green Island, which are four small islands around Taiwan. From the results, the improved GP can generate sophisticated and accurate nonlinear mathematical equation through two-run learning procedures which outperforms the traditional multiple linear regression, empirical equations and back-propagated network

  14. Genetics

    MedlinePlus

    Homozygous; Inheritance; Heterozygous; Inheritance patterns; Heredity and disease; Heritable; Genetic markers ... The chromosomes are made up of strands of genetic information called DNA. Each chromosome contains sections of ...

  15. Genetics

    MedlinePlus

    ... Inheritance; Heterozygous; Inheritance patterns; Heredity and disease; Heritable; Genetic markers ... The chromosomes are made up of strands of genetic information called DNA. Each chromosome contains sections of ...

  16. Divergent selection on, but no genetic conflict over, female and male timing and rate of reproduction in a human population

    PubMed Central

    Bolund, Elisabeth; Bouwhuis, Sandra; Pettay, Jenni E.; Lummaa, Virpi

    2013-01-01

    The sexes often have different phenotypic optima for important life-history traits, and because of a largely shared genome this can lead to a conflict over trait expression. In mammals, the obligate costs of reproduction are higher for females, making reproductive timing and rate especially liable to conflict between the sexes. While studies from wild vertebrates support such sexual conflict, it remains unexplored in humans. We used a pedigreed human population from preindustrial Finland to estimate sexual conflict over age at first and last reproduction, reproductive lifespan and reproductive rate. We found that the phenotypic selection gradients differed between the sexes. We next established significant heritabilities in both sexes for all traits. All traits, except reproductive rate, showed strongly positive intersexual genetic correlations and were strongly genetically correlated with fitness in both sexes. Moreover, the genetic correlations with fitness were almost identical in men and women. For reproductive rate, the intersexual correlation and the correlation with fitness were weaker but again similar between the sexes. Thus, in this population, an apparent sexual conflict at the phenotypic level did not reflect an underlying genetic conflict over the studied reproductive traits. These findings emphasize the need for incorporating genetic perspectives into studies of human life-history evolution. PMID:24107531

  17. Topical Nasal Anesthesia in Flexible Bronchoscopy – A Cross-Over Comparison between Two Devices

    PubMed Central

    Fuehner, Thomas; Fuge, Jan; Jungen, Meike; Buck, Anna; Suhling, Hendrik; Welte, Tobias; Gottlieb, Jens; Greer, Mark

    2016-01-01

    Introduction Topical airway anesthesia is known to improve tolerance and patient satisfaction during flexible bronchoscopy (FB). Lidocaine is commonly used, delivered as an atomized spray. The current study assesses safety and patient satisfaction for nasal anesthesia of a new atomization device during outpatient bronchoscopy in lung transplant recipients. Methods Using a prospective, non-blinded, cross-over design, patients enrolled between 01-10-2014 and 24-11-2014 received 2% lidocaine using the standard reusable nasal atomizer (CRNA). Those enrolled between 25-11-2014 and 30-01-2015, received a disposable intranasal mucosal atomization device (DIMAD). After each procedure, the treating physician, their assistant and the patient independently rated side-effects and satisfaction, basing their responses on visual analogue scales (VAS). At their next scheduled bronchoscopy during the study period, patients then received the alternative atomizer. Written consent was obtained prior to the first bronchoscopy, and the study approved by the institutional ethics committee. Results Of the 252 patients enrolled between 01-10-2014 and 30-01-2015, 80 (32%) received both atomizers. Physicians reported better efficacy (p = 0.001) and fewer side effects (p< = 0.001) for DIMAD in patients exposed to both procedures. Among patients with one visit, physicians and their assistants reported improved efficacy (p = 0.018, p = 0.002) and fewer side effects (p< = 0.001, p = 0.029) for the disposable atomizer, whereas patients reported no difference in efficacy or side effects (p = 0.72 and p = 0.20). No severe adverse events were noted. The cost of the reusable device was 4.08€ per procedure, compared to 3.70€ for the disposable device. Discussion Topical nasal anesthesia via a disposable intranasal mucosal atomization device (DIMAD) offers comparable safety and patient comfort, compared to conventional reusable nasal atomizers (CRNA) in lung transplant recipients. Procedural costs

  18. Regional Brain Shrinkage over Two Years: Individual Differences and Effects of Pro-Inflammatory Genetic Polymorphisms

    PubMed Central

    Persson, N.; Ghisletta, P.; Dahle, C.L.; Bender, A.R.; Yang, Y.; Yuan, P.; Daugherty, A.M.; Raz, N.

    2014-01-01

    We examined regional changes in brain volume in healthy adults (N = 167, age 19-79 years at baseline; N = 90 at follow-up) over approximately two years. With latent change score models, we evaluated mean change and individual differences in rates of change in 10 anatomically-defined and manually-traced regions of interest (ROIs): lateral prefrontal cortex (LPFC), orbital frontal cortex (OF), prefrontal white matter (PFw), hippocampus (HC), parahippocampal gyrus (PhG), caudate nucleus (Cd), putamen (Pt), insula (In), cerebellar hemispheres (CbH), and primary visual cortex (VC). Significant mean shrinkage was observed in the HC, CbH, In, OF, and the PhG, and individual differences in change were noted in all regions, except the OF. Pro-inflammatory genetic variants mediated shrinkage in PhG and CbH. Carriers of two T alleles of interleukin-1β (IL-1βC-511T, rs16944) and a T allele of methylenetetrahydrofolate reductase (MTHFRC677T, rs1801133) polymorphisms showed increased PhG shrinkage. No effects of a pro-inflammatory polymorphism for C-reactive protein (CRP-286C>A>T, rs3091244) or apolipoprotein (APOE) ε4 allele were noted. These results replicate the pattern of brain shrinkage observed in previous studies, with a notable exception of the LPFC thus casting doubt on the unique importance of prefrontal cortex in aging. Larger baseline volumes of CbH and In were associated with increased shrinkage, in conflict with the brain reserve hypothesis. Contrary to previous reports, we observed no significant linear effects of age and hypertension on regional brain shrinkage. Our findings warrant further investigation of the effects of neuroinflammation on structural brain change throughout the lifespan. PMID:25264227

  19. Genetic parameters for body weight, carcass chemical composition and yield in a broiler-layer cross developed for QTL mapping

    PubMed Central

    Nunes, Beatriz do Nascimento; Ramos, Salvador Boccaletti; Savegnago, Rodrigo Pelicioni; Ledur, Mônica Corrêa; Nones, Kátia; Klein, Claudete Hara; Munari, Danísio Prado

    2011-01-01

    The objective of this study was to estimate genetic and phenotypic correlations of body weight at 6 weeks of age (BW6), as well as final carcass yield, and moisture, protein, fat and ash contents, using data from 3,422 F2 chickens originated from reciprocal cross between a broiler and a layer line. Variance components were estimated by the REML method, using animal models for evaluating random additive genetic and fixed contemporary group (sex, hatch and genetic group) effects. The heritability estimates (h2) for BW6, carcass yield and percentage of carcass moisture were 0.31 ± 0.07, 0.20 ± 0.05 and 0.33 ± 0.07, respectively. The h2 for the percentages of protein, fat and ash on a dry matter basis were 0.48 ± 0.09, 0.55 ± 0.10 and 0.36 ± 0.08, respectively. BW6 had a positive genetic correlation with fat percentage in the carcass, but a negative one with protein and ash contents. Carcass yield, thus, appears to have only low genetic association with carcass composition traits. The genetic correlations observed between traits, measured on a dry matter basis, indicated that selection for carcass protein content may favor higher ash content and a lower percentage of carcass fat. PMID:21931515

  20. Genetic and Environmental Contributions to Weight, Height, and BMI from Birth to 19 Years of Age: An International Study of Over 12,000 Twin Pairs

    PubMed Central

    Dubois, Lise; Ohm Kyvik, Kirsten; Girard, Manon; Tatone-Tokuda, Fabiola; Pérusse, Daniel; Hjelmborg, Jacob; Skytthe, Axel; Rasmussen, Finn; Wright, Margaret J.; Lichtenstein, Paul; Martin, Nicholas G.

    2012-01-01

    Objective To examine the genetic and environmental influences on variances in weight, height, and BMI, from birth through 19 years of age, in boys and girls from three continents. Design and Settings Cross-sectional twin study. Data obtained from a total of 23 twin birth-cohorts from four countries: Canada, Sweden, Denmark, and Australia. Participants were Monozygotic (MZ) and dizygotic (DZ) (same- and opposite-sex) twin pairs with data available for both height and weight at a given age, from birth through 19 years of age. Approximately 24,036 children were included in the analyses. Results Heritability for body weight, height, and BMI was low at birth (between 6.4 and 8.7% for boys, and between 4.8 and 7.9% for girls) but increased over time, accounting for close to half or more of the variance in body weight and BMI after 5 months of age in both sexes. Common environmental influences on all body measures were high at birth (between 74.1–85.9% in all measures for boys, and between 74.2 and 87.3% in all measures for girls) and markedly reduced over time. For body height, the effect of the common environment remained significant for a longer period during early childhood (up through 12 years of age). Sex-limitation of genetic and shared environmental effects was observed. Conclusion Genetics appear to play an increasingly important role in explaining the variation in weight, height, and BMI from early childhood to late adolescence, particularly in boys. Common environmental factors exert their strongest and most independent influence specifically in pre-adolescent years and more significantly in girls. These findings emphasize the need to target family and social environmental interventions in early childhood years, especially for females. As gene-environment correlation and interaction is likely, it is also necessary to identify the genetic variants that may predispose individuals to obesity. PMID:22347368

  1. Associations between reading achievement and independent reading in early elementary school: A genetically-informative cross-lagged study

    PubMed Central

    Harlaar, Nicole; Deater-Deckard, Kirby; Thompson, Lee A.; DeThorne, Laura S.; Petrill, Stephen A.

    2013-01-01

    This study used a cross-lagged twin design to examine reading achievement and independent reading from 10 to 11 years (n = 436 twin pairs). Reading achievement at age 10 significantly predicted independent reading at age 11. The alternative path, from independent reading at age 10 to reading achievement at age 11, was not significant. Individual differences in reading achievement and independent reading at both ages were primarily due to genetic influences. Furthermore, individual differences in independent reading at age 11 partly reflected genetic influences on reading achievement at age 10. These findings suggest that genetic influences that contribute to individual differences in children’s reading abilities also influence the extent to which children actively seek out and create opportunities to read. PMID:22026450

  2. Genetic loci with parent-of-origin effects cause hybrid seed lethality in crosses between Mimulus species.

    PubMed

    Garner, Austin G; Kenney, Amanda M; Fishman, Lila; Sweigart, Andrea L

    2016-07-01

    In flowering plants, F1 hybrid seed lethality is a common outcome of crosses between closely related diploid species, but the genetic basis of this early-acting and potentially widespread form of postzygotic reproductive isolation is largely unknown. We intercrossed two closely related species of monkeyflower, Mimulus guttatus and Mimulus tilingii, to characterize the mechanisms and strength of postzygotic reproductive isolation. Then, using a reciprocal backcross design, we performed high-resolution genetic mapping to determine the genetic architecture of hybrid seed lethality and directly test for loci with parent-of-origin effects. We found that F1 hybrid seed lethality is an exceptionally strong isolating barrier between Mimulus species, with reciprocal crosses producing < 1% viable seeds. This form of postzygotic reproductive isolation appears to be highly polygenic, indicating that multiple incompatibility loci have accumulated rapidly between these closely related Mimulus species. It is also primarily caused by genetic loci with parent-of-origin effects, suggesting a possible role for imprinted genes in the evolution of Mimulus hybrid seed lethality. Our findings suggest that divergence in loci with parent-of-origin effects, which is probably driven by genomic coevolution within lineages, might be an important source of hybrid incompatibilities between flowering plant species. PMID:26924810

  3. Is all fair in biological warfare? The controversy over genetically engineered biological weapons.

    PubMed

    Appel, J M

    2009-07-01

    Advances in genetics may soon make possible the development of ethnic bioweapons that target specific ethnic or racial groups based upon genetic markers. While occasional published reports of such research generate public outrage, little has been written about the ethical distinction (if any) between the development of such weapons and ethnically neutral bioweapons. The purpose of this paper is to launch a debate on the subject of ethnic bioweapons before they become a scientific reality. PMID:19567692

  4. Wavelength reuse in a bidirectional radio-over-fiber link based on cross-gain and cross-polarization modulation in a semiconductor optical amplifier.

    PubMed

    Zhu, Beibei; Pan, Shilong; Zhu, Dan; Yao, Jianping

    2013-09-15

    Wavelength reuse in a bidirectional radio-over-fiber link is proposed and demonstrated based on the cross-gain modulation (XGM) and the cross-polarization modulation in a semiconductor optical amplifier (SOA). With a polarization beam splitter placed at the remote antenna unit, the polarization-modulated signal generated at the SOA is converted into noninverted and inverted intensity-modulated signals. The noninverted signal is used to cancel the inverted XGM-induced intensity-modulated signal to form a clean optical carrier for wavelength reuse in upstream signal transmission, while the inverted intensity-modulated signal is combined constructively to enhance the XGM-induced signal, providing robust downlink service. A bidirectional transmission of 5 GHz RF signal carrying a 50 MBaud 16 quadrature amplitude modulation baseband signal is experimentally implemented. The error vector magnitude degradation due to the fiber transmission for both the downlink and uplink signal is about 0.2%. PMID:24104797

  5. Black and white and read all over: the past, present and future of giant panda genetics.

    PubMed

    Wei, Fuwen; Hu, Yibo; Zhu, Lifeng; Bruford, Michael W; Zhan, Xiangjiang; Zhang, Lei

    2012-12-01

    Few species attract much more attention from the public and scientists than the giant panda (Ailuropoda melanoleuca), a popular, enigmatic but highly endangered species. The application of molecular genetics to its biology and conservation has facilitated surprising insights into the biology of giant pandas as well as the effectiveness of conservation efforts during the past decades. Here, we review the history of genetic advances in this species, from phylogeny, demographical history, genetic variation, population structure, noninvasive population census and adaptive evolution to reveal to what extent the current status of the giant panda is a reflection of its evolutionary legacy, as opposed to the influence of anthropogenic factors that have negatively impacted this species. In addition, we summarize the conservation implications of these genetic findings applied for the management of this high-profile species. Finally, on the basis of these advances and predictable future changes in genetic technology, we discuss future research directions that seem promising for giant panda biology and conservation. PMID:23130639

  6. Feasibility demonstration of booster cross-over system for 3 1/2 inch SRB/MLP frangible nut system

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Recent testing of the SRB/MLP Frangible Nut System (SOS Part Number 114850-9/Boosters P/N 114848-3) at NASA indicated a need to reduce the function time between boosters (2) within a single frangible nut. These boosters are initiated separately by electrical impulse(s). Coupling the output of each detonator with an explosive cross-over would reduce the function time between boosters (independent of electrical impulse) while providing additional redundancy to the system. The objectives of this program were to: provide an explosive cross-over between boosters, reduce function time between boosters to less than one (1) millisecond within a given nut, reduce cost of boosters, be compatible with the existing frangible nut system, and meet requirements of USBI Spec's (nut 10SPC-0030, booster 10SPC-0031).

  7. Response analysis of buried pipelines crossing fault due to overlying soil rupture

    NASA Astrophysics Data System (ADS)

    Zhao, Lei; Cui, Chengchen; Li, Xiaojun

    2010-02-01

    A 3-D soil-pipe nonlinear finite element model with contact element is suggested and the influences of the rupture mode, thickness and rigidity of overlying soil on the response of buried pipeline are analyzed. The numerical results show that the soil rupture mode determines the location of the large deformation or failure of the pipeline, and the plastic deformation of the pipeline occurs at the zone where the plastic deformation or rupture of the overlying soil appears. When the fault dip angle on bedrock is near 90°, two plastic deformation sections of the pipeline appear with the development of overlying soil rupture. And the thicker the overlying soil is, the longer the plastic deformation length of the pipeline is and the less its strain is. The plastic deformation length of the pipeline decreases while its maximum strain increases with the rigidity of overlying soil increasing.

  8. 78 FR 58382 - Notice of Final Federal Agency Actions on the Proposed U.S. 50 Study Crossing Over Sinepauxent...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-23

    ...This notice announces actions taken by the FHWA and other Federal agencies that are final within the meaning of 23 U.S.C. 139(l)(1). The action relates to the U.S. 50 Crossing over Sinepauxent Bay Study from MD 611 to MD 378 and 5th Street to Somerset Street located in the Town of Ocean City, Worcester County, Maryland. This action grants approval for the...

  9. Field-induced superconducting phase of FeSe in the BCS-BEC cross-over.

    PubMed

    Kasahara, Shigeru; Watashige, Tatsuya; Hanaguri, Tetsuo; Kohsaka, Yuhki; Yamashita, Takuya; Shimoyama, Yusuke; Mizukami, Yuta; Endo, Ryota; Ikeda, Hiroaki; Aoyama, Kazushi; Terashima, Taichi; Uji, Shinya; Wolf, Thomas; von Löhneysen, Hilbert; Shibauchi, Takasada; Matsuda, Yuji

    2014-11-18

    Fermi systems in the cross-over regime between weakly coupled Bardeen-Cooper-Schrieffer (BCS) and strongly coupled Bose-Einstein-condensate (BEC) limits are among the most fascinating objects to study the behavior of an assembly of strongly interacting particles. The physics of this cross-over has been of considerable interest both in the fields of condensed matter and ultracold atoms. One of the most challenging issues in this regime is the effect of large spin imbalance on a Fermi system under magnetic fields. Although several exotic physical properties have been predicted theoretically, the experimental realization of such an unusual superconducting state has not been achieved so far. Here we show that pure single crystals of superconducting FeSe offer the possibility to enter the previously unexplored realm where the three energies, Fermi energy εF, superconducting gap Δ, and Zeeman energy, become comparable. Through the superfluid response, transport, thermoelectric response, and spectroscopic-imaging scanning tunneling microscopy, we demonstrate that εF of FeSe is extremely small, with the ratio Δ/εF ~ 1(~0.3) in the electron (hole) band. Moreover, thermal-conductivity measurements give evidence of a distinct phase line below the upper critical field, where the Zeeman energy becomes comparable to εF and Δ. The observation of this field-induced phase provides insights into previously poorly understood aspects of the highly spin-polarized Fermi liquid in the BCS-BEC cross-over regime. PMID:25378706

  10. Genetic structure of desert ground squirrels over a 20-degree-latitude transect from Oregon through the Baja California peninsula.

    PubMed

    Whorley, Joshua R; Alvarez-Castañeda, S Ticul; Kenagy, G J

    2004-09-01

    The genetic structure of populations over a wide geographical area should reflect the demographic and evolutionary processes that have shaped a species across its range. We examined the population genetic structure of antelope ground squirrels (Ammospermophilus leucurus) across the complex of North American deserts from the Great Basin of Oregon to the cape region of the Baja California peninsula. We sampled 73 individuals from 13 major localities over this 2500-km transect, from 43 to 22 degrees north. Our molecular phylogeographical analysis of 555 bp of the mitochondrial cytochrome b gene and 510 bp of the control region revealed great genetic uniformity in a single clade that extends from Oregon to central Baja California. A second distinct clade occupies the southern half of the peninsula. The minimal geographical structure of the northern clade, its low haplotype diversity and the distribution of pairwise differences between haplotypes suggest a rapid northward expansion of the population that must have followed a northward desert habitat shift associated with the most recent Quaternary climate warming and glacial retreat. The higher haplotype diversity within the southern clade and distribution of pairwise differences between haplotypes suggest that the southern clade has a longer, more stable history associated with a southern peninsular refugium. This system, as observed, reflects both historical and contemporary ecological and evolutionary responses to physical environmental gradients within genetically homogeneous populations. PMID:15315683

  11. Genetic architecture of lipid traits changes over time and differs by race: Princeton Lipid Follow-up Study

    PubMed Central

    Woo, Jessica G.; Morrison, John A.; Stroop, Davis M.; Aronson Friedman, Lisa; Martin, Lisa J.

    2014-01-01

    Dyslipidemia is a major risk factor for CVD. Previous studies on lipid heritability have largely focused on white populations assessed after the obesity epidemic. Given secular trends and racial differences in lipid levels, this study explored whether lipid heritability is consistent across time and between races. African American and white nuclear families had fasting lipids measured in the 1970s and 22–30 years later. Heritability was estimated, and bivariate analyses between visits were conducted by race using variance components analysis. A total of 1,454 individuals (age 14.1/40.6 for offspring/parents at baseline; 39.6/66.5 at follow-up) in 373 families (286 white, 87 African American) were included. Lipid trait heritabilities were typically stronger during the 1970s than the 2000s. At baseline, additive genetic variation for LDL was significantly lower in African Americans than whites (P = 0.015). Shared genetic contribution to lipid variability over time was significant in both whites (all P < 0.0001) and African Americans (P ≤ 0.05 for total, LDL, and HDL cholesterol). African American families demonstrated shared environmental contributions to lipid variation over time (all P ≤ 0.05). Lower heritability, lower LDL genetic variance, and durable environmental effects across the obesity epidemic in African American families suggest race-specific approaches are needed to clarify the genetic etiology of lipids. PMID:24859784

  12. Reasoning over genetic variance information in cause-and-effect models of neurodegenerative diseases

    PubMed Central

    Naz, Mufassra; Kodamullil, Alpha Tom

    2016-01-01

    The work we present here is based on the recent extension of the syntax of the Biological Expression Language (BEL), which now allows for the representation of genetic variation information in cause-and-effect models. In our article, we describe, how genetic variation information can be used to identify candidate disease mechanisms in diseases with complex aetiology such as Alzheimer’s disease and Parkinson’s disease. In those diseases, we have to assume that many genetic variants contribute moderately to the overall dysregulation that in the case of neurodegenerative diseases has such a long incubation time until the first clinical symptoms are detectable. Owing to the multilevel nature of dysregulation events, systems biomedicine modelling approaches need to combine mechanistic information from various levels, including gene expression, microRNA (miRNA) expression, protein–protein interaction, genetic variation and pathway. OpenBEL, the open source version of BEL, has recently been extended to match this requirement, and we demonstrate in our article, how candidate mechanisms for early dysregulation events in Alzheimer’s disease can be identified based on an integrative mining approach that identifies ‘chains of causation’ that include single nucleotide polymorphism information in BEL models. PMID:26249223

  13. Formal collaboration between John Innes Pisum collection and USDA-ARS collection over Pisum genetic stocks.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA genetic stock collection is incomplete, only 101 genes (mutations) are represented with no alleles from another 246 published pea genes represented in the collection. This germplasm is desired for pea breeding programs for crop improvement through fundamental studies on pea functional geno...

  14. Estimates for Genetic Variance Components in Reciprocal Recurrent Selection in Populations Derived from Maize Single-Cross Hybrids

    PubMed Central

    dos Reis, Matheus Costa; Pádua, José Maria Villela; Abreu, Guilherme Barbosa; Guedes, Fernando Lisboa; Balbi, Rodrigo Vieira; de Souza, João Cândido

    2014-01-01

    This study was carried out to obtain the estimates of genetic variance and covariance components related to intra- and interpopulation in the original populations (C0) and in the third cycle (C3) of reciprocal recurrent selection (RRS) which allows breeders to define the best breeding strategy. For that purpose, the half-sib progenies of intrapopulation (P11 and P22) and interpopulation (P12 and P21) from populations 1 and 2 derived from single-cross hybrids in the 0 and 3 cycles of the reciprocal recurrent selection program were used. The intra- and interpopulation progenies were evaluated in a 10 × 10 triple lattice design in two separate locations. The data for unhusked ear weight (ear weight without husk) and plant height were collected. All genetic variance and covariance components were estimated from the expected mean squares. The breakdown of additive variance into intrapopulation and interpopulation additive deviations (στ2) and the covariance between these and their intrapopulation additive effects (CovAτ) found predominance of the dominance effect for unhusked ear weight. Plant height for these components shows that the intrapopulation additive effect explains most of the variation. Estimates for intrapopulation and interpopulation additive genetic variances confirm that populations derived from single-cross hybrids have potential for recurrent selection programs. PMID:25009831

  15. Cross-layer ultrasound video streaming over mobile WiMAX and HSUPA networks.

    PubMed

    Alinejad, Ali; Philip, Nada Y; Istepanian, Robert S H

    2012-01-01

    It is well known that the evolution of 4G-based mobile multimedia network systems will contribute significantly to future mobile healthcare (m-health) applications that require high bandwidth and fast data rates. Central to the success of such emerging applications is the compatibility of broadband networks, such as mobile Worldwide Interoperability For Microwave Access (WiMAX) and High-Speed Uplink Packet Access (HSUPA), and especially their rate adaption issues combined with the acceptable real-time medical quality of service requirements. In this paper, we address the relevant challenges of cross-layer design requirements for real-time rate adaptation of ultrasound video streaming in mobile WiMAX and HSUPA networks. A comparative performance analysis of such approach is validated in two experimental m-health test bed systems for both mobile WiMAX and HSUPA networks. The experimental results have shown an improved performance of mobile WiMAX compared to the HSUPA using the same cross-layer optimization approach. PMID:21571613

  16. Development of novel DNA markers for genetic analysis of grey hamsters by cross-species amplification of microsatellites.

    PubMed

    Wang, C; Zhang, S J; Du, X Y; Xu, Y M; Huo, X Y; Liao, L F; Chen, Z W

    2015-01-01

    The grey hamster has been used in biomedical research for decades. However, effective molecular methods for evaluating the genetic structure of this species are lacking, which hinders its wider usage. In this study, we employed cross-amplification of microsatellite loci of species within the same genus by polymerase chain reaction. Loci screened included 107 from the Mongolian gerbil (MG) and 60 from the Chinese hamster (CH); of these, 15 polymorphic loci were identified for the grey hamster. Of the 167 loci screened, 95 (56.9%) with clear bands on agarose gel were initially identified. After sequencing, 74 (77.9%) of these matched the criteria for microsatellite characteristics, including 41 from MG and 33 from CH. Lastly, 15 (20.3%) loci with more than two alleles for each locus were identified through capillary electrophoresis scanning. To justify the applicability of the 15 grey hamster loci, genetic indexes of grey hamsters were evaluated using 46 generations of outbred stock, established 20 years ago, from Xinjiang, China. Mean effective allele numbers and expected heterozygosity of stock were as low as, respectively, 1.2 and 0.14; these were 2.8 and 4.0 times inferior, respectively, to wild grey hamsters. This finding suggests that the genetic structure of the stock-bred population is too weak to resist artificial and natural selection, mutation and genetic drifting. In conclusion, we have developed de novo microsatellite markers for genetic analysis of the grey hamster, providing data and methodology for the enrichment of a genetic library for this species. PMID:26600493

  17. A placebo-controlled, double-blind, cross-over trial of flunarizine in common migraine.

    PubMed

    Sørensen, P S; Hansen, K; Olesen, J

    1986-03-01

    After four weeks of medication-free baseline observation, 29 patients with common migraine randomly received flunarizine (10 mg daily) or placebo for a 16-week period. After four weeks wash-out they crossed treatments for another 16 weeks; 27 patients completed the trial. Compared with placebo, flunarizine significantly reduced the frequency of migraine attacks and the derived headache indices, but the duration and severity of single attacks remained unchanged (Mann-Whitney U-test). The effect of flunarizine increased during the 16-week treatment period and during the last four weeks the number of migraine attacks reduced to 50% compared to the wash-out period. The only side-effect of flunarizine was mild daytime sedation in three patients. It is concluded that flunarizine is a valuable new prophylactic agent for common migraine. PMID:3516409

  18. A new general analytical approach for modeling patterns of genetic differentiation and effective size of subdivided populations over time.

    PubMed

    Hössjer, Ola; Olsson, Fredrik; Laikre, Linda; Ryman, Nils

    2014-12-01

    The main purpose of this paper is to develop a theoretical framework for assessing effective population size and genetic divergence in situations with structured populations that consist of various numbers of more or less interconnected subpopulations. We introduce a general infinite allele model for a diploid, monoecious and subdivided population, with subpopulation sizes varying over time, including local subpopulation extinction and recolonization, bottlenecks, cyclic census size changes or exponential growth. Exact matrix analytic formulas are derived for recursions of predicted (expected) gene identities and gene diversities, identity by descent and coalescence probabilities, and standardized variances of allele frequency change. This enables us to compute and put into a general framework a number of different types of genetically effective population sizes (Ne) including variance, inbreeding, nucleotide diversity, and eigenvalue effective size. General expressions for predictions (gST) of the coefficient of gene differentiation GST are also derived. We suggest that in order to adequately describe important properties of a subdivided population with respect to allele frequency change and maintenance of genetic variation over time, single values of gST and Ne are not enough. Rather, the temporal dynamic patterns of these properties are important to consider. We introduce several schemes for weighting subpopulations that enable effective size and expected genetic divergence to be calculated and described as functions of time, globally for the whole population and locally for any group of subpopulations. The traditional concept of effective size is generalized to situations where genetic drift is confounded by external sources, such as immigration and mutation. Finally, we introduce a general methodology for state space reduction, which greatly decreases the computational complexity of the matrix analytic formulas. PMID:25445736

  19. Children's Sleep and Cognitive Performance: A Cross-Domain Analysis of Change Over Time

    PubMed Central

    Bub, Kristen L.; Buckhalt, Joseph A.; El-Sheikh, Mona

    2012-01-01

    Relations between changes in children's cognitive performance and changes in sleep problems were examined over a 3-year period, and family socioeconomic status, child race/ethnicity, and gender were assessed as moderators of these associations. Participants were 250 second- and third-grade (8–9 years old at Time 1) boys and girls. At each assessment, children's cognitive performance (Verbal Comprehension, Decision Speed) was measured using the Woodcock-Johnson III Tests of Cognitive Abilities, and sleep problems (Sleepiness, Sleep/Wake Problems) were collected via self-report. Individual growth models revealed that children who reported increases in Sleepiness exhibited little growth in Verbal Comprehension over time compared with their peers who reported decreases in Sleepiness, resulting in a nearly 11-point cognitive deficit by the end of the study. These associations were not found for Sleep/Wake Problems or Decision Speed. Child race/ethnicity and gender moderated these associations, with Sleepiness serving as a vulnerability factor for poor cognitive outcomes, especially among African American children and girls. Differences in cognitive performance for children with high and low Sleepiness trajectories ranged from 16 to 19 points for African American children and from 11 to 19 points for girls. Results build substantially on existing literature examining associations between sleep and cognitive functioning in children and are the first to demonstrate that children's sleep trajectories over 3 waves were associated with changes in their cognitive performance over time. PMID:21942668

  20. Children's Sleep and Cognitive Performance: A Cross-Domain Analysis of Change over Time

    ERIC Educational Resources Information Center

    Bub, Kristen L.; Buckhalt, Joseph A.; El-Sheikh, Mona

    2011-01-01

    Relations between changes in children's cognitive performance and changes in sleep problems were examined over a 3-year period, and family socioeconomic status, child race/ethnicity, and gender were assessed as moderators of these associations. Participants were 250 second- and third-grade (8-9 years old at Time 1) boys and girls. At each…

  1. Dental Occlusion in a Split Amazon Indigenous Population: Genetics Prevails over Environment

    PubMed Central

    Normando, David; Faber, Jorge; Guerreiro, João Farias; Abdo Quintão, Cátia Cardoso

    2011-01-01

    Background Studies examining human and nonhuman primates have supported the hypothesis that the recent increase in the occurrence of misalignment of teeth and/or incorrect relation of dental arches, named dental malocclusion, is mainly attributed to the availability of a more processed diet and the reduced need for powerful masticatory action. For the first time on live human populations, genetic and tooth wear influences on occlusal variation were examined in a split indigenous population. The Arara-Iriri people are descendants of a single couple expelled from a larger village. In the resultant village, expansion occurred through the mating of close relatives, resulting in marked genetic cohesion with substantial genetic differences. Methodology/Principal Findings Dental malocclusion, tooth wear and inbreeding coefficient were evaluated. The sample examined was composed of 176 individuals from both villages. Prevalence Ratio and descriptive differences in the outcomes frequency for each developmental stage of the dentition were considered. Statistical differences between the villages were examined using the chi-square test or Fisher's exact statistic. Tooth wear and the inbreeding coefficient (F) between the villages was tested with Mann-Whitney statistics. All the statistics were performed using two-tailed distribution at p≤0.05. The coefficient inbreeding (F) confirmed the frequent incestuous unions among the Arara-Iriri indigenous group. Despite the tooth wear similarities, we found a striking difference in occlusal patterns between the two Arara villages. In the original village, dental malocclusion was present in about one third of the population; whilst in the resultant village, the occurrence was almost doubled. Furthermore, the morphological characteristics of malocclusion were strongly different between the groups. Conclusions/Significance Our findings downplay the widespread influence of tooth wear, a direct evidence of what an individual ate in the

  2. Temperature can shape a cline in polyandry, but only genetic variation can sustain it over time

    PubMed Central

    Taylor, Michelle L.; Price, Tom A.R.; Skeats, Alison

    2016-01-01

    Multiple mating by females (polyandry) is a widespread behavior occurring in diverse taxa, species, and populations. Polyandry can also vary widely within species, and individual populations, so that both monandrous and polyandrous females occur together. Genetic differences can explain some of this intraspecific variation in polyandry, but environmental factors are also likely to play a role. One environmental factor that influences many fundamental biological processes is temperature. Higher temperatures have been shown to directly increase remating in laboratory studies of insects. In the longer term, high temperature could also help to drive the evolution of larger-scale patterns of behavior by changing the context-dependent balance of costs and benefits of polyandry across environments. We examined the relative influence of rearing and mating temperatures on female remating in populations of Drosophila pseudoobscura that show a latitudinal cline in polyandry in nature, using a range of ecologically relevant temperatures. We found that females of all genotypes remated more at cooler temperatures, which fits with the observation of higher average frequencies of polyandry at higher latitudes in this species. However, the impact of temperature was outweighed by the strong genetic control of remating in females in this species. It is likely that genetic factors provide the primary explanation for the latitudinal cline in polyandry in this species. PMID:27004012

  3. Cross-Disorder Genetic Analysis of Tic Disorders, Obsessive-Compulsive, and Hoarding Symptoms.

    PubMed

    Zilhão, Nuno R; Smit, Dirk J; Boomsma, Dorret I; Cath, Danielle C

    2016-01-01

    Hoarding, obsessive-compulsive disorder (OCD), and Tourette's disorder (TD) are psychiatric disorders that share symptom overlap, which might partly be the result of shared genetic variation. Population-based twin studies have found significant genetic correlations between hoarding and OCD symptoms, with genetic correlations varying between 0.1 and 0.45. For tic disorders, studies examining these correlations are lacking. Other lines of research, including clinical samples and GWAS or CNV data to explore genetic relationships between tic disorders and OCD, have only found very modest if any shared genetic variation. Our aim was to extend current knowledge on the genetic structure underlying hoarding, OC symptoms (OCS), and lifetime tic symptoms and, in a trivariate analysis, assess the degree of common and unique genetic factors contributing to the etiology of these disorders. Data have been gathered from participants in the Netherlands Twin Register comprising a total of 5293 individuals from a sample of adult monozygotic (n = 2460) and dizygotic (n = 2833) twin pairs (mean age 33.61 years). The data on Hoarding, OCS, and tic symptoms were simultaneously analyzed in Mplus. A liability threshold model was fitted to the twin data, analyzing heritability of phenotypes and of their comorbidity. Following the criteria for a probable clinical diagnosis in all phenotypes, 6.8% of participants had a diagnosis of probable hoarding disorder (HD), 6.3% of OCS, and 12.8% of any probable lifetime tic disorder. Genetic factors explained 50.4, 70.1, and 61.1% of the phenotypic covariance between hoarding-OCS, hoarding-tics, and OCS-tics, respectively. Substantial genetic correlations were observed between hoarding and OCS (0.41), hoarding and tics (0.35), and between OCS and tics (0.37). These results support the contribution of genetic factors in the development of these disorders and their comorbidity. Furthermore, tics were mostly influenced by specific

  4. Cross-Disorder Genetic Analysis of Tic Disorders, Obsessive–Compulsive, and Hoarding Symptoms

    PubMed Central

    Zilhão, Nuno R.; Smit, Dirk J.; Boomsma, Dorret I.; Cath, Danielle C.

    2016-01-01

    Hoarding, obsessive–compulsive disorder (OCD), and Tourette’s disorder (TD) are psychiatric disorders that share symptom overlap, which might partly be the result of shared genetic variation. Population-based twin studies have found significant genetic correlations between hoarding and OCD symptoms, with genetic correlations varying between 0.1 and 0.45. For tic disorders, studies examining these correlations are lacking. Other lines of research, including clinical samples and GWAS or CNV data to explore genetic relationships between tic disorders and OCD, have only found very modest if any shared genetic variation. Our aim was to extend current knowledge on the genetic structure underlying hoarding, OC symptoms (OCS), and lifetime tic symptoms and, in a trivariate analysis, assess the degree of common and unique genetic factors contributing to the etiology of these disorders. Data have been gathered from participants in the Netherlands Twin Register comprising a total of 5293 individuals from a sample of adult monozygotic (n = 2460) and dizygotic (n = 2833) twin pairs (mean age 33.61 years). The data on Hoarding, OCS, and tic symptoms were simultaneously analyzed in Mplus. A liability threshold model was fitted to the twin data, analyzing heritability of phenotypes and of their comorbidity. Following the criteria for a probable clinical diagnosis in all phenotypes, 6.8% of participants had a diagnosis of probable hoarding disorder (HD), 6.3% of OCS, and 12.8% of any probable lifetime tic disorder. Genetic factors explained 50.4, 70.1, and 61.1% of the phenotypic covariance between hoarding-OCS, hoarding-tics, and OCS-tics, respectively. Substantial genetic correlations were observed between hoarding and OCS (0.41), hoarding and tics (0.35), and between OCS and tics (0.37). These results support the contribution of genetic factors in the development of these disorders and their comorbidity. Furthermore, tics were mostly influenced by specific

  5. Development of novel microsatellite DNA markers by cross-amplification and analysis of genetic variation in gerbils.

    PubMed

    Du, Xiaoyan; Chen, Zhenwen; Li, Wei; Tan, Yuanqing; Lu, Jing; Zhu, Xiangdong; Zhao, Taiyun; Dong, Gang; Zeng, Lin

    2010-01-01

    The objectives of this study are to establish microsatellite loci for the Mongolian gerbil based on mouse microsatellite DNA sequences and to investigate genetic variation in the laboratory gerbil (Capital Medical University, CMU) and 2 wild gerbil populations (from Yin Chuan city [YIN] and the Hohehot Municipality [HOH]). In total, 536 mouse microsatellite markers were chosen to identify polymorphic dinucleotide repeat loci in the gerbil by cross-amplification. Of these markers, 313 (58.39%) have been discretely amplified from the CMU laboratory gerbil and been sequenced. Of the 313 sequenced markers, 130 were confirmed as simple sequence repeat (SSR) loci in the gerbil. In total, 6 of those newly identified loci plus 6 identified in previous reports were used to estimate the genetic polymorphism for 30 laboratory gerbils and 54 wild gerbils (27 each of the HOH and YIN groups). A total of 29 alleles were observed in the 3 populations, and 11 of 12 loci (91.67%) are polymorphic markers. Nei's standard genetic distances of 0.0592 (CMU vs. HOH) and 0.1033 (CMU vs. YIN) were observed. The averages of observed versus expected heterozygosity are 0.5231/0.4008, 0.5051/0.3882, and 0.4825/0.3665 for the YIN, HOH, and CMU populations, respectively. These results show that cross-amplification using mouse microsatellite primers is an efficient way to identify gerbil SSR loci. By using these 12 selected markers, we have demonstrated that genetic variation level within the CMU population is higher than that has been reported previously and are comparable with the levels found in 2 wild populations. PMID:20525768

  6. Genetic structure and bio-climatic modeling support allopatric over parapatric speciation along a latitudinal gradient

    PubMed Central

    2012-01-01

    Background Four of the five species of Telopea (Proteaceae) are distributed in a latitudinal replacement pattern on the south-eastern Australian mainland. In similar circumstances, a simple allopatric speciation model that identifies the origins of genetic isolation within temporal geographic separation is considered as the default model. However, secondary contact between differentiated lineages can result in similar distributional patterns to those arising from a process of parapatric speciation (where gene flow between lineages remains uninterrupted during differentiation). Our aim was to use the characteristic distributional patterns in Telopea to test whether it reflected the evolutionary models of allopatric or parapatric speciation. Using a combination of genetic evidence and environmental niche modelling, we focused on three main questions: do currently described geographic borders coincide with genetic and environmental boundaries; are there hybrid zones in areas of secondary contact between closely related species; did species distributions contract during the last glacial maximum resulting in distributional gaps even where overlap and hybridisation currently occur? Results Total genomic DNA was extracted from 619 individuals sampled from 36 populations representing the four species. Seven nuclear microsatellites (nSSR) and six chloroplast microsatellites (cpSSR) were amplified across all populations. Genetic structure and the signature of admixture in overlap zones was described using the Bayesian clustering methods implemented in STUCTURE and NewHybrids respectively. Relationships between chlorotypes were reconstructed as a median-joining network. Environmental niche models were produced for all species using environmental parameters from both the present day and the last glacial maximum (LGM). The nSSR loci amplified a total of 154 alleles, while data for the cpSSR loci produced a network of six chlorotypes. STRUCTURE revealed an optimum number of five

  7. Imbibition of oil in film form over water present in edges of capillaries with an angular cross section

    SciTech Connect

    Dong, M.; Dullien, F.A.L.; Chatzis, I.

    1995-06-01

    In this paper it is shown, for the first time, that a nonspreading oil can form films over water films present in the edges of pores in a water-wet porous medium. Both the water and the oil wet the solid surface preferentially to air, but water wets the solid preferentially to oil. The mechanism of the film formation is capillary imbibition, i.e., spontaneous displacement of air by the oil, and it is similar to the formation of water films in the edges of a clean glass capillary of angular cross section filled with air. The principal difference is that, whereas the water imbibes over a solid surface, the oil imbibes over a surface consisting partly of water and partly of a solid wetted by oil. It is shown, by a combination of applications of Laplace`s equation of capillarity with the condition of minimum surface free energy, that if a ``critical`` oil film thickness is exceeded by the addition of excess oil, then this excess oil will imbibe over the water film in the edge until the equilibrium critical oil film thickness is established. The equations have been solved by iteration for the critical oil film thickness, using representative values of the parameters involved. Further, it is shown that an oil blob placed in a capillary of polygonal (e.g., square or equilateral triangle) cross section, containing water films in the edges of the capillary, will imbibe in the form of films over the water present in the edges, subject to certain limitations, specified in the paper. The theoretical predictions are supported by photomicrographs showing imbibition of benzene equilibrated with water and a paraffin oil over water present in the edges of a 2D glass micromodel. The spreading coefficient is negative for both systems.

  8. Regional geomagnetic main field and secular variation modelling using ground, satellite and marine cross-over data

    NASA Astrophysics Data System (ADS)

    Talarn, Àngela; Pavón-Carrasco, F. Javier; Miquel Torta, J.; Qamili, Enkelejda

    2014-05-01

    After the good results obtained from an attempt to generate a regional model for the secular variation of the total geomagnetic field for gaining a better knowledge of the field over oceanic regions, we now present a new regional model for the full vector main field and its secular variation from 1960.0 to 2000.0 over the North Atlantic Ocean. The distinct facts of our approach with respect to previous existing global models arise from the new information afforded by a collection and selection of marine cross-over data, along with the techniques that we propose for constructing the regional model, which include uncertainty estimates of the results. The marine data offer the possibility to gain better and robust knowledge of the field over large areas lacked of observatories over periods of time without satellite information. In addition to the marine data, we used observatory and repeat station data in the peripheral areas and satellite data from OERSTED, MAGSAT and the OGO series. All the data passed a rigorous selection in order to reject suspicious data and different random selections of satellite data were applied to reduce the effect of the satellite tracks. Due to the use of different altitude data, we obtained our model using the Revised Spherical Cap Harmonic Analysis (R-SCHA) in space and the penalized cubic B-splines in time. Taking advantage of the orthogonality of the basis functions, being particularly important in the inverse problem approach, we introduced two temporal and spatial regularization matrices with appropriate damping parameters, which are adjusted to assess the best compromise between the data fit and the model roughness. The obtained results show an improvement in terms of root mean square error when the regional model is compared with other global models for those epochs, such as the CM4, highlighting the importance of the use of the cross-over marine data in the oceanic regions.

  9. Cross-Amplification and Validation of SNPs Conserved over 44 Million Years between Seals and Dogs

    PubMed Central

    Hoffman, Joseph I.; Thorne, Michael A. S.; McEwing, Rob; Forcada, Jaume; Ogden, Rob

    2013-01-01

    High-density SNP arrays developed for humans and their companion species provide a rapid and convenient tool for generating SNP data in closely-related non-model organisms, but have not yet been widely applied to phylogenetically divergent taxa. Consequently, we used the CanineHD BeadChip to genotype 24 Antarctic fur seal (Arctocephalus gazella) individuals. Despite seals and dogs having diverged around 44 million years ago, 33,324 out of 173,662 loci (19.2%) could be genotyped, of which 173 were polymorphic and clearly interpretable. Two SNPs were validated using KASP genotyping assays, with the resulting genotypes being 100% concordant with those obtained from the high-density array. Two loci were also confirmed through in silico visualisation after mapping them to the fur seal transcriptome. Polymorphic SNPs were distributed broadly throughout the dog genome and did not differ significantly in proximity to genes from either monomorphic SNPs or those that failed to cross-amplify in seals. However, the nearest genes to polymorphic SNPs were significantly enriched for functional annotations relating to energy metabolism, suggesting a possible bias towards conserved regions of the genome. PMID:23874599

  10. Cross-amplification and validation of SNPs conserved over 44 million years between seals and dogs.

    PubMed

    Hoffman, Joseph I; Thorne, Michael A S; McEwing, Rob; Forcada, Jaume; Ogden, Rob

    2013-01-01

    High-density SNP arrays developed for humans and their companion species provide a rapid and convenient tool for generating SNP data in closely-related non-model organisms, but have not yet been widely applied to phylogenetically divergent taxa. Consequently, we used the CanineHD BeadChip to genotype 24 Antarctic fur seal (Arctocephalus gazella) individuals. Despite seals and dogs having diverged around 44 million years ago, 33,324 out of 173,662 loci (19.2%) could be genotyped, of which 173 were polymorphic and clearly interpretable. Two SNPs were validated using KASP genotyping assays, with the resulting genotypes being 100% concordant with those obtained from the high-density array. Two loci were also confirmed through in silico visualisation after mapping them to the fur seal transcriptome. Polymorphic SNPs were distributed broadly throughout the dog genome and did not differ significantly in proximity to genes from either monomorphic SNPs or those that failed to cross-amplify in seals. However, the nearest genes to polymorphic SNPs were significantly enriched for functional annotations relating to energy metabolism, suggesting a possible bias towards conserved regions of the genome. PMID:23874599

  11. Sampling genetic diversity in the sympatrically and allopatrically speciating Midas cichlid species complex over a 16 year time series

    PubMed Central

    Bunje, Paul ME; Barluenga, Marta; Meyer, Axel

    2007-01-01

    Background Speciation often occurs in complex or uncertain temporal and spatial contexts. Processes such as reinforcement, allopatric divergence, and assortative mating can proceed at different rates and with different strengths as populations diverge. The Central American Midas cichlid fish species complex is an important case study for understanding the processes of speciation. Previous analyses have demonstrated that allopatric processes led to species formation among the lakes of Nicaragua as well as sympatric speciation that is occurring within at least one crater lake. However, since speciation is an ongoing process and sampling genetic diversity of such lineages can be biased by collection scheme or random factors, it is important to evaluate the robustness of conclusions drawn on individual time samples. Results In order to assess the validity and reliability of inferences based on different genetic samples, we have analyzed fish from several lakes in Nicaragua sampled at three different times over 16 years. In addition, this time series allows us to analyze the population genetic changes that have occurred between lakes, where allopatric speciation has operated, as well as between different species within lakes, some of which have originated by sympatric speciation. Focusing on commonly used genetic markers, we have analyzed both DNA sequences from the complete mitochondrial control region as well as nuclear DNA variation at ten microsatellite loci from these populations, sampled thrice in a 16 year time period, to develop a robust estimate of the population genetic history of these diversifying lineages. Conclusion The conclusions from previous work are well supported by our comprehensive analysis. In particular, we find that the genetic diversity of derived crater lake populations is lower than that of the source population regardless of when and how each population was sampled. Furthermore, changes in various estimates of genetic diversity within lakes

  12. Anxiety Trajectories in the Second Half of Life: Genetic and Environmental Contributions over Age

    PubMed Central

    Lee, Lewina O.; Gatz, Margaret; Pedersen, Nancy L.; Prescott, Carol A.

    2015-01-01

    Clinically significant anxiety symptoms are prevalent among the elderly, yet knowledge about the longitudinal course of anxiety symptoms in later life remains scarce. The goals of this study were to (1) characterize age trajectories of state anxiety symptoms in the second half of life, and (2) estimate genetic and environmental contributions to individual differences in the age trajectory of state anxiety. This study was based on data from 1,482 participants in the Swedish Adoption/Twin Study of Aging who were aged 50 and older at their first occasion (512 complete twin pairs, 458 singletons) and had up to six measurement occasions spanning 11 years. Consistent with lifespan developmental theories of age-related emotional change, anxiety symptom levels declined during the transition from midlife to the mid −60s, followed by a mild increase that gradually plateaued in the 80s. There were substantial individual differences in the age trajectory of anxiety. After accounting for effects of sex, cohort, mode of testing and proximity to death, this longitudinal variation was partitioned into biometric sources. Nonshared environmental variance was highest in the late 60s and declined thereafter, whereas genetic variance increased at an accelerated pace from approximately age 60 onward. There was no evidence for effects of rearing or other shared environment on anxiety symptoms in later life. These findings highlight how the etiology of anxiety symptoms changes from midlife to old age. PMID:26751006

  13. Anxiety trajectories in the second half of life: Genetic and environmental contributions over age.

    PubMed

    Lee, Lewina O; Gatz, Margaret; Pedersen, Nancy L; Prescott, Carol A

    2016-02-01

    Clinically significant anxiety symptoms are prevalent among the elderly, yet knowledge about the longitudinal course of anxiety symptoms in later life remains scarce. The goals of this study were to (a) characterize age trajectories of state anxiety symptoms in the second half of life, and (b) estimate genetic and environmental contributions to individual differences in the age trajectory of state anxiety. This study was based on data from 1,482 participants in the Swedish Adoption/Twin Study of Aging who were aged 50 and older at their first occasion (512 complete twin pairs, 458 singletons) and had up to 6 measurement occasions spanning 11 years. Consistent with life span developmental theories of age-related emotional change, anxiety symptom levels declined during the transition from midlife to the mid-60s, followed by a mild increase that gradually plateaued in the 80s. There were substantial individual differences in the age trajectory of anxiety. After accounting for effects of sex, cohort, mode of testing, and proximity to death, this longitudinal variation was partitioned into biometric sources. Nonshared environmental variance was highest in the late 60s and declined thereafter, whereas genetic variance increased at an accelerated pace from approximately age 60 onward. There was no evidence for effects of rearing or other shared environment on anxiety symptoms in later life. These findings highlight how the etiology of anxiety symptoms changes from midlife to old age. PMID:26751006

  14. Merging molecular data for evaluating cross country genetic diversity of pigs.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Integration of molecular data generated by microsatellite panels recommended by FAO around the world should be initiated in order to accomplish objectives stated in the Global Plan of Action for Animal Genetic Resources. To that end microsatellite datasets from U.S. (n=179, including imported Chines...

  15. CFP Positive Progeny from Genetic Crosses of Elite Germplasm with a Transgenic Sugar Beet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resistance to Cercospora leaf spot disease, a serious problem for sugar beet production in most growing regions, has historically not been very amenable to genetic improvement by traditional means since only moderate resistance occurs naturally and it is multigenic with low heritability. Therefore, ...

  16. Belief and disbelief in the existence of genetic risk factors for suicide: cross-cultural comparisons.

    PubMed

    Voracek, Martin

    2007-12-01

    There is evidence for widespread disbelief in the genetics of suicide, despite recent research progress in this area and convergent evidence supporting a role for genetic factors. This study analyzed the beliefs held in 8 samples (total N = 1224) of various types (psychology, medical, and various undergraduates, psychology graduates, and the general population) from 6 countries located on 3 continents (Austria, Canada, Malaysia, Romania, United Kingdom, and the USA). Endorsement rates for the existence of genetic risk factors for suicide ranged from 26% and 30% (Austrian psychology undergraduates and general population) to around 50% (psychology undergraduates in the USA and United Kingdom). In the 8 samples, respondents' sex, age, religiosity, political orientation, and other demographic variables were, for the most part, unrelated, but overall knowledge about suicide throughout was related positively to endorsement rates. Consistent with previous research, across a considerable variety of sample types and cultural settings there was no evidence for a clear majority believing in genetic bases for suicide. PMID:18361135

  17. A Cross-Sectional Behavioral Genetic Analysis of Task Persistence in the Transition to Middle Childhood

    ERIC Educational Resources Information Center

    Deater-Deckard, Kirby; Petrill, Stephen A.; Thompson, Lee A.; DeThorne, Laura S.

    2005-01-01

    Task persistence, measured by a composite score of independent teacher, tester and observer reports, was examined using behavioral genetic analysis. Participants included 92 monozygotic and 137 same-sex dizygotic twin pairs in Kindergarten or 1st grade (4.3 to 7.9 years old). Task persistence was widely distributed, higher among older children,…

  18. Chromosome Fragments in DICTYOSTELIUM DISCOIDEUM Obtained from Parasexual Crosses between Strains of Different Genetic Background

    PubMed Central

    Williams, Keith L.; Robson, Gillian E.; Welker, Dennis L.

    1980-01-01

    The first aneuploid strains of Dictyostelium discoideum have been unambiguously characterized, using cytological and genetic analysis. Three independently isolated, but genetically similar, fragment chromosomes have been observed in segregants from diploids formed between haploid strains derived from the NC4 and V12 isolates of D. discoideum. Once generated, the fragment chromosomes, all of which have V12-derived centromeres, can be maintained in a NC4 genetic background. Genetic evidence is consistent with the view that all three fragment chromosomes studied encompass the region from the centromere to the whiA locus of linkage group II and terminate in the interval between whiA and acrA. From cytological studies, one of the fragment chromosomes consists of approximately half of linkage group II.—We observed no deleterious effect on viability or asexual fruiting-body formation in either haploid or diploid strains carrying an additional incomplete chromosome and hence are disomic or trisomic, respectively, for part of linkage group II. The incomplete chromosome is lost at a frequency of 2 to 3% from disomic and trisomic strains, but surprisingly this loss is not increased in the presence of the haploidizing agent, benlate. A new locus (clyA), whose phenotype is altered colony morphology, is assigned to the region of linkage group II encompassed by the fragment chromosome. PMID:17249037

  19. Cross-fertilization as a reproductive strategy in a tissue flukes Didymosulcus katsuwonicola (Platyhelmintes: Didymozoidae) inferred by genetic analysis.

    PubMed

    Mladineo, Ivona; Tomaš, Marina; Stanić, Rino

    2015-09-01

    Mitochondrial DNA locus cytochrome oxidase I was used to asses intraspecific genetic diversity of a didymozoid species Didymosulcus katsuwonicola. Adult forms of this species live encapsulated in pairs in the gills of the reared Atlantic bluefin tuna (Thunnus thynnus). The life cycle of this food-borne parasites and its migration in the host tissues after releasing from the digestive tract to the definitive site in the gills are unknown. Our goal was to assess whether two encysted didymozoids share the same haplotype, indicative of a common maternal origin, as well as the extent of cross- in respect to self-fertilization strategy. Intraspecific comparison showed high haplotype diversity, while the presence of two matching haplotypes within a single cyst encompassed only 17% of sampled individuals. This infers that cross-fertilization between paired individuals within the cyst is more common mechanism than self-fertilization. Such hermaphroditic parasite's trait suggests the existence of intricate infection and reproduction mechanisms, presumably as an adaptation for successful fulfillment of their indirect life cycle through dissemination of genetically more diverse and consequently more fit offspring. PMID:26138008

  20. A genetic anomaly of oriented collagen biosynthesis and cross-linking: Keratoconus.

    PubMed

    Bourges, J L; Robert, A M; Robert, L

    2015-02-01

    Oriented collagen biosynthesis is one of the major mechanisms involved in tissue and organ formation during development. Corneal biogenesis is one example. Defects in this process lead to anomalies in tissue structure and function. The transparency of cornea and its achievement are a good example as well as its pathological modifications. Keratoconus is one example of this type of pathologies, involving also inappropriate cross-linking of collagen fibers. Among the tentatives to correct this anomaly, the riboflavin-potentiated UV-cross-linking (CXL) of keratoconus corneas appears clinically satisfactory, although none of the experiments and clinical results published prove effective cross-linking. The published results are reviewed in this article. PMID:25468492

  1. Over production of lignocellulosic enzymes of Coriolus versicolor by genetic engineering methodology. Final report

    SciTech Connect

    Williams, A.L.

    1998-07-01

    The project seeks to understand the biological and chemical processes involved in the secretion of the enzyme polyphenol oxidase (PPO) by the hyphae, the basic unit of the filamentous fungus Coriolus versicolor. These studies are made to determine rational strategies for enhanced secretion of PPO, both with the use of recombinant DNA techniques and without. This effort focuses on recombinant DNA techniques to enhance enzyme production. The major thrust of this project was two-fold: to mass produce C. versicolor tyrosinase (polyphenol oxidase) by genetic engineering as well as cultural manipulations; and to utilize PPO as a biocatalyst in the processing of lignocellulose as a renewable energy resource. In this study, the assessment of genomic and cDNA recombinant clones with regards to the overproduction of PPO continued. Further, immunocytochemical techniques were employed to assess the mechanism(s) involved in the secretion of PPO by the hyphae. Also, factors influencing PPO secretion were examined.

  2. Etiology of Obesity Over the Life Span: Ecological and Genetic Highlights from Asian Countries.

    PubMed

    Chong, Pei Nee; Teh, Christinal Pey Wen; Poh, Bee Koon; Noor, Mohd Ismail

    2014-03-01

    Obesity is a worldwide pandemic, and the prevalence rate has doubled since the 1980s. Asian countries are also experiencing the global epidemic of obesity with its related health consequences. The prevalence of overweight and obesity are increasing at an alarming rate across all age groups in Asia. These increases are mainly attributed to rapid economic growth, which leads to socio-economic, nutrition and lifestyle transitions, resulting in a positive energy balance. In addition, fat mass and obesity-associated gene variants, copy number variants in chromosomes and epigenetic modifications have shown positive associations with the risk of obesity among Asians. In this review highlights of prevalence and related ecological and genetic factors that could influence the rapid rise in obesity among Asian populations are discussed. PMID:26626465

  3. Cross layer optimization for cloud-based radio over optical fiber networks

    NASA Astrophysics Data System (ADS)

    Shao, Sujie; Guo, Shaoyong; Qiu, Xuesong; Yang, Hui; Meng, Luoming

    2016-07-01

    To adapt the 5G communication, the cloud radio access network is a paradigm introduced by operators which aggregates all base stations computational resources into a cloud BBU pool. The interaction between RRH and BBU or resource schedule among BBUs in cloud have become more frequent and complex with the development of system scale and user requirement. It can promote the networking demand among RRHs and BBUs, and force to form elastic optical fiber switching and networking. In such network, multiple stratum resources of radio, optical and BBU processing unit have interweaved with each other. In this paper, we propose a novel multiple stratum optimization (MSO) architecture for cloud-based radio over optical fiber networks (C-RoFN) with software defined networking. Additionally, a global evaluation strategy (GES) is introduced in the proposed architecture. MSO can enhance the responsiveness to end-to-end user demands and globally optimize radio frequency, optical spectrum and BBU processing resources effectively to maximize radio coverage. The feasibility and efficiency of the proposed architecture with GES strategy are experimentally verified on OpenFlow-enabled testbed in terms of resource occupation and path provisioning latency.

  4. On the cross-polarization characteristics of crooked wire antennas designed by genetic-algorithms

    NASA Technical Reports Server (NTRS)

    Rengarajan, S. R.; Rahmat-Samii, Y.

    2002-01-01

    In many modern communication applications there is a need for simple circularly polarized antennas for hemispherical coverage with good axial ratio or low value of cross polarization. We revisited the crooked wire antenna because of its simplicity. This paper presents results of our investigation on the crooked wire antennas and other elements.

  5. Cotton Chromosome Substitution Lines Crossed with Cultivars: Genetic Model Evaluation and Seed Trait Analyses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed from Upland cotton, Gossypium hirsutum L., provides a desirable and important nutrition profile. In this study, six seed traits (protein content, oil content, seed hull fiber content, seed index, seed volume, embryo percentage) for F3 hybrids of 13 cotton chromosome substitution lines crossed w...

  6. Genetic mapping of quantitative trait loci governing longevity of Caenorhabditis elegans in recombinant-inbred progeny of a Bergerac-BO x RC301 interstrain cross.

    PubMed Central

    Ayyadevara, S; Ayyadevara, R; Hou, S; Thaden, J J; Shmookler Reis, R J

    2001-01-01

    Recombinant-inbred populations, generated from a cross between Caenorhabditis elegans strains Bergerac-BO and RC301, were used to identify quantitative trait loci (QTL) affecting nematode longevity. Genotypes of young controls and longevity-selected worms (the last-surviving 1% from a synchronously aged population) were assessed at dimorphic transposon-specific markers by multiplex polymerase chain reaction. The power of genetic mapping was enhanced, in a novel experimental design, through map expansion by accrual of recombinations over several generations, internally controlled longevity selection from a genetically heterogeneous, homozygous population, and selective genotyping of extremely long-lived worms. Analysis of individual markers indicated seven life-span QTL, situated near markers on chromosomes I (tcbn2), III (stP127), IV (stP13), V (stP6, stP23, and stP128), and X (stP41). These loci were corroborated, and mapped with increased precision, by nonparametric interval mapping-which supported all loci implicated by single-marker analysis. In addition, a life-span QTL on chromosome II (stP100-stP196), was significant only by interval mapping. Congenic lines were constructed for the longevity QTL on chromosomes III and X, by backcrossing the Bergerac-BO QTL allele into an RC301 background with selection for flanking markers. Survival data for these lines demonstrated consistent and significant effects of each QTL on life span. PMID:11156986

  7. Changes in the genetic structure of Atlantic salmon populations over four decades reveal substantial impacts of stocking and potential resiliency

    PubMed Central

    Perrier, Charles; Guyomard, René; Bagliniere, Jean-Luc; Nikolic, Natacha; Evanno, Guillaume

    2013-01-01

    While the stocking of captive-bred fish has been occurring for decades and has had substantial immediate genetic and evolutionary impacts on wild populations, its long-term consequences have only been weakly investigated. Here, we conducted a spatiotemporal analysis of 1428 Atlantic salmon sampled from 1965 to 2006 in 25 populations throughout France to investigate the influence of stocking on the neutral genetic structure in wild Atlantic salmon (Salmo salar) populations. On the basis of the analysis of 11 microsatellite loci, we found that the overall genetic structure among populations dramatically decreased over the period studied. Admixture rates among populations were highly variable, ranging from a nearly undetectable contribution from donor stocks to total replacement of the native gene pool, suggesting extremely variable impacts of stocking. Depending on population, admixture rates either increased, remained stable, or decreased in samples collected between 1998 and 2006 compared to samples from 1965 to 1987, suggesting either rising, long-lasting or short-term impacts of stocking. We discuss the potential mechanisms contributing to this variability, including the reduced fitness of stocked fish and persistence of wild locally adapted individuals. PMID:23919174

  8. Is Sensory Over-Responsivity Distinguishable from Childhood Behavior Problems? A Phenotypic and Genetic Analysis

    ERIC Educational Resources Information Center

    Van Hulle, Carol A.; Schmidt, Nicole L.; Goldsmith, H. Hill

    2012-01-01

    Background: Although impaired sensory processing accompanies various clinical conditions, the question of its status as an independent disorder remains open. Our goal was to delineate the comorbidity (or lack thereof) between childhood psychopathology and sensory over-responsivity (SOR) in middle childhood using phenotypic and behavior-genetic…

  9. Genome Wide SSR High Density Genetic Map Construction from an Interspecific Cross of Gossypium hirsutum × Gossypium tomentosum

    PubMed Central

    Khan, Muhammad K. R.; Chen, Haodong; Zhou, Zhongli; Ilyas, Muhammad K.; Wang, Xingxing; Cai, Xiaoyan; Wang, Chunying; Liu, Fang; Wang, Kunbo

    2016-01-01

    A high density genetic map was constructed using F2 population derived from an interspecific cross of G. hirsutum × G. tomentosum. The map consisted of 3093 marker loci distributed across all the 26 chromosomes and covered 4365.3 cM of cotton genome with an average inter-marker distance of 1.48 cM. The maximum length of chromosome was 218.38 cM and the minimum was 122.09 cM with an average length of 167.90 cM. A sub-genome covers more genetic distance (2189.01 cM) with an average inter loci distance of 1.53 cM than D sub-genome which covers a length of 2176.29 cM with an average distance of 1.43 cM. There were 716 distorted loci in the map accounting for 23.14% and most distorted loci were distributed on D sub-genome (25.06%), which were more than on A sub-genome (21.23%). In our map 49 segregation hotspots (SDR) were distributed across the genome with more on D sub-genome as compared to A genome. Two post-polyploidization reciprocal translocations of “A2/A3 and A4/A5” were suggested by seven pairs of duplicate loci. The map constructed through these studies is one of the three densest genetic maps in cotton however; this is the first dense genome wide SSR interspecific genetic map between G. hirsutum and G. tomentosum. PMID:27148280

  10. Genetically Engineered Phages: a Review of Advances over the Last Decade.

    PubMed

    Pires, Diana P; Cleto, Sara; Sillankorva, Sanna; Azeredo, Joana; Lu, Timothy K

    2016-09-01

    Soon after their discovery in the early 20th century, bacteriophages were recognized to have great potential as antimicrobial agents, a potential that has yet to be fully realized. The nascent field of phage therapy was adversely affected by inadequately controlled trials and the discovery of antibiotics. Although the study of phages as anti-infective agents slowed, phages played an important role in the development of molecular biology. In recent years, the increase in multidrug-resistant bacteria has renewed interest in the use of phages as antimicrobial agents. With the wide array of possibilities offered by genetic engineering, these bacterial viruses are being modified to precisely control and detect bacteria and to serve as new sources of antibacterials. In applications that go beyond their antimicrobial activity, phages are also being developed as vehicles for drug delivery and vaccines, as well as for the assembly of new materials. This review highlights advances in techniques used to engineer phages for all of these purposes and discusses existing challenges and opportunities for future work. PMID:27250768

  11. Monitoring Hip and Elbow Dysplasia achieved modest genetic improvement of 74 dog breeds over 40 years in USA.

    PubMed

    Hou, Yali; Wang, Yachun; Lu, Xuemei; Zhang, Xu; Zhao, Qian; Todhunter, Rory J; Zhang, Zhiwu

    2013-01-01

    Hip (HD) and Elbow Dysplasia (ED) are two common complex developmental disorders of dogs. In order to decrease their prevalence and severity, the Orthopedic Foundation for Animals (OFA) has a voluntary registry of canine hip and elbow conformation certified by boarded radiologists. However, the voluntarily reports have been severely biased against exposing dogs with problems, especially at beginning period. Fluctuated by additional influential factors such as age, the published raw scores barely showed trends of improvement. In this study, we used multiple-trait mixed model to simultaneously adjust these factors and incorporate pedigree to derive Estimated Breeding Values (EBV). A total of 1,264,422 dogs from 74 breeds were evaluated for EBVs from 760,455 hip scores and 135,409 elbow scores. These EBVs have substantially recovered the reporting bias and the other influences. Clear and steady trends of genetic improvement were observed over the 40 years since 1970. The total genetic improvements were 16.4% and 1.1% of the phenotypic standard deviation for HD and ED, respectively. The incidences of dysplasia were 0.83% and 2.08%, and the heritabilities were estimated as 0.22 and 0.17 for hip and elbow scores, respectively. The genetic correlation between them was 0.12. We conclude that EBV is more effective than reporting raw phenotype. The weak genetic correlation suggested that selection based on hip scores would also slightly improve elbow scores but it is necessary to allocate effort toward improvement of elbow scores alone. PMID:24124555

  12. Genetic parameters for various random regression models to describe total sperm cells per ejaculate over the reproductive lifetime of boars.

    PubMed

    Oh, S H; See, M T; Long, T E; Galvin, J M

    2006-03-01

    The objective of this study was to model the variances and covariances of total sperm cells per ejaculate (TSC) over the reproductive lifetime of AI boars. Data from boars (n = 834) selected for AI were provided by Smithfield Premium Genetics. The total numbers of records and animals were 19,629 and 1,736, respectively. Parameters were estimated for TSC by age of boar classification with a random regression model using the Simplex method and DxMRR procedures. The model included breed, collector, and year-season as fixed effects. Random effects were additive genetic, permanent environmental effect of boar, and residual. Observations were removed when the number of data at a given age of boar classification was < 10 records. Preliminary evaluations showed the best fit with fifth-order polynomials, indicating that the best model would have fifth-order fixed regression and fifth-order random regressions for animal and permanent environmental effects. Random regression models were fitted to evaluate all combinations of first- through seventh-order polynomial covariance functions. Goodness of fit for the models was tested using Akaike's Information Criterion and the Schwarz Criterion. The maximum log likelihood value was observed for sixth-, fifth-, and seventh-order polynomials for fixed, additive genetic, and permanent environmental effects, respectively. However, the best fit as determined by Akaike's Information Criterion and the Schwarz Criterion was by fitting sixth-, fourth-, and seventh-order polynomials; and fourth-, second-, and seventh-order polynomials for fixed, additive genetic, and permanent environmental effects, respectively. Heritability estimates for TSC ranged from 0.27 to 0.48 across age of boar classifications. In addition, heritability for TSC tended to increase with age of boar classification. PMID:16478945

  13. Monitoring Hip and Elbow Dysplasia Achieved Modest Genetic Improvement of 74 Dog Breeds over 40 Years in USA

    PubMed Central

    Zhang, Xu; Zhao, Qian; Todhunter, Rory J.; Zhang, Zhiwu

    2013-01-01

    Hip (HD) and Elbow Dysplasia (ED) are two common complex developmental disorders of dogs. In order to decrease their prevalence and severity, the Orthopedic Foundation for Animals (OFA) has a voluntary registry of canine hip and elbow conformation certified by boarded radiologists. However, the voluntarily reports have been severely biased against exposing dogs with problems, especially at beginning period. Fluctuated by additional influential factors such as age, the published raw scores barely showed trends of improvement. In this study, we used multiple-trait mixed model to simultaneously adjust these factors and incorporate pedigree to derive Estimated Breeding Values (EBV). A total of 1,264,422 dogs from 74 breeds were evaluated for EBVs from 760,455 hip scores and 135,409 elbow scores. These EBVs have substantially recovered the reporting bias and the other influences. Clear and steady trends of genetic improvement were observed over the 40 years since 1970. The total genetic improvements were 16.4% and 1.1% of the phenotypic standard deviation for HD and ED, respectively. The incidences of dysplasia were 0.83% and 2.08%, and the heritabilities were estimated as 0.22 and 0.17 for hip and elbow scores, respectively. The genetic correlation between them was 0.12. We conclude that EBV is more effective than reporting raw phenotype. The weak genetic correlation suggested that selection based on hip scores would also slightly improve elbow scores but it is necessary to allocate effort toward improvement of elbow scores alone. PMID:24124555

  14. Strategies used for genetically modifying bacterial genome: ite-directed mutagenesis, gene inactivation, and gene over-expression*

    PubMed Central

    Xu, Jian-zhong; Zhang, Wei-guo

    2016-01-01

    With the availability of the whole genome sequence of Escherichia coli or Corynebacterium glutamicum, strategies for directed DNA manipulation have developed rapidly. DNA manipulation plays an important role in understanding the function of genes and in constructing novel engineering bacteria according to requirement. DNA manipulation involves modifying the autologous genes and expressing the heterogenous genes. Two alternative approaches, using electroporation linear DNA or recombinant suicide plasmid, allow a wide variety of DNA manipulation. However, the over-expression of the desired gene is generally executed via plasmid-mediation. The current review summarizes the common strategies used for genetically modifying E. coli and C. glutamicum genomes, and discusses the technical problem of multi-layered DNA manipulation. Strategies for gene over-expression via integrating into genome are proposed. This review is intended to be an accessible introduction to DNA manipulation within the bacterial genome for novices and a source of the latest experimental information for experienced investigators. PMID:26834010

  15. Strategies used for genetically modifying bacterial genome: site-directed mutagenesis, gene inactivation, and gene over-expression.

    PubMed

    Xu, Jian-zhong; Zhang, Wei-guo

    2016-02-01

    With the availability of the whole genome sequence of Escherichia coli or Corynebacterium glutamicum, strategies for directed DNA manipulation have developed rapidly. DNA manipulation plays an important role in understanding the function of genes and in constructing novel engineering bacteria according to requirement. DNA manipulation involves modifying the autologous genes and expressing the heterogenous genes. Two alternative approaches, using electroporation linear DNA or recombinant suicide plasmid, allow a wide variety of DNA manipulation. However, the over-expression of the desired gene is generally executed via plasmid-mediation. The current review summarizes the common strategies used for genetically modifying E. coli and C. glutamicum genomes, and discusses the technical problem of multi-layered DNA manipulation. Strategies for gene over-expression via integrating into genome are proposed. This review is intended to be an accessible introduction to DNA manipulation within the bacterial genome for novices and a source of the latest experimental information for experienced investigators. PMID:26834010

  16. The Triple-Code Model for Pancreatic Cancer: Cross Talk Among Genetics, Epigenetics, and Nuclear Structure.

    PubMed

    Lomberk, Gwen A; Urrutia, Raul

    2015-10-01

    Pancreatic adenocarcinoma is painful, generally incurable, and frequently lethal. The current progression model indicates that this cancer evolves by mutations and deletions in key oncogenes and tumor suppressor genes. This article describes an updated, more comprehensive model that includes concepts from the fields of epigenetics and nuclear architecture. Widespread use of next-generation sequencing for identifying genetic and epigenetic changes genome-wide will help identify and validate more and better markers for this disease. Epigenetic alterations are amenable to pharmacologic manipulations, thus this new integrated paradigm will contribute to advance this field from a mechanistic and translational point of view. PMID:26315515

  17. Genetic Control over mtDNA and Its Relationship to Major Depressive Disorder

    PubMed Central

    Cai, Na; Li, Yihan; Chang, Simon; Liang, Jieqin; Lin, Chongyun; Zhang, Xiufei; Liang, Lu; Hu, Jingchu; Chan, Wharton; Kendler, Kenneth S.; Malinauskas, Tomas; Huang, Guo-Jen; Li, Qibin; Mott, Richard; Flint, Jonathan

    2015-01-01

    Summary Control over the number of mtDNA molecules per cell appears to be tightly regulated, but the mechanisms involved are largely unknown. Reversible alterations in the amount of mtDNA occur in response to stress suggesting that control over the amount of mtDNA is involved in stress-related diseases including major depressive disorder (MDD). Using low-coverage sequence data from 10,442 Chinese women to compute the normalized numbers of reads mapping to the mitochondrial genome as a proxy for the amount of mtDNA, we identified two loci that contribute to mtDNA levels: one within the TFAM gene on chromosome 10 (rs11006126, p value = 8.73 × 10−28, variance explained = 1.90%) and one over the CDK6 gene on chromosome 7 (rs445, p value = 6.03 × 10−16, variance explained = 0.50%). Both loci replicated in an independent cohort. CDK6 is thus a new molecule involved in the control of mtDNA. We identify increased rates of heteroplasmy in women with MDD, and show from an experimental paradigm using mice that the increase is likely due to stress. Furthermore, at least one heteroplasmic variant is significantly associated with changes in the amount of mtDNA (position 513, p value = 3.27 × 10−9, variance explained = 0.48%) suggesting site-specific heteroplasmy as a possible link between stress and increase in amount of mtDNA. These findings indicate the involvement of mitochondrial genome copy number and sequence in an organism’s response to stress. PMID:26687620

  18. Genetic Control over mtDNA and Its Relationship to Major Depressive Disorder.

    PubMed

    Cai, Na; Li, Yihan; Chang, Simon; Liang, Jieqin; Lin, Chongyun; Zhang, Xiufei; Liang, Lu; Hu, Jingchu; Chan, Wharton; Kendler, Kenneth S; Malinauskas, Tomas; Huang, Guo-Jen; Li, Qibin; Mott, Richard; Flint, Jonathan

    2015-12-21

    Control over the number of mtDNA molecules per cell appears to be tightly regulated, but the mechanisms involved are largely unknown. Reversible alterations in the amount of mtDNA occur in response to stress suggesting that control over the amount of mtDNA is involved in stress-related diseases including major depressive disorder (MDD). Using low-coverage sequence data from 10,442 Chinese women to compute the normalized numbers of reads mapping to the mitochondrial genome as a proxy for the amount of mtDNA, we identified two loci that contribute to mtDNA levels: one within the TFAM gene on chromosome 10 (rs11006126, p value = 8.73 × 10(-28), variance explained = 1.90%) and one over the CDK6 gene on chromosome 7 (rs445, p value = 6.03 × 10(-16), variance explained = 0.50%). Both loci replicated in an independent cohort. CDK6 is thus a new molecule involved in the control of mtDNA. We identify increased rates of heteroplasmy in women with MDD, and show from an experimental paradigm using mice that the increase is likely due to stress. Furthermore, at least one heteroplasmic variant is significantly associated with changes in the amount of mtDNA (position 513, p value = 3.27 × 10(-9), variance explained = 0.48%) suggesting site-specific heteroplasmy as a possible link between stress and increase in amount of mtDNA. These findings indicate the involvement of mitochondrial genome copy number and sequence in an organism's response to stress. PMID:26687620

  19. Bilateral Repetitive Transcranial Magnetic Stimulation for Auditory Hallucinations in Patients with Schizophrenia: A Randomized Controlled, Cross-over Study

    PubMed Central

    Kim, Eun-Ji; Yeo, Seonguk; Hwang, Inho; Park, Jong-Il; Cui, Yin; Jin, Hong-Mei; Kim, Hyung Tae; Hwang, Tae-Young

    2014-01-01

    Objective A randomized double-blind cross-over trial was conducted in patients with persistent auditory hallucinations (AHs) to investigate whether bilateral repetitive transcranial magnetic stimulation (rTMS) at the temporoparietal area or Broca's area is more effective at high- or low-frequencies compared to a sham condition. Methods Twenty three patients with persistent AHs who remained stable on the same medication for 2 months were enrolled. They were randomized to one of four conditions: low-frequency (1 Hz)-rTMS to the temporoparietal area (L-TP), high-frequency (20 Hz)-rTMS to the temporoparietal area (H-TP), high-frequency (20 Hz)-rTMS to Broca's area (H-B), or sham. Results All the four rTMS conditions resulted in significant decrease in the scores under the auditory hallucination rating scale and hallucination change scale over time. However, there were no significant treatment effects or interaction between time and treatment, suggesting no superior effects of the new paradigms over the sham condition. Conclusion Our findings suggest that bilateral rTMS at the temporoparietal area or Broca's area with high- or low-frequency does not produce superior effects in reducing AHs compared to sham stimulation. PMID:25598827

  20. Botany, genetics and ethnobotany: a crossed investigation on the elusive tapir's diet in French Guiana.

    PubMed

    Hibert, Fabrice; Sabatier, Daniel; Andrivot, Judith; Scotti-Saintagne, Caroline; Gonzalez, Sophie; Prévost, Marie-Françoise; Grenand, Pierre; Chave, Jérome; Caron, Henri; Richard-Hansen, Cécile

    2011-01-01

    While the populations of large herbivores are being depleted in many tropical rainforests, the importance of their trophic role in the ecological functioning and biodiversity of these ecosystems is still not well evaluated. This is due to the outstanding plant diversity that they feed upon and the inherent difficulties involved in observing their elusive behaviour. Classically, the diet of elusive tropical herbivores is studied through the observation of browsing signs and macroscopic analysis of faeces or stomach contents. In this study, we illustrate that the original coupling of classic methods with genetic and ethnobotanical approaches yields information both about the diet diversity, the foraging modalities and the potential impact on vegetation of the largest terrestrial mammal of Amazonia, the lowland tapir. The study was conducted in the Guianan shield, where the ecology of tapirs has been less investigated. We identified 92 new species, 51 new genera and 13 new families of plants eaten by tapirs. We discuss the relative contribution of our different approaches, notably the contribution of genetic barcoding, used for the first time to investigate the diet of a large tropical mammal, and how local traditional ecological knowledge is accredited and valuable for research on the ecology of elusive animals. PMID:21991372

  1. Botany, Genetics and Ethnobotany: A Crossed Investigation on the Elusive Tapir's Diet in French Guiana

    PubMed Central

    Hibert, Fabrice; Sabatier, Daniel; Andrivot, Judith; Scotti-Saintagne, Caroline; Gonzalez, Sophie; Prévost, Marie-Françoise; Grenand, Pierre; Chave, Jérome; Caron, Henri; Richard-Hansen, Cécile

    2011-01-01

    While the populations of large herbivores are being depleted in many tropical rainforests, the importance of their trophic role in the ecological functioning and biodiversity of these ecosystems is still not well evaluated. This is due to the outstanding plant diversity that they feed upon and the inherent difficulties involved in observing their elusive behaviour. Classically, the diet of elusive tropical herbivores is studied through the observation of browsing signs and macroscopic analysis of faeces or stomach contents. In this study, we illustrate that the original coupling of classic methods with genetic and ethnobotanical approaches yields information both about the diet diversity, the foraging modalities and the potential impact on vegetation of the largest terrestrial mammal of Amazonia, the lowland tapir. The study was conducted in the Guianan shield, where the ecology of tapirs has been less investigated. We identified 92 new species, 51 new genera and 13 new families of plants eaten by tapirs. We discuss the relative contribution of our different approaches, notably the contribution of genetic barcoding, used for the first time to investigate the diet of a large tropical mammal, and how local traditional ecological knowledge is accredited and valuable for research on the ecology of elusive animals. PMID:21991372

  2. Maximal fat oxidation rate and cross-over point with respect to lactate thresholds do not have good agreement.

    PubMed

    González-Haro, C

    2011-05-01

    The present cross-sectional study was designed to assess the agreement between maximal fat oxidation rate (maxFAT (OXR)) VS. Lactate Threshold (LT), and CROSS-OVER point (CO (P)) VS. Individual Anaerobic Threshold (IAT) in well-trained athletes. 2 groups of male, well-trained endurance athletes (short-distance triathletes (ST) (n=11), and road cyclists (RC) (n=11)) performed a graded cycle ergometer test to exhaustion, with 4-min stages and 30-W increments. LT, IAT, maxFAT (OXR) and CO (P) were determined for each group. FAT (OXR) and CHO (OXR) were estimated by means of indirect calorimetry and stoichiometric equations. The agreement between maxFAT (OXR) VS. LT, and CO (P) VS. IAT were determined using the Bland-Altman methodology. In spite of the low systematic error (bias) (high accuracy) for CO (P) VS. IAT, the variable error (limits of agreement) was moderate (moderate precision). For maxFAT (OXR) VS. LT the systematic error was moderate (moderate accuracy), and the variable error was moderate to high (moderate to low precision). In conclusion, the data obtained from this study shows that maxFAT (OXR) and CO (P) do not exhibit good agreement with LT and IAT, in male endurance well-trained athletes. Consequently, it is not possible to assume that maxFAT (OXR) VS. LT and CO (P) VS. IAT occurs at the same exercise intensity. PMID:21380968

  3. Improvement of seminal parameters with Prelox: a randomized, double-blind, placebo-controlled, cross-over trial.

    PubMed

    Stanislavov, R; Nikolova, V; Rohdewald, P

    2009-03-01

    In a randomly allocated, double-blind, placebo-controlled, cross-over design, 50 infertile patients were treated for 1 month with placebo or a combination of l-arginine aspartate and Pycnogenol (Prelox). Semen samples were examined at 4 week intervals according to WHO criteria. Treatment with Prelox increased significantly the semen volume, concentration of spermatozoa, percentage of motile spermatozoa and percentage of spermatozoa with normal morphology compared with placebo. The placebo had no influence on the parameters of seminological analysis. Intake of Pycnogenol for 1 month improved the fertility index to normal values. After treatment, the fertility index decreased again to infertile status. No unwanted effects were reported. Prelox seems to be a promising alternative to treat patients with mild infertility. PMID:19142978

  4. The effect of music on discomfort experienced by intensive care unit patients during turning: a randomized cross-over study.

    PubMed

    Cooke, Marie; Chaboyer, Wendy; Schluter, Philip; Foster, Michelle; Harris, Denise; Teakle, Roz

    2010-04-01

    Research consistently demonstrates that intensive care unit (ICU) patients experience pain, discomfort and anxiety despite analgesic and sedative use. The most painful procedure reported by critically ill patients is being turned. Music diminishes anxiety and discomfort in some populations; however, its effect on critically ill patients remains unknown. This research aimed to identify the effect of music on discomfort experienced by ICU patients during turning using a single blind randomized cross-over design. Seventeen post-operative ICU patients were recruited and treatment order randomized. Discomfort and anxiety were measured 15 min before and immediately after two turning procedures. Findings indicated that listening to music 15 min before and during turning did not significantly reduce discomfort or anxiety. Pain management might effectively be addressing discomfort and anxiety experienced during turning. Given previous studies have identified turning as painful, current results are promising and it might be useful to determine if this is widespread. PMID:20487057

  5. Public participation in genetic databases: crossing the boundaries between biobanks and forensic DNA databases through the principle of solidarity

    PubMed Central

    Machado, Helena; Silva, Susana

    2015-01-01

    The ethical aspects of biobanks and forensic DNA databases are often treated as separate issues. As a reflection of this, public participation, or the involvement of citizens in genetic databases, has been approached differently in the fields of forensics and medicine. This paper aims to cross the boundaries between medicine and forensics by exploring the flows between the ethical issues presented in the two domains and the subsequent conceptualisation of public trust and legitimisation. We propose to introduce the concept of ‘solidarity’, traditionally applied only to medical and research biobanks, into a consideration of public engagement in medicine and forensics. Inclusion of a solidarity-based framework, in both medical biobanks and forensic DNA databases, raises new questions that should be included in the ethical debate, in relation to both health services/medical research and activities associated with the criminal justice system. PMID:26139851

  6. Public participation in genetic databases: crossing the boundaries between biobanks and forensic DNA databases through the principle of solidarity.

    PubMed

    Machado, Helena; Silva, Susana

    2015-10-01

    The ethical aspects of biobanks and forensic DNA databases are often treated as separate issues. As a reflection of this, public participation, or the involvement of citizens in genetic databases, has been approached differently in the fields of forensics and medicine. This paper aims to cross the boundaries between medicine and forensics by exploring the flows between the ethical issues presented in the two domains and the subsequent conceptualisation of public trust and legitimisation. We propose to introduce the concept of 'solidarity', traditionally applied only to medical and research biobanks, into a consideration of public engagement in medicine and forensics. Inclusion of a solidarity-based framework, in both medical biobanks and forensic DNA databases, raises new questions that should be included in the ethical debate, in relation to both health services/medical research and activities associated with the criminal justice system. PMID:26139851

  7. A randomised, double- blind, cross-over study investigating the prebiotic effect of agave fructans in healthy human subjects.

    PubMed

    Ramnani, P; Costabile, A; Bustillo, A G R; Gibson, G R

    2015-01-01

    This placebo-controlled, randomised, double-blind, cross-over human feeding study aimed to determine the prebiotic effect of agave fructans. A total of thirty-eight volunteers completed this trial. The treatment consisted of 3 weeks' supplementation with 5 g/d of prebiotic agave fructan (Predilife) or equivalent placebo (maltodextrin), followed by a 2-week washout period following which subjects were crossed over to alternate the treatment arm for 3 weeks followed by a 2-week washout. Faecal samples were collected at baseline, on the last day of treatment (days 22 and 58) and washout (days 36 and 72), respectively. Changes in faecal bacterial populations, SCFA and secretory IgA were assessed using fluorescent in situ hybridisation, GC and ELISA, respectively. Bowel movements, stool consistencies, abdominal comfort and mood changes were evaluated by a recorded daily questionnaire. In parallel, the effect of agave fructans on different regions of the colon using a three-stage continuous culture simulator was studied. Predilife significantly increased faecal bifidobacteria (log10 9·6 (sd 0·4)) and lactobacilli (log10 7·7 (sd 0·8)) compared with placebo (log10 9·2 (sd 0·4); P = 0·00) (log10 7·4 (sd 0·7); P = 0·000), respectively. No change was observed for other bacterial groups tested, SCFA, secretory IgA, and PGE2 concentrations between the treatment and placebo. Denaturing gradient gel electrophoresis analysis indicated that bacterial communities were randomly dispersed and no significant differences were observed between Predilife and placebo treatments. The in vitro models showed similar increases in bifidobacterial and lactobacilli populations to that observed with the in vivo trial. To conclude, agave fructans are well tolerated in healthy human subjects and increased bifidobacteria and lactobacilli numbers in vitro and in vivo but did not influence other products of fermentation. PMID:26090092

  8. Genetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maintaining genetic variation in wild populations of Arctic organisms is fundamental to the long-term persistence of high latitude biodiversity. Variability is important because it provides options for species to respond to changing environmental conditions and novel challenges such as emerging path...

  9. Genetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genus Capsicum represents one of several well characterized Solanaceous genera. A wealth of classical and molecular genetics research is available for the genus. Information gleaned from its cultivated relatives, tomato and potato, provide further insight for basic and applied studies. Early ...

  10. Genetic Linkage Map of a High Yielding FELDA Deli×Yangambi Oil Palm Cross

    PubMed Central

    Seng, Tzer-Ying; Mohamed Saad, Siti Hawa; Chin, Cheuk-Weng; Ting, Ngoot-Chin; Harminder Singh, Rajinder Singh; Qamaruz Zaman, Faridah; Tan, Soon-Guan; Syed Alwee, Sharifah Shahrul Rabiah

    2011-01-01

    Enroute to mapping QTLs for yield components in oil palm, we constructed the linkage map of a FELDA high yielding oil palm (Elaeis guineensis), hybrid cross. The parents of the mapping population are a Deli dura and a pisifera of Yangambi origin. The cross out-yielded the average by 8–21% in four trials all of which yielded comparably to the best current commercial planting materials. The higher yield derived from a higher fruit oil content. SSR markers in the public domain - from CIRAD and MPOB, as well as some developed in FELDA - were used for the mapping, augmented by locally-designed AFLP markers. The female parent linkage map comprised 317 marker loci and the male parent map 331 loci, both in 16 linkage groups each. The number of markers per group ranged from 8–47 in the former and 12–40 in the latter. The integrated map was 2,247.5 cM long and included 479 markers and 168 anchor points. The number of markers per linkage group was 15–57, the average being 29, and the average map density 4.7 cM. The linkage groups ranged in length from 77.5 cM to 223.7 cM, with an average of 137 cM. The map is currently being validated against a closely related population and also being expanded to include yield related QTLs. PMID:22069457

  11. Genetic linkage map of a high yielding FELDA deli×yangambi oil palm cross.

    PubMed

    Seng, Tzer-Ying; Mohamed Saad, Siti Hawa; Chin, Cheuk-Weng; Ting, Ngoot-Chin; Harminder Singh, Rajinder Singh; Qamaruz Zaman, Faridah; Tan, Soon-Guan; Syed Alwee, Sharifah Shahrul Rabiah

    2011-01-01

    Enroute to mapping QTLs for yield components in oil palm, we constructed the linkage map of a FELDA high yielding oil palm (Elaeis guineensis), hybrid cross. The parents of the mapping population are a Deli dura and a pisifera of Yangambi origin. The cross out-yielded the average by 8-21% in four trials all of which yielded comparably to the best current commercial planting materials. The higher yield derived from a higher fruit oil content. SSR markers in the public domain - from CIRAD and MPOB, as well as some developed in FELDA - were used for the mapping, augmented by locally-designed AFLP markers. The female parent linkage map comprised 317 marker loci and the male parent map 331 loci, both in 16 linkage groups each. The number of markers per group ranged from 8-47 in the former and 12-40 in the latter. The integrated map was 2,247.5 cM long and included 479 markers and 168 anchor points. The number of markers per linkage group was 15-57, the average being 29, and the average map density 4.7 cM. The linkage groups ranged in length from 77.5 cM to 223.7 cM, with an average of 137 cM. The map is currently being validated against a closely related population and also being expanded to include yield related QTLs. PMID:22069457

  12. Reproductive performance: at the cross-road of genetics, technologies and environment.

    PubMed

    Vaiman, Daniel

    2014-12-01

    Sexual reproduction depends on a negotiation between the sexes at the level of the cells (gametes), tissue (trophectoderm of the blastocyst and endometrium in the uterus) and organisms (to allow sexual intercourse). This review evaluates new questions linked to sexual reproduction in the biosphere in the context of the 21st century, in light of current knowledge in genetics and epigenetics. It presents the challenge of 'forcing reproductive efficiency' using ineffective gametes, or despite other fertility problems, through medically assisted reproduction and presents the reproductive challenge of high production farm animals, which are in a situation of chronically negative energy balance. It also analyses the situation created by the release of endocrine disruptors into the environment and discusses the possible transgenerational consequences of environmental modifications linked to these compounds. PMID:25472039

  13. Limitations to estimating bacterial cross-species transmission using genetic and genomic markers: inferences from simulation modeling

    PubMed Central

    Benavides, Julio A; Cross, Paul C; Luikart, Gordon; Creel, Scott

    2014-01-01

    Cross-species transmission (CST) of bacterial pathogens has major implications for human health, livestock, and wildlife management because it determines whether control actions in one species may have subsequent effects on other potential host species. The study of bacterial transmission has benefitted from methods measuring two types of genetic variation: variable number of tandem repeats (VNTRs) and single nucleotide polymorphisms (SNPs). However, it is unclear whether these data can distinguish between different epidemiological scenarios. We used a simulation model with two host species and known transmission rates (within and between species) to evaluate the utility of these markers for inferring CST. We found that CST estimates are biased for a wide range of parameters when based on VNTRs and a most parsimonious reconstructed phylogeny. However, estimations of CST rates lower than 5% can be achieved with relatively low bias using as low as 250 SNPs. CST estimates are sensitive to several parameters, including the number of mutations accumulated since introduction, stochasticity, the genetic difference of strains introduced, and the sampling effort. Our results suggest that, even with whole-genome sequences, unbiased estimates of CST will be difficult when sampling is limited, mutation rates are low, or for pathogens that were recently introduced. PMID:25469159

  14. Detection dog efficacy for collecting faecal samples from the critically endangered Cross River gorilla (Gorilla gorilla diehli) for genetic censusing

    PubMed Central

    Arandjelovic, Mimi; Bergl, Richard A.; Ikfuingei, Romanus; Jameson, Christopher; Parker, Megan; Vigilant, Linda

    2015-01-01

    Population estimates using genetic capture–recapture methods from non-invasively collected wildlife samples are more accurate and precise than those obtained from traditional methods when detection and resampling rates are high. Recently, detection dogs have been increasingly used to find elusive species and their by-products. Here we compared the effectiveness of dog- and human-directed searches for Cross River gorilla (Gorilla gorilla diehli) faeces at two sites. The critically endangered Cross River gorilla inhabits a region of high biodiversity and endemism on the border between Nigeria and Cameroon. The rugged highland terrain and their cryptic behaviour make them difficult to study and a precise population size for the subspecies is still lacking. Dog-directed surveys located more fresh faeces with less bias than human-directed survey teams. This produced a more reliable population estimate, although of modest precision given the small scale of this pilot study. Unfortunately, the considerable costs associated with use of the United States-based detection dog teams make the use of these teams financially unfeasible for a larger, more comprehensive survey. To realize the full potential of dog-directed surveys and increase cost-effectiveness, we recommend basing dog-detection teams in the countries where they will operate and expanding the targets the dogs are trained to detect. PMID:26064602

  15. Detection dog efficacy for collecting faecal samples from the critically endangered Cross River gorilla (Gorilla gorilla diehli) for genetic censusing.

    PubMed

    Arandjelovic, Mimi; Bergl, Richard A; Ikfuingei, Romanus; Jameson, Christopher; Parker, Megan; Vigilant, Linda

    2015-02-01

    Population estimates using genetic capture-recapture methods from non-invasively collected wildlife samples are more accurate and precise than those obtained from traditional methods when detection and resampling rates are high. Recently, detection dogs have been increasingly used to find elusive species and their by-products. Here we compared the effectiveness of dog- and human-directed searches for Cross River gorilla (Gorilla gorilla diehli) faeces at two sites. The critically endangered Cross River gorilla inhabits a region of high biodiversity and endemism on the border between Nigeria and Cameroon. The rugged highland terrain and their cryptic behaviour make them difficult to study and a precise population size for the subspecies is still lacking. Dog-directed surveys located more fresh faeces with less bias than human-directed survey teams. This produced a more reliable population estimate, although of modest precision given the small scale of this pilot study. Unfortunately, the considerable costs associated with use of the United States-based detection dog teams make the use of these teams financially unfeasible for a larger, more comprehensive survey. To realize the full potential of dog-directed surveys and increase cost-effectiveness, we recommend basing dog-detection teams in the countries where they will operate and expanding the targets the dogs are trained to detect. PMID:26064602

  16. Sympatric populations of the highly cross-fertile coral species Acropora hyacinthus and Acropora cytherea are genetically distinct.

    PubMed Central

    Márquez, L M; van Oppen, M J H; Willis, B L; Miller, D J

    2002-01-01

    High cross-fertilization rates in vitro and non-monophyletic patterns in molecular phylogenies challenge the taxonomic status of species in the coral genus Acropora. We present data from eight polymorphic allozyme loci that indicate small, but significant, differentiation between sympatric populations of Acropora cytherea and Acropora hyacinthus (F(ST) = 0.025-0.068, p < 0.05), a pair of acroporid corals with very high interspecific fertilization rates in vitro. Although no fixed allelic differences were found between these species, the absence of genetic differentiation between widely allopatric populations suggests that allele frequency differences between A. cytherea and A. hyacinthus in sympatry are biologically significant. By contrast, populations of Acropora tenuis, a species which spawns 2-3 hours earlier and shows low cross-fertilization rates with congeners in vitro, were clearly distinct from A. cytherea and A. hyacinthus (F(ST) = 0.427-0.465, p < 0.05). Moreover, allopatric populations of A. tenuis differed significantly, possibly as a consequence of its relatively short period of larval competency. Our results effectively rule out the possibility that A. hyacinthus and A. cytherea are morphotypes within a single species, and indicate that hybridization occurs relatively infrequently between these taxa in nature. PMID:12065046

  17. Salivary Oxytocin Concentrations in Males following Intranasal Administration of Oxytocin: A Double-Blind, Cross-Over Study

    PubMed Central

    Daughters, Katie; Manstead, Antony S. R.; Hubble, Kelly; Rees, Aled; Thapar, Anita; van Goozen, Stephanie H. M.

    2015-01-01

    The use of intranasal oxytocin (OT) in research has become increasingly important over the past decade. Although researchers have acknowledged a need for further investigation of the physiological effects of intranasal administration, few studies have actually done so. In the present double-blind cross-over study we investigated the longevity of a single 24 IU dose of intranasal OT measured in saliva in 40 healthy adult males. Salivary OT concentrations were significantly higher in the OT condition, compared to placebo. This significant difference lasted until the end of testing, approximately 108 minutes after administration, and peaked at 30 minutes. Results showed significant individual differences in response to intranasal OT administration. To our knowledge this is the largest and first all-male within-subjects design study to demonstrate the impact of intranasal OT on salivary OT concentrations. The results are consistent with previous research in suggesting that salivary OT is a valid matrix for OT measurement. The results also suggest that the post-administration ‘wait-time’ prior to starting experimental tasks could be reduced to 30 minutes, from the 45 minutes typically used, thereby enabling testing during peak OT concentrations. Further research is needed to ascertain whether OT concentrations after intranasal administration follow similar patterns in females, and different age groups. PMID:26669935

  18. Salivary Oxytocin Concentrations in Males following Intranasal Administration of Oxytocin: A Double-Blind, Cross-Over Study.

    PubMed

    Daughters, Katie; Manstead, Antony S R; Hubble, Kelly; Rees, Aled; Thapar, Anita; van Goozen, Stephanie H M

    2015-01-01

    The use of intranasal oxytocin (OT) in research has become increasingly important over the past decade. Although researchers have acknowledged a need for further investigation of the physiological effects of intranasal administration, few studies have actually done so. In the present double-blind cross-over study we investigated the longevity of a single 24 IU dose of intranasal OT measured in saliva in 40 healthy adult males. Salivary OT concentrations were significantly higher in the OT condition, compared to placebo. This significant difference lasted until the end of testing, approximately 108 minutes after administration, and peaked at 30 minutes. Results showed significant individual differences in response to intranasal OT administration. To our knowledge this is the largest and first all-male within-subjects design study to demonstrate the impact of intranasal OT on salivary OT concentrations. The results are consistent with previous research in suggesting that salivary OT is a valid matrix for OT measurement. The results also suggest that the post-administration 'wait-time' prior to starting experimental tasks could be reduced to 30 minutes, from the 45 minutes typically used, thereby enabling testing during peak OT concentrations. Further research is needed to ascertain whether OT concentrations after intranasal administration follow similar patterns in females, and different age groups. PMID:26669935

  19. Constructing the parental linkage phase and the genetic map over distances <1 cM using pooled haploid DNA.

    PubMed

    Gasbarra, Dario; Sillanpää, Mikko J

    2006-02-01

    A new statistical approach for construction of the genetic linkage map and estimation of the parental linkage phase based on allele frequency data from pooled gametic (sperm or egg) samples is introduced. This method can be applied for estimation of recombination fractions (over distances <1 cM) and ordering of large numbers (even hundreds) of closely linked markers. This method should be extremely useful in species with a long generation interval and a large genome size such as in dairy cattle or in forest trees; the conifer species have haploid tissues available in megagametophytes. According to Mendelian expectation, two parental alleles should occur in gametes in 1:1 proportions, if segregation distortion does not occur. However, due to mere sampling variation, the observed proportions may deviate from their expected value in practice. These deviations and their dependence along the chromosome can provide information on the parental linkage phase and on the genetic linkage map. Usefulness of the method is illustrated with simulations. The role of segregation distortion as a source of these deviations is also discussed. The software implementing this method is freely available for research purposes from the authors. PMID:16301209

  20. Retraction of a study on genetically modified corn: Expert investigations should speak louder during controversies over safety.

    PubMed

    Xia, Jufeng; Song, Peipei; Xu, Lingzhong; Tang, Wei

    2015-04-01

    Over the past few years, genetically modified organisms (GMO) have gradually become more familiar after numerous reports of problems with GMO safety, such as genetically modified (GM) potatoes disrupting immunity, GM corn inducing tumors, and GM rice being fed to unwitting Chinese children. Every time, these reports cause panic among the population and lead to objections to GMO in various fora. After each incident, the scientific community has delivered its academic appraisal and refuted rumors through slow and cautious investigations and evaluations. Unfortunately, during each event media outlets quickly scare the public about food safety and ignore the ensuing comments from scientists. Although scientists have investigated each GMO crisis and reached scientific and rational conclusions, they have less ability to disseminate information than the media, so the public is not promptly informed of their rational and objective viewpoints as experts. Thus, scientists need greater ability to disseminate information from scientific investigations and evaluations in order to correct the intemperate reporting by attention-seeking media. PMID:25902952

  1. Crossing the impassable: genetic connections in 20 reef fishes across the eastern Pacific barrier

    PubMed Central

    Lessios, H.A; Robertson, D.R

    2006-01-01

    The ‘impassable’ Eastern Pacific Barrier (EPB), ca 5000 km of deep water separating the eastern from the central Pacific, is the World's widest marine biogeographic barrier. Sequencing of mitochondrial DNA in 20 reef fish morphospecies encountered on both sides of the barrier revealed cryptic speciation in two. Among the other 18 species only two showed significant differentiation (as revealed by haplotype networks and FST statistics) between the eastern and the central Pacific. Coalescence analyses indicated that genetic similarity in the 18 truly transpacific species resulted from different combinations of ages of most recent invasion and of levels of recurrent gene flow, with estimated times of initial separation ranging from approximately 30 000 to 1 Myr (ago). There is no suggestion of simultaneous interruptions of gene flow among the species. Migration across the EPB was previously thought to be exclusively eastward, but our evidence showed two invasions from east to west and eight cases in which subsequent gene flow possibly proceeded in the same direction. Thus, the EPB is sporadically permeable to propagules originating on either side. PMID:16901840

  2. Gene flow in wild chimpanzee populations: what genetic data tell us about chimpanzee movement over space and time.

    PubMed

    Gagneux, P; Gonder, M K; Goldberg, T L; Morin, P A

    2001-06-29

    The isolation of phylogenetically distinct primate immunodeficiency viruses from at least seven wild-born, captive chimpanzees indicates that viruses closely related to HIV-1 may be endemic in some wild chimpanzee populations. The search for the chimpanzee population or populations harbouring these viruses is therefore on. This paper attempts to answer the question of whether or not such populations of chimpanzees are likely to exist at all, and, if so, where they are likely to be found. We summarize what is known about gene flow in wild populations of chimpanzees, both between major phylogeographical subdivisions of the species, and within these subdivisions. Our analysis indicates that hitherto undocumented reproductively isolated chimpanzee populations may in fact exist. This conclusion is based on the observation that, despite limited geographical sampling and limited numbers of genetic loci, conventional notions of the nature and extent of chimpanzee gene flow have recently been substantially revised. Molecular genetic studies using mitochondrial DNA sequences and hypervariable nuclear microsatellite markers have indicated the existence of heretofore undocumented barriers to chimpanzee gene flow. These studies have identified at least one population of chimpanzees genetically distinct enough to be classified into a new subspecies (Pan troglodytes vellerosus). At the same time, they have called into question the long-accepted genetic distinction between eastern chimpanzees (Pan troglodytes schweinfurthii) and western equatorial chimpanzees (Pan troglodytes troglodytes). The same studies have further indicated that gene flow between local populations is more extensive than was previously thought, and follows patterns sometimes inconsistent with those documented through direct behavioural observation. Given the apparently incomplete nature of the current understanding of chimpanzee gene flow in equatorial Africa, it seems reasonable to speculate that a chimpanzee

  3. Cross-shore velocity shear, eddies and heterogeneity in water column properties over fringing coral reefs: West Maui, Hawaii

    NASA Astrophysics Data System (ADS)

    Storlazzi, C. D.; McManus, M. A.; Logan, J. B.; McLaughlin, B. E.

    2006-03-01

    A multi-day hydrographic survey cruise was conducted to acquire spatially extensive, but temporally limited, high-resolution, three-dimensional measurements of currents, temperature, salinity and turbidity off West Maui in the summer of 2003 to better understand coastal dynamics along a complex island shoreline with coral reefs. These data complement long-term, high-resolution tide, wave, current, temperature, salinity and turbidity measurements made at a number of fixed locations in the study area starting in 2001. Analyses of these hydrographic data, in conjunction with numerous field observations, evoke the following conceptual model of water and turbidity flux along West Maui. Wave- and wind-driven flows appear to be the primary control on flow over shallower portions of the reefs while tidal and subtidal currents dominate flow over the outer portions of the reefs and insular shelf. When the direction of these flows counter one another, which is quite common, they cause a zone of cross-shore horizontal shear and often form a front, with turbid, lower-salinity water inshore of the front and clear, higher-salinity water offshore of the front. It is not clear whether these zones of high shear and fronts are the cause or the result of the location of the fore reef, but they appear to be correlated alongshore over relatively large horizontal distances (orders of kilometers). When two flows converge or when a single flow is bathymetrically steered, eddies can be generated that, in the absence of large ocean surface waves, tend to accumulate material. Areas of higher turbidity and lower salinity tend to correlate with regions of poor coral health or the absence of well-developed reefs, suggesting that the oceanographic processes that concentrate and/or transport nutrients, contaminants, low-salinity water or suspended sediment might strongly influence coral reef ecosystem health and sustainability.

  4. Cross-shore velocity shear, eddies and heterogeneity in water column properties over fringing coral reefs: West Maui, Hawaii

    USGS Publications Warehouse

    Storlazzi, C.D.; McManus, M.A.; Logan, J.B.; McLaughlin, B.E.

    2006-01-01

    A multi-day hydrographic survey cruise was conducted to acquire spatially extensive, but temporally limited, high-resolution, three-dimensional measurements of currents, temperature, salinity and turbidity off West Maui in the summer of 2003 to better understand coastal dynamics along a complex island shoreline with coral reefs. These data complement long-term, high-resolution tide, wave, current, temperature, salinity and turbidity measurements made at a number of fixed locations in the study area starting in 2001. Analyses of these hydrographic data, in conjunction with numerous field observations, evoke the following conceptual model of water and turbidity flux along West Maui. Wave- and wind-driven flows appear to be the primary control on flow over shallower portions of the reefs while tidal and subtidal currents dominate flow over the outer portions of the reefs and insular shelf. When the direction of these flows counter one another, which is quite common, they cause a zone of cross-shore horizontal shear and often form a front, with turbid, lower-salinity water inshore of the front and clear, higher-salinity water offshore of the front. It is not clear whether these zones of high shear and fronts are the cause or the result of the location of the fore reef, but they appear to be correlated alongshore over relatively large horizontal distances (orders of kilometers). When two flows converge or when a single flow is bathymetrically steered, eddies can be generated that, in the absence of large ocean surface waves, tend to accumulate material. Areas of higher turbidity and lower salinity tend to correlate with regions of poor coral health or the absence of well-developed reefs, suggesting that the oceanographic processes that concentrate and/or transport nutrients, contaminants, low-salinity water or suspended sediment might strongly influence coral reef ecosystem health and sustainability.

  5. Mechanisms and genetic control of interspecific crossing barriers in Lycopersicon. Final report

    SciTech Connect

    Mutschler, M.A.

    1997-04-30

    Deficiency of Lycopersicon esculentum allele (E) was observed from the RFLP and isozyme data of the F{sub 2} populations derived from the cross L. esculentum x L. pennellii. The genome composition of the F{sub 2} populations containing L. pennellii cytoplasm (F{sub 2}{sup Lp4}) has a lower proportion of the homozygous L. pennellii (PP) genotypes and a higher proportion of heterozygote (EP) genotypes than that of the F{sub 2} populations containing L. esculentum cytoplasm (F{sub 2}{sup Le}). A lower proportion of the L. pennellii alleles (P) was also observed in F{sub 2}{sup Lp4} as compared to F{sub 2}{sup Le} when each marker locus was tested individually. To study the effects of gametic and zygotic selection on segregation distortion, the expected patterns of segregation at a marker locus were derived for ten selection models with gametic or zygotic selection at a hidden linked locus. Segregation distortion caused by four of the selection models studied can be uniquely identified by the patterns of significance expected for the likelihood ratio tests at the marker loci. Comparison of the chromosomal regions associated with specific selection models across populations (of this experiment and previous publications) indicated that the segregation distortion observed in chromosome 10 is associated with zygotic selection affecting both arms of the chromosome, and cytoplasm substitution has the effect of decreasing the segregation distortion on the long arm of the chromosome.

  6. The VEPRO trial: A cross-over randomised controlled trial comparing 2 progressive lenses for patients with presbyopia

    PubMed Central

    Boutron, Isabelle; Touizer, Caroline; Pitrou, Isabelle; Roy, Carine; Ravaud, Philippe

    2008-01-01

    Background The aim of this trial was to compare the effectiveness of two generations of progressive lenses for presbyopia. Methods A multicenter cross-over randomized controlled trial performed in a primary care setting (5 optical dispensaries) was planned. Two categories of progressive lenses were compared: 1) a new-generation lens (i.e., VARILUX PANAMIC ORMA CRIZAL), which is expensive but a supposed improvement in comfort, and 2) an older-generation lens (i.e., VARILUX CONFORT ORMA CRIZAL), which is less expensive and is considered the reference lens. Patients were randomized to wear one generation of progressive lens for 4 weeks, then cross over to wear the other lens for 4 weeks, without knowing the sequence of lenses. Inclusion criteria were 1) age 43–60 years; 2) outpatients already wearing progressive lenses and referred to an optician ophthalmologist for optical correction prescription within the last 6 months; 3) receiving a correction of ≤3 dioptres in cases of associated myopia, hyperopia or astigmatism; 4) understanding and speaking French and able to answer a questionnaire; and 5) giving written consent to participate in the study. The primary outcome was patient preference for one progressive lens at week 8. Secondary outcomes were subjective measures of bifocal visual performance, including a) near visual acuity, b) visual field, c) kinetic visual skills, d) visual adaptability, e) visual comfort, and f) rapidity of adaptation. Results 127 patients were randomized to one of the lens groups. Two patients withdrew prematurely; 98.4% and 97.6% patients who wore the new versus older lenses, respectively, wore their progressive lenses every day during the 4-week period 1 and period 2. The number of participants in each of 5 centres varied from 16 (12.6%) to 35 (27.6%). 57.9% patients preferred the new-generation lenses, 36.5% the older-generation lenses, and 5.6% had no preference (p = 0.01). The two groups did not differ in any of the measures of

  7. The pharmacodynamic equivalence of levothyroxine and liothyronine. A randomized, double blind, cross-over study in thyroidectomized patients

    PubMed Central

    Celi, Francesco S.; Zemskova, Marina; Linderman, Joyce D.; Babar, Nabeel I.; Skarulis, Monica C.; Csako, Gyorgy; Wesley, Robert; Costello, Rene; Penzak, Scott R.; Pucino, Frank

    2009-01-01

    Summary Context The substitution of liothyronine (l-T3) for levothyroxine (l-T4) is commonly employed during thyroid hormone (TH) withdrawal in preparation for diagnostic and therapeutic interventions on thyroid cancer patients. Presently, only limited data are available on the l-T3 for l-T4 therapeutic substitution. Objective To characterize the pharmcodynamic equivalence of l-T3 and l-T4. Design Randomized, double-blind, cross-over intervention study. Setting NIH Clinical Center. Patients 10 thyroidectomized patients. Interventions Study participants were treated with l-T3 or l-T4 with a target TSH ≥0.5≤1.5 mU/l for at least 30 days before undergoing inpatient testing. Following testing, subjects crossed-over according to the same scheme. Main outcome measures Area under the serum concentration-time curve of TSH from 0 to 60 minutes (AUC 0-60) and peak TSH serum concentration (Cmax) following thyrotropin-releasing hormone (TRH) stimulation test, total l-T4 and l-T3 dose (mcg/kg), and l-T4/l-T3 ratio. Results No difference was observed for time 0 TSH values between l-T3 and l-T4 replacement phases (1.48± 0.77 vs. 1.21± 0.62 mU/l, p=0.293) at average daily doses of 40.3±11.3 mcg lT-3 and 115.2±38.5 mcg lT-4, l-T3: l-T4 ratio 0.36±0.06. TRH stimulation test resulted in similar l-T3 vs.l-T4 TSH responses with AUC 0-60 of 326.1 (95% CI 232.6-457.1) and 247.1 (95% CI 153.8-397.1) mU*min /l (p=0.285); and Cmax of 6.83 (95% CI 4.88-9.55) and 5.23 (95% CI 3.31-8.3) mU/l (p=0.383). Conclusions This is the first study addressing the equivalency between l-T3 and l-T4 therapy measured by baseline and TRH-stimulated TSH. The therapeutic substitution of l-T3 for l-T4 was achieved at approximately 1:3 ratio. PMID:20447070

  8. Integrating serological and genetic data to quantify cross-species transmission: brucellosis as a case study.

    PubMed

    Viana, Mafalda; Shirima, Gabriel M; John, Kunda S; Fitzpatrick, Julie; Kazwala, Rudovick R; Buza, Joram J; Cleaveland, Sarah; Haydon, Daniel T; Halliday, Jo E B

    2016-06-01

    Epidemiological data are often fragmented, partial, and/or ambiguous and unable to yield the desired level of understanding of infectious disease dynamics to adequately inform control measures. Here, we show how the information contained in widely available serology data can be enhanced by integration with less common type-specific data, to improve the understanding of the transmission dynamics of complex multi-species pathogens and host communities. Using brucellosis in northern Tanzania as a case study, we developed a latent process model based on serology data obtained from the field, to reconstruct Brucella transmission dynamics. We were able to identify sheep and goats as a more likely source of human and animal infection than cattle; however, the highly cross-reactive nature of Brucella spp. meant that it was not possible to determine which Brucella species (B. abortus or B. melitensis) is responsible for human infection. We extended our model to integrate simulated serology and typing data, and show that although serology alone can identify the host source of human infection under certain restrictive conditions, the integration of even small amounts (5%) of typing data can improve understanding of complex epidemiological dynamics. We show that data integration will often be essential when more than one pathogen is present and when the distinction between exposed and infectious individuals is not clear from serology data. With increasing epidemiological complexity, serology data become less informative. However, we show how this weakness can be mitigated by integrating such data with typing data, thereby enhancing the inference from these data and improving understanding of the underlying dynamics. PMID:26935267

  9. Immunization Associated with Erectile Dysfunction Based on Cross-Sectional and Genetic Analyses

    PubMed Central

    Xu, Jianfeng; Gao, Yong; Tan, Aihua; Yang, Xiaobo; Qin, Xue; Hu, Yanling; Mo, Zengnan

    2014-01-01

    Erectile dysfunction (ED) is a global disease affecting a large number of people. Some studies have found a relationship between low-grade inflammation and ED. We hypothesized that the immune system might play a key role in the outcome of ED. Five immune agents (C3, C4, IgA, IgM, and IgG) were collected based on the Fangchenggang Area Male Health and Examination Survey (FAMHES), using methods of a traditional cross-sectional analysis. Our results repeated the significant association between ED and metabolic syndrome, obesity, and so forth. However, there seemed to be no positive relation between the tested indexes and ED risk in the baseline analysis (C3: P = 0.737; C4: P = 0.274; IgA: P = 0.943; IgG: P = 0.069; IgM: P = 0.985). Then, after adjusting for age and multivariate covariates, a potentially significant association between ED and IgG was discovered (P = 0.025 and P = 0.034, respectively). Meanwhile, in order to describe the development of ED on a gene level, SNP–set kernel-machine association test (SKAT) was applied with the known humoral immune genes involved. The outcomes suggested that PTAFR (binary P value: 0.0096; continuous P value: 0.00869), IL27 (0.0029; 0.1954), CD37 (0.0248; 0.5196), CD40 (0.7146; 0.0413), IL7R (0.1223; 0.0222), PSMB9 (0.1237; 0.0212), and CXCR3 (0.0849; 0.0478) might be key genes in ED, especially IL27, when we restricted the family-wise error rate (FWER) to 0.5. Our study shows that IgG and seven genes (PTAFR, CD37, CD40, IL7R, PSMB9, CXCR3, and especially IL27) might be key factors in the pathogenesis of ED, which could pave the way for future gene and immune therapies. PMID:25343742

  10. Genetic analyses of the major and minor locus groups of bacterial wilt resistance in tobacco using a diallel cross design.

    PubMed

    Qian, Y L; Chen, J; Dong, J J; Wu, Z C; Liu, Y H; Xue, B Y; Shao, F W; Sun, X Y

    2016-01-01

    Tobacco germplasm samples with various levels of resistance to bacterial wilt were selected to construct F1 combinations of parental inbred lines and orthogonal diallel crosses using samples collected in 2009 (15 germplasms), 2010 (15 germplasms), and 2011 (16 germplasms). A total of 1/2P (P + 1) experimental materials were used for analysis. Based on the analyses of major and minor locus groups, genetic effects on the incidence rate and index of bacterial wilt in tobacco were investigated on the 15th and 25th day during the early stage. Significant effects were observed in major locus groups, but not in minor locus groups. Specifically, adjacent major locus groups (J1 = 13,056 and J1 = 13,055; J1 = 14,080 and J1 = 14,079) were detected in both the first and second analyses with considerable effects. Based on the additive effects of minor locus groups on the rate and index of bacterial wilt, the effects on the incidence rates of Yunyan 85, DB101, and RG11 as well as the effects on the disease index of the latter two germplasms reached the maximum. This was consistent with the disease resistance indicators of these tobacco varieties in the field (corresponding broad heritability >20%). Genetic homozygous dominant loci (+ +) increased the rate of bacterial wilt (susceptible), whereas homozygous recessive loci (- -) reduced the index of bacterial wilt (resistant) with considerable additive effects and low dominant effects, suggesting that the inheritance of the bacterial wilt rate and index in tobacco mainly relies on additive inheritance. PMID:26909932