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Sample records for purge inbreeding depression

  1. Inbreeding depression is purged in the invasive insect Harmonia axyridis.

    Science.gov (United States)

    Facon, Benoît; Hufbauer, Ruth A; Tayeh, Ashraf; Loiseau, Anne; Lombaert, Eric; Vitalis, Renaud; Guillemaud, Thomas; Lundgren, Jonathan G; Estoup, Arnaud

    2011-03-08

    Bottlenecks in population size reduce genetic diversity and increase inbreeding, which can lead to inbreeding depression. It is thus puzzling how introduced species, which typically pass through bottlenecks, become such successful invaders. However, under certain theoretical conditions, bottlenecks of intermediate size can actually purge the alleles that cause inbreeding depression. Although this process has been confirmed in model laboratory systems, it has yet to be observed in natural invasive populations. We evaluate whether such purging could facilitate biological invasions by using the world-wide invasion of the ladybird (or ladybug) Harmonia axyridis. We first show that invasive populations endured a bottleneck of intermediate intensity. We then demonstrate that replicate introduced populations experience almost none of the inbreeding depression suffered by native populations. Thus, rather than posing a barrier to invasion as often assumed, bottlenecks, by purging deleterious alleles, can enable the evolution of invaders that maintain high fitness even when inbred. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Does haplodiploidy purge inbreeding depression in rotifer populations?

    Directory of Open Access Journals (Sweden)

    Ana M Tortajada

    Full Text Available BACKGROUND: Inbreeding depression is an important evolutionary factor, particularly when new habitats are colonized by few individuals. Then, inbreeding depression by drift could favour the establishment of later immigrants because their hybrid offspring would enjoy higher fitness. Rotifers are the only major zooplanktonic group where information on inbreeding depression is still critically scarce, despite the fact that in cyclical parthenogenetic rotifers males are haploid and could purge deleterious recessive alleles, thereby decreasing inbreeding depression. METHODOLOGY/PRINCIPAL FINDINGS: We studied the effects of inbreeding in two populations of the cyclical parthenogenetic rotifer Brachionus plicatilis. For each population, we compared both the parental fertilization proportion and F1 fitness components from intraclonal (selfed and interclonal (outcrossed crosses. The parental fertilization proportion was similar for both types of crosses, suggesting that there is no mechanism to avoid selfing. In the F1 generation of both populations, we found evidence of inbreeding depression for the fitness components associated with asexual reproduction; whereas inbreeding depression was only found for one of the two sexual reproduction fitness components measured. CONCLUSIONS/SIGNIFICANCE: Our results show that rotifers, like other major zooplanktonic groups, can be affected by inbreeding depression in different stages of their life cycle. These results suggest that haplodiploidy does not purge efficiently deleterious recessive alleles. The inbreeding depression detected here has important implications when a rotifer population is founded and intraclonal crossing is likely to occur. Thus, during the foundation of new populations inbreeding depression may provide opportunities for new immigrants, increasing gene flow between populations, and affecting genetic differentiation.

  3. Temporal change in inbreeding depression in life-history traits in captive populations of guppy (Poecilia reticulata): evidence for purging?

    Science.gov (United States)

    Larsen, L-K; Pélabon, C; Bolstad, G H; Viken, A; Fleming, I A; Rosenqvist, G

    2011-04-01

    Inbreeding depression, which generally affects the fitness of small populations, may be diminished by purging recessive deleterious alleles when inbreeding persists over several generations. Evidence of purging remains rare, especially because of the difficulties of separating the effects of various factors affecting fitness in small populations. We compared the expression of life-history traits in inbred populations of guppy (Poecilia reticulata) with contemporary control populations over 10 generations in captivity. We estimated inbreeding depression as the difference between the two types of populations at each generation. After 10 generations, the inbreeding coefficient reached a maximum value of 0.56 and 0.16 in the inbred and control populations, respectively. Analysing changes in the life-history traits across generations showed that inbreeding depression in clutch size and offspring survival increased during the first four to six generations in the populations from the inbred treatment and subsequently decreased as expected if purging occurred. Inbreeding depression in two other traits was weaker but showed similar changes across generations. The loss of six populations in the inbred treatment indicates that removal of deleterious alleles also occurred by extinction of populations that presumably harboured high genetic load.

  4. Lifetime inbreeding depression, purging, and mating system evolution in a simultaneous hermaphrodite tapeworm.

    Science.gov (United States)

    Benesh, Daniel P; Weinreich, Friederike; Kalbe, Martin; Milinski, Manfred

    2014-06-01

    Classical theory on mating system evolution suggests that simultaneous hermaphrodites should either outcross if they have high inbreeding depression (ID) or self-fertilize if they have low ID. However, a mixture of selfing and outcrossing persists in many species. Previous studies with the tapeworm Schistocephalus solidus have found worms to self-fertilize some of their eggs despite ID. The probability for selfing to spread depends on the relative fitness of selfers, as well as the genetic basis for ID and whether it can be effectively purged. We bred S. solidus through two consecutive generations of selfing and recorded several fitness correlates over the whole life cycle. After one round of selfing, ID was pronounced, particularly in early-life traits, and the conservatively estimated lifetime fitness of selfed progeny was only 9% that of the outcrossed controls. After a second generation of selfing, ID remained high but was significantly reduced in several traits, which is consistent with the purging of deleterious recessive alleles (the estimated load of lethal equivalents dropped by 48%). Severe ID, even if it can be rapidly purged, likely prevents transitions toward pure selfing in this parasite, although we also cannot exclude the possibility that low-level selfing has undetected benefits.

  5. Reduced mate availability leads to evolution of self-fertilization and purging of inbreeding depression in a hermaphrodite.

    Science.gov (United States)

    Noël, Elsa; Chemtob, Yohann; Janicke, Tim; Sarda, Violette; Pélissié, Benjamin; Jarne, Philippe; David, Patrice

    2016-03-01

    Basic models of mating-system evolution predict that hermaphroditic organisms should mostly either cross-fertilize, or self-fertilize, due to self-reinforcing coevolution of inbreeding depression and outcrossing rates. However transitions between mating systems occur. A plausible scenario for such transitions assumes that a decrease in pollinator or mate availability temporarily constrains outcrossing populations to self-fertilize as a reproductive assurance strategy. This should trigger a purge of inbreeding depression, which in turn encourages individuals to self-fertilize more often and finally to reduce male allocation. We tested the predictions of this scenario using the freshwater snail Physa acuta, a self-compatible hermaphrodite that preferentially outcrosses and exhibits high inbreeding depression in natural populations. From an outbred population, we built two types of experimental evolution lines, controls (outcrossing every generation) and constrained lines (in which mates were often unavailable, forcing individuals to self-fertilize). After ca. 20 generations, individuals from constrained lines initiated self-fertilization earlier in life and had purged most of their inbreeding depression compared to controls. However, their male allocation remained unchanged. Our study suggests that the mating system can rapidly evolve as a response to reduced mating opportunities, supporting the reproductive assurance scenario of transitions from outcrossing to selfing.

  6. Better Fitness in Captive Cuvier’s Gazelle despite Inbreeding Increase: Evidence of Purging?

    OpenAIRE

    Eulalia Moreno; Javier Pérez-González; Juan Carranza; Jordi Moya-Laraño

    2015-01-01

    Captive breeding of endangered species often aims at preserving genetic diversity and to avoid the harmful effects of inbreeding. However, deleterious alleles causing inbreeding depression can be purged when inbreeding persists over several generations. Despite its great importance both for evolutionary biology and for captive breeding programmes, few studies have addressed whether and to which extent purging may occur. Here we undertake a longitudinal study with the largest captive populatio...

  7. Understanding and predicting the fitness decline of shrunk populations: inbreeding, purging, mutation, and standard selection.

    Science.gov (United States)

    García-Dorado, Aurora

    2012-04-01

    The joint consequences of inbreeding, natural selection, and deleterious mutation on mean fitness after population shrinkage are of great importance in evolution and can be critical to the conservation of endangered populations. I present simple analytical equations that predict these consequences, improving and extending a previous heuristic treatment. Purge is defined as the "extra" selection induced by inbreeding, due to the "extra" fitness disadvantage (2d) of homozygotes for (partially) recessive deleterious alleles. Its effect is accounted for by using, instead of the classical inbreeding coefficient f, a purged inbreeding coefficient g that is weighed by the reduction of the frequency of deleterious alleles caused by purging. When the effective size of a large population is reduced to a smaller stable value N (with Nd ≥ 1), the purged inbreeding coefficient after t generations can be predicted as g(t) ≈ [(1 - 1/2N) g(t)(-1) + 1/2N](1 - 2d f(t)(-1)), showing how purging acts upon previously accumulated inbreeding and how its efficiency increases with N. This implies an early fitness decay, followed by some recovery. During this process, the inbreeding depression rate shifts from its ancestral value (δ) to that of the mutation-selection-drift balance corresponding to N (δ*), and standard selection cancels out the inbreeding depression ascribed to δ*. Therefore, purge and inbreeding operate only upon the remaining δ - δ*. The method is applied to the conservation strategy in which family contributions to the breeding pool are equal and is extended to make use of genealogical information. All these predictions are checked using computer simulation.

  8. Better Fitness in Captive Cuvier's Gazelle despite Inbreeding Increase: Evidence of Purging?

    Science.gov (United States)

    Moreno, Eulalia; Pérez-González, Javier; Carranza, Juan; Moya-Laraño, Jordi

    2015-01-01

    Captive breeding of endangered species often aims at preserving genetic diversity and to avoid the harmful effects of inbreeding. However, deleterious alleles causing inbreeding depression can be purged when inbreeding persists over several generations. Despite its great importance both for evolutionary biology and for captive breeding programmes, few studies have addressed whether and to which extent purging may occur. Here we undertake a longitudinal study with the largest captive population of Cuvier's gazelle managed under a European Endangered Species Programme since 1975. Previous results in this population have shown that highly inbred mothers tend to produce more daughters, and this fact was used in 2006 to reach a more appropriate sex-ratio in this polygynous species by changing the pairing strategy (i.e., pairing some inbred females instead of keeping them as surplus individuals in the population). Here, by using studbook data we explore whether purging has occurred in the population by investigating whether after the change in pairing strategy a) inbreeding and homozygosity increased at the population level, b) fitness (survival) increased, and c) the relationship between inbreeding and juvenile survival, was positive. Consistent with the existence of purging, we found an increase in inbreeding coefficients, homozygosity and juvenile survival. In addition, we showed that in the course of the breeding programme the relationship between inbreeding and juvenile survival was not uniform but rather changed over time: it was negative in the early years, flat in the middle years and positive after the change in pairing strategy. We highlight that by allowing inbred individuals to mate in captive stocks we may favour sex-ratio bias towards females, a desirable managing strategy to reduce the surplus of males that force most zoos to use ethical culling and euthanizing management tools. We discuss these possibilities but also acknowledge that many other effects

  9. Better Fitness in Captive Cuvier's Gazelle despite Inbreeding Increase: Evidence of Purging?

    Directory of Open Access Journals (Sweden)

    Eulalia Moreno

    Full Text Available Captive breeding of endangered species often aims at preserving genetic diversity and to avoid the harmful effects of inbreeding. However, deleterious alleles causing inbreeding depression can be purged when inbreeding persists over several generations. Despite its great importance both for evolutionary biology and for captive breeding programmes, few studies have addressed whether and to which extent purging may occur. Here we undertake a longitudinal study with the largest captive population of Cuvier's gazelle managed under a European Endangered Species Programme since 1975. Previous results in this population have shown that highly inbred mothers tend to produce more daughters, and this fact was used in 2006 to reach a more appropriate sex-ratio in this polygynous species by changing the pairing strategy (i.e., pairing some inbred females instead of keeping them as surplus individuals in the population. Here, by using studbook data we explore whether purging has occurred in the population by investigating whether after the change in pairing strategy a inbreeding and homozygosity increased at the population level, b fitness (survival increased, and c the relationship between inbreeding and juvenile survival, was positive. Consistent with the existence of purging, we found an increase in inbreeding coefficients, homozygosity and juvenile survival. In addition, we showed that in the course of the breeding programme the relationship between inbreeding and juvenile survival was not uniform but rather changed over time: it was negative in the early years, flat in the middle years and positive after the change in pairing strategy. We highlight that by allowing inbred individuals to mate in captive stocks we may favour sex-ratio bias towards females, a desirable managing strategy to reduce the surplus of males that force most zoos to use ethical culling and euthanizing management tools. We discuss these possibilities but also acknowledge that many

  10. Better Fitness in Captive Cuvier’s Gazelle despite Inbreeding Increase: Evidence of Purging?

    Science.gov (United States)

    Moreno, Eulalia; Pérez-González, Javier; Carranza, Juan; Moya-Laraño, Jordi

    2015-01-01

    Captive breeding of endangered species often aims at preserving genetic diversity and to avoid the harmful effects of inbreeding. However, deleterious alleles causing inbreeding depression can be purged when inbreeding persists over several generations. Despite its great importance both for evolutionary biology and for captive breeding programmes, few studies have addressed whether and to which extent purging may occur. Here we undertake a longitudinal study with the largest captive population of Cuvier's gazelle managed under a European Endangered Species Programme since 1975. Previous results in this population have shown that highly inbred mothers tend to produce more daughters, and this fact was used in 2006 to reach a more appropriate sex-ratio in this polygynous species by changing the pairing strategy (i.e., pairing some inbred females instead of keeping them as surplus individuals in the population). Here, by using studbook data we explore whether purging has occurred in the population by investigating whether after the change in pairing strategy a) inbreeding and homozygosity increased at the population level, b) fitness (survival) increased, and c) the relationship between inbreeding and juvenile survival, was positive. Consistent with the existence of purging, we found an increase in inbreeding coefficients, homozygosity and juvenile survival. In addition, we showed that in the course of the breeding programme the relationship between inbreeding and juvenile survival was not uniform but rather changed over time: it was negative in the early years, flat in the middle years and positive after the change in pairing strategy. We highlight that by allowing inbred individuals to mate in captive stocks we may favour sex-ratio bias towards females, a desirable managing strategy to reduce the surplus of males that force most zoos to use ethical culling and euthanizing management tools. We discuss these possibilities but also acknowledge that many other effects

  11. A Genetic Interpretation of the Variation in Inbreeding Depression

    OpenAIRE

    2005-01-01

    Inbreeding depression is expected to play an important but complicated role in evolution. If we are to understand the evolution of inbreeding depression (i.e., purging), we need quantitative genetic interpretations of its variation. We introduce an experimental design in which sires are mated to multiple dams, some of which are unrelated to the sire but others are genetically related owing to an arbitrary number of prior generations of selfing or sib-mating. In this way we introduce the conce...

  12. Inbreeding and inbreeding depression in endangered red wolves (Canis rufus).

    Science.gov (United States)

    Brzeski, Kristin E; Rabon, David R; Chamberlain, Michael J; Waits, Lisette P; Taylor, Sabrina S

    2014-09-01

    In natural populations, the expression and severity of inbreeding depression can vary widely across taxa. Describing processes that influence the extent of inbreeding and inbreeding depression aid in our understanding of the evolutionary history of mating systems such as cooperative breeding and nonrandom mate selection. Such findings also help shape wildlife conservation theory because inbreeding depression reduces the viability of small populations. We evaluated the extent of inbreeding and inbreeding depression in a small, re-introduced population of red wolves (Canis rufus) in North Carolina. Since red wolves were first re-introduced in 1987, pedigree inbreeding coefficients (f) increased considerably and almost every wild born wolf was inbred (average f = 0.154 and max f = 0.383). The large inbreeding coefficients were due to both background relatedness associated with few founders and numerous close relative matings. Inbreeding depression was most evident for adult body size and generally absent for direct fitness measures such as reproductive success and survival; no lethal equivalents (LE = 0.00) were detected in juvenile survival. The lack of strong inbreeding depression in direct measures of fitness could be due to a founder effect or because there were no outbred individuals for comparison. Our results highlight the variable expression of inbreeding depression across traits and the need to measure a number of different traits when evaluating inbreeding depression in a wild population. © 2014 John Wiley & Sons Ltd.

  13. Feed-backs among inbreeding, inbreeding depression in sperm traits and sperm competition can drive evolution of costly polyandry.

    Science.gov (United States)

    Bocedi, Greta; Reid, Jane M

    2017-09-12

    Ongoing ambitions are to understand the evolution of costly polyandry and its consequences for species ecology and evolution. Emerging patterns could stem from feed-back dynamics between the evolving mating system and its genetic environment, defined by interactions among kin including inbreeding. However, such feed-backs are rarely considered in non-selfing systems. We use a genetically-explicit model to demonstrate a mechanism by which inbreeding depression can select for polyandry to mitigate the negative consequences of mating with inbred males rather than avoiding inbreeding. Specifically, given inbreeding depression in sperm traits, costly polyandry evolved to ensure female fertility, without requiring explicit inbreeding avoidance. We show the mechanisms behind two main feed-backs. First, resulting sperm competition caused evolution of sperm traits and further mitigated the negative effect of inbreeding depression on female fertility. Second, the evolving mating system fed back to decrease population-wide homozygosity, and hence inbreeding. However, net overall reduction was small due to compound effects on the variances in sex-specific reproductive success and paternity skew. Purging of deleterious mutations did not eliminate inbreeding depression in sperm traits and hence selection for polyandry. Polyandry evolution, both directly and through sperm competition, might consequently facilitate evolutionary rescue for populations experiencing sudden increases in inbreeding. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  14. Efficiency of selection, as measured by single nucleotide polymorphism variation, is dependent on inbreeding rate in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Demontis, Ditte; Pertoldi, Cino; Loeschcke, Volker

    2009-01-01

    It is often hypothesized that slow inbreeding causes less inbreeding depression than fast inbreeding at the same absolute level of inbreeding. Possible explanations for this phenomenon include the more efficient purging of deleterious alleles and more efficient selection for heterozygote...

  15. A simple method to account for natural selection when predicting inbreeding depression.

    Science.gov (United States)

    García-Dorado, Aurora

    2008-11-01

    It has been widely appreciated that natural selection opposes the progress of inbreeding in small populations, thus limiting the actual inbreeding depression for fitness traits. However, no method to account for the consequences of this process has been given so far. I give a simple and intuitive method to predict inbreeding depression, taking into account the increase in selection efficiency against recessive alleles during inbreeding. It is based on the use of a "purged inbreeding coefficient" g(t) that accounts for the reduction of the probability of the deleterious homozygotes caused by the excess d of detrimental effect for deleterious alleles in the homozygous condition over its additive expectation. It is shown that the effect of purging can be important even for relatively small populations. For between-loci variable deleterious effects, accurate predictions can be obtained using the effective homozygous deleterious excess d(e), which can be estimated experimentally and is robust against variation of the ancestral effective population size. The method can be extended to any trait and it is used to predict the evolution of the mean viability or fecundity in a conservation program with equal or random family contributions.

  16. Measuring inbreeding and inbreeding depression on pig growth from pedigree or SNP-derived metrics.

    Science.gov (United States)

    Silió, L; Rodríguez, M C; Fernández, A; Barragán, C; Benítez, R; Óvilo, C; Fernández, A I

    2013-10-01

    Multilocus homozygosity, measured as the proportion of the autosomal genome in homozygous genotypes or in runs of homozygosity, was compared with the respective pedigree inbreeding coefficients in 64 Iberian pigs genotyped using the Porcine SNP60 Beadchip. Pigs were sampled from a set of experimental animals with a large inbreeding variation born in a closed strain with a completely recorded multi-generation genealogy. Individual inbreeding coefficients calculated from pedigree were strongly correlated with the different SNP-derived metrics of homozygosity (r = 0.814-0.919). However, unequal correlations between molecular and pedigree inbreeding were observed at chromosomal level being mainly dependent on the number of SNPs and on the correlation between heterozygosities measured across different loci. A panel of 192 SNPs of intermediate frequencies was selected for genotyping 322 piglets to test inbreeding depression on postweaning growth performance (daily gain and weight at 90 days). The negative effects on these traits of homozygosities calculated from the genotypes of 168 quality-checked SNPs were similar to those of inbreeding coefficients. The results support that few hundreds of SNPs may be useful for measuring inbreeding and inbreeding depression, when the population structure or the mating system causes a large variance of inbreeding. © 2013 Blackwell Verlag GmbH.

  17. Magnitude and timing of inbreeding depression in Scots pine (Pinus sylvestris L.)

    NARCIS (Netherlands)

    Koelewijn, H.P.; Koski, V.; Savolainen, O.

    1999-01-01

    Inbreeding depression is a major selective force favoring outcrossing in flowering plants. However, some self- fertilization should weaken the harmful effects of inbreeding by exposing deleterious alleles to selection. This study examines the maintenance of inbreeding depression in the predominantly

  18. Evidence of inbreeding depression on human height.

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    Ruth McQuillan

    Full Text Available Stature is a classical and highly heritable complex trait, with 80%-90% of variation explained by genetic factors. In recent years, genome-wide association studies (GWAS have successfully identified many common additive variants influencing human height; however, little attention has been given to the potential role of recessive genetic effects. Here, we investigated genome-wide recessive effects by an analysis of inbreeding depression on adult height in over 35,000 people from 21 different population samples. We found a highly significant inverse association between height and genome-wide homozygosity, equivalent to a height reduction of up to 3 cm in the offspring of first cousins compared with the offspring of unrelated individuals, an effect which remained after controlling for the effects of socio-economic status, an important confounder (χ(2 = 83.89, df = 1; p = 5.2 × 10(-20. There was, however, a high degree of heterogeneity among populations: whereas the direction of the effect was consistent across most population samples, the effect size differed significantly among populations. It is likely that this reflects true biological heterogeneity: whether or not an effect can be observed will depend on both the variance in homozygosity in the population and the chance inheritance of individual recessive genotypes. These results predict that multiple, rare, recessive variants influence human height. Although this exploratory work focuses on height alone, the methodology developed is generally applicable to heritable quantitative traits (QT, paving the way for an investigation into inbreeding effects, and therefore genetic architecture, on a range of QT of biomedical importance.

  19. Evidence of inbreeding depression but not inbreeding avoidance in a natural house sparrow population.

    Science.gov (United States)

    Billing, Anna M; Lee, Aline M; Skjelseth, Sigrun; Borg, Asa A; Hale, Matthew C; Slate, Jon; Pärn, Henrik; Ringsby, Thor H; Saether, Bernt-Erik; Jensen, Henrik

    2012-03-01

    Inbreeding is common in small and threatened populations and often has a negative effect on individual fitness and genetic diversity. Thus, inbreeding can be an important factor affecting the persistence of small populations. In this study, we investigated the effects of inbreeding on fitness in a small, wild population of house sparrows (Passer domesticus) on the island of Aldra, Norway. The population was founded in 1998 by four individuals (one female and three males). After the founder event, the adult population rapidly increased to about 30 individuals in 2001. At the same time, the mean inbreeding coefficient among adults increased from 0 to 0.04 by 2001 and thereafter fluctuated between 0.06 and 0.10, indicating a highly inbred population. We found a negative effect of inbreeding on lifetime reproductive success, which seemed to be mainly due to an effect of inbreeding on annual reproductive success. This resulted in selection against inbred females. However, the negative effect of inbreeding was less strong in males, suggesting that selection against inbred individuals is at least partly sex specific. To examine whether individuals avoided breeding with close relatives, we compared observed inbreeding and kinship coefficients in the population with those obtained from simulations of random mating. We found no significant differences between the two, indicating weak or absent inbreeding avoidance. We conclude that there was inbreeding depression in our population. Despite this, birds did not seem to actively avoid mating with close relatives, perhaps as a consequence of constraints on mating possibilities in such a small population.

  20. Trait specific consequences of fast and slow inbreeding: lessonsfrom captive populations of Drosophila melanogaster

    DEFF Research Database (Denmark)

    Mikkelsen, Karina Aarup; Loeschcke, Volker; Kristensen, Torsten Nygaard

    2010-01-01

    The increased homozygosity due to inbreeding leads to expression of deleterious recessive alleles, which may cause inbreeding depression in small populations. The severity of inbreeding depression has been suggested to depend on the rate of inbreeding, with slower inbreeding being more effective...... in purging deleterious alleles of smaller effect. The effectiveness of purging is however dependent on various factors such as the effect of the deleterious, recessive alleles, the genetic background of inbreeding depression and the environment in which purging occurs. Investigations have shown inconclusive...... results as to whether purging efficiently diminish inbreeding depression. Here we used an ecologically relevant inbreeding coefficient (f ≈ 0.25) and generated ten slow and ten fast inbred lines of Drosophila melanogaster by keeping the effective population size constant at respectively 32 and 2 for 19...

  1. Inbreeding depression in red deer calves

    National Research Council Canada - National Science Library

    Walling, Craig A; Nussey, Daniel H; Morris, Alison; Clutton-Brock, Tim H; Kruuk, Loeske E B; Pemberton, Josephine M

    2011-01-01

    .... Here we investigated the consequences of variation in inbreeding coefficient for three juvenile traits, birth date, birth weight and first year survival, in a wild population of red deer, considering...

  2. Can multilocus heterozygosity reveal inbreeding depression?

    Science.gov (United States)

    Syukri, F; Nakajima, T; Nakajima, M

    2016-07-01

    Inbred lines of fish have been widely exploited as model organisms to determine the effect of inbreeding, which is often closely related to fitness such as endurance and productivity compared to morphological traits. Until now, much is unknown about the effects of inbreeding to fish. In the present study, inbred lines of guppies were used to examine the inbreeding effect on morphological traits corresponding to genotype variation. Two strains, called AY and NA1, were selected from the closed culture system. Both strains showed different levels of inbreeding coefficients when compared to microsatellite markers. The AY strain was less inbred as compared to NA1 strain. However, correlation between the standard lengths with multilocus heterozygosity (MLH) at the individual level was observed in the AY, but not in the NA1 strain. This indicated that highly inbred animals have higher similarity in morphological traits as compared to less inbred ones. The inbreeding process showed the importance of heterozygosity, even in laboratory-reared animals. This experiment illustrated the effects of inbreeding towards morphological and genetic changes. ?

  3. Experimental evidence that high levels of inbreeding depress sperm competitiveness.

    Science.gov (United States)

    Zajitschek, S R K; Lindholm, A K; Evans, J P; Brooks, R C

    2009-06-01

    The effects of inbreeding on sperm quantity and quality are among the most dramatic examples of inbreeding depression. The extent to which inbreeding depression results in decreased fertilization success of a male's sperm, however, remains largely unknown. This task is made more difficult by the fact that other factors, such as cryptic female choice, male sperm allocation and mating order, can also drive patterns of paternity. Here, we use artificial insemination to eliminate these extraneous sources of variation and to measure the effects of inbreeding on the competitiveness of a male's sperm. We simultaneously inseminated female guppies (Poecilia reticulata) with equal amounts of sperm from an outbred (f = 0) male and either a highly (f = 0.59) or a moderately inbred (f = 0.25) male. Highly inbred males sired significantly fewer offspring than outbred males, but share of paternity did not differ between moderately inbred and outbred males. These findings therefore confirm that severe inbreeding can impair the competitiveness of sperm, but suggest that in the focal population inbreeding at order of a brother-sister mating does not reduce a male's sperm competitiveness.

  4. ARTICLE - Inbreeding depression in castor bean (Ricinus communis L. progenies

    Directory of Open Access Journals (Sweden)

    Milton Krieger

    2012-12-01

    Full Text Available The purpose of this study was to investigate inbreeding depression (DE in castor bean. From a population derived from the Guarani cultivar, 60 mother plants were sampled. Three types of progenies were obtained from each one: from self-pollination (AU, from crosses (CR and from open pollination (PL. Grain yield of the progenies was evaluated in two locations. There was a strong interaction of progenies x locations, which led to obtaining estimates within each location. Broad variation was observed in inbreeding depression, with mean values of 6.7% and 13.4%, comparing AU progenies with PL progenies. It was observed that the population has high potential for selecting promising inbred lines. The frequency of mother plants generating progenies with simultaneous high general combination capacity and low inbreeding depression was low. Recurrent selection will increase the occurrence of parent plants associating these two properties, which is necessary for obtaining superior synthetic varieties.

  5. Pedigree error due to extra-pair reproduction substantially biases estimates of inbreeding depression.

    Science.gov (United States)

    Reid, Jane M; Keller, Lukas F; Marr, Amy B; Nietlisbach, Pirmin; Sardell, Rebecca J; Arcese, Peter

    2014-03-01

    Understanding the evolutionary dynamics of inbreeding and inbreeding depression requires unbiased estimation of inbreeding depression across diverse mating systems. However, studies estimating inbreeding depression often measure inbreeding with error, for example, based on pedigree data derived from observed parental behavior that ignore paternity error stemming from multiple mating. Such paternity error causes error in estimated coefficients of inbreeding (f) and reproductive success and could bias estimates of inbreeding depression. We used complete "apparent" pedigree data compiled from observed parental behavior and analogous "actual" pedigree data comprising genetic parentage to quantify effects of paternity error stemming from extra-pair reproduction on estimates of f, reproductive success, and inbreeding depression in free-living song sparrows (Melospiza melodia). Paternity error caused widespread error in estimates of f and male reproductive success, causing inbreeding depression in male and female annual and lifetime reproductive success and juvenile male survival to be substantially underestimated. Conversely, inbreeding depression in adult male survival tended to be overestimated when paternity error was ignored. Pedigree error stemming from extra-pair reproduction therefore caused substantial and divergent bias in estimates of inbreeding depression that could bias tests of evolutionary theories regarding inbreeding and inbreeding depression and their links to variation in mating system. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  6. Inbreeding depression of 28 maize elite open pollinated varieties

    Directory of Open Access Journals (Sweden)

    Cleso Antônio Patto Pacheco

    2002-01-01

    Full Text Available The study of inbreeding depression is important for breeding strategies such as use of inbred progenies or extraction of inbreed lines. A diallel of 28 maize open-pollinated varieties was evaluated in 10 environments in the early 1990s. At the same time, S1 populations for each of the 28 varieties were evaluated in the same 10 experiments (environments. Yield reductions of the populations from S0 to S1 (mean of the 10 environments, varied from 34.6% (CMS-01 to 59.2% (CMS-30, with an average of 49.1%. Inbreeding depression was greater in populations with a wider genetic base, which had never been exposed to inbreeding (CMS-30, BR-107, PH4, Cunha, Saracura, Nitrodent, and Nitroflint. Inbred lines with greater yield means should be obtained from the BR-105, BR-111, CMS-01, CMS-03, BR-106, CMS-14c, and CMS-28 populations. The use of parameter estimates generated by analysis of inbreeding depression, allow to make inferences about frequencies of deleterious alleles in the population. The frequencies of favorable alleles in the parents can be obtained by diallel analysis. The association of these two types of information, can provide a better interpretation of the genetic parameters and also can improve the process of selection of parents for either an intra- or an inter-populational breeding program.

  7. Sibling competition does not exacerbate inbreeding depression in the burying beetle Nicrophorus vespilloides.

    Science.gov (United States)

    Pilakouta, N; Sieber, D J; Smiseth, P T

    2016-04-01

    Inbreeding results from matings between relatives and can cause a reduction in offspring fitness, known as inbreeding depression. Previous work has shown that a wide range of environmental stresses, such as extreme temperatures, starvation and parasitism, can exacerbate inbreeding depression. It has recently been argued that stresses due to intraspecific competition should have a stronger effect on the severity of inbreeding depression than stresses due to harsh physical conditions. Here, we tested whether an increase in the intensity of sibling competition can exacerbate inbreeding depression in the burying beetle Nicrophorus vespilloides. We used a 2 × 3 factorial design with offspring inbreeding status (outbred or inbred) and brood size (5, 20, or 40 larvae) as the two factors. We found a main effect of inbreeding status, as inbred larvae had lower survival than outbred larvae, and a main effect of brood size, as larvae in large broods had lower survival and mass than larvae in medium-sized broods. However, there was no effect of the interaction between inbreeding status and brood size, suggesting that sibling competition did not influence the severity of inbreeding depression. Since we focused on sibling competition within homogeneous broods of either inbred or outbred larvae, we cannot rule out possible effects of sibling competition on inbreeding depression in mixed paternity broods comprising of both inbred and outbred offspring. More information on whether and when sibling competition might influence inbreeding depression can help advance our understanding of the causes underlying variation in the severity of inbreeding depression.

  8. Molecular and pedigree measures of relatedness provide similar estimates of inbreeding depression in a bottlenecked population.

    Science.gov (United States)

    Townsend, S M; Jamieson, I G

    2013-04-01

    Individual-based estimates of the degree of inbreeding or parental relatedness from pedigrees provide a critical starting point for studies of inbreeding depression, but in practice wild pedigrees are difficult to obtain. Because inbreeding increases the proportion of genomewide loci that are identical by descent, inbreeding variation within populations has the potential to generate observable correlations between heterozygosity measured using molecular markers and a variety of fitness related traits. Termed heterozygosity-fitness correlations (HFCs), these correlations have been observed in a wide variety of taxa. The difficulty of obtaining wild pedigree data, however, means that empirical investigations of how pedigree inbreeding influences HFCs are rare. Here, we assess evidence for inbreeding depression in three life-history traits (hatching and fledging success and juvenile survival) in an isolated population of Stewart Island robins using both pedigree- and molecular-derived measures of relatedness. We found results from the two measures were highly correlated and supported evidence for significant but weak inbreeding depression. However, standardized effect sizes for inbreeding depression based on the pedigree-based kin coefficients (k) were greater and had smaller standard errors than those based on molecular genetic measures of relatedness (RI), particularly for hatching and fledging success. Nevertheless, the results presented here support the use of molecular-based measures of relatedness in bottlenecked populations when information regarding inbreeding depression is desired but pedigree data on relatedness are unavailable. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  9. Evidence for inbreeding depression and pre-copulatory, but not post copulatory inbreeding avoidance in the cabbage beetle Colaphellus bowringi.

    Directory of Open Access Journals (Sweden)

    XingPing Liu

    Full Text Available Inbreeding is known to have adverse effects on fitness-related traits in a range of insect species. A series of theoretical and experimental studies have suggested that polyandrous insects could avoid the cost of inbreeding via pre-copulatory mate choice and/or post-copulatory mechanisms. We looked for evidence of pre-copulatory inbreeding avoidance using female mate preference trials, in which females were given the choice of mating with either of two males, a sibling and a non-sibling. We also tested for evidence of post-copulatory inbreeding avoidance by conducting double mating experiments, in which four sibling females were mated with two males sequentially, either two siblings, two non-siblings or a sibling and a non-sibling in either order. We identified substantial inbreeding depression: offspring of females mated to full siblings had lower hatching success, slower development time from egg to adult, lower survival of larval and pupal stages, and lower adult body mass than the offspring of females mated to non-sibling males. We also found evidence of pre-copulatory inbreeding avoidance, as females preferred to mate with non-sibling males. However, we did not find any evidence of post-copulatory inbreeding avoidance: egg hatching success of females mating to both sibling and non-sibling males were consistent with sperm being used without bias in relation to mate relatedness. Our results suggest that this cabbage beetle has evolved a pre-copulatory mechanism to avoid matings between close relative, but that polyandry is apparently not an inbreeding avoidance mechanism in C. bowringi.

  10. A major QTL affects temperature sensitive adult lethality and inbreeding depression in life span in Drosophila melanogaster.

    DEFF Research Database (Denmark)

    Vermeulen, Corneel J.; Bijlsma, R.; Loeschcke, Volker

    2008-01-01

    Background The study of inbreeding depression has major relevance for many disciplines, including conservation genetics and evolutionary biology. Still, the molecular genetic basis of this phenomenon remains poorly characterised, as knowledge on the mechanistic causes of inbreeding depression...... and the molecular properties of genes that give rise to or modulate its deleterious effects is lacking. These questions warrant the detailed study of genetic loci giving rise to inbreeding depression. However, the complex and polygenic nature of general inbreeding depression makes this a daunting task. Study...... This demonstrates that analysis of large conditional lethal effects is a viable strategy for delineating genes which are sensitive to inbreeding depression....

  11. A comparison of inbreeding Depression in Tropical and Widespread Drosophila Species

    DEFF Research Database (Denmark)

    Bechsgaard, Jesper Smærup; Hoffmann, Ary A; Sgró, Carla

    2013-01-01

    The evolutionary history of widespread and specialized species is likely to cause a different genetic architecture of key ecological traits in the two species group. This may affect how these two groups respond to inbreeding. Here we investigate inbreeding effects in traits related to performance...... in 5 widespread and 5 tropical restricted species of Drosophila with aim of testing whether the two species groups suffered differently from inbreeding depression. The traits investigated wwere egg-to-adult viability, develpmental time and resistance to heat, vold and desiccation. Our results showed...... that levels of inbreeding depression were species and trait specific and did not differ between the species groups for stress resistance traits. However, for the life history traits developmental time and egg-to-adult viability, more inbreeding depression was observed in the tropical species. The results...

  12. When does female multiple mating evolve to adjust inbreeding? Effects of inbreeding depression, direct costs, mating constraints, and polyandry as a threshold trait.

    Science.gov (United States)

    Duthie, A Bradley; Bocedi, Greta; Reid, Jane M

    2016-09-01

    Polyandry is often hypothesized to evolve to allow females to adjust the degree to which they inbreed. Multiple factors might affect such evolution, including inbreeding depression, direct costs, constraints on male availability, and the nature of polyandry as a threshold trait. Complex models are required to evaluate when evolution of polyandry to adjust inbreeding is predicted to arise. We used a genetically explicit individual-based model to track the joint evolution of inbreeding strategy and polyandry defined as a polygenic threshold trait. Evolution of polyandry to avoid inbreeding only occurred given strong inbreeding depression, low direct costs, and severe restrictions on initial versus additional male availability. Evolution of polyandry to prefer inbreeding only occurred given zero inbreeding depression and direct costs, and given similarly severe restrictions on male availability. However, due to its threshold nature, phenotypic polyandry was frequently expressed even when strongly selected against and hence maladaptive. Further, the degree to which females adjusted inbreeding through polyandry was typically very small, and often reflected constraints on male availability rather than adaptive reproductive strategy. Evolution of polyandry solely to adjust inbreeding might consequently be highly restricted in nature, and such evolution cannot necessarily be directly inferred from observed magnitudes of inbreeding adjustment. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

  13. Analysis of founder-specific inbreeding depression on birth weight in Ripollesa lambs.

    Science.gov (United States)

    Casellas, J; Piedrafita, J; Caja, G; Varona, L

    2009-01-01

    Although inbreeding (F) is a topic of major concern in animal breeding, estimates of inbreeding depression are usually obtained by modeling the overall F coefficient of each individual, without considering that the recessive (deleterious) genetic load of a given population may be unevenly distributed among the founder genomes. The founder-specific partial F coefficient is calculated as the identity-by-descent probability at any given autosomal locus related to a particular founder and allows a more detailed analysis of inbreeding depression on productive traits. Within this context, birth BW data from 2,459 Ripollesa lambs were analyzed under a hierarchical animal model without F-related covariates (model 0), with inbreeding depression modeled by the overall F coefficient (model F1), or by the partial F coefficient of 9 founders that made a relevant contribution to the population inbreeding (model F2). A straightforward empirical Bayes factor (BF) was developed for testing statistical relevance of each F-related covariate, in which greater-than-1 values favored the model including the covariate. The deviance information criterion (DIC) clearly supported model F1 (5,767.8) rather than model 0 (5,771.2), suggesting that inbreeding depression had a relevant influence on birth BW data. The linear effect of inbreeding depression was statistically relevant in model F1 (BF = 2.52 x 10(35)), with lamb birth BW declining by -13.6 g with each 1% F increase. The quadratic effect of inbreeding depression was almost null in model F1 (BF = 0.02), as suggested by the reduction in DIC (5,766.9) when this effect was removed from model F1. On the other hand, model F2 provided a similar DIC (5,767.9) value, with this parameter decreasing to 5,764.7 when nonrelevant founder-specific inbreeding depression effects were removed. Substantial heterogeneity in founder-specific inbreeding depression was reported by model F2, in which estimates for 4 of the 9 founders did not differ from zero

  14. Investigating Inbreeding Depression for Heat Stress Tolerance in the Model Organism "Drosophila Melanogaster"

    Science.gov (United States)

    Pedersen, Kamilla Sofie; Pedersen, Louise Dybdahl; Sorensen, Anders Christian; Nielsen, Anna Busch; Kristensen, Torsten Nygaard

    2012-01-01

    Mating between closely related individuals often causes reduced fitness, which is termed "inbreeding depression". Inbreeding is, therefore, a threat towards the persistence of animal and plant populations. Here we present methods and results from a practical for high-school and first-year university students and discuss learning outcomes…

  15. Investigating Inbreeding Depression for Heat Stress Tolerance in the Model Organism "Drosophila Melanogaster"

    Science.gov (United States)

    Pedersen, Kamilla Sofie; Pedersen, Louise Dybdahl; Sorensen, Anders Christian; Nielsen, Anna Busch; Kristensen, Torsten Nygaard

    2012-01-01

    Mating between closely related individuals often causes reduced fitness, which is termed "inbreeding depression". Inbreeding is, therefore, a threat towards the persistence of animal and plant populations. Here we present methods and results from a practical for high-school and first-year university students and discuss learning outcomes…

  16. Investigating Inbreeding Depression for Heat Stress Tolerance in the Model Organism "Drosophila Melanogaster"

    Science.gov (United States)

    Pedersen, Kamilla Sofie; Pedersen, Louise Dybdahl; Sorensen, Anders Christian; Nielsen, Anna Busch; Kristensen, Torsten Nygaard

    2012-01-01

    Mating between closely related individuals often causes reduced fitness, which is termed "inbreeding depression". Inbreeding is, therefore, a threat towards the persistence of animal and plant populations. Here we present methods and results from a practical for high-school and first-year university students and discuss learning outcomes of the…

  17. Inbreeding depression in two seed-feeding beetles, Callosobruchus maculatus and Stator limbatus (Coleoptera: Chrysomelidae).

    Science.gov (United States)

    Fox, C W; Scheibly, K L; Smith, B P; Wallin, W G

    2007-02-01

    Inbreeding depression is well documented in insects but the degree to which inbreeding depression varies among populations within species, and among traits within populations, is poorly studied in insects other than Drosophila. Inbreeding depression was examined in two long-term laboratory colonies of the seed beetle, Callosobruchus maculatus (Fabricius), which are used frequently as models for experiments in ecology, evolution and behaviour. Inbreeding depression in these laboratory colonies are compared with one recently field-collected population of a different seed beetle, Stator limbatus Horn. Inbreeding reduced embryogenesis, egg hatch and larval survival in both species, such that eggs produced by sib matings were >17% less likely to produce an adult offspring. Inbred larvae also took 4-6% longer to develop to emergence in both species. Inbreeding depression varied among the measured traits but did not differ between the two populations of C. maculatus for any trait, despite the large geographic distance between source populations (western Africa vs. southern India). Inbreeding depression was similar in magnitude between C. maculatus and S. limbatus. This study demonstrates that these laboratory populations of C. maculatus harbour substantial genetic loads, similar to the genetic load of populations of S. limbatus recently collected from the field.

  18. The environmental dependence of inbreeding depression in a wild bird population.

    Directory of Open Access Journals (Sweden)

    Marta Szulkin

    Full Text Available BACKGROUND: Inbreeding depression occurs when the offspring produced as a result of matings between relatives show reduced fitness, and is generally understood as a consequence of the elevated expression of deleterious recessive alleles. How inbreeding depression varies across environments is of importance for the evolution of inbreeding avoidance behaviour, and for understanding extinction risks in small populations. However, inbreeding-by-environment (IxE interactions have rarely been investigated in wild populations. METHODOLOGY/PRINCIPAL FINDINGS: We analysed 41 years of breeding events from a wild great tit (Parus major population and used 11 measures of the environment to categorise environments as relatively good or poor, testing whether these measures influenced inbreeding depression. Although inbreeding always, and environmental quality often, significantly affected reproductive success, there was little evidence for statistically significant I x E interactions at the level of individual analyses. However, point estimates of the effect of the environment on inbreeding depression were sometimes considerable, and we show that variation in the magnitude of the I x E interaction across environments is consistent with the expectation that this interaction is more marked across environmental axes with a closer link to overall fitness, with the environmental dependence of inbreeding depression being elevated under such conditions. Hence, our analyses provide evidence for an environmental dependence of the inbreeding x environment interaction: effectively an I x E x E. CONCLUSIONS/SIGNIFICANCE: Overall, our analyses suggest that I x E interactions may be substantial in wild populations, when measured across relevant environmental contrasts, although their detection for single traits may require very large samples, or high rates of inbreeding.

  19. Monitoring inbreeding trends and inbreeding depression for economically important traits of Holstein cattle in Iran

    National Research Council Canada - National Science Library

    Rokouei, M; Vaez Torshizi, R; Moradi Shahrbabak, M; Sargolzaei, M; Sørensen, A.C

    2010-01-01

    Pedigree information of 852,443 registered Holstein cows and bulls, collected by the Animal Breeding Center of Iran from 1971 to 2007, was used to calculate inbreeding coefficients and their effect...

  20. Inbreeding depresses sperm competitiveness, but not fertilization or mating success in male Tribolium castaneum

    Science.gov (United States)

    Michalczyk, Łukasz; Martin, Oliver Y.; Millard, Anna L.; Emerson, Brent C.; Gage, Matthew J. G.

    2010-01-01

    As populations decline to levels where reproduction among close genetic relatives becomes more probable, subsequent increases in homozygous recessive deleterious expression and/or loss of heterozygote advantage can lead to inbreeding depression. Here, we measure how inbreeding across replicate lines of the flour beetle Tribolium castaneum impacts on male reproductive fitness in the absence or presence of male–male competition. Effects on male evolution from mating pattern were removed by enforcing monogamous mating throughout. After inbreeding across eight generations, we found that male fertility in the absence of competition was unaffected. However, we found significant inbreeding depression of sperm competitiveness: non-inbred males won 57 per cent of fertilizations in competition, while inbred equivalents only sired 42 per cent. We also found that the P2 ‘offence’ role in sperm competition was significantly more depressed under inbreeding than sperm ‘defence’ (P1). Mating behaviour did not explain these differences, and there was no difference in the viability of offspring sired by inbred or non-inbred males. Sperm length variation was significantly greater in the ejaculates of inbred males. Our results show that male ability to achieve normal fertilization success was not depressed under strong inbreeding, but that inbreeding depression in these traits occurred when conditions of sperm competition were generated. PMID:20554548

  1. Inbreeding depression on beef cattle traits: estimates, linearity of effects and heterogeneity among sire-families.

    Science.gov (United States)

    Carolino, Nuno; Gama, Luis T

    2008-01-01

    Records from up to 19 054 registered cows and 10 297 calves in 155 herds of the Alentejana cattle breed were used to study the effects of individual (Fi) and maternal (Fm) inbreeding on reproductive, growth and carcass traits, as well as assessing the importance of non-linear associations between inbreeding and performance, and evaluating the differences among sire-families in the effect of Fi and Fm on calf weight at 7 months of age (W7M). Overall, regression coefficients of performance traits on inbreeding were small, indicating a minor but still detrimental effect of both Fi and Fm on most traits. The traits with the highest percentage impact of Fi were total number of calvings through life and calf weight at 3 months of age (W3M), followed by longevity and number of calves produced up to 7 years, while the highest effect of Fm was on W3M. Inbreeding depression on feed efficiency and carcass traits was extremely small and not significant. No evidence was found of a non-linear association between inbreeding and performance for the traits analyzed. Large differences were detected among sire-families in inbreeding depression on W7M, for both Fi and Fm, encouraging the possibility of incorporating sire effects on inbreeding depression into selection decisions.

  2. Monitoring inbreeding trends and inbreeding depression for economically important traits of Holstein cattle in Iran

    DEFF Research Database (Denmark)

    Rokouei, M; Torshizi, R Vaez; Shahrbabak, M Moradi

    2010-01-01

    Pedigree information of 852,443 registered Holstein cows and bulls, collected by the Animal Breeding Center of Iran from 1971 to 2007, was used to calculate inbreeding coefficients and their effect on production, reproduction, somatic cell count, calving ease, and longevity traits. The average in...

  3. The different sources of variation in inbreeding depression, heterosis and outbreeding depression in a metapopulation of Physa acuta.

    Science.gov (United States)

    Escobar, Juan Sebastián; Nicot, Antoine; David, Patrice

    2008-11-01

    Understanding how parental distance affects offspring fitness, i.e., the effects of inbreeding and outbreeding in natural populations, is a major goal in evolutionary biology. While inbreeding is often associated with fitness reduction (inbreeding depression), interpopulation outcrossing may have either positive (heterosis) or negative (outbreeding depression) effects. Within a metapopulation, all phenomena may occur with various intensities depending on the focal population (especially its effective size) and the trait studied. However, little is known about interpopulation variation at this scale. We here examine variation in inbreeding depression, heterosis, and outbreeding depression on life-history traits across a full-life cycle, within a metapopulation of the hermaphroditic snail Physa acuta. We show that all three phenomena can co-occur at this scale, although they are not always expressed on the same traits. A large variation in inbreeding depression, heterosis, and outbreeding depression is observed among local populations. We provide evidence that, as expected from theory, small and isolated populations enjoy higher heterosis upon outcrossing than do large, open populations. These results emphasize the need for an integrated theory accounting for the effects of both deleterious mutations and genetic incompatibilities within metapopulations and to take into account the variability of the focal population to understand the genetic consequences of inbreeding and outbreeding at this scale.

  4. The effects of selective history and environmental heterogeneity on inbreeding depression in experimental populations of Drosophila melanogaster.

    Science.gov (United States)

    Long, Tristan A F; Rowe, Locke; Agrawal, Aneil F

    2013-04-01

    Inbreeding depression varies considerably among populations, but only some aspects of this variation have been thoroughly studied. Because inbreeding depression requires genetic variation, factors that influence the amount of standing variation can affect the magnitude of inbreeding depression. Environmental heterogeneity has long been considered an important contributor to the maintenance of genetic variation, but its effects on inbreeding depression have been largely ignored by empiricists. Here we compare inbreeding depression, measured in two environments, for 20 experimental populations of Drosophila melanogaster that have been maintained under four different selection regimes, including two types of environmentally homogeneous selection and two types environmentally heterogeneous selection. In line with theory, we find considerably higher inbreeding depression in populations from heterogeneous selection regimes. We also use our data set to test whether inbreeding depression is correlated with either stress or the phenotypic coefficient of variation (CV), as suggested by some recent studies. Though both of these factors are significant predictors of inbreeding depression in our study, there is an effect of assay environment on inbreeding depression that cannot be explained by either stress or CV.

  5. Inbreeding depression under drought stress in the rare endemic Echium wildpretii (Boraginaceae on Tenerife, Canary islands.

    Directory of Open Access Journals (Sweden)

    Janosch Sedlacek

    Full Text Available How climate-change induced environmental stress may alter the effects of inbreeding in patchy populations of rare species is poorly understood. We investigated the fitness of progeny from experimental self- and cross-pollinations in eight populations of different size of Echium wildpretii, a rare endemic plant of the arid subalpine zone of the Canarian island of Tenerife. As control treatments we used open pollination and autonomous selfing. The seed set of open-pollinated flowers was 55% higher than that of autonomously selfed flowers, showing the importance of animal pollination for reproductive success. The seed set, seed mass and germination rate of seedlings of hand-selfed flowers was similar to that of hand-crossed flowers, indicating weak inbreeding depression (seed set -4.4%, seed mass -4.1%, germination -7.3%. Similarly, under normal watering there were no significant effects of inbreeding on seedling survival (-3.0%. However, under low watering of seedlings inbreeding depression was high (survival -50.2%. Seed set of open- and hand-outcrossed-pollinated flowers was higher in large than in small populations, possibly due to more frequent biparental inbreeding in the latter. However, later measures of progeny fitness were not significantly influenced by population size. We predict that increasing drought duration and frequency due to climate change and reductions of population sizes may increase inbreeding depression in this charismatic plant species and thus threaten its future survival in the longer term.

  6. Inbreeding depression under drought stress in the rare endemic Echium wildpretii (Boraginaceae) on Tenerife, Canary islands.

    Science.gov (United States)

    Sedlacek, Janosch; Schmid, Bernhard; Matthies, Diethart; Albrecht, Matthias

    2012-01-01

    How climate-change induced environmental stress may alter the effects of inbreeding in patchy populations of rare species is poorly understood. We investigated the fitness of progeny from experimental self- and cross-pollinations in eight populations of different size of Echium wildpretii, a rare endemic plant of the arid subalpine zone of the Canarian island of Tenerife. As control treatments we used open pollination and autonomous selfing. The seed set of open-pollinated flowers was 55% higher than that of autonomously selfed flowers, showing the importance of animal pollination for reproductive success. The seed set, seed mass and germination rate of seedlings of hand-selfed flowers was similar to that of hand-crossed flowers, indicating weak inbreeding depression (seed set -4.4%, seed mass -4.1%, germination -7.3%). Similarly, under normal watering there were no significant effects of inbreeding on seedling survival (-3.0%). However, under low watering of seedlings inbreeding depression was high (survival -50.2%). Seed set of open- and hand-outcrossed-pollinated flowers was higher in large than in small populations, possibly due to more frequent biparental inbreeding in the latter. However, later measures of progeny fitness were not significantly influenced by population size. We predict that increasing drought duration and frequency due to climate change and reductions of population sizes may increase inbreeding depression in this charismatic plant species and thus threaten its future survival in the longer term.

  7. The effects of inbreeding on sperm quality traits in captive‐bred lake trout, Salvelinus namaycush (Walbaum, 1972)

    DEFF Research Database (Denmark)

    Johnson, K.; Butts, I. A. E.; Smith, J. L.

    2015-01-01

    depression in the studied population, due to purging, low levels of inbreeding or lack of detection at the gametic level, or (ii) relaxed selective pressures due to benign hatchery conditions. The present study provides significant insight into the effects of inbreeding on sperm quality in a captive...

  8. No inbreeding depression in sperm storage ability or offspring viability in Drosophila melanogaster females.

    Science.gov (United States)

    Ala-Honkola, Outi; Manier, Mollie K; Lüpold, Stefan; Droge-Young, Elizabeth M; Collins, William F; Belote, John M; Pitnick, Scott

    2014-01-01

    Mating between relatives usually decreases genetic quality of progeny as deleterious recessive alleles are expressed in inbred individuals. Inbreeding degrades sperm traits but its effects on sperm storage and fate within females are currently unknown. We quantified the relationship between the degrees of inbreeding relevant to natural populations (f=0, 0.25 and 0.50) and the number of sperm inseminated and stored, sperm swimming speed, long-term sperm viability while in storage, pattern of sperm precedence, mating latency, and offspring viability of female Drosophila melanogaster. The use of transgenic flies that have either red or green fluorescent sperm heads allowed us to distinguish two ejaculates in the female reproductive tract and facilitated quantification of sperm storage and use traits. We found no inbreeding depression in either long- or short-term sperm storage ability. The most inbred females exhibited significantly longer mating latency, which could be explained by males preferring to mate with outbred females. On the other hand, as no evidence for cryptic male choice in the form of ejaculate tailoring of sperm number was found, the most inbred females might just be less eager to mate. We also found no evidence that the degree of maternal inbreeding influenced offspring viability. Comparison with a contemporaneous study of male inbreeding consequences for ejaculate quality suggests that inbreeding depression is more severe in males than in females in our study population.

  9. Inbreeding depression of sperm traits in the zebra finch Taeniopygia guttata.

    Science.gov (United States)

    Opatová, Pavlína; Ihle, Malika; Albrechtová, Jana; Tomášek, Oldřich; Kempenaers, Bart; Forstmeier, Wolfgang; Albrecht, Tomáš

    2016-01-01

    Inbreeding depression, or the reduction in fitness due to mating between close relatives, is a key issue in biology today. Inbreeding negatively affects many fitness-related traits, including survival and reproductive success. Despite this, very few studies have quantified the effects of inbreeding on vertebrate gamete traits under controlled breeding conditions using a full-sib mating approach. Here, we provide comprehensive evidence for the negative effect of inbreeding on sperm traits in a bird, the zebra finch Taeniopygia guttata. We compared sperm characteristics of both inbred (pedigree F = 0.25) and outbred (pedigree F = 0) individuals from two captive populations, one domesticated and one recently wild-derived, raised under standardized conditions. As normal spermatozoa morphology did not differ consistently between inbred and outbred individuals, our study confirms the hypothesis that sperm morphology is not particularly susceptible to inbreeding depression. Inbreeding did, however, lead to significantly lower sperm motility and a substantially higher percentage of abnormal spermatozoa in ejaculate. These results were consistent across both study populations, confirming the generality and reliability of our findings.

  10. Estimates of inbreeding depression in the South African Jersey ...

    African Journals Online (AJOL)

    ARC-IRENE

    Estimates of genetic parameters and effect of inbreeding on milk yield and composition ... REML algorithm was used to obtain estimates of the variance components, ratios and empirical best linear .... The matrix representation of the model is as follows: e ... where is the solution vector for fixed effects, is a vector of contrasts,.

  11. Pedigree analysis and inbreeding depression on growth traits in Brazilian Marchigiana and Bonsmara breeds.

    Science.gov (United States)

    Santana, M L; Oliveira, P S; Eler, J P; Gutiérrez, J P; Ferraz, J B S

    2012-01-01

    The study of population structure by pedigree analysis is useful to identify important circumstances that affect the genetic history of populations. The intensive use of a small number of superior individuals may reduce the genetic diversity of populations. This situation is very common for the beef cattle breeds. Therefore, the objectives of the present study were to analyze the pedigree and possible inbreeding depression on traits of economic interest in the Marchigiana and Bonsmara breeds and to test the inclusion of the individual inbreeding coefficient (F(i)) or individual increases in inbreeding coefficient (ΔF(i)) in the genetic evaluation model for the quantification of inbreeding depression. The complete pedigree file of the Marchigiana breed included 29,411 animals born between 1950 and 2003. For the Bonsmara breed, the pedigree file included 18,695 animals born between 1988 and 2006. Only animals with at least 2 equivalent generations of known pedigree were kept in the analyses of inbreeding effect on birth weight, weaning weight measured at about 205 d, and BW at 14 mo in the Marchigiana breed, and on birth weight, weaning weight, and scrotal circumference measured at 12 mo in the Bonsmara breed. The degree of pedigree knowledge was greater for Marchigiana than for Bonsmara animals. The average generation interval was 7.02 and 3.19 for the Marchigiana and Bonsmara breed, respectively. The average inbreeding coefficient was 1.33% for Marchigiana and 0.26% for Bonsmara. The number of ancestors explaining 50% of the gene pool and effective population size computed via individual increase in coancestry were 13 and 97.79 for Marchigiana and 41 and 54.57 for Bonsmara, respectively. These estimates indicate reduction in genetic variability in both breeds. Inbreeding depression was observed for most of the growth traits. The model including ΔF(i) can be considered more adequate to quantify inbreeding depression. The inclusion of F(i) or ΔF(i) in the genetic

  12. Slow inbred lines of Drosophila melanogaster express as much inbreeding depression as fast inbred lines under semi-natural conditions

    DEFF Research Database (Denmark)

    Kristensen, Torsten Nygård; Knudsen, Morten Ravn; Loeschcke, Volker

    2011-01-01

    Selection may reduce the deleterious consequences of inbreeding. This may be due to purging of recessive deleterious alleles or balancing selection favouring heterozygote offspring. Such selection is expected to be more efficient at slower compared to at faster rates of inbreeding. In this study ...

  13. Slow inbred lines of Drosophila melanogaster express as much inbreeding depression as fast inbred lines under semi-natural conditions

    DEFF Research Database (Denmark)

    Kristensen, Torsten Nygård; Knudsen, Morten Ravn; Loeschcke, Volker

    2011-01-01

    Selection may reduce the deleterious consequences of inbreeding. This may be due to purging of recessive deleterious alleles or balancing selection favouring heterozygote offspring. Such selection is expected to be more efficient at slower compared to at faster rates of inbreeding. In this study ...

  14. Feral Pigeons (Columba livia) Prefer Genetically Similar Mates despite Inbreeding Depression.

    Science.gov (United States)

    Jacob, Gwenaël; Prévot, Anne-Caroline; Baudry, Emmanuelle

    2016-01-01

    Avoidance of mating between related individuals is usually considered adaptive because it decreases the probability of inbreeding depression in offspring. However, mating between related partners can be adaptive if outbreeding depression is stronger than inbreeding depression or if females gain inclusive fitness benefits by mating with close kin. In the present study, we used microsatellite data to infer the parentage of juveniles born in a French colony of feral pigeons, which allowed us to deduce parent pairs. Despite detectable inbreeding depression, we found that pairwise relatedness between mates was significantly higher than between nonmates, with a mean coefficient of relatedness between mates of 0.065, approximately half the theoretical value for first cousins. This higher relatedness between mates cannot be explained by spatial genetic structure in this colonial bird; it therefore probably results from an active choice. As inbreeding but not outbreeding depression is observed in the study population, this finding accords with the idea that mating with genetically similar mates can confer a benefit in terms of inclusive fitness. Our results and published evidence suggest that preference for related individuals as mates might be relatively frequent in birds.

  15. Experimental and genetic analyses reveal that inbreeding depression declines with increased self-fertilization among populations of a coastal dune plant.

    Science.gov (United States)

    Dart, S; Eckert, C G

    2013-03-01

    Theory predicts that inbreeding depression (ID) should decline via purging in self-fertilizing populations. Yet, intraspecific comparisons between selfing and outcrossing populations are few and provide only mixed support for this key evolutionary process. We estimated ID for large-flowered (LF), predominantly outcrossing vs. small-flowered (SF), predominantly selfing populations of the dune endemic Camissoniopsis cheiranthifolia by comparing selfed and crossed progeny in glasshouse environments differing in soil moisture, and by comparing allozyme-based estimates of the proportion of seeds selfed and inbreeding coefficient of mature plants. Based on lifetime measures of dry mass and flower production, ID was stronger in nine LF populations [mean δ = 1-(fitness of selfed seed/fitness of outcrossed seed) = 0.39] than 16 SF populations (mean δ = 0.03). However, predispersal ID during seed maturation was not stronger for LF populations, and ID was not more pronounced under simulated drought, a pervasive stress in sand dune habitat. Genetic estimates of δ were also higher for four LF (δ = 1.23) than five SF (δ = 0.66) populations; however, broad confidence intervals around these estimates overlapped. These results are consistent with purging, but selective interference among loci may be required to maintain strong ID in partially selfing LF populations, and trade-offs between selfed and outcrossed fitness are likely required to maintain outcrossing in SF populations.

  16. Assessment of inbreeding depression for functional herd life in the ...

    African Journals Online (AJOL)

    p2492989

    P-value b F ± SE. P-value. 1. -0.0010 ± 0.0005**. 0.0455. -0.1874 ± 0.1995. 0.3472. 2 ... the individual inbreeding of animals in the population, accounting for the amount of known pedigree ... This property is an advantage of ∆Fi over Fi when pedigree is incomplete. The .... Van Wyk, J.B., Fair, M.D. & Cloete, S.W.P., 2009.

  17. Genetic Parameters and Inbreeding Depression of Litter Weight in Pannon White Rabbits

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    István Nagy

    2011-09-01

    Full Text Available Genetic parameters and inbreeding depression were estimated for litter weight at day 21 of a synthetic Pannon White rabbit population selected as a closed population since 1992. The data file consisted of 15652 kindling records of 3711 rabbit does (mated to 933 bucks collected between 1992 and 2009. The total number of animals in the pedigree file was 4804. REML and BLUP procedures were applied using repeatability animal model (VCE and PEST soft ware. The estimated narrow sense heritability for litter weight was low (0.08±0.01. The estimated permanent environmental effects showed higher relative importance compared to the additive genetic effects (0.13±0.01. Analyzing the inbreeding depression simultaneously for all parities, increasing the inbreeding coefficient by 10% had small positive effect on litter weight (0.028 kg but the estimate was not significant (p=0.30. When the inbreeding depression was estimated by parities small depressions (-0.023, -0.045 and -0.021 kg were found for the 2-4th parity groups but the estimates were not significant (p=0.59, 0.23 and 0.61, respectively. On the contrary a significant positive effect was observed for the 1st parity (0.198 kg; p=0.01. The small positive estimate estimated at the 5th parity (0.033 kg was not significant (p=0.39.

  18. Genetic Parameters and Inbreeding Depression of Litter Weight in Pannon White Rabbits

    Directory of Open Access Journals (Sweden)

    István Nagy

    2011-10-01

    Full Text Available Genetic parameters and inbreeding depression were estimated for litter weight at day 21 of a synthetic Pannon White rabbit population selected as a closed population since 1992. The data file consisted of 15652 kindling records of 3711 rabbit does (mated to 933 bucks collected between 1992 and 2009. The total number of animals in the pedigree file was 4804. REML and BLUP procedures were applied using repeatability animal model (VCE and PEST soft ware. The estimated narrow sense heritability for litter weight was low (0.08±0.01. The estimated permanent environmental effects showed higher relative importance compared to the additive genetic effects (0.13±0.01. Analyzing the inbreeding depression simultaneously for all parities, increasing the inbreeding coefficient by 10% had small positive effect on litter weight (0.028 kg but the estimate was not significant (p=0.30. When the inbreeding depression was estimated by parities small depressions (-0.023, -0.045 and -0.021 kg were found for the 2-4th parity groups but the estimates were not significant (p=0.59, 0.23 and 0.61, respectively. On the contrary a significant positive effect was observed for the 1st parity (0.198 kg; p=0.01. The small positive estimate estimated at the 5th parity (0.033 kg was not significant (p=0.39.

  19. A new theory for the evolution of polyandry as a means of inbreeding avoidance.

    Science.gov (United States)

    Cornell, Stephen J; Tregenza, Tom

    2007-11-22

    We propose a novel theory for the evolution of polyandry driven by genetic benefits to females whose offspring interbreed. In species with an ecology characterized by frequent colonization of new habitat patches, consanguineous matings may be common during the early stages of colonization, but genetic diversity may grow as new colonizers arrive. We show that with levels of inbreeding depression similar to those found in predominantly inbreeding populations, a polyandrous female can benefit her descendants since matings among her brood are mainly between half siblings rather than full siblings. We examine the invasion by a polyandrous phenotype using explicit genetic models in which costs of inbreeding are themselves subject to selection. In common with other models of inbreeding, we find that underlying high levels of inbreeding tend to purge deleterious recessive alleles, and hence these are unlikely to maintain sufficient inbreeding depression to favour polyandry. However, if costs of inbreeding are due to overdominance, biologically realistic levels of inbreeding depression result in genetic benefits large enough to favour polyandry provided it is not too costly. The potential significance of polyandry as a mechanism to reduce inbreeding in grandchildren will depend upon the genetic basis of inbreeding depression in natural, inbreeding populations.

  20. Calving Performance in the Endangered Murboden Cattle Breed: Genetic Parameters and Inbreeding Depression

    Directory of Open Access Journals (Sweden)

    Sophie A.e. Eaglen

    2013-09-01

    Full Text Available Calving is a key event on any cattle farm, with both economic and animal welfare consequences when complications arise. Although mostly reported in highly selected breeds, problematic calving performance is also a worry to the unselected dualpurpose Murboden breed, local to Austria. This study presents genetic parameter estimates for calving ease and stillbirth in Murboden cattle. Furthermore, a potential effect of inbreeding on the breeds’ calving performance is evaluated. Results show a moderate direct and maternal heritability (0.18±0.04; 0.11±0.02 and a significant negative direct-maternal genetic correlation for calving ease (-0.41±0.10. Heritabilities of stillbirth are low yet significant (0.048±0.01; 0.018±0.007. A significant effect of inbreeding was detected on maternal calving ease i.e. the ease with which a dam calves. By categorizing the inbreeding coefficients of the dam in six ascending classes it was shown that calving ease worsens as inbreeding coefficients become larger. Results of this study reveal significant genetic variation in calving performance of the Murboden breed which opens doors for genetic selection. An additional important aspect of this study is that its result on inbreeding depression gives counterweight to the general intuitive notion in literature that high selection for production traits is the major contributor to calving difficulty in dairy and beef cattle breeds worldwide.

  1. Morphological traits and inbreeding depression in Bracco Italiano dog breed

    Directory of Open Access Journals (Sweden)

    Francesca Cecchi

    2015-07-01

    Full Text Available This paper reports the first results of a survey on morphological traits in Bracco Italiano dog breed, and analyzes the effects of various levels of inbreeding on these measures. Traits were taken from 155 adult (mean age 4.18±2.60 years dogs (79 males and 76 females belonging to 57 different farms. For each animal, the following biometrical measurements were considered: height at withers (WH, height of chest (ChH, body length (BL, length at rump (RL, height at rump (RH, iliac width of rump (RIlW, ischiatic width of rump (RIsW, circumference of chest (ChC, circumference of cannon (CaC, length of ear (EL, and length of head (HL. The ratio of rump length/withers height (RL/WH, cannon circumference/chest circumference (CaC/ChC and head length/withers height (HL/WH were also calculated. ANOVA was used to test the differences between males and females and among farms in terms of morphological measurements and ratios. Significant differences between males and females were observed for many morphological traits. The measures coincided with what reported in the current breed standard, apart from the length of the rump, which was around ¼ of the withers height rather than the 1/3 required in the standard. No significant effect of inbreeding on conformation traits was observed.

  2. Inbreeding and purging at the genomic Level: the Chillingham cattle reveal extensive, non-random SNP heterozygosity.

    Science.gov (United States)

    Williams, J L; Hall, S J G; Del Corvo, M; Ballingall, K T; Colli, L; Ajmone Marsan, P; Biscarini, F

    2016-02-01

    Local breeds of livestock are of conservation significance as components of global biodiversity and as reservoirs of genetic variation relevant to the future sustainability of agriculture. One such rare historic breed, the Chillingham cattle of northern England, has a 350-year history of isolation and inbreeding yet shows no diminution of viability or fertility. The Chillingham cattle have not been subjected to selective breeding. It has been suggested previously that the herd has minimal genetic variation. In this study, high-density SNP genotyping with the 777K SNP chip showed that 9.1% of loci on the chip are polymorphic in the herd, compared with 62-90% seen in commercial cattle breeds. Instead of being homogeneously distributed along the genome, these loci are clustered at specific chromosomal locations. A high proportion of the Chillingham individuals examined were heterozygous at many of these polymorphic loci, suggesting that some loci are under balancing selection. Some of these frequently heterozygous loci have been implicated as sites of recessive lethal mutations in cattle. Linkage disequilibrium equal or close to 100% was found to span up to 1350 kb, and LD was above r(2) = 0.25 up to more than 5000 kb. This strong LD is consistent with the lack of polymorphic loci in the herd. The heterozygous regions in the Chillingham cattle may be the locations of genes relevant to fitness or survival, which may help elucidate the biology of local adaptation in traditional breeds and facilitate selection for such traits in commercial cattle.

  3. Estimating the inbreeding depression on cognitive behavior: a population based study of child cohort.

    Directory of Open Access Journals (Sweden)

    Mohd Fareed

    Full Text Available BACKGROUND: Cognitive ability tests are widely assumed to measure maximal intellectual performance and predictive associations between intelligence quotient (IQ scores and later mental health problems. Very few epidemiologic studies have been done to demonstrate the relationship between familial inbreeding and modest cognitive impairments in children. OBJECTIVE: We aimed to estimate the effect of inbreeding on children's cognitive behavior in comparison with non-inbred children. METHODOLOGY: A cohort of 408 children (6 to 15 years of age was selected from inbred and non-inbred families of five Muslim populations of Jammu region. The Wechsler Intelligence Scales for Children (WISC was used to measure the verbal IQ (VIQ, performance IQ (PIQ and full scale IQ (FSIQ. Family pedigrees were drawn to access the family history and children's inbred status in terms of coefficient of inbreeding (F. RESULTS: We found significant decline in child cognitive abilities due to inbreeding and high frequency of mental retardation among offspring from inbred families. The mean differences (95% C.I. were reported for the VIQ, being -22.00 (-24.82, -19.17, PIQ -26.92 (-29.96, -23.87 and FSIQ -24.47 (-27.35,-21.59 for inbred as compared to non-inbred children (p<0.001 [corrected].The higher risk of being mentally retarded was found to be more obvious among inbred categories corresponding to the degree of inbreeding and the same accounts least for non-inbred children (p<0.0001. We observed an increase in the difference in mean values for VIQ, PIQ and FSIQ with the increase of inbreeding coefficient and these were found to be statistically significant (p<0.05. The regression analysis showed a fitness decline (depression for VIQ (R2 = 0.436, PIQ (R2 = 0.468 and FSIQ (R2 = 0.464 with increasing inbreeding coefficients (p<0.01. CONCLUSIONS: Our comprehensive assessment provides the evidence for inbreeding depression on cognitive abilities among children.

  4. Early-acting inbreeding depression and reproductive success in the highbush blueberry, Vaccinium corymbosum L.

    Science.gov (United States)

    Krebs, S L; Hancock, J F

    1990-06-01

    Tetraploid Vaccinium corymbosum genotypes exhibit wide variability in seed set following self- and cross-pollinations. In this paper, a post-zygotic mechanism (seed abortion) under polygenic control is proposed as the basis for fertility differences in this species. A pollen chase experiment indicated that self-pollen tubes fertilize ovules, but are also 'outcompeted' by foreign male gametes in pollen mixtures. Matings among cultivars derived from a pedigree showed a linear decrease in seed number per fruit, and increase in seed abortion, with increasing relatedness among parents. Selfed (S1) progeny from self-fertile parents were largely self-sterile. At zygotic levels of inbreeding of F>0.3 there was little or no fertility, suggesting that an inbreeding threshold regulates reproductive success in V. corymbosum matings. Individuals below the threshold are facultative selfers, while those above it are obligate outcrossers. Inbreeding also caused a decrease in pollen viability, and reduced female fertility more rapidly than male fertility. These phenomena are discussed in terms of two models of genetic load: (1) mutational load - homozygosity for recessive embryolethal or sub-lethal mutations and (2) segregational load - loss of allelic interactions essential for embryonic vigor. Self-infertility in highbush blueberries is placed in the context of 'late-acting' self-incompatibility versus 'early-acting' inbreeding depression in angiosperms.

  5. On the Consequences of Purging and Linkage on Fitness and Genetic Diversity

    Directory of Open Access Journals (Sweden)

    Diego Bersabé

    2016-01-01

    Full Text Available Using computer simulation we explore the consequences of linkage on the inbreeding load of an equilibrium population, and on the efficiency of purging and the loss of genetic diversity after a reduction in population size. We find that linkage tends to cause increased inbreeding load due to the build up of coupling groups of (partially recessive deleterious alleles. It also induces associative overdominance at neutral sites but rarely causes increased neutral genetic diversity in equilibrium populations. After a reduction in population size, linkage can cause some delay both for the expression of the inbreeding load and the corresponding purging. However, reasonable predictions can be obtained for the evolution of fitness under inbreeding and purging by using empirical estimates of the inbreeding depression rate. Purging selection against homozygotes for deleterious alleles affects the population’s pedigree. Furthermore, it can slow the loss of genetic diversity compared to that expected from the variance of gametic contributions to the breeding group and even from pedigree inbreeding. Under some conditions, this can lead to a smaller loss of genetic diversity, even below that expected from population size in the absence of selection.

  6. How much gene flow is needed to avoid inbreeding depression in wild tiger populations?

    Science.gov (United States)

    Kenney, John; Allendorf, Fred W; McDougal, Charles; Smith, James L D

    2014-08-22

    The number and size of tiger populations continue to decline owing to habitat loss, habitat fragmentation and poaching of tigers and their prey. As a result, tiger populations have become small and highly structured. Current populations have been isolated since the early 1970s or for approximately seven generations. The objective of this study is to explore how inbreeding may be affecting the persistence of remaining tiger populations and how dispersal, either natural or artificial, may reduce the potentially detrimental effect of inbreeding depression. We developed a tiger simulation model and used published levels of genetic load in mammals to simulate inbreeding depression. Following a 50 year period of population isolation, we introduced one to four dispersing male tigers per generation to explore how gene flow from nearby populations may reduce the negative impact of inbreeding depression. For the smallest populations, even four dispersing male tigers per generation did not increase population viability, and the likelihood of extinction is more than 90% within 30 years. Unless habitat connectivity is restored or animals are artificially introduced in the next 70 years, medium size wild populations are also likely to go extinct, with only four to five of the largest wild tiger populations likely to remain extant in this same period without intervention. To reduce the risk of local extinction, habitat connectivity must be pursued concurrently with efforts to increase population size (e.g. enhance habitat quality, increase habitat availability). It is critical that infrastructure development, dam construction and other similar projects are planned appropriately so that they do not erode the extent or quality of habitat for these populations so that they can truly serve as future source populations. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  7. Depression by inbreeding after four sucessive self-pollination squash generations

    Directory of Open Access Journals (Sweden)

    Cardoso Antonio Ismael Inácio

    2004-01-01

    Full Text Available The strategy for breeding F1 hybrid squash is to develop parental lines through self-pollination. However, it increases plant mean homozygosis, which is not the natural genetic state of a cross-pollinated species, and can cause "inbreeding depression". The objective of this work was to evaluate this depression with sucessive generations of self-pollination (without selection in Cucurbita moschata, cv. Piramoita. Populations were obtained from lines with one to four generations of self-pollination (obtained by the SSD method, from the original cv. Piramoita (population S0. Randomized blocks were used with five treatments (different generations of self-pollination - S0 to S4, six replicates and five plants per plot. Regression analysis was made by the Wright inbreeding coefficient (F to measure the homozygosis level effect on vigor loss. There was a linear reduction of mean weight and fruit length, seed production (number and weight per fruit with the increase of the homozygosis level; however inbreeding did not affect seed quality (weight of 100 seeds and germination.

  8. Evidence for inbreeding depression in the food-deceptive colour-dimorphic orchid Dactylorhiza sambucina (L.) Soò.

    Science.gov (United States)

    Juillet, N; Dunand-Martin, S; Gigord, L D B

    2007-01-01

    About one third of all orchid species are deceptive, i.e., not providing any reward to their pollinator. Such species often have lower visitation rates compared to rewarding relatives. This could result in lower levels of geitonogamous selfing and thus would provide an advantage in term of progeny fitness through inbreeding avoidance. This hypothesis could be tested by comparing the level of inbreeding depression between deceptive and rewarding orchids. However, due to the difficulty to raise orchids from seeds, few studies of inbreeding depression are available, and most are focused on very early life stages, such as seed mass or embryo viability. Here, we present the results from an experimental investigation of inbreeding depression in the deceptive flower-colour dimorphic Dactylorhiza sambucina, from in vitro cultivation to greenhouse soil transplantation. We found strong inbreeding depression at all recorded stages (i.e., germination and survival), with estimates ranging from 0.47 to 0.75. Our study finally proposes a simple and suitable experimental protocol to raise orchids from seeds with high germination rates.

  9. Inbreeding depression on growth and survival of full-sib family of Manila clam ( Ruditapes philippinarum)

    Science.gov (United States)

    Huo, Zhongming; Li, Na; Zhang, Xuekai; Li, Ying; Yan, Xiwu; Yang, Feng

    2017-02-01

    In present study, the inbreeding depression ( ID) of growth and survival of Manila clam (Ruditapes philippinarum) was investigated at larval and juvenile stages. Nine inbred families ( A 2, B 2, C 2, D 2, E 2, F 2, G 2, H 2 and I 2) were established by mating within nine full-sib families with expected inbreeding coefficient of 0.25. Inbred families showed significant differences in shell length and hatching rate of D-larvae (straight-hinged larvae). The larvae of the nine inbred families grew slower than those of control group ( CG), and their ID value ranged from 0.81% ± 6.09% to 16.10% ± 1.49%. The ID value of larval survival rate varied between 27.47% ± 9.36% and 70.50% ± 13.66%. The ID was also detected for juvenile growth in A 2, B 2, C 2, and D 2, which ranged from 4.60 ± 2.21 to 17.71 ± 7.73. The A 2 family maintained the highest juvenile survival rate, whereas the other inbred families exhibited ID values varying between 62.79% ± 4.54% and 96.14% ± 0.87%. The linear relationship of estimated ID between growth and survival was negatively correlated ( R = -0.434, P < 0.05). The results of this study suggested that the ID of growth was common at the larval stage but was less prevalent at juvenile stage. In contrast, the ID of survival increased from larval to juvenile stage. A better understanding of the effect of inbreeding may aid to selective breeding of Manila clam.

  10. Rapid decrease in horn size of bighorn sheep: environmental decline, inbreeding depression, or evolutionary response to trophy hunting?

    Science.gov (United States)

    Hedrick, Philip W

    2011-01-01

    There are numerous examples demonstrating that selection has greatly influenced phenotypes in wild-harvested species. Here, a significant reduction in horn size in trophy desert bighorn sheep rams over 30 years in a reintroduced population in Aravaipa Canyon, Arizona is documented. After examining the potential effects of a detrimental change in the environment, inbreeding depression, and hunter-caused evolutionary change, it appears that environmental deterioration, apparently from the effects of drought, may be a major cause of the decline in horn size. In particular, the reduction in ram horn size is positively associated with reduced winter lifetime rainfall over the 3 decades. Over the same period, the demographic indicator lamb-to-ewe ratio has also declined in the Aravaipa population. On the other hand, lamb-to-ewe ratio has not declined statewide in Arizona, and the population size in Aravaipa appears to be increasing, suggesting local- and trait-specific effects. Using a theoretical context, neither inbreeding depression nor hunter selection by themselves appear to the sole causes of the lower horn size. However, some combination of environmental factors, inbreeding depression, and hunter selection may have caused the decrease in observed horn size. It is not clear what management actions might be successful in countering the environmental effects on horn size, but supplemental feeding and cattle removal are suggested while translocation is suggested to counter the effects of inbreeding depression and reduced hunting and translocation are suggested to counter the effects of hunter selection.

  11. Assessment of inbreeding depression in Nellore cows (Bos indicus) through high-density SNP genotypes

    Science.gov (United States)

    Inbreeding has been incriminated as a cause of decrease in reproductive performance in cattle. This negative correlation is known as ‘inbreeding depression’, and evidence supporting this hypothesis was generated from association studies between reproductive traits and estimates of inbreeding coeffic...

  12. Strong inbreeding depression and individually variable mating system in the narrow endemic Erodium cazorlanum (Geraniaceae

    Directory of Open Access Journals (Sweden)

    Alonso, Conchita

    2013-06-01

    Full Text Available Angiosperms evolved different systems to attract effective pollinators while reducing selfing in hermaphroditic flowers. Selfing ability can be advantageous when pollinators and/or mates are scarce, although inbreeding depression may largely reduce those advantages. Recent comparative analyses suggested endemic species tend to evolve self-compatibility but a better understanding of the associated reproductive and genetic tradeoffs is required. Experimental hand-pollinations under greenhouse conditions were conducted to investigate the selfing ability and estimate inbreeding depression up to the offspring’ first reproductive event in Ero dium cazorlanum, a narrow endemic species restricted to dolomite outcrops in SE Spanish mountains. We found autonomous selfing ineffective. Further, when experimentally applied, pollen of the same flower produced significantly fewer fruits and seeds compared to geitonogamous and cross pollinations. The number of seeds per fruit was significantly higher after cross pollinations and strong inbreeding depression accumulated through the life-cycle. Interestingly, individual plants exhibited broad variation in selfing ability with six out of 14 individuals producing no seed after geitonogamy. Understanding the consequences of individual variation in self compatibility deserves further investigation in the field now that we know that strong inbreeding depression may limit recruitment of selfed progeny.Las Angiospermas han desarrollado diversos sistemas para atraer polinizadores eficientes y al mismo tiempo reducir la posibilidad de autopolinización asociada al hermafroditismo. La capacidad de autopolinización puede ser ventajosa en situaciones de escasez de polinizadores y/o individuos reproductores, beneficios que pueden reducirse ampliamente a causa de la depresión por endogamia. Análisis filogenéticos recientes indicaron que las especies endémicas tienden a presentar sistemas de autocompatibilidad, por tanto

  13. Fitness drivers in the threatened Dianthus guliae Janka (Caryophyllaceae): disentangling effects of growth context, maternal influence and inbreeding depression.

    Science.gov (United States)

    Gargano, D; Gullo, T; Bernardo, L

    2011-01-01

    We studied inbreeding depression, growth context and maternal influence as constraints to fitness in the self-compatible, protandrous Dianthus guliae Janka, a threatened Italian endemic. We performed hand-pollinations to verify outcomes of self- and cross-fertilisation over two generations, and grew inbred and outbred D. guliae offspring under different conditions - in pots, a common garden and field conditions (with/without nutrient addition). The environment influenced juvenile growth and flowering likelihood/rate, but had little effect on inbreeding depression. Significant interactions among genetic and environmental factors influenced female fertility. Overall, genetic factors strongly affected both early (seed mass, seed germination, early survival) and late (seed/ovule ratio) life-history traits. After the first pollination experiment, we detected higher mortality in the selfed progeny, which is possibly a consequence of inbreeding depression caused by over-expression of early-acting deleterious alleles. The second pollination induced a strong loss of reproductive fitness (seed production, seed mass) in inbred D. guliae offspring, regardless of the pollination treatment (selfing/crossing); hence, a strong (genetic) maternal influence constrained early life-history traits of the second generation. Based on current knowledge, we conclude that self-compatibility does not prevent the detrimental effects of inbreeding in D. guliae populations, and may increase the severe extinction risk if out-crossing rates decrease.

  14. The contribution of dominance and inbreeding depression in estimating variance components for litter size in Pannon White rabbits.

    Science.gov (United States)

    Nagy, I; Gorjanc, G; Curik, I; Farkas, J; Kiszlinger, H; Szendrő, Zs

    2013-08-01

    In a synthetic closed population of Pannon White rabbits, additive (VA ), dominance (VD ) and permanent environmental (VPe ) variance components as well as doe (bF d ) and litter (bF l ) inbreeding depression were estimated for the number of kits born alive (NBA), number of kits born dead (NBD) and total number of kits born (TNB). The data set consisted of 18,398 kindling records of 3883 does collected from 1992 to 2009. Six models were used to estimate dominance and inbreeding effects. The most complete model estimated VA and VD to contribute 5.5 ± 1.1% and 4.8 ± 2.4%, respectively, to total phenotypic variance (VP ) for NBA; the corresponding values for NBD were 1.9 ± 0.6% and 5.3 ± 2.4%, for TNB, 6.2 ± 1.0% and 8.1 ± 3.2% respectively. These results indicate the presence of considerable VD . Including dominance in the model generally reduced VA and VPe estimates, and had only a very small effect on inbreeding depression estimates. Including inbreeding covariates did not affect estimates of any variance component. A 10% increase in doe inbreeding significantly increased NBD (bF d  = 0.18 ± 0.07), while a 10% increase in litter inbreeding significantly reduced NBA (bF l  = -0.41 ± 0.11) and TNB (bF l  = -0.34 ± 0.10). These findings argue for including dominance effects in models of litter size traits in populations that exhibit significant dominance relationships. © 2012 Blackwell Verlag GmbH.

  15. The Quadraplex Tetraploids Hybrids and Duplex Tetraploids Hybrids Are Responsible for Heterosis and Inbreeding Depression in Maize

    Institute of Scientific and Technical Information of China (English)

    WANG Ze-li; James A Birchler; WANG Lu-xin; JIN Liang

    2005-01-01

    The maize quadraplex tetraploids and duplex tetraploids were developed using Kato's protocols. The phenotype of heterosis and inbreeding depression over generations in their parents and progenies of F1, F2 and F3 were investigated.The results indicated that different duplex tetraploids have different genetic backgrounds, but they acquire maximum heterosis at same traits, such as the leaf length, leaf width, culm circumference and days to flowering. P.N. rises much faster from the F2 to F3 segment than the A.W. does for the plant height in duplex tetraploids. In comparing duplex and quadraplex over a generation the quadriplex is showing the greatest heterosis in plant height, leaf height, leaf width and days to flowering. Most of the examples achieve the maximum heterosis at Qu F2, with the exception of culm circumference,which achieves greatest heterosis at PNAW F1. Meanwhile, this experiment shows that quadraplex tetraploids has distinct additional favorable alleles that are not contained in duplex tetraploid, this is demonstrated by the heterosis found in crosses between the two duplex tetraploid. This finding helps explain quadraploids superiority and unique breeding behavior, in which, the progressive heterosis and inbreeding depression in maize are due mainly to linkage disequilibrium.The severe inbreeding depression in duplex tetraploids is due mainly to the rapid loss of complementary chromosomes or genes interactions in the first few generation of inbreeding. Correspondingly, the progressive heterosis in quadraplex tetraploids is due mainly to a progressive increase in complementarities of homologous chromosomes or genes interactions.Greater complementarities of homologous chromosomes or genes interactions in tetraploids maize alse helps explain recent molecular biology research indicating that some of traits in quadraplex tetraploids are more responsive to genetic diversity than in duplex tetraploids. In addition, the dosage effect of polyploid in relation

  16. Depressão por endogamia em populações de milho-pipoca Inbreeding depression in popcorn populations

    Directory of Open Access Journals (Sweden)

    Gustavo André Simon

    2004-01-01

    Full Text Available Oito populações de milho-pipoca (CMS-42, CMS-43, Zélia, RS-20, Catedral, Zaeli, UEM-J1 e UEM-M2 foram avaliadas com o objetivo de obter estimativas de depressão por endogamia, componentes genéticos de média e comparar essas estimativas por grupos de populações. O delineamento experimental utilizado foi o de blocos ao acaso em esquema de parcelas subdivididas, cujos tratamentos primários foram os níveis de endogamia (S1 e S0 e os tratamentos secundários, as populações, com três repetições, em dois anos agrícolas (1998/99 e 1999/00. Foram avaliadas várias características, com ênfase no rendimento de grãos (RG e na capacidade de expansão (CE. O método de GARDNER (1965 foi empregado para obter as estimativas dos componentes genéticos de médias. Observaram-se menores valores de depressão por endogamia e predominância de efeitos gênicos aditivos para CE em relação ao RG. A depressão endogâmica para rendimento de grãos foi maior no grupo dos compostos em relação às populações não melhoradas e à população melhorada. A probabilidade de sucesso na obtenção de linhagens vigorosas e de alta capacidade de expansão é baixa para todas as populações.Eight popcorn populations (CMS-42, CMS-43, Zelia, RS-20, Catedral, Zaeli, UEM-J1 and UEM-M2 were evaluated aiming at obtaintion of estimates of inbreeding depression and average genetic components and to compare these estimates to each genetic group. Each trial was carried out with plots in randomized complete block design with three replications in split-plot experiment, in which the plots were the inbreeding levels (S1 and S0 and in the sub-plots the populations in two years (1998/99 and 1999/00. The characteristics grain yield and popping expansion were evaluated. The GARDNER methodology (1965 was used for obtaining the estimates of average genetic components. It was observed lower values of inbreeding depression and predominance of additive effects for popping

  17. No Inbreeding depression for low temperature developmental acclimation across multiple drosophila species

    DEFF Research Database (Denmark)

    Kristensen, Torsten Nygård; Loeschcke, Volker; Bilde, Trine

    2011-01-01

    is highly species specific, and differs among ecotypes (e.g., tropical and widespread species). Apart from being exposed to thermal stress many small and fragmented populations face genetic challenges due to, for example, inbreeding. Inbreeding has been shown to reduce inherent resistance levels toward......Populations are from time to time exposed to stressful temperatures. Their thermal resistance levels are determined by inherent and plastic mechanisms, which are both likely to be under selection in natural populations. Previous studies on Drosophila species have shown that inherent resistance...... stressful temperatures, but whether adaptation to thermal stress through plastic responses also is affected by inbreeding is so far not clear. In this study, we test inherent cold resistance and the ability to respond plastically to temperature changes through developmental cold acclimation in inbred...

  18. Molecular and quantitative signatures of biparental inbreeding depression in the self-incompatible tree species Prunus avium.

    Science.gov (United States)

    Jolivet, C; Rogge, M; Degen, B

    2013-05-01

    Genetic diversity strongly influences populations' adaptability to changing environments and therefore survival. Sustainable forest management practices have multiple roles including conservation of genetic resources and timber production. In this study, we aimed at better understanding the variation in genetic diversity among adult and offspring individuals, and the effects of mating system on offspring survival and growth in wild cherry, Prunus avium. We analysed adult trees and open pollinated seed-families from three stands in Germany at eight microsatellite loci and one incompatibility system locus and conducted paternity analyses. Seed viability testing and seed sowing in a nursery allowed further testing for the effects of pollen donor diversity and genetic similarity between mates on the offspring performance at the seed and seedling stages. Our results were contrasting across stands. Loss of genetic diversity from adult to seedling stages and positive effect of mate diversity on offspring performance occurred in one stand only, whereas biparental inbreeding depression and significant decrease in fixation index from adults to seedlings was detected in two stands. We discussed the effects of stand genetic diversity on the magnitude of biparental inbreeding depression at several life-stages and its consequences on the management of genetic resources in P. avium.

  19. Genetic variation of inbreeding depression among floral and fitness traits in Silene nutans

    DEFF Research Database (Denmark)

    Thiele, Jan; Hansen, Thomas Møller; Siegismund, Hans Redlef

    2010-01-01

    decoupled. There was a trend that the smaller population was less affected by ID than the large one, although the differences were not significant for most traits. Hence, evidence for purging of deleterious alleles remains inconclusive in this study. Genetic variation in ID among paternal families...

  20. How much gene flow is needed to avoid inbreeding depression in wild tiger populations?

    OpenAIRE

    Kenney, John; Allendorf, Fred W.; McDougal, Charles; Smith, James L. D.

    2014-01-01

    The number and size of tiger populations continue to decline owing to habitat loss, habitat fragmentation and poaching of tigers and their prey. As a result, tiger populations have become small and highly structured. Current populations have been isolated since the early 1970s or for approximately seven generations. The objective of this study is to explore how inbreeding may be affecting the persistence of remaining tiger populations and how dispersal, either natural or artificial, may reduc...

  1. A comparison of pedigree- and DNA-based measures for identifying inbreeding depression in the critically endangered Attwater's Prairie-chicken.

    Science.gov (United States)

    Hammerly, Susan C; Morrow, Michael E; Johnson, Jeff A

    2013-11-01

    The primary goal of captive breeding programmes for endangered species is to prevent extinction, a component of which includes the preservation of genetic diversity and avoidance of inbreeding. This is typically accomplished by minimizing mean kinship in the population, thereby maintaining equal representation of the genetic founders used to initiate the captive population. If errors in the pedigree do exist, such an approach becomes less effective for minimizing inbreeding depression. In this study, both pedigree- and DNA-based methods were used to assess whether inbreeding depression existed in the captive population of the critically endangered Attwater's Prairie-chicken (Tympanuchus cupido attwateri), a subspecies of prairie grouse that has experienced a significant decline in abundance and concurrent reduction in neutral genetic diversity. When examining the captive population for signs of inbreeding, variation in pedigree-based inbreeding coefficients (f(pedigree)) was less than that obtained from DNA-based methods (f(DNA)). Mortality of chicks and adults in captivity were also positively correlated with parental relatedness (r(DNA)) and f(DNA), respectively, while no correlation was observed with pedigree-based measures when controlling for additional variables such as age, breeding facility, gender and captive/release status. Further, individual homozygosity by loci (HL) and parental rDNA values were positively correlated with adult mortality in captivity and the occurrence of a lethal congenital defect in chicks, respectively, suggesting that inbreeding may be a contributing factor increasing the frequency of this condition among Attwater's Prairie-chickens. This study highlights the importance of using DNA-based methods to better inform management decisions when pedigrees are incomplete or errors may exist due to uncertainty in pairings. © 2013 John Wiley & Sons Ltd.

  2. Inbreeding and adaptive plasticity: an experimental analysis on predator-induced responses in the water flea Daphnia.

    Science.gov (United States)

    Swillen, Ine; Vanoverbeke, Joost; De Meester, Luc

    2015-07-01

    Several studies have emphasized that inbreeding depression (ID) is enhanced under stressful conditions. Additionally, one might imagine a loss of adaptively plastic responses which may further contribute to a reduction in fitness under environmental stress. Here, we quantified ID in inbred families of the cyclical parthenogen Daphnia magna in the absence and presence of fish predation risk. We test whether predator stress affects the degree of ID and if inbred families have a reduced capacity to respond to predator stress by adaptive phenotypic plasticity. We obtained two inbred families through clonal selfing within clones isolated from a fish pond. After mild purging under standardized conditions, we compared life history traits and adaptive plasticity between inbred and outbred lineages (directly hatched from the natural dormant egg bank of the same pond). Initial purging of lineages under standardized conditions differed among inbred families and exceeded that in outbreds. The least purged inbred family exhibited strong ID for most life history traits. Predator-induced stress hardly affected the severity of ID, but the degree to which the capacity for adaptive phenotypic plasticity was retained varied strongly among the inbred families. The least purged family overall lacked the capacity for adaptive phenotypic plasticity, whereas the family that suffered only mild purging exhibited a potential for adaptive plasticity that was comparable to the outbred population. We thus found that inbred offspring may retain the capacity to respond to the presence of fish by adaptive phenotypic plasticity, but this strongly depends on the parental clone engaging in selfing.

  3. Purge corruption detection

    Energy Technology Data Exchange (ETDEWEB)

    Nankee, R.J. II; Frantz, D.C.; Tamm, J.R.; Gutermuth, T.R.

    1989-04-18

    This patent describes an adaptive memory cell update method for the detection and correction of a possible purge corruption of the adaptive memory portion of the memory in an internal combustion engine control unit, the adaptive memory portion having purge free cells and normal cells. The method consists of: determining the adaptive memory cells to be used during the adaptive memory cell update by determining if the engine conditions are right to turn the purge system off; if the conditions are right to turn the purge system off, turning the purge system off and using the purge free cells in the adaptive memory cell update; if the conditions are not right to turn the purge system off, turning the purge system on and using the normal cells in the adaptive memory cell update.

  4. The association of genotype-based inbreeding coefficient with a range of physical and psychological human traits

    NARCIS (Netherlands)

    Verweij, K.J.H.; Abdellaoui, A.; Veijola, J.; Sebert, S.; Koiranen, M.; Keller, M.C.; Jarvelin, M.R.; Zietsch, B.P.

    2014-01-01

    Across animal species, offspring of closely related mates exhibit lower fitness, a phenomenon called inbreeding depression. Inbreeding depression in humans is less well understood because mating between close relatives is generally rare and stigmatised, confounding investigation of its effect on

  5. Inbreeding avoidance in spiders: evidence for rescue effect in fecundity of female spiders with outbreeding opportunity

    DEFF Research Database (Denmark)

    Bilde, T.; Maklakov, A.A.; Schilling, Nadia

    2007-01-01

    avoidance can be because of low risk of inbreeding, variation in tolerance to inbreeding or high costs of outbreeding. We examined the relationship between inbreeding depression and inbreeding avoidance adaptations under two levels of inbreeding in the spider Oedothorax apicatus, asking whether preference...... for unrelated sperm via pre- and/or post-copulatory mechanisms could restore female fitness when inbreeding depression increases. Using inbred isofemale lines we provided female spiders with one or two male spiders of different relatedness in five combinations: one male sib; one male nonsib; two male sibs; two...

  6. Proteomic Characterization of Inbreeding-Related Cold Sensitivity in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Vermeulen, C.J.; Pedersen, Kamilla Sofie; Beck, Hans C.

    2013-01-01

    insight into the molecular interplay between intrinsic stress responses, inbreeding depression and temperature tolerance, we performed a proteomic characterization of a well-defined conditional inbreeding effect in a single line of Drosophila melanogaster, which suffers from extreme cold sensitivity...

  7. Componentes genéticos de médias e depressão por endogamia em populações de milho-pipoca Average genetic components and inbreeding depression in popcorn populations

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Scapim

    2006-02-01

    Full Text Available Dez populações de milho-pipoca (PR 038, PR 079, RR 046, SC 016, PR 017, BRS Angela, SC 002, PR 009, PR 023 e SE 013 foram avaliadas com os objetivos de obter estimativas de depressão por endogamia e componentes genéticos de média. O delineamento experimental utilizado foi o de blocos ao acaso em esquema de parcelas subdivididas, nos quais os tratamentos primários foram os níveis de endogamia (S1 e S0 e os tratamentos secundários as populações, com três repetições. O ensaio foi conduzido nas cidades de Maringá e Iguatemi-PR, no ano agrícola de 2001/2002. Foram avaliadas as características altura de plantas, altura de espigas, rendimento de grãos e capacidade de expansão. Foram observados menores valores de depressão por endogamia e predominância de efeitos gênicos aditivos para capacidade de expansão em relação ao rendimento de grãos. As populações BRS ANGELA e SC 002 apresentaram maior probabilidade de sucesso na obtenção de linhagens com boa capacidade de expansão.Ten popcorn populations (PR 038, PR 079, RR 046, SC 016, PR 017, BRS Angela, SC 002, PR 009, PR 023 and SE 013 were evaluated to estimate inbreeding depression and average genetic components. The experiment was a split plot in a randomized complete block design with three replications. The plots were the inbreeding levels (S1 and S0 and the sub-plots were the populations in two locations (Maringá and Iguatemi-PR during the 2001/2002 grown season. Plant and ear height, grain yield and popping expansion were evaluated. It was observed lower values of inbreeding depression and predominance of additive effects for popping expansion in relation to yield. The sucess of getting high popping expansion inbred lines is higher with BRS ANGELA and SC 002 populations.

  8. 鹅掌楸属树种近交衰退分析%Inbreeding Depression in Liriodendron Revealed by Both Phenotypic and Genotypic Characteristics

    Institute of Scientific and Technical Information of China (English)

    姚俊修; 李火根; 边黎明; 施季森

    2012-01-01

    Four types of mating offspring (ie. intra-species cross, inter-species cross, selling, and backcross) were used as experimental populations to evaluate the extent of inbreeding depression in Liriodendron. And their phenotypic traits were compared, including seed plumpness, seed germination rate, and seedling growth, as well as their genotypic feature (the percentage of homozygous SSR loci). Results showed that seed plumpness and seed germination rate exhibited the same trends, that is, the seed plumpness and seed germination rate of intra-species cross was the highest, followed by inter-species cross, backcross and selfing. The seedling growth of inter-species cross was the highest, followed by backcross, intra-species cross, and selfing. The percentage of homozygote of selfing was the highest, followed by intra-species cross, back-cross and inter-species cross. All these indicate an evident inbreeding depression occurred in Liriodendron. Meanwhile, it is found that the SSR heterozygosity of L tulipifera is higher than that of L. chinense.%异交物种易发生近交衰退.为了研究濒危树种鹅掌楸天然种群的濒危机制,以鹅掌楸属树种4种人工交配类型(种间杂交、种内杂交、回交、自交)子代为材料,从表型(种子饱满度、出苗率、苗期生长量)和基因型(SSR位点)两方面分析了鹅掌楸近交衰退状况.结果表明:子代饱满度、出苗率有相同的变异趋势,种内杂交>种间杂交>回交>自交.子代苗期生长量为种间杂交>回交>种内杂交>自交.子代纯合子比率为自交>种内杂交>回交>种间杂交,表明鹅掌楸属树种近交衰退明显.同时还发现北美鹅掌楸基因杂合度高于鹅掌楸.

  9. Combining ability, heterosis and inbreeding depression in inter specific hybrids involving greengram [ Vigna radiata (L. Wilczek] and blackgram [Vigna mungo (L. Hepper

    Directory of Open Access Journals (Sweden)

    Yashpal, M. N. Singh, N. Pathak and S. K. Saroj

    2015-03-01

    Full Text Available A line x tester analysis of interspecific hybrids involving greengram (female and blackgram (male was carried out for 11 quantitative traits. As expected in wide crosses, none of the parent was found to be good general combiner for yield. However, PDM-11, HUM-26 Azad-U-1 and KUG-427 were spotted out as superior general combiners for 2-5 yield traits. Likewise, hybrids, PDM-11 × KUG-427, HUM-26 × Azad-U-1, HUM-6 × BHU-U-1 and HUM-26 × BHU-U-1 were identified as best specific cross combinations for few yield components only. Further, economic heterosis for seed yield and few important yield traits such as, pod length, seeds per pod and 100-seed weight, was significantly negative, while it was mostly positive for days to first flowering, days to maturity, plant height, number of primary and secondary branches including pods per plant. All the crosses showing negative yield heterosis reflected positive inbreeding depression. Non-additive gene action was of prime importance for all the characters except for days to 50% flowering.

  10. Purged window apparatus utilizing heated purge gas

    Science.gov (United States)

    Ballard, Evan O.

    1984-01-01

    A purged window apparatus utilizing tangentially injected heated purge gases in the vicinity of electromagnetic radiation transmitting windows, and a tapered external mounting tube to accelerate these gases to provide a vortex flow on the window surface and a turbulent flow throughout the mounting tube. Use of this apparatus prevents backstreaming of gases under investigation which are flowing past the mouth of the mounting tube which would otherwise deposit on the windows. Lengthy spectroscopic investigations and analyses can thereby be performed without the necessity of interrupting the procedures in order to clean or replace contaminated windows.

  11. Purge water management system

    Science.gov (United States)

    Cardoso-Neto, Joao E.; Williams, Daniel W.

    1996-01-01

    A purge water management system for effectively eliminating the production of purge water when obtaining a groundwater sample from a monitoring well. In its preferred embodiment, the purge water management system comprises an expandable container, a transportation system, and a return system. The purge water management system is connected to a wellhead sampling configuration, typically permanently installed at the well site. A pump, positioned with the monitoring well, pumps groundwater through the transportation system into the expandable container, which expands in direct proportion with volume of groundwater introduced, usually three or four well volumes, yet prevents the groundwater from coming into contact with the oxygen in the air. After this quantity of groundwater has been removed from the well, a sample is taken from a sampling port, after which the groundwater in the expandable container can be returned to the monitoring well through the return system. The purge water management system prevents the purge water from coming in contact with the outside environment, especially oxygen, which might cause the constituents of the groundwater to oxidize. Therefore, by introducing the purge water back into the monitoring well, the necessity of dealing with the purge water as a hazardous waste under the Resource Conservation and Recovery Act is eliminated.

  12. The role of late-acting self-incompatibility and early-acting inbreeding depression in governing female fertility in monkshood, Aconitum kusnezoffii.

    Directory of Open Access Journals (Sweden)

    Yi-Qi Hao

    Full Text Available Reduced seed yields following self-pollination have repeatedly been observed, but the underlying mechanisms remain elusive when self-pollen tubes can readily grow into ovaries, because pre-, post-zygotic late-acting self-incompatibility (LSI, or early-acting inbreeding depression (ID can induce self-sterility. The main objective of this study was to differentiate these processes in Aconitum kusnezoffii, a plant lacking stigmatic or stylar inhibition of self-pollination. We performed a hand-pollination experiment in a natural population of A. kusnezoffii, compared seed set among five pollination treatments, and evaluated the distribution of seed size and seed set. Embryonic development suggested fertilization following self-pollination. A partial pre-zygotic LSI was suggested to account for the reduced seed set by two lines of evidence. The seed set of chase-pollination treatment significantly exceeded that of self-pollination treatment, and the proportion of unfertilized ovules was the highest following self-pollination. Meanwhile, early-acting ID, rather than post-zygotic LSI, was suggested by the findings that the size of aborted selfed seeds varied continuously and widely; and the selfed seed set both exhibited a continuous distribution and positively correlated with the crossed seed set. These results indicated that the embryos were aborted at different stages due to the expression of many deleterious alleles throughout the genome during seed maturation. No signature of post-zygotic LSI was found. Both partial pre-zygotic LSI and early-acting ID contribute to the reduction in selfed seed set in A. kusnezoffii, with pre-zygotic LSI rejecting part of the self-pollen and early-acting ID aborting part of the self-fertilized seeds.

  13. Conserving Purge Gases

    Science.gov (United States)

    Kan, K.; Blewett, L.; Nelson, T.

    1985-01-01

    Two-step flow control adjusts to dimensional changes in purged equipment. Two pressure actuated valves provide two-step control. When turbopump starts, helium flows through both valves. As pump operates its parts expand, clearance decrease and back pressure builds up on valves. At preset back pressure value, one valve closes, reducing helium flow.

  14. Inbreeding and brood stock management

    National Research Council Canada - National Science Library

    Tave, Douglas

    1999-01-01

    This manual, written for extension workers, aquaculturists, and those who work with inbreeding in cultured fish populations and describes management techniques that can be used to prevent or minimize inbreeding...

  15. The effect of inbreeding on defence against multiple enemies in Datura stramonium.

    Science.gov (United States)

    Bello-Bedoy, R; Núñez-Farfán, J

    2011-03-01

    The ability of plants to respond to natural enemies might depend on the availability of genetic variation for the optimal phenotypic expression of defence. Selfing can affect the distribution of genetic variability of plant fitness, resistance and tolerance to herbivores and pathogens. The hypothesis of inbreeding depression influencing plant defence predicts that inbreeding would reduce resistance and tolerance to damage by natural enemies relative to outcrossing. In a field experiment entailing experimentally produced inbred and outcrossed progenies, we assessed the effects of one generation of selfing on Datura stramonium resistance and tolerance to three types of natural enemies, herbivores, weevils and a virus. We also examined the effect of damage on relative growth rate (RGR), flower, fruit, and seed production in inbred and outcrossed plants. Inbreeding significantly reduced plant defence to natural enemies with an increase of 4% in herbivore damage and 8% in viral infection. These results indicate inbreeding depression in total resistance. Herbivory increased 10% inbreeding depression in seed number, but viral damage caused inbred and outcrossed plants to have similar seed production. Inbreeding and outcrossing effects on fitness components were highly variable among families, implying that different types or numbers of recessive deleterious alleles segregate following inbreeding in D. stramonium. Although inbreeding did not equally alter all the interactions, our findings indicate that inbreeding reduced plant defence to herbivores and pathogens in D. stramonium.

  16. TO PURGE OR NOT TO PURGE? VOC CONCENTRATION ...

    Science.gov (United States)

    Soil vapor surveys are commonly used as a screening technique to delineate volatile organic compound (VOC) contaminant plumes and provide information for soil sampling plans. Traditionally, three purge volumes of vapor are removed before a sample is collected. One facet of this study was to evaluate the VOC concentrations lost during purging and explore the potential implications of those losses. The vapor data was compared to collocated soil data to determine if any correlation existed between the VOC concentrations. Two different methods for soil vapor collection were compared: 1) active/micro-volume; and 2) active/macro-volume. The active/micro-volume vapor sample had total line purge volume of 1.25 mL and the active/macro-volume vapor sample had a total line purge volume of 15 mL. Six line purge volumes were collected for each vapor sampling technique, with the fourth purge volume representing the traditional sample used for site screening data. Each sample was collected by gas tight syringe and transferred to a thermal de sorption tube for sorption, transport, and analysis. Following the removal of the soil vapor samples, collocated soil samples were taken. For both active vapor sampling techniques, the VOC concentrations in the first three purge volumes exceeded the VOC concentrations in the last three purge volumes. This implies that the general rule of removal of three purge volumes prior to taking a sample for analysis could lead to underestimating the

  17. Telomere length reveals cumulative individual and transgenerational inbreeding effects in a passerine bird

    NARCIS (Netherlands)

    Bebbington, Kat; Spurgin, Lewis G; Fairfield, Eleanor A; Dugdale, Hannah L; Komdeur, Jan; Burke, Terry; Richardson, David S

    2016-01-01

    Inbreeding results in more homozygous offspring that should suffer reduced fitness, but it can be difficult to quantify these costs for several reasons. First, inbreeding depression may vary with ecological or physiological stress and only be detectable over long time periods. Second, parental homoz

  18. ZAP: Zurich Atmosphere Purge

    Science.gov (United States)

    Soto, Kurt T.; Lilly, Simon J.; Bacon, Roland; Richard, Johan; Conseil, Simon

    2016-02-01

    ZAP (Zurich Atmosphere Purge) provides sky subtraction for integral field spectroscopy; its approach is based on principal component analysis (PCA) developed for the Multi Unit Spectrographic Explorer (MUSE) integral field spectrograph. ZAP employs filtering and data segmentation to enhance the inherent capabilities of PCA for sky subtraction. ZAP reduces sky emission residuals while robustly preserving the flux and line shapes of astronomical sources; this method works in a variety of observational situations from sparse fields with a low density of sources to filled fields in which the target source fills the field of view. With the inclusion of both of these situations the method is generally applicable to many different science cases and should also be useful for other instrumentation.

  19. Estimation of inbreeding using pedigree, 50k SNP chip genotypes and full sequence data in three cattle breeds

    DEFF Research Database (Denmark)

    Zhang, Qianqian; Calus, Mario P L; Guldbrandtsen, Bernt;

    2015-01-01

    Background: Levels of inbreeding in cattle populations have increased in the past due to the use of a limited number of bulls for artificial insemination. High levels of inbreeding lead to reduced genetic diversity and inbreeding depression. Various estimators based on different sources, e.......g., pedigree or genomic data, have been used to estimate inbreeding coefficients in cattle populations. However, the comparative advantage of using full sequence data to assess inbreeding is unknown. We used pedigree and genomic data at different densities from 50k to full sequence variants to compare how......); genomic relationship matrix (GRM)-based inbreeding coefficients (FGRM); inbreeding coefficients based on excess of homozygosity (FHOM) and correlation of uniting gametes (FUNI). Estimates using ROH provided the direct estimated levels of autozygosity in the current populations and are free effects...

  20. Demographic consequences of inbreeding and outbreeding in Arnica montana: a field experiment.

    NARCIS (Netherlands)

    Luijten, S.H.; Kery, M.; Oostermeijer, J.G.B.; den Nijs, J.C.M.

    2002-01-01

    1. The genetic constitution of populations may significantly affect demography. Founder populations or isolated remnants may show inbreeding depression, while established populations can be strongly adapted to the local environment. Gene exchange between populations can lead to better performance if

  1. Exploration EVA Purge Flow Assessment

    Science.gov (United States)

    Navarro, Moses; Conger, Bruce; Campbell, Colin

    2011-01-01

    An advanced future spacesuit will require properly sized suit and helmet purge flow rates in order to sustain a crew member with a failed Portable Life Support System (PLSS) during an Extravehicular Activity (EVA). A computational fluid dynamics evaluation was performed to estimate the helmet purge flow rate required to washout carbon dioxide and to prevent the condensing ("fogging") of water vapor on the helmet visor. An additional investigation predicted the suit purge flow rate required to provide sufficient convective cooling to keep the crew member comfortable. This paper summarizes the results of these evaluations.

  2. DEPRESIÓN EN VIGOR POR ENDOGAMIA Y HETEROSIS PARA EL RENDIMIENTO Y SUS COMPONENTES EN ZAPALLO Cucurbita moschata Duch. Ex Poir INBREEDING DEPRESSION AND HETEROSIS FOR YIELD AND ITS COMPONENTS IN PUMPKIN Cucurbita moschata Duch. Ex Poir

    Directory of Open Access Journals (Sweden)

    Miguel Mariano Espitia Camacho

    2006-06-01

    Full Text Available El estudio tuvo como objetivos estimar la depresión por endogamia (DE y cuatro tipos de heterosis: promedio general (HP, promedio de progenitores (HM, heterobeltiosis (HB y útil (HU, en dos dialélos [uno entre cinco variedades (V y el otro entre cinco líneas endogamicas S1 (LS1, derivadas de éstas], para el rendimiento por planta (PFP, número de frutos por planta (NFP y peso promedio de fruto (PPF. Los 30 genotipos se evaluaron en el municipio de Candelaria (Valle del Cauca, Colombia, en un diseño de bloques completos al azar con cinco repeticiones. Se presentaron diferencias significativas (p 40 % y HU (>60 % en PFP.With the goal of estimating inbreeding depression (DE and the four types of heterosis: general average (HP, mean (HM, heterobeltiosis (HB and standard (HU, in two diallelic [one among five cross pollinated varieties (VAR and the other among five self-pollinated lines S1(LS1, derived from these], for yield/plant (PFP, number of fruits/plant (NFP and weight/fruit (PPF. The 30 genotypes were evaluated using a complete randomized design with five replicates in Candelaria (Valle del Cauca, Colombia . Significant differences (p 40 % and HU (>60 % in PFP.

  3. The effect of inbreeding on natural selection in a seed-feeding beetle.

    Science.gov (United States)

    Fox, C W

    2013-01-01

    Little is known about how inbreeding alters selection on ecologically relevant traits. Inbreeding could affect selection by changing the distribution of traits and/or fitness, or by changing the causal effect of traits on fitness. Here, I test whether selection on egg size varies with the degree of inbreeding in the seed-feeding beetle, Stator limbatus. There was strong directional selection favoring large eggs for both inbred and outbred beetles; offspring from smaller eggs had lower survivorship on a resistant host. Inbreeding treatment had no effect on the magnitude of selection on egg size; all selection coefficients were between ~0.078 and 0.096, regardless of treatment. However, inbreeding depression declined with egg size; this is because the difference in fitness between inbreds and outbreds did not change, but average fitness increased, with egg size. A consequence of this is that populations that differ in mean egg size should experience different magnitudes of inbreeding depression (all else being equal) and thus should differ in the magnitude of selection on traits that affect mating, simply as a consequence of variation in egg size. Also, maternal traits (such as egg size) that mediate stressfulness of the environment for offspring can mediate the severity of inbreeding depression.

  4. Outbreeding effects in an inbreeding insect, Cimex lectularius.

    Science.gov (United States)

    Fountain, Toby; Butlin, Roger K; Reinhardt, Klaus; Otti, Oliver

    2015-01-01

    In some species, populations with few founding individuals can be resilient to extreme inbreeding. Inbreeding seems to be the norm in the common bed bug, Cimex lectularius, a flightless insect that, nevertheless, can reach large deme sizes and persist successfully. However, bed bugs can also be dispersed passively by humans, exposing inbred populations to gene flow from genetically distant populations. The introduction of genetic variation through this outbreeding could lead to increased fitness (heterosis) or be costly by causing a loss of local adaptation or exposing genetic incompatibility between populations (outbreeding depression). Here, we addressed how inbreeding within demes and outbreeding between distant populations impact fitness over two generations in this re-emerging public health pest. We compared fitness traits of families that were inbred (mimicking reproduction following a founder event) or outbred (mimicking reproduction following a gene flow event). We found that outbreeding led to increased starvation resistance compared to inbred families, but this benefit was lost after two generations of outbreeding. No other fitness benefits of outbreeding were observed in either generation, including no differences in fecundity between the two treatments. Resilience to inbreeding is likely to result from the history of small founder events in the bed bug. Outbreeding benefits may only be detectable under stress and when heterozygosity is maximized without disruption of coadaptation. We discuss the consequences of these results both in terms of inbreeding and outbreeding in populations with genetic and spatial structuring, as well as for the recent resurgence of bed bug populations.

  5. Postcopulatory inbreeding avoidance in guppies

    National Research Council Canada - National Science Library

    Fitzpatrick, J. L; Evans, J. P

    2014-01-01

    .... Here, we examine the potential for paternity biases to favour unrelated males when their sperm compete for fertilizations though postcopulatory inbreeding avoidance mechanisms in the guppy, P oecilia reticulata...

  6. QTL mapping of inbreeding-related cold sensitivity and conditional lethality in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Vermeulen, Corneel J.; Bijlsma, R.; Loeschcke, Volker

    2008-01-01

    Inbreeding depression is a central theme within genetics, and is of specific interest for researchers within evolutionary and conservation genetics and animal and plant breeding. Inbreeding effects are thought to be caused by the joint expression of conditional and unconditional deleterious alleles...

  7. Linking inbreeding effects in captive populations with fitness in the wild: Release of replicated Drosophila melanogaster lines under different temperatures

    DEFF Research Database (Denmark)

    Kristensen, Torsten Nygård; Loeschcke, Volker; Hoffmann, Ary A.

    2008-01-01

    conditions and involve traits not easily measured under laboratory conditions. More generally, inbreeding effects measured in captive populations may not necessarily predict their field performance, and programs to purge captive populations of deleterious alleles may not necessarily lead to fitness benefits...

  8. Cyclically controlled welding purge chamber

    Science.gov (United States)

    Gallagher, Robert L. (Inventor)

    1996-01-01

    An arrangement for butt-welding cylindrical sections of large, thin-wall tanks includes a rotatable mandrel with side-by-side sets of radial position adjusters. Each set of adjusters bears on one of the tank sections adjacent the seam, to prevent the sections from sagging out-of-round. The mandrel rotates relative to the welder, so that a continuous seam is formed. A purge chamber is fixed in position behind the seam at the weld head, and is flushed with inert gas. The purge chamber includes a two-sided structure which is contiguous with the cylindrical sections and a circumferential vane to form an open-ended tube-like structure, through which the radial position adjusters pass as the mandrel and cylindrical workpiece sections rotate. The tube-like structure is formed into a chamber by a plurality of movable gates which are controlled to maintain a seal while allowing adjusters to progress through the purge chamber.

  9. 49 CFR 193.2517 - Purging.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Purging. 193.2517 Section 193.2517 Transportation...: FEDERAL SAFETY STANDARDS Operations § 193.2517 Purging. When necessary for safety, components that could accumulate significant amounts of combustible mixtures must be purged in accordance with a procedure...

  10. THE EFFECT OF INBREEDING ON THE EARLY PERFORMANCE OF FRESHWATER PRAWN, Macrobrachium rosenbergii

    Directory of Open Access Journals (Sweden)

    Imron Imron

    2009-06-01

    Full Text Available Inbreeding depression has often been considered to be responsible for the deterioration of performance in aquaculture species. Despite a crucial impact that may result from inbreeding depression, comprehensive information reviewing this subject is limited. This study was aimed to gain information on the effect of inbreeding on the early performance of freshwater prawn. The study was performed by comparing performance of inbred and outbred populations. Inbred population was established by brother-sister mating (inbreeding rate of 25% while the outbred population was formed by mating unrelated individuals. Several fitness and productivity related traits including survival, the rate of larval development, stage dispersion and growth of larvae were evaluated. Results suggest that inbred families performed poorer than that of the outbred in survival. However, inbreeding depression did not seem to occur in other traits including the rate of larval development, larval stage dispersion and growth. This study implies that to maintain genetic quality of farmed prawn stocks, inbreeding rate in farmed population must be controlled not to exceed that level. Implications that these findings may have on aquaculture practices and possible alternatives for the solutions are discussed.

  11. Academic Inbreeding in the Portuguese Academia

    Science.gov (United States)

    Tavares, Orlanda; Cardoso, Sónia; Carvalho, Teresa; Sousa, Sofia Branco; Santiago, Rui

    2015-01-01

    This paper analyses the inbreeding phenomena in Portuguese public universities. Inbreeding is defined as the recruitment of academics by the same institution that awarded their PhDs. Focusing on 1,217 PhD-holding Portuguese academics, belonging to four public universities and to six disciplinary areas, inbreeding is analysed in order to understand…

  12. Assessing effective population size, coancestry and inbreeding effects on litter size using the pedigree and SNP data in closed lines of the Iberian pig breed.

    Science.gov (United States)

    Silió, L; Barragán, C; Fernández, A I; García-Casco, J; Rodríguez, M C

    2016-04-01

    The complete pedigree of two closed Iberian pig lines (Gamito and Torbiscal), with 798 and 4077 reproducers, has been used to measure the evolution of coancestry (f) and inbreeding (F) for autosomal and X-linked genes along 16 and 28 respective equivalent discrete generations. At the last generation, the mean values of each line were f = 0.41 and 0.22, F = 0.35 and 0.18, fX  = 0.46 and 0.22 and FX  = 0.47 and 0.19, respectively. Other calculated parameters were the effective number of founders (final values, 6.8 and 35.2) and non-founders (1.5 and 2.4), founder genome equivalents (1.2 and 2.3) and effective population size (16.0 and 57.7). Measures of Torbiscal effective size based on rates of coancestry (66.1), inbreeding (65.0) and linkage disequilibrium (71.0) were estimated from whole-genome SNP genotyping data. Values of new and old inbreeding and their respective rates by generation were computed to detect purging effects of natural selection. The analysis of 6854 Torbiscal litters showed significant negative impacts of new and fast inbreeding on litter size, as expected from the purging hypothesis: -0.20 born piglets per litter by a 10% of new inbreeding, and -0.03 and -0.02 piglets by 1% of total and new inbreeding rates, respectively. The analysis performed on 1274 litters of the Gamito line failed to show purging effects. The only significant results were reductions in -0.91 and -0.17 piglets by a 10% of old and X-linked genes inbreeding, respectively. These results may be useful for some practical issues in conservation programs of farm or captive wild animals. © 2015 Blackwell Verlag GmbH.

  13. Effects of inbreeding on potential and realized immune responses in Tenebrio molitor.

    Science.gov (United States)

    Rantala, Markus J; Viitaniemi, Heidi; Roff, Derek A

    2011-06-01

    Although numerous studies on vertebrates suggest that inbreeding reduces their resistance against parasites and pathogens, studies in insects have found contradictory evidence. In this study we tested the effect of 1 generation of brother-sister mating (inbreeding) on potential and realized immune responses and other life-history traits in Tenebrio molitor. We found that inbreeding reduced adult mass, pre-adult survival and increased development time, suggesting that inbreeding reduced the condition of the adults and thus potentially made them more susceptible to physiological stress. However, we found no significant effect of inbreeding on the potential immune response (encapsulation response), but inbreeding reduced the realized immune response (resistance against the entomopathogenic fungi, Beauveria bassiana). There was a significant family effect on encapsulation response, but no family effect on the resistance against the entomopathogenic fungi. Given that this latter trait showed significant inbreeding depression and that the sample size for the family-effect analysis was small it is likely that the lack of a significant family effect is due to reduced statistical power, rather than the lack of a heritable basis to the trait. Our study highlights the importance of using pathogens and parasites in immunoecological studies.

  14. The role of inbreeding in the extinction of a European royal dynasty.

    Directory of Open Access Journals (Sweden)

    Gonzalo Alvarez

    Full Text Available The kings of the Spanish Habsburg dynasty (1516-1700 frequently married close relatives in such a way that uncle-niece, first cousins and other consanguineous unions were prevalent in that dynasty. In the historical literature, it has been suggested that inbreeding was a major cause responsible for the extinction of the dynasty when the king Charles II, physically and mentally disabled, died in 1700 and no children were born from his two marriages, but this hypothesis has not been examined from a genetic perspective. In this article, this hypothesis is checked by computing the inbreeding coefficient (F of the Spanish Habsburg kings from an extended pedigree up to 16 generations in depth and involving more than 3,000 individuals. The inbreeding coefficient of the Spanish Habsburg kings increased strongly along generations from 0.025 for king Philip I, the founder of the dynasty, to 0.254 for Charles II and several members of the dynasty had inbreeding coefficients higher than 0.20. In addition to inbreeding due to unions between close relatives, ancestral inbreeding from multiple remote ancestors makes a substantial contribution to the inbreeding coefficient of most kings. A statistically significant inbreeding depression for survival to 10 years is detected in the progenies of the Spanish Habsburg kings. The results indicate that inbreeding at the level of first cousin (F = 0.0625 exerted an adverse effect on survival of 17.8%+/-12.3. It is speculated that the simultaneous occurrence in Charles II (F = 0.254 of two different genetic disorders: combined pituitary hormone deficiency and distal renal tubular acidosis, determined by recessive alleles at two unlinked loci, could explain most of the complex clinical profile of this king, including his impotence/infertility which in last instance led to the extinction of the dynasty.

  15. The role of inbreeding in the extinction of a European royal dynasty.

    Science.gov (United States)

    Alvarez, Gonzalo; Ceballos, Francisco C; Quinteiro, Celsa

    2009-01-01

    The kings of the Spanish Habsburg dynasty (1516-1700) frequently married close relatives in such a way that uncle-niece, first cousins and other consanguineous unions were prevalent in that dynasty. In the historical literature, it has been suggested that inbreeding was a major cause responsible for the extinction of the dynasty when the king Charles II, physically and mentally disabled, died in 1700 and no children were born from his two marriages, but this hypothesis has not been examined from a genetic perspective. In this article, this hypothesis is checked by computing the inbreeding coefficient (F) of the Spanish Habsburg kings from an extended pedigree up to 16 generations in depth and involving more than 3,000 individuals. The inbreeding coefficient of the Spanish Habsburg kings increased strongly along generations from 0.025 for king Philip I, the founder of the dynasty, to 0.254 for Charles II and several members of the dynasty had inbreeding coefficients higher than 0.20. In addition to inbreeding due to unions between close relatives, ancestral inbreeding from multiple remote ancestors makes a substantial contribution to the inbreeding coefficient of most kings. A statistically significant inbreeding depression for survival to 10 years is detected in the progenies of the Spanish Habsburg kings. The results indicate that inbreeding at the level of first cousin (F = 0.0625) exerted an adverse effect on survival of 17.8%+/-12.3. It is speculated that the simultaneous occurrence in Charles II (F = 0.254) of two different genetic disorders: combined pituitary hormone deficiency and distal renal tubular acidosis, determined by recessive alleles at two unlinked loci, could explain most of the complex clinical profile of this king, including his impotence/infertility which in last instance led to the extinction of the dynasty.

  16. Effects of inbreeding and temperature stress on life history and immune function in a butterfly.

    Science.gov (United States)

    Franke, K; Fischer, K

    2013-03-01

    Theory predicts that inbreeding depression should be more pronounced under environmental stress due to an increase in the expression of recessive deleterious alleles. If so, inbred populations may be especially vulnerable to environmental change. Against this background, we here investigate effects of inbreeding, temperature stress and its interactions with inbreeding in the tropical butterfly Bicyclus anynana. We use a full-factorial design with three levels of inbreeding (F = 0/0.25/0.38) and three temperature treatments (2 h exposure to 1, 27 or 39 °C). Despite using relatively low levels of inbreeding significant inbreeding depression was found in pupal mass, pupal time, thorax mass, abdomen fat content, egg hatching success and fecundity. However, stress resistance traits (heat tolerance, immune function) were not affected by inbreeding and interactions with temperature treatments were virtually absent. We thus found no support for an increased sensitivity of inbred individuals to environmental stress, and suspect that such patterns are restricted to harsher conditions. Our temperature treatments evidently imposed stress, significantly reducing longevity, fecundity, egg hatching success and haemocyte numbers, while fat content, protein content and lysozyme activity remained unaffected. Males and females differed in all traits measured except pupal time, protein content and phenoloxidase (PO) activity. Correlation analyses revealed, among others, a trade-off between PO and lysozyme activity, and negative correlations between fat content and several other traits. We stress that more data are needed on the effects of inbreeding, temperature variation and sexual differences on insect immune function before more general conclusions can be drawn. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

  17. Purge water minimization at LEHR

    Energy Technology Data Exchange (ETDEWEB)

    Schalla, R.

    1996-11-01

    The field demonstration described in this report is being conducted as part of the Environmental Restoration Program at the Laboratory for Energy-Related Health Research (LEHR). The Environmental Restoration Program is one of several U.S. Department of Energy (DOE) waste cleanup projects designed to support by the actual use of emerging environmental management and restoration technologies. As part of an ongoing technical support mission to achieve excellence and efficiency in environmental restoration activities at LEHR, DOE requested Pacific Northwest National Laboratory`s (PNNL`s) guidance to identify the most efficient way of reducing purge water extracted by sampling pumps while still obtaining representative samples from LEHR monitoring wells.

  18. The Medical Complications Associated with Purging

    Science.gov (United States)

    Forney, K. Jean; Buchman-Schmitt, Jennifer M.; Keel, Pamela K.; Frank, Guido K.W.

    2015-01-01

    Objective Purging behaviors, including self-induced vomiting, laxative abuse, and diuretic abuse, are present across many of the eating disorders. Here we review the major medical complications of these behaviors. Method Although we identified over 100 scholarly articles describing medical complications associated with purging, most papers involved case studies or small, uncontrolled samples. Given the limited evidence base, we conducted a qualitative (rather than systematic) review to identify medical complications that have been attributed to purging behaviors. Results Medical conditions affecting the teeth, esophagus, gastrointestinal system, kidneys, skin, cardiovascular system, and musculoskeletal system were identified, with self-induced vomiting causing the most medical complications. Conclusions Purging behavior can be associated with severe medical complications across all body systems. Mental health professionals should refer patients with purging behaviors to medical providers for screening and treatment as needed. The medical work-up for individuals with eating disorders should include a comprehensive metabolic panel, complete blood count, and a full body exam including the teeth to prevent severe complications. Medical providers should screen patients for purging behaviors and associated medical complications, even in the absence of an eating disorder diagnosis, to increase the detection of eating disorders. Recognizing the link between purging and medical complications can aid in identifying potential eating disorders, particularly those that often elude detection such as purging disorder. PMID:26876429

  19. Selective purge for hydrogenation reactor recycle loop

    Science.gov (United States)

    Baker, Richard W.; Lokhandwala, Kaaeid A.

    2001-01-01

    Processes and apparatus for providing improved contaminant removal and hydrogen recovery in hydrogenation reactors, particularly in refineries and petrochemical plants. The improved contaminant removal is achieved by selective purging, by passing gases in the hydrogenation reactor recycle loop or purge stream across membranes selective in favor of the contaminant over hydrogen.

  20. Coal slurry fuel supply and purge system

    Science.gov (United States)

    McDowell, Robert E.; Basic, Steven L.; Smith, Russel M.

    1994-01-01

    A coal slurry fuel supply and purge system for a locomotive engines is disclosed which includes a slurry recirculation path, a stand-by path for circulating slurry during idle or states of the engine when slurry fuel in not required by the engine, and an engine header fluid path connected to the stand-by path, for supplying and purging slurry fuel to and from fuel injectors. A controller controls the actuation of valves to facilitate supply and purge of slurry to and from the fuel injectors. A method for supplying and purging coal slurry in a compression ignition engine is disclosed which includes controlling fluid flow devices and valves in a plurality of fluid paths to facilitate continuous slurry recirculation and supply and purge of or slurry based on the operating state of the engine.

  1. The Role of Loss of Control Eating in Purging Disorder

    Science.gov (United States)

    Forney, K. Jean; Haedt-Matt, Alissa A.; Keel, Pamela K.

    2014-01-01

    Objective Purging Disorder (PD), an Other Specified Feeding or Eating Disorder,1 is characterized by recurrent purging in the absence of binge eating. Though objectively large binge episodes are not present, individuals with PD may experience a loss of control (LOC) while eating a normal or small amounts of food. The present study sought to examine the role of LOC eating in PD using archival data from 101 women with PD. Method Participants completed diagnostic interviews and self-report questionnaires. Analyses examined the relationship between LOC eating and eating disorder features, psychopathology, personality traits, and impairment, in bivariate models and then in multivariate models controlling for purging frequency, age, and body mass index. Results Across bivariate and multivariate models, LOC eating frequency was associated with greater disinhibition around food, hunger, depressive symptoms, negative urgency, and distress and impairment. Discussion LOC eating is a clinically significant feature of PD and should be considered in future definitions of PD. Future research should examine whether LOC eating better represents a dimension of severity in PD or a specifier that may impact treatment response or course. PMID:24185981

  2. Appetite regulatory hormones in women with anorexia nervosa: binge-eating/purging versus restricting type.

    Science.gov (United States)

    Eddy, Kamryn T; Lawson, Elizabeth A; Meade, Christina; Meenaghan, Erinne; Horton, Sarah E; Misra, Madhusmita; Klibanski, Anne; Miller, Karen K

    2015-01-01

    Anorexia nervosa is a psychiatric illness characterized by low weight, disordered eating, and hallmark neuroendocrine dysfunction. Behavioral phenotypes are defined by predominant restriction or bingeing/purging; binge-eating/purging type anorexia nervosa is associated with poorer outcome. The pathophysiology underlying anorexia nervosa types is unknown, but altered hormones, known to be involved in eating behaviors, may play a role. To examine the role of anorexigenic hormones in anorexia nervosa subtypes, we examined serum levels of peptide YY (PYY; total and active [3-36] forms), brain-derived neurotrophic factor (BDNF), and leptin as primary outcomes in women with DSM-5 restricting type anorexia nervosa (n = 50), binge-eating/purging type anorexia nervosa (n = 25), and healthy controls (n = 22). In addition, women completed validated secondary outcome measures of eating disorder psychopathology (Eating Disorder Examination-Questionnaire) and depression and anxiety symptoms (Hamilton Rating Scales for Depression [HDRS] and Anxiety [HARS]). The study samples were collected from May 22, 2004, to February 7, 2012. Mean PYY 3-36 and leptin levels were lower and BDNF levels higher in binge-eating/purging type anorexia nervosa than in restricting type anorexia nervosa (all P values anorexia nervosa types were significant (P anorexia nervosa, the anorexigenic hormones PYY, BDNF, and leptin are differentially regulated between the restricting and binge/purge types. Whether these hormone pathways play etiologic roles with regard to anorexia nervosa behavioral types or are compensatory merits further study. © Copyright 2015 Physicians Postgraduate Press, Inc.

  3. The association of genotype-based inbreeding coefficient with a range of physical and psychological human traits.

    Science.gov (United States)

    Verweij, Karin J H; Abdellaoui, Abdel; Veijola, Juha; Sebert, Sylvain; Koiranen, Markku; Keller, Matthew C; Järvelin, Marjo-Riitta; Zietsch, Brendan P

    2014-01-01

    Across animal species, offspring of closely related mates exhibit lower fitness, a phenomenon called inbreeding depression. Inbreeding depression in humans is less well understood because mating between close relatives is generally rare and stigmatised, confounding investigation of its effect on fitness-relevant traits. Recently, the availability of high-density genotype data has enabled quantification of variation in distant inbreeding in 'outbred' human populations, but the low variance of inbreeding detected from genetic data in most outbred populations means large samples are required to test effects, and only a few traits have yet been studied. However, it is likely that isolated populations, or those with a small effective population size, have higher variation in inbreeding and therefore require smaller sample sizes to detect inbreeding effects. With a small effective population size and low immigration, Northern Finland is such a population. We make use of a sample of ∼5,500 'unrelated' individuals in the Northern Finnish Birth Cohort 1966 with known genotypes and measured phenotypes across a range of fitness-relevant physical and psychological traits, including birth length and adult height, body mass index (BMI), waist-to-hip ratio, blood pressure, heart rate, grip strength, educational attainment, income, marital status, handedness, health, and schizotypal features. We find significant associations in the predicted direction between individuals' inbreeding coefficient (measured by proportion of the genome in runs of homozygosity) and eight of the 18 traits investigated, significantly more than the one or two expected by chance. These results are consistent with inbreeding depression effects on a range of human traits, but further research is needed to replicate and test alternative explanations for these effects.

  4. The association of genotype-based inbreeding coefficient with a range of physical and psychological human traits.

    Directory of Open Access Journals (Sweden)

    Karin J H Verweij

    Full Text Available Across animal species, offspring of closely related mates exhibit lower fitness, a phenomenon called inbreeding depression. Inbreeding depression in humans is less well understood because mating between close relatives is generally rare and stigmatised, confounding investigation of its effect on fitness-relevant traits. Recently, the availability of high-density genotype data has enabled quantification of variation in distant inbreeding in 'outbred' human populations, but the low variance of inbreeding detected from genetic data in most outbred populations means large samples are required to test effects, and only a few traits have yet been studied. However, it is likely that isolated populations, or those with a small effective population size, have higher variation in inbreeding and therefore require smaller sample sizes to detect inbreeding effects. With a small effective population size and low immigration, Northern Finland is such a population. We make use of a sample of ∼5,500 'unrelated' individuals in the Northern Finnish Birth Cohort 1966 with known genotypes and measured phenotypes across a range of fitness-relevant physical and psychological traits, including birth length and adult height, body mass index (BMI, waist-to-hip ratio, blood pressure, heart rate, grip strength, educational attainment, income, marital status, handedness, health, and schizotypal features. We find significant associations in the predicted direction between individuals' inbreeding coefficient (measured by proportion of the genome in runs of homozygosity and eight of the 18 traits investigated, significantly more than the one or two expected by chance. These results are consistent with inbreeding depression effects on a range of human traits, but further research is needed to replicate and test alternative explanations for these effects.

  5. An Analysis of Heterosis VS. Inbreeding Effects with an Autotetraploid Cross-Fertilized Plant: MEDICAGO SATIVA L.

    Science.gov (United States)

    Gallais, A

    1984-01-01

    Self-fertilization and crossing were combined to produce a large number of levels of inbreeding and of degrees of kinship. The inbreeding effect increases with the complexity of the character and with its supposed relationship with fitness. A certain amount of heterozygosity appears to be necessary for the expression of variability. With crossing of unrelated noninbred plants, genetic variance is mainly additive, but with inbreeding its major part is nonadditive. High additivity in crossing, therefore, coexists with strong inbreeding depression. However, even in inbreeding the genetic coefficient of covariation among relatives appears to be strongly and linearly related to the classical coefficient of kinship. This means that deviations from the additive model with inbreeding could be partly due to an effect of inbreeding on variances through an effect on means. An attempt to analyze genetic effects from a theoretical model, based upon the identity by descent relationship at the level of means and of covariances between relatives, tends to show that allelic interactions are more important and nonallelic interactions are less important for a character closely related to fitness. For a complex character, these results lead to the conception of a genome organized in polygenic complementary blocks integrating epistasis and dominance. Some consequences for plant breeding are also discussed.

  6. Depressants

    Science.gov (United States)

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Depressants KidsHealth > For Teens > Depressants A A A What's ... How Can Someone Quit? Avoiding Depressants What Are Depressants? Depressants are drugs that calm nerves and relax ...

  7. Inbreeding effects on standard metabolic rate investigated at cold, benign and hot temperatures in Drosophilia melanogaster

    DEFF Research Database (Denmark)

    Jensen, Palle; Overgaard, Johannes; Loeschcke, Volker

    2014-01-01

    in replicated lines of inbred and outbred Drosophila melanogaster at stressful low, benign and stressful high temperatures. The lowest measurements of metabolic rate in our study are always associated with the low activity period of the diurnal cycle and these measurements therefore serve as good estimates...... of standard metabolic rate. Due to the potentially added costs of genetic stress in inbred lines we hypothesized that inbred individuals have increased metabolic rate compared to outbred controls and that this is more pronounced at stressful temperatures due to synergistic inbreeding by environment......Inbreeding increases homozygosity, which is known to affect the mean and variance of fitness components such as growth, fecundity and mortality rate. Across inbred lines inbreeding depression is typically observed and the variance between lines is increased in inbred compared to outbred lines...

  8. Estimation of inbreeding using pedigree, 50k SNP chip genotypes and full sequence data in three cattle breeds.

    Science.gov (United States)

    Zhang, Qianqian; Calus, Mario P L; Guldbrandtsen, Bernt; Lund, Mogens S; Sahana, Goutam

    2015-07-22

    Levels of inbreeding in cattle populations have increased in the past due to the use of a limited number of bulls for artificial insemination. High levels of inbreeding lead to reduced genetic diversity and inbreeding depression. Various estimators based on different sources, e.g., pedigree or genomic data, have been used to estimate inbreeding coefficients in cattle populations. However, the comparative advantage of using full sequence data to assess inbreeding is unknown. We used pedigree and genomic data at different densities from 50k to full sequence variants to compare how different methods performed for the estimation of inbreeding levels in three different cattle breeds. Five different estimates for inbreeding were calculated and compared in this study: pedigree based inbreeding coefficient (F(PED)); run of homozygosity (ROH)-based inbreeding coefficients (F(ROH)); genomic relationship matrix (GRM)-based inbreeding coefficients (F(GRM)); inbreeding coefficients based on excess of homozygosity (F(HOM)) and correlation of uniting gametes (F(UNI)). Estimates using ROH provided the direct estimated levels of autozygosity in the current populations and are free effects of allele frequencies and incomplete pedigrees which may increase in inaccuracy in estimation of inbreeding. The highest correlations were observed between F(ROH) estimated from the full sequence variants and the F(ROH) estimated from 50k SNP (single nucleotide polymorphism) genotypes. The estimator based on the correlation between uniting gametes (F(UNI)) using full genome sequences was also strongly correlated with F(ROH) detected from sequence data. Estimates based on ROH directly reflected levels of homozygosity and were not influenced by allele frequencies, unlike the three other estimates evaluated (F(GRM), F(HOM) and FU(NI)), which depended on estimated allele frequencies. F(PED) suffered from limited pedigree depth. Marker density affects ROH estimation. Detecting ROH based on 50k chip

  9. Performance of Gas Purge System of Absorption Refrigerating Machine

    Science.gov (United States)

    Kunugi, Yoshifumi; Ouchi, Tomihisa; Usui, Sanpei; Sugimoto, Shigeo

    Experimental studies on performance of two gas purge systems for the lithium bromide-water absorption refrigerating machine are presented in this paper. The first purge system is that the solution flow entrains the incondensable gas from the absorber in the first purge chamber, then the incondesable gas from the condenser in the second purge chamber. The second purge system is that the solution flow entrains the incondensable gas, separates it in the separator, and then returns to the refrigerating machine through the inverted U tube. As a result, purged gas rate of both gas purge systems conforms to the theoretical equation ; S=V0(P-P0), where S is purged gas rate, V0 is exhaust gas rate, P is pressure of purge chamber, and P0 is saturated vapor pressure of solution.

  10. Proteomic characterization of inbreeding-related cold sensitivity in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Cornelis J Vermeulen

    Full Text Available Inbreeding depression is a widespread phenomenon of central importance to agriculture, medicine, conservation biology and evolutionary biology. Although the population genetic principles of inbreeding depression are well understood, we know little about its functional genomic causes. To provide insight into the molecular interplay between intrinsic stress responses, inbreeding depression and temperature tolerance, we performed a proteomic characterization of a well-defined conditional inbreeding effect in a single line of Drosophila melanogaster, which suffers from extreme cold sensitivity and lethality. We identified 48 differentially expressed proteins in a conditional lethal line as compared to two control lines. These proteins were enriched for proteins involved in hexose metabolism, in particular pyruvate metabolism, and many were found to be associated with lipid particles. These processes can be linked to known cold tolerance mechanisms, such as the production of cryoprotectants, membrane remodeling and the build-up of energy reserves. We checked mRNA-expression of seven genes with large differential protein expression. Although protein expression poorly correlated with gene expression, we found a single gene (CG18067 that, after cold shock, was upregulated in the conditional lethal line both at the mRNA and protein level. Expression of CG18067 also increased in control flies after cold shock, and has previously been linked to cold exposure and chill coma recovery time. Many differentially expressed proteins in our study appear to be involved in cold tolerance in non-inbred individuals. This suggest the conditional inbreeding effect to be caused by misregulation of physiological cold tolerance mechanisms.

  11. Purge efficiency in the determination of trihalomethanes in water by purge-and-trap gas chromatography.

    Science.gov (United States)

    Ruiz-Bevia, Francisco; Fernandez-Torres, Maria J; Blasco-Alemany, Maria P

    2009-01-26

    Purge-and-trap gas chromatography-mass spectrometry (PT-GC-MS) has become an accepted method for the analysis of trihalomethanes (THMs) in water. The purge-and-trap technique is based on an efficient transfer of volatile organic compounds from the liquid (contained in the purge chamber) to the gaseous phase by bubbling with an inert gas. The aim of this work was to study the purge system's efficiency by means of several consecutive purge cycles lasting 11 min each of the same liquid sample. The concentration range chosen of THMs was very wide [5-200 microg L(-1)]. The inert gas flow rate was 40 mL min(-1), and experiments were performed at temperatures of 25, 35 and 50 degrees C. Bromoform (CHBr(3)), the least volatile compound, needed 19 cycles to be purged quantitatively at a concentration of 200 microg L(-1) and only 7 cycles at 5 microg L(-1) for a 25 mL sample at 25 degrees C. Chloroform (CHCl(3)), the most volatile compound, required 4 cycles to be fully extracted at 200 microg L(-1) and 2 at 5 microg L(-1). Finally, Novak's theoretical model, based on the distribution constant between gas and liquid phases, was used to correlate the THMs purging extraction data.

  12. Estimation of Inbreeding Coefficient and Its Effects on Lamb Survival in Sheep

    Directory of Open Access Journals (Sweden)

    mohammad almasi

    2016-04-01

    and serious genetic variation in the population. Inbreeding depression was observed for survival trait although the levels of inbreeding coefficient were acceptable in all of the breeds investigated in this study. Therefore, the general policy in the flocks should be continued to avoid mating between close relative parents and use of enough sires and dams selected per annum. Estimated inbreeding coefficients for Baluchi and Iranblack breeds showed high degree of close mating in these herd and due to the significant effect of inbreeding on survival, it is suggested that this breeding stations should use a breeding plan to avoid mating of close relative animals.

  13. Purging dissolved oxygen by nitrogen bubble aeration

    Science.gov (United States)

    Yamashita, Tatsuya; Ando, Keita

    2016-11-01

    We apply aeration with nitrogen microbubbles to water in order to see whether oxygen gas originally dissolved in the water at one atmosphere is purged by the aeration. The concentration of dissolved oxygen (DO) is detected by a commercial DO meter. To detect the dissolved nitrogen (DN) level, we observe the growth of millimetre-sized bubbles nucleated at glass surfaces in contact with the aerated water and compare it with the Epstein-Plesset theory that accounts for DO/DN diffusions and the presence of the glass surfaces. Comparisons between the experiment and the theory suggest that the DO in the water are effectively purged by the aeration.

  14. Demographic consequences of inbreeding and outbreeding in Arnica montana: A field experiment

    Science.gov (United States)

    Luijten, S.H.; Kery, M.; Oostermeijer, J.G.B.; Den, Nijs H.J.C.M.

    2002-01-01

    1. The genetic constitution of populations may significantly affect demography. Founder populations or isolated remnants may show inbreeding depression, while established populations can be strongly adapted to the local environment. Gene exchange between populations can lead to better performance if heterozygosity levels are restored (heterosis), or to reduced performance if coadapted gene complexes are disrupted (outbreeding depression). 2. Five populations of the self-incompatible perennial Arnica montana (Asteraceae) were analysed for the demographic consequences of inbreeding and of intra- and interpopulation outcrossing, using both small and large populations as donors for the latter. We analysed seed production and seed weight and monitored growth, survival and flowering of offspring introduced as seeds and as 4-week-old seedlings in a 4-year field experiment. 3. Reduced seed set after selfing was probably due to the self-incompatibility system rather than to inbreeding depression. There was a significant increase for seed set after interpopulation crosses, which resulted from the alleviation of low mate availability in one of the small populations. 4. Significant inbreeding depression was observed for growth rates of plants introduced as seedlings. We found significant heterosis for flowering probability of plants introduced as seeds, but for plants introduced as seedlings, heterosis for seedling size and flowering probability was only marginally significant. Outbreeding depression was not observed. 5. The results of this study are important for reinforcement measures in small, remnant populations. Significant differences among populations for all measured fitness components suggest that reinforcement is best achieved using material from several populations. 6. The observed higher survival of seedlings as compared with seeds suggests that it is better to plant individuals than to sow. Sowing, however, is easier and cheaper, and was more likely to eliminate

  15. Evidence of Inbreeding in Hodgkin Lymphoma.

    Directory of Open Access Journals (Sweden)

    Hauke Thomsen

    Full Text Available Genome-wide association studies (GWASs have identified several, mainly co-dominantly acting, single-nucleotide polymorphisms (SNPs associated with Hodgkin lymphoma (HL. We searched for recessively acting disease loci by performing an analysis of runs of homozygosity (ROH based on windows of homozygous SNP-blocks and by calculating genomic inbreeding coefficients on a SNP-wise basis. We used data from a previous GWAS with 906 cases and 1217 controls from a population with a long history of no matings between relatives. Ten recurrent ROHs were identified among 25 055 ROHs across all individuals but their association with HL was not genome-wide significant. All recurrent ROHs showed significant evidence for natural selection. As a novel finding genomic inbreeding among cases was significantly higher than among controls (P = 2.11*10-14 even after correcting for covariates. Higher inbreeding among the cases was mainly based on a group of individuals with a higher average length of ROHs per person. This result suggests a correlation of higher levels of inbreeding with higher cancer incidence and might reflect the existence of recessive alleles causing HL. Genomic inbreeding may result in a higher expression of deleterious recessive genes within a population.

  16. Simulated data supporting inbreeding rate estimates from incomplete pedigrees

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data release includes: (1) The data from simulations used to illustrate the behavior of inbreeding rate estimators. Estimating inbreeding rates is particularly...

  17. Mountain gorilla genomes reveal the impact of long-term population decline and inbreeding.

    Science.gov (United States)

    Xue, Yali; Prado-Martinez, Javier; Sudmant, Peter H; Narasimhan, Vagheesh; Ayub, Qasim; Szpak, Michal; Frandsen, Peter; Chen, Yuan; Yngvadottir, Bryndis; Cooper, David N; de Manuel, Marc; Hernandez-Rodriguez, Jessica; Lobon, Irene; Siegismund, Hans R; Pagani, Luca; Quail, Michael A; Hvilsom, Christina; Mudakikwa, Antoine; Eichler, Evan E; Cranfield, Michael R; Marques-Bonet, Tomas; Tyler-Smith, Chris; Scally, Aylwyn

    2015-04-10

    Mountain gorillas are an endangered great ape subspecies and a prominent focus for conservation, yet we know little about their genomic diversity and evolutionary past. We sequenced whole genomes from multiple wild individuals and compared the genomes of all four Gorilla subspecies. We found that the two eastern subspecies have experienced a prolonged population decline over the past 100,000 years, resulting in very low genetic diversity and an increased overall burden of deleterious variation. A further recent decline in the mountain gorilla population has led to extensive inbreeding, such that individuals are typically homozygous at 34% of their sequence, leading to the purging of severely deleterious recessive mutations from the population. We discuss the causes of their decline and the consequences for their future survival.

  18. Argon purge gas cooled by chill box

    Science.gov (United States)

    Spiro, L. W.

    1966-01-01

    Cooling argon purge gas by routing it through a shop-fabricated chill box reduces charring of tungsten inert gas torch head components. The argon gas is in a cooled state as it enters the torch and prevents buildup of char caused by the high concentrations of heat in the weld area during welding operations.

  19. 49 CFR 193.2615 - Isolating and purging.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Isolating and purging. 193.2615 Section 193.2615...: FEDERAL SAFETY STANDARDS Maintenance § 193.2615 Isolating and purging. (a) Before personnel begin... component must be purged in accordance with a procedure which meets the requirements of AGA...

  20. Wright and Fisher on Inbreeding and Random Drift

    OpenAIRE

    Crow, James F

    2010-01-01

    Sewall Wright and R. A. Fisher often differed, including on the meaning of inbreeding and random gene frequency drift. Fisher regarded them as quite distinct processes, whereas Wright thought that because his inbreeding coefficient measured both they should be regarded as the same. Since the effective population numbers for inbreeding and random drift are different, this would argue for the Fisher view.

  1. Estimating inbreeding coefficients from NGS data

    DEFF Research Database (Denmark)

    Vieira, Filipe Garrett; Fumagalli, Matteo; Albrechtsen, Anders;

    2013-01-01

    Most methods for Next-Generation Sequencing (NGS) data analyses incorporate information regarding allele frequencies using the assumption of Hardy-Weinberg Equilibrium (HWE) as a prior. However, many organisms including domesticated, partially selfing or with asexual life cycles show strong...... deviations from HWE. For such species, and specially for low coverage data, it is necessary to obtain estimates of inbreeding coefficients (F) for each individual beforecalling genotypes. Here, we present two methods for estimating inbreeding coefficients from NGS data based on an Expectation...

  2. Heat stress but not inbreeding affects offensive sperm competitiveness in Callosobruchus maculatus.

    Science.gov (United States)

    Lieshout, Emile; Tomkins, Joseph L; Simmons, Leigh W

    2013-09-01

    Environmental and genetic stress have well-known detrimental effects on ejaculate quality, but their concomitant effect on male fitness remains poorly understood. We used competitive fertilization assays to expose the effects of stress on offensive sperm competitive ability in the beetle Callosobruchus maculatus, a species where ejaculates make up more than 5% of male body mass. To examine the effects of environmental and genetic stress, males derived from outcrosses or sib matings were heat shocked at 50°C for 50 min during the pupal stage, while their siblings were maintained at a standard rearing temperature of 28°C. Heat-shocked males achieved only half the offensive paternity success of their siblings. While this population exhibited inbreeding depression in body size, sperm competitiveness was unaffected by inbreeding, nor did the effect of heat shock stress on sperm competitiveness depend on inbreeding status. In contrast, pupal emergence success was increased by 34% among heat-stressed individuals, regardless of their inbreeding status. Heat-shocked males' ejaculate size was 19% reduced, but they exhibited 25% increased mating duration in single mating trials. Our results highlight both the importance of stress in postcopulatory sexual selection, and the variability among stressors in affecting male fitness.

  3. Depression

    Science.gov (United States)

    ... overview URL of this page: //medlineplus.gov/ency/article/003213.htm Depression - overview To use the sharing features on this ... older adults Major depression Persistent depressive disorder Postpartum depression Premenstrual ... Review Date 1/4/2016 Updated by: Timothy Rogge, ...

  4. Inbreeding in genome-wide selection

    NARCIS (Netherlands)

    Daetwyler, H.D.; Villanueva, B.; Bijma, P.; Woolliams, J.A.

    2007-01-01

    Traditional selection methods, such as sib and best linear unbiased prediction (BLUP) selection, which increased genetic gain by increasing accuracy of evaluation have also led to an increased rate of inbreeding per generation (¿FG). This is not necessarily the case with genome-wide selection, which

  5. Air riding seal with purge cavity

    Energy Technology Data Exchange (ETDEWEB)

    Sexton, Thomas D; Mills, Jacob A

    2017-08-15

    An air riding seal for a turbine in a gas turbine engine, where an annular piston is axial moveable within an annular piston chamber formed in a stator of the turbine and forms a seal with a surface on the rotor using pressurized air that forms a cushion in a pocket of the annular piston. A purge cavity is formed on the annular piston and is connected to a purge hole that extends through the annular piston to a lower pressure region around the annular piston or through the rotor to an opposite side. The annular piston is sealed also with inner and outer seals that can be a labyrinth seal to form an additional seal than the cushion of air in the pocket to prevent the face of the air riding seal from overheating.

  6. Purging of untrustworthy recommendations from a grid

    CERN Document Server

    Kumar, P Suresh; Ramachandram, S

    2012-01-01

    In grid computing, trust has massive significance. There is lot of research to propose various models in providing trusted resource sharing mechanisms. The trust is a belief or perception that various researchers have tried to correlate with some computational model. Trust on any entity can be direct or indirect. Direct trust is the impact of either first impression over the entity or acquired during some direct interaction. Indirect trust is the trust may be due to either reputation gained or recommendations received from various recommenders of a particular domain in a grid or any other domain outside that grid or outside that grid itself. Unfortunately, malicious indirect trust leads to the misuse of valuable resources of the grid. This paper proposes the mechanism of identifying and purging the untrustworthy recommendations in the grid environment. Through the obtained results, we show the way of purging of untrustworthy entities.

  7. Well purge and sample apparatus and method

    Science.gov (United States)

    Schalla, Ronald; Smith, Ronald M.; Hall, Stephen H.; Smart, John E.; Gustafson, Gregg S.

    1995-01-01

    The present invention specifically permits purging and/or sampling of a well but only removing, at most, about 25% of the fluid volume compared to conventional methods and, at a minimum, removing none of the fluid volume from the well. The invention is an isolation assembly with a packer, pump and exhaust, that is inserted into the well. The isolation assembly is designed so that only a volume of fluid between the outside diameter of the isolation assembly and the inside diameter of the well over a fluid column height from the bottom of the well to the top of the active portion (lower annulus) is removed. The packer is positioned above the active portion thereby sealing the well and preventing any mixing or contamination of inlet fluid with fluid above the packer. Ports in the wall of the isolation assembly permit purging and sampling of the lower annulus along the height of the active portion.

  8. Depression

    DEFF Research Database (Denmark)

    Kessing, Lars Veddel; Bukh, Jens Otto Drachmann

    2014-01-01

    The prevalence of depression is not clearly established, but estimated to 3-4% in a Danish questionnaire study. Lifetime's prevalences of 12-17% are reported in other community samples. In the current diagnostic system depression is defined categorically and operationally. It has been argued......, that these diagnostic criteria represent an oversimplification, which has blurred the concept of depression. We suggest a greater emphasis on the depressed mood as the core symptom of depression, which may increase the specificity of the diagnosis. Furthermore, basic principles for the treatment of depression...

  9. Depression

    DEFF Research Database (Denmark)

    Kessing, Lars Veddel; Bukh, Jens Drachmann

    2014-01-01

    , that these diagnostic criteria represent an oversimplification, which has blurred the concept of depression. We suggest a greater emphasis on the depressed mood as the core symptom of depression, which may increase the specificity of the diagnosis. Furthermore, basic principles for the treatment of depression......The prevalence of depression is not clearly established, but estimated to 3-4% in a Danish questionnaire study. Lifetime's prevalences of 12-17% are reported in other community samples. In the current diagnostic system depression is defined categorically and operationally. It has been argued...

  10. Inbreeding avoidance influences the viability of reintroduced populations of African wild dogs (Lycaon pictus.

    Directory of Open Access Journals (Sweden)

    Penny A Becker

    Full Text Available The conservation of many fragmented and small populations of endangered African wild dogs (Lycaon pictus relies on understanding the natural processes affecting genetic diversity, demographics, and future viability. We used extensive behavioural, life-history, and genetic data from reintroduced African wild dogs in South Africa to (1 test for inbreeding avoidance via mate selection and (2 model the potential consequences of avoidance on population persistence. Results suggested that wild dogs avoided mating with kin. Inbreeding was rare in natal packs, after reproductive vacancies, and between sibling cohorts (observed on 0.8%, 12.5%, and 3.8% of occasions, respectively. Only one of the six (16.7% breeding pairs confirmed as third-order (or closer kin consisted of animals that were familiar with each other, while no other paired individuals had any prior association. Computer-simulated populations allowed to experience inbreeding had only a 1.6% probability of extinction within 100 years, whereas all populations avoiding incestuous matings became extinct due to the absence of unrelated mates. Populations that avoided mating with first-order relatives became extinct after 63 years compared with persistence of 37 and 19 years for those also prevented from second-order and third-order matings, respectively. Although stronger inbreeding avoidance maintains significantly more genetic variation, our results demonstrate the potentially severe demographic impacts of reduced numbers of suitable mates on the future viability of small, isolated wild dog populations. The rapid rate of population decline suggests that extinction may occur before inbreeding depression is observed.

  11. Banded mongooses avoid inbreeding when mating with members of the same natal group.

    Science.gov (United States)

    Sanderson, Jennifer L; Wang, Jinliang; Vitikainen, Emma I K; Cant, Michael A; Nichols, Hazel J

    2015-07-01

    Inbreeding and inbreeding avoidance are key factors in the evolution of animal societies, influencing dispersal and reproductive strategies which can affect relatedness structure and helping behaviours. In cooperative breeding systems, individuals typically avoid inbreeding through reproductive restraint and/or dispersing to breed outside their natal group. However, where groups contain multiple potential mates of varying relatedness, strategies of kin recognition and mate choice may be favoured. Here, we investigate male mate choice and female control of paternity in the banded mongoose (Mungos mungo), a cooperatively breeding mammal where both sexes are often philopatric and mating between relatives is known to occur. We find evidence suggestive of inbreeding depression in banded mongooses, indicating a benefit to avoiding breeding with relatives. Successfully breeding pairs were less related than expected under random mating, which appeared to be driven by both male choice and female control of paternity. Male banded mongooses actively guard females to gain access to mating opportunities, and this guarding behaviour is preferentially directed towards less closely related females. Guard-female relatedness did not affect the guard's probability of gaining reproductive success. However, where mate-guards are unsuccessful, they lose paternity to males that are less related to the females than themselves. Together, our results suggest that both sexes of banded mongoose use kin discrimination to avoid inbreeding. Although this strategy appears to be rare among cooperative breeders, it may be more prominent in species where relatedness to potential mates is variable, and/or where opportunities for dispersal and mating outside of the group are limited. © 2015 John Wiley & Sons Ltd.

  12. Depressants

    Science.gov (United States)

    ... judgment and mental functioning nausea and vomiting memory loss (depressants can cause users to have no memory of events that happened while they were under the influence) Long-Term Effects When people misuse depressants over a long ...

  13. Depression

    DEFF Research Database (Denmark)

    Cizza, G; Ravn, Pernille; Chrousos, G P

    2001-01-01

    Existing studies of the relationship between depression and osteoporosis have been heterogeneous in their design and use of diagnostic instruments for depression, which might have contributed to the different results on the comorbidity of these two conditions. Nevertheless, these studies reveal...... a strong association between depression and osteoporosis. Endocrine factors such as depression-induced hypersecretion of corticotropin-releasing hormone and hypercortisolism, hypogonadism, growth hormone deficiency and increased concentration of circulating interleukin 6, might play a crucial role...... in the bone loss observed in subjects suffering from major depression....

  14. Simulated data supporting inbreeding rate estimates from incomplete pedigrees

    Science.gov (United States)

    Miller, Mark P.

    2017-01-01

    This data release includes:(1) The data from simulations used to illustrate the behavior of inbreeding rate estimators. Estimating inbreeding rates is particularly difficult for natural populations because parentage information for many individuals may be incomplete. Our analyses illustrate the behavior of a newly-described inbreeding rate estimator that outperforms previously described approaches in the scientific literature.(2) Python source code ("analytical expressions", "computer simulations", and "empricial data set") that can be used to analyze these data.

  15. AP600 containment purge radiological analysis

    Energy Technology Data Exchange (ETDEWEB)

    O`Connor, M.; Schulz, J.; Tan, C. [Bechtel Power Corporation (United States)] [and others

    1995-02-01

    The AP600 Project is a passive pressurized water reactor power plant which is part of the Design Certification and First-of-a-Kind Engineering effort under the Advanced Light Water Reactor program. Included in this process is the design of the containment air filtration system which will be the subject of this paper. We will compare the practice used by previous plants with the AP600 approach to meet the goals of industry standards in sizing the containment air filtration system. The radiological aspects of design are of primary significance and will be the focus of this paper. The AP600 Project optimized the design to combine the functions of the high volumetric flow rate, low volumetric flow rate, and containment cleanup and other filtration systems into one multi-functional system. This achieves a more simplified, standardized, and lower cost design. Studies were performed to determine the possible concentrations of radioactive material in the containment atmosphere and the effectiveness of the purge system to keep concentrations within 10CFR20 limits and within offsite dose objectives. The concentrations were determined for various reactor coolant system leakage rates and containment purge modes of operation. The resultant concentrations were used to determine the containment accessibility during various stages of normal plant operation including refueling. The results of the parametric studies indicate that a dual train purge system with a capacity of 4,000 cfm per train is more than adequate to control the airborne radioactivity levels inside containment during normal plant operation and refueling, and satisfies the goals of ANSI/ANS-56.6-1986 and limits the amount of radioactive material released to the environment per ANSI/ANS 59.2-1985 to provide a safe environment for plant personnel and offsite residents.

  16. Depression

    DEFF Research Database (Denmark)

    Pouwer, Frans

    2017-01-01

    There is ample evidence that depression is000  a common comorbid health issue in people with type 1 or type 2 diabetes. Reviews have also concluded that depression in diabetes is associated with higher HbA1c levels, less optimal self-care behaviours, lower quality of life, incident vascular...... complications and higher mortality rates. However, longitudinal studies into the course of depression in people with type 1 diabetes remain scarce. In this issue of Diabetologia, Kampling and colleagues (doi: 10.1007/s00125-016-4123-0 ) report the 5 year trajectories of depression in adults with newly diagnosed...... type 1 diabetes (mean age, 28 years). Their baseline results showed that shortly after the diagnosis of type 1 diabetes a major depressive episode was diagnosed in approximately 6% of participants, while 8% suffered from an anxiety disorder. The longitudinal depression data showed that, in a 5 year...

  17. New Approach to Purging Monitoring Wells: Lower Flow Rates Reduce Required Purging Volumes and Sample Turbidity

    Science.gov (United States)

    It is generally accepted that monitoring wells must be purged to access formation water to obtain “representative” ground water quality samples. Historically anywhere from 3 to 5 well casing volumes have been removed prior to sample collection to evacuate the standing well water...

  18. Depression.

    Science.gov (United States)

    Strock, Margaret

    Approximately ten percent of the population suffers from a depressive illness each year. Although the economic cost is high, the cost in human suffering is immeasurable. To help educate the population about this disorder, this paper presents a definition of depression and its common manifestations. The symptoms that people often experience are…

  19. Depression

    DEFF Research Database (Denmark)

    Johansen, Jon O. J.

    2013-01-01

    Nyhederne er fulde af historier om depression. Overskrifter som: ’Danskerne propper sig med lykkepiller’ eller ‘depression er stadigvæk tabu’ går tit igen i dagspressen. Men hvor er nuancerne, og hvorfor gider vi læse de samme historier igen og igen? Måske er det fordi, vores egne forestillinger er...

  20. Inbreeding avoidance drives consistent variation of fine-scale genetic structure caused by dispersal in the seasonal mating system of Brandt's voles.

    Directory of Open Access Journals (Sweden)

    Xiao Hui Liu

    Full Text Available Inbreeding depression is a major evolutionary and ecological force influencing population dynamics and the evolution of inbreeding-avoidance traits such as mating systems and dispersal. Mating systems and dispersal are fundamental determinants of population genetic structure. Resolving the relationships among genetic structure, seasonal breeding-related mating systems and dispersal will facilitate our understanding of the evolution of inbreeding avoidance. The goals of this study were as follows: (i to determine whether females actively avoided mating with relatives in a group-living rodent species, Brandt's voles (Lasiopodomys brandtii, by combined analysis of their mating system, dispersal and genetic structure; and (ii to analyze the relationships among the variation in fine-genetic structure, inbreeding avoidance, season-dependent mating strategies and individual dispersal. Using both individual- and population-level analyses, we found that the majority of Brandt's vole groups consisted of close relatives. However, both group-specific FISs, an inbreeding coefficient that expresses the expected percentage rate of homozygosity arising from a given breeding system, and relatedness of mates showed no sign of inbreeding. Using group pedigrees and paternity analysis, we show that the mating system of Brandt's voles consists of a type of polygyny for males and extra-group polyandry for females, which may decrease inbreeding by increasing the frequency of mating among distantly-related individuals. The consistent variation in within-group relatedness, among-group relatedness and fine-scale genetic structures was mostly due to dispersal, which primarily occurred during the breeding season. Biologically relevant variation in the fine-scale genetic structure suggests that dispersal during the mating season may be a strategy to avoid inbreeding and drive the polygynous and extra-group polyandrous mating system of this species.

  1. Pressure-control purge panel for automatic butt welding

    Science.gov (United States)

    Lang, E. J.; Van Wagner, B. H.

    1969-01-01

    Modification of a purge panel for use in an automatic butt weld reduces the drop in pressure between the regulators and the weld head and tube purge fitting. The invention affects air regulators for plants, regulating circuits for pneumatic valves, and automatic welding machines.

  2. Negative inbreeding effects in tree fruit breeding: self-compatibility transmission in almond.

    Science.gov (United States)

    Alonso Segura, J M; Socias I Company, R

    2007-07-01

    Inbreeding depression has been observed in most fruit trees, negatively affecting the offspring of related parents. This problem is steadily increasing due to the repeated utilization of parents in breeding programmes. In almond, self-compatibility transmission from 'Tuono' to its offspring remains partially unexplained due to deviations from the expected genotype ratios. In order to test if these deviations could be due to inbreeding, the S-genotypes of the seedlings of four almond families, 'Tuono' (S(1)S(f )) x 'Ferragnès' (S(1)S(3)), 'Tuono' (S(1)S(f)) x 'Ferralise' (S(1)S(3)) and reciprocal crosses were studied. The S-genotype determination of each seedling by separation of stylar S-RNases and by S-allele-specific PCR amplification gave identical results. The ratio of S-genotypes of the family 'Tuono' x 'Ferralise' was the one least adjusted to the expected 1:1 ratio, because the number of self-compatible seedlings (S(f)S(3)) was less than a half the number of self-incompatible ones (S(1)S(3)). A mechanism acting against inbreeding would favour cross-breeding in the following generation to increase heterozygosity. This fact stresses the need to avoid crosses between related parents in fruit breeding programmes.

  3. Depression

    Science.gov (United States)

    ... Different people have different symptoms. Some symptoms of depression include: Persistent sad, anxious, or “empty” mood Feelings of hopelessness or pessimism Feelings of guilt, worthlessness, or helplessness ...

  4. Depression

    Science.gov (United States)

    ... caring for children and aging parents, abuse, and poverty may trigger depression in some people. Medical illness – ... federal government website managed by the Office on Women’s Health in the Office of the Assistant Secretary ...

  5. Thermal vacuum chamber repressurization with instrument purging

    Science.gov (United States)

    Woronowicz, Michael S.

    2016-09-01

    At the conclusion of cryogenic vacuum testing of the James Webb Space Telescope Optical Telescope Element Integrated Science Instrument Module (JWST-OTIS) in NASA Johnson Space Center's (JSCs) thermal vacuum (TV) Chamber A, contamination control (CC) engineers are postulating that chamber particulate material stirred up by the repressurization process may be kept from falling into the Integrated Science Instrument Module (ISIM) interior to some degree by activating instrument purge flows over some initial period before opening the chamber valves. This manuscript describes development of a series of models designed to describe this process. The models are strung together in tandem with a fictitious set of conditions to estimate overpressure evolution from which net outflow velocity behavior may be obtained. Creeping flow assumptions are then used to determine the maximum particle size that may be kept suspended above the ISIM aperture, keeping smaller particles from settling within the instrument module.

  6. Thermal Vacuum Chamber Repressurization with Instrument Purging

    Science.gov (United States)

    Woronowicz, Michael

    2017-01-01

    At the end of James Webb Space Telescope (JWST) OTIS (Optical Telescope Element-OTE-Integrated Science Instrument Module-ISIM) cryogenic vacuum testing in NASA Johnson Space Centers (JSCs) thermal vacuum (TV) Chamber A, contamination control (CC) engineers are mooting the idea that chamber particulate material stirred up by the repressurization process may be kept from falling into the ISIM interior to some degree by activating instrument purge flows over some initial period before opening the chamber valves. This memo describes development of a series of models designed to describe this process. These are strung together in tandem to estimate overpressure evolution from which net outflow velocity behavior may be obtained. Creeping flow assumptions are then used to determine the maximum particle size that may be kept suspended above the ISIM aperture, keeping smaller particles from settling within the instrument module.

  7. The Genetic Paradox of Invasions revisited: the potential role of inbreeding × environment interactions in invasion success.

    Science.gov (United States)

    Schrieber, Karin; Lachmuth, Susanne

    2017-05-01

    Invasive species that successfully establish, persist, and expand within an area of introduction, in spite of demographic bottlenecks that reduce their genetic diversity, represent a paradox. Bottlenecks should inhibit population growth and invasive expansion, as a decrease in genetic diversity should result in inbreeding depression, increased fixation of deleterious mutations by genetic drift (drift load), and reduced evolutionary potential to respond to novel selection pressures. Here, we focus on the problems of inbreeding depression and drift load in introduced populations as key components of the Genetic Paradox of Invasions (GPI). We briefly review published explanations for the GPI, which are based on various mechanisms (invasion history events, reproductive traits, genetic characteristics) that mediate the avoidance of inbreeding depression and drift load. We find that there is still a substantial lack of explanation and empirical evidence for explaining the GPI for strongly bottlenecked invasions, or for during critical invasion phases (e.g. initial colonization, leading edges of range expansion) where strong genetic depletion, inbreeding depression and drift load occurs. Accordingly, we suggest that discussion of the GPI should be revived to find additional mechanisms applicable to explaining invasion success for such species and invasion phases. Based on a synthesis of the literature on the population genetics of invaders and the ecology of invaded habitats, we propose that inbreeding × environment (I × E) interactions are one such mechanism that may have strong explanatory power to address the GPI. Specifically, we suggest that a temporary or permanent release from stress in invaded habitats may alleviate the negative effects of genetic depletion on fitness via I × E interactions, and present published empirical evidence supporting this hypothesis. We additionally discuss that I × E interactions can result in rapid evolutionary changes, and may even

  8. Update on Advection-Diffusion Purge Flow Model

    Science.gov (United States)

    Brieda, Lubos

    2015-01-01

    Gaseous purge is commonly used in sensitive spacecraft optical or electronic instruments to prevent infiltration of contaminants and/or water vapor. Typically, purge is sized using simplistic zero-dimensional models that do not take into account instrument geometry, surface effects, and the dependence of diffusive flux on the concentration gradient. For this reason, an axisymmetric computational fluid dynamics (CFD) simulation was recently developed to model contaminant infiltration and removal by purge. The solver uses a combined Navier-Stokes and Advection-Diffusion approach. In this talk, we report on updates in the model, namely inclusion of a particulate transport model.

  9. Verification of the ASTM G-124 Purge Equation

    Science.gov (United States)

    Robbins, Katherine E.; Davis, Samuel Eddie

    2009-01-01

    ASTM G-124 seeks to evaluate combustion characteristics of metals in high-purity (greater than 99%) oxygen atmospheres. ASTM G-124 provides the following equation to determine the minimum number of purges required to reach this level of purity in a test chamber: n = -4/log10(Pa/Ph), where "n" is the total number of purge cycles required, Ph is the absolute pressure used for the purge on each cycle and Pa is the atmospheric pressure or the vent pressure. The origin of this equation is not known and has been the source of frequent questions as to its accuracy and reliability. This paper shows the derivation of the G-124 purge equation, and experimentally explores the equation to determine if it accurately predicts the number of cycles required.

  10. A dangerous combination of binge and purge.

    Science.gov (United States)

    Culkin, Alison; Gabe, Simon M; Peake, Simon T C; Stern, Julian M

    2012-03-01

    We present a 36-year-old female diagnosed with Crohn's disease at the age of 11 years. In 2001, she underwent a total colectomy and further small bowel resection as a result of active Crohn's. Her residual anatomy consisted of 150 cm of small bowel to an end jejunostomy. Subsequently, she developed short bowel syndrome with recurrent episodes of hypomagnesaemia, hypocalcaemia, and hypokalaemia. Dietetic assessment revealed her to be severely underweight at 37 kg with a bodymass index (BMI) of 14.4 kg/m(2) . During her admission, our patient underwent psychiatric assessment and was established on home parenteral nutrition (HPN). At the time of discharge, 1 month later, her weight had increased to 44 kg (BMI = 17.7 kg/m(2) ). Over the following 12-month period, she lost weight (BMI, 15.4 mg/m(2) ; weight, 39.5 kg) and she described a high stoma output (up to 17 L) and dehydration. Assessment of her oral intake found she was consuming an estimated 14,000 kcal and 600 g protein per day. At this time, the possibility of a new form of eating disorder was discussed with the patient and she agreed that her behavior i.e., using her stoma as a purging device, fulfilled the criteria for a diagnosis of bulimia nervosa and she was referred to a specialist eating disorder unit.

  11. Depression.

    Science.gov (United States)

    McCarron, Robert M; Vanderlip, Erik R; Rado, Jeffrey

    2016-10-04

    This issue provides a clinical overview of depression, focusing on screening, diagnosis, treatment, and practice improvement. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers.

  12. Two-locus inbreeding measures for recurrent selection.

    Science.gov (United States)

    Choy, S C; Weir, B S

    1977-03-01

    For a population undergoing recurrent selection, a method is presented for determining the average inbreeding coefficients at the end of each breeding cycle. The coefficients are derived in terms of probability measures that genes are identical by descent. For the one-locus case, two digametic measures are defined and employed in the derivation of a recurrence formula for the inbreeding coefficient. Two further classes of measures, trigametic and quadrigametic, are required for transition from one cycle to the previous one to allow the calculation of the inbreeding function for the two-locus case. Numerical values of the average probability of double identity by descent for populations with various imposed assumptions are listed to illustrate the effects of linkage and population size on the accrual of inbreeding and hence of homozygosity.

  13. Analysis of genetic diversity and estimation of inbreeding coefficient ...

    African Journals Online (AJOL)

    Analysis of genetic diversity and estimation of inbreeding coefficient within ... The present work is a contribution to the knowledge of population structure and to the ... diversity that may be helpful to horse breeders in designing and managing ...

  14. Genomic Inbreeding and Relatedness in Wild Panda Populations.

    Science.gov (United States)

    Garbe, John R; Prakapenka, Dzianis; Tan, Cheng; Da, Yang

    2016-01-01

    Inbreeding and relatedness in wild panda populations are important parameters for panda conservation. Habitat loss and fragmentation are expected to increase inbreeding but the actual inbreeding levels in natural panda habitats were unknown. Using 150,025 SNPs and 14,926 SNPs selected from published whole-genome sequences, we estimated genomic inbreeding coefficients and relatedness of 49 pandas including 34 wild pandas sampled from six habitats. Qinling and Liangshan pandas had the highest levels of inbreeding and relatedness measured by genomic inbreeding and coancestry coefficients, whereas the inbreeding levels in Qionglai and Minshan were 28-45% of those in Qinling and Liangshan. Genomic coancestry coefficients between pandas from different habitats showed that panda populations from the four largest habitats, Minshan, Qionglai, Qinling and Liangshan, were genetically unrelated. Pandas between these four habitats on average shared 66.0-69.1% common alleles and 45.6-48.6% common genotypes, whereas pandas within each habitat shared 71.8-77.0% common alleles and 51.7-60.4% common genotypes. Pandas in the smaller populations of Qinling and Liangshan were more similarly to each other than pandas in the larger populations of Qionglai and Minshan according to three genomic similarity measures. Panda genetic differentiation between these habitats was positively related to their geographical distances. Most pandas separated by 200 kilometers or more shared no common ancestral alleles. The results provided a genomic quantification of the actual levels of inbreeding and relatedness among pandas in their natural habitats, provided genomic confirmation of the relationship between genetic diversity and geographical distances, and provided genomic evidence to the urgency of habitat protection.

  15. Consanguineous marriages and endemic malaria: can inbreeding increase population fitness?

    Directory of Open Access Journals (Sweden)

    Nagelkerke Nicolas

    2008-08-01

    Full Text Available Abstract Background The practice of consanguineous marriages is widespread in countries with endemic malaria. In these regions, consanguinity increases the prevalence of α+-thalassemia, which is protective against malaria. However, it also causes an excessive mortality amongst the offspring due to an increase in homozygosis of recessive lethal alleles. The aim of this study was to explore the overall effects of inbreeding on the fitness of a population infested with malaria. Methods In a stochastic computer model of population growth, the sizes of inbred and outbred populations were compared. The model has been previously validated producing results for inbred populations that have agreed with analytical predictions. Survival likelihoods for different α+-thalassemia genotypes were obtained from the odds of severe forms of disease from a field study. Survivals were further estimated for different values of mortality from malaria. Results Inbreeding increases the frequency of α+-thalassemia allele and the loss of life due to homozygosis of recessive lethal alleles; both are proportional to the coefficient of inbreeding and the frequency of alleles in population. Inbreeding-mediated decrease in mortality from malaria (produced via enhanced α+-thalassemia frequency mitigates inbreeding-related increases in fatality (produced via increased homozygosity of recessive lethals. When the death rate due to malaria is high, the net effect of inbreeding is a reduction in the overall mortality of the population. Conclusion Consanguineous marriages may increase the overall fitness of populations with endemic malaria.

  16. Inbreeding on productive and reproductive traits of dairy Gyr cattle

    Directory of Open Access Journals (Sweden)

    João Cruz Reis Filho

    2015-05-01

    Full Text Available The objective of this study was to estimate genetic parameters and to evaluate the effects of inbreeding on productive and reproductive traits of dairy Gyr cattle. Single-trait animal models were used to estimate genetic parameters and solutions for inbreeding coefficients for milk (milk 305-d, fat (fat 305-d, protein (protein 305-d, lactose (lactose 305-d, and total solids (TS 305-d yield up to 305 days of lactation, days in milk (DIM, age at first calving (AFC and calving intervals (CI. The mean inbreeding coefficient was 2.82%. The models with linear and quadratic effects of inbreeding coefficients fitted the data better than the models without or with only linear effect of inbreeding coefficient for all traits. The increase in inbreeding coefficient caused several losses in productive and reproductive traits of dairy Gyr cattle. Estimates of heritability for milk 305-d, fat 305-d, protein 305-d, lactose 305-d, TS 305-d, DIM, AFC, and CI were 0.28, 0.27, 0.22, 0.21, 0.22, 0.17, 0.20, and 0.10, respectively. It is possible to achieve genetic progress in productive traits (especially in milk 305-d and fat 305-d and age at first calving in dairy Gyr cattle through selection.

  17. The pro-Franco purge of the primary teaching profession

    Directory of Open Access Journals (Sweden)

    Juan Manuel FERNÁNDEZ SORIA

    2013-11-01

    Full Text Available The purge of primary school teaching profession, like other groups, was an instrument of political repression organized and planned in order to establish, keep and legitimise the social-political «New Order» that aroze after the victory of Franco's army. There are three points to this article. The first point establishes the state of the question on the repressive nature and conditions in Franco's Spain. The repression adopted against the school teachers has its own quality: it is more preventive than punitive, trying with it to dissuade the pedagogue action of the teaching profession, a group who never had the confidence of the new regime nor the ideological mainstays which support it, including the catolical church. The second point tries to clear this mistrust, which goes back to the times of the Spanish Second Republic; in this mistrust the purge of the schoolteachers has its arguments. The third part studies the purge of Valencian schoolteachers, and analyses its political and social characteristics, concluding that an apolitical and scantily compromised group is purged essentially due to political accusations. Though the accusations were not harsh we can confirm the hypothesis of the preventive purge of the teaching profession, a group the Franco regime needed but kept by fear. The great lozers of this repression were not only the school teachers but the Spanish society itself. A society that saw how the new pedagogy under Franco's regime cut the progress that was finally underway only a few years prior.

  18. Solute transport in a well under slow-purge and no-purge conditions

    Science.gov (United States)

    Plummer, M. A.; Britt, S. L.; Martin-Hayden, J. M.

    2010-12-01

    Non-purge sampling techniques, such as diffusion bags and in-situ sealed samplers, offer reliable and cost-effective groundwater monitoring methods that are a step closer to the goal of real-time monitoring without pumping or sample collection. Non-purge methods are, however, not yet completely accepted because questions remain about how solute concentrations in an unpurged well relate to concentrations in the adjacent formation. To answer questions about how undisturbed well water samples compare to formation concentrations, and to provide the information necessary to interpret results from non-purge monitoring systems, we have conducted a variety of physical experiments and numerical simulations of flow and transport in and through monitoring wells under low-flow and ambient flow conditions. Previous studies of flow and transport in wells used a Darcy’s law - based continuity equation for flow, which is often justified under the strong, forced-convection flow caused by pumping or large vertical hydraulic potential gradients. In our study, we focus on systems with weakly forced convection, where density-driven free convection may be of similar strength. We therefore solved Darcy’s law for porous media domains and the Navier Stokes equations for flow in the well, and coupled solution of the flow equations to that of solute transport. To illustrate expected in-well transport behavior under low-flow conditions, we present results of three particular studies: (1) time-dependent effluent concentrations from a well purged at low-flow pumping rates, (2) solute-driven density effects in a well under ambient horizontal flow and (3) temperature-driven mixing in a shallow well subject to seasonal temperature variations. Results of the first study illustrate that assumptions about the nature of in-well flow have a significant impact on effluent concentration curves even during pumping, with Poiseuille-type flow producing more rapid removal of concentration differences

  19. Recovery of nitrogen and light hydrocarbons from polyalkene purge gas

    Science.gov (United States)

    Zwilling, Daniel Patrick; Golden, Timothy Christoph; Weist, Jr., Edward Landis; Ludwig, Keith Alan

    2003-06-10

    A method for the separation of a gas mixture comprises (a) obtaining a feed gas mixture comprising nitrogen and at least one hydrocarbon having two to six carbon atoms; (b) introducing the feed gas mixture at a temperature of about 60.degree. F. to about 105.degree. F. into an adsorbent bed containing adsorbent material which selectively adsorbs the hydrocarbon, and withdrawing from the adsorbent bed an effluent gas enriched in nitrogen; (c) discontinuing the flow of the feed gas mixture into the adsorbent bed and depressurizing the adsorbent bed by withdrawing depressurization gas therefrom; (d) purging the adsorbent bed by introducing a purge gas into the bed and withdrawing therefrom an effluent gas comprising the hydrocarbon, wherein the purge gas contains nitrogen at a concentration higher than that of the nitrogen in the feed gas mixture; (e) pressurizing the adsorbent bed by introducing pressurization gas into the bed; and (f) repeating (b) through (e) in a cyclic manner.

  20. Inbreeding avoidance through non-random mating in sticklebacks.

    Science.gov (United States)

    Frommen, Joachim G; Bakker, Theo C M

    2006-06-22

    Negative effects of inbreeding are well documented in a wide range of animal taxa. Hatching success and survival of inbred offspring is reduced in many species and inbred progeny are often less attractive to potential mates. Thus, individuals should avoid mating with close kin. However, experimental evidence for inbreeding avoidance through non-random mating in vertebrates is scarce. Here, we show that gravid female three-spined sticklebacks (Gasterosteus aculeatus) when given the choice between a courting familiar brother and a courting unfamiliar non-sib prefer to mate with the non-sib and thus avoid the disadvantages of incest. We controlled for differences in males' body size and red intensity of nuptial coloration. Thus, females adjust their courting behaviour to the risk of inbreeding.

  1. Matrimonial distance, inbreeding coefficient and population size: Dhangar data.

    Science.gov (United States)

    Majumder, P P; Malhotra, K C

    1979-01-01

    Data on the distance between the birthplaces of spouses (matrimonial distance) were collected from 2,260 married individuals belonging to 21 endogamous castes of the Dhangar (shepherd) cast-cluster of Maharashtra, India. The general form of the distribution of matrimonial distances is one which is extremely positively skewed and leptokurtic. The percentage of intra-village marriages generally decreases from the southern areas of Maharashtra to the northern areas of the state, as does the inbreeding coefficient. This situation is in conformity with the socio-cultural norms regulating matrimonial choice in south and north India. An attempt has been made to relate the degree of inbreeding to the mean matrimonial distance and population size. The mean matrimonial distance is more useful in predicting the degree of inbreeding than population size.

  2. Inbreeding rate and genetic structure of cat populations in Poland.

    Science.gov (United States)

    Mucha, S; Wolc, A; Gradowska, A; Szwaczkowski, T

    2011-02-01

    The objective of the study was to analyze effective population size and inbreeding level in populations of cat breeds registered in the Polish Studbook. The Association of Purebred Cat Breeders in Poland provided access to pedigrees of 26725 cats from seven breeds. The most frequent breed was Persian, however increasing tendency in numbers of registered animals from other breeds was recorded in later years. Although the percentage of inbred individuals was increasing over time, mating of close relatives was avoided by most of the breeders, and the average inbreeding coefficient exceeded 5% only for Siberian and Russian breeds. Current analysis suggests that the Polish pedigree cat populations are not threatened by negative effects of inbreeding.

  3. Inbreeding in Mimulus guttatus reduces visitation by bumble bee pollinators.

    Directory of Open Access Journals (Sweden)

    David E Carr

    Full Text Available Inbreeding in plants typically reduces individual fitness but may also alter ecological interactions. This study examined the effect of inbreeding in the mixed-mating annual Mimulus guttatus on visitation by pollinators (Bombus impatiens in greenhouse experiments. Previous studies of M. guttatus have shown that inbreeding reduced corolla size, flower number, and pollen quantity and quality. Using controlled crosses, we produced inbred and outbred families from three different M. guttatus populations. We recorded the plant genotypes that bees visited and the number of flowers probed per visit. In our first experiment, bees were 31% more likely to visit outbred plants than those selfed for one generation and 43% more likely to visit outbred plants than those selfed for two generations. Inbreeding had only a small effect on the number of flowers probed once bees arrived at a genotype. These differences were explained partially by differences in mean floral display and mean flower size, but even when these variables were controlled statistically, the effect of inbreeding remained large and significant. In a second experiment we quantified pollen viability from inbred and self plants. Bees were 37-54% more likely to visit outbred plants, depending on the population, even when controlling for floral display size. Pollen viability proved to be as important as floral display in predicting pollinator visitation in one population, but the overall explanatory power of a multiple regression model was weak. Our data suggested that bees use cues in addition to display size, flower size, and pollen reward quality in their discrimination of inbred plants. Discrimination against inbred plants could have effects on plant fitness and thereby reinforce selection for outcrossing. Inbreeding in plant populations could also reduce resource quality for pollinators, potentially resulting in negative effects on pollinator populations.

  4. Effect of inbreeding on the incidence of retained placenta in Friesian horses

    NARCIS (Netherlands)

    Sevinga, M.; Vrijenhoek, T.; Hesselink, J.W.; Barkema, H.W.; Groen, A.F.

    2004-01-01

    This study was motivated by the hypothesis that the incidence of retained placenta (RP) in Friesian horses is associated with inbreeding. The objectives were to 1) calculate the inbreeding rate in the total registered Friesian horse population; 2) study the association of the inbreeding coefficient

  5. Inbreeding affects locomotor activity in Drosophila melanogaster at different ages

    DEFF Research Database (Denmark)

    Manenti, Tommaso; Pertoldi, Cino; Nasiri Moghadam, Neda

    2015-01-01

    The ability to move is essential for many behavioural traits closely related to fitness. Here we studied the effect of inbreeding on locomotor activity (LA) of Drosophila melanogaster at different ages under both dark and light regimes. We expected to find a decreased LA in inbred lines compared...... LA than control lines. Moreover, age per se did not affect LA neither in control nor in inbred lines, while we found a strong line by age interaction between inbred lines. Interestingly, inbreeding changed the daily activity pattern of the flies: these patterns were consistent across all control...

  6. Propellant and Purge System Contamination "2007: A Summer of Fun"

    Science.gov (United States)

    Galloway, Randy

    2010-01-01

    This slide presentation reviews the propellant and purge system contamination that occurred during the summer of 2007 at Stennis Space Center. During this period Multiple propellant/pressurant system contamination events prompted a thorough investigation, the results of which are reviewed.

  7. Well-purging criteria for sampling purgeable organic compounds

    Science.gov (United States)

    Gibs, J.; Imbrigiotta, T.E.

    1990-01-01

    The results indicate that 1) purgeable organic compound concentrations stabilized when three casing volume were purged in only 55% of the cases evaluated in this study, 2) purgeable organic compounds concentrations did not consistently follow the temporal variation of, nor stabilize at the same time as, the measure field characteristics, and 3) purging to achieve hydraulic equilibrium between casing and aquifer water consistently underestimated the time and casing volumes needed to achieve stable values of water-quality measurements in highly transmissive aquifers. The conclusion from these data is that none of the previously recommended criteria for purging a well can be applied reliably to collecting a "representative' sample of purgeable organic compounds. These results indicate that the criteria for purging a well prior to sampling for purgeable organic compounds must take into account other factors, such as the unique hydrogeologic characteristics of a site, the nature and extent of purgeable organic compounds present, and areal extent of the contamination, the well construction, and the sampling objectives of the investigation. -from Authors

  8. Purging behavior in anorexia nervosa and eating disorder not otherwise specified

    DEFF Research Database (Denmark)

    Støving, René Klinkby; Andries, Alin; Brixen, Kim Torsten

    2012-01-01

    Purging behavior in eating disorders is associated with medical risks. We aimed to compare remission rates in purging and non-purging females with anorexia nervosa (AN) and eating disorder not otherwise specified (EDNOS) in a large retrospective single center cohort. A total of 339 patients...

  9. MACRO- MICRO-PURGE SOIL GAS SAMPLING METHODS FOR THE COLLECTION OF CONTAMINANT VAPORS

    Science.gov (United States)

    Purging influence on soil gas concentrations for volatile organic compounds (VOCs), as affected by sampling tube inner diameter and sampling depth (i.e., dead-space purge volume), was evaluated at different field sites. A macro-purge sampling system consisted of a standard hollo...

  10. Extreme temperatures increase the deleterious consequences of inbreeding under laboratory and semi-natural conditions

    DEFF Research Database (Denmark)

    Kristensen, Torsten Nygård; Barker, J. Stuart F.; Pedersen, Kamilla Sofie

    2008-01-01

    The majority of experimental studies of the effects of population bottlenecks on fitness are performed under laboratory conditions, which do not account for the environmental complexity that populations face in nature. In this study, we test inbreeding depression in multiple replicates of inbred...... when compared with non-inbred lines of Drosophila melanogaster under different temperature conditions. Egg-to-adult viability, developmental time and sex ratio of emerging adults are studied under low, intermediate and high temperatures under laboratory as well as semi-natural conditions. The results...... the sex ratio with more females relative to males emerging at low temperatures, suggesting that selection against males in pre-adult life stages is stronger at low temperatures. The coefficient of variation (CV) of egg-to-adult viability within and among lines is higher for inbred flies and generally...

  11. Inbreeding avoidance in an isolated indigenous Zapotec community in the valley of Oaxaca, southern Mexico.

    Science.gov (United States)

    Little, Bertis B; Malina, Robert M

    2005-06-01

    We analyzed inbreeding using surname isonymy in an indigenous genetic isolate. The subjects were residents of a rural Zapotec-speaking community in the valley of Oaxaca, southern Mexico. The community can be classified as a genetic isolate with an average gene flow of culturally traditional patronym-matronym naming. Estimation of inbreeding from surname isonymy is facilitated by the traditional patronym-matronym name assignment among indigenous Mexican populations. A total of 2,149 individuals had valid surname patronym-matronym pairings, including 484 deceased ancestors. Surname isonymy analysis methods were used to estimate total inbreeding and to segregate it into random and nonrandom components. The surname isonymy coefficient computed from 119 isonymous surname pairings (119/2,149) was 0.0554. The estimated inbreeding coefficient from surname isonymy was 0.0138 (0.0554/4). The random and nonrandom components of inbreeding were F(r) = 0.0221 and F(n) = -0.0091, respectively. The results suggest that consanguinity is culturally avoided. Nonrandom inbreeding decreased total inbreeding by about 41%. Total estimated inbreeding by surname isonymy was 0.0138, which is similar to inbreeding estimated from a sample of pedigrees, 0.01. Socially prescribed inbreeding avoidance substantially lowered total F through negative nonrandom inbreeding. Even in the situation of genetic isolation and small effective population size (N(e)), estimated inbreeding is lower than may have otherwise occurred if inbreeding were only random. However, among the poorest individuals, socially prescribed jural rules for inbreeding avoidance failed to operate. Thus the preponderance of inbreeding appears to occur among the poor, economically disadvantaged in the community.

  12. Trait-specific consequences of inbreeding on adaptive phenotypic plasticity

    DEFF Research Database (Denmark)

    Schou, Mads Fristrup; Kristensen, Torsten Nygaard; Loeschcke, Volker

    2015-01-01

    Environmental changes may stress organisms and stimulate an adaptive phenotypic response. Effects of inbreeding often interact with the environment and can decrease fitness of inbred individuals exposed to stress more so than that of outbred individuals. Such an interaction may stem from a reduce...

  13. Minimizing inbreeding by managing genetic contributions across generations

    NARCIS (Netherlands)

    Sanchez-Rodriquez, L.; Bijma, P.; Woolliams, J.A.

    2003-01-01

    Here we present the strategy that achieves the lowest possible rate of inbreeding (DeltaF) for a population with unequal members of sires and dams with random mating. This new strategy results in a DeltaF as much as 10% lower than previously achieved. A simple and efficient approach to reducing inbr

  14. Ashcroft Pressure Switch Monitor for Low SCHe Purge Pressure

    Energy Technology Data Exchange (ETDEWEB)

    VAN KATWIJK, C.

    2000-06-21

    These 0-15 psig pressure switches are located in the SCHe helium purge lines after PCV-5*23 and before PCV-5*27. The pressure switches monitor the pressure being maintained between the two PCVs and actuate on low pressure of 15 psig. This design is used for each of the SCHe supply lines (4). Electronic output signal is NON-SAFETY (GS).

  15. Evaluation of Innovative High Pulse Rate, Purged Spark Gap Concepts

    Science.gov (United States)

    1989-06-01

    gugh the switch and the pressure loss through the gas circulation system. The pressure loss is the sum of the losses in the spark gap , flow ducting...developed to solve the mass, momentum, and energy conservation equations which govern the purging process in a spark gap flow channel following arc...formation. [2,3] In this model, gas properties and spark gap flow channel area varied with distance along the flow axis from the spark gap and with

  16. Efficient purging of deleterious mutations in plants with haploid selfing

    Energy Technology Data Exchange (ETDEWEB)

    Szovenyi, Peter [Univ. of Zurich (Switzerland); Shaw, Jon [Duke Univ., Durham, NC (United States); Yang, Xiaohan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Devos, Nicolas [Duke Univ., Durham, NC (United States)

    2014-05-30

    In diploid organisms, selfing reduces the efficiency of selection in removing deleterious mutations from a population. This need not be the case for all organisms. Some plants, for example, undergo an extreme form of selfing known as intragametophytic selfing, which immediately exposes all recessive deleterious mutations in a parental genome to selective purging. Here we ask how effectively deleterious mutations are removed from such plants. Specifically, we study the extent to which deleterious mutations accumulate in a predominantly selfing and a predominantly outcrossing pair of moss species, using genome-wide transcriptome data. We find that the selfing species purge significantly more non-synonymous mutations, as well as a greater proportion of radical amino acid changes which alter physicochemical properties of amino acids. Moreover, their purging of deleterious mutation is especially strong in conserved regions of protein-coding genes. Our observations show that selfing need not impede but can even accelerate the removal of deleterious mutations, and do so on a genome-wide scale.

  17. Biofilm Removal Using Carbon Dioxide Aerosols without Nitrogen Purge.

    Science.gov (United States)

    Hong, Seongkyeol; Jang, Jaesung

    2016-11-06

    Biofilms can cause serious concerns in many applications. Not only can they cause economic losses, but they can also present a public health hazard. Therefore, it is highly desirable to remove biofilms from surfaces. Many studies on CO2 aerosol cleaning have employed nitrogen purges to increase biofilm removal efficiency by reducing the moisture condensation generated during the cleaning. However, in this study, periodic jets of CO2 aerosols without nitrogen purges were used to remove Pseudomonas putida biofilms from polished stainless steel surfaces. CO2 aerosols are mixtures of solid and gaseous CO2 and are generated when high-pressure CO2 gas is adiabatically expanded through a nozzle. These high-speed aerosols were applied to a biofilm that had been grown for 24 hr. The removal efficiency ranged from 90.36% to 98.29% and was evaluated by measuring the fluorescence intensity of the biofilm as the treatment time was varied from 16 sec to 88 sec. We also performed experiments to compare the removal efficiencies with and without nitrogen purges; the measured biofilm removal efficiencies were not significantly different from each other (t-test, p > 0.55). Therefore, this technique can be used to clean various bio-contaminated surfaces within one minute.

  18. Leakage predictions for Rayleigh-step, helium-purge seals

    Science.gov (United States)

    Proctor, Margaret P.

    1988-01-01

    Rayleigh-step, helium purge, annular shaft seals, studied for use in liquid oxygen turbopumps, generate a hydrodynamic force that enables the seal to follow shaft perturbations. Hence, smaller clearances can be used to reduce seal leakage. FLOWCAL, a computer code developed by Mechanical Technology Incorporated, predicts gas flow rate through an annular seal with an axial pressure gradient. Analysis of a 50-mm Rayleigh-step, helium-purge, annular seal showed the flow rate increased axial pressure gradient, downstream pressure, and eccentricity ratio. Increased inlet temperature reduced leakage. Predictions made at maximum and minimum clearances (due to centrifugal and thermal growths, machining tolerances and + or - 2 percent uncertainty in the clearance measurement) placed wide boundaries on expected flow rates. The widest boundaries were set by thermal growth conditions. Predicted flow rates for a 50-mm Rayleigh-step, helium-purge, annular seal underestimated measured flow rates by three to seven times. However, the analysis did accurately predict flow rates for choked gas flow through annular seals when compared to flow rates measured in two other independent studies.

  19. Estimating inbreeding rates in natural populations: Addressing the problem of incomplete pedigrees

    Science.gov (United States)

    Miller, Mark P.; Haig, Susan M.; Ballou, Jonathan D.; Steel, E. Ashley

    2017-01-01

    Understanding and estimating inbreeding is essential for managing threatened and endangered wildlife populations. However, determination of inbreeding rates in natural populations is confounded by incomplete parentage information. We present an approach for quantifying inbreeding rates for populations with incomplete parentage information. The approach exploits knowledge of pedigree configurations that lead to inbreeding coefficients of F = 0.25 and F = 0.125, allowing for quantification of Pr(I|k): the probability of observing pedigree I given the fraction of known parents (k). We developed analytical expressions under simplifying assumptions that define properties and behavior of inbreeding rate estimators for varying values of k. We demonstrated that inbreeding is overestimated if Pr(I|k) is not taken into consideration and that bias is primarily influenced by k. By contrast, our new estimator, incorporating Pr(I|k), is unbiased over a wide range of values of kthat may be observed in empirical studies. Stochastic computer simulations that allowed complex inter- and intragenerational inbreeding produced similar results. We illustrate the effects that accounting for Pr(I|k) can have in empirical data by revisiting published analyses of Arabian oryx (Oryx leucoryx) and Red deer (Cervus elaphus). Our results demonstrate that incomplete pedigrees are not barriers for quantifying inbreeding in wild populations. Application of our approach will permit a better understanding of the role that inbreeding plays in the dynamics of populations of threatened and endangered species and may help refine our understanding of inbreeding avoidance mechanisms in the wild.

  20. Catalytic membrane reactor for tritium extraction system from He purge

    Energy Technology Data Exchange (ETDEWEB)

    Santucci, Alessia, E-mail: alessia.santucci@enea.it [ENEA for EUROfusion, Via E. Fermi 45, 00044 Frascati, Roma (Italy); Incelli, Marco [ENEA for EUROfusion, Via E. Fermi 45, 00044 Frascati, Roma (Italy); DEIM, University of Tuscia, Via del Paradiso 47, 01100 Viterbo (Italy); Sansovini, Mirko; Tosti, Silvano [ENEA for EUROfusion, Via E. Fermi 45, 00044 Frascati, Roma (Italy)

    2016-11-01

    Highlights: • In the HCBB blanket, the produced tritium is recovered by purging with helium; membrane technologies are able to separate tritium from helium. • The paper presents the results of two experimental campaigns. • In the first, a Pd–Ag diffuser for hydrogen separation is tested at several operating conditions. • In the second, the ability of a Pd–Ag membrane reactor for water decontamination is assessed by performing isotopic swamping and water gas shift reactions. - Abstract: In the Helium Cooled Pebble Bed (HCPB) blanket concept, the produced tritium is recovered purging the breeder with helium at low pressure, thus a tritium extraction system (TES) is foreseen to separate the produced tritium (which contains impurities like water) from the helium gas purge. Several R&D activities are running in parallel to experimentally identify most promising TES technologies: particularly, Pd-based membrane reactors (MR) are under investigation because of their large hydrogen selectivity, continuous operation capability, reliability and compactness. The construction and operation under DEMO relevant conditions (that presently foresee a He purge flow rate of about 10,000 Nm{sup 3}/h and a H{sub 2}/He ratio of 0.1%) of a medium scale MR is scheduled for next year, while presently preliminary experiments on a small scale reactor are performed to identify most suitable operative conditions and catalyst materials. This work presents the results of an experimental campaign carried out on a Pd-based membrane aimed at measuring the capability of this device in separating hydrogen from the helium. Many operative conditions have been investigated by considering different He/H{sub 2} feed flow ratios, several lumen pressures and reactor temperatures. Moreover, the performances of a membrane reactor (composed of a Pd–Ag tube having a wall thickness of about 113 μm, length 500 mm and diameter 10 mm) in processing the water contained in the purge gas have been

  1. Inbreeding and surnames: a projection into Easter Island's past.

    Science.gov (United States)

    González-Martín, Antonio; García-Moro, Clara; Hernández, Miguel; Moral, Pedro

    2006-03-01

    The population of Easter Island is one of the most interesting extant human communities due to its unique demographic history, its geographic isolation, and the development of an incomparable culture characterized by the towering "Moais" and its enigmatic writing. Following the colonization of its population by Polynesians from the Mangarevan Islands in the 5th century AD, the island remained isolated up until the middle of the 20th century. Under these conditions, with endogamy levels fluctuating between 61.04-96.54% and given such a small population, a high rate of inbreeding, and consequently, an elevated level of genetic relationships would be expected. Using data from church and civil records, we calculated the consanguinity of the population of Rapa Nui. The results of this analysis do not support the hypothesis of a high level of consanguinity (alpha = 0.00028 and F(t) = 0.0007, with F(r) = 0.00586 and F(n) = -0.00519), suggesting instead the existence of a strategy used to avoid marriage between close relatives. To explain these observations, the structure and exchange dynamics of the population were studied in the tribes, known locally as "Mata." The results of this analysis suggest a tendency toward the avoidance of inbreeding within tribes, in order to decrease the rate of endogamy in each group. This is consistent with ethnographic observations from the beginning of the 20th century that support the existence of strict regulations to prevent inbreeding between closely related individuals. Furthermore, we confirm that this situation dates back to a period before the "refounding" of Easter Island. Our results demonstrate that conditions of geographical isolation are not in themselves sufficient to produce an elevated inbreeding coefficient, revealing Easter Island as an interesting example of how cultural rules can shape the genetic structure of a population.

  2. Ongoing Technology and Developing Trend of Ar-blowing Purging Plug

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An introduction of the ongoing technology of ar-gon-blowing purging plugs in China was presented in this work.Gel powders were used as starting materials to enhance the high temperature mechanical properties of the purging plugs.Composite purging plug adopting ex-trusion formed gas-purging bar and slit had its surface structural design improved,which enhanced the resist-ances to thermal shock and molten steel penetration,prolonging the service life.In addition,the safety Was greatly improved by upgrading the framework and pro-duction process,enhancing the resistance to breakout.It is indicated that the developing trend is to produce pur-ging plugs of longer service life and better gas purging rate with different starting materials and structure de-signs to meet the requirements of various metallurgical processes.

  3. Metabolomic signatures of inbreeding at benign and stressful temperatures in Drosophila melanogaster.

    Science.gov (United States)

    Pedersen, Kamilla Sofie; Kristensen, Torsten Nygaard; Loeschcke, Volker; Petersen, Bent O; Duus, Jens Ø; Nielsen, Niels Chr; Malmendal, Anders

    2008-10-01

    While the population genetics of inbreeding is fairly well understood, the effects of inbreeding on the physiological and biochemical levels are not. Here we have investigated the effects of inbreeding on the Drosophila melanogaster metabolome. Metabolite fingerprints in males from five outbred and five inbred lines were studied by nuclear magnetic resonance spectroscopy after exposure to benign temperature, heat stress, or cold stress. In both the absence and the presence of temperature stress, metabolite levels were significantly different among inbred and outbred lines. The major effect of inbreeding was increased levels of maltose and decreased levels of 3-hydroxykynurenine and a galactoside [1-O-(4-O-(2-aminoethyl phosphate)-beta-d-galactopyranosyl)-x-glycerol] synthesized exclusively in the paragonial glands of Drosophila species, including D. melanogaster. The metabolomic effect of inbreeding at the benign temperature was related to gene expression data from the same inbred and outbred lines. Both gene expression and metabolite data indicate that fundamental metabolic processes are changed or modified by inbreeding. Apart from affecting mean metabolite levels, inbreeding led to an increased between-line variation in metabolite profiles compared to outbred lines. In contrast to previous observations revealing interactions between inbreeding and environmental stress on gene expression patterns and life-history traits, the effect of inbreeding on the metabolite profile was similar across the different temperature treatments.

  4. Inbreeding among Caribbean Hispanics from the Dominican Republic and its effects on risk of Alzheimer disease.

    Science.gov (United States)

    Vardarajan, Badri N; Schaid, Daniel J; Reitz, Christiane; Lantigua, Rafael; Medrano, Martin; Jiménez-Velázquez, Ivonne Z; Lee, Joseph H; Ghani, Mahdi; Rogaeva, Ekaterina; St George-Hyslop, Peter; Mayeux, Richard P

    2015-08-01

    Inbreeding can be associated with a modification of disease risk due to excess homozygosity of recessive alleles affecting a wide range of phenotypes. We estimated the inbreeding coefficient in Caribbean Hispanics and examined its effects on risk of late-onset Alzheimer disease. The inbreeding coefficient was calculated in 3,392 subjects (1,451 late-onset Alzheimer disease patients and 1,941 age-matched healthy controls) of Caribbean Hispanic ancestry using 177,997 nearly independent single-nucleotide polymorphisms from genome-wide array. The inbreeding coefficient was estimated using the excess homozygosity method with and without adjusting for admixture. The average inbreeding coefficient in Caribbean Hispanics without accounting for admixture was F = 0.018 (±0.048), suggesting a mating equivalent to that of second cousins or second cousins once removed. Adjusting for admixture from three parent populations, the average inbreeding coefficient was found to be 0.0034 (±0.019) or close to third-cousin mating. Inbreeding coefficient was a significant predictor of Alzheimer disease when age, sex, and APOE genotype were used as adjusting covariates (P = 0.03). The average inbreeding coefficient of this population is significantly higher than that of the general Caucasian populations in North America. The high rate of inbreeding resulting in increased frequency of recessive variants is advantageous for the identification of rare variants associated with late-onset Alzheimer disease.Genet Med 17 8, 639-643.

  5. Facets of negative affect prior to and following binge-only, purge-only, and binge/purge events in women with bulimia nervosa.

    Science.gov (United States)

    Berg, Kelly C; Crosby, Ross D; Cao, Li; Peterson, Carol B; Engel, Scott G; Mitchell, James E; Wonderlich, Stephen A

    2013-02-01

    Ecological momentary assessment (EMA) data suggest that global negative affect (NA) increases prior to and decreases following episodes of binge eating and purging, providing support for the affect regulation model of BN. The current study examined whether facets of NA are differentially related to bulimic behaviors. Women with bulimia nervosa (BN; n = 133) completed a 2-week EMA protocol. Momentary assessments of 4 facets of NA (Fear, Guilt, Hostility, and Sadness) were derived from the PANAS subscales. Trajectories of the NA facets were modeled prior to and following binge-only, purge-only, and binge/purge events. Fear, Guilt, Hostility, and Sadness increased prior to and decreased following binge-only and binge/purge events. The same results were found for purge-only events, with the exception that Hostility did not increase significantly prior to purging. Notably, ratings of Guilt were higher than those of Fear, Hostility, and Sadness at the time of binge-only and binge/purge events. Furthermore, post hoc analyses demonstrate that Guilt increased prior to and decreased following the 3 behavior types, even after controlling for Fear, Hostility, and Sadness. These results provide further support for the affect regulation model of BN and also suggest that guilt may be particularly important to the pathology of BN.

  6. Interpersonal problems across restrictive and binge-purge samples: data from a community-based eating disorders clinic.

    Science.gov (United States)

    Raykos, Bronwyn C; McEvoy, Peter M; Carter, Olivia; Fursland, Anthea; Nathan, Paula

    2014-08-01

    Contemporary models of eating disorders suggest that interpersonal problems contribute to the maintenance of eating disorders. This study examined whether baseline interpersonal problems differed across eating disorder diagnoses and across eating disorder subtypes ("restrictors" vs. "binge-purge" patients) in a large clinical sample. Patients with a primary eating disorder diagnosis (N=406) completed measures of interpersonal problems, eating disorder symptoms, and mood prior to treatment at a specialist eating disorder clinic. Across the sample, more severe eating disorder psychopathology was associated with significantly greater difficulty socializing. Anorexia Nervosa (AN)/restrictor patients reported significantly greater difficulty socializing than Bulimia Nervosa (BN)/binge-purge patients. AN patients reported significantly greater difficulty on a measure of competitiveness/assertiveness compared to BN and Eating Disorder Not Otherwise Specified patients. All findings were significant after controlling for comorbid depression and anxiety symptoms. Interpersonal problems appear to be unique risk factors for eating disorders. Specific interpersonal mechanisms include difficulties socializing and being assertive, which were most pronounced in AN patients. These findings provide potential avenues for enhancing interventions, such as adjunctive assertiveness training for AN.

  7. Experimental study on the optimal purge duration of a proton exchange membrane fuel cell with a dead-ended anode

    Science.gov (United States)

    Lin, Yu-Fen; Chen, Yong-Song

    2017-02-01

    When a proton exchange membrane fuel cell (PEMFC) is operated with a dead-ended anode, impurities gradually accumulate within the anode, resulting in a performance drop. An anode purge is thereby ultimately required to remove impurities within the anode. A purge strategy comprises purge interval (valve closed) and purge duration (valve is open). A short purge interval causes frequent and unnecessary activation of the valve, whereas a long purge interval leads to excessive impurity accumulation. A short purge duration causes an incomplete performance recovery, whereas a long purge duration results in low hydrogen utilization. In this study, a series of experimental trials was conducted to simultaneously measure the hydrogen supply rate and power generation of a PEMFC at a frequency of 50 Hz for various operating current density levels and purge durations. The effect of purge duration on the cell's energy efficiency was subsequently analyzed and discussed. The results showed that the optimal purge duration for the PEMFC was approximately 0.2 s. Based on the results of this study, a methodical process for determining optimal purge durations was ultimately proposed for widespread application. Purging approximately one-fourth of anode gas can obtain optimal energy efficiency for a PEMFC with a dead-ended anode.

  8. Inbreeding among some Brahman populations of Tamil Nadu.

    Science.gov (United States)

    Srinivasan, S; Mukherjee, D P

    1976-01-01

    A statewide survey of four endogamous Brahman populations of Tamil Nadu reveals a low level of inbreeding in three of them. In the fourth population, the Thengalai, the level is higher, but not as high as in other social castes. The Tamil Brahmans rank next to the Telugu and the Kanarese Brahmans in this respect. Uncle-niece marriages also occur as in Telugu-speaking populations, and these exceed in the two Ayyangar populations in comparison to the Ayyar. A decline of first-cousin marriages and an increase of uncle-niece marriages are detected in the first two living generations in each population.

  9. Behavioral, emotional, and situational context of purging episodes in anorexia nervosa

    Science.gov (United States)

    Goldschmidt, Andrea B.; Accurso, Erin C.; Schreiber-Gregory, Deanna N.; Crosby, Ross D.; Cao, Li; Engel, Scott G.; Mitchell, James E.; Crow, Scott J.; Peterson, Carol B.; Le Grange, Daniel; Wonderlich, Stephen A.

    2015-01-01

    Objective The current study examined behavioral, emotional, and situational factors involved in purging among women with anorexia nervosa (AN). Methods Women with AN (n=118) completed a two-week ecological momentary assessment protocol involving daily reports of eating disorder behaviors, mood, and stressful events. Generalized estimating equations examined the likelihood and context of purging following eating episodes involving both overeating and loss of control (binge eating; BE); loss of control only (LOC); overeating only (OE); and neither loss of control nor overeating (non-pathological eating; NE). Results Relative to NE, purging was more likely to occur following BE, LOC, and OE (Wald chi-square=18.05; p<.001). BE was more strongly associated with subsequent purging than LOC but not OE; the latter two did not differ from one another. Negative affect predicted purging following NE (Wald chi-square=7.71; p=.005). Conclusion Binge eating involving large amounts of food was the strongest predictor of purging in AN, which challenges the notion that loss of control is the most salient aspect of experiencing distress in bulimia nervosa and binge eating disorder. Parallel to findings from the binge eating literature, negative affect strongly predicted purging following non-pathological eating. Further research should clarify the function and triggers of purging in AN. PMID:25643935

  10. From Promise to Purge: The First Years of St. Petersburg University.

    Science.gov (United States)

    Whittaker, Cynthia H.

    1978-01-01

    Discusses the development of St. Petersburg University, Russia, from its inception in 1819 when it was composed of dedicated, eager scholars to the purges in 1821. Concludes that Tsar Alexander I was instrumental in these purges because of his fear that the ideals of European enlightenment in education and politics fostered by the university would…

  11. Chinese Standards on Refractories Purging Plugs and Well Blocks for Refining Ladle

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaohui

    2009-01-01

    @@ 1 Scope This standard specifies the classification,technical requirements,test methods,inspection rules,marking,packing,transportation,storage and quality certificate of purging plugs and well blocks for refining ladle. This standard is applicable to the directional slit purging plugs and well blocks for refining ladle.

  12. Effects of inbreeding on survival, body weight and fluctuating asymmetry (FA) in Nile tilapia, Oreochromis niloticus

    NARCIS (Netherlands)

    Fessehaye, Y.; Komen, J.; Rezk, M.A.; Arendonk, van J.A.M.; Bovenhuis, H.

    2007-01-01

    The present study investigated the effects of different levels of inbreeding on survival, growth, body weight and fluctuating asymmetry (FA) in O. niloticus. We mated 20 sires and 35 dams in a full-sib/half-sib mating design to produce 35 full-sib families with expected level of inbreeding (F%.) of

  13. Allometric and non-allometric consequences of inbreeding on Drosophila melanogaster wings

    DEFF Research Database (Denmark)

    Trotta, Vincenzo; Cavicchi, Sandro; Guerra, Daniela

    2011-01-01

    Inbreeding is expected to increase the variability in size and shape within populations. The distinct effects of inbreeding on size and shape suggest that they are governed by different developmental pathways. One unresolved question is whether the non-allometric shape component is partially unco...

  14. Academic Inbreeding: Exploring Its Characteristics and Rationale in Japanese Universities Using a Qualitative Perspective

    Science.gov (United States)

    Horta, Hugo; Sato, Machi; Yonezawa, Akiyoshi

    2011-01-01

    This study analyses why and how academic inbreeding as a recruitment practice continues to prevail in Japan, a country with a mature higher education system, where high rates of academic inbreeding endure in most of the research-oriented universities in spite of several higher education reforms. Based on a qualitative analysis, we disclose three…

  15. Marker-assisted selection reduces expected inbreeding but can result in large effects of hitchhiking.

    Science.gov (United States)

    Pedersen, L D; Sørensen, A C; Berg, P

    2010-06-01

    We used computer simulations to investigate to what extent true inbreeding, i.e. identity-by-descent, is affected by the use of marker-assisted selection (MAS) relative to traditional best linear unbiased predictions (BLUP) selection. The effect was studied by varying the heritability (h(2) = 0.04 vs. 0.25), the marker distance (MAS vs. selection on the gene, GAS), the favourable QTL allele effect (alpha = 0.118 vs. 0.236) and the initial frequency of the favourable QTL allele (p = 0.01 vs. 0.1) in a population resembling the breeding nucleus of a dairy cattle population. The simulated genome consisted of two chromosomes of 100 cM each in addition to a polygenic component. On chromosome 1, a biallelic QTL as well as 4 markers were simulated in linkage disequilibrium. Chromosome 2 was selectively neutral. The results showed that, while reducing pedigree estimated inbreeding, MAS and GAS did not always reduce true inbreeding at the QTL relative to BLUP. MAS and GAS differs from BLUP by increasing the weight on Mendelian sampling terms and thereby lowering inbreeding, while increasing the fixation rate of the favourable QTL allele and thereby increasing inbreeding. The total outcome in terms of inbreeding at the QTL depends on the balance between these two effects. In addition, as a result of hitchhiking, MAS results in extra inbreeding in the region surrounding QTL, which could affect the overall genomic inbreeding.

  16. The effects of inbreeding and heat stress on male sterility in Drosophila melanogaster

    NARCIS (Netherlands)

    Pedersen, Louise Dybdahl; Pedersen, Asger Roer; Bijlsma, R.; Bundgaard, Jorgen

    2011-01-01

    Understanding the consequences of inbreeding in combination with stress is important for the persistence of small endangered populations in a changing environment. Inbreeding and stress can influence the population at all stages of the life cycle, and in the last two decades a number of studies have

  17. Estimate of Inbreeding Coefficient and Its Effects on Reproductive Traits of Dairy Herds in Isfahan Province

    Directory of Open Access Journals (Sweden)

    S. Gholizadeh

    2016-06-01

    Full Text Available This study was carried out to study the inbreeding coefficient and its effect on reproductive performance of dairy cows (age at first calving, calving interval and open days in Isfahan province. Records of 31,977 (primiparous cows, 36,982 and 51,423 (multiparous cows for age at first calving, calving interval and open days were used, respectively. The inbreeding coefficients of animals were calculated using pedigree information of 78,425 females and 8,056 males, which were born from 1963 to 2009. The overall mean and maximum inbreeding coefficients in Holstein cows were 2.33% and 31.30%, respectively. The results showed that 57,234 animals were inbred with 3.57% inbreeding coefficient. Regression coefficients on inbreeding coefficient for age at first calving, calving interval and open days were 0.589±0.21, 1.08±0.15 and 0.27±12, respectively. Estimated inbreeding indicated significantly negative effect on the reproductive traits in different parturition periods. The results revealed that the average inbreeding trend was increased in the dairy herds. The increased inbreeding was due to close mating systems between the candidates, and it showed negative effects on the reproductive traits in Isfahan dairy herds.

  18. ANALYSIS OF PENTACHLOROPHENOL IN WATER BY PURGE AND TRAP CONCENTRATOR COUPLED TOGAS CHROMATOGRAPHY

    Institute of Scientific and Technical Information of China (English)

    Huixia Lan; Yuancai Chen; Zhonghao Chen

    2004-01-01

    It is convenient and time saving to analyze pentachlorophenol (PCP) in water by purge and trap concentrator coupled to gas chromatography that avoids employing a great deal of organic solvent: In this paper, the appropriate purge and trap conditions of PCP are determined: the trapped sorbent is TenaxGC; the purge gas is pure nitrogen and purge flow is 40ml/min; the purge time is 30min. A series of standard PCP water samples 5, 10, 50, 100, 200,400, 800, 1000ppb are analyzed in order to obtain standard curve, and the linear regressive equation obtained is Y=109.65X-687.72, which correlation coefficient r is 0.9949. The precision of the method is determined with 0.5ppb PCP water sample, and the standard deviation measured is 3%. The detection limit for PCP is 0.2ppb.

  19. ANALYSIS OF PENTACHLOROPHENOL IN WATER BY PURGE AND TRAP CONCENTRATOR COUPLED TO GAS CHROMATOGRAPHY

    Institute of Scientific and Technical Information of China (English)

    HuixiaLan; YuancaiChen; ZhonghaoChen

    2004-01-01

    It is convenient and time saving to analyze pentachlorophenol (PCP) in water by purge and trap concentrator coupled to gas chromatography that avoids employing a great deal of organic solvent. In this paper, the appropriate purge and trap conditions of PCP are determined: the trapped sorbent is TenaxGC; the purge gas is pure nitrogen and purge flow is 40ml/min; the purge time is 30min. A series of standard PCP water samples 5, 10, 50, 100, 200, 400, 800, 1000ppb are analyzed in order to obtain standard curve, and the linear regressive equation obtained is Y=109.65X-687.72, which correlation coefficient r is 0.9949. The precision of the method is determined with 0.5ppb PCP water sample, and the standard deviation measured is 3%. The detection limit for PCP is 0.2ppb.

  20. Effects of Purge-Flow Rate on Microbubble Capture in Radial Arterial-Line Filters.

    Science.gov (United States)

    Herbst, Daniel P

    2016-09-01

    The process of microbubble filtration from blood is complex and highly dependent on the forces of flow and buoyancy. To protect the patient from air emboli, arterial-line filters commonly use a micropore screen, a large volume housing with purpose-built shape, and a purge port to trap, separate, and remove circulating microbubbles. Although it has been proposed that an insufficient buoyancy force renders the purge port ineffective at removing microbubbles smaller than 500 μm, this research attempts to investigate the purge flow of an arterial-line filter to better understand the microbubble removal function in a typical radial filter design. As its primary objective, the study aims to determine the effect of purge-flow rate on bubble capture using air bolus injections from a syringe pump with 22-gauge needle and Doppler ultrasound bubble detection. The measureable bubble size generated in the test circuit ranged between 30 and 500 μm, while purge flow was varied between .1 and .5 L/min for testing. Statistical analysis of the test data was handled using a repeated measures design with significance set at p purge flows yielded higher bubble counts, but the effect of purge-flow rate on bubble capture decreased as bubble size increased. Results also showed that purge flow from the test filter was capable of capturing all bubble sizes being generated over the entire flow range tested, and confirms utility of the purge port in removing microbubbles smaller than 500 μm. By analyzing bubble counts in the purge flow of a typical radial-filter design, this study demonstrates that currently available micropore filter technology is capable of removing the size range of bubbles that commonly pass through modern pump-oxygenator systems and should continue to be considered during extracorporeal circulation as a measure to improve patient safety.

  1. Polyandry facilitates postcopulatory inbreeding avoidance in house mice.

    Science.gov (United States)

    Firman, Renée C; Simmons, Leigh W

    2008-03-01

    The avoidance of genetic incompatibilities between parental genotypes has been proposed to account for the evolution of polyandry. An extension of this hypothesis suggests polyandry may provide an opportunity for females to avoid the cost of inbreeding by exploiting postcopulatory mechanisms that bias paternity toward unrelated male genotypes. Here we test the inbreeding avoidance hypothesis in house mice by experimentally manipulating genetic compatibility via matings between siblings and nonsiblings. We observed little difference in reproductive success between females mated to two siblings or females mated to two nonsiblings. Females mated to both a sibling and a nonsibling tended to have a lower litter survival, but only when the first male to mate was a sibling. Microsatellite data revealed that paternity was biased toward nonsiblings when a female mated with both a sibling and a nonsibling. Unlike previous studies of invertebrates, paternity bias toward the sibling male was independent of mating sequence. We provide one of the first empirical demonstrations that polyandry facilitates postcopulatory sexual selection in a vertebrate. We discuss this result in relation to the possibility of selective fertilization of ova based on major histocompatibility complex (MHC) haploid expression of sperm.

  2. Purge Monitoring Technology for Gaseous Helium (GHe) Conservation

    Science.gov (United States)

    Dickey, Jonathan; Lansaw, John

    2010-01-01

    John C. Stennis Space Center provides rocket engine propulsion testing for the NASA space programs. Since the development of the Space Shuttle, every Space Shuttle Main Engine (SSME) has gone through acceptance testing before going to Kennedy Space Center for integration into the Space Shuttle. The SSME is a large cryogenic rocket engine that used Liquid Oxygen (LO2) and Liquid Hydrogen (LH2) as propellants. Due to the extremely cold cryogenic conditions of this environment, an inert gas, helium, is used as a purge for the engine and propellant lines since it can be used without freezing in the cryogenic environment. As NASA moves forward with the development of the new ARES V launch system, the main engines as well as the upper stage engine will use cryogenic propellants and will require gaseous helium during the development testing of each of these engines. The main engine for the ARES V will be similar in size to the SSME.

  3. Group cognitive behavioral treatment in female soldiers diagnosed with binge/purge eating disorders.

    Science.gov (United States)

    Carter, Rinat; Yanykulovitch-Levy, Dana; Wertheim, Hadas; Gordon-Erez, Shirley; Shahimov, Meital; Weizman, Abraham; Stein, Daniel

    2016-01-01

    Cognitive behavioral treatment (CBT) is the recommended intervention in bulimia nervosa (BN) and eating disorders not otherwise specified with binge/purge (EDNOS-B/P) symptoms. There are fewer data on its application in a group format. We sought to investigate the effect of group CBT in female soldiers with B/P symptomatology in an open trial design. For this purpose we assessed 64 female soldiers serving in the Israeli Defense Force diagnosed with BN and EDNOS-B/P who participated in a group CBT format of 16 weekly sessions and one follow-up session. In this study, 42 participants (65.6%) completed treatment and 22 participants (34.4%) did not. A total of 39 treatment completers (92.8% of treatment completers) and 19 non-completers (86.4% of treatment non-completers) were assessed around 12 months after treatment. Participants completed at baseline and following treatment questionnaires assessing eating-related symptoms, depression, anxiety, and overall functioning. At follow-up they were assessed for eating-related symptoms. Our findings show only minimal baseline differences between treatment completers and non-completers. Significant improvement from baseline to post-treatment was shown for B/P and restrictive symptoms, depression, anxiety, and overall functioning. At that time, more than a third of treatment completers were abstinent from binging and more than a half from vomiting. The improvement in B/P and restricting symptoms was maintained at 1 year follow-up for treatment completers. At that time around 60% were abstinent from binging and more than 70% from vomiting. Participants not completing treatment were also improved at follow-up but to a lesser extent. The findings of the present study suggest that group CBT may be effective for the treatment of female soldiers with BN and EDNOS-B/P.

  4. Effects of inbreeding on reproductive success, performance, litter size, and survival in captive red wolves (Canis rufus).

    Science.gov (United States)

    Rabon, David R; Waddell, William

    2010-01-01

    Captive-breeding programs have been widely used in the conservation of imperiled species, but the effects of inbreeding, frequently expressed in traits related to fitness, are nearly unavoidable in small populations with few founders. Following its planned extirpation in the wild, the endangered red wolf (Canis rufus) was preserved in captivity with just 14 founders. In this study, we evaluated the captive red wolf population for relationships between inbreeding and reproductive performance and fitness. Over 30 years of managed breeding, the level of inbreeding in the captive population has increased, and litter size has declined. Inbreeding levels were lower in sire and dam wolves that reproduced than in those that did not reproduce. However, there was no difference in the inbreeding level of actual litters and predicted litters. Litter size was negatively affected by offspring and paternal levels of inbreeding, but the effect of inbreeding on offspring survival was restricted to a positive influence. There was no apparent relationship between inbreeding and method of rearing offspring. The observable effects of inbreeding in the captive red wolf population currently do not appear to be a limiting factor in the conservation of the red wolf population. Additional studies exploring the extent of the effects of inbreeding will be required as inbreeding levels increase in the captive population.

  5. Effect of inbreeding on the incidence of retained placenta in Friesian horses.

    Science.gov (United States)

    Sevinga, M; Vrijenhoek, T; Hesselinks, J W; Barkema, H W; Groen, A F

    2004-04-01

    This study was motivated by the hypothesis that the incidence of retained placenta (RP) in Friesian horses is associated with inbreeding. The objectives were to 1) calculate the inbreeding rate in the total registered Friesian horse population; 2) study the association of the inbreeding coefficient of the foal and the mare with the incidence of RP; and 3) study the heritability of RP in Friesian mares after normal foalings. Data from the total registered Friesian horse population from 1879 to 2000 (52,392 individuals) were collected from the registration files of the Friesian Horse Studbook. In 1999 and 2000, 495 parturitions in 436 mares were studied. From 1979 to 2000, the inbreeding rate of the total population was 1.9% per generation. The regression coefficients for the regression of the incidence of RP on inbreeding coefficients of the foal and the mare were 0.12 +/- 0.052 and -0.016 +/- 0.019, respectively. Mean heritability estimates of RP as a foal trait and as a mare trait were 0.046 +/- 0.088 and 0.105 +/- 0.123, respectively. It was concluded that, in order to avoid a further increase in the incidence of RP in Friesian mares, a decrease in the inbreeding rate by increasing the effective breeding population is required. Furthermore, the findings indicate that the high incidence of RP in Friesian horses is at least partly a result of inbreeding.

  6. THEORETICAL ANALYSIS OF USING AIRFLOW TO PURGE RESIDUAL WATER IN AN INCLINED PIPE

    Institute of Scientific and Technical Information of China (English)

    SHEN Fang(沈芳); YAN Zong-yi(严宗毅); ZHAO Yao-hua(赵耀华); Kiyoshi Horii

    2002-01-01

    A refined theoretical analysis for using the spiral airflow and axial airflow to purge residual water in an inclined pipe was presented. The computations reveal that, in most cases, the spiral flow can purge the residual water in the inclined pipe indeed while the axial flow may induce back flow of the water, just as predicted in the experiments presented by Horii and Zhao et al. In addition, the effects of various initial conditions on water purging were studied in detail for both the spiral and axial flow cases.

  7. [A variance-covariance model for analysis of pedigrees with inbreeding].

    Science.gov (United States)

    Svishcheva, G R

    2007-08-01

    A variance-covariance model is suggested for plotting the distribution of a quantitative trait analyzed in animal pedigrees resulting from crosses of outbred lines. The model takes inbreeding into account. A special parameter characterizing the degree of inbreeding has been introduced, which makes the model versatile. Pedigrees with the same structure that contain or not contain inbred individuals have been compared to analyze the effect of inbreeding on the parameters of the trait distribution, such as the mean genotypic value and variance of the trait.

  8. Habitat fragmentation, climate change, and inbreeding in plants.

    Science.gov (United States)

    Leimu, Roosa; Vergeer, Philippine; Angeloni, Francesco; Ouborg, N Joop

    2010-05-01

    Habitat fragmentation and climate change are recognized as major threats to biodiversity. The major challenge for present day plant populations is how to adapt and cope with altered abiotic and biotic environments caused by climate change, when at the same time adaptive and evolutionary potential is decreased as habitat fragmentation reduces genetic variation and increases inbreeding. Although the ecological and evolutionary effects of fragmentation and climate change have been investigated separately, their combined effects remained largely unexplored. In this review, we will discuss the individual and joint effects of habitat fragmentation and climate change on plants and how the abilities and ways in which plants can respond and cope with climate change may be compromised due to habitat fragmentation.

  9. Recent breeding history of dog breeds in Sweden: modest rates of inbreeding, extensive loss of genetic diversity and lack of correlation between inbreeding and health.

    Science.gov (United States)

    Jansson, M; Laikre, L

    2014-04-01

    One problem in modern dogs is a high occurrence of physical diseases, defects and disorders. Many breeds exhibit physical problems that affect individual dogs throughout life. A potential cause of these problems is inbreeding that is known to reduce the viability of individuals. We investigated the possible correlation between recent inbreeding and health problems in dogs and used studbook data from 26 breeds provided by the Swedish Kennel Club for this purpose. The pedigrees date back to the mid-20th century and comprise 5-10 generations and 1 000-50 000 individuals per pedigree over our study period of 1980-2010. We compared levels of inbreeding and loss of genetic variation measured in relation to the number of founding animals during this period in the investigated dog breeds that we classified as 'healthy' (11 breeds) or 'unhealthy' (15) based on statistics on the extent of veterinary care obtained from Sweden's four largest insurance companies for pets. We found extensive loss of genetic variation and moderate levels of recent inbreeding in all breeds examined, but no strong indication of a difference in these parameters between healthy versus unhealthy breeds over this period. Thus, recent breeding history with respect to rate of inbreeding does not appear to be a main cause of poor health in the investigated dog breeds in Sweden. We identified both strengths and weaknesses of the dog pedigree data important to consider in future work of monitoring and conserving genetic diversity of dog breeds.

  10. Purge gas protected transportable pressurized fuel cell modules and their operation in a power plant

    Science.gov (United States)

    Zafred, Paolo R.; Dederer, Jeffrey T.; Gillett, James E.; Basel, Richard A.; Antenucci, Annette B.

    1996-01-01

    A fuel cell generator apparatus and method of its operation involves: passing pressurized oxidant gas, (O) and pressurized fuel gas, (F), into fuel cell modules, (10 and 12), containing fuel cells, where the modules are each enclosed by a module housing (18), surrounded by an axially elongated pressure vessel (64), where there is a purge gas volume, (62), between the module housing and pressure vessel; passing pressurized purge gas, (P), through the purge gas volume, (62), to dilute any unreacted fuel gas from the modules; and passing exhaust gas, (82), and circulated purge gas and any unreacted fuel gas out of the pressure vessel; where the fuel cell generator apparatus is transpatable when the pressure vessel (64) is horizontally disposed, providing a low center of gravity.

  11. Purge and trap method to determine alpha factors of VOC liquid-phase mass transfer coefficients

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A theoretical approach and laboratory practice of determining the alpha factors of volatile organic compound (VOC) liquid-phase mass transfer coefficients are present in this study.Using Purge Trap Concentrator, VOC spiked water samples are purged by high-purity nitrogen in the laboratory, the VOC liquid-phase mass transfer rate constants under the laboratory conditions are then obtained by observing the variation of VOCs purged out of the water with the purge time.The alpha factors of VOC liquid-phase mass transfer coefficients are calculated as the ratios of the liquid-phase mass transfer rate constants in real water samples to their counterparts in pure water under the same experimental conditions. This direct and fast approach is easy to control in the laboratory, and would benefit mutual comparison among researchers, so might be useful for thestudy of VOC mass transfer across the liquid-gas interface.

  12. Validated Test Method 5030C: Purge-and-Trap for Aqueous Samples

    Science.gov (United States)

    This method describes a purge-and-trap procedure for the analysis of volatile organic compoundsin aqueous samples & water miscible liquid samples. It also describes the analysis of high concentration soil and waste sample extracts prepared in Method 5035.

  13. Metabolomic Signatures of Inbreeding at Benign and Stressful Temperatures in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Pedersen, Kamilla Sofie; Kristensen, Torsten Nygård; Loeschcke, Volker

    2008-01-01

    at the benign temperature was related to gene expression data from the same inbred and outbred lines. Both gene expression and metabolite data indicate that fundamental metabolic processes are changed or modified by inbreeding. Apart from affecting mean metabolite levels, inbreeding led to an increased between...... and five inbred lines were studied by nuclear magnetic resonance spectroscopy after exposure to benign temperature, heat stress, or cold stress. In both the absence and the presence of temperature stress, metabolite levels were significantly different among inbred and outbred lines. The major effect......-line variation in metabolite profiles compared to outbred lines. In contrast to previous observations revealing interactions between inbreeding and environmental stress on gene expression patterns and life-history traits, the effect of inbreeding on the metabolite profile was similar across the different...

  14. Effect of nitrogen crossover on purging strategy in PEM fuel cell systems

    DEFF Research Database (Denmark)

    Rabbani, Raja Abid; Rokni, Masoud

    2013-01-01

    conditions, making it important to investigate the dynamic performance of the system during transitory conditions. The model developed here is able to predict nitrogen crossover in excellent agreement with the design validation data of the stack. The results show that with pure recirculation, voltage...... levels from rising when compared to a fixed purge interval strategy. This model can be used as a base for control and development of anode purge strategies for automotive fuel cell systems....

  15. Effect of the extent of well purging on laboratory parameters of groundwater samples

    Science.gov (United States)

    Reka Mathe, Agnes; Kohler, Artur; Kovacs, Jozsef

    2017-04-01

    Chemicals reaching groundwater cause water quality deterioration. Reconnaissance and remediation demands high financial and human resources. Groundwater samples are important sources of information. Representativity of these samples is fundamental to decision making. According to relevant literature the way of sampling and the sampling equipment can affect laboratory concentrations measured in samples. Detailed and systematic research on this field is missing from even international literature. Groundwater sampling procedures are regulated worldwide. Regulations describe how to sample a groundwater monitoring well. The most common element in these regulations is well purging prior to sampling. The aim of purging the well is to avoid taking the sample from the stagnant water instead of from formation water. The stagnant water forms inside and around the well because the well casing provides direct contact with the atmosphere, changing the physico-chemical composition of the well water. Sample from the stagnant water is not representative of the formation water. Regulations regarding the extent of the purging are different. Purging is mostly defined as multiply (3-5) well volumes, and/or reaching stabilization of some purged water parameters (pH, specific conductivity, etc.). There are hints for sampling without purging. To define the necessary extent of the purging repeated pumping is conducted, triplicate samples are taken at the beginning of purging, at one, two and three times well volumes and at parameter stabilization. Triplicate samples are the means to account for laboratory errors. The subsurface is not static, the test is repeated 10 times. Up to now three tests were completed.

  16. Regimes of Decomposition of Clathrate in Natural Strata Purged by Methane

    Science.gov (United States)

    Khasanov, M.; Shagapov, V.

    2016-06-01

    The process of decomposition of a methane clathrate in a finite-length stratum initially saturated with methane clathrate and methane, which is purged by warm methane, is studied. The influence of the initial parameters of the stratum and purging conditions on the evolution of methane clathrate temperature and saturation is examined. The existence of solutions is demonstrated, which predict methane clathrate decomposition both on the frontal surface and in the volume zone.

  17. The Self-Regulation Effect of Fertility Status on Inbreeding Aversion: When Fertile, Disgust Increases more in Response to Descriptions of One's Own than of Others' Inbreeding

    Directory of Open Access Journals (Sweden)

    Jan Antfolk

    2014-07-01

    Full Text Available The ovulatory shift modulates emotions related to female sexuality. Because fertility status only affects the individual's own opportunity cost, the adaptive value of this shift is expected to stem from self-regulation. To test this assumption we asked women to contemplate various inbreeding descriptions: 1 they themselves having sex with male relatives; 2 their sister having sex with their common male relatives; and 3 an unrelated woman having sex with her male relatives (in 1, but not 2 and 3, negative fitness consequences are affected by the participant's fertility. We dichotomized the dependent variable disgust (ceiling vs. non-ceiling and analyzed the interaction between fertility status and description type. The ovulatory shift was stronger in descriptions where they themselves were described as engaging in inbreeding. A smaller increase was also found in reactions to others engaging in inbreeding. We explain the latter effect as due to self-reflection.

  18. [Purging behaviors and nutritional status in anorexia nervosa and bulimia nervosa].

    Science.gov (United States)

    Vaz, F J; García-Herráiz, A; López-Vinuesa, B; Monge, M; Fernández-Gil, M A; Guisado, J A

    2003-01-01

    The aim of the study was to investigate whether the use of purgative methods in patients with eating disorders (anorexia nervosa [AN] and bulimia nervosa [BN]) could be capable of producing changes in the nutritional status of the patients. The group under study was composed of 184 female eating disordered outpatients. One hundred and sixteen patients (63.0%) fulfilled the DSM-IV diagnostic criteria for BN (90 purging type, 26 nonpurging type). Sixty eight patients (37.0%) fulfilled the DSM-IV criteria for the diagnosis of AN (48 restricting type, 20 binging-purging type). The assessment process included anthropometry (body circumferences and skinfold thickness) and body impedance analysis. The two subgroups of AN patients significantly differed from each of the BN subgroups. From a nutritional point of view, some significant differences between the two DSM-IV subtypes of AN existed, but not between the purging type and the nonpurging type of BN. The paper discusses the clinical significance of these findings. An alternative subtypification of AN patients is proposed: 1) restricting type [patients who control their food intake and do not purge]; 2) purging type [patient with true episodes of binging which are followed by purgative behaviors]; and 3) pseudopurging type [patients with subjective binging episodes who use purging methods].

  19. Estimates of inbreeding and relationship among registered Holstein females in the United States.

    Science.gov (United States)

    Young, C W; Seykora, A J

    1996-03-01

    The estimate of inbreeding for registered Holstein females born during 1990 was 5.1 +/- 0.4% for a random sample of 600 two-line pedigrees. Previously published estimates were 4.7% for 1970, 3.8% for 1976, and 4.3% for 1982 from similar samples of pedigrees. These estimates were calculated using a base of approximately 1884, or the initiation of herd-book registration in the US. The estimate of relationship between randomly paired females born during 1990 was 10.2 +/- 0.8%; relationships were 5.2% for 1970, 7.3% for 1976, and 9.8% for 1982. Average relationship within the breed increased significantly without a corresponding increase in inbreeding. Inbreeding was also estimated for alternative base years with 10-yr increments to determine the effect of base year on estimates of inbreeding. Using 1950 as the base year, inbreeding was estimated at 0.5% for 1970, 0.3% for 1976, 1.6% for 1982, and 2.1% for 1990. Estimates using 1920 as the base year were 2.0% for 1970, 1.9% for 1976, 2.3% for 1982, and 3.2% for 1990. More recent base years gave lower estimates of inbreeding, as expected, but showed an exaggerated percentage of increase in inbreeding from 1970 to 1990. However, the annual amount of increase of inbreeding from 1976 to 1990 was not significantly affected by time of base year and ranged from 0.08 to 0.12/yr. The five most influential bulls of the breed were Pawnee Farm Arlinda Chief 1427381, Round Oak Rag Apple Elevation 1491007, S-W-D Valiant 1650414, Osborndale Ivanhoe 1189870, and Sir Pietertje Ormsby Mercedes 44931; estimated direct relationships to the breed were 0.123, 0.122, 0.096, 0.083, and 0.074, respectively.

  20. Anode purge strategy optimization of the polymer electrode membrane fuel cell system under the dead-end anode operation

    Science.gov (United States)

    Hu, Zhe; Yu, Yi; Wang, Guangjin; Chen, Xuesong; Chen, Pei; Chen, Jun; Zhou, Su

    2016-07-01

    Dead-ended anode (DEA) mode is commonly applied in fuel cell vehicles for the hydrogen purge at the anode side, to reduce fuel waste and enhance fuel cell efficiency. Anode purge is necessary and is definitely important with respect to removing liquid water and accumulated nitrogen in the gas diffusion layer and the flow field of the DEA-mode fuel cell. In this paper, the effect of different purge strategies on the stack performance and system efficiency is investigated experimentally using fast data acquisition and advanced tools, such as the fast cell voltage measurement (CVM) system and the mass spectrum. From the fast data acquisition, the voltage stability, liquid water and nitrogen concentration measurement in the anode exhaust are compared and analyzed under different purge strategy designs and using different purge valves. The results show that under the optimal purge strategy, the DEA fuel cell stack can achieve the desired stability and system efficiency based on the analysis of the cell voltage and purge volume. Moreover, the diameter of the purge valve has a great impact on the voltage stability because a diameter change will result in a different pressure drop and purge volume when the purge valve is open.

  1. Inbreeding and Offspring Sex Ratio in the Pygmy Hippopotamus (Cheoropsis liberiensis) Population Kept in Zoological Gardens.

    Science.gov (United States)

    Graczyk, Magdalena; Cwiertnia, Piotr; Borowska, Alicja; Barczak, Elżbieta; Szwaczkowski, Tomasz

    2015-01-01

    The aim of this study was to estimate the inbreeding level and its impact on offspring sex ratio in the pygmy hippopotamus population kept in zoological gardens. Records of pygmy hippopotamus born between 1873-2013 were extracted from the international studbook. Totally, 1357 individuals originating from 148 breeding units were included (individuals with unknown sex were omitted). The offspring sex ratio is defined as the number of sons to the total number of progeny of each dam and sire. Spearman's rank correlation was employed to examine the relationships between the inbreeding level and offspring sex ratio. Inbreeding coefficients and individual increase in inbreeding coefficients (included as a linear co-variable) were examined as well as the geographic region and birth period using general linear models. The average inbreeding coefficient was 5.39%. The following sex proportion was observed for the inbred population: 57% and 43% for females and males, respectively. A significant relationship between inbreeding level of parents and their offspring sex ratio were estimated for European zoological gardens, whereas in others geographic regions the dependencies were insignificant.

  2. Assessment of inbreeding resulting from selection for scrapie resistance: a model for rare sheep breeds.

    Science.gov (United States)

    Brown, C; Orford, M; Tzamaloukas, O; Mavrogenis, A P; Miltiadou, D

    Inbreeding in a small population of Chios sheep undergoing intense selection for the PrP gene was assessed 10 years after the beginning of a scrapie resistance selection programme. Inbreeding in this stock, already under selection for production traits, was analysed by using pedigree records containing 10,492 animals from 1968 to 2008, and also by genotyping 192 individuals with a panel of 15 microsatellites. Genetic markers indicated a loss of heterozygosity (FIS over all loci was 0.059) and allelic diversity (mean effective number of alleles was 3.075±0.275). The annual rate of inbreeding increased significantly after the start of the scrapie resistance programme, ΔF=0.005 compared with ΔF=0.001 before 1999, and was subjected to several genetic bottlenecks, mainly due to the low initial frequency of resistant animals. However, the mean individual inbreeding coefficient estimated from the pedigree - in this closed stock resembling the case of a rare breed - stood at the level of 4.5 per cent, five generations after the implementation of selection for the PrP gene. The inbreeding coefficient estimated by genetic markers was 4.37 per cent, implying that such a marker panel could be a useful and cost-effective tool for estimating inbreeding in unrecorded populations.

  3. The effect of fast created inbreeding on litter size and body weights in mice

    Directory of Open Access Journals (Sweden)

    Meuwissen Theo

    2005-09-01

    Full Text Available Abstract This study was designed to reveal any differences in effects of fast created versus total inbreeding on reproduction and body weights in mice. A line selected for large litter size for 124 generations (H and a control line (K maintained without selection for the same number of generations were crossed (HK and used as a basis for the experiment. Within the HK cross, full sib, cousin or random mating were practised for two generations in order to create new inbreeding (IBF at a fast rate. In the first generation of systematic mating, old inbreeding was regenerated in addition to creation of new inbreeding from the mating design giving total inbreeding (IBT. The number of pups born alive (NBA and body weights of the animals were then analysed by a model including both IBT and IBF. The IBT of the dam was in the present study found to reduce the mean NBA with -0.48 (± 0.22 (p F was -0.42 (± 0.27. For the trait NBA per female mated, the effect of IBT was estimated to be -0.45 (± 0.29 per 10% increase in the inbreeding coefficient and the effect of IBF was -0.90 (± 0.37 (p F of the dam could be found on sex-ratio and body weights at three and six weeks of age in a population already adjusted for IBT.

  4. Inbreeding and its Effect on Performance Traits in Austrian Meat Sheep

    Directory of Open Access Journals (Sweden)

    Lina Maximini

    2011-10-01

    Full Text Available The aim of this study was to evaluate the level of inbreeding of meat performance tested herd book sheep in Austria and to evaluate the effect of individual inbreeding on growth and CT (computer tomography scan carcass traits. Performance data (13,614 records, five breeds: Merinoland, Suff olk, Texel, German Blackheaded Meat sheep, Jura were collected in the years 2000-2010. The traits analysed were live weight and average daily gain, as well as traits of body frame, back fat and eye muscle area, all measured on live animals with CT. Inbreeding coefficients (F were calculated with the soft ware PEDIG. F was nested within breed and tested in a mixed model using ASReml. Levels of inbreeding were low with O F of 1.5-3.1%. Only few traits were significantly affected by inbreeding. Both positive and negative effects were found. The effects were small, most oft en nonlinear and vary across breeds. Inbreeding and its effects on performance traits do not seem to be an issue in Austrian meat sheep populations at the moment. However, monitoring and further analyses are recommended.

  5. Inbreeding and its Effect on Performance Traits in Austrian Meat Sheep

    Directory of Open Access Journals (Sweden)

    Lina Maximini

    2011-09-01

    Full Text Available The aim of this study was to evaluate the level of inbreeding of meat performance tested herd book sheep in Austria and to evaluate the effect of individual inbreeding on growth and CT (computer tomography scan carcass traits. Performance data (13,614 records, five breeds: Merinoland, Suff olk, Texel, German Blackheaded Meat sheep, Jura were collected in the years 2000-2010. The traits analysed were live weight and average daily gain, as well as traits of body frame, back fat and eye muscle area, all measured on live animals with CT. Inbreeding coefficients (F were calculated with the soft ware PEDIG. F was nested within breed and tested in a mixed model using ASReml. Levels of inbreeding were low with O F of 1.5-3.1%. Only few traits were significantly affected by inbreeding. Both positive and negative effects were found. The effects were small, most oft en nonlinear and vary across breeds. Inbreeding and its effects on performance traits do not seem to be an issue in Austrian meat sheep populations at the moment. However, monitoring and further analyses are recommended.

  6. EFFECT OF INBREEDING ON PRE-WEANING GROWTH TRAITS IN THALLI SHEEP

    Directory of Open Access Journals (Sweden)

    A. HUSSAIN, P. AKHTAR, S. ALI, M. YOUNAS1 AND M. SHAFIQ2

    2006-07-01

    Full Text Available Pedigree records of 17250 Thalli sheep with 17030 lambings maintained at the Livestock Experiment Station, Rakh Ghulaman, Distt. Bhakkar, Pakistan during the period from 1975 to 2004 were utilized in the present study. Average values for birth weight, weights at 60 and 90 days of age, weaning weight and pre-weaning average daily gain were 4.11 ± 0.82, 11.58 ± 3.57, 14.92 ± 4.56, 18.95 ± 4.56 and 0.12 ± 0.04 kg, respectively. Coefficients of inbreeding ranged from 10.15 to 37.50 percent for 295 animals, being 1.70 percent of the flock. Inbreeding significantly (P<0.01 affected birth and 60 days weight. Birth weight and 60 days weight decreased by 0.051 and 0.048 kg for each 1 percent increase in the level of inbreeding. However, inbreeding had non significant effect on weight at 90 days of age, weaning weight and pre-weaning average daily gain. The regression values for these traits were 0.010, 0.083 and 0.105, respectively. It was concluded that inbreeding showed deleterious effects only in early stages of life but as the lambs grew older the effect of inbreeding on pre-weaning traits diminished.

  7. Distinguishing Between Risk Factors for Bulimia Nervosa, Binge Eating Disorder, and Purging Disorder.

    Science.gov (United States)

    Allen, Karina L; Byrne, Susan M; Crosby, Ross D

    2015-08-01

    Binge eating disorder and purging disorder have gained recognition as distinct eating disorder diagnoses, but risk factors for these conditions have not yet been established. This study aimed to evaluate a prospective, mediational model of risk for the full range of binge eating and purging eating disorders, with attention to possible diagnostic differences. Specific aims were to determine, first, whether eating, weight and shape concerns at age 14 would mediate the relationship between parent-perceived childhood overweight at age 10 and a binge eating or purging eating disorder between age 15 and 20, and, second, whether this mediational model would differ across bulimia nervosa, binge eating disorder, and purging disorder. Participants (N = 1,160; 51 % female) were drawn from the Western Australian Pregnancy Cohort (Raine) Study, which has followed children from pre-birth to age 20. Eating disorders were assessed via self-report questionnaires when participants were aged 14, 17 and 20. There were 146 participants (82 % female) with a binge eating or purging eating disorder with onset between age 15 and 20 [bulimia nervosa = 81 (86 % female), binge eating disorder = 43 (74 % female), purging disorder = 22 (77 % female)]. Simple mediation analysis with bootstrapping was used to test the hypothesized model of risk, with early adolescent eating, weight and shape concerns positioned as a mediator between parent-perceived childhood overweight and later onset of a binge eating or purging eating disorder. Subsequently, a conditional process model (a moderated mediation model) was specified to determine if model pathways differed significantly by eating disorder diagnosis. In the simple mediation model, there was a significant indirect effect of parent-perceived childhood overweight on risk for a binge eating or purging eating disorder in late adolescence, mediated by eating, weight and shape concerns in early adolescence. In the conditional process model

  8. A novel surgical strategy for secondary hyperparathyroidism: Purge parathyroidectomy.

    Science.gov (United States)

    Shan, Cheng-Xiang; Qiu, Nian-Cun; Zha, Si-Luo; Liu, Miao-E; Wang, Qiang; Zhu, Pei-Pei; Du, Zhi-Peng; Xia, Chun-Yan; Qiu, Ming; Zhang, Wei

    2017-07-01

    This study was intended to demonstrate the feasibility and efficacy of purge parathyroidectomy (PPTX) for patients with secondary hyperparathyroidism (SHPT). The "seed, environment, and soil" medical hypothesis was first raised, following review of the literatures, to demonstrate the possible causes of persistence or recurrence of SHPT after parathyroidectomy. Subsequently, the novel surgical strategy of PPTX was proposed, which involves comprehensive resection of the fibro-fatty tissues, including visible or invisible parathyroid, within the region surrounded by the thyroid cartilage, bilateral carotid artery sheath, and the brachiocephalic artery. The perioperative information and clinical outcomes of patients who underwent PPTX from June 2016 to December 2016 were analyzed. In total, PPTX was performed safely in nine patients with SHPT from June 2016 to December 2016. The operative time for PPTX ranged from 95 to 135 min, and blood loss ranged from 20 to 40 mL. No patients with perioperative death, bleeding, convulsions, or recurrent laryngeal nerve injury were reported. The preoperative concentration of PTH ranged from 1062 to 2879 pg/mL, and from 12.35 to 72.69 pg/mL on the first day after surgery. In total, 37 parathyroid glands were resected. The postoperative pathologic examination showed that supernumerary or ectopic parathyroid tissues were found within the "non-parathyroid" tissues in three patients. No cases encountered persistence or recurrence of SHPT, or severe hypocalcemia during the follow-up period. PPTX involves comprehensive resection of supernumerary and ectopic parathyroid tissues, which may provide a more permanent means of reducing PTH levels. Copyright © 2017. Published by Elsevier Ltd.

  9. Preparation and analysis of helium purge gas mixture to be used in Tritium Extraction System of LLCB TBM

    Science.gov (United States)

    Gayathri Devi, V.; Yadav, Deepak; Sircar, Amit

    2017-04-01

    Hydrogen isotopes are extracted from the Ceramic Breeder (CB) and liquid Lead Lithium (Pb-Li) breeder of Lead Lithium Ceramic Breeder (LLCB) Test Blanket Module (TBM) with Helium purge gas. 1000 ppm of hydrogen gas is mixed with the purge helium gas to facilitate improved extraction of hydrogen isotopes from the breeder zones by hydrogen swamping reactions [1]. An experimental set up is developed for making up the purge gas mixture with a composition similar to the purge gas composition to be used for extraction of hydrogen isotopes from CB and Pb-Li of LLCB TBM. This is achieved by introducing different ppm levels (1000 - 5000 ppm) of hydrogen in helium gas by flow control mechanism. The analysis of the purge gas mixture is performed using a highly sensitive Gas Chromatography (GC) system. This paper describes the detailed design of the experimental set-up and results for the analysis of different concentrations of hydrogen in helium purge gas.

  10. Genome-wide estimates of coancestry, inbreeding and effective population size in the Spanish Holstein population.

    Directory of Open Access Journals (Sweden)

    Silvia Teresa Rodríguez-Ramilo

    Full Text Available Estimates of effective population size in the Holstein cattle breed have usually been low despite the large number of animals that constitute this breed. Effective population size is inversely related to the rates at which coancestry and inbreeding increase and these rates have been high as a consequence of intense and accurate selection. Traditionally, coancestry and inbreeding coefficients have been calculated from pedigree data. However, the development of genome-wide single nucleotide polymorphisms has increased the interest of calculating these coefficients from molecular data in order to improve their accuracy. In this study, genomic estimates of coancestry, inbreeding and effective population size were obtained in the Spanish Holstein population and then compared with pedigree-based estimates. A total of 11,135 animals genotyped with the Illumina BovineSNP50 BeadChip were available for the study. After applying filtering criteria, the final genomic dataset included 36,693 autosomal SNPs and 10,569 animals. Pedigree data from those genotyped animals included 31,203 animals. These individuals represented only the last five generations in order to homogenise the amount of pedigree information across animals. Genomic estimates of coancestry and inbreeding were obtained from identity by descent segments (coancestry or runs of homozygosity (inbreeding. The results indicate that the percentage of variance of pedigree-based coancestry estimates explained by genomic coancestry estimates was higher than that for inbreeding. Estimates of effective population size obtained from genome-wide and pedigree information were consistent and ranged from about 66 to 79. These low values emphasize the need of controlling the rate of increase of coancestry and inbreeding in Holstein selection programmes.

  11. Genome-wide estimates of coancestry, inbreeding and effective population size in the Spanish Holstein population.

    Science.gov (United States)

    Rodríguez-Ramilo, Silvia Teresa; Fernández, Jesús; Toro, Miguel Angel; Hernández, Delfino; Villanueva, Beatriz

    2015-01-01

    Estimates of effective population size in the Holstein cattle breed have usually been low despite the large number of animals that constitute this breed. Effective population size is inversely related to the rates at which coancestry and inbreeding increase and these rates have been high as a consequence of intense and accurate selection. Traditionally, coancestry and inbreeding coefficients have been calculated from pedigree data. However, the development of genome-wide single nucleotide polymorphisms has increased the interest of calculating these coefficients from molecular data in order to improve their accuracy. In this study, genomic estimates of coancestry, inbreeding and effective population size were obtained in the Spanish Holstein population and then compared with pedigree-based estimates. A total of 11,135 animals genotyped with the Illumina BovineSNP50 BeadChip were available for the study. After applying filtering criteria, the final genomic dataset included 36,693 autosomal SNPs and 10,569 animals. Pedigree data from those genotyped animals included 31,203 animals. These individuals represented only the last five generations in order to homogenise the amount of pedigree information across animals. Genomic estimates of coancestry and inbreeding were obtained from identity by descent segments (coancestry) or runs of homozygosity (inbreeding). The results indicate that the percentage of variance of pedigree-based coancestry estimates explained by genomic coancestry estimates was higher than that for inbreeding. Estimates of effective population size obtained from genome-wide and pedigree information were consistent and ranged from about 66 to 79. These low values emphasize the need of controlling the rate of increase of coancestry and inbreeding in Holstein selection programmes.

  12. Male inbreeding status affects female fitness in a seed-feeding beetle.

    Science.gov (United States)

    Fox, Charles W; Xu, J; Wallin, W G; Curtis, C L

    2012-01-01

    Inbreeding generally reduces male mating activity such that inbred males are less successful in male-male competition. Inbred males can also have smaller accessory glands, transfer less sperm and produce sperm that are less motile, less viable or have a greater frequency of abnormalities, all of which can reduce the fertilization success and fitness of inbred males relative to outbred males. However, few studies have examined how male inbreeding status affects the fitness of females with whom they mate. In this study, we examine the effect of male inbreeding status (inbreeding coefficient f = 0.25 vs. f = 0) on the fecundity, adult longevity and the fate of eggs produced by outbred females in the seed-feeding beetle, Callosobruchus maculatus. Females mated to inbred males were less likely to lay eggs. Of those that laid eggs, females mated to inbred males laid 6-12% fewer eggs. Females mated to inbred males lived on average 5.4% longer than did females mated to outbred males, but this effect disappeared when lifetime fecundity was used as a covariate in the analysis. There was no effect of male inbreeding status on the proportion of a female's eggs that developed or hatched, and no evidence that inbred males produced smaller nuptial gifts. However, ejaculates of inbred males contained 17-33% fewer sperm, on average, than did ejaculates of outbred males. Our study demonstrates that mating with inbred males has significant direct consequences for the fitness of female C. maculatus, likely mediated by effects of inbreeding status on the number of sperm in male ejaculates. Direct effects of male inbreeding status on female fitness should be more widely considered in theoretical models and empirical studies of mate choice.

  13. Depression (Major Depressive Disorder)

    Science.gov (United States)

    ... generally miserable or unhappy without really knowing why. Depression symptoms in children and teens Common signs and ... in normal activities, and avoidance of social interaction. Depression symptoms in older adults Depression is not a ...

  14. Variability in bacteria and virus-like particle abundances during purging of unconfined aquifers.

    Science.gov (United States)

    Roudnew, Ben; Lavery, Trish J; Seymour, Justin R; Jeffries, Thomas C; Mitchell, James G

    2014-01-01

    Standard methodologies for sampling the physicochemical conditions of groundwater recommend purging a bore for three bore volumes to avoid sampling the stagnant water within a bore and instead gain samples representative of the aquifer. However, there are currently no methodological standards addressing the amount of purging required to gain representative biological samples to assess groundwater bacterial and viral abundances. The objective of this study was to examine how bacterial and viral abundances change during the purging of bore volumes. Six bores infiltrating into unconfined aquifers were pumped for five or six bore volumes each and bacteria and virus-like particles (VLPs) were enumerated from each bore volume using flow cytometry. In examination of the individual bores trends in bacterial abundances were observed to increase, decrease, or remain constant with each purged bore volume. Furthermore, triplicates taken at each bore volume indicated substantial variations in VLP and bacterial abundances that are often larger than the differences between bore volumes. This indicates a high level of small scale heterogeneity in microbial community abundance in groundwater samples, and we suggest that this may be an intrinsic feature of bore biology. The heterogeneity observed may be driven by bottom up processes (variability in the distribution of organic and inorganic nutrients), top-down processes (grazing and viral lysis), physical heterogeneities in the bore, or technical artifacts associated with the purging process. We suggest that a more detailed understanding of the ecology underpinning this variability is required to adequately describe the microbiological characteristics of groundwater ecosystems.

  15. The Initial Purging Policies after the 1965 Incident at Lubang Buaya

    Directory of Open Access Journals (Sweden)

    Yosef Djakababa

    2013-01-01

    Full Text Available After the Lubang Buaya incident on 1 October 1965 in which six top Indonesian Army generals and a lieutenant were killed, the Army began to implement a nationwide purging campaign with the assistance of civilian anti-communist groups. Thousands of PKI members, supporters and pro-Sukarno groups/individuals immediately became the target of this purge. For organisational purposes, several purging policies were released and then strictly enforced. The official purging policies that are highlighted in this paper are a series of initial directives that were released within days of the generals’ executions. They do not explicitly translate into orders to kill, but are more of a guideline to help anti-communist officials classify and contain communists and other PKI followers. This article attempts to show how these initial directives evolved and also discusses competing purge policies from non-military sources. The co-existence and overlapping nature of the various directives indicate that a power struggle existed between the anti-communist group led by General Soeharto and the presidium of the Dwikora Cabinet who were loyal to President Soekarno.

  16. Marker-assisted selection can reduce true as well as pedigree-estimated inbreeding.

    Science.gov (United States)

    Pedersen, L D; Sørensen, A C; Berg, P

    2009-05-01

    This study investigated whether selection using genotype information reduced the rate and level of true inbreeding, that is, identity by descent, at a selectively neutral locus as well as a locus under selection compared with traditional BLUP selection. In addition, the founder representation at these loci and the within-family selection at the nonneutral locus were studied. The study was carried out using stochastic simulation of a population resembling the breeding nucleus of a dairy cattle population for 25 yr. Each year, 10 proven bulls were selected across herds along with 100 dams from within each of 40 herds. Selection was performed using BLUP, marker-assisted, or gene-assisted selection for a trait with low heritability (h2 = 0.04) only expressed in females, mimicking a health trait. The simulated genome consisted of 2 chromosomes. One biallelic quantitative trait loci (QTL) with an initial frequency of the favorable allele of 0.1, and initially explaining 25% of the genetic variance as well as 4 markers were simulated in linkage disequilibrium, all positioned at chromosome 1. Chromosome 2 was selectively neutral, and consisted of a single neutral locus. The results showed that in addition to reducing pedigree-estimated inbreeding, the incorporation of genotype information in the selection criteria also reduced the level and rate of true inbreeding. In general, true inbreeding in the QTL was greater than pedigree-estimated inbreeding with respect to both the level and rate of inbreeding, as expected. Also as expected, true and pedigree-estimated inbreeding in the neutral locus were the same. Furthermore, after 25 yr, or approximately 5 generations, the pedigree-estimated level of inbreeding was reduced by 11 and 24% compared with BLUP in gene- and marker-assisted selection, respectively, and the level of true inbreeding in the QTL was reduced by 22 and 13%, respectively. The difference between selection scenarios was found to be caused by a larger number of

  17. A recursive method for computing expected kinship and inbreeding in complex and dynamic breeding programmes.

    Science.gov (United States)

    Sitzenstock, F; Ytournel, F; Simianer, H

    2013-02-01

    In many livestock breeding programmes, the development of inbreeding is of critical importance. Thus, the assessment of the expected development of inbreeding should be an essential element in the design of breeding programmes. We propose a new method to deterministically predict the rate of inbreeding based on the gene-flow method in well-defined complex and dynamic breeding programmes. In the suggested approach, a breeding programme has to be structured in homogeneous age-sex-groups, so called cohorts, with a defined origin of genes. Starting from an initial setup (usually an unrelated and non-inbred base population), transition rules to calculate the kinship within and between cohorts originating from reproduction or ageing, respectively, are defined. Using this approach recursively provides the expected development of kinship within and between all cohorts over time, which can be combined into average kinships for the whole population or defined subsets. From these quantities, relevant parameters like the inbreeding rate or the effective population size are easily derived. We illustrate the method with a simple static example breeding programme in sheep. Based on this reference breeding programme, we demonstrate the use of our approach for dynamic breeding programmes, in which cohort sizes or vectors of gene origin change over time: here, we model the situation of exponential population growth and a bottleneck situation, respectively. The suggested approach does not account for the effect of selection on the development of inbreeding, but ideas to overcome this limitation are discussed.

  18. Quantitative genetics model as the unifying model for defining genomic relationship and inbreeding coefficient.

    Science.gov (United States)

    Wang, Chunkao; Da, Yang

    2014-01-01

    The traditional quantitative genetics model was used as the unifying approach to derive six existing and new definitions of genomic additive and dominance relationships. The theoretical differences of these definitions were in the assumptions of equal SNP effects (equivalent to across-SNP standardization), equal SNP variances (equivalent to within-SNP standardization), and expected or sample SNP additive and dominance variances. The six definitions of genomic additive and dominance relationships on average were consistent with the pedigree relationships, but had individual genomic specificity and large variations not observed from pedigree relationships. These large variations may allow finding least related genomes even within the same family for minimizing genomic relatedness among breeding individuals. The six definitions of genomic relationships generally had similar numerical results in genomic best linear unbiased predictions of additive effects (GBLUP) and similar genomic REML (GREML) estimates of additive heritability. Predicted SNP dominance effects and GREML estimates of dominance heritability were similar within definitions assuming equal SNP effects or within definitions assuming equal SNP variance, but had differences between these two groups of definitions. We proposed a new measure of genomic inbreeding coefficient based on parental genomic co-ancestry coefficient and genomic additive correlation as a genomic approach for predicting offspring inbreeding level. This genomic inbreeding coefficient had the highest correlation with pedigree inbreeding coefficient among the four methods evaluated for calculating genomic inbreeding coefficient in a Holstein sample and a swine sample.

  19. Local area water removal analysis of a proton exchange membrane fuel cell under gas purge conditions.

    Science.gov (United States)

    Lee, Chi-Yuan; Lee, Yu-Ming; Lee, Shuo-Jen

    2012-01-01

    In this study, local area water content distribution under various gas purging conditions are experimentally analyzed for the first time. The local high frequency resistance (HFR) is measured using novel micro sensors. The results reveal that the liquid water removal rate in a membrane electrode assembly (MEA) is non-uniform. In the under-the-channel area, the removal of liquid water is governed by both convective and diffusive flux of the through-plane drying. Thus, almost all of the liquid water is removed within 30 s of purging with gas. However, liquid water that is stored in the under-the-rib area is not easy to remove during 1 min of gas purging. Therefore, the re-hydration of the membrane by internal diffusive flux is faster than that in the under-the-channel area. Consequently, local fuel starvation and membrane degradation can degrade the performance of a fuel cell that is started from cold.

  20. A synthetic biochemistry molecular purge valve module that maintains redox balance.

    Science.gov (United States)

    Opgenorth, Paul H; Korman, Tyler P; Bowie, James U

    2014-06-17

    The greatest potential environmental benefit of metabolic engineering would be the production of high-volume commodity chemicals, such as biofuels. Yet, the high yields required for the economic viability of low-value chemicals is particularly hard to achieve in microbes owing to the myriad competing biochemical pathways. An alternative approach, which we call synthetic biochemistry, is to eliminate the organism by constructing biochemical pathways in vitro. Viable synthetic biochemistry, however, will require simple methods to replace the cellular circuitry that maintains cofactor balance. Here we design a simple purge valve module for maintaining NADP(+)/NADPH balance. We test the purge valve in the production of polyhydroxybutyryl bioplastic and isoprene--pathways where cofactor generation and utilization are unbalanced. We find that the regulatory system is highly robust to variations in cofactor levels and readily transportable. The molecular purge valve provides a step towards developing continuously operating, sustainable synthetic biochemistry systems.

  1. Purging using the Heimlich maneuver among children and adolescents with eating disorders.

    Science.gov (United States)

    Boachie, Ahmed; Kusi Appiah, Edigna; Jubin, Michelle; Jasper, Karin

    2015-09-01

    This case report describes five independent cases of children and adolescents assessed for eating disorders who disclosed using the Heimlich maneuver as a purging technique. The maneuver is meant to be used only in life or death situations, likely once or less in any person's lifetime. A child or adolescent with an eating disorder may be using it to self-induce vomiting on a daily basis, increasing the risk of complications, including potential damage to major organs of the body. Asking patients who purge to elaborate on the methods with which they purge can provide clinicians with fuller information, improving their ability to select appropriate medical tests and interventions. Thorough investigations of physical complaints during the patient assessment may be warranted, including examining patients for possible rib fractures, hemorrhages, perforations of the hollow viscous, and other forms of blunt abdominal traumas.

  2. Thinness and eating expectancies predict subsequent binge-eating and purging behavior among adolescent girls.

    Science.gov (United States)

    Smith, Gregory T; Simmons, Jean R; Flory, Kate; Annus, Agnes M; Hill, Kelly K

    2007-02-01

    One's expectancies for reinforcement from eating or from thinness are thought to represent summaries of one's eating-related learning history and to thus influence the development of binge-eating and purging behavior. In a 3-year longitudinal study, the authors tested this hypothesis and the hypothesis that binge eating also influences subsequent expectancy development. The authors used trajectory analysis to identify groups of middle school girls who followed different trajectories of binge eating, purging, eating expectancies, and thinness expectancies. Initial eating and thinness reinforcement expectancies identified girls whose binge eating and purging increased during middle school, and expectancies differentiated girls who began these problem behaviors from girls who did not. Initial binge-eating scores differentiated among eating expectancy developmental trajectories. The onset of most behaviors can be understood in terms of learned expectancies for reinforcement from these behaviors. The same model can be applied to the risk for eating disorders.

  3. Effect of the purging gas on properties of Ti stabilized AISI 321 stainless steel TIG welds

    Energy Technology Data Exchange (ETDEWEB)

    Taban, Emel; Kaluc, Erdinc; Aykan, T. Serkan [Kocaeli Univ. (Turkey). Dept. of Mechanical Engineering

    2014-07-01

    Gas purging is necessary to provide a high quality of stainless steel pipe welding in order to prevent oxidation of the weld zone inside the pipe. AISI 321 stabilized austenitic stainless steel pipes commonly preferred in refinery applications have been welded by the TIG welding process both with and without the use of purging gas. As purging gases, Ar, N{sub 2}, Ar + N{sub 2} and N{sub 2} + 10% H{sub 2} were used, respectively. The aim of this investigation is to detect the effect of purging gas on the weld joint properties such as microstructure, corrosion, strength and impact toughness. Macro sections and microstructures of the welds were investigated. Chemical composition analysis to obtain the nitrogen, oxygen and hydrogen content of the weld root was done by Leco analysis. Ferrite content of the beads including root and cap passes were measured by a ferritscope. Vickers hardness (HV10) values were obtained. Intergranular and pitting corrosion tests were applied to determine the corrosion resistance of all welds. Type of the purging gas affected pitting corrosion properties as well as the ferrite content and nitrogen, oxygen and hydrogen contents at the roots of the welds. Any hot cracking problems are not predicted as the weld still solidifies with ferrite in the primary phase as confirmed by microstructural and ferrite content analysis. Mechanical testing showed no significant change according to the purge gas. AISI 321 steel and 347 consumable compositions would permit use of nitrogen rich gases for root shielding without a risk of hot cracking.

  4. Colonic diverticular bleeding: urgent colonoscopy without purging and endoscopic treatment with epinephrine and hemoclips

    Directory of Open Access Journals (Sweden)

    Ignacio Couto-Worner

    2013-09-01

    Full Text Available Diverticular disease is the most frequent cause of lower gastrointestinal bleeding. Most of the times, bleeding stops without any intervention but in 10-20 % of the cases it is necessary to treat the hemorrhage. Several modalities of endoscopic treatment have been described after purging the colon. We present five cases of severe diverticular bleeding treated with injection of epinephrine and hemoclips. All the colonoscopies were performed without purging of the colon in an emergency setting, with correct visualization of the point of bleeding. Patients recovered well avoiding other aggressive procedures such as angiography or surgery.

  5. Development and validation of purged thermal protection systems for liquid hydrogen fuel tanks of hypersonic vehicles

    Science.gov (United States)

    Helenbrook, R. D.; Colt, J. Z.

    1977-01-01

    An economical, lightweight, safe, efficient, reliable, and reusable insulation system was developed for hypersonic cruise vehicle hydrogen fuel tanks. Results indicate that, a nitrogen purged, layered insulation system with nonpermeable closed-cell insulation next to the cryogenic tank and a high service temperature fibrous insulation surrounding it, is potentially an attractive solution to the insulation problem. For the postulated hypersonic flight the average unit weight of the purged insulation system (including insulation, condensate and fuel boil off) is 6.31 kg/sq m (1.29 psf). Limited cyclic tests of large specimens of closed cell polymethacrylimide foam indicate it will withstand the expected thermal cycle.

  6. Sex differences in the genetic architecture of lifespan in a seed beetle: extreme inbreeding extends male lifespan

    DEFF Research Database (Denmark)

    Bilde, T.; Maklakov, Alexei A.; Meisner, Katrine;

    2009-01-01

    -specific responses to inbreeding to study the genetic architecture of lifespan and mortality rates in Callosobruchus maculatus, a seed beetle that shows sexual dimorphism in lifespan. Two independent assays revealed opposing sex-specific responses to inbreeding. The combined data set showed that inbred males live...

  7. An effective rotational mating scheme for inbreeding reduction in captive populations illustrated by the rare sheep breed

    NARCIS (Netherlands)

    Windig, J.J.; Lansbergen, L.M.T.E.

    2008-01-01

    Within breeds and other captive populations, the risk of high inbreeding rates and loss of diversity can be high within (small) herds or subpopulations. When exchange of animals between different subpopulations is organised according to a rotational mating scheme, inbreeding rates can be restricted.

  8. Investigating inbreeding depression for heat stress tolerance in the model organism Drosophila melanogaster

    DEFF Research Database (Denmark)

    Pedersen, Kamilla Sofie; Pedersen, Louise Dybdahl; Sørensen, Anders Christian

    2012-01-01

    -year university students and discuss learning outcomes of the exercise as an example of inquiry-based science teaching. We use the model organism Drosophila melanogaster to test the ability of inbred and control (non-inbred) females to survive heat stress exposure. Flies were anaesthetised and collected...

  9. Inbreeding depression in Solanum carolinense (Solanaceae), a species with a plastic self-incompatibility response

    NARCIS (Netherlands)

    Mena-Ali, J.I.; Keser, L.H.; Stephenson, A.G.

    2008-01-01

    Solanum carolinense (horsenettle) is a highly successful weed with a gametophytic self-incompatibility (SI) system. Previous studies reveal that the strength of SI in S. carolinense is a plastic trait, associated with particular S-alleles. The importance of this variation in self-fertility on the

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

    NARCIS (Netherlands)

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

    2011-01-01

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

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

    NARCIS (Netherlands)

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

    2011-01-01

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

  12. Inbreeding and Outbreeding Depressions in the Penna Model as a Result of Crossover Frequency

    Science.gov (United States)

    Bońkowska, K.; Kula, M.; Cebrat, S.; Stauffer, D.

    The population in the sexual Penna aging model is first separated into several reproductively isolated groups. Then, after equilibration, sexual mixing between the groups is allowed. We study the changes in the population size due to this mixing and interpret them through a counterplay of purifying selection and of haplotype complementarity.

  13. Relationship between self-fertility, allocation of growth, and inbreeding depression in three coniferous species.

    Science.gov (United States)

    Frank C. Sorensen

    1999-01-01

    Mortality and growth of self and outcross families of three wind-pollinated, mixed-mating, long-lived conifers, Douglas-fir (Pseudotsuga menziesii), ponderosa pine (Pinus ponderosa), and noble fir (Abies procera) were followed from outplanting to age 26 (25 for noble fir) in spaced plantings at a common...

  14. High-throughput sequencing reveals inbreeding depression in a natural population

    NARCIS (Netherlands)

    Hoffman, Joseph I; Simpson, Fraser; David, Patrice; Rijks, Jolianne M|info:eu-repo/dai/nl/151266093; Kuiken, Thijs; Thorne, Michael A S; Lacy, Robert C; Dasmahapatra, Kanchon K

    2014-01-01

    Proxy measures of genome-wide heterozygosity based on approximately 10 microsatellites have been used to uncover heterozygosity fitness correlations (HFCs) for a wealth of important fitness traits in natural populations. However, effect sizes are typically very small and the underlying mechanisms

  15. Genomic Variation of Inbreeding and Ancestry in the Remaining Two Isle Royale Wolves.

    Science.gov (United States)

    Hedrick, Philip W; Kardos, Marty; Peterson, Rolf O; Vucetich, John A

    2017-03-01

    Inbreeding, relatedness, and ancestry have traditionally been estimated with pedigree information, however, molecular genomic data can provide more detailed examination of these properties. For example, pedigree information provides estimation of the expected value of these measures but molecular genomic data can estimate the realized values of these measures in individuals. Here, we generate the theoretical distribution of inbreeding, relatedness, and ancestry for the individuals in the pedigree of the Isle Royale wolves, the first examination of such variation in a wild population with a known pedigree. We use the 38 autosomes of the dog genome and their estimated map lengths in our genomic analysis. Although it is known that the remaining wolves are highly inbred, closely related, and descend from only 3 ancestors, our analyses suggest that there is significant variation in the realized inbreeding and relatedness around pedigree expectations. For example, the expected inbreeding in a hypothetical offspring from the 2 remaining wolves is 0.438 but the realized 95% genomic confidence interval is from 0.311 to 0.565. For individual chromosomes, a substantial proportion of the whole chromosomes are completely identical by descent. This examination provides a background to use when analyzing molecular genomic data for individual levels of inbreeding, relatedness, and ancestry. The level of variation in these measures is a function of the time to the common ancestor(s), the number of chromosomes, and the rate of recombination. In the Isle Royale wolf population, the few generations to a common ancestor results in the high variance in genomic inbreeding. © The American Genetic Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Whitey Swagelok SCHe Ball Valves Provide Isolation between SCHe Purge Lines C and D and the Process Vent

    Energy Technology Data Exchange (ETDEWEB)

    MISKA, C.R.

    2000-09-15

    These valves are 1/4 inch ball valves fabricated of 316 stainless steel. Packing is TFE (standard). They provide an isolation function betwen SCHe Purge Line C, (PV-V-*079), and Purge Line D, (PV-V-*080), and the Process Vent.

  17. Tri-leaflet valve design with a purge flow for heart-assist devices: an in vitro optimization study.

    Science.gov (United States)

    Timmel, Tobias; Seshadri, Santhosh; Goubergrits, Leonid; Affeld, Klaus; Kertzscher, Ulrich

    2012-01-01

    The objective of this study is to assess the effect of a purge flow on valves of pulsatile heart-assist devices. Clinical applications of these devices are still limited because of frequent thromboembolic complications. These complications often originate at the valves and the unavoidable flow separation regions that are found behind the leaflets. The flow separations cause a long residence time of blood that is considered particularly detrimental. To solve this problem, a valve with a purge flow is proposed. A purge flow is a jet, which is separated from the main blood flow and directed behind the leaflets into the sinus to flush it. Even though the purge flow does not prevent a flow separation, it shortens the residence time of the blood in the sinus. Thus, the purge flow improves the periodic washout of the blood in the region of flow separation. The complex purge flow was investigated in a tri-leaflet valve. The geometrical parameters of the valve were varied systematically. A statistical technique--the Taguchi method--was used to reduce the number of investigated models to 12. The flows through the resulting valve models were numerically simulated and analyzed. The evaluated models with the best results were subsequently investigated experimentally using different methods: hemodynamic tests in a valve tester and flow visualization using the dye washout method. It was shown that the purge flow can effectively wash out the sinus. Therefore, the purge flow valve reduces the potential of a thrombus formation normally associated with the valve.

  18. KPT系列吹扫装置的典型应用%Typical Applications of the KPT Series Purge Device

    Institute of Scientific and Technical Information of China (English)

    陈晶

    2012-01-01

    针对KPT系列吹扫装置原理进行了深入分析,并对吹扫装置的几种应用进行阐述。%More in-depth analysis of device principle for the KPT series purge is carried out and several purge applications are described in detail.

  19. Retrospective investigation of captive red wolf reproductive success in relation to age and inbreeding.

    Science.gov (United States)

    Lockyear, K M; Waddell, W T; Goodrowe, K L; MacDonald, S E

    2009-05-01

    The critically endangered red wolf (Canis rufus) has been subject to a strictly managed captive breeding program for three decades. A retrospective demographic analysis of the captive population was performed based on data from the red wolf studbook. Data analyses revealed a decrease in the effective population size relative to the total population size, and changes in age structure and inbreeding coefficients over time. To varying degrees, the probability of successful breeding and litter sizes declined in association with increasing dam age and sire inbreeding coefficients. Neonate survival also declined with increasing dam age. Recent changes in strategies regarding breed-pair recommendations have resulted in moderate increases in reproductive success.

  20. How Much Does Inbreeding Reduce Heterozygosity? Empirical Results from Aedes aegypti.

    Science.gov (United States)

    Powell, Jeffrey R; Evans, Benjamin R

    2017-01-11

    Deriving strains of mosquitoes with reduced genetic variation is useful, if not necessary, for many genetic studies. Inbreeding is the standard way of achieving this. Full-sib inbreeding the mosquito Aedes aegypti for seven generations reduced heterozygosity to 72% of the initial heterozygosity in contrast to the expected 13%. This deviation from expectations is likely due to high frequencies of deleterious recessive alleles that, given the number of markers studied (27,674 single nucleotide polymorphisms [SNPs]), must be quite densely spread in the genome.

  1. Influence of negative affect on decision making in women with restrictive and binge-purge type anorexia nervosa.

    Science.gov (United States)

    Danner, Unna N; Sternheim, Lot; Bijsterbosch, Jojanneke M; Dingemans, Alexandra E; Evers, Catharine; van Elburg, Annemarie A

    2016-05-30

    The present study aims to examine the influence of negative affect on decision making in women with anorexia nervosa (AN) compared to healthy control women and, secondly, to assess differences between the restrictive (ANR) and binge-purge (ANBP) subtypes. One hundred four women (32 with ANR, 32 with ANBP, and 40 healthy controls) participated. All women were asked to watch either a negative or a control film fragment, both followed by the Bechara Gambling Task (BGT). Before and after the fragments negative affect was measured. Additionally, relevant characteristics (e.g., overall depressive symptoms) were assessed. Differences in negative affect did not influence decision making performance. Independent of affective state, decision making was found to be impaired in women with ANBP (no learning effect on the BGT), but not in women with ANR. These findings highlight the importance of considering different AN subtypes when examining decision making processes. However, the role of negative affect on decision making remains uncertain. Since other affect related factors such as affect dysregulation may also play a role, future studies on decision making in AN should take the role of affect into account.

  2. Serotonergic dysfunction across the eating disorders: relationship to eating behaviour, purging behaviour, nutritional status and general psychopathology.

    Science.gov (United States)

    Monteleone, P; Brambilla, F; Bortolotti, F; Maj, M

    2000-09-01

    Several recent studies have pointed to a dysfunction of serotonin transmission in patients with eating disorders. Notwithstanding, it is not known whether serotonergic abnormalities are related primarily to eating and/or purging behaviour, nutritional status or general psychopathological dimensions. Therefore, by using a validated neuroendocrine strategy, we investigated central serotonergic function in patients with anorexia nervosa, bulimia nervosa or binge-eating disorder who differ on the above parameters. Plasma prolactin response to D-fenfluramine (30 mg p.o.) or placebo was measured in 58 drug-free female volunteers, comprising 15 underweight anorexic women, 18 bulimic women, 10 women with binge-eating disorder and 15 female healthy controls. Behavioural assessment included ratings of eating disorder symptoms, depression, aggression and food-related obsessions and compulsions. A significantly decreased prolactin response to D-fenfluramine was found in underweight anorexic women and in bulimics with high frequency bingeing ( > 2 binge episodes/day), but not in patients with binge-eating disorder or in bulimics with low frequency bingeing (nervosa. Moreover, they show, for the first time, that the hypothalamic serotonergic system is not altered in women with binge-eating disorder.

  3. A strategy analysis for genetic association studies with known inbreeding

    Directory of Open Access Journals (Sweden)

    del Giacco Stefano

    2011-07-01

    Full Text Available Abstract Background Association studies consist in identifying the genetic variants which are related to a specific disease through the use of statistical multiple hypothesis testing or segregation analysis in pedigrees. This type of studies has been very successful in the case of Mendelian monogenic disorders while it has been less successful in identifying genetic variants related to complex diseases where the insurgence depends on the interactions between different genes and the environment. The current technology allows to genotype more than a million of markers and this number has been rapidly increasing in the last years with the imputation based on templates sets and whole genome sequencing. This type of data introduces a great amount of noise in the statistical analysis and usually requires a great number of samples. Current methods seldom take into account gene-gene and gene-environment interactions which are fundamental especially in complex diseases. In this paper we propose to use a non-parametric additive model to detect the genetic variants related to diseases which accounts for interactions of unknown order. Although this is not new to the current literature, we show that in an isolated population, where the most related subjects share also most of their genetic code, the use of additive models may be improved if the available genealogical tree is taken into account. Specifically, we form a sample of cases and controls with the highest inbreeding by means of the Hungarian method, and estimate the set of genes/environmental variables, associated with the disease, by means of Random Forest. Results We have evidence, from statistical theory, simulations and two applications, that we build a suitable procedure to eliminate stratification between cases and controls and that it also has enough precision in identifying genetic variants responsible for a disease. This procedure has been successfully used for the beta-thalassemia, which is

  4. Depression - resources

    Science.gov (United States)

    Resources - depression ... Depression is a medical condition. If you think you may be depressed, see a health care provider. ... following organizations are good sources of information on depression : American Psychological Association -- www.apa.org/topics/depress/ ...

  5. Assessment of methylprednisolone purging efficacy on Daudi burkitt lymphoma cells from normal bone marrow.

    Science.gov (United States)

    Janakiraman, N; Niewenhuis, L M

    1991-01-01

    Studies on normal bone marrow and Daudi Burkitt lymphoma cells were performed to determine the efficacy of selective, in vitro chemopurging with methylprednisolone (MP). We found that MP reduces the number of lymphoma cells without significant damage to bone marrow cells. This information is important because we need to improve the existing in vitro purging regimens used to cleanse autologous marrows of metastatic disease before transplantation into cancer patients who have received high-dose chemotherapy. Normal human bone marrow (NBM) and Daudi lymphoma cells were treated in parallel with various purging regimens, NBM death was evaluated using soft-agar culture, while Daudi cell death was evaluated using one-week liquid culture. A protocol of 2.0 mg/mL of MP for four hours demonstrated optimal selectivity. When treatment was followed by cryopreservation, a 1.7 log purge of Daudi cells was increased to 2.3 logs while preserving 36% of committed NBM precursors. We repeated these experiments on a simulated contaminated marrow to model closely the mixture of normal and malignant cells found in advanced, metastatic disease. We evaluated this mixed system by flow cytometric immunoanalysis using the two-color CD10/CD20 markers to detect residual, viable Daudi cells. Our initial results were reproducible in this mixed-cell system, further supporting the evidence for effective in vitro purging of bone marrow using MP.

  6. Self-filling and self-purging apparatus for detecting spontaneous radiation from substances in fluids

    Science.gov (United States)

    Larson, I. Lauren; Chiles, Marion M.; Miller, V. Clint

    1993-01-01

    Disclosed herein is a radiation detector providing for the in situ automatic sampling of fluids containing substances emitting radiation, especially Cerenkov radiation. The detector permits sampling within well casings and is self-purging such that no additional provisions must be established for the storage and disposal of contaminated fluids.

  7. The ex vivo purge of cancer cells using oncolytic viruses: recent advances and clinical implications

    Directory of Open Access Journals (Sweden)

    Tsang JJ

    2015-01-01

    Full Text Available Jovian J Tsang,1,2 Harold L Atkins2,3 1Department of Biochemistry, University of Ottawa, 2Cancer Therapeutics, Ottawa Hospital Research Institute, 3Blood and Marrow Transplant Program, The Ottawa Hospital, Ottawa, ON, Canada Abstract: Hematological malignancies are treated with intensive high-dose chemotherapy, with or without radiation. This is followed by hematopoietic stem cell (HSC transplantation (HSCT to rescue or reconstitute hematopoiesis damaged by the anticancer therapy. Autologous HSC grafts may contain cancer cells and purging could further improve treatment outcomes. Similarly, allogeneic HSCT may be improved by selectively purging alloreactive effector cells from the graft rather than wholesale immune cell depletion. Viral agents that selectively replicate in specific cell populations are being studied in experimental models of cancer and immunological diseases and have potential applications in the context of HSC graft engineering. This review describes preclinical studies involving oncolytic virus strains of adenovirus, herpes simplex virus type 1, myxoma virus, and reovirus as ex vivo purging agents for HSC grafts, as well as in vitro and in vivo experimental studies using oncolytic coxsackievirus, measles virus, parvovirus, vaccinia virus, and vesicular stomatitis virus to eradicate hematopoietic malignancies. Alternative ex vivo oncolytic virus strategies are also outlined that aim to reduce the risk of relapse following autologous HSCT and mitigate morbidity and mortality due to graft-versus-host disease in allogeneic HSCT. Keywords: hematopoietic stem cells, oncolytic virus, hematopoietic stem cell transplantation, stem cell graft purging, hematopoietic malignancy, graft vs host disease

  8. EVALUATION OF VAPOR EQUILIBRATION AND IMPACT OF PURGE VOLUME ON SOIL-GAS SAMPLING RESULTS

    Science.gov (United States)

    Sequential sampling was utilized at the Raymark Superfund site to evaluate attainment of vapor equilibration and the impact of purge volume on soil-gas sample results. A simple mass-balance equation indicates that removal of three to five internal volumes of a sample system shou...

  9. Rituximab purging and/or maintenance in patients undergoing autologous transplantation for relapsed follicular lymphoma

    DEFF Research Database (Denmark)

    Pettengell, Ruth; Schmitz, Norbert; Gisselbrecht, Christian

    2013-01-01

    The objective of this randomized trial was to assess the efficacy and safety of rituximab as in vivo purging before transplantation and as maintenance treatment immediately after high-dose chemotherapy and autologous stem-cell transplantation (HDC-ASCT) in patients with relapsed follicular lympho...

  10. Steam and fuel oil supply and purge valve with cooling steam feature

    Energy Technology Data Exchange (ETDEWEB)

    Buchanan, B.F.; Buchanan, J.R.

    1991-09-17

    This patent describes a steam and fuel oil supply and purge valve. It comprises a valve body defining steam and oil inlet ports, at least one discharge port, a steam purge passageway interconnecting the steam inlet and discharge ports, an oil supply passageway interconnecting the oil inlet and discharge ports, a cooling steam passageway interconnecting the steam inlet and discharge ports, a steam valve and actuator member movable between first, second, third, and fourth positions in the valve body and operable to open and close the steam purge and cooling steam passageways, a small metering passageway in the steam valve and actuator member which is so dimensioned and located as to open prior to full opening movement of the valve member and actuator relative to its seat, an oil valve member movable between first and second positions to open and close the oil supply passageway, biasing means urging the oil valve member toward its second and closed positions, the steam valve and actuator member in its first and second positions respectively closing and opening the steam purge passageway.

  11. Efeito da endogamia na produção de sementes de pepino caipira Effect of inbreeding in seeds yield of "caipira" cucumber

    Directory of Open Access Journals (Sweden)

    Amanda Regina Godoy

    2006-01-01

    Full Text Available Este trabalho teve por objetivo verificar se existe depressão por endogamia para produção de sementes com sucessivas gerações de autofecundações em uma população de pepino caipira, obtida a partir da geração F2 do cruzamento (Safira x Hatem x Safira. O delineamento experimental utilizado foi em blocos ao acaso, com seis tratamentos (diferentes gerações de autofecundação - S0 a S5, quatro repetições e cinco plantas por parcela. Não houve diferença estatística para todas as características avaliadas (número de frutos por planta, massa de sementes por planta, massa de sementes por fruto, número de sementes por planta, número de sementes por fruto, massa de 100 sementes, teste-padrão de germinação, primeira contagem do teste-padrão de germinação e índice de velocidade de germinação, observando-se que a endogamia não afetou a produção e qualidade das sementes nessa população.The objective of this work was to evaluate the inbreeding depression after successive generations of self-pollination in a cucumber population, generation F2 from the cross (Safira x Hatem x Safira. Experimental design was randomized blocks with six treatments (different generations of self-pollination - S0 to S5, four replicates and five plants per plot. There was no statistical difference among all evauated characteristics (fruit number per plant, number and weight of seeds per plant and per fruit, germination test, first count of germinated seeds, index of germination a and weight of 100 seeds, showing that inbreeding did not affect seed production and quality in this population.

  12. Eating Patterns in Youth with Restricting and Binge Eating/Purging Type Anorexia Nervosa

    Science.gov (United States)

    Elran-Barak, Roni; Accurso, Erin C.; Goldschmidt, Andrea B.; Sztainer, Maya; Byrne, Catherine; Le Grange, Daniel

    2015-01-01

    Objective To describe eating patterns in youth with restricting and binge/purge type anorexia nervosa (AN) and to examine whether eating patterns are associated with binge eating or purging behaviors. Method Participants included 160 children and adolescents (M=15.14±2.17 years) evaluated at The University of Chicago Eating Disorders Program who met criteria for DSM-5 restrictive type AN (AN-R; 75%; n=120) or binge eating/purging type AN (AN-BE/P; 25%; n=40). All participants completed the Eating Disorder Examination (EDE) upon initial evaluation. Results Youth with AN-R and AN-BE/P differed in their eating patterns, such that youth with AN-R consumed meals and snacks more regularly relative to youth with AN-BE/P. Among youth with AN-BE/P, skipping dinner was associated with a greater number of binge eating episodes (r=−.379, p<0.05), while skipping breakfast was associated with a greater number of purging episodes (r=−.309, p<0.05). Discussion Youth with AN-R generally follow a regular meal schedule, but are likely consuming insufficient amounts of food across meals and snacks. In contrast, youth with AN-BE/P tend to have more irregular eating patterns, which may play a role in binge eating and purging behaviors. Adults monitoring of meals may be beneficial for youth with AN, and particularly those with AN-BE/P who engage in irregular eating patterns. PMID:24777645

  13. The effects of inbreeding and heat stress on male sterility in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Pedersen, Louise Dybdahl; Pedersen, Asger Roer; Bijlsma, Kuke

    2011-01-01

    in benign and stressful environments using Drosophila melanogaster as a model organism. Male sterility was compared in 21 inbred lines and five non-inbred control lines at 25.0 and 29.0 °C. The effect of inbreeding on sterility was significant only at 29.0 °C. This stress-induced increase in sterility...

  14. Effects of seed size, inbreeding and maternal sex on offspring fitness in gynodioecious Plantago coronopus

    NARCIS (Netherlands)

    Koelewijn, H.P.; Damme, van J.M.M.

    2005-01-01

    1 Male steriles (MS) must have a fitness advantage relative to hermaphrodites (H) if they are to be maintained in gynodioecious species. We report experiments in which we disentangle the relative contributions of seed size, inbreeding and maternal sex to the fitness advantage of male steriles in Pla

  15. Inbreeding effects on resistance and transmission-related traits in the Silene-Microbotryum pathosystem

    NARCIS (Netherlands)

    Ouborg, N.J.; Biere, A.; Mudde, C.L.

    2000-01-01

    Inbreeding in local host populations will be a common phenomenon in host-pathogen systems that are characterized by metapopulation dynamics, i.e., frequent extinction and recolonization of local host populations by small numbers of founding individuals. As an example of a pathosystem with metapopula

  16. Towards a complete North American Anabaptist Genealogy II: analysis of inbreeding.

    Science.gov (United States)

    Agarwala, R; Schäffer, A A; Tomlin, J F

    2001-08-01

    We describe a large genealogy data base, which can be searched by computer, of 295,095 Amish and Mennonite individuals. The data base was constructed by merging our existing Anabaptist Genealogy Database 2.0 containing approximately 85,000 individuals with a genealogy file containing approximately 242,000 individuals, kindly provided by Mr. James Hostetler. The merging process corrected thousands of inconsistencies and eliminated hundreds of duplicate individuals. Geneticists have long been interested in Anabaptist populations because they are closed and have detailed written genealogies. The creation of an enlarged and unified data base affords the opportunity to examine inbreeding trends and correlates in these populations. We show the following results. The frequency of consanguineous marriages shows steady increase over time and reached approximately 85% for individuals born in 1940-1959. Among consanguineous marriages, the median kinship coefficient stayed stable in the 19th century, but rose from 0.0115 to 0.0151 in the 20th century. There are statistically significant associations (p < 0.0001) between inbreeding and family size and interbirth intervals in the 20th century. There is an association (p < 0.0005) between inbreeding and early death for individuals born in 1920-1959. However, this association reverses dramatically (p < 0.0005 in the opposite direction) for individuals born in 1960-1979. We tested for an association between inbreeding and being the mother of twins, but found none.

  17. Accelerating the inbreeding of multi-parental recombinant inbred lines generated by sibling matings.

    Science.gov (United States)

    Welsh, Catherine E; McMillan, Leonard

    2012-02-01

    Inbred model organisms are powerful tools for genetic studies because they provide reproducible genomes for use in mapping and genetic manipulation. Generating inbred lines via sibling matings, however, is a costly undertaking that requires many successive generations of breeding, during which time many lines fail. We evaluated several approaches for accelerating inbreeding, including the systematic use of back-crosses and marker-assisted breeder selection, which we contrasted with randomized sib-matings. Using simulations, we explored several alternative breeder-selection methods and monitored the gain and loss of genetic diversity, measured by the number of recombination-induced founder intervals, as a function of generation. For each approach we simulated 100,000 independent lines to estimate distributions of generations to achieve full-fixation as well as to achieve a mean heterozygosity level equal to 20 generations of randomized sib-mating. Our analyses suggest that the number of generations to fully inbred status can be substantially reduced with minimal impact on genetic diversity through combinations of parental backcrossing and marker-assisted inbreeding. Although simulations do not consider all confounding factors underlying the inbreeding process, such as a loss of fecundity, our models suggest many viable alternatives for accelerating the inbreeding process.

  18. Inbreeding and loss of genetic variation in a reintroduced population of Mauritius Kestrel.

    Science.gov (United States)

    Ewing, Steven R; Nager, Ruedi G; Nicoll, Malcolm A C; Aumjaud, Aurelien; Jones, Carl G; Keller, Lukas F

    2008-04-01

    Many populations have recovered from severe bottlenecks either naturally or through intensive conservation management. In the past, however, few conservation programs have monitored the genetic health of recovering populations. We conducted a conservation genetic assessment of a small, reintroduced population of Mauritius Kestrel (Falco punctatus) to determine whether genetic deterioration has occurred since its reintroduction. We used pedigree analysis that partially accounted for individuals of unknown origin to document that (1) inbreeding occurred frequently (2.6% increase per generation; N(eI)= 18.9), (2) 25% of breeding pairs were composed of either closely or moderately related individuals, (3) genetic diversity has been lost from the population (1.6% loss per generation; N(eV)= 32.1) less rapidly than the corresponding increase in inbreeding, and (4) ignoring the contribution of unknown individuals to a pedigree will bias the metrics derived from that pedigree, ultimately obscuring the prevailing genetic dynamics. The rates of inbreeding and loss of genetic variation in the subpopulation of Mauritius Kestrel we examined were extreme and among the highest yet documented in a wild vertebrate population. Thus, genetic deterioration may affect this population's long-term viability. Remedial conservation strategies are needed to reduce the impact of inbreeding and loss of genetic variation in this species. We suggest that schemes to monitor genetic variation after reintroduction should be an integral component of endangered species recovery programs.

  19. Single-locus complementary sex determination in the inbreeding wasp Euodynerus foraminatus Saussure (Hymenoptera: Vespidae).

    Science.gov (United States)

    Stahlhut, J K; Cowan, D P

    2004-03-01

    The Hymenoptera have arrhenotokous haplodiploidy in which males normally develop from unfertilized eggs and are haploid, while females develop from fertilized eggs and are diploid. Multiple sex determination systems are known to underlie haplodiploidy, and the best understood is single-locus complementary sex determination (sl-CSD) in which sex is determined at a single polymorphic locus. Individuals heterozygous at the sex locus develop as females; individuals that are hemizygous (haploid) or homozygous (diploid) at the sex locus develop as males. sl-CSD can be detected with inbreeding experiments that produce diploid males in predictable proportions as well as sex ratio shifts due to diploid male production. This sex determination system is considered incompatible with inbreeding because the ensuing increase in homozygosity increases the production of diploid males that are inviable or infertile, imposing a high cost on matings between close relatives. However, in the solitary hunting wasp Euodynerus foraminatus, a species suspected of having sl-CSD, inbreeding may be common due to a high incidence of sibling matings at natal nests. In laboratory crosses with E. foraminatus, we find that sex ratios and diploid male production (detected as microsatellite heterozygosity) are consistent with sl-CSD, but not with other sex determination systems. This is the first documented example of sl-CSD in a hymenopteran with an apparent natural history of inbreeding, and thus presents a paradox for our understanding of hymenopteran genetics.

  20. Inbreeding affects fecundity of American mink (Neovison vison) in Danish farm mink

    DEFF Research Database (Denmark)

    Demontis, Ditte; Larsen, P F; Bækgaard, H

    2011-01-01

    Inbreeding is an increasing problem in farmed mink, because of limited exchange of individuals between farms. In this study, genetic relatedness within seven American mink (Neovison vison) colour strains originating from 13 different mink farms in Denmark was analysed using 21 polymorphic microsa...

  1. Postpartum depression

    Science.gov (United States)

    Depression - postpartum; Postnatal depression; Postpartum psychological reactions ... behavioral therapy (CBT) and interpersonal therapy (IPT) are types of talk therapy that often help postpartum depression. ...

  2. Molds in Brined Cucumbers: Cause of Softening During Air-Purging of Fermentations †

    Science.gov (United States)

    Costilow, Ralph N.; Gates, Karen; Lacy, Melvyn L.

    1980-01-01

    Softening of cucumbers in fermentations purged at high air-flow rates was caused by molds growing in the brined cucumbers, not in the brine. This conclusion is based on the following results: (i) no microorganisms were isolated in significant numbers from brines that caused softening of pasteurized brined cucumbers, (ii) no pectinolytic enzyme activities were produced in cucumber brines in the absence of cucumbers, (iii) the pickles in some air-purged fermentations became very soft without the appearance of any pectinolytic enzyme activity in the brine, (iv) mold hyphae were consistently observed in tissues of soft pickles, (v) molds consistently developed in cultures of slices of surface sterilized cucumbers taken from fermentations in which soft pickles were subsequently found, and (vi) molds belonging to the genera Alternaria, Fusarium, and Mucor isolated from slices all softened pasteurized brined cucumbers. Images PMID:16345619

  3. EVALUATION OF THREE-DIMENSIONAL NUMERICAL MODEL FOR SALINE INTRUSION AND PURGING IN SEWAGE OUTFALLS

    Institute of Scientific and Technical Information of China (English)

    WU Wei; YAN Zhong-min

    2007-01-01

    Saline intrusion into sewage outfalls will greatly decrease the efficiency of the structures. The numerical model for this flow has been limited to one- and two-dimensional ones. In this article, a three-dimensional numerical model for saline intrusion and purging in sewage outfalls was developed. The flow was modeled in three dimensions under turbulent conditions with the RNG turbulence model. The numerical results provided quantitative evidence of the fundamental flow mechanisms that took place during saline intrusion and purging. The comparisons of the results with that of two-dimensional model and that of experiments indicate that the three-dimensional numerical model developed in this article is more effective in predicting the internal flow in outfalls.

  4. A Clinical Study on Haunglian Fire-Purging Mixture In Treatment of 46 Cases of Primary Hypertension

    Institute of Scientific and Technical Information of China (English)

    李运伦

    2005-01-01

    In order to observe the therapeutic effects of Huanglian Fire-Purging Mixture (黄连清降合剂) on primary hypertension, 46 cases of primary hypertension in the treatment group were treated with Huanglian Fire-Purging Mixture to clear away heat from the liver, relieve mental stress, purge fire and remove toxin;and the other 26 cases of primary hypertension in the control group were treated with Niuhuang Bolus for Lowering Blood Pressure (牛黄降压丸). The effect in the treatment group was obviously superior to that in the control group (P<0.05). The Huanglian Fire-Purging Mixture shows noticeable effects 3-6 hours after medication. The mixture can improve the clinical symptoms, the left ventricular diastolic function and myocardial ischemia, correct dyslipoproteinemia and dysglycemia, and reduce blood viscosity. And it is safe and with no obvious adverse reactions.

  5. Interplay between habitat fragmentation and climate change : inbreeding affects the response to thermal stress in Drosophila melanogaster

    NARCIS (Netherlands)

    Joubert, D.; Bijlsma, R.

    2010-01-01

    Climate change, exerting thermal stress, and habitat destruction and fragmentation, resulting in genetic drift and inbreeding, are amongst the most disturbing human activities that endanger global biodiversity. We studied the interplay between these 2 processes using Drosophila melanogaster as a

  6. On the Adaptive Origins and Maladaptive Consequences of Human Inbreeding : Parasite Prevalence, Immune Functioning, and Consanguineous Marriage

    NARCIS (Netherlands)

    Hoben, Ashley D.; Buunk, Abraham P.; Fincher, Corey L.; Thornhill, Randy; Schaller, Mark

    2010-01-01

    We propose that consanguineous marriages arise adaptively in response to high parasite prevalence and function to maintain coadapted gene complexes and associated local adaptation that defend against local pathogens. Therefore, a greater prevalence of inbreeding by consanguineous marriage is

  7. Change in field turbidity and trace element concentrations during well purging

    Science.gov (United States)

    Gibs, J.; Szabo, Z.; Ivahnenko, T.; Wilde, F.D.

    2000-01-01

    Various physical and chemical properties were monitored sequentially in the field during well purging as indicators of stabilization of the composition of the water in the well. Turbidity was monitored on site during purging of oxic water from three wells with screened intervals open to an unconfined aquifer system in the Coastal Plain of southern New Jersey to determine if stabilization of turbidity is a reliable indicator of the optimum purge time required to collect unbiased trace element samples. Concurrent split (one filtered, one unfiltered) samples collected during purging of the wells were analyzed for concentrations of trace elements so that the relationships between trace element concentrations and turbidity could be compared. Turbidity correlated with the whole water recoverable (WWR) concentration of trace element species, such as iron (Fe), aluminum (Al), and manganese (Mn) in the oxic ground water. Turbidity appeared to be independent of other field-measured characteristics of water such as conductivity, pH, temperature, and dissolved oxygen. The WWR concentrations of lead and copper, considered to be hydrophobic, correlated significantly with the sum of the WWR concentration of Fe, Al, and Mn. High values of field-measured turbidity were a key indicator of an overestimate of ambient hydrophobic trace element WWR concentrations. Stabilization of turbidity was a better indicator of stable, unfiltered trace element concentrations than were the other commonly measured field characteristics. At one well, turbidity was a better indicator of stable, filtered trace element concentrations than the other commonly measured field characteristics. As analytical methods for trace elements improve resulting in smaller MRLs (method reporting levels) and better precision, turbidity of ground water at values of less than 10 NTU (nepheiometric turbidity units) will become important in interpreting the significance of both unfiltered and filtered sample results.

  8. The purge of spanish education during franquism (1936-1975. The institutionalization of a repression

    Directory of Open Access Journals (Sweden)

    Carlos de Pablo Lobo

    2007-09-01

    Full Text Available Work on the trial against Spanish teaching profession because of politic reasons, from the beginning of the Spanish Civil War (1936-1939 to the end of the General Francisco Franco dictatorship (1939-1975. It includes a legislation research and it also studies the reasons, institutions and the different periods in which the course is going through. Key words: Repression, Purge, Spanish teaching, Civil War, Elementary education, Franquism, Education methods. 

  9. A purge and trap integrated microGC platform for chemical identification in aqueous samples.

    Science.gov (United States)

    Akbar, Muhammad; Narayanan, Shree; Restaino, Michael; Agah, Masoud

    2014-07-07

    The majority of current micro-scale gas chromatography (μGC) systems focus on air sampling to detect volatile organic compounds (VOCs). However, purging the VOCs from a water sample using microsystems is an unchartered territory. Various organic compounds used in everyday life find their way to water bodies. Some of these water organic compounds (WOCs) persist or degrade slowly, threatening not just human existence but also aquatic life. This article reports the first micro-purge extractor (μPE) chip and its integration with a micro-scale gas chromatography (μGC) system for the extraction and analysis of water organic compounds (WOCs) from aqueous samples. The 2 cm × 3 cm μPE chip contains two inlet and outlet ports and an etched cavity sealed with a Pyrex cover. The aqueous sample is introduced from the top inlet port while a pure inert gas is supplied from the side inlet to purge WOCs from the μPE chip. The outlets are assigned for draining water from the chip and for directing purged WOCs to the micro-thermal preconcentrator (μTPC). The trapped compounds are desorbed from the μTPC by resistive heating using the on-chip heater and temperature sensor, are separated by a 2 m long, 80 μm wide, and 250 μm deep polydimethylsiloxane (OV-1) coated μGC separation column, and are identified using a micro-thermal conductivity detector (μTCD) monolithically integrated with the column. Our experiments indicate that the combined system is capable of providing rapid chromatographic separation (<1.5 min) for quaternary WOCs namely toluene, tetrachloroethylene (PCE), chlorobenzene and ethylbenzene with a minimum detection concentration of 500 parts-per-billion (ppb) in aqueous samples. The proposed method is a promising development towards the future realization of a miniaturized system for sensitive, on-site and real-time field analysis of organic contaminants in water.

  10. Hepatocytes isolated from neoplastic liver-immunomagnetic purging as a new source for transplantation

    Institute of Scientific and Technical Information of China (English)

    Aravin Gunasegaram; Javed Akhter; Peng Yao; Loreena A Johnson; Stephen M Riodan; David L Morris

    2008-01-01

    AIM: To investigate whether hepatocytes isolated from macroscopically normal liver during hepatic resection for neoplasia could provide a novel source of healthy hepatocytes, including the development of reliable protocols for malignant cells removal from the hepatocyte preparation.METHODS: Hepatocytes were procured from resected liver of 18 patients with liver tumors using optimised digestion and cell-enrichment protocols. Suspensions of various known quantities of the HT-29 tumor cell line and patient hepatocytes were treated or not with Ep-CAM-antibody-coated immunomagnetic beads in order to investigate the efficacy of tumor-purging by immunomagnetic depletion, using a semi-quantitative RT-PCR method developed to detect tumor cells.Immunomagnetic bead-treated or bead-untreated tumor cell-hepatocyte suspensions were transplanted intra-peritoneally in Balb/C nude mice to assess the rates of tumor development.RESULTS: Mean viable hepatocyte yield was 9.3 x 106 cells per gram of digested liver with mean viability of 70.5%. Immunomagnetic depletion removed tumor cells to below the RT-PCR detection-threshold of 1 tumor cell in 106 hepatocytes, representing a maximum tumor purging efficacy of greater than 400000-fold.Transplanted, immunomagnetic bead-purged tumor cell-hepatocyte suspensions did not form peritoneal tumors in Balb/C nude mice. Co-transplantation of hepatocytes with tumor cells did not increase tumorigenesis of the tumor cells.CONCLUSION: Immunomagnetic depletion appears to be an effective method of purging contaminating tumor cells to below threshold for likely tumorigenesis.Along with improved techniques for isolation of large numbers of viable hepatocytes, normal liver resected for neoplasia has potential as another clinically useful source of hepatocytes for transplantation.

  11. Numerical investigation of the interaction between upstream cavity purge flow and main flow in low aspect ratio turbine cascade

    Institute of Scientific and Technical Information of China (English)

    Jia Wei; Liu Huoxing

    2013-01-01

    In modem gas turbines,rim seal located between the stator-disc and rotor-disc is used to prevent hot-gas ingestion into the inner stage-gap of high pressure turbine.However,the purge flow supplied to the cavity through the rim seal interacts with the main flow,producing additional aerodynamic loss due to the mixing process which plays a significant role in the formation,development and evolution of downstream secondary flow.In this paper,a set of cascade representative of low aspect ratio turbine is selected to numerically investigate the influence of upstream cavity purge flow on the hub secondary flow structure and aerodynamic loss.Cascade with/without upstream cavity and four different purge mass flow rates are all taken into account in this simulation.Then,a deep insight into the loss mechanism of interaction between purge flow and main flow is gained.The results show that the presence of cavity and purge flow has a significant impact on the main flow which not only changes the vortex structure in both the passage and upstream cavity,but also alters the cascade exit flow angle distribution along the spanwise.Moreover,aerodynamic loss in the cascade rises with the increase of purge flow rate while the sealing effect is also enhanced.Therefore,the effect of upstream cavity purge flow must be considered in the process of turbine aerodynamic design.What is more,it is necessary to minimize the purge flow rate in order to reduce aerodynamic loss on the premise of satisfying cooling requirements.

  12. Acute gastric dilatation in a patient with anorexia nervosa binge/purge subtype.

    Science.gov (United States)

    Tweed-Kent, Ailis M; Fagenholz, Peter J; Alam, Hasan B

    2010-10-01

    Acute gastric dilatation is a rare complication of anorexia nervosa binge/purge subtype that results from gastrointestinal abnormalities, including decreased gastric motility and delayed gastric emptying. Early diagnosis and intervention is critical since delay may result in gastric necrosis, perforation, shock, and death. We report a 26-year-old female with anorexia nervosa binge/purge subtype, who presented with abdominal pain and nausea after a binge episode. Abdominal radiography and computed tomography showed a grossly dilated stomach measuring 32 cm × 17.9 cm consistent with acute gastric dilatation. She underwent exploratory laparotomy with gastrotomy and gastric decompression, and recovered uneventfully. Initially, the patient denied the binge episode, as many patients with eating disorders do, but later revealed an extensive history of anorexia nervosa binge/purge subtype. This case stresses the importance of obtaining a thorough history of eating disorders and maintaining a high index of suspicion for acute gastric dilatation in young women who present with abdominal pain and distention.

  13. The ex vivo purge of cancer cells using oncolytic viruses: recent advances and clinical implications.

    Science.gov (United States)

    Tsang, Jovian J; Atkins, Harold L

    2015-01-01

    Hematological malignancies are treated with intensive high-dose chemotherapy, with or without radiation. This is followed by hematopoietic stem cell (HSC) transplantation (HSCT) to rescue or reconstitute hematopoiesis damaged by the anticancer therapy. Autologous HSC grafts may contain cancer cells and purging could further improve treatment outcomes. Similarly, allogeneic HSCT may be improved by selectively purging alloreactive effector cells from the graft rather than wholesale immune cell depletion. Viral agents that selectively replicate in specific cell populations are being studied in experimental models of cancer and immunological diseases and have potential applications in the context of HSC graft engineering. This review describes preclinical studies involving oncolytic virus strains of adenovirus, herpes simplex virus type 1, myxoma virus, and reovirus as ex vivo purging agents for HSC grafts, as well as in vitro and in vivo experimental studies using oncolytic coxsackievirus, measles virus, parvovirus, vaccinia virus, and vesicular stomatitis virus to eradicate hematopoietic malignancies. Alternative ex vivo oncolytic virus strategies are also outlined that aim to reduce the risk of relapse following autologous HSCT and mitigate morbidity and mortality due to graft-versus-host disease in allogeneic HSCT.

  14. The influence of purge times on the yields of essential oil components extracted from plants by pressurized liquid extraction.

    Science.gov (United States)

    Wianowska, Dorota

    2014-01-01

    The influence of different purge times on the yield of the main essential oil constituents of rosemary (Rosmarinus officinalis L.), thyme (Thymus vulgaris L.), and chamomile (Chamomilla recutita L.) was investigated. The pressurized liquid extraction process was performed by applying different extraction temperatures and solvents. The results presented in the paper show that the estimated yield of essential oil components extracted from the plants in the pressurized liquid extraction process is purge time-dependent. The differences in the estimated yields are mainly connected with the evaporation of individual essential oil components and the applied solvent during the purge; the more volatile an essential oil constituent is, the greater is its loss during purge time, and the faster the evaporation of the solvent during the purge process is, the higher the concentration of less volatile essential oil components in the pressurized liquid extraction receptacle. The effect of purge time on the estimated yield of individual essential oil constituents is additionally differentiated by the extraction temperature and the extraction ability of the applied solvent.

  15. Effect of inbreeding on juvenile mortality in some small mammal species.

    Science.gov (United States)

    Ralls, K; Ballou, J

    1982-04-01

    In breeding records for 12 species of small mammals from 9 families in 3 orders, individuals with an inbreeding coefficient of 0 were classified as non-inbred, those with inbreeding coefficients greater than 0 as inbred. Juvenile mortality was defined as all deaths prior to 1/2 of the age of sexual maturity for each species. It was significantly higher for inbred than for noninbred animals in 11 of the 12 species using a 1-tailed sign test, and by Fisher's exact test in 3 species. Monodelphis domestica, Wiedomys pyrrhorhinos and and Dolichotis salinicola. The higher mortality of inbred young of the species with the largest sample size, Elephantulus rufescens, was irrespective of litter size and of the parity of the dam.

  16. Autosomal recessive disorders in Saguenay-Lac-Saint-Jean (Quebec, Canada): a study of inbreeding.

    Science.gov (United States)

    De Braekeleer, M; Gauthier, S

    1996-01-01

    Saguenay Lac-Saint-Jean (SLSJ) is a geographically isolated region of northeastern Quebec in which several autosomal recessive disorders have a high incidence. We calculated the inbreeding coefficients of 567 probands and compared them to 1701 matched control individuals. The mean inbreeding coefficient of the group containing all 567 probands was 2.73 times higher than that of the controls (0.001772 versus 0.00065). Thirteen percent (75/567) of the probands were inbred, but only 5% were born to matings between spouses related as second-degree cousins or closer. No marriage between uncle and niece and only two marriages between first-degree cousins were identified in the disorder group. These results strongly suggest that the high incidence of the autosomal recessive disorders in SLSJ is the result of a founder effect.

  17. Decoding an olfactory mechanism of kin recognition and inbreeding avoidance in a primate

    Science.gov (United States)

    2009-01-01

    Background Like other vertebrates, primates recognize their relatives, primarily to minimize inbreeding, but also to facilitate nepotism. Although associative, social learning is typically credited for discrimination of familiar kin, discrimination of unfamiliar kin remains unexplained. As sex-biased dispersal in long-lived species cannot consistently prevent encounters between unfamiliar kin, inbreeding remains a threat and mechanisms to avoid it beg explanation. Using a molecular approach that combined analyses of biochemical and microsatellite markers in 17 female and 19 male ring-tailed lemurs (Lemur catta), we describe odor-gene covariance to establish the feasibility of olfactory-mediated kin recognition. Results Despite derivation from different genital glands, labial and scrotal secretions shared about 170 of their respective 338 and 203 semiochemicals. In addition, these semiochemicals encoded information about genetic relatedness within and between the sexes. Although the sexes showed opposite seasonal patterns in signal complexity, the odor profiles of related individuals (whether same-sex or mixed-sex dyads) converged most strongly in the competitive breeding season. Thus, a strong, mutual olfactory signal of genetic relatedness appeared specifically when such information would be crucial for preventing inbreeding. That weaker signals of genetic relatedness might exist year round could provide a mechanism to explain nepotism between unfamiliar kin. Conclusion We suggest that signal convergence between the sexes may reflect strong selective pressures on kin recognition, whereas signal convergence within the sexes may arise as its by-product or function independently to prevent competition between unfamiliar relatives. The link between an individual's genome and its olfactory signals could be mediated by biosynthetic pathways producing polymorphic semiochemicals or by carrier proteins modifying the individual bouquet of olfactory cues. In conclusion, we

  18. Decoding an olfactory mechanism of kin recognition and inbreeding avoidance in a primate

    Directory of Open Access Journals (Sweden)

    Charpentier Marie JE

    2009-12-01

    Full Text Available Abstract Background Like other vertebrates, primates recognize their relatives, primarily to minimize inbreeding, but also to facilitate nepotism. Although associative, social learning is typically credited for discrimination of familiar kin, discrimination of unfamiliar kin remains unexplained. As sex-biased dispersal in long-lived species cannot consistently prevent encounters between unfamiliar kin, inbreeding remains a threat and mechanisms to avoid it beg explanation. Using a molecular approach that combined analyses of biochemical and microsatellite markers in 17 female and 19 male ring-tailed lemurs (Lemur catta, we describe odor-gene covariance to establish the feasibility of olfactory-mediated kin recognition. Results Despite derivation from different genital glands, labial and scrotal secretions shared about 170 of their respective 338 and 203 semiochemicals. In addition, these semiochemicals encoded information about genetic relatedness within and between the sexes. Although the sexes showed opposite seasonal patterns in signal complexity, the odor profiles of related individuals (whether same-sex or mixed-sex dyads converged most strongly in the competitive breeding season. Thus, a strong, mutual olfactory signal of genetic relatedness appeared specifically when such information would be crucial for preventing inbreeding. That weaker signals of genetic relatedness might exist year round could provide a mechanism to explain nepotism between unfamiliar kin. Conclusion We suggest that signal convergence between the sexes may reflect strong selective pressures on kin recognition, whereas signal convergence within the sexes may arise as its by-product or function independently to prevent competition between unfamiliar relatives. The link between an individual's genome and its olfactory signals could be mediated by biosynthetic pathways producing polymorphic semiochemicals or by carrier proteins modifying the individual bouquet of

  19. GESP: A computer program for modeling genetic effective population size, inbreeding, and divergence in substructured populations.

    Science.gov (United States)

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

    2017-03-24

    The genetically effective population size (Ne) is of key importance for quantifying rates of inbreeding and genetic drift, and is often used in conservation management to set targets for genetic viability. The concept was developed for single, isolated populations and the mathematical means for analyzing the expected Ne in complex, subdivided populations have previously not been available. We recently developed such analytical theory and central parts of that work have now been incorporated into a freely available software tool presented here. GESP (Genetic Effective population size, inbreeding, and divergence in Substructured Populations) is R-based and designed to model short and long term patterns of genetic differentiation and effective population size of subdivided populations. The algorithms performed by GESP allow exact computation of global and local inbreeding and eigenvalue effective population size, predictions of genetic divergence among populations (GST) as well as departures from random mating (FIS, FIT) while varying i) subpopulation census and effective size, separately or including trend of the global population size, ii) rate and direction of migration between all pairs of subpopulations, iii) degree of relatedness and divergence among subpopulations, iv) ploidy (haploid or diploid), and v) degree of selfing. Here, we describe GESP and exemplify its use in conservation genetics modeling. This article is protected by copyright. All rights reserved.

  20. Mutual mate choice: when it pays both sexes to avoid inbreeding.

    Science.gov (United States)

    Lihoreau, Mathieu; Zimmer, Cédric; Rivault, Colette

    2008-01-01

    Theoretical models of sexual selection predict that both males and females of many species should benefit by selecting their mating partners. However, empirical evidence testing and validating this prediction is scarce. In particular, whereas inbreeding avoidance is expected to induce sexual conflicts, in some cases both partners could benefit by acting in concert and exerting mutual mate choice for non-assortative pairings. We tested this prediction with the gregarious cockroach Blattella germanica (L.). We demonstrated that males and females base their mate choice on different criteria and that choice occurs at different steps during the mating sequence. Males assess their relatedness to females through antennal contacts before deciding to court preferentially non-siblings. Conversely, females biased their choice towards the most vigorously courting males that happened to be non-siblings. This study is the first to demonstrate mutual mate choice leading to close inbreeding avoidance. The fact that outbred pairs were more fertile than inbred pairs strongly supports the adaptive value of this mating system, which includes no "best phenotype" as the quality of two mating partners is primarily linked to their relatedness. We discuss the implications of our results in the light of inbreeding conflict models.

  1. Subsocial Cockroaches Nauphoeta cinerea Mate Indiscriminately with Kin Despite High Costs of Inbreeding

    Science.gov (United States)

    Bouchebti, Sofia; Durier, Virginie; Pasquaretta, Cristian; Rivault, Colette; Lihoreau, Mathieu

    2016-01-01

    Many animals have evolved strategies to reduce risks of inbreeding and its deleterious effects on the progeny. In social arthropods, such as the eusocial ants and bees, inbreeding avoidance is typically achieved by the dispersal of breeders from their native colony. However studies in presocial insects suggest that kin discrimination during mate choice may be a more common mechanism in socially simpler species with no reproductive division of labour. Here we examined this possibility in the subsocial cockroach Nauphoeta cinerea, a model species for research in sexual selection, where males establish dominance hierarchies to access females and control breeding territories. When given a binary choice between a sibling male and a non-sibling male that had the opportunity to establish a hierarchy prior to the tests, females mated preferentially with the dominant male, irrespective of kinship or body size. Despite the lack of kin discrimination during mate choice, inbred-mated females incurred significant fitness costs, producing 20% less offspring than outbred-mated females. We discuss how the social mating system of this territorial cockroach may naturally limit the probability of siblings to encounter and reproduce, without the need for evolving active inbreeding avoidance mechanisms, such as kin recognition. PMID:27655156

  2. On the widespread capacity for, and functional significance of, extreme inbreeding in ferns.

    Science.gov (United States)

    Sessa, Emily B; Testo, Weston L; Watkins, James E

    2016-08-01

    Homosporous vascular plants utilize three different mating systems, one of which, gametophytic selfing, is an extreme form of inbreeding only possible in homosporous groups. This mating system results in complete homozygosity in all progeny and has important evolutionary and ecological implications. Ferns are the largest group of homosporous land plants, and the significance of extreme inbreeding for fern evolution has been a subject of debate for decades. We cultured gametophytes in the laboratory and quantified the relative frequencies of sporophyte production from isolated and paired gametophytes, and examined associations between breeding systems and several ecological and evolutionary traits. The majority of fern species studied show a capacity for gametophytic selfing, producing sporophytes from both isolated and paired gametophytes. While we did not follow sporophytes to maturity to investigate potential detrimental effects of homozygosity at later developmental stages, our results suggest that gametophytic selfing may have greater significance for fern evolution and diversification than has previously been realized. We present evidence from the largest study of mating behavior in ferns to date that the capacity for extreme inbreeding is prevalent in this lineage, and we discuss its implications and relevance and make recommendations for future studies of fern mating systems.

  3. Inbreeding and its effect on some productive traits in buffaloes of South Iran

    Directory of Open Access Journals (Sweden)

    B. Mahmoodi

    2010-02-01

    Full Text Available The buffalo is a native animal of Iran and there were 500,000 buffaloes in Iran that over 80 per cent of its population concentrated in the north and north- west (Azerbaijan province and 18 per cent in the south (Khuzestan province of the country. Buffaloes reread in rural condition as multi purpose animals in Khuzestan. For mating, farmer use owns herd sire also artificial insemination is limited in the rural condition that may be inbred animals so affect the production performance. The aim of this investigation was estimate the inbreeding coefficient and its affect on some production performance. Data of 200 herds were used from the record sheets of herds under recording program of Animal Breeding Center during period 1990 to 2002 in the Khuzestan province. These results showed mostly herds only one sir and rarely two sires have been used. Inbreeding coefficient was 25 percent in some progeny and high-inbred buffaloes had a low performance. According to results of this study it could be concluded that farmers to avoid inbreeding should use other herd sire and artificial insemination also practical recording scheme and genetically selection to genetic improvement should be included in buffaloes of Iran.

  4. Mutual mate choice: when it pays both sexes to avoid inbreeding.

    Directory of Open Access Journals (Sweden)

    Mathieu Lihoreau

    Full Text Available Theoretical models of sexual selection predict that both males and females of many species should benefit by selecting their mating partners. However, empirical evidence testing and validating this prediction is scarce. In particular, whereas inbreeding avoidance is expected to induce sexual conflicts, in some cases both partners could benefit by acting in concert and exerting mutual mate choice for non-assortative pairings. We tested this prediction with the gregarious cockroach Blattella germanica (L.. We demonstrated that males and females base their mate choice on different criteria and that choice occurs at different steps during the mating sequence. Males assess their relatedness to females through antennal contacts before deciding to court preferentially non-siblings. Conversely, females biased their choice towards the most vigorously courting males that happened to be non-siblings. This study is the first to demonstrate mutual mate choice leading to close inbreeding avoidance. The fact that outbred pairs were more fertile than inbred pairs strongly supports the adaptive value of this mating system, which includes no "best phenotype" as the quality of two mating partners is primarily linked to their relatedness. We discuss the implications of our results in the light of inbreeding conflict models.

  5. Severe Inbreeding and Small Effective Number of Breeders in a Formerly Abundant Marine Fish

    Science.gov (United States)

    O'Leary, Shannon J.; Hice, Lyndie A.; Feldheim, Kevin A.; Frisk, Michael G.; McElroy, Anne E.; Fast, Mark D.; Chapman, Demian D.

    2013-01-01

    In contrast to freshwater fish it is presumed that marine fish are unlikely to spawn with close relatives due to the dilution effect of large breeding populations and their propensity for movement and reproductive mixing. Inbreeding is therefore not typically a focal concern of marine fish management. We measured the effective number of breeders in 6 New York estuaries for winter flounder (Pseudopleuronectes americanus), a formerly abundant fish, using 11 microsatellite markers (6–56 alleles per locus). The effective number of breeders for 1–2 years was remarkably small, with point estimates ranging from 65–289 individuals. Excess homozygosity was detected at 10 loci in all bays (FIS = 0.169–0.283) and individuals exhibited high average internal relatedness (IR; mean = 0.226). These both indicate that inbreeding is very common in all bays, after testing for and ruling out alternative explanations such as technical and sampling artifacts. This study demonstrates that even historically common marine fish can be prone to inbreeding, a factor that should be considered in fisheries management and conservation plans. PMID:23762473

  6. Inbreeding affects sexual signalling in males but not females of Tenebrio molitor.

    Science.gov (United States)

    Pölkki, Mari; Krams, Indrikis; Kangassalo, Katariina; Rantala, Markus J

    2012-06-23

    In many species of animals, individuals advertise their quality with sexual signals to obtain mates. Chemical signals such as volatile pheromones are species specific, and their primary purpose is to influence mate choice by carrying information about the phenotypic and genetic quality of the sender. The deleterious effects of consanguineous mating on individual quality are generally known, whereas the effect of inbreeding on sexual signalling is poorly understood. Here, we tested whether inbreeding reduces the attractiveness of sexual signalling in the mealworm beetle, Tenebrio molitor, by testing the preferences for odours of inbred and outbred (control) individuals of the opposite sex. Females were more attracted to the odours produced by outbred males than the odours produced by inbred males, suggesting that inbreeding reduces the attractiveness of male sexual signalling. However, we did not find any difference between the attractiveness of inbred and outbred female odours, which may indicate that the quality of females is either irrelevant for T. molitor males or quality is not revealed through female odours.

  7. Severe inbreeding and small effective number of breeders in a formerly abundant marine fish.

    Directory of Open Access Journals (Sweden)

    Shannon J O'Leary

    Full Text Available In contrast to freshwater fish it is presumed that marine fish are unlikely to spawn with close relatives due to the dilution effect of large breeding populations and their propensity for movement and reproductive mixing. Inbreeding is therefore not typically a focal concern of marine fish management. We measured the effective number of breeders in 6 New York estuaries for winter flounder (Pseudopleuronectes americanus, a formerly abundant fish, using 11 microsatellite markers (6-56 alleles per locus. The effective number of breeders for 1-2 years was remarkably small, with point estimates ranging from 65-289 individuals. Excess homozygosity was detected at 10 loci in all bays (FIS = 0.169-0.283 and individuals exhibited high average internal relatedness (IR; mean = 0.226. These both indicate that inbreeding is very common in all bays, after testing for and ruling out alternative explanations such as technical and sampling artifacts. This study demonstrates that even historically common marine fish can be prone to inbreeding, a factor that should be considered in fisheries management and conservation plans.

  8. Meiotic recombination shapes precision of pedigree- and marker-based estimates of inbreeding.

    Science.gov (United States)

    Knief, U; Kempenaers, B; Forstmeier, W

    2017-03-01

    The proportion of an individual's genome that is identical by descent (GWIBD) can be estimated from pedigrees (inbreeding coefficient 'Pedigree F') or molecular markers ('Marker F'), but both estimators come with error. Assuming unrelated pedigree founders, Pedigree F is the expected proportion of GWIBD given a specific inbreeding constellation. Meiotic recombination introduces variation around that expectation (Mendelian noise) and related pedigree founders systematically bias Pedigree F downward. Marker F is an estimate of the actual proportion of GWIBD but it suffers from the sampling error of markers plus the error that occurs when a marker is homozygous without reflecting common ancestry (identical by state). We here show via simulation of a zebra finch and a human linkage map that three aspects of meiotic recombination (independent assortment of chromosomes, number of crossovers and their distribution along chromosomes) contribute to variation in GWIBD and thus the precision of Pedigree and Marker F. In zebra finches, where the genome contains large blocks that are rarely broken up by recombination, the Mendelian noise was large (nearly twofold larger s.d. values compared with humans) and Pedigree F thus less precise than in humans, where crossovers are distributed more uniformly along chromosomes. Effects of meiotic recombination on Marker F were reversed, such that the same number of molecular markers yielded more precise estimates of GWIBD in zebra finches than in humans. As a consequence, in species inheriting large blocks that rarely recombine, even small numbers of microsatellite markers will often be more informative about inbreeding and fitness than large pedigrees.

  9. DISSOLUTION OF IRRADIATED MURR FUEL ASSEMBLIES EFFECT OF INCREASED PURGE RATE AND CATALYST CONCENTRATION ON THE BATCH SIZE

    Energy Technology Data Exchange (ETDEWEB)

    Kyser, E.

    2010-07-22

    Flowsheets for the dissolution of aluminum-clad spent nuclear fuel have been proposed using 0.002 M mercuric nitrate catalyst in 5 to 6 M nitric acid. Previous calculations for flammable gas control during the dissolution of spent nuclear fuel have been extended to cover a range of dissolver purge rates from 40 to 55 scfm. A range of dissolver solution volumes from 12000 to 15000 liters were considered for the large H-Canyon dissolver (6.4D). Depending on the purge rate, anywhere from four to six bundles of MURR fuel can be initially charged to the dissolver (6.4D). For successive charges where the dissolver solution already contains 0.002 M mercury catalyst and the dissolved aluminum from five bundles of MURR fuel, five to nine bundles of additional fuel can be charged depending on the purge rate and the dissolver solution volume. Similar calculations have been performed for the small H-Canyon dissolver (6.1D) for solution volumes that ranged from 6000 to 7500 liters and purge rates from 40 to 55 scfm. The limitations on the initial charge are four to six bundles depending on the purge rate. The aluminum from four bundles of fuel in an initial charge will allow nine to ten bundles in the second charge to 6.1D depending on the purge rate and dissolver solution volume. Solubility or criticality limitations will restrict the second charge on the small dissolver. The concentration of aluminum from previous charges will slow the dissolution rate to extend the cycle time of repeated charges of fuel. Calculations have been performed to allow a second catalyst addition (up to 0.004 M total catalyst) to reduce the cycle time (as necessary) based on the aluminum concentration and the purge rate.

  10. The effect of sex-biased dispersal on opposite-sexed spatial genetic structure and inbreeding risk.

    Science.gov (United States)

    Blyton, Michaela D J; Banks, Sam C; Peakall, Rod

    2015-04-01

    Natal sex-biased dispersal has long been thought to reduce the risk of inbreeding by spatially separating opposite-sexed kin. Yet, comprehensive and quantitative evaluations of this hypothesis are lacking. In this study, we quantified the effectiveness of sex-biased dispersal as an inbreeding avoidance strategy by combining spatially explicit simulations and empirical data. We quantified the extent of kin clustering by measuring the degree of spatial autocorrelation among opposite-sexed individuals (FM structure). This allowed us to systematically explore how the extent of sex-biased dispersal, generational overlap, and mate searching distance, influenced both kin clustering, and the resulting inbreeding in the absence of complementary inbreeding avoidance strategies. Simulations revealed that when sex-biased dispersal was limited, positive FM genetic structure developed quickly and increased as the mate searching distance decreased or as generational overlap increased. Interestingly, complete long-range sex-biased dispersal did not prevent the development of FM genetic structure when generations overlapped. We found a very strong correlation between FM genetic structure and both FIS under random mating, and pedigree-based measures of inbreeding. Thus, we show that the detection of FM genetic structure can be a strong indicator of inbreeding risk. Empirical data for two species with different life history strategies yielded patterns congruent with our simulations. Our study illustrates a new application of spatial genetic autocorrelation analysis that offers a framework for quantifying the risk of inbreeding that is easily extendable to other species. Furthermore, our findings provide other researchers with a context for interpreting observed patterns of opposite-sexed spatial genetic structure.

  11. Postpartum Depression

    Science.gov (United States)

    ... starts about 1–3 weeks after childbirth. What causes postpartum depression? Postpartum depression probably is caused by a combination ... better. Can antidepressants cause side effects? Antidepressants can ... If your depression worsens soon after starting medication or if you ...

  12. Caregiver Depression

    Science.gov (United States)

    ... will not sell or share your name. Caregiver Depression Tweet Bookmark this page | Email | Print Many caregivers ... depression See your doctor Treatment Coping Symptoms of depression Caregiving is hard — and can lead to feelings ...

  13. Space Station Environmental Control and Life Support System Purge Control Pump Assembly Modeling and Analysis

    Science.gov (United States)

    Schunk, R. Gregory; Hunt, Patrick L. (Technical Monitor)

    2001-01-01

    Preliminary results from a thermal/flow analysis of the Purge Control Pump Assembly (PCPA) indicate that pump performance (mass flow rate) is enhanced via cooling of the housing and lowering of the inlet vapor quality. Under a nominal operational profile (25% duty cycle or less), at the maximum motor dissipation, it appears that the peristaltic tubing temperature will still remain significantly below the expected UPA condenser temperature (78 F max versus approximately 105 F in the condenser) permitting condensation in the pump head.

  14. Cryogenic system with GM cryocooler for krypton, xenon separation from hydrogen-helium purge gas

    Energy Technology Data Exchange (ETDEWEB)

    Chu, X. X.; Zhang, D. X.; Qian, Y.; Liu, W. [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800 (China); Zhang, M. M.; Xu, D. [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190 (China)

    2014-01-29

    In the thorium molten salt reactor (TMSR), fission products such as krypton, xenon and tritium will be produced continuously in the process of nuclear fission reaction. A cryogenic system with a two stage GM cryocooler was designed to separate Kr, Xe, and H{sub 2} from helium purge gas. The temperatures of two stage heat exchanger condensation tanks were maintained at about 38 K and 4.5 K, respectively. The main fluid parameters of heat transfer were confirmed, and the structural heat exchanger equipment and cold box were designed. Designed concentrations after cryogenic separation of Kr, Xe and H{sub 2} in helium recycle gas are less than 1 ppb.

  15. Cryogenic system with GM cryocooler for krypton, xenon separation from hydrogen-helium purge gas

    Science.gov (United States)

    Chu, X. X.; Zhang, M. M.; Zhang, D. X.; Xu, D.; Qian, Y.; Liu, W.

    2014-01-01

    In the thorium molten salt reactor (TMSR), fission products such as krypton, xenon and tritium will be produced continuously in the process of nuclear fission reaction. A cryogenic system with a two stage GM cryocooler was designed to separate Kr, Xe, and H2 from helium purge gas. The temperatures of two stage heat exchanger condensation tanks were maintained at about 38 K and 4.5 K, respectively. The main fluid parameters of heat transfer were confirmed, and the structural heat exchanger equipment and cold box were designed. Designed concentrations after cryogenic separation of Kr, Xe and H2 in helium recycle gas are less than 1 ppb.

  16. Measurement of residual solvents in a drug substance by a purge-and-trap method.

    Science.gov (United States)

    Lakatos, Miklós

    2008-08-05

    The purge-and-trap (P&T) gas extraction method combined with gas chromatography was studied for its suitability for quantitative residual solvents determination in a water-soluble active pharmaceutical ingredient (API). Some analytical method performance characteristics were investigated, namely, the repeatability, the accuracy and the detection limit of determination. The results show that the P&T technique is--as expected--more sensitive than the static headspace, thus it can be used for the determination of residual solvents pertaining to the ICH Class 1 group. It was found that it could be an alternative sample preparation method besides the static headspace (HS) method.

  17. Apoptotic susceptibility to DNA damage of pluripotent stem cells facilitates pharmacologic purging of teratoma risk.

    Science.gov (United States)

    Smith, Alyson J; Nelson, Natalie G; Oommen, Saji; Hartjes, Katherine A; Folmes, Clifford D; Terzic, Andre; Nelson, Timothy J

    2012-10-01

    Pluripotent stem cells have been the focus of bioengineering efforts designed to generate regenerative products, yet harnessing therapeutic capacity while minimizing risk of dysregulated growth remains a challenge. The risk of residual undifferentiated stem cells within a differentiated progenitor population requires a targeted approach to eliminate contaminating cells prior to delivery. In this study we aimed to validate a toxicity strategy that could selectively purge pluripotent stem cells in response to DNA damage and avoid risk of uncontrolled cell growth upon transplantation. Compared with somatic cell types, embryonic stem cells and induced pluripotent stem cells displayed hypersensitivity to apoptotic induction by genotoxic agents. Notably, hypersensitivity in pluripotent stem cells was stage-specific and consistently lost upon in vitro differentiation, with the mean half-maximal inhibitory concentration increasing nearly 2 orders of magnitude with tissue specification. Quantitative polymerase chain reaction and Western blotting demonstrated that the innate response was mediated through upregulation of the BH3-only protein Puma in both natural and induced pluripotent stem cells. Pretreatment with genotoxic etoposide purged hypersensitive pluripotent stem cells to yield a progenitor population refractory to teratoma formation upon transplantation. Collectively, this study exploits a hypersensitive apoptotic response to DNA damage within pluripotent stem cells to decrease risk of dysregulated growth and augment the safety profile of transplant-ready, bioengineered progenitor cells.

  18. Purge and trap with monolithic sorbent for gas chromatographic analysis of pesticides in honey.

    Science.gov (United States)

    Chienthavorn, Orapin; Dararuang, Kanittha; Sasook, Anupop; Ramnut, Narumol

    2012-01-01

    Polydivinylbenzene (P-DVB) and silica monolithic materials were synthesised in capillaries and then used to adsorb nine organonitrogen pesticides extracted from honey. After adsorption, each monolith-capillary was connected to a gas chromatograph (GC) with nitrogen-phosphorous detector (NPD). The silica monolith gave better peak shape and intensity than the P-DVB monolith. Formulation of silica monolith with tetramethoxysilane (TMOS) as a sole initiator provided better separation and higher peak intensity, compared to those with methyltrimethoxysilane (MTMS) and (3:1) TMOS/MTMS initiators. The optimum internal diameter and length of silica monolith-capillary were 0.25 mm and 5 cm, respectively. The purge and trap conditions were optimised by purging with nitrogen and heating the honey sample solution at 100 °C for 60 min. Recovery of the method was in a range of 84.95-99.71% and the detection limits of the pesticides determined by using GC-NPD and GC-mass spectrometric detector (MSD) ranged between 0.36-1.75 and 0.13-0.25 ng g(-1), respectively.

  19. Determination of cyclic volatile methylsiloxanes in biota with a purge and trap method.

    Science.gov (United States)

    Kierkegaard, Amelie; Adolfsson-Erici, Margaretha; McLachlan, Michael S

    2010-11-15

    The three cyclic volatile methylsiloxanes (cVMS), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6), are recently identified environmental contaminants. Methods for the trace analysis of these chemicals in environmental matrices are required. A purge and trap method to prepare highly purified sample extracts with a low risk of sample contamination is presented. Without prior homogenization, the sample is heated in water, and the cVMS are purged from the slurry and trapped on an Isolute ENV+ cartridge. They are subsequently eluted with n-hexane and analyzed with GC/MS. The method was tested for eight different matrices including ragworms, muscle tissue from lean and lipid-rich fish, cod liver, and seal blubber. Analyte recoveries were consistent within and between matrices, averaging 79%, 68%, and 56% for D4, D5, and D6, respectively. Good control of blank levels resulted in limits of quantification of 1.5, 0.6, and 0.6 ng/g wet weight. The repeatability was 12% (D5) and 15% (D6) at concentrations 9 and 2 times above the LOQ. The method was applied to analyze cVMS in fish from Swedish lakes, demonstrating that contamination in fish as a result of long-range atmospheric transport is low as compared to contamination from local sources.

  20. Pedigree analysis of the Turkish Arab horse population: structure, inbreeding and genetic variability.

    Science.gov (United States)

    Duru, S

    2017-09-01

    The aim of this study was to evaluate genetic variability in the Turkish Arab horse population using pedigree information. This study is the first detailed pedigree analysis of the breed in Turkey. Pedigree data were collected from the National Studbook. The pedigree data for 23 668 horses, born between 1904 and 2014, were used in the analysis. From this data set, a reference population (RP) of 14 838 animals symbolising the last generation was defined. Demographic parameters, the inbreeding level (F), the average relatedness (AR), the effective population size (N e), the effective number of founders (f e), the effective number of ancestors (f a) and the number of founder genome equivalents (f g) were calculated for the population. The average generation interval for the RP was 12.2±4.6 years, whereas the calculated pedigree completeness levels were 98.2%, 96.6% and 95.0% for the first, second and third known generations. The mean equivalent generations (t), the average complete generations and the mean maximum generations for the RP were 7.8, 5.4 and 12.2, respectively, whereas the mean F and AR were 4.6% and 9.5% for the RP. The rate of inbred animals was 94.2% for the RP, whereas the number of founders, the number of ancestors and the f e, f a and f g were 342, 223, 40, 22 and 9.6 for the RP. The large differences observed between f e, and the number of founders demonstrates that genetic diversity decreased between the founder and the RP. Contribution of the 14 most influential founder to the RP was 50.0%, whereas just eight ancestral horses can account for 50% of the genetic variability. N e estimated via an individual increase in inbreeding per generation ( $$ \\hskip3pt{\\bar{\\hskip-2ptN}_{{\\rm e}} } $$ ), and paired increase in coancestry $$\\left(\\! \\hskip3pt{\\bar{\\hskip-2ptN}_{{ eC}} } \\right)$$ , were 74.4±3.9 and 73.5±0.58, respectively. The inbreeding increases with the pedigree knowledge. In addition, the decrease in inbreeding in last years

  1. Marker Assisted Selection can Reduce True as well as Pedigree Estimated Inbreeding

    DEFF Research Database (Denmark)

    Pedersen, L D; Sørensen, A C; Berg, P

    2009-01-01

    This study investigated whether selection using genotype information reduced the rate and level of true inbreeding, that is, identity by descent, at a selectively neutral locus as well as a locus under selection compared with traditional BLUP selection. In addition, the founder representation...... at these loci and the within-family selection at the nonneutral locus were studied. The study was carried out using stochastic simulation of a population resembling the breeding nucleus of a dairy cattle population for 25 yr. Each year, 10 proven bulls were selected across herds along with 100 dams from within...

  2. Inbreeding effects on palmar dermatoglyphic characters in three endogamous social groups of West Bengal, India.

    Science.gov (United States)

    Banik, S Datta

    2014-02-01

    The present study reports inbreeding effects on mean palmar dermatoglyphic characteristics: triradial count on palm, maximal atd angle, adt angle, td ridge count, ab ridge count, main line index (MLI) and ab ridge breadth. Samples were drawn from adult males belonging to three endogamous sections representing Hindu caste Telaga of Kharagpur (West Midnapore), Ansari Muslims of Nandigram (East Midnapore) and Sheik-Sunni Muslims of Braddhaman in West Bengal, India. Consistent trend of higher mean triradial number, adt angle, and lower mean td ridge count, ab ridge count, and ab ridge breadth was observed in inbred sections compared to their non-inbred relatives in three social groups.

  3. "Stolen" blood flow: effect of an open arterial filter purge line in a simulated neonatal CPB model.

    Science.gov (United States)

    Wang, Shigang; Miller, Akemi; Myers, John L; Undar, Akif

    2008-01-01

    The purpose of this study was to evaluate the effect of different flow rates and pressures on the degree of shunting of blood flow by the arterial filter purge line in a simulated neonatal cardiopulmonary bypass circuit. The circuit was primed with heparinized bovine blood (hematocrit 24%) and postfilter pressure was varied from 60-180 mm Hg (20 mm Hg increments) using a Hoffman clamp. Trials were conducted at flow rates ranging from 200-600 ml/min (100 ml/min increments). During trials conducted at a postfilter pressure of 60 mm Hg, 42.6% of blood flow was shunted through the purge line at a flow rate of 200 ml/min, whereas only 12.8% of flow was diverted at a flow rate 600 ml/min. During trials conducted at a postfilter pressure of 180 mm Hg, 82.8% of blood flow at 200 ml/min and 25.9% of blood flow at 600 ml/min was diverted through the open arterial purge line. The results of this study confirm that a significant amount of flow is diverted away from the patient when the arterial purge line is open. Shunting of blood flow through the arterial purge line could result in less effective tissue perfusion, particularly at low flow rates and high postfilter pressures. To minimize hypoperfusion injury, a flow probe (distal to the arterial filter) may be used to monitor real-time arterial flow in the setting of an open arterial filter purge line.

  4. Inbreeding and selection shape genomic diversity in captive populations: Implications for the conservation of endangered species.

    Science.gov (United States)

    Willoughby, Janna R; Ivy, Jamie A; Lacy, Robert C; Doyle, Jacqueline M; DeWoody, J Andrew

    2017-01-01

    Captive breeding programs are often initiated to prevent species extinction until reintroduction into the wild can occur. However, the evolution of captive populations via inbreeding, drift, and selection can impair fitness, compromising reintroduction programs. To better understand the evolutionary response of species bred in captivity, we used nearly 5500 single nucleotide polymorphisms (SNPs) in populations of white-footed mice (Peromyscus leucopus) to measure the impact of breeding regimes on genomic diversity. We bred mice in captivity for 20 generations using two replicates of three protocols: random mating (RAN), selection for docile behaviors (DOC), and minimizing mean kinship (MK). The MK protocol most effectively retained genomic diversity and reduced the effects of selection. Additionally, genomic diversity was significantly related to fitness, as assessed with pedigrees and SNPs supported with genomic sequence data. Because captive-born individuals are often less fit in wild settings compared to wild-born individuals, captive-estimated fitness correlations likely underestimate the effects in wild populations. Therefore, minimizing inbreeding and selection in captive populations is critical to increasing the probability of releasing fit individuals into the wild.

  5. Inbreeding levels in Northeast Brazil: strategies for the prospecting of new genetic disorders

    Directory of Open Access Journals (Sweden)

    Silvana Santos

    2010-01-01

    Full Text Available A new autosomal recessive genetic condition, the SPOAN syndrome (an acronym for spastic paraplegia, optic atrophy and neuropathy syndrome, was recently discovered in an isolated region of the State of Rio Grande do Norte in Northeast Brazil, in a population that was identified by the IBGE (Brazilian Institute of Geography and Statistics as belonging to the Brazilian communities with the highest rates of "deficiencies" (Neri, 2003, a term used to describe diseases, malformations, and handicaps in general. This prompted us to conduct a study of consanguinity levels in five of its municipal districts by directly interviewing their inhabitants. Information on 7,639 couples (corresponding to about 40% of the whole population of the studied districts was obtained. The research disclosed the existence of very high frequencies of consanguineous marriages, which varied from about 9% to 32%, suggesting the presence of a direct association between genetic diseases such as the SPOAN syndrome, genetic drift and inbreeding levels. This fact calls for the introduction of educational programs for the local populations, as well as for further studies aiming to identify and characterize other genetic conditions. Epidemiological strategies developed to collect inbreeding data, with the collaboration of health systems available in the region, might be very successful in the prospecting of genetic disorders.

  6. Glass Effect in Inbreeding-Avoidance Systems: Minimum Viable Population for Outbreeders

    Science.gov (United States)

    Tainaka, Kei-ichi; Itoh, Yoshiaki

    1996-10-01

    Many animals, birds and plants have evolved mechanisms to avoid inbreeding between close relatives.Such mating systems may have developed several methods for restricting mate choice.If fragmentation of habitats becomes serious, these methods may lead to a lack of acceptable mates. We call this “glass effect”which is a generalization of the so-called Allee effect.We present two inbreeding-avoidance (outbreeding) models.Both models show that outbreeders have a high risk infragmented environments.We thus obtain the minimum viable population (MVP). It is found that the value of MVP amounts to the range from several hundred to several thousand individuals.While this value is much larger than thoseobtained by the previous demographic theories,it is consistent with recent empirical estimations.Moreover, we find that the glass effect is caused bydynamically induced clusters of relatives.This suggests that genetic variation will be decreased by the outbreeding in a highly fragmented environment.

  7. Genetic Diversity of Three Aristichthys nobilis Populations and One Inbreeding Stock

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Genetic diversity of three Aristichthys nobilis populations and one inbreeding stock was studied using random amplified polymorphic DNA(RAPD)method. Materials of natural populations were collected from two counties of Guangxi Province, Hengxian (NH) and Shanglin (NS) and one city of Hubei Province, Wuhan city.(NW). Shanglin and Hengxian's river system respectively belongs to Qianjiang and Yujiang River, two tributaries confluencing to Xunjiang River, main tributary of Xijiang River, which is the biggest tributary of the Zhujiang River system, and Wuhan's water system belongs to the Yangtse River system. The inbreeding stock (RS) was the more than 10 generation descendant by brother-sister mating system whose parents were collected from Shanglin. The results showed that the genetic variety of individuals of RS was very low (0.105 4), whereas that of natural populations was relatively high,which from high to low was 0.158 1 (NW), 0.132 0 (NH) and 0.110 5 (NS). As an index for genetic distance pair-wise populations, the genetic variety between populations was studied, which characterized the genetic distance between populations. The genetic distance of NW and NH, NW and NS, NW and RS were respectively high, whereas that of NH and NS, NS and RS, NH and RS was low. Chi-test(χ2) and the analysis of the genetic variety pair-wise populations was taken as efficient approach for studying population difference.

  8. Inbreeding levels in Northeast Brazil: Strategies for the prospecting of new genetic disorders

    Science.gov (United States)

    2010-01-01

    A new autosomal recessive genetic condition, the SPOAN syndrome (an acronym for spastic paraplegia, optic atrophy and neuropathy syndrome), was recently discovered in an isolated region of the State of Rio Grande do Norte in Northeast Brazil, in a population that was identified by the IBGE (Brazilian Institute of Geography and Statistics) as belonging to the Brazilian communities with the highest rates of “deficiencies” (Neri, 2003), a term used to describe diseases, malformations, and handicaps in general. This prompted us to conduct a study of consanguinity levels in five of its municipal districts by directly interviewing their inhabitants. Information on 7,639 couples (corresponding to about 40% of the whole population of the studied districts) was obtained. The research disclosed the existence of very high frequencies of consanguineous marriages, which varied from about 9% to 32%, suggesting the presence of a direct association between genetic diseases such as the SPOAN syndrome, genetic drift and inbreeding levels. This fact calls for the introduction of educational programs for the local populations, as well as for further studies aiming to identify and characterize other genetic conditions. Epidemiological strategies developed to collect inbreeding data, with the collaboration of health systems available in the region, might be very successful in the prospecting of genetic disorders. PMID:21637472

  9. Inbreeding and selection on sex ratio in the bark beetle Xylosandrus germanus

    Directory of Open Access Journals (Sweden)

    Keller Laurent

    2011-12-01

    Full Text Available Abstract Background Local Mate Competition (LMC theory predicts a female should produce a more female-biased sex ratio if her sons compete with each other for mates. Because it provides quantitative predictions that can be experimentally tested, LMC is a textbook example of the predictive power of evolutionary theory. A limitation of many earlier studies in the field is that the population structure and mating system of the studied species are often estimated only indirectly. Here we use microsatellites to characterize the levels of inbreeding of the bark beetle Xylosandrus germanus, a species where the level of LMC is expected to be high. Results For three populations studied, genetic variation for our genetic markers was very low, indicative of an extremely high level of inbreeding (FIS = 0.88. There was also strong linkage disequilibrium between microsatellite loci and a very strong genetic differentiation between populations. The data suggest that matings among non-siblings are very rare (3%, although sex ratios from X. germanus in both the field and the laboratory have suggested more matings between non-sibs, and so less intense LMC. Conclusions Our results confirm that caution is needed when inferring mating systems from sex ratio data, especially when a lack of biological detail means the use of overly simple forms of the model of interest.

  10. Efecto de la endocría en caracteres relacionados con la calidad del fruto de zapallo Effect of inbreeding on the quality traits of squash fruit

    Directory of Open Access Journals (Sweden)

    Sanín Ortiz Grisales

    2009-07-01

    Full Text Available Se evaluó el rendimiento y características relacionados con la calidad del fruto de seis introducciones de zapallo, Cucurbita moschata Duch., a libre polinización (S0 y en las líneas endocriadas S1 y S2. La endocría acompañada de selección no causó efectos negativos en las variables producción por planta, espesor de la pulpa del fruto, color de la pulpa del fruto y materia seca en el fruto.Yield and related traits with fruit quality for six squash introductions Cucurbita moschata Duch. from open pollination (S0 and their respective inbreeding lines (S>1 and S2 was measured. It was determined that inbreed accompanied by selection didn't cause negative effects of depression in yield and agribusiness characteristic: plant production, wall fruit thickness , color of the fruit flesh and dry matter in fruit.

  11. Determination of phosphine: comparison of rates of desorption by purge-and-trap method and by sulfuric acid treatment.

    Science.gov (United States)

    Saeed, T; Abu-Tabanja, R

    1985-01-01

    Two methods were compared for quantitative determination of phosphine present on fumigated food and materials. The rate of desorption of PH3 by using a purge-and-trap method was shown to be much slower when compared with sulfuric acid treatment and was also simpler. Application of the modified sulfuric acid treatment for real samples is described.

  12. Influence of negative affect on decision making in women with restrictive and binge-purge type anorexia nervosa

    NARCIS (Netherlands)

    Danner, Unna N; Sternheim, Lot; Bijsterbosch, Jojanneke M; Dingemans, Alexandra E; Evers, Catharine; van Elburg, Annemarie A

    2016-01-01

    The present study aims to examine the influence of negative affect on decision making in women with anorexia nervosa (AN) compared to healthy control women and, secondly, to assess differences between the restrictive (ANR) and binge-purge (ANBP) subtypes. One hundred four women (32 with ANR, 32 with

  13. Purging deleterious mutations under self fertilization: paradoxical recovery in fitness with increasing mutation rate in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Levi T Morran

    Full Text Available BACKGROUND: The accumulation of deleterious mutations can drastically reduce population mean fitness. Self-fertilization is thought to be an effective means of purging deleterious mutations. However, widespread linkage disequilibrium generated and maintained by self-fertilization is predicted to reduce the efficacy of purging when mutations are present at multiple loci. METHODOLOGY/PRINCIPAL FINDINGS: We tested the ability of self-fertilizing populations to purge deleterious mutations at multiple loci by exposing obligately self-fertilizing populations of Caenorhabditis elegans to a range of elevated mutation rates and found that mutations accumulated, as evidenced by a reduction in mean fitness, in each population. Therefore, purging in obligate selfing populations is overwhelmed by an increase in mutation rate. Surprisingly, we also found that obligate and predominantly self-fertilizing populations exposed to very high mutation rates exhibited consistently greater fitness than those subject to lesser increases in mutation rate, which contradicts the assumption that increases in mutation rate are negatively correlated with fitness. The high levels of genetic linkage inherent in self-fertilization could drive this fitness increase. CONCLUSIONS: Compensatory mutations can be more frequent under high mutation rates and may alleviate a portion of the fitness lost due to the accumulation of deleterious mutations through epistatic interactions with deleterious mutations. The prolonged maintenance of tightly linked compensatory and deleterious mutations facilitated by self-fertilization may be responsible for the fitness increase as linkage disequilibrium between the compensatory and deleterious mutations preserves their epistatic interaction.

  14. Increases in frontostriatal connectivity are associated with response to dorsomedial repetitive transcranial magnetic stimulation in refractory binge/purge behaviors

    Directory of Open Access Journals (Sweden)

    Katharine Dunlop

    2015-01-01

    Conclusions: Enhanced frontostriatal connectivity was associated with responders to dmPFC-rTMS for binge/purge behavior. rTMS caused paradoxical suppression of frontostriatal connectivity in nonresponders. rs-fMRI could prove critical for optimizing stimulation parameters in a future sham-controlled trial of rTMS in disordered eating.

  15. Seasonal patterns of birth for subjects with bulimia nervosa, binge eating, and purging: results from the National Women's Study.

    Science.gov (United States)

    Brewerton, Timothy D; Dansky, Bonnie S; O'Neil, Patrick M; Kilpatrick, Dean G

    2012-01-01

    Studies of birth patterns in anorexia nervosa have shown relative increases between March and August, while studies in Bulimia Nervosa (BN) have been negative. Since there are no studies using representative, nonclinical samples, we looked for seasonal birth patterns in women with BN and in those who ever endorsed bingeing or purging. A national, representative sample of 3,006 adult women completed structured telephone interviews including screenings for bulimia nervosa (BN) and questions about month, date, and year of birth. Season of birth was calculated using traditional definitions. Differences across season of birth between subjects with (n = 85) and without BN (n = 2,898), those with (n = 749) and without bingeing (n = 2,229), and those with (n = 267) and without any purging (n = 2,715) were compared using chi-square analyses. There were significant differences across season of birth between subjects: (1) with and without BN (p = 0.033); (2) with and without bingeing (p = 0.034), and; (3) with and without purging (p = 0.001). Fall had the highest relative number of births for all categories, while spring had the lowest. In a national representative study of nontreatment seeking subjects significant differences in season of birth were found for subjects with lifetime histories of BN, binge eating and purging. © 2011 by Wiley Periodicals, Inc. (Int J Eat Disord 2012). Copyright © 2011 Wiley Periodicals, Inc.

  16. Enhanced selectivity of hyperthermic purging of human progenitor cells using Goralatide, an inhibitor of cell cycle progression

    NARCIS (Netherlands)

    Wierenga, PK; Brenner, MK; Konings, AWT

    1998-01-01

    Recurrence of leukemia is a major problem after autologous stem cell transplantation. One potential means of reducing this risk is to purge the autologous transplant in vitro by hyperthermia, We have demonstrated that after a hyperthermic treatment of 120 min at 43 degrees C, the leukemic progenitor

  17. Identification of Aroma Compounds of Lamiaceae Species in Turkey Using the Purge and Trap Technique

    Directory of Open Access Journals (Sweden)

    Ahmet Salih Sonmezdag

    2017-02-01

    Full Text Available The present research was planned to characterize the aroma composition of important members of the Lamiaceae family such as Salvia officinalis, Lavandula angustifolia and Mentha asiatica. Aroma components of the S. officinalis, L. angustifolia and M. asiatica were extracted with the purge and trap technique with dichloromethane and analyzed with the gas chromatography–mass spectrometry (GC–MS technique. A total of 23, 33 and 33 aroma compounds were detected in Salvia officinalis, Lavandula angustifolia and Mentha asiatica, respectively including, acids, alcohols, aldehydes, esters, hydrocarbons and terpenes. Terpene compounds were both qualitatively and quantitatively the major chemical group among the identified aroma compounds, followed by esters. The main terpene compounds were 1,8-cineole, sabinene and linalool in Salvia officinalis, Lavandula angustifolia and Mentha asiatica, respectively. Among esters, linalyl acetate was the only and most important ester compound which was detected in all samples.

  18. Identification of Aroma Compounds of Lamiaceae Species in Turkey Using the Purge and Trap Technique.

    Science.gov (United States)

    Sonmezdag, Ahmet Salih; Kelebek, Hasim; Selli, Serkan

    2017-02-08

    The present research was planned to characterize the aroma composition of important members of the Lamiaceae family such as Salvia officinalis, Lavandula angustifolia and Mentha asiatica. Aroma components of the S. officinalis, L. angustifolia and M. asiatica were extracted with the purge and trap technique with dichloromethane and analyzed with the gas chromatography-mass spectrometry (GC-MS) technique. A total of 23, 33 and 33 aroma compounds were detected in Salvia officinalis, Lavandula angustifolia and Mentha asiatica, respectively including, acids, alcohols, aldehydes, esters, hydrocarbons and terpenes. Terpene compounds were both qualitatively and quantitatively the major chemical group among the identified aroma compounds, followed by esters. The main terpene compounds were 1,8-cineole, sabinene and linalool in Salvia officinalis, Lavandula angustifolia and Mentha asiatica, respectively. Among esters, linalyl acetate was the only and most important ester compound which was detected in all samples.

  19. Identification of Aroma Compounds of Lamiaceae Species in Turkey Using the Purge and Trap Technique

    Science.gov (United States)

    Sonmezdag, Ahmet Salih; Kelebek, Hasim; Selli, Serkan

    2017-01-01

    The present research was planned to characterize the aroma composition of important members of the Lamiaceae family such as Salvia officinalis, Lavandula angustifolia and Mentha asiatica. Aroma components of the S. officinalis, L. angustifolia and M. asiatica were extracted with the purge and trap technique with dichloromethane and analyzed with the gas chromatography–mass spectrometry (GC–MS) technique. A total of 23, 33 and 33 aroma compounds were detected in Salvia officinalis, Lavandula angustifolia and Mentha asiatica, respectively including, acids, alcohols, aldehydes, esters, hydrocarbons and terpenes. Terpene compounds were both qualitatively and quantitatively the major chemical group among the identified aroma compounds, followed by esters. The main terpene compounds were 1,8-cineole, sabinene and linalool in Salvia officinalis, Lavandula angustifolia and Mentha asiatica, respectively. Among esters, linalyl acetate was the only and most important ester compound which was detected in all samples. PMID:28231089

  20. Spent nuclear fuel project cold vacuum drying facility vacuum and purge system design description

    Energy Technology Data Exchange (ETDEWEB)

    IRWIN, J.J.

    1998-11-30

    This document provides the System Design Description (SDD) for the Cold Vacuum Drying Facility (CVDF) Vacuum and Purge System (VPS) . The SDD was developed in conjunction with HNF-SD-SNF-SAR-O02, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of Processing Systems (Garvin 1998), The HNF-SD-SNF-DRD-002, 1998, Cold Vacuum Drying Facility Design Requirements, and the CVDF Design Summary Report. The SDD contains general descriptions of the VPS equipment, the system functions, requirements and interfaces. The SDD provides references for design and fabrication details, operation sequences and maintenance. This SDD has been developed for the SNFP Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved.

  1. [Recited depression].

    Science.gov (United States)

    Barucci, M; Cossio, M

    1984-01-01

    Several subjects who tell their depression and play a part of it in front of the doctor without being really depressed are reported. Some of them try to hide the symptoms (irritability or erethism, ceremonials of obsessive neurosis, shunning of phobia) which, in their opinion, might be detrimental to their reputation. Others neglect to describe some of the symptoms of their polymorphous clinical picture only underlining the depressive signs. Some others play a part of depression because they have believed to recognize themselves in persons presented by mass media, because it seems to them a duty to show an adequate depression in case of mournful event, or because they "convert" their problem into a depression. Some others use depression as a blackmail, or to obtain an advantage from doctor's conviction about their illness. The reason for the high frequency of similar cases in the present time are examined: the scientific divulgation and the acceptance of depression by the modern society are among the most important ones. The peculiar semantic vicissitudes of the word depression are also reviewed. A widening of the boundaries of depression has contributed to an increase in the number of the cases. Finally, in addition to patients who are depressed without being aware of it, the authors focus the inverse possibility: patients who believed or try to make their doctor believe (playing the part of depression in front of them) that they are depressed.

  2. Interplay between habitat fragmentation and climate change : inbreeding affects the response to thermal stress in Drosophila melanogaster

    NARCIS (Netherlands)

    Joubert, D.; Bijlsma, R.

    2010-01-01

    Climate change, exerting thermal stress, and habitat destruction and fragmentation, resulting in genetic drift and inbreeding, are amongst the most disturbing human activities that endanger global biodiversity. We studied the interplay between these 2 processes using Drosophila melanogaster as a mod

  3. Sex differences in the genetic architecture of lifespan in a seed beetle: extreme inbreeding extends male lifespan

    Directory of Open Access Journals (Sweden)

    Maklakov Alexei A

    2009-02-01

    Full Text Available Abstract Background Sex differences in lifespan are ubiquitous throughout the animal kingdom but the causes underlying this phenomenon remain poorly understood. Several explanations based on asymmetrical inheritance patterns (sex chromosomes or mitochondrial DNA have been proposed, but these ideas have rarely been tested experimentally. Alternatively, sexual dimorphism in lifespan could result from sex-specific selection, caused by fundamental differences in how males and females optimize their fitness by allocating resources into current and future reproduction. Results Here we used sex-specific responses to inbreeding to study the genetic architecture of lifespan and mortality rates in Callosobruchus maculatus, a seed beetle that shows sexual dimorphism in lifespan. Two independent assays revealed opposing sex-specific responses to inbreeding. The combined data set showed that inbred males live longer than outbred males, while females show the opposite pattern. Both sexes suffered reduced fitness measured as lifetime reproductive success as a result of inbreeding. Conclusion No model based on asymmetrical inheritance can explain increased male lifespan in response to inbreeding. Our results are however compatible with models based on sex-specific selection on reproductive strategies. We therefore suggest that sex-specific differences in lifespan in this species primarily result from sexually divergent selection.

  4. Deepening Our Understanding of Academic Inbreeding Effects on Research Information Exchange and Scientific Output: New Insights for Academic Based Research

    Science.gov (United States)

    Horta, Hugo

    2013-01-01

    This paper analyzes the impact of academic inbreeding in relation to academic research, and proposes a new conceptual framework for its analysis. We find that mobility (or lack of) at the early research career stage is decisive in influencing academic behaviors and scientific productivity. Less mobile academics have more inward oriented…

  5. Strategic promiscuity helps avoid inbreeding at multiple levels in a cooperative breeder where both sexes are philopatric

    NARCIS (Netherlands)

    Brouwer, Lyanne; van de Pol, Martijn; Atema, Els; Cockburn, Andrew

    2011-01-01

    In cooperative breeders, the tension between the opposing forces of kin selection and kin competition is at its most severe. Although philopatry facilitates kin selection, it also increases the risk of inbreeding. When dispersal is limited, extra-pair paternity might be an important mechanism to avo

  6. Atypical Depression

    Science.gov (United States)

    ... satisfaction and control in your life Help ease depression symptoms such as hopelessness and anger As part of your treatment, it's important to also address other conditions that often accompany atypical depression, in particular anxiety and drug or alcohol use, ...

  7. Teen Depression

    Science.gov (United States)

    ... Depression is a real, treatable brain illness, or health problem. Depression can be caused by big transitions in life, stress, or changes in your body’s chemicals that affect your thoughts and moods. Even if you feel ...

  8. Postpartum Depression

    Science.gov (United States)

    ... do not need treatment. The symptoms of postpartum depression last longer and are more severe. You may ... treatment right away, often in the hospital. Postpartum depression can begin anytime within the first year after ...

  9. Depression Treatment

    Science.gov (United States)

    ... 3286 After hours (404) 639-2888 Contact Media Depression Treatment Recommend on Facebook Tweet Share Compartir On ... How Do I Know if I Am Experiencing Depression? The following questions may help you determine if ...

  10. Depression Screening

    Science.gov (United States)

    ... Centers Diseases + Condition Centers Mental Health Medical Library Depression Screening (PHQ-9) - Instructions The following questions are ... this tool, there is also text-only version . Depression Screening - Manual Instructions The following questions are a ...

  11. Inbreeding in stochastic subdivided mating systems: the genetic consequences of host spatial structure, aggregated transmission dynamics and life history characteristics in parasite populations

    Indian Academy of Sciences (India)

    Guha Dharmarajan

    2015-03-01

    Inbreeding in parasite populations can have important epidemiological and evolutionary implications. However, theoretical models have predominantly focussed on the evolution of parasite populations under strong selection or in epidemic situations, and our understanding of neutral gene dynamics in parasite populations at equilibrium has been limited to verbal arguments or conceptual models. This study focusses on how host–parasite population dynamics affects observed levels of inbreeding in a random sample of parasites from an infinite population of hosts by bridging traditional genetic and parasitological processes utilizing a backward–forward branching Markov process embedded within a flexible statistical framework, the logarithmic-poisson mixture model. My results indicate that levels of inbreeding in parasites are impacted by demographic and/or transmission dynamics (subdivided mating, aggregated transmission dynamics and host spatial structure), and that this inbreeding is poorly estimated by ‘equilibrium’ levels of inbreeding calculated assuming regular systems of mating. Specifically, the model reveals that at low levels of inbreeding ( ≤ 0.1), equilibrium levels of inbreeding are lower than those observed, while at high levels of inbreeding the opposite pattern occurs. The model also indicates that inbreeding could have important epidemiological implications (e.g., the spread of recessive drug resistance genes) by directly impacting the observed frequency of rare homozygotes in parasite populations. My results indicate that frequencies of rare homozygotes are affected by aggregated transmission dynamics and host spatial structure, and also that an increase in the frequency of rare homozygotes can be caused by a decrease in effective population size solely due to the presence of a subdivided breeding system.

  12. Marker-assisted selection reduces expected inbreeding but can result in large effects of hitchhiking

    DEFF Research Database (Denmark)

    Pedersen, L D; Sørensen, A C; Berg, P

    2010-01-01

    We used computer simulations to investigate to what extent true inbreeding, i.e. identity-by-descent, is affected by the use of marker-assisted selection (MAS) relative to traditional best linear unbiased predictions (BLUP) selection. The effect was studied by varying the heritability (h2 = 0.04 vs....... 0.25), the marker distance (MAS vs. selection on the gene, GAS), the favourable QTL allele effect (α = 0.118 vs. 0.236) and the initial frequency of the favourable QTL allele (p = 0.01 vs. 0.1) in a population resembling the breeding nucleus of a dairy cattle population. The simulated genome...

  13. Shifts in reproductive assurance strategies and inbreeding costs associated with habitat fragmentation in Central American mahogany.

    Science.gov (United States)

    Breed, Martin F; Gardner, Michael G; Ottewell, Kym M; Navarro, Carlos M; Lowe, Andrew J

    2012-05-01

    The influence of habitat fragmentation on mating patterns and progeny fitness in trees is critical for understanding the long-term impact of contemporary landscape change on the sustainability of biodiversity. We examined the relationship between mating patterns, using microsatellites, and fitness of progeny, in a common garden trial, for the insect-pollinated big-leaf mahogany, Swietenia macrophylla King, sourced from forests and isolated trees in 16 populations across Central America. As expected, isolated trees had disrupted mating patterns and reduced fitness. However, for dry provenances, fitness was negatively related to correlated paternity, while for mesic provenances, fitness was correlated positively with outcrossing rate and negatively with correlated paternity. Poorer performance of mesic provenances is likely because of reduced effective pollen donor density due to poorer environmental suitability and greater disturbance history. Our results demonstrate a differential shift in reproductive assurance and inbreeding costs in mahogany, driven by exploitation history and contemporary landscape context.

  14. Inbreeding trends and pedigree analysis of Bavarian mountain hounds, Hanoverian hounds and Tyrolean hounds.

    Science.gov (United States)

    Voges, S; Distl, O

    2009-10-01

    The objective of this study was to analyse genetic diversity for the three scent-hound breeds Bavarian mountain hound (BMH), Hanoverian hound (HH) and Tyrolean hound (TH) using all available pedigree information from scent-hound kennel clubs for these three breeds throughout Europe. The pedigree data of the BMH and the HH date back to 1912 and 1894, respectively. Pedigree data of the TH were available from the 1960s onwards. The reference populations included all BMH (n = 3231), HH (n = 1371) and TH (n = 1167) dogs registered between 1992 and 2004. Average generation intervals were 5.3 years for the BMH and 5.0 years for the HH and TH. Average inbreeding coefficients for the reference populations were 4.5%, 6.8% and 9.5% for the BMH, HH and TH. The effective numbers of founders, ancestors and founder genomes were lowest for the TH and highest for the BMH. The effective numbers of founder genomes were 10.9, 5.6 and 4.3 for the BMH, HH and TH. Effective population size was largest for the BMH with 72.7 effective breeding animals, followed by the HH with 50.9 and TH with 26.5. The most important ten ancestors had genetic contributions to the reference populations of 54.4%, 65.2% and 77.9% in the BMH, HH and TH. The results of our study indicate the need for careful breed management in these highly specialized hound breeds to maintain genetic diversity. European stud books should be established for these dog breeds in order to avoid inbreeding due to missing pedigree records.

  15. Inbreeding depression in the partially self-incompatible endemic plant species Scalesia affinis (Asteraceae) from Galápagos islands

    DEFF Research Database (Denmark)

    Nielsen, L.R.; Siegismund, Hans Redlef; Hansen, T.

    2007-01-01

    Abstract  A previous study showed that some individuals of the tetraploid Galápagos endemic Scalesia affinis were able to produce offspring after selfing. The present study compares the fitness of self-pollinated offspring with the fitness of cross-pollinated offspring. Germination success, seedl...

  16. Analytical comparison and sensory representativity of SAFE, SPME, and Purge and Trap extracts of volatile compounds from pea flour.

    Science.gov (United States)

    Murat, Chloe; Gourrat, Karine; Jerosch, Heike; Cayot, Nathalie

    2012-12-01

    Pisum sativum is of great economic and nutritional interest due to its protein content. Nevertheless, pea products are underused as a protein source in human food because of their strong beany flavour. Therefore, the objective of this study was to select an efficient and representative method to extract volatile molecules of pea flour. In the first step, three extraction methods were chosen: solid phase micro extraction (SPME); Purge and Trap extraction and solvent assisted flavour evaporation (SAFE). The corresponding extracts were analysed by gas chromatography coupled with mass spectrometry. In the second step, the sensory representativity of the extracts was assessed either by direct gas chromatography-olfactometry for SPME and for Purge and Trap extracts, or by sniffing for the aqueous SAFE extract. It appeared that SAFE extraction was the most suitable method because of its good extraction capacities and its high sensory representativity of the global odour of pea flour.

  17. Spray chilling of deer carcasses--effects on carcass weight, meat moisture content, purge and microbiological quality.

    Science.gov (United States)

    Wiklund, E; Kemp, R M; leRoux, G J; Li, Y; Wu, G

    2010-12-01

    Twenty red deer carcasses were included in the study. Two treatments were applied to the carcasses; control (air chilling) and spray chilling (n=10 for each treatment). Carcass weight and temperature change were registered during over-night chilling. Meat moisture content was measured in the shoulder, loin, flap and leg before and after the chilling treatments; purge, cooking loss and tenderness were measured in loin samples stored at -1.5 °C for 3 and 9 weeks. Microbiological status was assessed on swabs taken at the lumbar end of the loin before and after the chilling treatments. Spray chilling reduced carcass weight loss significantly; air chilled and spray chilled carcasses lost 1 kg and less than 0.01 kg, respectively. No effects of spray chilling on tenderness, purge and cooking loss were found. Bacterial levels were low in general even after 9 weeks of vacuum packaged chilled storage.

  18. Study on purge gas generated in coke oven gas boilers mixing-firing process%焦炉气锅炉掺烧弛放气探讨

    Institute of Scientific and Technical Information of China (English)

    高翔

    2012-01-01

    It' s not an environmental friendly and economy way to discharged purge gas from methanol plant into the atmosphere. How to recycle methanol purge gas? The treatment of purge gas had been a general concern problem. The problem could be solved by incorpo- rating the decompression purge gas into boilers burning coke oven gas used as burning gas.%甲醇厂弛放气直接排人大气,既对环境产生污染,又无法实现经济价值。通过将弛放气减压掺入焦炉煤气中供锅炉燃烧使用的方法,可以解决弛放气的去向问题。

  19. Reduction of heat-induced haemotoxicity in a hyperthermic purging protocol of murine acute myeloid leukaemic stem cells by AcSDKP

    NARCIS (Netherlands)

    Wierenga, PK; Dillingh, JH; Konings, AWT

    1997-01-01

    The tetrapeptide AcSDKP (Goralatide) is a cytokine with known inhibitory effects on cell proliferation, Many purging agents used in autologous bone marrow transplantation protocols, including hyperthermia, preferentially kill cycling cells. A pretreatment with Goralatide offers a possibility to

  20. Unintended purge during the start-up process of a syringe pump: report of a case presented with vascular collapse.

    Science.gov (United States)

    Farbood, Arash; Kazemi, Asif Parviz; Akbari, Kamal

    2010-12-01

    The case of a 50 year-old woman who developed a sudden decrease in arterial pressure while she was being prepared for surgery for a fractured lumbar spine in the prone position, is reported. She was receiving propofol, remifentanil, and sodium nitroprusside via three syringe pumps through an intravenous cannula at the dorsum of her left hand. The cause of the vascular collapse was the purge of the syringe pumps during the self-check process.

  1. Prevalence of and Familial Influences on Purging Disorder in a Community Sample of Female Twins

    Science.gov (United States)

    Munn-Chernoff, Melissa A.; Keel, Pamela K.; Klump, Kelly L.; Grant, Julia D.; Bucholz, Kathleen K.; Madden, Pamela A. F.; Heath, Andrew C.; Duncan, Alexis E.

    2014-01-01

    Objective Purging Disorder (PD) was recently included as an Otherwise Specified Feeding or Eating Disorder (OSFED) in the DSM-5; however, limited information is available on its prevalence, and its etiology is unknown. Method Data from 1790 monozygotic and 1440 dizygotic European American female twins (age range = 18 – 29 years) from the Missouri Adolescent Female Twin Study were used to investigate prevalence and familial influences for PD. A structured clinical interview assessed lifetime DSM-IV criteria for eating disorders and PD. After adjustment for age, twin correlations and biometrical twin models were used to estimate familial (i.e., genetic plus shared environmental) influences on PD. Results One hundred and twenty one (3.77%; 95% CI: 3.14, 4.49) women met criteria for lifetime PD. Twin correlations suggested that genetic, shared environmental, and nonshared environmental factors influenced liability to PD. Nonshared environmental factors accounted for 56% [35%, 79%] of the variance in PD. Although familial effects accounted for a significant proportion of variance (44% [21%, 65%]), it was not possible to disentangle the independent contributions of additive genetic effects (20% [0%, 65%]) and shared environmental effects (24% [0%, 57%]). Discussion PD is a prevalent form of eating pathology. Familial factors are relevant to the development of PD but do not demonstrate the magnitude of heritable factors found for other eating disorders. PMID:25808399

  2. Numerical Simulation of Saline Intrusion and Purging in Long Sea Outfalls with Three-Dimensional Model

    Institute of Scientific and Technical Information of China (English)

    WU Wei; YAN Zhong-min; WU Long-hua

    2006-01-01

    Saline intrusion into marine sewage outfalls will greatly decrease the efficiency of sewage disposal. In order to investigate the mechanisms of this flow, in this paper, a three-dimensional numerical model based on FVM (Finite Volume Method) is established. The RNG k-ε model is selected for turbulence modeling. The time-averaged volume fraction equations are introduced to simulate the stratification and interfacial exchange of sewage and seawater in outfalls. Validity of the established three-dimensional numerical model is evaluated by comparisons of numerical results with experimental data. With this three-dimensional numerical model, the internal flow characteristics in outfalls for different sewage discharges are simulated. The results indicate that for a low sewage discharge, saline circulates in the outfall due to intrusion and both the inflowing momentum and the interfacial turbulent mixing are important mechanisms to extrude the saline. For a high sewage discharge, saline intrusion could be avoided. The inflow momentum is the main mechanism to extrude the saline and the interfacial turbulent mixing is not important relatively. Even at a high sewage discharge, the saline wedge would be retained in the main outfall pipe after the risers are purged. It takes a long time for this saline wedge to be extruded by interfacial turbulent mixing.

  3. Effect of self-purging pyrolysis on yield of biochar from maize cobs, husks and leaves.

    Science.gov (United States)

    Intani, Kiatkamjon; Latif, Sajid; Kabir, A K M Rafayatul; Müller, Joachim

    2016-10-01

    In this study, biochar was produced from maize residues (cobs, husks, leaves) in a lab-scale pyrolysis reactor without using a purging gas. The physicochemical properties of biomass and biochar were analysed. Box-Behnken design was used to optimise operational conditions for biochar yields. Multivariate correlations of biochar yields were established using reduced quadratic models with R(2)=0.9949, 0.9801 and 0.9876 for cobs, husks and leaves, respectively. Biochar yields were negatively correlated with the temperature, which was significantly influenced by the exothermic reactions during the pyrolysis of maize residues. The heating rate was found to have the least effect on biochar yields. Under optimal conditions, the maximum biochar yields from cobs, husks and leaves were 33.42, 30.69 and 37.91%, respectively. The highest biochar yield from maize leaves was obtained at a temperature of 300°C, a heating rate of 15°C/min and a holding time of 30min.

  4. Oncolytic viral purging of leukemic hematopoietic stem and progenitor cells with Myxoma virus.

    Science.gov (United States)

    Rahman, Masmudur M; Madlambayan, Gerard J; Cogle, Christopher R; McFadden, Grant

    2010-01-01

    High-dose chemotherapy and radiation followed by autologous blood and marrow transplantation (ABMT) has been used for the treatment of certain cancers that are refractory to standard therapeutic regimes. However, a major challenge with ABMT for patients with hematologic malignancies is disease relapse, mainly due to either contamination with cancerous hematopoietic stem and progenitor cells (HSPCs) within the autograft or the persistence of residual therapy-resistant disease niches within the patient. Oncolytic viruses represent a promising therapeutic approach to prevent cancer relapse by eliminating tumor-initiating cells that contaminate the autograft. Here we summarize an ex vivo "purging" strategy with oncolytic Myxoma virus (MYXV) to remove cancer-initiating cells from patient autografts prior to transplantation. MYXV, a novel oncolytic poxvirus with potent anti-cancer properties in a variety of in vivo tumor models, can specifically eliminate cancerous stem and progenitor cells from samples obtained from acute myelogenous leukemia (AML) patients, while sparing normal CD34+ hematopoietic stem and progenitor cells capable of rescuing hematopoiesis following high dose conditioning. We propose that a broader subset of patients with intractable hematologic malignancies who have failed standard therapy could become eligible for ABMT when the treatment schema is coupled with ex vivo oncolytic therapy.

  5. Microstructure and physical properties of steel-ladle purging plug refractory materials

    Science.gov (United States)

    Long, Bin; Xu, Gui-ying; Andreas, Buhr

    2017-02-01

    Three different castables were prepared as steel-ladle purging-plug refractory materials: corundum-based low-cement castable (C-LCC), corundum-spinel-based low-cement castable (C-S-LCC), and no-cement corundum-spinel castable (C-S-NCC) (hydratable alumina ρ-Al2O3 bonded). The properties of these castables were characterized with regard to water demand/flow ability, cold crushing strength (CCS), cold modulus of rupture (CMoR), permanent linear change (PLC), apparent porosity, and hot modulus of rupture (HMoR). The results show the CCS/CMoR and HMoR of C-LCC and C-S-LCC are greater than those of the castable C-S-NCC. According to the microstructure analysis, the sintering effect and the bonding type of the matrix material differ among the three castables. The calcium hexaluminate (CA6) phase in the matrix of C-LCC enhances the cold and hot mechanical strengths. In the case of C-S-LCC, the CA6 and 2CaO·2MgO·14Al2O3 (C2M2A14) ternary phases generated from the matrix can greatly increase the cold and hot mechanical strengths. In the case of the no-cement castable, sintering becomes difficult, resulting in a lower mechanical strength.

  6. Desalination of simulated seawater by purge-air pervaporation using an innovative fabricated membrane.

    Science.gov (United States)

    Naim, Mona; Elewa, Mahmoud; El-Shafei, Ahmed; Moneer, Abeer

    2015-01-01

    An innovative polymeric membrane has been invented, which presents a breakthrough in the field of desalination membranes. It can desalinate simulated seawater of exceptionally high concentration to produce a high flux of potable water with over 99.7% salt rejection (%SR) in a once-through purge-air pervaporation (PV) process. A set-up was constructed for conducting the desalination experiments and the effect of initial salt solution concentration (Ci) and pervaporation temperature (Tpv) on the water flux (J), %SR, separation factor, and pervaporation separation index were determined. The membrane was prepared by the phase-inversion technique, of a specially formulated casting solution consisting of five ingredients, after which the membrane was subjected to a post-treatment by which certain properties were conferred. The results confirmed that the salinity of the pervaporate was independent of Ci (all %SR above 99.7). The best result was at Tpv=70 °C, where J varied from 5.97 to 3.45 l/m2 h for Ci=40-140 g NaCl/l, respectively. The membrane morphology was confirmed to be asymmetric. The contact angle was immeasurable, indicating the membrane to be super-hydrophilic. Activation energies computed using Arrhenius law were, under all conditions investigated, less than 20 kJ/mol K.

  7. Adaptation to a new environment allows cooperators to purge cheaters stochastically.

    Science.gov (United States)

    Waite, Adam James; Shou, Wenying

    2012-11-20

    Cooperation via production of common goods is found in diverse life forms ranging from viruses to social animals. However, natural selection predicts a "tragedy of the commons": Cheaters, benefiting from without producing costly common goods, are more fit than cooperators and should destroy cooperation. In an attempt to discover novel mechanisms of cheater control, we eliminated known ones using a yeast cooperator-cheater system engineered to supply or exploit essential nutrients. Surprisingly, although less fit than cheaters, cooperators quickly dominated a fraction of cocultures. Cooperators isolated from these cocultures were superior to the cheater isolates they had been cocultured with, even though these cheaters were superior to ancestral cooperators. Resequencing and phenotypic analyses revealed that evolved cooperators and cheaters all harbored mutations adaptive to the nutrient-limited cooperative environment, allowing growth at a much lower concentration of nutrient than their ancestors. Even after the initial round of adaptation, evolved cooperators still stochastically dominated cheaters derived from them. We propose the "adaptive race" model: If during adaptation to an environment, the fitness gain of cooperators exceeds that of cheaters by at least the fitness cost of cooperation, the tragedy of the commons can be averted. Although cooperators and cheaters sample from the same pool of adaptive mutations, this symmetry is soon broken: The best cooperators purge cheaters and continue to grow, whereas the best cheaters cause rapid self-extinction. We speculate that adaptation to changing environments may contribute to the persistence of cooperative systems before the appearance of more sophisticated mechanisms of cheater control.

  8. Automatic heating and cooling system in a gas purge microsyringe extraction.

    Science.gov (United States)

    Piao, Xiangfan; Bi, Jinhu; Yang, Cui; Wang, Xiaoping; Wang, Juan; Li, Donghao

    2011-10-30

    The gas purge microsyringe extraction (GP-MSE) technique offers quantitative and simultaneous extraction, and rapid gas chromatographic-mass spectrometric determination of volatile and semivolatile chemicals is possible. To simplify the application, a new automatic temperature control system was developed here. Stable heating and cooling over a wide range of temperatures were achieved using a micro-heater and thermoelectric cooler under varying gas flow conditions. Temperatures could be accurately controlled in the range 20-350°C (heating) and 20 to -4°C (cooling). Temperature effects on the extraction performance of the GP-MSE were experimentally investigated by comparing the recoveries of polycyclic aromatic hydrocarbons (PAHs) under various experimental conditions. A sample treatment was completed within 3 min, which is much less than the time required for chromatographic analysis. The recovery of chemicals determined ranged from 81 to 96%. High reproducibility data (RSD ≤ 5%) were obtained for direct extraction of various analytes in spiked complex plant and biological samples. The data show that the heating and cooling system has potential applications in GP-MSE system for the direct determination of various kinds of volatile and semivolatile chemicals from complex matrices without any, or only minor, sample pretreatment.

  9. Analysis of ammonia separation from purge gases in microporous hollow fiber membrane contactors.

    Science.gov (United States)

    Karami, M R; Keshavarz, P; Khorram, M; Mehdipour, M

    2013-09-15

    In this study, a mathematical model was developed to analyze the separation of ammonia from the purge gas of ammonia plants using microporous hollow fiber membrane contactors. A numerical procedure was proposed to solve the simultaneous linear and non linear partial differential equations in the liquid, membrane and gas phases for non-wetted or partially wetted conditions. An equation of state was applied in the model instead of Henry's law because of high solubility of ammonia in water. The experimental data of CO₂-water system in the literature was used to validate the model due to the lack of data for ammonia-water system. The model showed that the membrane contactor can separate ammonia very effectively and with recoveries higher than 99%. SEM images demonstrated that ammonia caused some micro-cracks on the surfaces of polypropylene fibers, which could be an indication of partial wetting of membrane in long term applications. However, the model results revealed that the membrane wetting did not have significant effect on the absorption of ammonia because of very high solubility of ammonia in water. It was also found that the effect of gas velocity on the absorption flux was much more than the effect of liquid velocity.

  10. The Association of Inbreeding With Lung Fibrosis Incidence in Beagle Dogs That Inhaled 238PuO2 or 239PuO2.

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Dulaney A.; Brigantic, Andrea M.; Morgan, William F.

    2011-09-12

    Studies of health effects in animals after exposure to internally deposited radionuclides were intended to supplement observational studies in humans. Both nuclear workers and Beagle dogs have exhibited plutonium associated lung fibrosis; however, the dogs smaller gene pool may limit the applicability of findings to humans. Data on Beagles that inhaled either plutonium-238 dioxide (238PuO2) or plutonium-239 dioxide (239PuO2) were analyzed. Wright's Coefficient of Inbreeding was used to measure genetic or familial susceptibility and was assessed as an explanatory variable when modeling the association between lung fibrosis incidence and plutonium exposure. Lung fibrosis was diagnosed in approximately 80% of the exposed dogs compared with 23.7% of the control dogs. The maximum degree of inbreeding was 9.4%. Regardless of isotope, the addition of inbreeding significantly improved the model in female dogs but not in males. In female dogs an increased inbreeding coefficient predicted decreased hazard of a lung fibrosis diagnosis. Lung fibrosis was common in these dogs with inbreeding affecting models of lung fibrosis incidence in females but not in males. The apparent protective effect in females predicted by these models of lung fibrosis incidence is likely to be minimal given the small degree of inbreeding in these groups.

  11. Thermal Spray Using a High-Frequency Pulse Detonation Combustor Operated in the Liquid-Purge Mode

    Science.gov (United States)

    Endo, T.; Obayashi, R.; Tajiri, T.; Kimura, K.; Morohashi, Y.; Johzaki, T.; Matsuoka, K.; Hanafusa, T.; Mizunari, S.

    2016-02-01

    Experiments on thermal spray by pulsed detonations at 150 Hz were conducted. Two types of pulse detonation combustors were used, one operated in the inert gas purge (GAP) mode and the other in the liquid-purge (LIP) mode. In both modes, all gases were supplied in the valveless mode. The GAP mode is free of moving components, although the explosive mixture is unavoidably diluted with the inert gas used for the purge of the hot burned gas. In the LIP mode, pure fuel-oxygen combustion can be realized, although a liquid-droplet injector must be actuated cyclically. The objective of this work was to demonstrate a higher spraying temperature in the LIP mode. First, the temperature of CoNiCrAlY particles heated by pulsed detonations was measured. As a result, the spraying temperature in the LIP mode was higher than that in the GAP mode by about 1000 K. Second, the temperature of yttria-stabilized zirconia (YSZ) particles, whose melting point was almost 2800 °C, heated by pulsed detonations in the LIP mode was measured. As a result, the YSZ particles were heated up to about 2500 °C. Finally, a thermal spray experiment using YSZ particles was conducted, and a coating with low porosity was successfully deposited.

  12. Modeling and simulation of ammonia removal from purge gases of ammonia plants using a catalytic Pd-Ag membrane reactor.

    Science.gov (United States)

    Rahimpour, M R; Asgari, A

    2008-05-01

    In this work, the removal of ammonia from synthesis purge gas of an ammonia plant has been investigated. Since the ammonia decomposition is thermodynamically limited, a membrane reactor is used for complete decomposition. A double pipe catalytic membrane reactor is used to remove ammonia from purge gas. The purge gas is flowing in the reaction side and is converted to hydrogen and nitrogen over nickel-alumina catalyst. The hydrogen is transferred through the Pd-Ag membrane of tube side to the shell side. A mathematical model including conservation of mass in the tube and shell side of reactor is proposed. The proposed model was solved numerically and the effects of different parameters on the rector performance were investigated. The effects of pressure, temperature, flow rate (sweep ratio), membrane thickness and reactor diameter have been investigated in the present study. Increasing ammonia conversion was observed by raising the temperature, sweep ratio and reducing membrane thickness. When the pressure increases, the decomposition is gone toward completion but, at low pressure the ammonia conversion in the outset of reactor is higher than other pressures, but complete destruction of the ammonia cannot be achieved. The proposed model can be used for design of an industrial catalytic membrane reactor for removal of ammonia from ammonia plant and reducing NO(x) emissions.

  13. Needle-type extraction device for the purge and trap analysis of 23 volatile organic compounds in tap water.

    Science.gov (United States)

    Ueta, Ikuo; Razak, Nurhafizza Abd; Mizuguchi, Ayako; Kawakubo, Susumu; Saito, Yoshihiro; Jinno, Kiyokatsu

    2013-11-22

    We developed a rapid determination technique for trace volatile organic compounds (VOCs) in tap water by introducing a novel needle-type extraction device coupled to a purge-and-trap method. To extract a wide range of VOCs, a new extraction needle containing particles of divinylbenzene and activated carbon was developed in this study. During the active sampling of the headspace gas in a glass vial by the extraction needle, pure N2 gas was used for purging the aqueous sample. After the optimization of several experimental parameters, such as the addition of the salt and conditions of dry purging and desorption, the extraction performance of the device and method was evaluated for 23 VOCs that are typically found in tap water samples. The quantification limits of the method were 0.6 μg/L for 1,1-dichloroethylene and less than 0.5 μg/L for other VOCs, with good repeatability being confirmed for all the target compounds. Taking advantage of the excellent recovery of VOCs, the determination of VOCs in real tap water samples was carried out successfully. Because the developed method does not require sample heating and/or cryogenic focusing, simple and rapid analyses can be performed along with satisfactory sensitivity for typical tap water samples.

  14. Reciprocal associations between negative affect, binge eating, and purging in the natural environment in women with bulimia nervosa.

    Science.gov (United States)

    Lavender, Jason M; Utzinger, Linsey M; Cao, Li; Wonderlich, Stephen A; Engel, Scott G; Mitchell, James E; Crosby, Ross D

    2016-04-01

    Although negative affect (NA) has been identified as a common trigger for bulimic behaviors, findings regarding NA following such behaviors have been mixed. This study examined reciprocal associations between NA and bulimic behaviors using real-time, naturalistic data. Participants were 133 women with bulimia nervosa (BN) according to the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders who completed a 2-week ecological momentary assessment protocol in which they recorded bulimic behaviors and provided multiple daily ratings of NA. A multilevel autoregressive cross-lagged analysis was conducted to examine concurrent, first-order autoregressive, and prospective associations between NA, binge eating, and purging across the day. Results revealed positive concurrent associations between all variables across all time points, as well as numerous autoregressive associations. For prospective associations, higher NA predicted subsequent bulimic symptoms at multiple time points; conversely, binge eating predicted lower NA at multiple time points, and purging predicted higher NA at 1 time point. Several autoregressive and prospective associations were also found between binge eating and purging. This study used a novel approach to examine NA in relation to bulimic symptoms, contributing to the existing literature by directly examining the magnitude of the associations, examining differences in the associations across the day, and controlling for other associations in testing each effect in the model. These findings may have relevance for understanding the etiology and/or maintenance of bulimic symptoms, as well as potentially informing psychological interventions for BN. (c) 2016 APA, all rights reserved).

  15. Inbreeding and Gene Action in Butternut Squash (Cucurbita moschata Seed Starch Content / Endocría y Acción Génica para el Contenido Almidón en Semilla de Zapallo (Cucurbita moschata

    Directory of Open Access Journals (Sweden)

    Sanin Ortiz Grisales

    2014-03-01

    Full Text Available Abstract. The effect of inbreeding and gene action on butternutsquash (Cucurbita moschata Duch. seed production and seedstarch content was evaluated at two locations in the departmentof Valle del Cauca, Colombia, using six accessions (S0 and their inbred lines S1 and S2. Significant differences were found between the accessions and inbred lines, but not between localities. The seed production and seed starch content showed no significant effects of inbreeding depression. An additive-type gene action predominated, suggesting that recurrent selection could be the best strategy to increase the frequencies of genes promoting seed production and seed starch content. / Resumen. Se evaluó el efecto de la endocría y la acción génica en la producción de semilla y en el contenido de almidón en la semilla de zapallo (Cucurbita moschata Duch. en dos localidades del departamento del Valle del Cauca, Colombia, utilizando seis accesiones (S0 y sus respectivas líneas endocriadas S1 y S2. Se detectaron diferencias significativas entre accesiones y líneas endocriadas pero no entre localidades. La producción de semilla y el contenido de almidón no presentaron efectos significativos de depresión endogámica. Predominó la acción génica de tipo aditivo, sugiriendo que la selección recurrente podría ser la mejor estrategia para incrementar las frecuencias de los genes que favorecen la producción de semilla y contenido de almidón en la semilla.

  16. Regulation of purine biosynthetic genes expression in Salmonella typhimurium Ⅳ O~c mutation site of purG and its function analysis

    Institute of Scientific and Technical Information of China (English)

    刘奔; 黄谊; 王敖全

    1997-01-01

    Salmonella typhimurium 5 phosphoribosylformylglycinamide (FGAR) amidotransferase encoded by purG gene catalyzes the conversion of FGAR to formylglycinamide ribonucleotide (FGAM) in the presence of glu-tamine and ATP for the de novo purine nucleotide biosynthesis. purG gene is negatively regulated by a repressor-oper-ator system. The O+ purG and OC purG were cloned respectively in vivo. Restriction enzymes analysis of preliminary clones pLBG-1 (O + ) and pLBG-2 (OC) were carried out. The hybrid plasmids pLB1933 (O+ ) and pLB1927 (OC) containing 5 control region of purG were constructed and the DNA sequences were determined respectively. DNA se-quences data showed that Oc mutation of purG occurred at the 3rd position of 16 bp PUR box in the 5’ control region ( G→A). Gel retardation experiment indicated that the repressor bound well with O+ PUR box, but not with Oc PUR box. The result strongly supported the idea that PUR box is the binding region of represser protein and the 3rd posi-tion base G of PUR bo

  17. Inbreeding and genetic diversity analysis in a hatchery release population and clones of Rhopilema esculentum based on microsatellite markers

    Science.gov (United States)

    Tian, Tao; Chen, Zaizhong; Wang, Mosang; Hu, Yulong; Wang, Weiji

    2017-05-01

    Ten microsatellite markers were used to analyze the levels of genetic diversity and inbreeding in a hatchery release population of Rhopilema esculentum Kishinouye (Scyphozoa: Rhizostomatidae). A total of 85 alleles were detected in 600 individuals. Within-population levels of observed ( H o) and expected ( H e) heterozygosity ranged from 0.152 to 0.839 (mean=0.464) and from 0.235 to 0.821 (mean=0.618), respectively. The polymorphism information content (PIC) of each marker ranged from 0.207 to 0.795 with an average of 0.580, indicating that the hatchery population maintained a high level of genetic diversity. Inbreeding levels were estimated in the hatchery population and the inbreeding coefficient was 0.203. This result revealed that a certain level of inbreeding occurred within the population. Meanwhile, we also determined genetic diversity at the clone level. Several polyps from the same scyphistomae were genotyped at the ten microsatellite loci and there was virtually no difference in their genotypes. Furthermore, we calculated the probabilities of exclusion. When both parents were known, the average exclusion probability of ten loci was 99.99%. Our data suggest that the ten microsatellite markers can not only be used to analyze the identity of individuals but they can also be applied to parentage identification. Our research provides a theoretical basis and technical support for genetic diversity detection and reasonable selection of R. esculentum hatchery populations. These findings support the use of releasing studies and conservation of R. esculentum germplasm resources.

  18. Quality of the Exotic Parasitoid Cotesia flavipes (Hymenoptera: Braconidae) Does Not Show Deleterious Effects after Inbreeding for 10 Generations

    Science.gov (United States)

    Trevisan, Maíra; De Bortoli, Sergio A.; Vacari, Alessandra M.; Laurentis, Valéria L.; Ramalho, Dagmara G.

    2016-01-01

    Although the parasitoid Cotesia flavipes (Cameron) has proven effective in controlling sugarcane borer Diatraea saccharalis (Fabricius) for many years, concern has arisen over the quality of individuals produced at large scales. The parasitoid has been reared in laboratories in Brazil for more than 40 years, with no new introductions of new populations during that period. Since the quality of the parasitoids was not verified at the time of the species' introduction in Brazil, we do not know if there has been any reduction in quality so far. However, it is possible to determine whether the parasitoid could reduce in quality in future generations. Thus, the objective of this research was to assess the quality of these insects over 10 generations and look for evidence of any loss in quality. We used two populations: one from a biofactory that has been maintained in the laboratory for over 40 years, and an inbred laboratory population. Both were bred, and compared for 10 generations. We wanted to determine what happened to the quality of the parasitoid after 10 generations in an extreme inbreeding situation. To assure inbreeding, newly emerged females were forced to mate with a sibling. Individual females were then allowed to parasitize larvae of D. saccharalis. We performed evaluations for each generation until the tenth generation, and recorded the sex ratio, percentage emergence, number of offspring/females, and longevity of both males and females. Results of the measurements of biological characteristics demonstrated random significant differences between populations; best results were obtained intermittently for both the biofactory population and the inbred population. No significant differences across generations for the same population were observed. Thus, rearing of a C. flavipes population subjected to inbreeding for 10 generations was not sufficient to reveal any deleterious effects of inbreeding. PMID:27509087

  19. Inbreeding and genetic diversity analysis in a hatchery release population and clones of Rhopilema esculentum based on microsatellite markers

    Science.gov (United States)

    Tian, Tao; Chen, Zaizhong; Wang, Mosang; Hu, Yulong; Wang, Weiji

    2016-07-01

    Ten microsatellite markers were used to analyze the levels of genetic diversity and inbreeding in a hatchery release population of Rhopilema esculentum Kishinouye (Scyphozoa: Rhizostomatidae). A total of 85 alleles were detected in 600 individuals. Within-population levels of observed (H o) and expected (H e) heterozygosity ranged from 0.152 to 0.839 (mean=0.464) and from 0.235 to 0.821 (mean=0.618), respectively. The polymorphism information content (PIC) of each marker ranged from 0.207 to 0.795 with an average of 0.580, indicating that the hatchery population maintained a high level of genetic diversity. Inbreeding levels were estimated in the hatchery population and the inbreeding coefficient was 0.203. This result revealed that a certain level of inbreeding occurred within the population. Meanwhile, we also determined genetic diversity at the clone level. Several polyps from the same scyphistomae were genotyped at the ten microsatellite loci and there was virtually no difference in their genotypes. Furthermore, we calculated the probabilities of exclusion. When both parents were known, the average exclusion probability of ten loci was 99.99%. Our data suggest that the ten microsatellite markers can not only be used to analyze the identity of individuals but they can also be applied to parentage identification. Our research provides a theoretical basis and technical support for genetic diversity detection and reasonable selection of R. esculentum hatchery populations. These findings support the use of releasing studies and conservation of R. esculentum germplasm resources.

  20. Adaptation to a new environment allows cooperators to purge cheaters stochastically

    Science.gov (United States)

    Waite, Adam James; Shou, Wenying

    2012-01-01

    Cooperation via production of common goods is found in diverse life forms ranging from viruses to social animals. However, natural selection predicts a “tragedy of the commons”: Cheaters, benefiting from without producing costly common goods, are more fit than cooperators and should destroy cooperation. In an attempt to discover novel mechanisms of cheater control, we eliminated known ones using a yeast cooperator–cheater system engineered to supply or exploit essential nutrients. Surprisingly, although less fit than cheaters, cooperators quickly dominated a fraction of cocultures. Cooperators isolated from these cocultures were superior to the cheater isolates they had been cocultured with, even though these cheaters were superior to ancestral cooperators. Resequencing and phenotypic analyses revealed that evolved cooperators and cheaters all harbored mutations adaptive to the nutrient-limited cooperative environment, allowing growth at a much lower concentration of nutrient than their ancestors. Even after the initial round of adaptation, evolved cooperators still stochastically dominated cheaters derived from them. We propose the “adaptive race” model: If during adaptation to an environment, the fitness gain of cooperators exceeds that of cheaters by at least the fitness cost of cooperation, the tragedy of the commons can be averted. Although cooperators and cheaters sample from the same pool of adaptive mutations, this symmetry is soon broken: The best cooperators purge cheaters and continue to grow, whereas the best cheaters cause rapid self-extinction. We speculate that adaptation to changing environments may contribute to the persistence of cooperative systems before the appearance of more sophisticated mechanisms of cheater control. PMID:23091010

  1. Purge lecithin for less-expensive diet formulation for black tiger prawn Penaeus monodon

    Directory of Open Access Journals (Sweden)

    Shanmugam Velmurugan

    2010-12-01

    Full Text Available The knowledge of the nutrient requirements and practical diet formulations for Penaeus monodon is fully known. In the production cost, the cost of diet alone comes around 50 to70%. This ismainly because of the addition of lecithin which is a relatively expensive dietary ingredient. It isimportant to determine the usefulness of lecithin in the growth of P. monodon. In order to keep the dietcost as low as possible this experiment was designed with and without lecithin. The objective of thepresent study was to assess the growth of shrimp with varying lecithin doses. To study the water qualityparameters and to study the growth and survival of animals feed containing different percentage oflecithin. Trials conducted indicated the soybean lecithin did not have any effect on shrimp’s growth. Theshrimp weight varied from 3.15 to 8g in Control, 2.58 to 6g in Treatment A, 2.87 to 6.62g in TreatmentB, 3.1 to 6.75g in Treatment C. These confirm that under a controlled clear water culture system, partialor complete replacement of soybean lecithin in a commercial diet for P. monodon resulted in nodetriment in growth. Purge lecithin in the diet may allow for less-expensive diet formulations for P.monodon and may reduce the diet cost for producers, who are supplying feed. As diet cost representsthe largest variable cost in a commercial aquaculture operation, increased knowledge of specific dietaryrequirements is essential for formulating a cost-effective commercial P. monodon diet.

  2. Monitoring of phthalates in foodstuffs using gas purge microsyringe extraction coupled with GC-MS.

    Science.gov (United States)

    He, Miao; Yang, Cui; Geng, Renjie; Zhao, Xiangai; Hong, Lian; Piao, Xiangfan; Chen, Tie; Quinto, Maurizio; Li, Donghao

    2015-06-16

    Phthalate esters (PAEs) are commonly used as nonreactive plasticisers in vinyl plastics to increase the flexibility of plastic polymers. Numerous studies have indicated that the PAEs as a class of endocrine-disrupting chemicals. In addition, the studies have also shown that a major source of human exposure to phthalates is the diet. To date, the largest problem in PAEs analysis is the high blank value because PAEs are widely used in various applications and products. To overcome this shortcoming, gas purge microsyringe extraction (GP-MSE) was applied, which established a new and low-blank-value analytical method for PAE analysis to analyse PAEs in foodstuffs. In this study, GP-MSE was used as a clean-up method, and the overall recoveries ranged from 85.7 to 102.6%, and the RSD was less than 10%. More importantly, this method can overcome the problem of the high blank value in PAE analysis. This method was applied for measuring PAEs in 78 foodstuffs. The results showed that a wide variety of PAE concentrations were found in the different groups, and the content of PAEs (varies from 658 to 1610 ng g(-1) fresh weight) is greatest in seafood. The concentrations were in the following order: DEHP>DBP>DEP≈DMP>BBP≈DNOP. Finally, the daily intake of PAEs was estimated for adults based on the levels of PAEs in foodstuffs. The total EDIdiet values of 3.2 and 12.9 μg kg(-1) bw d(-1) were calculated for DEHP based on the mean and highest concentrations in foodstuffs, respectively.

  3. Inbreeding Ratio and Genetic Relationships among Strains of the Western Clawed Frog, Xenopus tropicalis.

    Directory of Open Access Journals (Sweden)

    Takeshi Igawa

    Full Text Available The Western clawed frog, Xenopus tropicalis, is a highly promising model amphibian, especially in developmental and physiological research, and as a tool for understanding disease. It was originally found in the West African rainforest belt, and was introduced to the research community in the 1990s. The major strains thus far known include the Nigerian and Ivory Coast strains. However, due to its short history as an experimental animal, the genetic relationship among the various strains has not yet been clarified, and establishment of inbred strains has not yet been achieved. Since 2003 the Institute for Amphibian Biology (IAB, Hiroshima University has maintained stocks of multiple X. tropicalis strains and conducted consecutive breeding as part of the National BioResource Project. In the present study we investigated the inbreeding ratio and genetic relationship of four inbred strains at IAB, as well as stocks from other institutions, using highly polymorphic microsatellite markers and mitochondrial haplotypes. Our results show successive reduction of heterozygosity in the genome of the IAB inbred strains. The Ivory Coast strains clearly differed from the Nigerian strains genetically, and three subgroups were identified within both the Nigerian and Ivory Coast strains. It is noteworthy that the Ivory Coast strains have an evolutionary divergent genetic background. Our results serve as a guide for the most effective use of X. tropicalis strains, and the long-term maintenance of multiple strains will contribute to further research efforts.

  4. The advantage of factorial mating under selection is uncovered by deterministically predicted rates of inbreeding

    Directory of Open Access Journals (Sweden)

    Sørensen Anders

    2005-01-01

    Full Text Available Abstract Rates of inbreeding (ΔF in selected populations were predicted using the framework of long-term genetic contributions and validated against stochastic simulations. Deterministic predictions decomposed ΔF into four components due to: finite population size, directional selection, covariance of genetic contribution of mates, and deviation of variance of family size from that expected from a Poisson distribution. Factorial (FM and hierarchical (HM mating systems were compared under mass and sib-index selection. Prediction errors were in most cases for ΔF less than 10% and for rate of gain less than 5%. ΔF was higher with index than mass selection. ΔF was lower with FM than HM in all cases except random selection. FM reduced the variance of the average breeding value of the mates of an individual. This reduced the impact of the covariance of contributions of mates on ΔF. Thus, contributions of mates were less correlated with FM than HM, causing smaller deviations of converged contributions from the optimum contributions. With index selection, FM also caused a smaller variance of number of offspring selected from each parent. This reduced variance of family size reduced ΔF further. FM increases the flexibility in breeding schemes for achieving the optimum genetic contributions.

  5. Linkage disequilibrium and the genetic distance in livestock populations: the impact of inbreeding

    Directory of Open Access Journals (Sweden)

    Baret Philippe V

    2004-05-01

    Full Text Available Abstract Genome-wide linkage disequilibrium (LD is subject to intensive investigation in human and livestock populations since it can potentially reveal aspects of a population history, permit to date them and help in fine-gene mapping. The most commonly used measure of LD between multiallelic loci is the coefficient D'. Data based on D' were recently published in humans, livestock and model animals. However, the properties of this coefficient are not well understood. Its sampling distribution and variance has received recent attention, but its expected behaviour with respect to genetic or physical distance remains unknown. Using stochastic simulations of populations having a finite size, we show that D' fits an exponential function having two parameters of simple biological interpretation: the residual value (rs towards which D' tends as the genetic distance increases and the distance R at which this value is reached. Properties of this model are evaluated as a function of the inbreeding coefficient (F. It was found that R and rs increase when F increases. The proposed model offers opportunities to better understand the patterns and the origins of LD in different populations and along different chromosomes.

  6. Adolescence depressions

    National Research Council Canada - National Science Library

    Matot, J P

    2009-01-01

    This article considers the depressive problematics emerging during adolescence in the frame of the transformations that characterize this period of life, with a focus on the interference of socio-cultural dimensions...

  7. Postpartum Depression

    DEFF Research Database (Denmark)

    Smith-Nielsen, Johanne

    Background: In three academic articles, this PhD thesis investigates maternal postpartum depression (PPD) as a risk factor for the infant-mother attachment and infant development. Previous studies have been contradictory with respect to the question of whether PPD can have long term effects...... on offspring. This may be due to not differing between when PPD is only occurring in the postpartum period and when effects are also due to ongoing or recurrent depression. However, it may also be due to viewing maternal depression as a unitary construct, and not considering underlying maternal psychological...... difficulties which may moderate potential adverse effects. The present thesis investigates two potential maternal moderators of risk:. Comorbid personality disorder and adult attachment insecurity. Moreover, the question of early environmental effects of PPD versus effects of later or ongoing depression...

  8. The Role of Non-Suicidal Self-Injury and Binge-Eating/Purging Behaviours in Family Functioning in Eating Disorders.

    Science.gov (United States)

    Depestele, Lies; Claes, Laurence; Dierckx, Eva; Baetens, Imke; Schoevaerts, Katrien; Lemmens, Gilbert M D

    2015-09-01

    This study aimed to investigate family functioning of restrictive and binge-eating/purging eating disordered adolescents with or without non-suicidal self-injury (NSSI), as perceived by the patients and their parents (mothers and fathers). In total, 123 patients (between 14 and 24 years), 98 mothers and 79 fathers completed the Family Assessment Device. Patients completed the Self-Injury Questionnaire-Treatment Related and the Symptom Checklist 90-Revised. No main effects were found of restrictive versus binge-eating/purging behaviour nor of presence/absence of NSSI. For the parents, a significant interaction between binge-eating/purging behaviour and NSSI emerged: Mothers and fathers reported worse family functioning in the binge-eating/purging group in presence of NSSI, whereas mothers reported worse family functioning in the restrictive group without NSSI. Parental perception of family functioning is affected by the combined presence of binge-eating/purging behaviour and NSSI. This finding should be taken into account when treating families living with eating disorders.

  9. Cardiac Risk and Disordered Eating: Decreased R Wave Amplitude in Women with Bulimia Nervosa and Women with Subclinical Binge/Purge Symptoms.

    Science.gov (United States)

    Green, Melinda; Rogers, Jennifer; Nguyen, Christine; Blasko, Katherine; Martin, Amanda; Hudson, Dominique; Fernandez-Kong, Kristen; Kaza-Amlak, Zauditu; Thimmesch, Brandon; Thorne, Tyler

    2016-11-01

    The purpose of the present study was threefold. First, we examined whether women with bulimia nervosa (n = 12) and women with subthreshold binge/purge symptoms (n = 20) showed decreased mean R wave amplitude, an indicator of cardiac risk, on electrocardiograph compared to asymptomatic women (n = 20). Second, we examined whether this marker was pervasive across experimental paradigms, including before and after sympathetic challenge tasks. Third, we investigated behavioural predictors of this marker, including binge frequency and purge frequency assessed by subtype (dietary restriction, excessive exercise, self-induced vomiting, and laxative abuse). Results of a 3 (ED symptom status) × 5 (experimental condition) mixed factorial ANCOVA (covariates: body mass index, age) indicated women with bulimia nervosa and women with subclinical binge/purge symptoms demonstrated significantly reduced mean R wave amplitude compared to asymptomatic women; this effect was pervasive across experimental conditions. Multiple regression analyses showed binge and purge behaviours, most notably laxative abuse as a purge method, predicted decreased R wave amplitude across all experimental conditions. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association.

  10. Critical role of a pre-purge setup in the thermal desorption analysis of volatile organic compounds by gas chromatography with mass spectrometry.

    Science.gov (United States)

    Kim, Yong-Hyun; Kim, Ki-Hyun

    2015-07-01

    In general, volatile organic compounds in ambient air are quantified by following a well-defined standard calibration procedure using a gas-/liquid-phase standard. If the liquid standard is analyzed by a thermal desorption, the solvent effect is unavoidable through the alteration of breakthrough properties or retention times. To learn more about the variables of the thermal desorption-based analysis, the effect of pre-purge conditions was evaluated for 18 volatile organic compounds with different types of sorbent tube materials by fixing standard volume (1 μL) and flow rate (100 mL/min). The gas phase calibration was also carried out as reference for the non-solvent effect. A single tube filled with Tenax TA exhibited the least solvent effect with the short pre-purge (1 min), while being subject to the breakthrough at or above 10 min pre-purge. For a three-bed sorbent tube with Carboxen 1000, at least 10 min of pre-purge was needed for the compounds with a retention time close to methanol (e.g., propanal). Another three-bed tube with Carbopack X reduced the solvent effect efficiently for a short pre-purge (2 min) without the breakthrough. As such, the solvent effect can be adjusted by the proper control of the sorbent tube application.

  11. 中韩石化武汉乙烯蒸汽管道吹扫分析%The Analysis of Purging Steam Pipe in SSWPC

    Institute of Scientific and Technical Information of China (English)

    唐旭

    2015-01-01

    The fundamental state of steam pipe network in the plant was introduced. A program for purging steam pipe was formulated with analysis of purging steam pipe theory and parameter estimates. Improvements were suggested to solve steam targeting problems and analyze reasons through the purging. It concluded that purging steam pipe theory and practical operation method were deeply understood, which was useful for similar purging pipe as a reference.%介绍我厂蒸汽管网概况,并对蒸汽吹扫原理和参数测算进行分析,制定吹扫方案。介绍我厂蒸汽管线吹扫的流程和吹扫中的问题和原因分析及解决措施。通过总结分析,加深对蒸汽吹扫理论和实际操作方法的认识,对于同类蒸汽管线吹扫具有参考意义。

  12. Service Situation and Improvement Measures of Purging Plug Brick for Steel Ladle%钢包用透气砖的使用及改进措施

    Institute of Scientific and Technical Information of China (English)

    杨幸福; 崔庆阳; 徐兵; 毛晓刚; 崔广进

    2012-01-01

    The service requirements and damage mechanism of the purging plug brick for steel ladle are analyzed, and the influencing factors for the service life of purging plug brick are analyzed and discussed from the design, the production process, the operating conditions and the smelting conditions. The measures of improving the use of the purging plug brick are put forward, and at the same time the safety of the purging plug brick should be ensured to avoid the abnormal ladle-to-ladle phenomenon, even breakout accident in using. And the development trend of the purging plug brick is discussed.%对钢包用透气砖的使用要求和损毁机理进行了分析,并从透气砖的设计、生产工艺、操作条件、冶炼条件等方面分析讨论了透气砖寿命的影响因素,提出了改善透气砖使用情况的措施,同时提出要保证透气砖的安全性,避免在使用的过程中出现非正常倒包现象,甚至漏钢事故.并对透气砖的发展方向进行了探讨.

  13. Inbreeding and building up small populations of stingless bees (Hymenoptera, Apidae

    Directory of Open Access Journals (Sweden)

    Paulo Nogueira-Neto

    2002-12-01

    Full Text Available A study of the viability of small populations of Hymenoptera is a matter of importance to gain a better zoological, ethological, genetical and ecological knowledge of these insects, and for conservation purposes, mainly because of the consequences to the survival of colonies of many species of bees, wasps, and ants. Based on the Whiting (1943 principle, Kerr & Vencovski (1982 presented a hypothesis that states that viable populations of stingless bees (Meliponini should have at least 40 colonies to survive. This number was later extended to 44 colonies by Kerr (1985. This would be necessary to avoid any substantial amount of homozygosis in the pair of chromosomic sexual loci, by keeping at least six different sexual gene alleles in a reproductive population. In most cases this would prevent the production of useless diploid males. However, several facts weigh against considering this as a general rule. From 1990 to 2001, 287 colony divisions were made, starting with 28 foundation colonies, in the inbreeding and population experiments with the Meliponini reported here. These experiments constitute the most extensive and longest scientific research ever made with Meliponini bees. In ten different experiments presented here, seven species (one with two subspecies of Meliponini bees were inbred in five localities inside their wide-reaching native habitats, and in two localities far away from these habitats. This was done for several years. On the whole, the number of colonies increased and the loss of colonies over the years was small. In two of these experiments, although these populations were far (1,000 km and 1,200 km from their native habitat, their foundation colonies were multiplied successfuly. It was possible to build up seven strong and three expanding medium populations, starting with one, two, three or even five colonies. However, in six other cases examined here, the Whiting (1943 principle and the hypothesis of Kerr & Vencovski (1982

  14. CONTRIBUTION OF MARITAL DISTANCE TO COMMUNITY INBREEDING, HOMOZYGOSIS, AND REPRODUCTIVE WASTAGE FOR RECESSIVELY INHERITED GENETIC DISORDERS IN MADHYA PRADESH, INDIA

    Directory of Open Access Journals (Sweden)

    R S Balgir

    2013-11-01

    Full Text Available Background: Recessively inherited genetic disorders such as sickle cell anemia and β-thalassemia are commonly encountered in heterozygous and homozygous form in India. These hemolytic disorders cause a high degree of reproductive wastage in vulnerable communities. Inbreeding is usually the mating between two related individuals. Homozygosis is antagonistic process of heterosis. Purpose: This study was aimed at finding reproductive outcome in carrier couples of sickle cell disease, and β-thalassemia in terms of reproductive wastage in relation to varied marital distance between partners in Madhya Pradesh. Methods: A total of 107 (35 and 72, respectively carrier couples of β-thalassemia major and sickle cell anemia with confirmed affected offspring after taking detailed reproductive history were studied following the standard methodology in a tertiary hospital in Central India during March 2010 to February 2013. Results: A majority of sickle cell and b-thalassemia carrier couples (77.8% and 65.7%, respectively had married within physical distance of radius less than 50 kms. away from their native places. It was found that as the marital distance between two carrier partners of above disorders decreases, the number of abortions, still-births, neonatal mortality, infant mortality, and mortality under 10 years age increases, and vice versa, implicating inbreeding and homozygosis. The overall reproductive wastage of 28.2% and 18.6% was recorded in carrier couples of sickle cell disease and β-thalassemia, respectively. Conclusions: Relative small population size clubbed with small marital distance leads to inbreeding resulting in homozygosity which increases chances of affected offspring by recessive or deleterious traits and contributes to decreased fitness of a couple or population in Central India.

  15. Moderate multiple parentage and low genetic variation reduces the potential for genetic incompatibility avoidance despite high risk of inbreeding.

    Directory of Open Access Journals (Sweden)

    Cristina Tuni

    Full Text Available BACKGROUND: Polyandry is widespread throughout the animal kingdom. In the absence of direct benefits of mating with different males, the underlying basis for polyandry is enigmatic because it can carry considerable costs such as elevated exposure to sexual diseases, physical injury or other direct fitness costs. Such costs may be balanced by indirect genetic benefits to the offspring of polyandrous females. We investigated polyandry and patterns of parentage in the spider Stegodyphus lineatus. This species experiences relatively high levels of inbreeding as a result of its spatial population structure, philopatry and limited male mating dispersal. Polyandry may provide an opportunity for post mating inbreeding avoidance that reduces the risk of genetic incompatibilities arising from incestuous matings. However, multiple mating carries direct fitness costs to females suggesting that genetic benefits must be substantial to counter direct costs. METHODOLOGY/PRINCIPAL FINDINGS: Genetic parentage analyses in two populations from Israel and a Greek island, showed mixed-brood parentage in approximately 50% of the broods. The number of fathers ranged from 1-2 indicating low levels of multiple parentage and there was no evidence for paternity bias in mixed-broods from both populations. Microsatellite loci variation suggested limited genetic variation within populations, especially in the Greek island population. Relatedness estimates among females in the maternal generation and potentially interacting individuals were substantial indicating full-sib and half-sib relationships. CONCLUSIONS/SIGNIFICANCE: Three lines of evidence indicate limited potential to obtain substantial genetic benefits in the form of reduced inbreeding. The relatively low frequency of multiple parentage together with low genetic variation among potential mates and the elevated risk of mating among related individuals as corroborated by our genetic data suggest that there are limited

  16. Niveles y efectos de la consanguinidad en variables de comportamiento durante la tienta y la lidia en dos ganaderías de reses bravas de Colombia Levels and effects of inbreeding on performance traits during tempt and fight from two fighting bull farms in Colombia

    Directory of Open Access Journals (Sweden)

    David Calero Quintero

    2010-04-01

    GUA were 6.6 and 5.8%; and 4.2 and 6%, respectively. Means and standard deviations of inbreeding in EGC and GUA were 4.9±6.6 and 4.2±4.2% for the all animals, 4.5±5.8 and 6.0±3.4% for the last time studied , and 10.6±5.8 and 6.51±3.5% taking in to account only those that were related. The effect of some variables with the inbreeding had positive effects in those responsible for the ‘toreabilidad’ and style, and depressive on the force of the animals. The current inbreeding in these populations is medium; however, mating should be planned for an appropriate handling and to reduce increases in inbreeding.

  17. 钢包用透气砖的研究与发展方向%Research and development direction of purging plug for ladle

    Institute of Scientific and Technical Information of China (English)

    常雅楠; 张玲; 邵子铭

    2016-01-01

    The effect of purging plug’s materials and structure on thermal shock resistance and slag resistance was summarized,and the research progress on the use of performance and damage mechanism was reviewed. Then the effect of argon blowing process on the work of purging plug was introduced,and the further research and developing trend of purging were proposed in this paper.%综述了透气砖的材质和结构对其抗热震稳定性和抗渣性的影响,以及透气砖在使用性能和损毁机理方面的研究进展,介绍了吹氩工艺对透气砖工作的影响,提出了钢包用透气砖耐火材料的可能的发展方向。

  18. Comparison of quarter-hourly on-line dynamic headspace analysis to purge-and-trap analysis of varying volatile organic compounds in drinking water sources.

    Science.gov (United States)

    Schnable, J G; Dussert, B; Suffet, I H; Hertz, C D

    1990-07-27

    On-line dynamic headspace analysis was refined for the quarter-hourly monitoring of select volatile organic compounds (VOCs) in ground and surface waters, for extended periods of time. Hourly comparisons were made to on-line purge-and-trap analysis, and to purge-and-trap analysis after sample preservation and storage. Variations in VOC concentrations of 6047% biweekly, 222% daily, 97% hourly, and 35% quarter-hourly were observable, with the 15-min cycle of the dynamic headspace analysis. The headspace analyzer had superior retention time stability, required less maintenance, and had 1/4 the analysis time as a typical purge-and-trap-gas chromatograph system used for hourly comparisons.

  19. Multi-channel purge and trap system coupled with ion chromatography for the determination of alkylamines in cosmetics.

    Science.gov (United States)

    Zhong, Zhixiong; Li, Gongke; Luo, Zhibin; Zhu, Binghui

    2012-02-17

    A new multi-channel purge and trap system coupled with ion chromatography for the determination of six alkylamines in cosmetics was developed. The proposed method, based on purge and trap of the volatile alkylamines, involved in a miniaturization and multi-channel integration of classical steam distillation and a simple approach for routine labs. The procedure was rapidly achieved within 10 min and the matrix interferences could be effectively eliminated. Sample pretreatment frequency was higher than 40 h(-1). The linear ranges were 0.1-15 mg L(-1) and the detection limits varied from 0.023 to 0.038 mg L(-1). This method was successfully utilized to determine the amounts of alkylamines in cosmetics with recoveries ranging from 80.3 to 105.5% and the relative standard deviations (RSDs) ranging from 0.78 to 7.5%. It was proved to be accurate, time-saving, and suitable for the determination of large numbers of cosmetics in a short time.

  20. A CFD Analysis of Hydrogen Leakage During On-Pad Purge in the ORION/ARES I Shared Volume

    Science.gov (United States)

    Ajmani, Kumud; Edwards, Daryl A.

    2011-01-01

    A common open volume is created by the stacking of the Orion vehicle onto the Ares I Upper Stage. Called the Shared Volume, both vehicles contribute to its gas, fluid, and thermal environment. One of these environments is related to hazardous hydrogen gas. While both vehicles use inert purge gas to mitigate any hazardous gas buildup, there are concerns that hydrogen gas may still accumulate and that the Ares I Hazardous Gas Detection System will not be sufficient for monitoring the integrated volume. This Computational Fluid Dynamics (CFD) analysis has been performed to examine these topics. Results of the analysis conclude that the Ares I Hazardous Gas Detection System will be able to sample the vent effluent containing the highest hydrogen concentrations. A second conclusion is that hydrogen does not accumulate under the Orion Service Module (SM) avionics ring as diffusion and purge flow mixing sufficiently dilute the hydrogen to safe concentrations. Finally the hydrogen concentrations within the Orion SM engine nozzle may slightly exceed the 1 percent volume fraction when the entire worse case maximum full leak is directed vertically into the engine nozzle.

  1. Theoretical Purge Factor Determination as a Control Strategy for Potential Mutagenic Impurities in the Synthesis of Drug Substances.

    Science.gov (United States)

    Kragelj Lapanja, Nevenka; Toplak Časar, Renata; Jurca, Sabina; Doljak, Bojan

    Mutagenic impurities (MIs) are of serious concern for pharmaceutical industry, regulatory agencies and public health. The first guideline addressing the control of genotoxic impurities (GTIs) dates back to 2006. Since then there have been several updates and refinements, which eventually resulted in the guideline, published by the International Conference on Harmonisation (ICH) in June 2014. The ICH M7 guideline, compared to previous ones, offers greater flexibility in terms of control strategies for GTIs in drug substances. More specifically, it describes a control strategy that relies on process controls in lieu of analytical testing which is based on understanding the process chemistry and process parameters that impact the levels of GTIs. This principle is adopted in the theoretical purge factor determination tool proposed by Teasdale et al. Several case studies applying the proposed theoretical purge factor determination tool were published in recent years. The results confirm the tool's good predictability of the extent to which the impurity is removed by the process. Hopefully, this approach will soon be released as an in-silico tool, generally accepted by the regulatory agencies.

  2. The pro-Franco purge of the primary teaching profession La depuración franquista del magisterio primario

    Directory of Open Access Journals (Sweden)

    Juan Manuel FERNÁNDEZ SORIA

    2013-09-01

    Full Text Available The purge of primary school teaching profession, like other groups, was an instrument of political repression organized and planned in order to establish, keep and legitimise the social-political «New Order» that aroze after the victory of Franco's army. There are three points to this article. The first point establishes the state of the question on the repressive nature and conditions in Franco's Spain. The repression adopted against the school teachers has its own quality: it is more preventive than punitive, trying with it to dissuade the pedagogue action of the teaching profession, a group who never had the confidence of the new regime nor the ideological mainstays which support it, including the catolical church. The second point tries to clear this mistrust, which goes back to the times of the Spanish Second Republic; in this mistrust the purge of the schoolteachers has its arguments. The third part studies the purge of Valencian schoolteachers, and analyses its political and social characteristics, concluding that an apolitical and scantily compromised group is purged essentially due to political accusations. Though the accusations were not harsh we can confirm the hypothesis of the preventive purge of the teaching profession, a group the Franco regime needed but kept by fear. The great lozers of this repression were not only the school teachers but the Spanish society itself. A society that saw how the new pedagogy under Franco's regime cut the progress that was finally underway only a few years prior.La purga de los maestros de escuela primaria, como la de otros grupos profesionales, fue un instrumento de la represión política organizada y planificada para establecer, conservar y legitimar el «nuevo orden» sociopolítico que se implanta después la victoria militar de Franco. En este artículo planteamos tres cuestiones. La primera realiza un estado de situación sobre la naturaleza de la represión y las condiciones de la Espa

  3. 富氮气调在储粮应用中的问题探讨%Discussion about the Problem of Grain Storage by Purging Nitroren

    Institute of Scientific and Technical Information of China (English)

    李云霄; 陈宏斌

    2012-01-01

    By analyzing the current some problems in grain storage by purging nitroren, it Propose a solution, that reduce the application cost and improve the economic efficiency of grain storage by purging nltroren.%通过分析现行富氮气调储粮过程中存在的某些问题,提出解决方案,降低富氮气调储粮运行成本,提高富氮气调储粮的经济效益。

  4. PEMFC cold-start performance after twice purge%二次吹扫条件下的PEMFC冷启动实验

    Institute of Scientific and Technical Information of China (English)

    罗马吉; 王芳芳; 刘威; 詹志刚

    2011-01-01

    通过使用干空气二次吹扫的方式对稳定工作后的质子交换膜燃料电池(PEMFC)单电池进行除水处理,考察了单电池经过吹扫除水操作后的除水量以及内阻变化过程,并研究了单电池经过吹扫除水处理后的常温启动性能以及-10℃下的冷启动性能.实验研究发现:单电池经过干空气二次吹扫处理后,可以在较短时间内经济有效地移除电池内的水,同时单电池的内阻升高.单电池经过干空气二次吹扫后常温启动性能下降,且随二次吹扫流量的增加而加剧,但未造成不可恢复的性能损失.适当的二次吹扫流量可以使电池成功冷启动.吹扫除水策略是优化PEMFC冷启动性能的关键因素之一.%Water in an operated proton exchange membrane fuel cell (PEMFC) was removed by twice purging with dry air. The weight of removed water and the process of resistance-change were investigated after the gas purging operation on the cell. The start-up performance of the cell in normal temperature and the cold start-up performance at -10 °C after purge were studied. The experimental results indicate that the water in a single cell can be removed in quite short time effectively and the cell electric resistance increase after twice purging. The start-up performance of the cells in normal temperature become deteriorated and get worse with the increased purging gas volume after twice purging, but the performance degradation can be recovered. Cold start-up of single cell can perform successfully by appropriate flow rate of twice purging. Purge strategy is one of the key points of optimizing fuel cell cold start-up performance.

  5. Can Lupus Cause Depression?

    Science.gov (United States)

    ... lupus Living well with lupus Can lupus cause depression? Life with lupus can be challenging. With symptoms ... treatable illness called clinical depression. Symptoms of Clinical Depression People are considered clinically depressed when they have ...

  6. Older Adults and Depression

    Science.gov (United States)

    ... find more information? Reprints Share Older Adults and Depression Download PDF Download ePub Order a free hardcopy ... depression need treatment to feel better. Types of Depression There are several types of depression. The most ...

  7. Depression and Multiple Sclerosis

    Science.gov (United States)

    ... Symptoms Depression Share this page Facebook Twitter Email Depression Depression Fatigue Walking (Gait) Difficulties Numbness or Tingling ... away from addictive substances such as alcohol. Clinical depression It’s important to distinguish between mild, everyday “blues” — ...

  8. Investigation of genetic diversity and inbreeding in a Japanese native horse breed for suggestions on its conservation.

    Science.gov (United States)

    Onogi, Akio; Shirai, Kouichi; Amano, Tomoko

    2017-07-21

    Because native breeds can serve as genetic resources for adapting to environment changes, their conservation is important for future agroecosystems. Using pedigree analysis, we investigated genetic diversity and inbreeding in Japanese Hokkaido native horses, which have adapted to a cold climate and roughage diet. Genetic diversity was measured as the number of founders and the effective number of founders, ancestors and genomes. All metrics imply a decrease in genetic diversity. A comparison of these metrics suggested that pedigree bottlenecks contributed more than did random gene losses to the reduction of genetic diversity. Estimates of marginal contributions of ancestors suggest that the bottlenecks arose mainly because related stallions had been used for breeding. A tendency for an increase in inbreeding coefficients was observed. F-statistics revealed that a small effective population size majorly contributed to this increase, although non-random mating in particular regions also contributed. Because the bottlenecks are thought to have reduced the effective population size, our results imply that mitigation of bottlenecks is important for conservation. To this end, breeding should involve genetically diverse stallions. In addition, to prevent non-random mating observed in particular regions, efforts should be made to plan mating with consideration of kinships. © 2017 Japanese Society of Animal Science.

  9. A study of inbreeding and kinship in intracranial aneurysms in the Saguenay Lac-Saint-Jean region (Quebec, Canada).

    Science.gov (United States)

    De Braekeleer, M; Pérusse, L; Cantin, L; Bouchard, J M; Mathieu, J

    1996-03-01

    The genealogies of 533 individuals with an intracranial aneurysm (IA) born in the Saguenay-Lac-Saint-Jean region, a geographically isolated area located in northeastern Quebec, were reconstructed using a population-based register. A control group consisting of three individuals of the same sex and born on the same day and in the same municipality than the IA patients was created; the genealogies of the 1599 controls were also reconstructed. The coefficients of inbreeding and kinship were calculated. Familial aggregation, i.e. the presence of IA in two or more first- to third-degree relatives, was also sought. The mean inbreeding coefficient was lower in the IA group than in the control group (7.92 x 10(-4) versus 10.04 x 10(-4)). The mean kinship coefficient was higher in the IA group than in the control group (2.17 x 10(-4) versus 1.55 x 10(-4)). Forty-eight IA patients (9.0%) were first-degree relatives compared to only 1.9% of the control individuals. The proportion of individuals showing familial aggregation was higher in the IA group than in the control group (29.8% and 18.6% respectively). These results strongly suggest that some IA are genetically determined in this population.

  10. 甲醇合成环路弛放气深度利用%Optimal utilization of purge gas from the synthesis loop of methanol plant

    Institute of Scientific and Technical Information of China (English)

    何洋

    2012-01-01

    For the problem that the purge gas from the synthesis loop of methanol plant wasn't utilized in high value, an optimal utilization of the purge gas to double its value was proposed, which was to separate all the components from the purge gas by cryogenic method for more valuable use. The proposed concept is valuable for promotion. Especially for the natural gas-based methanol coproduction plants, it could provide a good way for utilizing the purge gas better and also regulate the methanol output.%针对甲醇装置合成环路弛放气价值普遍未得到充分利用的问题,提出了将甲醇弛放气深冷分离提纯各组分,然后分别加以优化利用的思路,实现价值翻倍.同时,该思路也具有推广价值和借鉴意义.特别是针对以天然气为原料联产甲醇的化工企业来说,既可更好地利用弛放气,还可调节甲醇产量.

  11. Molecular purging of multiple myeloma cells by ex-vivo culture and retroviral transduction of mobilized-blood CD34+ cells

    Directory of Open Access Journals (Sweden)

    Corneo Gianmarco

    2007-07-01

    Full Text Available Abstract Background Tumor cell contamination of the apheresis in multiple myeloma is likely to affect disease-free and overall survival after autografting. Objective To purge myeloma aphereses from tumor contaminants with a novel culture-based purging method. Methods We cultured myeloma-positive CD34+ PB samples in conditions that retained multipotency of hematopoietic stem cells, but were unfavourable to survival of plasma cells. Moreover, we exploited the resistance of myeloma plasma cells to retroviral transduction by targeting the hematopoietic CD34+ cell population with a retroviral vector carrying a selectable marker (the truncated form of the human receptor for nerve growth factor, ΔNGFR. We performed therefore a further myeloma purging step by selecting the transduced cells at the end of the culture. Results Overall recovery of CD34+ cells after culture was 128.5%; ΔNGFR transduction rate was 28.8% for CD34+ cells and 0% for CD138-selected primary myeloma cells, respectively. Recovery of CD34+ cells after ΔNGFR selection was 22.3%. By patient-specific Ig-gene rearrangements, we assessed a decrease of 0.7–1.4 logs in tumor load after the CD34+ cell selection, and up to 2.3 logs after culture and ΔNGFR selection. Conclusion We conclude that ex-vivo culture and retroviral-mediated transduction of myeloma leukaphereses provide an efficient tumor cell purging.

  12. An investigation of the joint longitudinal trajectories of low body weight, binge eating, and purging in women with anorexia nervosa and bulimia nervosa.

    Science.gov (United States)

    Lavender, Jason M; De Young, Kyle P; Franko, Debra L; Eddy, Kamryn T; Kass, Andrea E; Sears, Meredith S; Herzog, David B

    2011-12-01

    To describe the longitudinal course of three core eating disorder symptoms-low body weight, binge eating, and purging-in women with anorexia nervosa (AN) and bulimia nervosa (BN) using a novel statistical approach. Treatment-seeking women with AN (n = 136) or BN (n = 110) completed the Eating Disorders Longitudinal Interval Follow-Up Evaluation interview every 6 months, yielding weekly eating disorder symptom data for a 5-year period. Semiparametric mixture modeling was used to identify longitudinal trajectories for the three core symptoms. Four individual trajectories were identified for each eating disorder symptom. The number and general shape of the individual trajectories was similar across symptoms, with each model including trajectories depicting stable absence and stable presence of symptoms as well as one or more trajectories depicting the declining presence of symptoms. Unique trajectories were found for low body weight (fluctuating presence) and purging (increasing presence). Conjunction analyses yielded the following joint trajectories: low body weight and binge eating, low body weight and purging, and binge eating and purging. The course of individual eating disorder symptoms among patients with AN and BN is highly variable. Future research identifying clinical predictors of trajectory membership may inform treatment and nosological research. Copyright © 2010 Wiley Periodicals, Inc.

  13. Differential neural correlates of set-shifting in the bingeing-purging and restrictive subtypes of anorexia nervosa : An fMRI study

    NARCIS (Netherlands)

    Van Autreve, Sara; De Baene, W.; Baeken, Chris; van Heeringen, Kees; Vancayseele, Nikita; Vervaet, Myriam

    2016-01-01

    In this study, possible differences in the neural correlates of set-shifting abilities between the restrictive (AN-R) and bingeing/purging (AN-BP) subtypes of anorexia nervosa have been explored. Three groups of participants performed a set-shifting task during functional magnetic resonance imaging:

  14. Inbreeding effects on reproductive outcome: a study based on a large sample from the endogamous Vadde of Kolleru Lake, Andhra Pradesh, India.

    Science.gov (United States)

    Reddy, B M

    1992-10-01

    Inbreeding effects on reproductive outcome vis-à-vis fertility, prenatal loss and prereproductive mortality, and secondary sex ratio of live and dead children were examined in a large sample of 2078 women of the Vadde fishing population of Kolleru Lake in Andhra Pradesh, India. Demographically, this population is a single endogamous unit. By using an exponential regression model with the proportion of offspring survival as a dependent variable and the inbreeding coefficient as an independent variable, I further examined the inbreeding effects. The results were compared with results from other fishing groups and other southern Indian and non-Indian populations. The results among the Vadde were consistent with those found for other groups of Telugu-speaking fishermen and several other southern Indian populations in that the effects were neither perceptible nor significant. The average B value and the number of lethal equivalents found for the highly inbred southern Indian populations in general and for the Vadde in particular were much smaller than those from other parts of the world, providing empirical support to Sanghvi's hypothesis on long-term effects of inbreeding.

  15. Adult nutrition, but not inbreeding, affects male primary sexual traits in the leaf-footed cactus bug Narnia femorata (Hemiptera: Coreidae).

    Science.gov (United States)

    Joseph, Paul N; Sasson, Daniel A; Allen, Pablo E; Somjee, Ummat; Miller, Christine W

    2016-07-01

    Adverse conditions may be the norm rather than the exception in natural populations. Many populations experience poor nutrition on a seasonal basis. Further, brief interludes of inbreeding can be common as population density fluctuates and because of habitat fragmentation. Here, we investigated the effects of poor nutrition and inbreeding on traits that can be very important to reproductive success and fitness in males: testes mass, sperm concentration, and sperm viability. Our study species was Narnia femorata, a species introduced to north-central Florida in the 1950s. This species encounters regular, seasonal changes in diet that can have profound phenotypic effects on morphology and behavior. We generated inbred and outbred individuals through a single generation of full-sibling mating or outcrossing, respectively. All juveniles were provided a natural, high-quality diet of Opuntia humifusa cactus cladode with fruit until they reached adulthood. New adult males were put on a high- or low-quality diet for at least 21 days before measurements were taken. As expected, the low-quality diet led to significantly decreased testes mass in both inbred and outbred males, although there were surprisingly no detectable effects on sperm traits. We did not find evidence that inbreeding affected testes mass, sperm concentration, and sperm viability. Our results highlight the immediate and overwhelming effects of nutrition on testes mass, while suggesting that a single generation of inbreeding might not be detrimental for primary sexual traits in this particular population.

  16. Calorie estimation accuracy and menu labeling perceptions among individuals with and without binge eating and/or purging disorders.

    Science.gov (United States)

    Roberto, Christina A; Haynos, Ann F; Schwartz, Marlene B; Brownell, Kelly D; White, Marney A

    2013-09-01

    Menu labeling is a public health policy that requires chain restaurants in the USA to post kilocalorie information on their menus to help consumers make informed choices. However, there is concern that such a policy might promote disordered eating. This web-based study compared individuals with self-reported binge eating disorder (N = 52), bulimia nervosa (N = 25), and purging disorder (N = 17) and those without eating disorders (No ED) (N = 277) on restaurant calorie information knowledge and perceptions of menu labeling legislation. On average, people answered 1.46 ± 1.08 questions correctly (out of 6) (25%) on a calorie information quiz and 92% of the sample was in favor of menu labeling. The findings did not differ based on eating disorder, dieting, or weight status, or race/ethnicity. The results indicated that people have difficulty estimating the calories in restaurant meals and individuals with and without eating disorders are largely in favor of menu labeling laws.

  17. A comparison of the metabolic complications and hospital course of severe anorexia nervosa by binge-purge and restricting subtypes.

    Science.gov (United States)

    Rylander, Melanie; Brinton, John T; Sabel, Allison L; Mehler, Philip S; Gaudiani, Jennifer L

    2017-01-06

    This study examines adult patients with severe, life-threatening anorexia nervosa who were admitted to an inpatient, medical stabilization unit between October 1, 2008 and December 31, 2014. Specifically, the study compares anorexia nervosa, binge purge subtype (AN-BP) and anorexia nervosa, restricting subtype (AN-R) on admission measures, hospital course, and outcomes. Of the 232 patients, 46% (N = 108) had AN-BP. Patients with AN-R manifested a higher frequency of underweight-mediated medical complications, including bone marrow dysfunction, hepatic dysfunction, and hypoglycemia. Understanding the pathophysiologic differences between severe AN-R and AN-BP is essential to understanding the abnormalities seen on clinical presentation, guiding appropriate clinical treatment, and predicting medical complications during refeeding.

  18. 推出增强的Purging Recorvery System大块清除料再生系统

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    美奎产品有限公司(以下简称“美奎”)近日宣布,该公司增强了其用于将大块清除料转变为再生料的Purging Recovery SystemTM(PRS),并且已经获得了在欧洲销售PRS所需的CE认证。美奎将会在NPE2012展会中重点推介PRS的新功能,并且提供数据来展示该系统可通过回收废品材料来快速收回投资成本。

  19. Determination of biodegradation process of benzene, toluene, ethylbenzene and xylenes in seabed sediment by purge and trap gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Han, Dongqiang [Key Lab. for Atomic and Molecular Nanosciences of Education Ministry, Tsinghua Univ., Beijing (China). Dept. of Physics; China Pharmaceutical Univ., Nanjing (China). Physics Teaching and Research Section, Dept. of Basic Sciences; Ma, Wanyun; Chen, Dieyan [Key Lab. for Atomic and Molecular Nanosciences of Education Ministry, Tsinghua Univ., Beijing (China). Dept. of Physics

    2007-12-15

    Benzene, toluene, ethylbenzene, and xylenes (BTEX) are commonly found in crude oil and are used in geochemical investigations as direct indicators of the presence of oil and gas. BTEX are easily volatile and can be degraded by microorganisms, which affect their precise measurement seriously. A method for determining the biodegradation process of BTEX in seabed sediment using dynamic headspace (purge and trap) gas chromatography with a photoionization detector (PID) was developed, which had a detection limit of 7.3-13.2 ng L{sup -1} and a recovery rate of 91.6-95.0%. The decrease in the concentration of BTEX components was monitored in seabed sediment samples, which was caused by microorganism biodegradation. The results of BTEX biodegradation process were of great significance in the collection, transportation, preservation, and measurement of seabed sediment samples in the geochemical investigations of oil and gas. (orig.)

  20. Evaluation of Capiox FX05 oxygenator with an integrated arterial filter on trapping gaseous microemboli and pressure drop with open and closed purge line.

    Science.gov (United States)

    Qiu, Feng; Peng, Sophia; Kunselman, Allen; Ündar, Akif

    2010-11-01

    Gaseous microemboli (GME) remain a challenge for cardiopulmonary bypass (CPB) because there is a positive correlation between microemboli exposure during CPB and postoperative neurological injury. Thus, minimizing the number of GME delivered to pediatric patients undergoing CPB procedures would lead to better clinical outcomes. In this study, we used a simulated CPB model to evaluate the effectiveness of capturing GME and the degree of membrane pressure drop for a new membrane oxygenator, Capiox Baby FX05 (Terumo Corporation,Tokyo, Japan), which has an integrated arterial filter with open and closed purge line.We used identical components in this study as our clinical CPB circuit. Three emboli detection and classification quantifier transducers were placed at prepump, preoxygenator, and postoxygenator sites in the circuit.Two flow probes as well as three pressure transducers were placed upstream and downstream of the oxygenator. The system was primed with human blood titrated to 30% hematocrit with Lactated Ringer’s solution.A bolus of air (1 mL) was injected in the prepump site under nonpulsatile perfusion mode at three flow rates (500,750, and 1000 mL/min) and with the purge line either open or closed. Six trials were performed for each unique set-up for a total of 36 trials.All trials were conducted at 35°C. The circuit pressure was kept constant at 100 mm Hg. Both the size and quantity of microemboli detected at postoxygenator site were recorded for 5 min postair injection. It was found that total counts of GME were significantly reduced with the purge line open when compared to keeping the purge line closed (P purge line closed compared to keeping the purge line open at flow rates of 750 mL/min and 1000 mL/min (P purge line open and closed, which is due to the small arteriovenous (A-V) shunt(P < 0.001). These results suggest that the integrated arterial filter of the Capiox FX05 oxygenator significantly improves the capturing of GME but has little impact on

  1. Increased survival of normal cells during laser photodynamic therapy: implications for ex vivo autologous bone marrow purging

    Energy Technology Data Exchange (ETDEWEB)

    Gulliya, K.S.; Matthews, J.L.; Fay, J.W.; Dowben, R.M.

    1988-01-01

    Laser light-induced, dye-mediated photolysis of leukemic cells was tested in an in vitro model for its efficacy in eliminating occult tumor cells for ex vivo autologous bone marrow purging. Merocyanine 540 (MC540) was mixed with acute promyelocytic leukemia (HL-60) cells in the presence of human albumin. This cell-dye mixture was irradiated with 514 nm argon laser light. Results show that in the presence of 0.1%, 0.25% and 0.5% albumin, laser light doses of 62.4 J/cm/sup 2/, 93.6 J/cm/sup 2/ and 109.2 J/cm/sup 2/, respectively, were required for a 5 log reduction in the survival of leukemic cells. Under identical conditions, 80% to 84% of the normal bone marrow cells and 41% of the granulocyte-macrophage colony forming cells survived. The number of surviving stromal cells was reduced (1+) compared to the untreated control (4+). Mixing of irradiated bone marrow cells with equal number of HL-60 cells did not interfere with the killing of HL-60 cells treated with MC540 and laser light. The non-specific cytotoxicity of laser light alone was less than 6% for normal bone marrow cells. These results suggest that the concentration of human albumin plays an important role in laser light-induced phototoxicity. This laser light-induced selective photolysis of leukemic cells can be used in ex vivo purging of tumor cell-contaminated bone marrow grafts to achieve very high survival rates of normal bone marrow cells and granulocyte-macrophage colony forming cells.

  2. Stress field distribution of purging plug for ladle in application process%钢包透气砖服役过程中应力分布研究

    Institute of Scientific and Technical Information of China (English)

    杨文刚; 刘国齐; 王建国; 于建宾; 马天飞; 钱凡

    2013-01-01

    The stress field distribution of purging plug during service was analyzed by ANSYS finite element software. The results are shown as follows. (l)The stress of purging plug is the highest at the argon blowing stage and reaches the maximum at the end of argon blowing;at this moment,the hot face of purging plug is mainly affected by radial and circumferential compressive stress,and the inside of purging plug is mainly affected by the radial,circumferential and axial tensile stress. (2)The damages of purging plug are mainly occurred in two parts:one is around slit in hot surface,as the compressive stress is large,which tends to produce cracks or spading;the other is 74 mm away from the hot face,as the tensile stress is large,which tends to cross-break.%利用Ansys有限元分析软件对钢包透气砖服役过程中的应力分布进行了研究.结果表明:透气砖在服役过程中,吹氩阶段所受热应力最大,在吹氩结束的瞬间达到最大值,此时透气砖工作面主要受径向和周向的压应力,透气砖内部主要受径向、周向和轴向的拉应力;透气砖损毁主要出现在两个部位,一是工作面狭缝周围由于压应力大易产生裂纹或者剥落,二是在距透气砖工作面74 mm的位置由于拉应力大易发生横断损毁.

  3. Testing the influence of family structure and outbreeding depression on heterozygosity-fitness correlations in small populations.

    Science.gov (United States)

    Jourdan-Pineau, Helene; Folly, Joy; Crochet, Pierre-Andre; David, Patrice

    2012-11-01

    Theory predicts that positive heterozygosity-fitness correlations (HFCs) arise as a consequence of inbreeding, which is often assumed to have a strong impact in small, fragmented populations. Yet according to empirical data, HFC in such populations seem highly variable and unpredictable. We here discuss two overlooked phenomena that may contribute to this variation. First, in a small population, each generation may consist of a few families. This generates random correlations between particular alleles and fitness (AFCs, allele-fitness correlations) and results in too liberal tests for HFC. Second, in some contexts, small populations receiving immigrants may be more impacted by outbreeding depression than by inbreeding depression, resulting in negative rather than positive HFC. We investigated these processes through a case study in tadpole cohorts of Pelodytes punctatus living in small ponds. We provide evidence for a strong family structure and significant AFC in this system, as well as an example of negative HFC. By simulations, we show that this negative HFC cannot be a spurious effect of family structure, and therefore reflects outbreeding depression in the studied population. Our example suggests that a detailed examination of AFC and HFC patterns can provide valuable insights into the internal genetic structure and sources of fitness variation in small populations.

  4. Inbreeding coefficients for X-linked and autosomal genes in consanguineous marriages in Spanish populations: the case of Guipúzcoa (Basque Country).

    Science.gov (United States)

    Calderón, R; Aresti, U; Ambrosio, B; González-Martín, A

    2009-03-01

    Inbreeding patterns over the past two centuries have been studied more extensively in Spain and Italy than anywhere else in Europe. Consanguinity studies in mainland Spain have shown that populations settled along the Cantabrian cornice share inbreeding patterns that distinguish them from other populations further south. A visual representation of spatial variations of two key inbreeding variables is presented here for the first time via contour maps. This paper also analyzes time trends of mean inbreeding coefficients for X-linked (F(x)) and autosomal genes (F) (1862-1995) together with variations in F(x)/F ratios in Guipúzcoa, the most autochthonous Spanish Basque province. Because close cousin marriages are a mark of identity of the study population, we evaluated the contribution of uncle-niece/aunt-nephew (M12) and first cousin (M22) marriages to F(x) and F values and compared the frequencies of M12 and M22 pedigree subtypes and their corresponding F(x)/F ratios to those found in other Spanish populations. The mean Fx and F inbreeding levels in Guipúzcoa for the 134-year period analyzed were 1.51 x 10(-3) and 1.04 x 10(-3), respectively, and the F(x)/F ratio was seen to be very stable over time. Our findings show that major similarities exist for close consanguineous marriage subtypes between Basque and non-Basque Spanish populations, despite significant geographic variability in terms of first cousin pedigrees. The distortion seems to be caused by Guipúzcoa. The F(x)/F ratios for first cousins in Spanish populations were higher than expected (1.25), with values ranging from 1.34 to 1.48. The findings of the present study may be useful for advancing knowledge on the effects of the interaction between biology and culture and for exploring associations between mating patterns and the prevalence of certain diseases.

  5. Helping your teen with depression

    Science.gov (United States)

    Teen depression - helping; Teen depression - talk therapy; Teen depression - medicine ... teen the most. The most effective treatments for depression are: Talk therapy Antidepressant medicines If your teen ...

  6. Distribution of individual inbreeding coefficients, relatedness and influence of stocking on native anadromous brown trout ( Salmo trutta ) population structure

    DEFF Research Database (Denmark)

    Ruzzante, D.E.; Hansen, Michael Møller; Meldrup, Dorte

    2001-01-01

    We examined polymorphism at seven microsatellite loci in 4023 brown trout (Salmo trutta) collected from 32 tributaries to the Limfjord, Denmark (similar to 200 km) and from two hatcheries used for stocking. Populations differ in their estimated sizes and stocking histories. Mean individual...... inbreeding coefficients do not differ among locations within rivers. Relatedness varies between sites within rivers indicating varied local dynamics at a very small geographical scale. Relatedness is sometimes lower than expected among an equal number of simulated individuals with randomized genotypes...... is true of the eastern, more heavily stocked, area of the Limfjord. Here, a higher proportion of the genetic variance is distributed among locations within rivers than among rivers. Assignment tests reveal that the majority of trout (mean 77% of all fish) are more probably of local origin than hatchery...

  7. What is depression?

    DEFF Research Database (Denmark)

    Davidsen, Annette Sofie; Fosgerau, Christina Fogtmann

    2014-01-01

    The diagnosis of depression is defined by psychiatrists, and guidelines for treatment of patients with depression are created in psychiatry. However, most patients with depression are treated exclusively in general practice. Psychiatrists point out that general practitioners' (GPs') treatment of ...

  8. Sadness and Depression

    Science.gov (United States)

    ... What Happens in the Operating Room? Sadness and Depression KidsHealth > For Kids > Sadness and Depression A A ... big difference in your life. When Sadness Is Depression When you're in a sad mood, it ...

  9. Depression Strikes…Anyone

    Science.gov (United States)

    ... of this page please turn JavaScript on. Feature: Depression Depression Strikes… Anyone Winter 2017 Table of Contents Anyone can suffer from depression. And almost everyone has a friend or family ...

  10. Depression and College Students

    Science.gov (United States)

    ... depression and other mental health issues? Reference Share Depression and College Students Download PDF Download ePub Order ... Answers to college students’ frequently asked questions about depression Feeling moody, sad, or grouchy? Who doesn’t ...

  11. Sadness and Depression

    Science.gov (United States)

    ... dientes Video: Getting an X-ray Sadness and Depression KidsHealth > For Kids > Sadness and Depression Print A ... big difference in your life. When Sadness Is Depression When you're in a sad mood, it ...

  12. Postpartum Depression Facts

    Science.gov (United States)

    ... Where can I find more information? Share Postpartum Depression Facts Download PDF Download ePub Download Mobi Order ... for herself or her family. What is postpartum depression? Postpartum depression is a mood disorder that can ...

  13. Recognizing teen depression

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000648.htm Recognizing teen depression To use the sharing features on this page, ... life. Be Aware of the Risk for Teen Depression Your teen is more at risk for depression ...

  14. Men and Depression

    Science.gov (United States)

    ... in crisis? For more information Share Men and Depression Download PDF Download ePub Order a free hardcopy ... If so, you may have depression. What is depression? Everyone feels sad or irritable sometimes, or has ...

  15. Various forms of depression

    OpenAIRE

    BENAZZI, FRANCO

    2006-01-01

    The current subtyping of depression is based on the Diagnostic and Statistical Manual of Mental Disorders, 4th ed. Text Revision (DSM-IV-TR) categorical division of bipolar and depressive disorders. Current evidence, however, supports a dimensional approach to depression, as a continuum/spectrum of overlapping disorders, ranging from bipolar I depression to major depressive disorder. Types of depression which have recently been the focus of most research will be reviewed ; bipolar II depressi...

  16. [Depressive symptoms and sexuality].

    Science.gov (United States)

    Porto, Robert

    2014-10-01

    The mutually reinforcing dyad of depressive symptoms and erectile dysfunction is scientifically established. The cure of depression improves sexual dysfunction (SD) and the treatment of SD induces improvement of depression. Most of anti-depressants induce negative sexual side effects that lead to non-compliance of these treatments. The knowledge of interrelation between depression, anti-depressants and sexuality is of great importance in clinical practice. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  17. Eating Disorders and Major Depression: Role of Anger and Personality

    Directory of Open Access Journals (Sweden)

    Abbate-Daga Giovanni

    2011-01-01

    Full Text Available This study aimed to evaluate comorbidity for MD in a large ED sample and both personality and anger as clinical characteristics of patients with ED and MD. We assessed 838 ED patients with psychiatric evaluations and psychometric questionnaires: Temperament and Character Inventory, Eating Disorder Inventory-2, Beck Depression Inventory, and State-Trait Anger Expression Inventory. 19.5% of ED patients were found to suffer from comorbid MD and 48.7% reported clinically significant depressive symptomatology: patients with Anorexia Binge-Purging and Bulimia Nervosa were more likely to be diagnosed with MD. Irritable mood was found in the 73% of patients with MD. High Harm Avoidance (HA and low Self-Directedness (SD predicted MD independently of severity of the ED symptomatology, several clinical variables, and ED diagnosis. Assessing both personality and depressive symptoms could be useful to provide effective treatments. Longitudinal studies are needed to investigate the pathogenetic role of HA and SD for ED and MD.

  18. The Role of Non-suicidal Self-Injury and Binge-Eating/Purging Behaviours in the Caregiving Experience Among Mothers and Fathers of Adolescents with Eating Disorders.

    Science.gov (United States)

    Depestele, Lies; Lemmens, Gilbert M D; Dierckx, Eva; Baetens, Imke; Schoevaerts, Katrien; Claes, Laurence

    2016-05-01

    This study investigated the caregiving experiences of mothers and fathers of restrictive and binge-eating/purging eating disordered (ED) inpatients with and without non-suicidal self-injury (NSSI). Sixty-five mothers and 65 fathers completed the Experience of Caregiving Inventory. All inpatients completed the Self-Injury Questionnaire-Treatment Related to assess NSSI and the Eating Disorder Evaluation Scale to assess eating disorder symptoms. Mothers reported significant more negative and more positive caregiving experiences compared with fathers. Mothers (but not fathers) of restrictive ED patients reported more positive caregiving experiences compared with mothers of binge-eating/purging patients. The presence of NSSI in ED patients was associated with more negative caregiving experiences of both parents. Mothers and fathers of ED inpatients differ in caregiving experiences, and both binge-eating behaviours and NSSI negatively affect their caregiving experience. Therefore, supportive interventions for parents of ED patients are necessary, especially of those patients who engage in NSSI.

  19. 聚丙烯料仓脱气压降算法研究%Research of Calculation Method for Pressure Drop in Purging of Polypropylene Silo

    Institute of Scientific and Technical Information of China (English)

    汪洋; 邢桂坤

    2015-01-01

    料仓脱气可以有效减少聚丙烯料仓闪爆事故的发生。介绍了聚丙烯粒料料仓脱气的工艺流程,着重论述了在颗粒床层的实际环境中料仓脱气压降的计算方法,并通过实际工程案例对该方法进行验证。%Purging in silo can efficiently avoid the occurrence possibility of explosion in polypropylene silo. In this paper, the flow process of purging in polypropylene silo was introduced. The calculation of pressure drop in purging process under the condition of pellet bed was emphatically described, and with practical example this method was verified.

  20. Preparation and application of purging upper nozzle for continuous casting tundish%连铸中间包透气上水口的研制与应用

    Institute of Scientific and Technical Information of China (English)

    徐志伟; 陈荣

    2000-01-01

    Property and variety of purging upper nozzle and the requirement of continuous casting process for thenozzle were introduced. Using synthetic mullite,α-Al2 O3 and special binder prepared the dispersion mullitebased purging upper nozzle. The nozzle was used in large-sized steel plant such as Baosteel, etc, gain-ing good results.%介绍了连铸中间包透气上水口的性能和种类及连铸工艺对透气上水口性能的要求。利用合成莫来石颗粒、α-Al2O3细粉及特殊结合剂研制了弥散型莫来石质透气上水口,该水口在宝钢等大钢厂应用,取得了良好的使用效果。

  1. Optimization of Purge Bin Pressure in PE Unit%聚乙烯装置脱气仓压力的优化

    Institute of Scientific and Technical Information of China (English)

    刘卫东; 白鸿

    2013-01-01

      Purge bin pressure in PE unit was optimized by tuning the control loop and adjusting the filter bag. After optimization,pressure of purge bin was reduced, the degassing effect was improved,the hydrocarbon concentration of resin powder was reduced , which can make the PE plant run much more safely, and lay a foundation for the further reducing of nitrogen consumption.%  通过控制回路整定和滤袋调整优化了聚乙烯装置脱气仓的压力。优化后脱气压力降低,改善了脱气效果,降低了树脂粉末烃含量,使装置运行的安全性得到提高,为进一步降低氮气用量奠定基础。

  2. Volatile organic compounds in whole blood - determination by heated dynamic headspace purge and trap isotope-dilution GC/MS. Special report, November 1984-August 1987

    Energy Technology Data Exchange (ETDEWEB)

    Cramer, P.H.; Boggess, K.E.; Hosenfeld, J.M.

    1987-07-01

    The method described was developed for the determination of a selected list of 30 organic compounds in whole human blood. The method is a heated dynamic head-space purge and trap gas chromatographic method using mass spectrometry in the limited mass-scan mode. A whole blood sample is diluted with organic free water and the mixture fortified with isotopically labeled compounds. The mixture is subsequently heated to 50/sup 0/C while stirred, and the volatile components are purged from the mixture and collected on an adsorbent trap. The volatile compounds are thermally desorbed from the trap onto a wide-bore fused-silica capillary column. Detection of the compounds is accomplished using mass spectrometry in the limited mass-scan mode where only selected ions are scanned. Quantitation of the analytes is accomplished by using the specific ion responses from standards of the analytes and their corresponding labeled analogs or internal standards.

  3. Progress and developing trend of purging plug for refining ladle%精炼钢包用透气砖的研究进展与发展方向

    Institute of Scientific and Technical Information of China (English)

    贾全利; 吴然; 孙小改

    2013-01-01

    总结了精炼钢包用透气砖的损毁原因和现用刚玉-尖晶石透气砖在改善抗热震性方面的研究新进展;介绍了非氧化物结合刚玉质透气砖的研究结果和在精炼钢包上的使用情况,提出了透气砖的研究和发展方向.%Damage reasons of purging plug for refining ladle and research progress on thermal shock resistance of corundum-spinel purging plug were summarized. Research achievements and application results of nonoxides bonded corundum purging plug for refining ladle were reviewed. The further research and developing trend of purging plug were proposed.

  4. Determining the Henry's Law constants of THMs in seawater by means of purge-and-trap gas chromatography (PT-GC): the influence of seawater as sample matrix.

    Science.gov (United States)

    Ruiz-Bevia, Francisco; Fernandez-Torres, Maria J

    2010-01-01

    The influence of seawater salts as salting out agents on the purge-and-trap gas chromatography (PT-GC) determination of trihalomethanes (THMs) was studied. This is particularly important since seawater is chlorinated when used as a cooling agent in coastal nuclear power stations. The chlorination produces unwanted THMs as by-products. A PT-GC apparatus was used to determine the Henry's Law constant of each THM, with seawater as the sample matrix.

  5. 吹扫型火焰控制器管路模型的设计%Design of Pipeline Model of Purge Type Flame Controller

    Institute of Scientific and Technical Information of China (English)

    朱利军

    2011-01-01

    The function, connection diagram and correlation element of purge type flame controller are introduced. The pipeline model is designed and connection diagram is given.%介绍吹扫型火焰控制器的功能、接线原理图及相关器件,设计相应的管路模型,并给出接线图。

  6. Preliminary Examination of Glucagon-Like Peptide-1 Levels in Women with Purging Disorder and Bulimia Nervosa

    Science.gov (United States)

    Dossat, Amanda M.; Bodell, Lindsay P.; Williams, Diana L.; Eckel, Lisa A.; Keel, Pamela K.

    2014-01-01

    Objective This study examined pre- and post-prandial glucagon-like peptide 1 (GLP-1) levels in women with bulimia nervosa (BN), purging disorder (PD), and non-eating disorder control women to better understand whether alterations in satiation-related hormones in BN may be linked to binge-eating episodes or other altered ingestive behaviors. Method Participants included women with BN (n = 19), PD (n = 14), or controls (n = 14). Participants provided subjective ratings for hunger and fullness and plasma samples before and after consumption of a standardized test meal. Results As expected, GLP-1 levels increased significantly following test meal consumption; however, participants with BN displayed significantly lower GLP-1 levels compared to PD and control participants both before and after consumption of the test meal. There were no significant differences between PD and control participants in GLP-1 levels, but individuals with PD displayed significantly higher levels of fullness throughout the test meal as compared to both control and BN participants. Discussion Our findings provide preliminary evidence that reduced GLP-1 levels in individuals with BN may be associated with binge-eating episodes. Additionally, increased fullness in individuals with PD does not appear to be accounted for by exaggerated post-prandial GLP-1 release. PMID:24590464

  7. Comparison of purge and trap GC/MS and purgeable organic chloride analysis for monitoring volatile chlorinated hydrocarbons

    Science.gov (United States)

    Barber, Larry B.; Thurman, E. Michael; Takahashi, Yoshi; Noriega, Mary C.

    1992-01-01

    A combined field and laboratory study was conducted to compare purge and trap gas chromatography/mass spectrometry (PT-GC/MS) and purgeable organic chloride (POCl) analysis for measuring volatile chlorinated hydrocarbons (VCH) in ground water. Distilled-water spike and recovery experiments using 10 VCH indicate that at concentrations greater than 1 ??g/l recovery is more than 80 percent for both methods with relative standard deviations of about 10 percent. Ground-water samples were collected from a site on Cape Cod, Massachusetts, where a shallow unconfined aquifer has been contaminated by VCH, and were analyzed by both methods. Results for PT-GC/MS and POCl analysis of the ground-water samples were not significantly different (alpha = 0.05, paired t-test analysis) and indicated little bias between the two methods. Similar conclusions about concentrations and distributions of VCH in the ground-water contamination plume were drawn from the two data sets. However, only PT-GC/MS analysis identified the individual compounds present and determined their concentrations, which was necessary for toxicological and biogeochemical evaluation of the contaminated ground water. POCl analysis was a complimentary method for use with PT-GC/MS analysis for identifying samples with VCH concentrations below the detection limit or with high VCH concentrations that require dilution. Use of POCl as a complimentary monitoring method for PT-GC/MS can result in more efficient use of analytical resources.

  8. Gas purge microsyringe extraction for quantitative direct gas chromatographic-mass spectrometric analysis of volatile and semivolatile chemicals.

    Science.gov (United States)

    Yang, Cui; Piao, Xiangfan; Qiu, Jinxue; Wang, Xiaoping; Ren, Chunyan; Li, Donghao

    2011-03-25

    Sample pretreatment before chromatographic analysis is the most time consuming and error prone part of analytical procedures, yet it is a key factor in the final success of the analysis. A quantitative and fast liquid phase microextraction technique termed as gas purge microsyringe extraction (GP-MSE) has been developed for simultaneous direct gas chromatography-mass spectrometry (GC-MS) analysis of volatile and semivolatile chemicals without cleanup process. Use of a gas flowing system, temperature control and a conventional microsyringe greatly increased the surface area of the liquid phase micro solvent, and led to quantitative recoveries of both volatile and semivolatile chemicals within short extraction time of only 2 min. Recoveries of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and alkylphenols (APs) determined were 85-107%, and reproducibility was between 2.8% and 8.5%. In particular, the technique shows high sensitivity for semivolatile chemicals which is difficult to achieve in other sample pretreatment techniques such as headspace-liquid phase microextraction. The variables affecting extraction efficiency such as gas flow rate, extraction time, extracting solvent type, temperature of sample and extracting solvent were investigated. Finally, the technique was evaluated to determine PAHs, APs and OCPs from plant and soil samples. The experimental results demonstrated that the technique is economic, sensitive to both volatile and semivolatile chemicals, is fast, simple to operate, and allows quantitative extraction. On-site monitoring of volatile and semivolatile chemicals is now possible using this technique due to the simplification and speed of sample treatment.

  9. In-tube extraction of volatile organic compounds from aqueous samples: an economical alternative to purge and trap enrichment.

    Science.gov (United States)

    Laaks, Jens; Jochmann, Maik A; Schilling, Beat; Schmidt, Torsten C

    2010-09-15

    A novel in-tube extraction device (ITEX 2) for headspace sampling was evaluated for GC/MS analysis of aqueous samples. Twenty compounds of regulatory and drinking water quality importance were analyzed, including halogenated hydrocarbons, BTEX compounds (benzene, toluene, ethylbenzene, xylenes), fuel oxygenates, geosmin, and 2-methylisoborneol. Five commercially available sorbent traps were compared for their compound specific extraction yield. On the basis of the results, a mixed bed trap was prepared and evaluated. The extraction parameters were optimized to yield maximum sensitivity within the time of a GC run, to avoid unnecessary downtime of the system. Method detection limits of 1-10 ng L(-1) were achieved for volatile organic compounds (VOCs), which is much lower than demands by regulatory limit values. The performance of the ITEX system is similar to that of purge and trap systems, but it requires lower sample volumes and is less prone to contamination, much simpler, more flexible, and affordable. Average relative standard deviations below 10% were achieved for all analytes, and recoveries from spiked tap water samples were between 90% and 103%, mostly. The extraction is nonexhaustive, removing a fraction of 7% to 55% of the target compounds, depending on the air-water partitioning coefficients. The method was also tested with nonsynthetic samples, including tap, pond, and reservoir water and different soft drinks.

  10. Gas purge-microsyringe extraction: a rapid and exhaustive direct microextraction technique of polycyclic aromatic hydrocarbons from plants.

    Science.gov (United States)

    Wang, Juan; Yang, Cui; Li, Huijie; Piao, Xiangfan; Li, Donghao

    2013-12-17

    Gas purge-microsyringe extraction (GP-MSE) is a rapid and exhaustive microextraction technique for volatile and semivolatile compounds. In this study, a theoretical system of GP-MSE was established by directly extracting and analyzing 16 kinds of polycyclic aromatic hydrocarbons (PAHs) from plant samples. On the basis of theoretical consideration, a full factorial experimental design was first used to evaluate the main effects and interactions of the experimental parameters affecting the extraction efficiency. Further experiments were carried out to determine the extraction kinetics and desorption temperature-dependent. The results indicated that three factors, namely desorption temperature (temperature of sample phase) Td, extraction time t, and gas flow rate u, had a significantly positive effect on the extraction efficiency of GP-MSE for PAHs. Extraction processes of PAHs in plant samples followed by first-order kinetics (relative coefficient R(2) of simulation curves were 0.731-1.000, with an average of 0.958 and 4.06% relative standard deviation), and obviously depended on the desorption temperature. Furthermore, the effect of the matrix was determined from the difference in Eapp,d. Finally, satisfactory recoveries of 16 PAHs were obtained using optimal parameters. The study demonstrated that GP-MSE could provide a rapid and exhaustive means of direct extraction of PAHs from plant samples. The extraction kinetics were similar that of the inverse process of the desorption kinetics of the sample phase.

  11. Empirically defining rapid response to intensive treatment to maximize prognostic utility for bulimia nervosa and purging disorder.

    Science.gov (United States)

    MacDonald, Danielle E; Trottier, Kathryn; McFarlane, Traci; Olmsted, Marion P

    2015-05-01

    Rapid response (RR) to eating disorder treatment has been reliably identified as a predictor of post-treatment and sustained remission, but its definition has varied widely. Although signal detection methods have been used to empirically define RR thresholds in outpatient settings, RR to intensive treatment has not been investigated. This study investigated the optimal definition of RR to day hospital treatment for bulimia nervosa and purging disorder. Participants were 158 patients who completed ≥6 weeks of day hospital treatment. Receiver operating characteristic (ROC) analysis was used to create four definitions of RR that could differentiate between remission and nonremission at the end of treatment. Definitions were based on binge/vomit episode frequency or percent reduction from pre-treatment, during either the first four or first two weeks of treatment. All definitions were associated with higher remission rates in rapid compared to nonrapid responders. Only one definition (i.e., ≤3 episodes in the first four weeks of treatment) predicted sustained remission (versus relapse) at 6- and 12-month follow-up. These findings provide an empirically derived definition of RR to intensive eating disorder treatment, and provide further evidence that early change is an important prognostic indicator. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. The loss of essential oil components induced by the Purge Time in the Pressurized Liquid Extraction (PLE) procedure of Cupressus sempervirens.

    Science.gov (United States)

    Dawidowicz, Andrzej L; Czapczyńska, Natalia B; Wianowska, Dorota

    2012-05-30

    The influence of different Purge Times on the effectiveness of Pressurized Liquid Extraction (PLE) of volatile oil components from cypress plant matrix (Cupressus sempervirens) was investigated, applying solvents of diverse extraction efficiencies. The obtained results show the decrease of the mass yields of essential oil components as a result of increased Purge Time. The loss of extracted components depends on the extrahent type - the greatest mass yield loss occurred in the case of non-polar solvents, whereas the smallest was found in polar extracts. Comparisons of the PLE method with Sea Sand Disruption Method (SSDM), Matrix Solid-Phase Dispersion Method (MSPD) and Steam Distillation (SD) were performed to assess the method's accuracy. Independent of the solvent and Purge Time applied in the PLE process, the total mass yield was lower than the one obtained for simple, short and relatively cheap low-temperature matrix disruption procedures - MSPD and SSDM. Thus, in the case of volatile oils analysis, the application of these methods is advisable.

  13. Report on the analysis of common beverages spiked with gamma-hydroxybutyric acid (GHB) and gamma-butyrolactone (GBL) using NMR and the PURGE solvent-suppression technique.

    Science.gov (United States)

    Lesar, Casey T; Decatur, John; Lukasiewicz, Elaan; Champeil, Elise

    2011-10-10

    In forensic evidence, the identification and quantitation of gamma-hydroxybutyric acid (GHB) in "spiked" beverages is challenging. In this report, we present the analysis of common alcoholic beverages found in clubs and bars spiked with gamma-hydroxybutyric acid (GHB) and gamma-butyrolactone (GBL). Our analysis of the spiked beverages consisted of using (1)H NMR with a water suppression method called Presaturation Utilizing Relaxation Gradients and Echoes (PURGE). The following beverages were analyzed: water, 10% ethanol in water, vodka-cranberry juice, rum and coke, gin and tonic, whisky and diet coke, white wine, red wine, and beer. The PURGE method allowed for the direct identification and quantitation of both compounds in all beverages except red and white wine where small interferences prevented accurate quantitation. The NMR method presented in this paper utilizes PURGE water suppression. Thanks to the use of a capillary internal standard, the method is fast, non-destructive, sensitive and requires no sample preparation which could disrupt the equilibrium between GHB and GBL.

  14. Epistatic interactions involving DRD2, DRD4, and COMT polymorphisms and risk of substance abuse in women with binge-purge eating disturbances.

    Science.gov (United States)

    Steiger, Howard; Thaler, Lea; Gauvin, Lise; Joober, Ridha; Labbe, Aurelie; Israel, Mimi; Kucer, Audrey

    2016-06-01

    Substance abuse is common in individuals with bulimia-spectrum (binge-purge) eating disturbances, a co-occurrence that has been attributed to shared neurobiological substrates--notably alterations in dopaminergic activity. We examined the implications of variations of selected, dopamine-relevant polymorphisms (DRD2 Taq1A, DRD4 7R, and COMT) for risk of substance abuse in women with binge-purge eating syndromes. We genotyped 183 women (66.1% showing full-threshold BN and 33.9% showing sub-syndromic variants), and assessed lifetime presence of alcohol, cannabis, cocaine, and stimulant abuse or dependence using structured interviews. Tests for main and interaction effects of various allele combinations revealed that individuals who carried high function COMT and low-function DRD4 7R alleles (a combination expected to be associated with higher risk) did indeed show more lifetime substance abuse and, specifically, more cannabis abuse. Our findings suggest that a gene combination that, in theory, codes for low levels of dopaminergic neurotransmission coincides with sensitivity to substance abuse in a sample displaying binge-purge eating-disorder variants.

  15. 吹扫捕集-气质联用测定水中苯系物%Purge and trap- determination of BTEXs in water by GC/MS

    Institute of Scientific and Technical Information of China (English)

    韩增玉; 黄彬

    2012-01-01

    The BTEXs were enriched by the system of purge - trap, then determined by GC/MS. The effects that include the conditions of GC, the time of purge, flow rate of purge and the time of desorption , the temp of de- sorption were discussed. The average recoveries were 96 - 102%. The limits of detection were 0.03 -0.39μg/L. The method can be applied to analysis of BTEXs in water.%以吹扫捕集方式,通过GC/MS测定水中苯系物。考察了吹扫时间、吹扫流量、解析时间、解析温度对回收率的影响,确定了测定水中苯系物最佳实验条件。方法平均回收率96%~102%,检出限为0.03~0.39μg/L,本方法可用于水中痕量苯系物测定。

  16. Purge-assisted headspace solid-phase microextraction combined with gas chromatography-mass spectrometry for determination of chlorophenols in aqueous samples.

    Science.gov (United States)

    Ho, Hsin-Pin; Lee, Ren-Jye; Lee, Maw-Rong

    2008-12-12

    A simple, economical and very effective method is demonstrated for simultaneous determination of 2,4-dichlorophenol, 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol and pentachlorophenol, in aqueous samples, by using purge-assisted headspace solid-phase microextraction (PA/HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). In the new method, purging the sample enhances the removal of the trace chlorophenols without derivatization from the matrices to the headspace. Extraction parameters including extraction temperature, purge gas flow rate and extraction time were systematically investigated. Under optimal conditions, the relative standard deviations (RSDs) were 4-11% at 50 pg/mL and 5-14% at 5 pg/mL, respectively. The recoveries were in the range of 83-114%. Detection limits were determined at the fg level. These results indicate that PA/HS-SPME provides a significant contribution to highly efficient extraction of semi-volatile CPs, especially for pentachlorophenol, which has the smallest Henry's constant and large octanol-water partitioning coefficient. In addition, the proposed method was successfully applied to the analysis of chlorophenols in landfill leachate. New perspectives are opened for headspace extraction of relatively low vapor pressure compounds in complex matrices.

  17. Purge gas recovery of ammonia synthesis plant by integrated configuration of catalytic hydrogen-permselective membrane reactor and solid oxide fuel cell as a novel technology

    Science.gov (United States)

    Siavashi, Fakhteh; Saidi, Majid; Rahimpour, Mohammad Reza

    2014-12-01

    The purge gas emission of ammonia synthesis plant which contains hazardous components is one of the major sources of environmental pollution. Using integrated configuration of catalytic hydrogen-permselective membrane reactor and solid oxide fuel cell (SOFC) system is a new approach which has a great impact to reduce the pollutant emission. By application of this method, not only emission of ammonia and methane in the atmosphere is prevented, hydrogen is produced through the methane steam reforming and ammonia decomposition reactions that take place simultaneously in a catalytic membrane reactor. The pure generated hydrogen by recovery of the purge gas in the Pd-Ag membrane reactor is used as a feed of SOFC. Since water is the only byproduct of the electrochemical reaction in the SOFC, it is recycled to the reactor for providing the required water of the reforming reaction. Performance investigation of the reactor represents that the rate of hydrogen permeation increases with enhancing the reactor temperature and pressure. Also modeling results indicate that the SOFC performance improves with increasing the temperature and fuel utilization ratio. The generated power by recovery of the purging gas stream of ammonia synthesis plant in the Razi petrochemical complex is about 8 MW.

  18. Predicting the consequences of selecting on PrP genotypes on PrP frequencies, performance and inbreeding in commercial meat sheep populations

    Directory of Open Access Journals (Sweden)

    Boulton Kay

    2007-11-01

    Full Text Available Abstract Selection programmes based on prion protein (PrP genotypes are being implemented for increasing resistance to scrapie. Commercial meat sheep populations participating in sire-referencing schemes were simulated to investigate the effect of selection on PrP genotypes on ARR and VRQ allele frequencies, inbreeding and genetic gain in a performance trait under selection. PrP selection strategies modelled included selection against the VRQ allele and in favour of the ARR allele. Assuming realistic initial PrP frequencies, selection against the VRQ allele had a minimal impact on performance and inbreeding. However, when selection was also in favour of the ARR allele and the frequency of this allele was relatively low, there was a loss of up to three to four years of genetic gain over the 15 years of selection. Most loss in gain occurred during the first five years. In general, the rate of inbreeding was reduced when applying PrP selection. Since animals were first selected on their PrP genotype before being selected on the performance trait, the intensity of selection on performance was weaker under PrP selection (compared with no PrP selection. Eradication of the VRQ allele or fixation of the ARR allele within 15 years of selection was possible only with PrP selection targeting all breeding animals.

  19. [Causes of depression].

    Science.gov (United States)

    Fernández, Francisco Alonso

    2011-01-01

    This paper describes four nosological categories of depressive disorder according to the fundamental or prime cause: endogen depression, situative depression, psychogen depression and somatogen (also pharmacogen or addictive) depression. Recent advances in neurobiology provide the commun pathogenic mechanism distribuited in neurochemical, neuroendocrine and neuroinmune factors, with at the end a cellular and molecular sequence beyond the synapse. There is an increased risk of depression multiplied by three or four in the elderly, obese, unemployed and inmigrant and it is very frequent in terminally ill patients with a pervasive desire for death. Finally, eight personalized preventive guidelines enable to decrease the individual risk of depression in more than a fifty per cent.

  20. Therapieresistente Depression

    Directory of Open Access Journals (Sweden)

    Holsboer-Trachsler E

    2006-01-01

    Full Text Available In der Behandlung einer Depression wird ein Nichtansprechen auf zwei adäquate Antidepressivatherapien während je 6–8 Wochen als Therapieresistenz bezeichnet. Da häufig zu geringe Dosierungen oder eine zu kurze Behandlungsdauer die Ursache für ein Nichtansprechen sind, sollte in einem ersten Schritt die medikamentöse Therapie hinsichtlich Dauer und Dosierung, eventuell unter Einbezug von Plasmaspiegelbestimmungen, überprüft und optimiert werden. Als pharmakologische Maßnahmen werden zunächst ein Wechsel des Antidepressivums und danach eine Kombination von verschiedenen Antidepressiva mit unterschiedlichem biochemischem Wirkungsansatz empfohlen. Zeigen beide nicht den gewünschten Erfolg, so sollte zusätzlich zur bestehenden Antidepressivabehandlung eine Augmentationstherapie, primär mit Lithium und/oder dem Schilddrüsenhormon T3, durchgeführt werden. Ein neuer, vielversprechender Behandlungsansatz ist eine Augmentationstherapie mit atypischen Neuroleptika. Als akut wirkende nichtpharmakologische Zusatzmaßnahme hat sich der partielle Schlafentzug bewährt. Weitere nichtpharmakologische Strategien umfassen Psychotherapie, Elektrokrampftherapie und Vagusnervstimulationsbehandlung.

  1. Pedigree-based inbreeding coefficient explains more variation in fitness than heterozygosity at 160 microsatellites in a wild bird population.

    Science.gov (United States)

    Nietlisbach, Pirmin; Keller, Lukas F; Camenisch, Glauco; Guillaume, Frédéric; Arcese, Peter; Reid, Jane M; Postma, Erik

    2017-03-15

    Although the pedigree-based inbreeding coefficient F predicts the expected proportion of an individual's genome that is identical-by-descent (IBD), heterozygosity at genetic markers captures Mendelian sampling variation and thereby provides an estimate of realized IBD. Realized IBD should hence explain more variation in fitness than their pedigree-based expectations, but how many markers are required to achieve this in practice remains poorly understood. We use extensive pedigree and life-history data from an island population of song sparrows (Melospiza melodia) to show that the number of genetic markers and pedigree depth affected the explanatory power of heterozygosity and F, respectively, but that heterozygosity measured at 160 microsatellites did not explain more variation in fitness than F This is in contrast with other studies that found heterozygosity based on far fewer markers to explain more variation in fitness than F Thus, the relative performance of marker- and pedigree-based estimates of IBD depends on the quality of the pedigree, the number, variability and location of the markers employed, and the species-specific recombination landscape, and expectations based on detailed and deep pedigrees remain valuable until we can routinely afford genotyping hundreds of phenotyped wild individuals of genetic non-model species for thousands of genetic markers. © 2017 The Author(s).

  2. Dialectical behavior therapy for adolescent binge eating, purging, suicidal behavior, and non-suicidal self-injury: a pilot study.

    Science.gov (United States)

    Fischer, Sarah; Peterson, Claire

    2015-03-01

    There are few published randomized controlled trials examining treatment for symptoms of bulimia nervosa (BN) in adolescents. Additionally, many adolescents presenting for treatment for BN symptoms endorse co-occurring mood disturbances, suicidality, and nonsuicidal self-injury (NSSI), and may not meet full Diagnostic and Statistical Manual-IV-Text Revision (DSM-IV-TR) diagnostic criteria for BN. In addition to the limited number of randomized controlled trials, published treatment studies of BN symptoms in adolescence do not specifically address the multiple comorbid symptoms that these adolescents often report. The purpose of this pilot study was to examine the feasibility and effectiveness of an outpatient dialectical behavior therapy (DBT) program for adolescents with symptoms of BN, suicide attempts, and NSSI. Ten eligible participants enrolled in the study; 3 dropped within 4 weeks of initiating treatment. In addition to binge eating and suicidal behavior, participants also endorsed a number of other comorbid mood disorders and substance abuse. Seven participants completed 6 months of treatment and 6-month follow-up assessments. Treatment included access to a crisis management system, individual therapy, skills training, and a therapist consultation team. At posttreatment, participants had significantly reduced self-harm; (Cohen's d = 1.35), frequency of objective binge episodes (Cohen's d = .46), frequency of purging (Cohen's d = .66), and Global Eating Disorder Examination scores (Cohen's d = .64). At follow-up, 6 participants were abstinent of NSSI; 3 participants were abstinent from binge eating. At follow-up, treatment gains were maintained and enhanced. Results indicate that it is feasible to address multiple forms of psychopathology during the treatment of BN symptoms in this age-group.

  3. Distribution characteristics of volatile methylsiloxanes in Tokyo Bay watershed in Japan: Analysis of surface waters by purge and trap method.

    Science.gov (United States)

    Horii, Yuichi; Minomo, Kotaro; Ohtsuka, Nobutoshi; Motegi, Mamoru; Nojiri, Kiyoshi; Kannan, Kurunthachalam

    2017-05-15

    Surface waters including river water and effluent from sewage treatment plants (STPs) were collected from Tokyo Bay watershed, Japan, and analyzed for seven cyclic and linear volatile methylsiloxanes (VMSs), i.e., D3, D4, D5, D6, L3, L4, and L5 by an optimized purge and trap extraction method. The total concentrations of seven VMSs (ΣVMS) in river water ranged from <4.9 to 1700ng/L (mean: 220ng/L). The individual mean concentrations of cyclic VMSs in surface waters were; 10ng/L for D3, 13ng/L for D4, 180ng/L for D5, and 18ng/L for D6. The concentrations of ΣVMS determined in STP effluents varied widely from 99 to 2500ng/L and the individual mean concentrations were 21ng/L for D3, 27ng/L for D4, 540ng/L for D5, and 45ng/L for D6. D5, which is widely used in personal-care products, was found to be the most abundant compound in both river water and STP effluent. Linear VMSs were detected at much lower frequency and concentrations than those of cyclic VMSs. The measured concentrations of D4 were below the no-observed effect concentration (NOEC). The annual emission of ΣVMS through STPs into Tokyo Bay watershed was estimated at 2300kg. Our results indicate widespread distribution of VMSs in Tokyo Bay watershed and the influence of domestic wastewater discharges as a source of VMSs in the aquatic environment.

  4. Anxiety and compulsion patterns in the maintenance of bingeing/purging behaviours by individuals with bulimia nervosa.

    Science.gov (United States)

    Thomas, M; Lovell, A

    2015-02-01

    Bulimia nervosa, if not treated or if treated unsuccessfully, can develop into a severe and enduring eating disorder. Analysis of self-management of Seed-BN indicates that individuals frequently experience significant negative mental health issues and a complex relationship with medication management. Two discrete patterns of coping strategies to prevent deterioration in distressing symptoms were in evidence, controlled vomiting, which was related to the management of anxiety, and uncontrolled vomiting due to more dominant self-management of compulsive acts. The implications for nursing revolve around accurate assessment of vomiting and subsequent engagement by the individual with their coping strategies in relation to perceived deterioration in distressing symptoms. This paper reports on the results of a study into the self-reported coping strategies employed by a small sample (n = 12) of individuals diagnosed with bulimia nervosa purging sub-type, severe and enduring eating disorder (Seed-BN), referred to an outpatient clinic for psychotherapy. Data collection focused on the vomiting activities of participants through analysis of their self-management from diary extracts, which recorded vomiting patterns. Participants all experienced significant mental health issues, had complex histories of BN over a prolonged period, difficulties maintaining relationships, and many had an additional history of substance misuse including dependence on prescription drugs. The study findings indicated two different self-management strategies, anxiety containment and compulsion maintenance. There was a clear association between anxiety and controlled weekly vomiting patterns compared with compulsion and daily vomiting patterns. The implications for nursing practice relate to the potential for assessment of differences in vomiting patterns to indicate self-management status and subsequent interventions focusing on either anxiety or compulsive patterns. © 2014 John Wiley & Sons Ltd.

  5. [Depression in schizophrenia].

    Science.gov (United States)

    Rigaud, A S

    1991-03-01

    Depressive symptoms are frequent during schizophrenia. Depression occurs in the course of a schizo affective psychose or in the course of a schizophrenia (either with acute psychotic symptoms, either without acute psychotic symptoms). Differentiating depression from negative symptoms of schizophrenia or from antipsychotic drug induced side effects can be difficult. The question to know whether depression is intrinsic to the disease process itself whether it is secondary to the schizophrenic process is still a matter of inquiry. Efficacy of antidepressive drugs during depression in schizophrenia remains a matter of controversy. Depression increases the risk for pejorative evolution and for suicide in schizophrenia.

  6. THE SIGNIFICANCE OF GENETIC EROSION IN THE PROCESS OF EXTINCTION .4. INBREEDING DEPRESSION AND HETEROSIS EFFECTS CAUSED BY SELFING AND OUTCROSSING IN SCABIOSA-COLUMBARIA

    NARCIS (Netherlands)

    VANTREUREN, R; BIJLSMA, R; OUBORG, NJ; VANDELDEN, W

    1993-01-01

    The effects of self-fertilization, within-population crosses (WPC) and between-population crosses (BPC) on progeny fitness were investigated in the greenhouse for Scabiosa columbaria populations of varying size. Plants grown from field collected seeds were hand pollinated to produce selfed, WPC, and

  7. Memory training in depression

    NARCIS (Netherlands)

    Becker, E.S.; Vanderhasselt, M.A.; Vrijsen, J.N.

    2015-01-01

    Memory biases, that is, general memory impairments as well as specific mood-congruent memory biases, are important vulnerability factors in depression. Recently, computerized memory trainings have been developed to target these biases, reducing rumination and lightening depressive symptoms. This

  8. Depression and Suicide Risk

    Science.gov (United States)

    Depression and Suicide Risk (2014) Definition: A mood disorder that causes a persistent feeling of sadness and ... i Prevalence: 1. Ranges of lifetime risk for depression: from 6.7% overall to 40% in men, ...

  9. Depression and Pregnancy

    Science.gov (United States)

    ... best live chat Live Help Fact Sheets Share Depression Thursday, 01 September 2016 In every pregnancy, a ... risk. This sheet talks about whether exposure to depression may increase the risk for birth defects over ...

  10. Heart disease and depression

    Science.gov (United States)

    ... gov/ency/patientinstructions/000790.htm Heart disease and depression To use the sharing features on this page, ... a heart attack or heart surgery Signs of Depression It is pretty common to feel down or ...

  11. Learning about depression

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000325.htm Learning about depression To use the sharing features on this page, ... trigger or reason. What are the Signs of Depression? You may notice some or all of the ...

  12. Depression - stopping your medicines

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000570.htm Depression - stopping your medicines To use the sharing features ... prescription medicines you may take to help with depression, anxiety, or pain. Like any medicine, there are ...

  13. Depression and Pregnancy

    Science.gov (United States)

    ... best live chat Live Help Fact Sheets Share Depression Thursday, 01 September 2016 In every pregnancy, a ... risk. This sheet talks about whether exposure to depression may increase the risk for birth defects over ...

  14. Depression Disturbs Germany

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The suicide of Robert Enke,the goalkeeper of the Germany national football team who had battled depression for years,stunned the country and cast depression into the national spotlight as a disturbing disease.

  15. Conductas purgativas y estado nutricional en anorexia nerviosa y bulimia nerviosa Purging behaviours and nutritional status in anorexia nervosa and bulimia nervosa

    Directory of Open Access Journals (Sweden)

    F. J. Vaz

    2003-10-01

    patients (63.0% fulfilled the DSMIV diagnostic criteria for BN (90 purging type, 26 nonpurging type. Sixty eight patients (37.0% fulfilled the DSM-IV criteria for the diagnosis of AN (48 restricting type, 20 binging-purging type. Methods: The asessment process included anthropometry (body circumferences and skinfold thickness and body impedance analysis. Results: The two subgroups of AN patients significantly differed from each of the BN subgroups. From a nutritional point of view, some significant differences between the two DSM-IV subtypes of AN existed, but not between the purging type and the nonpurging type of BN. Conclusions: The paper discusses the clinical significance of these findings. An alternative subtypification of AN patients is proposed: 1 restricting type [patients who control their food intake and do not purge]; 2 purging type [patient with true episodes of binging which are followed by purgative behaviors]; and 3 pseudopurging type [patients with subjective binging episodes who use purging methods].

  16. Preventing Depression in Adults With Subthreshold Depression

    DEFF Research Database (Denmark)

    Buntrock, Claudia; Berking, Matthias; Smit, Filip

    2017-01-01

    BACKGROUND: Psychological interventions for the prevention of depression might be a cost-effective way to reduce the burden associated with depressive disorders. OBJECTIVE: To evaluate the cost-effectiveness of a Web-based guided self-help intervention to prevent major depressive disorder (MDD......) in people with subthreshold depression (sD). METHODS: A pragmatic randomized controlled trial was conducted with follow-up at 12 months. Participants were recruited from the general population via a large statutory health insurance company and an open access website. Participants were randomized to a Web......-based guided self-help intervention (ie, cognitive-behavioral therapy and problem-solving therapy assisted by supervised graduate students or health care professionals) in addition to usual care or to usual care supplemented with Web-based psycho-education (enhanced usual care). Depression-free years (DFYs...

  17. Depression in cerebrovascular diseases

    OpenAIRE

    Voskresenskaya, Tatyana

    2009-01-01

    The paper discusses the topical problem of depression in cerebrovascular diseases. It shows its possible causes, mechanisms of occurrence, clinical picture and negative impact on the course of cerebrovascular disease and recovery of neurological functions. There is a bilateral association between stroke and depression: on the one hand, stroke is a risk factor for the development of depression and, on the other, depression is a both direct and indirect risk factor for the development of stroke...

  18. [Multiple mechanisms of depression].

    Science.gov (United States)

    Liu, Chun-Lin; Ruan, Ke-Feng; Gao, Jun-Wei; Wu, Fei; Zhang, Ji-Quan

    2013-08-01

    Depression is a grievous mental disease with an increasing high morbidity year by year and a serious social harm. The pathogenesises of depression is complicated and involves with multi-mechanisms and multi-organs. Recent studies demondtrate that in the nerval system and endocrine system there are many types of neurotransmitters and hormones, as well as their receptors, involved in depression. This paper reviews the research progress of depression in recent years.

  19. Method of treating depression

    Energy Technology Data Exchange (ETDEWEB)

    Henn, Fritz

    2013-04-09

    Methods for treatment of depression-related mood disorders in mammals, particularly humans are disclosed. The methods of the invention include administration of compounds capable of enhancing glutamate transporter activity in the brain of mammals suffering from depression. ATP-sensitive K.sup.+ channel openers and .beta.-lactam antibiotics are used to enhance glutamate transport and to treat depression-related mood disorders and depressive symptoms.

  20. Method of treating depression

    Science.gov (United States)

    Henn, Fritz [East Patchogue, NY

    2012-01-24

    Methods for treatment of depression-related mood disorders in mammals, particularly humans are disclosed. The methods of the invention include administration of compounds capable of enhancing glutamate transporter activity in the brain of mammals suffering from depression. ATP-sensitive K.sup.+ channel openers and .beta.-lactam antibiotics are used to enhance glutamate transport and to treat depression-related mood disorders and depressive symptoms.