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  1. Attachment to the Romantic Partner and Sibling: Attachment Hierarchies of Twins and Non-Twin Siblings

    Directory of Open Access Journals (Sweden)

    Sascha Schwarz

    2015-12-01

    Full Text Available Previous studies have shown that romantic partners and siblings are important attachment figures. This study compares the attachment to the romantic partner with the attachment to the sibling as a function of the participant’s sibling type among monozygotic (MZ twins, dizygotic (DZ twins, and non-twin (NT siblings. The results show that MZ twins prefer their sibling to their romantic partner whereas DZ twins are equally attached to their sibling and romantic partner. In contrast, NT siblings are more attached to their romantic partner compared to their sibling. These results indicate that genetic relatedness has profound impact on a person’s attachment hierarchy and the relative rank of the romantic partner and the sibling.

  2. Using Twins to Better Understand Sibling Relationships.

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    Mark, Katharine M; Pike, Alison; Latham, Rachel M; Oliver, Bonamy R

    2017-03-01

    We compared the nature of the sibling relationship in dyads of varying genetic relatedness, employing a behavioural genetic design to estimate the contribution that genes and the environment have on this familial bond. Two samples were used-the Sisters and Brothers Study consisted of 173 families with two target non-twin children (mean ages = 7.42 and 5.22 years respectively); and the Twins, Family and Behaviour study included 234 families with two target twin children (mean age = 4.70 years). Mothers and fathers reported on their children's relationship with each other, via a postal questionnaire (the Sisters and Brothers Study) or a telephone interview (the Twins, Family and Behaviour study). Contrary to expectations, no mean level differences emerged when monozygotic twin pairs, dizygotic twin pairs, and non-twin pairs were compared on their sibling relationship quality. Behavioural genetic analyses also revealed that the sibling bond was modestly to moderately influenced by the genetic propensities of the children within the dyad, and moderately to substantially influenced by the shared environment common to both siblings. In addition, for sibling negativity, we found evidence of twin-specific environmental influence-dizygotic twins showed more reciprocity than did non-twins. Our findings have repercussions for the broader application of results from future twin-based investigations.

  3. Solar twins and siblings in spectroscopic archives

    Science.gov (United States)

    Mahdi, D.; Soubiran, C.; Blanco-Cuaresma, S.

    2014-07-01

    Solar twins are stars that replicate the solar astrophysical properties. They represent natural candidates for harboring planetary systems similar to ours. Solar siblings are stars which were born in the same cluster than the Sun. They may differ from the Sun by their mass and radius, but they have the same age, the same chemical composition, and similar spatial velocities. Solar twins and siblings may have formed in the same conditions as the Sun, and thus they may give some clues on where and how the Sun formed in our Galaxy. In this study, we search the closest solar twins among thousands of solar type stars observed at high spectral resolution over the full optical range. The spectra are directly compared to solar ones observed by reflection on asteroids or the Moon with the same instrument. This purely differential method, based on the reduced χ2, is independant of any model. We applied it to a selection of ˜17700 spectra of ˜3500 different stars from the ELODIE archive. The star HD 146233 (18 Sco) keeps its status of the closest solar twin. The second closest star is the known solar twin HD 138573. Some other stars among the top twenty best stars have never been studied before, like HD 168009, HD 056124, and HD 029150. Atmospheric parameters of the top twenty solar twins were determined with the iSpec code. Their effective temperatures and gravities are found to be within 100 K and 0.1 dex from those of the Sun, respectively. We find the metallicity of the twins to be higher by 0.05 dex on average than that of the Sun. We derived the chemical abundances for the 200 closest solar twins in a line by line differential basis relative to the Sun. The absorption lines used in this study come from a rigorous analysis of 670 lines measured in our 14 solar spectra. We find several stars with all abundances within 0.01 dex from those of the Sun. Several of them fall on the Yonsei-Yale theoritical isochrone of solar age and metallicity. Thus they could have been

  4. Peer Network Overlap in Twin, Sibling, and Friend Dyads

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    McGuire, Shirley; Segal, Nancy L.

    2013-01-01

    Research suggests that sibling–peer connections are important for understanding adolescent problem behaviors. Using a novel behavioral genetic design, the current study investigated peer network overlap in 300 child–child pairs (aged 7-13 years) in 5 dyad types: monozygotic (MZ), dizygotic twins, full siblings (FSs), friend pairs, and virtual…

  5. The Maternal Emotional Climate Predicts Twin Sibling Relationship Quality.

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    Mark, Katharine M; Pike, Alison; Latham, Rachel M; Oliver, Bonamy R

    2017-04-01

    We investigated the association between maternal expressed emotion and twin relationship quality, after controlling for a maternal questionnaire measure of the mother-child relationship. This was explored within a community sample of 156 mothers and their two young twin children (M child age = 3.69 years; SD child age = 0.37). Mothers reported on the twin-twin relationship and the mother-child relationship via questionnaire. They were also interviewed about each child using the innovative Preschool Five Minute Speech Sample (Daley et al., 2003), which yields information about relative positive:negative maternal expressed emotion. Mothers who expressed more family-wide positive emotion and less family-wide negative emotion also reported more positivity, but not negativity, within the twin relationship - even when controlling for questionnaire reports of the mother-child relationship. Counter to expectations, discrepancies in mothers' expressed emotion between their twins also predicted more positive sibling relationships. Our findings corroborate the well established spill-over effect, whereby families are viewed as emotional units of interdependent individuals, none of whom can be understood in isolation from one another. Most importantly, the Preschool Five Minute Speech Sample provides information about mothering that questionnaire reports may not, and thus it is a useful tool in better understanding the twin family system.

  6. Variance Distribution in Sibling Relationships: Advantages of Multilevel Modeling Using Full Sibling Groups.

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    Marciniak, Karyn

    2017-03-01

    The majority of research on sibling relationships has investigated only one or two siblings in a family, but there are many theoretical and methodological limitations to this single dyadic perspective. This study uses multiple siblings (541 adults) in 184 families, where 96 of these families had all siblings complete the study, to demonstrate the value in including full sibling groups when conducting research on sibling relationships. Two scales, positivity and willingness to sacrifice, are evaluated with a multilevel model to account for the nested nature of family relationships. The distribution of variance across three levels: relationship, individual, and family are computed, and results indicate that the relationship level explains the most variance in positivity, whereas the individual level explains the majority of variance in willingness to sacrifice. These distributions are affected by gender composition and family size. The results of this study highlight an important and often overlooked element of family research: The meaning of a scale changes based on its distribution of variance at these three levels. Researchers are encouraged to be cognizant of the variance distribution of their scales when studying sibling relationships and to incorporate more full sibling groups into their research methods and study design. © 2015 Family Process Institute.

  7. Origins of Familial Similarity in Parenting: A Study of Twins and Adoptive Siblings.

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    Losoya, Sandra H.; Callor, Suzanne; Rowe, David C.; Goldsmith, H. Hill

    1997-01-01

    Parents who were identical twins, fraternal twins, or adopted siblings completed questionnaires assessing attitudes toward parenting and specific parenting practices, the emotional atmosphere of the home, and parental personality. Model-fitting results implicated modest genetic effects on affect-related aspects of parenting, such as parental…

  8. A Bivariate Genetic Analysis of Drug Abuse Ascertained Through Medical and Criminal Registries in Swedish Twins, Siblings and Half-Siblings.

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    Maes, Hermine H; Neale, Michael C; Ohlsson, Henrik; Zahery, Mahsa; Lichtenstein, Paul; Sundquist, Kristina; Sundquist, Jan; Kendler, Kenneth S

    2016-11-01

    Using Swedish nationwide registry data, the authors investigated the correlation of genetic and environmental risk factors in the etiology of drug abuse as ascertained from medical and criminal registries by modeling twin and sibling data. Medical drug abuse was defined using public inpatient and outpatient records, while criminal drug abuse was ascertained through legal records. Twin, full and half sibling pairs were obtained from the national twin and genealogical registers. Information about sibling pair residence within the same household was obtained from Statistics Sweden. Standard bivariate genetic structural equation modeling was applied to the population-based data on drug abuse ascertained through medical and crime registries, using OpenMx. Analyses of all possible pairs of twins (MZ: N = 4482; DZ: N = 9838 pairs), full- (N = 1,278,086) and half-siblings (paternal: N = 7767; maternal N = 70,553) who grew up together suggested that factors explaining familial resemblance for drug abuse as defined through medical or criminal registries were mostly the same. Results showed substantial heritability and moderate contributions of shared environmental factors to drug abuse; both were higher in males versus females, and higher for drug abuse ascertained through criminal than medical records. Because of the low prevalence of both assessments of drug abuse, having access to population data was crucial to obtain stable estimates. Using objective registry data, the authors found that drug abuse-whether ascertained through medical versus criminal records-was highly heritable. Furthermore, shared environmental factors contributed significantly to the liability of drug abuse. Genetic and shared environmental risk factors for these two forms of drug abuse were highly correlated.

  9. The association between unequal parental treatment and the sibling relationship in Finland: The difference between full and half-siblings.

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    Danielsbacka, Mirkka; Tanskanen, Antti O

    2015-06-24

    Studies have shown that unequal parental treatment is associated with relationship quality between siblings. However, it is unclear how it affects the relationship between full and half-siblings. Using data from the Generational Transmissions in Finland project (n = 1,537 younger adults), we study whether those who have half-siblings perceive more unequal parental treatment than those who have full siblings only. In addition, we study how unequal parental treatment is associated with sibling relationship between full, maternal, and paternal half-siblings. First, we found that individuals who have maternal and/or paternal half-siblings are more likely to have encountered unequal maternal treatment than individuals who have full siblings only. Second, we found that unequal parental treatment impairs full as well as maternal and paternal half-sibling relations in adulthood. Third, unequal parental treatment mediates the effect of genetic relatedness on sibling relations in the case of maternal half-siblings, but not in the case of paternal half-siblings. After controlling for unequal parental treatment, the quality of maternal half-sibling relationships did not differ from that of full siblings, whereas the quality of paternal half-sibling relationships still did. Fourth, the qualitative comments (n = 206) from the same population reveal that unequal parental treatment presents itself several ways, such as differential financial, emotional, or practical support.

  10. Multiple Regression Analysis of Reading Performance Data from Twin Pairs with Reading Difficulties and Non-twin Siblings: The Augmented Model

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    Wadsworth, S J; Olson, R. K.; Willcutt, E.G.; DeFries, J. C.

    2012-01-01

    The augmented multiple regression model for the analysis of data from selected twin pairs was extended to facilitate analyses of data from twin pairs and non-twin siblings. Fitting this extended model to data from both selected twin pairs and siblings yields direct estimates of heritability (h2) and the difference between environmental influences shared by members of twin pairs and those of sib or twin/sib pairs [i.e., c2(t) − c2(s)]. When this model was fitted to reading performance data fro...

  11. The Southern Illinois Twins and Siblings Study (SITSS): description and update.

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    Dilalla, Lisabeth Fisher; Gheyara, Sufna; Bersted, Kyle

    2013-02-01

    This update on the Southern Illinois Twins and Siblings Study (SITSS) documents some of the follow-up studies that have been conducted and results that have been obtained from this sample. At the current time, 283 twin pairs, 8 triplet families, 98 non-twin sibling pairs, and 287 singletons have been enrolled in SITSS. Twins and triplets are tested as young as 1 year of age and then every year on their birthday through age 5 years. A variety of follow-up studies have been conducted for SITSS children through age 20. Results thus far have demonstrated significant genetic influences on social behaviors such as aggression, victimization, and attention toward facial expressions. Interesting interactions have been documented between the dopamine receptor D4 gene (DRD4) and the social environment (parental sensitivity or peer aggression) as they predict children's aggressive behaviors. In addition, increased difficulty with social interactions has been noted for twins versus singletons. Thus, this multi-trait, multi-method behavior genetic data set contributes to our understanding of the etiology of social behaviors in preschoolers and to predictors of similar behaviors through adolescence.

  12. Individual Differences in Dynamic Measures of Verbal Learning Abilities in Young Twin Pairs and Their Older Siblings

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    van Soelen, Inge L. C.; van den Berg, Stephanie M.; Dekker, Peter H.; van Leeuwen, Marieke; Peper, Jiska S.; Hulshoff Pol, Hilleke E.; Boomsma, Dorret I.

    2009-01-01

    We explored the genetic background of individual differences in dynamic measures of verbal learning ability in children, using a Dutch version of the Auditory Verbal Learning Test (AVLT). Nine-year-old twin pairs (N = 112 pairs) were recruited from the Netherlands Twin Register. When possible, an older sibling between 10 and 14 years old…

  13. Individual Differences in Dynamic Measures of Verbal Learning Abilities in Young Twin Pairs and Their Older Siblings

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    van Soelen, Inge L. C.; van den Berg, Stephanie M.; Dekker, Peter H.; van Leeuwen, Marieke; Peper, Jiska S.; Hulshoff Pol, Hilleke E.; Boomsma, Dorret I.

    2009-01-01

    We explored the genetic background of individual differences in dynamic measures of verbal learning ability in children, using a Dutch version of the Auditory Verbal Learning Test (AVLT). Nine-year-old twin pairs (N = 112 pairs) were recruited from the Netherlands Twin Register. When possible, an older sibling between 10 and 14 years old…

  14. A twin-sibling study on the relationship between exercise attitudes and exercise behavior.

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    Huppertz, Charlotte; Bartels, Meike; Jansen, Iris E; Boomsma, Dorret I; Willemsen, Gonneke; de Moor, Marleen H M; de Geus, Eco J C

    2014-01-01

    Social cognitive models of health behavior propose that individual differences in leisure time exercise behavior are influenced by the attitudes towards exercise. At the same time, large scale twin-family studies show a significant influence of genetic factors on regular exercise behavior. This twin-sibling study aimed to unite these findings by demonstrating that exercise attitudes can be heritable themselves. Secondly, the genetic and environmental cross-trait correlations and the monozygotic (MZ) twin intrapair differences model were used to test whether the association between exercise attitudes and exercise behavior can be causal. Survey data were obtained from 5,095 twins and siblings (18-50 years). A genetic contribution was found for exercise behavior (50 % in males, 43 % in females) and for the six exercise attitude components derived from principal component analysis: perceived benefits (21, 27 %), lack of skills, support and/or resources (45, 48 %), time constraints (25, 30 %), lack of energy (34, 44 %), lack of enjoyment (47, 44 %), and embarrassment (42, 49 %). These components were predictive of leisure time exercise behavior (R(2) = 28 %). Bivariate modeling further showed that all the genetic (0.36 < |rA| < 0.80) and all but two unique environmental (0.00 < |rE| < 0.27) correlations between exercise attitudes and exercise behavior were significantly different from zero, which is a necessary condition for the existence of a causal effect driving the association. The correlations between the MZ twins' difference scores were in line with this finding. It is concluded that exercise attitudes and exercise behavior are heritable, that attitudes and behavior are partly correlated through pleiotropic genetic effects, but that the data are compatible with a causal association between exercise attitudes and behavior.

  15. Genetic and family and community environmental effects on drug abuse in adolescence: a Swedish national twin and sibling study.

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    Kendler, Kenneth S; Maes, Hermine H; Sundquist, Kristina; Ohlsson, Henrik; Sundquist, Jan

    2014-02-01

    Using Swedish nationwide registry data, the authors investigated genetic and environmental risk factors in the etiology of drug abuse by twin sibling modeling. The authors followed up with epidemiological analyses to identify shared environmental influences on drug abuse. Drug abuse was defined using public medical, legal, or pharmacy records. Twin and sibling pairs were obtained from the national twin and genealogical registers. Information about sibling pair residence within the same household, small residential area, or municipality was obtained from Statistics Sweden. The authors predicted concordance for drug abuse by years of co-residence until the older sibling turned 21 and risk for future drug abuse in adolescents living with parental figures as a function of family-level socioeconomic status and neighborhood social deprivation. The best twin sibling fit model predicted substantial heritability for drug abuse in males (55%) and females (73%), with environmental factors shared by siblings operating only in males and accounting for 23% of the variance in liability. For each year of living in the same household, the probability of sibling concordance for drug abuse increased 2%-5%. When not residing in the same household, concordance was predicted from residence in the same small residential area or municipality. Risk for drug abuse was predicted both by family socioeconomic status and neighborhood social deprivation. Controlling for family socioeconomic status, each year of living in a high social deprivation neighborhood increased the risk for drug abuse by 2%. Using objective registry data, the authors found that drug abuse is highly heritable. A substantial proportion of the shared environmental effect on drug abuse comes from community-wide rather than household-level influences. Genetic effects demonstrated in twin studies have led to molecular analyses to elucidate biological pathways. In a parallel manner, environmental effects can be followed up by

  16. Coordination difficulty and internalizing symptoms in adults: A twin/sibling study.

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    Waszczuk, Monika A; Leonard, Hayley C; Hill, Elisabeth L; Rowe, Richard; Gregory, Alice M

    2016-05-30

    Increased anxiety and depression symptoms have been reported in individuals with neurodevelopmental disorders, and have been found to be associated with motor coordination difficulties, but little is known about the etiology of these associations. This study aimed to assess genetic, shared (making twins/siblings alike) and non-shared (individual-specific) environmental influences on the association between poor coordination and symptoms of anxiety and depressed mood using a sample of adult twin and sibling pairs. Participants were asked about their coordination skill and anxiety and depression symptoms. About half of the variance in coordination difficulty was explained by familial (combined genetic and shared environmental) influences, with the remaining variance explained by non-shared environmental influences. Phenotypic associations between coordination and anxiety (r=.46) and depression symptoms (r=.44) were largely underpinned by shared familial liability for the three traits. Non-shared environment accounted for about a third of the phenotypic association. Results suggest that both familial and non-shared environmental influences play a role in the etiology of coordination difficulty and its association with internalizing symptoms. The current study highlights that both biological and environmental pathways shared between these symptoms should be examined in future research to inform prevention and treatment approaches in clinical settings.

  17. Genetic and Environmental Etiologies of Reading Difficulties: DeFries-Fulker Analysis of Reading Performance Data from Twin Pairs and Their Non-Twin Siblings

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    Astrom, Raven L.; Wadsworth, Sally J.; Olson, Richard K.; Willcutt, Erik G.; DeFries, John C.

    2012-01-01

    Reading performance data from 254 pairs of identical (MZ) and 420 pairs of fraternal (DZ) twins, 8.0 to 20.0 years of age, were subjected to multiple regression analyses. An extension of the DeFries-Fulker (DF) analysis (DeFries & Fulker, 1985, 1988) that facilitated inclusion of data from 303 of their nontwin siblings was employed. In addition to…

  18. Genetic and Environmental Etiologies of Reading Difficulties: DeFries-Fulker Analysis of Reading Performance Data from Twin Pairs and Their Non-Twin Siblings

    Science.gov (United States)

    Astrom, Raven L.; Wadsworth, Sally J.; Olson, Richard K.; Willcutt, Erik G.; DeFries, John C.

    2012-01-01

    Reading performance data from 254 pairs of identical (MZ) and 420 pairs of fraternal (DZ) twins, 8.0 to 20.0 years of age, were subjected to multiple regression analyses. An extension of the DeFries-Fulker (DF) analysis (DeFries & Fulker, 1985, 1988) that facilitated inclusion of data from 303 of their nontwin siblings was employed. In addition to…

  19. Similarity in General Mental Ability in Bedouin Full and Half Siblings.

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    Elbedour, Salman; Hur, Yoon-Mi; Bouchard, Thomas J., Jr.

    1997-01-01

    A battery of "g" loaded mental ability tests was administered to 274 Bedouin children and adolescents, full and half siblings from 106 families. Results demonstrate internal validity for the tests in this cultural context and support the idea that shared family environment is a strong determinant of sibling similarity for children in the given age…

  20. On the incidence of \\textit{WISE} infrared excess among solar analog, twin and sibling stars

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    Costa, Antônio D; Leão, Izan C; Lima, José E; da Silva, Danielly Freire; de Freitas, Daniel B; De Medeiros, José R

    2016-01-01

    This study presents a search for IR excess in the 3.4, 4.6, 12 and 22 $\\mu$m bands in a sample of 216 targets, composed of solar sibling, twin and analog stars observed by the \\textit{WISE} mission. In general, an infrared excess suggests the existence of warm dust around a star. We detected 12 $\\mu$m and/or 22 $\\mu$m excesses at the 3$\\sigma$ level of confidence in five solar analog stars, corresponding to a frequency of 4.1 $\\%$ of the entire sample of solar analogs analyzed, and in one out of 29 solar sibling candidates, confirming previous studies. The estimation of the dust properties shows that the sources with infrared excesses possess circumstellar material with temperatures that, within the uncertainties, are similar to that of the material found in the asteroid belt in our solar system. No photospheric flux excess was identified at the W1 (3.4 $\\mu$m) and W2 (4.6 $\\mu$m) \\textit{WISE} bands, indicating that, in the majority of stars of the present sample, no detectable dust is generated. Interesting...

  1. The genetic relationship between cannabis and tobacco cigarette use in European- and African-American female twins and siblings.

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    Agrawal, Arpana; Grant, Julia D; Lynskey, Michael T; Madden, Pamela A F; Heath, Andrew C; Bucholz, Kathleen K; Sartor, Carolyn E

    2016-06-01

    Use of cigarettes and cannabis frequently co-occurs. We examine the role of genetic and environmental influences on variation in and covariation between tobacco cigarette and cannabis use across European-American (EA) and African-American (AA) women. Data on lifetime cannabis and cigarette use were drawn from interviews of 956 AA and 3557 EA young adult female twins and non-twin same sex female full siblings. Twin modeling was used to decompose variance in and covariance between cigarette and cannabis use into additive genetic, shared, special twin and non-shared environmental sources. Cigarette use was more common in EAs (75.3%, 95% C.I. 73.8-76.7%) than AAs (64.2%, 95% C.I. 61.2-67.2%) while cannabis use was marginally more commonly reported by AAs (55.5%, 95% C.I. 52.5-58.8%) than EAs (52.4%, 95% C.I. 50.7-54.0%). Additive genetic factors were responsible for 43-66% of the variance in cigarette and cannabis use. Broad shared environmental factors (shared+special twin) played a more significant role in EA (23-29%) than AA (2-15%) women. In AA women, the influence of non-shared environment was more pronounced (42-45% vs. 11-19% in EA women). There was strong evidence for the same familial influences underlying use of both substances (rA=0.82-0.89; rC+T=0.70-0.75). Non-shared environmental factors were also correlated but less so (rE=0.48-0.66). No racial/ethnic differences were apparent in these sources of covariation. Heritability of cigarette and cannabis use is comparable across racial/ethnic groups. Differences in the contribution of shared and non-shared environmental influences indicate that different factors may shape substance use in EA and AA women. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Genetic influences on brain asymmetry: a DTI study of 374 twins and siblings.

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    Jahanshad, Neda; Lee, Agatha D; Barysheva, Marina; McMahon, Katie L; de Zubicaray, Greig I; Martin, Nicholas G; Wright, Margaret J; Toga, Arthur W; Thompson, Paul M

    2010-08-15

    Brain asymmetry, or the structural and functional specialization of each brain hemisphere, has fascinated neuroscientists for over a century. Even so, genetic and environmental factors that influence brain asymmetry are largely unknown. Diffusion tensor imaging (DTI) now allows asymmetry to be studied at a microscopic scale by examining differences in fiber characteristics across hemispheres rather than differences in structure shapes and volumes. Here we analyzed 4Tesla DTI scans from 374 healthy adults, including 60 monozygotic twin pairs, 45 same-sex dizygotic pairs, and 164 mixed-sex DZ twins and their siblings; mean age: 24.4years+/-1.9 SD). All DTI scans were nonlinearly aligned to a geometrically-symmetric, population-based image template. We computed voxel-wise maps of significant asymmetries (left/right differences) for common diffusion measures that reflect fiber integrity (fractional and geodesic anisotropy; FA, GA and mean diffusivity, MD). In quantitative genetic models computed from all same-sex twin pairs (N=210 subjects), genetic factors accounted for 33% of the variance in asymmetry for the inferior fronto-occipital fasciculus, 37% for the anterior thalamic radiation, and 20% for the forceps major and uncinate fasciculus (all L>R). Shared environmental factors accounted for around 15% of the variance in asymmetry for the cortico-spinal tract (R>L) and about 10% for the forceps minor (L>R). Sex differences in asymmetry (men>women) were significant, and were greatest in regions with prominent FA asymmetries. These maps identify heritable DTI-derived features, and may empower genome-wide searches for genetic polymorphisms that influence brain asymmetry.

  3. Alterations in Sensitivity to Estrogen, Dihydrotestosterone, and Xenogens in B-Lymphocytes from Children with Autism Spectrum Disorder and Their Unaffected Twins/Siblings

    Directory of Open Access Journals (Sweden)

    Martyn A. Sharpe

    2013-01-01

    Full Text Available It has been postulated that androgen overexposure in a susceptible person leads to excessive brain masculinization and the autism spectrum disorder (ASD phenotype. In this study, the responses to estradiol (E2, dihydrotestosterone (DHT, and dichlorodiphenyldichloroethylene (DDE on B-lymphocytes from ASD subjects and controls are compared. B cells were obtained from 11 ASD subjects, their unaffected fraternal twins, and nontwin siblings. Controls were obtained from a different cell bank. Lactate dehydrogenase (LDH and sodium 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl-2H-tetrazolium-5-carboxanilide (XTT reduction levels were measured after incubation with different concentrations of E2, DHT, and DDE. XTT/LDH ratio, representative of mitochondria number per cell, was calculated. E2, DHT, and DDE all cause “U”-shaped growth curves, as measured by LDH levels. ASD B cells show less growth depression compared to siblings and controls (P<0.01. They also have reduced XTT/LDH ratios (P<0.01 when compared to external controls, whereas siblings had values of XTT/LDH between ASD and external controls. B-lymphocytes from people with ASD exhibit a differential response to E2, DHT, and hormone disruptors in regard to cell growth and mitochondrial upregulation when compared to non-ASD siblings and external controls. Specifically, ASD B-lymphocytes show significantly less growth depression and less mitochondrial upregulation when exposed to these effectors. A mitochondrial deficit in ASD individuals is implied.

  4. Genetic and environmental etiologies of reading difficulties: DeFries-Fulker analysis of reading performance data from twin pairs and their nontwin siblings.

    Science.gov (United States)

    Astrom, Raven L; Wadsworth, Sally J; Olson, Richard K; Willcutt, Erik G; Defries, John C

    2012-06-01

    Reading performance data from 254 pairs of identical (MZ) and 420 pairs of fraternal (DZ) twins, 8.0 to 20.0 years of age, were subjected to multiple regression analyses. An extension of the DeFries-Fulker (DF) analysis (DeFries & Fulker, 1985, 1988) that facilitated inclusion of data from 303 of their nontwin siblings was employed. In addition to providing estimates of heritability, this analysis yields a test of the difference between shared environmental influences for twins versus siblings (Astrom et al., 2011). Results suggest that proband reading deficits are due substantially to genetic factors (.67 ± .07, p < .001), and that shared environmental influences are significantly higher for members of twin pairs than for those of twins and their nontwin siblings (viz., .25 versus .17, p = .02).

  5. Fullerton Virtual Twin Study.

    Science.gov (United States)

    Segal, Nancy L

    2006-12-01

    Virtual twins (VTs; same-age unrelated siblings reared together from early infancy) have been studied at California State University (CSU), Fullerton since 1991. The current sample includes over 130 pairs. Past and current research have research have focused on siblings' similarities and differences in general intelligence and body size. Future research in these areas will continue as new pairs continue to be identified. These studies will be supplemented by analyses of personality, social relations and adjustment using monozygotic (MZ) twins, dizygotic (DZ) twins, full siblings and friends, as well as new VTs, who have participated in Twins, Adoptees, Peers and Siblings (TAPS), a collaborative project conducted between CSU Fullerton and the University of San Francisco, from 2002 to 2006.

  6. Age moderates non-genetic influences on the initiation of cannabis use: a twin-sibling study in Dutch adolescents and young adults.

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    Distel, Marijn A; Vink, Jacqueline M; Bartels, Meike; van Beijsterveldt, Catharina E M; Neale, Michael C; Boomsma, Dorret I

    2011-09-01

    To examine the heritability of cannabis initiation, the influence of a possible twin-specific environment and the influence of age on the effects of genes and environment in Dutch adolescents and young adults. Genetic structural equation modelling was used to partition the variance in the liability to cannabis initiation into genetic and environmental components. All participants were registered with the Netherlands Twin Register. A total of 6,208 twins (age 13-20) and 1,545 siblings (age 11-25) from 3,503 families participated in this study. Self-reported cannabis use was assessed prospectively with the Dutch Health Behavior Questionnaire. At the median age of the sample (16.5), genetic factors explained 40% of the individual differences in liability to cannabis initiation. Twins resembled each other more than non-twin siblings, which could not be attributed to the age difference between non-twin siblings. Environmental influences increased with age. This increase applied to environmental factors shared by twins (47% of the variance), environmental factors shared by twins and siblings (24%) and environmental factors unique to an individual (13%). The heritability of the liability for cannabis initiation is higher in adolescents than in young adults due to a larger contribution of environmental factors in young adults. This is due mainly to environmental factors only shared by twins and those shared by all offspring growing up in the same family, but the contribution of environmental factors specific to individuals is also larger in young adults. © 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.

  7. The Perception of Similarities and Differences among Adolescent Siblings: Identification and Deidentification of Twins and Nontwins

    Science.gov (United States)

    Watzlawik, Meike

    2009-01-01

    During adolescence, identity development reaches its crucial point. Siblings foster the search for their own uniqueness through social comparisons. These comparisons can lead to identification ("I am like you." or "We are special.") as well as deidentification ("I am different from you!"). In this study, 204 siblings were interviewed to determine…

  8. DeFries-Fulker analysis of longitudinal reading performance data from twin pairs ascertained for reading difficulties and from their nontwin siblings.

    Science.gov (United States)

    Astrom, Raven L; Wadsworth, Sally J; Olson, Richard K; Willcutt, Erik G; DeFries, John C

    2011-09-01

    Reading difficulties are both heritable and stable; however, little is known about the etiology of this stability. Results from a preliminary analysis of data from 56 twin pairs who participated in the Colorado Longitudinal Twin Study of Reading Disability (Astrom et al., Twin Res Hum Genet 10:434-439, 2007) suggested that about two-thirds of the proband deficit at follow-up was due to genetic factors that also influenced deficits at their initial assessment. Although our proband sample is now nearly twice as large, it is still relatively small; thus, to increase power, we subjected data from probands, co-twins and their nontwin siblings to a novel extension of DeFries-Fulker analysis (DeFries and Fulker, Behav Genet 15:467-473, 1985; DeFries and Fulker, Acta Genet Med Gemellol, 37, 205-216, 1988). In addition to providing estimates of univariate and bivariate heritability, this analysis facilitates a test of the difference between shared environmental influences for twins versus siblings. Longitudinal composite reading performance scores at 10.6 and 15.5 years of age, on average, were analyzed from 33 MZ and 64 DZ twin pairs in which at least one member of each pair had reading difficulties, and from 44 siblings of the probands. Scores were highly stable (.86 ± .03, across probands, co-twins and siblings) and heritability of the group deficit at initial assessment was .67 ± .22. Longitudinal bivariate heritability was .59 ± .21, suggesting that nearly 60% of the proband reading deficit at follow-up is due to genetic factors that influenced reading difficulties at the initial assessment. However, tests for special twin environmental influences were nonsignificant.

  9. Fullerton Virtual Twin Study: an update.

    Science.gov (United States)

    Segal, Nancy L; McGuire, Shirley A; Graham, Jamie L; Stohs, Joanne Hoven

    2013-02-01

    Virtual twins (VTs) are same-age unrelated siblings reared together from early infancy. These unique sibling sets replicate twinship, but without the genetic link. The first VT pair was identified and studied at the University of Minnesota in 1990, launching the development of the Fullerton Virtual Twin Study at California State University, Fullerton (CSUF) in 1991. The registry currently includes 151 pairs, mostly children, with new pairs identified on a continuous basis. Research with VTs includes studies of general intelligence, body size, interpersonal trust, social coordination, social networks, and parenting. In some cases, VTs have been studied in conjunction with pairs of monozygotic twins, dizygotic twins, full siblings, and friends as part of TAPS (Twins, Adoptees, Peers and Siblings), a collaborative project conducted between CSUF and the University of San Francisco, 2002-2006. VTs will also serve as a comparison group for epigenetic analyses of young Chinese twins reared apart and together.

  10. A study of the birth weight-obesity relation using a longitudinal cohort and sibling and twin pairs.

    Science.gov (United States)

    The, Natalie S; Adair, Linda S; Gordon-Larsen, Penny

    2010-09-01

    Sibling and twin study designs provide control for confounding factors that are typically unmeasured in traditional cohort studies. Using nationally representative data from the National Longitudinal Study of Adolescent Health collected at 3 visits during 1994-2002, the authors evaluated the longitudinal association between birth weight and later obesity in a traditional cohort study (n = 13,763; ages 11-21 years at baseline), controlling for sex, age, race/ethnicity, and parental education. Among persons with a nonobese mother, high birth weight (>4 kg) participants were more likely than normal birth weight (>/=2.5-the authors examined longitudinal within-pair differences. Birth weight difference was positively associated with body mass index difference later in life for female monozygotic pairs only (beta = 2.67, 95% confidence interval: 0.99, 4.35). Given the null associations observed in the sibling sample, the commonly observed positive association between birth weight and later obesity from cohort analyses may be attributed to confounding by maternal characteristics. Further research is needed to identify specific factors that contribute to the birth weight-obesity relation.

  11. 判别函数在同胞鉴定中的应用%The application of discriminant functions method in full sibling and half sibling identification

    Institute of Scientific and Technical Information of China (English)

    陈子翔; 王福振; 陆惠玲; 章雅清

    2012-01-01

    Objective To investigate the application of discriminant functions method in full sibling and half sibling identification. Methods 360, 90 and 360 pairs of full siblings ( FS ) , half siblings ( HS ) and unrelated individuals ( UR) were genotyped by PowerPlexTM 16 system. The locus numbers of no-allele sharing( X0), halfallele sharing (X1) and two-alleles sharing ( X2) were calculated, respectively. The relationship judgments of the investigated full siblings, half siblings or unrelated individuals depended on the calculation results of the discriminant functions published in our previous. Results The accuracy of these discriminant iunctions ranged from 83. 06% to 98. 61 % , with the highest one in full sibship-unrelated individual groups. Conclusion It is showed that the studied discriminant functions, especially those for full siblings-unrelated individuals, are effective in sibling identification with comparatively high accuracy.%目的 探讨判别函数法在全同胞与半同胞鉴定中的应用价值.方法 根据360对全同胞、90对半同胞及360对无关个体的15个STR基因座分型结果,计算全不同(X0)、半相同(X1)和完全相同(X2)的基因座数目,分别根据DFS1=3.898X0+3.973X1 - 19.481,DHS1=5.687X0+5.300X1 -35.112及DR1=7.309X0+5.533X1 - 44.941的全同胞/半同胞/无关个体判别函数、DFS2 =3.872X0 +3.931X1 - 18.895及DR2 =7.303X0 +5.473X1-44.298全同胞/无关个体判别函数和DHS3=10.227X0+10.436X1 -66.102及DR3=11.863X0+ 11.089X1 -79.494半同胞/无关个体判别函数进行判别.结果 判别准确率:①用全同胞/半同胞/无关个体判别函数,全同胞组为83.61%,半同胞组为81.11%,无关个体组为83.06%;②用全同胞/无关个体判别函数,全同胞组为96.39%,无关个体组为98.61%;③用半同胞/无关个体判别函数,半同胞组为88.89%,无关个体组为85.00%.结论 本文3种判别函数可应用于同胞鉴定,尤其运用全同胞/无关个体判别函数判断

  12. Ocular manifestations of Noonan syndrome in twin siblings: A case report of keratoconus with acute corneal hydrops

    Directory of Open Access Journals (Sweden)

    Anna Lee

    2014-01-01

    Full Text Available Ocular manifestations of Noonan syndrome (NS in a set of healthy 20-year-old African-American fraternal twins are reported with emphasis on a rare finding of keratoconus with acute corneal hydrops in one twin. Both the twins had learning disabilities and attended a special needs school. Evaluation included visual acuity assessment, tonometry and external eye, slit lamp and dilated fundus examinations, topography with Pentacam and external photographs. The first case was more remarkable as keratoconus with acute corneal hydrops was observed. The patient presented with severe cloudy vision that had worsened over a span of 1 month. It improved significantly on follow-up. The second case included a unique constellation of ocular pathology that highlights the diversity of NS manifestations even amongst twins. Conservative treatment of keratoconus with acute corneal hydrops in a NS patient helped largely resolve the patient′s condition. We report the diverse spectrum of ocular manifestations associated with this rare congenital disorder.

  13. A longitudinal twin and sibling study of the hopelessness theory of depression in adolescence and young adulthood.

    Science.gov (United States)

    Waszczuk, M A; Coulson, A E; Gregory, A M; Eley, T C

    2016-07-01

    Maladaptive cognitive biases such as negative attributional style and hopelessness have been implicated in the development and maintenance of depression. According to the hopelessness theory of depression, hopelessness mediates the association between attributional style and depression. The aetiological processes underpinning this influential theory remain unknown. The current study investigated genetic and environmental influences on hopelessness and its concurrent and longitudinal associations with attributional style and depression across adolescence and emerging adulthood. Furthermore, given high co-morbidity between depression and anxiety, the study investigated whether these maladaptive cognitions constitute transdiagnostic cognitive content common to both internalizing symptoms. A total of 2619 twins/siblings reported attributional style (mean age 15 and 17 years), hopelessness (mean age 17 years), and depression and anxiety symptoms (mean age 17 and 20 years). Partial correlations revealed that attributional style and hopelessness were uniquely associated with depression but not anxiety symptoms. Hopelessness partially mediated the relationship between attributional style and depression. Hopelessness was moderately heritable (A = 0.37, 95% confidence interval 0.28-0.47), with remaining variance accounted for by non-shared environmental influences. Independent pathway models indicated that a set of common genetic influences largely accounted for the association between attributional style, hopelessness and depression symptoms, both concurrently and across development. The results provide novel evidence that associations between attributional style, hopelessness and depression symptoms are largely due to shared genetic liability, suggesting developmentally stable biological pathways underpinning the hopelessness theory of depression. Both attributional style and hopelessness constituted unique cognitive content in depression. The results inform molecular

  14. Alterations in sensitivity to estrogen, dihydrotestosterone, and xenogens in B-lymphocytes from children with autism spectrum disorder and their unaffected twins/siblings.

    Science.gov (United States)

    Sharpe, Martyn A; Gist, Taylor L; Baskin, David S

    2013-01-01

    It has been postulated that androgen overexposure in a susceptible person leads to excessive brain masculinization and the autism spectrum disorder (ASD) phenotype. In this study, the responses to estradiol (E2), dihydrotestosterone (DHT), and dichlorodiphenyldichloroethylene (DDE) on B-lymphocytes from ASD subjects and controls are compared. B cells were obtained from 11 ASD subjects, their unaffected fraternal twins, and nontwin siblings. Controls were obtained from a different cell bank. Lactate dehydrogenase (LDH) and sodium 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) reduction levels were measured after incubation with different concentrations of E2, DHT, and DDE. XTT/LDH ratio, representative of mitochondria number per cell, was calculated. E2, DHT, and DDE all cause "U"-shaped growth curves, as measured by LDH levels. ASD B cells show less growth depression compared to siblings and controls (P ratios (P < 0.01) when compared to external controls, whereas siblings had values of XTT/LDH between ASD and external controls. B-lymphocytes from people with ASD exhibit a differential response to E2, DHT, and hormone disruptors in regard to cell growth and mitochondrial upregulation when compared to non-ASD siblings and external controls. Specifically, ASD B-lymphocytes show significantly less growth depression and less mitochondrial upregulation when exposed to these effectors. A mitochondrial deficit in ASD individuals is implied.

  15. Full scale monitoring of the twin chimneys of the rovinari power plant

    Directory of Open Access Journals (Sweden)

    Bayati I.

    2015-01-01

    Full Text Available The presented paper deals with the structural identification and monitoring of two twin chimneys in very close arrangement. Due to twin arrangement, important interference effects are expected to modify the chimney response to wind action, causing vortex shedding and state-dependent excitation associated to the oscillatory motion of the leeward chimney, in and out of the windward chimney wake. The complexity of the physics of this problem is increased by the dependency of the aerodynamics of circular cylinders on Reynolds number; however, there is a weakness of literature about cylinders behaviour at critical and super-critical range of Reynolds number, due to experimental limitations. Also the International Committee on Industrial Chimneys (CICIND does not provide, at present, any specific technical guideline about twin chimneys whose interaxis distance is less or equal two times the diameter, as in this case. For this reason a Tuned Mass Damper (TMD has been installed in order to increase the damping of the chimney, as merely suggested. This work aims at assessing the effectiveness of the installed TMD and characterizing the tower dynamic behaviour itself due to the wind excitation, as well as providing full scale measurements for twin cylinders configuration at high Reynolds numbers.

  16. Twin birth order, birthweight and birthweight discordance: any relationship

    Directory of Open Access Journals (Sweden)

    Onyiriuka A.N.

    2010-12-01

    Full Text Available Background: It is widely believed that in twin pairs, at birth, the first-born weigh more than the second-born but this concept has been challenged. Objective: To assess the truthfulness of this common concept that first-born twins are usually heavier than their second-born siblings at birth. Methods: In a series of 104 sets of live-born twins, the birth weights of first-born twins were compared with those of their second-born siblings, after controlling for gender. Their intra-pair birthweight differences were determined and twin pairs whose birthweight difference was 15% or more were designated as discordant. Results: Twin I was heavier than Twin II in 61.5% of cases while Twin II was heavier than Twin I in 28.9% of cases. Twins I and II had equal birthweights in 9.6% of cases. Comparing the mean birthweight of the first-born-male twin with that of second-born- male twin, it was 2515+427g (95% Confidence Interval, CI=2402-2628 versus 2432 +435g (95% CI=2321-2543 p>0.05. The mean birthweight of first-born-female twin was 2326+445g (95% CI=2214-2439 while that of the second-born-female twin was 2325+501g (95% CI=2197-2453 p>0.05. When the birthweight difference exceeded 750g, the probability that Twin I will be heavier than Twin II was 83.3% (5 of 6. Conclusion: Although the first-born twin was more often heavier than their second-born siblings, either could weigh more or less at birth. The larger the birthweight difference between growth-discordant twin pair, the greater the probability that the heavier twin would be delivered first

  17. Algorithms of Likelihood Ratio for Discriminating Full Sibling from Half Sibling%全同胞与半同胞关系甄别中似然比的算法

    Institute of Scientific and Technical Information of China (English)

    赵书民; 张琳娜; 张素华; 张娜; 赵珍敏; 李成涛

    2012-01-01

    目的 推导单亲参与及双亲皆无情形下甄别全同胞与半同胞关系时似然比的计算公式. 方法 分别建立单亲参与和双亲皆无情形下进行全同胞与半同胞关系甄别的检验假设,依据贝叶斯原理计算原假设与备择假设对应的遗传学证据的条件概率,并对备择假设与原假设条件下的遗传学证据的条件概率比值进行化简.通过实际案例对推导得到的似然比计算公式进行验证.结果 若有单亲参与,两名孩子在同一基因座共有14种不同的基因型组合,对应的似然比计算公式有5种;若双亲皆无,则共有11种不同的基因型组合,对应的似然比计算公式有7种.单亲参与时,所建立的似然比算法的把握度要高于全同胞指数与半同胞指数比值法.结论 获得的不同情形下甄别全同胞与半同胞的似然比计算公式对于相关案例的鉴定具有实际应用价值.%Objective To derive the formulae for likelihood ratio calculation in discriminating full sibling from half sibling with single-parent participation or without parent participation. Methods Null hypothesis and alternative hypothesis were established for discriminating full sibling from half sibling in two circumstances: two children with single-parent and without parent participation. Conditional probabilities of the genetic evidentiary under null and alternative hypotheses were calculated according to the Bayesian theory. The likelihood ratios were established with the conditional probability under alternative hypothesis division that under null hypothesis, followed with simplification. All the formulae were validated in a real case. Results While mother or fathers' genetic information available in differentiating full sibling from half sibling, 14 different genotype combinations could be shared by the two detected children at a given locus and the likelihood ratio could be calculated with 5 different formulae respectively. While both parents

  18. Risk of epilepsy and autism in full and half siblings-A population-based cohort study.

    Science.gov (United States)

    Christensen, Jakob; Overgaard, Morten; Parner, Erik T; Vestergaard, Mogens; Schendel, Diana

    2016-12-01

    Epilepsy and autism spectrum disorder (ASD) often occur together in the same individual. However, it remains unknown whether siblings of children with ASD have an increased risk of epilepsy and vice versa. This study determines the risk of ASD and epilepsy among younger siblings of children with ASD and epilepsy. The study included all children born in Denmark between January 1, 1980 and 31 December 2006 who participated in follow-up until December 31, 2012 (1,663,302 children). We used Cox regression to calculate the adjusted hazard ratio (aHR) and the Kaplan-Meier method to calculate the cumulative incidence. The overall aHR of epilepsy in younger siblings increased by 70% (aHR 1.70, 95% confidence interval [CI] 1.34-2.16%) if the older sibling had ASD compared with siblings where the older sibling did not have ASD. The cumulative incidence of epilepsy at 20 years of age was 2.54% (95% CI 1.97-3.26%) if the older sibling had ASD, whereas the cumulative incidence of epilepsy at 20 years of age was 1.63% (95% CI 1.60-1.66%) if the older sibling did not have ASD. The overall aHR of ASD in younger siblings increased by 54% if the older sibling had epilepsy (aHR 1.54, 95% CI 1.32-1.80) compared with siblings where the older sibling did not have epilepsy. The cumulative incidence of ASD at 20 years of age was 2.06% (95% CI 1.84-2.32%) if the older sibling had epilepsy, whereas the cumulative incidence of ASD at 20 years of age was 1.27% (95% CI 1.25-1.29%) if the older sibling did not have epilepsy. The cross-disorder sibling risk of epilepsy and ASD was increased for the two disorders, which suggests that genes or environmental factors shared by family members may play a causal role in the co-occurrence of ASD and epilepsy. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

  19. Risk of epilepsy and autism in full and half siblings-A population-based cohort study

    DEFF Research Database (Denmark)

    Christensen, Jakob; Overgaard, Morten; Parner, Erik T;

    2016-01-01

    OBJECTIVE: Epilepsy and autism spectrum disorder (ASD) often occur together in the same individual. However, it remains unknown whether siblings of children with ASD have an increased risk of epilepsy and vice versa. This study determines the risk of ASD and epilepsy among younger siblings of chi...

  20. The availability of full match sibling donors and feasibility of allogeneic bone marrow transplantation in Brazil

    Directory of Open Access Journals (Sweden)

    Eid K.A.B.

    2003-01-01

    Full Text Available The feasibility of allogeneic bone marrow transplantation (alloBMT in a developing country has not yet been demonstrated. Many adverse factors including social and economic limitations may reduce the overall results of this complex and expensive procedure. Our objective was to characterize the most important clinical, social and economic features of candidates for transplantation and their potential donors as well as the influence of these factors on overall survival in a retrospective and exploratory analysis at a university hospital. From July 1993 to July 2001, candidates for BMT were referred to the Bone Marrow Transplantation Unit by Hematology and Oncology Centers from several regions of Brazil. A total of 1138 patients were referred to us as candidates for alloBMT. Median age was 25 years (range: 2 months-60 years, 684 (60.1% were males and 454 (39.9% were females. The clinical indications were severe aplastic anemia and hematological malignancies. From the total of 1138 patients, 923 had HLA-typing; 497/923 (53.8% candidates had full match donors; 352/1138 (30.8% were eligible for alloBMT. Only 235 of 352 (66.7% were transplanted. Schooling was 1st to 8th grade for 123/235 (52.3%; monthly family income ranged from US$60 (7% to more than US$400 (36%. Overall survival for patients with chronic myeloid leukemia, severe aplastic anemia and acute myeloid leukemia was 58, 60 and 30%, respectively. Thus, overall survival rates for the most frequent hematological diseases were similar to those reported in the International Registry, except for acute myeloid leukemia. This descriptive and exploratory analysis suggests the feasibility of alloBMT in a developing country like Brazil.

  1. Brain Magnetic Resonance Imaging of Siblings from Families with Two or More Children with Learning or Intellectual Disabilities and Need for Full-Time Special Education

    Energy Technology Data Exchange (ETDEWEB)

    Mannerkoski, M.; Heiskala, H.; Aaberg, L. (Child Neurology, HUCH Dept. of Pediatric and Adolescent Medicine, Helsinki (Finland)); Raininko, R. (Dept. of Radiology, Uppsala Univ., Uppsala (Sweden)); Sarna, S. (Dept. of Public Health, Univ. of Helsinki, Helsinki (Finland)); Wirtavuori, K. (HUCH Dept. of Pediatric and Adolescent Medicine, Helsinki (Finland)); Autti, T. (HUCH Helsinki Medical Imaging Center, Helsinki (Finland))

    2009-05-15

    Background: Several factors are involved in determining a child's need for special education (Sweden). Thus, the value of brain magnetic resonance imaging (MRI) for subjects with learning and intellectual disabilities is uncertain. Purpose: To evaluate the usefulness of MRI in the diagnostic process of siblings with learning and intellectual disabilities and need for full-time SE. Material and Methods: Altogether, 119 siblings (mean age 11.9 years) from families in which two or more children attended/had previously attended full-time SE underwent prospective brain MRI. SE grouping included three levels, from specific learning disabilities (level 1) to global intellectual disabilities (level 3). Forty-three controls (level 0, mean age 12.0 years) attended mainstream education groups. Signal intensity and structural abnormalities were analyzed, and areas of the cerebrum, posterior fossa, corpus callosum, vermis and brain stem, and diameters of the corpus callosum were measured. In analyses, all area measurements were calculated in proportion to the total inner skull area. Results: Abnormal finding in MRI was more common for siblings (n=62; 52%) in SE (58% for level 3; 49% for level 2; 35% for level 1) than for controls (n=13; 16%). The siblings showed enlarged supra- (P<0.001) and infratentorial (P=0.015) cerebrospinal fluid (CSF) spaces and mild corpus callosum abnormalities (P=0.003) compared to controls. Siblings in SE had smaller inner skull area than controls (P<0.001). Further, the relative area of the mesencephalon (P=0.027) and the diameter of the body of the corpus callosum (P=0.015) were significantly smaller than in controls. In binary logistic regression analysis, enlarged supratentorial CSF spaces increased the probability of SE (odds ratio 4.2; P=0.023). Conclusion: Subjects with learning and intellectual disabilities commonly have more MRI findings than controls. Enlarged supratentorial CSF spaces were a frequent finding in siblings in full

  2. A twin sibling with Prader-Willi syndrome caused by uniparental disomy conceived after in vitro fertilization.

    Science.gov (United States)

    Atik, T; Aykut, A; Karaca, E; Onay, H; Ozkinay, F; Cogulu, O

    2014-01-01

    The use of assisted reproductive technologies (ART) has increased gradually in the treatment of infertility worldwide. On the other hand ART has been found to be associated with an increased risk of congenital malformations including imprinting defects as well. Although a number of imprinting syndromes have been reported to be related with ART, no case with uniparental disomy (UPD) caused Prader-Willi syndrome (PWS) [OMIM ID: 176270] has been reported in the literature. Here we present a dizygotic twin in which one of them was born with maternal UPD15 following ART. The proband was a 2-year-old boy who had feeding difficulties, generalized hypotonia, frontal bossing, broad forehead, small hands and feet. Laboratory investigations revealed minimal dilatation in 3rd and 4th ventricles and corpus callosum hypoplasia in magnetic resonance imaging, supravalvular pulmonary stenosis in echocardiography and pelvicaliectasia in the USG examinations. Methylation and microsatellite markers analyses showed maternal UPD for chromosome 15. Here we report, for the first time UPD caused PWS patient born after ART.

  3. The Sex Ratio of Full and Half Siblings of People Diagnosed With ADHD in Childhood and Adolescence

    DEFF Research Database (Denmark)

    Mouridsen, Svend Erik Birkebæk; Rich, Bente; Isager, Torben

    2014-01-01

    Objective:It has been suggested that high levels of prenatal testosterone exposure are implied in the etiology of male preponderance disorders such as autism spectrum disorder and ADHD. Within this scope, we studied the sex ratio (proportion of males) in siblings of individuals diagnosed with ADHD...... in childhood and adolescence. Method: We did a nationwide, register-based cohort study of the sex ratio in siblings of the 16,381 patients in Denmark diagnosed with ADHD at age 17 years and younger and registered in the nationwide Danish Psychiatric Central Register between January 1, 1994 and May 28, 2013....... Results: Among the 33,151 siblings, 17,041 were males and 16,110 females. This yields a sex ratio of 0.514, which is not statistically significant different from the Danish live birth sex ratio of 0.513 during the relevant years (p = .70). Conclusion: These findings provide no support for the hypothesis...

  4. Six homosexual siblings.

    Science.gov (United States)

    Dank, B M

    1971-09-01

    A family consisting of several homosexual siblings is reported. All ten of the siblings in this family were to some degree homosexually experienced. Six were homosexual or predominantly homosexual, and five had a homosexual identity. The sex composition of the family was three females and seven males. Of the three females, one was homosexual, one was bisexual, and one had had some homosexual experience. There was one set of male dizygotic twins concordant for homosexuality in the family. All ten siblings were exposed to relatively similar family dynamics. The father's behavior toward the children and his wife was characterized by hostility, violence, and alcoholism. He was eventually murdered when the youngest child was 6 years old. The mother demonstrated qualities that were essentially opposite those of the father. She was described as affectionate and loving toward all the children, and she did not display violent behavior. The male homosexual sibling who was interviewed displayed a strong identification with his mother via a feminine self-identification, the adoption of the housewife role in a homosexual marriage, and the adoption of the passive role in anal intercourse. Only one other multiple homosexual sibling family has been reported in the scientific literature. This family consisted of 14 siblings, 11 male and three female. The four homosexual siblings in this family were all male and consisted of two sets of dizygotic twins. The behavior of the parents of this family was quite similar to the behavior of the parents in this study-a hostile and violent father and an affectionate and loving mother. These two multiple homosexual sibling families provide support for theories that emphasize the importance of early family relationships in the development of a homosexual adaptation. It is held that multiple homosexual sibling families can be employed as strategic data in testing various etiological theories of homosexuality.

  5. Full-mouth rehabilitation of a case of generalized enamel hypoplasia using a twin-stage procedure

    Directory of Open Access Journals (Sweden)

    Aswini Kumar Kar

    2010-01-01

    Full Text Available The dilemma confronting many dentists today is that innovations and well-defined specializations have greatly enlarged the treatment realm for tooth preservation as well as tooth replacement. The objectives should be preservation of the remaining tooth structure, restoration of optimum function, esthetics with least invasive procedures, cost effective, and short treatment time. The number of remaining natural teeth is one of the most widely used method for evaluating oral health and the prosthetic treatment of patients with a mutilated dentition. Though the treatment of these patients can be complex, but there are some important principles applicable in most cases. This case report demonstrates a satisfying full mouth rehabilitation using the Hobo and Takayama twin-stage procedure for a patient with esthetically and functionally compromised dentition. The final prosthesis with this twin-stage technique ensured a restoration with a predictable posterior disclusion and anterior guidance in harmony with the condylar path.

  6. The Twin Arginine Translocation System Is Essential for Aerobic Growth and Full Virulence of Burkholderia thailandensis

    OpenAIRE

    Wagley, Sariqa; Hemsley, Claudia; Thomas, Rachael; Madeleine G Moule; Vanaporn, Muthita; Andreae, Clio; Robinson, Matthew; Goldman, Stan; Brendan W. Wren; Butler, Clive S.; Richard W Titball

    2014-01-01

    The twin arginine translocation (Tat) system in bacteria is responsible for transporting folded proteins across the cytoplasmic membrane, and in some bacteria, Tat-exported substrates have been linked to virulence. We report here that the Tat machinery is present in Burkholderia pseudomallei, B. mallei, and B. thailandensis, and we show that the system is essential for aerobic but not anaerobic growth. Switching off of the Tat system in B. thailandensis grown anaerobically resulted in filamen...

  7. Assumption-free estimation of heritability from genome-wide identity-by-descent sharing between full siblings.

    Directory of Open Access Journals (Sweden)

    Peter M Visscher

    2006-03-01

    Full Text Available The study of continuously varying, quantitative traits is important in evolutionary biology, agriculture, and medicine. Variation in such traits is attributable to many, possibly interacting, genes whose expression may be sensitive to the environment, which makes their dissection into underlying causative factors difficult. An important population parameter for quantitative traits is heritability, the proportion of total variance that is due to genetic factors. Response to artificial and natural selection and the degree of resemblance between relatives are all a function of this parameter. Following the classic paper by R. A. Fisher in 1918, the estimation of additive and dominance genetic variance and heritability in populations is based upon the expected proportion of genes shared between different types of relatives, and explicit, often controversial and untestable models of genetic and non-genetic causes of family resemblance. With genome-wide coverage of genetic markers it is now possible to estimate such parameters solely within families using the actual degree of identity-by-descent sharing between relatives. Using genome scans on 4,401 quasi-independent sib pairs of which 3,375 pairs had phenotypes, we estimated the heritability of height from empirical genome-wide identity-by-descent sharing, which varied from 0.374 to 0.617 (mean 0.498, standard deviation 0.036. The variance in identity-by-descent sharing per chromosome and per genome was consistent with theory. The maximum likelihood estimate of the heritability for height was 0.80 with no evidence for non-genetic causes of sib resemblance, consistent with results from independent twin and family studies but using an entirely separate source of information. Our application shows that it is feasible to estimate genetic variance solely from within-family segregation and provides an independent validation of previously untestable assumptions. Given sufficient data, our new paradigm will

  8. Assumption-free estimation of heritability from genome-wide identity-by-descent sharing between full siblings.

    Directory of Open Access Journals (Sweden)

    2006-03-01

    Full Text Available The study of continuously varying, quantitative traits is important in evolutionary biology, agriculture, and medicine. Variation in such traits is attributable to many, possibly interacting, genes whose expression may be sensitive to the environment, which makes their dissection into underlying causative factors difficult. An important population parameter for quantitative traits is heritability, the proportion of total variance that is due to genetic factors. Response to artificial and natural selection and the degree of resemblance between relatives are all a function of this parameter. Following the classic paper by R. A. Fisher in 1918, the estimation of additive and dominance genetic variance and heritability in populations is based upon the expected proportion of genes shared between different types of relatives, and explicit, often controversial and untestable models of genetic and non-genetic causes of family resemblance. With genome-wide coverage of genetic markers it is now possible to estimate such parameters solely within families using the actual degree of identity-by-descent sharing between relatives. Using genome scans on 4,401 quasi-independent sib pairs of which 3,375 pairs had phenotypes, we estimated the heritability of height from empirical genome-wide identity-by-descent sharing, which varied from 0.374 to 0.617 (mean 0.498, standard deviation 0.036. The variance in identity-by-descent sharing per chromosome and per genome was consistent with theory. The maximum likelihood estimate of the heritability for height was 0.80 with no evidence for non-genetic causes of sib resemblance, consistent with results from independent twin and family studies but using an entirely separate source of information. Our application shows that it is feasible to estimate genetic variance solely from within-family segregation and provides an independent validation of previously untestable assumptions. Given sufficient data, our new paradigm will

  9. Sibling interaction.

    Science.gov (United States)

    Balsam, Rosemary H

    2013-01-01

    Sibling interactions traditionally were conceived psychoanalytically in "vertical" and parentified oedipal terms and overlooked in their own right, for complicated reasons (Colonna and Newman 1983). Important work has been done to right this, from the 1980s and onward, with conferences and writings. Juliet Mitchell's 2000 and, in particular, her 2003 books, for example, have brought "lateral" sibling relations forcefully to the forefront of insights, especially about sex and violence, with the added interdisciplinary impact of illuminating upheaval in global community interactions as well as having implications for clinicians. A clinical example from the analysis of an adult woman with a ten-years-younger sister will show here how we need both concepts to help us understand complex individual psychic life. The newer "lateral" sibling emphasis, including Mitchell's "Law of the Mother" and "seriality," can be used to inform the older "vertical" take, to enrich the full dimensions of intersubjective oedipal and preoedipal reciprocities that have been foundational in shaping that particular analysand's inner landscape. Some technical recommendations for heightening sensitivity to the import of these dynamics will be offered along the way here, by invoking Hans Loewald's useful metaphor of the analytic situation as theater.

  10. Familial and Special Twin Influences on Cigarette Use Initiation.

    Science.gov (United States)

    Bares, Cristina B; Maes, Hermine H; Kendler, Kenneth S

    2017-04-01

    Shared experiences within families play an important role in the initiation of cigarette use among adolescents. Behavioral genetic studies using various samples have implicated that the shared environment that twins experience is an important source of influence on whether adolescents initiate cigarette use. Whether the special twin environment, in addition to the shared environment, contributes significantly to making twin siblings more similar in cigarette initiation, and whether the influence of the special twin environment persists into adulthood, is less clear. Data for this study came from the National Longitudinal Survey of Adolescent Health. Twin, full-, and half-sibling pairs between the ages of 12 and 33 were separated into three age groups, with about 3,000 individuals in each age group. The proportion of variance in cigarette use initiation explained by genetic, shared, special twin, and unique environmental factors were examined. The results of separate age-moderated univariate variance decomposition models indicate that the special twin environment does not significantly contribute to the variance in cigarette use initiation in adolescence or young adulthood. Factors shared by individuals in a family, but that are not specific to being a twin, are important in determining whether adolescents will initiate the use of cigarettes.

  11. Sibling Incest.

    Science.gov (United States)

    Phillips-Green, Mary J.

    2002-01-01

    Recently, sibling incest, a type of intrafamilial incest, has received notice from mental health professionals; however, many professionals still do not recognize the seriousness of the problem. This article reviews current research on the individual and family dynamics that allow sibling incest to occur, the effects of sibling incest on victims,…

  12. Familial influences on the full range of variability in attention and activity levels during adolescence: A longitudinal twin study.

    Science.gov (United States)

    Peng, Chun-Zi; Grant, Julia D; Heath, Andrew C; Reiersen, Angela M; Mulligan, Richard C; Anokhin, Andrey P

    2016-05-01

    To investigate familial influences on the full range of variability in attention and activity across adolescence, we collected maternal ratings of 339 twin pairs at ages 12, 14, and 16, and estimated the transmitted and new familial influences on attention and activity as measured by the Strengths and Weaknesses of Attention-Deficit/Hyperactivity Disorder Symptoms and Normal Behavior Scale. Familial influences were substantial for both traits across adolescence: genetic influences accounted for 54%-73% (attention) and 31%-73% (activity) of the total variance, and shared environmental influences accounted for 0%-22% of the attention variance and 13%-57% of the activity variance. The longitudinal stability of individual differences in attention and activity was largely accounted for by familial influences transmitted from previous ages. Innovations over adolescence were also partially attributable to familial influences. Studying the full range of variability in attention and activity may facilitate our understanding of attention-deficit/hyperactivity disorder's etiology and intervention.

  13. The Spread of Substance Use and Delinquency between Adolescent Twins

    Science.gov (United States)

    Laursen, Brett; Hartl, Amy C.; Vitaro, Frank; Brendgen, Mara; Dionne, Ginette; Boivin, Michel

    2017-01-01

    This investigation examines the spread of problem behaviors (substance use and delinquency) between twin siblings. A sample of 628 twins (151 male twin pairs and 163 female twin pairs) drawn from the Quebec Newborn Twin Study completed inventories describing delinquency and substance use at ages 13, 14, and 15. A 3-wave longitudinal actor-partner…

  14. Siblings' personality traits and types of sibling relationship in childhood

    Directory of Open Access Journals (Sweden)

    Tina Kavčič

    2011-01-01

    Full Text Available The contribution presents a follow-up study of sibling relationship and personality in 87 sibling dyads in early/middle childhood from parental perspective. At Time 1 all siblings attended pre-school and one year later approximately half of the older siblings entered compulsory school. At both times of measurement siblings' mothers and fathers independently reported on their children's personality characteristics using the Inventory of Child Individual Differences (Halverson et al., 2003; Slovene adaptation, Zupančič & Kavčič, 2009 and on the observed sibling warmth, agonism, and rivalry using the Parental Expectations and Perceptions of Children's Sibling Relationships Questionnaire (Kramer, 2001. The predictive relationship obtained by two sets of cross-rater analyses (between maternal ratings of child personality and paternal reports on sibling relationship, and vice versa suggested that (a personality traits of both siblings and (b the match between siblings' personalities are associated with sibling type (affectionate, involved or average membership. Among personality traits, disagreeableness seems to be an especially significant contributor to sibling relationship quality.

  15. Maneuverability prediction for a ship with full-revolving twin propellers

    Directory of Open Access Journals (Sweden)

    WU Xingya

    2017-01-01

    Full Text Available To predict the maneuverability of full-revolving propeller ships, this paper analyzes the propeller force and establishes MMG equations for controlling motion mathematical models that are suited to the full-revolving propeller model, in accordance with the modeling method of the separating ship motion model and taking into account the special nature of the force and flexibility of a full rotation in the horizontal plane of a full-revolving propeller. Secondly, hydrodynamic force derivatives for the ship model are obtained by simulating the model's PMM movement, and the controlling Ordinary Differential Equation (ODE is solved using the four-stage Rung-Kuta method. Finally, the numerical simulation of a certain ship's rotating motion and its zigzag test in still water is obtained, and the prediction results are compared with that of a self-running model. It is found that the simulation results agree well with the trial results, and the effectiveness of the ship motion model for the full-revolving propeller model is validated. In brief, this paper provides a reliable and effective method of predicting the maneuverability of full-revolving propeller ships.

  16. A rare case of concomitant hypo-hyperdontia in identical twins

    Directory of Open Access Journals (Sweden)

    Sharma A

    2008-10-01

    Full Text Available Concomitant hypodontia and hyperdontia is a rare condition of unknown etiology. One such case of occurring in identical twins in mixed dentition is presented and discussed. A sibling, especially a twin of an affected patient, should be suspected of having a similar problem, even if he or she is asymptomatic. Genetic factors probably play an important etiological role in the co-occurence of partial anodontia and supernumerary teeth.

  17. Computational and Experimental Study of the Transient Transport Phenomena in a Full-Scale Twin-Roll Continuous Casting Machine

    Science.gov (United States)

    Xu, Mianguang; Li, Zhongyang; Wang, Zhaohui; Zhu, Miaoyong

    2017-02-01

    To gain a fundamental understanding of the transient fluid flow in twin-roll continuous casting, the current paper applies both large eddy simulation (LES) and full-scale water modeling experiments to investigate the characteristics of the top free surface, stirring effect of the roll rotation, boundary layer fluctuations, and backflow stability. The results show that, the characteristics of the top free surface and the flow field in the wedge-shaped pool region are quite different with/without the consideration of the roll rotation. The roll rotation decreases the instantaneous fluctuation range of the top free surface, but increases its horizontal velocity. The stirring effect of the roll rotating makes the flow field more homogenous and there exists clear shear flow on the rotating roll surface. The vortex shedding induced by the Kármán Vortex Street from the submerged entry nozzle (SEN) causes the "velocity magnitude wave" and strongly influences the boundary layer stability and the backflow stability. The boundary layer fluctuations or the "velocity magnitude wave" induced by the vortex shedding could give rise to the internal porosity. In strip continuous casting process, the vortex shedding phenomenon indicates that the laminar flow can give rise to instability and that it should be made important in the design of the feeding system and the setting of the operating parameters.

  18. The Role of Nature and Nurture for Individual Differences in Primary Emotional Systems: Evidence from a Twin Study.

    Directory of Open Access Journals (Sweden)

    Christian Montag

    Full Text Available The present study investigated for the first time the relative importance of genetics and environment on individual differences in primary emotionality as measured with the Affective Neuroscience Personality Scales (ANPS by means of a twin-sibling study design. In N = 795 participants (n = 303 monozygotic twins, n = 172 dizygotic twins and n = 267 non-twin full siblings, moderate to strong influences of genetics on individual differences in these emotional systems are observed. Lowest heritability estimates are presented for the SEEKING system (33% and highest for the PLAY system (69%. Further, multivariate genetic modeling was applied to the data showing that associations among the six ANPS scales were influences by both, a genetic as well as an environmental overlap between them. In sum, the study underlines the usefulness of the ANPS for biologically oriented personality psychology research.

  19. Older Siblings Influence Younger Siblings' Motor Development

    Science.gov (United States)

    Berger, Sarah E.; Nuzzo, Katie

    2008-01-01

    Evidence exists for two competing theories about the effects of having an older sibling on development. Previous research has found that having an older sibling has both advantages and disadvantages for younger siblings' development. This study examined whether and how older siblings influenced the onset of their own younger siblings' motor…

  20. Current twin studies in Germany: report on CoSMoS, SOEP, and ChronoS.

    Science.gov (United States)

    Hahn, Elisabeth; Gottschling, Juliana; Spinath, Frank M

    2013-02-01

    This article summarizes the status of three recent German twin studies: CoSMoS, SOEP, and ChronoS. The German twin study on Cognitive Ability, Self-Reported Motivation, and School Achievement (CoSMoS) is a three-wave longitudinal study of monozygotic and dizygotic twins reared together, and aims to investigate predictors of and influences on school performance. In the first wave of the data collection in 2005, 408 pairs of twins aged between 7 and 11 as well as their parents participated in CoSMoS. The SOEP twin study is an extended twin study, which has combined data from monozygotic and dizygotic twins reared together with additional data from full sibling pairs, mother-child, and grandparent-child dyads who participated in the German Socio-Economic Panel (GSOEP) study. The SOEP twin project comprises about 350 twin and 950 non-twin pairs aged between 17 and 70. Data were collected between 2009 and 2010, with a focus on personality traits, wellbeing, education, employment, income, living situation, life-satisfaction, and several attitudes. The aim of the Chronotype twin study (ChronoS) was to examine genetic and environmental influences on chronotype (morningness and eveningness), coping strategies, and several aspects of the previous SOEP twin project in a sample of 301 twin pairs aged between 19 and 76 years, recruited in 2010 and 2011. Part of the ChronoS twin sample also participated in the earlier SOEP twin study, representing a second wave of assessments. We briefly describe the design and contents of these three studies as well as selected recent findings.

  1. Clinical and genetic study of Wilson's disease in affected twins and siblings%Wilson病双(多)胞胎家系的临床和基因突变研究

    Institute of Scientific and Technical Information of China (English)

    程楠; 王训; 喻绪恩; 周志华; 高伟明; 饶娆; 胡纪源; 杨任民; 韩咏竹

    2013-01-01

    目的 观察双(多)胞胎Wilson病家系的临床和基因突变特点.方法 收集双(多)胞胎Wilson病家系的临床资料,留取其全血标本,提取基因组DNA,应用短串联重复(short tandem repeats,STR)分型判定双胞胎是否为同卵双生,用DNA测序法检测ATP7B基因各外显子的突变.结果 5个双胞胎家系的患者均符合Wilson病的诊断标准.STR分型提示4个家系为同卵双生,1个家系为异卵双生.3个双胞胎家系的患者均以肝症状起病,另外2个家系的患者以脑症状起病.在4个家系的患者中检出ATP7B基因的突变,均位于第8和(或)第13外显子,其中1个家系的患者同时携带第8外显子p.R778W杂合突变和第13外显子p.P992L纯合突变,其父母分别为p.R778W杂合突变和p.P992L杂合突变的携带者,因此该家系的患者发生了杂合丢失现象.有1个家系的2例患者及其父母亲各外显子均未检出突变.1个三胞胎家系中的1名女性成员为脑症状起病的Wilson病患者,1名男性为无症状的亚临床型Wilson病患者,另1例女性成员未患病,这3位成员及其母亲均检出第13外显子p.P992L杂合突变.结论 本研究结果进一步证实了遗传因素在Wilson病发病中的主要作用.杂合丢失现象是除点突变外Wilson病的另一种发病机制.%Objective To study the clinical and genetic characteristics of twins and siblings affected with Wilson's disease (WD).Methods Clinical data and blood samples were collected from the subjects after informed consent was obtained.Genomic DNA was extracted and potential mutations in the exons in ATP7B gene were detected with PCR-DNA sequencing.Short tandem repeat (STR) genotyping was performed to determine the zygosity of the twins.Results The 5 pairs of twins have all met the diagnostic criteria for WD.STR genotyping has confirmed that 4 pairs were monozygotic twins.3 pairs of twins had an onset with liver symptoms,the other 2 had an onset with brain symptoms.ATP7B gene

  2. What Virtual Twins Reveal About General Intelligence and Other Behaviors.

    Science.gov (United States)

    Segal, Nancy L; McGuire, Shirley A; Stohs, Joanne Hoven

    2012-09-01

    The Fullerton Virtual Twin Study has been assessing the behaviors of an unusual sibship since 1982. Virtual twins (VTs) are same-age, unrelated siblings reared together since infancy. They replicate the rearing situation of twins but without the genetic link, enabling direct assessment of shared environmental effects on behavior. An updated analysis of IQ data, based on an increased sample of 142 VT pairs (7.87 years, SD=8.22), is presented. Intraclass correlations of .28 (IQ) and .11 (subtest profile) indicated modest shared environmental influences on intelligence. Findings from the Twins, Adoptees, Peers and Siblings (TAPS) project that studies virtual twins and other kinships are described.

  3. Family matters: happiness in nuclear families and twins.

    Science.gov (United States)

    Nes, Ragnhild Bang; Czajkowski, N; Tambs, K

    2010-09-01

    Biometric studies have shown that happiness is strongly affected by genes. The findings are mainly based on twin data, however, and the full validity of the results has been debated. To overcome some limitations in classical twin research, we examined aetiological sources of subjective well-being (SWB), using two independent population-based samples, one including nuclear families (N = 54,540) and one including twins (N = 6,620). Biometric modelling using R was conducted to test for a data structure implying either non-additive genetic effects or higher environmental co-twin correlation in MZ than DZ pairs (violation of the EEA). We also estimated non-random mating, cultural transmission and shared environments specific for regular siblings and twins. Two sets of nested models were fitted and compared. The best explanatory model shows that family matters for happiness predominantly due to quantitative sex-specific genetic effects, a moderate spousal correlation and a shared twin environment. Upper limits for broad-sense heritability were estimated to be 0.33 (females) and 0.36 (males). Our study constitutes the most elaborate biometric study of SWB to date and illustrates the utility of including responses from multiple types of relatives in quantitative genetic analyses.

  4. The relationship between twin language, twins' close ties, and social competence.

    Science.gov (United States)

    Hayashi, Chisato; Mikami, Hiroshi; Nishihara, Reiko; Maeda, Chiho; Hayakawa, Kazuo

    2014-02-01

    This study investigated the relationship between twin language, twins' close ties, and social competence in a prospective longitudinal study. We hypothesized that twins whose tie is close would be more likely to develop a twin language, and these twins would be less likely to develop social competence. In addition, we hypothesize that some environmental factors, such as having an older sibling, preschool attendance, zygosity, and sex are also related to twin language, twins' close ties, and social competence. At baseline in 1999 a mailed questionnaire survey was conducted, and a follow-up questionnaire was distributed in 2004 among 958 mothers. As a result, 516 respondents returned the questionnaire (53.9%). In this study, we used 261 twin pairs aged from 6 to 12 years (school-age children) for analysis, excluding those with missing values. In the present study, we found that zygosity and sex were associated with twins' close ties. Having an older sibling and preschool attendance did not affect the twins' close tie, twin language, or social competence. One of the most important findings was that social competence was not affected directly by twins' close tie, but was affected when a twin language was found.

  5. Lipoid proteinosis in two siblings

    Directory of Open Access Journals (Sweden)

    Behera Samira Kumar

    2006-01-01

    Full Text Available Lipoid proteinosis denotes a rare autosomal recessive disorder. We report here lipoid proteinosis in a 31-year-old unmarried female along with her sibling. She had hoarseness of voice along with multiple asymptomatic warty papules over face, neck and extremitis with similar findings in one of her siblings. Laryngoscope showed beaded deposits over epiglottis and vocal cords of both patients. Biopsy showed PAS-positive homogeneous eosinophilic materials in upper dermis.

  6. Delivery in Twin Gestation

    Directory of Open Access Journals (Sweden)

    Mark T. Peters

    1995-01-01

    Full Text Available Objective: The objective of this study was to determine whether prophylactic treatment with oral broad-spectrum antimicrobial therapy improves pregnancy outcomes in twin gestations.

  7. Dead or Alive? Knowledge about a Sibling's Death Varies by Genetic Relatedness in a Modern Society

    Directory of Open Access Journals (Sweden)

    Thomas V. Pollet

    2009-01-01

    Full Text Available Using a large sample of non-institutionalized individuals from the Netherlands (n = 7610, we examined the influence of relatedness on an individual's knowledge about whether their sibling is alive or not. Respondents were generally less likely to know whether their sibling was alive if they were not fully related. The effects were stronger for differences between paternal half-siblings and full siblings than for differences between maternal half-siblings and full siblings.

  8. Long-term neurodevelopmental outcome of monochorionic and matched dichorionic twins.

    Directory of Open Access Journals (Sweden)

    Karien E A Hack

    Full Text Available BACKGROUND: Monochorionic (MC twins are at increased risk for perinatal mortality and serious morbidity due to the presence of placental vascular anastomoses. Cerebral injury can be secondary to haemodynamic and hematological disorders during pregnancy (especially twin-to-twin transfusion syndrome (TTTS or intrauterine co-twin death or from postnatal injury associated with prematurity and low birth weight, common complications in twin pregnancies. We investigated neurodevelopmental outcome in MC and dichorionic (DC twins at the age of two years. METHODS: This was a prospective cohort study. Cerebral palsy (CP was studied in 182 MC infants and 189 DC infants matched for weight and age at delivery, gender, ethnicity of the mother and study center. After losses to follow-up, 282 of the 366 infants without CP were available to be tested with the Griffiths Mental Developmental Scales at 22 months corrected age, all born between January 2005 and January 2006 in nine perinatal centers in The Netherlands. Due to phenotypic (unalikeness in mono-or dizygosity, the principal investigator was not blinded to chorionic status; perinatal outcome, with exception of co-twin death, was not known to the examiner. FINDINGS: Four out of 182 MC infants had CP (2.2% - two of the four CP-cases were due to complications specific to MC twin pregnancies (TTTS and co-twin death and the other two cases of CP were the result of cystic PVL after preterm birth - compared to one sibling of a DC twin (0.5%; OR 4.2, 95% CI 0.5-38.2 of unknown origin. Follow-up rate of neurodevelopmental outcome by Griffith's test was 76%. The majority of 2-year-old twins had normal developmental status. There were no significant differences between MC and DC twins. One MC infant (0.7% had a developmental delay compared to 6 DC infants (4.2%; OR 0.2, 95% 0.0-1.4. Birth weight discordancy did not influence long-term outcome, though the smaller twin had slightly lower developmental scores than its

  9. Conjoined Twins

    Science.gov (United States)

    ... sites of conjoined twins. Abdomen. Omphalopagus (om-fuh-LOP-uh-gus) twins are joined near the bellybutton. ... brain tissue. Head and chest. Cephalopagus (sef-uh-LOP-uh-gus) twins are joined at the face ...

  10. Twin-twin Transfusion Syndrome with a Single Ectopic Kidney in a Twin Donor. Case Presentation

    Directory of Open Access Journals (Sweden)

    Gerardo Rogelio Robaina Castellanos

    2016-10-01

    Full Text Available Twin-twin Transfusion Syndrome presents more frequently in diamniotic monochromic twins. In advanced stages and without prenatal intervention, is associated to high rates of peri natal mortality and neurological sequel in the survivors. It is presented a case of a pair of twins with severe depression at birth in which it was diagnosed a Twin-twin Transfusion Syndrome, later confirmed with the presence of anemia in the donor twin and polycythemia in the receptor twin. Both twins had an unfavourable evolution with an early neonatal death. Necropsy findings were comparable with secondary damage to the syndrome, with the particularity that both had evidences of pulmonary infection and a renal malformation in the donor twin which is not included in the proper malformations of this syndrome. The objective of this work is to point out the essential elements for the diagnosis and antenatal treatment for this disease through the peculiarities of the presented case.

  11. Twins eye study in Tasmania (TEST): rationale and methodology to recruit and examine twins.

    Science.gov (United States)

    Mackey, David A; Mackinnon, Jane R; Brown, Shayne A; Kearns, Lisa S; Ruddle, Jonathan B; Sanfilippo, Paul G; Sun, Cong; Hammond, Christopher J; Young, Terri L; Martin, Nicholas G; Hewitt, Alex W

    2009-10-01

    Visual impairment is a leading cause of morbidity and poor quality of life in our community. Unravelling the mechanisms underpinning important blinding diseases could allow preventative or curative steps to be implemented. Twin siblings provide a unique opportunity in biology to discover genes associated with numerous eye diseases and ocular biometry. Twins are particularly useful for quantitative trait analysis through genome-wide association and linkage studies. Although many studies involving twins rely on twin registries, we present our approach to the Twins Eye Study in Tasmania to provide insight into possible recruitment strategies, expected participation rates and potential examination strategies that can be considered by other researchers for similar studies. Five separate avenues for cohort recruitment were adopted: (1) piggy-backing existing studies where twins had been recruited, (2) utilizing the national twin registry, (3) word-of-mouth and local media publicity, (4) directly approaching schools, and finally (5) collaborating with other research groups studying twins.

  12. Familial aggregation of atrial fibrillation: a study in Danish twins

    DEFF Research Database (Denmark)

    Christophersen, Ingrid Elisabeth; Ravn, Lasse Steen; Budtz-Joergensen, Esben

    2009-01-01

    BACKGROUND: Heritability may play a role in nonfamilial atrial fibrillation (AF). We hypothesized that a monozygotic (MZ) twin whose co-twin was diagnosed with AF would have an increased risk of the disease compared with a dizygotic (DZ) twin in the same situation. METHODS AND RESULTS: A sample...... of 1137 same-sex twin pairs (356 MZ and 781 DZ pairs) in which one or both members were diagnosed with AF were identified in The Danish Twin Registry. Concordance rates were twice as high for MZ pairs than for DZ pairs regardless of sex (22.0% versus 11.6%, P...-free survival times, we compared the time span between occurrences of disease in MZ and DZ twins. The unaffected twin was included when his or her twin-sibling (the index twin) was diagnosed with AF. After adjustment for age at entry, MZ twins had a significantly shorter event-free survival time (hazard ratio...

  13. Discordancia de peso al nacer: consecuencias y su perdurabilidad en el desarrollo psicológico del gemelo de menor peso intrapar (Intertwin birth weight discordance: its effects and their persistence in the psychological development of the lightest intrapair twin

    Directory of Open Access Journals (Sweden)

    Elena Escolano-Pérez

    2015-08-01

    Full Text Available More twins are being born with intrapair birth weight discordances. Discordance in birth weight is a risk factor that can affect the development of twins, especially that of the lightest twin. However, few studies have analysed the possible consequences of birth weight discordance on the lightest twin beyond possible neonatal obstetric problems. Thus,little is known about the consequences of birth weight discordance on the psychological development of such babies.This article reviews the literature and summarizes the effects of birth weight discordance on the psychological development of the lightest intrapair twins compared with their heavier twin siblings and the persistence of these effects during their lifetime. The literature shows that the lightest intrapair twins obtain lower scores than their siblings in cognitive, verbal, and psychomotor skills. They are also more likely to have traits associated with the development of hyperactivity. These differences persist from childhood to youth. There is no information about adulthood. In conclusion, birth weight discordance has marked effects on the psychological development of intrapair lower weight twins, both in relation to the affected dimensions and the persistence of these effects over time. Further research is needed on designing early preventative interventions that would optimize the development of these children. This proposal is of relevance, given that the optimal development of all children is the basis of a society in continuous progress.

  14. ACARDIAC TWIN

    OpenAIRE

    Vinayachandran; Jyothi,; Bindu; Umadevi

    2014-01-01

    Acardiac twin is a very rare complication occurring in monozygotic twins in which one fetus develops normally (pump twin) and the other (recipient twin) demonstrate cardiac non development and othe r anomalies. This may represent an extreme form of TTTS, also referred to as TRAP sequence. 1,2,

  15. Adult body height of twins compared with that of singletons: a register-based birth cohort study of Norwegian males.

    Science.gov (United States)

    Eriksen, Willy; Sundet, Jon M; Tambs, Kristian

    2013-05-01

    In the present study, we evaluated whether childhood differences in body height between singletons and twins persist into adulthood. Data from the Medical Birth Register of Norway were linked with data from the Norwegian National Conscript Service. This study used data on the 457,999 males who were born alive and without physical anomalies in single or twin births in Norway during 1967-1984 and who were examined at the mandatory military conscription (age 18-20 years; 1985-2003). For sibling comparisons, the authors selected the 1,721 sibships of full brothers that included at least 1 male born in a single birth and at least 1 male born in a twin birth (4,520 persons, including 2,493 twins and 2,027 singletons). An analysis of the total study population using generalized estimating equations showed that the twins were 0.6 cm (95% confidence interval: 0.4, 0.7) shorter than were the singletons after adjustment for a series of background factors. The fixed-effects regression analysis of the sibships that included both twins and singletons showed that the twins were 0.9 cm (95% confidence interval: 0.6, 1.2) shorter than were their singleton brothers. The study suggests that male twins born in Norway during 1967-1984 were slightly shorter in early adulthood than were singletons.

  16. A twin and molecular genetics study of sleep paralysis and associated factors.

    OpenAIRE

    Denis, Dan; French, Christopher C.; Rowe, Richard; Zavos, Helena M S; Nolan, Patrick M.; Parsons, Michael J.; Gregory, Alice M

    2015-01-01

    Sleep paralysis is a relatively common but under-researched phenomenon. In this paper we examine prevalence in a UK sample and associations with candidate risk factors. This is the first study to investigate the heritability of sleep paralysis in a twin sample and to explore genetic associations between sleep paralysis and a number of circadian expressed single nucleotide polymorphisms. Analyses are based on data from the Genesis1219 twin/sibling study, a community sample of twins/siblings fr...

  17. A twin and molecular genetics study of sleep paralysis and associated factors.

    OpenAIRE

    Denis, Dan; French, Christopher C.; Rowe, Richard; Zavos, Helena M. S.; Nolan, Patrick M.; Parsons, Michael J.; Gregory, Alice M.

    2015-01-01

    Sleep paralysis is a relatively common but under-researched phenomenon. In this paper we examine prevalence in a UK sample and associations with candidate risk factors. This is the first study to investigate the heritability of sleep paralysis in a twin sample and to explore genetic associations between sleep paralysis and a number of circadian expressed single nucleotide polymorphisms. Analyses are based on data from the Genesis1219 twin/sibling study, a community sample of twins/siblings fr...

  18. Personality and Sibling Relationships.

    Science.gov (United States)

    Furman, Wyndol; Lanthier, Richard P.

    1996-01-01

    This study examined the role personality variables play in sibling relationships. It proposed that the characteristics of sibling relationships are influenced by: family constellation variables such as birth order, gender, and age spacing; parent-child relationships including quality of relationship and parent management of siblings; and the…

  19. A Twin-Family Study of General IQ

    Science.gov (United States)

    van Leeuwen, Marieke; van den Berg, Stephanie M.; Boomsma, Dorret I.

    2008-01-01

    In this paper we assess the presence of assortative mating, gene-environment interaction and the heritability of intelligence in childhood using a twin family design with twins, their siblings and parents from 112 families. We evaluate two competing hypotheses about the cause of assortative mating in intelligence: social homogamy and phenotypic…

  20. A Twin-Family Study of General IQ

    Science.gov (United States)

    van Leeuwen, Marieke; van den Berg, Stephanie M.; Boomsma, Dorret I.

    2008-01-01

    In this paper we assess the presence of assortative mating, gene-environment interaction and the heritability of intelligence in childhood using a twin family design with twins, their siblings and parents from 112 families. We evaluate two competing hypotheses about the cause of assortative mating in intelligence: social homogamy and phenotypic…

  1. A possible association between the genetic predisposition for dizygotic twinning and schizophrenia

    DEFF Research Database (Denmark)

    Kläning, Ulla; Pedersen, Carsten Bøcker; Mortensen, Preben Bo;

    2002-01-01

    BACKGROUND: A previous study demonstrated a 40% higher rate of schizophrenia in dizygotic twins than in the general population. The aim of the present study is to evaluate whether genes influencing the rate of dizygotic twinning and genes of importance for developing schizophrenia can be associated...... of a linkage between genes influencing the rate of dizygotic twinning and genes influencing the threshold for developing schizophrenia........ METHOD: Through record linkage between The Danish Twin Register, The Danish Psychiatric Central Register, and The Danish Civil Registration System, the rate of schizophrenia in singleton siblings of dizygotic and monozygotic twins was compared with the rate in siblings of singletons. RESULTS: The rate...

  2. Twin births

    DEFF Research Database (Denmark)

    Hoffmann, Elise; Oldenburg, Anna; Rode, Line;

    2012-01-01

    To assess morbidity and mortality in twin pregnancy deliveries, according to chorionicity and mode of delivery.......To assess morbidity and mortality in twin pregnancy deliveries, according to chorionicity and mode of delivery....

  3. What Virtual Twins Reveal About General Intelligence and Other Behaviors

    OpenAIRE

    2012-01-01

    The Fullerton Virtual Twin Study has been assessing the behaviors of an unusual sibship since 1982. Virtual twins (VTs) are same-age, unrelated siblings reared together since infancy. They replicate the rearing situation of twins but without the genetic link, enabling direct assessment of shared environmental effects on behavior. An updated analysis of IQ data, based on an increased sample of 142 VT pairs (7.87 years, SD=8.22), is presented. Intraclass correlations of .28 (IQ) and .11 (subtes...

  4. Craniofacial Skeletal Dysplasia of Opposite-sex Dizygotic Twins

    Directory of Open Access Journals (Sweden)

    Szu-Ting Chou

    2011-05-01

    Full Text Available Craniofacial skeletal dysplasia can lead to different skeletal malocclusions. Both environmental factors and heredity contribute to the formation of malocclusions. There are strong familial tendencies in the development of Angle's Class II and III malocclusions. Cases such as opposite-typed (Class II and III malocclusions with skeletal and dentoalveolar discordance in siblings or dizygotic (DZ twins have seldom been reported. We describe the rare case of a pair of opposite-sex DZ twins with completely different skeletal malocclusions, and discuss the clinical considerations for treatment. The patients were twins aged 13 years and 4 months. The girl had mandibular prognathism and a Class III dentoskeletal relationship, whereas the boy had skeletal Class II with mandibular retrusion. Several morphological traits have been implicated with hormonal effect. However, there was no evidence of whether the masculinization effect had any impact on jaw size in the female fetus or whether this effect lasted into adolescence. We suggest that, although DZ twins share the same growth environment, genetic or other unknown extrinsic factors can result in discordance of characteristics of the craniofacial skeleton, dentition, and occlusion.

  5. Personality and birth order in monozygotic twins adopted apart: a test of Sulloway's theory; Research Reviews: twin births and cancer risk in mothers, male sexual dysfunction, twin study of ultimatum game behavior; Human Interest: 'The Land of Twins', twin-like reunion-I, twin-like reunion-II.

    Science.gov (United States)

    Segal, Nancy L

    2008-02-01

    A brief overview of Sulloway's (1996) theory of birth order and personality is presented. A reared apart twin approach for testing his personality findings regarding openness to experience and conscientiousness in first borns and later borns is described. This is followed by summaries of three recent twin studies. The topics include cancer risk in mother of twins, sexual dysfunction in males and responder behavior during ultimatum games. This article concludes with a discussion of twinning rates and rituals among the Yoruba of western Nigeria, and descriptions of two unusual reunions between siblings and twins.

  6. Testing for Neuropsychological Endophenotypes in Siblings Discordant for ADHD

    Science.gov (United States)

    Bidwell, L. Cinnamon; Willcutt, Erik G.; DeFries, John C.; Pennington, Bruce F.

    2007-01-01

    Objective Neurocognitive deficits associated with attention deficit-hyperactivity disorder (ADHD) may be useful intermediate endophenotypes for determining specific genetic pathways that contribute to ADHD. Methods This study administered 17 measures from prominent neuropsychological theories of ADHD (executive function, processing speed, arousal regulation and motivation/delay aversion) in dizygotic (DZ) twin pairs discordant for ADHD and control twin pairs (ages 8–18) in order to compare performance between twins affected with ADHD (n = 266), their unaffected co-twins (n = 228), and control children from twin pairs without ADHD or learning difficulties (n = 332). Results ADHD subjects show significant impairment on executive function, processing speed, and response variability measures compared to control subjects. Unaffected cotwins of ADHD subjects are significantly impaired on nearly all the same measures as their ADHD siblings, even when subclinical symptoms of ADHD are controlled. Conclusion Executive function, processing speed, and response variability deficits may be useful endophenotypes for genetic studies of ADHD. PMID:17585884

  7. The Promoted Sibling

    DEFF Research Database (Denmark)

    Visholm, Steen

    PRESENTATION No 72 Steen Visholm Associate professor, M.Psych., Ph. D., Roskilde University Private adress: Krystalgade 6 II DK-1172 København K Denmark svisholm@ruc.dk THE PROMOTED SIBLING By their writings about sibling relations Mitchell and Coles has added fruitful complexity to the psychodyn......PRESENTATION No 72 Steen Visholm Associate professor, M.Psych., Ph. D., Roskilde University Private adress: Krystalgade 6 II DK-1172 København K Denmark svisholm@ruc.dk THE PROMOTED SIBLING By their writings about sibling relations Mitchell and Coles has added fruitful complexity...... to the psychodynamic understanding of families, groups and organisations. With a point of departure in a study of self-governing groups in a factory the paper introduces the concept: ‘the promoted sibling’ which provide quite some understanding of the middle managers challenges in his or her role and the challenges...... in democracy in general. The middle manager can be seen as ‘a sibling promoted from above’ and democracy can be seen as siblings promoting a sibling to be ‘a temporary parent’ (Winnicott) or ‘a sibling promoted from below’. The extension of the family dynamics with the sibling relations provides a way...

  8. Hemoglobin profiles of siblings of thalassemia patients

    Directory of Open Access Journals (Sweden)

    Muhammad Riza

    2015-03-01

    Full Text Available Background Thalassemia and hemoglobinopathies are the most common inherited disorders in many areas of the world, including South East Asia. The siblings of thalassemia major is a group of high risk to carry the gene of thalassemia. Determining the carrier is useful for early treatment planning and prevention to the next child. Objective To determine carrier status among siblings of thalassemia patients using a capillary electrophoresis system. Methods A cross-sectional study on the siblings of thalassemia major patients was performed from January 2011 to February 2012 at Dr. Moewardi Hospital. Complete blood counts were performed in the siblings. Subjects with mean corpuscular volume (MCV <80 fl and mean corpuscular hemoglobin (MCH <27 pg were subjected to analize hemoglobin fraction by capillary electrophoresis. Results Of the 26 subjects, there were 12 males and 14 females. The mean age was 9.38 (SD 6.8 years (range 1 to 29 years. From the siblings, 10 were identified as normal, 5 were identified as ß thalassemia carriers and 5 were hemoglobin E (HbE carriers. Six siblings were diagnosed with ß thalassemia/ HbE. Conclusion There are high occurrence of the two common types of thalassemia carriers (ß and HbE in our small group of subjects who had a family history of thalassemia. Most of the siblings of thalassemia had low MCV and MCH. [Paediatr Indones. 2015;55:70-3.].

  9. Only full-sibling families evolved eusociality

    DEFF Research Database (Denmark)

    Boomsma, Jacobus J; Beekman, Madeleine; Cornwallis, Charlie K

    2011-01-01

    Arising from M. A. Nowak, C. E. Tarnita & E. O. Wilson 466, 1057-1062 (2010); Nowak et al. reply. The paper by Nowak et al. has the evolution of eusociality as its title, but it is mostly about something else. It argues against inclusive fitness theory and offers an alternative modelling approach...

  10. The Promoted Sibling

    DEFF Research Database (Denmark)

    Visholm, Steen

    between the followers. Creativity seems to be closely linked to envy and dealing with envy and fear of envy seems to be an issue in growth. Litterature: Prophency Coles: The Importance of Sibling Relationships in Psychoanalysis. London & New York: Karnac 2003 Mitchell, Juliet (2003): Siblings. Sex...

  11. Neonatal status of twins

    Directory of Open Access Journals (Sweden)

    Božinović Dragica

    2012-01-01

    Full Text Available Multiple pregnancy is a pregnancy where more than one fetus develops simultaneously in the womb, as a result of the ovulation and fertilization of more than one egg. It is relatively rare in humans and represents the rest of the phylogenetic stages. The most common are twins and they indicate the development of two fetuses in the womb. The frequency of twin pregnancies is about 1%. Multiple pregnancies belong to a group of high-risk pregnancies because of the many complications that occur during the pregnancy: higher number of premature deliveries, bleeding, early neonatal complications and higher perinatal morbidity and mortality. Such pregnancies and infants require greater supervision and monitoring. The aim of this study was to determine the percentage of baby twins born at the maternity ward of the General Hospital in Prokuplje and their morbidity and mortality. Data on the total number of deliveries, number of twins, parity and maternal age, gestational age, body weight of twins, method of delivery, Apgar score and perinatal mortality were collected and statistically analyzed by means of retrospective analysis of operative birth and neonatal protocol for 6 years (2005 of 2010. Out of 4527 mothers who gave birth 43 were pairs of twins, or 0.95% of women gave birth to twins. These babies are more likely born by Caesarean section, but delivered with slightly lower birth weight.

  12. First-born siblings show better second language skills than later born siblings

    Directory of Open Access Journals (Sweden)

    Karin eKeller

    2015-06-01

    Full Text Available We examined the extent to which three sibling structure variables number of siblings, birth order and presence of an older sibling at school age are linked to the second language skills of bilingual children. The research questions were tested using an ethnically heterogeneous sample of 1209 bilingual children with German as a second language. Controlling for children’s age, sex, nationality, number of children’s books at home, family language and parental German language skills, hierarchical regression analyses showed an inverse relationship between the number of siblings and second language skills: The more siblings a child had, the lower was his/her second language proficiency. This relationship was mediated by attendance in early education institutions. Moreover, first-born siblings showed better second language skills than later born siblings.The current study revealed that the resource dilution model, i.e., the decrease in resources for every additional sibling, holds for second language acquisition. Moreover, the results indicate that bilingual children from families with several children benefit from access to early education institutions.

  13. Genome-wide analysis of DNA methylation, copy number variation, and gene expression in monozygotic twins discordant for primary biliary cirrhosis

    Directory of Open Access Journals (Sweden)

    Carlo eSelmi

    2014-03-01

    Full Text Available Primary biliary cirrhosis (PBC is an uncommon autoimmune disease with a homogeneous clinical phenotype that reflects incomplete disease concordance in monozygotic (MZ twins. We have taken advantage of a unique collection consisting of genomic DNA and mRNA from peripheral blood cells of female MZ twins (n=3 sets and sisters of similar age (n=8 pairs discordant for disease. We performed a genome-wide study to investigate differences in (i DNA methylation (using a custom tiled 4-plex array containing tiled 50-mers 19,084 randomly chosen methylation sites, (ii copy number variation (CNV (with a chip including markers derived from the 1000 Genomes Project, all three HapMap phases, and recently published studies, and/or (iii gene expression (by whole-genome expression arrays. Based on the results obtained from these three approaches we utilized quantitative PCR to compare the expression of candidate genes. Importantly, our data support consistent differences in discordant twins and siblings for the (i methylation profiles of 60 gene regions, (ii CNV of 10 genes, and (iii the expression of 2 interferon-dependent genes. Quantitative PCR analysis showed that 17 of these genes are differentially expressed in discordant sibling pairs. In conclusion, we report that MZ twins and sisters discordant for PBC manifest particular epigenetic differences and highlight the value of the epigenetic study of twins.

  14. Using Sibling Designs to Understand Neurodevelopmental Disorders: From Genes and Environments to Prevention Programming

    Directory of Open Access Journals (Sweden)

    Mark Wade

    2015-01-01

    Full Text Available Neurodevelopmental disorders represent a broad class of childhood neurological conditions that have a significant bearing on the wellbeing of children, families, and communities. In this review, we draw on evidence from two common and widely studied neurodevelopmental disorders—autism spectrum disorder (ASD and attention-deficit hyperactivity disorder (ADHD—to demonstrate the utility of genetically informed sibling designs in uncovering the nature and pathogenesis of these conditions. Specifically, we examine how twin, recurrence risk, and infant prospective tracking studies have contributed to our understanding of genetic and environmental liabilities towards neurodevelopmental morbidity through their impact on neurocognitive processes and structural/functional neuroanatomy. It is suggested that the siblings of children with ASD and ADHD are at risk not only of clinically elevated problems in these areas, but also of subthreshold symptoms and/or subtle impairments in various neurocognitive skills and other domains of psychosocial health. Finally, we close with a discussion on the practical relevance of sibling designs and how these might be used in the service of early screening, prevention, and intervention efforts that aim to alleviate the negative downstream consequences associated with disorders of neurodevelopment.

  15. Twin pregnancy

    DEFF Research Database (Denmark)

    Sperling, Lene; Tabor, A

    2001-01-01

    Determination of chorionicity is one of the most important issues in the management of twin pregnancy. Modern ultrasound equipment has made it possible to accurately assess placentation already in the first trimester with the lambda sign. With regard to prenatal diagnosis, it is important to know...... for clinicians caring for twin pregnancies....

  16. Twin-twin transfusion syndrome - diagnosis and prognosis

    Directory of Open Access Journals (Sweden)

    Hajrić-Egić Amira

    2003-01-01

    Full Text Available Twin-twin transfusion syndrome is a serious complication of monozygotic, monochorionic, diamniotic twins resulting from transplacental vascular communications. In this syndrome blood is thought to be shunted from one twin - donor,who develops anaemia,growth retardation and oligoamnios, to the other twin - recipient,who becomes plethoric,macrosomic and develops polyhydroamnios. The incidence of twin-twin transfusion syndrome ranges from 5-15% of all twin pregnancies. If this condition develops in the second trimester, it is usually associated with spontaneous abortion and death of one or both fetuses before viability. Developing the syndrome in the third trimester has better perinatal outcome. Mortality rates ranging from 56%-100%, depending on gestational age and severity of the syndrome. The ultrasound criterias for diagnosis, in this study,were the presence of twins of the same sex with discordant growth, with oligohydroamnios in one twin sac and polyhydroamnios in the other one, one placenta and thin membrane between twins. The present study shows clinical course of 14 cases and value of Doppler ultrasound to analyze the usefulness of umbilical artery blood flow velocimetry for predicting the risk of twin-twin transfusion syndrome. 14 twin pregnancies with twin-twin transfusion syndrome were diagnosed during the last four years period and prospectivelly followed. 9 cases were diagnosed before the completion od 28 weeks of gestation.The mean gestational age was 21,6_+4,2 weeks at diagnosis and 23,2+_3,6 weeks at delivery. 5 cases were diagnosed after 28 weeks of gestation. The mean gestational age in this group was 29,6+_2,1 weeks at diagnosis and 33+_3,3 weeks at delivery. The survival rate in this study was 29%(8/28.9 cases ended in spontaneous abortion between 18th and 27th weeks of pregnancy (table 1 and 5 in premature labor (table 2.There were 7 intrauterine death (5 at admission and 2 few days after admission and 13 neonatal deaths

  17. A registry of adult African American twins: the Carolina African American Twin Study of Aging.

    Science.gov (United States)

    Whitfield, Keith E

    2013-02-01

    Twin studies have seldom addressed ethnicity as one of the possible factors that create unique combinations of genetic and environmental influences. The major objective of the Carolina African American Twin Study of Aging is to identify the proportion of the genetic and environmental sources of individual variation in measures of health and behavioral factors in a sample of adult African Americans. Drawn from birth records from the State of North Carolina, this in-person study used public records to identify a cohort of twins between 22 and 92 years of age (X = 49.82 yrs, SD = 14.62), 39.7% of which were men. Members of non-intact twin pairs and siblings were also recruited to explore alternative models to the classic twin design. To date, the project has contributed to knowledge about blood pressure, forced expiratory volume, chronic illness, body mass index, and waist-hip ratio memory, personality, social, and demographic factors, mortality, and mental health.

  18. Genetic and environmental influences on type A behavior pattern: evidence from twins and their parents in the Netherlands Twin Register.

    Science.gov (United States)

    Rebollo, Irene; Boomsma, Dorret I

    2006-01-01

    There is a dose-response positive relationship between type A behavior (TABP) and cardiovascular disease-related symptoms. Estimates of heritability for TABP from previous studies vary; this might be explained by limitations in the sizes and compositions of the samples. This study combines a large sample size, twin and parental, data from males and females, two generations of young adults and older adults, and the use of structural equation modeling (SEM) and full information maximum likelihood (FIML) estimation. To assess TABP, the Jenkins Activity Survey (JAS) was collected from MZ and DZ twins and their parents (n = 1670 twin families). Structural equation modeling is used to evaluate and estimate the effects of additive and nonadditive genetic effects, nonshared environmental effects, and competitive sibling interaction. Forty-five percent of the variance in TABP was the result of genetic factors (28% were additive and 17% were nonadditive). The remaining 55% of the variance was explained by environmental factors not shared by the members of the same family. Competitive sibling interaction effects were not significant. There was no evidence of sex differences either in variances or means. Understanding the sources of variance on TABP is important for therapy and prevention. According to the present results, the relevant environmental factors for the development of TABP are not shared by the members of the same family. The genetic portion of the variance is also worth considering for therapeutic purposes. Although the genetic code cannot be altered, its effects on behavior may be modifiable through the treatment of the biological mediators.

  19. Siblings: thinking theory.

    Science.gov (United States)

    Mitchell, Juliet

    2013-01-01

    The paper argues for the development of a theoretical understanding of lateral relations, starting with siblings, along a horizontal axis. This would be autonomous but interactive with the vertical axis of parent-child.

  20. The genus Drosophila is characterized by a large number of sibling species showing evolutionary significance

    Indian Academy of Sciences (India)

    BASHISTH N. SINGH

    2016-12-01

    Mayr (1942) defined sibling species as sympatric forms which are morphologically very similar or indistinguishable, but which possess specific biological characteristics and are reproductively isolated. Another term, cryptic species has also been used for such species. However, this concept changed later. Sibling species are as similar as twins. This category does not necessarily include phylogenetic siblings as members of a superspecies. Since the term sibling species was defined by Mayr, a large number of cases of sibling species pairs/groups have been reported and thus they are widespread in the animal kingdom.However, they seem to be more common in some groups such as insects. In insects, they have been reported in diptera, lepidoptera, coleoptera, orthoptera, hymenoptera and others. Sibling species are widespread among the dipteran insects and as such are well studied because some species are important medically (mosquitoes), genetically (Drosophila) and cytologically(Sciara and Chironomus). The well-studied classical pairs of sibling species in Drosophila are: D. pseudoobscura and D. persimilis, and D. melanogaster and D. simulans. Subsequently, a number of sibling species have been added to these pairs and a large number of other sibling species pairs/groups in different species groups of the genus Drosophila have been reported in literature. The present review briefly summarizes the cases of sibling species pairs/groups in the genus Drosophila with their evolutionary significance.

  1. [Twin dystocia: about one case of compaction].

    Science.gov (United States)

    Desseauve, D; Voluménie, J-L

    2008-09-01

    We report a case of twin dystocia during the evacuation of full-term fetus both in cephalic presentation. A low-outlet forceps for second-phase arrest was performed for the first twin but the head remained stuck to maternal perineum, mimicking a shoulder dystocia. Digital examination found a twin compaction, that is the presence of the second twin's fetal head at the level of the first twin's chest. The discrepancy between fetal weights and the use of forceps could favor this rare complication. Various maneuvers were described previously attempted to solve the problem. Forcing back the second head may help to achieve delivery of the first twin.

  2. The Glass is Half Full and Half Empty: A population-representative twin study testing if Optimism and Pessimism are distinct systems

    Science.gov (United States)

    Bates, Timothy C.

    2015-01-01

    Optimism and pessimism are associated with important outcomes including health and depression. Yet it is unclear if these apparent polar opposites form a single dimension or reflect two distinct systems. The extent to which personality accounts for differences in optimism/pessimism is also controversial. Here, we addressed these questions in a genetically informative sample of 852 pairs of twins. Distinct genetic influences on optimism and pessimism were found. Significant family-level environment effects also emerged, accounting for much of the negative relationship between optimism and pessimism, as well as a link to neuroticism. A general positive genetics factor exerted significant links among both personality and life-orientation traits. Both optimism bias and pessimism also showed genetic variance distinct from all effects of personality, and from each other. PMID:26561494

  3. [Hereditary phaeochromocytoma in twins].

    Science.gov (United States)

    Tóth, Géza; Patócs, Attila; Tóth, Miklós

    2016-08-01

    Phaeochromocytoma is a tumor of the catecholamine-producing cells of the adrenal gland. Extraadrenal phaeochromocytomas are frequently called paragangliomas. The majority of phaeochromocytomas are sporadic, however, about 25-30% are caused by genetic mutation. These tumor are frequently referred as hereditary phaeochromocytomas/paragangliomas. Their incidence increases continuously which can be attributed to availability of genetic examination and to the discovery of novel genes. The 47-year-old female patient underwent abdominal computed tomography which revealed bilateral adrenal gland enlargement. Abdominal magnetic resonance imaging, the 131-I- metaiodobenzylguanidine scintigraphy, urinary catecholamines and serum chomogranin A measurements confirmed the diagnosis of bilateral phaeochromocytomas. The genetically identical twin sister of the patient was also diagnosed with hormonally active bilateral phaechromocytoma, suggesting the genetic origin of phaeochromocytoma. Mutation screening confirmed a germline mutation of the transmembrane protein 127 tumorsupressor gene in both patients. Both patients underwent cortical-sparing adrenalectomy. The adrenal gland with the larger tumor was totally resected, while in the opposite side only the tumor was resected and a small part of the cortex was saved. After the operation urinary catecholamines and serum chromogranin A returned to normal in both patients. Adrenocortical deficiency was absent in the first patient, but her sister developed adrenal insufficiency requiring glucocorticoid replacement. To the best of the authors' knowledge phaeochromocytoma affecting twins has never been described earlier. Genetic examination performed in siblings confirmed the presence of the mutant gene through four generations. Orv. Hetil., 2016, 157(33), 1326-1330.

  4. Virtual Twins: New Findings on Within-Family Environmental Influences on Intelligence.

    Science.gov (United States)

    Segal, Nancy L.

    2000-01-01

    Virtual twins are unrelated siblings of the same age who are reared together from early infancy (UST-SA). Study uses a sample of 90 UST-SA pairs to comparatively assess the similarity of IQ subtest profile correlations for UST-SAs and twin pairs. Findings support explanatory models of intelligence that include genetic factors, demonstrating that…

  5. Cortical Excitability Measures in Patients and Unaffected Siblings

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2013-05-01

    Full Text Available Researchers at St Vincent's Hospital, Victoria, Australia, measured cortical excitability using transcranial magnetic stimulation in 157 patients with epilepsy (95 generalized and 62 focal and their asymptomatic siblings and results were compared to those of 12 controls and 20 of their siblings.

  6. Testing for neuropsychological endophenotypes in siblings discordant for attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Bidwell, L Cinnamon; Willcutt, Erik G; Defries, John C; Pennington, Bruce F

    2007-11-01

    Neurocognitive deficits associated with attention-deficit/hyperactivity disorder (ADHD) might be useful intermediate endophenotypes for determining specific genetic pathways that contribute to ADHD. This study administered 17 measures from prominent neuropsychological theories of ADHD (executive function, processing speed, arousal regulation and, motivation/delay aversion) in dizygotic (DZ) twin pairs discordant for ADHD and control twin pairs (ages 8-18 years) to compare performance between twins affected with ADHD (n = 266), their unaffected co-twins (n = 228), and control children from twin pairs without ADHD or learning difficulties (n = 332). The ADHD subjects show significant impairment on executive function, processing speed, and response variability measures compared with control subjects. Unaffected co-twins of ADHD subjects are significantly impaired on nearly all the same measures as their ADHD siblings, even when subclinical symptoms of ADHD are controlled. Executive function, processing speed, and response variability deficits might be useful endophenotypes for genetic studies of ADHD.

  7. B-Lymphocytes from a Population of Children with Autism Spectrum Disorder and Their Unaffected Siblings Exhibit Hypersensitivity to Thimerosal

    Directory of Open Access Journals (Sweden)

    Martyn A. Sharpe

    2013-01-01

    Full Text Available The role of thimerosal containing vaccines in the development of autism spectrum disorder (ASD has been an area of intense debate, as has the presence of mercury dental amalgams and fish ingestion by pregnant mothers. We studied the effects of thimerosal on cell proliferation and mitochondrial function from B-lymphocytes taken from individuals with autism, their nonautistic twins, and their nontwin siblings. Eleven families were examined and compared to matched controls. B-cells were grown with increasing levels of thimerosal, and various assays (LDH, XTT, DCFH, etc. were performed to examine the effects on cellular proliferation and mitochondrial function. A subpopulation of eight individuals (4 ASD, 2 twins, and 2 siblings from four of the families showed thimerosal hypersensitivity, whereas none of the control individuals displayed this response. The thimerosal concentration required to inhibit cell proliferation in these individuals was only 40% of controls. Cells hypersensitive to thimerosal also had higher levels of oxidative stress markers, protein carbonyls, and oxidant generation. This suggests certain individuals with a mild mitochondrial defect may be highly susceptible to mitochondrial specific toxins like the vaccine preservative thimerosal.

  8. Twin Baryogenesis

    CERN Document Server

    Farina, Marco; Shin, Chang Sub

    2016-01-01

    In the context of Twin Higgs models, we study a simple mechanism that simultaneously generates asymmetries in the dark and visible sector through the out-of-equilibrium decay of a TeV scale particle charged under a combination of baryon and twin baryon number. We predict the dark matter to be a 5 GeV twin baryon, which is easy to achieve because of the similarity between the two confinement scales. Dark matter is metastable and can decay to three quarks, yielding indirect detection signatures. The mechanism requires the introduction of a new colored particle, typically within the reach of the LHC, of which we study the rich collider phenomenology, including prompt and displaced dijets, multi-jets, monojets and monotops.

  9. Sleep Terrors in Twins

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2008-12-01

    Full Text Available In an attempt to clarify the genetic and environmental causes of sleep terrors in childhood, reasearchers in Canada followed 390 pairs of monozygotic and dizygotic twins by assessing the frequency of sleep terrors at 18 and 30 months of age using a questionnaire administered to the biological mothers.

  10. Amelia in Twin Pregnancy

    Directory of Open Access Journals (Sweden)

    Davari Tanha Fatemeh

    2009-04-01

    Full Text Available Limb bud first appears during the third week of gestation with the upper limb buds appearing a few days before the lower limb buds. Complete absence of one or more limbs, called Amelia, occurs prior to the eighth week of gestation. We report a case of Amelia in a twin gestation.

  11. Twinning across the Developing World.

    Directory of Open Access Journals (Sweden)

    Jeroen Smits

    Full Text Available BACKGROUND: Until now, little was known about the variation in incidence of twin births across developing countries, because national representative data was lacking. This study provides the first comprehensive overview of national twinning rates across the developing world on the basis of reliable survey data. METHODS: Data on incidence of twinning was extracted from birth histories of women aged 15-49 interviewed in 150 Demographic and Health Surveys, held between 1987 and 2010 in 75 low and middle income countries. During the interview, information on all live births experienced by the women was recorded, including whether it was a singleton or multiple birth. Information was available for 2.47 million births experienced by 1.38 million women in a period of ten years before the interview. Twinning incidence was measured as the number of twin births per thousand births. Data for China were computed on the basis of published figures from the 1990 census. Both natural and age-standardized twinning rates are presented. RESULTS/CONCLUSIONS: The very low natural twinning rates of 6-9 per thousand births previously observed in some East Asian countries turn out to be the dominant pattern in the whole South and South-East Asian region. Very high twinning rates of above 18 per thousand are not restricted to Nigeria (until now seen as the world's twinning champion but found in most Central-African countries. Twinning rates in Latin America turn out to be as low as those in Asia. Changes over time are small and not in a specific direction. SIGNIFICANCE: We provide the most complete and comparable overview of twinning rates across the developing world currently possible.

  12. Development of the preterm gut microbiome in twins at risk of necrotising enterocolitis and sepsis.

    Directory of Open Access Journals (Sweden)

    Christopher J Stewart

    Full Text Available The preterm gut microbiome is a complex dynamic community influenced by genetic and environmental factors and is implicated in the pathogenesis of necrotising enterocolitis (NEC and sepsis. We aimed to explore the longitudinal development of the gut microbiome in preterm twins to determine how shared environmental and genetic factors may influence temporal changes and compared this to the expressed breast milk (EBM microbiome. Stool samples (n = 173 from 27 infants (12 twin pairs and 1 triplet set and EBM (n = 18 from 4 mothers were collected longitudinally. All samples underwent PCR-DGGE (denaturing gradient gel electrophoresis analysis and a selected subset underwent 454 pyrosequencing. Stool and EBM shared a core microbiome dominated by Enterobacteriaceae, Enterococcaceae, and Staphylococcaceae. The gut microbiome showed greater similarity between siblings compared to unrelated individuals. Pyrosequencing revealed a reduction in diversity and increasing dominance of Escherichia sp. preceding NEC that was not observed in the healthy twin. Antibiotic treatment had a substantial effect on the gut microbiome, reducing Escherichia sp. and increasing other Enterobacteriaceae. This study demonstrates related preterm twins share similar gut microbiome development, even within the complex environment of neonatal intensive care. This is likely a result of shared genetic and immunomodulatory factors as well as exposure to the same maternal microbiome during birth, skin contact and exposure to EBM. Environmental factors including antibiotic exposure and feeding are additional significant determinants of community structure, regardless of host genetics.

  13. Monomelic amyotrophy in siblings.

    Science.gov (United States)

    Gücüyener, K; Aysun, S; Topaloglu, H; Inan, L; Varli, K

    1991-01-01

    Monomelic amyotrophy is a rare, benign motor neuron disorder. Electrophysiologic studies are suggestive of localized chronic anterior horn cell disease. Two young siblings are reported with monomelic amyotrophy who had proximal muscle weakness confined to one arm. We propose that monomelic amyotrophy, at least in this family, is inherited as an autosomal recessive trait.

  14. Progeria in siblings: A rare case report

    Directory of Open Access Journals (Sweden)

    R Sowmiya

    2011-01-01

    Full Text Available Progeria, also known as Hutchinson-Gilford syndrome, is an extremely rare, severe genetic condition wherein symptoms resembling aspects of aging are manifested at an early age. It is an autosomal dominant disorder. It is not seen in siblings of affected children although there are very few case reports of progeria affecting more than one child in a family. Here we are presenting two siblings, a 14-year-old male and a 13-year-old female with features of progeria, suggesting a possible autosomal recessive inheritance.

  15. Twin-singleton differences in intelligence: a register-based birth cohort study of Norwegian males.

    Science.gov (United States)

    Eriksen, Willy; Sundet, Jon M; Tambs, Kristian

    2012-10-01

    The aim was to determine the difference in intelligence between singletons and twins in young adulthood. Data from the Medical Birth Register of Norway were linked with register data from the Norwegian National Conscript Service. The study base consisted of data on the 445,463 males who were born alive in either single or twin births in Norway during 1967-1984 and who were examined at the time of the mandatory military conscription (age 18-20). Within this study base, there were data on 1,653 sibships of full brothers that included at least one man born in single birth and at least one man born in twin birth (4,307 persons, including 2,378 twins and 1,929 singletons). The intelligence scores of the singletons were 11% (95% confidence interval [CI]: 9-14%) of a standard deviation higher than those of the twins, after adjustment for birth year, birth order, parental ages at delivery, parental education levels, and other factors. The adjusted within-family difference was also 11% (95 % CI: 6-16%) of a standard deviation, indicating that unmeasured factors shared by siblings (e.g., maternal body height) have not influenced the estimate in important ways. When gestational age at birth was added to the model, the estimate for the difference in intelligence score was approximately the same. Including birth weight in the model strongly reduced the estimate. In conclusion, twins born in Norway during 1967-1984 had slightly lower intelligence in early adulthood compared with the singletons.

  16. Simultaneous Intussusception in Monozygotic Twins

    Directory of Open Access Journals (Sweden)

    Mete Kaya

    2014-12-01

    Full Text Available In this case report, it was aimed to present the simultaneously occurring intussusception in the monozygotic twins. In addition to genetic predisposition, environmental factors has been hypothesized to be responsible for the development of the disease.

  17. Fraser syndrome in three consecutive siblings

    Directory of Open Access Journals (Sweden)

    Kaarthigeyan Kalaniti

    2011-01-01

    Full Text Available Fraser syndrome (FS is a rare disorder characterized by a combination of acrofacial and urogenital malformations with or without cryptophthalmos. We report a newborn and its two elder siblings who had multiple congenital anomalies and clinico-radiological features consistent with FS.

  18. Two Siblings Diagnosed as Lafora Disease

    Directory of Open Access Journals (Sweden)

    Yasemin Biçer Gömceli

    2010-03-01

    Full Text Available Lafora disease is a typical progressive myoclonic epilepsy that is characterized by autosomal recessive inheritance, myoclonic and occipital seizures, progressive dementia, ataxia, and dysarthria. Two siblings with myoclonic and generalized tonic clonic seizures, progressive dementia, ataxia and dysarthria, who were diagnosed as Lafora disease by sweat gland biopsy, are discussed.

  19. Sibling influences on prosocial behavior.

    Science.gov (United States)

    Hughes, Claire; McHarg, Gabrielle; White, Naomi

    2017-08-12

    Sibling relationships are characterized by familiarity and emotional intensity. Alongside frequent shared play, sibling interactions feature complementary interactions (e.g. teaching, caregiving) reflecting age-related asymmetries in socio-cognitive skills. These aspects may underpin sibling influences on prosocial behavior: theoretical accounts of social influences on prosocial behavior highlight emotion sharing, goal alignment, the intrinsically rewarding nature of social interaction, and scaffolding of social norms. Taking a fine-grained approach to prosocial behavior, we examine these processes in relation to sibling influences on children's comforting, sharing, and helping. Emergent themes include: developmental change in the nature of sibling influences on prosocial behavior, the need to consider sibling influences in the wider family context, and the importance of individual differences in the quality of sibling relationships. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Aggression can be contagious: Longitudinal associations between proactive aggression and reactive aggression among young twins.

    Science.gov (United States)

    Dickson, Daniel J; Richmond, Ashley D; Brendgen, Mara; Vitaro, Frank; Laursen, Brett; Dionne, Ginette; Boivin, Michel

    2015-01-01

    The present study examined sibling influence over reactive and proactive aggression in a sample of 452 same-sex twins (113 male dyads, 113 female dyads). Between and within siblings influence processes were examined as a function of relative levels of parental coercion and hostility to test the hypothesis that aggression contagion between twins occurs only among dyads who experience parental coerciveness. Teacher reports of reactive and proactive aggression were collected for each twin in kindergarten (M = 6.04 years; SD = 0.27) and in first grade (M = 7.08 years; SD = 0.27). Families were divided into relatively low, average, and relatively high parental coercion-hostility groups on the basis of maternal reports collected when the children were 5 years old. In families with relatively high levels of parental coercion-hostility, there was evidence of between-sibling influence, such that one twin's reactive aggression at age 6 predicted increases in the other twin's reactive aggression from ages 6 to 7, and one twin's proactive aggression at age 6 predicted increases in the other twin's proactive aggression from ages 6 to 7. There was also evidence of within-sibling influence such that a child's level of reactive aggression at age 6 predicted increases in the same child's proactive aggression at age 7, regardless of parental coercion-hostility. The findings provide new information about the etiology of reactive and proactive aggression and individual differences in their developmental interplay.

  1. TWIN BLOCK (Studi Pustaka

    Directory of Open Access Journals (Sweden)

    Evie Lamtiur

    2015-08-01

    Full Text Available Young patients with class II skeletal malocclusion are often found. To avoid further discrepancy of this case, myofunctional therapy is one of the options. Functional appliance often used for such treatment. Functional appliance has been modified since activator was introduced by Andresen. With its bulky shape, activator makes difficulty for patient to speak and eat. Patient unable to wear it full time due to uncomfortness and negative facial appearance. In 1977, Clark developed twin block to overcome the weakness of previous appliances. A more simple design allows patient to be more comfortable and willing to wear it longer. Twin block is myofunctional appliance to reposition the mandible forward for skeletal class II correction with retruded mandible. This paper describes the design, clinical management effects of twin block treatment and brief case presentation using twin block appliance. Similar to the study reports found, this case revealed improvement of facial appearance, decrease overjet and overbite, improvement of molar relationship and good compliance of patient.

  2. Acardiac Parabiotic Fetus: A Rare Complication of Twin Pregnancy

    Directory of Open Access Journals (Sweden)

    Sood S

    2015-10-01

    Full Text Available Acardiac parabiotic fetus is sequelae of complication of monochorionic monoamniotic twin pregnancy also known as Twin Reversed Arterial Perfusion Sequence (TRAP. It is rare affecting 1 in 35,000 births and 1 % of monozygotic twins. Acardiac parabiotic twin commonly known as parasite occurs rarely and may lead to high output cardiac failure, hydrops or premature delivery in the pump fetus. In this report, we present a 23 years old primigravida with twin pregnancy, with twin reversed arterial perfusion sequence with one of the twins being acardiac anceps and the other normal pump fetus. This association is relatively uncommon and therefore rarely documented.

  3. Probabilities for Solar Siblings

    Science.gov (United States)

    Valtonen, Mauri; Bajkova, A. T.; Bobylev, V. V.; Mylläri, A.

    2015-02-01

    We have shown previously (Bobylev et al. Astron Lett 37:550-562, 2011) that some of the stars in the solar neighborhood today may have originated in the same star cluster as the Sun, and could thus be called Solar Siblings. In this work we investigate the sensitivity of this result to galactic models and to parameters of these models, and also extend the sample of orbits. There are a number of good candidates for the sibling category, but due to the long period of orbit evolution since the break-up of the birth cluster of the Sun, one can only attach probabilities of membership. We find that up to 10 % (but more likely around 1 %) of the members of the Sun's birth cluster could be still found within 100 pc from the Sun today.

  4. Probabilities for Solar Siblings

    CERN Document Server

    Valtonen, M; Bobylev, V V; Myllari, A

    2015-01-01

    We have shown previously (Bobylev et al 2011) that some of the stars in the Solar neighborhood today may have originated in the same star cluster as the Sun, and could thus be called Solar Siblings. In this work we investigate the sensitivity of this result to Galactic models and to parameters of these models, and also extend the sample of orbits. There are a number of good candidates for the Sibling category, but due to the long period of orbit evolution since the break-up of the birth cluster of the Sun, one can only attach probabilities of membership. We find that up to 10% (but more likely around 1 %) of the members of the Sun's birth cluster could be still found within 100 pc from the Sun today.

  5. TRAP Sequence - An Interesting Entity in Twins

    Directory of Open Access Journals (Sweden)

    R H Srinivas Prasad

    2012-01-01

    Full Text Available Twin reversed arterial perfusion (TRAP sequence, is a rare malformation occurring in monozygotic multiple gestations. One well-developed normal (pump twin and the other twin with absent cardiac structure (acardiac, who is hemodynamically dependent on the normal (pump twin are characteristic of this syndrome. The acardiac twin develops multiple anomalies that make survival difficult. The prognosis of the pump twin is variable with mortality rate ranging from 50% to 70%. Complications that affect the prognosis of the pump twin include complications of congestive cardiac failure due to increased cardiac demand, prematurity secondary to preterm delivery, and polyhydramnios. Because of these complications prompt detection, follow-up, and treatment of this condition is very important. We report two cases of TRAP sequence that emphasizes the importance of gray-scale and color Doppler imaging in diagnosis, detection of poor prognostic features, follow-up, and management of TRAP sequence.

  6. Do Twin Boundaries Always Strengthen Metal Nanowires?

    Directory of Open Access Journals (Sweden)

    Zhang Yongfeng

    2008-01-01

    Full Text Available Abstract It has been widely reported that twin boundaries strengthen nanowires regardless of their morphology—that is, the strength of nanowires goes up as twin spacing goes down. This article shows that twin boundaries do not always strengthen nanowires. Using classical molecular dynamics simulations, the authors show that whether twin boundaries strengthen nanowires depends on the necessary stress for dislocation nucleation, which in turn depends on surface morphologies. When nanowires are circular cylindrical, the necessary stress of dislocation nucleation is high and the presence of twin boundaries lowers this stress; twin boundaries soften nanowires. In contrast, when nanowires are square cylindrical, the necessary stress of dislocation nucleation is low, and a higher stress is required for dislocations to penetrate twin boundaries; they strengthen nanowires.

  7. Emergency separation of a xipho-omphalopagus twin in a developing country

    Directory of Open Access Journals (Sweden)

    Shukla R

    2010-01-01

    Full Text Available Female conjoined twins (thoraco-omphalopagus were delivered by emergency caesarean section in a private nursing home. On examination, one of the twins was dead and was threatening the survival of the surviving twin (twin A. An emergency separation was performed to salvage the surviving twin.

  8. Conflict Resolution between Mexican Origin Adolescent Siblings

    Science.gov (United States)

    Killoren, Sarah E.; Thayer, Shawna M.; Updegraff, Kimberly A.

    2008-01-01

    We investigated correlates of adolescents' sibling conflict resolution strategies in 246, two-parent Mexican origin families. Specifically, we examined links between siblings' conflict resolution strategies and sibling dyad characteristics, siblings' cultural orientations and values, and sibling relationship qualities. Data were gathered during…

  9. Inspection Time and Cognitive Abilities in Twins Aged 7 to 17 Years: Age-Related Changes, Heritability and Genetic Covariance

    Science.gov (United States)

    Edmonds, Caroline J.; Isaacs, Elizabeth B.; Visscher, Peter M.; Rogers, Mary; Lanigan, Julie; Singhal, Atul; Lucas, Alan; Gringras, Paul; Denton, Jane; Deary, Ian J.

    2008-01-01

    We studied the age-related differences in inspection time and multiple cognitive domains in a group of monozygotic (MZ) and dizygotic (DZ) twins aged 7 to 17 years. Data from 111 twin pairs and 19 singleton siblings were included. We found clear age-related trends towards more efficient visual information processing in older participants. There…

  10. Comparison of Naturally Conceived and IVF-DZ Twins in the Netherlands Twin Registry: A Developmental Study

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    Catharina E. M. van Beijsterveldt

    2011-01-01

    Full Text Available In a large set of twin pairs, we compared twins born after IVF to naturally conceived twins with respect to birth characteristics, growth, attainment of motor milestones, and emotional and behavioral problems. Twin families were registered with the Netherlands Twin Register. We included 1534 dizygotic (DZ twins born after IVF, 5315 naturally conceived (NC DZ twins, and 1504 control NC DZ twins who were matched to the IVF twins based on maternal age, maternal educational level, smoking during pregnancy, gestational age, and offspring sex. Data were obtained by longitudinal surveys sent to fathers, mothers, and teachers at ages 1, 2, 3, 7, 10, and 12 years. Results showed no differences in growth, in attainment of motor milestones, and in behavioral development between IVF and matched NC twins. It can be concluded that for nearly all aspects, development in IVF and NC children is similar.

  11. Parent, sibling and peer influences on smoking initiation, regular smoking and nicotine dependence. Results from a genetically informative design.

    Science.gov (United States)

    Scherrer, Jeffrey F; Xian, Hong; Pan, Hui; Pergadia, Michele L; Madden, Pamela A F; Grant, Julia D; Sartor, Carolyn E; Haber, Jon Randolph; Jacob, Theodore; Bucholz, Kathleen K

    2012-03-01

    We sought to determine whether parenting, sibling and peer influences are associated with offspring ever smoking, regular smoking and nicotine dependence (ND) after controlling for familial factors. We used a twin-family design and data from structured diagnostic surveys of 1919 biological offspring (ages 12-32 years), 1107 twin fathers, and 1023 mothers. Offspring were classified into one of four familial risk groups based on twin fathers' and their co-twins' history of DSM-III-R nicotine dependence. Multivariate multinomial logistic regression was used to model familial risk, paternal and maternal parenting behavior and substance use, sibling substance use, and friend and school peer smoking, alcohol and drug use. Ever smoking was associated with increasing offspring age, white race, high maternal pressure to succeed in school, sibling drug use, and friend smoking, alcohol and drug use. Offspring regular smoking was associated with these same factors with additional contribution from maternal ND. Offspring ND was associated with increasing offspring age, male gender, biological parents divorce, high genetic risk from father and mother ND, maternal problem drinking, maternal rule inconsistency and sibling drug use, and friend smoking, alcohol and drug use. Friend smoking had the largest magnitude of association with offspring smoking. This effect remains after accounting for familial liability and numerous parent and sibling level effects. Smoking interventions may have greatest impact by targeting smoking prevention among peer groups in adolescent and young adult populations.

  12. Siblings and Adolescent Weapon Carrying: Contributions of Genetics, Shared Environment, and Nonshared Environment.

    Science.gov (United States)

    Wallace, Lacey N

    2017-07-01

    Many past studies have observed evidence of sibling similarity and influence for delinquency and substance use. However, studies of sibling similarity for adolescent weapon carrying, particularly for weapons beyond firearms, are largely absent from the literature. The present study assesses sibling similarity in weapon carrying as well as the relative contributions of genetics, shared environment, and nonshared environment. Data are obtained from the first two waves of the National Longitudinal Study of Adolescent to Adult Health and analyzed using biometrical genetic models for twins and actor-partner interdependence models for nontwins. Results indicate little, if any, contribution stemming from genetics. There is also no evidence of a significant shared environment effect. Instead, all or nearly all of the variation and similarity in weapon carrying among siblings are related to the nonshared environment, particularly gang affiliation. Implications and possible extensions of these findings are discussed.

  13. Identification of aeroelastic forces and static drag coefficients of a twin cable bridge stay from full-scale ambient vibration measurements

    DEFF Research Database (Denmark)

    Acampora, Antonio; Georgakis, Christos T.; Macdonald, J.H.G.

    2014-01-01

    Despite much research in recent years, large amplitude vibrations of inclined cables continue to be of concern for cable-stayed bridges. Various excitation mechanisms have been suggested, including rain-wind excitation, dry inclined cable galloping, high reduced velocity vortex shedding...... rather than reduced velocity, indicating that Reynolds number governs the aeroelastic effects in these conditions. There is a significant drop in the aerodynamic damping in the critical Reynolds number range, which is believed to be related to the large amplitude cable vibrations observed on some bridges...... and excitation from the deck and/or towers. Although there have been many observations of large cable vibrations on bridges, there are relatively few cases of direct full-scale cable vibration and wind measurements, and most research has been based on wind tunnel tests and theoretical modelling.This paper...

  14. Gratitude for Help among Adult Friends and Siblings

    Directory of Open Access Journals (Sweden)

    Anna Rotkirch

    2014-10-01

    Full Text Available Although gratitude is a key prosocial emotion reinforcing reciprocal altruism, it has been largely ignored in the empirical literature. We examined feelings of gratitude and the importance of reciprocity in same-sex peer relations. Participants were 772 individuals (189 men; mean age = 28.80 who completed an online survey using a vignette design. We investigated (i differences in reported gratitude and the importance of reciprocity among same-sex siblings and same-sex friends, and (ii how relationship closeness moderates these associations. Based on the theory of kin altruism, we expect that people would feel more grateful towards friends than towards their siblings, and that lack of gratitude or failure to pay back a loan would bother more with friends than with siblings, irrespective of emotional closeness. Results showed that levels of gratitude and expectations of reciprocity were higher towards friends compared to siblings. This was the case also after controlling for emotional closeness. Being close generally made participants feel more grateful and expect lower displays of gratitude in the other. Closeness was also strongly associated with emotional gratitude among siblings compared to friends. We conclude that feelings and displays of gratitude have a special role in friendships. Although a close sibling may elicit as much gratitude as a friend does, even a very close friend is not exempt from the logic of reciprocity in the same way that a sibling is.

  15. Alcohol-related morbidity and mortality within siblings

    DEFF Research Database (Denmark)

    Søndergaard, Grethe; Osler, Merete; Andersen, Anne-Marie Nybo;

    2015-01-01

    AIMS: To estimate the association between educational status and alcohol-related somatic and non-somatic morbidity and mortality among full siblings in comparison with non-related individuals. DESIGN: Cohort study. SETTING: Denmark. PARTICIPANTS: Approximately 1.4 million full siblings born......-related individuals and inter-sibling analyses were compared. FINDINGS: A lower educational status was associated with a higher rate of alcohol-related outcomes, especially among the youngest (aged 28-37 years) and individuals born 1970-79. Compared with the cohort analyses, the associations attenuated slightly...... in the inter-sibling analysis. For example, in the cohort analysis, females with a basic school education born 1970-79 had an increased rate of alcohol-related non-somatic morbidity and mortality [hazard rate ratio (HR) = 4.05, 95% confidence interval (CI) = 3.27-5.02] compared to those with a vocational...

  16. Anaesthesia for the separation of conjoined twins

    Directory of Open Access Journals (Sweden)

    Jaya Lalwani

    2011-01-01

    Full Text Available Thoraco-omphalopagus is one of the most common type of conjoint twins accounting for 74% cases of conjoint twins. We report the anaesthetic management for successful separation of thoraco-omphalopagus conjoint twins, both of them surviving till date. We highlight the responsibility of anaesthesia team in anaesthetising the two individual patients simultaneously, need of careful monitoring and anticipation of complications like massive blood loss, hypotension, hypokalemia, hypoxia and hypercabia. Detailed description of successful management is reported.

  17. Sibling Status Effects: Adult Expectations.

    Science.gov (United States)

    Baskett, Linda Musun

    1985-01-01

    This study attempted to determine what expectations or beliefs adults might hold about a child based on his or her sibling status alone. Ratings on 50 adjective pairs for each of three sibling status types, only, oldest, and youngest child, were assessed in relation to adult expectations, birth order, and parental status of rater. (Author/DST)

  18. Cancer risk in siblings of children with congenital malformations

    DEFF Research Database (Denmark)

    Sun, Yuelian; Wu, Chunsen; Arah, Onyebuchi A

    2016-01-01

    with a CM using a Cox proportional hazards regression model. To control for confounding related to change of family structure, we estimated cancer risks for children from core families and children from broken families separately. Children were followed from birth up to 30 years of age (median follow-up 13...... but had a full or half sibling with a congenital malformation (CM) diagnosed in the first year of life; this constituted the exposed group, while children whose siblings had no such condition constituted a reference group. We estimated cancer risks for children who had a full sibling or a half sibling...... a full sibling with a CM in the nervous system (HR=2.61, 95%CI:1.60-4.27) or in the eye, ear, face, or neck (HR=2.47, 95%CI: 1.46-4.18). Children who had a half sibling with a CM seemed to have a higher cancer risk in early adulthood (HR=1.87, 95%CI: 0.98-3.56). CONCLUSIONS: Children who had a full...

  19. Multiple Unerupted Teeth with Amelogenesis Imperfecta in Siblings

    Directory of Open Access Journals (Sweden)

    Shruthi Hegde

    2012-01-01

    Full Text Available Amelogenesis imperfecta encompasses a group of inherited abnormalities that are generally considered to primarily affect the formation and/or calcification of enamel. This case report describes the unusual presentation of amelogenesis imperfecta in siblings as multiple unerupted teeth, multiple pulpal calcifications, and multiple dilacerations of roots along with the defect in the enamel. The intent of our report is to highlight a rare co-occurrence of amelogenesis imperfecta with multiple morphologic alterations in siblings.

  20. Number of siblings and allergic rhinitis in children

    Directory of Open Access Journals (Sweden)

    Soewira Sastra

    2016-05-01

    Full Text Available Background Allergic rhinitis is one of the most common chronic diseases of childhood. Recent studies have suggested that having fewer siblings was associated with allergic rhinitis and atopic diseases in children. Previous studies also indicated that older siblings was associated with higher incidence of allergic rhinitis.Objectives To assess for a possible association between number of siblings and allergic rhinitis and to assess for an effect of birth order on allergic rhinitis in children.Methods We performed a cross-sectional study among school children aged 7 to 15 years, in the West Medan District from July to August 2011. Children with moderate or high risk of allergy were included. Subjects were divided into two groups, those with <3 siblings or ≥3 siblings. Children with acute respiratory tract infections, septal deviation, choanal atresia, nasal polyps, nasal tumors, or nasal foreign body were excluded. Risk of allergy was determined using the Indonesian Pediatrics Allergy Immunology Working Group trace card scoring system. Identification of allergic rhinitis and evaluation of its severity were done by use of the International Study of Asthma and Allergies in Childhood (ISAAC core questionnaire. Allergic rhinitis was diagnosed based on history, physical examination, and anterior rhinoscopy.Results A total of 78 subjects were enrolled. Allergic rhinitis was significantly higher in children with <3 siblings than those with ≥3 siblings (OR 10.33; 95%CI 3.569 to 29.916. Furthermore, allergic rhinitis was significantly higher in first-born children than in their younger siblings (P=0.0001.Conclusion Larger number of siblings and non-first-born children are associated with lower incidence of allergic rhinitis in children.

  1. Number of siblings and allergic rhinitis in children

    Directory of Open Access Journals (Sweden)

    Soewira Sastra

    2016-01-01

    Full Text Available Background Allergic rhinitis is one of the most common chronic diseases of childhood. Recent studies have suggested that having fewer siblings was associated with allergic rhinitis and atopic diseases in children. Previous studies also indicated that older siblings was associated with higher incidence of allergic rhinitis. Objectives To assess for a possible association between number of siblings and allergic rhinitis and to assess for an effect of birth order on allergic rhinitis in children. Methods We performed a cross-sectional study among school children aged 7 to 15 years, in the West Medan District from July to August 2011. Children with moderate or high risk of allergy were included. Subjects were divided into two groups, those with <3 siblings or ≥3 siblings. Children with acute respiratory tract infections, septal deviation, choanal atresia, nasal polyps, nasal tumors, or nasal foreign body were excluded. Risk of allergy was determined using the Indonesian Pediatrics Allergy Immunology Working Group trace card scoring system. Identification of aller-allergic rhinitis and evaluation of its severity were done by use of the International Study of Asthma and Allergies in Childhood (ISAAC core questionnaire. Allergic rhinitis was diagnosed based on history, physical examination, and anterior rhinoscopy. Results A total of 78 subjects were enrolled. Allergic rhinitis was significantly higher in children with <3 siblings than those with ≥3 siblings (OR 10.33; 95%CI 3.569 to 29.916. Furthermore, allergic rhinitis was significantly higher in first-born children than in their younger siblings (P=0.0001. Conclusion Larger number of siblings and non-first-born children are associated with lower incidence of allergic rhinitis in children.

  2. Fingerprint recognition with identical twin fingerprints.

    Directory of Open Access Journals (Sweden)

    Xunqiang Tao

    Full Text Available Fingerprint recognition with identical twins is a challenging task due to the closest genetics-based relationship existing in the identical twins. Several pioneers have analyzed the similarity between twins' fingerprints. In this work we continue to investigate the topic of the similarity of identical twin fingerprints. Our study was tested based on a large identical twin fingerprint database that contains 83 twin pairs, 4 fingers per individual and six impressions per finger: 3984 (83*2*4*6 images. Compared to the previous work, our contributions are summarized as follows: (1 Two state-of-the-art fingerprint identification methods: P071 and VeriFinger 6.1 were used, rather than one fingerprint identification method in previous studies. (2 Six impressions per finger were captured, rather than just one impression, which makes the genuine distribution of matching scores more realistic. (3 A larger sample (83 pairs was collected. (4 A novel statistical analysis, which aims at showing the probability distribution of the fingerprint types for the corresponding fingers of identical twins which have same fingerprint type, has been conducted. (5 A novel analysis, which aims at showing which finger from identical twins has higher probability of having same fingerprint type, has been conducted. Our results showed that: (a A state-of-the-art automatic fingerprint verification system can distinguish identical twins without drastic degradation in performance. (b The chance that the fingerprints have the same type from identical twins is 0.7440, comparing to 0.3215 from non-identical twins. (c For the corresponding fingers of identical twins which have same fingerprint type, the probability distribution of five major fingerprint types is similar to the probability distribution for all the fingers' fingerprint type. (d For each of four fingers of identical twins, the probability of having same fingerprint type is similar.

  3. The Qingdao Twin Registry

    DEFF Research Database (Denmark)

    Duan, Haiping; Ning, Feng; Zhang, Dongfeng;

    2013-01-01

    In 1998, the Qingdao Twin Registry was initiated as the main part of the Chinese National Twin Registry. By 2005, a total of 10,655 twin pairs had been recruited. Since then new twin cohorts have been sampled, with one longitudinal cohort of adolescent twins selected to explore determinants...... of metabolic disorders and health behaviors during puberty and young adulthood. Adult twins have been sampled for studying heritability of multiple phenotypes associated with metabolic disorders. In addition, an elderly twin cohort has been recruited with a focus on genetic studies of aging-related phenotypes...

  4. Sibling power: influence of older siblings' persuasive appeals on younger siblings' judgements about risk taking behaviours.

    Science.gov (United States)

    Morrongiello, B. A.; Bradley, M. D.

    1997-01-01

    OBJECTIVES: Although many injuries happen when school age children are away from home and in the company of other children, we know surprisingly little about interpersonal influences on children's risk taking decisions. The aim of the present study was to examine the influence of older siblings' persuasive appeals on young children's decisions about engaging in behaviours that could threaten their physical safety. METHODS: Forty same sex sibling pairs participated. Children were shown drawings of play scenes (bicycling, river crossing, and sledding), with each depicting lower and higher risk paths of travel. Children of 8 years made initial decisions as to which paths they would take. Subsequently, their older sibling acted as a confederate and tried to persuade them to change their decisions. RESULTS: After the appeals of older siblings, younger children significantly shifted their decisions: choices of less risky paths replaced the initial selection of more risky paths, and vice versa. A positive sibling relationship was predictive of younger siblings' decision changes. Boys and girls were equally effective in persuasion but they did so using different types of arguments, with boys communicating primarily appeals to fun and girls emphasizing appeals to safety. CONCLUSIONS: These findings highlight the effect that older siblings can have on risk taking decisions of younger siblings. Accordingly, they document the importance of considering the interpersonal context of risk taking when designing interventions to reduce injuries among elementary schoolchildren. Images PMID:9113843

  5. Warburg micro syndrome in siblings from India

    Directory of Open Access Journals (Sweden)

    Prabhjot Kaur Sekhon

    2016-01-01

    Full Text Available Warburg syndrome is a rare disorder characterized by microcephaly, microcornea, congenital cataract, developmental delay, and hypogonadism. Here, we report two siblings from India who presented with developmental delay, microcornea, microphthalmia, and bilateral congenital cataracts, born to the third-degree consanguineously married couple. Both children had hypoplasia of corpus callosum. In this report, we aim to highlight and compare clinical features of these two cases with previously reported cases.

  6. Accommodative spasm in siblings: A unique finding

    Directory of Open Access Journals (Sweden)

    Rutstein Robert

    2010-01-01

    Full Text Available Accommodative spasm is a rare condition occurring in children, adolescents, and young adults. A familial tendency for this binocular vision disorder has not been reported. I describe accommodative spasm occurring in a brother and sister. Both children presented on the same day with complaints of headaches and blurred vision. Treatment included cycloplegia drops and bifocals. Siblings of patients having accommodative spasm should receive a detailed eye exam with emphasis on recognition of accommodative spasm.

  7. Twinning of Polymer Crystals Suppressed by Entropy

    Directory of Open Access Journals (Sweden)

    Nikos Ch. Karayiannis

    2014-09-01

    Full Text Available We propose an entropic argument as partial explanation of the observed scarcity of twinned structures in crystalline samples of synthetic organic polymeric materials. Polymeric molecules possess a much larger number of conformational degrees of freedom than low molecular weight substances. The preferred conformations of polymer chains in the bulk of a single crystal are often incompatible with the conformations imposed by the symmetry of a growth twin, both at the composition surfaces and in the twin axis. We calculate the differences in conformational entropy between chains in single crystals and chains in twinned crystals, and find that the reduction in chain conformational entropy in the twin is sufficient to make the single crystal the stable thermodynamic phase. The formation of cyclic twins in molecular dynamics simulations of chains of hard spheres must thus be attributed to kinetic factors. In more realistic polymers this entropic contribution to the free energy can be canceled or dominated by nonbonded and torsional energetics.

  8. Twin Jet

    Science.gov (United States)

    Henderson, Brenda; Bozak, Rick

    2010-01-01

    Many subsonic and supersonic vehicles in the current fleet have multiple engines mounted near one another. Some future vehicle concepts may use innovative propulsion systems such as distributed propulsion which will result in multiple jets mounted in close proximity. Engine configurations with multiple jets have the ability to exploit jet-by-jet shielding which may significantly reduce noise. Jet-by-jet shielding is the ability of one jet to shield noise that is emitted by another jet. The sensitivity of jet-by-jet shielding to jet spacing and simulated flight stream Mach number are not well understood. The current experiment investigates the impact of jet spacing, jet operating condition, and flight stream Mach number on the noise radiated from subsonic and supersonic twin jets.

  9. Agenesis of Permanent Mandibular Central Incisors: A Concordant Condition in Siblings

    Science.gov (United States)

    Namineni, Srinivas; Tupalli, Abhinaya Reddy; Challa, Santhosh Kumar

    2016-01-01

    ABSTRACT Concordance is an identical expression of phenotype in two related individuals. Concordance expression of hypodontia is an uncommon condition where associated individuals are affected with exactly similar kind and number of missing teeth. There is very limited documentation of this condition either in twins or in siblings, and literature shows paucity of data with regard to this anomaly. To the best of our knowledge, there is only one such case reported in the literature, which has actually showed similar missing lower central incisors in siblings. This report presents a case of two girl siblings aged 11 and 13 years with congenital bilateral missing of permanent mandibular central incisors, which is an absolute concordant condition. Apart from discussing etiology, clinical implications and management, this article highlights the significance of concordant and discordant condition of hypodontia and expression of this condition in twins and siblings. How to cite this article: Kagitha PK, Namineni S, Tupalli AR, Challa SK. Agenesis of Permanent Mandibular Central Incisors: A Concordant Condition in Siblings. Int J Clin Pediatr Dent 2016;9(1):74-77. PMID:27274160

  10. The twin paradox with macroscopic clocks in superconducting circuits

    CERN Document Server

    Lindkvist, Joel; Fuentes, Ivette; Dragan, Andrzej; Svensson, Ida-Maria; Delsing, Per; Johansson, Göran

    2014-01-01

    Time dilation, a striking prediction of Einstein's relativity, plays an important role in applications such as the Global Positioning System. One of the most compelling consequences of time dilation is known as the twin paradox, where a twin at rest ages more than her sibling travelling at relativistic speeds. In this paper, we propose an implementation of the twin paradox in superconducting circuits with velocities as large as a few percent of the speed of light. Ultrafast modulation of the boundary conditions for the electromagnetic field in a microwave cavity simulates a clock moving at relativistic speeds. While previous demonstrations of this effect involve point-like clocks, our superconducting cavity has a finite length, allowing us to investigate the role of clock size as well as interesting quantum effects on time dilation. In particular, our theoretical results show that the travelling twin ages slower for larger cavity lengths and that quantum particle creation, known in this context as the dynamic...

  11. Situs Inversus Totalis in Twins: A Brief Review and a Life History / Twin Research: Twin Studies of Trisomy 21; Monozygotic Twin Concordance for Bilateral Coronoid Hyperplasia; Prenatal Hormonal Effects in Mixed-Sex Non-Human Primate Litters; Insurance Mandates and Twinning After In Vitro Fertilization / News Reports: First Report of Identical Twin Puppies; Twins Sisters Turn 100; Remembering an Identical Twin Production Designer; New York City Marathon Quadruplets.

    Science.gov (United States)

    Segal, Nancy L

    2017-02-01

    The presence of situs inversus totalis (full reversal of internal organs) in twins is briefly reviewed. Information gathered from 35-year-old monozygotic (MZ) female twin pair discordant for this condition is presented. This is followed by summaries of research on the frequency of trisomy 21 (Down syndrome) in twins, the first case of MZ twin concordance for bilateral coronoid hyperplasia, prenatal hormonal effects in mixed-sex non-human primate litters, and links between insurance mandates and twinning following in vitro fertilization. The final section of this article describes twin-related events reported in the news, namely, the first recorded birth of identical twin puppies; the 100th birthday celebration of a pair of fraternal female twins, the passing of an award-winning identical twin production designer, and the first running of the New York City Marathon by a set of quadruplets.

  12. Familial Mediterranean fever in siblings.

    Science.gov (United States)

    Özçakar, Z Birsin; Erdogan, Beyza Doganay; Elhan, Atilla H; Yalçinkaya, Fatoş

    2012-11-01

    Genetic and environmental factors have been implicated in disease severity and development of amyloidosis in familial Mediterranean fever (FMF). We investigated similarities in clinical characteristics, disease severity, and treatment response within siblings with FMF. The study group consisted of 2 or more siblings who were followed in our center with the diagnosis of FMF. Siblings were evaluated for demographic data, clinical and laboratory disease features, genetic analysis of MEFV mutations, and disease severity score. The intraclass correlation coefficient (ICC), which can be interpreted as the expected correlation between 2 siblings, was used to reflect within-family similarity. The study included 67 pediatric patients from 31 different families. When we investigated the similarity of siblings after adjusting for genetic effects, we found very low ICC with p > 0.05 in the majority of clinical features, disease severity, and colchicine dosages. However, age at disease onset, age at onset of therapy, attack-free acute-phase reactant levels, and presence of amyloidosis were found to be similar within siblings (relatively high ICC with p < 0.05). Siblings with FMF had different clinical findings and disease severity. They had similar amyloidogenic potential, proven by both similar presence of amyloid and increased levels of acute-phase reactants between attacks. Our findings strongly support that genetic factors may be more dominant in the development of amyloidosis.

  13. Relative Power in Sibling Relationships across Adolescence

    Science.gov (United States)

    Lindell, Anna K.; Campione-Barr, Nicole

    2017-01-01

    During childhood, older siblings typically hold a more powerful position in their relationship with their younger siblings, but these relationships are thought to become more egalitarian during adolescence as siblings begin to prepare for their relationships as adults and as younger siblings become more socially and cognitively competent. Little…

  14. Sibling Self-Disclosure in Early Adolescence.

    Science.gov (United States)

    Howe, Nina; Aquan-Assee, Jasmin; Bukowski, William M.; Rinaldi, Christina M.; Lehoux, Pascale M.

    2000-01-01

    Studied sibling-directed self-disclosure of 40 preadolescents through interviews, a questionnaire, and subjects' daily diaries. Found that warmth in sibling relationship was most strongly associated with sibling disclosure, but not with rivalry, conflict, or power. Daily sibling disclosures were more strongly associated with reports of unhappy…

  15. Deformation twinning in monazite

    Energy Technology Data Exchange (ETDEWEB)

    Hay, R.S.; Marshall, D.B

    2003-10-20

    Polycrystalline monazite (LaPO{sub 4}) was deformed at room temperature by a spherical indenter. Deformation twins were identified by TEM in 70 grains. Five twin planes were found: (100) was by far the most common; (001) and (120) were less common; (122-bar)was rare, and kinks in (120) twins were identified as irrational '(483)' twin planes. The twinning modes on these planes were inferred from the expression of twinning shear at free surfaces, predictions of classical deformation twinning theory, and various considerations of twin morphology and crystal structure. Atomic shuffle calculations that allow formation of either a glide plane or a mirror plane at the twin interface were used to analyze twin modes. The inferred twin modes all have small atomic shuffles. For (001) twins, the smallest shuffles were obtained with a glide plane at the interface, with displacement vector R=((1)/(2))[010]. The results do not uniquely define a twin mode on (100), leaving open the possibility of more than one mode operating on this plane. Factors that may determine the operative deformation twinning modes are discussed. Crystal structure considerations suggest that the relative abundance of twinning modes may correlate with low shear modulus on the twin plane in the direction of twinning shear, and with a possible low-energy interface structure consisting of a layer of xenotime of one half-unit-cell thickness that could form at (100) and (001) twins. The three most common twins have low strains to low {sigma} coincidence site lattices (CSLs)

  16. Perceived sibling relationships of sexual minority youth.

    Science.gov (United States)

    Toomey, Russell B; Richardson, Rhonda A

    2009-01-01

    The purpose of this study was to examine the relationships of sexual minority youth and their siblings. The participants were 56 lesbian, gay, bisexual, or transgender individuals ranging in age from 18 to 24 years, who reported information about a total of 107 siblings. Respondents completed a demographic data questionnaire as well as adapted versions of the Sibling Closeness Scale (SCS) and the Sibling Approval of Sexual Behavior Scale (SASBS) to describe their relationship with each of their siblings. Analyses examined birth order and gender in relation to outness to siblings as well as sibling closeness and approval. Results provide information about disclosure of LGBT status to siblings, elements of closeness and acceptance in sibling relationships of sexual minority youth, and the significance of gender and birth order in these sibling relationships.

  17. Intellectual similarity of virtual twin pairs: Developmental trends

    OpenAIRE

    2007-01-01

    Virtual twins (VTs) are same-age unrelated siblings reared together from infancy who replicate twinship, but without the genetic relatedness. A 2005 report from the ongoing Fullerton Virtual Twin Study found an IQ intraclass correlation of .26 (p < .01, n = 113 pairs) and a within-pair difference of 13.22 IQ points. The average age of VTs in that study was 8.10 years (SD = 8.56, range: 4.01–54.84 years). An opportunity to retest members of 43 VT pairs, 1.70–8.96 years after their time 1 asses...

  18. Utilizing twins as controls for non-twin case-materials in genome wide association studies.

    Directory of Open Access Journals (Sweden)

    Andrea Ganna

    Full Text Available Twin registries around the globe have collected DNA samples from large numbers of monozygotic and dizygotic twins. The twin sample collections are frequently used as controls in disease-specific studies together with non-twins. This approach is unbiased under the hypothesis that twins and singletons are comparable in terms of allele frequencies; i.e. there are no genetic variants associated with being a twin per se. To test this hypothesis we performed a genome-wide association study comparing the allele frequency of 572,352 single nucleotide polymorphisms (SNPs in 1,413 monozygotic (MZ and 5,451 dizygotic (DZ twins with 3,720 healthy singletons. Twins and singletons have been genotyped using the same platform. SNPs showing association with being a twin at P-value < 1 × 10(-5 were selected for replication analysis in 1,492 twins (463 MZ and 1,029 DZ and 1,880 singletons from Finland. No SNPs reached genome-wide significance (P-value < 5 × 10(-8 in the main analysis combining MZ and DZ twins. In a secondary analysis including only DZ twins two SNPs (rs2033541 close to ADAMTSL1 and rs4149283 close to ABCA1 were genome-wide significant after meta-analysis with the Finnish population. The estimated proportion of variance on the liability scale explained by all SNPs was 0.08 (P-value=0.003 when MZ and DZ were considered together and smaller for MZ (0.06, P-value=0.10 compared to DZ (0.09, P-value=0.003 when analyzed separately. In conclusion, twins and singletons can be used in genetic studies together with general population samples without introducing large bias. Further research is needed to explore genetic variances associated with DZ twinning.

  19. The Norwegian Twin Registry.

    Science.gov (United States)

    Nilsen, Thomas S; Brandt, Ingunn; Magnus, Per; Harris, Jennifer R

    2012-12-01

    Norway has a long-standing tradition in twin research, but the data collected in several population-based twin studies were not coordinated centrally or easily accessible to the scientific community. In 2009, the Norwegian Twin Registry was established at the Norwegian Institute of Public Health (NIPH) in Oslo with the purpose of creating a single research resource for Norwegian twin data. As of today, the Norwegian Twin Registry contains 47,989 twins covering birth years 1895-1960 and 1967-1979; 31,440 of these twins consented to participate in health-related research. In addition, DNA from approximately 4,800 of the twins is banked at the NIPH biobank and new studies are continually adding new data to the registry. The value of the Norwegian twin data is greatly enhanced by the linkage opportunities offered by Norway's many nationwide registries, spanning a broad array of medical, demographic, and socioeconomic information.

  20. Sibling Dependence, Uncertainty and Education

    DEFF Research Database (Denmark)

    Lilleør, Helene Bie

    investigates the effects of future income uncertainty on sibling dependence in the schooling decisions of rural households in developing countries. Schooling tends to direct skills towards future urban employment, whereas traditional rural education or on-farm learning-by-doing tends to direct skills towards...... to a three period setting. This allows me to explore the natural sequentiality in the schooling decision of older and younger siblings. The model can generate testable empirical implications, which can be taken to any standard cross-sectional data set. I find empirical evidence of negative sibling dependence...... in the educational decision, which is consistent with a human capital portfolio theory of risk diversification and which cannot be explained by sibling rivalry over scarce resources for credit constrained households. The paper thus provides a complementary explanation to why enrolment rates in developing countries...

  1. Dichorionic Diamniotic Twin Pregnancy Discordant for Bladder Exstrophy

    Directory of Open Access Journals (Sweden)

    William Tu

    2009-01-01

    Full Text Available A 38 year-old woman presented with a dichorionic diamniotic twin pregnancy at gestational age of 32 weeks concerning for an abdominal wall mass in one of the twins. Initial ultrasound evaluation was suspicious for an omphalocele, but the affected twin was found to have bladder exstrophy at birth. This illustrates the difficulties of accurate prenatal diagnosis of bladder exstrophy in a twin pregnancy at a late gestation.

  2. TWIN GESTATION : A CHALLENGING TASK

    Directory of Open Access Journals (Sweden)

    Vrunda V.

    2015-03-01

    Full Text Available INTRODUCTION In the era of modern obstetrics when multiple pregnancies are on increase it is very important to know the incidence and obstetric outcomes of twin deliveries. Twin pregnancy is still associated with increased maternal and perinatal morbidity and mortality as well as healthcare costs . ( 1 , 2 , 3 MATERIALS AND METHODS : This is a r etrospective study of twin deliveries done in the rural medical college teaching hospital over a period of 3 years. RESULTS : During the study period , incidence of twin delivery was 19.37 per 1000 deliveries. Majority cases of twins were young primies in ag e group (20 - 30 years . Preterm delivery occurred in 68% cases and was therefore , the most common morbidity followed by anaemia (38% and PIH (28%. Most common presentation was vertex (66% and malpresentation were present in 44% of cases. 54% were deliver ed by caesarean section. In 88% second baby delivered within 15 minutes. Uterine inertia , PROM , fetal distress , PPH , cord prolapse and abruption were complications during labour. There was no maternal mortality in present study. Average weight of first baby was 1679.63 gms and 2 nd baby was 1586.94 gms. Perinatal mortality of 1 st baby was 27.55 for 1 st baby and 37.25% for 2 nd baby . Average gestational age for patients in whom cervical encirclage was done was 34 weeks. CONCLUSION: P reterm delivery and low birth weight babies are main challenges to the obstetrician. Incidence of LSCS is quite high with malpresentation of leading (twin A baby is a major indication for LSCS . The use of antenatal care services and good intrapartum mana gement will help improve outcome in twin pregnancies.

  3. Twin-twin transfusion syndrome: neurodevelopmental screening test

    Directory of Open Access Journals (Sweden)

    Amabile Vessoni Arias

    2015-03-01

    Full Text Available Objective To assess the neurodevelopmental functions (cognition, language and motor function of survivors of twin-twin transfusion syndrome (TTTS. Method Observational cross-sectional study of a total of 67 monochorionic diamniotic twins who underwent fetoscopic laser coagulation (FLC for treatment of TTTS. The study was conducted at the Center for Investigation in Pediatrics (CIPED, Universidade Estadual de Campinas. Ages ranged from one month and four days to two years four months. Bayley Scales of Infant and Toddler Development Screening Test-III, were used for evaluation. Results Most children reached the competent category and were classified as having appropriate performance. The preterm children scored worse than term infants for gross motor subtest (p = 0.036. Conclusion The majority of children reached the expected development according to their age. Despite the good neurodevelopment, children classified at risk should be monitored for development throughout childhood.

  4. Acardiac Twinning (Twin Reversed Arterial Perfusion Sequence: A Review of Prenatal Management

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2005-06-01

    Full Text Available Acardiac twinning, or the twin reversed arterial perfusion (TRAP sequence, occurs in 1% of monozygotic twins, or 1 in 35,000 births. It is caused by the development of arterioarterial vascular anastomoses between the umbilical arteries of monozygotic twins early in embryogenesis. The pump twin may be associated with congenital anomalies and chromosomal abnormalities. Therefore, it is recommended that prenatal genetic testing be offered whenever pregnancy is complicated by acardiac twinning. The treatment options for acardiac twinning include observation, medical management, amniodrainage, and invasive treatment such as hysterotomy with selective delivery of the acardiac twin, intrafetal ablation of the acardiac twin by alcohol, laser, thermocoagulation or radiofrequency, fetoscope-guided funicular occlusion by ligation, laser or thermocoagulation, and ultrasound-guided funicular occlusion by ligation, cord compression, thermocoagulation or intrafunicular embolization with foreign bodies. If invasive treatment is indicated, the simplicity, safety, and efficacy of the chosen technique should be considered. An intrafetal approach has been shown to be superior to a funicular occlusion approach. Ultrasound-guided intrafetal laser ablation or radiofrequency ablation is believed to be the treatment of choice based on currently available data. This review emphasizes the necessity to carefully search for any possible associated anomaly in the pump twin by both genetic testing and sonographic examination, and to prudently consider invasive treatment only in pregnancies which would potentially benefit from the prenatal intervention.

  5. Profile of asymmetrical retinopathy of prematurity in twins

    Directory of Open Access Journals (Sweden)

    Azad Rajvardhan

    2010-01-01

    Full Text Available Background: In twin births, both babies have the same gestational age and pre-natal conditions. However, twins may develop a varied retinopathy of prematurity (ROP course depending on birth weight and other systemic factors. Objective: To study the profile of asymmetric ROP in twins Design: Retrospective study Setting: Tertiary ROP referral eye hospital. Materials and Methods: The profile of 56 pairs of twins with ROP were studied and analyzed for differences in zone or need for treatment, while studying possible causes for the varied outcome. Results: In 45 pairs of twins (80% the disease progressed identically in both eyes, while in 11 pairs (20% the ROP showed differences in zone or need for treatment. Four of these pairs were discordant. In 3 of these 4 pairs, the heavier birth weight twin had a more severe ROP course. Conclusions: Twins can present with asymmetric ROP course, and it is therefore essential to examine both twins as per screening protocols.

  6. TWIN PREGNANCY WITH ACARDIUS ANCEPS

    Directory of Open Access Journals (Sweden)

    Padma

    2014-02-01

    Full Text Available Acardiac twin is an anomaly unique to monochorionic multiple pregnancies, characterized by formation of malformed fetus with an absent or rudimentary (nonfunctional heart. Acardiac twinning, often results from abnormal placental vascular anastomoses. A 20 year old primigravida admitted to the department of Obstetrics and Gynecology S .S. Medical College, Rewa, on 26th July 2012 at the gestation of 34 week with spontaneous monochorionic monoamniotic twin pregnancy and fetal acardius with oligohydramnios. Patient was taking her treatment from private Hospital; acardius was diagnosed at 27 week due to late booking. In view of oligohydramnios and hypoxic changes in color Doppler, elective LSCS was done on 28/7/13 at 34 week 2 day, after betnesol coverage. She delivered a live, healthy, female child with good APGAR score having apparently no congenital anomaly, with a birth weight of 2.3 kg .The other twin was fetus acardius, of about900 gm. with head and face partially developed . Upper limb was rudimentary and lower limb was partially developed and malformed. External genitalia were developed as female. Placenta was monochorionic and monoamniotic, weighing500 gm. The umbilical cord of the normal twin was20 cm with central attachment, while the other umbilical cord was10 cm long with peripheral attachment

  7. The Danish Twin Register

    DEFF Research Database (Denmark)

    Kyvik, K O; Christensen, Kaare; Skytthe, A;

    1996-01-01

    BACKGROUND: Population based twin registers represent a valuable tool for genetic epidemiological research, since twin studies aim at separating the effect of genes and environment for complex traits. The Danish Twin Register's history, size, ascertainment and completeness of data, as well as data...... accessibility and availability are described. RESULTS: The Danish Twin Register comprises 14,051 twin pairs born 1870-1930, representing all twins surviving to age six years, and 20,888 twin pairs born 1953-1982, representing 75% of those born 1953-1967 and 95% of those born 1968-1982. The birth cohorts 1931......-1952 og 1983-1993 are being ascertained at the moment. The register is available for research given certain conditions are fulfilled. CONCLUSION: This register will in a few years be the most comprehensive twin register in the world. It is a very valuable Danish research resource....

  8. The Danish Twin Register

    DEFF Research Database (Denmark)

    Kyvik, K O; Christensen, Kaare; Skytthe, A

    1996-01-01

    BACKGROUND: Population based twin registers represent a valuable tool for genetic epidemiological research, since twin studies aim at separating the effect of genes and environment for complex traits. The Danish Twin Register's history, size, ascertainment and completeness of data, as well as data...... accessibility and availability are described. RESULTS: The Danish Twin Register comprises 14,051 twin pairs born 1870-1930, representing all twins surviving to age six years, and 20,888 twin pairs born 1953-1982, representing 75% of those born 1953-1967 and 95% of those born 1968-1982. The birth cohorts 1931......-1952 og 1983-1993 are being ascertained at the moment. The register is available for research given certain conditions are fulfilled. CONCLUSION: This register will in a few years be the most comprehensive twin register in the world. It is a very valuable Danish research resource....

  9. Twins or two single children

    Directory of Open Access Journals (Sweden)

    2002-08-01

    Full Text Available Based on Swedish register data, we compared the influence of a twin birth on the divorce risk with the influence of the sequential birth of two single children. The divorce risk for a woman with a very young child was lower than the risk for women without children or women with children older than 3.5 years. This behaviour was essentially independent of the number of children and whether or not the woman gave birth to twins. The effect of parity was much smaller than the effect of child age. The influence of twins on the divorce risk appeared to fall between that of a first and a second singleton.

  10. Twin TQFTs and Frobenius Algebras

    Directory of Open Access Journals (Sweden)

    Carmen Caprau

    2013-01-01

    Full Text Available We introduce the category of singular 2-dimensional cobordisms and show that it admits a completely algebraic description as the free symmetric monoidal category on a twin Frobenius algebra, by providing a description of this category in terms of generators and relations. A twin Frobenius algebra (C,W,z,z∗ consists of a commutative Frobenius algebra C, a symmetric Frobenius algebra W, and an algebra homomorphism z:C→W with dual z∗:W→C, satisfying some extra conditions. We also introduce a generalized 2-dimensional Topological Quantum Field Theory defined on singular 2-dimensional cobordisms and show that it is equivalent to a twin Frobenius algebra in a symmetric monoidal category.

  11. Monochorionic twin pregnancies

    NARCIS (Netherlands)

    Hack, K.E.A.

    2008-01-01

    Following widespread application of assisted reproductive technology modalities and the increased age of motherhood, the incidence of twin gestations has increased markedly. Twins are either monozygotic or dizygotic. Dizygotic (i.e. fraternal) twins result from the fertilization of two different egg

  12. Progeria (Hutchison - Gilford syndrome in siblings: In an autosomal recessive pattern of inheritance

    Directory of Open Access Journals (Sweden)

    Raghu Tanjore

    2001-09-01

    Full Text Available Progeria is an autosomal dominant, premature aging syndrome. Six and three year old female siblings had sclcrodermatous changes over the extremities, alopecia, beaked nose, prominent veins and bird-like facies. Radiological features were consistent with features of progeria. The present case highlights rarity of progeria in siblings with a possible autosomal recessive pattern.

  13. Fetal Aneuploidy Detection by Cell-Free DNA Sequencing for Multiple Pregnancies and Quality Issues with Vanishing Twins

    Directory of Open Access Journals (Sweden)

    Sebastian Grömminger

    2014-06-01

    Full Text Available Non-invasive prenatal testing (NIPT by random massively parallel sequencing of maternal plasma DNA for multiple pregnancies is a promising new option for prenatal care since conventional non-invasive screening for fetal trisomies 21, 18 and 13 has limitations and invasive diagnostic methods bear a higher risk for procedure related fetal losses in the case of multiple gestations compared to singletons. In this study, in a retrospective blinded analysis of stored twin samples, all 16 samples have been determined correctly, with four trisomy 21 positive and 12 trisomy negative samples. In the prospective part of the study, 40 blood samples from women with multiple pregnancies have been analyzed (two triplets and 38 twins, with two correctly identified trisomy 21 cases, confirmed by karyotyping. The remaining 38 samples, including the two triplet pregnancies, had trisomy negative results. However, NIPT is also prone to quality issues in case of multiple gestations: the minimum total amount of cell-free fetal DNA must be higher to reach a comparable sensitivity and vanishing twins may cause results that do not represent the genetics of the living sibling, as described in two case reports.

  14. Mutagen sensitivity has high heritability: evidence from a twin study.

    Science.gov (United States)

    Wu, Xifeng; Spitz, Margaret R; Amos, Christopher I; Lin, Jie; Shao, Lina; Gu, Jian; de Andrade, Mariza; Benowitz, Neal L; Shields, Peter G; Swan, Gary E

    2006-06-15

    Despite numerous studies showing that mutagen sensitivity is a cancer predisposition factor, the heritability of mutagen sensitivity has not been clearly established. In this report, we used a classic twin study design to examine the role of genetic and environmental factors on the mutagen sensitivity phenotype. Mutagen sensitivity was measured in peripheral blood lymphocytes from 460 individuals [148 pairs of monozygotic (MZ) twins, 57 pairs of dizygotic (DZ) twins, and 50 siblings]. The intraclass correlation coefficients were all significantly higher in MZ twins than in dizygotes (DZ pairs and MZ-sibling pairs combined) for sensitivity to four different mutagen challenges. Applying biometric genetic modeling, we calculated a genetic heritability of 40.7%, 48.0%, 62.5%, and 58.8% for bleomycin, benzo[a]pyrene diol epoxide, gamma-radiation, and 4-nitroquinoline-1-oxide sensitivity, respectively. This study provides the strongest and most direct evidence that mutagen sensitivity is highly heritable, thereby validating the use of mutagen sensitivity as a cancer susceptibility factor.

  15. Family study of monozygotic twins affected by pemphigus vulgaris.

    Science.gov (United States)

    Salathiel, Adriana Martinelli; Brochado, Maria José Franco; Kim, Olivia; Deghaide, Neifi Hassan Saloum; Donadi, Eduardo Antonio; Roselino, Ana Maria

    2016-07-01

    Rare are the family studies that include siblings affected by pemphigus vulgaris (PV) and in whom HLA class II alleles are related. HLA-DR and -DQ genotyping and profiling of antibodies against desmogleins (Dsg) 1 and Dsg3 were performed in ten members of a family including monozygotic twins affected by PV. The twin sisters were heterozygotes; they presented the haplotypes most commonly associated with increased susceptibility to PV (DRB1∗04:02-DQA1∗03:01-DQB1∗03:02 and DRB1∗14:04-DQA1∗01:01-DQB1∗05:03). Their parents and five siblings had only one or none of these two haplotypes in combination with the alleles or haplotypes associated with resistance to PV (DRB1∗07:01-DQA1∗02:01-DQB1∗02:02 and DRB1∗13:01-DQA1∗01:03-DQB1∗06:03). Only the monozygotic twins presented IgG antibodies against both Dsg1 and Dsg3. According to our knowledge based on a review of published literature on the topic, this is the first report of PV affecting monozygotic twins.

  16. Sibling Relationship Predictors of Academic Achievement in Adolescents

    OpenAIRE

    Dagys Pajoluk, Natasha

    2013-01-01

    During adolescence older siblings who are close in age may serve as examples to emulate or become different from. Key features of the sibling relationship that may promote similar sibling outcomes include sibling intimacy, older sibling support, younger sibling image of the older sibling, and self-reported social learning and differentiation. The goal of this dissertation was first to (a) examine whether older sibling support represents a single or multiple factors and then to (b) investiga...

  17. Disease-Concordant Twins Empower Genetic Association Studies.

    Science.gov (United States)

    Tan, Qihua; Li, Weilong; Vandin, Fabio

    2017-01-01

    Genome-wide association studies with moderate sample sizes are underpowered, especially when testing SNP alleles with low allele counts, a situation that may lead to high frequency of false-positive results and lack of replication in independent studies. Related individuals, such as twin pairs concordant for a disease, should confer increased power in genetic association analysis because of their genetic relatedness. We conducted a computer simulation study to explore the power advantage of the disease-concordant twin design, which uses singletons from disease-concordant twin pairs as cases and ordinary healthy samples as controls. We examined the power gain of the twin-based design for various scenarios (i.e., cases from monozygotic and dizygotic twin pairs concordant for a disease) and compared the power with the ordinary case-control design with cases collected from the unrelated patient population. Simulation was done by assigning various allele frequencies and allelic relative risks for different mode of genetic inheritance. In general, for achieving a power estimate of 80%, the sample sizes needed for dizygotic and monozygotic twin cases were one half and one fourth of the sample size of an ordinary case-control design, with variations depending on genetic mode. Importantly, the enriched power for dizygotic twins also applies to disease-concordant sibling pairs, which largely extends the application of the concordant twin design. Overall, our simulation revealed a high value of disease-concordant twins in genetic association studies and encourages the use of genetically related individuals for highly efficiently identifying both common and rare genetic variants underlying human complex diseases without increasing laboratory cost. © 2016 John Wiley & Sons Ltd/University College London.

  18. Life course preferences, sibling ties, and the geographical dispersion of sibling networks

    NARCIS (Netherlands)

    Blaauboer, M.; Strömgren, M.; Stjernström, O.

    2013-01-01

    Using Swedish register data, we analyse how life course preferences and sibling ties are related to the geographical dispersion of siblings. We argue that life course preferences and sibling ties are influenced by siblings' sociodemographic characteristics, by similarities and differences between

  19. Contributors to Adult Sibling Relationships and Intention to Care of Siblings of Individuals with Down Syndrome

    Science.gov (United States)

    Cuskelly, Monica

    2016-01-01

    The contribution of childhood sibling relationships to adult sibling relationships and intention to provide care was investigated in a sample in which one member of each dyad had Down syndrome. Thirty-nine adult siblings of an adult with Down syndrome who had participated in a study of sibling relationships in childhood/adolescence provided data…

  20. Chronic mercury poisoning: Report of two siblings

    Directory of Open Access Journals (Sweden)

    Yilmaz Cahide

    2010-01-01

    Full Text Available Mercury exists as organic inorganic and elementary forms in nature and is one of the most toxic metals that are poisonous for human beings. Mercury is commonly used in many different sectors of industry such as in insects formulas, agriculture products, lamps, batteries, paper, dyes, electrical/electronic devices, jewelry, and in dentistry. In this study, two siblings (one a 7-year-old boy and the other a 13 years old girl are reported who developed chronic mercury poisoning as a result of long-term contact with batteries. Our aim is to emphasize the importance of mercury poisoning that is extremely rarely seen in childhood.

  1. Bullying among Siblings: The Role of Personality and Relational Variables

    Science.gov (United States)

    Menesini, Ersilia; Camodeca, Marina; Nocentini, Annalaura

    2010-01-01

    This study aimed to investigate: (1) the influence of gender, sibling age, and sibling gender on sibling bullying and victimization; (2) the links between personality characteristics, quality of the sibling relationship, and sibling bullying/victimization; (3) the association between sibling and school bullying/victimization, and the direct and…

  2. Sibling Conflict Resolution Skills: Assessment and Training

    Science.gov (United States)

    Thomas, Brett W.; Roberts, Mark W.

    2009-01-01

    Sibling conflict can rise to the level of a clinical problem. In Phase 1 a lengthy behavioral role-play analog sampling child reactions to normal sibling conflicts was successfully shortened. In Phase 2 normal children who lacked sibling conflict resolution skills were randomly assigned to a Training or Measurement Only condition. Training…

  3. Combined effects of multiple linked loci on pairwise sibling tests.

    Science.gov (United States)

    Tamura, Tomonori; Osawa, Motoki; Kakimoto, Yu; Ochiai, Eriko; Suzuki, Takanori; Nakamura, Takashi

    2017-01-01

    The advanced multiplex STR system, PowerPlex Fusion, includes four linked locus pairs. The conventional Identifiler system has one pair of linked loci. Therefore, sibling tests conducted using the advanced system might be more affected by linkage than those conducted using the conventional system. This study simulated single and combined effects of the four linked locus pairs on pairwise sibling tests. Simulated genotypes of 100,000 pairs of full siblings and nonrelatives were constructed according to allele frequencies of the Japanese population. The single linkage effect was evaluated for simulated genotype data by calculating both the likelihood ratio accounting for the linkage between two loci and the likelihood ratio ignoring the linkage. The combined effect was obtained by multiplication of the respective single effects. Furthermore, we investigated the possibility that ignoring the linkage affects subject classification by introducing a scale of the likelihood ratio into sibling tests. The single effect in the Identifiler analysis was 0.645-1.746 times if the linkage was ignored. Overestimations and underestimations were predictable from the identical-by-state status at two linked loci. The combined effect in the PowerPlex Fusion analysis was 0.217-7.390 times. Ignoring the linkage rarely caused a false conclusive or inconclusive result, even from PowerPlex Fusion analysis. Application of the advanced system improved sibling tests considerably. The additional examined loci were more beneficial than the adverse effect of the linkage derived from the four linked locus pairs.

  4. Knowledge data base system for twins study.

    Science.gov (United States)

    Reina, S; Miozza, F

    1994-01-01

    The medical research on twins, carried out at the Gregor Mendel Institute for Medical Genetics and Twin Study in Rome over the past four decades, has resulted in a vast collection of clinical paper records. A challenge was presented by the need for a more secure method of storage to preserve this enormously valuable historical and scientific patrimony and to render its contents more easily accessible for research purposes. We met the challenge by planning and developing the computerization of this material. New concepts, currently being explored in biomedical informatics, were applied to build a Knowledge Data Base System, using a fourth-generation language (SQL). This architecturally innovative computer system enables its users to manipulate data supplied, rather than just simply storing it. Based on heuristic relational criteria between variables and parameters, the system is employed to solve problems of sibling design analysis typically arising from twins' records, but is also equipped to meet future data base requirements. Another feature of the system is its users' ability to pull off data in the form of regular automated reports, which are distributed through a Local Area Network (LAN). Through a Bulletin Board System (BBS) and modem, any scientist (outside as well as within the Institute) is thus able to access data and exchange scientific information.

  5. Undiagnosed xiphopagus twins: a perinatal malady

    Directory of Open Access Journals (Sweden)

    Gowri Dorairajan

    2012-02-01

    Full Text Available Conjoined twins are a very rare entity. It is associated with poor survival rate in the presence of vital organ sharing. The entity can be diagnosed as early as the first trimester. A conjoined twin diagnosed late in labor is a malady with high perinatal mortality and maternal morbidity. We present one such case of xiphopagus twins. The management of a case diagnosed late in labor can be very challenging. Such obstetric challenges can be avoided by a meticulous early scan with a high index of suspicion, especially in the absence of separating membrane while scanning multiple pregnancies.

  6. What makes siblings different? The development of sibling differences in academic achievement and interests.

    Science.gov (United States)

    Jensen, Alexander C; McHale, Susan M

    2015-06-01

    To illuminate processes that contribute to the development of sibling differences, this study examined cross-lagged links between parents' beliefs about sibling differences in academic ability and differences between siblings' grade point averages (GPAs), and cross-lagged links between differences in siblings' GPAs and sibling differences in academic interests. Data were collected from mothers, fathers, firstborn youth (M age at Time 1 = 15.71, SD = 1.07), and secondborn youth (M age at Time 1 = 13.18, SD = 1.29) from 388 European American families on 3 annual occasions. Findings revealed that, after controlling for siblings' average grades and prior differences in performance, parents' beliefs about sibling differences in academic ability predicted differences in performance such that youth rated by parents as relatively more competent than their sibling earned relatively higher grades the following year. Siblings' relative school performance, however, did not predict parents' beliefs about differences between siblings' competencies. Further, after controlling for average interests and grades, sibling differences in GPA predicted differences in siblings' interests such that youth who had better grades than their siblings reported relatively stronger academic interests the following year. Differences in interest, however, did not predict sibling differences in GPA. Findings are discussed in terms the role of sibling dynamics in family socialization.

  7. Capturing the temporal sequence of interaction in young siblings.

    Directory of Open Access Journals (Sweden)

    Michal Perlman

    Full Text Available We explored whether young children exhibit subtypes of behavioral sequences during sibling interaction. Ten-minute, free-play observations of over 300 sibling dyads were coded for positivity, negativity and disengagement. The data were analyzed using growth mixture modeling (GMM. Younger (18-month-old children's temporal behavioral sequences showed a harmonious (53% and a casual (47% class. Older (approximately four-year-old children's behavior was more differentiated revealing a harmonious (25%, a deteriorating (31%, a recovery (22% and a casual (22% class. A more positive maternal affective climate was associated with more positive patterns. Siblings' sequential behavioral patterns tended to be complementary rather than reciprocal in nature. The study illustrates a novel use of GMM and makes a theoretical contribution by showing that young children exhibit distinct types of temporal behavioral sequences that are related to parenting processes.

  8. Quest for the lost siblings of the Sun

    Science.gov (United States)

    Liu, C.; Ruchti, G.; Feltzing, S.; Martínez-Barbosa, C. A.; Bensby, T.; Brown, A. G. A.; Portegies Zwart, S. F.

    2015-03-01

    Aims: The aim of this paper is to find lost siblings of the Sun by analyzing high resolution spectra. Finding solar siblings will enable us to constrain the parameters of the parental cluster and the birth place of the Sun in the Galaxy. Methods: The solar siblings can be identified by accurate measurements of metallicity, stellar age and elemental abundances for solar neighbourhood stars. The solar siblings candidates were kinematically selected based on their proper motions, parallaxes and colours. Stellar parameters were determined through a purely spectroscopic approach and partly physical method, respectively. Comparing synthetic with observed spectra, elemental abundances were computed based on the stellar parameters obtained using a partly physical method. A chemical tagging technique was used to identify the solar siblings. Results: We present stellar parameters, stellar ages, and detailed elemental abundances for Na, Mg, Al, Si, Ca, Ti, Cr, Fe, and Ni for 32 solar sibling candidates. Our abundances analysis shows that four stars are chemically homogenous together with the Sun. Technique of chemical tagging gives us a high probability that they might be from the same open cluster. Only one candidate - HIP 40317 - which has solar metallicity and age could be a solar sibling. We performed simulations of the Sun's birth cluster in analytical Galactic model and found that most of the radial velocities of the solar siblings lie in the range -10 ≤ Vr ≤ 10 km s-1, which is smaller than the radial velocity of HIP 40317 (Vr = 34.2 km s-1), under different Galactic parameters and different initial conditions of the Sun's birth cluster. The sibling status for HIP 40317 is not directly supported by our dynamical analysis. Based on observations made with Nordic Optical Telescope at La Palma under programme 44-014. Based on observations made with ESO VLT Kueyen Telescope at the Paranal observatory under program me ID 085.C-0062(A), 087.D-0010(A), and 088.B-0820(A

  9. Long-term effects of sibling incest.

    Science.gov (United States)

    Daie, N; Witztum, E; Eleff, M

    1989-11-01

    Although sexual abuse of children is recognized as a serious problem, sibling incest has received relatively little attention. A distinction has been made between power-oriented sibling incest and nurturance-oriented incest. The authors review the relevant literature and present four clinical examples. The cases illustrate the broad range of sibling incest and demonstrate its effects, including the long-term consequences for the perpetrator. Lasting difficulties in establishing and maintaining close relationships, especially sexual ones, are prominent features of each case. Without denying the occurrences of benign sex-play between siblings, the authors emphasize exploitation and abuse as pathogenic aspects of sibling incest.

  10. Malaysian Twin Registry.

    Science.gov (United States)

    Jahanfar, Shayesteh; Jaffar, Sharifah Halimah

    2013-02-01

    The National Malaysian Twin Registry was established in Royal College of Medicine, Perak, University Kuala Lumpur (UniKL) in June 2008 through a grant provided by UniKL. The general objective is to facilitate scientific research involving participation of twins and their family members in order to answer questions of health and wellbeing relevant to Malaysians. Recruitment is done via mass media, poster, and pamphlets. We now have 266 adult and 204 children twins registered. Several research projects including reproductive health study of twins and the role of co-bedding on growth and development of children are carried out. Registry holds annual activities for twins and seeks to provide health-related information for twins. We seek international collaboration.

  11. Perinatal hepatic infarction in twin-twin transfusion.

    LENUS (Irish Health Repository)

    O'Sullivan, M J

    2012-02-03

    We report a case of a twin pregnancy which was complicated by a twin-twin transfusion in which the recipient twin was noted to have an intra-abdominal echogenic mass. This twin died at two days of age of hepatic infarction. The donor twin was healthy at birth, at thirty weeks\\' gestation, and did not have any subsequent problems. Fetal intra-abdominal echogenicity may be a marker of hepatic infarction.

  12. Bullying in the family: sibling bullying.

    Science.gov (United States)

    Wolke, Dieter; Tippett, Neil; Dantchev, Slava

    2015-10-01

    Sibling relationships have a substantial and lasting effect on children's development. Many siblings experience some occasional conflict, however, up to 40% are exposed to sibling bullying every week, a repeated and harmful form of intrafamilial aggression. We review evidence on the precursors, factors relating to peer bullying, and mental health consequences of sibling bullying. Parenting quality and behaviour are the intrafamilial factors most strongly associated with bullying between siblings. Sibling bullying increases the risk of being involved in peer bullying, and is independently associated with concurrent and early adult emotional problems, including distress, depression, and self-harm. The effects appear to be cumulative, with those children bullied by both siblings and peers having highly increased emotional problems compared with those bullied by siblings or peers only, probably because they have no safe place to escape from bullying. The link between sibling and peer bullying suggests interventions need to start at home. Health professionals should ask about sibling bullying and interventions are needed for families to prevent and reduce the health burden associated with sibling bullying. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Infantile malignant osteopetrosis: A case report of three siblings

    Directory of Open Access Journals (Sweden)

    Sahil Jain

    2013-01-01

    Full Text Available Infantile malignant osteopetrosis, a rare hereditary, generalized disorder of bone characterized by a significant increase in the density of the skeletal tissues is described in three siblings. The incidence, genetic etiology, clinical, laboratory, radiological features, management and prognosis have been discussed.

  14. The Brazilian Twin Registry.

    Science.gov (United States)

    Ferreira, Paulo H; Oliveira, Vinicius C; Junqueira, Daniela R; Cisneros, Lígia C; Ferreira, Lucas C; Murphy, Kate; Ordoñana, Juan R; Hopper, John L; Teixeira-Salmela, Luci F

    2016-12-01

    The Brazilian Twin Registry (BTR) was established in 2013 and has impelled twin research in South America. The main aim of the initiative was to create a resource that would be accessible to the Brazilian scientific community as well as international researchers interested in the investigation of the contribution of genetic and environmental factors in the development of common diseases, phenotypes, and human behavior traits. The BTR is a joint effort between academic and governmental institutions from Brazil and Australia. The collaboration includes the Federal University of Minas Gerais (UFMG) in Brazil, the University of Sydney and University of Melbourne in Australia, the Australian Twin Registry, as well as the research foundations CNPq and CAPES in Brazil. The BTR is a member of the International Network of Twin Registries. Recruitment strategies used to register twins have been through participation in a longitudinal study investigating genetic and environmental factors for low back pain occurrence, and from a variety of sources including media campaigns and social networking. Currently, 291 twins are registered in the BTR, with data on demographics, zygosity, anthropometrics, and health history having been collected from 151 twins using a standardized self-reported questionnaire. Future BTR plans include the registration of thousands of Brazilian twins identified from different sources and collaborate nationally and internationally with other research groups interested on twin studies.

  15. Brain SCALE: brain structure and cognition: an adolescent longitudinal twin study into the genetic etiology of individual differences.

    Science.gov (United States)

    van Soelen, Inge L C; Brouwer, Rachel M; Peper, Jiska S; van Leeuwen, Marieke; Koenis, Marinka M G; van Beijsterveldt, Toos C E M; Swagerman, Suzanne C; Kahn, René S; Hulshoff Pol, Hilleke E; Boomsma, Dorret I

    2012-06-01

    From childhood into adolescence, the child's brain undergoes considerable changes in both structure and function. Twin studies are of great value to explore to what extent genetic and environmental factors explain individual differences in brain development and cognition. In The Netherlands, we initiated a longitudinal study in which twins, their siblings and their parents are assessed at three year intervals. The participants were recruited from The Netherlands Twin Register (NTR) and at baseline consisted of 112 families, with 9-year-old twins and an older sibling. Three years later, 89 families returned for follow-up assessment. Data collection included psychometric IQ tests, a comprehensive neuropsychological testing protocol, and parental and self-ratings of behavioral and emotional problems. Physical maturation was measured through assessment of Tanner stages. Hormonal levels (cortisol, luteinizing hormone, follicle-stimulating hormone, testosterone, and estrogens) were assessed in urine and saliva. Brain scans were acquired using 1.5 Tesla Magnetic Resonance Imaging (MRI), which provided volumetric measures and measures of cortical thickness. Buccal swabs were collected for DNA isolation for future candidate gene and genome-wide analysis studies. This article gives an overview of the study and the main findings. Participants will return for a third assessment when the twins are around 16 years old. Longitudinal twin-sibling studies that map brain development and cognitive function at well-defined ages aid in the understanding of genetic influences on normative brain development.

  16. BEHAVIOURAL, EMOTIONAL AND SOCIAL ADJUSTMENT IN SIBLINGS OF CHILDREN WITH AUTISM SPECTRUM DISORDER. A THEORETICAL REVIEW

    Directory of Open Access Journals (Sweden)

    Raquel Ruiz Aparicio

    2015-09-01

    Full Text Available Many individuals with Autism Spectrum Disorder (ASD have unique characteristics and very little is known about how these characteristics may influence the family and the behavioural, social and emotional adjustment of their siblings. The purpose of the current study is to focus on the siblings and to review the literature related to the behavioural, social and emotional adjustment of siblings of individuals with ASD. We have identified and analysed 24 articles to find the relevant results that may help us to understand the needs of these siblings. The findings suggest mixed results but they also bring to light a number of risk factors that could have an impact on the entire family and particularly on the siblings of children with ASD.

  17. The role of siblings in goal achievement in residential child care programs

    Directory of Open Access Journals (Sweden)

    Eduardo Martín

    2015-04-01

    Full Text Available Within the child welfare system, when groups of siblings are placed in residential care it is recommendedto keep them together. The goal of this work is to verify whether keeping groups of siblings together inresidential care is beneficial. The sample was made up of 167 children and adolescents who lived insupervised homes; 105 (62.9% were with siblings and 62 (37.1% were alone. We analyzed the evolution oftheir scores on the monthly goal observation scale of the SERAR (Del Valle and Bravo, 2007. The resultsindicate that, in general, children who are with their siblings obtain more benefits than children who arealone, especially in the dimensions of the residential setting. Nevertheless, when stays are too long, socialinteraction within the residence worsens in the groups of siblings. These results are discussed with regardto prior research and its practical implications.

  18. Association between bronchial asthma in atopic children and their number of siblings

    Directory of Open Access Journals (Sweden)

    Johan El Hakim Siregar

    2014-09-01

    Full Text Available Background The prevalence of asthma in children has increased in many countries. Environmental factors are believed to play an important role and an inverse relationship between number of siblings and atopic disorders has been observed. Objective To assess for an association between bronchial asthma in atopic children and their number of siblings. Methods A cross-sectional study was conducted from June to November 2010 in three elementary schools in Medan, North Sumatera. Trace cards from the Allergy-Immunology Indonesian Pediatric Association (IDAI Working Group and questionnaires on the clinical history of atopy were used to screen children with the risk of atopy. The International Study of Asthma and Allergies in Childhood (ISAAC questionnaire to screen for bronchial asthma was distributed to children aged 7-10 years with a history of asthma, allergic rhinitis or atopic dermatitis. Subjects were divided into two groups, those with <3 siblings and those with ≥3 siblings. Chi-square test was used to analyze differences in bronchial asthma prevalence between the two groups. Results Ninety-six subjects enrolled in the study, with 48 subjects per group. The prevalence of bronchial asthma was significantly higher in atopic children who had <3 siblings than in children with ≥3 siblings (73.5% and 26.5%, respectively; P=0.04. Conclusion Bronchial asthma was significantly more frequent in children with less than 3 siblings compared to those with 3 or more siblings. [Paediatr Indones. 2014;54:289-93.].

  19. Conjoined omphalopagus twins: a casereport

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    Sheila Yadira Gómez-Murillo

    2014-11-01

    Full Text Available Multiple pregnancies are 3% of the total. The most frequent are dizygotic females, however, a small group of them are of monozygotic conjoined twins in some anatomical area. This attracts the attention of physicians because of the rarity of the condition and the difficulties as well as the ethical dilemmas for their treatment. We report a case of male Siamese omphalopagus. They were separated surgically at seven weeks of age. One of them lived six months.

  20. Parenting and Psychopathology in Sibling Pairs

    Directory of Open Access Journals (Sweden)

    Jiri Modestin

    2008-06-01

    Full Text Available Background: The current study explored the relationship between parenting experience in childhood as a specific aspect of the non-shared environment and the amount of psychopathology in adulthood. Sampling and Methods: 27 same-sex sibling pairs were studied. In each pair, one proband was a psychiatric outpatient, the other proband a non-patient. All probands filled in the Parental Bonding Instrument (PBI and the Symptom Checklist-90-Revised (SCL-90-R. Results: The patients rated higher on practically all SCL-90-R scales whereas no significant differences were found with regard to the PBI ratings. With only one exception, there were no significant correlations between PBI and SCL-90-R ratings in the group of patients. In contrast, all SCL-90-R subscales correlated negatively with paternal care and half of them positively with paternal control in patients' healthy siblings. Conclusions: The degree of paternal care seems to be most closely related with lack of mental symptoms in psychiatric non-patients. In contrast, parenting does not seem to play a substantial role in patients, presenting with a higher degree of psychopathology. Obviously, environmental factors become less important, the more pronounced the pathology.

  1. Increased frequency of micronuclei in adults with a history of childhood sexual abuse: a discordant monozygotic twin study.

    Directory of Open Access Journals (Sweden)

    Timothy P York

    Full Text Available BACKGROUND: Childhood sexual abuse (CSA is a traumatic life event associated with an increased lifetime risk for psychopathology/morbidity. The long-term biological consequences of CSA-elicited stress on chromosomal stability in adults are unknown. The primary aim of this study was to determine if the rate of acquired chromosomal changes, measured using the cytokinesis-block micronucleus assay on stimulated peripheral blood lymphocytes, differs in adult female monozygotic twins discordant for CSA. METHODS: Monozygotic twin pairs discordant for CSA were identified from a larger population-based sample of female adult twins for whom the experience of CSA was assessed by self-report (51 individuals including a reference sample. Micronuclei (MN contain chromatin from structurally normal or abnormal chromosomes that are excluded from the daughter nuclei during cell division and serve as a biomarker to assess acquired chromosomal instability. RESULTS: Female twins exposed to CSA exhibited a 1.63-fold average increase in their frequency of MN compared to their nonexposed genetically identical cotwins (Paired t-test, t₁₆ = 2.65, P = 0.017. No additional effects of familial factors were detected after controlling for the effect of CSA exposure. A significant interaction between CSA history and age was observed, suggesting that the biological effects of CSA on MN formation may be cumulative. CONCLUSIONS: These data support a direct link between CSA exposure and MN formation measured in adults that is not attributable to genetic or environmental factors shared by siblings. Further research is warranted to understand the biological basis for the observed increase in acquired chromosomal findings in people exposed to CSA and to determine if acquired somatic chromosomal abnormalities/somatic clonal mosaicism might mediate the adult pathology associated with CSA.

  2. Genetic influence on bone mineral density in Korean twins and families: the healthy twin study.

    Science.gov (United States)

    Park, J-H; Song, Y-M; Sung, J; Lee, K; Kim, Y S; Park, Y S

    2012-04-01

    Bone mineral density (BMD), a representative marker of osteoporosis risk, is found to be highly heritable in this Korean study, which is very consistent with the findings in Western populations. This finding strongly supports that genetic factors are significant determinants of osteoporosis risk along with individual biological and behavioral factors. Although genetic factors are known to contribute significantly to variations in BMD in Western populations, such an association has not been fully evaluated in an Asian population. This study was conducted to determine the role of genetic factors on BMD in Korean population. The study participants were 2,728 men and women consisting of 497 monozygotic (MZ) twin pairs, 119 dizygotic (DZ) twin pairs, and 1,496 first-degree relatives from the Healthy Twin Study. BMD was measured using dual-energy X-ray absorptiometry. Quantitative genetic analysis based on a variance decomposition model was performed. Age and the measured covariates accounted for 17~61% of the variation in BMD, depending on the sites of measurement. After accounting for the covariate effects, the heritability of BMD at the whole body, thoracic and lumbar spine, whole ribs, whole pelvis, whole arms, and whole legs were 0.76, 0.72, 0.73, 0.71, 0.51, and 0.75, respectively. The pair-wise correlation of BMD was the highest within MZ twin pairs, followed by DZ twin pairs, sibling pairs, and parents-child pairs. Cross-trait correlation analysis revealed a positive genetic correlation between BMDs at different sites, ranging from 0.80 (arm and leg BMD) to 0.50 (pelvis and arm BMD). The high heritability of BMD in this Korean population similar to those found in Western populations and the significant common genetic basis between BMDs at different sites strongly supports a significant role of genetic determinants on the risk of osteoporosis.

  3. Twin anemia polycythemia sequence

    NARCIS (Netherlands)

    Slaghekke, Femke

    2014-01-01

    In this thesis we describe that Twin Anemia Polycythemia Sequence (TAPS) is a form of chronic feto-fetal transfusion in monochorionic (identical) twins based on a small amount of blood transfusion through very small anastomoses. For the antenatal diagnosis of TAPS, Middle Cerebral Artery – Peak Syst

  4. The Danish Twin Registry

    DEFF Research Database (Denmark)

    Skytthe, Axel; Ohm Kyvik, Kirsten; Vilstrup Holm, Niels

    2011-01-01

    Introduction: The Danish Twin Registry is a unique source for studies of genetic, familial and environmental factors on life events, health conditions and diseases. Content: More than 85,000 twin pairs born 1870-2008 in Denmark. Validity and coverage: Four main ascertainment methods have been emp...

  5. Twin anemia polycythemia sequence

    NARCIS (Netherlands)

    Slaghekke, Femke

    2014-01-01

    In this thesis we describe that Twin Anemia Polycythemia Sequence (TAPS) is a form of chronic feto-fetal transfusion in monochorionic (identical) twins based on a small amount of blood transfusion through very small anastomoses. For the antenatal diagnosis of TAPS, Middle Cerebral Artery – Peak

  6. Thoracopagus conjoined twin: an unusual presentation

    Directory of Open Access Journals (Sweden)

    Rajesh Kumari

    2014-02-01

    Full Text Available Conjoined twins are among rare clinical conditions observed by obstetricians. Due to rare incidence of this condition there is general lack of knowledge among obstetricians, especially at primary care level which leads to missed diagnosis during antenatal period. The management of this condition is complex especially in cases where the diagnosis is not known before onset of labour. A 30 - year old Hindu lady was referred to us from other hospital with diagnosis of twin pregnancy and prolonged second stage of labour. Clinical examination revealed findings of ruptured uterus and foetal head of one baby and feet of second baby were outside the introitus. Emergency laparotomy was done which revealed conjoined twins. This article report clinical course of a thoracopagus conjoined twin. The relevant literature is also reviewed. [Int J Reprod Contracept Obstet Gynecol 2014; 3(1.000: 245-247

  7. Twin studies: A unique epidemiological tool

    Directory of Open Access Journals (Sweden)

    Monalisha Sahu

    2016-01-01

    Full Text Available Twin studies are a special type of epidemiological studies designed to measure the contribution of genetics as opposed to the environment, to a given trait. Despite the facts that the classical twin studies are still being guided by assumptions made back in the 1920s and that the inherent limitation lies in the study design itself, the results suggested by earlier twin studies have often been confirmed by molecular genetic studies later. Use of twin registries and various innovative yet complex software packages such as the (SAS and their extensions (e.g., SAS PROC GENMOD and SAS PROC PHREG has increased the potential of this epidemiological tool toward contributing significantly to the field of genetics and other life sciences.

  8. Infantile Perineal Protrusion in Two Monochorionic Twins

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    Paola Cavicchioli

    2014-11-01

    Full Text Available Case Report - Two female monochorionic-monoamniotic twins showed the same kind of infantile perineal protrusion (IPP at birth. Lesions in both twins progressively healed until resolution in 6 weeks' time; none of the twins have manifested, till date, alvus disturbances. Discussion and Literature Review - A literature review numbers approximately 100 reports of IPP. This condition has been classically classified into three categories: congenital/familiar (i.e., female sex, positive parental history of IPP, acquired (mainly due to constipation, and associated with lichen sclerosus et atrophicus. Conclusions and Final Remarks - This case report describes, for the first time, the presence of IPP in monochorionic-monoamniotic twins, supporting the existence of hereditary/genetic factors in the developing of this condition.

  9. Inheritance of finger pattern types in MZ and DZ twins.

    Science.gov (United States)

    Karmakar, B; Malkin, I; Kobyliansky, E

    2011-08-01

    Digital patterns of a sample on twins were analyzed to estimate the resemblance between monozygotic (MZ) and dizygotic (DZ) twins and to evaluate the mode of inheritance by the use of maximum likelihood based variance decomposition analysis. MZ twin resemblance of finger pattern types appears to be more pronounced than in DZ twins, which suggests the presence of genetic factors in the forming of fingertip patterns. The most parsimonious model shows twin resemblance in count of all three basic finger patterns on 10 fingers. It has significant dominant genetic variance component across all fingers. In the general model, the dominant genetic variance component proportion is similar for all fingertips (about 60%) and the sibling environmental variance is significantly nonzero, but the proportion between additive and dominant variance components was different. Application of genetic model fitting technique of segregation analyses clearly shows mode of inheritance. A dominant genetic variance component or a specific genetic system modifies the phenotypic expression of the fingertip patterns. The present study provided evidence of strong genetic component in finger pattern types and seems more informative compared to the earlier traditional method of correlation analysis.

  10. Acoustic Emission of Deformation Twinning in Magnesium

    Directory of Open Access Journals (Sweden)

    Chengyang Mo

    2016-08-01

    Full Text Available The Acoustic Emission of deformation twinning in Magnesium is investigated in this article. Single crystal testing with combined full field deformation measurements, as well as polycrystalline testing inside the scanning electron microscope with simultaneous monitoring of texture evolution and twin nucleation were compared to testing at the laboratory scale with respect to recordings of Acoustic Emission activity. Single crystal testing revealed the formation of layered twin boundaries in areas of strain localization which was accompanied by distinct changes in the acoustic data. Testing inside the microscope directly showed twin nucleation, proliferation and growth as well as associated crystallographic reorientations. A post processing approach of the Acoustic Emission activity revealed the existence of a class of signals that appears in a strain range in which twinning is profuse, as validated by the in situ and ex situ microscopy observations. Features extracted from such activity were cross-correlated both with the available mechanical and microscopy data, as well as with the Acoustic Emission activity recorded at the laboratory scale for similarly prepared specimens. The overall approach demonstrates that the method of Acoustic Emission could provide real time volumetric information related to the activation of deformation twinning in Magnesium alloys, in spite of the complexity of the propagation phenomena, the possible activation of several deformation modes and the challenges posed by the sensing approach itself when applied in this type of materials evaluation approach.

  11. CALCULATION OF DISPLACEMENT FIELD AND DEFORMATIONS OF WEDGE SHAPED TWIN WITH THE HELP OF MESOSCOPIC DISLOCATIONAL MODEL

    Directory of Open Access Journals (Sweden)

    Y. V. Vasilevich

    2011-01-01

    Full Text Available Displacements and deformations of a wedge-shaped twin have been calculated with the help of mesoscopic dislocational model. It has been shown that deformations are localized at twin boundaries and twin top and also at some limited areas which are rather far from the twin

  12. The contribution of twins to the study of cognitive ageing and dementia: the Older Australian Twins Study.

    Science.gov (United States)

    Sachdev, Perminder S; Lee, Teresa; Wen, Wei; Ames, David; Batouli, Amir H; Bowden, Jocelyn; Brodaty, Henry; Chong, Elizabeth; Crawford, John; Kang, Kristan; Mather, Karen; Lammel, Andrea; Slavin, Melissa J; Thalamuthu, Anbupalam; Trollor, Julian; Wright, Margie J

    2013-12-01

    The Older Australian Twins Study (OATS) is a major longitudinal study of twins, aged ≥ 65 years, to investigate genetic and environmental factors and their interactions in healthy brain ageing and neurocognitive disorders. The study collects psychiatric, neuropsychological, cardiovascular, metabolic, biochemical, neuroimaging, genomic and proteomic data, with two-yearly assessments, and is currently in its third wave. The initial cohort comprises 623 individuals (161 monozygotic and 124 dizygotic twin pairs; 1 MZ triplets; 27 single twins and 23 non-twin siblings), of whom 426 have had wave 2 assessment. A number of salient findings have emerged thus far which assist in the understanding of genetic contributions to cognitive functions such as processing speed, executive ability and episodic memory, and which support the brain reserve hypothesis. The heritability of brain structures, both cortical and subcortical, brain spectroscopic metabolites and markers of small vessel disease, such as lacunar infarction and white matter hyperintensities, have been examined and can inform future genetic investigations. Work on amyloid imaging and functional magnetic resonance imaging is proceeding and epigenetic studies are progressing. This internationally important study has the potential to inform research into cognitive ageing in the future, and offers an excellent resource for collaborative work.

  13. The self-esteem and anxiety of children with and without mentally retarded siblings

    Directory of Open Access Journals (Sweden)

    Fatma Saban

    2013-01-01

    Full Text Available Background: The study was carried out with the aim of determining the factors affecting and to evaluate anxiety situations and self-esteem of children with and without mentally retarded siblings. Materials and Methods: The sampling included 227 healthy children: 108 of them have mental retarded sibling and 119 of them do not have mental retarded sibling. The context of this study consisted of 15-18 year of age healthy children with mentally retarded siblings and 15-18 year of aged healthy children having at least one sibling between the dates February 15 st and June 26 st 2010. Personal Information Form, Rosenberg Self-Esteem Scale and Trait Anxiety Scale were used. Results: It was found out that trait anxiety of 17-18 aged of children with mental retarded sibling (47.04 ± 7.3 was higher than that of the children without mental retarded siblings (44.05 ± 11.23 (P 0.05. Trait anxiety score averages of children with mentally retarded sibling and experience some difficulties due to his or her siblings′s handicap (47.00 ± 7.76 were found higher than those of those of the children without any problem with the environment (42.61 ± 7.48 (P < 0.05. Conclusion: Although the average score of trait anxiety and self-esteem in both groups were not significant different, score of trait anxiety for children with mentally disabled siblings was higher in comparison. It was concluded that anxiety of children with and without mentally retarded siblings increased as self-esteem of these children decreased.

  14. Sibling configuration predicts individual and descendant socioeconomic success in a modern post-industrial society.

    Directory of Open Access Journals (Sweden)

    David W Lawson

    Full Text Available Growing up with many siblings, at least in the context of modern post-industrial low fertility, low mortality societies, is predictive of relatively poor performance on school tests in childhood, lower levels of educational attainment, and lower income throughout adulthood. Recent studies further indicate these relationships hold across generations, so that the descendants of those who grow up with many siblings are also at an apparent socioeconomic disadvantage. In this paper we add to this literature by considering whether such relationships interact with the sex and relative age of siblings. To do this we utilise a unique Swedish multigenerational birth cohort study that provides sibling configuration data on over 10,000 individuals born in 1915-1929, plus all their direct genetic descendants to the present day. Adjusting for parental and birth characteristics, we find that the 'socioeconomic cost' of growing up in a large family is independent of both the sex of siblings and the sex of the individual. However, growing up with several older as opposed to several younger siblings is predictive of relatively poor performance on school tests and a lower likelihood of progression to tertiary education. This later-born disadvantage also holds across generations, with the children of those with many older siblings achieving lower levels of educational attainment. Despite these differences, we find that while individual and descendant income is negatively related to the number of siblings, it is not influenced by the relative age of siblings. Thus, our findings imply that the educational disadvantage of later-born children, demonstrated here and in numerous other studies, does not necessarily translate into reduced earnings in adulthood. We discuss potential explanations for this pattern of results, and consider some important directions for future research into sibling configuration and wellbeing in modern societies.

  15. A twin and molecular genetics study of sleep paralysis and associated factors.

    Science.gov (United States)

    Denis, Dan; French, Christopher C; Rowe, Richard; Zavos, Helena M S; Nolan, Patrick M; Parsons, Michael J; Gregory, Alice M

    2015-08-01

    Sleep paralysis is a relatively common but under-researched phenomenon. In this paper we examine prevalence in a UK sample and associations with candidate risk factors. This is the first study to investigate the heritability of sleep paralysis in a twin sample and to explore genetic associations between sleep paralysis and a number of circadian expressed single nucleotide polymorphisms. Analyses are based on data from the Genesis1219 twin/sibling study, a community sample of twins/siblings from England and Wales. In total, data from 862 participants aged 22-32 years (34% male) were used in the study. This sample consisted of monozygotic and dizygotic twins and siblings. It was found that self-reports of general sleep quality, anxiety symptoms and exposure to threatening events were all associated independently with sleep paralysis. There was moderate genetic influence on sleep paralysis (53%). Polymorphisms in the PER2 gene were associated with sleep paralysis in additive and dominant models of inheritance-although significance was not reached once a Bonferroni correction was applied. It is concluded that factors associated with disrupted sleep cycles appear to be associated with sleep paralysis. In this sample of young adults, sleep paralysis was moderately heritable. Future work should examine specific polymorphisms associated with differences in circadian rhythms and sleep homeostasis further in association with sleep paralysis.

  16. Feature Discretization for Individuality Representation in Twins Handwritten Identification

    Directory of Open Access Journals (Sweden)

    Bayan O. Mohammed

    2011-01-01

    Full Text Available Problem statement: The study on twins is an important form of study in the forensic and biometrics field as twins share similar genetic traits. Handwriting is one of the common types of forensic evidence. Differentiating the similarities of writing of a pair of twins is critical in establishing the reliability of handwriting identification. Writing style can be used as biometric features in authenticating individual uniqueness where these unique features can be used to identify the writer, including between a pair of twins. Existing works in Writer Identification concentrate on feature extraction and the classification task in order to identify authorship. The high similarity in a pair of twins’ handwriting may degrade classification performance. There should be some standards to represent these unique features before entering into the classification task which is with the use of discretization technique. Approach: We proposed a new framework for writer identification in terms of identifying twins' handwriting and showed the effect of discretization process on handwriting samples of a pair of twins in order to obtain individual identification. Results: An experiment has been done at the Sulaimania University in Iraq with fourteen pairs of identical twins where each twin provides 4 samples of handwriting for the purpose of data collecting. These samples were implemented in this research making a comparison between the new proposed framework and classic framework. Conclusion: Our experimental results showed that with new framework identification of handwriting of a pair of twins can be improved through the discretization process.

  17. A Case of Monozygotic Twins: The Value of Discordant Monozygotic Twins in Goldenhar Syndrome—OMIM%164210

    Directory of Open Access Journals (Sweden)

    K. N. Venkateshwara Prasad

    2013-01-01

    Full Text Available Goldenhar syndrome is a rare developmental disorder characterised by hemifacial microsomia, epibulbar tumours, ear malformation, and vertebral anomalies. As monozygotic (MZ twins are believed to be genetically identical, discordance for disease phenotype between MZ twins varies with craniofacial anomalies, cardiac, vertebral, and central nervous system defects sporadically. We report a case of monozygotic female twins discordant for Goldenhar syndrome with hemifacial microsomia and the dysplasia of auricular pinna.

  18. The solar siblings in the Gaia era

    Science.gov (United States)

    Martínez-Barbosa, C. A.; Brown, A. G. A.; Portegies Zwart, S.

    2014-07-01

    We perform realistic simulations of the Sun's birth cluster in order to predict the current distribution of solar siblings in the Galaxy. We study the possibility of finding the solar siblings in the Gaia catalogue by using only positional and kinematic information. We find that the number of solar siblings predicted to be observed by Gaia will be around 100 in the most optimistic case, and that a phase space only search in the Gaia catalogue will be extremely difficult. It is therefore mandatory to combine the chemical tagging technique with phase space selection criteria in order to have any hope of finding the solar siblings.

  19. The solar siblings in the Gaia era

    CERN Document Server

    Martínez-Barbosa, C A; Zwart, S Portegies

    2015-01-01

    We perform realistic simulations of the Sun's birth cluster in order to predict the current distribution of solar siblings in the Galaxy. We study the possibility of finding the solar siblings in the Gaia catalogue by using only positional and kinematic information. We find that the number of solar siblings predicted to be observed by Gaia will be around 100 in the most optimistic case, and that a phase space only search in the Gaia catalogue will be extremely difficult. It is therefore mandatory to combine the chemical tagging technique with phase space selection criteria in order to have any hope of finding the solar siblings.

  20. Relational Aggression in Adolescents' Sibling Relationships: Links to Sibling and Parent-Adolescent Relationship Quality

    Science.gov (United States)

    Updegraff, Kimberly A.; Thayer, Shawna M.; Whiteman, Shawn D.; Denning, Donna J.; McHale, Susan M.

    2005-01-01

    This study examined the links between sibling relational aggression and other sibling relationship qualities (i.e., intimacy, negativity, and temporal involvement) and broader parenting dynamics. Participants included 185 adolescent sibling pairs and their mothers and fathers. Data were gathered during home interviews and a series of nightly phone…

  1. Laying the ghost of twin paradox

    Directory of Open Access Journals (Sweden)

    Popović Marko

    2009-01-01

    Full Text Available Someone's true age is not written in his ID, but in his biomarkers. Aging process is not caused by time passing, but by thermodynamically laws. Entropy, extent of metabolic reaction, and temperature are Lorentz invariant, so these facts make twin paradox impossible because there is no way for one twin to age slower than the other even if the time in his frame is dilated. Entropy is the function of state, not time. So as much as standard thermodynamics concerns, the path between two points in space is equivalent to the path between two states. Whether the point B is reached by moving faster using the longer way (with time dilatation, or slower by using shortcut (without time dilatation, the state of the system after completing the road should be the same. This is supported by the fact that when two twins reach the same space-time point (point B in which the state parameters are the same. If we use entropy as an age parameter, then both twins have the same entropy value and are exactly the same biological age. Therefore, the twin paradox is a logical mistake based on wrong first premise. Bergson symmetry is not necessary any more to explain the impossibility of twin paradox.

  2. Imperfect twinning: a clinical and ethical dilemma

    Directory of Open Access Journals (Sweden)

    Daniela Denardin

    2013-09-01

    Full Text Available OBJECTIVE To review the history, epidemiology, etiology, gestational aspects, diagnosis and prognosis of imperfect twinning. DATA SOURCES Scientific articles were searched in PubMed, SciELO and Lilacs databases, using the descriptors "conjoined twins", "multiple pregnancy", "ultrasound", "magnetic resonance imaging" and "prognosis". The research was not delimited to a specific period of time and was supplemented with bibliographic data from books. DATA SYNTHESIS: The description of conjoined twins is legendary. The estimated frequency is 1/45,000-200,000 births. These twins are monozygotic, monochorionic and usually monoamniotic. They can be classified by the most prominent fusion site, by the symmetry between the conjoined twins or by the sharing structure. The diagnosis can be performed in the prenatal period or after birth by different techniques, such as ultrasound, magnetic resonance imaging and echocardiography. These tests are of paramount importance for understanding the anatomy of both fetuses/children, as well as for prognosis and surgical plan determination. CONCLUSIONS Although imperfect twinning is a rare condition, the prenatal diagnosis is very important in order to evaluate the fusion site and its complexity. Hence, the evaluation of these children should be multidisciplinary, involving mainly obstetricians, pediatricians and pediatric surgeons. However, some decisions may constitute real ethical dilemmas, in which different points should be discussed and analyzed with the health team and the family.

  3. Presentation of hypohidrotic ectodermal dysplasia in two siblings

    Directory of Open Access Journals (Sweden)

    Uday Ginjupally

    2015-01-01

    Full Text Available Ectodermal dysplasias are a large hereditary group of disorders which are usually manifested as X-linked recessive disorders and have a full expression in males, whereas females show little to no signs of the disorder. The two most common types of ectodermal dysplasias are hypohidrotic ectodermal dysplasia (Christ-Siemens-Touraine syndrome and hidrotic ectodermal dysplasia (Clouston syndrome. Hypohidrotic ectodermal dysplasia is characterized by hypodontia, hypotrichosis, and hypohidrosis. Here, we present two female sibling cases of hypohidrotic ectodermal dysplasia.

  4. Juvenile greylag geese (Anser anser discriminate between individual siblings.

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    Isabella B R Scheiber

    Full Text Available Social species that maintain individualised relationships with certain others despite continuous changes in age, reproductive status and dominance rank between group members ought to be capable of individual recognition. Tests of "true" individual recognition, where an individual recognises unique features of another, are rare, however. Often kinship and/or familiarity suffice to explain dyadic interactions. The complex relationships within a greylag goose flock suggest that they should be able to recognise individuals irrespective of familiarity or kinship. We tested whether six-week-old hand-raised greylags can discriminate between two of their siblings. We developed a new experimental protocol, in which geese were trained to associate social siblings with geometrical symbols. Subsequently, focals were presented with two geometrical symbols in the presence of a sibling associated with one of the symbols. Significant choice of the geometrical symbol associated with the target present indicated that focals were able to distinguish between individual targets. Greylag goslings successfully learned this association-discrimination task, regardless of genetic relatedness or sex of the sibling targets. Social relationships within a goose flock thus may indeed be based on recognition of unique features of individual conspecifics.

  5. Prosocial competencies among adolescent siblings of the physically disabled

    Directory of Open Access Journals (Sweden)

    Lidia Perenc

    2015-09-01

    Full Text Available Background The current study examined possible prosocial benefits of having a disabled sibling. Until now research has mainly focused on the negative effects of having a sibling with a disability. We hypothesized that regular and frequent interactions with a disabled person should result in an increase of positive attitude and empathy toward other people who are in a disadvantageous situation. Participants and procedure A sample of 208 students from public secondary schools (middle and high schools completed the Polish version of the Prosocial Tendencies Measure (PTM in order to assess the tendencies to prosocial behaviors in different conditions. Participants were between 13 and 18 years old. Ninety-six adolescents had a disabled sibling (group T and 112 constituted the control group (group C. Results Results showed that group T generally scored higher than group C in the number of helping behaviors. Furthermore, girls scored higher than boys in anonymous prosocial behaviors. The older adolescents are more inclined to use helping behaviors both in anonymous and compliant situations than their younger colleagues. Conclusions Presence of disabled children in a family context may facilitate prosocial behavior in their non-disabled siblings. Older participants less frequently described themselves as prosocial in public situations. In contrast, younger adolescents reported weaker prosocial tendencies in anonymous and compliant situations. The effect of gender on prosocial tendencies was significant for public prosocial behavior, with a higher level achieved by males in this domain. Data analysis also showed significantly greater emotional and altruistic tendencies in females than in males.

  6. Infant siblings and the investigation of autism risk factors

    Directory of Open Access Journals (Sweden)

    Newschaffer Craig J

    2012-04-01

    Full Text Available Abstract Infant sibling studies have been at the vanguard of autism spectrum disorders (ASD research over the past decade, providing important new knowledge about the earliest emerging signs of ASD and expanding our understanding of the developmental course of this complex disorder. Studies focused on siblings of children with ASD also have unrealized potential for contributing to ASD etiologic research. Moving targeted time of enrollment back from infancy toward conception creates tremendous opportunities for optimally studying risk factors and risk biomarkers during the pre-, peri- and neonatal periods. By doing so, a traditional sibling study, which already incorporates close developmental follow-up of at-risk infants through the third year of life, is essentially reconfigured as an enriched-risk pregnancy cohort study. This review considers the enriched-risk pregnancy cohort approach of studying infant siblings in the context of current thinking on ASD etiologic mechanisms. It then discusses the key features of this approach and provides a description of the design and implementation strategy of one major ASD enriched-risk pregnancy cohort study: the Early Autism Risk Longitudinal Investigation (EARLI.

  7. Schizophrenia and subsequent neighborhood deprivation: revisiting the social drift hypothesis using population, twin and molecular genetic data

    Science.gov (United States)

    Sariaslan, A; Fazel, S; D'Onofrio, B M; Långström, N; Larsson, H; Bergen, S E; Kuja-Halkola, R; Lichtenstein, P

    2016-01-01

    Neighborhood influences in the etiology of schizophrenia have been emphasized in a number of systematic reviews, but causality remains uncertain. To test the social drift hypothesis, we used three complementary genetically informed Swedish cohorts. First, we used nationwide Swedish data on approximately 760 000 full- and half-sibling pairs born between 1951 and 1974 and quantitative genetic models to study genetic and environmental influences on the overlap between schizophrenia in young adulthood and subsequent residence in socioeconomically deprived neighborhoods. Schizophrenia diagnoses were ascertained using the National Patient Registry. Second, we tested the overlap between childhood psychotic experiences and neighborhood deprivation in early adulthood in the longitudinal Twin Study of Child and Adolescent Development (TCHAD; n=2960). Third, we investigated to what extent polygenic risk scores for schizophrenia predicted residence in deprived neighborhoods during late adulthood using the TwinGene sample (n=6796). Sibling data suggested that living in deprived neighborhoods was substantially heritable; 65% (95% confidence interval (95% CI): 60–71%) of the variance was attributed to genetic influences. Although the correlation between schizophrenia and neighborhood deprivation was moderate in magnitude (r=0.22; 95% CI: 0.20–0.24), it was entirely explained by genetic influences. We replicated these findings in the TCHAD sample. Moreover, the association between polygenic risk for schizophrenia and neighborhood deprivation was statistically significant (R2=0.15%, P=0.002). Our findings are primarily consistent with a genetic selection interpretation where genetic liability for schizophrenia also predicts subsequent residence in socioeconomically deprived neighborhoods. Previous studies may have overemphasized the relative importance of environmental influences in the social drift of schizophrenia patients. Clinical and policy interventions will therefore

  8. SUSY Meets Her Twin

    CERN Document Server

    Katz, Andrey; Pokorski, Stefan; Redigolo, Diego; Ziegler, Robert

    2016-01-01

    We investigate the general structure of mirror symmetry breaking in the Twin Higgs scenario. We show, using the IR effective theory, that a significant gain in fine tuning can be achieved if the symmetry is broken hardly. We emphasize that weakly coupled UV completions can naturally accommodate this scenario. We analyze SUSY UV completions and present a simple Twin SUSY model with a tuning of around 10% and colored superpartners as heavy as 2 TeV. The collider signatures of general Twin SUSY models are discussed with a focus on the extended Higgs sectors.

  9. SUSY Meets Her Twin

    CERN Document Server

    Katz, Andrey; Pokorski, Stefan; Redigolo, Diego; Ziegler, Robert

    2017-01-01

    We investigate the general structure of mirror symmetry breaking in the Twin Higgs scenario. We show, using the IR effective theory, that a significant gain in fine tuning can be achieved if the symmetry is broken hardly. We emphasize that weakly coupled UV completions can naturally accommodate this scenario. We analyze SUSY UV completions and present a simple Twin SUSY model with a tuning of around 10% and colored superpartners as heavy as 2 TeV. The collider signatures of general Twin SUSY models are discussed with a focus on the extended Higgs sectors.

  10. SUSY Meets Her Twin

    CERN Document Server

    Katz, Andrey; Pokorski, Stefan; Redigolo, Diego; Ziegler, Robert

    2017-01-31

    We investigate the general structure of mirror symmetry breaking in the Twin Higgs scenario. We show, using the IR effective theory, that a significant gain in fine tuning can be achieved if the symmetry is broken hardly. We emphasize that weakly coupled UV completions can naturally accommodate this scenario. We analyze SUSY UV completions and present a simple Twin SUSY model with a tuning of around 10% and colored superpartners as heavy as 2 TeV. The collider signatures of general Twin SUSY models are discussed with a focus on the extended Higgs sectors.

  11. Twin Crises in Turkey: A Comparison of Currency Crisis Models

    Directory of Open Access Journals (Sweden)

    Hakan Yilmazkuday

    2008-06-01

    Full Text Available This paper analyzes the twin crises in Turkey experienced in 2000 and 2001. After a detailed survey of currency crisis models, together with a brief descriptive overview of the crises in Turkey, the similarities among the twin crises in Turkey and the models that have been developed to explain preceding crises in the world are investigated. It is found that the Turkish twin crises cannot be explained by using any individual generation of models, namely first generation models, second generation models or third generation models. Instead, a combination of these models is more appropriate to explain the details of the twin crises.

  12. 3D Evaluation of Palatal Rugae in Identical Twins

    Directory of Open Access Journals (Sweden)

    Emiliya Taneva

    2017-01-01

    Full Text Available The study of identical twins can point out potential limitations in biometrics and forensic odontology. This case report presents three-dimensional (3D palatal rugae analysis in monozygotic twins utilizing digital models obtained directly by scanning the maxillary dental arch with the iTero® intraoral digital scanner. The results show that the rugae patterns contain related but not identical features between the pair of identical twins. Dental study models taken on a regular basis for diagnosis and treatment planning in dentistry include the palatal rugae, which could be valuable to forensics in identical twin identification cases.

  13. Class - III malocclusion: Genetics or environment? A twins study

    Directory of Open Access Journals (Sweden)

    Jena A

    2005-03-01

    Full Text Available Etiology of class-III malocclusion is generally believed to be genetic. A wide range of environmental factors have been suggested as contributing factors for the development of class-III malocclusion. Twin study is one of the most effective methods available for investigating genetically determined variables of malocclusion. Discordancy for class-III malocclusion is a frequent finding in dizygotic twins. However, class-III malocclusion discordancy in monozygotic twins is a rare finding. The purpose of this study of monozygotic twins is to assess the genetic and environmental components of variation within the cranio-dento-facial complex.

  14. Successful skin homografting from an identical twin in a severely burned patient.

    Science.gov (United States)

    Turk, Emin; Karagulle, Erdal; Turan, Hale; Oguz, Hakan; Abali, Ebru Sakallioglu; Ozcay, Necdet; Moray, Gokhan; Haberal, Mehmet

    2014-01-01

    Flame burns are a serious condition and usually have high morbidity and mortality because they affect large areas of the body surface as well as the lungs. In these patients, it is especially difficult to find healthy skin for grafting if they have more than 70% third-degree burns. Repeated autografting or synthetic wound care materials are the only treatment options to cover burned areas. Partial-thickness skin grafting from the patient's identical twin sibling may be an alternative treatment option, if possible. Here, we report a patient with severe flame injury treated with skin from his identical twin. The patient had third-degree burns covering 70% of his body surface. Initial treatment consisted of fluid and electrolyte replacement, daily wound care, and surgical debridements, as well as nutritional support. After initial treatment, we performed a successful skin grafting from his identical twin. Skin grafting between identical twins might be an alternate method for severely burned patients.

  15. Childhood Ataxia with Cerebral Hypomyelination (CACH syndrome: A study of three siblings

    Directory of Open Access Journals (Sweden)

    Vaidya Sachin

    2004-07-01

    Full Text Available We report a family of three siblings with Childhood Ataxia with Cerebral Hypomyelination. All the siblings presented with early onset cerebellar ataxia beginning around five years of age with mild mental retardation. MRI showed diffuse white matter signal changes in all three patients with cerebellar atrophy while the spectroscopy was abnormal only in the eldest who was the most severely affected. The cases are reported for their rarity as well as for an opportunity of observing this uncommon disease in its stages of evolution in three siblings.

  16. Striatal necrosis in type 1 glutaric aciduria: Different stages in two siblings

    Directory of Open Access Journals (Sweden)

    Anitha Sen

    2011-01-01

    Full Text Available Two siblings born of a consanguineous marriage with history of neurologic deterioration were imaged. Imaging features are classical of glutaric aciduria type 1 (GA-1, acute (striatal necrosis stage in younger sibling, and chronic stage in older sibling. GA-1 is an autosomal recessive disease with typical imaging features. Greater awareness about this condition among clinicians and radiologists is essential for early diagnosis and prevention of its catastrophic consequences. Striatal necrosis with stroke-like signal intensity on imaging correlates with clinical stage of patients.

  17. Restrictive Dermopathy: Report of Two Siblings

    Directory of Open Access Journals (Sweden)

    Chih-Sheng Lu

    2013-06-01

    Full Text Available Restrictive dermopathy (RD is a rare and lethal autosomal recessive syndrome characterized by very tight, thin, and easily eroded skin and contracture of joints. We present two siblings in a family. Case 1, a female neonate, showed mild characteristic presentations of RD and survived for 16 days, and Case 2, a male neonate, was stillborn with typical severe features of RD. His skin biopsy showed typical histological findings, and genetic study revealed a homozygous nonsense mutation on the exon 6 of zinc metalloproteinase STE24 (ZMPSTE24. The exact pathogenic mechanism of RD remains poorly understood. The most recent studies on mutations in lamin A and/or ZMPSTE24 have shed some light on the pathophysiology of RD and may help direct the development of future therapeutic approaches.

  18. Review of studies of support for siblings with developmental disabilities

    OpenAIRE

    2012-01-01

    The purpose of this paper is to review the study on siblings of disabilities, and investigate siblings'experience and the trend in supports for them. As a result, two important factors are considered, 1) the role as siblings of people with disabilities were changed with the times, from role as caretaker about people with disabilities into role as siblings who have their own concern and to be supported. 2) siblings have unusual concerns and opportunities, however, siblings must care for their ...

  19. Sibling Dependence, Uncertainty and Education

    DEFF Research Database (Denmark)

    Lilleør, Helene Bie

    in the educational decision, which is consistent with a human capital portfolio theory of risk diversification and which cannot be explained by sibling rivalry over scarce resources for credit constrained households. The paper thus provides a complementary explanation to why enrolment rates in developing countries...... future agricultural employment. Given this dichtomy, the question is then: Does future income uncertainty influence the joint educational choice made by parents on behalf of their children and is it possible to test this on simple cross-sectional data? I extend a simple human capital portfolio model...

  20. Differences in Age between Siblings

    DEFF Research Database (Denmark)

    Høgsbro Lading, Åse

    Themain assumption here is that people re-enact in their relationship with others not only what they experienced in parent-child relationship but also in their original relationships with siblings, relationships that are so significant that they stand on their own. While the dyadic analytic...... relationship tends to bring out a parent-child transference, the transference relationships in the group are familial ones, the transference is horizontal. The group, offering the possibility of many transferential, “sibling” relationships, is the best therapeutic setting in which to deal with this issue....

  1. Intellectual similarity of virtual twin pairs: Developmental trends.

    Science.gov (United States)

    Segal, Nancy L; McGuire, Shirley A; Havlena, June; Gill, Patricia; Hershberger, Scott L

    2007-05-01

    Virtual twins (VTs) are same-age unrelated siblings reared together from infancy who replicate twinship, but without the genetic relatedness. A 2005 report from the ongoing Fullerton Virtual Twin Study found an IQ intraclass correlation of .26 (p < .01, n = 113 pairs) and a within-pair difference of 13.22 IQ points. The average age of VTs in that study was 8.10 years (SD = 8.56, range: 4.01-54.84 years). An opportunity to retest members of 43 VT pairs, 1.70-8.96 years after their time 1 assessment, allowed additional analyses of genetic and environmental influences underlying general intellectual development. A decrease in the VT IQ correlation and an increase in the within-pair difference were indicated, consistent with increasing genetic and/or non-shared environmental influences and decreasing shared environmental influence on general intellectual development throughout childhood.

  2. Craniofacial anomalies in twins.

    Science.gov (United States)

    Keusch, C F; Mulliken, J B; Kaplan, L C

    1991-01-01

    Studies of twins provide insight into the relative contribution of genetic and environmental factors in the causality of structural anomalies. Thirty-five affected twin pairs were identified from a group of 1114 patients with congenital craniofacial deformities evaluated from 1972 to 1989. Forty-three of these 70 twins exhibited one or more craniofacial anomalies; these were analyzed for dysmorphic characteristics, zygosity, concordance, and family history. The anomalies were categorized into two groups: malformations and deformations. The malformations (n = 36) included hemifacial microsomia (n = 10), cleft lip and palate (n = 8), cleft palate (n = 4), rare facial cleft (n = 2), craniosynostosis (n = 2), Binder syndrome (n = 2), Treacher Collins syndrome (n = 2), craniopagus (n = 2), CHARGE association (n = 1), frontonasal dysplasia (n = 2), and constricted ears (n = 1). The deformations (n = 7) included plagiocephaly (n = 5), hemifacial hypoplasia (n = 1), and micrognathia (n = 1). Twenty-one monozygotic and 14 dizygotic twin pairs were identified. The concordance rate was 33 percent for monozygotic twins and 7 percent for dizygotic twins.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Spontaneous Live Twin Tubal Ectopic Pregnancy: A Case Report

    Directory of Open Access Journals (Sweden)

    R Benn

    2016-02-01

    Full Text Available We report the case of a 29-year old G3P1+1 woman with a spontaneously conceived live twin tubal ectopic pregnancy. Her history was significant for infertility for 11 years after an induced abortion. Pelvic ultrasound scan showed live twin ectopic pregnancy and a partial salpingectomy was done.

  4. Siblings of Handicapped Children: A Review.

    Science.gov (United States)

    Lobato, Debra

    1983-01-01

    Research is critically reviewed and evaluated to determine if the presence of a handicapped child in a family uniquely affects the nonhandicapped siblings and to identify factors mediating the nature and power of those effects. In addition, projects involving sibling therapy, education, and training are described. (Author/CL)

  5. The Female Experience of Sibling Incest.

    Science.gov (United States)

    Canavan, Margaret M.; And Others

    1992-01-01

    Calls occurrence of sibling incest underrecognized. Presents four cases of females who experienced sibling incest to illustrate problem areas, including issues of enforced secrecy, interpersonal power differentials, influences on sexual development, individual after effects, disturbances in family dynamics, and gender-based differences in…

  6. Adult Siblings Consider the Future: Emergent Themes

    Science.gov (United States)

    Davys, Deborah; Mitchell, Duncan; Haigh, Carol

    2016-01-01

    Background: This study aimed to explore the perceptions of adult siblings regarding a future care role and compare with perceived parental wishes as family often provide a key support role in the lives of people who have an intellectual disability. Materials and Method: Semi-structured interviews were undertaken with 15 adult siblings and an…

  7. If -Then Contingencies in Children's Sibling Conflicts

    Science.gov (United States)

    Perlman, Michal; Ross, Hildy S.

    2005-01-01

    Two-step (if -then) behavioral contingencies in the naturally occurring conflicts of 2- and 4-year-old siblings were identified and described. Children's crying, compliance, ignoring, opposition, power, and reasoning strategies were examined to determine how they were used immediately following opposition, power, and reasoning from siblings and…

  8. Caregiving and Sibling Relationships: Challenges and Opportunities

    Science.gov (United States)

    ... when one sibling is in denial over a parent’s condition. Adult children who seem unable to accept the reality of ... and needed. Keep family members informed regarding a parent’s condition. Be realistic in your expectations. Allow siblings to help in ways they are ...

  9. Interaction between Siblings in Primetime Television Families.

    Science.gov (United States)

    Larson, Mary S.

    1989-01-01

    Analyzes three primetime family sitcoms in order to describe the nature of sibling interaction in television families. Research on television families is examined, and questions are raised concerning the value of television sibling images as role models for real people, and the effects of these models on family and peer relationships. (27…

  10. Sibling Family Practices: Guidelines for Healthy Boundaries

    Science.gov (United States)

    Johnson, Toni Cavanagh; Huang, Bevan Emma; Simpson, Pippa M.

    2009-01-01

    A questionnaire was given to 500 mental health and child welfare professionals asking for maximum acceptable ages for siblings to engage jointly in certain family practices related to hygiene, affection, and privacy. A large proportion of respondents felt it was never acceptable for siblings to take showers together (40%), kiss on the mouth (37%),…

  11. Are Sibling Relationships Protective? A Longitudinal Study

    Science.gov (United States)

    Gass, Krista; Jenkins, Jennifer; Dunn, Judy

    2007-01-01

    Background: Although the protective effects of familial and parental support have been studied extensively in the child psychopathology literature, few studies have explored the protective quality of positive sibling relationships. Methods: A two-wave longitudinal design was used to examine the protective effect of positive sibling relationships…

  12. Twin delivery: how should the second twin be delivered?

    Science.gov (United States)

    Olofsson, P; Rydhström, H

    1985-11-01

    In a series of 803 pairs of twins born between 1973 and 1982, 0.33% of second twins were delivered by cesarean section after vaginal delivery of the first twin. During the last year the frequency has increased to 7%, calling attention to the problem of declining obstetric skills and experience. This has caused us to update the routines of intrapartum management of twin gestations. In the present program only commonly available obstetric techniques are used. The potentially hazardous twin delivery is excluded from a trial of vaginal delivery. Hopefully, the program will help other obstetricians to decide in favor of vaginal delivery in selected twin gestations.

  13. Mucopolysaccharidoses type IV A (Morquio syndrome: A case series of three siblings

    Directory of Open Access Journals (Sweden)

    P Rekka

    2012-01-01

    Full Text Available Mucopolysaccharidoses (MPS are a family of inherited metabolic diseases that results from the deficiency of lysosomal enzymes involved in the degradation of the glycosaminoglycans (mucopolysaccharides. Despite the well-documented oral and dental findings of MPS type IV, there is not much literature documented about the incidence of this disorder among siblings in the same family. This report outlines the clinical and radiographic findings found in three siblings with Morquio syndrome.

  14. STUDY OF OBSTETRIC COMPLICATIONS & OUTCOME OF TWIN PREGNANCY

    Directory of Open Access Journals (Sweden)

    Swati

    2014-10-01

    Full Text Available : INTRODUCTION: Twin pregnancy is a rare phenomenon and significantly related to increased maternal & fetal morbidity and mortality as compared to singleton pregnancy. It is important that every physician must know the complications related to twin pregnancy and how to manage these complications. DESIGN: Prospective observational study AIMS AND OBJECTIVE: (1 To study incidence of various obstetric complications in twin pregnancy (2 To study outcome of twin pregnancy in terms of average duration of gestation, mode of delivery & neonatal outcome. METHODS: 59 Patients with sonographically confirmed twin pregnancy attending ante-natal care outpatient department (ANC OPD & labor room at a tertiary care hospital in our Unit in specified period of 18 months as mentioned above were enrolled in this study and followed till delivery and thereafter in the neonatal period. RESULTS: In this study twin pregnancies were slightly more in multigravida. The rate of preterm delivery was 77.9%.PIH & Anaemia was more common in primigravida. Monochorionic twins had more complications than dichorionic twins. NICU admission rate in this study was 23.6%, perinatal mortality rate was 16.9% and neonatal mortality rate was 12.2%. CONCLUSION: Twinning in pregnancy is a high risk factor which can cause various maternal as well fetal complications. Prompt ANC care and timely intervention is required to avoid these complications.

  15. Heritability and Genome-Wide Association Studies for Hair Color in a Dutch Twin Family Based Sample

    Directory of Open Access Journals (Sweden)

    Bochao Danae Lin

    2015-07-01

    Full Text Available Hair color is one of the most visible and heritable traits in humans. Here, we estimated heritability by structural equation modeling (N = 20,142, and performed a genome wide association (GWA analysis (N = 7091 and a GCTA study (N = 3340 on hair color within a large cohort of twins, their parents and siblings from the Netherlands Twin Register (NTR. Self-reported hair color was analyzed as five binary phenotypes, namely “blond versus non-blond”, “red versus non-red”, “brown versus non-brown”, “black versus non-black”, and “light versus dark”. The broad-sense heritability of hair color was estimated between 73% and 99% and the genetic component included non-additive genetic variance. Assortative mating for hair color was significant, except for red and black hair color. From GCTA analyses, at most 24.6% of the additive genetic variance in hair color was explained by 1000G well-imputed SNPs. Genome-wide association analysis for each hair color showed that SNPs in the MC1R region were significantly associated with red, brown and black hair, and also with light versus dark hair color. Five other known genes (HERC2, TPCN2, SLC24A4, IRF4, and KITLG gave genome-wide significant hits for blond, brown and light versus dark hair color. We did not find and replicate any new loci for hair color.

  16. Sibling relationships and behavior after pediatric traumatic brain injury.

    Science.gov (United States)

    Swift, Erika E; Taylor, H Gerry; Kaugars, Astrida Seja; Drotar, Dennis; Yeates, Keith Owen; Wade, Shari L; Stancin, Terry

    2003-02-01

    To evaluate long-term outcomes for siblings of children with traumatic brain injury (TBI), measures of sibling relationships and sibling behavior were collected an average of 4 years postinjury. The study sample included participants in a larger longitudinal study who had school-aged siblings, including 34 with severe TBI, 30 with moderate TBI, and 39 with orthopedic injuries not involving brain insult (ORTHO group). Group comparisons revealed more negative sibling relationships in families of children with TBI than in families of children in the ORTHO group, but only for mixed-gender sibling pairings. Behavior problems in children with TBI predicted both sibling relationships and sibling behavior problems. The findings indicate a need to monitor the adjustment of siblings and sibling relationships after TBI and to include siblings in family interventions.

  17. A rare case report of cord entanglement in a post-dated monochorionic monoamniotic twins

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    Kasturi Donimath

    2016-01-01

    Full Text Available Monochorionic Monoamniotic (MCMA twin gestations have been associated perinatal mortality rates as high as 28 to 47%. Umbilical cord entanglements and knots, twin-to-twin transfusion syndrome, congenital anomalies, prematurity and intertwin locking during labour is responsible for their high perinatal morbidity and mortality. We report here a case of Cord entanglement in a post-dated MCMA twin pregnancy without any complications. [Int J Reprod Contracept Obstet Gynecol 2016; 5(1.000: 230-231

  18. Craniofacial skeletal dysplasia of opposite-sex dizygotic twins.

    Science.gov (United States)

    Chou, Szu-Ting; Tseng, Yu-Chuan; Pan, Chin-Yun; Chang, Jenny Zwei-Chieng; Chang, Hong-Po

    2011-05-01

    Craniofacial skeletal dysplasia can lead to different skeletal malocclusions. Both environmental factors and heredity contribute to the formation of malocclusions. There are strong familial tendencies in the development of Angle's Class II and III malocclusions. Cases such as opposite-typed (Class II and III) malocclusions with skeletal and dentoalveolar discordance in siblings or dizygotic (DZ) twins have seldom been reported. We describe the rare case of a pair of opposite-sex DZ twins with completely different skeletal malocclusions, and discuss the clinical considerations for treatment. The patients were twins aged 13 years and 4 months. The girl had mandibular prognathism and a Class III dentoskeletal relationship, whereas the boy had skeletal Class II with mandibular retrusion. Several morphological traits have been implicated with hormonal effect. However, there was no evidence of whether the masculinization effect had any impact on jaw size in the female fetus or whether this effect lasted into adolescence. We suggest that, although DZ twins share the same growth environment, genetic or other unknown extrinsic factors can result in discordance of characteristics of the craniofacial skeleton, dentition, and occlusion. Copyright © 2011 Formosan Medical Association & Elsevier. Published by Elsevier B.V. All rights reserved.

  19. Morquio’s Syndrome: A Case Report of Two Siblings

    Directory of Open Access Journals (Sweden)

    Sathish Muthukumar Ramalingam

    2017-01-01

    Full Text Available Morquio syndrome or MPS IVA is a rare type of lysosomal storage disease associated with highly specific dental abnormalities. We present two siblings with enamel hypoplasia and skeletal abnormalities. A diagnosis of mucopolysaccharidosis type IVA was reached based on the clinical, radiographic, and dental findings of the patients. The dental findings are useful diagnostic aid for the early diagnosis of this debilitating disorder.

  20. A family with five siblings affected with nephronophthisis

    Directory of Open Access Journals (Sweden)

    Jumana Albaramki

    2014-01-01

    Full Text Available Nephronophthisis is an autosomal recessive disease that leads to end-stage renal disease. These days, molecular genetic analysis is used pre-emptively for making a definitive diagnosis in patients who have clinical and radiological data suggestive of the disease. Herein, we are reporting a 12-year-old girl who was genetically diagnosed to have juvenile nephronophthisis, which explained the mystery of the chronic kidney disease in her four affected siblings.

  1. Diabetes and perinatal mortality in twin pregnancies.

    Directory of Open Access Journals (Sweden)

    Zhong-Cheng Luo

    Full Text Available BACKGROUND: Diabetes in pregnancy has been associated with a paradoxically reduced risk of neonatal death in twin pregnancies. Risk "shift" may be a concern in that the reduction in neonatal deaths may be due to an increase in fetal deaths (stillbirths. This study aimed to clarify the impact of diabetes on the risk of perinatal death (neonatal death plus stillbirth in twin pregnancies. METHODS: This was a retrospective cohort study of twin births using the largest available dataset on twin births (the U.S. matched multiple birth data 1995-2000; 19,676 neonates from diabetic pregnancies, 541,481 from non-diabetic pregnancies. Cox proportional hazard models were applied to estimate the adjusted hazard ratios (aHR of perinatal death accounting for twin cluster-level dependence. RESULTS: Comparing diabetic versus non-diabetic twin pregnancies, overall perinatal mortality rate was counterintuitively lower [2.1% versus 3.3%, aHR 0.70 (95% confidence intervals 0.63-0.78]. Individually, both stillbirth and neonatal mortality rates were lower in diabetic pregnancies, but we identified significant differences by gestational age and birth weight. Diabetes was associated with a survival benefit in pregnancies completed before 32 weeks [aHR 0.55 (0.48-0.63] or with birth weight =2500 g [aHR 2.20 (1.55-3.13]. CONCLUSIONS: Diabetes in pregnancy appears to be "protective" against perinatal death in twin pregnancies ending in very preterm or very low birth weight births. Prospective studies are required to clarify whether these patterns of risk are real, or they are artifacts of unmeasured confounders. Additional data correlating these outcomes with the types of diabetes in pregnancy are also needed to distinguish the effects of pre-gestational vs. gestational diabetes.

  2. Sibling relationship quality moderates the associations between parental interventions and siblings' independent conflict strategies and outcomes.

    Science.gov (United States)

    Recchia, Holly E; Howe, Nina

    2009-08-01

    This study extends research on sibling conflict strategies and outcomes by examining unique and interactive associations with age, relative birth order, sibling relationship quality, and caregivers' interventions into conflict. Each of 62 sibling dyads (older sibling mean age = 8.39 years; younger sibling mean age = 6.06 years) discussed 1 recurring conflict alone (dyadic negotiation) and a 2nd conflict with their primary parental caregiver (triadic negotiation). Negotiations were coded for children's conflict strategies, outcomes, and caregiver interventions; each family member provided ratings of sibling relationship quality. Results revealed that age was associated with siblings' constructive strategies, particularly in the dyadic negotiation. With age controlled, younger siblings referred more frequently to their own perspective. Caregivers' future orientation in the triadic negotiation was associated with children's future orientation in the dyadic negotiation; however, this association was most evident when sibling relationship quality was high. Similarly, caregivers' past orientation was positively associated with dyadic compromise, especially when relationship quality was high. Results reveal the value of simultaneously considering associations among parental, affective, and developmental correlates of sibling conflict strategies. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

  3. Correlated mortality risks of siblings in Kenya: The role of state dependence

    Directory of Open Access Journals (Sweden)

    Fernando Rajulton

    2008-04-01

    Full Text Available Random-effect models have been useful in demonstrating how unobserved factors are related to infant or child death clustering. Another potential hypothesis is state dependence whereby the death of an older sibling affects the risk of death of a subsequent sibling. Probit regression models incorporating state dependence and unobserved heterogeneity are applied to the 1998 Demographic and Health Survey (DHS data for Kenya. We find that mortality risks of adjacent siblings are dependent: a child whose preceding sibling died is 1.8 times more likely to die. After adjusting for unobserved heterogeneity, the death of the previous child accounts for 40% of child death clustering. Further, eliminating state dependence would reduce infant mortality among second- and higher-order births by 12.5%.

  4. The Role of Adolescent Nutrition and Physical Activity in the Prediction of Verbal Intelligence during Early Adulthood: A Genetically Informed Analysis of Twin Pairs

    Directory of Open Access Journals (Sweden)

    Dylan B. Jackson

    2015-01-01

    Full Text Available A large body of research has revealed that nutrition and physical activity influence brain functioning at various stages of the life course. Nevertheless, very few studies have explored whether diet and exercise influence verbal intelligence as youth transition from adolescence into young adulthood. Even fewer studies have explored the link between these health behaviors and verbal intelligence while accounting for genetic and environmental factors that are shared between siblings. Employing data from the National Longitudinal Study of Adolescent Health, the current study uses a sample of same-sex twin pairs to test whether youth who engage in poorer fitness and nutritional practices are significantly more likely to exhibit reduced verbal intelligence during young adulthood. The results suggests that, independent of the effects of genetic and shared environmental factors, a number of nutritional and exercise factors during adolescence influence verbal intelligence during adulthood. Limitations are noted and suggestions for future research are outlined.

  5. The Texas Twin Project.

    Science.gov (United States)

    Harden, K Paige; Tucker-Drob, Elliot M; Tackett, Jennifer L

    2013-02-01

    Socioeconomic position, racial/ethnic minority status, and other characteristics of the macro-environment may be important moderators of genetic influence on a wide array of psychosocial outcomes. Designed to maximize representation of low socioeconomic status families and racial/ethnic minorities, the Texas Twin Project is an ongoing study of school-age twins (preschool through 12th grade) enrolled in public schools in the Austin, Texas and Houston, Texas metropolitan areas. School rosters are used to identify twin families from a target population with sizable populations of African American (18%), Hispanic/Latino (48%), and non-Hispanic White (27%) children and adolescents, over half of whom meet US guidelines for classification as economically disadvantaged. Initial efforts have focused on a large-scale, family-based survey study involving both parent and child reports of personality, psychopathology, physical health, academic interests, parent-child relationships, and aspects of the home environment. In addition, the Texas Twin Project is the basis for an in-laboratory study of adolescent decision-making, delinquency, and substance use. Future directions include geographic expansion of the sample to the entire state of Texas (with a population of over 25 million) and genotyping of participating twins.

  6. Hypoalbuminemia in Donors with Twin-Twin Transfusion Syndrome

    NARCIS (Netherlands)

    Verbeek, L.; Middeldorp, J. M.; Hulzebos, C. V.; Oepkes, D.; Walther, F. J.; Lopriore, E.

    2013-01-01

    Objective: To estimate the differences in albumin levels between donors and recipients with twin-twin transfusion syndrome (TTTS). Methods: We performed a matched case-control study including twin pairs with TTTS treated conservatively (conservative group) or with fetoscopic laser surgery (laser gro

  7. Siblings and Theory of Mind in Deaf Native Signing Children.

    Science.gov (United States)

    Woolfe, Tyron; Want, Stephen C.; Siegal, Michael

    2003-01-01

    A study examined the basis of "theory of mind" (ToM) reasoning in 20 native signers (ages 4-8) of British Sign Language. Children and their siblings were given a measure of the quality of sibling relations. Sibling quality as perceived by siblings predicted children's ToM score over age and referential communication. (Contains…

  8. Effects of Task Difficulty on Sibling Teaching in Middle Childhood

    Science.gov (United States)

    Howe, Nina; Brody, Marie-Helene; Recchia, Holly

    2006-01-01

    Teaching styles were investigated in 28 middle-class sibling dyads (older sibling M age = 8.2 yrs; younger sibling M age = 5.11 yrs) using two sets of block design tasks (five easy; five hard). Older siblings employed a greater number of strategies (i.e. physical demonstrations, scaffolding, corrective feedback) in the hard than in the easy tasks,…

  9. Support Needs of Siblings of People with Developmental Disabilities

    Science.gov (United States)

    Arnold, Catherine K.; Heller, Tamar; Kramer, John

    2012-01-01

    This qualitative study examines the support needs of adult siblings of people with developmental disabilities. A survey completed by 139 siblings of people with developmental disabilities captured the needs of adult siblings through 2 open-ended questions. A grounded theory approach was used, and the sibling responses anchored the analysis,…

  10. Memory Keepers: A Narrative Study on Siblings Never Known

    Science.gov (United States)

    Kempson, Diane; Murdock, Vicki

    2010-01-01

    Drawing on literature relevant to the impact of sibling death, the authors examined the invisible loss of siblings never known. This article presents findings of a phenomenological study of 15 adult siblings who "storied" the psychological presence and power of a deceased infant sibling never known but who acted as memory keepers for…

  11. Parental Divorce and Sibling Relationships: A Research Note

    Science.gov (United States)

    Poortman, Anne-Rigt; Voorpostel, Marieke

    2009-01-01

    This study examines long-term effects of parental divorce on sibling relationships in adulthood and the role of predivorce parental conflict. It used large-scale retrospective data from the Netherlands that contain reports from both siblings of the sibling dyad. Results show limited effects of parental divorce on sibling contact and relationship…

  12. Partial siamese twin as potential organ donor

    Directory of Open Access Journals (Sweden)

    Rakesh Kapoor

    2010-01-01

    Full Text Available During evaluation of a partial Siamese twin for removal of nonviable parasitic part in an 8-year-old male child, a fully functional kidney was found. The functional status of the extra kidney was found to be within acceptable limits for the purpose of transplant, which was subsequently done in a 24-year-old patient with end-stage renal disease. The recipient is healthy 19 months after the surgery. The possibility of using organs from a partial Siamese twin makes this a unique case report.

  13. Twinned caesium cerium(IV pentafluoride

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    Andrzej Grzechnik

    2014-03-01

    Full Text Available Single-crystals of CsCeF5 were synthesized hydrothermally. The crystal under investigation was twinned by pseudo-merohedry with a twofold rotation around the c axis as an additional twinning operation. The crystal structure is built of layers of distorted edge- and corner-sharing CeF8 square-antiprisms. The Cs+ cations are located between the layers and exhibit coordination numbers of nine. Upon compression, CsCeF5 undergoes an irreversible phase transition at about 1 GPa.

  14. Dialysis for twins

    DEFF Research Database (Denmark)

    Gramkow, Ann-Maria; Aarup, Michael; Andersen, L. L. T.

    2014-01-01

    A 32-year-old woman with known stage-4 chronic kidney disease due to lupus nephritis presented with twin pregnancy after in vitro fertilization at a gestational age of 24 weeks + 3 days because of imminent preterm labour. Repeated ultrasound evaluations confirmed intrauterine growth restriction...... in both twins and polyhydramnios as the cause of imminent preterm labour. After initiation of haemodialysis treatment, ultrasound evaluation showed a significant decrease in amniotic fluids, and also reduction in blood urea nitrogen and in clinical complaints could be observed. At a gestational age of 28...... weeks + 4 days, delivery was performed by Caesarean section. This case study shows that effective treatment of elevated uraemic toxins significantly reduced the morbidity risks of the twins....

  15. The Danish Twin Registry

    DEFF Research Database (Denmark)

    Skytthe, Axel; Christiansen, Lene; Kyvik, Kirsten Ohm;

    2013-01-01

    decade of combining questionnaire and survey data with national demographic, social, and health registers in Statistics Denmark. Second, we describe our most recent data collection effort, which was conducted during the period 2008-2011 and included both in-person assessments of 14,000+ twins born 1931......Over the last 60 years, the resources and the research in the Danish Twin Registry (DTR) have periodically been summarized. Here, we give a short overview of the DTR and a more comprehensive description of new developments in the twenty-first century. First, we outline our experience over the last......-1969 and sampling of biological material, hereby expanding and consolidating the DTR biobank. Third, two examples of intensively studied twin cohorts are given. The new developments in the DTR in the last decade have facilitated the ongoing research and laid the groundwork for new research directions....

  16. Maternal nutrition in twin pregnancy.

    Science.gov (United States)

    Campbell, D M; MacGillivray, I; Tuttle, S

    1982-01-01

    Energy and protein intake as measured by 24-hour urinary nitrogen values are similar in twin and singleton pregnancies. The relationship between urinary nitrogen and nitrogen intake is equally significant in twin and singleton pregnancies. Dietary zinc, copper, and iron are not different in women with twins, nor are the levels of these elements in plasma. These observations are surprising in view of the extra fetal demands on the mother and the different adaptation of twin pregnancies.

  17. Osteogenesis Imperfecta (Type IV with Dental Findings in Siblings

    Directory of Open Access Journals (Sweden)

    Shishir Ram Shetty

    2011-01-01

    Full Text Available Osteogenesis imperfecta (OI is a hereditary disorder characterized by increased tendency for bone fractures due to high fragility. The clinical and radiological features of OI manifest in different age groups, although the disease is congenital in nature. Besides bone fragility, features like laxity of the ligaments, blue sclera, growth retardation, and scoliosis are also observed. In severe cases, respiratory distress and death have been reported. The most important oral finding in OI is the presence of yellowish-brown-coloured brittle teeth characteristic of dentinogenesis imperfecta. Genetic factors play a very important role in the pathogenesis of OI either as a dominant or recessive factor. When a child has OI, there is a 25% chance of the sibling to have the same disorder. We report two cases of OI in siblings born to parents with a history of consanguineous marriage. The clinical and radiological features of the two cases are described in detail.

  18. Parapagus conjoined twins: Complicated anatomy precludes separation

    Directory of Open Access Journals (Sweden)

    Singhal Arbinder

    2006-01-01

    Full Text Available A parapagus set of male conjoined twins was brought to our institution at 12 h after birth. An extensive sharing of the abdominal viscera (single liver, hindgut, abdominal aorta, pelvis (single rectum and anus, genitalia (one set and vertebral column was found. The surgical separation was not considered due to medical and ethical issues.

  19. Relativistic twins or sextuplets?

    CERN Document Server

    Sheldon, E S

    2003-01-01

    A recent study of the relativistic twin 'paradox' by Soni in this journal affirmed that 'A simple solution of the twin paradox also shows anomalous behaviour of rigidly connected distant clocks' but entailed a pedagogic hurdle which the present treatment aims to surmount. Two scenarios are presented: the first 'flight-plan' is akin to that depicted by Soni, with constant-velocity segments, while the second portrays an alternative mission undertaken with sustained acceleration and deceleration, illustrated quantitatively for a two-way spacecraft flight from Earth to Polaris (465.9 light years distant) and back.

  20. Imaging of conjoined twins

    Energy Technology Data Exchange (ETDEWEB)

    McHugh, Kieran [Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom); Kiely, Edward M.; Spitz, Lewis [Great Ormond Street Hospital for Children, Department of Surgery, London (United Kingdom)

    2006-09-15

    The incidence of conjoined twins is estimated to be around 1 in 250,000 live births. There is a distinct female predominance. In this paper the imaging of conjoined twins both antenatally and postnatally is reviewed, in particular taking into consideration recent advances with multidetector CT. Accurate counselling of parents regarding the likely outcome of the pregnancy and the likelihood of successful separation is dependent on good prenatal imaging with ultrasound and MRI. Planning of postnatal surgical separation is aided by accurate preoperative imaging which, depending on the conjoined area, will encompass many imaging modalities, but often relies heavily on CT scanning. (orig.)

  1. The Twin Interdisciplinary Neuroticism Study

    NARCIS (Netherlands)

    Riese, Harriette; Rijsdijk, Fruehling V.; Snieder, Harold; Ormel, Johan

    The Twin Interdisciplinary Neuroticism Study (TWINS) is a three-wave study including >800 twin pairs from the northern part of the Netherlands. The aim of the study is to unravel why neuroticism reflects vulnerability to mental disorders. In this study, we focus on possible mechanisms underlying

  2. A two-session psychological intervention for siblings of pediatric cancer patients: a randomized controlled pilot trial

    Directory of Open Access Journals (Sweden)

    Prchal Alice

    2012-01-01

    Full Text Available Abstract Background Since siblings of pediatric cancer patients are at risk for emotional, behavioral, and social problems, there is considerable interest in development of early psychological interventions. This paper aimed at evaluating the effectiveness of a two-session psychological intervention for siblings of newly diagnosed pediatric cancer patients. Methods Thirty siblings age 6-17 years were randomly assigned to an intervention group or an active control group with standard psychosocial care. The manualized intervention provided to siblings in the first 2 months after the cancer diagnosis of the ill child included medical information, promotion of coping skills, and a psychoeducational booklet for parents. At 4 to 6 weeks, 4 months, and 7 months after the diagnosis, all siblings and their parents completed measures (from standardized instruments of social support, quality of life, medical knowledge, posttraumatic stress symptoms, and anxiety. Results At follow-up siblings in the intervention group showed better psychological well-being, had better medical knowledge, and reported receiving social support from more people. However, the intervention had no effects on posttraumatic stress symptoms and anxiety. Conclusions The results of this pilot trial suggest that a two-session sibling intervention can improve siblings' adjustment, particularly psychological well-being, in the early stage after a cancer diagnosis. Trial Registration ClinicalTrials.gov NCT00296907

  3. A Study on Normal Siblings of Mentally Retarded Persons

    OpenAIRE

    1997-01-01

    This study examined how normal people perceive their mentally retarded siblings and what they see to be their future relationship. Normal siblings of mentally retarded persons were given a questionnaire regarding their relationships with their parents and mentally retarded siblings during childhood and how they introduced their mentally retarded siblings to their fiancees. In most cases, they had good relationships with their mentally retarded siblings during childhood. Most of them also inte...

  4. Twinning in muskox and the cytogenetic investigation of a freemartin

    Directory of Open Access Journals (Sweden)

    N. J. Reindl

    1993-12-01

    Full Text Available The occurrence of twinning has been documented for muskox in both wild and captive populations. Of two known captive twin births only one set survived beyond 120 days. In both cases the twins were male-female pairs and both females showed abnormal sexual development. Two sets of stillborn twins have also been recorded. All four stillborn fetuses were female and none showed anomalies of the reproductive tract upon post-mortem examination. Blood cultures from the surviving male and female twins revealed that both were chimeric, indicating the admixture of fetal blood. Fibroblast cultures were normal for the respective sex of each individual. The freemartin heifer had anatomical abnormalities of the clitoris as well as the secondary sex characteristics of a male.

  5. Twinning Phenomena along and beyond the Bain Path

    Directory of Open Access Journals (Sweden)

    Sebastian Fähler

    2013-10-01

    Full Text Available Twinning is a phenomenon that occurs, e.g., during deformation, martensitic transformation and film growth. The present study shows that the crystallography of twinning can be described by two twinning modes along the complete Bain transformation path and beyond connecting body-centered and face-centered cubic structures. To probe this concept, we used strained epitaxial films of the Fe-Pd magnetic shape memory system. As the substrate acts as an absolute reference frame, we could show by pole figure measurements that all observed twinning can be a body-centered and face-centered cubic twinning mode. This continuously transforms towards identity when approaching the complementary structure.

  6. Finding the lost siblings of the Sun

    Science.gov (United States)

    Liu, Cheng; Feltzing, Sofia; Ruchti, Gregory

    2014-01-01

    We have performed a spectral analysis on 18 stars solar sibling candidate. We found that only one one of the candidateshas solar metallicity and at the same time might have an age comparable to that of the Sun.

  7. Twins and virtual twins: Do genetic (as well as experiential) factors affect developmental risks?

    Science.gov (United States)

    Segal, Nancy L; Tan, Tony Xing; Graham, Jamie L

    2015-08-01

    Factors underlying developmental delays and psychosocial risks are of interest to international adoption communities. The current study administered a Pre-Adoption Adversity (PAA) Questionnaire to mostly American parents raising (a) adopted Chinese twins or (b) same-age unrelated adopted siblings. A goal was to replicate earlier analyses of pre-adoption adversity/adjustment among adopted preschool-age Chinese girls. A second goal was to conduct genetic analyses of four content areas (Developmental Delays at Adoption, Initial Adaptation to Adoption, Crying/Clinging, and Refusal/Avoidance) derived from the PAA Questionnaire. A key finding was that age at adoption added less than other predictors to adoptees' externalizing and internalizing behaviors. Family factors (e.g., parental education) contributed significantly to behavioral outcomes among the adopted Chinese twins. Genetic effects were indicated for all four content areas, with shared environmental effects evident for Developmental Delays at Adoption and Crying/Clinging. Future investigators should consider incorporating genetically sensitive designs into developmental research programs.

  8. Gamma-rays from dark showers with twin Higgs models

    Science.gov (United States)

    Freytsis, Marat; Knapen, Simon; Robinson, Dean J.; Tsai, Yuhsin

    2016-05-01

    We consider a twin WIMP scenario whose twin sector contains a full dark copy of the SM hadrons, where the lightest twin particles are twin pions. By analogy to the standard WIMP paradigm, the dark matter (DM) freezes out through twin electroweak interactions, and annihilates into a dark shower of light twin hadrons. These are either stable or decay predominantly to standard model (SM) photons. We show that this `hadrosymmetric' scenario can be consistent with all applicable astrophysical, cosmological and collider constraints. In order to decay the twin hadrons before the big-bang nucleosynthesis epoch, an additional portal between the SM and twin sector is required. In most cases we find this additional mediator is within reach of either the LHC or future intensity frontier experiments. Furthermore, we conduct simulations of the dark shower and consequent photon spectra. We find that fits of these spectra to the claimed galactic center gamma-ray excess seen by Fermi -LAT non-trivially coincide with regions of parameter space that both successfully generate the observed DM abundance and exhibit minimal fine-tuning.

  9. Gamma-rays from dark showers with twin Higgs models

    Energy Technology Data Exchange (ETDEWEB)

    Freytsis, Marat [Institute of Theoretical Science, University of Oregon,Eugene, OR 97403 (United States); Knapen, Simon; Robinson, Dean J. [Department of Physics, University of California,Berkeley, CA 94720 (United States); Ernest Orlando Lawrence Berkeley National Laboratory,University of California, Berkeley, CA 94720 (United States); Tsai, Yuhsin [Maryland Center for Fundamental Physics, Department of Physics,University of Maryland, College Park, MD 20742 (United States)

    2016-05-03

    We consider a twin WIMP scenario whose twin sector contains a full dark copy of the SM hadrons, where the lightest twin particles are twin pions. By analogy to the standard WIMP paradigm, the dark matter (DM) freezes out through twin electroweak interactions, and annihilates into a dark shower of light twin hadrons. These are either stable or decay predominantly to standard model (SM) photons. We show that this ‘hadrosymmetric’ scenario can be consistent with all applicable astrophysical, cosmological and collider constraints. In order to decay the twin hadrons before the big-bang nucleosynthesis epoch, an additional portal between the SM and twin sector is required. In most cases we find this additional mediator is within reach of either the LHC or future intensity frontier experiments. Furthermore, we conduct simulations of the dark shower and consequent photon spectra. We find that fits of these spectra to the claimed galactic center gamma-ray excess seen by Fermi-LAT non-trivially coincide with regions of parameter space that both successfully generate the observed DM abundance and exhibit minimal fine-tuning.

  10. Fatal stroke after the death of a sibling: a nationwide follow-up study from Sweden.

    Directory of Open Access Journals (Sweden)

    Mikael Rostila

    Full Text Available BACKGROUND: Although less studied than other types of familial losses, the loss of a sibling could be a potential trigger of stroke as it represents a stressful life event. We studied the association between loss of a sibling and fatal stroke up to 18 years since bereavement. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a follow-up study between 1981 and 2002, based on register data covering the total population of Swedes aged 40-69 years (n = 1,617,010. An increased risk of fatal stroke (1.31 CI: 1.05, 1.62 was found among women who had experienced the loss of a sibling. No increase in the overall mortality risk was found in men (1.11 CI: 0.92, 1.33. An elevated risk in the short term (during the second and third half-year after the death was found among both men and women, whereas longer-term elevation in risk was found primarily for women. Both external (1.47 CI: 1.00, 2.17 and not external (1.26 CI: 1.00, 1.60 causes of sibling death showed associations among women. In men, an association was found only if the sibling also died from stroke (1.78 CI: 1.00, 3.17. However, among women, we found an increased risk of stroke mortality if the sibling died from causes other than stroke (1.30 CI: 1.04, 1.62. CONCLUSIONS/SIGNIFICANCE: The findings suggest an increased risk of dying from stroke mortality after the death of a sibling, and that bereavement affects particularly women. It is important for health care workers to follow bereaved siblings and recognize potential changes of stress-levels and health related behaviours that could lead to risk of stroke.

  11. Language abilities in preschool-aged siblings of children with autism spectrum disorders – preliminary report

    Directory of Open Access Journals (Sweden)

    Ewa Pisula

    2015-01-01

    Full Text Available Background The characteristics of autism spectrum disorders (ASD observed among relatives of people affected with autism are referred to as broader autism phenotype (BAP. Among the components of BAP are language and communication skills. Research to date on these skills amongst the relatives of individuals with ASD is inconclusive. Furthermore, limited data are available about preschool-aged siblings of children with ASD. Participants and procedure Eighty-six children aged 4 years and 6 months – 6 years and 11 months took part in the study (32 girls and 54 boys. They were divided into four groups: siblings of children with autism (S/ASD, high-functioning children diagnosed with autism spectrum disorders (HF/ASD, siblings of children with Down syndrome (S/DS and siblings of typically developing children (Controls, C. Communication and language skills were tested using the Vocabulary Test for Children (TSD. It was used to assess two kinds of verbal skills: receptive language (passive and expressive language (active. Results No differences were observed in expressive lanquage or receptive language between siblings of children with ASD and siblings of children with DS as well as typically developing children. In terms of receptive language and general communication skills, siblings of children with ASD scored higher than high functioning children with ASD. High functioning children with ASD displayed difficulties with receptive language, expressive language, general language and communication skills. Conclusions The results suggest that siblings of children with ASD do not display deficits in communication and language skills. It is however important to note that due to a small sample size this study should be considered as preliminary.

  12. Comparing Adolescent Only Children with Those Who Have Siblings on Academic Related Outcomes and Psychosocial Adjustment

    Directory of Open Access Journals (Sweden)

    Zeng-yin Chen

    2014-01-01

    Full Text Available This study uses a large and representative sample of adolescents to test the theoretically informed hypotheses comparing adolescent singletons with those who have siblings. The results found that, for academic related outcomes (educational expectations, time spent on homework, and self-reported grades, there are no differences between singletons and firstborns who have any number of younger siblings. Singletons are also not different from laterborns from two-child families. In contrast, singletons are more advantageous compared to laterborns who have two or more siblings on educational expectations and grades. Singletons also spend more time on homework than laterborns who have three or more siblings. For psychosocial outcomes (psychological distress, susceptibility to negative peer pressure, and problem behaviors, singletons are not different from both firstborns and laterborns with any number of siblings. The findings suggest that singletons are not at any disadvantage compared to their peers who have siblings and they enjoy some advantages over laterborns from medium to large families on academic related outcomes.

  13. Sibling composition and child immunization in India and Pakistan, 1990-2007

    Institute of Scientific and Technical Information of China (English)

    Prashant Kumar Singh; Sulabha Parsuraman

    2014-01-01

    Background: This study aimed to assess trends in gender differentials in child immunization beyond the conventional male-female dichotomy, by considering gender, surviving siblings, birth order and different compositions of older siblings in tandem, during 1990- 2007 in India and Pakistan. Methods: Using different rounds of Demographic and Health Survey datasets, we adopted the World Health Organization guidelines for appraising full immunization among children. Sex composition of surviving older siblings was combined. Cochrane-Armitage and the Chisquare tests were used to test linear and nonlinear trends, respectively. Results: Although child immunization has increased during the period of 1990-2007 in both India and Pakistan, results showed that more than 50% of the eligible children did not receive the recommended immunization. The results also showed that boys and girls with no older surviving siblings and those with only surviving siblings of the opposite sex appeared to have fully immunized proportionally compared with the children with other sibling compositions. Conclusion: The findings confirmed that girls and boys were not always treated equally, and that there was a clear pattern of selective neglect in child immunization in both countries during the period of 1990-2007.

  14. The Positive and Negative Experiences of Caregiving for Siblings of Young People with First Episode Psychosis

    Directory of Open Access Journals (Sweden)

    Siann Bowman

    2017-05-01

    Full Text Available Background: The impact of first episode psychosis (FEP upon parents’ experience of caregiving has been well-documented. However, the determinants and nature of this remain poorly understood in siblings. It is hypothesized that siblings of young people with FEP are also impacted by caregiving and burden. This study aimed to characterize the experience of caregiving for siblings of young people with FEP.Method: Survey methodology was used to explore the experience of 157 siblings in the first 18 months of their brother or sister’s treatment for FEP. Participants reported on their appraisal of the negative and positive aspects of caregiving as measured by the Experience of Caregiving Inventory (ECI. Descriptive statistics were used to establish the results for the total sample as well as for gender and birth order differences. A series of multivariate regression analyses were conducted to determine the relationships between illness characteristics and siblings’ experience of caregiving.Results: Older brothers reported the lowest scores for negative experiences in caregiving and younger sisters reported the highest. Negative experiences in caregiving resulted in less warmth within the sibling relationship and impacted negatively upon quality of life. When the young person with FEP had attempted suicide and/or been physically violent, siblings experienced more caregiver burden. Multivariate analysis showed that female gender was a significant factor in explaining the impact of illness related variables on the experience of caregiving.Conclusion: Suicide attempts and a history of violence resulted in higher caregiving burden for siblings regardless of whether they lived with the young person experiencing FEP or not. Female siblings are at higher risk of negative experiences from caregiving resulting in a reduced quality of life and a changed sibling relationship. Suicide attempts and violence are indicators for intensive case management to

  15. Identical Twins Raised Apart

    Science.gov (United States)

    Farnsworth, David L.

    2015-01-01

    This article describes a bivariate data set that is interesting to students. Indeed, this particular data set, which involves twins and IQ, has sparked more student interest than any other set that I have presented. Specific uses of the data set are presented.

  16. Twin Hub Network (poster)

    NARCIS (Netherlands)

    Kreutzberger, E.D.; Konings, J.W.

    2014-01-01

    Twin hub network, a European Interreg IVB project, aims at making intermodal rail transport within, to and from North West Europe more competitive, in particular between seaports and inland terminals. Improving rail competitiveness enables to shift freight flows from road to rail, providing a more s

  17. Multiple risk factors related to familial predisposition to anterior cruciate ligament injury: fraternal twin sisters with anterior cruciate ligament ruptures.

    Science.gov (United States)

    Hewett, T E; Lynch, T R; Myer, G D; Ford, K R; Gwin, R C; Heidt, R S

    2010-09-01

    A multifactorial combination of predictors may increase anterior cruciate ligament (ACL) injury risk in athletes. The objective of this twin study was to examine these risk factors to identify commonalities in risk factors that predisposed female fraternal twins to ACL injury. Female twins in high-risk sports were prospectively measured prior to an injury for neuromuscular control using three-dimensional motion analysis during landing, hamstrings and quadriceps muscular strength on a dynamometer and joint laxity using a modified Beighton-Horan index and a Compu-KT arthrometer. Intraoperative measures of femoral intercondylar notch width were recorded during ACL reconstruction. Abduction angles were increased at one knee in both of the twin sister athletes relative to uninjured controls at initial contact and at maximum displacement during landing. The twin female athletes that went on to ACL injury also demonstrated decreased peak knee flexion motion at both knees than uninjured females during landing. The twin athletes also had increased joint laxity and decreased hamstrings to quadriceps (H/Q) torque ratios compared to controls. Femoral intercondylar notch widths were also below the control mean in the twin siblings. Prescreened mature female twins that subsequently experienced ACL injury demonstrated multiple potential risk factors including: increased knee abduction angles, decreased knee flexion angles, increased general joint laxity, decreased H/Q ratios and femoral intercondylar notch width.

  18. Mitral valve regurgitation in twins

    DEFF Research Database (Denmark)

    Bakkestrøm, Rine; Larsen, Lisbeth Aagaard; Møller, Jacob Eifer

    2016-01-01

    BACKGROUND: Smaller observational studies have suggested familial clustering of mitral regurgitation (MR). Using a large twin cohort, the aims were to assess MR concordance rates and assess mortality in MR twins and unaffected cotwins. METHODS: Through the Danish Twin Registry, twins...... with an International Classification of Diseases, Eighth Revision and Tenth Revision diagnosis code of MR born 1880-1989 were identified and proband-wise concordance rates were calculated. To assess whether having a cotwin with MR affected survival, 10 matched twins without MR (n = 5,575) were selected for each MR twin...... (n = 562), and all-cause mortality rates were assessed. RESULTS: Among the 87,432 twins alive January 1, 1977, or later, 494 (0.57%) MR individuals were identified. Six MR concordant pairs were found, of which 3 were monozygotic. Proband-wise concordance rate when accounting for right censoring...

  19. A prospective study of twinning and perinatal mortality in urban Guinea-Bissau

    Directory of Open Access Journals (Sweden)

    Bjerregaard-Andersen Morten

    2012-12-01

    Full Text Available Abstract Background Despite twinning being common in Africa, few prospective twin studies have been conducted. We studied twinning rate, perinatal mortality and the clinical characteristics of newborn twins in urban Guinea-Bissau. Methods The study was conducted at the Bandim Health Project (BHP, a health and demographic surveillance site in Bissau, the capital of Guinea-Bissau. The cohort included all newborn twins delivered at the National Hospital Simão Mendes and in the BHP study area during the period September 2009 to August 2011 as well as singleton controls from the BHP study area. Data regarding obstetric history and pregnancy were collected at the hospital. Live children were examined clinically. For a subset of twin pairs zygosity was established by using genetic markers. Results Out of the 5262 births from mothers included in the BHP study area, 94 were twin births, i.e. a community twinning rate of 18/1000. The monozygotic rate was 3.4/1000. Perinatal mortality among twins vs. singletons was 218/1000 vs. 80/1000 (RR = 2.71, 95% CI: 1.93-3.80. Among the 13783 hospital births 388 were twin births (28/1000. The hospital perinatal twin mortality was 237/1000. Birth weight  Conclusions Twins had a very high perinatal mortality, three-fold higher than singletons. A birth weight 

  20. Urticaria in Monozygotic and Dizygotic Twins

    Directory of Open Access Journals (Sweden)

    Simon Francis Thomsen

    2012-01-01

    Full Text Available Aim. To identify risk factors for urticaria, to determine the relative proportion of the susceptibility to urticaria that is due to genetic factors in an adult clinical twin sample, and to further determine whether the genetic susceptibility to urticaria overlaps with the genetic susceptibility to atopic diseases. Methods. A total of 256 complete twin pairs and 63 single twins, who were selected from sibships with self-reported asthma via a questionnaire survey of 21,162 adult twins from the Danish Twin Registry, were clinically interviewed about a history of urticaria and examined for atopic diseases. Data were analysed with Cox proportional hazards regression and variance components models. Results. A total of 151 individuals (26% had a history of urticaria, whereas 24 (4% had had symptoms within the past year. Female sex, HR=2.09 (1.46–2.99, P=0.000; hay fever, HR=1.92 (1.36–2.72, P=0.000; and atopic dermatitis, HR=1.44 (1.02–2.06, P=0.041 were significant risk factors for urticaria. After adjustment for sex and age at onset of urticaria in the index twin, the risk of urticaria was increased in MZ cotwins relative to DZ cotwins, HR=1.42 (0.63–3.18, P=0.394. Genetic factors explained 45% (16–74%, P=0.005, of the variation in susceptibility to urticaria. The genetic correlation between urticaria and hay fever was 0.45 (0.01–0.89, P=0.040. Conclusions. Susceptibility to urticaria is partly determined by genetic factors. Urticaria is more common in women, and in subjects with hay fever and atopic dermatitis, and shares genetic variance with hay fever.

  1. The application of eigensymmetries of face forms to X-ray diffraction intensities of crystals twinned by 'reticular merohedry'.

    Science.gov (United States)

    Klapper, H; Hahn, Th

    2012-01-01

    This paper is an extension of a previous treatment of `twins by merohedry' with full lattice coincidence [Σ = 1, Klapper & Hahn (2010). Acta Cryst. A66, 327-346] to `twins by reticular merohedry' with partial lattice coincidence (Σ > 1). Again, the sets of symmetrically equivalent reflections {hkl} are considered as sets of equivalent faces (face forms) {hkl}, and the behaviour of the oriented eigensymmetries of these forms under the action of a twin operation is used to determine the X-ray reflection sets, the intensities of which are affected or not affected by the twinning. The following cases are treated: rhombohedral obverse/reverse Σ3 twins, cubic Σ3 (spinel) twins, tetragonal Σ5 twins (twin elements m'(120), 2'[ ̅210]) and hexagonal Σ7 twins (m'(12 ̅30), 2'[2 ̅10]). For each case the twin laws for all relevant point groups are defined, and the twin diffraction cases A (intensity of twin-related reflection sets not affected), B1 (intensity affected), B2 (intensity affected only by anomalous scattering) and S (single, i.e. non-coincident reflection sets) are derived for all twin laws. A special treatment is provided for the cubic Σ3 twins, where the cubic face forms first have to be split into up to four rhombohedral subforms with a threefold axis along one of the four cube directions, here [111]. These subforms exhibit different twin diffraction cases analogous to those derived for the rhombohedral obverse/reverse Σ3 twins. A complete list of the split forms and their diffraction cases for all cubic point groups and all Σ3 twin elements is given. The application to crystal structure determination of crystals twinned by reticular merohedry and to X-ray topographic mapping of twin domains is discussed.

  2. Brazilian Twin Registry: A Bright Future for Twin Studies/Twin Research: Twin Study of Alcohol Consumption and Mortality; Oxygen Uptake in Adolescent Twins/In the News: Superfecundated Twins In Vietnam; Adolescent Twin Relations; Twin and Triplet Co-Workers; A Special Twin Ultrasound; Monozygotic Twins With Different Skin Color; Identical Twin Returns from Space.

    Science.gov (United States)

    Segal, Nancy L

    2016-06-01

    The establishment of the Brazilian Twin Registry for the study of genetic, social, and cultural influences on behavior is one of eleven newly funded projects in the Department of Psychology at the University of São Paulo. These 11 interrelated projects form the core of the university's Center for Applied Research on Well-Being and Human Behavior. An overview of the planned twin research and activities to date is presented. Next, two recent twin studies are reviewed, one on the relationship between alcohol consumption and mortality, and the other on factors affecting maximal oxygen uptake. Twins cited in the media include the first identified superfecundated twins in Vietnam, adolescent twin relations, twins and triplets who work together, monozygotic twins with different skin tones and a co-twin control study that addresses the effects of space travel.

  3. Exploring Subclinical Phenotypic Features in Twin Pairs Discordant for Cleft Lip and Palate

    DEFF Research Database (Denmark)

    Leslie, Elizabeth J; Carlson, Jenna C; Cooper, Margaret E

    2017-01-01

    OBJECTIVE: Monozygotic twins of an individual with an orofacial cleft have a significantly elevated risk for orofacial cleft compared with the general population, but still the concordance rate for orofacial cleft in monozygotic twins is about 40% to 50%. The goal of this study was to determine...... whether unaffected cotwins have an increased frequency of orbicularis oris muscle defects, a subclinical form of orofacial cleft. The presence of such defects may reduce the overall rate of discordance. METHOD: A total of 63 discordant monozygotic and dizygotic twin pairs, 262 unaffected nontwin siblings......, and 543 controls with no history of orofacial clefts were assessed for orbicularis oris defects by high-resolution ultrasound. Frequencies were compared by the Fisher exact test. RESULTS: Unaffected cotwins from discordant monozygotic pairs had a higher frequency of defects (12.5%) than the other test...

  4. Sibling Voices: The Self-Reported Mental Health of Siblings of Children with a Disability

    Science.gov (United States)

    Giallo, Rebecca; Gavidia-Payne, Susana; Minett, Belinda; Kapoor, Aparna

    2012-01-01

    Background: There is increasing interest in the experiences and well-being of siblings growing up with a brother or sister with a disability in Australia. However, research to date has primarily obtained parent reports of sibling adjustment and mental health. Therefore, the aim of the current study was threefold: (1) to report on the mental health…

  5. First-born siblings show better second language skills than later born siblings.

    Science.gov (United States)

    Keller, Karin; Troesch, Larissa M; Grob, Alexander

    2015-01-01

    We examined the extent to which three sibling structure variables number of siblings, birth order, and presence of an older sibling at school age are linked to the second language skills of bilingual children. The research questions were tested using an ethnically heterogeneous sample of 1209 bilingual children with German as a second language. Controlling for children's age, sex, nationality, number of children's books at home, family language and parental German language skills, hierarchical regression analyses showed an inverse relationship between the number of siblings and second language skills: the more siblings a child had, the lower was his/her second language proficiency. This relationship was mediated by attendance in early education institutions. Moreover, first-born siblings showed better second language skills than later born siblings. The current study revealed that the resource dilution model, i.e., the decrease in resources for every additional sibling, holds for second language acquisition. Moreover, the results indicate that bilingual children from families with several children benefit from access to early education institutions.

  6. Associations between Social Understanding, Sibling Relationship Quality, and Siblings' Conflict Strategies and Outcomes

    Science.gov (United States)

    Recchia, Holly E.; Howe, Nina

    2009-01-01

    Sibling relationship quality and social understanding (second-order false belief, conflict interpretation, and narrative conflict perspective references) were examined as unique and interactive correlates of sibling conflict behavior in 62 dyads (older M age = 8.39 years and younger M age = 6.06 years). High-quality relationships were associated…

  7. Longitudinal Links between Older Sibling Features and Younger Siblings' Academic Adjustment during Early Adolescence

    Science.gov (United States)

    Bouchey, Heather A.; Shoulberg, Erin K.; Jodl, Kathleen M.; Eccles, Jacquelynne S.

    2010-01-01

    This study investigated prospective relations between older siblings' support and academic engagement and younger siblings' academic adjustment from 7th to post-8th grade. The study was unique in that it incorporated a sample of both African American and European American adolescents. Also investigated was the extent to which the gender…

  8. Associations between Social Understanding, Sibling Relationship Quality, and Siblings' Conflict Strategies and Outcomes

    Science.gov (United States)

    Recchia, Holly E.; Howe, Nina

    2009-01-01

    Sibling relationship quality and social understanding (second-order false belief, conflict interpretation, and narrative conflict perspective references) were examined as unique and interactive correlates of sibling conflict behavior in 62 dyads (older M age = 8.39 years and younger M age = 6.06 years). High-quality relationships were associated…

  9. Hydropic Placenta as a First Manifestation of Twin-Twin Transfusion in a Monochorionic Diamniotic Twin Pregnancy

    NARCIS (Netherlands)

    de Laat, Monique W. M.; Manten, Gwendoline T. R.; Nikkels, Peter G. J.; Stoutenbeek, Philip

    2009-01-01

    Monochorionic twin pregnancies are at a 10% to 1.5% risk of developing twin-twin transfusion syndrome (TTTS).(1) Monitoring such pregnancies is aimed at evaluating the fetal condition by measuring the amount of amniotic fluid, Doppler parameters, and fetal growth. Twin-twin transfusion syndrome may

  10. Hydropic Placenta as a First Manifestation of Twin-Twin Transfusion in a Monochorionic Diamniotic Twin Pregnancy

    NARCIS (Netherlands)

    de Laat, Monique W. M.; Manten, Gwendoline T. R.; Nikkels, Peter G. J.; Stoutenbeek, Philip

    Monochorionic twin pregnancies are at a 10% to 1.5% risk of developing twin-twin transfusion syndrome (TTTS).(1) Monitoring such pregnancies is aimed at evaluating the fetal condition by measuring the amount of amniotic fluid, Doppler parameters, and fetal growth. Twin-twin transfusion syndrome may

  11. Hydropic Placenta as a First Manifestation of Twin-Twin Transfusion in a Monochorionic Diamniotic Twin Pregnancy

    NARCIS (Netherlands)

    de Laat, Monique W. M.; Manten, Gwendoline T. R.; Nikkels, Peter G. J.; Stoutenbeek, Philip

    2009-01-01

    Monochorionic twin pregnancies are at a 10% to 1.5% risk of developing twin-twin transfusion syndrome (TTTS).(1) Monitoring such pregnancies is aimed at evaluating the fetal condition by measuring the amount of amniotic fluid, Doppler parameters, and fetal growth. Twin-twin transfusion syndrome may

  12. Reared-Apart Chinese Twins: Chance Discovery/Twin-Based Research: Twin Study of Media Use; Twin Relations Over the Life Span; Breast-Feeding Opposite-Sex Twins/Print and Online Media: Twins in Fashion; Second Twin Pair Born to Tennis Star; Twin Primes; Twin Pandas.

    Science.gov (United States)

    Segal, Nancy L

    2017-04-01

    A January 2017 reunion of 10-year-old reared-apart Chinese twin girls was captured live on ABC's morning talk show Good Morning America, and rebroadcast on their evening news program Nightline. The twins' similarities and differences, and their participation in ongoing research will be described. This story is followed by reviews of twin research concerning genetic and environmental influences on media use, twin relations across the lifespan and the breast-feeding of opposite-sex twins. Popular interest items include twins in fashion, the second twin pair born to an internationally renowned tennis star, twin primes and twin pandas.

  13. Sibling Gender Composition and Preferences for STEM Education

    DEFF Research Database (Denmark)

    Brenøe, Anne Ardila

    2017-01-01

    -parent interactions. Parents with mixed sex children gender-specialize their parenting more and spend more quality time with their same sex child than parents with same sex children. Moreover, I show that young boys with an opposite sex sibling are exposed to more gender-stereotypical behavior within the family than...... of the younger siblings' gender allows me to estimate the causal effect of having an opposite compared to same sex sibling. Overall, having an opposite sex sibling makes educational choices more gender-stereotypical for both genders. Having an opposite sex sibling reduces women's probability to enroll in any...... boys with a same sex sibling....

  14. Pygopagus Conjoined Twins for Separation Surgery: an Interesting Experience

    Directory of Open Access Journals (Sweden)

    Sanwatsarkar Sadhana

    2013-05-01

    Full Text Available Conjoined twins are rarely encountered in the clinical practice of the anaesthetist and the issues that have to be considered in their anaesthetic management are unique and fascinating. Pygopagus are one of the rare type of conjoined twins with only a handful of cases reported in the literature. We present the case of one and half month old male pygopagus conjoined twins who were joined together dorsally in lower lumbar and sacral region and shared a single thecal sac. They were brought to our hospital for separation surgery.

  15. Reengineering Aircraft Structural Life Prediction Using a Digital Twin

    Directory of Open Access Journals (Sweden)

    Eric J. Tuegel

    2011-01-01

    Full Text Available Reengineering of the aircraft structural life prediction process to fully exploit advances in very high performance digital computing is proposed. The proposed process utilizes an ultrahigh fidelity model of individual aircraft by tail number, a Digital Twin, to integrate computation of structural deflections and temperatures in response to flight conditions, with resulting local damage and material state evolution. A conceptual model of how the Digital Twin can be used for predicting the life of aircraft structure and assuring its structural integrity is presented. The technical challenges to developing and deploying a Digital Twin are discussed in detail.

  16. Minimal Mirror Twin Higgs

    CERN Document Server

    Barbieri, Riccardo; Harigaya, Keisuke

    2016-01-01

    In a Mirror Twin World with a maximally symmetric Higgs sector the little hierarchy of the Standard Model can be significantly mitigated, perhaps displacing the cutoff scale above the LHC reach. We show that consistency with observations requires that the Z2 parity exchanging the Standard Model with its mirror be broken in the Yukawa couplings. A minimal such effective field theory, with this sole Z2 breaking, can generate the Z2 breaking in the Higgs sector necessary for the Twin Higgs mechanism, and has constrained and correlated signals in invisible Higgs decays, direct Dark Matter Detection and Dark Radiation, all within reach of foreseen experiments. For dark matter, both mirror neutrons and a variety of self-interacting mirror atoms are considered. Neutrino mass signals and the effects of a possible additional Z2 breaking from the vacuum expectation values of B-L breaking fields are also discussed.

  17. Emergence of Digital Twins

    OpenAIRE

    Datta, Shoumen Palit Austin

    2016-01-01

    Multiple forms of digital transformation are imminent. Digital Twins represent one concept. It is gaining momentum because it may offer real-time transparency. Rapid diffusion of digital duplicates faces hurdles due to lack of semantic interoperability between architectures, standards and ontologies. The technologies necessary for automated discovery are in short supply. Progression of the field depends on convergence of information technology, operational technology and protocol-agnostic tel...

  18. Nutrition in twin pregnancy.

    Science.gov (United States)

    MacGillivray, I

    1979-01-01

    The urinary nitrogen output appears to be related to both protein and energy intake, so that women having heavier babies probably eat more, although this may simply mean that they are larger women. Women with twin pregnancies have been found to have a lesser urinary nitrogen output, but it seems unlikely that this be due to lower intakes. They might simply utilize their diet more efficiently--a hypothesis that is now being tested.

  19. Family dynamics and young children's sibling victimization.

    Science.gov (United States)

    Tucker, Corinna Jenkins; Finkelhor, David; Turner, Heather; Shattuck, Anne M

    2014-10-01

    This research examines how family dynamics like interparental conflict, family violence, and quality of parenting are associated with young children's experiences of sibling victimization. We use nationally representative data from interviews with caregivers of 1,726 children aged 2 to 9 years of age. We hypothesized different family dynamics predictors for a composite of common types of sibling victimization (property, psychological, and mild physical aggression) in comparison to severe physical sibling victimization (victimization that includes physical aggression with a weapon and/or injury). Multinomial regression results showed that sibling victimization in general was associated with negative family dynamics but that children in the severe group had even less parental warmth, poor parental supervision, and greater exposure to interparental conflict and family violence than children in the common types victimization group. Different aspects of family dynamics contribute to sibling victimization, but possibly in different ways and with different consequences. The findings underscore the importance of a family systems theory approach to clinical and intervention work.

  20. INTEGRATED TWIN TOWERS DAN ISLAMISASI ILMU

    Directory of Open Access Journals (Sweden)

    Syaifuddin Syaifuddin

    2013-05-01

    Full Text Available This paper shows some idea as follows: First, integrated design of the Twin Towers as the changing action from IAIN to UIN Sunan Ampel. The religion and general knowledge’s position of Twin Towers’ integrated design is not mixed into one, but it works individually, and at the certain time are united in mutual dialogue. Second, Islamize design is done in order to criticize the general knowledge which has western sources and are secular, materialistic, and individualistic. In the process to Islamize the knowledge, Islamic knowledge tries to intervene the general knowledge in order to filter it so the knowledge will be Islamized. Consequently, to Islamize knowledge is to give an Islamic concept into general knowledge. Third, there are the similarities and differences between integrated design knowledge based on Islamic knowledge and integrated Twin Towers. The difference is in its epistemology process. The similarity is in the curriculum (ontology and objective (axiology. In the curriculum, the examined knowledge is religion and general knowledge. While the objective, Islamize knowledge and integrated Twin Towers aims to integrate religion and general knowledge, to dialogue, to communicate, and to synergy, so it can be a knowledge which is intact-integral-integrative.

  1. Tribute to dr louis keith: twin and physician extraordinaire/twin research reports: influences on asthma severity; chimerism revisited; DNA strand break repair/media reports: twins born apart; elevated twin frequencies; celebrity father of twins; conjoined twinning.

    Science.gov (United States)

    Segal, Nancy L

    2014-10-01

    The International Society for Twin Studies has lost a valued friend and colleague. Dr Louis Keith, Emeritus Professor of Obstetrics and Gynecology at Northwestern University, in Chicago, passed away on Sunday, July 6, 2014. His life and work with twins will be acknowledged at the November 2014 International Twin Congress in Budapest, Hungary. Next, twin research reports on the severity of asthma symptoms, a case of chimerism, and factors affecting DNA breakage and repair mechanisms are reviewed. Media reports cover twins born apart, elevated twin frequencies, a celebrity father of twins, and a family's decision to keep conjoined twins together.

  2. Socioeconomic position and twins' health

    DEFF Research Database (Denmark)

    Osler, Merete; McGue, Matt; Christensen, Kaare

    2007-01-01

    of middle-aged Danish twins was conducted in 1998-99. The study population included 1266 like-sex twin pairs [52.5% monozygotic (MZ) and 47.6% dizygotic (DZ)]. Data were obtained on childhood and adult social class and on height, BMI, grip strength, depression symptoms, self-rated health, cognitive function......, prenatal and rearing environmental factors from environmental factor later in life, we compared the health status among male and female twin pairs who lived together during childhood and were discordant or concordant on adult socioeconomic position. METHODS: A cross-sectional survey among a random sample......, physical activity, smoking, alcohol and food intake. RESULTS: The expected associations between the individual twins' adult social class and health measures were observed. Among DZ male twins discordant on adult social class, the higher social class twin was on average significantly taller and had higher...

  3. Twin-to-twin delivery time: neonatal outcome of the second twin.

    Science.gov (United States)

    Schneuber, Susanne; Magnet, Eva; Haas, Josef; Giuliani, Albrecht; Freidl, Thomas; Lang, Uwe; Bjelic-Radisic, Vesna

    2011-12-01

    To examine the effect of twin-to-twin delivery time (TTDT) on neonatal outcome. We evaluated twin deliveries >34 weeks of gestation. Twin pregnancies with both twins delivered by cesarean section and pregnancies with antenatal complications were excluded. We analyzed TTDT and neonatal outcomes of the second twin (umbilical arterial pH value (pH(art)), Apgar scores at 1, 5 and 10 minutes, need for intensive care). The study population was divided into two homogenous groups based on the mode of delivery: (A) vertex presentation and vaginal delivery of both twins, (B) vertex presentation and vaginal or vaginal operative delivery of twin I, breech or transverse presentation and vaginal breech delivery or cesarean section (CS) of twin II. A total of 207 twin pairs were included in our study. In Group A (n = 151) there were no significant correlations between TTDT and pH(art) or Apgar scores at 1,5 and 10 minutes of twin II (p = .156; 0.861; 0.151 and 0.384, respectively). In Group B (n = 56), the mean pH(art) of twin II was inversely correlated to TTDT, but not significantly (p = .417). TTDT was inversely related to 1-min and 5-min Apgar scores, but not significantly (p = .330; p = .138, respectively). The 10-min Apgar score showed no correlation with TTDT (p = .638). Increasing TTDT was not associated with adverse fetal outcome. Expectant management of the second twin appears possible and elapsed time alone does not appear to be an indication for intervention.

  4. Terpenoid variations within and among half-sibling avocado trees, Persea americana Mill. (Lauraceae.

    Directory of Open Access Journals (Sweden)

    Jerome Niogret

    Full Text Available Chemical analyses were conducted to determine the qualitative and quantitative differences in monoterpenes and sesquiterpenes in plant material from avocado trees, Persea americana Mill. (Lauraceae. The initial study analyzed plant material sampled from the trunk to the leaves through different branch diameters to quantify proximo-distal spatial differences within a tree. All trees were seedlings initiated from a single maternal tree. Two-way analysis of variance was conducted on 34 chemicals that comprised at least 3% of the total chemical content of at least one tree and/or location within a tree. There were significant interactions between genotype and location sampled for most chemicals. Parentage analysis using microsatellite molecular markers (SSR's determined that the four trees had three fathers and that they represented two full-siblings and two half-sibling trees. Descriptive discriminant analysis found that both genotype and location within a tree could be separated based on chemical content, and that the chemical content from full-siblings tended to be more similar than chemical content from half-siblings. To further explore the relationship between genetic background and chemical content, samples were analyzed from leaf material from 20 trees that included two sets of full-sibling seedling trees, the maternal tree and the surviving paternal tree. Descriptive discriminant analysis found good separation between the two full-sibling groups, and that the separation was associated with chemistry of the parental trees. Six groups of chemicals were identified that explained the variation among the trees. We discuss the results in relation to the discrimination process used by wood-boring insects for site-selection on host trees, for tree selection among potential host trees, and the potential use of terpenoid chemical content in chemotaxonomy of avocado trees.

  5. The neonatal outcome in twin versus triplet and quadruplet pregnancies

    Directory of Open Access Journals (Sweden)

    Fatemeh Nasseri

    2009-02-01

    Full Text Available

    • BACKGROUND: To assess the risk of neonatal mortality and morbidity in twin, triplet and quadruplet pregnancies.
    • METHODS: In a retrospective study, the neonatal outcome of all twin, triplet and quadruplet gestations delivered from October 2001 to September 2006 was reviewed. The neonatal outcome of triples and quadruplets was compared with a matched group of twins for gestational age.
    • RESULTS: During a 5-year period, 511 sets of twin pregnancies, 42 sets of triplet and 5 sets of quadruplet pregnancies were studied. The mean of gestational age for twins, triplets and quadruplets were 33.92 ± 3.5 weeks, 30.92 ± 3.8 weeks and 31.60 ± 2.0 weeks, respectively, (P = 0.0001. Triplets and quadruplets weighed less than twins, (P = 0.0001. Neonatal mortality was 13.5% for twins, 26.8% for triplets and 30% for quadruplets. In vitro fertilization, use of ovulation induction agents, and cesarean delivery in the women with triplet and quadruplet were significantly higher than in those with twin pregnancies, (P = 0.0001. The mean age of mothers with triplets and quadruplets was significantly higher than with twins (P = 0.026. There was not a significant difference in respiratory and non-respiratory short outcomes between triplets, quadruplets and twins when matched for gestational age. Apgar score at 1 and 5 minutes was significantly lower in triplets and quadruplets than twins. There was no influence of birth order on neonatal mortality of triplet pregnancy. Neonatal mortality of triplet births was significantly decreased over the 5 years of the study period.
    • CONCLUSIONS: Triplets and quadruplets have a similar neonatal outcome as twins when matched for gestational age. There is no influence of birth on the neonatal mortality of triplet pregnancy. It appears that outcome is mainly dependent on gestational age.
    • KEYWORDS: Neonatal

    • Trojan twin planets

      Science.gov (United States)

      Dvorak, R.; Loibnegger, B.; Schwarz, R.

      2017-03-01

      The Trojan asteroids are moving in the vicinity of the stable Lagrange points L_4 and L_5 of the gas giants Jupiter, Uranus and Neptune. Their motion can be described and understood with the aid of the restricted three-body problem. As an extension of this problem we investigate how stable motion close to the Lagrange points of two massive bodies can exist. This configuration can be described as the Trojan Twin Problem when we regard the two additional bodies as having a mass significantly smaller than the the two primary bodies: a star in the center (m_1) and an additional Jupiter-like mass (m_2). Using this 4-body problem we have undertaken numerical investigations concerning possible stable "twin orbits". However, these two bodies (m_3 and m_4) in Trojan-like orbits may have quite different masses. We decided to choose 6 different scenaria for this problem: as primary body, m2, we have taken a Jupiter-like planet, a Saturn-like one, and a super-Earth with 10 Earthmasses (m_{Earth}) respectively. As quasi twin planets, we have used different mass ratios namely objects for m3 and m4 from 10m_{Earth} to Moon like ones. We found different stable configurations depending on the involved masses and the initial distances between the twins (always close to the Lagrange point). Although the formation of such a configuration seems to be not very probable we should not exclude that it exists regarding the huge number of planets even in our own galaxy. This model is of special interest when the most massive planet (m_2) is moving on an orbit in the habitable zone around a main sequence star. One can use our results of stable orbits of Trojan Twin Planets (or asteroids) for extrasolar systems having as second primary a Jupiter-like, a Saturn-like or a super-Earth like planet around a star similar to our Sun.

    • Should selecting saviour siblings be banned?

      Science.gov (United States)

      Sheldon, S; Wilkinson, S

      2004-12-01

      By using tissue typing in conjunction with preimplantation genetic diagnosis doctors are able to pick a human embryo for implantation which, if all goes well, will become a "saviour sibling", a brother or sister capable of donating life-saving tissue to an existing child. This paper addresses the question of whether this form of selection should be banned and concludes that it should not. Three main prohibitionist arguments are considered and found wanting: (a) the claim that saviour siblings would be treated as commodities; (b) a slippery slope argument, which suggests that this practice will lead to the creation of so-called "designer babies"; and (c) a child welfare argument, according to which saviour siblings will be physically and/or psychologically harmed.

    • Cognitive performance and psychosocial functioning in patients with bipolar disorder, unaffected siblings, and healthy controls

      Directory of Open Access Journals (Sweden)

      Mirela P. Vasconcelos-Moreno

      2016-01-01

      Full Text Available Objective: To assess cognitive performance and psychosocial functioning in patients with bipolar disorder (BD, in unaffected siblings, and in healthy controls. Methods: Subjects were patients with BD (n=36, unaffected siblings (n=35, and healthy controls (n=44. Psychosocial functioning was accessed using the Functioning Assessment Short Test (FAST. A sub-group of patients with BD (n=21, unaffected siblings (n=14, and healthy controls (n=22 also underwent a battery of neuropsychological tests: California Verbal Learning Test (CVLT, Stroop Color and Word Test, and Wisconsin Card Sorting Test (WCST. Clinical and sociodemographic characteristics were analyzed using one-way analysis of variance or the chi-square test; multivariate analysis of covariance was used to examine differences in neuropsychological variables. Results: Patients with BD showed higher FAST total scores (23.90±11.35 than healthy controls (5.86±5.47; p < 0.001 and siblings (12.60±11.83; p 0.001. Siblings and healthy controls also showed statistically significant differences in FAST total scores (p = 0.008. Patients performed worse than healthy controls on all CVLT sub-tests (p < 0.030 and in the number of correctly completed categories on WCST (p = 0.030. Siblings did not differ from healthy controls in cognitive tests. Conclusion: Unaffected siblings of patients with BD may show poorer functional performance compared to healthy controls. FAST scores may contribute to the development of markers of vulnerability and endophenotypic traits in at-risk populations.

    • Prevalence of celiac disease in siblings of Iranian patients with celiac disease

      Directory of Open Access Journals (Sweden)

      Bashir Chomeili

      2011-06-01

      Full Text Available CONTEXT: Celiac disease, one of the best-known autoimmune human leukocyte antigen-dependent disorders, has a relatively increased prevalence in first-degree relatives. OBJECTIVE: To determine the prevalence of celiac disease in siblings of patients with confirmed celiac disease. METHODS: Siblings of confirmed celiac disease patients in our center were identified and enrolled in this study. Their serum immunoglobulin A and tissue transglutaminase antibody-enzyme-linked immunosorbent assay (anti-tissue transglutaminase, immunoglobulin A, and immunoglobulin G were measured and multiple endoscopic duodenal biopsy specimens were obtained with parental consensus. Celiac disease was confirmed by observation of characteristic histological changes. RESULTS: A total of 49 children (male, 29; female, 20; age, 2-16 years with confirmed celiac disease in a pediatric gastroenterology ward were studied from 1999 to 2006. We found 30 siblings (female, 16 all shared in both parents. The only measurement available was for immunoglobulin A tissue transglutaminase antibody. A duodenal biopsy was performed in all 30 siblings. Clinical findings such as abdominal pain, fatigue, growth retardation and diarrhea were found in 53.3% of the completely studied siblings, and positive serology without histological changes was identified in four cases. Both serology and biopsy (confirmed new cases were positive in 2 of the 30 siblings. CONCLUSION: High prevalence of celiac disease among siblings of patients with confirmed celiac disease necessitates serologic screening (and confirmatory biopsy if indicated in families having celiac disease. It is advantageous to diagnose the disease as soon as possible because early diagnosis and diet intervention may prevent serious complications such as growth retardation, short stature, chronic diarrhea, and malignancy.

    • Rastreamento de sinais e sintomas de transtornos do espectro do autismo em irmãos Screening for signs and symptoms of autism spectrum disorders in siblings

      Directory of Open Access Journals (Sweden)

      Tatiana Pontrelli Mecca

      2011-01-01

      Full Text Available Os transtornos globais do desenvolvimento (TGD são caracterizados por anormalidades qualitativas e abrangentes em três domínios do desenvolvimento: interação social recíproca, comunicação e presença de um repertório comportamental de interesses restritos, repetitivo e estereotipado. Estudos genéticos têm identificado a recorrência de TGD numa mesma família. O presente estudo teve por objetivo rastrear a ocorrência de sinais e sintomas de TGD em irmãos de indivíduos com esse diagnóstico. Participaram do estudo 25 sujeitos provenientes de 19 famílias. A coleta de dados foi realizada mediante a utilização da versão brasileira do Autism Screening Questionnaire (ASQ, ou Questionário de Comportamento e Comunicação Social. Foram confirmados dois casos de irmãos com TGD (10,52% dos casos, sendo um irmão gêmeo monozigótico e um irmão de um probando com diagnóstico de síndrome de Asperger. Os dados apontam para taxas mais elevadas do que aquelas descritas na literatura (2-6% e se aproximam dos achados que relatam 10% de recorrência familiar em gêmeos dizigóticos. Esse resultado fornece evidências de possíveis fatores neurogenéticos para explicar a ocorrência de TGD nos familiares dos probandos estudados e salienta a necessidade de efetuar o rastreamento desse transtorno não só na criança avaliada, mas também em seus irmãos.Pervasive developmental disorders (PDD are characterized by comprehensive and qualitative abnormalities affecting three areas of development: reciprocal social interaction, communication, and a repetitive, stereotyped behavioral repertoire, of limited interests. Genetic studies have identified the recurrence of PDD in the same family. The present study aimed to trace the occurrence of signs and symptoms of PDD in the siblings of patients with this diagnosis. The study included 25 subjects from 19 families. Data collection was performed using the Brazilian version of the Autism Screening

    • When You Are a Twin or Triplet

      Science.gov (United States)

      ... be a twin? Are you a twin and wonder why everyone thinks it's so special? It's fascinating ... the way the egg is fertilized when a woman becomes pregnant . In fraternal twins, two different eggs ...

    • Behavioral problems of siblings of epileptic children in Enugu

      African Journals Online (AJOL)

      2011-02-21

      Feb 21, 2011 ... children's epilepsy has affected their healthy siblings in our own center. ... Information on the behavior of the school-age siblings and control was ... illness, for example, sickle cell disease, diabetes mellitus or epilepsy.

    • The Lived Experience of Losing a Sibling through Murder

      African Journals Online (AJOL)

      denise

      loss through homicide intensifies the grief reactions ... Bereavement related to the loss of a sibling is thought .... reaction upon hearing of their sibling's death. ...... ready to say goodbye: Surviving, coping and healing after the sudden death.

    • Weismann-Netter-Stuhl syndrome in two siblings.

      Science.gov (United States)

      Yekeler, Ensar; Ozdemir, Candan; Gokalp, Selman; Yildirim, Abdurrahman; Bas, Firdevs; Gunoz, Hulya; Acunas, Gulden

      2005-03-01

      Cases of Weismann-Netter-Stuhl syndrome involving the upper extremities and affecting siblings have rarely been reported. We present the radiological findings of Weismann-Netter-Stuhl syndrome in two siblings, with upper extremity involvement in one of them.

    • A nonmerohedral twin of methyl 2-[methyl(methylsulfonylamino]benzoate

      Directory of Open Access Journals (Sweden)

      Muhammad Shafiq

      2009-10-01

      Full Text Available The asymmetric unit of the title compound, C10H13NO4S, comprises two crystallographically independent molecules. The crystal structure is stabilized by weak intermolecular C—H...O hydrogen bonds, which link molecules along the b axis. The crystal is a nonmerohedral twin, the refined ratio of the twin components being 0.344 (2:0.656 (2.

    • Delayed Interval Delivery following Early Loss of the Leading Twin

      Directory of Open Access Journals (Sweden)

      P. C. Udealor

      2015-01-01

      Full Text Available This was a case of a nulliparous woman with reduced chance of conception following unilateral salpingectomy and years of infertility. She eventually conceived following ovulation induction resulting in twin pregnancy. She had miscarriage that led to loss of one of the twins at 17 weeks of gestational age. The pregnancy was however continued for 116 days following meticulous management with eventual delivery of a live female baby with good outcome.

    • Terpenoid variations within and among half-sibling avocado trees, Persea americana Mill. (Lauraceae).

      Science.gov (United States)

      Niogret, Jerome; Epsky, Nancy D; Schnell, Raymond J; Boza, Edward J; Kendra, Paul E; Heath, Robert R

      2013-01-01

      Chemical analyses were conducted to determine the qualitative and quantitative differences in monoterpenes and sesquiterpenes in plant material from avocado trees, Persea americana Mill. (Lauraceae). The initial study analyzed plant material sampled from the trunk to the leaves through different branch diameters to quantify proximo-distal spatial differences within a tree. All trees were seedlings initiated from a single maternal tree. Two-way analysis of variance was conducted on 34 chemicals that comprised at least 3% of the total chemical content of at least one tree and/or location within a tree. There were significant interactions between genotype and location sampled for most chemicals. Parentage analysis using microsatellite molecular markers (SSR's) determined that the four trees had three fathers and that they represented two full-siblings and two half-sibling trees. Descriptive discriminant analysis found that both genotype and location within a tree could be separated based on chemical content, and that the chemical content from full-siblings tended to be more similar than chemical content from half-siblings. To further explore the relationship between genetic background and chemical content, samples were analyzed from leaf material from 20 trees that included two sets of full-sibling seedling trees, the maternal tree and the surviving paternal tree. Descriptive discriminant analysis found good separation between the two full-sibling groups, and that the separation was associated with chemistry of the parental trees. Six groups of chemicals were identified that explained the variation among the trees. We discuss the results in relation to the discrimination process used by wood-boring insects for site-selection on host trees, for tree selection among potential host trees, and the potential use of terpenoid chemical content in chemotaxonomy of avocado trees.

    • PROGERIA IN SIBLINGS: A RARE CASE REPORT

      Science.gov (United States)

      Sowmiya, R; Prabhavathy, D; Jayakumar, S

      2011-01-01

      Progeria, also known as Hutchinson-Gilford syndrome, is an extremely rare, severe genetic condition wherein symptoms resembling aspects of aging are manifested at an early age. It is an autosomal dominant disorder. It is not seen in siblings of affected children although there are very few case reports of progeria affecting more than one child in a family. Here we are presenting two siblings, a 14-year-old male and a 13-year-old female with features of progeria, suggesting a possible autosomal recessive inheritance. PMID:22121285

    • Progeria in siblings: A rare case report

      OpenAIRE

      Sowmiya, R; Prabhavathy, D; S Jayakumar

      2011-01-01

      Progeria, also known as Hutchinson-Gilford syndrome, is an extremely rare, severe genetic condition wherein symptoms resembling aspects of aging are manifested at an early age. It is an autosomal dominant disorder. It is not seen in siblings of affected children although there are very few case reports of progeria affecting more than one child in a family. Here we are presenting two siblings, a 14-year-old male and a 13-year-old female with features of progeria, suggesting a possible autosoma...

    • Contemporary management of complicated monochorionic twins.

      Science.gov (United States)

      Moise, Karen Y; Kugler, Lisa; Jones, Tyra

      2012-01-01

      Monochorionic twins are at increased risk for unique complications including twin-twin transfusion syndrome (TTTS), selective intrauterine growth restriction (sIUGR), and twin-reversed arterial perfusion (TRAP) sequence. Twin-twin transfusion syndrome is treated with laser photocoagulation whereas selective reduction is an option in previable sIUGR or TRAP sequence. The nurse is integral in the management, education, care and support of women with complicated pregnancies. © 2012 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses.

  1. A genome-wide scan for Eysenckian personality dimensions in adolescent twin sibships: psychoticism, extraversion, neuroticism, and lie.

    Science.gov (United States)

    Gillespie, Nathan A; Zhu, Gu; Evans, David M; Medland, Sarah E; Wright, Margie J; Martin, Nick G

    2008-12-01

    We report the first genome-wide scan of adolescent personality. We conducted a genome-wide scan to detect linkage for measures of adolescent Psychoticism, Extraversion, Neuroticism, and Lie from the Junior Eysenck Personality Questionnaire. Data are based on 1,280 genotyped Australian adolescent twins and their siblings. The highest linkage peaks were found on chromosomes 16 and 19 for Neuroticism, on chromosomes 1, 7, 10, 13 m, and 18 for Psychoticism, and on chromosomes 2 and 3 for Extraversion.

  2. Growing Up without Siblings and Adult Sociability Behaviors

    Science.gov (United States)

    Trent, Katherine; Spitze, Glenna

    2011-01-01

    The authors use data from the National Survey of Families and Households to examine a range of sociability behaviors for adults who grew up with and without siblings. Compared with adults who grew up with siblings, adults who grew up without siblings have less frequent social activities with relatives, and the difference is greater among those who…

  3. Review of Sibling Interventions with Children with Autism

    Science.gov (United States)

    Banda, Devender R.

    2015-01-01

    Fifteen intervention studies were reviewed that included children with autism and their typical siblings. Overall, results across several studies reveal that siblings can have positive impacts on social and communication skills in children with autism. However, methodological variations and mixed results in studies that included siblings as…

  4. Forgotten family members: the importance of siblings in early psychosis.

    Science.gov (United States)

    Bowman, Siann; Alvarez-Jimenez, Mario; Wade, Darryl; McGorry, Patrick; Howie, Linsey

    2014-08-01

    This paper reviews the evidence on the significance of sibling inclusion in family interventions and support during early psychosis. This narrative review presents the current research related to the importance of family work during early psychosis, the needs and developmental significance of siblings during adolescence and early adulthood, the protective effects of sibling relationships, and the characteristics of early psychosis relevant to the sibling experience. It will also review the evidence of the sibling experience in chronic physical illness and disability, as well as long-term psychotic illness. Despite the evidence that working with families is important during early psychosis, siblings have been largely ignored. Siblings are an important reciprocal relationship of long duration. They play an important role in development during adolescence and early adulthood. These relationships may be an underutilized protective factor due to their inherent benefits and social support. Developmental theories imply that early psychosis could negatively impact the sibling relationship and their quality of life, effecting personality development and health outcomes. The evidence shows that adolescent physical illness or disability has a significantly negative impact on the sibling's quality of life and increases the risk for the onset of mental health issues. Long-term psychotic illness also results in negative experiences for siblings. Current evidence shows that siblings in early psychosis experience psychological distress and changes in functional performance. Further research using standard measures is required to understand the impact early psychosis has on the sibling relationship and their quality of life. © 2013 Wiley Publishing Asia Pty Ltd.

  5. Siblings, Language, and False Belief in Low-Income Children

    Science.gov (United States)

    Tompkins, Virginia; Farrar, M. Jeffrey; Guo, Ying

    2013-01-01

    The authors examined the relationship between number of siblings and false belief understanding (FBU) in 94 low-income 4-5-year-olds. Previous research with middle-income children has shown a positive association between number of siblings and FBU. However, it is unclear whether having multiple siblings in low-income families is related to better…

  6. Siblings within Families: Levels of Analysis and Patterns of Influence

    Science.gov (United States)

    Jenkins, Jennifer; Dunn, Judy

    2009-01-01

    The study of siblings has become increasingly central to developmental science. Sibling relationships have unique effects on development, and sibling designs allow researchers to isolate causal mechanisms in development. This volume emphasizes causal mechanisms in the social domain. We review the preceding chapters in relation to six topics: a…

  7. Siblings of Oedipus: Brothers and Sisters of Incest Victims.

    Science.gov (United States)

    de Young, Mary

    1981-01-01

    Investigates the roles and problems of siblings of incest victims, describes the dynamics of the incestuous family, and identifies some behavior problems of children whose siblings were incest victims. Data from two siblings' lives are presented to illustrate points. (Author/DB)

  8. Influence of Older Siblings on Initiation of Sexual Intercourse.

    Science.gov (United States)

    Widmer, Eric D.

    1997-01-01

    Examines whether older siblings (as orientational others) influence the timing of younger siblings' first intercourse. Results, based on 183 pairs of independent interviews, indicate that older brothers' sexual behavior has a significant influence on the timing of young siblings' initiation of sexual intercourse. Addresses the interaction of these…

  9. Psychological Adjustment of Siblings to a Child with Diabetes.

    Science.gov (United States)

    Hollidge, Colin

    2001-01-01

    Examines the psychological adjustment of well child siblings living with siblings with diabetes. Psychological adjustment was assessed by measuring self-concept; behavioral difficulties; competence; anxiety; and depression on standardized tests. The well siblings demonstrated significant internal psychological stressors and maintained high levels…

  10. Sibling Relationships and Influences in Childhood and Adolescence

    Science.gov (United States)

    McHale, Susan M.; Updegraff, Kimberly A.; Whiteman, Shawn D.

    2012-01-01

    The authors review the literature on sibling relationships in childhood and adolescence, starting by tracing themes from foundational research and theory and then focusing on empirical research during the past 2 decades. This literature documents siblings' centrality in family life, sources of variation in sibling relationship qualities, and the…

  11. Sibling effect on atopy in children of patients with asthma

    NARCIS (Netherlands)

    Koppelman, GH; Jansen, DF; Schouten, JP; van der Heide, S; Bleecker, ER; Meyers, DA; Postma, DS

    2003-01-01

    Background Multiple population studies have shown the presence of a sibling effect on atopic disease. However, it is unclear if the sibling effect is also of importance in subjects who are genetically at high risk for the development of atopy. Objective To study the presence of a sibling effect on m

  12. Parental divorce and sibling relationships : a research note

    NARCIS (Netherlands)

    Poortman, A.R.; Voorpostel, M.B.J.

    2009-01-01

    This study examines long-term effects of parental divorce on sibling relationships in adulthood and the role of predivorce parental conflict. It used large-scale retrospective data from the Netherlands that contain reports from both siblings of the sibling dyad. Results show limited effects of

  13. Sibling Relationships and Influences in Childhood and Adolescence

    Science.gov (United States)

    McHale, Susan M.; Updegraff, Kimberly A.; Whiteman, Shawn D.

    2012-01-01

    The authors review the literature on sibling relationships in childhood and adolescence, starting by tracing themes from foundational research and theory and then focusing on empirical research during the past 2 decades. This literature documents siblings' centrality in family life, sources of variation in sibling relationship qualities, and the…

  14. Parental divorce and sibling relationships : a research note

    NARCIS (Netherlands)

    Poortman, A.R.; Voorpostel, M.B.J.

    2009-01-01

    This study examines long-term effects of parental divorce on sibling relationships in adulthood and the role of predivorce parental conflict. It used large-scale retrospective data from the Netherlands that contain reports from both siblings of the sibling dyad. Results show limited effects of paren

  15. Factors Related to Sibling Removal after a Child Maltreatment Fatality

    Science.gov (United States)

    Damashek, Amy; Bonner, Barbara L.

    2010-01-01

    Objectives: Many children who die from abuse or neglect are survived by siblings. However, little data are available about what happens to these siblings after the victim's death, such as whether they are removed from their home. Even less is known about how decisions are made regarding sibling removal following a child fatality. This study…

  16. Twinning and heteropaternity in chimpanzees (Pan troglodytes).

    Science.gov (United States)

    Ely, John J; Frels, William I; Howell, Sue; Izard, M Kay; Keeling, Michale E; Lee, D Rick

    2006-05-01

    Unlike monozygotic (MZ) twins, dizygotic (DZ) twins develop from separate ova. The resulting twins can have different sires if the fertilizing sperm comes from different males. Routine paternity testing of a pair of same-sexed chimpanzee twins born to a female housed with two males indicated that the twins were sired by two different males. DNA typing of 22 short-tandem repeat (STR) loci demonstrated that these twins were not MZ twins but heteropaternal DZ twins. Reproductive data from 1926-2002 at five domestic chimpanzee colonies, including 52 twins and two triplets in 1,865 maternities, were used to estimate total twinning rates and the MZ and DZ components. The average chimpanzee MZ twinning rate (0.43%) equaled the average human MZ rate (0.48%). However, the chimpanzee DZ twinning rate (2.36%) was over twice the human average, and higher than all but the fertility-enhanced human populations of Nigeria. Similarly high twinning rates among African chimpanzees indicated that these estimates were not artifacts of captivity. Log-linear analyses of maternal and paternal effects on recurrent twinning indicated that females who twinned previously had recurrence risks five times greater than average, while evidence for a paternal twinning effect was weak. Chimpanzee twinning rates appear to be elevated relative to corresponding estimated human rates, making twinning and possibly heteropaternity more important features of chimpanzee reproductive biology than previously recognized.

  17. Twin Legacies: Victor and Vincent McKusick/Twin Studies: Twinning Rates I; Twinning Rates II; MZ Twin Discordance for Russell-Silver Syndrome; Twins' Language Skills/Headlines: Babies Born to Identical Twin Couples; Identity Exchange; Death of Princess Ashraf (Twin); Yahoo CEO Delivers Identical Twins.

    Science.gov (United States)

    Segal, Nancy L

    2016-04-01

    The lives of the illustrious monozygotic (MZ) twins, Victor A. and Vincent L. McKusick, are described. Victor earned the distinction as the 'Father of Medical Genetics', while Vincent was a legendary Chief Justice of the Maine Supreme Court. This dual biographical account is followed by two timely reports of twinning rates, a study of MZ twin discordance for Russell-Silver Syndrome (RSS) and a study of twins' language skills. Twin stories in the news include babies born to identical twin couples, a case of switched identity, the death of Princess Ashraf (Twin) and a new mother of twins who is also Yahoo's CEO.

  18. Estimating twin concordance for bivariate competing risks twin data

    DEFF Research Database (Denmark)

    Scheike, Thomas Harder; Holst, Klaus Kähler; von Bornemann Hjelmborg, Jacob

    2014-01-01

    For twin time-to-event data, we consider different concordance probabilities, such as the casewise concordance that are routinely computed as a measure of the lifetime dependence/correlation for specific diseases. The concordance probability here is the probability that both twins have experienced...... over time, and covariates may be further influential on the marginal risk and dependence structure. We establish the estimators large sample properties and suggest various tests, for example, for inferring familial influence. The method is demonstrated and motivated by specific twin data on cancer...... the event of interest. Under the assumption that both twins are censored at the same time, we show how to estimate this probability in the presence of right censoring, and as a consequence, we can then estimate the casewise twin concordance. In addition, we can model the magnitude of within pair dependence...

  19. Relational Aggression in Preschool Students: An Exploration of the Variables of Sex, Age, and Siblings

    Directory of Open Access Journals (Sweden)

    Karen A. Morine

    2011-01-01

    Full Text Available In this study, researchers wished to ascertain whether there were age (three- and four-year old, sibling (with or without older siblings, and sex (male and female differences in the use of relational aggression in preschool students as rated by peers and teachers. In order to answer this research question, two 2 × 2 × 2 factorial ANOVA procedures with the relational aggression composite score as the dependent variable on the PSBS-P and PSBS-T were used for peer and teacher assessment, respectively, of relational aggression. Results revealed that in the peer ratings of preschool students' relationally aggressive behavior, there was an disordinal age by sibling interaction, in which four-year-old children with siblings were significantly more likely to be rated by their peers as using relational aggression than three-year-old children without siblings. In the teacher ratings of preschool students' relationally aggressive behavior, a main effect for age was observed. Teachers rated four-year old children as evidencing significantly higher levels of relational aggression as compared to three-year-olds. No sex differences were observed in the use of relational aggression either at age three or age four in this sample. Implications for these findings are presented.

  20. Assessment of Serum Zinc Levels of Patients with Thalassemia Compared to Their Siblings

    Directory of Open Access Journals (Sweden)

    Mohamed El Missiry

    2014-01-01

    Full Text Available Zinc (Zn is essential for appropriate growth and proper immune function, both of which may be impaired in thalassemia children. Factors that can affect serum Zn levels in these patients may be related to their disease or treatment or nutritional causes. We assessed the serum Zn levels of children with thalassemia paired with a sibling. Zn levels were obtained from 30 children in Islamabad, Pakistan. Serum Zn levels and anthropometric data measures were compared among siblings. Thalassemia patients’ median age was 4.5 years (range 1–10.6 years and siblings was 7.8 years (range 1.1–17 years. The median serum Zn levels for both groups were within normal range: 100 μg/dL (10 μg/dL–297 μg/dL for patients and 92 μg/dL (13 μg/dL–212 μg/dL for siblings. There was no significant difference between the two groups. Patients’ serum Zn values correlated positively with their corresponding siblings (r=0.635, P<0.001. There were no correlations between patients’ Zn levels, height for age Z-scores, serum ferritin levels, chelation, or blood counts (including both total leukocyte and absolute lymphocyte counts. Patients’ serum Zn values correlated with their siblings’ values. In this study, patients with thalassemia do not seem to have disease-related Zn deficiency.

  1. Presenting Twins Are Exposed to Higher Levels of Inflammatory Mediators than Nonpresenting Twins as Early as the Midtrimester of Pregnancy.

    Directory of Open Access Journals (Sweden)

    Seung Mi Lee

    Full Text Available Presenting twins are less likely to develop respiratory complications than non-presenting twins. The precise reason for this difference is not well understood, although it is known that the presence of inflammation reduces the risk of respiratory morbidity at birth. To further investigate this association, we compared the concentrations of inflammatory biomarkers in mid-trimester amniotic fluid (AF of asymptomatic twin pairs.The study population consisted of women with twin pregnancies who underwent mid-trimester amniocentesis (15-20 weeks for routine clinical indications and delivered at term. AF was analyzed for pro-inflammatory cytokines (IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, IL-13, IL-15, IFN-γ, TNF-α, matrix metalloproteinases (MMP-1, MMP-2, MMP-3, MMP-8, MMP-9, MMP-12, and chemokines (Complement Factor D/Adipsin, Serpin E1/PAI-1, Adiponectin/Acrp30, CRP, CCL2/MCP-1, Leptin, Resistin using Luminex Performance Assay multiplex kits. Data were analyzed using Wilcoxon signed rank test.A total of 82 twin pairs were enrolled. Mid-trimester AF concentrations of IL-8, MMP-8, CRP, MCP-1, leptin, and resistin were significantly higher in the presenting twin compared with the non-presenting twin (p<0.05 for each. Differences in AF concentrations of IL-8, MMP-8, and CRP persisted after adjustment for the fetal growth restriction at the time of birth and chorionicity.These data suggest that, as early as the mid-trimester, the presenting fetus in an otherwise uncomplicated twin pregnancy is exposed to higher levels of pro-inflammatory mediators (especially IL-8, MMP-8, and CRP than its non-presenting co-twin. Whether this pro-inflammatory milieu reduces the risk of neonatal respiratory morbidity at birth or has other functional implications needs to be further evaluated.

  2. Confronting Twin Paradox Acceleration

    Science.gov (United States)

    Murphy, Thomas W.

    2016-05-01

    The resolution to the classic twin paradox in special relativity rests on the asymmetry of acceleration. Yet most students are not exposed to a satisfactory analysis of what exactly happens during the acceleration phase that results in the nonaccelerated observer's more rapid aging. The simple treatment presented here offers both graphical and quantitative solutions to the problem, leading to the correct result that the acceleration-induced age gap is 2Lβ years when the one-way distance L is expressed in light-years and velocity β ≡v/c .

  3. Holographic twin Higgs model.

    Science.gov (United States)

    Geller, Michael; Telem, Ofri

    2015-05-15

    We present the first realization of a "twin Higgs" model as a holographic composite Higgs model. Uniquely among composite Higgs models, the Higgs potential is protected by a new standard model (SM) singlet elementary "mirror" sector at the sigma model scale f and not by the composite states at m_{KK}, naturally allowing for m_{KK} beyond the LHC reach. As a result, naturalness in our model cannot be constrained by the LHC, but may be probed by precision Higgs measurements at future lepton colliders, and by direct searches for Kaluza-Klein excitations at a 100 TeV collider.

  4. Oliver Sacks: Our Correspondence About Twins/Twin Research: Vanishing Twins Syndrome; Discordant Sex in MZ Twins; Pregnancy Outcomes in IVF and ICSI Conceived Twins/Print and Media: Superfetated Twins; Twins Discordant for Smoking; Twins in Fashion; Yale University Twin Hockey Players; Conjoined Twin-Visiting Professor.

    Science.gov (United States)

    Segal, Nancy L

    2017-08-01

    The late neurologist and author, Oliver Sacks, published an insightful 1986 review of Marjorie Wallace's book, The Silent Twins, in the New York Times. Taking exception to his assertion about Sir Francis Galton, I wrote a letter to the Times' editor. The letter was unpublished, but it brought a wonderful response from Sacks himself that is reproduced and examined. Next, brief reviews of twin research concerning the vanishing twin syndrome (VTS), discordant sex in a monozygotic (MZ) twin pair, and multiple pregnancy outcomes from assisted reproductive technology (ART) are presented. This section is followed by popular coverage of superfetated twins, smoking-discordant co-twins, twins in fashion, Yale University twin hockey players, and a visiting professor who was a conjoined twin.

  5. Sibling recognition and the development of identity: intersubjective consequences of sibling differentiation in the sister relationship.

    Science.gov (United States)

    Vivona, Jeanine M

    2013-01-01

    Identity is, among other things, a means to adapt to the others around whom one must fit. Psychoanalytic theory has highlighted ways in which the child fits in by emulating important others, especially through identification. Alternately, the child may fit into the family and around important others through differentiation, an unconscious process that involves developing or accentuating qualities and desires in oneself that are expressly different from the perceived qualities of another person and simultaneously suppressing qualities and desires that are perceived as similar. With two clinical vignettes centered on the sister relationship, the author demonstrates that recognition of identity differences that result from sibling differentiation carries special significance in the sibling relationship and simultaneously poses particular intersubjective challenges. To the extent that the spotlight of sibling recognition delimits the lateral space one may occupy, repeatedly frustrated desires for sibling recognition may have enduring consequences for one's sense of self-worth and expectations of relationships with peers and partners.

  6. Transformation: From Twin to Individual

    Science.gov (United States)

    Magagna, Jeanne

    2007-01-01

    This article explores some of the complexities of psychotherapy with an identical twin. The difficulty of developing in psychotherapy while so much of what is oneself is located in the other twin will also be explored. The use of the countertransference as a therapeutic method will be considered as the young person develops her unique, separate…

  7. Twin Studies of Atopic Dermatitis

    DEFF Research Database (Denmark)

    Elmose, Camilla; Thomsen, Simon Francis

    2015-01-01

    Aim. The aim of this study was to conduct a systematic review of population-based twin studies of (a) the concordance and heritability of AD and (b) the relationship between AD and asthma and, furthermore, to reinterpret findings from previous twin studies in the light of the emerging knowledge a...

  8. Twin methodology in epigenetic studies

    DEFF Research Database (Denmark)

    Tan, Qihua; Christiansen, Lene; von Bornemann Hjelmborg, Jacob

    2015-01-01

    Since the final decades of the last century, twin studies have made a remarkable contribution to the genetics of human complex traits and diseases. With the recent rapid development in modern biotechnology of high-throughput genetic and genomic analyses, twin modelling is expanding from analysis ...

  9. Twin Higgs WIMP Dark Matter

    CERN Document Server

    García, Isabel García; March-Russell, John

    2015-01-01

    Dark matter (DM) without a matter asymmetry is studied in the context of Twin Higgs (TH) theories in which the LHC naturalness problem is addressed. These possess a twin sector related to the Standard Model (SM) by a (broken) $\\mathbb{Z}_2$ symmetry, and interacting with the SM via a specific Higgs portal. We focus on the minimal realisation of the TH mechanism, the Fraternal Twin Higgs, with only a single generation of twin quarks and leptons, and $SU(3)'\\times SU(2)'$ gauge group. We show that a variety of natural twin-WIMP DM candidates are present (directly linked to the weak scale by naturalness), the simplest and most attractive being the $\\tau^\\prime$ lepton with a mass $m_{\\tau^\\prime} > m_{\\rm Higgs}/2$, although spin-1 $W^{\\prime\\pm}$ DM and multicomponent DM are also possible (twin baryons are strongly disfavoured by tuning). We consider in detail the dynamics of the possibly (meta)stable glueballs in the twin sector, the nature of the twin QCD phase transition, and possible new contributions to th...

  10. Hypertensive disorders in twin pregnancy

    NARCIS (Netherlands)

    J.G. Santema (Job); E. Koppelaar (Elin); H.C.S. Wallenburg (Henk)

    1995-01-01

    textabstractObjective: To compare the incidence and severity of pregnancy-induced hypertensive disorders in twin pregnancy and in singleton gestation. Study design: Case-control study in the setting of a University Hospital. Each pregnancy of a consecutive series of 187 twin pregnancies attending th

  11. Dicephalus parapagus conjoined twins discordant for anencephaly: a case report

    Directory of Open Access Journals (Sweden)

    Udo Jacob J

    2010-02-01

    Full Text Available Abstract Introduction Cases of conjoined twins occur so rarely that it is important to learn as much as possible from each case. Case presentation We present a case of 9-hour-old, female, Nigerian dicephalus parapagus conjoined twins discordant for anencephaly diagnosed only after the birth of the twins. The anencephalic twin was stillborn while the normal one died within 9 hours of birth from cardiopulmonary failure. Conclusion Many congenital defects of interest can now be detected before birth. A severe lesion such as that found in our index case, which is incompatible with postnatal life, requires counselling. If detected early enough during a properly monitored antenatal care, it may indicate termination of pregnancy.

  12. Psychosocial Adjustment and Sibling Relationships in Siblings of Children with Autism Spectrum Disorder: Risk and Protective Factors

    Science.gov (United States)

    Walton, Katherine M.; Ingersoll, Brooke R.

    2015-01-01

    This study compared sibling adjustment and relationships in siblings of children with Autism Spectrum Disorder (ASD-Sibs; n = 69) and siblings of children with typical development (TD-Sibs; n = 93). ASD-Sibs and TD-Sibs demonstrated similar emotional/behavioral adjustment. Older male ASD-Sibs were at increased risk for difficulties. Sibling…

  13. Family Perspectives on Siblings' Conflict Goals in Middle Childhood: Links to Hierarchical and Affective Features of Sibling Relationships

    Science.gov (United States)

    Recchia, Holly E.; Witwit, Ma-ab

    2017-01-01

    This study examined parents' and children's descriptions of older and younger siblings' conflict goals in the late preschool and middle childhood years, and how these attributions were related to sibling relationship quality. Parents and 4- to 10-year-old children from 62 families were interviewed separately about siblings' motivations in two…

  14. Psychological Adjustment and Sibling Relationships in Siblings of Children with Autism Spectrum Disorders: Environmental Stressors and the Broad Autism Phenotype

    Science.gov (United States)

    Petalas, Michael A.; Hastings, Richard P.; Nash, Susie; Hall, Louise M.; Joannidi, Helen; Dowey, Alan

    2012-01-01

    Research with siblings of children with Autism Spectrum Disorders (ASD) suggests that they may be at increased risk for behavioural and emotional problems and relatively poor sibling relationships. This study investigated a diathesis-stress model, whereby the presence of Broad Autism Phenotype features in the typically developing siblings might…

  15. Adolescent Sibling Relationship Quality and Adjustment: Sibling Trustworthiness and Modeling, as Factors Directly and Indirectly Influencing These Associations

    Science.gov (United States)

    Gamble, Wendy C.; Yu, Jeong Jin; Kuehn, Emily D.

    2011-01-01

    The main goal of this study was to examine the direct and moderating effects of trustworthiness and modeling on adolescent siblings' adjustment. Data were collected from 438 families including a mother, a younger sibling in fifth, sixth, or seventh grade (M = 11.6 years), and an older sibling (M = 14.3 years). Respondents completed Web-based…

  16. Life Span Personality Stability in Sibling Statuses.

    Science.gov (United States)

    Rosenberg, B. G.

    Personality stability and change in sibling status in the one- and two-child-family are examined in this Study. Q-sort data were analyzed for the same 33 male and 34 female subjects during four periods of their lives-- early and late adolescence and early and middle adulthood. Results indicate that stability of personality was greatest during…

  17. Modeling confounding by half-sibling regression

    DEFF Research Database (Denmark)

    Schölkopf, Bernhard; Hogg, David W; Wang, Dun

    2016-01-01

    We describe a method for removing the effect of confounders to reconstruct a latent quantity of interest. The method, referred to as "half-sibling regression," is inspired by recent work in causal inference using additive noise models. We provide a theoretical justification, discussing both...

  18. Multiple gastrointestinal atresias in two consecutive siblings.

    Science.gov (United States)

    Gahukamble, D B; Gahukamble, L D

    2002-03-01

    Two consecutive female siblings with multiple gastrointestinal atresias are described. The history of consanguinity in the parents and the presence of extensive typical pathological lesions suggest a genetically-induced developmental fault in the alimentary tract during the early embryonic period.

  19. A Computational Discriminability Analysis on Twin Fingerprints

    Science.gov (United States)

    Liu, Yu; Srihari, Sargur N.

    Sharing similar genetic traits makes the investigation of twins an important study in forensics and biometrics. Fingerprints are one of the most commonly found types of forensic evidence. The similarity between twins’ prints is critical establish to the reliability of fingerprint identification. We present a quantitative analysis of the discriminability of twin fingerprints on a new data set (227 pairs of identical twins and fraternal twins) recently collected from a twin population using both level 1 and level 2 features. Although the patterns of minutiae among twins are more similar than in the general population, the similarity of fingerprints of twins is significantly different from that between genuine prints of the same finger. Twins fingerprints are discriminable with a 1.5%~1.7% higher EER than non-twins. And identical twins can be distinguished by examine fingerprint with a slightly higher error rate than fraternal twins.

  20. Purging putative siblings from population genetic data sets: a cautionary view.

    Science.gov (United States)

    Waples, Robin S; Anderson, Eric C

    2017-03-01

    Interest has surged recently in removing siblings from population genetic data sets before conducting downstream analyses. However, even if the pedigree is inferred correctly, this has the potential to do more harm than good. We used computer simulations and empirical samples of coho salmon to evaluate strategies for adjusting samples to account for family structure. We compared performance in full samples and sibling-reduced samples of estimators of allele frequency (P^), population differentiation (F^ST) and effective population size (N^e).

  1. Survival advantage of siblings and spouses of centenarians in 20th-century Quebec

    Directory of Open Access Journals (Sweden)

    Valérie Jarry

    2013-02-01

    Full Text Available Longevity runs in families, either through genetic or environmental influences. Using Quebec civil registration and historical Canadiancensuses, we compared the longevity of siblings and spouses of 806 centenarians to a group of controls, all born in Quebec at the turnof the 20th century. Our results show that siblings of centenarians, who share half of their genes and a common childhood environment,lived 3–4 years longer than their birth cohort. However, husbands and wives of centenarians lived 4 and 2.5 years longer than theircounterparts of the same sex, respectively, suggesting that longevity is also modulated by shared environment in adulthood.

  2. Megalencephalic leukoencephalopathy with subcortical cysts in all three siblings of a non-Aggarwal Indian family

    Directory of Open Access Journals (Sweden)

    Mani Kant Kumar

    2012-01-01

    Full Text Available Megalencephalic leukoencephalopathy with subcortical cysts (MLC is a rare neurodegenerative disease seen mainly in the Aggarwal community in India. It is characterized by early-onset macrocephaly with mild motor developmental delay, gradual onset ataxia, spasticity, seizures and usually late onset mild cognitive deterioration. Very few familial cases of MLC have been reported in the world literature, and to the best of our knowledge, there is no published study of all three siblings affected with MLC in a same family. Here, we are reporting three siblings belonging to a non-Aggarwal Hindu family, affected with MLC, who presented with early-onset macrocephaly and gradual onset ataxia.

  3. Dramatically different dizygotic twins: will we include them in Research? Twin research reviews: congenital anomalies, mirror-image effects in conjoined twins, older mothers of twins; Twin statistics: 'Massachusetts, land of twins'; Tribute: Dr Victor A. McKusick.

    Science.gov (United States)

    Segal, Nancy L

    2008-10-01

    The increased frequency of interracial marriage is a likely source of unusual-looking dizygotic (DZ) twins. Some members of DZ twin pairs born to mixed-race couples inherit very different physical features from their parents. This raises several questions, such as: Will researchers wish to include such twins in their ongoing studies? Next, new twin research concerned with congenital anomalies, mirror-image effects in conjoined twins and older mothers of twins will be reviewed. New statistics on twinning rates in Massachusetts will also be summarized, followed by a tribute to the late medical geneticist Dr. Victor A. McKusick.

  4. LEISURE-TIME PHYSICAL ACTIVITY IN LATE ADOLESCENCE: A Cohort Study of Stability, Correlates and Familial Aggregation in Twin Boys and Girls

    Directory of Open Access Journals (Sweden)

    Marja Aarnio

    2003-09-01

    Full Text Available Regular exercise has been shown to exert many positive effects on health. Sedentary behaviour often originates in childhood and many common adult chronic diseases are related to inactivity. Adolescent physical activity patterns and health habits are important subjects to study because of the known associations of physical activity with other health habits and the evidence that these associations track into adulthood. The data for this study were gathered as a part of FinnTwin16, a longitudinal study of five consecutive birth cohorts of Finnish twins, their siblings and parents. The study material was collected by identifying twins born in 1975-1979. Questionnaires concerning leisure-time physical activity, health-related behaviours, social relationship and health status were sent to twins on their 16th and 17th birthdays, and six months after their 18th. The maximal cohort size was 4906 boys and girls, and the response rate 75.8% to 81.7%. The results of this study reveal that persistently active adolescents smoked less than inactive ones, and usually had better health and nutritional habits, such as use of spreads and regular breakfast eating, and better self-estimated health. They attended high schools rather than vocational schools and tended to have better academic achievement. Participating in organised sport, in many different types of sport, or in power sports and ball games were also associated with persistent physical activity. Parents' and grandparents' physical activity were not associated with adolescent physical activity except in the case of very active mothers and daughters, but a co-twin's physical activity was associated. There was a gender difference in physical activity patterns: boys were more active than girls. No gender difference was found in health related-behaviours, except that girls reported more psychosomatic symptoms such as tension, in the low physical activity categories than boys. The known health benefits of

  5. Sibling Position and Risk Attitudes: Is Being an Only Child Associated with a Person’s Risk Tolerance?

    Directory of Open Access Journals (Sweden)

    Jennifer M. Brown

    2014-12-01

    Full Text Available The influence of birth order on personality has been studied for several decades, but little research has been conducted on the association between sibling position and risk tolerance. The purpose of this study was to examine the relationship between being an only child and risk-taking attitudes. Data from the 2010 National Longitudinal Survey of Youth, 1979 sample was used to test the hypotheses that only children and first borns are similar, only children exhibit a lower risk tolerance when compared to those with siblings, and only children exhibit a lower risk tolerance when compared to those with siblings when first borns are removed and only borns are compared with later borns. Results did show that only children are similar to first borns in nearly every domain of risk tolerance considered. Furthermore, they do not exhibit dramatically different risk attitudes than those with siblings when the variables of sex, locus of control, and net worth are controlled.

  6. Separation of thoraco-omphalopagus twins in a rural secondary hospital: Perioperative management

    Directory of Open Access Journals (Sweden)

    Madhurita Singh

    2012-01-01

    Full Text Available Providing anaesthesia for the separation surgery of conjoined twins presents unique challenges to the managing anaesthesiologists. The low incidence of such surgeries and anatomical variations in each type of conjoined twins makes each separation surgery a unique experience. This report features the anaesthetic plan and challenges faced in performing the separation surgery of a set of thoraco-omphalopagus twins in a rural secondary hospital in a remote location in India.

  7. Impaired prefrontal hemodynamic maturation in autism and unaffected siblings.

    Directory of Open Access Journals (Sweden)

    Yuki Kawakubo

    Full Text Available BACKGROUND: Dysfunctions of the prefrontal cortex have been previously reported in individuals with autism spectrum disorders (ASD. Previous studies reported that first-degree relatives of individuals with ASD show atypical brain activity during tasks associated with social function. However, developmental changes in prefrontal dysfunction in ASD and genetic influences on the phenomena remain unclear. In the present study, we investigated the change in hemoglobin concentration in the prefrontal cortex as measured with near-infrared spectroscopy, in children and adults with ASD during the letter fluency test. Moreover, to clarify the genetic influences on developmental changes in the prefrontal dysfunction in ASD, unaffected siblings of the ASD participants were also assessed. METHODOLOGY/PRINCIPAL FINDINGS: Study participants included 27 individuals with high-functioning ASD, age- and IQ-matched 24 healthy non-affected siblings, and 27 unrelated healthy controls aged 5 to 39 years. The relative concentration of hemoglobin ([Hb] in the prefrontal cortex was measured during the letter fluency task. For children, neither the [oxy-Hb] change during the task nor task performances differed significantly among three groups. For adults, the [oxy-Hb] increases during the task were significantly smaller in the bilateral prefrontal cortex in ASD than those in control subjects, although task performances were similar. In the adult siblings the [oxy-Hb] change was intermediate between those in controls and ASDs. CONCLUSION/SIGNIFICANCE: Although indirectly due to a cross-sectional design, the results of this study indicate altered age-related change of prefrontal activity during executive processing in ASD. This is a first near-infrared spectroscopy study that implies alteration in the age-related changes of prefrontal activity in ASD and genetic influences on the phenomena.

  8. Ellis–Van Creveld syndrome in siblings: A rare case report

    Directory of Open Access Journals (Sweden)

    Sabitha Gokulraj

    2016-01-01

    Full Text Available Ellis–Van Creveld syndrome or chondroectodermal dysplasia is a rare autosomal recessive disorder presenting several skeletal manifestations and congenital heart malformations. Ellis–Van Creveld syndrome comprises of a tetrad of clinical manifestations of chondrodysplasia, polydactyly, ectodermal dysplasia, and cardiac defects. Here, we are presenting a very rare case of Ellis–Van Creveld syndrome in siblings.

  9. Idiopathic gynaecomastia in twins: a case report

    Directory of Open Access Journals (Sweden)

    S.V. Kumar

    2014-08-01

    Full Text Available Gynaecomastia is a common pathological condition of breast seen in men. This is defined as benign enlargement of breast tissue in males. It was first described by Palus Aegineta (AD 635-690. Herewith we are presenting cases of 14 year old twins attending the surgical O.P.D with bilateral enlarged breasts and pain. A diagnosis of pubertal gynaecomastia was made with no evidence of malignancy by histopathological examinations and mammography. One boy with 5 x 6 cm of right breast and 2 x3 cm of left breast was treated by subcutaneous mastectomy. Other boy had only enlargement of nipple and areola. He was reassured and sent home without surgical intervention. A rare case of idiopathic gynaecomastia in pubertal twins is described here. [Int J Res Med Sci 2014; 2(4.000: 1755-1757

  10. Education in time: cohort differences in educational attainment in African-American twins.

    Directory of Open Access Journals (Sweden)

    Sarah L Szanton

    Full Text Available OBJECTIVES: Educational opportunities for African-Americans expanded throughout the 20(th century. Twin pairs are an informative population in which to examine changes in educational attainment because each twin has the same parents and childhood socioeconomic status. We hypothesized that correlation in educational attainment of older twin pairs would be higher compared to younger twin pairs reflecting changes in educational access over time and potentially reflecting a "ceiling effect" associated with Jim Crow laws and discrimination. METHODOLOGY AND PRINCIPAL FINDINGS: We used data from 211 same-sex twin pairs (98 identical, 113 fraternal in the Carolina African-American Twin Study of Aging who were identified through birth records. Participants completed an in-person interview. The twins were predominantly female (61%, with a mean age of 50 years (SD = 0.5. We found that older age groups had a stronger intra-twin correlation of attained educational level. Further analysis across strata revealed a trend across zygosity, with identical twins demonstrating more similar educational attainment levels than did their fraternal twin counterparts, suggesting a genetic influence. DISCUSSION: These findings suggest that as educational opportunities broadened in the 20th century, African-Americans gained access to educational opportunities that better matched their individual abilities.

  11. Seasonal changes, sleep length and circadian preference among twins with bipolar disorder

    Directory of Open Access Journals (Sweden)

    Koskenvuo Markku

    2003-06-01

    Full Text Available Abstract Background We aimed at studying the seasonal changes in mood and behaviour, the distribution of hospital admissions by season, and the persistence of the circadian type in twins with bipolar disorder and their healthy co-twins. Methods All Finnish like-sex twins born from 1940 to 1969 were screened for a diagnosis of bipolar type I disorder. The diagnosis was assessed with a structured research interview, and the study subjects (n = 67 filled in the Seasonal Pattern Assessment Questionnaire (SPAQ and the Morningness-Eveningness Questionnaire (MEQ. For studying the persistence of the habitual sleep length and circadian type, we used data derived from the Finnish Twin Cohort Questionnaire (FTCQ. Bipolar twins were compared with their healthy co-twins. Results Bipolar twins had greater seasonal changes in sleep length (p = 0.01 and mood (p = 0.01, and higher global seasonality scores (p = 0.03 as compared with their co-twins with no mental disorder. Sunny days (p = 0.03 had a greater positive effect on wellbeing in the bipolar than healthy co-twins. Conclusions Our results support the view that bipolar disorder is sensitive to the environmental influence in general and to the seasonal effect in specific. Exposure to natural light appears to have a substantial effect on wellbeing in twins with bipolar disorder.

  12. Twins and Kindergarten Separation: Divergent Beliefs of Principals, Teachers, Parents, and Twins

    Science.gov (United States)

    Gordon, Lynn Melby

    2015-01-01

    Should principals enforce mandatory separation of twins in kindergarten? Do school separation beliefs of principals differ from those of teachers, parents of twins, and twins themselves? This survey questioned 131 elementary principals, 54 kindergarten teachers, 201 parents of twins, and 112 twins. A majority of principals (71%) believed that…

  13. Paternal age and telomere length in twins

    DEFF Research Database (Denmark)

    Hjelmborg, Jacob B; Dalgård, Christine; Mangino, Massimo

    2015-01-01

    . Based on two independent (discovery and replication) twin studies, comprising 889 twin pairs, we show an increase in the resemblance of leukocyte telomere length between dizygotic twins of older fathers, which is not seen in monozygotic twins. This phenomenon might result from a paternal age...

  14. Recipient twin limb ischemia with postnatal onset.

    Science.gov (United States)

    Broadbent, Roland Spencer

    2007-02-01

    After the occurrence of 3 local cases of limb ischemia in newborn twins, we reviewed the literature to investigate this combination systematically. This review reveals a distinct condition: postnatal onset limb ischemia affecting recipient twins in twin-twin transfusion syndrome.

  15. Best Practices for Twin Placement in School

    Science.gov (United States)

    Lacina, Jan

    2012-01-01

    The children's book "Two Is for Twins" celebrates twins and illustrates the many "twos" in a child's world. The uniqueness of twos does not have to mean separate classrooms for twins in child development programs, preschool, or elementary school settings. With recent dramatic increases in the US twin population, how should educators address the…

  16. Best Practices for Twin Placement in School

    Science.gov (United States)

    Lacina, Jan

    2012-01-01

    The children's book "Two Is for Twins" celebrates twins and illustrates the many "twos" in a child's world. The uniqueness of twos does not have to mean separate classrooms for twins in child development programs, preschool, or elementary school settings. With recent dramatic increases in the US twin population, how should educators address the…

  17. Twin Higgs Asymmetric Dark Matter.

    Science.gov (United States)

    García García, Isabel; Lasenby, Robert; March-Russell, John

    2015-09-18

    We study asymmetric dark matter (ADM) in the context of the minimal (fraternal) twin Higgs solution to the little hierarchy problem, with a twin sector with gauged SU(3)^{'}×SU(2)^{'}, a twin Higgs doublet, and only third-generation twin fermions. Naturalness requires the QCD^{'} scale Λ_{QCD}^{'}≃0.5-20  GeV, and that t^{'} is heavy. We focus on the light b^{'} quark regime, m_{b^{'}}≲Λ_{QCD}^{'}, where QCD^{'} is characterized by a single scale Λ_{QCD}^{'} with no light pions. A twin baryon number asymmetry leads to a successful dark matter (DM) candidate: the spin-3/2 twin baryon, Δ^{'}∼b^{'}b^{'}b^{'}, with a dynamically determined mass (∼5Λ_{QCD}^{'}) in the preferred range for the DM-to-baryon ratio Ω_{DM}/Ω_{baryon}≃5. Gauging the U(1)^{'} group leads to twin atoms (Δ^{'}-τ^{'}[over ¯] bound states) that are successful ADM candidates in significant regions of parameter space, sometimes with observable changes to DM halo properties. Direct detection signatures satisfy current bounds, at times modified by dark form factors.

  18. Twin methodology in epigenetic studies.

    Science.gov (United States)

    Tan, Qihua; Christiansen, Lene; von Bornemann Hjelmborg, Jacob; Christensen, Kaare

    2015-01-01

    Since the final decades of the last century, twin studies have made a remarkable contribution to the genetics of human complex traits and diseases. With the recent rapid development in modern biotechnology of high-throughput genetic and genomic analyses, twin modelling is expanding from analysis of diseases to molecular phenotypes in functional genomics especially in epigenetics, a thriving field of research that concerns the environmental regulation of gene expression through DNA methylation, histone modification, microRNA and long non-coding RNA expression, etc. The application of the twin method to molecular phenotypes offers new opportunities to study the genetic (nature) and environmental (nurture) contributions to epigenetic regulation of gene activity during developmental, ageing and disease processes. Besides the classical twin model, the case co-twin design using identical twins discordant for a trait or disease is becoming a popular and powerful design for epigenome-wide association study in linking environmental exposure to differential epigenetic regulation and to disease status while controlling for individual genetic make-up. It can be expected that novel uses of twin methods in epigenetic studies are going to help with efficiently unravelling the genetic and environmental basis of epigenomics in human complex diseases.

  19. The vector-like twin Higgs

    Science.gov (United States)

    Craig, Nathaniel; Knapen, Simon; Longhi, Pietro; Strassler, Matthew

    2016-07-01

    We present a version of the twin Higgs mechanism with vector-like top partners. In this setup all gauge anomalies automatically cancel, even without twin leptons. The matter content of the most minimal twin sector is therefore just two twin tops and one twin bottom. The LHC phenomenology, illustrated with two example models, is dominated by twin glueball decays, possibly in association with Higgs bosons. We further construct an explicit four-dimensional UV completion and discuss a variety of UV completions relevant for both vector-like and fraternal twin Higgs models.

  20. The Vector-like Twin Higgs

    CERN Document Server

    Craig, Nathaniel; Longhi, Pietro; Strassler, Matthew

    2016-01-01

    We present a version of the twin Higgs mechanism with vector-like top partners. In this setup all gauge anomalies automatically cancel, even without twin leptons. The matter content of the most minimal twin sector is therefore just two twin tops and one twin bottom. The LHC phenomenology, illustrated with two example models, is dominated by twin glueball decays, possibly in association with Higgs bosons. We further construct an explicit four-dimensional UV completion and discuss a variety of UV completions relevant for both vector-like and fraternal twin Higgs models.

  1. There are two twin shadows, but einstein is one

    Directory of Open Access Journals (Sweden)

    Popović Marko E.

    2012-01-01

    Full Text Available 2011 is the international year of chemistry, and it is exactly 100 years past after the P. Langevin promotion of “twin paradox” problem. The hundred year old problem still demands its solution. Twin paradox, established by a physicist, has been representing a nightmare for philosophers, physicists, chemists, and biologists until these days. After a hundred years, it is time to try to close this page in long history of misunderstanding of the special relativity. This analysis has three main assumptions. First, biological systems are a part of physical world and therefore they behave in accordance to the physical laws according to Schrödinger. Second, according to Von Bertalanffy the biological systems are open thermodynamic systems. Because of that the approach of non-equilibrium thermodynamics was used for analyzing the twin paradox. Third, rise of entropy is according to Hyflick strongly connected with aging. Entropy can be taken as a measure of cell age or even human age according to Silva et al. and Gladyshev. So entropy invariance strongly suggests that both twins should be the same age, so there is a potential problem for twin paradox with the second law. The only possible influence of relativity on the chemical reaction rate is time dilatation. However time flow does not cause the aging process, so time dilatation cannot have any influence on it. So, after detailed analysis, it is concluded that there is no twin paradox in reality. Both twins will be exactly in same thermodynamic state and bio-logical age. The traveler twin will notice time dilatation, but this relativistic effect has no influence on the aging process.

  2. A Rare Case of Antepartum Spontaneous Septostomy in a Monochorionic Diamniotic Twin Pregnancy

    Directory of Open Access Journals (Sweden)

    Rati Chadha

    2012-01-01

    Full Text Available Spontaneous septostomy in a monochorionic diamniotic twin pregnancy is a rare phenomenon. We present a case of monochorionic diamniotic twin pregnancy with an intact dividing membrane seen in the 1st half of the pregnancy. At 26 weeks, when she was assessed for preterm contractions, the dividing membrane was not documented, which suggested spontaneous septostomy. There had been no invasive procedures during the pregnancy. She subsequently delivered at 29 weeks, secondary to preterm labor. No dividing membrane was noticed at the time of caesarian section. Spontaneous septostomy can complicate the management of monochorionic diamniotic twins by creating a pseudomonoamniotic environment resulting in cord entanglement, and difficulty in the diagnosis and management of twin-twin transfusion syndrome. We believe that such a case should be managed as monochorionic monoamniotic twin gestation.

  3. Fivefold twinned boron carbide nanowires.

    Science.gov (United States)

    Fu, Xin; Jiang, Jun; Liu, Chao; Yuan, Jun

    2009-09-01

    Chemical composition and crystal structure of fivefold twinned boron carbide nanowires have been determined by electron energy-loss spectroscopy and electron diffraction. The fivefold cyclic twinning relationship is confirmed by systematic axial rotation electron diffraction. Detailed chemical analysis reveals a carbon-rich boron carbide phase. Such boron carbide nanowires are potentially interesting because of their intrinsic hardness and high temperature thermoelectric property. Together with other boron-rich compounds, they may form a set of multiply twinned nanowire systems where the misfit strain could be continuously tuned to influence their mechanical properties.

  4. Failure of vincristine induce twinning

    Science.gov (United States)

    Binder, M.

    1984-01-01

    Mammalian ova do not contain axes of symmetry from which are derived embryonic axes of symmetry. Mammalian axis determination is an early embryologic event occurring at about the time that monozygous twinning in mice. (Kaufma MH & O'Shea KS, 1978, Nature 276:707) and an attempt was made to reproduce their work in several strains of mice. Over 3200 embryos were examined without any twins being found. To rule out the possibility that vincristine caused twinning plus some lethal malformation (with subsequent resorption of the embryo) the embryos were examined 36-60 hours after vincristine treatment.

  5. Investigation of mass suicide of siblings taken place in Kahramanmaraş

    Directory of Open Access Journals (Sweden)

    Ramazan Karanfil

    2012-12-01

    Full Text Available Objectives: Suicide is a major public health problem andchallenging issue of forensic medicine, in our country asin all over the world. This study aimed to present medicolegalevaluation of group/mass suicide cases of siblings.Material and methods: A total of 535 cases, autopsiedin Kahramanmaraş between 01.01.2007 and 01.06.2012,were retrospectively investigated. There were two casesof group suicide of four siblings for each. The autopsyand forensic investigation records of these cases wereinvestigated.Results: There were two cases of group/mass suicide.Each of them comprised four siblings. In first case, thegroup comprised of 3 male and 1 female siblings. Sceneinvestigation did not reveal a suspicious finding. Interviewingwith the relatives showed that siblings were extremelydependent on their mother who was currentlydied, after which victims suffered social adjustment problems.Autopsy findings revealed that all victims died ofasphyxia due to hanging. In second case, four female siblingsfound dead in a damn lake, a short while after leavinghome. All found to wear similar black colored dresses.Interviewing family members revealed that the oldestsister was forced for an unwanted marriage. The familyhas a low socioeconomic level and migrated from anotherregion. Death was attributed to asphyxia due to drowning.Conclusions: In the etiology of suicide, psychologicaland environmental factors should be investigated. Implementingpsychosocial support mechanisms is of highimportance in order to avoid such consequences, particularlyfor broken families and in regions suffering fromunwanted forced marriages. J Clin Exp Invest 2012; 3(4:514-517Key words: Suicide, sibling, hanging, drowning, autopsy

  6. Mitochondrial genome sequences reveal deep divergences among Anopheles punctulatus sibling species in Papua New Guinea

    Directory of Open Access Journals (Sweden)

    Logue Kyle

    2013-02-01

    Full Text Available Abstract Background Members of the Anopheles punctulatus group (AP group are the primary vectors of human malaria in Papua New Guinea. The AP group includes 13 sibling species, most of them morphologically indistinguishable. Understanding why only certain species are able to transmit malaria requires a better comprehension of their evolutionary history. In particular, understanding relationships and divergence times among Anopheles species may enable assessing how malaria-related traits (e.g. blood feeding behaviours, vector competence have evolved. Methods DNA sequences of 14 mitochondrial (mt genomes from five AP sibling species and two species of the Anopheles dirus complex of Southeast Asia were sequenced. DNA sequences from all concatenated protein coding genes (10,770 bp were then analysed using a Bayesian approach to reconstruct phylogenetic relationships and date the divergence of the AP sibling species. Results Phylogenetic reconstruction using the concatenated DNA sequence of all mitochondrial protein coding genes indicates that the ancestors of the AP group arrived in Papua New Guinea 25 to 54 million years ago and rapidly diverged to form the current sibling species. Conclusion Through evaluation of newly described mt genome sequences, this study has revealed a divergence among members of the AP group in Papua New Guinea that would significantly predate the arrival of humans in this region, 50 thousand years ago. The divergence observed among the mtDNA sequences studied here may have resulted from reproductive isolation during historical changes in sea-level through glacial minima and maxima. This leads to a hypothesis that the AP sibling species have evolved independently for potentially thousands of generations. This suggests that the evolution of many phenotypes, such as insecticide resistance will arise independently in each of the AP sibling species studied here.

  7. Effect of triple junctions on deformation twinning in a nanostructured Cu–Zn alloy: A statistical study using transmission Kikuchi diffraction

    Directory of Open Access Journals (Sweden)

    Silu Liu

    2016-10-01

    Full Text Available Scanning electron microscopy transmission Kikuchi diffraction is able to identify twins in nanocrystalline material, regardless of their crystallographic orientation. In this study, it was employed to characterize deformation twins in Cu/10 wt % Zn processed by high-pressure torsion. It was found that in 83% of grains containing twins, at least one twin intersects with a triple junction. This suggests that triple junctions could have promoted the nucleation of deformation twins. It should be cautioned that this technique might be unable to detect extremely small nanoscale twins thinner than its step size.

  8. Sibling relationship quality and psychosocial outcomes among adult siblings of individuals with autism spectrum disorder and individuals with intellectual disability without autism.

    Science.gov (United States)

    Tomeny, Theodore S; Ellis, Brandi M; Rankin, James A; Barry, Tammy D

    2017-03-01

    Research on adult typically-developing (TD) siblings of individuals with developmental disabilities remains limited, and outcomes for TD siblings appear to vary widely. For the current study, 82 adult TD siblings of individuals with autism spectrum disorder (ASD) or intellectual disability (ID) completed questionnaires about themselves and their affected sibling. Results of this study suggest that the attitudes possessed by adult TD siblings are important to consider when understanding adult TD sibling outcomes. Specifically, data indicate that higher levels of positive sibling relationship attitudes are related to TD siblings providing more aid/support to their sibling with a disability, along with having higher levels of general life satisfaction, and negatively related to levels of stress and depressive symptoms among TD siblings. Consistent with previous child research, siblings of individuals with ASD reported fewer positive sibling relationship attitudes compared to siblings of individuals with ID. Finally, group membership related to aid provided, depressive symptoms, and stress of TD siblings indirectly through sibling relationship attitudes. Overall, results indicate that sibling relationship attitudes may be particularly important to consider when conceptualizing sibling relationships when one sibling has an intellectual or developmental disability.

  9. Cognitive functions in neurofibromatosis type 1 patients and unaffected siblings.

    Science.gov (United States)

    Erdoğan-Bakar, Emel; Cinbiş, Mine; Ozyürek, Hamit; Kiriş, Nurcihan; Altunbaşak, Sakir; Anlar, Banu

    2009-01-01

    Attention, learning, and perceptual problems have been reported at various degrees and rates in neurofibromatosis type 1 (NF1). We aimed to define the cognitive profiles frequently associated with NF1. Children and adolescents with NF1 (n=58) were tested using Wechsler Intelligence Scales for Children-Revised (WISC-R), Judgment of Line Orientation, and Bender Visual-Motor Gestalt tests. Comparison groups were unaffected siblings of NF1 patients (n=20), children with attention deficit and hyperactivity disorder (ADHD, n=40), and normal children (n=40). No difference was found between familial or sporadic NF1 cases. Seventeen/58 (29%) of NF1 cases had a full scale IQ80 (n=27) scored lower in WISC-R subtests measuring visual perception when compared to a healthy control group of similar intelligence, and lower in arithmetic but better in Bender-Gestalt and Judgment of Line Orientation tests when compared to an ADHD group of similar intelligence. These results indicate a high prevalence of mental retardation in a clinical NF1 series. NF1 patients who have normal intelligence may have impaired visual perception, but their visual perceptual problems are less than in ADHD. The tendency of unaffected siblings of NF1 patients to have mildly but consistently low test scores compared to healthy controls needs to be studied further for underlying genetic or environmental factors.

  10. Number of siblings, birth order, and childhood overweight: a population-based cross-sectional study in Japan

    Directory of Open Access Journals (Sweden)

    Ochiai Hirotaka

    2012-09-01

    Full Text Available Abstract Background Although several studies have investigated the relationship between the number of siblings or birth order and childhood overweight, the results are inconsistent. In addition, little is known about the impact of having older or younger siblings on overweight among elementary schoolchildren. The present population-based study investigated the relationship of the number of siblings and birth order with childhood overweight and evaluated the impact of having younger or older siblings on childhood overweight among elementary schoolchildren in Japan. Methods Subjects comprised fourth-grade schoolchildren (age, 9–10 years in Ina Town during 1999–2009. Information about subjects’ sex, age, birth weight, birth order, number of siblings, lifestyle, and parents’ age, height, and weight was collected by a self-administered questionnaire, while measurements of subjects’ height and weight were done at school. Childhood overweight was defined according to age- and sex-specific cut-off points proposed by the International Obesity Task Force. A logistic regression model was used to calculate the odds ratio (OR and 95% confidence intervals (95% CI of "number of siblings" or "birth order" for overweight. Results Data from 4026 children were analyzed. Only children (OR: 2.13, 95% CI: 1.45-3.14 and youngest children (1.56, 1.13-2.16 significantly increased ORs for overweight compared with middle children. A larger number of siblings decreased the OR for overweight (P for trend P for trend  Conclusions Being an only or youngest child was associated with childhood overweight, and having a larger number of younger siblings was negatively associated with overweight. The present study suggests that public health interventions to prevent childhood overweight need to focus on children from these family backgrounds.

  11. Correlation between diabetes autoantibodies and environmental parameters in type 1 diabetics and their siblings in Abidjan District, Ivory Coast

    Directory of Open Access Journals (Sweden)

    Trébissou AFJ

    2017-01-01

    Full Text Available Objective: The aim of this work is to determine the correlation between the presence of diabetes autoantibodies and certain environmental parameters and diet in type 1 diabetes (T1D and their siblings. Methods: The study population consisted of 49 people, including 19 with T1D and 30 siblings of first degree whose blood and faeces were collected. T1D were recruited from two University hospital centres in Cote d’Ivoire. Serum obtained allowed the determination of anti-ICA autoantibodies by the immunofluorescence method, anti-GAD and anti-IA2 detected by ELISA. Blood parasites were sought by the drop of thick and blood smears. Intestinal parasites were searched by the direct method, Kato and Ritchie techniques. Yeasts isolation was done on Sabouraud chloranphénicol and identifying by the chromatic Candida medium. Pinworms were sought by the anal scotch test technique. Vaccines and food were mentioned on a survey sheet. Results: The 3 diabetes autoantibodies were present in T1D and 2 combinations anti-GAD-IA2 among siblings (p<0.0001. Hand pinworms, DT1 and their siblings infected with blood parasites are respectively, intestinal parasites, yeast. The diet of T1D significantly different from that of siblings (p=0.031<0.05. Conclusion: There is no correlation between the presence of diabetes autoantibodies and blood and intestinal parasites, yeasts, pinworms among siblings of diabetics. Their diet should be balanced to avoid the installation of diabetes.

  12. Elevated homocysteine level in siblings of patients with schizophrenia.

    Science.gov (United States)

    Geller, Vadim; Friger, Michael; Sela, Ben-Ami; Levine, Joseph

    2013-12-30

    Increased homocysteine plasma levels were reported in patients with schizophrenia and Levine et al. (2002) suggested that such increase characterizes mainly males. In the following study we examined whether such increased levels also characterize male siblings of schizophrenia patients. Forty-four pairs of schizophrenia patients and their corresponding healthy male siblings were recruited and sampled for homocysteine. We also had age-matched controls for each of the sibling. The median homocysteine plasma level for patients was 13.0 µMol/L and 11.7 µMol/L for their male siblings compared with a median of 10.9 µMol/L for the siblings' controls. There was no significant difference between homocysteine plasma level in patients and their siblings. Significant difference was found for homocysteine plasma level between the siblings' group and their matched controls. A partial correlation of Ln plasma homocysteine level between patients and their siblings was found to be close to a zero correlation of -0.089, p=0.57 for the whole study group and -0.15, p=0.38 in the male-male patient-sibling pairs. Our results show that elevated homocysteine plasma level may characterize schizophrenia patients' male siblings, a finding that seems to agree with previous studies suggesting elevated homocysteine level as a risk factor for developing schizophrenia.

  13. Structural Join and Staircase Join Algorithms of Sibling Relationship

    Institute of Scientific and Technical Information of China (English)

    Chang-Xuan Wan; Xi-Ping Liu

    2007-01-01

    The processing of XML queries can result in evaluation of various structural relationships. Efficient algorithms for evaluating ancestor-descendant and parent-child relationships have been proposed. Whereas the problems of evaluating preceding-sibling-following-sibling and preceding-following relationships are still open. In this paper, we studied the struc-tural join and staircase join for sibling relationship. First, the idea of how to filter out and minimize unnecessary reads of elements using parent's structural information is introduced, which can be used to accelerate structural joins of parent-child and preceding-sibling-following-sibling relationships. Second, two efficient structural join algorithms of sibling relationship are proposed. These algorithms lead to optimal join performance: nodes that do not participate in the join can be judged beforehand and then skipped using B+-tree index. Besides, each element list joined is scanned sequentially once at most.Furthermore, output of join results is sorted in document order. We also discussed the staircase join algorithm for sibling axes. Studies show that, staircase join for sibling axes is close to the structural join for sibling axes and shares the samecharacteristic of high efficiency. Our experimental results not only demonstrate the effectiveness of our optimizing techniquesfor sibling axes, but also validate the efficiency of our algorithms. As far as we know, this is the first work addressing thisproblem specially.

  14. Genetic and Environmental Influences on Symptom Domains in Twins and Siblings with Autism

    Science.gov (United States)

    Mazefsky, Carla A.; Goin-Kochel, Robin P.; Riley, Brien P.; Maes, Hermine H.

    2008-01-01

    Clarifying the sources of variation among autism symptom domains is important to the identification of homogenous subgroups for molecular genetic studies. This study explored the genetic and environmental bases of nonverbal communication and social interaction, two symptom domains that have also been related to treatment response, in 1294 child…

  15. Genetic and Environmental Influences on Symptom Domains in Twins and Siblings with Autism

    Science.gov (United States)

    Mazefsky, Carla A.; Goin-Kochel, Robin P.; Riley, Brien P.; Maes, Hermine H.

    2008-01-01

    Clarifying the sources of variation among autism symptom domains is important to the identification of homogenous subgroups for molecular genetic studies. This study explored the genetic and environmental bases of nonverbal communication and social interaction, two symptom domains that have also been related to treatment response, in 1294 child…

  16. CLINICAL STUDY OF LABOUR IN TWIN PREGNANCY

    Directory of Open Access Journals (Sweden)

    Amudha

    2015-07-01

    Full Text Available OBJECTIVES: The objective of the present study is to analyse the incidence of preterm labour, intrapartum complications, incidence of operative delivery both vaginal and cesarean and indications for such interventions. METHODOLOGY: A total of 150 cases of twin pregnancy were analyzed between the period of September 2012 to February 2014. These cases were stud ied with respect to period of gestation at the onset of labour, fetal presentations at the onset of labour, route and mode of delivery, indications in cases of cesarean delivery, intrapartum complications and delivery interval between twins. OBSERVATIONS A ND RESULTS: In the present study there was increased incidence of preterm labour (52.6%, fetal malpresentations (43.3%, operative vaginal delivery (29.5%, cesarean delivery (17.3%. CONCLUSION: In this study it is observed that above mentioned labour ev ents and complications double up in the event of a twin pregnancy. Regular antenatal visits, planned delivery and anticipation and identification of complications will help for better pregnancy outcome.

  17. Twin-to-twin transfusion syndrome : from placental anastomoses to long-term outcome

    NARCIS (Netherlands)

    Lopriore, Enrico

    2006-01-01

    Twin-to-twin transfusion syndrome (TTTS) is a severe complication of monochorionic twin pregnancies associated with high perinatal mortality and morbidity rates. Placental vascular anastomoses, almost invariably present in monochorionic placentas, are the essential anatomical substrate for the devel

  18. Twin-to-twin transfusion syndrome : from placental anastomoses to long-term outcome

    NARCIS (Netherlands)

    Lopriore, Enrico

    2006-01-01

    Twin-to-twin transfusion syndrome (TTTS) is a severe complication of monochorionic twin pregnancies associated with high perinatal mortality and morbidity rates. Placental vascular anastomoses, almost invariably present in monochorionic placentas, are the essential anatomical substrate for the

  19. Twin-to-twin transfusion syndrome : from placental anastomoses to long-term outcome

    NARCIS (Netherlands)

    Lopriore, Enrico

    2006-01-01

    Twin-to-twin transfusion syndrome (TTTS) is a severe complication of monochorionic twin pregnancies associated with high perinatal mortality and morbidity rates. Placental vascular anastomoses, almost invariably present in monochorionic placentas, are the essential anatomical substrate for the devel

  20. Multivariate genetic analysis of brain structure in an extended twin design

    DEFF Research Database (Denmark)

    Posthuma, D; de Geus, E.J.; Neale, M.C.;

    2000-01-01

    . The analysis is carried out on the raw data and specifies a model for the mean and the covariance structure. Results suggest that cerebellar volume and intracranial space vary with age and sex. Brain volumes tend to decrease slightly with age, and males generally have a larger brain volume than females....... Intermediate phenotypes for discrete traits, such as psychiatric disorders, can be neurotransmitter levels, brain function, or structure. In this paper we conduct a multivariate analysis of data from 111 twin pairs and 34 additional siblings on cerebellar volume, intracranial space, and body height...

  1. Should selecting saviour siblings be banned?

    OpenAIRE

    Sheldon, Sally; Wilkinson, Stephen

    2004-01-01

    By using tissue typing in conjunction with preimplantation genetic diagnosis doctors are able to pick a human embryo for implantation which, if all goes well, will become a "saviour sibling", a brother or sister capable of donating life-saving tissue to an existing child. \\ud \\ud This paper addresses the question of whether this form of selection should be banned and concludes that it should not. Three main prohibitionist arguments are considered and found wanting: (a) the claim that saviour ...

  2. Prognostic and survival analysis of presbyopia: The healthy twin study

    Science.gov (United States)

    Lira, Adiyani; Sung, Joohon

    2015-12-01

    Presbyopia, a vision condition in which the eye loses its flexibility to focus on near objects, is part of ageing process which mostly perceptible in the early or mid 40s. It is well known that age is its major risk factor, while sex, alcohol, poor nutrition, ocular and systemic diseases are known as common risk factors. However, many other variables might influence the prognosis. Therefore in this paper we developed a prognostic model to estimate survival from presbyopia. 1645 participants which part of the Healthy Twin Study, a prospective cohort study that has recruited Korean adult twins and their family members based on a nation-wide registry at public health agencies since 2005, were collected and analyzed by univariate analysis as well as Cox proportional hazard model to reveal the prognostic factors for presbyopia while survival curves were calculated by Kaplan-Meier method. Besides age, sex, diabetes, and myopia; the proposed model shows that education level (especially engineering program) also contribute to the occurrence of presbyopia as well. Generally, at 47 years old, the chance of getting presbyopia becomes higher with the survival probability is less than 50%. Furthermore, our study shows that by stratifying the survival curve, MZ has shorter survival with average onset time about 45.8 compare to DZ and siblings with 47.5 years old. By providing factors that have more effects and mainly associate with presbyopia, we expect that we could help to design an intervention to control or delay its onset time.

  3. Discordant Epilepsy in Monozygous Twins

    OpenAIRE

    2001-01-01

    Twelve monozygotic twins, discordant for epilepsy, were analysed for nonhereditary etiological factors by clinical history, MRI, and quantitative brain volume studies at the Brain Research Institute, University of Melbourne, Victoria, Australia.

  4. Sibling relationship quality and Mexican-origin adolescents' and young adults' familism values and adjustment.

    Science.gov (United States)

    Killoren, Sarah E; De Jesús, Sue A Rodríguez; Updegraff, Kimberly A; Wheeler, Lorey A

    2017-03-01

    We examined profiles of sibling relationship qualities in 246 Mexican-origin families living in the United States using latent profile analyses. Three profiles were identified: Positive, Negative and Affect-Intense. Links between profiles and youths' familism values and adjustment were assessed using longitudinal data. Siblings in the Positive profile reported the highest familism values, followed by siblings in the Affect-Intense profile and, finally, siblings in the Negative profile. Older siblings in the Positive and Affect-Intense profiles reported fewer depressive symptoms than siblings in the Negative profile. Further, in the Positive and Negative profiles, older siblings reported less involvement in risky behaviors than younger siblings. In the Negative profile, younger siblings reported greater sexual risk behaviors in late adolescence than older siblings; siblings in opposite-sex dyads, as compared to same-sex dyads, engaged in riskier sexual behaviors. Our findings highlight sibling relationship quality as promotive and risky, depending on sibling characteristics and adjustment outcomes.

  5. Hypertensive disorders in twin pregnancy

    OpenAIRE

    Santema, Job; Koppelaar, Elin; Wallenburg, Henk

    1995-01-01

    textabstractObjective: To compare the incidence and severity of pregnancy-induced hypertensive disorders in twin pregnancy and in singleton gestation. Study design: Case-control study in the setting of a University Hospital. Each pregnancy of a consecutive series of 187 twin pregnancies attending the antenatal clinic and booked before a gestational age of 24 weeks was matched for maternal age, parity, and gestational age at delivery with a singleton pregnancy delivered in the same year. Prima...

  6. Adult Female and Male Siblings of Persons with Disabilities: Findings from a National Survey

    Science.gov (United States)

    Hodapp, Robert M.; Urbano, Richard C.; Burke, Meghan M.

    2010-01-01

    In this study, the authors used a national, Web-based survey to examine female and male siblings of individuals with disabilities. More than 1,160 adult siblings completed a 163-question survey about themselves, their siblings, and their sibling relationships. Most respondents reported fairly close contact with their siblings and positive sibling…

  7. The Impact of Sibling Warmth and Conflict on Children's Social Competence with Peers.

    Science.gov (United States)

    Lockwood, Rebecca L.; Kitzmann, Katherine M.; Cohen, Robert

    2001-01-01

    Examined links between children's sibling and peer relationships. Found that sibling warmth was associated with more positive peer relations; sibling conflict was associated with both positive and negative peer outcomes, independent of sibling warmth; and sibling relationships were not more strongly associated with measures of friendships quality…

  8. Brief report: Physical health of adolescent perpetrators of sibling aggression.

    Science.gov (United States)

    Tucker, Corinna Jenkins; Van Gundy, Karen; Sharp, Erin Hiley; Rebellon, Cesar

    2015-12-01

    We describe adolescents' perpetration of sibling aggression and its link to physical health two years later. In-school surveys at Time 1 (N = 331) and Time 2 (two-years later, N = 283) were administered to adolescents (at Time 1, Mage = 15.71 years, SD = .63; 52% female) living in the United States querying about perpetration of aggression toward a sibling closest in age and perceived physical health. The majority of adolescents perpetrated aggression towards their sibling (74%). Adolescents who were part of brother-brother pairs reported the most aggression. Hierarchical regression analysis showed that perpetrating sibling aggression more often at Time 1 was predictive of lower physical health at Time 2 controlling for Time 1 physical health and demographic characteristics. Perpetration of aggression toward a sibling is common and has negative health consequences in late adolescence suggesting this issue should be targeted to improve adolescents' sibling dynamics and physical health.

  9. Quest for finding the lost siblings of the Sun

    CERN Document Server

    Liu, C; Feltzing, S; Martínez-Barbosa, C A; Bensby, T; Brown, A G A; Zwart, S F Portegies

    2014-01-01

    The aim of this paper is to find lost siblings of the Sun by analyzing high resolution spectra. Finding solar siblings will enable us to constrain the parameters of the parental cluster and the birth place of the Sun in the Galaxy. The solar siblings can be identified by accurate measurements of metallicity, stellar age and elemental abundances for solar neighbourhood stars. The solar siblings candidates were kinematically selected based on their proper motions, parallaxes and colours. Stellar parameters were determined through a purely spectroscopic approach and partly physical method, respectively. Comparing synthetic with observed spectra, elemental abundances were computed based on the stellar parameters obtained using a partly physical method. A chemical tagging technique was used to identify the solar siblings. We present stellar parameters, stellar ages, and detailed elemental abundances for Na, Mg, Al, Si, Ca, Ti, Cr, Fe, and Ni for 32 solar sibling candidates. Our abundances analysis shows that four ...

  10. Spondyloepiphyseal Dysplasia Tarda in Twins

    Directory of Open Access Journals (Sweden)

    Ferhat Çekmez

    2011-08-01

    Full Text Available Introduction: Spondyloepiphyseal dysplasia (SED is a genetically heterogeneous disorder often associated with the early onset of osteoarthrosis. The X-linked recessive form (SEDL affects boys and is characterized by reduced height, arm span exceeding total height, and barrel chest deformity. The radiographic phenotype comprises a hump-shaped deformity of vertebral bodies and mild epiphyseal dysplasia of the femoral head associated with early signs of hip arthrosis.The disorder is caused by mutations in the SEDL (or sedlin gene on Xp22.12-p22.31. SED should be kept in mind as a differential diagnosis in men with early “primary” bilateral osteoarthrosis.Case Report: Here, 11 years old twins diagnosed as SED due to walking disability, limitation of joint motion, pain at the hips and disability in standing for a long time were presented. Discussion: This rare skelatal dysplasia must be kept in mind in patients with painful spine and hip joints, and walking disability. (Jo­ur­nal of Cur­rent Pe­di­at­rics 2011; 9: 97-9

  11. The Qingdao Twin Registry: a status update.

    Science.gov (United States)

    Duan, Haiping; Ning, Feng; Zhang, Dongfeng; Wang, Shaojie; Zhang, Dong; Tan, Qihua; Tian, Xiaocao; Pang, Zengchang

    2013-02-01

    In 1998, the Qingdao Twin Registry was initiated as the main part of the Chinese National Twin Registry. By 2005, a total of 10,655 twin pairs had been recruited. Since then new twin cohorts have been sampled, with one longitudinal cohort of adolescent twins selected to explore determinants of metabolic disorders and health behaviors during puberty and young adulthood. Adult twins have been sampled for studying heritability of multiple phenotypes associated with metabolic disorders. In addition, an elderly twin cohort has been recruited with a focus on genetic studies of aging-related phenotypes using twin modeling and genome-wide association analysis. Cross-cultural collaborative studies have been carried out between China, Denmark, Finland, and US cohorts. Ongoing data collection and analysis for the Qingdao Twin Registry will be discussed in this article.

  12. Twin Town in South Brazil: a Nazi's experiment or a genetic founder effect?

    Directory of Open Access Journals (Sweden)

    Alice Tagliani-Ribeiro

    Full Text Available Cândido Godói (CG is a small municipality in South Brazil with approximately 6,000 inhabitants. It is known as the "Twins' Town" due to its high rate of twin births. Recently it was claimed that such high frequency of twinning would be connected to experiments performed by the German Nazi doctor Joseph Mengele. It is known, however, that this town was founded by a small number of families and therefore a genetic founder effect may represent an alternatively explanation for the high twinning prevalence in CG. In this study, we tested specific predictions of the "Nazi's experiment" and of the "founder effect" hypotheses. We surveyed a total of 6,262 baptism records from 1959-2008 in CG catholic churches, and identified 91 twin pairs and one triplet. Contrary to the "Nazi's experiment hypothesis", there is no spurt in twinning between the years (1964-1968 when Mengele allegedly was in CG (P = 0.482. Moreover, there is no temporal trend for a declining rate of twinning since the 1960s (P = 0.351, and no difference in twinning among CG districts considering two different periods: 1927-1958 and 1959-2008 (P = 0.638. On the other hand, the "founder effect hypothesis" is supported by an isonymy analysis that shows that women who gave birth to twins have a higher inbreeding coefficient when compared to women who never had twins (0.0148, 0.0081, respectively, P = 0.019. In summary, our results show no evidence for the "Nazi's experiment hypothesis" and strongly suggest that the "founder effect hypothesis" is a much more likely alternative for explaining the high prevalence of twinning in CG. If this hypothesis is correct, then this community represents a valuable population where genetic factors linked to twinning may be identified.

  13. Adolescents' Social Skills in Friendship : The influence of sibling relationship

    OpenAIRE

    藤田, 文; Aya, FUJITA

    1998-01-01

    The purpose of this study was to investigate the influence of the sibling relationship on the adolescents' social skills in friendship. One hundred and seventy-seven undergraduate students were asked to complete a questionnaire regarding their sibling relationship and their social skills in friendship. Their sibling relationship was categorized eight types; close, intimate, hostile, dominate, intimate-hostile, intimate-dominate, hostile-dominate, separate. The result showed that the students ...

  14. Chromosome 22q11.2 microdeletion in monozygotic twins with discordant phenotype and deletion size

    Directory of Open Access Journals (Sweden)

    Halder Ashutosh

    2012-03-01

    Full Text Available Abstract We report on a pair of male monozygotic twins with 22q11.2 microdeletion, discordant phenotype and discordant deletion size. The second twin had findings suggestive of DiGeorge syndrome, while the first twin had milder anomalies without any cardiac malformation. The second twin had presented with intractable convulsion, cyanosis and cardiovascular failure in the fourth week of life and expired on the sixth week of life, whereas the first twin had some characteristic facial appearance with developmental delay but no other signs of the 22q11.2 microdeletion syndrome including cardiovascular malformation. The fluorescence in situ hybridization (FISH analysis had shown a microdeletion on the chromosome 22q11.2 in both twins. The interphase FISH did not find any evidence for the mosaicism. The genomic DNA microarray analysis, using HumanCytoSNP-12 BeadChip (Illumina, was identical between the twins except different size of deletion of 22q11.2. The zygosity using HumanCytoSNP-12 BeadChip (Illumina microarray analysis suggested monozygosity. This observation indicates that altered size of the deletion may be the underlying etiology for the discordance in phenotype in monozygotic twins. We think early post zygotic events (mitotic non-allelic homologous recombination could have been played a role in the alteration of 22q11.2 deletion size and, thus phenotypic variability in the monozygotic twins.

  15. Impact of childhood chronic illnesses on siblings: a literature review.

    LENUS (Irish Health Repository)

    O' Brien, Irene

    2012-02-01

    BACKGROUND: Childhood illness can have a significant impact on families, particularly on the ill child\\'s siblings. There is a dearth of published literature focusing on the needs of siblings of ill children. AIM: This literature review aims to provide an overview of the current healthcare literature in relation to the impact of childhood chronic illness or disability on siblings. METHOD: A literature review was undertaken by searching the databases CINAHL, PsycINFO, ProQuest and Cochrane Library for relevant articles in English using the search terms: \\'siblings\\

  16. Hydrodynamic optimization of twin-skeg LNG ships by CFD and model testing

    Directory of Open Access Journals (Sweden)

    Keunjae Kim

    2014-06-01

    Full Text Available SSPA experiences a growing interest in twin skeg ships as one attractive green ship solution. The twin skeg concept is well proven with obvious advantages for the design of ships with full hull forms, restricted draft or highly loaded propellers. SSPA has conducted extensive hull optimizations studies of LNG ships of different size based on an extensive hull data base with over 7,000 models tested, including over 400 twin skeg hull forms. Main hull dimensions and different hull concepts such as twin skeg and single screw were of main interest in the studies. In the present paper, one twin skeg and one single screw 170 K LNG ship were designed for optimally selected main dimension parameters. The twin skeg hull was further optimized and evaluated using SHIPFLOW FRIENDSHIP design package by performing parameter variation in order to modify the shape and positions of the skegs. The finally optimized models were then built and tested in order to confirm the lower power demand of twin skeg designed compaed with the signle screw design. This paper is a full description of one of the design developments of a LNG twin skeg hull, from early dimensional parameter study, through design optimization phase towards the confirmation by model tests.

  17. Surprising dissimilarities in a newly formed pair of 'identical twin' stars.

    Science.gov (United States)

    Stassun, Keivan G; Mathieu, Robert D; Cargile, Phillip A; Aarnio, Alicia N; Stempels, Eric; Geller, Aaron

    2008-06-19

    The mass and chemical composition of a star are the primary determinants of its basic physical properties-radius, temperature and luminosity-and how those properties evolve with time. Accordingly, two stars born at the same time, from the same natal material and with the same mass, are 'identical twins,' and as such might be expected to possess identical physical attributes. We have discovered in the Orion nebula a pair of stellar twins in a newborn binary star system. Each star in the binary has a mass of 0.41 +/- 0.01 solar masses, identical to within 2 per cent. Here we report that these twin stars have surface temperatures differing by approximately 300 K ( approximately 10 per cent) and luminosities differing by approximately 50 per cent, both at high confidence level. Preliminary results indicate that the stars' radii also differ, by 5-10 per cent. These surprising dissimilarities suggest that one of the twins may have been delayed by several hundred thousand years in its formation relative to its sibling. Such a delay could only have been detected in a very young, definitively equal-mass binary system. Our findings reveal cosmic limits on the age synchronization of young binary stars, often used as tests for the age calibrations of star-formation models.

  18. Measuring adolescents’ exposure to victimization: The Environmental Risk (E-Risk) Longitudinal Twin Study

    Science.gov (United States)

    Fisher, Helen L.; Caspi, Avshalom; Moffitt, Terrie E.; Wertz, Jasmin; Gray, Rebecca; Newbury, Joanne; Ambler, Antony; Zavos, Helena; Danese, Andrea; Mill, Jonathan; Odgers, Candice L.; Pariante, Carmine; Wong, Chloe C.; Arseneault, Louise

    2016-01-01

    This paper presents mutlilevel findings on adolescents’ victimization exposure from a large longitudinal cohort of twins. Data were obtained from the Environmental Risk (E-Risk) Longitudinal Twin Study, an epidemiological study of 2,232 children (1,116 twin pairs) followed to 18 years of age (with 93% retention). To assess adolescent victimization we combined best practices in survey research on victimization with optimal approaches to measuring life stress and traumatic experiences, and introduce a reliable system for coding severe victimization. One in three children experienced at least one type of severe victimization during adolescence (crime victimization, peer/sibling victimization, internet/mobile phone victimization, sexual victimization, family violence, maltreatment, or neglect), and most types of victimization were more prevalent amongst children from low socioeconomic backgrounds. Exposure to multiple victimization types was common, as was re-victimization; over half of those physically maltreated in childhood were also exposed to severe physical violence in adolescence. Biometric twin analyses revealed that environmental factors had the greatest influence on most types of victimization, while severe physical maltreatment from caregivers during adolescence was predominantly influenced by heritable factors. The findings from this study showcase how distinct levels of victimization measurement can be harmonized in large-scale studies of health and development. PMID:26535933

  19. Estimating twin concordance for bivariate competing risks twin data.

    Science.gov (United States)

    Scheike, Thomas H; Holst, Klaus K; Hjelmborg, Jacob B

    2014-03-30

    For twin time-to-event data, we consider different concordance probabilities, such as the casewise concordance that are routinely computed as a measure of the lifetime dependence/correlation for specific diseases. The concordance probability here is the probability that both twins have experienced the event of interest. Under the assumption that both twins are censored at the same time, we show how to estimate this probability in the presence of right censoring, and as a consequence, we can then estimate the casewise twin concordance. In addition, we can model the magnitude of within pair dependence over time, and covariates may be further influential on the marginal risk and dependence structure. We establish the estimators large sample properties and suggest various tests, for example, for inferring familial influence. The method is demonstrated and motivated by specific twin data on cancer events with the competing risk death. We thus aim to quantify the degree of dependence through the casewise concordance function and show a significant genetic component.

  20. Spina bifida occulta and monozygotic twins.

    Science.gov (United States)

    Spacca, Barbara; Buxton, Neil

    2008-10-01

    Central nervous system maldevelopment can have different presentations in twins. We report on a case of different presentations of spina bifida occulta in monozygotic twins. The first twin presented at birth with a lipomyelomeningocele; a tethered cord was diagnosed in the second twin at 2 years of age. Neural tube defects (NTDs) are a group of common congenital malformations of the brain and spine generated during neurulation. The genetic basis of this process is still not well known. Whenever an NTD is diagnosed in one of a pair of twins, the other twin should also be evaluated for NTDs.

  1. [The Chinese national twin cohort: an update].

    Science.gov (United States)

    Gao, W J; Li, L M

    2017-06-10

    The importance of large cohort studies in China has been increasingly emphasized. As special group in the population, twins provide excellent natural resources since they share the same birthday, maternal intrauterine environment and early family environment. Twin cohorts are unique for and benefit on controlling the confounding factors as age, gender (same-sex twins), genetic background (monozygotic twins) or early environment (being raised together) in the etiological studies on complex diseases. In this review, we briefly introduce the objectives, current situation, challenges and opportunities related to the Chinese national twin cohort, focusing on the characteristics of twins that are different from other groups in the general population.

  2. Inherited multicentric osteolysis: case report of three siblings treated with bisphosphonate

    Directory of Open Access Journals (Sweden)

    Whitewood Colin

    2010-04-01

    Full Text Available Abstract Inherited Multicentric Osteolysis (IMO is an uncommon familial condition of idiopathic pathophysiology causing bone osteolysis and dysplasia. These patients present with common rheumatologic complaints of pain, dysfunction and disability, and are often initially misdiagnosed as a chronic rheumatic disease of childhood such as juvenile idiopathic arthritis. We report a case of three siblings diagnosed with IMO. Diagnosis was made during childhood, with each sibling having different manifestations and course of disease. One had a previous history of bilateral hip dysplasia. Two had osteolysis of the foot, distal tibia and femur (lower limb bones, whilst one had osteolysis of the rib and unusual clavicular fractures. Unusually, all siblings appear to experience decreased pain sensation compared to norms. All siblings were treated with bisphosphonates and experienced a rapid improvement in pain symptoms, decreased analgesic requirements. Two had bone mineral density testing performed and both had increases post-bisphosphonate. In all three, there was subjective evidence of stabilisation of bone disease. Testing for matrix metalloproteinase-2 (MMP2 gene was negative.

  3. Penguin chicks benefit from elevated yolk androgen levels under sibling competition.

    Directory of Open Access Journals (Sweden)

    Maud Poisbleau

    Full Text Available Crested penguins (genus Eudyptes have a peculiar hatching pattern, with the first-laid egg (A-egg hatching after the second-laid egg (B-egg and chicks from A-eggs typically having a much lower survival probability. Maternal yolk androgens have been suggested to contribute to the competitive superiority of the B-chick in southern rockhopper penguins Eudyptes chrysocome, given their important role in mediating sibling competition in other species. We therefore increased the yolk androgen levels in freshly-laid eggs and examined the consequences for sibling competition--via effects on embryonic developmental times, chick growth and early survival. We placed one androgen-treated egg and one control egg into each foster nest, matching them for mass, laying date and laying order. The androgen treatment did not significantly affect embryonic developmental times or chick measurements at hatching. However, elevated yolk androgen levels benefitted chick growth in interaction with the number of siblings in a brood. Chicks from androgen-treated eggs had faster growth in the presence of a sibling than chicks from control eggs. Under these circumstances they also had a higher survival probability. Thus maternal androgens appear to reinforce the observed hatching pattern, facilitating brood reduction. This contrasts to most previous studies in other species where yolk androgens have been shown to compensate for the negative consequences of delayed hatching within the brood hierarchy.

  4. High speed twin roll caste for aluminum alloy thin strip

    Directory of Open Access Journals (Sweden)

    T. Haga

    2007-09-01

    Full Text Available Purpose: In the present study, effectiveness of a high-speed twin roll caster for recycling aluminum alloy was investigated.Design/methodology/approach: The effects of the high-speed twin roll caster on alleviating the deterioration of mechanical properties by impurities were investigated. Properties of the cast strip were investigated by metalography, a tension test, and a bending test.Findings: A vertical type twin roll caster for strip casting of aluminum alloys was devised. The strip, which was thinner than 3 mm, could be cast at speeds higher than 60 m/min. Features of the twin roll casters are as below. Copper rolls were used and lubricant was not used in order to increase the casting speed. A casting nozzle was used to set the solidification length precisely. Heat transfer between melt and the roll was improved by hydrostatic pressure of the melt. Separating force was very small in order to prevent sticking of the strip to the roll. Low superheat casting was carried out in order to improve microstructure of the strip. In the present study, effectiveness of a high-speed and high-cooling rate twin roll caster of the present study for recycling aluminum alloy was investigated. Fe was added as impurity to 6063 and A356. The roll caster of the present study was useful to decrease the influence of impurity of Fe.Research limitations/implications: A high-speed twin roll caster of vertical type was designed and assembled to cast aluminum alloy thin strip.Originality/value: The results demonstrate that the high-speed twin roll caster can improve the deterioration by impurities.

  5. Five Years of Stereo Magnetospheric Imaging by TWINS

    Science.gov (United States)

    Goldstein, J.; McComas, D. J.

    2013-12-01

    Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) is the first stereoscopic magnetospheric imager. TWINS is a NASA Explorer Mission of Opportunity performing simultaneous energetic neutral atom (ENA) imaging from two widely-separated Molniya orbits on two different spacecraft, and providing nearly continuous coverage of magnetospheric ENA emissions. The ENA imagers observe energetic neutrals produced from global ion populations, over a broad energy range (1-100 keV/u) with high angular (4∘×4∘) and time (about 1-minute) resolution. TWINS distinguishes hydrogen ENAs from oxygen ENAs. Each TWINS spacecraft also carries a Lyman- α geocoronal imager to monitor the cold exospheric hydrogen atoms that produce ENAs from ions via charge exchange. Complementing the imagers are detectors that measure the local charged particle environment around the spacecraft. During its first five years of science operations, TWINS has discovered new global properties of geospace plasmas and neutrals, fostered understanding of causal relationships, confirmed theories and predictions based on in situ data, and yielded key insights needed to improve geospace models. Analysis and modeling of TWINS data have: (1) obtained continuous (main phase through recovery) global ion spectra, (2) revealed a previously unknown local-time dependence of global pitch angle, (3) developed quantitative determination of ion fluxes from low altitude ENAs (4) determined dynamic connections between local pitch angle and global ion precipitation, (5) confirmed local-time dependence of precipitating ion temperature, (6) imaged global dynamic heating of the magnetosphere, (7) explained why the oxygen ring current survives longer into recovery than hydrogen, and (8) revealed new global exospheric density features and their influence upon ring current decay rates. Over the next several years of the solar cycle, TWINS observations of three-dimensional (3D) global ion dynamics, composition, origins and

  6. Quarreling Siblings or Friendly Neighbours?

    Directory of Open Access Journals (Sweden)

    Shantanu Chakrabarti

    2012-05-01

    Full Text Available El proceso de descolonización y la partición en el sur de Asia, dio lugar a discrepancias internas y la evolución de las dinámicas regionales a menudo competitivas y con propensión al conflicto. Esto ha sido particularmente cierto en el caso de la evolución de las relaciones bilaterales entre India y Pakistán desde 1947. Aunque los conflictos intermitentes, la tensión continua y la rivalidad han sido características principales de la relación bilateral, no ha existido una implacable hostilidad en ambos Estados. Han existido puntos brillantes de acercamiento, conectando a los dos países en distintos niveles de compromiso oficiales y no oficiales. La mejora de las relaciones ha llegado a ser esencial, ya que la dinámica regional ha llegado a convertirse en un juego de "suma cero" para uno u otro país en el período posterior de la Guerra Fría, dado que el "fracasado" o "radicalizado y "balcanizado" Pakistán no sólo pondría en peligro las perspectivas de paz y estabilidad en el sur de Asia, sino también se convertiría en un terrible problema global.

  7. Osteoporosis pseudoglioma syndrome. Update and report on two affected siblings

    Energy Technology Data Exchange (ETDEWEB)

    Swoboda, W.; Grill, F.

    1988-07-01

    Two siblings (male, 29 years, and female, 13 years) with the rare autosomal recessive osteoporosis pseudoglioma syndrome are reported in detail. All essential signs and symptoms of the full clinical picture were present and are documented by impressive X-ray pictures. Some aspects of our patients are compared with relevant findings of previous reports. Collagen studies (skin biopsies) failed to reveal any significant disorder of the main collagen types composition. Striking similarities with established genetic disorders of collagen (like the osteogenesis imperfecta group and the Ehlers-Danlos syndrome) suggest, however, that the OPS could be a primary collagen disorder. Genetic counselling and devoted socio-medical care for these handicapped children is presently the only help which can be offered.

  8. Agenesis of all third molars in two half siblings

    Directory of Open Access Journals (Sweden)

    Jamie A Kaufer

    2015-04-01

    Full Text Available Tooth agenesis is one of the most common dental anomalies and is influenced by factors including patient genetics. Although there are several specific genes associated with certain patterns of agenesis, there does not seem to be a genetic pattern identified to date that is associated with isolated complete third molar agenesis. This report presents two half-siblings who both express complete agenesis of third molars despite the fact that their shared parent does not express the same phenotype. The case discussion focuses on addressing the potential genetic possibilities including autosomal dominant inheritance and variable expressivity of a mutation.  There remains an uncertainty to the exact gene involved. Potential options include WNT10A and PAX9. The affected individuals are not needing extractions or experiencing complications due to the presence of third molars.  However, the concern remains that there is the potential for more severe expression of the mutation in future generations.

  9. Hypophosphatemic Rickets in Siblings: A Rare Case Report

    Directory of Open Access Journals (Sweden)

    Gummadapu Sarat

    2016-01-01

    Full Text Available Hypophosphatemic rickets (HR is a type of hereditary rickets characterized by persistent hypophosphatemia and hyperphosphaturia. The most predominant type is inherited in an X-linked fashion and caused by mutation in the gene encoding the phosphate-regulating endopeptidase homolog, X-linked (PHEX, identified in 1995. The X-linked hypophosphatemic (XLH rickets is a rare hereditary metabolic disorder with a prevalence of 1 in 20,000 and causes deficient calcification of mineralized structures such as bones and teeth resulting in dental problems in terms of delayed eruption, spontaneous periapical infections, and exfoliation. We report one such unique case of hypophosphatemic vitamin D-resistant rickets in siblings exhibiting classical features of rickets with emphasis on its treatment and dental considerations.

  10. Berardinelli-Seip congenital lipodystrophy in two siblings

    Directory of Open Access Journals (Sweden)

    T Rao

    2014-01-01

    Full Text Available Berardinelli-Seip congenital lipodystrophy (BSCL is a very rare autosomal recessive disorder characterized by various dermatological and systemic manifestations such as lipoatrophy, hypertriglyceridemia, hepatomegaly, acanthosis nigricans, and acromegaloid features. BSCL type 2 is more common and severe, with onset in the neonatal period or in early infancy. The locus for BSCL2 has been identified on chromosome 11q13. Early recognition and differentiation from other congenital generalized lipodystrophies help in the initiation of appropriate preventive and therapeutic measures such as lifestyle modification and pharmacotherapy that helps postpone the onset of metabolic syndrome. We report BSCL type 2 in two siblings with several cutaneous manifestations like acanthosis nigricans, hypertrichosis, prominent subcutaneous veins, and increased lanugo hair.

  11. Siblings of Youth with Autism Spectrum Disorders: Theoretical Perspectives on Sibling Relationships and Individual Adjustment

    Science.gov (United States)

    McHale, Susan M.; Updegraff, Kimberly A.; Feinberg, Mark E.

    2016-01-01

    A burgeoning research literature investigates the sibling relationships of youth with autism spectrum disorder (ASD) and their implications for individual adjustment. Focusing on four relationship domains--behaviors, emotions, cognitions and involvement--and toward advancing this generally atheoretical literature, we review and apply tenets from a…

  12. TwinMux Testing System

    CERN Document Server

    Wong, Wei Wen; CERN. Geneva. PH Department

    2015-01-01

    During the CERN summer school program, I joined the CMS Muon Drift Tube (DT) group, and mainly worked on two projects, which, both of them, are related to the electronics of a new data concentrator called the “TwinMux”. My first task within the TwinMux project was to build an integrated software test station in order to run several tests on the functionality of the TwinMux hardware. Essentially, I had to integrate existing testing scripts, adding several new ones, into a single user-friendly testing platform which can perform quick, convenient and automated hardware testing. Later, I was also involved in the design of the local technical triggering of the DT. Such system relies on some firmware functionality built in the TwinMux and controlled by software. I had attempted two different approaches to design the communication topology of all the 12 TwinMux cards in order to send a user-defined logical operation to the read-out electronics. The final goal of this system is to drive local trigger signal for...

  13. Two Stage Sibling Cycle Compressor/Expander.

    Science.gov (United States)

    1994-02-01

    vol. 5, p. 424. 11. L. Bauwens and M.P. Mitchell, " Regenerator Analysis: Validation of the MS*2 Stirling Cycle Code," Proc. XVIIIth International...PL-TR--94-1051 PL-TR-- 94-1051 TWO STAGE SIBLING CYCLE COMPRESSOR/EXPANDER Matthew P. Mitchell . Mitchell/ Stirling Machines/Systems, Inc. No\\ 1995...ty. THIS PAGE IS UNCLASSIFIED PL-TR-94-1051 This final report was prepared byMitchell/ Stirling Machines/Systems, Inc., Berkeley, CA under Contract

  14. Chronic mercury poisoning: Report of two siblings.

    Science.gov (United States)

    Yilmaz, Cahide; Okur, Mesut; Geylani, Hadi; Caksen, Hüseyin; Tuncer, Oğuz; Ataş, Bülent

    2010-01-01

    Mercury exists as organic inorganic and elementary forms in nature and is one of the most toxic metals that are poisonous for human beings. Mercury is commonly used in many different sectors of industry such as in insects formulas, agriculture products, lamps, batteries, paper, dyes, electrical/electronic devices, jewelry, and in dentistry. In this study, two siblings (one a 7-year-old boy and the other a 13 years old girl) are reported who developed chronic mercury poisoning as a result of long-term contact with batteries. Our aim is to emphasize the importance of mercury poisoning that is extremely rarely seen in childhood.

  15. Dyssegmental dysplasia in siblings: Prenatal ultrasonic diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, P.E. Jr.; Hauge, M.; Bang, J.

    1988-01-01

    Two cases of dyssegmental dysplasia (type Silverman-Handmaker) in siblings are presented. The first-born died at the age of 3 months and the second fetus was followed during pregnancy with ultrasound examinations. In the 20th week of gestation marked shortening of the extremities was found; a female infant showing the same radiologic bony malformations as the firstborn was born by cesarean section. These cases support the autosomal recessive inheritance and demonstrate the possibility of prenatal diagnosis in this type of micromelic dwarfism. (orig.)

  16. Complications arising in twin pregnancy: findings of prenatal ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Ah; Cho, Jeong Yeon; Lee, Young Ho; Song, Mi Jin; Min, Jee Yeon; Lee, Hak Jong; Han, Byoung Hee; Lee, Kyung Sang; Cho, Byung Jae; Chun, Yi Kyeong [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2003-03-01

    Multifetal gestations are high-risk pregnancies involving higher perinatal morbidity and mortality, and are subject to unique complications including twin oligohydramnios- polyhydramnios sequence, twin-to-twin transfusion syndrome, acardiac twins, conjoined twins, co-twin demise, and heterotopic pregnancies. The purpose of this study is to describe the prenatal ultrasonographic and pathologic findings of these complications.

  17. Hydrodynamic optimization of twin-skeg LNG ships by CFD and model testing

    Science.gov (United States)

    Kim, Keunjae; Tillig, Fabian; Bathfield, Nicolas; Liljenberg, Hans

    2014-06-01

    SSPA experiences a growing interest in twin skeg ships as one attractive green ship solution. The twin skeg concept is well proven with obvious advantages for the design of ships with full hull forms, restricted draft or highly loaded propellers. SSPA has conducted extensive hull optimizations studies of LNG ships of different size based on an extensive hull data base with over 7,000 models tested, including over 400 twin skeg hull forms. Main hull dimensions and different hull concepts such as twin skeg and single screw were of main interest in the studies. In the present paper, one twin skeg and one single screw 170 K LNG ship were designed for optimally selected main dimension parameters. The twin skeg hull was further optimized and evaluated using SHIPFLOW FRIENDSHIP design package by performing parameter variation in order to modify the shape and positions of the skegs. The finally optimized models were then built and tested in order to confirm the lower power demand of twin skeg designed compaed with the signle screw design. This paper is a full description of one of the design developments of a LNG twin skeg hull, from early dimensional parameter study, through design optimization phase towards the confirmation by model tests.

  18. Gestational Weight Gain and Peripartum Cardiomyopathy in a Twin Pregnancy

    Directory of Open Access Journals (Sweden)

    Hiroko Matsumiya

    2015-01-01

    Full Text Available Preeclamptic twin pregnancy with larger gestational weight gain (GWG is suggested to have a higher risk of peripartum cardiomyopathy (PPCM. This was true in a 5-year experience at a single center. A primiparous woman with twins and prepregnancy weight of 51.0 kg exhibited hypertension at gestational week (GW 32−6/7 and GWG of 18.3 kg (6.0 kg and 2.9 kg during the last four weeks and one week of gestation, resp. concomitant with generalized edema, gave birth at GW 34−4/7, developed proteinuria, cough, and dyspnea postpartum, and was diagnosed with preeclampsia and PPCM showing left ventricular ejection fraction of 34% and plasma BNP level of 1530 pg/mL. This was the only case of PPCM among 101 (12 with preeclampsia and 3266 women with twin and singleton pregnancies, respectively. Thus, PPCM occurred significantly more often in women with preeclamptic twin pregnancies than in women with singleton pregnancies (8.3% [1/12] versus 0.0% [0/3266], P=0.0355. This patient showed the greatest weight gain of 6.0 kg during the last four weeks of gestation and the greatest weight loss of 19.2 kg during one month postpartum among 90 women with twin deliveries at GW ≥ 32.

  19. Coupling Damage-Sensing Particles to the Digitial Twin Concept

    Science.gov (United States)

    Hochhalter, Jacob; Leser, William P.; Newman, John A.; Gupta, Vipul K.; Yamakov, Vesselin; Cornell, Stephen R.; Willard, Scott A.; Heber, Gerd

    2014-01-01

    The research presented herein is a first step toward integrating two emerging structural health management paradigms: digital twin and sensory materials. Digital twin is an emerging life management and certification paradigm whereby models and simulations consist of as-built vehicle state, as-experienced loads and environments, and other vehicle-specific history to enable high-fidelity modeling of individual aerospace vehicles throughout their service lives. The digital twin concept spans many disciplines, and an extensive study on the full domain is out of the scope of this study. Therefore, as it pertains to the digital twin, this research focused on one major concept: modeling specifically the as-manufactured geometry of a component and its microstructure (to the degree possible). The second aspect of this research was to develop the concept of sensory materials such that they can be employed within the digital twin framework. Sensory materials are shape-memory alloys that undergo an audible phase transformation while experiencing sufficient strain. Upon embedding sensory materials with a structural alloy, this audible transformation helps improve the reliability of crack detection especially at the early stages of crack growth. By combining these two early-stage technologies, an automated approach to evidence-based inspection and maintenance of aerospace vehicles is sought.

  20. Breast-Feeding Twins: Making Feedings Manageable

    Science.gov (United States)

    ... more than one baby? Here's help breast-feeding twins or other multiples, from getting positioned and ensuring ... babies who are born prematurely, as are many twins and higher order multiples. Breast milk is easier ...

  1. Risk of Oral Clefts in Twins

    DEFF Research Database (Denmark)

    Grosen, Dorthe; Bille, Camilla; Petersen, Inge

    2011-01-01

    BACKGROUND:: Small studies have indicated that twinning increases the risk of oral cleft. METHODS:: We used data from a Danish national population-based cohort study to investigate whether twinning was associated with isolated oral cleft, and to estimate the twin probandwise concordance rate...... and heritability. Twins (207 affected/130,710) and singletons (7766 affected/4,798,526) born from 1936 through 2004 in Denmark were ascertained by linkage among the Danish Facial Cleft Database, the Danish Twin Registry, and the Civil Registration System. We computed oral cleft prevalence and prevalence proportion...... ratio for twins versus singletons, stratified for 3 subphenotypes. Probandwise concordance rates and heritability for twins were estimated for 2 phenotypes-cleft lip with or without cleft palate (CL/P) and cleft palate (CP). RESULTS:: The prevalence of oral cleft was 15.8 per 10,000 twins and 16.6 per...

  2. Having Twins? How to Stay Healthy

    Science.gov (United States)

    ... Listen Español Text Size Email Print Share Having Twins? How to Stay Healthy Page Content Article Body ... the eyes of obstetricians. Many would call a twin pregnancy a high-risk pregnancy , but don’t ...

  3. Nike Twins Seven Seven: Nigerian Batik Artist.

    Science.gov (United States)

    LaDuke, Betty

    1987-01-01

    Chronicles the personal and professional life of Nike Twins Seven Seven (born 1951), a Nigerian batik artist, and her husband, Twins Seven Seven, a musician-artist, both of whom have received international acclaim. (BJV)

  4. Preterm twin gestation and cystic periventricular leucomalacia

    NARCIS (Netherlands)

    Resch, B; Jammernegg, A; Vollaard, E; Maurer, U; Mueller, WD; Pertl, B

    2004-01-01

    Objective: To identify risk factors for the development of cystic periventricular leucomalacia (PVL) in twin gestation. Design: Retrospective case-control study. Setting: Tertiary care university hospital, Department of Paediatrics, Division of Neonatology, Graz, Austria. Patients: Preterm twin gest

  5. Nike Twins Seven Seven: Nigerian Batik Artist.

    Science.gov (United States)

    LaDuke, Betty

    1987-01-01

    Chronicles the personal and professional life of Nike Twins Seven Seven (born 1951), a Nigerian batik artist, and her husband, Twins Seven Seven, a musician-artist, both of whom have received international acclaim. (BJV)

  6. 3D CFD analysis of a twin screw expander

    OpenAIRE

    Kovacevic, A.; S Rane

    2013-01-01

    Twin screw machines can be used as expanders for variety of applications. This paper describes how the performance of an oil free twin screw air expander of 3/5 lobe configuration was estimated by use of full 3D Computational Fluid Dynamics (CFD) applying a procedure similar to that used for screw compressors. The grid generator SCORG© was employed for pre-processing of the moving domains between the rotors while the stationary grids for the ports were derived from a commercial grid generator...

  7. Twins' injuries: genetic and environmental risks / twin research reports / human interest stories.

    Science.gov (United States)

    Segal, Nancy L

    2011-04-01

    The relative contributions of genetic and environmental factors to unintentional injuries are of interest to families with young twins. A recent study found that childhood injuries are explained mostly by child-specific environmental factors. Next, twin research reviews of the association between periodontal disease and cancer, secular trends in gestational age and birthweight, and language development in hearing and deaf co-twins are also summarized. Interesting reports of newborn twins, twin-like relationships, twin interactions and missed twin relationships are presented.

  8. The Fourth International Network of Twin Registries: Overview from Osaka/Research Reviews: Familial Fraternal Twinning; Twin Study of Masculine Faces; Physical Aggression and Epigenetics; Prenatal Education for Parents of Twins/Current Events: 2016 Guinness Book of World Records; Oldest Living Male Twins; Twins Reunited at Sixty-Nine; Panda Twins; Twins.com.

    Science.gov (United States)

    Segal, Nancy L

    2015-12-01

    The 4th International Network of Twin Registries (INTR) Consortium Meeting took place in Osaka, Japan, September 28-29, 2015. The venue was the Osaka Medical Center for Medical Innovation and Translational Research. An overview of presentations and other activities is provided. Next, 1930s research on familial fraternal twinning, preference for masculine faces, physical aggression and epigenetics, and a prenatal education program for parents of multiples are described. Current twin-related events include the 2016 Guinness Book of World Records (GWR), the oldest living male twins, newly reunited twins, the birth of panda twins and a controversial twin-based website.

  9. Detecting genes contributing to longevity using twin data

    Directory of Open Access Journals (Sweden)

    Begun Alexander

    2009-12-01

    Full Text Available Abstract Searching for genes contributing to longevity is a typical task in association analysis. A number of methods can be used for finding this association -- from the simplest method based on the technique of contingency tables to more complex algorithms involving demographic data, which allow us to estimate the genotype-specific hazard functions. The independence of individuals is the common assumption in all these methods. At the same time, data on related individuals such as twins are often used in genetic studies. This paper proposes an extension of the relative risk model to encompass twin data. We estimate the power and also discuss what happens if we treat the twin data using the univariate model.

  10. Do Twin Boundaries Always Strengthen Metal Nanowires?

    OpenAIRE

    Zhang Yongfeng; Huang Hanchen

    2008-01-01

    Abstract It has been widely reported that twin boundaries strengthen nanowires regardless of their morphology—that is, the strength of nanowires goes up as twin spacing goes down. This article shows that twin boundaries do not always strengthen nanowires. Using classical molecular dynamics simulations, the authors show that whether twin boundaries strengthen nanowires depends on the necessary stress for dislocation nucleation, which in turn depends on surface morphologies. When nanowire...

  11. Physical performance limitations in adolescent and adult survivors of childhood cancer and their siblings.

    Directory of Open Access Journals (Sweden)

    Corina S Rueegg

    Full Text Available PURPOSE: This study investigates physical performance limitations for sports and daily activities in recently diagnosed childhood cancer survivors and siblings. METHODS: The Swiss Childhood Cancer Survivor Study sent a questionnaire to all survivors (≥ 16 years registered in the Swiss Childhood Cancer Registry, who survived >5 years and were diagnosed 1976-2003 aged <16 years. Siblings received similar questionnaires. We assessed two types of physical performance limitations: 1 limitations in sports; 2 limitations in daily activities (using SF-36 physical function score. We compared results between survivors diagnosed before and after 1990 and determined predictors for both types of limitations by multivariable logistic regression. RESULTS: The sample included 1038 survivors and 534 siblings. Overall, 96 survivors (9.5% and 7 siblings (1.1% reported a limitation in sports (Odds ratio 5.5, 95%CI 2.9-10.4, p<0.001, mainly caused by musculoskeletal and neurological problems. Findings were even more pronounced for children diagnosed more recently (OR 4.8, CI 2.4-9.6 and 8.3, CI 3.7-18.8 for those diagnosed <1990 and ≥ 1990, respectively; p=0.025. Mean physical function score for limitations in daily activities was 49.6 (CI 48.9-50.4 in survivors and 53.1 (CI 52.5-53.7 in siblings (p<0.001. Again, differences tended to be larger in children diagnosed more recently. Survivors of bone tumors, CNS tumors and retinoblastoma and children treated with radiotherapy were most strongly affected. CONCLUSION: Survivors of childhood cancer, even those diagnosed recently and treated with modern protocols, remain at high risk for physical performance limitations. Treatment and follow-up care should include tailored interventions to mitigate these late effects in high-risk patients.

  12. Non-Random Sibling Cannibalism in the Marine Gastropod Crepidula coquimbensis.

    Directory of Open Access Journals (Sweden)

    Antonio Brante

    Full Text Available Sibling cannibalism is commonly observed in marine species. For instance, intrabrood cannibalism has been documented in marine gastropods with direct development, suggesting a relationship between embryo behavior and the evolution of life history strategies. However, there has been little effort to document the factors driving sibling cannibalism in marine species. The kin selection theory suggests that the level of relatedness plays an important role in cannibalism patterns. We examined Crepidula coquimbensis, a marine gastropod that broods and encloses its brooded offspring in capsules. Encapsulated embryos show sibling cannibalism and high levels of intracapsular multiple paternity. Given these features, cannibalistic behavior may be driven by kin-relatedness. To test this hypothesis, we constructed artificial aggregations of embryos to mimic three levels of relatedness: high, medium and low. For each category of aggregation, the cannibalism rate and benefits (i.e. size at hatching of surviving offspring were estimated. In addition, at the end of embryo development, we performed parentage analyses to determine if cannibalism was associated with the relatedness between cannibal and victim embryos. Our results show that the intensity of sibling cannibalism increased in aggregations characterized by the lowest level of relatedness. There were important benefits of cannibalism in terms of hatching cannibal size. In addition, cannibalism between embryos was not random: the variation in reproductive success between males increased over the course of the experiment and the effective number of fathers decreased. Altogether, these results suggest that polyandry may play an important role in the evolution of sibling cannibalism in C. coquimbensis and that kin selection may operate during early embryonic stages in this species.

  13. The effect of Swedish snuff (snus on offspring birthweight: a sibling analysis.

    Directory of Open Access Journals (Sweden)

    Sol Pía Juárez

    Full Text Available Current observational evidence indicates that maternal smoking during pregnancy is associated with reduced birthweight in offspring. However, less is known about the effect of smokeless tobacco on birthweight and about the possible mechanisms involved in this relationship. This paper studies the effect of Swedish smokeless tobacco (snus on offspring birthweight comparing the results obtained from a conventional linear regression analysis and from a quasi-experimental sibling design using a multilevel linear regression analysis. From the Swedish Medical Birth Register, we investigated 604,804 singletons born between 2002 and 2010. From them, we isolated 8,861 siblings from 4,104 mothers with discrepant snus-use habits (i.e., women who had at least one pregnancy during which they used snus and at least one other pregnancy in which they did not. The conventional analysis shows that continuous snus use throughout the pregnancy reduces birthweight in 47 g while quitting or relapsing snus has a minor and statistically non-significant effect (-6 g and -4 g, respectively. However, using a sibling analysis the effect observed for mothers who continue to use snus during pregnancy is less intense than that observed with previous conventional analyses (-20 g, and this effect is not statistically significant. Sibling analysis shows that quitting or relapsing snus use after the first trimester slightly reduces birthweight (14 g. However, this small change is not statistically significant. The sibling analysis provides strong causal evidence indicating that exposure to snus during pregnancy has a minor effect on birthweight reduction. Our findings provide a new piece of causal evidence concerning the effect of tobacco on birthweight and support the hypothesis that the harmful effect of smoking on birthweight is not mainly due to nicotine.

  14. Twins reunited: scientific and personal perspectives/twin research studies: multiple birth effects on IQ and body size; life style, muscles, and metabolism; monochorionic dizygotic twin with blood chimerism; amniocentesis for twins/twins in the media: identical doctors; freedom fighter for twins; twin scholarships; Auguste and Jean-Felix Piccard; twins born apart.

    Science.gov (United States)

    Segal, Nancy L; Mulligan, Christy A

    2014-04-01

    A reunion of 38-year-old female monozygotic twins took place in Daegu, South Korea, on January 14, 2014. Scientific and personal perspectives on this extraordinary event are provided. A review of timely twin research follows, covering the effects of multiple births on IQ and body size, lifestyle and physical fitness associations, a rare case of a dizygotic twin with blood chimerism and definitional issues surrounding amniocentesis-related loss in multiple birth pregnancies. Interesting and informative mention of twins in the media includes twin doctors, a twin freedom fighter, the availability of college scholarships for twins, a new book about the Piccard family (two of whose members were twins), and co-twins born before and after the new year. A follow-up to a previous mention of identical twin biatheletes is also provided.

  15. Influence of Siblings on Out-of-School Reading Practices

    Science.gov (United States)

    Knoester, Matthew; Plikuhn, Mari

    2016-01-01

    This study draws on interviews with 26 individuals who attained an advanced degree and whose parents did not attend university and who reported having at least one older sibling. Participants were asked about independent reading practices in their youth and the reading practices of their older siblings. Participants reported many memories of their…

  16. Treating the sibling subsystem: an adjunct of divorce therapy.

    Science.gov (United States)

    Schibuk, M

    1989-04-01

    Sibling therapy, frequently overlooked as a method of treatment, is particularly appropriate in situations that require a deliberate focus on the "unit of continuity," or the subsystem that remains intact during a process of family reorganization. For this and other reasons it can be an effective tool in treating children of divorce. A case illustrating this use of sibling therapy is presented.

  17. Psychosocial Characteristics of Preschool Siblings of Handicapped and Nonhandicapped Children.

    Science.gov (United States)

    Lobato, Debra; And Others

    1987-01-01

    The study examined psychosocial characteristics of 24 siblings of handicapped children (ages 3-7) in relation to a control group of 22 siblings of nonhandicapped children. Results indicated no statistically significant differences between groups on measures of perceived self-competence and acceptance, understanding of developmental disabilities,…

  18. Birth Order, Sibling IQ Differences, and Family Relations.

    Science.gov (United States)

    Pfouts, Jane H.

    The differential impact of birth order and IQ on sibling roles were examined with particular interest focused on achievement outcomes. Subjects were a stratified sample of 37 pairs of near-in-age siblings, all within the normal range in personality and IQ, but differing significantly in scores on the Slosson IQ Test. Results indicate that when the…

  19. Class Origin and Sibling Similarities in Long-run Income

    DEFF Research Database (Denmark)

    Andrade, Stefan Bastholm

    2016-01-01

    an analytical class approach to sibling studies by analysing how much of the influence that siblings share in their long-term income results from class origin. Data are from Statistics Denmark and consist of 290,399 individuals born between 1963 and 1973. Models are estimated which – in addition to parents...

  20. Latino Adolescents' Academic Motivation: The Role of Siblings

    Science.gov (United States)

    Alfaro, Edna C.; Umana-Taylor, Adriana J.

    2010-01-01

    Guided by an ecological perspective, two competing models were tested to examine how sibling relationship quality directly predicted or interacted with academic support from siblings to predict Latino adolescents' academic motivation (N = 258). Gender differences were examined utilizing multiple group analysis in structural equation modeling.…

  1. Sibling Incest: Reports from Forty-One Survivors

    Science.gov (United States)

    Carlson, Bonnie E.; Maciol, Katherine; Schneider, Joanne

    2006-01-01

    An exploratory study was conducted with a convenience sample of 41 adult survivors of sibling incest using a retrospective survey design. Participants were interviewed about their childhood sexual experiences with a sibling. Most participants reported vaginal or oral intercourse and coercive experiences. Half of the sample reported sexual…

  2. Sibling Socialization: The Effects of Stressful Life Events and Experiences

    Science.gov (United States)

    Conger, Katherine J.; Stocker, Clare; McGuire, Shirley

    2009-01-01

    Stressful life events and experiences may disrupt the typical day-to-day interactions between sisters and brothers that provide the foundation of sibling socialization. This chapter examines four experiences that may affect patterns of sibling interaction: parental marital conflict, parental divorce and remarriage, foster care placement, and a…

  3. Weismann-Netter-Stuhl syndrome in two siblings

    Energy Technology Data Exchange (ETDEWEB)

    Yekeler, Ensar; Ozdemir, Candan; Acunas, Gulden [Istanbul Faculty of Medicine, Department of Radiology, Istanbul University, Capa, Istanbul (Turkey); Gokalp, Selman; Yildirim, Abdurrahman; Bas, Firdevs; Gunoz, Hulya [Istanbul Faculty of Medicine, Department of Pediatric Endocrinology, Istanbul (Turkey)

    2005-03-01

    Cases of Weismann-Netter-Stuhl syndrome involving the upper extremities and affecting siblings have rarely been reported. We present the radiological findings of Weismann-Netter-Stuhl syndrome in two siblings, with upper extremity involvement in one of them. (orig.)

  4. Proactive and reactive sibling aggression and adjustment in adolescence.

    Science.gov (United States)

    Tucker, Corinna Jenkins; Van Gundy, Karen T; Wiesen-Martin, Desireé; Hiley Sharp, Erin; Rebellon, Cesar J; Stracuzzi, Nena F

    2015-03-01

    Existing research on aggression tends to narrowly focus on peers; less is known about sibling aggression, most likely due to its historical acceptance. Aggression is characterized by its forms (i.e., physical vs. social or relational aggression) and its functions (i.e., the motivations behind the aggressive act and categorized as proactive vs. reactive aggression). We use data from a two-wave study of middle (n = 197; M age = 12.63 years at Wave 1) and older (n = 159; M age = 16.50 years at Wave 1) adolescents to assess the extent to which proactive and reactive functions of sibling aggression make unique or conditional contributions to adolescent adjustment (i.e., depression, delinquency, and substance use). We find that proactive sibling aggression increases risk for problem substance use and delinquent behavior, reactive sibling aggression increases risk for depressed mood and delinquent behavior, and such results are observed even with statistical adjustments for sociodemographic and family variables, stressful life events, and prior adjustment. Few conditional effects of proactive or reactive sibling aggression by sex or grade are observed; yet, for all three outcomes, the harmful effects of reactive sibling aggression are strongest among adolescents who report low levels of proactive sibling aggression. The results speak to the importance of understanding the proactive and reactive functions of sibling aggressive behaviors for adolescent adjustment.

  5. Compensatory Effects of Sibling Support in Preadolescence and Adolescence.

    Science.gov (United States)

    Milevsky, Avidan; Levitt, Mary J.

    The current study is an examination of how support from siblings relates to academic competence in early adolescence, with a focus on the compensatory effects of sibling support. Participants were 694 African-American, European-American, and Hispanic-American students, ranging in age from 11 to 15. Participants were interviewed in school regarding…

  6. Influence of Siblings on Out-of-School Reading Practices

    Science.gov (United States)

    Knoester, Matthew; Plikuhn, Mari

    2016-01-01

    This study draws on interviews with 26 individuals who attained an advanced degree and whose parents did not attend university and who reported having at least one older sibling. Participants were asked about independent reading practices in their youth and the reading practices of their older siblings. Participants reported many memories of their…

  7. Associations between Family Communication Patterns, Sibling Closeness, and Adoptive Status

    Science.gov (United States)

    Samek, Diana R.; Rueter, Martha A.

    2011-01-01

    Previous research has demonstrated the protective effect of family and sibling closeness on child adjustment, but fewer studies have investigated how closeness is promoted within families. Guided by Family Communication Patterns Theory, we tested the association between family communication and sibling emotional and behavioral closeness, and…

  8. Caregiving, perceptions of maternal favoritism, and tension among siblings.

    Science.gov (United States)

    Suitor, J Jill; Gilligan, Megan; Johnson, Kaitlin; Pillemer, Karl

    2014-08-01

    Studies of later-life families have revealed that sibling tension often increases in response to parents' need for care. Both theory and research on within-family differences suggest that when parents' health declines, sibling relations may be affected by which children assume care and whether siblings perceive that the parent favors some offspring over others. In the present study, we explore the ways in which these factors shape sibling tension both independently and in combination during caregiving. In this article, we use data collected from 450 adult children nested within 214 later-life families in which the offspring reported that their mothers needed care within 2 years prior to the interview. Multilevel analyses demonstrated that providing care and perceiving favoritism regarding future caregiving were associated with sibling tension following mothers' major health events. Further, the effects of caregiving on sibling tension were greater when perceptions of favoritism were also present. These findings shed new light on the conditions under which adult children are likely to experience high levels of sibling tension during caregiving. Understanding these processes is important because siblings are typically the individuals to whom caregivers are most likely to turn for support when assuming care of older parents, yet these relationships are often a major source of interpersonal stress. © The Author 2013. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Adult Sibling Relationships with Brothers and Sisters with Severe Disabilities

    Science.gov (United States)

    Rossetti, Zach; Hall, Sarah

    2015-01-01

    The purpose of this qualitative study was to examine perceptions of adult sibling relationships with a brother or sister with severe disabilities and the contexts affecting the relationships. Adult siblings without disabilities (N = 79) from 19 to 72 years of age completed an online survey with four open-ended questions about their relationship…

  10. Siblings of the Child with a Life-Threatening Illness.

    Science.gov (United States)

    Sourkes, Barbara M.

    1987-01-01

    The experience of siblings of a child with a life-threatening illness may be seen at the juncture of the following perspectives: (1) the family system; (2) a focus on living rather than on dying; and (3) a view toward positive adaptation rather than toward psychopathology. The most critical focus is on the sibling-patient relationship itself. (BJV)

  11. Outcomes in Adult Life among Siblings of Individuals with Autism

    Science.gov (United States)

    Howlin, Patricia; Moss, Philippa; Savage, Sarah; Bolton, Patrick; Rutter, Michael

    2015-01-01

    Little is known about adult siblings of individuals with autism. We report on cognitive, social and mental health outcomes in 87 adult siblings (mean age 39 years). When younger all had been assessed either as being "unaffected" by autism (n = 69) or as meeting criteria for the "Broader Autism Phenotype" (BAP, n = 18). As…

  12. Support Between Siblings and Between Friends : Two Worlds Apart?

    NARCIS (Netherlands)

    Voorpostel, Marieke; Lippe, Tanja van der

    2007-01-01

    This research examines whether siblings and friends resemble each other in supportive behavior. Using a Dutch national sample of 6,289 individuals containing 12,578 relationships with siblings and friends, we investigated the relative importance of gender composition, geographical proximity, relatio

  13. Congenital varicella syndrome in a monochorionic diamniotic twin pregnancy

    Directory of Open Access Journals (Sweden)

    Vania A Villota

    2014-01-01

    Full Text Available Congenital varicella syndrome encompasses a broad spectrum of malformations present in children of mothers who developed chickenpox during the first 20 weeks of gestation. We report a case of a monochorionic diamniotic twin pregnancy, with maternal exposure to chickenpox during the thirteenth week of gestation, which produced one symptomatic and one healthy child.

  14. Renal Urologic Anomalies Presenting In Adult Identical Twins

    Directory of Open Access Journals (Sweden)

    Robert A. Edelstein

    2004-01-01

    Full Text Available Two sets of identical adult twins recently presented to our hospital. In one case, the patients demonstrated (ipsilateral renal agenesis. In the other, the patients presented approximately one year apart with symptomatic (ipsilateral ureteropelvic junction obstructions. Although the literature suggests a few reports of this type in the pediatric and newborn population, the authors are unaware of similar reports in adults.

  15. Multiple rectal carcinoid tumors in monozygotic twins.

    Science.gov (United States)

    Doi, Momoko; Ikawa, Osamu; Taniguchi, Hiroki; Kawamura, Takuji; Katsura, Kanade

    2016-08-01

    We report multiple rectal carcinoid tumors in monozygotic twins who, respectively, had 42 and 36 carcinoid tumors in the lower rectum. This is the first report about carcinoid tumors in monozygotic twins. Both twins developed a similar number of rectal carcinoids with a similar distribution. Investigation of their genetic background may provide information about the origin of these tumors.

  16. Postpartum Mental State of Mothers of Twins

    Science.gov (United States)

    Brantmüller, Éva; Gyúró, Mónika; Galgán, Kitti; Pakai, Annamária

    2016-01-01

    Twin birth is a relevant risk factor for postnatal depression (PND). The primary objective of our study is to reveal the prevalence of suspected cases of depression and to identify some background factors among mothers of twins. We applied convenience sampling method within a retrospective, quantitative study among mothers given birth to twins for…

  17. A RARE CASE OF ACARDIAC TWIN

    OpenAIRE

    Padmaja; Nirmala,

    2015-01-01

    Fetus Acardiacus is a very rare manifestation of twin gestation . This happens due to TRAP sequence . That is Twin reversed arterial perfusion . In this case an amorphous mass was seen on a routine antenatal scan and followed as there was a live twin also . The case report highlights the importance of careful scanning and ...

  18. MIR phasing using merohedrally twinned crystals

    NARCIS (Netherlands)

    Terwisscha van Scheltinga, Anke C.; Valegård, Karin; Hajdu, Janos; Andersson, Inger

    2003-01-01

    Merohedral twinning is a crystal-growth disorder that seriously hinders the determination of macromolecular crystal structures by isomorphous replacement. The strategies used in the structures solved so far are discussed. Several methods can be used to determine the extent of twinning, the twin frac

  19. Epigenetic Epidemiology of Complex Diseases Using Twins

    DEFF Research Database (Denmark)

    Tan, Qihua

    2013-01-01

    through multiple epigenetic mechanisms. This paper reviews the new developments in using twins to study disease-related epigenetic alterations, links them to lifetime environmental exposure with a focus on the discordant twin design and proposes novel data-analytical approaches with the aim of promoting...... a more efficient use of twins in epigenetic studies of complex human diseases....

  20. [The diagnostic algorithm in twin pregnancy].

    Science.gov (United States)

    Ropacka-Lesiak, Mariola; Szaflik, Krzysztof; Breborowicz, Grzegorz H

    2015-03-01

    This paper presents the diagnostic algorithm in twin pregnancy. The most important sonographic parameters in the assessment of twins have been discussed. Moreover, the most significant complications of twin pregnancy as well as diagnostic possibilities and management, have been also presented and defined.