A national Swedish longitudinal twin-sibling study of criminal convictions from adolescence through early adulthood.

Science.gov (United States)

Kendler, Kenneth S; Lönn, Sara Larsson; Maes, Hermine H; Morris, Nancy A; Lichtenstein, Paul; Sundquist, Jan; Sundquist, Kristina

2015-06-01

Prior twin and adoption studies have demonstrated the importance of both genetic and shared environmental factors in the etiology of criminal behavior (CB). However, despite substantial interest in life-course theories of CB, few genetically informative studies have examined CB in a developmental context. In 69,767 male-male twin pairs and full-sibling pairs with ≤ 2 years' difference in age, born 1958-1976 and ascertained from the Swedish Twin and Population Registries, we obtained information on all criminal convictions from 1973 to 2011 from the Swedish Crime Register. We fitted a Cholesky structural model, using the OpenMx package, to CB in these pairs over three age periods: 15-19, 20-24, and 25-29. The Cholesky model had two main genetic factors. The first began at ages 15-19 and declined in importance over development. The second started at ages 20-24 and was stable over time. Only one major shared environmental factor was seen, beginning at ages 15-19. Heritability for CB declined from ages 15-29, as did shared environmental effects, although at a slower rate. Genetic risk factors for CB in males are developmentally dynamic, demonstrating both innovation and attenuation. These results are consistent with theories of adolescent-limited and life-course persistent CB subtypes. Heritability for CB did not increase over time as might be predicted from active gene-environmental correlation. However, consistent with expectation, the proportion of variability explained by shared environmental effects declined slightly as individuals aged and moved away from their original homes and neighborhoods.

Theory of Mind May Be Contagious, but You Don't Catch It From Your Twin

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Cassidy, Kimberly Wright; Fineberg, Deborah Shaw; Brown, Kimberly; Perkins, Alexis

2005-01-01

The theory-of-mind abilities of twins, children with nontwin siblings, and only children were compared to investigate further the link between number and type of siblings and theory-of-mind abilities. Three- to 5-year-old children with nontwin siblings outperformed both only children and twins with no other siblings, twins who also had other…

Reciprocal Longitudinal Associations Between Adolescent Twin Gambling and Delinquency.

Science.gov (United States)

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

2015-12-01

This study examined sibling influence over gambling involvement and delinquency in a sample of 628 twins (151 male dyads, 163 female dyads). Self-reports of gambling involvement and delinquency were collected for each twin at ages 13, 14 and 15 years. Results revealed evidence of between-twin influence. Higher levels of an adolescent's delinquency predicted an increase in his or her co-twin's delinquency from age 13 to age 14 and from age 14 to age 15. In contrast, gambling behavior was unaffected by the co-twin's gambling involvement. Within-twins, higher initial levels of delinquency predicted a subsequent increase in gambling behavior from age 13 to age 14 and again from age 14 to age 15, and higher initial levels of gambling involvement predicted an increase in delinquency from age 14 to age 15. Between and within siblings effects are discussed in light of the scant literature on (a) sibling influence on gambling, and (b) the links between gambling and delinquency.

Development Genetic Analysis of General Cognitive Ability from 1 to 12 Years in a Sample of Adoptees, Biological Siblings, and Twins.

Science.gov (United States)

Bishop, E. G.; Cherny, Stacey S.; Corley, Robin; Plomin, Robert; DeFries, John C.; Hewitt, John K.

2003-01-01

Studied continuity and change in general cognitive ability from infancy to adolescence in adoptees (107 children), biological siblings (87 pairs), and twins (224 monozygotic and 189 dyzygotic pairs). Findings generally support previous findings about genetic and environmental factors, with the exception that in the transition to adolescence,…

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...... that is claimed to be more fundamental and general, but which, we believe, has no practical biological meaning for the evolution of eusociality. Nowak et al. overlook the robust empirical observation that eusociality has only arisen in clades where mothers are associated with their full-sibling offspring; that is......, in families where the average relatedness of offspring to siblings is as high as to their own offspring, independent of population structure or ploidy. We believe that this omission makes the paper largely irrelevant for understanding the evolution of eusociality....

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.

Monozygotic twins with discordant intestinal rotation

International Nuclear Information System (INIS)

Smith, Vance L.; Nwomeh, Benedict C.; Long, Frederick

2006-01-01

Previous case reports have suggested a strong concordance of intestinal malrotation among identical twins. This has led to the recommendation that the asymptomatic twin undergo screening when malrotation is discovered in the identical sibling. We present a case of monozygotic twins in which one twin presented with intestinal malrotation with midgut volvulus while the other twin was found to have normal gastrointestinal anatomy. (orig.)

Monozygotic twins with discordant intestinal rotation

Energy Technology Data Exchange (ETDEWEB)

Smith, Vance L.; Nwomeh, Benedict C. [Ohio State University College of Medicine and Public Health, Department of Pediatric Surgery, Columbus Children' s Hospital, Columbus, OH (United States); Long, Frederick [Ohio State University College of Medicine and Public Health, Department of Radiology, Columbus Children' s Hospital, Columbus, OH (United States)

2006-04-15

Previous case reports have suggested a strong concordance of intestinal malrotation among identical twins. This has led to the recommendation that the asymptomatic twin undergo screening when malrotation is discovered in the identical sibling. We present a case of monozygotic twins in which one twin presented with intestinal malrotation with midgut volvulus while the other twin was found to have normal gastrointestinal anatomy. (orig.)

Causes of individual differences in adolescent optimism: a study in Dutch twins and their siblings.

Science.gov (United States)

Mavioğlu, Rezan Nehir; Boomsma, Dorret I; Bartels, Meike

2015-11-01

The aim of this study was to investigate the degree to which genetic and environmental influences affect variation in adolescent optimism. Optimism (3 items and 6 items approach) and pessimism were assessed by the Life Orientation Test-Revised (LOT-R) in 5,187 adolescent twins and 999 of their non-twin siblings from the Netherlands Twin Register (NTR). Males reported significantly higher optimism scores than females, while females score higher on pessimism. Genetic structural equation modeling revealed that about one-third of the variance in optimism and pessimism was due to additive genetic effects, with the remaining variance being explained by non-shared environmental effects. A bivariate correlated factor model revealed two dimensions with a genetic correlation of -.57 (CI -.67, -.47), while the non-shared environmental correlation was estimated to be -.21 (CI -.25, -.16). Neither an effect of shared environment, non-additive genetic influences, nor quantitative sex differences was found for both dimensions. This result indicates that individual differences in adolescent optimism are mainly accounted for by non-shared environmental factors. These environmental factors do not contribute to the similarity of family members, but to differences between them. Familial resemblance in optimism and pessimism assessed in adolescents is fully accounted for by genetic overlap between family members.

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.

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.

Attractiveness Differences Between Twins Predicts Evaluations of Self and Co-Twin

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Principe, Connor P.; Rosen, Lisa H.; Taylor-Partridge, Teresa; Langlois, Judith H.

2012-01-01

One of the most consistent findings in psychology shows that people prefer and make positive attributions about attractive compared with unattractive people. The goal of the current study was to determine the power of attractiveness effects by testing whether these social judgments are made where attractiveness differences are smallest: between twins. Differences in facial attractiveness predicted twins’ evaluations of self and their co-twin (n = 158; 54 male). In twin pairs, the more attractive twin judged their less attractive sibling as less physically attractive, athletic, socially competent, and emotionally stable. The less attractive twin did the reverse. Given that even negligible differences in facial attractiveness predicted self and co-twin attitudes, these results provide the strongest test yet of appearance-based stereotypes. PMID:23467329

Genetic Linkage and Association Analysis for Loneliness in Dutch Twin and Sibling Pairs Points to a Region on Chromosome 12q23–24

NARCIS (Netherlands)

Boomsma, D.I.; Cacioppo, J.T.; Slagboom, P.E.; Posthuma, D.

2006-01-01

We obtained evidence from a large study in Dutch twins (N = 8387) and siblings (N = 2295) that variation in loneliness has a genetic component. The heritability estimate for loneliness, which was assessed as an ordinal trait, was 40% and did not differ between males and females. There were 682

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…

The Siblings With Ischemic Stroke Study (SWISS Protocol

Directory of Open Access Journals (Sweden)

Hardy John

2002-02-01

Full Text Available Abstract Background Family history and twins studies suggest an inherited component to ischemic stroke risk. Candidate gene association studies have been performed but have limited capacity to identify novel risk factor genes. The Siblings With Ischemic Stroke Study (SWISS aims to conduct a genome-wide scan in sibling pairs concordant or discordant for ischemic stroke to identify novel genetic risk factors through linkage analysis. Methods Screening at multiple clinical centers identifies patients (probands with radiographically confirmed ischemic stroke and a family history of at least 1 living full sibling with stroke. After giving informed consent, without violating privacy among other family members, the proband invites siblings concordant and discordant for stroke to participate. Siblings then contact the study coordinating center. The diagnosis of ischemic stroke in potentially concordant siblings is confirmed by systematic centralized review of medical records. The stroke-free status of potentially discordant siblings is confirmed by validated structured telephone interview. Blood samples for DNA analysis are taken from concordant sibling pairs and, if applicable, from 1 discordant sibling. Epstein-Barr virus-transformed lymphoblastoid cell lines are created, and a scan of the human genome is planned. Discussion Conducting adequately powered genomics studies of stroke in humans is challenging because of the heterogeneity of the stroke phenotype and the difficulty of obtaining DNA samples from clinically well-characterized members of a cohort of stroke pedigrees. The multicentered design of this study is intended to efficiently assemble a cohort of ischemic stroke pedigrees without invoking community consent or using cold-calling of pedigree members.

A twin-family study of general IQ.

NARCIS (Netherlands)

van Leeuwen, M.; van den Berg, S.M.; Boomsma, D.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

A twin-family study of general IQ

NARCIS (Netherlands)

Leeuwen, M; van den Berg, Stéphanie Martine; Boomsma, D.I.

2008-01-01

In this paper we assess the presence of assortative mating, gene¿environment interaction and the heritability of intelligence in childhood usinga twin family design with twins, their siblings and parents from 112 families. We evaluate two competing hypotheses about the cause of assortativemating in

New insights into the endophenotypic status of cognition in bipolar disorder: genetic modelling study of twins and siblings.

Science.gov (United States)

Georgiades, Anna; Rijsdijk, Fruhling; Kane, Fergus; Rebollo-Mesa, Irene; Kalidindi, Sridevi; Schulze, Katja K; Stahl, Daniel; Walshe, Muriel; Sahakian, Barbara J; McDonald, Colm; Hall, Mei-Hua; Murray, Robin M; Kravariti, Eugenia

2016-06-01

Twin studies have lacked statistical power to apply advanced genetic modelling techniques to the search for cognitive endophenotypes for bipolar disorder. To quantify the shared genetic variability between bipolar disorder and cognitive measures. Structural equation modelling was performed on cognitive data collected from 331 twins/siblings of varying genetic relatedness, disease status and concordance for bipolar disorder. Using a parsimonious AE model, verbal episodic and spatial working memory showed statistically significant genetic correlations with bipolar disorder (rg = |0.23|-|0.27|), which lost statistical significance after covarying for affective symptoms. Using an ACE model, IQ and visual-spatial learning showed statistically significant genetic correlations with bipolar disorder (rg = |0.51|-|1.00|), which remained significant after covarying for affective symptoms. Verbal episodic and spatial working memory capture a modest fraction of the bipolar diathesis. IQ and visual-spatial learning may tap into genetic substrates of non-affective symptomatology in bipolar disorder. © The Royal College of Psychiatrists 2016.

Psychological Implications of Motherhood and Fatherhood in Midlife: Evidence from Sibling Models

Science.gov (United States)

Pudrovska, Tetyana

2008-01-01

Using data from 4,744 full, twin, half-, adopted, and stepsiblings in the Wisconsin Longitudinal Study, I examine psychological consequences of motherhood and fatherhood in midlife. My analysis includes between-family models that compare individuals across families and within-family models comparing siblings from the same family to account for…

A sibling based design to quantify genetic and shared environmental effects of venous thromboembolism in Sweden.

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Zöller, Bengt; Ohlsson, Henrik; Sundquist, Jan; Sundquist, Kristina

2017-01-01

Few large studies have examined the heritability of venous thromboembolism (VTE). Moreover, twin studies have been suggested to overestimate heritability. The aim of the present study was to determine the heritability nationwide in the general Swedish population using full siblings and half-siblings. VTE was defined using the Swedish patient register. Full sibling (FS) and half-sibling (HS) pairs born 1950-1990 were obtained from the Swedish Multi-generation Register. A maximum of 5years age difference was allowed. We also required that the individuals within the pair should reside in the same household for at least 8years or not at all (0years) before the youngest turned 16. Information about sibling pair residence within the same household, small residential area, and municipality was obtained from Statistics Sweden. We assumed three potential sources of liability to VTE: additive genetic (A), shared (or common/familial) environment (C), and unique environment (E) components. Totally 881,206 FS pairs and 95,198 HS pairs were included. The full model predicted heritability for VTE with 47% for males and 40% for females. Environmental factors shared by siblings contributed to 0% of the variance in liability for both sexes, and unique environment (E) components accounted for 53% in males and 60% in females. The high heritability of VTE risk indicates that genetic susceptibility plays a substantial role for VTE in the Swedish general population. Overestimation of heritability from twin studies is not likely. The proportion of the variance attributable to shared familial environment factors is small. Subject codes: Genetics, epidemiology, thrombosis, cardiovascular disease, embolism. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bisphenol A induces oxidative stress and mitochondrial dysfunction in lymphoblasts from children with autism and unaffected siblings.

Science.gov (United States)

Kaur, Kulbir; Chauhan, Ved; Gu, Feng; Chauhan, Abha

2014-11-01

Autism is a behaviorally defined neurodevelopmental disorder. Although there is no single identifiable cause for autism, roles for genetic and environmental factors have been implicated in autism. Extensive evidence suggests increased oxidative stress and mitochondrial dysfunction in autism. In this study, we examined whether bisphenol A (BPA) is an environmental risk factor for autism by studying its effects on oxidative stress and mitochondrial function in the lymphoblasts. When lymphoblastoid cells from autistic subjects and age-matched unaffected sibling controls were exposed to BPA, there was an increase in the generation of reactive oxygen species (ROS) and a decrease in mitochondrial membrane potential in both groups. A further subdivision of the control group into two subgroups-unaffected nontwin siblings and twin siblings-showed significantly higher ROS levels without any exposure to BPA in the unaffected twin siblings compared to the unaffected nontwin siblings. ROS levels were also significantly higher in the autism vs the unaffected nontwin siblings group. The effect of BPA on three important mtDNA genes-NADH dehydrogenase 1, NADH dehydrogenase 4, and cytochrome b-was analyzed to observe any changes in the mitochondria after BPA exposure. BPA induced a significant increase in the mtDNA copy number in the lymphoblasts from the unaffected siblings group and in the unaffected twin siblings group vs the unaffected nontwin siblings. In all three genes, the mtDNA increase was seen in 70% of the subjects. These results suggest that BPA exposure results in increased oxidative stress and mitochondrial dysfunction in the autistic subjects as well as the age-matched sibling control subjects, particularly unaffected twin siblings. Therefore, BPA may act as an environmental risk factor for autism in genetically susceptible children by inducing oxidative stress and mitochondrial dysfunction. Copyright © 2014 Elsevier Inc. All rights reserved.

Appetite and growth: a longitudinal sibling analysis.

Science.gov (United States)

van Jaarsveld, Cornelia H M; Boniface, David; Llewellyn, Clare H; Wardle, Jane

2014-04-01

Identifying early markers of future obesity risk can help target preventive interventions. Several studies have shown that a heartier appetite in infancy is a risk factor for more rapid weight gain, but to date no investigations have been able to rule out familial confounding. To use a sibling design (data from same-sex, dizygotic twin pairs) to test the hypothesis that sibling differences in infant appetite predicted differential weight gain during childhood. Gemini is a population-based twin cohort among the general United Kingdom population born between March 1, 2007, and December 15, 2007. Growth trajectories were analyzed from birth to age 15 months. Appetite-discordant pairs were selected from 800 nonidentical, same-sex twin pairs. Appetite during the first 3 months of life was assessed with the food responsiveness (FR) and satiety responsiveness (SR) subscales from the Baby Eating Behaviour Questionnaire. Discordance was defined as a within-pair difference of at least 1 SD. A mean of 11.5 weight measurements per child were available between birth and age 15 months. Multilevel models, adjusted for sex and birth weight, compared growth curves for the higher-appetite vs lower-appetite twins. In total, 172 pairs were discordant for SR and 121 pairs for FR. Within-pair analyses showed that those with higher FR and those with lower SR grew faster than their sibling. At age 6 months, those with higher FR were 654 (95% CI, 395-913) g heavier and at age 15 months were 991 (95% CI, 484-1498) g heavier. For sibling pairs discordant for SR, the weight differences between siblings were 637 (95% CI, 438-836) g at age 6 months and 918 (95% CI, 569-1267) g at age 15 months. A heartier appetite (indexed with higher FR or lower SR) in early infancy is prospectively associated with more rapid growth up to age 15 months in a design controlling for potential familial confounding, supporting a causal role for appetite in childhood weight gain. Appetite could be an early marker

Intra-uterine exposure to dual fetal programming sequences among surviving co-twins.

Science.gov (United States)

Salihu, Hamisu M; Ibrahimou, Boubakari; Dagne, Getachew A

2011-01-01

The dynamics of fetal programming following in utero demise of a co-twin are poorly understood. The authors examined fetal programming using a unique application of the change-point analysis method, and identified two types of fetal programming that occurred when a viable twin sibling died in utero, while the co-twin survived. In one type, the initial twin fetal programming trajectory was maintained while in a subset of surviving co-twins a "switch" from a twin to a singleton fetal program (dual fetal programming exposure) was observed. The results suggest that the timing in utero of conversion from a twin to a singleton programming pattern occurred slightly earlier among opposite-sex than in same-sex surviving co-twins. For the conversion from a twin to a singleton program to happen, the surviving co-twin must have attained a "critical mass" when the twin sibling died. Whereas, for same-sex surviving co-twins the critical mass for conversion was the 80th percentile of gestational-age specific birth weight, opposite-sex surviving co-twins converted at a lower critical mass (70th percentile). These novel findings warrant further study to confirm the new hithertofore unknown phenomenon of dual fetal programming sequence, and to determine the implications in terms of subsequent morbidity or mortality during infancy, childhood and adult life.

Socio-psycho-historical observation on the twin. Sampling methods and case study of the atomic bomb exposed twins

Energy Technology Data Exchange (ETDEWEB)

Watanabe, S; Satow, Y; Ueoka, Hiroshi; Munaka, M; Kurihara, M [Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology

1980-07-01

The so-called ''twin control study'', mainly on the monozygotic twins one of which was A-bomb exposed and the other was non-exposed were carried out. Sampling was conducted utilizing the materials as follows: 1) The survey on casualities of A-bomb exposed families in Hiroshima which was undertaken in 1946. 2) The survey of A-bomb survivors in 1965. 3) A-bomb exposed family survey conducted between 1973 to 1975. 4) Investigations of A-bomb victims exposed in the proximal areas from the hypocenter. From the above mentioned materials 470 pairs were selected, of which 220 were exposed. Among them 172 pairs were twins of the same sex. Female and male pair were also employed. In one case they were exposed, while the others were nonexposed. Two pairs were examined under the following methods: 1) Depth interview to ascertain familial casualities with reference to the family life cycle. 2) Socio-historical research. 3) Motoaki's Jinkaku Shindan Kensa (Modified Rorschach test by H. Motoaki), and T.A.T. test. Results obtained were summarized as follows: 1) Both pairs of twins were of similar appearance and personality traits, and had a strong feeling of companionship for each other. 2) In family relationships, the persons studied were very conscious of the role expectations of elder and younger siblings in the twin pairs. 3) Through depth interviews and projective tests, A-bomb exposed pairs still showed deep psychological stresses, resulting from the A-bomb disaster. 4) Both among the exposed twins and within the nonexposed control group twin siblings had a close feeling of companionship for each other. However, nonexposed twins could not understand the psychological experience of twins who had been subjected to the atomic disaster.

Age of Onset in Concordant Twins and Other Relative Pairs With Multiple Sclerosis

OpenAIRE

Sadovnick, A. Dessa; Yee, Irene M.; Guimond, Colleen; Reis, Jacques; Dyment, David A.; Ebers, George C.

2009-01-01

The ages of onset in multiple sclerosis cases span more than 7 decades. Data are presented for affected relative pairs from a Canadian population base of 30,000 multiple sclerosis index cases (1993?2008). The effects of genetic sharing, parent of origin, intergenerational versus collinear differences, and gender on the ages of onset were evaluated in the following concordant pairs: monozygotic twins (n?=?29), dizygotic twins (n?=?10), siblings (n?=?614), first cousins (n?=?405), half siblings...

Socio-psycho-historical observation on the twin

International Nuclear Information System (INIS)

Watanabe, Shoji; Satow, Yukio; Ueoka, Hiroshi; Munaka, Masaki; Kurihara, Minoru

1980-01-01

The so-called ''twin control study'', mainly on the monozygotic twins one of which was A-bomb exposed and the other was non-exposed were carried out. Sampling was conducted utilizing the materials as follows: 1) The survey on casualities of A-bomb exposed families in Hiroshima which was undertaken in 1946. 2) The survey of A-bomb survivors in 1965. 3) A-bomb exposed family survey conducted between 1973 to 1975. 4) Investigations of A-bomb victims exposed in the proximal areas from the hypocenter. From the above mentioned materials 470 pairs were selected, of which 220 were exposed. Among them 172 pairs were twins of the same sex. Female and male pair were also employed. In one case they were exposed, while the others were nonexposed. Two pairs were examined under the following methods: 1) Depth interview to ascertain familial casualities with reference to the family life cycle. 2) Socio-historical research. 3) Motoaki's Jinkaku Shindan Kensa (Modified Rorschach test by H. Motoaki), and T.A.T. test. Results obtained were summarized as follows: 1) Both pairs of twins were similar appearance, and also personality traits, and had a strong feeling of companionship for each other. 2) In family relationships, the persons studied were very conscious of the role expectations of elder and younger siblings in the twin pairs. 3) Through depth interview and projective test, A-bomb exposed pairs still showed deep psychological stresses, resulting from the A-bomb disaster. 4) Both among the exposed twins and within the nonexposed control group twin siblings had a close feeling of companionship for each other. However, nonexposed twins could not understand the psychological experience of twins who had been subjected to the atomic disaster. (author)

Sibling rivalry: training effects, emergence of dominance and incomplete control.

Science.gov (United States)

Benhaiem, Sarah; Hofer, Heribert; Kramer-Schadt, Stephanie; Brunner, Edgar; East, Marion L

2012-09-22

Within-brood or -litter dominance provides fitness-related benefits if dominant siblings selfishly skew access to food provided by parents in their favour. Models of facultative siblicide assume that dominants exert complete control over their subordinate sibling's access to food and that control is maintained, irrespective of the subordinate's hunger level. By contrast, a recent functional hypothesis suggests that subordinates should contest access to food when the cost of not doing so is high. Here, we show that within spotted hyena (Crocuta crocuta) twin litters, dominants most effectively skew access to maternal milk in their favour when their aggression prompts a highly submissive response. When hungry, subordinates were less submissive in response to aggression, thereby decreasing lost suckling time and increasing suckling time lost by dominants. In a species where adult females socially dominate adult males, juvenile females were more often dominant than males in mixed-sex litters, and subordinate sisters used more effective counter-tactics against dominant brothers than subordinate brothers against dominant sisters. Our results provide, to our knowledge, the first evidence in a mammal that dominant offspring in twin litters do not exert complete control over their sibling's access to resources (milk), and that sibling dominance relationships are influenced by sibling sex and training effects.

Biologically Costly Altruism Depends on Emotional Closeness among Step but Not Half or Full Sibling

Directory of Open Access Journals (Sweden)

Paola Bressan

2009-01-01

Full Text Available We studied altruistic behaviors of varying biological cost (high, medium, and low among siblings of varying genetic relatedness (full, half, and step. In agreement with inclusive fitness theory, the relative importance of either reliable (such as co-residence or heuristic (such as emotional closeness kinship cues depended crucially on the costs of help. When help did not endanger the altruist's life, thus making reciprocation possible, emotional closeness was the strongest predictor of altruism; perceived physical and psychological similarity to the sibling amplified altruistic behavior via their association with emotional closeness. When help endangered the altruist's life, thus making reciprocation unlikely, the strongest predictor of altruism was the ancestrally valid kinship cue of co-residence duration. Emotional closeness predicted costly altruism only for step siblings; its effects were nonsignificant when siblings were genetically related. Our findings support the idea that emotional closeness promotes costly altruistic behavior by serving as a surrogate kinship cue when more reliable cues are missing.

Sibling genes as environment: Sibling dopamine genotypes and adolescent health support frequency dependent selection.

Science.gov (United States)

Rauscher, Emily; Conley, Dalton; Siegal, Mark L

2015-11-01

While research consistently suggests siblings matter for individual outcomes, it remains unclear why. At the same time, studies of genetic effects on health typically correlate variants of a gene with the average level of behavioral or health measures, ignoring more complicated genetic dynamics. Using National Longitudinal Study of Adolescent Health data, we investigate whether sibling genes moderate individual genetic expression. We compare twin variation in health-related absences and self-rated health by genetic differences at three locations related to dopamine regulation and transport to test sibship-level cross-person gene-gene interactions. Results suggest effects of variation at these genetic locations are moderated by sibling genes. Although the mechanism remains unclear, this evidence is consistent with frequency dependent selection and suggests much genetic research may violate the stable unit treatment value assumption. Copyright © 2015 Elsevier Inc. All rights reserved.

A family affair: brain abnormalities in siblings of patients with schizophrenia

Science.gov (United States)

Hulshoff Pol, Hilleke; Gogtay, Nitin

2013-01-01

Schizophrenia is a severe mental disorder that has a strong genetic basis. Converging evidence suggests that schizophrenia is a progressive neurodevelopmental disorder, with earlier onset cases resulting in more profound brain abnormalities. Siblings of patients with schizophrenia provide an invaluable resource for differentiating between trait and state markers, thus highlighting possible endophenotypes for ongoing research. However, findings from sibling studies have not been systematically put together in a coherent story across the broader age span. We review here the cortical grey matter abnormalities in siblings of patients with schizophrenia from childhood to adulthood, by reviewing sibling studies from both childhood-onset schizophrenia, and the more common adult-onset schizophrenia. When reviewed together, studies suggest that siblings of patients with schizophrenia display significant brain abnormalities that highlight both similarities and differences between the adult and childhood populations, with shared developmental risk patterns, and segregating trajectories. Based on current research it appears that the cortical grey matter abnormalities in siblings are likely to be an age-dependent endophenotype, which normalize by the typical age of onset of schizophrenia unless there has been more genetic or symptom burdening. With increased genetic burdening (e.g. discordant twins of patients) the grey matter abnormalities in (twin) siblings are progressive in adulthood. This synthesis of the literature clarifies the importance of brain plasticity in the pathophysiology of the illness, indicating that probands may lack protective factors critical for healthy development. PMID:23698280

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

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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.

Epigenome-wide DNA methylation analysis in siblings and monozygotic twins discordant for sporadic Parkinson's disease revealed different epigenetic patterns in peripheral blood mononuclear cells.

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Kaut, Oliver; Schmitt, Ina; Tost, Jörg; Busato, Florence; Liu, Yi; Hofmann, Per; Witt, Stephanie H; Rietschel, Marcella; Fröhlich, Holger; Wüllner, Ullrich

2017-01-01

Numerous studies have elucidated the genetics of Parkinson's disease; however, the aetiology of the majority of sporadic cases has not yet been resolved. We hypothesized that epigenetic variations could be associated with PD and evaluated the DNA methylation pattern in PD patients compared to brothers or twins without PD. The methylation of DNA from peripheral blood mononuclear cells of 62 discordant siblings including 24 monozygotic twins was characterized with Illumina DNA Methylation 450K bead arrays and subsequently validated in two independent cohorts: 221 PD vs. 227 healthy individuals (cohort 1) applying Illumina's VeraCode and 472 PD patients vs. 487 controls (cohort 2) using pyrosequencing. We choose a delta beta of >15 % and selected 62 differentially methylated CpGs in 51 genes from the discordant siblings. Among them, three displayed multiple CpGs per gene: microRNA 886 (MIR886, 10 CpGs), phosphodiesterase 4D (PDE4D, 2 CpGs) and tripartite motif-containing 34 (TRIM34, 2 CpGs). PDE4D was confirmed in both cohorts (p value 2.44e-05). In addition, for biomarker construction, we used the penalized logistic regression model, resulting in a signature of eight CpGs with an AUC of 0.77. Our findings suggest that a distinct level of PD susceptibility stems from individual, epigenetic modifications of specific genes. We identified a signature of CpGs in blood cells that could separate control from disease with a reasonable discriminatory power, holding promise for future epigenetically based biomarker development.

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......-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......, 2.0; 95% CI, 1.3 to 3.0), thereby indicating a genetic component. Using biometric models, we estimated the heritability of AF to be 62% (55% to 68%), due to additive genetics. There were no significant differences across sexes. CONCLUSIONS: All the analyses of twin similarities in the present study...

Vanishing twin syndrome among ART singletons and pregnancy outcomes.

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Magnus, Maria C; Ghaderi, Sara; Morken, Nils-Halvdan; Magnus, Per; Bente Romundstad, Liv; Skjærven, Rolv; Wilcox, Allen J; Eldevik Håberg, Siri

2017-11-01

Among babies born by ART, do singleton survivors of a vanishing twin have lower birth weight than other singletons? Vanishing twin syndrome (VTS) was associated with lower birth weight among ART singletons; a sibship analysis indicated that the association was not confounded by maternal characteristics that remain stable between deliveries. Previous studies indicate that ART singletons with VTS have increased risk of adverse pregnancy outcomes, compared with other ART singletons. The potential contribution of unmeasured maternal background characteristics has been unclear. This was a Norwegian population-based registry study, including 17 368 mothers with 20 410 ART singleton deliveries between January 1984 and December 2013. The study population included 17 291 ART singletons without VTS, 638 ART singletons with VTS and 2418 ART singletons with uncertain vanishing twin status. We estimated differences in birth weight and gestational age comparing ART singletons with VTS first to all ART singletons without VTS, and subsequently to their ART siblings without VTS, using random- and fixed-effects linear regression, respectively. The corresponding comparisons for the associations with preterm birth and small for gestational age (SGA) were conducted using random-and fixed-effects logistic regression. The sibling analysis of preterm birth included 587 discordant siblings, while the sibling analysis of SGA included 674 discordant siblings. ART singletons with VTS had lower birth weight when compared to all ART singletons without VTS, with an adjusted mean difference (95% CI) of -116 g (-165, -67). When we compared ART singletons with VTS to their ART singletons sibling without VTS, the adjusted mean difference was -112 g (-209, -15). ART singletons with VTS also had increased risk of being born SGA, with an adjusted odds ratio (OR) (95% CI) of 1.48 (1.07, 2.03) compared to all ART singletons without VTS, and 2.79 (1.12, 6.91) in the sibship analyses. ART singletons with

A population-based Swedish Twin and Sibling Study of cannabis, stimulant and sedative abuse in men.

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

2015-04-01

Prior studies, utilizing interview-based assessments, suggest that most of the genetic risk factors for drug abuse (DA) are non-specific with a minority acting specifically on risk for abuse of particular psychoactive substance classes. We seek to replicate these findings using objective national registry data. We examined abuse of cannabis, stimulants (including cocaine) and sedatives ascertained from national Swedish registers in male-male monozygotic (1720 pairs) and dizygotic twins (1219 pairs) combined with near-age full siblings (76,457 pairs) to provide sufficient power. Modeling was performed using Mx. A common pathway model fitted better than an independent pathway model. The latent liability to DA was highly heritable but also influenced by shared environment. Cannabis, stimulant and sedative abuse all loaded strongly on the common factor. Estimates for the total heritability for the three forms of substance abuse ranged from 64 to 70%. Between 75 and 90% of that genetic risk was non-specific, coming from the common factor with the remainder deriving from substance specific genetic risk factors. By contrast, all of the shared environmental effects, which accounted for 18-20% of the variance in liability, were non-specific. In accord with prior studies based on personal interviews, the large preponderance of genetic risk factors for abuse of specific classes of psychoactive substance are non-specific. These results suggest that genetic variation in the primary sites of action of the psychoactive drugs, which differ widely across most drug classes, play a minor role in human individual differences in risk for DA. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

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

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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.

Siblings' personality traits and types of sibling relationship in childhood

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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.

Preschool outcome of less than 801-gram preterm infants compared with full-term siblings.

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Kilbride, Howard W; Thorstad, Karla; Daily, Donna K

2004-04-01

Extremely low birth weight (ELBW) infants are at greater risk for neurodevelopmental delay than full-term infants. Outcomes may be compromised secondary to abnormal brain development associated with complications of prematurity. Long-term cognitive outcome has also been reported to be significantly influenced by postnatal factors. The objective of this study was to clarify the effects of prematurity separate from environmental factors on growth and neurodevelopmental outcomes by comparing ELBW children with their full-term siblings. The study consisted of 25 ELBW children, a subset selected from a larger population of infants who were siblings. Twenty-three sets of siblings were evaluated at 5 years of age and 2 sets at 3 years of age with standardized medical, social, cognitive, motor, and language testing. Physical and neurodevelopmental outcomes were compared between groups, controlling for gender and socioeconomic status (SES). At follow-up, ELBW children were lighter, were shorter, and had smaller head circumference. The ELBW children had lower Stanford-Binet IQs (85 +/- 12 [mean +/- SD] and 95 +/- 11), with lower Stanford-Binet subtests except short-term memory and quantitative reasoning, lower spelling scores on the Wide Range Achievement Test, and lower Peabody motor quotients (79 +/- 11 and 92 +/- 17). Preschool Language Scale quotients were not different, but other receptive language measures were lower for ELBW children. High SES seemed to modify the impact of preterm status on cognitive and language but not motor scores. The mean IQ for high-SES ELBW children was equivalent to that of the low-SES term siblings. Preschool-age cognitive and language functioning in ELBW children seemed to be affected by both prenatal and birth influences (preterm status) and postnatal influences (SES variables). Motor scores were significantly related to preterm status but not to SES.

Identical Twin Primigravid Sisters -Spontaneous Labour and ...

African Journals Online (AJOL)

We report 2 cases of identical twin sisters, the older sibling getting married 14 months earlier but both got pregnant for their first child at about the same time and were managed by the same Obstetrician and fell into spontaneous labour within a few hours of each other. Both were delivered by emergency caesarean section ...

Self-reported sleep quality, weight status and depression in young adult twins and siblings.

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Sawyer, Alexia; Fisher, Abi; Llewellyn, Clare; Gregory, Alice M

2015-01-01

Research supporting relationships between sleep quality, weight, depression and anxiety has typically examined the relationships separately rather than simultaneously, potentially hampering insights into the characteristics of reported links. This study aimed to fill this gap in the research to provide further insight into the factors associated with sleep. Data from wave 4 of the G1219 cohort were used in cross-sectional analyses. The sample comprised 1392 adult twins and siblings aged 18-27 years. Participants completed a self-report questionnaire which included the Pittsburgh Sleep Quality Index as a measure of sleep quality, the Short Mood and Feelings Questionnaire as a measure of depression symptoms and the Revised Symptoms of Anxiety Scale as a measure of anxiety symptoms. Participants were asked to self-report general health and weight and height so researchers could derive weight status from measures of body mass index. An analysis of covariance including weight status, depression, anxiety and general health as predictors and sleep quality as the outcome revealed main effects of depression (F(3,1163) = 10.93, p relationship between weight and sleep should not be assumed as it is possible that the relationship is at least in part accounted for by depression symptoms or general health. Depression symptoms and general health may also account for the association between sleep quality and anxiety symptoms in young adults.

Aggression Can be Contagious: Longitudinal Associations between Proactive Aggression and Reactive Aggression Among Young Twins

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Dickson, Daniel J.; Richmond, Ashley; 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. PMID:25683448

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

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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

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

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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.

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

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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.

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

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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.

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

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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.

Sibling fairy tales

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Luisa Brunori

2014-06-01

Full Text Available The article offers a reflection on sibling relationships starting from fairy tales. Their archetypical meaning and educative value are particularly analyzed. A selection of fairy tales having sibling relationships as their central theme is discussed.

Genetic and environmental contributions to body mass index: comparative analysis of monozygotic twins, dizygotic twins and same-age unrelated siblings.

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Segal, N L; Feng, R; McGuire, S A; Allison, D B; Miller, S

2009-01-01

Earlier studies have established that a substantial percentage of variance in obesity-related phenotypes is explained by genetic components. However, only one study has used both virtual twins (VTs) and biological twins and was able to simultaneously estimate additive genetic, non-additive genetic, shared environmental and unshared environmental components in body mass index (BMI). Our current goal was to re-estimate four components of variance in BMI, applying a more rigorous model to biological and virtual multiples with additional data. Virtual multiples share the same family environment, offering unique opportunities to estimate common environmental influence on phenotypes that cannot be separated from the non-additive genetic component using only biological multiples. Data included 929 individuals from 164 monozygotic twin pairs, 156 dizygotic twin pairs, five triplet sets, one quadruplet set, 128 VT pairs, two virtual triplet sets and two virtual quadruplet sets. Virtual multiples consist of one biological child (or twins or triplets) plus one same-aged adoptee who are all raised together since infancy. We estimated the additive genetic, non-additive genetic, shared environmental and unshared random components in BMI using a linear mixed model. The analysis was adjusted for age, age(2), age(3), height, height(2), height(3), gender and race. Both non-additive genetic and common environmental contributions were significant in our model (P-valuesrole in BMI and that common environmental factors such as diet or exercise also affect BMI. This conclusion is consistent with our earlier study using a smaller sample and shows the utility of virtual multiples for separating non-additive genetic variance from common environmental variance.

Nineteen and Up study (19Up): understanding pathways to mental health disorders in young Australian twins.

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Couvy-Duchesne, Baptiste; O'Callaghan, Victoria; Parker, Richard; Mills, Natalie; Kirk, Katherine M; Scott, Jan; Vinkhuyzen, Anna; Hermens, Daniel F; Lind, Penelope A; Davenport, Tracey A; Burns, Jane M; Connell, Melissa; Zietsch, Brendan P; Scott, James; Wright, Margaret J; Medland, Sarah E; McGrath, John; Martin, Nicholas G; Hickie, Ian B; Gillespie, Nathan A

2018-03-17

The Nineteen and Up study (19Up) assessed a range of mental health and behavioural problems and associated risk factors in a genetically informative Australian cohort of young adult twins and their non-twin siblings. As such, 19Up enables detailed investigation of genetic and environmental pathways to mental illness and substance misuse within the Brisbane Longitudinal Twin Sample (BLTS). Twins and their non-twin siblings from Queensland, Australia; mostly from European ancestry. Data were collected between 2009 and 2016 on 2773 participants (age range 18-38, 57.8% female, 372 complete monozygotic pairs, 493 dizygotic pairs, 640 non-twin siblings, 403 singleton twins). A structured clinical assessment (Composite International Diagnostic Interview) was used to collect lifetime prevalence of diagnostic statistical manual (4th edition) (DSM-IV) diagnoses of major depressive disorder, (hypo)mania, social anxiety, cannabis use disorder, alcohol use disorder, panic disorder and psychotic symptoms. Here, we further describe the comorbidities and ages of onset for these mental disorders. Notably, two-thirds of the sample reported one or more lifetime mental disorder.In addition, the 19Up study assessed general health, drug use, work activity, education level, personality, migraine/headaches, suicidal thoughts, attention deficit hyperactivity disorder (ADHD) symptomatology, sleep-wake patterns, romantic preferences, friendships, familial environment, stress, anorexia and bulimia as well as baldness, acne, asthma, endometriosis, joint flexibility and internet use.The overlap with previous waves of the BLTS means that 84% of the 19Up participants are genotyped, 36% imaged using multimodal MRI and most have been assessed for psychological symptoms at up to four time points. Furthermore, IQ is available for 57%, parental report of ADHD symptomatology for 100% and electroencephalography for 30%. The 19Up study complements a phenotypically rich, longitudinal collection of

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

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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.

Sources of individual differences in depressive symptoms: analysis of two samples of twins and their families.

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Kendler, K S; Walters, E E; Truett, K R; Heath, A C; Neale, M C; Martin, N G; Eaves, L J

1994-11-01

Self-reported symptoms of depression are commonly used in mental health research to assess current psychiatric state, yet wide variation in these symptoms among individuals has been found in both clinical and epidemiologic populations. The authors sought to understand, from a genetic-epidemiologic perspective, the sources of individual differences in depressive symptoms. Self-reported symptoms of depression were assessed in two samples of twins and their spouses, parents, siblings, and offspring: one sample contained volunteer twins recruited through the American Association of Retired Persons and their relatives (N = 19,203 individuals) and the other contained twins from a population-based twin registry in Virginia and their relatives (N = 11,242 individuals). Model fitting by an iterative, diagonal, weighted least squares method was applied to the 80 different family relationships in the extended twin-family design. Independent analyses of the two samples revealed that the level of depressive symptoms was modestly familial, and familial resemblance could be explained solely by genetic factors and spousal resemblance. The estimated heritability of depressive symptoms was between 30% and 37%. There was no evidence that the liability to depressive symptoms was environmentally transmitted from parents to offspring or was influenced by environmental factors shared either generally among siblings or specifically between twins. With correction for unreliability of measurement, genetic factors accounted for half of the stable variance in depressive symptoms. Depressive symptoms in adulthood partly reflect enduring characteristics of temperament that are substantially influenced by hereditary factors but little, or not at all, by shared environmental experiences in the family of origin.

The etiology of social aggression: a nuclear twin family study.

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Slawinski, Brooke L; Klump, Kelly L; Burt, S Alexandra

2018-04-02

Social aggression is a form of antisocial behavior in which social relationships and social status are used to damage reputations and inflict emotional harm on others. Despite extensive research examining the prevalence and consequences of social aggression, only a few studies have examined its genetic-environmental etiology, with markedly inconsistent results. We estimated the etiology of social aggression using the nuclear twin family (NTF) model. Maternal-report, paternal-report, and teacher-report data were collected for twin social aggression (N = 1030 pairs). We also examined the data using the classical twin (CT) model to evaluate whether its strict assumptions may have biased previous heritability estimates. The best-fitting NTF model for all informants was the ASFE model, indicating that additive genetic, sibling environmental, familial environmental, and non-shared environmental influences significantly contribute to the etiology of social aggression in middle childhood. However, the best-fitting CT model varied across informants, ranging from AE and ACE to CE. Specific heritability estimates for both NTF and CT models also varied across informants such that teacher reports indicated greater genetic influences and father reports indicated greater shared environmental influences. Although the specific NTF parameter estimates varied across informants, social aggression generally emerged as largely additive genetic (A = 0.15-0.77) and sibling environmental (S = 0.42-0.72) in origin. Such findings not only highlight an important role for individual genetic risk in the etiology of social aggression, but also raise important questions regarding the role of the environment.

Family environment, not heredity, accounts for family resemblances in food preferences and attitudes: a twin study.

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Rozin, P; Millman, L

1987-04-01

Monozygotic and same-sex dizygotic twin pairs reported on their food preferences, the variety of foods of the same general category (e.g. types of soup) in their diet, and their concern about contact of their food with disgusting or other unacceptable substances (contamination sensitivity). Although there was substantial resemblance between siblings for many of these items, there was no clear evidence for a heritable component on any item. The only case for which there was an interpretable and significantly greater resemblance among monozygotic than among dizygotic twins (out of 23 questions) was preferred degree of hotness resulting from chili pepper in foods. These results confirm the prediction that in omnivorous animals, such as humans, genetic predispositions will be minimal with respect to food. The modest sibling resemblances on a number of measures are primarily attributable to a shared environment.

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.

Heritability and GWAS Analyses of Acne in Australian Adolescent Twins.

Science.gov (United States)

Mina-Vargas, Angela; Colodro-Conde, Lucía; Grasby, Katrina; Zhu, Gu; Gordon, Scott; Medland, Sarah E; Martin, Nicholas G

2017-12-01

Acne vulgaris is a skin disease with a multifactorial and complex pathology. While several twin studies have estimated that acne has a heritability of up to 80%, the genomic elements responsible for the origin and pathology of acne are still undiscovered. Here we performed a twin-based structural equation model, using available data on acne severity for an Australian sample of 4,491 twins and their siblings aged from 10 to 24. This study extends by a factor of 3 an earlier analysis of the genetic factors of acne. Acne severity was rated by nurses on a 4-point scale (1 = absent to 4 = severe) on up to three body sites (face, back, chest) and on up to three occasions (age 12, 14, and 16). The phenotype that we analyzed was the most severe rating at any site or age. The polychoric correlation for monozygotic twins was higher (r MZ = 0.86, 95% CI [0.81, 0.90]) than for dizygotic twins (r DZ = 0.42, 95% CI [0.35, 0.47]). A model that includes additive genetic effects and unique environmental effects was the most parsimonious model to explain the genetic variance of acne severity, and the estimated heritability was 0.85 (95% CI [0.82, 0.87]). We then conducted a genome-wide analysis including an additional 271 siblings - for a total of 4,762 individuals. A genome-wide association study (GWAS) scan did not detect loci associated with the severity of acne at the threshold of 5E-08 but suggestive association was found for three SNPs: rs10515088 locus 5q13.1 (p = 3.9E-07), rs12738078 locus 1p35.5 (p = 6.7E-07), and rs117943429 locus 18q21.2 (p = 9.1E-07). The 5q13.1 locus is close to PIK3R1, a gene that has a potential regulatory effect on sebocyte differentiation.

Genetic and environmental influences on the familial transmission of externalizing disorders in adoptive and twin offspring.

Science.gov (United States)

Hicks, Brian M; Foster, Katherine T; Iacono, William G; McGue, Matt

2013-10-01

Twin-family studies have shown that parent-child resemblance on substance use disorders and antisocial behavior can be accounted for by the transmission of a general liability to a spectrum of externalizing disorders. Most studies, however, include only biological parents and offspring, which confound genetic and environmental transmission effects. To examine the familial transmission of externalizing disorders among both adoptive (genetically unrelated) and biological relatives to better distinguish genetic and environmental mechanisms of transmission. Family study design wherein each family included the mother, father, and 2 offspring, including monozygotic twin, dizygotic twin, nontwin biological, and adoptive offspring. Structural equation modeling was used to estimate familial transmission effects and their genetic and environmental influences. Participants were recruited from the community and assessed at a university laboratory. A total of 1590 families with biological offspring and 409 families with adoptive offspring. Offspring participants were young adults (mean age, 26.2 years). Symptom counts of conduct disorder, adult antisocial behavior, and alcohol, nicotine, and drug dependence. RESULTS There was a medium effect for the transmission of the general externalizing liability for biological parents (r = 0.27-0.30) but not for adoptive parents (r = 0.03-0.07). In contrast, adoptive siblings exhibited significant similarity on the general externalizing liability (r = 0.21). Biometric analyses revealed that the general externalizing liability was highly heritable (a2 = 0.61) but also exhibited significant shared environmental influences (c2 = 0.20). Parent-child resemblance for substance use disorders and antisocial behavior is primarily due to the genetic transmission of a general liability to a spectrum of externalizing disorders. Including adoptive siblings revealed a greater role of shared environmental influences on the general externalizing liability

The association of current smoking behavior with the smoking behavior of parents, siblings, friends and spouses

NARCIS (Netherlands)

Vink, J.M.; Willemsen, G.; Boomsma, D.I.

2003-01-01

Aims: To examine the association of current smoking behavior of adolescents and young adults with the smoking behavior of their parents, siblings, friends and spouses. Design: Using survey data from a large twin-family sample, the association between the smoking behavior of participants and that of

Twin-twin transfusion syndrome - diagnosis and prognosis

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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

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…

Musical Interests and Talent: Twin Jazz Musicians and Twin Studies/Twin Research: Loss of a Preterm Multiple; Conjoined Twin Conception; Depression in Fathers of Twins; Twin-to-Twin Transfusion Syndrome/Twin News: High-Achieving Twins; Twin Children of a Tennis Star; Conjoined Twin Separation; Twin Delivery to a Giant Panda.

Science.gov (United States)

Segal, Nancy L

2017-12-01

Findings from twin studies of musical interests and talent are reviewed as a backdrop to the lives and careers of twin jazz musicians, Peter and Will Anderson. The Anderson twins exemplify many aspects of twin research, namely their matched musical abilities, shared musical interests, and common career. This overview is followed by reviews of studies and case reports of bereavement in families who have lost a preterm multiple birth infant, the conception of conjoined twins following in vitro fertilization (IVF), depression in fathers of twins, and twin-to-twin transfusion incidence in monochorionic-diamniotic IVF twin pairs. Twins highlighted in the media include high-achieving identical female twins with nearly identical academic standing, tennis star Roger Federer's two sets of identical twin children, surgical separation of craniopagus conjoined twins, and the rare delivery of twins to a 23-year-old giant panda.

Therapeutic modalities of twin to twin transfusion syndrome

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Šulović N.

2015-01-01

Full Text Available Twin to twin transfusion syndrome (TTTTS accounts for approximately 10% of monochorionic twin pregnancies and, if left untreated, is associated with high morbidity and mortality rate. A net transfusion of blood flow from one fetus (donor twin to the other (recipient twin via placental vascular anastomoses has been supposed as the major etiology of TTTTS. The donor twin becomes hypovolemic and oliguria, oligohydramnios, and a variable degree of growth restriction develop, whereas the recipient twin manifests polyuria, polyhydramnios, and hydrops in response to hypervolemia. TTTTS can be treated by either serial amniocentesis or selective fetoscopic laser coagulation of the communicating vessels. The rationale for removal of large volumes of amniotic fluid is to prevent preterm delivery secondary to polyhydramnios and to improve fetal circulation by reducing pressure on the chorionic plate. On the other hand, the goal of laser therapy is to occlude vascular anastomoses, thereby interrupting intertwin blood exchange. Although laser treatment is associated with increased survival rate and reduced neurologic complications, compared with amnioreduction, it requires highly specialized centers, whereas serial amniocentesis has the advantage of being performed worldwide. Therefore, the optimal treatment for pregnancies complicated with TTTTS is still controversial.

Differences in the Expression of TLR-2, NOD2, and NF-κB in Placenta Between Twins.

Science.gov (United States)

Szylberg, Łukasz; Bodnar, Magdalena; Lebioda, Anna; Krepska, Patrycja; Kowalewski, Adam; Bręborowicz, Grzegorz; Marszałek, Andrzej

2018-05-23

Dizygotic twins share the same type of genetic relationship as non-twin siblings. Whereas monozygotic (MZ) twins are considered to have identical genetic material, they still differ. There is a number of reasons for early MZ twin discordance, including differences in the in utero environment, stochasticity, genetic mosaicism, and epigenetic factors. During gestation, the efficient innate immune system is of utmost importance. Our study was based on immunohistochemical evaluation of the differences in innate immune protein expression (TLR-2, NOD2, and NF-κB) in the 95 placentas between twins. Our study revealed statistical significant differences between diamniotic-dichorionic and monoamniotic-dichorionic twins. Monoamniotic-monochorionic twins exhibited no significant differences in protein expressions. To identify epigenetic factors causing the differences between twins, we made a series of comparisons with clinical data. The study revealed more cases with infections, miscarriages, in vitro fertilization, and premature rupture of membranes within the group with higher differences level of NF-κB, NOD2 and TLR-2 between twins. In case of twin-to-twin transfusion syndrome, there were no significant differences in innate immune protein expressions between twins. These results show that dissimilar genetic material and separate in utero environment promote discordance in innate immune protein expressions between twins. Moreover, additional blood flow between twins may be favorable in life-threatening conditions ensuring similar microenvironment.

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 in De...

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

Sibling differentiation: sibling and parent relationship trajectories in adolescence.

Science.gov (United States)

Feinberg, Mark E; McHale, Susan M; Crouter, Ann C; Cumsille, Patricio

2003-01-01

Studied here were the links between sibling differences in trajectories of change in the qualities of parent-child relationships and the qualities of sibling relationships across a 2-year period in adolescence. Participants were first- and second-born siblings (M age = 14.94 years for firstborns and M age = 12.46 years for secondborns) from 185 predominantly White, working and middle-class families. In home interviews, siblings reported on their dyadic family relationships. For reports of parent-child warmth but not parent-child conflict, results were consistent with sibling differentiation theory: Increasing differences between siblings over time in parent-child warmth were linked to trajectories of increasing warmth and decreasing conflict in the sibling relationship as reported by firstborns, and increasing warmth in the sibling relationship as reported by secondborns. The findings support the view that sibling differentiation may be a strategy for managing sibling conflict and rivalry.

Pretense of parentage by siblings in immigration: Polesky's paradox reconsidered.

Science.gov (United States)

Wenk, Robert E; Shao, Alison

2014-02-01

Older and younger siblings occasionally attempt to impersonate parent and child to expedite immigration under US family-based visa policies. The rate with which full siblings escape detection by current relationship tests is unknown. Retrospective study of full-sibling immigrant pairs was undertaken to determine the proportion that show insufficient genetic evidence to exclude parentage. Sibship and parentage indices (SI and PI) were compared/case in unexcluded sibling cases and true parent-child cases. Alleles shared per short-tandem-repeat locus were compared in sibling and parent-child pairs. The proportion of successful parentage fraud by siblings was estimated from the parentage exclusion rate among immigrants and the proportion of sibships without genetic inconsistencies (GIs). When 11 to 25 independent loci were tested per two-sibling case to verify or refute parentage, tests failed to demonstrate any GI in 9% and PI was greater than SI in seven of 10 of these cases. Another 29% of full-sibling pairs demonstrated insufficient evidence (fewer than two GIs) to exclude parentage. Thus, 0.4% of sibling pairs could falsely claim a parent-child relationship and show no GIs. Another 1.4% could make that false claim and not present sufficient evidence to be excluded. At present, with no evidence of parentage exclusion in a full-sibling pair, the relative magnitudes of PI and SI are misleading relationship indicators because too few loci are examined and rates of sharing one and two alleles/locus vary greatly in parentage and sibling pairs. Only evidence of exclusion ascertains false parentage claims by siblings. Nevertheless, the expected rate of successful fraud is quite low. © 2013 American Association of Blood Banks.

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

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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.

Relationships between adult siblings

Directory of Open Access Journals (Sweden)

Nives Ličen

2006-12-01

Full Text Available The author presents learning in private relationships between adult siblings. A concept of a family as microculture is presented, which is a source for giving explanation for random and opportunist learning. The author has used a biographic method of research. Using thematic life stories, which she has familiarized herself with through thematicalbiographical interviews is a basis to establish which events have served for learning in relationships between siblings.

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

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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

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

International Nuclear Information System (INIS)

Mannerkoski, M.; Heiskala, H.; Aaberg, L.; Raininko, R.; Sarna, S.; Wirtavuori, K.; Autti, T.

2009-01-01

Background: Several factors are involved in determining a child's need for special education (SE). 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-time SE

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.

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.

Cross-Cultural Comparison of Genetic and Cultural Transmission of Smoking Initiation Using an Extended Twin Kinship Model.

Science.gov (United States)

Maes, Hermine H; Morley, Kate; Neale, Michael C; Kendler, Kenneth S; Heath, Andrew C; Eaves, Lindon J; Martin, Nicholas G

2018-06-01

Considerable evidence from twin and adoption studies indicates that genetic and shared environmental factors play a role in the initiation of smoking behavior. Although twin and adoption designs are powerful to detect genetic and environmental influences, they do not provide information on the processes of assortative mating and parent-offspring transmission and their contribution to the variability explained by genetic and/or environmental factors. We examined the role of genetic and environmental factors in individual differences for smoking initiation (SI) using an extended kinship design. This design allows the simultaneous testing of additive and non-additive genetic, shared and individual-specific environmental factors, as well as sex differences in the expression of genes and environment in the presence of assortative mating and combined genetic and cultural transmission, while also estimating the regression of the prevalence of SI on age. A dichotomous lifetime 'ever' smoking measure was obtained from twins and relatives in the 'Virginia 30,000' sample and the 'Australian 25,000'. Results demonstrate that both genetic and environmental factors play a significant role in the liability to SI. Major influences on individual differences appeared to be additive genetic and unique environmental effects, with smaller contributions from assortative mating, shared sibling environment, twin environment, cultural transmission, and resulting genotype-environment covariance. Age regression of the prevalence of SI was significant. The finding of negative cultural transmission without dominance led us to investigate more closely two possible mechanisms for the lower parent-offspring correlations compared to the sibling and DZ twin correlations in subsets of the data: (1) age × gene interaction, and (2) social homogamy. Neither of the mechanism provided a significantly better explanation of the data. This study showed significant heritability, partly due to assortment

A Twin-Sibling Study on the Relationship Between Exercise Attitudes and Exercise Behavior

NARCIS (Netherlands)

Huppertz, C.; Bartels, M.; Jansen, I.E.; Boomsma, D.I.; Willemsen, G.; de Moor, M.H.M.; de Geus, E.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

Caught Between Cultures: Hmong Parents in America’s Sibling Society

Directory of Open Access Journals (Sweden)

Tamara L. Kaiser

2005-01-01

Full Text Available Based on a qualitative study of the Hmong Community in the Twin Cities of Minneapolis and St. Paul, this paper addresses the conflict between the traditionally hierarchical and patriarchal Hmong culture and those aspects of American culture that elevate freedom and equality over, not only patriarchy, but over hierarchy in general. Although this conflict has forced the Hmong community to change in some positive ways, it also creates great challenges for parents and their children. Distorted values of “freedom” and “equality,” promoted by much of American culture, compromise the ability of many Hmong to be effective parents. A comparison of traditional Hmong parenting with what author Robert Bly calls America’s “sibling society” demonstrates that both Hmong and mainstream families and society are hurt by a general rejection of authority and would greatly benefit from recognizing the value of hierarchy based on experience, genuine accomplishment and wisdom.

Sibling popularity: A moderator of sibling influence for adolescent substance use.

Science.gov (United States)

Wallace, Lacey N

Sibling substance use is a known correlate of adolescent substance use. Yet, not all siblings are equally influential. Sibling influence has been found to vary by age gap, sex, and birth order. Little research, however, has investigated whether siblings' peer context is also a source of variation. The present study tested whether more popular siblings were more influential for adolescent use of cigarettes, alcohol, and marijuana. Data were obtained from sibling pairs in the National Longitudinal Study of Adolescent Health. Findings indicate that older siblings have more influence on younger sibling marijuana use when they have more friends. These findings contribute to prior work examining which siblings are more influential and highlight the need to consider siblings as part of a greater peer context.

Relationship between siblings and psychological adjustment in adolescents:

Directory of Open Access Journals (Sweden)

Karen Ripoll

2009-10-01

Full Text Available This study evaluated the effect of parent-child relationship quality (acceptance and differential treatment over dimensions of the quality of sibling relationships (warmth and conflict and psychological adjustment in 69 adolescent sibling dyads. The effects of parent-child relationships were evaluated both at the individual and dyadic levels. In older siblings, the father-child relationship had a significant effect on both their perception of warmth in the sibling relationship and psychological adjustment. In younger siblings, there was a significant dyadic effect of the older sibling’s perceived acceptance by mother on their perception of warmth in the sibling relationship. Results are analyzed based on the literature and questions for future research are proposed.

Cancer risk in siblings of children with congenital malformations

DEFF Research Database (Denmark)

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

2016-01-01

PURPOSE: Cancer and birth defects cluster in families more often than expected by chance, but the reasons are neither well known nor well studied. METHODS: From singletons born alive in Denmark between 1 January 1977 and 31 December 2007, we identified children who had no congenital malformations...... 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...

The 16th International Twin Congress: Highlights from Madrid/Twin Research: Twin Study of Partner Aggression; ABO Incompatibility in Dizygotic Twins; Growth Discordance in a Monoamniotic Twin Pair; Quick Note on Twin Implantation/In the Media: Long-Lost Twins Found; NASA Twin Experiment; Twin Brothers and the Las Vegas Attack; Retired Twin Airline Pilots; Twin Film Clips.

Science.gov (United States)

Segal, Nancy L

2018-02-01

Highlights from the 16th International Twin Congress, held in Madrid, Spain from November 16-18, 2017, are presented. The Twin Congress, formerly held every three years, now takes place biennially with a single-day meeting organized during the off years. This meeting is the largest gathering of scientific twin researchers, medical personnel, and representatives of multiple birth organizations in the world. This overview is followed by reviews of recent twin research and commentary concerning partner aggression, ABO incompatibility in dizygotic twins, growth discordance in a monoamniotic twin pair and twin implantation. The article closes with summaries of timely topics in the media, namely a father's finding of his long-lost twin children, early results from the NASA twin experiment, twin brothers at the center of the October 2017 Las Vegas attack, retired twin airline pilots, and clips from recent films with twin-based themes.

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.

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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.

Sibling Relationships and Adolescents' Mental Health: The Interrelationship of Structure and Quality

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Yuan, Anastasia S. Vogt

2009-01-01

Although sibling structure influences some aspects of adolescents' well-being, including deviance and educational achievement, little research has explored the association between sibling structure and adolescents' mental health. This study explores how sibling structure (the number of siblings, full versus step- or half-siblings, the relative age…

Heritability of tic disorders: a twin-family study.

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Zilhão, N R; Olthof, M C; Smit, D J A; Cath, D C; Ligthart, L; Mathews, C A; Delucchi, K; Boomsma, D I; Dolan, C V

2017-04-01

Genetic-epidemiological studies that estimate the contributions of genetic factors to variation in tic symptoms are scarce. We estimated the extent to which genetic and environmental influences contribute to tics, employing various phenotypic definitions ranging between mild and severe symptomatology, in a large population-based adult twin-family sample. In an extended twin-family design, we analysed lifetime tic data reported by adult mono- and dizygotic twins (n = 8323) and their family members (n = 7164; parents and siblings) from 7311 families in the Netherlands Twin Register. We measured tics by the abbreviated version of the Schedule for Tourette and Other Behavioral Syndromes. Heritability was estimated by genetic structural equation modeling for four tic disorder definitions: three dichotomous and one trichotomous phenotype, characterized by increasingly strictly defined criteria. Prevalence rates of the different tic disorders in our sample varied between 0.3 and 4.5% depending on tic disorder definition. Tic frequencies decreased with increasing age. Heritability estimates varied between 0.25 and 0.37, depending on phenotypic definitions. None of the phenotypes showed evidence of assortative mating, effects of shared environment or non-additive genetic effects. Heritabilities of mild and severe tic phenotypes were estimated to be moderate. Overlapping confidence intervals of the heritability estimates suggest overlapping genetic liabilities between the various tic phenotypes. The most lenient phenotype (defined only by tic characteristics, excluding criteria B, C and D of DSM-IV) rendered sufficiently reliable heritability estimates. These findings have implications in phenotypic definitions for future genetic studies.

Korean sibling caregivers of individuals diagnosed with schizophrenia

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Mijung Park

2017-12-01

Full Text Available Siblings of individuals diagnosed with schizophrenia are an important source of family caregiving. Unfortunately, limited information is available about sibling caregivers because existing studies have focused on other family relationships such as parents, spouses, and children. To fill the knowledge gap, the purpose of this study is to describe Korean sibling caregivers’ experience with individuals diagnosed with schizophrenia. Guided by Colaizzi’s descriptive phenomenological methodology, we conducted in-depth, semi-structured, face-to-face interviews with eight individuals who have a sibling (1 diagnosed with schizophrenia and (2 hospitalized in an inpatient psychiatric unit. We discerned six key themes: sorrow, burnout, shame, different perspectives in life, acceptance, and responsibility. We categorized these themes into three groups: suffering, hope, and responsibility and obligation. Sibling caregivers of individuals with schizophrenia experience a mixture of several emotions. Participants loved their brother or sister with schizophrenia, but at the same time they felt shame and fear. While they were burdened by the responsibilities of caregiving, they remained loyal to their sibling with schizophrenia, continuing to help their siblings reach their full potential. Although participants were confused about the symptoms of schizophrenia, they were committed to learning more about the illness. Because we conducted the current study in Korea, the findings of this study may be unique to Korea culture. Further studies are needed to compare and contrast nuanced differences in sibling caregivers’ experience among different cultural groups.

Bullying among siblings.

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Wolke, Dieter; Skew, Alexandra J

2012-01-01

Parents are often concerned about repeated conflicts between their daughters and sons. However, there is little empirical research of sibling bullying. To conduct a review of existing studies of sibling bullying. Are there any associations between sibling bullying and peer bullying at school? What are the consequences of sibling bullying? Is there good justification why sibling bullying has been so neglected in research? Studies of sibling relationships were reviewed. Four quantitative studies were identified that report on both sibling and peer bullying. Sibling bullying is frequent with up to 50% involved in sibling bullying every month and between 16% and 20% involved in bullying several times a week. Experience of sibling bullying increases the risk of involvement in bullying in school. Both, bullying between siblings and school bullying make unique contributions to explaining behavioral and emotional problems. There is a clear dose-effect relationship of involvement of bullying at home and at school and behavioral or emotional problems. Those involved in both have up to 14 times increased odds of behavioral or emotional problems compared to those involved in only one context or not at all. The empirical evidence is limited and studies are mostly cross-sectional studies. Nevertheless, the review suggests that for those victimized at home and at school behavioral and emotional problems are highly increased. Sibling relationships appear to be a training ground with implications for individual well-being. Strengthening families and parenting skills and increasing sibling support is likely to reduce bullying and increase well-being.

Binomial outcomes in dataset with some clusters of size two: can the dependence of twins be accounted for? A simulation study comparing the reliability of statistical methods based on a dataset of preterm infants

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Odile Sauzet

2017-07-01

Full Text Available Abstract Background The analysis of perinatal outcomes often involves datasets with some multiple births. These are datasets mostly formed of independent observations and a limited number of clusters of size two (twins and maybe of size three or more. This non-independence needs to be accounted for in the statistical analysis. Using simulated data based on a dataset of preterm infants we have previously investigated the performance of several approaches to the analysis of continuous outcomes in the presence of some clusters of size two. Mixed models have been developed for binomial outcomes but very little is known about their reliability when only a limited number of small clusters are present. Methods Using simulated data based on a dataset of preterm infants we investigated the performance of several approaches to the analysis of binomial outcomes in the presence of some clusters of size two. Logistic models, several methods of estimation for the logistic random intercept models and generalised estimating equations were compared. Results The presence of even a small percentage of twins means that a logistic regression model will underestimate all parameters but a logistic random intercept model fails to estimate the correlation between siblings if the percentage of twins is too small and will provide similar estimates to logistic regression. The method which seems to provide the best balance between estimation of the standard error and the parameter for any percentage of twins is the generalised estimating equations. Conclusions This study has shown that the number of covariates or the level two variance do not necessarily affect the performance of the various methods used to analyse datasets containing twins but when the percentage of small clusters is too small, mixed models cannot capture the dependence between siblings.

Psychosis among "healthy" siblings of schizophrenia patients

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Partonen Timo

2006-01-01

Full Text Available Abstract Background Schizophrenia aggregates in families and accurate diagnoses are essential for genetic studies of schizophrenia. In this study, we investigated whether siblings of patients with schizophrenia can be identified as free of any psychotic disorder using only register information. We also analyzed the emergence of psychotic disorders among siblings of patients with schizophrenia during seven to eleven years of follow-up. Methods A genetically homogenous population isolate in north-eastern Finland having 365 families with 446 patients with a diagnosis of schizophrenia was initially identified in 1991 using four nationwide registers. Between 1998 and 2002, 124 patients and 183 siblings in 110 families were contacted and interviewed using SCID-I, SCID-II and SANS. We also compared the frequency of mental disorders between siblings and a random population comparison group sample. Results Thirty (16% siblings received a diagnosis of psychotic disorder in the interview. 14 siblings had had psychotic symptoms already before 1991, while 16 developed psychotic symptoms during the follow-up. Over half of the siblings (n = 99, 54% had a lifetime diagnosis of any mental disorder in the interview. Conclusion Register information cannot be used to exclude psychotic disorders among siblings of patients with schizophrenia. The high rate of emergence of new psychotic disorders among initially healthy siblings should be taken into account in genetic analysis.

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

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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.

[Application of multiple polymorphism genetic markers in determination of half sibling sharing a same mother].

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Que, Ting-zhi; Zhao, Shu-min; Li, Cheng-tao

2010-08-01

Determination strategies for half sibling sharing a same mother were investigated through the detection of autosomal and X-chromosomal STR (X-STR) loci and polymorphisms on hypervariable (HV) region of mitochondrial DNA (mtDNA). Genomic DNA were extracted from blood stain samples of the 3 full siblings and one dubious half sibling sharing the same mother with them. Fifteen autosomal STR loci were genotyped by Sinofiler kit, and 19 X-STR loci were genotyped by Mentype Argus X-8 kit and 16 plex in-house system. Polymorphisms of mtDNA HV-I and HV-II were also detected with sequencing technology. Full sibling relationship between the dubious half sibling and each of the 3 full siblings were excluded based on the results of autosomal STR genotyping and calculation of full sibling index (FSI) and half sibling index (HIS). Results of sequencing for mtDNA HV-I and HV-II showed that all of the 4 samples came from a same maternal line. X-STR genotyping results determined that the dubious half sibling shared a same mother with the 3 full siblings. It is reliable to combine three different genotyping technologies including autosomal STR, X-STR and sequencing of mtDNA HV-I and HV-II for determination of half sibling sharing a same mother.

An initial look at sibling reports on children's behavior: comparisons with children's self-reports and relations with siblings' self-reports and sibling relationships.

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Epkins, C C; Dedmon, A M

1999-10-01

The authors examined siblings' reports of children's depression, anxiety, and aggression, and their reports of the sibling relationship, and compared them with children's self-reports. In two samples, including 169 sibling pairs (age M = 9.98 years, SD = 1.51), no significant differences emerged in the levels of depression and anxiety found in siblings' reports of children's behavior and children's self-reports, although siblings reported children to have significantly higher levels of aggression than the children self-reported. Age, the difference in ages between siblings, sex, and sibling sex were not related to siblings' reports of children's behavior. The relations between children's and siblings' reports of children's behavior were significant, yet moderate (average r = .22). Both siblings' self-reports of internalizing behavior and their perceptions of aspects of the sibling relationship (affection, rivalry, hostility, and satisfaction with the sibling relationship) explained significant, and unique, variance in siblings' reports of children's internalizing behavior. The findings for aggressive behavior were similar, although siblings' perceptions of affection in the sibling relationship were not significantly related to their reports of children's aggression. The potential uses and benefits of sibling reports of children's behavior, and sibling and family relationships, are discussed.

Is that me or my twin? Lack of self-face recognition advantage in identical twins.

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Matteo Martini

Full Text Available Despite the increasing interest in twin studies and the stunning amount of research on face recognition, the ability of adult identical twins to discriminate their own faces from those of their co-twins has been scarcely investigated. One's own face is the most distinctive feature of the bodily self, and people typically show a clear advantage in recognizing their own face even more than other very familiar identities. Given the very high level of resemblance of their faces, monozygotic twins represent a unique model for exploring self-face processing. Herein we examined the ability of monozygotic twins to distinguish their own face from the face of their co-twin and of a highly familiar individual. Results show that twins equally recognize their own face and their twin's face. This lack of self-face advantage was negatively predicted by how much they felt physically similar to their co-twin and by their anxious or avoidant attachment style. We speculate that in monozygotic twins, the visual representation of the self-face overlaps with that of the co-twin. Thus, to distinguish the self from the co-twin, monozygotic twins have to rely much more than control participants on the multisensory integration processes upon which the sense of bodily self is based. Moreover, in keeping with the notion that attachment style influences perception of self and significant others, we propose that the observed self/co-twin confusion may depend upon insecure attachment.

The USC Adult Twin Cohorts: International Twin Study and California Twin Program.

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Cozen, Wendy; Hwang, Amie E; Cockburn, Myles G; Hamilton, Ann S; Zadnick, John; Mack, Thomas M

2013-02-01

The study of twin subjects permits the documentation of crude heritability and may promote the identification of specific causal alleles. We believe that at the current time, the chief research advantage of twins as subjects, especially monozygotic twins, is that the commonality of their genetic and cultural identity simplifies the interpretation of biological associations. In order to study genetic and environmental determinants of cancer and chronic diseases, we developed two twin registries, maintained at the University of Southern California: The International Twin Study (ITS) and the California Twin Program (CTP). The ITS is a volunteer registry of twins with cancer and chronic disease consisting of 17,245 twin pairs affected by cancer and chronic disease, respectively, ascertained by advertising in periodicals from 1980-1991. The CTP is a population-based registry of California-born twin pairs ascertained by linking the California birth records to the State Department of Motor Vehicles. Over 51,000 individual California twins representing 36,965 pairs completed and returned 16-page questionnaires. Cancer diagnoses in the California twins are updated by regular linkage to the California Cancer Registry. Over 5,000 cancer patients are represented in the CTP. Twins from both registries have participated extensively in studies of breast cancer, melanoma, lymphoma, multiple sclerosis, systemic lupus erythematosus, diabetes mellitus type 1, mammographic density, smoking, and other traits and conditions.

Siblings of children with life-limiting conditions: psychological adjustment and sibling relationships.

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Fullerton, J M; Totsika, V; Hain, R; Hastings, R P

2017-05-01

This study explored psychological adjustment and sibling relationships of siblings of children with life-limiting conditions (LLCs), expanding on previous research by defining LLCs using a systematic classification of these conditions. Thirty-nine siblings participated, aged 3-16 years. Parents completed measures of siblings' emotional and behavioural difficulties, quality of life, sibling relationships and impact on families and siblings. Sibling and family adjustment and relationships were compared with population norms, where available, and to a matched comparison group of siblings of children with autistic spectrum disorder (ASD), as a comparable 'high risk' group. LLC siblings presented significantly higher levels of emotional and behavioural difficulties, and lower quality of life than population norms. Their difficulties were at levels comparable to siblings of children with ASD. A wider impact on the family was confirmed. Family socio-economic position, time since diagnosis, employment and accessing hospice care were factors associated with better psychological adjustment. Using a systematic classification of LLCs, the study supported earlier findings of increased levels of psychological difficulties in siblings of children with a LLC. The evidence is (i) highlighting the need to provide support to these siblings and their families, and (ii) that intervention approaches could be drawn from the ASD field. © 2016 John Wiley & Sons Ltd.

Siblings exposed to intimate partner violence: linking sibling relationship quality & child adjustment problems.

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Piotrowski, Caroline C; Tailor, Ketan; Cormier, Damien C

2014-01-01

Although the majority of families that experience intimate partner violence (IPV) have more than one child, most research to date has focused upon a single child within these families. A significant body of research has indicated siblings play an important role in children's adjustment and well-being. To address this gap, the three main goals of the present study were to compare the adjustment of older and younger siblings exposed to IPV, to describe and compare the quality of these sibling relationships from multiple perspectives, and to investigate how sibling adjustment and relationship quality influence children's adjustment. Forty-seven sibling pairs and their mothers were recruited from the community. Mothers self-reported on their violent experiences using the Conflict Tactics Scale, and also estimated the length of time their children were exposed to IPV. Mothers and children completed assessments of child adjustment and the quality of sibling relationships. Observers also assessed the quality of sibling interaction. Results indicated that adjustment between siblings was highly inter-related. On average, mothers reported sibling relationships as less positive but also as less hostile than did siblings themselves. Higher levels of sibling hostility, lower levels of sibling warmth and higher levels of disengagement each significantly predicted child adjustment; however, these effects were predicated upon the adjustment of the other sibling. The sibling relationships of children exposed to IPV made a difference in their individual adjustment, and their adjustment issues influenced how they feel about and interacted with their sibling. Sibling hostility played a stronger role in adjustment issues than sibling warmth. The nature of sibling influences and the direction of future research were discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Sibling Incest.

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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,…

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

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Wade, Mark; Prime, Heather; Madigan, Sheri

2015-01-01

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.

Sibling solidarity in a polygamous community in the USA. unpacking inclusive fitness.

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Jankowiak; Diderich

2000-03-01

This pilot study explores the degree of solidarity felt between full and half siblings who are raised in a Mormon Fundamentalist polygamous community. The community under study is unique in that, at the level of official culture, it actively promotes full and half sibling solidarity through an ethos that strives to downplay genetic differences in favor of a harmonious family living together in one household. This community is an ideal cultural setting in which to examine the suitability of inclusive fitness theory for understanding the factors that promote family cohesion, sibling solidarity, and rivalry. Our main question becomes: is the degree of sibling solidarity a manifestation of genetic closeness or a natural byproduct of emotional closeness that arises from being raised together? We found evidence for more solidarity between full siblings than between half siblings. Our data suggest that, despite the force of religious ideals, and notwithstanding the continued close physical proximity of half siblings in the polygamous family, there is a pronounced clustering of feeling and affection in the polygamous family that is consistent with inclusive fitness theory.

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.

Measuring adolescents’ exposure to victimization: The Environmental Risk (E-Risk) Longitudinal Twin Study

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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

Siblings and children's time use in the United States

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Rachel Dunifon

2017-11-01

Full Text Available Background: Eighty-two percent of children under age 18 live with at least one sibling, and the sibling relationship is typically the longest-lasting family relationship in an individual's life. Nevertheless, siblings remain understudied in the family demography literature. Objective: We ask how having a sibling structures children's time spent with others and in specific activities, and how children's time and activities with siblings vary by social class, gender, and age. Methods: We use time diary data from the US Panel Study of Income Dynamics' Child Development Supplement (PSID-CDS, comparing the time use of children with and without siblings and presenting regression-adjusted descriptive statistics on patterns among those with siblings. Results: Children with siblings spend about half of their discretionary time engaged with siblings. They spend less time alone with parents and more time in unstructured play than those without siblings. Brothers and more closely spaced siblings spend more time together and more time in unstructured play. For example, boys with at least one brother spend five more hours per week with their siblings and over three more hours per week in unstructured play than boys with no brothers. Conclusions: The presence and characteristics of siblings shape children's time use in ways that may have implications for child development. Contribution: This is the first study to use children's time diary data to examine how the presence and characteristics of siblings structure ways in which children spend their time. This contributes to our broader understanding of sibling relationships and family dynamics.

Continuity of Genetic and Environmental Influences on Cognition across the Life Span: A Meta-Analysis of Longitudinal Twin and Adoption Studies

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Tucker-Drob, Elliot M.; Briley, Daniel A.

2014-01-01

The longitudinal rank-order stability of cognitive ability increases dramatically over the lifespan. Multiple theoretical perspectives have proposed that genetic and/or environmental mechanisms underlie the longitudinal stability of cognition, and developmental trends therein. However, the patterns of stability of genetic and environmental influences on cognition over the lifespan largely remain poorly understood. We searched for longitudinal studies of cognition that reported raw genetically-informative longitudinal correlations or parameter estimates from longitudinal behavior genetic models. We identified 150 combinations of time points and measures from 15 independent longitudinal samples. In total, longitudinal data came from 4,538 monozygotic twin pairs raised together, 7,777 dizygotic twin pairs raised together, 34 monozygotic twin pairs raised apart, 78 dizygotic twin pairs raised apart, 141 adoptive sibling pairs, and 143 non-adoptive sibling pairs, ranging in age from infancy through late adulthood. At all ages, cross-time genetic correlations and shared environmental correlations were substantially larger than cross-time nonshared environmental correlations. Cross-time correlations for genetic and shared environmental components were low during early childhood, increased sharply over child development, and remained relatively high from adolescence through late adulthood. Cross-time correlations for nonshared environmental components were low across childhood and increased gradually to moderate magnitudes in adulthood. Increasing phenotypic stability over child development was almost entirely mediated by genetic factors. Time-based decay of genetic and shared environmental stability was more pronounced earlier in child development. Results are interpreted in reference to theories of gene-environment interaction and correlation. PMID:24611582

Genetic Epidemiology of Spontaneous Subarachnoid Hemorrhage

DEFF Research Database (Denmark)

Korja, Miikka; Silventoinen, Karri; McCarron, Peter

2010-01-01

and 1 opposite sex) and 492 discordant twin pairs for SAH. The concordance for SAH in monozygotic twins was 3.1% compared with 0.27% in dizygotic twins, suggesting at most a modest role for genetic factors in the etiology of SAH. The population-based probability estimate for SAH in dizygotic siblings...... of a patient with SAH is 0.54%, and only 1 of 185 full siblings experience familial SAH. The corresponding risk of SAH in monozygotic twins is 5.9%. Model-fitting, which was based on the comparison of the few monozygotic and dizygotic pairs, suggested that the estimated heritability of SAH is 41%. CONCLUSIONS...

Cortical Excitability Measures in Patients and Unaffected Siblings

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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.

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

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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. (c) 2015 APA, all rights reserved).

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

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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...

Structural Features of Sibling Dyads and Attitudes toward Sibling Relationships in Young Adulthood

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Riggio, Heidi R.

2006-01-01

This study examined sibling-dyad structural variables (sex composition, age difference, current coresidence, position adjacency, family size, respondent and/or sibling ordinal position) and attitudes toward adult sibling relationships. A sample of 1,053 young adults (M age = 22.1 years) described one sibling using the Lifespan Sibling Relationship…

Twin-twin transfusion syndrome: neurodevelopment of infants treated with laser surgery

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Denise Campos

2016-04-01

Full Text Available ABSTRACT Objective To assess the neurodevelopmental functions of survivors of twin-twin transfusion syndrome (TTTS treated by fetoscopic laser coagulation (FLC, during the first year of life, comparing them to a control group; and to verify the influence of specific variables on neurodevelopment. Method This was a prospective, longitudinal study. The sample comprised 33 monochorionic diamniotic twins who underwent FLC for treatment of TTTS and 22 full-term infants of single-fetus pregnancies. Bayley Scales of Infant and Toddler Development Screening Test were used for evaluation. Prenatal, perinatal and postnatal information were obtained. Results There was an increased frequency of infants in the TTTS group with inadequate performance compared to the control group. The identified variables (fetal donor, low economic income and cardiorespiratory disease negatively impacted expressive communication and fine motor skills. Conclusion Although through follow-up is recommended in all TTTS survivors, particular attention is required for the high-risk group as defined in this study.

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

OpenAIRE

Pollet, Thomas; Nettle, Daniel

2009-01-01

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.

Xeroderma Pigmentosum: Variable Expressions among Three Siblings

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M Srinivasa Raju

2010-01-01

Full Text Available Xeroderma pigmentosum is a rare disorder transmitted in an autosomal recessive manner. It is characterized by photosensitivity, pigmentary changes, premature skin aging, and malignant tumor development. The frequency of this disorder is approximately 1 case per 250.000 population. Two important causes of mortality are metastatic malignant melanoma and squamous cell carcinoma. Here xeroderma pigmentosum in three siblings presenting with variable expressions is reported. The seventy of the condition was more in one of the more sun exposed sibling and had more signs of malignant lesions. Intraoral pigmentation was also present in all the three siblings.

Are elder siblings helpers or competitors? Antagonistic fitness effects of sibling interactions in humans

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Nitsch, Aïda; Faurie, Charlotte; Lummaa, Virpi

2013-01-01

Determining the fitness consequences of sibling interactions is pivotal for understanding the evolution of family living, but studies investigating them across lifetime are lacking. We used a large demographic dataset on preindustrial humans from Finland to study the effect of elder siblings on key life-history traits. The presence of elder siblings improved the chances of younger siblings surviving to sexual maturity, suggesting that despite a competition for parental resources, they may help rearing their younger siblings. After reaching sexual maturity however, same-sex elder siblings' presence was associated with reduced reproductive success in the focal individual, indicating the existence of competition among same-sex siblings. Overall, lifetime fitness was reduced by same-sex elder siblings' presence and increased by opposite-sex elder siblings' presence. Our study shows opposite effects of sibling interactions depending on the life-history stage, and highlights the need for using long-term fitness measures to understand the selection pressures acting on sibling interactions. PMID:23173210

And What About Siblings? A Longitudinal Analysis of Sibling Effects on Youth's Intergroup Attitudes.

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Eckstein, Katharina; Šerek, Jan; Noack, Peter

2018-02-01

Within the process of political socialization, the family is of particular importance. Apart from parents, however, little is known about the role of other close family members. The present study examined if siblings affect each other's intergroup attitudes (i.e., intolerance towards immigrants, social dominance orientation). Drawing on a sample of 362 sibling dyads (older siblings: M age  = 17.77, 53.6% female; younger siblings: M age  = 13.61, 61.3% female), the results showed that older siblings' intergroup attitudes predicted younger siblings' attitudes, but this effect was moderated by gender. Specifically, older siblings' intolerance and social dominance orientation were only found to affect their younger sisters, yet not their younger brothers. Although younger siblings' intergroup attitudes had no main effect on older siblings, a significant moderation by age indicated that younger siblings affected older siblings' social dominance orientation with increasing age. These moderation effects of age and gender were not mediated by the quality of family relationships. The findings also remained the same when parental intergroup attitudes were taken into account. While siblings were generally identified as an important agent of political socialization in youth, the results also highlight the necessity to further examine the mechanism that either facilitate or hinder sibling effects.

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

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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. PMID:26089806

Neonatal status of twins

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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.

Sibling relationships in adults who have siblings with or without intellectual disabilities.

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Doody, Mairéad A; Hastings, Richard P; O'Neill, Sarah; Grey, Ian M

2010-01-01

There is relatively little research on the relationships between adults with intellectual disability and their siblings, despite the potential importance of these relationships for either individual's psychological well-being and future care roles that might be adopted by adult siblings. In the present study, sibling relationships of adults with adult siblings with (N=63) and without (N=123) intellectual disability were explored. Contact, warmth, conflict, and rivalry were measured using questionnaires available as an on-line survey. Expressed emotion was measured using the Five Minute Speech Sample over the telephone to establish an independently coded measure of criticism from the participant towards their sibling. Overall, there were few group differences in contact and sibling relationship. There was less telephone contact in the intellectual disability group, and less reported warmth in the relationship with siblings with intellectual disability although this was mainly associated with severe/profound intellectual disability. Exploratory analyses were conducted of the correlates of sibling relationships in both the intellectual disability and control groups. These analyses revealed a small number of different associations especially for conflict, which was lower when either the participant or sibling was younger in the control group but associated with relative age in the intellectual disability group.

Is sibling rivalry fatal?: siblings and mortality clustering.

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Kippen, Rebecca; Walters, Sarah

2012-01-01

Evidence drawn from nineteenth-century Belgian population registers shows that the presence of similarly aged siblings competing for resources within a household increases the probability of death for children younger than five, even when controlling for the preceding birth interval and multiple births. Furthermore, in this period of Belgian history, such mortality tended to cluster in certain families. The findings suggest the importance of segmenting the mortality of siblings younger than five by age group, of considering the presence of siblings as a time-varying covariate, and of factoring mortality clustering into analyses.

'Biracial'-Looking Twins: A New Twin Type?/Twin Research: Twins with Cystic Teratomas; Sleep Quality and Body Mass Index; Previable Membrane Rupture/Print and Online Reports: Twins Born to a Sister Surrogate; NASA Twin Study; African-Cosmopolitan Twin Fashion Inspirations; Triplet Hockey Stars.

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Segal, Nancy L

2017-06-01

Dizygotic (DZ) co-twins born to mothers and fathers from different racial or ethnic backgrounds often resemble one parent much more than the other. As such, these pairs comprise a unique subset of twins for investigating how others' responses to their different looks may affect their personalities and self-esteem. This article describes some of these twin pairs and some challenges of raising them, and suggests ways they may be used in research. Next, recent twin research on cystic teratomas, relations between sleep quality and body mass index, and previable membrane rupture is described. The final section concerns twins, twin studies, and related events in the media, namely: twins born to a sister surrogate, the NASA twin investigation, inspiring African-Cosmopolitan twins in fashion, and triplet Hockey Stars.

Types of sons/siblings, fraternal function and peers

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Luisa Brunori

2013-12-01

Full Text Available In this article, the author starts by exploring family dynamics using the psychodynamic-groupanalytic paradigm to explore the intertwined relationships amongst the family figures like son, daughter, parents and sibling. The work focuses on the analysis of the psychological aspects related to siblings in the family, birth order and their consequences.

Remembering Irving I. Gottesman: Twin Research Colleague and Friend Extraordinaire/Research Studies: Face-Lift Technique Comparison in Identical Twins; Raising Preterm Twins; Fetal Behavior in Dichorionic Twin Pregnancies; Co-Bedding and Stress Reduction in Twins/Public Interest: Identical Co-Twins' Same Day Delivery; Teaching Twins in Bosnia; Twin Auctioneers; Sister, the Play.

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Segal, Nancy L

2016-12-01

Dr Irving I. Gottesman, a colleague, friend, and long-time member of the International Society of Twin Studies passed away on June 29, 2016. His contributions to twin research and some personal reflections are presented to honor both the man and the memory. This tribute is followed by short reviews of twin research concerning differences between cosmetic surgical techniques, the rearing of preterm twins, behavioral observations of dichorionic fetal twins, and the outcomes of co-bedding twins with reference to stress reduction. Interesting and informative articles in the media describe identical co-twins who delivered infants on the same day, educational policies regarding twins in Bosnia and the United Kingdom, unusual practices of twin auctioneers, and a theatrical production, Sister, featuring identical twins in the leading roles.

[Adult twins].

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Charlemaine, Christiane

2006-12-31

This paper explores the deep roots of closeness that twins share in their youngest age and their effect on their destiny at the adult age. Psychologists believe the bond between twins begins in utero and develops throughout the twins' lives. The four patterns of twinship described show that the twin bond is determined by the quality of parenting that twins receive in their infancy and early childhood. Common problems of adult twins bring about difficulties to adapt in a non-twin world. The nature versus nurture controversy has taken on new life focusing on inter-twin differences and the importance of parent-child interaction as fundamental to the growth and development of personality.

Sibling Relationships: Parent-Child Agreement and Contributions of Siblings with and without ASD

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Braconnier, Megan L.; Coffman, Marika C.; Kelso, Nicole; Wolf, Julie M.

2018-01-01

Research on the experiences of siblings of individuals with ASD and the quality of their sibling relationships has yielded mixed results. The present study examined the significance of parent- versus child-report of both positive and negative behaviors exhibited by siblings and their brothers and sisters with ASD within sibling dyads. Findings…

The Well Siblings of Schizophrenics.

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Samuels, Laurel; Chase, Laura

1979-01-01

Explores the impact of having a schizophrenic sibling. Subjects functioned at high levels of adjustment. Separated from their families, there followed a period of reinvolvement, including responsibility for the ill sibling. Younger siblings expressed guilt over being well, whereas older siblings expressed guilt over earlier sibling rivalry.…

Dichorionic Diamniotic Twin Pregnancy Discordant for Bladder Exstrophy

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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.

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.

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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.

The Placenta in Twin-to-Twin Transfusion Syndrome and Twin Anemia Polycythemia Sequence.

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Couck, Isabel; Lewi, Liesbeth

2016-06-01

Twin-to-twin transfusion syndrome (TTTS) and twin anemia polycythemia sequence (TAPS) are complications unique to monochorionic twin pregnancies and their shared circulation. Both are the result of the transfusion imbalance in the intertwin circulation. TTTS is characterized by an amniotic fluid discordance, whereas in TAPS, there is a severe discordance in hemoglobin levels. The article gives an overview of the typical features of TTTS and TAPS placentas.

Antenatal management of twin-twin transfusion syndrome and twin anemia-polycythemia sequence.

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Slaghekke, Femke; Zhao, Depeng P; Middeldorp, Johanna M; Klumper, Frans J; Haak, Monique C; Oepkes, Dick; Lopriore, Enrico

2016-08-01

Twin-twin transfusion syndrome (TTTS) and twin anemia polycythemia sequence (TAPS) are severe complications in monochorionic twin pregnancies associated with high mortality and morbidity risk if left untreated. Both diseases result from imbalanced inter-twin blood transfusion through placental vascular anastomoses. This review focuses on the differences in antenatal management between TTTS and TAPS. Expert commentary: The optimal management for TTTS is fetoscopic laser coagulation of the vascular anastomoses, preferably using the Solomon technique in which the whole vascular equator is coagulated. The Solomon technique is associated with a reduction of residual anastomosis and a reduction in post-operative complications. The optimal management for TAPS is not clear and includes expectant management, intra-uterine transfusion with or without partial exchange transfusion and fetoscopic laser surgery.

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

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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.

Do Older Siblings Make a Difference? The Effects of Older Sibling Support and Older Sibling Adjustment on the Adjustment of Socially Disadvantaged Adolescents.

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Widmer, Eric D.; Weiss, Christopher C.

2000-01-01

Examined role of support from a well-adjusted older sibling for positive adjustment of disadvantaged inner-city adolescents. Found that sibling support was nonsignificantly related to delinquency, academic success, and mental health for younger siblings. Only when accompanied by a positive image of their older sibling was support associated with…

A Possible Twin: The 1960s Twin Study Revisited/Twin Research: Twin-to-Twin Heart Transplantation; Distinguishing Monozygotic Twins; Twin Conceptions via Oocyte Donation; Factors Affecting Craniofacial Traits/In the Media: Triplet Delivery in the UK; Conjoined Twins and the Concept of Self; Colombian Twin Trainers; Skin Grafting to Save an Identical Co-Twin; Lack of Physical Flaws in Dolly the Cloned Sheep; Possible Conjoined Twins of Opposite-Sex; Passing of the Remaining Twin From the World's Longest Separated Pair.

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Segal, Nancy L

2018-04-01

This article begins with the story of a 51-year-old Los Angeles, California man, Justin Goldberg, whose daughter caught a glimpse of his striking look-alike at a popular market. Many people have so-called doppelgängers, but this occurrence is especially intriguing - the individual in question, born in New York City in the mid-1960s to an unwed mother, was an adoptee placed by the Louise Wise Adoption Agency. This agency, under the guidance of a prominent psychiatrist, decided to place twins in separate homes. Some of these twin children were part of a controversial child development study that was hidden from them and their parents. Next, recent and current twin research on heart transplantation, distinguishing monozygotic co-twins, twin conceptions via oocyte donation and factors affecting craniofacial traits are summarized. The article concludes with highlights on twins in the media, specifically, a triplet delivery in the United Kingdom, self-concept and consciousness in conjoined twins, Colombian twin trainers, skin grafting to save an identical co-twin, lack of physical flaws in Dolly the cloned sheep, possible opposite-sex conjoined twins, and the passing of the remaining twin from the world's longest separated pair.

Fingerprint recognition with identical twin fingerprints.

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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.

A maternal influence on Reading the mind in the Eyes mediated by executive function: differential parental influences on full and half-siblings.

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Gillian Ragsdale

Full Text Available BACKGROUND: Parent-of-origin effects have been found to influence the mammalian brain and cognition and have been specifically implicated in the development of human social cognition and theory of mind. The experimental design in this study was developed to detect parent-of-origin effects on theory of mind, as measured by the 'Reading the mind in the eyes' (Eyes task. Eyes scores were also entered into a principal components analysis with measures of empathy, social skills and executive function, in order to determine what aspect of theory of mind Eyes is measuring. METHODOLOGY/PRINCIPAL FINDINGS: Maternal and paternal influences on Eyes scores were compared using correlations between pairs of full (70 pairs, maternal (25 pairs and paternal siblings (15 pairs. Structural equation modelling supported a maternal influence on Eyes scores over the normal range but not low-scoring outliers, and also a sex-specific influence on males acting to decrease male Eyes scores. It was not possible to differentiate between genetic and environmental influences in this particular sample because maternal siblings tended to be raised together while paternal siblings were raised apart. The principal components analysis found Eyes was associated with measures of executive function, principally behavioural inhibition and attention, rather than empathy or social skills. CONCLUSIONS/SIGNIFICANCE: In conclusion, the results suggest a maternal influence on Eye scores in the normal range and a sex-specific influence acting to reduce scores in males. This influence may act via aspects of executive function such as behavioural inhibition and attention. There may be different influences acting to produce the lowest Eyes scores which implies that the heratibility and/or maternal influence on poor theory of mind skills may be qualitatively different to the influence on the normal range.

Sibling Relationships in Adults Who Have Siblings with or without Intellectual Disabilities

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Doody, Mairead A.; Hastings, Richard P.; O'Neill, Sarah; Grey, Ian M.

2010-01-01

There is relatively little research on the relationships between adults with intellectual disability and their siblings, despite the potential importance of these relationships for either individual's psychological well-being and future care roles that might be adopted by adult siblings. In the present study, sibling relationships of adults with…

Highlights from the 15th International Congress of Twin Studies/Twin Research: Differentiating MZ Co-twins Via SNPs; Mistaken Infant Twin-Singleton Hospital Registration; Narcolepsy With Cataplexy; Hearing Loss and Language Learning/Media Mentions: Broadway Musical Recalls Conjoined Hilton Twins; High Fashion Pair; Twins Turn 102; Insights From a Conjoined Twin Survivor.

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Segal, Nancy L

2015-02-01

Highlights from the 15th International Congress of Twin Studies are presented. The congress was held November 16-19, 2014 in Budapest, Hungary. This report is followed by summaries of research addressing the differentiation of MZ co-twins by single nucleotide polymorphisms (SNPs), an unusual error in infant twin-singleton hospital registration, twins with childhood-onset narcolepsy with cataplexy, and the parenting effects of hearing loss in one co-twin. Media interest in twins covers a new Broadway musical based on the conjoined twins Violet and Daisy Hilton, male twins becoming famous in fashion, twins who turned 102 and unique insights from a conjoined twin survivor. This article is dedicated to the memory of Elizabeth (Liz) Hamel, DZA twin who met her co-twin for the first time at age seventy-eight years. Liz and her co-twin, Ann Hunt, are listed in the 2015 Guinness Book of Records as the longest separated twins in the world.

Self-Representations in Early Adolescence: Variations in Sibling Similarity by Sex Composition and Sibling Relationship Qualities

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Gamble, Wendy C.; Card, Noel A.; Yu, Jeong Jin

2010-01-01

Self-representations play an important role in adolescent development. This study compared self-representations for siblings and explored whether sibling relationship characteristics are associated with similarities or differences in sibling self-concepts. We examined self-representations of 438 adolescent sibling dyads (M age younger sibling =…

Theoretical Perspectives on Sibling Relationships

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Whiteman, Shawn D.; McHale, Susan M.; Soli, Anna

2011-01-01

Although siblings are a fixture of family life, research on sibling relationships lags behind that on other family relationships. To stimulate interest in sibling research and to serve as a guide for future investigations by family scholars, we review four theoretical psychologically oriented perspectives—(a) psychoanalytic-evolutionary, (b) social psychological, (c) social learning, and (d) family-ecological systems—that can inform research on sibling relationships, including perspectives on the nature and influences on developmental, individual, and group differences in sibling relationships. Given that most research on siblings has focused on childhood and adolescence, our review highlights these developmental periods, but we also incorporate the limited research on adult sibling relationships, including in formulating suggestions for future research on this fundamental family relationship. PMID:21731581

The influence of heritability, neuroticism, maternal warmth and media use on disordered eating behaviors: a prospective analysis of twins.

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Ferguson, Christopher J; Muñoz, Monica E; Winegard, Ben; Winegard, Bo

2012-09-01

The relative impact of genetic and social influences on disordered eating behaviors (DEB) including binging, purging, excessive dieting and negative self-evaluations about weight remain an issue of debate. The current study sought to examine the relative influence of genetic and social influences on DEB. A 7-year prospective analysis of 580 monozygotic (MZ) and dizygotic (DZ) twins was conducted. Estimates of heritability of DEB were obtained using the DF Analysis Model. Regression equations revealed the relative predictive value of sibling's DEB, neurotic personality, maternal warmth and television and video game exposure on DEB. Heritability estimates for DEB were 0.40 for females and 0.48 for males. Among MZ and DZ twin pairs, female sex, neurotic personality and a genetic variable component, but not maternal warmth or school related problems, predicted DEB. Contrary to the expectations of media effects theory, greater media use was associated with lower DEB among DZ twins and had no influence on MZ twins. These results indicate that DEB is highly heritable and that personality variables may play an important role in the formation of DEB. This suggests that it is important to control for genetic variables when analyzing risk factors for DEB.

From Parents to Siblings and Peers

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Isabelle Roskam

2015-10-01

Full Text Available The objective of the current research was to test the hypotheses arising from the epigenetic view of social development and from the wider perspective offered by the social network model with three interactional systems, that is, child–parent, child–sibling, and child–peer. They were tested in two prospective longitudinal studies using a multi-informant and multi-method strategy. Study 1 was conducted among 83 children and their parents and Study 2 among 190 children. Attachment security with parents was assessed when the children were 4 years of age, relationships with siblings at 5 years of age, and relationships with peers at 6 years of age. Attachment to parent was found to explain a limited part of variations in later social relationships with siblings and peers. The sibling interactional system had a consistent and enduring effect on later peer relationships. With regard to the two theoretical backgrounds under consideration, neither was able to account for equivocal findings displayed in the two studies as well as in previous research. The wonderful story of social development seems to be a very complex process for which new models are needed.

CMV infection associated with severe lung involvement and persistent pulmonary hypertension of the newborn (PPHN) in two preterm twin neonates.

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Manzoni, Paolo; Vivalda, Mauro; Mostert, Michael; Priolo, Claudio; Galletto, Paolo; Gallo, Elena; Stronati, Mauro; Gili, Renata; Opramolla, Anna; Calabrese, Sara; Tavella, Elena; Luparia, Martina; Farina, Daniele

2014-09-01

The diagnosis of congenital CMV is usually guided by a number of specific symptoms and findings. Unusual presentations may occur and diagnosis is challenging due to uncommon or rare features. Here we report the case of two preterm, extremely low birthweight, 28-week gestational age old twin neonates with CMV infection associated with severe lung involvement and persistent pulmonary hypertension of the newborn (PPHN). They were born to a HIV-positive mother, hence they underwent treatment with zidovudine since birth. Both infants featured severe refractory hypoxemia, requiring high-frequency ventilation, inhaled nitric oxide and inotropic support, with full recovery after 2 months. Treatment with ganciclovir was not feasible due the concomitant treatment with zidovudine and the risk of severe, fatal toxicity. Therefore administration of intravenous hyperimmune anti-CMV immunoglobulin therapy was initiated. Severe lung involvement at birth and subsequent pulmonary hypertension are rarely described in preterm infants as early manifestations of CMV congenital disease. In the two twin siblings here described, the extreme prematurity and the treatment with zidovudine likely worsened immunosuppression and ultimately required a complex management of the CMV-associated lung involvement. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Child passenger injury risk in sibling versus non-sibling teen driver crashes: a US study.

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Senserrick, Teresa M; Kallan, Michael J; Winston, Flaura K

2007-06-01

Several international jurisdictions allow family exemptions to graduated driver licensing passenger restrictions. The objective of this research was to examine differences in injury risk to US child passengers in crashes involving sibling versus non-sibling teen drivers, and to compare outcomes with crashes involving adult drivers. Insurance claim and telephone survey data were collected on 16 233 child passengers (representing 289 329 children) in 17 US jurisdictions. There was a trend toward higher restraint non-use by child passengers in the non-sibling group than in the sibling group (9.6% vs 4.7%; p = 0.08). Children in the sibling group had a 40% lower risk of injury than those in the non-sibling group (adjusted OR 0.60, 95% CI 0.40 to 0.90); however, injury risk was higher in the sibling group than in children traveling with adults (adjusted OR 1.57, 95% CI 1.09 to 2.26). Child passengers riding with sibling teen drivers may be safer than those riding with non-sibling teens, but not as safe as those riding with adult drivers.

Relationships between parenting and adolescent adjustment over time: genetic and environmental contributions.

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Neiderhiser, J M; Reiss, D; Hetherington, E M; Plomin, R

1999-05-01

The predictive association between parenting and adolescent adjustment has been assumed to be environmental; however, genetic and environmental contributions have not been examined. This article represents one effort to examine these associations in which a genetically informative design was used. Participants were 395 families with adolescent siblings who participated in the Nonshared Environment in Adolescent Development (D. Reiss et al., 1994) project at 2 times of assessment, 3 years apart. There were 5 sibling types in 2 types of families: 63 identical twins, 75 fraternal twins, and 58 full siblings in nondivorced families and 95 full, 60 half, and 44 genetically unrelated siblings in stepfamilies. Results indicate that the cross-lagged associations between parental conflict-negativity and adolescent antisocial behavior and depressive symptoms can be explained primarily by genetic factors. These findings emphasize the need to recognize and examine the impact that adolescents have on parenting and the contribution of genetic factors to developmental change.

Sibling influence on mexican-origin adolescents' deviant and sexual risk behaviors: the role of sibling modeling.

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Whiteman, Shawn D; Zeiders, Katharine H; Killoren, Sarah E; Rodriguez, Sue Annie; Updegraff, Kimberly A

2014-05-01

A growing body of research indicates that siblings uniquely influence each other's health risk behaviors during adolescence and young adulthood. Mechanisms underlying these associations, however, are largely unknown because they are rarely tested directly. The present study addressed this gap by examining the role of sibling modeling in explaining changes in Mexican-origin youths' deviant and sexual risk behaviors over time. The sample included 380 Mexican-origin siblings (older sibling age: M = 21.18, SD = 1.59; younger sibling age: M = 18.19, SD = .46) from (N = 190) families. Participants provided self-reports of their sibling relationship qualities, including modeling, as well as their engagement in deviant and sexual risk-taking behaviors in two home interviews across a 2-year span. A series of residualized regression models revealed that younger siblings' perceptions of modeling moderated the links between older siblings' deviant and sexual risk behaviors and younger siblings' subsequent behaviors in those same domains. Specifically, high levels of modeling predicted stronger associations between older siblings' earlier and younger siblings' later risk behaviors controlling for younger siblings' earlier behaviors as well as variables that have been used as proxies for social learning in previous research. Social learning mechanisms, especially modeling, are salient processes through which older siblings transmit norms and expectations regarding participation in health risk behaviors. Future research should continue to explore the ways in which siblings influence each other because such processes are emerging targets for intervention and prevention. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Gratitude for Help among Adult Friends and Siblings

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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.

Parental Differential Treatment of Siblings in Childhood

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Tina Kavčič

2007-03-01

Full Text Available Parental differential treatment is an important feature of non-shared family environment which contributes to the development of behavioural differences between siblings growing up in the same family. To investigate the frequency, direction, and patterns of parental differential treatment of siblings in Slovene families, mothers and fathers of 93 sibling-pairs in early/middle childhood provided self-reports in a two-wave longitudinal study. Most of the parents reported on low levels of differential treatment, predominantly expressing somewhat more affection and control towards the older than towards the younger sibling. Over a one-year time period, the average frequency of parental differential treatment did not change significantly, whereas the stability was estimated as moderate for maternal and low for paternal assessments. Maternal and paternal self-ratings were moderately correlated. However, the mothers reported on somewhat higher levels of differential control and (only in wave 1 affection than the fathers. Nearly half of the families were characterized by a congruent pattern of parental differential treatment indicating that both parents showed more affection and control towards the older of the two siblings. A complementary family pattern reflecting an opposite direction of maternal and paternal differential treatment emerged in approximately a quarter of the participating families.

Sibling influences on prosocial behavior.

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Hughes, Claire; McHarg, Gabrielle; White, Naomi

2018-04-01

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.

Considerations of Elder Sibling Closeness in Predicting Younger Sibling Substance Use: Social Learning versus Social Bonding Explanations

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Samek, Diana R.; Rueter, Martha A.

2011-01-01

Adolescent siblings are often similar in a variety of adjustment outcomes, yet little is known about the processes that explain sibling influences during adolescence. Two alternative explanations were tested, attachment (based in social bonding theory) and anaclitic identification (based in social learning theory). Hypotheses were tested using a sample of 613 adolescent sibling pairs (206 non-adopted, 407 adopted; elder sibling Mage = 16.1, younger sibling Mage = 13.8) across three sibling contexts (gender composition, age difference, and genetic similarity). Attachment explanations were supported such that the greater the perceived sibling emotional and behavioral closeness, the lower the likelihood of substance use; however, there were considerable moderating effects of sibling gender composition. Anaclitic identification explanations were not supported; closeness and elder sibling substance use did not interact to predict younger sibling substance use. Overall, this research adds to a body of work demonstrating important sibling influences on adolescent substance use. PMID:21988080

Sibling influences on childhood development.

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Dunn, J

1988-03-01

To summarize the main points concerning sibling influence: 1. That siblings play a causal role in the development of aggressive behavior, in children's style of conflict behavior and in cooperative fantasy play is strongly suggested by recent research. 2. Marked problems in the sibling relationship are indicative of other problems, but a causal role for siblings is not established, other than for aggressive behavior. 3. Family factors are closely involved in the quality of sibling relationships--and thus in sibling influence, namely differential parental behavior, and the emotional climate of the family. That is, it is important not to consider the sibling relationship in isolation from other family relationships. 4. Studies of families under stress indicate heightened importance of these family factors. 5. It is likely, but not yet established, that later-born siblings are influenced by first-born in socio-cognitive development and gender identity. 6. Finally it should be noted that an important theme in current research on siblings is a concern with the question of why siblings develop to be so different from one another. It has been shown that the major source of environmental influence on the development of individual differences is within-family rather than between-family differences in experience (Plomin & Daniels, 1987). The different experiences each sibling may have within their relationship is one potential source of such differential environmental influence. Thus documenting the influence of siblings upon each other takes on added significance: By clarifying the extent and nature of this influence we will gain not only useful clinical information but illumination on a developmental principle of very general significance.

Upaya Mengatasi Sibling Rivalry melalui Layanan Konseling Kelompok

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Eli Turniati

2015-12-01

Full Text Available Penelitian ini dilakukan berdasarkan fenomena yang terjadi pada siswa kelas VI SDN Sendangmulyo 02 kecamatan Tembalang kota Semarang yang mengalami sibling rivalry. Tujuan penelitian ini yaitu untuk mengetahui apakah konseling kelompok dapat mengatasi sibling rivalry pada siswa kelas VI SDN Sendangmulyo 02. Jenis penelitian adalah penelitian eksperiment dengan desain penelitian one group pre-test dan pos-test design. Subyek penelitian ini, siswa kelas VI SDN Sendangmulyo 02 yang memiliki tingkat sibling rivalry tinggi yang diperoleh dari hasil DCM dan rekomendasi dari guru kelas yaitu terjaring 10 siswa. Metode pengumpulan data menggunakan skala psikologis berupa skala sibling rivalry. Analisis data menggunakan teknik analisis data deskriptif persentase dan uji wilcoxon. Hasil penelitian menunjukan sibling rivalry siswa sebelum diberi perlakuan berupa konseling kelompok dalam kategori tinggi (75.14%. Setelah diberikan konseling kelompok menunjukkan perbedaan, dilihat dari hasil pos test rata-rata sibling rivalry siswa menurun yaitu berada pada kategori rendah (42,95%. Hal tersebut menunjukan bahwa sibling rivalry dapat diatasi melalui layanan konseling kelompok This research was conducted based on phenomena that occur in grade VI SDN Sendangmulyo 02 Tembalang Semarang who experienced sibling rivalry. The purpose of this research is to find out if counseling groups can overcome sibling rivalry at grade VI SDN Sendangmulyo 02. This type of research is research research design alphabets experiment one group pre test and post test design. The subject of this study, students of class VI SDN Sendangmulyo 02 that has a high level of sibling rivalry that results obtained from DCM and the recommendations of the master class that is netted 10 students. Method of data collection using a scale of psychological scale in the form of sibling rivalry. Data analysis data analysis techniques using a descriptive percentage and wilcoxon test. The research results

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…

Molecular dynamics simulation of albite twinning and pericline twinning in low albite

International Nuclear Information System (INIS)

Li, Bin; Knowles, Kevin M

2013-01-01

Two twinning laws, the albite law and the pericline law, are the predominant growth twinning modes in triclinic plagioclase feldspars such as low albite, NaAlSi 3 O 8 , in which the aluminum and silicon atoms are in an ordered arrangement on the tetrahedral sites of the aluminosilicate framework. In the terminology used formally to describe deformation twinning in a triclinic lattice, these twin laws can be described as Type I and Type II twin laws, respectively, with the pericline twin law being conjugate to the albite twin law. In this study, twin boundaries have been constructed for low albite according to these two twinning laws and studied by molecular dynamics simulation. The results show that suitably constructed twin boundary models are quite stable for both albite twinning and pericline twinning during molecular dynamics simulation. The calculated twin boundary energy of an albite twin is significantly lower than that of a pericline twin, in accord with the experimental observation that albite twinning is the more commonly observed mode seen in plagioclase feldspars. The results of the molecular dynamics simulations also agree with conclusions from the prior work of Starkey that glide twinning in low albite is not favoured energetically. (paper)

Bullying in the family: sibling bullying.

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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.

Art for twins: Yorùbá artists and their statues/twin research studies: twins' education and conceptions; diurnal preference; inherited eye diseases; ultrasound counseling when twins are conjoined/popular twin reports: twin sisters (the film); rare pregnancy; diet test; French twins reared apart and reunited.

Science.gov (United States)

Segal, Nancy L

2014-06-01

The Yorùbá of Nigeria are well known for their high twinning rate and the statues they create to commemorate deceased twins. An impressive collection of this artwork was displayed at the University of California's Fowler Museum in Los Angeles between October 13, 2013 and March 2, 2014. An overview of this exhibit is provided. Next, twin research on maternal education and conception, diurnal preference, inherited eye diseases, and ultrasound counseling for couples with conjoined twins are briefly summarized. This article concludes with a discussion of media-based items related to twins. The topics include an award-winning twin film, a rare pregnancy, a diet test, and the separation and chance reunion of monozygotic female twins.

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

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Timothy P York

Full Text Available 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.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.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.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.

Dental and skeletal changes in mild to moderate Class II malocclusions treated by either a Twin-block or Xbow appliance followed by full fixed orthodontic treatment.

Science.gov (United States)

Ehsani, Sayeh; Nebbe, Brian; Normando, David; Lagravere, Manuel O; Flores-Mir, Carlos

2015-11-01

To compare the short-term skeletal and dental effects of two-phase orthodontic treatment including either a Twin-block or an XBow appliance. This was a retrospective clinical trial of 50 consecutive Class II cases treated in a private practice with either a Twin-block (25) or XBow (25) appliance followed by full fixed orthodontic treatment. To factor out growth, an untreated Class II control group (25) was considered. A MANOVA of treatment/observation changes followed by univariate pairwise comparisons showed that the maxilla moved forward less in the treatment groups than in the control group. As for mandibular changes, the corpus length increase was larger in the Twin-block group by 3.9 mm. Dentally, mesial movement of mandibular molars was greater in both treatment groups. Although no distalization of maxillary molars was found in either treatment group, restriction of mesial movement of these teeth was seen in both treatment groups. Both treatment groups demonstrated increased mandibular incisor proclination with larger increases for the XBow group by 3.3°. The Wits value was decreased by 1.6 mm more in the Twin-block group. No sex-related differences were observed. Class II correction using an XBow or Twin-block followed by fixed appliances occurs through a relatively similar combination of dental and skeletal effects. An increase in mandibular incisor inclination for the XBow group and an increased corpus length for the Twin-block group were notable exceptions. No overall treatment length differences were seen.

Anaesthesia for the separation of conjoined twins

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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.

Conjoined twins detected in the first trimester: A review

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Chih-Ping Chen

2011-12-01

Full Text Available Conjoined twinning occurs in 1 in 100 sets of monozygotic twins, 1 in 50,000 gestations or 1 in 250,000 live births. With the advent of ultrasound technology, prenatal diagnosis of conjoined twins is possible. This article provides a comprehensive review of conjoined twins detected in the first trimester including fetal gender, maternal age, parity, types of fusion, related ultrasound abnormalities, perinatal outcome and association with assisted reproduction.

Prosocial and self-interested intra-twin pair behavior in monozygotic and dizygotic twins in the early to middle childhood transition.

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Yirmiya, Karen; Segal, Nancy L; Bloch, Guy; Knafo-Noam, Ariel

2018-04-06

Several related and complementary theoretical frameworks have been proposed to explain the existence of prosocial behavior, despite its potential fitness cost to the individual. These include kin selection theory, proposing that organisms have a propensity to help those to whom they are genetically related, and reciprocity, referring to the benefit of being prosocial, depending on past and future mutual interactions. A useful paradigm to examine prosociality is to compare mean levels of this behavior between monozygotic (MZ) and dizygotic (DZ) twins. Here, we examined the performance of 883 6.5-year-old twins (139 MZ and 302 DZ same-sex 6.5-year-old full twin pairs) in the Differential Productivity Task. In this task, the twins' behaviors were observed under two conditions: working for themselves vs. working for their co-twin. There were no significant differences between the performances of MZ and DZ twins in the prosocial condition of the task. Correlations within the twin dyads were significantly higher in MZ than DZ twins in the self-interested condition. However, similar MZ and DZ correlations were found in the prosocial condition, supporting the role of reciprocity in twins' prosociality towards each other. © 2018 John Wiley & Sons Ltd.

Quality of Sibling Relationship and Substance Misuse: A Comparative Study

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Anastasia Tsamparli

2016-03-01

Full Text Available The aim of the current study is to examine the quality of sibling relationship in families with a sibling with substance misuse (SSU and compare the relationship to families with a sibling with no use (SNU. Thirty-six (36 families participated in the study (17 with SSU and 19 with SNU; N = 144. Semi-structured interviews were conducted with 40 siblings (20 SNU and 20 SSU; 18-31 years old in order to qualitatively investigate the characteristics of the sibling relationship. The siblings were not identified with any psychopathology, according to SCL-90R. Moreover, we considered the family cohesion and adaptability, as identified by the FACES III (administered to the whole sample and the family constellation (including number of children, birth order, gender, family size, family structure, years of substance misuse and socioeconomic level. The results of the thematic analysis seem to support Furman and Buhrmester’s (1985 framework, in the context of SNU families. Nevertheless, when considering families with SSU the framework is enriched with a new axis: Loss/mourning. The substance misuse seems to provoke an overturn of the representation of the sibling relationship: the behavioral changes (i.e. disengagement of the sibling with drug use are experienced as a loss by the sibling non user, thus triggering the psychological process of ‘mourning’. Moreover, in these families, the sibling with no drug use seem to experience differential parenting, they feel neglected, angry and they take up a parental role towards the SSU, whom they experience as “sensitive” and “vulnerable”.

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

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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).

Associations between social understanding, sibling relationship quality, and siblings' conflict strategies and outcomes.

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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 with positive conflict processes. Younger siblings' second-order false belief scores were negatively associated with constructive conflict strategies, and older siblings' narrative self-referential focus was negatively associated with compromise. Associations between younger children's social understanding (conflict interpretation and narrative perspective references) and siblings' dyadic conflict behavior were moderated by relationship quality. Results suggest that links between social understanding and conflict behavior should be considered in conjunction with the quality of children's relationships.

Twinning of Polymer Crystals Suppressed by Entropy

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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.

Fast half-sibling population reconstruction: theory and algorithms.

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Dexter, Daniel; Brown, Daniel G

2013-07-12

Kinship inference is the task of identifying genealogically related individuals. Kinship information is important for determining mating structures, notably in endangered populations. Although many solutions exist for reconstructing full sibling relationships, few exist for half-siblings. We consider the problem of determining whether a proposed half-sibling population reconstruction is valid under Mendelian inheritance assumptions. We show that this problem is NP-complete and provide a 0/1 integer program that identifies the minimum number of individuals that must be removed from a population in order for the reconstruction to become valid. We also present SibJoin, a heuristic-based clustering approach based on Mendelian genetics, which is strikingly fast. The software is available at http://github.com/ddexter/SibJoin.git+. Our SibJoin algorithm is reasonably accurate and thousands of times faster than existing algorithms. The heuristic is used to infer a half-sibling structure for a population which was, until recently, too large to evaluate.

The effect of chorionicity and twin-to-twin delivery time interval on short-term outcome of the second twin

DEFF Research Database (Denmark)

Hjortø, Sofie; Nickelsen, Carsten; Petersen, Janne

2013-01-01

Abstract Objectives: To investigate the effect of chorionicity and twin-to-twin delivery time interval on short-term outcome in the second twin. Additionally, to investigate predictors of adverse outcome in both twins. Methods: Data included vaginally delivered twins (≥ 36 weeks) from Copenhagen ...

Confined Blood Chimerism in Monochorionic Dizygotic Twins Conceived Spontaneously

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Takashi Kanda

2013-05-01

Full Text Available Traditionally, monochorionicity has been regarded as synonymous with monozygosity. However, several recent cases of monochorionic dizygotic twins have shown that monochorionic twins can be dizygous. We report a rare case of monochorionic diamnionic, gender-discordant twins who were conceived spontaneously. Initially, a monochorionic placenta was diagnosed by ultrasonography at 8 weeks of gestation and then confirmed by pathology after delivery. The twins had different genders. A comparison of cytogenetic analyses using peripheral blood lymphocytes and skin fibroblasts revealed that chimerism was confined to blood cells. We have experienced two cases of monochorionic dizygotic twins since 2003. These cases suggest that monochorionic dizygotic twins are not as rare as previously thought.

Undiagnosed xiphopagus twins: a perinatal malady

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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.

Siblings' coping strategies and mental health services: a national study of siblings of persons with schizophrenia.

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Friedrich, Rose Marie; Lively, Sonja; Rubenstein, Linda M

2008-03-01

This study examined the helpfulness of coping strategies and the relative importance of mental health services in coping with schizophrenia from the perspective of siblings. This article presents selected survey data from a national study of 746 respondents that investigated the impact of schizophrenia on siblings' lives. The authors developed the Friedrich-Lively Instrument to Assess the Impact of Schizophrenia on Siblings (FLIISS), a closed-ended questionnaire that included questions about coping strategies and mental health services. Respondents identified services for the ill sibling, including symptom control, adequate housing, and long-term planning, as more important than direct services for themselves. The top-ranked coping strategies were education about schizophrenia, a supportive family, and seeing the ill sibling suffer less because symptoms were controlled. Understanding that families were not to blame for schizophrenia was the most helpful coping strategy for nearly three-fourths of siblings. Siblings had little contact with providers in the past; yet the majority of siblings wanted providers to be available to answer questions and clarify their role in future care. At the time of the study, respondents provided social support and helped with crises, but few coordinated the total care. Siblings identified multiple ways that providers can support and assist them in coping with the impact of schizophrenia. Education and support for siblings without schizophrenia and services for their ill siblings will become increasingly important for the well-being of siblings as they are faced with the responsibility of being the primary caregivers in the future.

Self-reported behaviour problems and sibling relationship quality by siblings of children with autism spectrum disorder.

Science.gov (United States)

Hastings, R P; Petalas, M A

2014-11-01

There are few published research studies in which siblings of children with autism spectrum disorder (ASD) provide self-reports about their own behavioural and emotional problems and their sibling relationships. Reliance on parent reports may lead to incomplete conclusions about the experiences of siblings themselves. Siblings 7-17 years and their mothers from 94 families of children with ASD were recruited. Mothers reported on family demographics, the behavioural and emotional problems of their child with ASD, and on their own symptoms of depression. Siblings reported on their relationship with their brother or sister with ASD, and siblings 11+ years of age also self-reported on their behavioural and emotional problems. Compared with normative British data, siblings reported very slightly elevated levels of behavioural and emotional problems. However, none of the mean differences were statistically significant and all group differences were associated with small or very small effect sizes - the largest being for peer problems (effect size = 0.31). Regression analysis was used to explore family systems relationships, with sibling self-reports predicted by the behaviour problems scores for the child with ASD and by maternal depression. Maternal depression did not emerge as a predictor of siblings' self-reported sibling relationships or their behavioural and emotional problems. Higher levels of behaviour problems in the child with ASD predicted decreased warmth/closeness and increased conflict in the sibling relationship. These data support the general findings of recent research in that there was little indication of clinically meaningful elevations in behavioural and emotional problems in siblings of children with ASD. Although further research replication is required, there was some indication that sibling relationships may be at risk where the child with ASD has significant behaviour problems. © 2014 John Wiley & Sons Ltd.

Genetic and environmental determinants of violence risk in psychotic disorders: a multivariate quantitative genetic study of 1.8 million Swedish twins and siblings.

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Sariaslan, A; Larsson, H; Fazel, S

2016-09-01

Patients diagnosed with psychotic disorders (for example, schizophrenia and bipolar disorder) have elevated risks of committing violent acts, particularly if they are comorbid with substance misuse. Despite recent insights from quantitative and molecular genetic studies demonstrating considerable pleiotropy in the genetic architecture of these phenotypes, there is currently a lack of large-scale studies that have specifically examined the aetiological links between psychotic disorders and violence. Using a sample of all Swedish individuals born between 1958 and 1989 (n=3 332 101), we identified a total of 923 259 twin-sibling pairs. Patients were identified using the National Patient Register using validated algorithms based on International Classification of Diseases (ICD) 8-10. Univariate quantitative genetic models revealed that all phenotypes (schizophrenia, bipolar disorder, substance misuse, and violent crime) were highly heritable (h(2)=53-71%). Multivariate models further revealed that schizophrenia was a stronger predictor of violence (r=0.32; 95% confidence interval: 0.30-0.33) than bipolar disorder (r=0.23; 0.21-0.25), and large proportions (51-67%) of these phenotypic correlations were explained by genetic factors shared between each disorder, substance misuse, and violence. Importantly, we found that genetic influences that were unrelated to substance misuse explained approximately a fifth (21%; 20-22%) of the correlation with violent criminality in bipolar disorder but none of the same correlation in schizophrenia (Pbipolar disordergenetically similar phenotypes as the latter sources may include aetiologically important clues. Clinically, these findings underline the importance of assessing risk of different phenotypes together and integrating interventions for psychiatric disorders, substance misuse, and violence.

Twin Research and the Arts: Interconnections / Twin Research: Twin Studies of Sexual Orientation; A Historical Biological Twin Gem; GWAS Approach to Who Has Twins / Newsworthy: Twins on College Campuses; 'Brainprint': Personal Identification by Brain Waves.

Science.gov (United States)

Segal, Nancy L

2016-08-01

The interrelatedness between twin research and the arts is explored via a new play about a famous case. In the 1960s, identical twin David Bruce Reimer was accidentally castrated as an infant during circumcision to correct a urinary problem. The decision to raise him as a girl, and the consequences of that decision, are explored in the new theatrical production of Boy. Other examples of the arts mirroring science, and vice versa, are described. Next, brief reviews and summaries of twin research on sexual orientation, 1860s' knowledge of placental arrangements and twinning mechanisms, and genes underlying multiple birth conception and fertility related measures are provided. This article concludes with a look at twins on college campuses and the identification of individuals by their brain waves. A correction and clarification regarding my article on the Brazilian Twin Registry in the last issue of THG (Segal, 2016) is also provided.

Enhancing sibling relationships to prevent adolescent problem behaviors: theory, design and feasibility of Siblings Are Special.

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Feinberg, Mark E; Sakuma, Kari-Lyn; Hostetler, Michelle; McHale, Susan M

2013-02-01

Siblings play a significant but neglected role in family socialization dynamics, and focusing on the sibling relationship is a non-stigmatizing point of entry into the family for prevention programming. Siblings are Special (SAS) was designed as a universal program that targets both sibling relationship and parenting mediating processes in middle childhood to prevent behavior problems in adolescence. We describe the theoretical framework underlying SAS, the SAS curriculum, and the feasibility of the program based on a study of 128 middle-childhood aged sibling dyads. Data on the quality of program implementation, program fidelity, siblings' engagement, and ratings of impact indicated the SAS program was acceptable to families and schools, that the curriculum could be implemented with high fidelity, that siblings and parents participated at high levels and were highly engaged, and that, from the perspective of group leaders, school administrators and parents, the program had a positive impact on the siblings. Copyright © 2012 Elsevier Ltd. All rights reserved.

Progeria in siblings: A rare case report

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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.

Intragranular twinning, detwinning, and twinning-like lattice reorientation in magnesium alloys

International Nuclear Information System (INIS)

Wu, Wei; Gao, Yanfei; Li, Nan; Parish, Chad M.; Liu, Wenjun; Liaw, Peter K.; An, Ke

2016-01-01

Deformation twinning plays a critical role on improving metals or alloys ductility, especially for hexagonal close-packed materials with low symmetry crystal structure. A rolled Mg alloy was selected as a model system to investigate the extension twinning behaviors and characteristics of parent-twin interactions by nondestructive in situ 3D synchrotron X-ray microbeam diffraction. Besides twinning-detwinning process, the “twinning-like” lattice reorientation process was captured within an individual grain inside a bulk material during the strain reversal. The distributions of parent, twin, and reorientated grains and sub-micron level strain variation across the twin boundary are revealed. A theoretical calculation of the lattice strain confirms that the internal strain distribution in parent and twinned grains correlates with the experimental setup, grain orientation of parent, twin, and surrounding grains, as well as the strain path changes. The study suggests a novel deformation mechanism within the hexagonal close-packed structure that cannot be determined from surface-based characterization methods.

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.

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

Science.gov (United States)

Stewart, Christopher J; Marrs, Emma C L; Nelson, Andrew; Lanyon, Clare; Perry, John D; Embleton, Nicholas D; Cummings, Stephen P; Berrington, Janet E

2013-01-01

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.

Relative Power in Sibling Relationships Across Adolescence.

Science.gov (United States)

Lindell, Anna K; Campione-Barr, Nicole

2017-06-01

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 is known about relationship factors that may explain this shift in power dynamics, however. The present study therefore examined longitudinal changes in adolescents' and their siblings' perceptions of sibling relative power from age 12 to 18 (n = 145 dyads), and examined whether different levels of sibling relationship positivity and negativity, as well as sibling structural variables, indicated different over-time changes in relative power. Multilevel models indicated that adolescents reported significant declines in their siblings' relative power across adolescence, with older siblings relinquishing the most power over time. However, only siblings with less positively involved relationships reported declines in relative power, suggesting that siblings who maintain highly involved relationships may not become more egalitarian during adolescence. © 2017 Wiley Periodicals, Inc.

Tensions among siblings in parent care.

Science.gov (United States)

Lashewicz, Bonnie; Keating, Norah

2009-06-01

From a place of "genealogical equivalence" as children of their parents, siblings spend a lifetime developing separate identities. As parents near the end of their lives, issues of sibling equivalence are renegotiated in the face of equal obligations to provide care and equal entitlement to parent assets. In this paper, we hypothesize how unresolved issues of rivalry for parent affection/attention among siblings may be reasserted when parents need care. Data are drawn from a project about how parent care and assets are shared. In-depth interviews with three sibling groups experiencing conflict over sharing parent care and assets along with six Canadian legal case portrayals of disputes among siblings over how parent care and assets were shared are examined. Findings are that disputes occur when siblings perceive others as dominating parent care and assets through tactics such as separating the parent from other siblings and preventing other siblings from being engaged in decisions about care and assets. Discussion is focused on paradoxes faced by siblings given expectations for equity in parent relationships alongside perceived pre-eminence in care and asset decisions.

Sibling Competition & Growth Tradeoffs. Biological vs. Statistical Significance.

Directory of Open Access Journals (Sweden)

Karen L Kramer

Full Text Available Early childhood growth has many downstream effects on future health and reproduction and is an important measure of offspring quality. While a tradeoff between family size and child growth outcomes is theoretically predicted in high-fertility societies, empirical evidence is mixed. This is often attributed to phenotypic variation in parental condition. However, inconsistent study results may also arise because family size confounds the potentially differential effects that older and younger siblings can have on young children's growth. Additionally, inconsistent results might reflect that the biological significance associated with different growth trajectories is poorly understood. This paper addresses these concerns by tracking children's monthly gains in height and weight from weaning to age five in a high fertility Maya community. We predict that: 1 as an aggregate measure family size will not have a major impact on child growth during the post weaning period; 2 competition from young siblings will negatively impact child growth during the post weaning period; 3 however because of their economic value, older siblings will have a negligible effect on young children's growth. Accounting for parental condition, we use linear mixed models to evaluate the effects that family size, younger and older siblings have on children's growth. Congruent with our expectations, it is younger siblings who have the most detrimental effect on children's growth. While we find statistical evidence of a quantity/quality tradeoff effect, the biological significance of these results is negligible in early childhood. Our findings help to resolve why quantity/quality studies have had inconsistent results by showing that sibling competition varies with sibling age composition, not just family size, and that biological significance is distinct from statistical significance.

Attention Problems, Inhibitory Control, and Intelligence Index Overlapping Genetic Factors: A Study in 9-, 12-, and 18-Year-Old Twins

OpenAIRE

Polderman, T.J.C.; de Geus, E.J.C.; Hoekstra, R.A.; Bartels, M.; van Leeuwen, M.; Verhulst, F.C.; Posthuma, D.; Boomsma, D.I.

2009-01-01

It is assumed that attention problems (AP) are related to impaired executive functioning. We investigated the association between AP and inhibitory control and tested to what extent the association was due to genetic factors shared with IQ. Data were available from 3 independent samples of 9-, 12-, and 18-year-old twins and their siblings (1,209 participants). AP were assessed with checklists completed by multiple informants. Inhibitory control was measured with the Stroop Color Word Task (St...

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…

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

OpenAIRE

Karin eKeller; Karin eKeller; Larissa Maria Troesch; Alexander eGrob

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...

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…

Simulations of stress-induced twinning and de-twinning: A phase field model

International Nuclear Information System (INIS)

Hu Shenyang; Henager, Chuck H.; Chen Longqing

2010-01-01

Twinning in certain metals or under certain conditions is a major plastic deformation mode. Here we present a phase field model to describe twin formation and evolution in a polycrystalline fcc metal under loading and unloading. The model assumes that twin nucleation, growth and de-twinning is a process of partial dislocation nucleation and slip on successive habit planes. Stacking fault energies, energy pathways (γ surfaces), critical shear stresses for the formation of stacking faults and dislocation core energies are used to construct the thermodynamic model. The simulation results demonstrate that the model is able to predict the nucleation of twins and partial dislocations, as well as the morphology of the twin nuclei, and to reasonably describe twin growth and interaction. The twin microstructures at grain boundaries are in agreement with experimental observation. It was found that de-twinning occurs during unloading in the simulations, however, a strong dependence of twin structure evolution on loading history was observed.

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…

Living with disability. Taking care of siblings

Directory of Open Access Journals (Sweden)

Roberta Caldin

2016-11-01

Full Text Available The birth of a disabled child is a critical event that places all the members of the family in a condition of great vulnerability. When talking about families with a disabled child, attention is usually focused on the parents. Siblings tend to play a marginal role, as shown in the referred literature, in this specific field of investigation. Communicating diagnosis to siblings means involving them in the process of family change, making them active players rather than “spectators” in their own “existential niche”. Communication of diagnosis is a delicate, continuous process that has to be tackled appropriately, using targeted words and educational actions. Children need help in accepting and welcoming their disabled sibling, with all his/her characteristics (and deficits, through a balanced, pondered approach that includes both the dimension of co-development and the acknowledgement of problematic situations.

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.

Conjoined twins – role of imaging and recent advances

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Rishi Philip Mathew

2017-12-01

Full Text Available Introduction: Conjoined twins are identical twins with fused bodies, joined in utero. They are rare complications of monochorionic twinning. The purpose of this study is to describe the various types of conjoined twins, the role of imaging and recent advances aiding in their management. Material and methods: This was a twin institutional study involving 3 cases of conjoined twins diagnosed over a period of 6 years from 2010 to 2015. All the 3 cases were identified antenatally by ultrasound. Only one case was further evaluated by MRI. Results: Three cases of conjoined twins (cephalopagus, thoracopagus and omphalopagus were accurately diagnosed on antenatal ultrasound. After detailed counseling of the parents and obtaining written consent, all the three cases of pregnancy were terminated. Delivery of the viable conjoined twins was achieved without any complications to the mothers, and all the three conjoined twins died after a few minutes. Conclusion: Ultrasound enables an early and accurate diagnosis of conjoined twins, which is vital for obstetric management. MRI is reserved for better tissue characterization. Termination of pregnancy when opted, should be done at an early stage as later stages are fraught with problems. Recent advances, such as 3D printing, may aid in surgical pre-planning, thereby enabling successful surgical separation of conjoined twins.

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…

Laying the ghost of twin paradox

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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.

Twin-twin transfusion syndrome: etiology, severity and rational management

NARCIS (Netherlands)

van Gemert, M. J.; Umur, A.; Tijssen, J. G.; Ross, M. G.

2001-01-01

The twin-twin transfusion syndrome is a serious complication of monochorionic twin pregnancies. Partly as a result of an inadequate understanding of the pathophysiology of the syndrome, there is a lack of consensus in clinical management. We sought to review the available information on the etiology

The early development of infant siblings of children with autism spectrum disorder: Characteristics of sibling interactions

Science.gov (United States)

Warreyn, Petra; Van der Paelt, Sara; Demurie, Ellen; Roeyers, Herbert

2018-01-01

Although sibling interactions play an important role in children’s early development, they are rarely studied in very young children with an older brother or sister with autism spectrum disorder (ASD). This study used a naturalistic, observational method to compare interactions between 18-month-old infants and their older sibling with ASD (n = 22) with a control group of 18-month-old infants and their typically developing (TD) older sibling (n = 29). In addition, role (a)symmetry and the influence of gender were evaluated. Sibling interactions in ASD-dyads were characterized by higher levels of negativity. Although somewhat less pronounced in ASD-dyads, role asymmetry was present in both groups, with the older child taking the dominant position. Finally, siblings pairs with an older sister were characterized by more positive behaviours. Since differences in sibling interactions may alter the developmental trajectories of both siblings, these early relationships should be taken into account in future ASD research and interventions. PMID:29543814

Chronic pain, depression and cardiovascular disease linked through a shared genetic predisposition: Analysis of a family-based cohort and twin study.

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Oliver van Hecke

Full Text Available Depression and chronic pain are the two most important causes of disability (Global Burden of Disease Study 2013. They occur together more frequently than expected and both conditions have been shown to be co-morbid with cardiovascular disease. Although shared socio-demographic risk factors (e.g. gender, deprivation might explain the co-morbidity of these three conditions, we hypothesised that these three long-term, highly prevalent conditions co-occur and may be due to shared familial risk, and/or genetic factors.We employed three different study designs in two independent cohorts, namely Generation Scotland and TwinsUK, having standardised, validated questionnaire data on the three traits of interest. First, we estimated the prevalence and co-occurrence of chronic pain, depression and angina among 24,024 participants of a population-based cohort of extended families (Generation Scotland: Scottish Family Health Study, adjusting for age, gender, education, smoking status, and deprivation. Secondly, we compared the odds of co-morbidity in sibling-pairs with the odds in unrelated individuals for the three conditions in the same cohort. Lastly, examination of similar traits in a sample of female twins (TwinsUK, n = 2,902, adjusting for age and BMI, allowed independent replication of the findings and exploration of the influence of additive genetic (A factors and shared (C and non-shared (E environmental factors predisposing to co-occurring chronic widespread pain (CWP and cardiovascular disease (hypertension, angina, stroke, heart attack, elevated cholesterol, angioplasty or bypass surgery. In the Generation Scotland cohort, individuals with depression were more than twice as likely to have chronic pain as those without depression (adjusted OR 2·64 [95% CI 2·34-2·97]; those with angina were four times more likely to have chronic pain (OR 4·19 [3·64-4·82]; those with depression were twice as likely to have angina (OR 2·20 [1·90-2·54

The mobility of growth twins synthesized by sputtering: Tailoring the twin thickness

International Nuclear Information System (INIS)

Velasco, Leonardo; Hodge, Andrea M.

2016-01-01

The current work presents a protean twin thickness contour zone map that illustrates how the nucleation and the mobility of twin boundaries affects the twin thickness of sputtered films. The twin thickness contour zone map can be used as a versatile guide to synthesize fully nanotwinned films with tailored twin thicknesses in materials with a wide range of stacking fault energies. The nucleation and mobility of twin boundaries was studied in four Cu alloys of different compositions (Cu-6wt.%Al, Cu-4wt.%Al, Cu-2wt.%Al, and Cu-10wt.%Ni), having stacking fault energies ranging from 6 mJ/m 2 to 60 mJ/m 2 . The films were synthesized by magnetron sputtering and characterized by transmission electron microscopy, where the twin thickness varied from 2 nm to 35 nm. Our experimental results show that it is possible to control the twin thickness. Three main mechanisms are explained to describe twin nucleation and twin boundary mobility, which are correlated to the interplay of specific sputtering conditions and the deposition temperature.

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

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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.

Genetic and environmental influences on the comorbidity between depression, panic disorder, agoraphobia and social phobia: A twin study

Science.gov (United States)

Mosing, Miriam A.; Gordon, Scott D.; Medland, Sarah E.; Statham, Dixie J.; Nelson, Elliot C.; Heath, Andrew C.; Martin, Nicholas G.; Wray, Naomi R.

2011-01-01

Background Major depression (MD) and anxiety disorders such as panic disorder (PD), agoraphobia (AG) and social phobia (SP) are heritable and highly comorbid. However, the relative importance of genetic and environmental aetiology of the covariation between these disorders, particularly the relationship between PD and AG is less clear. Methods The present study measured MD, PD and AG in a population sample of 5440 twin pairs and 1245 single twins, about 45% of whom were also scored for SP. Prevalences, within individual comorbidity and twin odds ratios for comorbidity are reported. A behavioural genetic analysis of the four disorders using the classical twin design was conducted. Results Odds ratios for MD, PD, AG, and SP in twins of individuals diagnosed with one of the four disorders were increased. Heritability estimates under a threshold-liability model for MD, PD, AG, and SP respectively were 0.33 (CI:0.30–0.42), 0.38 (CI:0.24–0.55), 0.48 (CI:0.37–0.65) of, and 0.39 (CI:0.16–0.65), with no evidence for any variance explained by the common environment shared by twins. We find that a common genetic factor explains a moderate proportion of variance in these four disorders. The genetic correlation between PD and AG was 0.83. Conclusion MD, PD, AG, and SP strongly co-aggregate within families and common genetic factors explain a moderate proportion of variance in these four disorders. The high genetic correlation between PD and AG and the increased odds ratio for PD and AG in siblings of those with AG without PD suggests a common genetic aetiology for PD and AG. PMID:19750555

My sister's keeper?: genomic research and the identifiability of siblings

Directory of Open Access Journals (Sweden)

Kohane Isaac S

2008-07-01

Full Text Available Abstract Background Genomic sequencing of SNPs is increasingly prevalent, though the amount of familial information these data contain has not been quantified. Methods We provide a framework for measuring the risk to siblings of a patient's SNP genotype disclosure, and demonstrate that sibling SNP genotypes can be inferred with substantial accuracy. Results Extending this inference technique, we determine that a very low number of matches at commonly varying SNPs is sufficient to confirm sib-ship, demonstrating that published sequence data can reliably be used to derive sibling identities. Using HapMap trio data, at SNPs where one child is homozygotic major, with a minor allele frequency ≤ 0.20, (N = 452684, 65.1% we achieve 91.9% inference accuracy for sibling genotypes. Conclusion These findings demonstrate that substantial discrimination and privacy risks arise from use of inferred familial genomic data.

Rearing Environmental Influences on Religiousness: An Investigation of Adolescent Adoptees.

Science.gov (United States)

Koenig, Laura B; McGue, Matt; Iacono, William G

2009-10-01

Religiousness is widely considered to be a culturally transmitted trait. However, twin studies suggest that religiousness is genetically influenced in adulthood, although largely environmentally influenced in childhood/adolescence. We examined genetic and environmental influences on a self-report measure of religiousness in a sample consisting of 284 adoptive families (two adopted adolescent siblings and their rearing parents); 208 biological families (two full biological adolescent siblings and their parents); and 124 mixed families (one adopted and one biological adolescent sibling and their parents). A sibling-family model was fit to the data to estimate genetic, shared environmental, and nonshared environmental effects on religiousness, as well as cultural transmission and assortative mating effects. Religiousness showed little evidence of heritability and large environmental effects, which did not vary significantly by gender. This finding is consistent with the results of twin studies of religiousness in adolescent and preadolescent samples.

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. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Siblings of prepubesecent anorexic children].

Science.gov (United States)

Noël, L; de Maynadier, L

2014-10-01

As professionals working in a specialised unit for prepubescent anorexic children, we are very often concerned with the siblings of our young patients who are daily faced with anorexia nervosa. Although it is an undeniable subject of prevention, research on the topic remains scarce. Based on our clinical experience, this article thus proposes to give a few landmarks to health professionals likely to support these siblings in order to prevent anxious and depressive disorders as well as eating disorders. If guided, supported and informed on anorexia nervosa, siblings can adopt adequate coping strategies when confronted to their sibling's anorexic cognitions and behaviours. We also encourage parents to pay close attention to the needs of their other children, especially to remain receptive to the youngest ones or, if unavailable to find adult carers (grandparents, family, friends). We also guide these children, who are eager to help their anorexic sibling, to remain in a brotherly role. Siblings must be informed about anorexia nervosa. Such information enables them to have a better understanding of their sister's thoughts and attitudes. It also leads to a better understanding of the reasons why anorexia has such a significant impact on family routine, among other things by reducing parental availability. Beyond enabling siblings to adopt adequate coping strategies, such provision of support also contributes to the prevention of mental illness and the maintenance of adequate sibling and family relationships. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Risk of maltreatment for siblings: Factors associated with similar and different childhood experiences in a dyadic sample of adult siblings.

Science.gov (United States)

Witte, Susanne; Fegert, Jörg M; Walper, Sabine

2018-02-01

Siblings share the same environment and thus potentially a substantial number of risk factors for child maltreatment. Furthermore, the number of siblings and the sibling constellation itself might pose a risk for child maltreatment. Little is known about the likelihood that more than one child in a family is maltreated and which factors increase the risk. This study sought to investigate similarities and differences in maltreatment in siblings and risk factors associated with the maltreatment of more than one child from the same family. Data on maltreatment during childhood and adolescence, family background, and sibling constellation were collected from 870 pairs of siblings. In the dyadic analyses, siblings reported similar maltreatment experiences, especially when any type of maltreatment was considered. Parents' mental health problems were significant predictors for maltreatment of at least one sibling. Father's mental health problems were predictive of maltreatment of both or only the younger sibling, mother's mental health problems of both or only the older sibling. Closeness in age and same gender of siblings did not emerge as a consistent predictor. The increasing number of siblings was a risk factor for any type of maltreatment of both siblings. The results highlight the need for preventive measures for families with a large number of children and with parents with mental health problems as well as a repeated risk assessment of all siblings in a family when one sibling was maltreated. Copyright © 2017 Elsevier Ltd. All rights reserved.

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 me...

Effect of co-twin gender on neurodevelopmental symptoms: a twin register study.

Science.gov (United States)

Eriksson, Jonna Maria; Lundström, Sebastian; Lichtenstein, Paul; Bejerot, Susanne; Eriksson, Elias

2016-01-01

Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are neurodevelopmental disorders thought to have both genetic and environmental causes. It has been hypothesized that exposure to elevated levels of prenatal testosterone is associated with elevated traits of ASD and ADHD. Assuming that testosterone levels from a dizygotic male twin fetus may lead to enhanced testosterone exposure of its co-twins, we aimed to test the prenatal testosterone hypothesis by comparing same-sex with opposite-sex dizygotic twins with respect to neurodevelopmental symptoms. Neuropsychiatric traits were assessed in a population-based twin cohort from the Child and Adolescent Twin Study in Sweden (CATSS). Parental interviews were conducted for 16,312 dizygotic twins, 9 and 12 years old, with the Autism-Tics, ADHD, and other Comorbidities inventory (A-TAC). Girls with a female co-twin had an increased risk of reaching the cut-off score for ADHD compared with girls with a male co-twin. Both boys and girls with a female co-twin displayed a larger number of traits related to attention deficit and repetitive and stereotyped behaviors than those with a male twin. In girls, this also extended to social interaction and the combined measures for ASD and ADHD, however, with small effect sizes. Our results are reverse to what would have been expected from the prenatal testosterone hypothesis but consistent with a previous study of ASD and ADHD traits in dizygotic twins. The seemingly protective effect for girls of having a twin brother may be an effect of parent report bias, but may also be an unexpected effect of sharing the intrauterine environment with a male co-twin.

My older sibling was drunk - younger siblings' drunkenness in relation to parental monitoring and the parent-adolescent relationship.

Science.gov (United States)

Gossrau-Breen, Diana; Kuntsche, Emmanuel; Gmel, Gerhard

2010-10-01

This study explored the links between having older siblings who get drunk, satisfaction with the parent-adolescent relationship, parental monitoring, and adolescents' risky drinking. Regression models were conducted based on a national representative sample of 3725 8th to 10th graders in Switzerland (mean age 15.0, SD = .93) who indicated having older siblings. Results showed that both parental factors and older siblings' drinking behaviour shape younger siblings' frequency of risky drinking. Parental monitoring showed a linear dose-response relationship, and siblings' influence had an additive effect. There was a non-linear interaction effect between parent-adolescent relationship and older sibling's drunkenness. The findings suggest that, apart from avoiding an increasingly unsatisfactory relationship with their children, parental monitoring appears to be important in preventing risky drinking by their younger children, even if the older sibling drinks in such a way. However, a satisfying relationship with parents does not seem to be sufficient to counterbalance older siblings' influence.

Late language emergence in 24-month-old twins: heritable and increased risk for late language emergence in twins.

Science.gov (United States)

Rice, Mabel L; Zubrick, Stephen R; Taylor, Catherine L; Gayán, Javier; Bontempo, Daniel E

2014-06-01

This study investigated the etiology of late language emergence (LLE) in 24-month-old twins, considering possible twinning, zygosity, gender, and heritability effects for vocabulary and grammar phenotypes. A population-based sample of 473 twin pairs participated. Multilevel modeling estimated means and variances of vocabulary and grammar phenotypes, controlling for familiality. Heritability was estimated with DeFries-Fulker regression and variance components models to determine effects of heritability, shared environment, and nonshared environment. Twins had lower average language scores than norms for single-born children, with lower average performance for monozygotic than dizygotic twins and for boys than girls, although gender and zygosity did not interact. Gender did not predict LLE. Significant heritability was detected for vocabulary (0.26) and grammar phenotypes (0.52 and 0.43 for boys and girls, respectively) in the full sample and in the sample selected for LLE (0.42 and 0.44). LLE and the appearance of Word Combinations were also significantly heritable (0.22-0.23). The findings revealed an increased likelihood of LLE in twin toddlers compared with single-born children that is modulated by zygosity and gender differences. Heritability estimates are consistent with previous research for vocabulary and add further suggestion of heritable differences in early grammar acquisition.

Genetic and environmental influences on the co-morbidity between depression, panic disorder, agoraphobia, and social phobia: a twin study.

Science.gov (United States)

Mosing, Miriam A; Gordon, Scott D; Medland, Sarah E; Statham, Dixie J; Nelson, Elliot C; Heath, Andrew C; Martin, Nicholas G; Wray, Naomi R

2009-01-01

Major depression (MD) and anxiety disorders such as panic disorder (PD), agoraphobia (AG), and social phobia (SP) are heritable and highly co-morbid. However, the relative importance of genetic and environmental etiology of the covariation between these disorders, particularly the relationship between PD and AG, is less clear. This study measured MD, PD, and AG in a population sample of 5,440 twin pairs and 1,245 single twins, about 45% of whom were also scored for SP. Prevalences, within individual co-morbidity and twin odds ratios for co-morbidity, are reported. A behavioral genetic analysis of the four disorders using the classical twin design was conducted. Odds ratios for MD, PD, AG, and SP in twins of individuals diagnosed with one of the four disorders were increased. Heritability estimates under a threshold-liability model for MD, PD, AG, and SP respectively were .33 (CI: 0.30-0.42), .38 (CI: 0.24-0.55), .48 (CI: 0.37-0.65), and .39 (CI: 0.16-0.65), with no evidence for any variance explained by the common environment shared by twins. We find that a common genetic factor explains a moderate proportion of variance in these four disorders. The genetic correlation between PD and AG was .83. MD, PD, AG, and SP strongly co-aggregate within families and common genetic factors explain a moderate proportion of variance in these four disorders. The high genetic correlation between PD and AG and the increased odds ratio for PD and AG in siblings of those with AG without PD suggests a common genetic etiology for PD and AG.

Weighted gene co-expression network analysis of expression data of monozygotic twins identifies specific modules and hub genes related to BMI

DEFF Research Database (Denmark)

Wang, Weijing; Jiang, Wenjie; Hou, Lin

2017-01-01

BACKGROUND: The therapeutic management of obesity is challenging, hence further elucidating the underlying mechanisms of obesity development and identifying new diagnostic biomarkers and therapeutic targets are urgent and necessary. Here, we performed differential gene expression analysis......) were with a trend of up-regulation in twins with higher BMI when compared to their siblings. Categories of positive regulation of nitric-oxide synthase biosynthetic process, positive regulation of NF-kappa B import into nucleus, and peroxidase activity were significantly enriched within GO database...

Intergenerational Solidarity and Support Between Adult Siblings

NARCIS (Netherlands)

Voorpostel, Marieke; Blieszner, Rosemary

2008-01-01

Using a Dutch national sample containing 1,259 triads (two siblings, one parent), we examined whether practical support and emotional support between siblings are enhanced by intergenerational solidarity and how this differs for brothers and sisters. Sibling support was affected by sibling dyad

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.

Binomial outcomes in dataset with some clusters of size two: can the dependence of twins be accounted for? A simulation study comparing the reliability of statistical methods based on a dataset of preterm infants.

Science.gov (United States)

Sauzet, Odile; Peacock, Janet L

2017-07-20

The analysis of perinatal outcomes often involves datasets with some multiple births. These are datasets mostly formed of independent observations and a limited number of clusters of size two (twins) and maybe of size three or more. This non-independence needs to be accounted for in the statistical analysis. Using simulated data based on a dataset of preterm infants we have previously investigated the performance of several approaches to the analysis of continuous outcomes in the presence of some clusters of size two. Mixed models have been developed for binomial outcomes but very little is known about their reliability when only a limited number of small clusters are present. Using simulated data based on a dataset of preterm infants we investigated the performance of several approaches to the analysis of binomial outcomes in the presence of some clusters of size two. Logistic models, several methods of estimation for the logistic random intercept models and generalised estimating equations were compared. The presence of even a small percentage of twins means that a logistic regression model will underestimate all parameters but a logistic random intercept model fails to estimate the correlation between siblings if the percentage of twins is too small and will provide similar estimates to logistic regression. The method which seems to provide the best balance between estimation of the standard error and the parameter for any percentage of twins is the generalised estimating equations. This study has shown that the number of covariates or the level two variance do not necessarily affect the performance of the various methods used to analyse datasets containing twins but when the percentage of small clusters is too small, mixed models cannot capture the dependence between siblings.

Perceptions of emotion expression and sibling-parent emotion communication in Latino and non-Latino white siblings of children with intellectual disabilities.

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Long, Kristin A; Lobato, Debra; Kao, Barbara; Plante, Wendy; Grullón, Edicta; Cheas, Lydia; Houck, Christopher; Seifer, Ronald

2013-06-01

Examine general emotion expression and sibling-parent emotion communication among Latino and non-Latino white (NLW) siblings of children with intellectual disabilities (ID) and matched comparisons. 200 siblings (ages 8-15 years) completed the newly developed Sibling-Parent Emotion Communication Scale and existing measures of general emotion expression and psychosocial functioning. Preliminary analyses evaluated scale psychometrics across ethnicity. Structure and internal consistency of the emotion expression and communication measures differed by respondent ethnicity. Latino siblings endorsed more general emotion expression problems and marginally lower sibling-parent emotion communication than NLW siblings. Siblings of children with ID reported marginally more general emotion expression problems than comparisons. Emotion expression problems and lower sibling-parent emotion communication predicted more internalizing and somatic symptoms and poorer personal adjustment, regardless of ID status. Siblings of children with ID endorsed poorer personal adjustment. Cultural differences in emotion expression and communication may increase Latino siblings' risk for emotional adjustment difficulties.

Infant siblings and the investigation of autism risk factors

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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.

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

Examining the role of communication on sibling relationship quality and interaction for sibling pairs with and without a developmental disability.

Science.gov (United States)

Smith, Ashlyn L; Romski, Maryann; Sevcik, Rose A

2013-09-01

This study examined communication interaction patterns when one sibling had a developmental disability as well as the role of communication skills in sibling relationship quality. Thirty sibling dyads were categorized into one of three communication status groups: emerging, context-dependent, and independent communicators. Independent communicators and their siblings did not differ in terms of syntactic complexity but typically developing siblings dominated the interaction and exhibited greater lexical diversity regardless of communication status. Communication status did not impact the warmth/closeness, rivalry, or conflict in the sibling relationship, but siblings of independent communicators engaged in the greatest amount of helping and managing behaviors. These results represent a first step in understanding the role of communication skills in the sibling relationship for families of children with disabilities.

Shared-Environmental Contributions to High Cognitive Ability

OpenAIRE

Kirkpatrick, Robert M.; McGue, Matt; Iacono, William G.

2009-01-01

Using a combined sample of adolescent twins, biological siblings, and adoptive siblings, we estimated and compared the differential shared-environmentality for high cognitive ability and the shared-environmental variance for the full range of ability during adolescence. Estimates obtained via multiple methods were in the neighborhood of 0.20, and suggest a modest effect of the shared environment on both high and full-range ability. We then examined the association of ability with three measur...

Number of Siblings, Sibling Spacing, Sex, and Birth Order: Their Effects on Perceived Parent-Adolescent Relationships.

Science.gov (United States)

Kidwell, Jeannie S.

1981-01-01

Examined the effect of the sibling structures of number and spacing, sex composition, and birth order on adolescents' perceptions of the power and support dimensions of parental behavior. Results suggest that research focusing on birth order must control for number of siblings, spacing, and sex composition of siblings. (Author)

Estimating twin concordance for bivariate competing risks twin data

DEFF Research Database (Denmark)

Scheike, Thomas; Holst, Klaus K.; Hjelmborg, Jacob B.

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 experience...... 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...... 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...

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…

Childhood Sibling Relationships of Eminent Canadian Women.

Science.gov (United States)

Yewchuk, Carolyn R.; Schlosser, Grace A.

1996-01-01

This study compared differences between 72 eminent Canadian women who reported close sibling relationships and 72 similar women who reported no close sibling relationships. Those with close siblings expressed their responsibility within the relationship and rivalry within the sibship. Those not close to siblings often blamed this on age…

Modeling acardiac twin pregnancies

NARCIS (Netherlands)

de Groot, Rosa; van den Wijngaard, Jeroen P. H. M.; Umur, Asli; Beek, Johan F.; Nikkels, Peter G. J.; van Gemert, Martin J. C.

2007-01-01

Acardiac twin pregnancies are a rare but severe complication of monochorionic twinning, where the acardiac twin lacks cardiac function but nevertheless grows during pregnancy because it is perfused by the pump twin through a set of placental arterioarterial and venovenous anastomoses. Because the

Screening and Invasive Testing in Twins

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Giovanni Monni

2014-07-01

Full Text Available Prenatal screening and testing for trisomy 21 in twin pregnancies poses a number of challenges: the exact estimate of the a priori risk of trisomy 21, the choice of prenatal screening test and/or invasive techniques to employ for the diagnosis and the impact of the result on the options of treatment in case of discordant results within a twin pair or among multiples. These different aspects are discussed below while recognizing that many issues remain unresolved.

Sibling Influence on Mexican-Origin Adolescents’ Deviant and Sexual Risk Behaviors: The Role of Sibling Modeling

Science.gov (United States)

Whiteman, Shawn D.; Zeiders, Katharine H.; Killoren, Sarah E.; Rodriguez, Sue Annie; Updegraff, Kimberly A.

2013-01-01

Purpose A growing body of research indicates that siblings uniquely influence each other’s health risk behaviors during adolescence and young adulthood. Mechanisms underlying these associations, however, are largely unknown because they are rarely tested directly. The present study addressed this gap by examining the role of sibling modeling in explaining changes in Mexican-origin youths’ deviant and sexual risk behaviors over time. Methods The sample included 380 Mexican-origin siblings (older sibling age: M = 21.18, SD = 1.59; younger sibling age: M = 18.19, SD = .46) from (N = 190) families. Participants provided self-reports of their sibling relationship qualities, including modeling, as well as their engagement in deviant and sexual risk taking behaviors in two home interviews across a two-year span. Results A series of residualized regression models revealed that younger siblings’ perceptions of modeling moderated the links between older siblings’ deviant and sexual risk behaviors and younger siblings’ subsequent behaviors in those same domains. Specifically, high levels of modeling predicted stronger associations between older siblings’ earlier and younger siblings’ later risk behaviors controlling for younger siblings’ earlier behaviors as well as variables that have been used as proxies for social learning in previous research. Conclusions Social learning mechanisms, especially modeling, are salient processes through which older siblings transmit norms and expectations regarding participation in health risk behaviors. Future research should continue to explore the ways in which siblings influence each other because such processes are emerging targets for intervention and prevention. PMID:24287013

Mechanisms of Sibling Socialization in Normative Family Development

Science.gov (United States)

Whiteman, Shawn D.; Becerra, Julia M.; Killoren, Sarah E.

2009-01-01

Siblings are important sources of social influence throughout childhood and adolescence. Nevertheless, the processes by which siblings influence one another remain relatively unexplored. We highlight two theories of sibling influence--sibling deidentification and social learning--that offer insights as to how and why siblings develop similar and…

Sibling Rivalry: A Parent Education Perspective.

Science.gov (United States)

Calladine, Carole E.

1983-01-01

Identifies three styles of sibling rivalry and three parent leadership styles, discussing parental mediation of sibling disputes through contracting and providing examples of group discipline techniques that facilitate development of less negative forms of rivalry and that support positive sibling bonding. (RH)

Why do identical twins differ in personality: shared environment reconsidered.

Science.gov (United States)

Torgersen, Anne Mari; Janson, Harald

2002-02-01

While heritability studies show that most of the variance in adult personality can be attributed to genetic or so-called nonshared environmental influence, this does not mean that shared events lack importance for the development of later personality differences. We studied the relationship between Big Five personality differences in monozygotic (MZ) twins at age 29, and life stressors at age 6 to 15, using prospective data from 26 MZ pairs studied from birth onwards. A positive significant correlation was found between stressors in childhood and early adolescence, and intrapair personality differences in Agreeableness, Openness, Conscientiousness, and five-factor profiles. We note that the effects of shared events are labeled "nonshared" environment when the effect is to make siblings more different. Case examples illustrate the relationship between stress and personality differences, and provide hypotheses for further studies in larger samples.

Adolescents' experiences of having a stillborn half-sibling.

Science.gov (United States)

Avelin, Pernilla; Gyllenswärd, Göran; Erlandsson, Kerstin; Rådestad, Ingela

2014-01-01

Although there is an increasing interest in siblings' experiences of loss and grief there is limited knowledge of adolescent's own perspectives, especially in a unique situation as after stillbirth in a reconstituted family. The authors interviewed 13 bereaved adolescents. They were sad that their family was not the same and expressed feelings of being inside family grief, yet outside, because they did not have full access in their reconstituted family. An implication of present findings is that it is important to include all the members of the family in the grieving process, even half-siblings of the deceased child.

Acral peeling skin syndrome in two East-African siblings: case report

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Kiprono Samson K

2012-03-01

Full Text Available Abstract Background Acral peeling skin syndrome is a rare autosomal recessive genodermatosis due to a missense mutation in transglutaminase 5. The skin peeling occurs at the separation of the stratum corneum from the stratum granulosum. Case presentation We present a case of two siblings who developed continuous peeling of the palms and soles from the first year of life. This peeling was more severe on the soles than palms and on younger sibling than elder sibling. Peeling is worsened by occlusion and sweating. Conclusions Sporadic cases of Acral Peeling Skin Syndrome occur in African population. There is variability in time of presentation and clinical severity even within families.

Thyroid aplasia in male sibling of heterozygotic twins born to the hyperthyroid mother treated with propylthiouracil during pregnancy (case report).

Science.gov (United States)

Almarzouki, A A

2012-01-01

A 30-year-old pregnant female was diagnosed to have thyrotoxicosis (TSH= 0.005 µU/ml) at 13th week of gestation. Propylthiouracil (PTU; 200 mg daily) was prescribed to her and four weekly follow ups by the endocrinologist and obstetrician were ensured. At each examination TSH, FT4 and FT3 levels were normal and she became symptom free. Repeated ultrasound examination throughout the pregnancy did not reveal any fetal abnormality. The lady normally delivered heterozygotic twins. Umbilical cord blood of the baby boy twin showed a high TSH (541 µU/ml; reference range 0.270 - 4.20 μU/ml). He was started on thyroxine therapy (50 µg once daily). Ultrasound reported the absence of the thyroid gland. One month later TSH was within normal range and thyroxine dose was adjusted to 25 µg once daily. Repeated ultrasound confirmed the absence of thyroid gland. TSH was repeatedly normal. The boy is currently doing well on thyroxine replacement therapy. The other non-identical twin was a healthy girl with normal thyroid function tests and always thereafter. This case report suggested that PTU could be a hazardous drug to the fetus, since the mother gave birth to a baby with thyroid aplasia. PTU, Thyroid aplasia, Thyrotoxicosis, TSH.

Full polarization measurement of SR emitted from twin helical undulators using Sc/Cr multilayers at 398.6 eV

International Nuclear Information System (INIS)

Hirono, T.; Kimura, H.; Muro, T.; Saitoh, Y.; Ishikawa, T.

2004-01-01

Full text: Many of scientific measurements utilizing the polarization characteristics such as MCD are vigorously studied in soft x-ray region. To obtain polarization state precisely is important to study physical phenomena quantitatively. For example, using information of accurate polarization state of probe beam we are able to discuss not only a structure of spectrum but also absolute value of measured data. We carried out the full polarization measurements at BL25SU in SPring-8. The measurements were performed for synchrotron radiation (SR) beam of 398.6 eV emitted from twin helical undulators. All parameters of polarization state of the beam were determined with phase shifting transmission multilayer and polarizing reflection multilayer. The phase shifter was a newly developed Sc/Cr multilayer and was evaluated as a quarter-wave plate. In the presentation, we will report the full polarization measurement of circularly polarized light using the quarter-wave plate

'Adoption' by maternal siblings in wild chimpanzees.

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Catherine Hobaiter

Full Text Available The adoption of unrelated orphaned infants is something chimpanzees and humans have in common. Providing parental care has fitness implications for both the adopter and orphan, and cases of adoption have thus been cited as evidence for a shared origin of an altruistic behaviour. We provide new data on adoptions in the free-living Sonso chimpanzee community in Uganda, together with an analysis of published data from other long-term field sites. As a default pattern, we find that orphan chimpanzees do not become adopted by adult group members but wherever possible associate with each other, usually as maternal sibling pairs. This occurs even if both partners are still immature, with older individuals effectively becoming 'child household heads'. Adoption of orphans by unrelated individuals does occur but usually only if no maternal siblings or other relatives are present and only after significant delays. In conclusion, following the loss of their mother, orphaned chimpanzees preferentially associate along pre-existing social bonds, which are typically strongest amongst maternal siblings.

Body Talk: Siblings' Use of Positive and Negative Body Self-Disclosure and Associations with Sibling Relationship Quality and Body-Esteem.

Science.gov (United States)

Greer, Kelly Bassett; Campione-Barr, Nicole; Lindell, Anna K

2015-08-01

The sibling relationship has been deemed the quintessential "love-hate relationship." Sibling relationships have also been found to have both positive and negative impacts on the adjustment of youth. Unlike previous research, however, the present study examined the associations between siblings' positive and negative body-related disclosures with relationship quality and body-esteem. Additionally, ordinal position, individual sex, and sibling sex composition were tested as moderators. Participants included 101 predominantly White and middle class adolescent sibling dyads (54 % female adolescents, with relatively equal sibling gender compositions). Older siblings were, on average, 16.46 (SD = 1.35) years old with younger siblings an average of 13.67 (SD = 1.56) years. Adolescents completed questionnaires and data were analyzed using Actor-Partner Interdependence Modeling, which focused on disclosure to and from dyad members. In general, sibling body-related disclosure was positive for the quality of the sibling relationship, regardless of the valance of disclosure. Also, adolescents' body esteem was greater when adolescents reported disclosing (i.e., actor-effects) about positive or negative body issues to their siblings (particularly for females). Conversely, when adolescents received positive or negative body-related disclosures from their siblings (i.e., partner-effects), adolescents reported lower levels of body esteem (particularly for girls and younger siblings). Thus, the impact of body-related disclosure on adolescents' feelings of body esteem appear to be associated more with whether they are the discloser or the one being disclosed to, while the impact on the quality of the relationship has simply more to do with whether or not they are generally disclosing to one another.

Twinning in muskox and the cytogenetic investigation of a freemartin

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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.

Executive function in adolescents with PKU and their siblings: Associations with biochemistry

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R. Sharman

2015-09-01

Full Text Available Previous research shows consistent and marked executive function impairment in children with early and continuously treated phenylketonuria. This between groups analysis (phenylketonuria group vs sibling controls found no significant differences in executive function (although adolescents with phenylketonuria performed slightly worse than their siblings. Biochemical relationships with executive function were confined to long-term measures of high phenylalanine:tyrosine ratio exposure, as well as tyrosine exposure independent of phenylalanine. This study suggests that early and continuously treated PKU results in non-significant EF differences (compared to siblings, although the influence of long-term exposure to poorer metabolic control is still evident.

Theory of mind in children with and without autism spectrum disorder: Associations with the sibling constellation.

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Matthews, Nicole L; Goldberg, Wendy A

2018-04-01

The two prior studies that have examined associations between the sibling constellation and theory of mind in autism spectrum disorder yielded discrepant findings. Thus, efforts to better understand the sibling-theory of mind link in autism spectrum disorder are necessary. This study examined a sample of prekindergarten- and kindergarten-aged (i.e. 4-6 years) typically developing children ( n = 39) and verbal children with autism spectrum disorder ( n = 61). Sibling presence, number of siblings, and having younger and older siblings were positively associated with theory of mind in typically developing children, but not in the full sample of children with autism spectrum disorder. However, in the subgroup of children with autism spectrum disorder without sibling recurrence, the presence of at least one older sibling was positively associated with theory of mind. Findings expand previous limited research on the sibling-theory of mind link in children with autism spectrum disorder by demonstrating a potential difference in the influence of the sibling constellation between children from simplex and multiplex families.

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.

2015-01-01

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 range of theoretical perspectives in an effort to illuminate the mechanisms underlying sibling relationship experiences and their adjustment implications. Our review suggests new directions for research to test theoretically-grounded hypotheses about how sibling relationships develop and are linked to individual adjustment. In addition, we consider how identifying underlying bio-psycho-social processes can aid in the development of interventions to promote warm and involved sibling relationships and positive youth development. PMID:26476737

At issue: siblings of patients with schizophrenia: sibling bond, coping patterns, and fear of possible schizophrenia heredity.

Science.gov (United States)

Stålberg, Gabriella; Ekerwald, Hedvig; Hultman, Christina M

2004-01-01

Siblings of schizophrenia patients are from the patient's perspective important support providers, but most studies on family burden have focused on the parental role. This study aims to develop a detailed analysis of the psychological aspects of having a sibling with schizophrenia. We did a qualitative study with audiotaped semistructured interviews of 16 siblings. The reliability of the inductive categorization of data was high. A unifying theme appeared to be an emotional sibling bond characterized by feelings of love, sorrow, anger, envy, guilt, and shame. The major categories linked to coping with the situation were avoidance, isolation, normalization, caregiving, and grieving. A third major theme consisted of a fear of possible schizophrenia heredity. The siblings described concerns about the impact of a family history of psychiatric illness, a fear of becoming mentally ill, and reflections about "bad genes." Our findings support earlier findings of coping patterns but complement them by providing a model that includes awareness of genetic vulnerability as an important part of siblings' subjective burden.

The nature of pseudo-twinning modes on the basis of a twin classification scheme

International Nuclear Information System (INIS)

Singh, Jung B.; Sundararaman, M.; Krishnan, M.

2011-01-01

Pseudo-twins can form in ordered structures under high stress conditions. These twins are defined by lattice sites that are at twin positions but are incorrectly occupied by different species of atoms. The present note discusses if it is possible to further classify pseudo-twins into different modes based on the nature of associated twinning elements.

Personality traits and sibling relationships in emerging adults.

Science.gov (United States)

Lanthier, Richard P

2007-04-01

Associations between the Big Five personality traits of siblings and the quality of sibling relationships were examined in a sample of 115 college students and one of their older siblings. Big Five traits, as assessed by Goldberg's 100 adjective markers, predicted a large amount of the variability in sibling Warmth and Conflict. Agreeableness was the most consistent predictor of positive sibling outcomes.

Sibling Gender Composition and Preferences for STEM Education

DEFF Research Database (Denmark)

Brenøe, Anne Ardila

2017-01-01

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......-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......This paper studies how sibling gender composition affects preferences for education within Science, Technology, Engineering, and Mathematics (STEM). To identify the causal effect of sibling gender, I focus on a sample of firstborn children who all have a younger biological sibling. The randomness...

Juvenile greylag geese (Anser anser discriminate between individual siblings.

Directory of Open Access Journals (Sweden)

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.

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…

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

Twin RSA

OpenAIRE

Lenstra, Arjen K.; Weger, De; Benjamin, M. M.

2005-01-01

We introduce Twin RSA, pairs of RSA moduli (n, n+ 2), and formulate several questions related to it. Our main questions are: is Twin RSA secure, and what is it good for? © Springer-Verlag Berlin Heidelberg 2005.

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.

Genetic questions for environmental studies. Differential parenting and psychopathology in adolescence.

Science.gov (United States)

Reiss, D; Hetherington, E M; Plomin, R; Howe, G W; Simmens, S J; Henderson, S H; O'Connor, T J; Bussell, D A; Anderson, E R; Law, T

1995-11-01

Recent genetic evidence suggests that the most important environmental influences on normal and pathologic development are those that are not shared by siblings in the same family. We sought to determine the relationship between differences in parenting styles and depressive symptoms and antisocial behavior in adolescence, and to compare the influence of these nonshared experiences with genetic influences. We studied 708 families with at least two same-sexed adolescent siblings who were monozygotic twins (93 families), dizygotic twins (99 families), ordinary siblings (95 families), full siblings in step families (181 families), half siblings in step families (110 families), and genetically unrelated siblings in step families (130 families). Data on parenting style were collected by questionnaire and by video recording of interaction between parents and children. Almost 60% of variance in adolescent antisocial behavior and 37% of variance in depressive symptoms could be accounted for by conflictual and negative parental behavior directed specifically at the adolescent. In contrast, when a parent directed harsh, aggressive, explosive, and inconsistent parenting toward the sibling, we found less psychopathologic outcome in the adolescent. Parenting behavior directed specifically at each child in the family is a major correlate of symptoms in adolescents. Furthermore, harsh parental behavior directed at a sibling may have protective effects for adolescents, a phenomenon we call the "siblin barricade."

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…

Sports pairs: insights on athletic talent; research reviews: twins with leukemia; parents and twins.

Science.gov (United States)

Segal, Nancy L

2007-06-01

Twin research exploring genetic and environmental influences on athletic interests and talents is reviewed. Illustrative examples of twin athletes representing a variety of sports activities are presented. This is followed by an overview of twin studies offering critical insights into the onset and progress of leukemia. In the last section, timely events involving twins and parents of twins will be described--each case provides a new look at an old question.

Twin edge colorings of certain square graphs and product graphs

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R Rajarajachozhan

2016-04-01

Full Text Available A twin edge $k\\!$-coloring of a graph $G$ is a proper edge $k$-coloring of $G$ with the elements of $\\mathbb{Z}_k$ so that the induced vertex $k$-coloring, in which the color of a vertex $v$ in $G$ is the sum in $\\mathbb{Z}_k$ of the colors of the edges incident with $v,$ is a proper vertex $k\\!$-coloring. The minimum $k$ for which $G$ has a twin edge $k\\!$-coloring is called the twin chromatic index of $G.$ Twin chromatic index of the square $P_n^2,$ $n\\ge 4,$ and the square $C_n^2,$ $n\\ge 6,$ are determined. In fact, the twin chromatic index of the square $C_7^2$ is $\\Delta+2,$ where $\\Delta$ is the maximum degree. Twin chromatic index of $C_m\\,\\Box\\,P_n$ is determined, where $\\Box$ denotes the Cartesian product. $C_r$ and $P_r$ are, respectively, the cycle, and the path on $r$ vertices each.

Reframing Paul’s sibling language in light of Jewish epistolary forms of address

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Kyu Seop Kim

2015-06-01

Full Text Available Recent scholars focus mainly on Paul’s use of ‘brothers (and sisters’ or ‘brother (and sister’ in Greco-Roman epistolary conventions and cultural backdrops. However, Jewish dimensions (particularly ethnic dimensions of Paul’s sibling language still remain unexplored in current scholarship. Furthermore, scholars have not drawn much attention to how Jewish letter writers use sibling terms in their letters. This article offers a new interpretation on Paul’s sibling language in light of its Jewish usage. We should note that Jewish letter writers did not address their Gentile letter recipients as ‘brother(s’. However, Paul did call his recipients ‘brothers’. It is unlikely that Paul employed sibling language without being aware of its common Jewish usage. The author proposes that Paul’s sibling language is used in the context of an ethnic insider designation (shared ethnicity, and that ascribing the title of brother to believers including Gentiles signals the re-definition of the family of Abraham.

The Brazilian Twin Registry.

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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.

Twin Loss: Implications for Counselors Working with Surviving Twins.(practice & Theory)

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Withrow, Rebecca; Schwiebert, Valerie L.

2005-01-01

Multiple births are becoming increasingly prevalent due to the use of fertility drugs and women choosing to wait until later life to conceive. With the growth in the twin population, little research has been done to investigate the effects on the grief process when 1 twin dies. Counselors must understand the unique experience of twins to formulate…

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

quantitative scale and thus can be assessed in affected and unaffected individuals. Continuous measures increase the statistical power to detect genetic effects (Neale et al., 1994), and allow studies to be designed to collect data from informative subjects such as extreme concordant or discordant pairs....... 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....... 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...

Mechanisms of sibling socialization in normative family development.

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Whiteman, Shawn D; Becerra, Julia M; Killoren, Sarah E

2009-01-01

Siblings are important sources of social influence throughout childhood and adolescence. Nevertheless, the processes by which siblings influence one another remain relatively unexplored. We highlight two theories of sibling influence-sibling deidentification and social learning-that offer insights as to how and why siblings develop similar and different attributes, attitudes, and behaviors. Recognizing the need to move past post hoc explanations, we suggest several directions for how these two influence processes can be measured directly in future work. Research on sibling influence also can be improved by integrating these theories and attending to their domains of influence.

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

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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.

Attachment representations, parental differential treatment and sibling relationships.

OpenAIRE

Goodman, E.

2005-01-01

The purpose of this review is to examine the literature on siblings and sibling relationships. To outline the importance of this under-researched field the review details the link between sibling relationship quality and individual psychosocial outcome. Initial research into the area started with investigations of the influence of structural variables and temperament on sibling relationship quality but found that they explained only a small proportion of the variance in sibling relationship q...

LAYOUT of the PASSENGER twin-fuselage AIRPLANE FOR LOCAL LINES

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V. G. Gusev

2015-01-01

Full Text Available The article shows the peculiarities and disadvantages of the classical single-fuselage configuration aircraft for local lines. It also provides an overview of the twin-fuselage configuration aircraft. A version of the twin-fuselage passenger aircraft is offered and the ground of its advantages is given.

Needle twins and right-angled twins in minerals: comparison between experiment and theory

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Salje, E.K.H.; Buckley, A.; Van Tendeloo, G.; Ishibashi, Y.; Nord, G.L.

1998-01-01

Transformation twinning in minerals forms isolated twin walls, intesecting walls with corner junctions, and wedge-shaped twins as elements of hierarchical patterns. When cut perpendicular to the twin walls, the twins have characteristic shapes, right-angled and needle-shaped wall traces, which can be observed by transmission electron microscopy or by optical microscopy. Theoretical geometries of wall shapes recently derived for strain-related systems should hold for most displacive and order-disorder type phase transitions: 1) right-angled twins show curved junctions; 2) needle-shaped twins contain flat wall segments near the needle tip if the elastic behaviour of the mineral is dominated by its anisotroyp; 3) additional bending forces and pinning effects lead to curved walls near the junction that make the needle tip appear more blunt. Bent right-angled twins were analyzed in Gd2(MoO4)3. Linear needle tips were found in WO3, [N(CH3)4]2.ZnBr4 CrAl, BiVO4, GdBa2Cu3O7, and PbZrO. Parabolic tips occur in K2Ba(NO2)4, and GeTe whereas exponential curvatures appear in BaTiO3, KSCN, Pb3(PO4)2, CaTiO3, alkali feldspars, YBa2Cu3O7, and MnAl. The size and shape of the twin microstructure relates to its formation during the phase transition and the subsequent annealing history. The mobility of the twin walls after formation depends not only on the thermal activation but also on the structure of the wall, which may be pinned to impurities on a favorable structural site. Depinnign energies are often large compared with thermal energies for diffusion. This leads to kinetic time scales for twin coarsening that are comparable to geological time scales. Therefore, transformation twins that exhibit needle domains not only indicate that the mineral underwent a structural phase transition but also contain information about its subsequent geological history.

Sibling rivalry: Related bacterial small RNAs and their redundant and non-redundant roles

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Clayton eCaswell

2014-10-01

Full Text Available Small RNA molecules (sRNAs are now recognized as key regulators controlling bacterial gene expression, as sRNAs provide a quick and efficient means of positively or negatively altering the expression of specific genes. To date, numerous sRNAs have been identified and characterized in a myriad of bacterial species, but more recently, a theme in bacterial sRNAs has emerged: the presence of more than one highly related sRNAs produced by a given bacterium, here termed sibling sRNAs. Sibling sRNAs are those that are highly similar at the nucleotide level, and while it might be expected that sibling sRNAs exert identical regulatory functions on the expression of target genes based on their high degree of relatedness, emerging evidence is demonstrating that this is not always the case. Indeed, there are several examples of bacterial sibling sRNAs with non-redundant regulatory functions, but there are also instances of apparent regulatory redundancy between sibling sRNAs. This review provides a comprehensive overview of the current knowledge of bacterial sibling sRNAs, and also discusses important questions about the significance and evolutionary implications of this emerging class of regulators.

Spontaneous unilateral Twin Ectopic Pregnancy: A case report

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هادی اریا منش

2017-03-01

Full Text Available Abstract Aim & Objective: Twin pregnancy in the tube is a few and due to more frequent use of ovulatory medicine and increased maternal mortality rate. In this article, we report a case of  untitled twin ectopic pregnancy. Case study: The pregnant women was a 28 year-old  to had  a  history infertility, PCOD, Abortion and cortege,   too have one 5 years girl by CS and  Mild cramp pain in both abdominal lower quadrants and metroreghia . That have not treatment by projection. The ultra-sonography showed a twin pregnancy uterus with a moderate amount of fluid in pelvic cavity was seen. And do salpanjectimy surgery. Conclusion:  We report one Untitled Spontaneous Twin Ectopic Pregnancy,  is necessary any pregnant woman with  positive BhCG and metrorhoghia must be considered for Ectopic pregnancy. To decrease maternal mortality rate. Key words:

Why Siblings Are Important Agents of Cognitive Development: A Comparison of Siblings and Peers.

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Azmitia, Margarita; Hesser, Joanne

1993-01-01

Found that, in unstructured building sessions, kindergartners were more likely to observe, imitate, and consult their second- or third-grade siblings than their older peers. Older siblings were also more likely to provide additional explanations and positive feedback than older peers when instructing younger children. (MDM)

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

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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…

Parental Divorce and Sibling Relationships: A Research Note

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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…

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

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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.

Detecting genes contributing to longevity using twin data

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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.

Infant-mother and infant-sibling attachment in Zambia.

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Mooya, Haatembo; Sichimba, Francis; Bakermans-Kranenburg, Marian

2016-12-01

This study, the first in Zambia using the Strange Situation Procedure (SSP) to observe attachment relationships and the "very first" observational study of infant-sibling attachment, examined patterns of infant-mother and infant-sibling attachment, and tested their association. We included siblings who were substantially involved in caregiving activities with their younger siblings. We hypothesized that infants would develop attachment relationships to both mothers and siblings; the majority of infants would be classified as securely attached to both caregivers, and infant-mother and infant-sibling attachment would be unrelated. The sample included 88 low-income families in Lusaka, Zambia (average of 3.5 children; SD = 1.5). The SSP distributions (infant-mother) were 59% secure, 24% avoidant and 17% resistant, and 46% secure, 20% avoidant, 5% resistant and 29% disorganized for three- and four-way classifications, respectively. The infant-sibling classifications were 42% secure, 23% avoidant and 35% resistant, and 35% secure, 23% avoidant, 9% resistant and 33% disorganized for three- and four-way classifications, respectively. Infant-mother and infant-sibling attachment relationships were not associated.

Bullying among Siblings: The Role of Personality and Relational Variables

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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…

Sibling Relationships in Early Childhood.

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Dunn, Judy

1983-01-01

Reviews and considers the developmental implications of recent evidence on the nature of sibling interaction from observational studies of preschool children. Argues that, in contrast to complementary interaction, sibling influence is most plausibly associated with reciprocal interaction and with sociocognitive development. (Author/RH)

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

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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 

An Adapted Measure of Sibling Attachment: Factor Structure and Internal Consistency of the Sibling Attachment Inventory in Youth.

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Noel, Valerie A; Francis, Sarah E; Tilley, Micah A

2018-04-01

Parent-youth and peer relationship inventories based on attachment theory measure communication, trust, and alienation, yet sibling relationships have been overlooked. We developed the Sibling Attachment Inventory and evaluated its psychometric properties in a sample of 172 youth ages 10-14 years. We adapted the 25-item Sibling Attachment Inventory from the Inventory of Parent and Peer Attachment-Revised peer measure. Items loaded onto three factors, identified as communication, trust, and alienation, α = 0.93, 0.90, and 0.76, respectively. Sibling trust and alienation correlated with depression (r s  = -0.33, r s  = 0.48) and self-worth (r s  = 0.23; r s  = -0.32); sibling trust and alienation correlated with depression after controlling for parent trust and parent alienation (r s  = -0.23, r s  = 0.22). Preliminary analyses showed good internal consistency, construct validity, and incremental predictive validity. Following replication of these properties, this measure can facilitate large cohort assessments of sibling attachment.

Impact of childhood chronic illnesses on siblings: a literature review.

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O' Brien, Irene; Duffy, Anita; Nicholl, Honor

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. 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. 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', 'chronic illness', 'disability', 'cancer', 'sibling relations', 'sibling adjustment', 'coping', 'family-centred care', 'sibling interventions', 'camps', 'autism', 'Down's syndrome'. Seventeen research studies in total were reviewed. This review focuses on three sibling groups related to children suffering from autism, cancer and Down's syndrome, and are discussed under the following headings: sibling adjustment; family functioning and sibling's coping resources; and intervention programmes. The literature revealed that siblings of children with Down's syndrome were well adjusted to living with their brother or sister. However, there was conflicting information on the adjustment of siblings of children with cancer and autism. An awareness of the harmful effect that living with childhood illness and disability can have on some siblings is essential to enable healthcare professionals to provide supportive interventions to protect siblings' physical and emotional wellbeing.

Siblings and the Development of Prosocial Behavior.

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Dunn, Judy; Munn, Penny

1986-01-01

Examines the capability and motivation of 18- and 24-month-old infants to share, help, comfort, and cooperate with their older siblings; the frequency of such prosocial behavior by both siblings; and the children's response to sibling distress. The relationship between prosocial and conflict behavior was also studied. (HOD)

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

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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…

Ventricular strain changes in monochorionic twins with and without twin-to-twin transfusion syndrome.

Science.gov (United States)

Taylor-Clarke, Marisa C; Matsui, Hikoro; Roughton, Michael; Wimalasundera, Ruwan C; Gardiner, Helena M

2013-06-01

The objective of the study was to investigate whether vector velocity imaging (VVI), a non-Doppler speckle tracking ultrasound technology, is feasible in twin pregnancies and can aid management of twin-twin transfusion syndrome (TTTS). Twenty-seven women pregnant with monochorionic diamniotic twins affected by TTTS and 28 monochorionic pregnancies that did not develop TTTS were included in a prospective case-control study at a fetal medicine center. Fetal echocardiograms were recorded with dummy electrocardiography to retain original frame rates when exported for offline speckle tracking analysis using Syngo-VVI software (Siemens Corp, Munich, Germany). Right and left ventricular (LV) free wall Lagrangian strain was measured from the original coordinates. Within-twin pair ventricular strain differences including relationship to Quintero staging and response to laser therapy for TTTS were analyzed by Wilcoxon signed-rank test. The VVI strain measurements could be analyzed in 182 of 200 TTTS and 96 of 112 non-TTTS control ventricles. Within-pair strain was concordant in non-TTTS controls. Recipient LV strain was reduced at all Quintero stages compared with donors (P < .01). Recipient right ventricular strain was reduced only in stages 3 and 4 (P < .01). Strain improved at a median of 2 weeks following successful laser therapy. Intertwin differences in strain were independent of weight discordance. Recipient LV strain is reduced in stages 1 and 2 TTTS. Within-pair strain discordance may distinguish early TTTS from growth discordance and guide timing of and management following treatment. Copyright © 2013 Mosby, Inc. All rights reserved.

Anaestetic management of caesarean section for conjoint-twins: A case report

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Deogaonkar Shrikrishna G, Aditya Prakash

2014-04-01

Full Text Available At Pravara Rural Hospital a 29 year old patient was admitted for delivery. Patient had conjoint-twins diagnosed after sonography and was posted for elective caesarean section. Patient was managed under general anaesthesia after thorough preparation and under multi-disciplinary involvement. Both the twins females were living and were further managed by neonatologists. Though conjoint-twins are rare and patients coming for delivery with conjoint-twins are still rarer because of early diagnosis and termination, anaesthesiologists working in developing countries and working in remote areas may face such patients. There are very few publications for management of delivery in such patients, hence this case report.

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....

Sibship size, sibling cognitive sensitivity, and children's receptive vocabulary.

Science.gov (United States)

Prime, Heather; Pauker, Sharon; Plamondon, André; Perlman, Michal; Jenkins, Jennifer

2014-02-01

The aim of the current study was to examine the relationship between sibship size and children's vocabulary as a function of quality of sibling interactions. It was hypothesized that coming from a larger sibship (ie, 3+ children) would be related to lower receptive vocabulary in children. However, we expected this association to be moderated by the level of cognitive sensitivity shown by children's next-in-age older siblings. Data on 385 children (mean age = 3.15 years) and their next-in-age older siblings (mean age = 5.57 years) were collected and included demographic questionnaires, direct testing of children's receptive vocabulary, and videos of mother-child and sibling interactions. Sibling dyads were taped engaging in a cooperative building task and tapes were coded for the amount of cognitive sensitivity the older sibling exhibited toward the younger sibling. Hierarchical regression analyses were conducted and showed an interaction between sibship size and sibling cognitive sensitivity in the prediction of children's receptive vocabulary; children exposed to large sibships whose next-in-age older sibling exhibited higher levels of cognitive sensitivity were less likely to show low vocabulary skills when compared with those children exposed to large sibships whose siblings showed lower levels of cognitive sensitivity. Children who show sensitivity to the cognitive needs of their younger siblings provide a rich environment for language development. The negative impact of large sibships on language development is moderated by the presence of an older sibling who shows high cognitive sensitivity.

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

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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…

Siblings and Mental Illness: Heredity vs. Environment.

Science.gov (United States)

Rowe, David C.; Elam, Patricia

1987-01-01

Siblings are far more likely to be different than alike in personality and psychopathology. Different genes and different environmental experiences can account for why one sibling becomes mentally ill and another is not affected. Environmental experiences play a much greater role in sibling differentiation than has been previously recognized.…

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

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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

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.

Modeling the effect of neighboring grains on twin growth in HCP polycrystals

Science.gov (United States)

Kumar, M. Arul; Beyerlein, I. J.; Lebensohn, R. A.; Tomé, C. N.

2017-09-01

In this paper, we study the dependence of neighboring grain orientation on the local stress state around a deformation twin in a hexagonal close packed (HCP) crystal and its effects on the resistance against twin thickening. We use a recently developed, full-field elasto-visco-plastic formulation based on fast Fourier transforms that account for the twinning shear transformation imposed by the twin lamella. The study is applied to Mg, Zr and Ti, since these HCP metals tend to deform by activation of different types of slip modes. The analysis shows that the local stress along the twin boundary are strongly controlled by the relative orientation of the easiest deformation modes in the neighboring grain with respect to the twin lamella in the parent grain. A geometric expression that captures this parent-neighbor relationship is proposed and incorporated into a larger scale, mean-field visco-plastic self-consistent model to simulate the role of neighboring grain orientation on twin thickening. We demonstrate that the approach improves the prediction of twin area fraction distribution when compared with experimental observations.

Inherited multicentric osteolysis: case report of three siblings treated with bisphosphonate

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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.

INTEGRATED TWIN TOWERS DAN ISLAMISASI ILMU

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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.

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…

Life Events, Sibling Warmth, and Youths' Adjustment

Science.gov (United States)

Waite, Evelyn B.; Shanahan, Lilly; Calkins, Susan D.; Keane, Susan P.; O'Brien, Marion

2011-01-01

Sibling warmth has been identified as a protective factor from life events, but stressor-support match-mismatch and social domains perspectives suggest that sibling warmth may not efficiently protect youths from all types of life events. We tested whether sibling warmth moderated the association between each of family-wide, youths' personal, and…

Sibling relationships in individuals with Angelman syndrome: A comparative study

NARCIS (Netherlands)

Love, V.; Richters, L.P.H.; Didden, H.C.M.; Korzilius, H.P.L.M.; Machalicek, W.A.

2012-01-01

Objective: Investigating the impact of Angelman syndrome on the sibling relationship. Methods: This study explored differences in sibling relationships between children with a typically-developing sibling (n = 55) and children with a sibling with Angelman syndrome (n 44). Sibling relationships were

Marital status and twins' health and behavior: an analysis of middle-aged Danish twins

DEFF Research Database (Denmark)

Osler, Merete; McGue, Matt; Lund, Rikke

2008-01-01

mass index (BMI), depression symptoms, self-rated health, cognitive function, physical activity, smoking, and alcohol intake. RESULTS: Among all 2350 individual twins, men who were divorced/widowed or never married had higher depression scores, lower cognitive test scores, lower physical activity....../widowed twin had higher average depression scores and was more likely to be a smoker. Never married twins had lower physical activity scores and never married male twins had higher BMI and higher depression scores than their married co-twin. CONCLUSION: This study suggests that the relationships of adult...... divorce with depression and smoking in Danish twins are due to the stressful effects of marital dissolution, but that marital differences in other health and behavioral outcomes are most consistent with selection effects related to genetic or rearing environmental factors....

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...... 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...... presents results from full-scale measurements on the special arrangement of twin cables adopted for the Øresund Bridge. The monitoring system records wind and weather conditions, as well as accelerations of certain cables and a few locations on the deck and tower. Using the Eigenvalue Realization Algorithm...

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

• Sibling relationships in individuals with Angelman syndrome: a comparative study.

  Science.gov (United States)

  Love, Victoria; Richters, Lotte; Didden, Robert; Korzilius, Hubert; Machalicek, Wendy

  2012-01-01

  Investigating the impact of Angelman syndrome on the sibling relationship. This study explored differences in sibling relationships between children with a typically-developing sibling (n = 55) and children with a sibling with Angelman syndrome (n = 44). Sibling relationships were compared on four factors and 16 sub-scales of the Sibling Relationship Questionnaire-Revised. Results showed significant differences in mean scores on each of the four factors (i.e. Warmth/Closeness, Conflict, Rivalry and Dominance/Nurturance) and most of the sub-scales. ANCOVAs showed that demographic variables (number of siblings, living in a two-parent vs single parent household, gender, participant's age, place of residence) did not influence significant differences in sibling relationships between the two groups. Having a brother or sister with Angelman syndrome may influence the way in which the sibling perceives the sibling relationship. This may have important implications for family-centred intervention for this population.

• Vaccination delays maedi-visna lentivirus infection in a naturally-infected sheep flock

  Directory of Open Access Journals (Sweden)

  Gudnadóttir Margrét

  2013-01-01

  Full Text Available Abstract Background The Maedi-Visna (MV lentivirus causes two slowly progressive eventually fatal diseases of sheep, Maedi, a progressive interstitial pneumonia, and Visna, a progressive demyelinating disease of the central nervous system. Other lentiviruses also cause fatal slow infections in their natural hosts, e.g. the HIV virus in humans. Results of experimental vaccination against any lentivirus where vaccinees are challenged by natural routes, may therefore be of general interest. From 1991–1998 experiments with formalin-inactivated whole Maedi-Visna virus vaccine were carried out in the Department of Microbiology at the University of Iceland. Western Blot tests showed good immune response to all major proteins of the virus. When aluminium hydroxide was added to the vaccine all vaccinees developed neutralizing antibodies to the vaccine strain at titers 1/8 – 1/256. After housing 5 twin pairs, one twin in each pair vaccinated, the other unvaccinated, with infected sheep for 4 years, all the unvaccinated twins became infected, but only 2 of their vaccinated siblings as confirmed by virus cultivation experiments on tissues from their lungs spleens lymph nodes and choroid plexuses. Results One twin in each of 40 female twin pairs, born into a Maedi-Visna-infected sheep flock and kept under natural farming conditions in Cyprus, was vaccinated at birth, 3 weeks and 3 months, with formalin-inactivated whole Maedi-Visna lentivirus vaccine adjuvanted with aluminium hydroxide. 17 mothers of the twins were seronegative, 13 seroconverting and 10 had old infection. Of 17 vaccinees born to seronegative mothers 9 were uninfected at 28 months, but only 2 of their unvaccinated siblings. Of 13 unvaccinated twins born to seroconverting mothers, 12 caught infection during their first 10 weeks, but only 4 of their vaccinated siblings. Vaccination had no effects on 10 vaccinees born to mothers with long-standing Maedi-Visna infections and broad andibody

• Sibling Relationships and Empathy Across the Transition to Adolescence Sibling Relationships and Empathy Across the Transition to Adolescence

  Science.gov (United States)

  Lam, Chun Bun; Solmeyer, Anna R.; McHale, Susan M.

  2012-01-01

  Although socioemotional competencies have been identified as key components of youths’ positive development, most studies on empathy are cross-sectional, and research on the role of the family has focused almost exclusively on parental socialization. This study examined the developmental course of empathy from age 7 to 14 and the within-person associations between sibling warmth and conflict and youths’ empathy. On three occasions across 2 years, mothers, fathers, and the two eldest siblings from 201 White, working- and middle-class families provided questionnaire data. Multilevel models revealed that, controlling for youths’ pubertal status and parental education, girls’ empathy increased during the transition to adolescence and then leveled off, but boys’ lower levels of empathy remained relatively unchanged. Moreover, controlling for parental responsiveness and marital love, at times when firstborns and second-borns reported more sibling warmth and less sibling conflict than usual, they also reported more empathy than usual. The within-person association between sibling warmth and empathy also became stronger over time. Findings highlight gender differences in empathy development and the unique role of siblings in shaping each other’s socioemotional characteristics during adolescence. PMID:22714744

• Genetic modifiers of nutritional status in cystic fibrosis1234

  Science.gov (United States)

  Bradley, Gia M; Blackman, Scott M; Watson, Christopher P; Doshi, Vishal K; Cutting, Garry R

  2012-01-01

  Background: Improved nutrition early in life is associated with better pulmonary function for patients with cystic fibrosis (CF). However, nutritional status is poorly correlated with the CFTR genotype. Objective: We investigated the extent to which modifier genes influence nutrition in children with CF. Design: BMI data were longitudinally collected from the CF Twin-Sibling Study and Cystic Fibrosis Foundation Patient Registry for twins and siblings from 2000 to 2010. A nutritional phenotype was derived for 1124 subjects by calculating the average BMI z score from 5–10 y of age (BMI-z5to10). The genetic contribution to the variation in BMI-z5to10 (ie, heritability) was estimated by comparing the similarity of the phenotype in monozygous twins to that in dizygous twins and siblings. Linkage analysis identified potential modifier-gene loci. Results: The median BMI-z5to10 was −0.07 (range: −3.89 to 2.30), which corresponded to the 47th CDC percentile. BMI-z5to10 was negatively correlated with pancreatic insufficiency, history of meconium ileus, and female sex but positively correlated with later birth cohorts and lung function. Monozygous twins showed greater concordance for BMI-z5to10 than did dizygous twins and siblings; heritability estimates from same-sex twin-only analyses ranged from 0.54 to 0.82. For 1010 subjects with pancreatic insufficiency, genome-wide significant linkage was identified on chromosomes 1p36.1 [log of odds (LOD): 5.3] and 5q14 (LOD: 5.1). These loci explained ≥16% and ≥15%, respectively, of the BMI variance. Conclusions: The analysis of twins and siblings with CF indicates a prominent role for genes other than CFTR to BMI variation. Specifically, regions on chromosomes 1 and 5 appear to harbor genetic modifiers of substantial effect. PMID:23134884

• Genetic modifiers of nutritional status in cystic fibrosis.

  Science.gov (United States)

  Bradley, Gia M; Blackman, Scott M; Watson, Christopher P; Doshi, Vishal K; Cutting, Garry R

  2012-12-01

  Improved nutrition early in life is associated with better pulmonary function for patients with cystic fibrosis (CF). However, nutritional status is poorly correlated with the CFTR genotype. We investigated the extent to which modifier genes influence nutrition in children with CF. BMI data were longitudinally collected from the CF Twin-Sibling Study and Cystic Fibrosis Foundation Patient Registry for twins and siblings from 2000 to 2010. A nutritional phenotype was derived for 1124 subjects by calculating the average BMI z score from 5-10 y of age (BMI-z(5to10)). The genetic contribution to the variation in BMI-z(5to10) (ie, heritability) was estimated by comparing the similarity of the phenotype in monozygous twins to that in dizygous twins and siblings. Linkage analysis identified potential modifier-gene loci. The median BMI-z(5to10) was -0.07 (range: -3.89 to 2.30), which corresponded to the 47th CDC percentile. BMI-z(5to10) was negatively correlated with pancreatic insufficiency, history of meconium ileus, and female sex but positively correlated with later birth cohorts and lung function. Monozygous twins showed greater concordance for BMI-z(5to10) than did dizygous twins and siblings; heritability estimates from same-sex twin-only analyses ranged from 0.54 to 0.82. For 1010 subjects with pancreatic insufficiency, genome-wide significant linkage was identified on chromosomes 1p36.1 [log of odds (LOD): 5.3] and 5q14 (LOD: 5.1). These loci explained ≥16% and ≥15%, respectively, of the BMI variance. The analysis of twins and siblings with CF indicates a prominent role for genes other than CFTR to BMI variation. Specifically, regions on chromosomes 1 and 5 appear to harbor genetic modifiers of substantial effect.

• Family structure and risk factors for schizophrenia: case-sibling study

  Directory of Open Access Journals (Sweden)

  Lönnqvist Jouko

  2004-11-01

  Full Text Available Abstract Background Several family structure-related factors, such as birth order, family size, parental age, and age differences to siblings, have been suggested as risk factors for schizophrenia. We examined how family-structure-related variables modified the risk of schizophrenia in Finnish families with at least one child with schizophrenia born from 1950 to 1976. Methods We used case-sibling design, a variant of the matched case-control design in the analysis. Patients hospitalized for schizophrenia between 1969 and 1996 were identified from the Finnish Hospital Discharge Register, and their families from the Population Register Center. Only families with at least two children (7914 sibships and 21059 individuals were included in the analysis. Conditional logistic regression with sex, birth cohort, maternal schizophrenia status, and several family-related variables as explanatory variables was used in the case-sibling design. The effect of variables with the same value in each sibship was analyzed using ordinary logistic regression. Results Having a sibling who was less than five years older (OR 1.46, 95% CI 1.29–1.66, or being the firstborn (first born vs. second born 1.62, 1.87–1.4 predicted an elevated risk, but having siblings who were more than ten years older predicted a lower risk (0.66, 0.56–0.79. Conclusions Several family-structure-related variables were identified as risk factors for schizophrenia. The underlying causative mechanisms are likely to be variable.

• 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…

• Register-based research on twins

  DEFF Research Database (Denmark)

  Christensen, Kaare; Ohm Kyvik, Kirsten; Holm, Niels V

  2011-01-01

  Introduction: The Danish Twin Registry (DTR) has for more than 50 years been based on surveys and clinical investigations and over the two last decades also on register linkage. Currently these two approaches are merged within Statistics Denmark. Research topics: Here we report on three major...... groups of register-based research in the DTR that used the uniqueness of twinning. First, we focus on the ''long-term prognosis'' of being a twin compared with being a singleton and show that Danish twins have health trajectories in adulthood similar to singletons, which is a result of interest for twins...... illustrate how the co-twin control method in a register setting can be used to control for the effect of rearing environment and genetic factors in studies of the association between exposures and health. CONCLUSION: The spectrum of register-based twin studies is very wide and have changed in accordance...

• The role of older siblings in infant motor development.

  Science.gov (United States)

  Leonard, Hayley C; Hill, Elisabeth L

  2016-12-01

  Previous research has suggested that infant motor skills may be affected by older siblings but has not considered whether this is due to specific characteristics of the older sibling or of the quality of the sibling relationship. The current study used a longitudinal diary method to record infant motor milestones from 23 infants with older siblings along with parent reports and standardized assessments of motor skills. Parent reports of the older siblings' motor skills and the sibling relationship were also collected until the infants were 18months old. The motor skills, age, and sex of the older siblings were not significantly related to any measure of infant motor development. A significant correlation was revealed between perceived agonism between siblings and infant fine motor skills at 18months, suggesting the importance of considering reciprocal effects of motor development on sibling relationships. Overall, the suggestion that older siblings may provide a good model of motor skills for infants is not supported by the current data. In the future, it will be important to assess the dynamic interactions between different factors in predicting infant motor development, allowing early identification of motor difficulties, which could affect other areas of cognitive development and health. Copyright © 2016 Elsevier Inc. All rights reserved.

• BayesTwin: An R Package for Bayesian Inference of Item-Level Twin Data

  Directory of Open Access Journals (Sweden)

  Inga Schwabe

  2017-11-01

  Full Text Available BayesTwin is an open-source R package that serves as a pipeline to the MCMC program JAGS to perform Bayesian inference on genetically-informative hierarchical twin data. Simultaneously to the biometric model, an item response theory (IRT measurement model is estimated, allowing analysis of the raw phenotypic (item-level data. The integration of such a measurement model is important since earlier research has shown that an analysis based on an aggregated measure (e.g., a sum-score based analysis can lead to an underestimation of heritability and the spurious finding of genotype-environment interactions. The package includes all common biometric and IRT models as well as functions that help plot relevant information or determine whether the analysis was performed well. Funding statement: Partly funded by the PROO grant 411-12-623 from the Netherlands Organisation for Scientific Research (NWO.

• Sibling curves of quadratic polynomials | Wiggins | Quaestiones ...

  African Journals Online (AJOL)

  Sibling curves were demonstrated in [1, 2] as a novel way to visualize the zeroes of real valued functions. In [3] it was shown that a polynomial of degree n has n sibling curves. This paper focuses on the algebraic and geometric properites of the sibling curves of real and complex quadratic polynomials. Key words: Quadratic ...

• 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.

• Examining the Role of Communication on Sibling Relationship Quality and Interaction for Sibling Pairs with and without a Developmental Disability

  Science.gov (United States)

  Smith, Ashlyn L.; Romski, MaryAnn; Sevcik, Rose A.

  2013-01-01

  This study examined communication interaction patterns when one sibling had a developmental disability as well as the role of communication skills in sibling relationship quality. Thirty sibling dyads were categorized into one of three communication status groups: emerging, context-dependent, and independent communicators. Independent…

• Birth size and gestational age in opposite-sex twins as compared to same-sex twins

  DEFF Research Database (Denmark)

  Jelenkovic, Aline; Sund, Reijo; Yokoyama, Yoshie

  2018-01-01

  It is well established that boys are born heavier and longer than girls, but it remains unclear whether birth size in twins is affected by the sex of their co-twin. We conducted an individual-based pooled analysis of 21 twin cohorts in 15 countries derived from the COllaborative project of Develo......It is well established that boys are born heavier and longer than girls, but it remains unclear whether birth size in twins is affected by the sex of their co-twin. We conducted an individual-based pooled analysis of 21 twin cohorts in 15 countries derived from the COllaborative project....... In girls, birth size was not associated (5 g birth weight; 95% CI -8 to -18 and -0.089 cm birth length; 95% CI -0.202 to 0.025) with the sex of the co-twin. Gestational age was slightly shorter in boy-boy pairs than in boy-girl and girl-girl pairs. When birth size was standardized by gestational age......, the magnitude of the associations was attenuated in boys, particularly for birth weight. In conclusion, boys with a co-twin sister are heavier and longer at birth than those with a co-twin brother. However, these differences are modest and partly explained by a longer gestation in the presence of a co...

• Familial concordance of phenotype and microbial variation among siblings with CF.

  Science.gov (United States)

  Picard, Elie; Aviram, Micha; Yahav, Yaakov; Rivlin, Joseph; Blau, Hanna; Bentur, Lea; Avital, Avraham; Villa, Yael; Schwartz, Shepard; Kerem, Batsheva; Kerem, Eitan

  2004-10-01

  The clinical spectrum of cystic fibrosis (CF) is influenced by the cystic fibrosis transmembrane conductance regulator (CFTR) genotype. However, variable courses of the disease were demonstrated among patients with identical genotypes. Since siblings share identical CFTR mutations and environmental factors, they can serve as a model to assess the effect of modifier genes on disease expression, and also to evaluate cross-infection. The aim of this study was to compare disease expression among siblings with CF. All sibling pairs treated at 7 CF centers in Israel were included in the study. Data were collected from patients' medical charts. Fifty families with at least 2 siblings were identified. As expected, the second-born sibling was diagnosed at an earlier age compared to the first-born. The mode of CF presentation at diagnosis showed significant familial concordance. In the families where the first sibling presented with gastrointestinal manifestations, 79% of the second siblings also presented with gastrointestinal manifestations. When gastrointestinal manifestations were absent in the first sibling, only 12% of the second siblings presented with gastrointestinal manifestations (P sibling presented with respiratory symptoms, 60% of the second siblings presented with the similar symptoms. However, when the first sibling presented without respiratory symptoms, only 12% of the second siblings presented with respiratory symptoms (P sibling had MI, 8 (80%) of the subsequent siblings had MI. On the other hand, in the 39 families where the first-born sibling did not have MI, only 2 (5%) subsequent siblings had MI (P siblings. P. aeruginosa grew from sputum in 89% of our study patients. When P. aeruginosa was isolated from the first-born patient, 91% of the second siblings were also positive for P. aeruginosa, whereas when the initial sibling was not a carrier of P. aeruginosa, only 50% of subsequent siblings were positive (P sibling than in the first for the two

• Between Two Worlds: Twin Peaks and the Film/Television Divide

  Directory of Open Access Journals (Sweden)

  Siobhan Lyons

  2017-04-01

  Full Text Available In 1992, the year David Lynch’s cult television series 'Twin Peaks' was pulled off air, Lynch released the film 'Twin Peaks: Fire Walk with Me', a prequel to the television series which filled in some of the gaps left from the series finale cliff-hanger. The film was received with unanimously negative reviews from critics and fans alike, condemning both its subtle and obvious deviations from the series and its inclusion of the character Laura Palmer, whose absence was a crucial narrative device at the centre of 'Twin Peaks'. In film form, the 'Twin Peaks' narrative suffers from thematic inconsistencies and aesthetic deviations. The scope of 'Twin Peaks' seems much more capable in the setting of television and its gradual, episodic set-up. In recent years, however, with the announcement of a revival of the series, retrospective analysis of 'Fire Walk with Me' has become more positive, and the film has also become an integral part of the overall 'Twin Peaks' canon. Nevertheless, the transition from television to film in the case of 'Twin Peaks' has remained a point of fan and scholarly controversy, with issues of continuity, narrative and aesthetics between the two different mediums continually being addressed and compared. In light of the news that the new season of 'Twin Peaks' is set to be released in 2017, this article examines the significance of 'Fire Walk with Me' as a cinematic counterpart and prequel to the original series, and how this has helped shape – whether positively or not – the overall narrative of 'Twin Peaks'.

The role of older siblings in infant motor development

OpenAIRE

Leonard, Hayley; Hill, EL

2016-01-01

Previous research has suggested that infant motor skills may be affected by older siblings, but has not considered whether this is due to specific characteristics of the older sibling, or of the quality of the sibling relationship. The current study used a longitudinal diary method to record infant motor milestones from 23 infants with older siblings, along with parent reports and standardised assessments of motor skills. Parent reports of the older siblings’ motor skills and the sibling rela...

Genetic and environmental influences on temperament in the first year of life: the Puerto Rico Infant Twin Study (PRINTS).

Science.gov (United States)

Silberg, Judy L; Miguel, Vivian Febo San; Murrelle, E Lenn; Prom, Elizabeth; Bates, John E; Canino, Glorisa; Egger, Helen; Eaves, Lindon J

2005-08-01

Three dimensions of temperament -- difficult temperament, unadaptablility and unsociability -- were assessed in the first year of life by maternal interview in twins born in Puerto Rico during 2001 and 2002. Eight hundred and sixty-five eligible mothers (80%) were traced and interviewed. Model-fitting results showed that additive genetic factors and the individual specific environment contributed to variation in all three dimensions. In addition, the pattern of variances and correlations suggested that sibling contrast effects influence ratings of difficult temperament. Moderate effects of the shared environment contributed to ratings of adaptability and sociability. There was a significant genetic correlation between difficult temperament and unadaptability. Genetic and environmental effects do not differ significantly between boys and girls. The study is the first population-based study of Puerto Rican twins and one of few to attempt the assessment of behavior in the first year. Preliminary results for difficult temperament and sociability were consistent with those in other populations and ages. In contrast, a significant effect of the shared environment on the temperamental trait of unadaptability has not been reported previously.

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,…

Familial risk and sibling mentalization: Links with preschoolers' internalizing problems.

Science.gov (United States)

Rodrigues, Michelle; Binnoon-Erez, Noam; Prime, Heather; Perlman, Michal; Jenkins, Jennifer M

2017-09-01

The current study explored whether older sibling mentalization moderated the relationship between familial risk for internalizing symptoms and the development of future internalizing problems in the younger siblings, referred to as target children. Data were collected on 397 older siblings at Time 1 (T1) when target children were newborn and their older siblings were on average 2.61 years old (SD = .75). Target children were on average 1.60 years old at Time 2 (T2). Internalizing problems were assessed via mother and partner reports. Familial risk was operationalized as the average of all older siblings' level of internalizing problems. Older sibling mentalization, indexed by internal state talk and reasoning, was observed and coded during a sibling pretend-play interaction at T2. Results revealed a significant interaction between familial risk of internalizing problems and older siblings' mentalizing abilities, showing that familial risk was related to target children's internalizing problems in the absence of sibling mentalization. Familial risk was not associated with target children's internalizing problems when siblings demonstrated mentalizing abilities. Findings support the need to consider sibling mentalization as a protective factor for children's internalizing problems. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Fetal growth disorders in twin gestations.

LENUS (Irish Health Repository)

Breathnach, Fionnuala M

2012-06-01

Twin growth is frequently mismatched. This review serves to explore the pathophysiologic mechanisms that underlie growth aberrations in twin gestations, the prenatal recognition of abnormal twin growth, and the critical importance of stratifying management of abnormal twin growth by chorionicity. Although poor in utero growth of both twins may reflect maternal factors resulting in global uteroplacental dysfunction, discordant twin growth may be attributed to differences in genetic potential between co-twins, placental dysfunction confined to one placenta only, or one placental territory within a shared placenta. In addition, twin-twin transfusion syndrome represents a distinct entity of which discordant growth is a common feature. Discordant growth is recognized as an independent risk factor for adverse perinatal outcome. Intertwin birth weight disparity of 18% or more should be considered to represent a discordance threshold, which serves as an independent risk factor for adverse perinatal outcome. At this cutoff, perinatal morbidity is found to increase both for the larger and the smaller twin within a discordant pair. There remains uncertainty surrounding the sonographic parameters that are most predictive of discordance. Although heightening of fetal surveillance in the face of discordant twin growth follows the principles applied to singleton gestations complicated by fetal growth restriction, the timing of intervention is largely influenced by chorionicity.

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…

The experiences of Latino siblings of children with developmental disabilities.

Science.gov (United States)

Kao, B; Romero-Bosch, L; Plante, W; Lobato, D

2012-07-01

This qualitative study explored the experiences of Latino siblings of children with developmental disabilities. Parents and typically developing siblings from 15 Latino families with a child with a developmental disability participated in separate interviews. Using consensual qualitative research methodology, domains reflecting siblings' relationships, emotional experiences and communication about the disability were identified. The child's need for caregiving was a prominent topic in the sibling and parent narratives. Parents reported concerns about siblings' experience of differential treatment, whereas siblings reported concerns about restricted social activities because of their brother/sister. Including multiple informants revealed commonalities and differences in parents' and siblings' perspectives on the impact of a child's disability. The importance of considering sibling adaptation in sociocultural context is discussed. © 2011 Blackwell Publishing Ltd.

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

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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.

Long-Term Neuropsychological Outcome in Preterm Twins

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Giovanni Iannone

2006-01-01

Full Text Available Few long-term studies have yet described neuropsychological outcome in preterm twins. Our aim was to assess, by long-term evaluation, neuropsychological outcome in preterm twins in order to define a correct follow-up program. Our study was a cohort one, with an index and a comparison group. Neonatal medical records of all preterm newborns admitted to our centre between 1991 and 1997 were reviewed and selected patients were recalled. The sample population included two matched groups of children aged 6—12 years, 86 twins and 86 singletons, submitted to paediatric, neurological, psychological, and ophthalmological examinations. Inclusion criteria were twin pregnancy and gestational age 27—36 weeks for index group; same gestational age, but single pregnancy, for the comparison group. All children underwent paediatric and neuropsychiatric examinations, cognitive assessment, and psychological evaluation by standardized tests for screening of learning specific disorders and language difficulties, and finally, ophthalmological examination. In order to study their role in predicting neuropsychological outcome, we examined some perinatal prognostic factors by statistical analysis. Unfavourable neuropsychological outcome was observed in 55/172 (32% children, with different prevalence in the two groups, 42/172 (24% in twins and 13/172 (8% in singletons. Statistical analysis performed for examined prognostic factors showed significant differences in neuropsychological outcome with regard only to gestational age < 32 weeks, low birth weight, intraventricular haemorrhage, and periventricular leukomalacia. The incidence of neuropsychological diseases in the two groups showed significant difference about language and learning difficulties. Our data suggest that preterm twins represent a particular high-risk category of premature babies, mostly regarding the risk of so-called “minimal brain dysfunction”, so a careful follow-up is recommended.

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

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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.

Parent & Child Perceptions of Child Health after Sibling Death

OpenAIRE

Roche, Rosa M.; Brooten, Dorothy; Youngblut, JoAnne M.

2016-01-01

Background Understanding children?s health after a sibling?s death and what factors may affect it is important for treatment and clinical care. This study compared children?s and their parents? perceptions of children?s health and identified relationships of children?s age, gender, race/ethnicity, anxiety, and depression and sibling?s cause of death to these perceptions at 2 and 4 months after sibling death. Methods 64 children and 48 parents rated the child?s health ?now? and ?now vs before?...

[Sibling relations between individuation and attachment: attempt at a conceptualization].

Science.gov (United States)

Seiffge-Krenke, I

2001-01-01

Although sibling relationships can be considered as one of the most durable and intensive relationships, not much research in developmental psychology and family research has been done on this issue. The strong focus on parents, more specifically on mothers, stood in the way of adequate conceptualization and understanding of the function and contribution of siblings to individual development and family interaction. In this contribution a conceptualization of sibling relationships is presented. Siblings as objects of aggressive and sexual feelings as well as the function of siblings in the family system, for example, as parentification and negative identity is emphasized. In addition, the different qualities of sibling relationships, for example, envy, rivalry, similarity, and difference, are emphasized. The function of siblings as love objects is stressed, and the role of siblings as support as well as teaching object is illustrated. Finally, it is emphasized that, similar to relationships between parents and child, the quality of sibling relationships changed over time and leads, for example, to a detachment between sibling relationships during adolescence.

Early prenatal diagnosis of ischiopagus conjoined twins

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Ahmet Mete Ergenoğlu

2014-03-01

Full Text Available Introduction: Conjoined twins are very rare and the incidence of them vary about 1/50,000 and 1/100,000. They are named according to the joint parts. Embryos are conjoined at the level of ischium in ischiopagus. A case of ischiopagus will be presented in this article. Case: A twenty-seven year old women who is 9-10 weeks pregnant with a history of 1 abortus applied to the Ege University Department of Obstetrics and Gynecology for routine follow-up. Ultrasonography revealed a twin pregnancy but the embryos were attached at the pelvic region. 3D Doppler sonography confirmed the diagnosis of ischiopagus tetrapus. The patient's decision of termination of pregnancy is concluded at Perinatology Council of the clinic. Conclusion: Ischiopagus conjoined twins are very rare. Early prenatal diagnosis will prevent the maternal complications during the termination of the pregnancy.

Twin-Star: Adding a new dimension for treatment of Class II noncompliant patients

Directory of Open Access Journals (Sweden)

Sonali Malay Mahadevia

2014-01-01

Full Text Available The orthodontist of today faces the herculian task in getting kids to wear myofunctional appliances. Even the Twin-Block, which is claimed to be one of the most patient friendly appliances, is not so easily accepted by the growing child of the 21 st century. An innovative modification of the Twin-Block called Twin-Star is hereby presented. Compared with the traditionally constructed Twin-Block, the Twin-Star proves to be esthetically superior, with a higher level of comfort and is less bulky (as it is palate free and hence easily accepted by the patient. It is a boon to the orthodontist too as it can be made in a single sitting by the orthodontist himself.

Cohort Profile : The National Academy of Sciences-National Research Council Twin Registry (NAS-NRC Twin Registry)

NARCIS (Netherlands)

Gatz, Margaret; Harris, Jennifer R.; Kaprio, Jaakko; McGue, Matt; Smith, Nicholas L.; Snieder, Harold; Spiro, Avron; Butler, David A.

The National Academy of Sciences-National Research Council Twin Registry (NAS-NRC Twin Registry) is a comprehensive registry of White male twin pairs born in the USA between 1917 and 1927, both of the twins having served in the military. The purpose was medical research and ultimately improved

A study about siblings in the face of intellectual disability

Directory of Open Access Journals (Sweden)

Olga Lizasoain

2010-05-01

Full Text Available Research has shown that siblings of a person with intellectual disabilities can present problems of identification and socialization, the need for compensation, early adoption of large responsibilities, feelings of abandonment, guilt, shame or sadness. Nevertheless, if the needs of these brothers and sisters are facing, disability can become a source of personal and family enrichment. This article presents the initial conclusions drawn after a series of personal interviews conducted with siblings of students in a special education school. Awareness of the issue leads us to approach this study with the aim of providing guidelines of intervention to help siblings to minimize the potential negative impact of having a brother or sister with intellectual disabilities, and facilitate the development of attitudes and behaviours that enable them to face stressful situations in a constructive manner. Thanks to the direct experience of those who have been confronted with this situation, is issued to prevent psychosocial problems associated with having a brother or sister with these features.

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.

Living with a brother or sister with epilepsy: siblings' experiences.

Science.gov (United States)

Hames, Annette; Appleton, Richard

2009-12-01

There is conflicting evidence about the impact of disability upon siblings, and very little research on the siblings of children with epilepsy. There is some evidence that siblings who have less accurate information exhibit more distress. The aim of this study was to assess siblings' response to having a brother or sister with epilepsy and to begin to develop information for them. Parents of children attending paediatric neurology outpatient departments were invited to participate in a pilot study. Parents who consented to take part were asked if they had previously received information for siblings. Parents and siblings participated in a semi-structured interview and siblings were also invited to submit a personal account of living with a brother or sister who had epilepsy. Twenty-five families with a child with epilepsy aged 2.5-15 years initially agreed to take part. None of the families stated that they had ever seen or received any information specifically for siblings. Fourteen siblings from the 25 families, aged 8-25 years, provided a personal account of what it was like living with a brother or sister with epilepsy. Siblings' accounts included both negative and positive feelings, and specifically feelings of care and love for their sibling. This initial study suggests that siblings of children with epilepsy have many positive but also early negative feelings. The results are limited by the size of the study, the fact that most siblings were older sisters, and the mean time since diagnosis was 6 years. Finally, it is hoped that the personal accounts collected in this study will be published for the benefit of other siblings of children with epilepsy.

The potential efficacy of cognitive-behavioral therapy in the treatment of siblings of children with special needs

Directory of Open Access Journals (Sweden)

Mojca Petrič

2016-08-01

Full Text Available In this article, we present the empirical findings on psychosocial adjustment of siblings of children with special needs, as well as cognitive-behavioural therapy (CBT and its techniques as a potential treatment choice. We conclude that most siblings adjust rather well to having a brother/sister with special needs. Still, they are dealing with more challenges and difficulties than siblings of children with typical development, such as having a role of a caregiver, or experiencing stigmatizing interactions with their peers or others, some also develop psychological and/or adjustment problems. There have been some sibling support programs, but little research has been conducted to address their efficacy, and the current findings are contradictory. Considering the challenges the siblings are facing, we believe CBT is a reasonable treatment option.

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

Siblings of the Hearing Impaired: Perspectives for Parents.

Science.gov (United States)

Atkins, Dale V.

1987-01-01

The author describes the concerns and needs of siblings of hearing-impaired children, offering practical suggestions for parents, educators, and mental health and community service workers. Examples of successful programs for siblings that provide emotional support, training and information about their siblings' disability, and effective…

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.

Perceptions of sibling relationships during middle childhood and adolescence.

Science.gov (United States)

Buhrmester, D; Furman, W

1990-10-01

Children in grades 3, 6, 9, and 12 were administered the Sibling Relationship Questionnaire. Relationships were rated as progressively more egalitarian across the 4 grade groups, with adolescents reporting less dominance and nurturance by their older siblings than younger participants. Adolescents also reported less companionship, intimacy, and affection with siblings than younger participants reported. Levels of perceived conflict with younger siblings were moderately high across all 4 grades, whereas ratings of conflict with older siblings were progressively lower across the 4 grades. The findings suggested that sibling relationships: (a) become more egalitarian and less asymmetrical with age, (b) become less intense with age, and (c) encompass experiences that are partially determined by the child's standing in the family constellation.

Children with Autism & Their Siblings

Science.gov (United States)

Cancro, Ralph

2008-01-01

The parent of the child with autism is faced with many home management challenges, not the least of which is the achievement of intra-family harmony among siblings. Sibling rivalry occurs in all families. However, the presence of a child with autism may, in some instances, intensify this rivalry. In this article, the author provides tips for…

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)

The utility of twins in developmental cognitive neuroscience research: How twins strengthen the ABCD research design.

Science.gov (United States)

Iacono, William G; Heath, Andrew C; Hewitt, John K; Neale, Michael C; Banich, Marie T; Luciana, Monica M; Madden, Pamela A; Barch, Deanna M; Bjork, James M

2018-08-01

The ABCD twin study will elucidate the genetic and environmental contributions to a wide range of mental and physical health outcomes in children, including substance use, brain and behavioral development, and their interrelationship. Comparisons within and between monozygotic and dizygotic twin pairs, further powered by multiple assessments, provide information about genetic and environmental contributions to developmental associations, and enable stronger tests of causal hypotheses, than do comparisons involving unrelated children. Thus a sub-study of 800 pairs of same-sex twins was embedded within the overall Adolescent Brain and Cognitive Development (ABCD) design. The ABCD Twin Hub comprises four leading centers for twin research in Minnesota, Colorado, Virginia, and Missouri. Each site is enrolling 200 twin pairs, as well as singletons. The twins are recruited from registries of all twin births in each State during 2006-2008. Singletons at each site are recruited following the same school-based procedures as the rest of the ABCD study. This paper describes the background and rationale for the ABCD twin study, the ascertainment of twin pairs and implementation strategy at each site, and the details of the proposed analytic strategies to quantify genetic and environmental influences and test hypotheses critical to the aims of the ABCD study. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Infantile malignant osteopetrosis: A case report of three siblings

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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.

Perinatal Outcomes of Monochorionic-Diamniotic Twin Pregnancies Uncomplicated at 28 Weeks of Gestation

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Shunji Suzuki

2016-01-01

Full Text Available We examined the prevalence of specific perinatal complications of monochorionic-diamniotic twin pregnancies in cases without any abnormal findings until the second trimester of pregnancy. This was a retrospective cohort study performed at a tertiary perinatal center in Tokyo, Japan. There were 88 cases of uncomplicated monochorionic-diamniotic twin pregnancies at 28 weeks of gestation. In five of them (5.7%, there were serious complications associated with placental circulatory imbalance between the twins during the third trimester of pregnancy. Two cases were complicated by twin–twin transfusion syndrome, two cases were complicated by twin anemia–polycythemia sequence, and one case was complicated by acute twin–twin transfusion syndrome. In the five cases, no abnormal ultrasonographic findings or symptoms were recognized one or two weeks prior to the diagnosis. Fifty-eight cases (65.9% were delivered at term uneventfully. Serious complications due to placental circulatory imbalance between twins occurred in about 6% of cases during the third trimester of pregnancy.

Older (but Not Younger) Siblings Facilitate False Belief Understanding.

Science.gov (United States)

Ruffman, Ted; Perner, Josef; Naito, Mika; Parkin, Lindsay; Clements, Wendy A.

1998-01-01

Four experiments and an analysis of pooled data from English and Japanese children show a linear increase in understanding false beliefs with number of older siblings; no such effect for children younger than 38 months; no helpful effect of younger siblings at any age; no effect of siblings' gender; and no helpful effect of siblings on a source…

Differential Parental Treatment, Sibling Relationships and Delinquency in Adolescence

Science.gov (United States)

Scholte, Ron H. J.; Engels, Rutger C. M. E.; de Kemp, Raymond A. T.; Harakeh, Zeena; Overbeek, Geertjan

2007-01-01

The present study examined the moderating effect of the quality of the sibling relationship on the longitudinal association of parental treatment with theft, vandalism, and violence in adolescence. Participants were 416 sibling pairs which were studied over a one-year period. The younger siblings were aged 13 to 15, the older siblings 14 to 17 at…

Chronic pain, depression and cardiovascular disease linked through a shared genetic predisposition: Analysis of a family-based cohort and twin study

Science.gov (United States)

Padmanabhan, Sandosh; Porteous, David J.; Burri, Andrea V.; Tanaka, Haruka; Williams, Frances M. K.

2017-01-01

Background Depression and chronic pain are the two most important causes of disability (Global Burden of Disease Study 2013). They occur together more frequently than expected and both conditions have been shown to be co-morbid with cardiovascular disease. Although shared socio-demographic risk factors (e.g. gender, deprivation) might explain the co-morbidity of these three conditions, we hypothesised that these three long-term, highly prevalent conditions co-occur and may be due to shared familial risk, and/or genetic factors. Methods and findings We employed three different study designs in two independent cohorts, namely Generation Scotland and TwinsUK, having standardised, validated questionnaire data on the three traits of interest. First, we estimated the prevalence and co-occurrence of chronic pain, depression and angina among 24,024 participants of a population-based cohort of extended families (Generation Scotland: Scottish Family Health Study), adjusting for age, gender, education, smoking status, and deprivation. Secondly, we compared the odds of co-morbidity in sibling-pairs with the odds in unrelated individuals for the three conditions in the same cohort. Lastly, examination of similar traits in a sample of female twins (TwinsUK, n = 2,902), adjusting for age and BMI, allowed independent replication of the findings and exploration of the influence of additive genetic (A) factors and shared (C) and non-shared (E) environmental factors predisposing to co-occurring chronic widespread pain (CWP) and cardiovascular disease (hypertension, angina, stroke, heart attack, elevated cholesterol, angioplasty or bypass surgery). In the Generation Scotland cohort, individuals with depression were more than twice as likely to have chronic pain as those without depression (adjusted OR 2·64 [95% CI 2·34–2·97]); those with angina were four times more likely to have chronic pain (OR 4·19 [3·64–4·82]); those with depression were twice as likely to have angina

Conjoined (Siamese) Twins in Zambia

African Journals Online (AJOL)

year-old Zambian multiparous mother gave birth to a set of twins with two heads ... (symmetric or mirror image) but one twin attached with an incomplete foetus is known as hetropagtrs. (asymmetrical). Thoracopagus twins (joined at the chest).

Ferrobielastic twinning in irradiated quartz

International Nuclear Information System (INIS)

Shiau, S.M.

1986-01-01

Cultured quartz is usually free from electrical twinning; however, it may occur if the seed crystal is twinned or if undue applied forces are exerted on the crystal. Ferrobielastic twinning was studied optically (photoelastic effect) and electrically (piezoelectric effect). At room temperature, twins were perceptible at stresses of about 2.l5 x 10 8 N/m 2 , and crystals switched from their original states to the alternative twin states at stresses about 5.0 x 10 8 N/m 2 (called coercive stress). The decrease in coercive stress with increasing temperature was observed, and these coercive stresses become very low as temperatures reach to 300 0 C. The effects of irradiation on the twinning in quartz were also studied. The presence of defects produced by irradiation was utilized to pin the domain wall motion. Both neutrons and gamma rays were employed. The stress required to nucleate an appreciable volume of twins is about twice as high for irradiated crystals than for those unirradiated. This result demonstrated that the irradiated crystals can tolerate higher stresses. However, the coercive stress for complete switch-over was not much different for irradiated and unirradiated crystals. It appears that the defects caused by irradiation eliminate the initial twinning events but do not affect switch-over

Voice similarity in identical twins.

Science.gov (United States)

Van Gysel, W D; Vercammen, J; Debruyne, F

2001-01-01

If people are asked to discriminate visually the two individuals of a monozygotic twin (MT), they mostly get into trouble. Does this problem also exist when listening to twin voices? Twenty female and 10 male MT voices were randomly assembled with one "strange" voice to get voice trios. The listeners (10 female students in Speech and Language Pathology) were asked to label the twins (voices 1-2, 1-3 or 2-3) in two conditions: two standard sentences read aloud and a 2.5-second midsection of a sustained /a/. The proportion correctly labelled twins was for female voices 82% and 63% and for male voices 74% and 52% for the sentences and the sustained /a/ respectively, both being significantly greater than chance (33%). The acoustic analysis revealed a high intra-twin correlation for the speaking fundamental frequency (SFF) of the sentences and the fundamental frequency (F0) of the sustained /a/. So the voice pitch could have been a useful characteristic in the perceptual identification of the twins. We conclude that there is a greater perceptual resemblance between the voices of identical twins than between voices without genetic relationship. The identification however is not perfect. The voice pitch possibly contributes to the correct twin identifications.

Psychoeducation for siblings of people with severe mental illness.

Science.gov (United States)

Sin, Jacqueline; Jordan, Cheryl D; Barley, Elizabeth A; Henderson, Claire; Norman, Ian

2015-05-08

Many people with severe mental illness (SMI) have siblings. Siblings are often both natural agents to promote service users' recovery and vulnerable to mental ill health due to the negative impact of psychosis within the family. Despite a wealth of research evidence supporting the effectiveness of psychoeducation for service users with SMI and their family members, in reducing relapse and promoting compliance with treatment, siblings remain relatively invisible in clinical service settings as well as in research studies. If psychoeducational interventions target siblings and improve siblings' knowledge, coping with caring and overall wellbeing, they could potentially provide a cost-effective option for supporting siblings with resulting benefits for service users' outcomes. To assess the effectiveness of psychoeducation compared with usual care or any other intervention in promoting wellbeing and reducing distress of siblings of people affected by SMI.The secondary objective was, if possible, to determine which type of psychoeducation is most effective. We searched the Cochrane Schizophrenia Group Trials Register and screened the reference lists of relevant reports and reviews (12th November 2013). We contacted trial authors for unpublished and specific data on siblings' outcomes. All relevant randomised controlled trials focusing on psychoeducational interventions targeting siblings of all ages (on their own or amongst other family members including service users) of individuals with SMI, using any means and formats of delivery, i.e. individual (family), groups, computer-based. Two review authors independently screened the abstracts and extracted data and two other authors independently checked the screening and extraction process. We contacted authors of trials to ascertain siblings' participation in the trials and seek sibling-specific data in those studies where siblings' data were grouped together with other participants' (most commonly other family members

One-dimensional pulse-flow modeling of a twin-scroll turbine

International Nuclear Information System (INIS)

Chiong, M.S.; Rajoo, S.; Romagnoli, A.; Costall, A.W.; Martinez-Botas, R.F.

2016-01-01

This paper presents a revised one-dimensional (1D) pulse flow modeling of twin-scroll turbocharger turbine under pulse flow operating conditions. The proposed methodology in this paper provides further consideration for the turbine partial admission performance during model characterization. This gives rise to significant improvement on the model pulse flow prediction quality compared to the previous model. The results show that a twin-scroll turbine is not operating at full admission throughout the in-phase pulse flow conditions. Instead, they are operating at unequal admission state due to disparity in the magnitude of turbine inlet flow. On the other hand, during out-of-phase pulse flow, a twin-scroll turbine is working at partial admission state for majority of the pulse cycle. An amended mathematical correlation in calculating the twin-scroll turbine partial admission characteristics is also presented in the paper. The impact of its accuracy on the pulse flow model prediction is explored. - Highlights: • Paper presents a 1D modeling for twin-scroll turbine under pulsating flow. • Predicted pulse pressure propagation is in good agreement with experimental data. • A methodology is proposed to consider the turbine partial admission performance. • Prediction shows twin-scroll turbine operates at unequal admission during in-phase flow. • During out-of-phase flow a twin-scroll turbine mainly operates at partial admission.

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…

Quality of Sibling Relationship and Substance Misuse: A Comparative Study

OpenAIRE

Anastasia Tsamparli; Elvisa Frrokaj

2016-01-01

The aim of the current study is to examine the quality of sibling relationship in families with a sibling with substance misuse (SSU) and compare the relationship to families with a sibling with no use (SNU). Thirty-six (36) families participated in the study (17 with SSU and 19 with SNU; N = 144). Semi-structured interviews were conducted with 40 siblings (20 SNU and 20 SSU; 18-31 years old) in order to qualitatively investigate the characteristics of the sibling relationship. The siblings w...

Parental Perceptions of Children's Sibling Relationships.

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Kramer, Laurie; Baron, Lisa A.

1995-01-01

Parental appraisals of their children's sibling relationships, and their standards for sibling relationships, were assessed. Although parents reported most concern about their children's Agonism and Rivalry/Competition, the largest discrepancies between parental standards and observations involved behaviors reflecting Warmth. Results endorse…

Sibling deidentification in the clinic: devil vs. angel.

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Schachter, F F

1985-09-01

A four-member family structure consisting of two siblings contrasting in personality (sibling deidentification) and each identified with a different parent (split-parent identification) was recently reported (15). In well-functioning families, this tetrad or quadrangle is wide-spread in the first pair of siblings in the family and tends to be more common in same-sex pairs, suggesting that sibling deidentification is designed to mitigate the relatively intense sibling rivalry characteristic of these pairs and hence to maintain family harmony. In this collated case report, deidentification is found to follow the same pattern in 39 clinic first pairs. However, contrasting attributes are varied and nonevaluative in nonclinic pairs but mainly "good-bad" in clinic pairs, with polarization extreme. Results suggest that nonclinic siblings negotiate their identity (being) much as they negotiate about possessions (having) and that negotiations are blocked in clinic pairs, freezing mythic devil or angel identity. Intervention is directed at dislodging this block.

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

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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.

Sibling advocates of people with intellectual disabilities.

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Ying Li, Eria Ping

2006-06-01

The aim of this study was to examine the experience of the first generation of sibling advocates in Hong Kong. A qualitative approach was adopted and six sibling advocates of people with intellectual disabilities from one non-government organization were interviewed. Data were analyzed using a constant comparative method and content analysis. Findings revealed that the six participants were reactive in the process of taking up the caregiver responsibility and they performed three functions: to advocate for more service provision, to improve service quality, and to facilitate communication between individual service units and family members of people with intellectual disabilities. All of the participants expressed that they needed support from service providers when they tried to function as the sibling advocates. Strategies to promote the involvement of siblings of people with intellectual disabilities as advocates are discussed and it is expected that more siblings of people with intellectual disabilities will be supported to have a higher level of involvement in advocacy.

Growth curves for twins in Slovenia.

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Bricelj, Katja; Blickstein, Isaac; Bržan-Šimenc, Gabrijela; Janša, Vid; Lučovnik, Miha; Verdenik, Ivan; Trojner-Bregar, Andreja; Tul, Nataša

2017-02-01

Abnormalities of fetal growth are more common in twins. We introduce the growth curves for monitoring fetal growth in twin pregnancies in Slovenia. Slovenian National Perinatal Information System for the period between 2002 and 2010 was used to calculate birth weight percentiles for all live born twins for each week from 22nd to 40th week. The calculated percentiles of birth weight for all live-born twins in Slovenia served as the basis for drawing 'growth' curves. The calculated growth curves for twins will help accurately diagnose small or large twin fetuses for their gestational age in the native central European population.

Prognostic and survival analysis of presbyopia: The healthy twin study

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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.

Deformation twinning: Influence of strain rate

Energy Technology Data Exchange (ETDEWEB)

Gray, G.T. III

1993-11-01

Twins in most crystal structures, including advanced materials such as intermetallics, form more readily as the temperature of deformation is decreased or the rate of deformation is increased. Both parameters lead to the suppression of thermally-activated dislocation processes which can result in stresses high enough to nucleate and grow deformation twins. Under high-strain rate or shock-loading/impact conditions deformation twinning is observed to be promoted even in high stacking fault energy FCC metals and alloys, composites, and ordered intermetallics which normally do not readily deform via twinning. Under such conditions and in particular under the extreme loading rates typical of shock wave deformation the competition between slip and deformation twinning can be examined in detail. In this paper, examples of deformation twinning in the intermetallics TiAl, Ti-48Al-lV and Ni{sub 3}A as well in the cermet Al-B{sub 4}C as a function of strain rate will be presented. Discussion includes: (1) the microstructural and experimental variables influencing twin formation in these systems and twinning topics related to high-strain-rate loading, (2) the high velocity of twin formation, and (3) the influence of deformation twinning on the constitutive response of advanced materials.

Sibling Relationships and Influences in Childhood and Adolescence

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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…

Fingerprint recognition with identical twin fingerprints.

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Tao, Xunqiang; Chen, Xinjian; Yang, Xin; Tian, Jie

2012-01-01

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.

The classical twin study and beyond

NARCIS (Netherlands)

Boomsma, D.I.; Busjahn, A.; Peltonen, L.

2002-01-01

Twin studies have been a valuable source of information about the genetic basis of complex traits. To maximize the potential of twin studies, large, worldwide registers of data on twins and their relatives have been established. Here, we provide an overview of the current resources for twin

Steady state performance evaluation of variable geometry twin-entry turbine

International Nuclear Information System (INIS)

Romagnoli, A.; Martinez-Botas, R.F.; Rajoo, S.

2011-01-01

This paper presents the results from an experimental investigation conducted on different turbine designs for an automotive turbocharger. The design progression was based on a commercial nozzleless unit that was modified into a variable geometry single and twin-entry turbine. The main geometrical parameters were kept constant for all the configurations and the turbine was tested under steady flow conditions. A significant depreciation in efficiency was measured between the single and twin-entry configuration due to the mixing effects. The nozzleless unit provides the best compromise in terms of performance at different speeds. The twin-entry turbine was also tested under partial and unequal admissions. Based on the test results a method to determine the swallowing capacity under partial admission given the full admission map is presented. The test results also showed that the turbine swallowing capacity under unequal admission is linked to the full admission case.

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

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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

Perceived Support in Sibling Relationships and Adolescent Adjustment

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Branje, Susan J. T.; Van Lieshout, Cornelis F. M.; Van Aken, Marcel A. G.; Haselager, Gerbert J. T.

2004-01-01

Background: Siblings may support each other, but also reveal fierce rivalry and mutual aggression. Supportive sibling relationships have been linked to the development of psychosocial competence of children. In the present longitudinal study, we will focus on the development of perceived support in sibling dyads and on the influence of sibling…

Young Children's Personal Accounts of Their Sibling Disputes

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Wilson, Anne E.; Smith, Melissa D.; Ross, Hildy S.; Ross, Michael

2004-01-01

We investigated children's personal representations of significant sibling conflicts. Forty pairs of siblings were interviewed separately about the same disputes. Although they described the same episodes, both older (M age = 7.0) and younger (M age = 4.4) siblings ascribed more serious transgressions to their opponents than to themselves. They…

Sibling Relationships Cognition in Japanese Female University Students

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Sawai, Misae; Kato, Daiki

2017-01-01

This study examined the factor structure of sibling relationships in Japanese female university students. Two hundred and fifteen Japanese female university students participated in this study. The Adult Sibling Relationship Scale (ASRQ, Stocker et al., 1997) was used to measure sibling relationship cognition. The model was constructed as a result…

High School and Beyond: Twins and Siblings' File Users' Manual, User's Manual for Teacher Comment File, Friends File Users' Manual.

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National Center for Education Statistics (ED), Washington, DC.

These three users' manuals are for specific files of the High School and Beyond Study, a national longitudinal study of high school sophomores and seniors in 1980. The three files are computerized databases that are available on magnetic tape. As one component of base year data collection, information identifying twins, triplets, and some non-twin…

Exotic quarks in Twin Higgs models

Energy Technology Data Exchange (ETDEWEB)

Cheng, Hsin-Chia [Department of Physics, University of California, Davis,One Shields Avenue, Davis, CA 95616 (United States); Jung, Sunghoon [School of Physics, Korea Institute for Advanced Study,85 Hoegiro, Dongdaemun-gu, Seoul 130-722 (Korea, Republic of); SLAC National Accelerator Laboratory,2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Salvioni, Ennio [Department of Physics, University of California, Davis,One Shields Avenue, Davis, CA 95616 (United States); Tsai, Yuhsin [Department of Physics, University of California, Davis,One Shields Avenue, Davis, CA 95616 (United States); Maryland Center for Fundamental Physics,Department of Physics, University of Maryland,College Park, MD 20742 (United States)

2016-03-14

The Twin Higgs model provides a natural theory for the electroweak symmetry breaking without the need of new particles carrying the standard model gauge charges below a few TeV. In the low energy theory, the only probe comes from the mixing of the Higgs fields in the standard model and twin sectors. However, an ultraviolet completion is required below ∼ 10 TeV to remove residual logarithmic divergences. In non-supersymmetric completions, new exotic fermions charged under both the standard model and twin gauge symmetries have to be present to accompany the top quark, thus providing a high energy probe of the model. Some of them carry standard model color, and may therefore be copiously produced at current or future hadron colliders. Once produced, these exotic quarks can decay into a top together with twin sector particles. If the twin sector particles escape the detection, we have the irreducible stop-like signals. On the other hand, some twin sector particles may decay back into the standard model particles with long lifetimes, giving spectacular displaced vertex signals in combination with the prompt top quarks. This happens in the Fraternal Twin Higgs scenario with typical parameters, and sometimes is even necessary for cosmological reasons. We study the potential displaced vertex signals from the decays of the twin bottomonia, twin glueballs, and twin leptons in the Fraternal Twin Higgs scenario. Depending on the details of the twin sector, the exotic quarks may be probed up to ∼ 2.5 TeV at the LHC and beyond 10 TeV at a future 100 TeV collider, providing a strong test of this class of ultraviolet completions.

Siblings of Individuals with an Autism Spectrum Disorder: Sibling Relationships and Wellbeing in Adolescence and Adulthood

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Orsmond, Gael I.; Kuo, Hsin-Yu; Seltzer, Marsha Mailick

2009-01-01

We investigated sibling relationships and wellbeing in adolescents and adults with a sibling with an autism spectrum disorder (ASD). Adolescents engaged in more shared activities than did adults. Adolescents reported greater social support, greater use of emotion-focused coping strategies, and less use of problem-focused coping than adults. In…

Sibling Relationships among Children with ADHD

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Mikami, Amori Yee; Pfiffner, Linda J.

2008-01-01

Objective: This study investigated the quality of sibling relationships among children with ADHD relative to those without ADHD. Additional analyses examined whether externalizing and internalizing problems comorbid with ADHD affected sibling relationships. Method: Participants were 77 children with ADHD and 14 nonproblem control children. Sibling…

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

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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.

Twin Higgs Asymmetric Dark Matter.

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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.

Psychosocial Well-being of Siblings of Adolescents with Anorexia Nervosa.

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van Langenberg, Tanja; Sawyer, Susan M; Le Grange, Daniel; Hughes, Elizabeth K

2016-11-01

Anorexia nervosa (AN) is often first diagnosed in the adolescent years. The treatment with the greatest evidence during this time is family-based treatment (FBT). In FBT, siblings are expected to attend treatment sessions; however, sibling well-being during this time has not been well researched. This study aimed to explore sibling well-being when the ill child was initially diagnosed with AN and after FBT had been completed. Eighty-five parents and 55 siblings of adolescents with AN completed the Strengths and Difficulties Questionnaire at diagnosis. In addition, 88 parents and 46 siblings completed the Strengths and Difficulties Questionnaire after finishing treatment. Mothers and fathers reported siblings to have lower levels of conduct problems in comparison with population norms. Mothers also reported lower levels of prosocial behaviours. Siblings reported higher levels of emotional difficulties and hyperactivity in comparison with their peers. There were no differences in reported psychosocial well-being of siblings between diagnosis and following FBT. Siblings of adolescents with AN have poorer psychosocial adjustment than their peers, both before and after FBT. Clinicians and parents are encouraged to be aware of sibling difficulties and seek additional support if required. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association.

A randomized controlled trial of a group intervention for siblings of children with cancer: Changes in symptoms of anxiety in siblings and caregivers.

Science.gov (United States)

Barrera, Maru; Atenafu, Eshetu G; Schulte, Fiona; Nathan, Paul C; Hancock, Kelly; Saleh, Amani

2018-06-01

This study assessed the effects of a group intervention-Siblings Coping Together (SibCT)-on siblings' and caregivers' anxiety symptoms compared to controls, and potential moderators. Seventy healthy siblings of children on or off treatment (7-16 y old, 41 males) participated in a randomized controlled trial (RCT) with 2 arms/groups: SibCT (n = 41) and an attention control (CG) (n = 34). Both groups had eight 2-hour weekly sessions. EG followed SibCT's educational, social, and problem-solving activities. CG had planned games and crafts. Siblings and caregivers self-reported on anxiety symptoms at baseline, intervention end, and 3 months later. Multivariable mixed model analyses examined the intervention effect over time, and potential moderators (gender, on/off ill child's treatment). No main effects of group or time were found in sibling scores. A group × gender interaction (P siblings reported less total anxiety symptoms than male siblings, with no significant gender differences in the control group. Caregivers' total anxiety symptoms declined over time (P siblings in SibCT reported less anxiety compared with caregivers of CG. There was no clear SibCT intervention effect. SibCT may benefit female siblings, and caregivers whose ill child is on active treatment. Contextual factors (gender) seem to influence psychosocial intervention in this population. Copyright © 2018 John Wiley & Sons, Ltd.

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

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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

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

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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.

Perceived Sibling Relationships and Adolescent Development.

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Yeh, Hsiu-Chen; Lempers, Jacques D.

2004-01-01

Utilizing longitudinal, 3-wave data collected from multiple informants (fathers, mothers, and target children) in 374 families, the potential effects of sibling relationships on adolescent development across early and middle adolescence were investigated. Adolescents who perceived their sibling relationships more positively at Time 1 tended to…

Don't forget the siblings: School-aged siblings of children presenting to mental health services show at-risk patterns of attachment.

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Kozlowska, Kasia; Elliott, Bronwen

2017-04-01

Family therapists understand that children presenting for treatment are often bearers of symptoms signalling relational problems within the family system. Rather than addressing the children's symptoms in isolation, family therapists typically take those relational problems as their starting point in therapy. This study used the School-aged Assessment of Attachment (SAA) to assess the self-protective (attachment) strategies of the siblings of children presenting for psychiatric evaluation and also of the siblings of control children drawn from the normative population. Siblings of children in the clinical group were much more likely than siblings of control children to use at-risk self-protective strategies and to have markers suggestive of unresolved loss or trauma. School-aged siblings were found to use a broad range of strategies, and the pattern of change from first born to later born involved either a reversal of strategy or a shift to a more complex strategy. The study highlights that siblings of children presenting to mental health services are significantly affected by family relational stress. A family systems approach to assessment, one that enquires about the wellbeing of all family members, will ensure that the emotional needs of siblings are also addressed during the therapy process.

Comparison of Attachment to Parents, Peers and Siblings in the Involved and Noninvolved Adolescents in Bullying

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حلیمه بیابانی علی آباد

2017-01-01

Full Text Available The aim of this study was to compare attachment to parents, peers and siblings among involved (bulling, victim, and bulling-victim and noninvolved in bullying in Yazd city. All of male and female students in the academic year 2013-2014 in Yazd included research population. A sample of 384 students were selected randomly through cluster sampling. Participants answered a sociometric questionnaire and also completed the Peer Relationship Questionnaire, the Inventory of Parents and Peer Attachment, and the Inventory of Siblings Attachment. Multivariate analysis (MANOVA indicated that there were significant differences in attachment to parents, peers and siblings between involved adolescents in bulling and noninvolved ones (p>0/0001. Regarding the attachment to parents, peers and siblings, noninvolved group scored higher than the involved groups. Also, among involved groups, the bully and the victim- bully groups received higher scores in attachment to mother prior to the peer attachment. Finally, the attachment to siblings in both groups was the lowest scores of attachment.

Assessing functional impairment in siblings living with children with disability.

Science.gov (United States)

Goudie, Anthony; Havercamp, Susan; Jamieson, Barry; Sahr, Timothy

2013-08-01

The purpose of this study was to empirically test if siblings of children with disability had higher levels of parent-reported behavioral and emotional functional impairment compared with a peer group of siblings residing with only typically developing children. This was a retrospective secondary analysis of data from the Medical Expenditure Panel Survey. We included only households with at least 2 children to ensure sibling relationships. Two groups of siblings were formed: 245 siblings resided in households with a child with disability and 6564 siblings resided in households with typically developing children. Parents responded to questions from the Columbia Impairment Scale to identify functional impairment in their children. On the basis of parent reports and after adjusting for sibling demographic characteristics and household background, siblings of children with disability were more likely than siblings residing with typically developing children to have problems with interpersonal relationships, psychopathological functioning, functioning at school, and use of leisure time (P siblings of children with disability classified with significant functional impairment was 16.0% at the first measurement period and 24.2% at the second (P siblings of typically developing children there was a smaller percentage increase from 9.5% to 10.3% (P mental health services and, as such, early assessment and interventions to limit increasing severity and short- to long-term consequences need to be addressed. Health care professionals need to consider a family-based health care approach for families raising children with disability.

Monozygotic twins with CAPN5 autosomal dominant neovascular inflammatory vitreoretinopathy

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Rowell HA

2012-12-01

Full Text Available Hannah A Rowell,1,2 Alexander G Bassuk,3,4 Vinit B Mahajan1,21Omics Laboratory, 2Department of Ophthalmology and Visual Sciences, 3Department of Pediatrics, 4Department of Neurology, University of Iowa, Iowa City, IA, USABackground: The purpose of this study was to describe the clinical findings in a set of monozygotic twins with autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV over a 23-year period.Methods: A pair of female twins were examined between 26 and 49 years of age. The concordance and discordance of their clinical features were determined. The CAPN5 gene was sequenced using genomic DNA.Results: Both twins of an affected father demonstrated Stage I ADNIV with mild vitreous cells and a negative b-wave on electroretinography. Genetic analysis confirmed a guanine to thymine nucleotide (c.728G>T, pArg243Leu mutation in the CAPN5 gene. Over the course of 23 years, each twin progressed to stage III disease, showing posterior uveitis, cystoid macular edema, intraocular fibrosis, early retinal neovascularization, retinal degeneration, and cataract. Disease progression varied moderately between each twin and was asymmetrical between eyes. Twin A had 20/70 and 20/125 in the right and left eye, respectively, and underwent vitrectomy surgery and intravitreal injections with bevacizumab for recurrent cystoid macular edema. Twin B maintained 20/20 and 20/40 in the right and left eye, respectively without intervention.Conclusion: There was asymmetry between the eyes and some discordance in the rate of disease progression in these monozygotic twins with ADNIV. The overall high disease concordance suggests genetic factors play a major role in clinical manifestations in CAPN5 vitreoretinopathy.Keywords: autosomal dominant neovascular inflammatory vitreoretinopathy, ADNIV, CAPN5, calpain-5, monozygotic twins

Neurodevelopmental outcome at 2 years in twin-twin transfusion syndrome survivors randomized for the Solomon trial.

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van Klink, Jeanine M M; Slaghekke, Femke; Balestriero, Marina A; Scelsa, Barbara; Introvini, Paola; Rustico, Mariangela; Faiola, Stefano; Rijken, Monique; Koopman, Hendrik M; Middeldorp, Johanna M; Oepkes, Dick; Lopriore, Enrico

2016-01-01

The preferred treatment for twin-twin transfusion syndrome is fetoscopic laser coagulation of inter-twin vascular anastomoses on the monochorionic placenta. Severe postoperative complications can occur when inter-twin vascular anastomoses remain patent including twin-anemia polycythemia sequence or recurrent twin-twin transfusion syndrome. To minimize the occurrence of residual anastomoses, a modified laser surgery technique, the Solomon technique, was developed in which the entire vascular equator is coagulated. In the Solomon randomized controlled trial (NTR1245), the Solomon technique was associated with a significant reduction in twin-anemia polycythemia sequence and recurrence of twin-twin transfusion syndrome when compared with the standard laser surgery technique. Although a significant improvement in perinatal outcome was shown after the Solomon technique, the clinical importance should also be ascertained with long-term follow-up evaluation of the surviving children. The purpose of this study was to compare the long-term neurodevelopmental outcome in surviving children with twin-twin transfusion syndrome who were included in the Solomon randomized trial and treated with either the Solomon technique or standard laser surgery technique. Routine standardized follow-up evaluation in survivors, at least 2 years after the estimated date of delivery, was performed at 2 of the 5 centers that participated in the Solomon trial: Buzzi Hospital Milan (Italy) and Leiden University Medical Center (The Netherlands). The primary outcome of this follow-up study was survival without long-term neurodevelopmental impairment at age 2 years. Neurodevelopmental impairment was defined as cerebral palsy, cognitive and/or motor development score of neurodevelopmental impairment) was detected in 95 of 141 cases (67%) in the Solomon group and in 99 of 146 cases (68%) in the standard group (P = .92). Neurodevelopmental impairment in long-term survivors who were included for follow

Low twinning rate and seasonal effects on twinning in a fertile population, the Hutterites

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Nonaka, K.; Miura, T.; Peter, K.

1993-09-01

This paper analyzes from the mid 18th century to 1987 the birth records of the “Dariusleut,” one of the three subgroups of the Hutterite population. The aim of this study is to describe several aspects of the twinning rate in a fertile population. The overall rate of twinning was 0.90%:103 twins among all 11492 maternities. The rate peaked at the 7th birth order and at the maternal age of 40 years and over. Until the mid 19th century when the Hutterites lived in Russia, the twinning rate was higher (1.5%), and it decreased during the migration period in the second half of the 19th century (0.7%). After the group had settled in the USA and Canada, the population maintained a twinning rate of 1.0% until 1965. After 1965 the rate decreased to 0.7%, partly due to a decline in fertility among women aged 30 years and over. There was a significant seasonal variation: the twinning rate decreased to 0.5% in May July compared to 1.2% for the other three seasons during the years up to 1965 ( P<0.01), while more recent mothers did not show such a seasonal variation. The incidence of twin births in this population seems to have been influenced by environmental factors, which would change their effect seasonally and secularly.

Associations Between Adiposity and Metabolic Syndrome Over Time: The Healthy Twin Study.

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Song, Yun-Mi; Sung, Joohon; Lee, Kayoung

2017-04-01

We evaluated the association between changes in adiposity traits including anthropometric and fat mass indicators and changes in metabolic syndrome traits including metabolic syndrome clustering and individual components over time. We also assessed the shared genetic and environmental correlations between the two traits. Participants were 284 South Korean twin individuals and 279 nontwin family members had complete data for changes in adiposity traits and metabolic syndrome traits of the Healthy Twin study. Mixed linear model and bivariate variance-component analysis were applied. Over a period of 3.1 ± 0.6 years of study, changes in adiposity traits [body mass index (BMI), waist circumference, total fat mass, and fat mass to lean mass ratio] had significant associations with changes in metabolic syndrome clustering [high blood pressure, high serum glucose, high triglycerides (TG), and low high-density lipoprotein cholesterol] after adjusting for intra-familial and sibling correlations, age, sex, baseline metabolic syndrome clustering, and socioeconomic factors and health behaviors at follow-up. Change in BMI associated significantly with changes in individual metabolic syndrome components compared to other adiposity traits. Change in metabolic syndrome component TG was a better predictor of changes in adiposity traits compared to changes in other metabolic components. These associations were explained by significant environmental correlations but not by genetic correlations. Changes in anthropometric and fat mass indicators were positively associated with changes in metabolic syndrome clustering and those associations appeared to be regulated by environmental influences.

Kinetic model for mechanical twinning and its application for intensive loading of metals

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Mayer Alexander

2015-01-01

Full Text Available In this report, we present our twinning model intended for simulation of the dynamic deformation of metals with low values of the stacking fault energy, as well as the results of application of the model to numerical simulation of intensive loading of metals. Generation of a twin is described as an appearance of a stacking fault with size more than some critical value, while growth of a twin is considered as a cooperative movement of partial dislocation along the stacking fault. The twin nucleation rate is expressed through the energy released due to annihilation of dislocations. Movement of partial dislocations in the course of twin growth passes under the action of elastic stress field and phonon drag. The surface energy of the growing twin continuously increases which leads to the appearance of an additional force. Application of this model allows us to investigate plastic response of metals at various dynamic loading conditions and initial defect structures. Influence of twinning at Taylor rod compaction experiments is analyzed including formation of the shape of the lateral surface.

Twin relationships of 5M modulated martensite in Ni-Mn-Ga alloy

International Nuclear Information System (INIS)

Li Zongbin; Zhang Yudong; Esling, Claude; Zhao Xiang; Zuo Liang

2011-01-01

Highlights: → We determine orientation relationships of 5M modulated martensite in NiMnGa alloy. → Accurate EBSD mapping is performed using monoclinic superstructure. → Four distinct variants mutually twin-related to each other are revealed. → Three twinning types and full twinning elements are identified. → Twin interfaces do coincide with respective twinning planes. - Abstract: For Ni-Mn-Ga ferromagnetic shape memory alloys, the characteristic features of modulated martensite (including the number/shape of constituent variants, the inter-variant orientation relationship and the geometrical distribution of variant interfaces) determine the attainability of the shape memory effect. In the present work, a comprehensive microstructural and crystallographic investigation has been conducted on a bulk polycrystalline Ni 50 Mn 28 Ga 22 alloy. As a first attempt, the orientation measurements by electron backscatter diffraction (EBSD) - using the precise information on the commensurate 5M modulated monoclinic superstructure (instead of the conventionally simplified non-modulated tetragonal structure) - were successfully performed to identify the crystallographic orientations on an individual basis. Consequently, the morphology of modulated martensite, the orientation relationships between adjacent variants and the characters of twin interfaces were unambiguously determined. With the thus-obtained full-featured image on the configuration of martensitic variants, the possibility of microstructural modification by proper mechanical 'training' was further discussed. This new effort makes it feasible to explore the crystallographic/microstructural correlations in modulated martensite with high statistical reliability, which in turn provides useful guidance for optimizing the microstructure and shape memory performance.

Relationship of Sibling Structure and Interaction to Categorization Ability. Final Report.

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Cicirelli, Victor G.; And Others

This study identified behaviors of sibling pairs interacting on a cognitive task and related these behaviors to sibling structure variables (age and sex of each sibling and age spacing between them) and to measure of cognitive abilities of the younger sibling. Subjects were 160 sibling pairs randomly selected from appropriate subpopulations of…

Perinatal outcome of singleton siblings born after assisted reproductive technology and spontaneous conception: Danish national sibling-cohort study.

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Henningsen, Anna-Karina Aaris; Pinborg, Anja; Lidegaard, Øjvind; Vestergaard, Christina; Forman, Julie Lyng; Andersen, Anders Nyboe

2011-03-01

To compare the perinatal outcome of singleton siblings conceived differently. National population-based registry study. Denmark, from 1994 to 2008. Pairs of siblings (13,692 pairs; n = 27,384 children) conceived after IVF, intracytoplasmatic sperm injection (ICSI), frozen embryo replacement (FER), or spontaneous conception subcategorized into five groups according to succession: [1] IVF-ICSI vs. spontaneous conception (n = 7,758), [2] IVF-ICSI vs. FER (n = 716), [3] FER vs. FER (n = 34), [4] IVF-ICSI vs. IVF-ICSI (n = 2,876), and [5] spontaneous conception vs. spontaneous conception (n = 16,000). Observations were obtained from national registries. Birth weight, gestational age, low birth weight (children compared with their spontaneously conceived siblings. FER children were 167 g (95% CI, 90-244] heavier than siblings born after replacement of fresh embryos. The difference in birth weight between firstborn and second born sibling depended on order of conception method. Higher risk of low birth weight with (odds ratio [OR], 1.4; 95%CI, 1.1-1.7] and preterm birth (OR, 1.3; 95% CI, 1.1-1.6] was observed in IVF/ICSI compared with spontaneous conception. When differentiating between order and mode of conception, it seems that assisted reproductive technology plays a role in mean birth weight and risk of low birth weight and preterm birth. Birth weight was higher in siblings born after FER compared with fresh embryos replacement. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

BENTUK PERILAKU SIBLING RIVALRY PADA ANAK KEMBAR BERDASARKAN PENGASUHAN ORANGTUA

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Herdian Herdian

2014-07-01

Full Text Available Penelitian ini bertujuan untuk menggambarkan bentuk perilaku sibling rivalry pada anak kembar berdasarkan pengasuhan orangtua yang terjadi. Penelitian ini menggunakan metode kualitatif, yang pengambilan datanya menggunakan wawancara serta observasi.Subjek penelitiannya adalah 4 pasang anak kembar dan 8 orang terdekat dengan subjek.Validitas data menggunakan teknik triangulasi data dengan sumber, yang berarti membandingkan dan mengecek balik derajat kepercayaan suatu informasi yang diperoleh melalui waktu dan alat berbeda.Analisis data dilakukan dengan bentuk interaktif.Temuan penelitiannya adalah, perilaku sibling rivalry terjadi karena perlakuan orangtua yang berbeda pada masing-masing anak kembar, selain itu dikarenakan cara orangtua dalam memperlakukan anak dalam menangani konflik yang terjadi pada anak kembar. Terdapat dua subjek yang mendapatkan perlakuan yang berbeda ketika berkelahi yaitu dengan membela salah satu anak kembar dikarenakan posisinya sebagai adik.Perlakuan yang berbeda lainnya terlihat pada salah satu subjek yaitu dengan memberikan uang saku yang berbeda. Penyebab sibling rivalry pada anak kembar lainnya hanya disebabkan oleh rebutan barang, baju yang tertukar serta pemberian barang oleh lingkungan sosial yang masing-masing subjek tidak mendapatkan barang yang sama. Bentuk perilaku sibling rivalry yangterjadi terbagi menjadi tiga aspek yaitu fisik, psikis, dan sosial.Aspek fisik bentuk perilakunya yaitu memukul, menendang, mencakar, menjambak, mencubit, dan meninju tembok.Aspek psikis bentuk perilakunya yaitu menangis, cemburu, rewel, iri, sebal, marah, dan usaha mencari perhatian dengan bersandar ke ibu serta berhias.Aspek sosial bentuk perilakunya yaitu mengganggu, mengejek dan bertengkar.Dari hasil tersebut dapat dikategorikan berdasarkan jenis kelamin, laki-laki yaitu meninju tembok, sedangkan perempuan menjambak, mencubit, usaha untuk mencari perhatian dengan bersandar ke ibu serta berhias. Kata kunci : Sibling Rivalry

Non-Random Sibling Cannibalism in the Marine Gastropod Crepidula coquimbensis.

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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.

Sibling rivalry and the new baby: anticipatory guidance and management strategies.

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Sawicki, J A

1997-01-01

Sibling rivalry can be found in many families and frequently creates a stressful and challenging situation for parents. The arrival of a new baby often causes older siblings to feel displaced, frustrated, angry, and even unloved. Age, gender, personality and temperament, and parental behavior are factors that appear to influence the degree to which sibling rivalry occurs. Common reactions of older siblings to the birth of a new baby include aggression toward the newborn, behavioral regression, and attention seeking behavior, as well as independence and maturity. Anticipatory guidance is recommended to help parents adequately prepare their older child for the arrival of a new sibling. Strategies for managing sibling rivalry include open parent-child communication, equal treatment of siblings, non-intervention in sibling conflicts, distraction, and separation. Parents can minimize feelings of jealousy between siblings by providing a supportive, nurturing environment that allows each child to feel secure and loved.

Coupling Damage-Sensing Particles to the Digitial Twin Concept

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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.

The Impact of First-Episode Psychosis on the Sibling Relationship.

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

2015-01-01

Research and clinical practice in first-episode psychosis (FEP) has predominantly focused on parents and partners and has neglected siblings needs. This study aims to characterize the sibling relationship in FEP and to examine the illness-related variables that influence this relationship. Survey methodology explored the experience of 157 siblings during the first 18 months of their brother or sister's treatment. The Adult Sibling Relationship Questionnaire was used to measure the warmth, conflict, and rivalry within the relationship. A series of multivariate regression analyses were conducted to determine the relationship between illness characteristics and sibling relationship. When the young person experiencing FEP had a period of untreated psychosis longer than six months, required more than one hospital admission, had persisting psychotic symptoms, continued to use substances, and/or had a history of physical violence, warmth within the sibling relationship deteriorated. Regression analysis revealed that a history of violence was a significant predictor of the warmth, conflict, and rivalry within the sibling relationship. Suicide attempts were a significant predictor of conflict. This study has established associations between the sibling relationship and illness-related variables. This study promotes consideration of the importance of including siblings in early intervention. Given the powerful role this relationship can have as a protective factor, this study could inform future interventions involving siblings.

Intra-family stressors among adult siblings sharing caregiving for parents.

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Ngangana, Pamela C; Davis, Bertha L; Burns, Dorothy P; McGee, Zina T; Montgomery, Arlene J

2016-12-01

The aim of this study was to describe a Neuman Systems Model-guided study of perceptions of family stressors experienced by adult siblings who share caregiving for their parents and the influence of these stressors on adult siblings' relationships. The task of providing informal care for disabled parents is often shared by adult siblings. Family stressors experienced as part of caregiving may affect the sibling relationship. A mixed-method study design was used. Data were collected during 2013-2014 from 84 adult sibling caregivers. Seventy-two caregivers provided quantitative data for the Lifespan Sibling Relationship Scale and the Zarit Burden Scale and 79 provided qualitative data for the open-ended question. Adult siblings experienced mild-to-moderate levels of burden from family stressors when they share parental caregiving. The amount of burden from intra-family stressors was negatively related to the adult sibling relationship. Beneficial and noxious stressors were evident in the participants' responses to an open-ended question. The health of the parents affected the lives of adult siblings in both negative and positive ways. Although the majority of the adult siblings expressed a willingness to care for their parent(s) in an attempt to reciprocate the care, they had received from them, challenges emerged from dealing with family stressors. © 2016 John Wiley & Sons Ltd.

Educational inequality in cardiovascular diseases: a sibling approach.

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Søndergaard, Grethe; Dalton, Susanne Oksbjerg; Mortensen, Laust Hvas; Osler, Merete

2018-02-01

Educational inequality in diseases in the circulatory system (here termed cardiovascular disease) is well documented but may be confounded by early life factors. The aim of this observational study was to examine whether the associations between education and all cardiovascular diseases, ischaemic heart disease and stroke, respectively, were explained by family factors shared by siblings. The study population included all individuals born in Denmark between 1950 and 1979 who had at least one full sibling born in the same period. Using Cox regression, data were analysed in conventional cohort and within-sibship analyses in which the association was examined within siblings discordant on education. Assuming that attenuation of associations in the within-sibship as compared with the cohort analyses would indicate confounding from factors shared within families. A lower educational status was associated with a higher risk of cardiovascular disease, ischaemic heart disease and stroke. All associations attenuated in the within-sibship analyses, in particular in the analyses on ischaemic heart disease before age 45 years. For instance, in the cohort analyses, the hazard rate of ischaemic heart disease among women less than 45 years who had a primary school education was 94% (hazard ratio 1.94 (1.78-2.12) higher than among those with a vocational education, while it attenuated to 51% (hazard ratio 1.51 (1.34-1.71)) in the within-sibship analysis. Confounding from factors shared by siblings explained the associations between education and the cardiovascular disease outcomes but to varying degrees. This should be taken into account when planning interventions aimed at reducing educational inequalities in the development of cardiovascular disease, ischaemic heart disease and stroke.

Association of prenatal exposure to benzodiazepines and child internalizing problems: A sibling-controlled cohort study.

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Ragnhild E Brandlistuen

Full Text Available During pregnancy, many women experience sleep problems and anxiety that require treatment. The long-term safety for the child of maternal benzodiazepine (BZD and z-hypnotic use during pregnancy remains controversial.We conducted a cohort and a sibling control study using data from the Norwegian Mother and Child Cohort Study. Data on use of BZD and z-hypnotics, internalizing and externalizing outcomes, and covariates were collected from mothers at gestational weeks 17 and 30 and when children were 0.5, 1.5, and 3 years of age. The total sample consisted of 71,996 children (19,297 siblings at 1.5 years and 55,081 children (13,779 siblings at 3 years. Short-term use was defined as use in one pregnancy period only. Long-term use was defined as use in two or more pregnancy periods. Linear full cohort random-effect and sibling-matched fixed-effect regression models were used to compare internalizing and externalizing behavior in children prenatally exposed compared to those unexposed in the full cohort of pregnancies accounting for family clusters, as well as within sibling clusters comparing pregnancies with discordant exposures. Propensity score (PS adjustment included variables on indication for use (sleep problems, symptoms of anxiety and depression and other potential confounding factors.Long-term prenatal exposure to BZD or z-hypnotics was associated with increased internalizing behavior in crude cohort analyses and at age 1.5 years after PS adjustment in sibling-matched fixed-effect models [β 0.60, 95% confidence interval 0.17-0.95]. Analyses on specific drug groups showed that prenatal exposure to BZD-anxiolytics was associated with increased internalizing problems at both 1.5 years [β 0.25, 0.01-0.49] and 3 years [β 0.26, 0.002-0.52] while exposure to z-hypnotics was not associated with any adverse outcomes after adjustment.The findings suggest a moderate association between BZD-anxiolytic exposure and child internalizing problems that is

Sibling experiences after a major childhood burn injury.

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Lehna, Carlee

2010-01-01

The purpose of this research project was to understand, primarily from the sibling perspective, the effect of a child's major burn injury on his or her sibling. A mixed method qualitative dominant design was implemented using the life story method for the qualitative portion. Additionally, the Sibling Relationship Questionnaire -Revised (SRQ-R) was used as a structured interview guide and for calculating scoring data to explore sibling relationship factors of warmth/closeness, rivalry, conflict, and relative status/power. Participants from 22 family cases (one or multiple family members) and 40 individuals were interviewed. To capture impact on the family over time, interviews began a minimum of two years post-burn. The central thematic pattern for the sibling relationship in families having a child with a major burn injury was that of normalization. Two components of normalization were described: areas of normalization and the process of adjustment. Areas of normalization were found in play and other activities, in school and work, and in family relations with siblings. The process of adjustment was varied and often gradual, involved school and work re-entry, and in some instances, seemed to change life perspective. Clinical implications in providing family-centered care can focus on promoting normalization by assessing and supporting siblings who may only be occasionally seen in the hospital or clinic.

Gratitude for help among adult friends and siblings.

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Rotkirch, Anna; Lyons, Minna; David-Barrett, Tamas; Jokela, Markus

2014-07-06

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.

Modelling the motion of {112-bar 2} twinning dislocations in the HCP metals

International Nuclear Information System (INIS)

Serra, A.; Bacon, D.J.

2005-01-01

Deformation twinning is important for plasticity of the hcp metals, but little is known about the dynamics of the mechanisms that control twin boundary motion. With the exception of the {112-bar 1} twin, atomic shuffles are required for glide of twinning dislocations and hence boundary movement is temperature-dependent. A computer method has been developed to simulate a step with dislocation character in a boundary with full periodicity in the boundary plane, i.e. along both the direction of the line of the defect and its direction of motion. It may be used to investigate the properties of such interfaces as the defects in them move over large distances. We explain the nature of the method and apply it to study the motion of twinning dislocations in the {112-bar 2} boundary as a function of applied stress and temperature. A new reaction at the boundary leading to the creation of a (c+a) crystal dislocation and a {112-bar 1} micro-twin is described

Sibling Kinnections: A Clinical Visitation Program

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Pavao, Joyce Maguire; St. John, Melissa; Cannole, Rebecca Ford; Fischer, Tara; Maluccio, Anthony; Peining, Suzanne

2007-01-01

The growing literature on sibling relationships throughout their lifespans is of great importance to those working in the child welfare system, and in adoption services in particular. Sibling bonds are important to all of us, but they are particularly vital to children from disorganized or dysfunctional families. These relationships assume even…

Siblings in the context of anorexia nervosa.

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Bachner-Melman, Rachel

2005-01-01

Sibling relationships may be relevant to the development of anorexia nervosa (AN), yet little research has focused on this aspect of the disorder. A narrative study of four women in various stages of recovery from AN is described and results relevant to sibling relationships are presented, enriched by published anecdotes and case studies. The anorexic interviewees described much antagonism and rivalry and little warmth and intimacy between themselves and their siblings. They seemed to feel they did not belong sufficiently in their families and other social settings despite a strong desire to belong. The sample is small, reports subjective and retrospective and no control group was included. It is suggested that anorexic girls often feel emotionally isolated from and misunderstood by siblings, who may have much to contribute to the process of therapy and recovery.

Psychological Adjustment of Siblings to a Child with Diabetes.

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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…

Reducing Sibling Conflict in Maltreated Children Placed in Foster Homes

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Linares, L. Oriana; Jimenez, Jessica; Nesci, Cristina; Pearson, Eva; Beller, Sarah; Edwards, Nancy; Levin-Rector, Alison

2016-01-01

Sibling aggression among maltreated children placed in foster homes is linked to other externalizing problems and placement disruption. The reduction of sibling conflict and aggression may be achieved via a multicomponent ecologically focused intervention for families in the foster care system. The focus of the study is to evaluate the feasibility and short-term effectiveness of a transtheoretical intervention model targeting sibling pairs and their foster parent that integrates family systems, social learning theory, and a conflict mediation perspective. In this pilot study, sibling pairs (N=22) and their foster parent were randomized into a three-component intervention (n=13) or a comparison (n=9) group. Promoting Sibling Bonds (PSB) is an 8-week prevention intervention targeting maltreated sibling pairs ages 5–11 years placed together in a foster home. The Siblings, Parent, and Joint components were delivered in a program package at the foster agency by a trained two-clinician team. Average attendance across program components was 73%. Outcomes in four areas were gathered at pre-and post-intervention: observed sibling interaction quality (positive and negative) including conflict during play, and foster parent reports of mediation strategies and sibling aggression in the foster home. At post-intervention, adjusting for baseline scores and child age, intervention pairs showed higher positive (p<.001) and negative (p<.05) interaction quality, and lower sibling conflict during play (p <.01) than comparison pairs. Foster parents in the intervention group reported a higher number of conflict mediation strategies than those in the comparison group (p <.001). Foster parents in the intervention group reported lower sibling physical aggression from the older toward the younger child than those in the comparison group (p <.05). Data suggest that the PSB intervention is a promising approach to reduce conflict and promote parental mediation which together may reduce

Siblings and Theory of Mind in Deaf Native Signing Children.

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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…

Maintaining Sibling Relationships for Children in Foster and Adoptive Placements.

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James, Sigrid; Monn, Amy R; Palinkas, Lawrence A; Leslie, Laurel K

2008-01-01

To better understand the nature of sibling relationships among children in foster or adoptive placement and the challenges and processes involved in maintaining these relationships, we conducted an exploratory analysis of data collected from semi-structured interviews with caregivers of 14 foster and adopted children in San Diego County. We identified three patterns of placement histories and living situations which appeared to impact the degree of contact maintained with siblings: (1) children who had never lived together and were not currently placed together; (2) children who at some point lived with or were placed together with their siblings, but were now separated from them; and (3) children who had lived with their siblings all their life and were placed together with at least some of their siblings at the time of the interview. Children's current living situations and placement histories, caregivers' experiences and perceptions of feasibility and desirability of sibling contact, and the sibling relationship itself are primary determinants in the development and maintenance of contact between siblings. Implications for child welfare policy and practice are discussed.