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Sample records for andidentical twins discordant

  1. Behavioral versus genetic determination of lipoproteins andidentical twins discordant for exercise

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Paul T.; Blanche, Patricia J.; Krauss, Ronald M.

    2004-06-01

    Lipoprotein and weight differences between vigorously active and sedentary MZ twins are used to: (1) estimate the effects of training while controlling for genotype; (2) estimate genetic concordance in the presence of divergent lifestyles.

  2. Discordant Epilepsy in Monozygous Twins

    OpenAIRE

    2001-01-01

    Twelve monozygotic twins, discordant for epilepsy, were analysed for nonhereditary etiological factors by clinical history, MRI, and quantitative brain volume studies at the Brain Research Institute, University of Melbourne, Victoria, Australia.

  3. Dichorionic twin pregnancy discordant for fetal anencephaly: a case report.

    Science.gov (United States)

    Taşcı, Yasemin; Karasu, Yetkin; Erten, Ozlem; Karadağ, Burak; Göktolga, Umit

    2012-01-01

    Dichorionic twin pregnancy discordant for fetal anencephaly is a serious condition that threatens the normal co-twin's life by causing polyhydramniosis, preterm labor and sudden death of one or both of the fetuses. We report a case of dichorionic twin pregnancy discordant for fetal anencephaly delivered at the 32(nd) week of gestation because of preterm labor and nonreassuring fetal monitoring. The aim of this case report is to summarize management options in this situation.

  4. Adult glucose metabolism in extremely birthweight-discordant monozygotic twins

    DEFF Research Database (Denmark)

    Frost, M; Petersen, I; Brixen, K

    2012-01-01

    Low birthweight (BW) is associated with increased risk of type 2 diabetes. We compared glucose metabolism in adult BW-discordant monozygotic (MZ) twins, thereby controlling for genetic factors and rearing environment.......Low birthweight (BW) is associated with increased risk of type 2 diabetes. We compared glucose metabolism in adult BW-discordant monozygotic (MZ) twins, thereby controlling for genetic factors and rearing environment....

  5. Cognitive function in unaffected twins discordant for affective disorder

    DEFF Research Database (Denmark)

    Christensen, Maj Vinberg; Kyvik, Kirsten Ohm; Kessing, Lars Vedel

    2006-01-01

    is associated with cognitive impairment. METHOD: In a cross-sectional high-risk case-control study, healthy monozygotic (MZ) and dizygotic (DZ) twins with (High-Risk twins) and without (the control group/Low-Risk twins) a co-twin history of affective disorder were identified through nationwide registers....... Cognitive performance of 203 High-Risk and Low-Risk twins was compared. RESULTS: Healthy twins discordant for unipolar disorder showed lower performance on almost all measures of cognitive function: selective and sustained attention, executive function, language processing and working and declarative memory......, and also after adjustment for demographic variables, subclinical symptoms and minor psychopathology. Healthy twins discordant for bipolar disorder showed lower performance on tests measuring episodic and working memory, also after adjustment for the above-mentioned covariables. The discrete cognitive...

  6. Epigenetic signature of birth weight discordance in adult twins

    DEFF Research Database (Denmark)

    Tan, Qihua; Nielsen, Morten Frost Munk; Heijmans, Bastiaan T

    2014-01-01

    Background: A low birth weight has been extensively related to poor adult health outcomes. Birth weight can be seen as a proxy for environmental conditions during prenatal development. Identical twin pairs discordant for birth weight provide an extraordinary model for investigating the association...... between birth weight and adult life health while controlling for not only genetics but also postnatal rearing environment. We performed an epigenome-wide profiling on blood samples from 150 pairs of adult monozygotic twins discordant for birth weight to look for molecular evidence of epigenetic signatures...... in association with birth weight discordance. Results: Our association analysis revealed no CpG site with genome-wide statistical significance (FDR twin...

  7. Perinatal risk factors and neonatal complications in discordant twins admitted to the neonatal intensive care unit

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-rui; LIU Jie; ZENG Chao-mei

    2013-01-01

    Background Many studies have shown a relationship between birth weight discordance and adverse perinatal outcomes.This study aimed to investigate the perinatal risk factors and neonatal complications of discordant twins who are admitted to the neonatal intensive care unit.Methods A total of 87 sets of twins were enrolled in this retrospective study,of which 22 sets were discordant twins and 65 sets were concordant twins.Binary Logistic regression analysis was used to identify the risk factors associated with the occurrence of discordant twins.The common neonatal complications of discordant twins were also investigated.Results Multivariate analysis showed that the use of assisted reproductive techniques,pregnancy-induced hypertension,and unequal placental sharing were risk factors for the occurrence of discordant twins.The incidence of small for gestational age infants and very low birth weight infants of discordant twins was significantly higher,while the birth weight of discordant twins was significantly lower than those of concordant twins.The duration of hospitalization of discordant twins was longer than that of concordant twins.The incidence of several neonatal complications,such as neonatal respiratory distress syndrome and intracranial hemorrhage,was higher in discordant twins than that in concordant twins.The percentage of those requiring pulmonary surfactant and mechanical ventilation was significantly higher in discordant twins than that in concordant twins.Conclusions Use of assisted reproductive techniques,pregnancy-induced hypertension,and unequal placental sharing are perinatal risk factors of discordant twins who are admitted to the neonatal intensive care unit.These infants are also much more likely to suffer from various neonatal complications,especially respiratory and central nervous system diseases.It is important to prevent the occurrence of discordant twins by decreasing these risk factors and timely treatment should be given to discordant

  8. Methylomic analysis of monozygotic twins discordant for childhood psychotic symptoms

    Science.gov (United States)

    Fisher, Helen L; Murphy, Therese M; Arseneault, Louise; Caspi, Avshalom; Moffitt, Terrie E; Viana, Joana; Hannon, Eilis; Pidsley, Ruth; Burrage, Joe; Dempster, Emma L; Wong, Chloe C Y; Pariante, Carmine M; Mill, Jonathan

    2015-01-01

    Childhood psychotic symptoms are associated with increased rates of schizophrenia, other psychiatric disorders, and suicide attempts in adulthood; thus, elucidating early risk indicators is crucial to target prevention efforts. There is considerable discordance for psychotic symptoms between monozygotic twins, indicating that child-specific non-genetic factors must be involved. Epigenetic processes may constitute one of these factors and have not yet been investigated in relation to childhood psychotic symptoms. Therefore, this study explored whether differences in DNA methylation at age 10 were associated with monozygotic twin discordance for psychotic symptoms at age 12. The Environmental Risk (E-Risk) Longitudinal Twin Study cohort of 2,232 children (1,116 twin pairs) was assessed for age-12 psychotic symptoms and 24 monozygotic twin pairs discordant for symptoms were identified for methylomic comparison. Children provided buccal samples at ages 5 and 10. DNA was bisulfite modified and DNA methylation was quantified using the Infinium HumanMethylation450 array. Differentially methylated positions (DMPs) associated with psychotic symptoms were subsequently tested in post-mortem prefrontal cortex tissue from adult schizophrenia patients and age-matched controls. Site-specific DNA methylation differences were observed at age 10 between monozygotic twins discordant for age-12 psychotic symptoms. Similar DMPs were not found at age 5. The top-ranked psychosis-associated DMP (cg23933044), located in the promoter of the C5ORF42 gene, was also hypomethylated in post-mortem prefrontal cortex brain tissue from schizophrenia patients compared to unaffected controls. These data tentatively suggest that epigenetic variation in peripheral tissue is associated with childhood psychotic symptoms and may indicate susceptibility to schizophrenia and other mental health problems. PMID:26479702

  9. Mitochondrial DNA Copy Number in Sleep Duration Discordant Monozygotic Twins

    DEFF Research Database (Denmark)

    Wrede, Joanna E; Mengel-From, Jonas; Buchwald, Dedra

    2015-01-01

    STUDY OBJECTIVES: Mitochondrial DNA (mtDNA) copy number is an important component of mitochondrial function and varies with age, disease, and environmental factors. We aimed to determine whether mtDNA copy number varies with habitual differences in sleep duration within pairs of monozygotic twins....... SETTING: Academic clinical research center. PARTICIPANTS: 15 sleep duration discordant monozygotic twin pairs (30 twins, 80% female; mean age 42.1 years [SD 15.0]). DESIGN: Sleep duration was phenotyped with wrist actigraphy. Each twin pair included a "normal" (7-9 h/24) and "short" (... twin. Fasting peripheral blood leukocyte DNA was assessed for mtDNA copy number via the n-fold difference between qPCR measured mtDNA and nuclear DNA creating an mtDNA measure without absolute units. We used generalized estimating equation linear regression models accounting for the correlated data...

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

    Directory of Open Access Journals (Sweden)

    Udo Jacob J

    2010-02-01

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

  11. Neonatal morbidity in growth-discordant monochorionic twins: comparison between the larger and the smaller twin.

    Science.gov (United States)

    Lopriore, Enrico; Sluimers, Carolien; Pasman, Suzanne A; Middeldorp, Johanna M; Oepkes, Dick; Walther, Frans J

    2012-08-01

    Fetal growth restriction in singletons has been shown to enhance fetal lung maturation and reduce the risk of respiratory distress syndrome due to increased endogenous steroid production. However, data on lung maturation in growth-discordant monochorionic (thus, identical) twins are lacking. Our objective was to compare the risk of severe neonatal morbidity between the larger and the smaller twin in monochorionic twins with birth weight discordance (BWD). We included in the study all consecutive monochorionic diamniotic pregnancies with severe BWD (≥25%) and two live-born twins delivered at our center (n=47 twin pairs). We compared the incidence of neonatal morbidity, particularly respiratory distress syndrome (RDS), and cerebral lesions between the larger and the smaller co-twin. The incidence of severe neonatal morbidity in the larger and smaller twin was 38% (18/47) and 19% (9/47), respectively (odds ratio (OR) 2.66, 95% confidence interval (CI) 0.94-7.44) and was due primarily to the higher incidence of RDS, 32% (15/47) and 6% (3/47), respectively (OR 6.88, 95% CI 1.66-32.83). In conclusion, this study shows that the larger twin in monochorionic twin pairs with BWD is at increased risk of severe neonatal morbidity, particularly RDS, compared to the smaller twin.

  12. Classification of discordant fetal growth may contribute to risk stratification in monochorionic twin pregnancies

    NARCIS (Netherlands)

    van Gemert, MJC; Vandenbussche, FPHA; Schaap, AHP; Zondervan, HA; Nikkels, PGJ; van Wijngaarden, WJ; van Zalen-Sprock, RM; Sollie-Szarynska, KM; Stoutenbeek, PH

    2000-01-01

    Objectives To determine whether classification of discordant growth between fetal twins allows risk stratification in monochorionic twin pregnancies. Methods In 12 twin-to-twin transfusion syndrome (TTTS) pregnancies and 12 cases that were suspected of developing the syndrome, fetal growth was deter

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

    Directory of Open Access Journals (Sweden)

    K. N. Venkateshwara Prasad

    2013-01-01

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

  14. Search for Genomic Alterations in Monozygotic Twins Discordant for Cleft Lip and/or Palate

    DEFF Research Database (Denmark)

    Kimani, Jane W; Yoshiura, Koh-Ichiro; Shi, Min

    2009-01-01

    consisting of 1,536 SNPs, to scan for genomic alterations in a sample of monozygotic twin pairs with discordant cleft lip and/or palate phenotypes. Paired analysis for deletions, amplifications and loss of heterozygosity, along with sequence verification of SNPs with discordant genotype calls did not reveal...... any genomic discordance between twin pairs in lymphocyte DNA samples. Our results demonstrate that postzygotic genomic alterations are not a common cause of monozygotic twin discordance for isolated cleft lip and/or palate. However, rare or balanced genomic alterations, tissue-specific events...

  15. What monozygotic twins discordant for phenotype illustrate about mechanisms influencing genetic forms of neurodegeneration

    NARCIS (Netherlands)

    Ketelaar, M. E.; Hofstra, R. M. W.; Hayden, M. R.

    2012-01-01

    As monozygotic (MZ) twins are believed to be genetically identical, discordance for disease phenotype between MZ twins has been used in genetic research to understand the contribution of genetic vs environmental factors in disease development. However, recent studies show that MZ twins can differ bo

  16. Chromosome 22q11.2 microdeletion in monozygotic twins with discordant phenotype and deletion size

    Directory of Open Access Journals (Sweden)

    Halder Ashutosh

    2012-03-01

    Full Text Available Abstract We report on a pair of male monozygotic twins with 22q11.2 microdeletion, discordant phenotype and discordant deletion size. The second twin had findings suggestive of DiGeorge syndrome, while the first twin had milder anomalies without any cardiac malformation. The second twin had presented with intractable convulsion, cyanosis and cardiovascular failure in the fourth week of life and expired on the sixth week of life, whereas the first twin had some characteristic facial appearance with developmental delay but no other signs of the 22q11.2 microdeletion syndrome including cardiovascular malformation. The fluorescence in situ hybridization (FISH analysis had shown a microdeletion on the chromosome 22q11.2 in both twins. The interphase FISH did not find any evidence for the mosaicism. The genomic DNA microarray analysis, using HumanCytoSNP-12 BeadChip (Illumina, was identical between the twins except different size of deletion of 22q11.2. The zygosity using HumanCytoSNP-12 BeadChip (Illumina microarray analysis suggested monozygosity. This observation indicates that altered size of the deletion may be the underlying etiology for the discordance in phenotype in monozygotic twins. We think early post zygotic events (mitotic non-allelic homologous recombination could have been played a role in the alteration of 22q11.2 deletion size and, thus phenotypic variability in the monozygotic twins.

  17. Genome-wide analysis of DNA methylation differences in muscle and fat from monozygotic twins discordant for type 2 diabetes

    DEFF Research Database (Denmark)

    Ribel-Madsen, Rasmus; Fraga, Mario F; Jacobsen, Stine

    2012-01-01

    Monozygotic twins discordant for type 2 diabetes constitute an ideal model to study environmental contributions to type 2 diabetic traits. We aimed to examine whether global DNA methylation differences exist in major glucose metabolic tissues from these twins.......Monozygotic twins discordant for type 2 diabetes constitute an ideal model to study environmental contributions to type 2 diabetic traits. We aimed to examine whether global DNA methylation differences exist in major glucose metabolic tissues from these twins....

  18. Salivary cortisol in unaffected twins discordant for affective disorder

    DEFF Research Database (Denmark)

    Vinberg, Maj; Bennike, Bente; Kyvik, Kirsten Ohm

    2008-01-01

    -sectional high-risk study. Healthy monozygotic (MZ) and dizygotic (DZ) twins with (High-Risk twins) and without (Low-Risk twins) a co-twin history of affective disorder were identified through nationwide registers. Awakening and evening salivary cortisol levels were compared between the 190 High- and Low......-Risk twins. The 109 High-Risk twins had significantly higher evening cortisol levels than the 81 Low-Risk MZ twins, also after adjustment for age, sex, and the level of subclinical depressive symptoms. No significant difference was found in awakening cortisol levels between High-Risk and Low-Risk twins....... In conclusion, a high genetic liability to affective disorder was associated with a higher evening cortisol level, but not with awakening cortisol level. Future prospective family, high-risk and twin studies are needed to decide whether abnormalities in the HPA axis can be identified as an endophenotype...

  19. Asthma discordance in twins is linked to epigenetic modifications of T cells.

    Directory of Open Access Journals (Sweden)

    R Scott Runyon

    Full Text Available T cells mediate the inflammatory responses observed in asthma among genetically susceptible individuals and have been suspected to be prone to epigenetic regulation. However, these relationships are not well established from past clinical studies that have had limited capacity to control for the effects of variable genetic predisposition and early environmental exposures. Relying on a cohort of monozygotic twins discordant for asthma we sought to determine if epigenetic modifications in T cells were associated with current asthma and explored whether such modifications were associated with second hand smoke exposures. Our study was conducted in a monozygotic twin cohort of adult twin pairs (n = 21 all discordant for asthma. Regulatory T cell (Treg and effector T cell (Teff subsets were assessed for levels of cellular function, protein expression, gene expression and CpG methylation within Forkhead box P3 (FOXP3 and interferon gamma-γ (IFNγ loci. Comparisons by asthma and current report of exposure to second hand smoke were made. Treg from asthmatic discordant twins demonstrated decreased FOXP3 protein expression and impaired Treg function that was associated with increased levels of CpG methylation within the FOXP3 locus when compared to their non-asthmatic twin partner. In parallel, Teff from discordant asthmatic twins demonstrated increased methylation of the IFNγ locus, decreased IFNγ expression and reduced Teff function when compared to Teff from the non-asthmatic twin. Finally, report of current exposure to second hand smoke was associated with modifications in both Treg and Teff at the transcriptional level among asthmatics. The results of the current study provide evidence for differential function of T cell subsets in monozygotic twins discordant for asthma that are regulated by changes in DNA methylation. Our preliminary data suggest exposure to second hand smoke may augment the modified T cell responses associated with asthma.

  20. DNA Methylation Changes in the IGF1R Gene in Birth Weight Discordant Adult Monozygotic Twins

    DEFF Research Database (Denmark)

    Tsai, Pei-Chien; Van Dongen, Jenny; Tan, Qihua;

    2015-01-01

    Low birth weight (LBW) can have an impact on health outcomes in later life, especially in relation to pre-disposition to metabolic disease. Several studies suggest that LBW resulting from restricted intrauterine growth leaves a footprint on DNA methylation in utero, and this influence likely...... persists into adulthood. To investigate this further, we performed epigenome-wide association analyses of blood DNA methylation using Infinium HumanMethylation450 BeadChip profiles in 71 adult monozygotic (MZ) twin pairs who were extremely discordant for birth weight. A signal mapping to the IGF1R gene (cg...... was particularly pronounced in older twins (random-effects meta-analysis p = .008, 98 older birth-weight discordant MZ twin pairs). The results suggest that severe intra-uterine growth differences (birth weight discordance >20%) are associated with methylation changes in the IGF1R gene in adulthood, independent...

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

    DEFF Research Database (Denmark)

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

    2017-01-01

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

  2. Dichorionic Diamniotic Twin Pregnancy Discordant for Bladder Exstrophy

    OpenAIRE

    William Tu; Jane Chueh; William Kennedy

    2009-01-01

    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.

  3. Dichorionic Diamniotic Twin Pregnancy Discordant for Bladder Exstrophy

    Directory of Open Access Journals (Sweden)

    William Tu

    2009-01-01

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

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

    Science.gov (United States)

    Segal, Nancy L

    2016-04-01

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

  5. Crown-rump length discordance in the first trimester: a predictor of adverse outcome in twin pregnancies?

    DEFF Research Database (Denmark)

    Johansen, Mathias; Oldenburg, A.; Rosthøj, Susanne;

    2014-01-01

    OBJECTIVES: To evaluate the usefulness of first-trimester crown-rump length (CRL) discordance in predicting adverse outcome in twin pregnancies. METHODS: This retrospective study included a large cohort retrieved from local ultrasound databases at 14 obstetric departments in Denmark, comprising all...... twin pregnancies with two live fetuses scanned between 11 and 14 weeks' gestation during the period 1 January 2004 to 31 December 2006. The association between CRL discordance ≥ 10 % and adverse outcome was evaluated. RESULTS: Among 1993 twin pregnancies, 1733 were dichorionic (156 (9%) discordant......; 1577 (91%) concordant) and 260 were monochorionic (32 (12%) discordant; 228 (88%) concordant). In dichorionic twin pregnancies we found an association between CRL discordance ≥ 10% and preterm delivery before 34 weeks' gestation (P=0.007), birth weight discordance (P=0.001) and mean birth weight (P=0...

  6. Personality traits in unaffected twins discordant for affective disorder

    DEFF Research Database (Denmark)

    Vinberg, M; Kyvik, Kirsten Ohm; Mortensen, E L

    2007-01-01

    ) and without (the control group/low-risk twins) a co-twin history of affective disorder were identified. Personality traits were compared for a total of 211 high-risk and low-risk twins. RESULTS: In univariate analyses, the high-risk twins had a higher level of neuroticism than the control twins (P = 0.......03). In multivariate analyses, a high genetic liability to affective disorder was not significantly associated with neuroticism but correlated to sex, minor psychopathology and recent life events. CONCLUSION: A high genetic liability to affective disorder showed an association with neuroticism, but the association...

  7. Birth weight discordant twins have increased prenatal mortality and neonatal morbidity: an analysis of 1,132 twins

    Directory of Open Access Journals (Sweden)

    Sara Domingues

    2015-02-01

    Full Text Available Background: Multiple pregnancies have increased significantly over the past decades. Birth weight discordance (BWD is a common problem between twins, but its association with an increased morbidity and mortality is still unclear. The aim of this study was to determine the frequency of BWD among twins and to evaluate its impact on perinatal morbidity.Methods: Retrospective study of 1,132 twins born in a tertiary perinatal center, over a period of 8 years (2003-2010, that were divided in two groups: concordant (intrapair birth weight difference ≤ 20% or discordant (> 20%. The two groups were compared in terms of epidemiological and obstetric data, mode of delivery, perinatal morbidity and mortality.Results: During the study period, multiple gestation occurred in 2% of cases, of which 96% were twins. BWD was found in 212 (19% twins. Multivariate analysis demonstrated that maternal age ≥ 35 years and hypoxic-ischemic placental infarction were risk factors for the occurrence of BWD. The discordant group showed a significantly higher incidence of congenital skeletal and central nervous system malformations, a higher rate of hospitalization in the neonatal intensive care unit and a longer duration of hospitalization. The percentage of those requiring assisted ventilation, pulmonary surfactant, parenteral nutrition and central venous catheters was significantly higher in the discordant group compared with the concordant one. The rate of stillbirth was significantly higher in the discordant group (3% versus 1%; mortality was also higher (3% versus 2%, but this difference was not statistically significant (p = 0.405.Conclusion: BWD was associated with increased prenatal mortality and neonatal morbidity. Diagnosis and management of pregnant women with this fetal condition in tertiary perinatal centers may improve the prognosis of these infants.

  8. Discordance of oral-facial-digital syndrome type 1 in monozygotic twin girls.

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    Shotelersuk, V; Tifft, C J; Vacha, S; Peters, K F; Biesecker, L G

    1999-09-17

    The oral-facial-digital syndrome type 1 (OFD1) includes limb, facial, intraoral malformations and the gene for the disorder was recently mapped to Xp22.3-p22.2. We report on monozygotic twin girls discordant for OFD1. Monozygosity is supported by placental pathology (monochorionic diamniotic) and molecular studies with probability of dizygosity twin has oral cavity abnormalities including median cleft lip, cleft palate, lobulated hamartomatous tongue, aberrant hyperplastic oral frenula, alveolar notches, and absent lateral incisors. Facial manifestations include telecanthus, hypoplastic alae nasi, and transient neonatal facial milia. The patient also has short and deviated fingers with partial cutaneous syndactyly. At 10 years, she has not had central nervous system or kidney problems. X-inactivation study revealed similar X-inactivation patterns in the lymphoblasts of both twins. We conclude that skewed X-inactivation is an unlikely cause for the discordance, which is more likely due to a postzygotic mutation in the affected twin.

  9. Changes in the pattern of DNA methylation associate with twin discordance in systemic lupus erythematosus

    Science.gov (United States)

    Javierre, Biola M.; Fernandez, Agustin F.; Richter, Julia; Al-Shahrour, Fatima; Martin-Subero, J. Ignacio; Rodriguez-Ubreva, Javier; Berdasco, Maria; Fraga, Mario F.; O'Hanlon, Terrance P.; Rider, Lisa G.; Jacinto, Filipe V.; Lopez-Longo, F. Javier; Dopazo, Joaquin; Forn, Marta; Peinado, Miguel A.; Carreño, Luis; Sawalha, Amr H.; Harley, John B.; Siebert, Reiner; Esteller, Manel; Miller, Frederick W.; Ballestar, Esteban

    2010-01-01

    Monozygotic (MZ) twins are partially concordant for most complex diseases, including autoimmune disorders. Whereas phenotypic concordance can be used to study heritability, discordance suggests the role of non-genetic factors. In autoimmune diseases, environmentally driven epigenetic changes are thought to contribute to their etiology. Here we report the first high-throughput and candidate sequence analyses of DNA methylation to investigate discordance for autoimmune disease in twins. We used a cohort of MZ twins discordant for three diseases whose clinical signs often overlap: systemic lupus erythematosus (SLE), rheumatoid arthritis, and dermatomyositis. Only MZ twins discordant for SLE featured widespread changes in the DNA methylation status of a significant number of genes. Gene ontology analysis revealed enrichment in categories associated with immune function. Individual analysis confirmed the existence of DNA methylation and expression changes in genes relevant to SLE pathogenesis. These changes occurred in parallel with a global decrease in the 5-methylcytosine content that was concomitantly accompanied with changes in DNA methylation and expression levels of ribosomal RNA genes, although no changes in repetitive sequences were found. Our findings not only identify potentially relevant DNA methylation markers for the clinical characterization of SLE patients but also support the notion that epigenetic changes may be critical in the clinical manifestations of autoimmune disease. PMID:20028698

  10. Is there a genetic basis for Fuchs' heterochromic uveitis? Discordance in monozygotic twins.

    OpenAIRE

    Jones, N. P.; Read, A P

    1992-01-01

    One pair, and probably two pairs, of monozygotic twins are reported with discordance for Fuchs' heterochromic uveitis (FHU). Regular Mendelian inheritance of this disease is now proved to be impossible. The heritability of FHU is low and may be zero. The possibility of any genetic predisposition to the disease and its association with 'simple' heterochromia are discussed.

  11. Discordant sex in monozygotic XXY/XX twins: a case report.

    Science.gov (United States)

    Tachon, G; Lefort, G; Puechberty, J; Schneider, A; Jeandel, C; Boulot, P; Prodhomme, O; Meyer, P; Taviaux, S; Touitou, I; Pellestor, F; Geneviève, D; Gatinois, V

    2014-12-01

    We report a case of discordant phenotypic sex in monozygotic twins mosaic 47,XXY/46,XX: monozygotic heterokaryotypic twins. The twins presented with cognitive and comprehension delay, behavioural and language disorders, all symptoms frequently reported in Klinefelter syndrome. Molecular zygosity analysis with several markers confirmed that the twins are in effect monozygotic (MZ). Array comparative genomic hybridization found no evidence for the implication of copy number variation in the phenotypes. Ultrasound scans of the reproductive organs revealed no abnormalities. Endocrine tests showed a low testosterone level in Twin 1 (male phenotype) and a low gonadotrophin level in Twin 2 (female phenotype) which, combined with the results from ultrasound examination, provided useful information for potentially predicting the future fertility potential of the twins. Blood karyotypes revealed the presence of a normal 46,XX cell line and an aneuploïd 47,XXY cell line in both patients. Examination of the chromosome constitutions of various tissues such as blood, buccal smear and urinary sediment not surprisingly showed different proportions for the 46,XX and 47,XXY cell lines, which most likely explains the discordant phenotypic sex and mild Klinefelter features. The most plausible underlying biological mechanism is a post-zygotic loss of the Y chromosome in an initially 47,XXY zygote. This would result in an embryo with both 46,XX and 47,XXY cells lines which could subsequently divide into two monozygotic embryos through a twinning process. The two cell lines would then be distributed differently between tissues which could result in phenotypic discordances in the twins. These observations emphasize the importance of regular paediatric evaluations to determine the optimal timing for fertility preservation measures and to detect new Klinefelter features which could appear throughout childhood in the two subjects.

  12. Discordance for Cri du Chat Syndrome in a dichorionic–diamniotic twin pregnancy

    Directory of Open Access Journals (Sweden)

    Mireia González-Comadran

    2015-07-01

    Full Text Available We report on the prenatal diagnosis through array CGH of a dichorionic–diamniotic (DC/DA twins discordant for Cri du Chat Syndrome. Structural anomalies on one of the twins lead to amniotic fluid sampling, which revealed a partial deletion on the short arm of the chromosome 5. Selective feticide of the affected twin was performed at 34 + 1 weeks' and elective Cesarean section at 37 + 2 weeks. Postnatal cytogenetic analysis confirmed pre-natal genetic findings.

  13. Quality of life in unaffected twins discordant for affective disorder

    DEFF Research Database (Denmark)

    Vinberg, Maj; Bech, Per; Kyvik, Kirsten Ohm

    2006-01-01

    BACKGROUND: The disability and hardship associated with affective disorder is shared by the family members of affective patients and might affect the family member's quality of life. METHOD: In a cross-sectional, high-risk, case-control study, monozygotic (MZ) and dizygotic (DZ) twins with (High......-Risk twins) and without (the control group/Low-Risk twins) a co-twin history of affective disorder were identified through nationwide registers. The aim of the present study was to investigate the hypothesis that a genetic liability to affective disorder is associated with a lower perception of quality...... for the effect of subclinical anxiety and depressive symptoms, the differences were significant on the domain environment and total WHOQoL-BREF and marginally significant on the domain physical health and overall quality of life. LIMITATIONS: It is not possible from the cross-sectional analyses to distinguish...

  14. Psychiatric outcomes of bullying victimization: A study of discordant monozygotic twins

    Science.gov (United States)

    Silberg, Judy L.; Copeland, William; Linker, Julie; Moore, Ashlee A.; Roberson-Nay, Roxann; York, Timothy P.

    2016-01-01

    Background Bullying victimization in childhood is associated with a broad array of serious mental health disturbances, including anxiety, depression, and suicidal ideation and behavior. The key goal of this study was to evaluate whether bullying victimization is a true environmental risk factor for psychiatric disturbance using data from 145 bully-discordant monozygotic (MZ) juvenile twin pairs from the Virginia Twin Study of Adolescent Behavioral Development (VTSABD) and their follow-up into young adulthood. Method Since MZ twins share an identical genotype and familial environment, a higher rate of psychiatric disturbance in a bullied MZ twin compared to their non-bullied MZ co-twin would be evidence of an environmental impact of bullying victimization. Environmental correlations between being bullied and the different psychiatric traits were estimated by fitting structural equation models to the full sample of MZ and DZ twins (N = 2824). Environmental associations were further explored using the longitudinal data on the bullying-discordant MZ twins. Results Being bullied was associated with a wide range of psychiatric disorders in both children and young adults. The analysis of data on the MZ-discordant twins supports a genuine environmental impact of bullying victimization on childhood social anxiety [odds ratio (OR) 1.7], separation anxiety (OR 1.9), and young adult suicidal ideation (OR 1.3). There was a shared genetic influence on social anxiety and bullying victimization, consistent with social anxiety being both an antecedent and consequence of being bullied. Conclusion Bullying victimization in childhood is a significant environmental trauma and should be included in any mental health assessment of children and young adults. PMID:26979565

  15. Recurrence risk for offspring of twins discordant for oral cleft: a population-based cohort study of the Danish 1936-2004 cleft twin cohort

    DEFF Research Database (Denmark)

    Grosen, Dorthe; Bille, Camilla; Pedersen, Jacob Krabbe;

    2010-01-01

    Our objective in this Danish population-based cohort study was to estimate the recurrence risk of isolated oral cleft (OC) for offspring of the unaffected co-twins of OC discordant twin pairs and to compare this risk to the recurrence risk in the offspring of the affected co-twin as well...... as to the risk in the background population. During 1936-2004, 207 twin pairs were ascertained, among whom at least one twin had an OC. The index persons were twins discordant for OC who had children (N=117), and their offspring (N=239). The participants were ascertained by linkage between The Danish Facial...... Cleft Database, The Danish Twin Registry and The Danish Civil Registration System. In the study OC recurrence risk for offspring of the affected and unaffected twin and relative risk were compared to the background prevalence. We found that among 110 children of the 54 OC affected twins, two (1...

  16. Monozygotic twins with 45,X/46,XY mosaicism discordant for phenotypic sex.

    Science.gov (United States)

    Costa, T; Lambert, M; Teshima, I; Ray, P N; Richer, C L; Dallaire, L

    1998-01-06

    We report on two sets of monozygotic twins (MZTs) discordant for phenotypic sex ascertained at birth when the female twin was noted to have signs of the Ullrich-Turner syndrome. Cytogenetic investigations on the female of the first pair showed 45,X/46,XY mosaicism in lymphocytes but fibroblasts grown from two skin biopsies at separate sites and from gonadal tissue showed only 45,X cells. The male showed mosaicism in both blood lymphocytes and skin fibroblasts. In the second family, both twins also showed mosaicism in lymphocytes. The female had a 45,X karyotype in fibroblasts from skin and gonadal tissue, but in contrast to the first family, the male twin had a normal male karyotype in fibroblasts from skin biopsy and from connective tissue adjacent to the vas deferens. Discordant phenotypic sex in monozygotic twins is rare. As in our cases, the nine previously reported sets of MZTs all had mosaicism for sex chromosome abnormalities. A mitotic error leading to the loss of a Y chromosome prior to, accompanying, or following the twinning process would account for the reported combinations of karyotypes.

  17. Discordant tooth agenesis and peg-shaped in a pair of monozygotic twins: Clinical and molecular study.

    Science.gov (United States)

    Antunes, Lívia Azeredo Alves; Küchler, Erika Calvano; Costa, Marcelo de Castro; Antunes, Leonardo Santos; Granjeiro, José Mauro

    2013-11-01

    The present report aimed to study an uncommon case of a pair of twins that presented a discordant dental phenotype. Family investigation, clinical, radiographic examination and molecular analysis were performed in both girls. Molecular analysis confirmed the monozygosity by deoxyribonucleic acid chip technology. One twin presented tooth agenesis in left upper lateral incisor and peg-shaped on the contra lateral side while the other twin had no dental alterations. The dental casts study employed digital caliper to compare morphological dimensions and showed alteration only in peg-shaped tooth. In conclusion, this study provide support that one or more mutated gene could cause discordances in dental phenotype in these monozygotic twins.

  18. Low birth weight is associated with NIDDM in discordant monozygotic and dizygotic twin pairs

    DEFF Research Database (Denmark)

    Poulsen, P; Vaag, Allan; Kyvik, K O;

    1997-01-01

    Previous studies have demonstrated an association between low weight at birth and risk of later development of non-insulin-dependent diabetes mellitus (NIDDM). It is not known whether this association is due to an impact of intrauterine malnutrition per se, or whether it is due to a coincidence....... Furthermore, monozygotic (MZ) twins have identical genotypes. Original midwife birth weight record determinations were traced in MZ and dizygotic (DZ) twins discordant for NIDDM. Birth weights were lower in the NIDDM twins (n = 2 x 14) compared with both their identical (MZ; n = 14) and non-identical (DZ; n...... = 14) non-diabetic co-twins, respectively (MZ: mean +/- SEM 2634 +/- 135 vs 2829 +/- 131 g, p

  19. Epigenome-wide association study on identical twins discordant for birth weight

    DEFF Research Database (Denmark)

    Tan, Qihua; Nielsen, Morten Frost Munk; Christiansen, Lene

    induces persistent epigenetic modification detectable at adult ages, we performed a genome-wide DNA methylation profiling in peripheral blood of 150 pairs of identical Danish twins discordant for birth weight using the Illumina Infinium HumanMethylation450 BeadChip featuring 485,000 CpG sites across...... the genome. After quality control and data preprocessing using free R package minfi, data were analysed by a mixed effects model including fixed effect variables such as birth weight difference, age and sex of twin pairs; random effect variables such as batch, well, and sample position on the array, etc....... Statistical analysis revealed 12 probes with p valuetwins is not associated...

  20. Monochorionic and dichorionic twin pregnancies discordant for fetal anencephaly: a systematic review of prenatal management options.

    Science.gov (United States)

    Lust, Annelies; De Catte, Luc; Lewi, Liesbeth; Deprest, Jan; Loquet, Philippe; Devlieger, Roland

    2008-04-01

    The aim of this study was to evaluate the effect of selective feticide (SF) compared to expectant management (EM) on perinatal outcome in dichorionic and monochorionic twins discordant for anencephaly. For this purpose, we conducted a systematic review of literature and added ten unpublished cases. As a result, we found that in dichorionic twins, mean gestational age (GA) at birth in the SF group was 38.0 weeks versus 34.9 weeks (P = 0.0002). Mean birth weight was 2922 g in the SF group versus 2474 g (P = 0.03). In monochorionic twins, mean GA at birth was 35.2 weeks versus 32.7 weeks (P = 0.1). Mean birth weight was 2711 g versus 1667 g (P = 0.0001). We conclude that while SF does not reduce perinatal mortality, it does result in significantly longer gestations and higher birth weight, and appears to be the management of choice in dichorionic twins discordant for anencephaly. In monochorionic twins, SF also increases birth weight, but in view of the complexity of this group, no clear recommendations can be made.

  1. Differentially Methylated DNA Regions in Monozygotic Twin Pairs Discordant for Rheumatoid Arthritis

    DEFF Research Database (Denmark)

    Svendsen, Anders J; Gervin, Kristina; Lyle, Robert;

    2016-01-01

    OBJECTIVES: In an explorative epigenome-wide association study (EWAS) to search for gene independent, differentially methylated DNA positions and regions (DMRs) associated with rheumatoid arthritis (RA) by studying monozygotic (MZ) twin pairs discordant for RA. METHODS: Genomic DNA was isolated......: We identified several differentially methylated regions associated with RA, which may represent environmental effects or consequences of the disease and plausible biological pathways pertinent to the pathogenesis of RA....

  2. Metabolome and fecal microbiota in monozygotic twin pairs discordant for weight: a Big Mac challenge.

    Science.gov (United States)

    Bondia-Pons, Isabel; Maukonen, Johanna; Mattila, Ismo; Rissanen, Aila; Saarela, Maria; Kaprio, Jaakko; Hakkarainen, Antti; Lundbom, Jesper; Lundbom, Nina; Hyötyläinen, Tuulia; Pietiläinen, Kirsi H; Orešič, Matej

    2014-09-01

    Postprandial responses to food are complex, involving both genetic and environmental factors. We studied postprandial responses to a Big Mac meal challenge in monozygotic co-twins highly discordant for body weight. This unique design allows assessment of the contribution of obesity, independent of genetic liability. Comprehensive metabolic profiling using 3 analytical platforms was applied to fasting and postprandial serum samples from 16 healthy monozygotic twin pairs discordant for weight (body mass index difference >3 kg/m(2)). Nine concordant monozygotic pairs were examined as control pairs. Fecal samples were analyzed to assess diversity of the major bacterial groups by using 5 different validated bacterial group specific denaturing gradient gel electrophoresis methods. No differences in fecal bacterial diversity were detected when comparing co-twins discordant for weight (ANOVA, Pfasting state, but their levels converged postprandially (paired t tests, FDR q<0.05). We also found that specific bacterial groups were associated with postprandial changes of specific metabolites. Our findings underline important roles of genetic and early life factors in the regulation of postprandial metabolite levels.

  3. College-age twins: university admission policies / twin research: birth weight and neuromotor performance; transfusion syndrome markers; vanishing twins and fetal sex determination; mz twin discordance for wilson's disease / media: big at birth; planned separation of conjoined twins; x factor twins; Cinema: the identical.

    Science.gov (United States)

    Segal, Nancy L

    2014-12-01

    There is a lack of research findings addressing the unique college admissions issues faced by twins and other multiples. The advantages and disadvantage twins face, as reported by college administrators, twins and families are reviewed. Next, recent research addressing twins' birth weight and neuromotor performance, transfusion syndrome markers, the vanishing twin syndrome and monozygotic (MZ) twin discordance for Wilson's disease is described. News items concerning the birth of unusually large twins, the planned separation of conjoined twins, twin participants in the X Factor games and a film, The Identical, are also summarized.

  4. Discordant tooth agenesis and peg-shaped in a pair of monozygotic twins: Clinical and molecular study

    OpenAIRE

    Lívia Azeredo Alves Antunes; Erika Calvano Küchler; Marcelo de Castro Costa; Leonardo Santos Antunes; José Mauro Granjeiro

    2013-01-01

    The present report aimed to study an uncommon case of a pair of twins that presented a discordant dental phenotype. Family investigation, clinical, radiographic examination and molecular analysis were performed in both girls. Molecular analysis confirmed the monozygosity by deoxyribonucleic acid chip technology. One twin presented tooth agenesis in left upper lateral incisor and peg-shaped on the contra lateral side while the other twin had no dental alterations. The dental casts study employ...

  5. Candidate region linkage analysis in twins discordant or concordant for depression symptomatology

    DEFF Research Database (Denmark)

    Christiansen, Lene; Tan, Q; Kruse, T A

    2009-01-01

    Genetic risk factors contribute considerably to both clinical affective disorders and subsyndromal mood level. There is moreover evidence to suggest that the genetic basis of bipolar disorder and unipolar depression overlap to some extent, and several linkage analyses have suggested evidence...... for a common susceptibility locus in affective disorders on chromosome 12q24. In this study we investigated the chromosome 12 candidate region for linkage to the mean level of depression symptomatology, over a 10-year follow-up, using a highly informative sample of concordant and discordant twin pairs selected...

  6. Differentially Methylated Genomic Regions in Birth-Weight Discordant Twin Pairs

    DEFF Research Database (Denmark)

    Chen, Mubo; Baumbach, Jan; Vandin, Fabio;

    2016-01-01

    Poor nutrition during critical growth phases may alter the structural and physiologic development of vital organs thus “programming” the susceptibility to adult-onset diseases and disease-related health conditions. Epigenome-wide association studies have been performed in birth-weight discordant...... twin pairs to find evidence for such “programming” effects, but no significant results emerged. We further investigated this issue using a new computational approach: Instead of probing single genomic sites for significant alterations in epigenetic marks, we scan for differentially methylated genomic...

  7. Discordance

    Science.gov (United States)

    Villa, I. M.; Hanchar, J. M.

    2013-12-01

    Half a century ago, discordant U-Pb ages of metamorphic zircon were viewed as Pb loss by diffusion. Various diffusionist schools of thought debated vigorously whether diffusion was episodic or continuous [1], but nobody questioned the reality of diffusive Pb loss. Only imaging by cathodoluminescence (CL) [2] and back-scattered electrons (BSE) [3] brought a paradigm change in U-Pb geochronology. In situ dating shows routinely accretion of young zircon rims onto older cores that never display Pb diffusion gradients across the interface. Other minerals (monazite, xenotime, etc.) show the same pattern: irregular patches of uniform age separated by sharp age gradients coinciding with petrologic boundaries. As U-Pb discordance is caused by diachronous, heterochemical mineral generations, zircon and monazite closure temperatures, and strict diffusionism, are irrelevant [4]. Knowing what to pay attention to, analytical protocols for U-Pb dating include both of the following: (i) CL/BSE characterization of phase mixtures; (ii) mass spectrometric analysis including U/Th ratios (and ideally trace element fingerprinting on the same fraction [5]). It is clear that the petrologic context is just as essential as mass spectrometry for accurate geochronology. The K-Ar community rarely uses imaging, and the tight context between microstructures, mineral chemistry, petrology and geochronology is missed. Yet the data would be clear if one looked for it. CL and/or BSE imaging and X-ray mapping of K-feldspar and micas is finding ubiquitous evidence of discrete patches of juxtaposed mineral generations. The Ca/Cl/K ratios in 39Ar-40Ar dating fulfill the same role as U/Th ratios in U-Pb dating for fingerprinting successive heterochemical mineral generations. Any linear correlation in a common-denominator three-isotope correlation diagram is certain evidence of binary mixing between heterochemical end-members. A correlation in a Ca/K vs Ar/K diagram requires two minerals having different

  8. Xenotropic Murine Leukemia Virus-Related Virus in Monozygotic Twins Discordant for Chronic Fatigue Syndrome

    Science.gov (United States)

    Jerome, Keith R.; Diem, Kurt; Huang, Meei-Li; Selke, Stacy; Corey, Lawrence; Buchwald, Dedra

    2011-01-01

    A recent report suggested an association between xenotropic murine leukemia virus-related virus (XMRV) and chronic fatigue syndrome (CFS). If confirmed, this would suggest that antiretroviral therapy might benefit patients suffering from CFS. We validated a set of assays for XMRV, and evaluated the prevalence of XMRV in a cohort of monozygotic twins discordant for CFS. Stored PBMC were tested with 3 separate PCR assays (one of which was nested) for XMRV DNA, and serum/plasma was tested for XMRV RNA by reverse transcription (RT)-PCR. None of the PBMC samples from the twins with CFS or their unaffected co-twins were positive for XMRV, by any of the assays. One plasma sample, from an unaffected co-twin, was reproducibly positive by RT-PCR. However, serum from the same day was negative, as was a followup plasma sample obtained 2 days after the positive specimen. These data do not support an association of XMRV with CFS. PMID:21795004

  9. Discordant tooth agenesis and peg-shaped in a pair of monozygotic twins: Clinical and molecular study

    Directory of Open Access Journals (Sweden)

    Lívia Azeredo Alves Antunes

    2013-01-01

    Full Text Available The present report aimed to study an uncommon case of a pair of twins that presented a discordant dental phenotype. Family investigation, clinical, radiographic examination and molecular analysis were performed in both girls. Molecular analysis confirmed the monozygosity by deoxyribonucleic acid chip technology. One twin presented tooth agenesis in left upper lateral incisor and peg-shaped on the contra lateral side while the other twin had no dental alterations. The dental casts study employed digital caliper to compare morphological dimensions and showed alteration only in peg-shaped tooth. In conclusion, this study provide support that one or more mutated gene could cause discordances in dental phenotype in these monozygotic twins.

  10. Brain activation during cognitive planning in twins discordant or concordant for obsessive-compulsive symptoms.

    Science.gov (United States)

    den Braber, Anouk; van 't Ent, Dennis; Cath, Danielle C; Wagner, Judith; Boomsma, Dorret I; de Geus, Eco J C

    2010-10-01

    Neuroimaging studies have indicated abnormalities in cortico-striatal-thalamo-cortical circuits in patients with obsessive-compulsive disorder compared with controls. However, there are inconsistencies between studies regarding the exact set of brain structures involved and the direction of anatomical and functional changes. These inconsistencies may reflect the differential impact of environmental and genetic risk factors for obsessive-compulsive disorder on different parts of the brain. To distinguish between functional brain changes underlying environmentally and genetically mediated obsessive-compulsive disorder, we compared task performance and brain activation during a Tower of London planning paradigm in monozygotic twins discordant (n=38) or concordant (n=100) for obsessive-compulsive symptoms. Twins who score high on obsessive-compulsive symptoms can be considered at high risk for obsessive-compulsive disorder. We found that subjects at high risk for obsessive-compulsive disorder did not differ from the low-risk subjects behaviourally, but we obtained evidence that the high-risk subjects differed from the low-risk subjects in the patterns of brain activation accompanying task execution. These regions can be separated into those that were affected by mainly environmental risk (dorsolateral prefrontal cortex and lingual cortex), genetic risk (frontopolar cortex, inferior frontal cortex, globus pallidus and caudate nucleus) and regions affected by both environmental and genetic risk factors (cingulate cortex, premotor cortex and parts of the parietal cortex). Our results suggest that neurobiological changes related to obsessive-compulsive symptoms induced by environmental factors involve primarily the dorsolateral prefrontal cortex, whereas neurobiological changes induced by genetic factors involve orbitofrontal-basal ganglia structures. Regions showing similar changes in high-risk twins from discordant and concordant pairs may be part of compensatory

  11. Global transcript profiles of fat in monozygotic twins discordant for BMI: pathways behind acquired obesity.

    Directory of Open Access Journals (Sweden)

    Kirsi H Pietiläinen

    2008-03-01

    Full Text Available BACKGROUND: The acquired component of complex traits is difficult to dissect in humans. Obesity represents such a trait, in which the metabolic and molecular consequences emerge from complex interactions of genes and environment. With the substantial morbidity associated with obesity, a deeper understanding of the concurrent metabolic changes is of considerable importance. The goal of this study was to investigate this important acquired component and expose obesity-induced changes in biological pathways in an identical genetic background. METHODS AND FINDINGS: We used a special study design of "clonal controls," rare monozygotic twins discordant for obesity identified through a national registry of 2,453 young, healthy twin pairs. A total of 14 pairs were studied (eight male, six female; white, with a mean +/- standard deviation (SD age 25.8 +/- 1.4 y and a body mass index (BMI difference 5.2 +/- 1.8 kg/m(2. Sequence analyses of mitochondrial DNA (mtDNA in subcutaneous fat and peripheral leukocytes revealed no aberrant heteroplasmy between the co-twins. However, mtDNA copy number was reduced by 47% in the obese co-twin's fat. In addition, novel pathway analyses of the adipose tissue transcription profiles exposed significant down-regulation of mitochondrial branched-chain amino acid (BCAA catabolism (p < 0.0001. In line with this finding, serum levels of insulin secretion-enhancing BCAAs were increased in obese male co-twins (9% increase, p = 0.025. Lending clinical relevance to the findings, in both sexes the observed aberrations in mitochondrial amino acid metabolism pathways in fat correlated closely with liver fat accumulation, insulin resistance, and hyperinsulinemia, early aberrations of acquired obesity in these healthy young adults. CONCLUSIONS: Our findings emphasize a substantial role of mitochondrial energy- and amino acid metabolism in obesity and development of insulin resistance.

  12. Failure to Identify Somatic Mutations in Monozygotic Twins Discordant for Schizophrenia by Whole Exome Sequencing

    Institute of Scientific and Technical Information of China (English)

    Nan Lyu; Li-Li Guan; Hong Ma; Xi-Jin Wang; Bao-Ming Wu; Fan-Hong Shang; Dan Wang

    2016-01-01

    Background:Schizophrenia (SCZ) is a severe,debilitating,and complex psychiatric disorder with multiple causative factors.An increasing number of studies have determined that rare variations play an important role in its etiology.A somatic mutation is a rare form of genetic variation that occurs at an early stage of embryonic development and is thought to contribute substantially to the development of SCZ.The aim of the study was to explore the novel pathogenic somatic single nucleotide variations (SNVs) and somatic insertions and deletions (indels) of SCZ.Methods:One Chinese family with a monozygotic (MZ) twin pair discordant for SCZ was included.Whole exome sequencing was performed in the co-twin and their parents.Rigorous filtering processes were conducted to prioritize pathogenic somatic variations,and all identified SNVs and indels were further confirmed by Sanger sequencing.Results:One somatic SNV and two somatic indels were identified after rigorous selection processes.However,none was validated by Sanger sequencing.Conclusions:This study is not alone in the failure to identify pathogenic somatic variations in MZ twins,suggesting that exonic somatic variations are extremely rare.Further efforts are warranted to explore the potential genetic mechanism of SCZ.

  13. Monochorionic-diamniotic discordant growth in a twin pregnancy with one fetus affected by Ebstein's anomaly of tricuspid leaflets.

    Science.gov (United States)

    Fukami, Tatsuya; Goto, Maki; Matsuoka, Sakiko; Sorano, Sumire; Tohyama, Atsushi; Yamamoto, Hiroko; Nakamura, Sumie; Matsuoka, Ryoei; Tsujioka, Hiroshi; Eguchi, Fuyuki

    2016-07-01

    Our patient was diagnosed as having discordant twin growth with Ebstein's anomaly in the larger fetus. Cardiac function was deteriorated in accordance with progression of gestational age. Our observation indicated cardiac failure of the larger fetus. The most important issue in this situation is management of the timing of delivery.

  14. Levels of Adipokines in Amniotic Fluid and Cord Blood Collected from Dichorionic-Diamniotic Twins Discordant for Fetal Growth.

    Directory of Open Access Journals (Sweden)

    Seung Mi Lee

    Full Text Available To compare the concentrations of adipokines in amniotic fluid (AF and cord blood collected from discordant dichorionic-diamniotic (DCDA twin fetuses.The study population included DCDA twins discordant for fetal growth (birth weight difference >10% who either underwent mid-trimester amniocentesis for routine clinical indication (Cohort 1 or whose amniotic fluid was collected at the time of delivery (Cohort 2. In both cohorts, cord blood was collected at delivery.A total of 92 twin pairs were enrolled (n = 49 in Cohort 1; n = 43 in Cohort 2. In Cohort 1, the concentrations of adiponectin (median, 68.5 ng/mL vs 61.4 ng/mL; p<0.05 and leptin (median, 13.9 ng/mL vs 11.2 ng/mL; p<0.1 in mid-trimester AF were significantly higher in smaller compared with larger twins. In Cohort 2, the concentration of serpin E1 (median, 246.0 ng/mL vs 182.8 ng/mL; p<0.01 in AF at delivery was significantly higher in smaller twins, but no difference was noted in adiponectin and leptin concentrations. Levels of adiponectin (median, 10425.5 ng/mL vs 11552.0 ng/mL; p<0.005 and leptin (median, 2.1 ng/mL vs 2.6 ng/mL; p<0.005 were significantly lower in the cord blood of smaller twins whereas cord blood concentrations of serpin E1 (median, 15.5 ng/mL vs 13.3 ng/mL; p<0.05 was higher in the smaller twins.In discordant DCDA twin pairs, concentrations of adiponectin, leptin, and serpin E1 in mid-trimester AF, AF at delivery, and cord blood at birth vary significantly but predictably between the smaller and larger twins.

  15. Dermatoglyphics in relation to brain volumes in twins concordant and discordant for bipolar disorder.

    Science.gov (United States)

    Vonk, R; van der Schot, A C; van Baal, G C M; van Oel, C J; Nolen, W A; Kahn, R S

    2014-12-01

    Palmar and finger dermatoglyphics are formed between the 10th and the 17th weeks of gestation and their morphology can be influenced by genetic or environmental factors, interfering with normal intrauterine development. As both the skin and the brain develop from the same embryonal ectoderm, dermatoglyphic alterations may be informative for early abnormal neurodevelopmental processes in the brain. We investigated whether dermatoglyphic alterations are related to structural brain abnormalities in bipolar disorder and to what extent they are of a genetic and of an environmental origin. Dermatoglyphics and volumetric data from structural MRI were obtained in 53 twin pairs concordant or discordant for bipolar disorder and 51 healthy matched control twin pairs. Structural equation modeling was used. Bipolar disorder was significantly positively associated with palmar a-b ridge count (ABRC), indicating higher ABRC in bipolar patients (rph=.17 (CI .04-.30)). Common genes appear to be involved because the genetic correlation with ABRC was significant (rph-A=.21 (CI .05-.36). Irrespective of disease, ABRC showed a genetically mediated association with brain volume, indicated by a significant genetic correlation rph-A of respectively -.36 (CI -.52 to -.22) for total brain, -.34 (CI -.51 to -.16) total cortical volume, -.27 (CI -.43 to -.08) cortical gray matter and -.23 (CI -.41 to -.04) cortical white matter. In conclusion, a genetically determined abnormal development of the foetal ectoderm between the 10th and 15th week of gestation appears related to smaller brain volumes in (subjects at risk for) bipolar disorder.

  16. Genome-wide blood DNA methylation alterations at regulatory elements and heterochromatic regions in monozygotic twins discordant for obesity and liver fat

    OpenAIRE

    Ollikainen, M; Ismail, K.; Gervin, Kristina; Harris, Jennifer; Lyle, Robert

    2015-01-01

    Background: The current epidemic of obesity and associated diseases calls for swift actions to better understand the mechanisms by which genetics and environmental factors affect metabolic health in humans. Monozygotic (MZ) twin pairs showing discordance for obesity suggest that epigenetic influences represent one such mechanism. We studied genome-wide leukocyte DNA methylation variation in 30 clinically healthy young adult MZ twin pairs discordant for body mass index (BMI; average within-pai...

  17. Monoamniotic twins discordant for anencephaly managed conservatively with good outcomes: two case reports and a review of the literature.

    Science.gov (United States)

    Lim, K I; Dy, C; Pugash, D; Williams, K P

    2005-08-01

    Monoamniotic twin pregnancy discordant for anencephaly (MATDA) is a rare occurrence with only seven prior reported cases. Selective termination has been advocated in managing discordant monoamniotic twins. We report two cases managed expectantly with good outcomes and review other previously reported cases. The first case was a primigravid woman diagnosed with MATDA at 18 weeks. She was managed expectantly until 32 + 5 weeks when a Cesarean section was performed for preterm labor. The surviving female infant weighed 1610 g. The second case was a multigravid woman who was diagnosed with MATDA at 17 + 5 weeks and was managed as an outpatient. An emergency Cesarean section was performed at 31 weeks for non-reassuring monitoring and the surviving male infant weighed 1790 g. In both cases, the survivors were discharged home in good condition. A review of these two cases and those in the literature suggests that expectant management should be considered among management options for this rare condition.

  18. Divergent frequencies of IGF-I receptor-expressing blood lymphocytes in monozygotic twin pairs discordant for Graves' disease: evidence for a phenotypic signature ascribable to nongenetic factors

    DEFF Research Database (Denmark)

    Douglas, Raymond S; Brix, Thomas H; Hwang, Catherine J

    2009-01-01

    Twin Registry, including seven discordant pairs, four pairs concordant for GD, and seven healthy pairs. MAIN OUTCOME MEASURES: Subjects underwent physical examination and laboratory analysis. Surface display of IGF-IR on T and B cells was analyzed by flow cytometry. RESULTS: Twins with GD display...

  19. Progresses of birthweight discordance in monochorionic twins%单绒毛膜双胎出生体质量不一致的研究进展

    Institute of Scientific and Technical Information of China (English)

    李阳

    2013-01-01

    双胎出生体质量(BW)不一致是双胎妊娠特有的并发症,单绒毛膜(MC)双胎BW不一致发生率高于双绒毛膜(DC)双胎,且并发症多、预后较差,因此早期预测并进行相应处理对改善胎儿及新生儿预后具有重要意义.本文就近年来国内外对MC双胎BW不一致的研究进展进行综述.%Birthweight discordance is a characteristic complication of monochorionic twin pregnancies, with higher incidence compared with dichorionic twin pregnancies. How to predict and manage twin pregnancies with birth discordance earlier is crucial to improving the prognosis. The progresses of researching for birthweight discordance of monochorionic twin pregnancies were reviewed in this article.

  20. Gray and white matter volume abnormalities in monozygotic and same-gender dizygotic twins discordant for schizophrenia

    DEFF Research Database (Denmark)

    Hilshoff, Hilleke E.; Brans, Rachel G. H.; van Haren, Neeltje E. M.;

    2004-01-01

    BACKGROUND: Whole brain tissue volume decreases in schizophrenia have been related to both genetic risk factors and disease-related (possibly nongenetic) factors; however, whether genetic and environmental risk factors in the brains of patients with schizophrenia are differentially reflected in g...... matter volume are related to environmental risk factors. Study of genes involved in the (maintenance) of white matter structures may be particularly fruitful in schizophrenia......BACKGROUND: Whole brain tissue volume decreases in schizophrenia have been related to both genetic risk factors and disease-related (possibly nongenetic) factors; however, whether genetic and environmental risk factors in the brains of patients with schizophrenia are differentially reflected...... in gray or white matter volume change is not known. METHODS: Magnetic resonance imaging (1.5 T) brain scans of 11 monozygotic and 11 same-gender dizygotic twin pairs discordant for schizophrenia were acquired and compared with 11 monozygotic and 11 same-gender dizygotic healthy control twin pairs. RESULTS...

  1. Differences in frontal and limbic brain activation in a small sample of monozygotic twin pairs discordant for severe stressful life events

    Directory of Open Access Journals (Sweden)

    Detre A. Godinez

    2016-12-01

    Full Text Available Monozygotic twin pairs provide a valuable opportunity to control for genetic and shared environmental influences while studying the effects of nonshared environmental influences. The question we address with this design is whether monozygotic twins selected for discordance in exposure to severe stressful life events during development (before age 18 demonstrate differences in brain activation during performance of an emotional word-face Stroop task. In this study, functional magnetic resonance imaging was used to assess brain activation in eighteen young adult twins who were discordant in exposure to severe stress such that one twin had two or more severe events compared to their control co-twin who had no severe events. Twins who experienced higher levels of stress during development, compared to their control co-twins with lower stress, exhibited significant clusters of greater activation in the ventrolateral and medial prefrontal cortex, basal ganglia, and limbic regions. The control co-twins showed only the more typical recruitment of frontoparietal regions thought to be important for executive control of attention and maintenance of task goals. Behavioral performance was not significantly different between twins within pairs, suggesting the twins with stress recruited additional neural resources associated with affective processing and updating working memory when performing at the same level. This study provides a powerful glimpse at the potential effects of stress during development while accounting for shared genetic and environmental influences.

  2. Differentially methylated DNA regions in monozygotic twin pairs discordant for rheumatoid arthritis.An epigenome - wide study.

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    Anders Jørgen Svendsen

    2016-11-01

    Full Text Available Objectives: In an explorative epigenome-wide association study (EWAS to search for gene independent, differentially methylated DNA positions (DMPs and regions (DMRs associated with rheumatoid arthritis (RA by studying monozygotic (MZ twin pairs discordant for rheumatoid arthritis.Methods: Genomic DNA was isolated from whole blood samples from 28 monozygotic (MZ twin pairs discordant for RA. DNA methylation was measured using the HumanMethylation450 BeadChips. Smoking, anti-cyclic citrullinated peptide antibodies and immunosuppressive treatment were included as covariates. Pathway analysis was performed using GREAT.Results: Smoking was significantly associated with hypomethylation of a DMR overlapping the promoter region of the RNF5 and the AGPAT1, which are implicated in inflammation and autoimmunity, whereas DMARD treatment induced hypermethylation of the same region. Additionally, the promotor region of both S100A6 and EFCAB4B were hypomethylated and both genes have previously been associated with RA. We replicated several candidate genes identified in a previous EWAS in treatment naïve RA singletons. Gene set analysis indicated the involvement of immunologic signatures and cancer-related pathways in RA.Conclusion: We identified several differentially methylated regions associated with RA which may represent environmental effects or consequences of the disease and plausible biological pathways pertinent to the pathogenesis of rheumatoid arthritis

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

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    Carlo eSelmi

    2014-03-01

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

  4. Gene Expression Profiles from Disease Discordant Twins Suggest Shared Antiviral Pathways and Viral Exposures among Multiple Systemic Autoimmune Diseases.

    Science.gov (United States)

    Gan, Lu; O'Hanlon, Terrance P; Lai, Zhennan; Fannin, Rick; Weller, Melodie L; Rider, Lisa G; Chiorini, John A; Miller, Frederick W

    2015-01-01

    Viral agents are of interest as possible autoimmune triggers due to prior reported associations and widely studied molecular mechanisms of antiviral immune responses in autoimmunity. Here we examined new viral candidates for the initiation and/or promotion of systemic autoimmune diseases (SAID), as well as possible related signaling pathways shared in the pathogenesis of those disorders. RNA isolated from peripheral blood samples from 33 twins discordant for SAID and 33 matched, unrelated healthy controls was analyzed using a custom viral-human gene microarray. Paired comparisons were made among three study groups-probands with SAID, their unaffected twins, and matched, unrelated healthy controls-using statistical and molecular pathway analyses. Probands and unaffected twins differed significantly in the expression of 537 human genes, and 107 of those were associated with viral infections. These 537 differentially expressed human genes participate in overlapping networks of several canonical, biologic pathways relating to antiviral responses and inflammation. Moreover, certain viral genes were expressed at higher levels in probands compared to either unaffected twins or unrelated, healthy controls. Interestingly, viral gene expression levels in unaffected twins appeared intermediate between those of probands and the matched, unrelated healthy controls. Of the viruses with overexpressed viral genes, herpes simplex virus-2 (HSV-2) was the only human viral pathogen identified using four distinct oligonucleotide probes corresponding to three HSV-2 genes associated with different stages of viral infection. Although the effects from immunosuppressive therapy on viral gene expression remain unclear, this exploratory study suggests a new approach to evaluate shared viral agents and antiviral immune responses that may be involved in the development of SAID.

  5. iPSC-Derived Dopamine Neurons Reveal Differences between Monozygotic Twins Discordant for Parkinson’s Disease

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    Chris M. Woodard

    2014-11-01

    Full Text Available Parkinson’s disease (PD has been attributed to a combination of genetic and nongenetic factors. We studied a set of monozygotic twins harboring the heterozygous glucocerebrosidase mutation (GBA N370S but clinically discordant for PD. We applied induced pluripotent stem cell (iPSC technology for PD disease modeling using the twins’ fibroblasts to evaluate and dissect the genetic and nongenetic contributions. Utilizing fluorescence-activated cell sorting, we obtained a homogenous population of “footprint-free” iPSC-derived midbrain dopaminergic (mDA neurons. The mDA neurons from both twins had ∼50% GBA enzymatic activity, ∼3-fold elevated α-synuclein protein levels, and a reduced capacity to synthesize and release dopamine. Interestingly, the affected twin’s neurons showed an even lower dopamine level, increased monoamine oxidase B (MAO-B expression, and impaired intrinsic network activity. Overexpression of wild-type GBA and treatment with MAO-B inhibitors normalized α-synuclein and dopamine levels, suggesting a combination therapy for the affected twin.

  6. Subclinical psychopathology and socio-economic status in unaffected twins discordant for affective disorder

    DEFF Research Database (Denmark)

    Vinberg Christensen, Maj; Kyvik, Kirsten Ohm; Vedel Kessing, Lars

    2006-01-01

    work position and tendency towards being more often unemployed and early retired than the Low-Risk twins. Furthermore, they presented higher rates of subclinical affective symptoms and were more likely to experience a minor psychiatric diagnosis. CONCLUSION: Healthy twins with a high genetic liability...

  7. The Discordant MZ-Twin Method: One Step Closer to the Holy Grail of Causality

    Science.gov (United States)

    Vitaro, Frank; Brendgen, Mara; Arseneault, Louise

    2009-01-01

    Twin studies are well known for their value in quantifying the contribution of genes to population variation in behaviors and personality traits. Twin studies also provide a unique opportunity to untangle the contribution of environmental experiences to emotional and behavioral development. This is particularly true when examining monozygotic (MZ)…

  8. Short and long term perinatal outcome in twin pregnancies affected by weight discordance

    DEFF Research Database (Denmark)

    Vedel, Cathrine; Oldenburg, Anna; Worda, Katharina;

    2017-01-01

    OBJECTIVE: To investigate the association between chorionicity-specific intertwin birthweight (BW) discordance and adverse outcomes including long-term follow-up at 6, 18, and 48-60 months after term via Ages and Stages Questionnaire (ASQ). MATERIAL AND METHODS: In this secondary analysis of a co...

  9. Long-term follow-up and analysis of monozygotic twins concordant for 45,X/46,XY peripheral blood karyotype but discordant for phenotypic sex.

    Science.gov (United States)

    Tho, Sandra P; Jackson, Robert; Kulharya, Anita S; Reindollar, Richard H; Layman, Lawrence C; McDonough, Paul G

    2007-11-01

    We report on the follow-up of a set of monozygotic (MZ) twins who were concordant for peripheral blood karyotype 45,X/46,XY but discordant for phenotypic sex. One twin is a phenotypically normal male and the other twin has asymetrical gonadal dysgenesis. The female twin has the mos45,X/46,XY karyotype in all four tissues: left testis, right streak, vas deferens, and clitoral skin. The normal male twin has the normal 46,XY karyotype in all three tissues tested: foreskin, scrotal skin, and testis. Follow-up of the twins at age 21, revealed persistence of mos45,X/46,XY karyotype in peripheral blood into adult life. However, the male grew up with normal male stature, reaching an adult height of 182 cm. The female twin received low dose estrogen replacement with complete breast development at age 14 years. She reached an adult height of 156 cm. At 21 years of age the male twin had normal testicular endocrine function, but severe oligospermia. The long-term follow-up of this set of MZ twins indicate that the male twin has the mosaicism confined to peripheral blood and has the normal 46,XY male constitution. This was further confirmed by his normal male stature and normal testicular endocrine function. The 45X cell line is likely due to his receiving these cells passively from his twin sister via placental anastomoses in utero. The exposure to these 45,X cells during development may have had an impact on his spermatogenesis.

  10. Genome-wide analysis of DNA methylation differences in muscle and fat from monozygotic twins discordant for type 2 diabetes.

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    Rasmus Ribel-Madsen

    Full Text Available BACKGROUND: Monozygotic twins discordant for type 2 diabetes constitute an ideal model to study environmental contributions to type 2 diabetic traits. We aimed to examine whether global DNA methylation differences exist in major glucose metabolic tissues from these twins. METHODOLOGY/PRINCIPAL FINDINGS: Skeletal muscle (n = 11 pairs and subcutaneous adipose tissue (n = 5 pairs biopsies were collected from 53-80 year-old monozygotic twin pairs discordant for type 2 diabetes. DNA methylation was measured by microarrays at 26,850 cytosine-guanine dinucleotide (CpG sites in the promoters of 14,279 genes. Bisulfite sequencing was applied to validate array data and to quantify methylation of intergenic repetitive DNA sequences. The overall intra-pair variation in DNA methylation was large in repetitive (LINE1, D4Z4 and NBL2 regions compared to gene promoters (standard deviation of intra-pair differences: 10% points vs. 4% points, P<0.001. Increased variation of LINE1 sequence methylation was associated with more phenotypic dissimilarity measured as body mass index (r = 0.77, P = 0.007 and 2-hour plasma glucose (r = 0.66, P = 0.03 whereas the variation in promoter methylation did not associate with phenotypic differences. Validated methylation changes were identified in the promoters of known type 2 diabetes-related genes, including PPARGC1A in muscle (13.9±6.2% vs. 9.0±4.5%, P = 0.03 and HNF4A in adipose tissue (75.2±3.8% vs. 70.5±3.7%, P<0.001 which had increased methylation in type 2 diabetic individuals. A hypothesis-free genome-wide exploration of differential methylation without correction for multiple testing identified 789 and 1,458 CpG sites in skeletal muscle and adipose tissue, respectively. These methylation changes only reached some percentage points, and few sites passed correction for multiple testing. CONCLUSIONS/SIGNIFICANCE: Our study suggests that likely acquired DNA methylation changes in skeletal muscle or adipose tissue gene

  11. Gray and white matter density changes in monozygotic and same-sex dizygotic twins discordant for schizophrenia using voxel-based morphometry

    DEFF Research Database (Denmark)

    Hulshoff Pol, HE; Schnack, HG; Mandl, RC

    2006-01-01

    best reflect the genetic and environmental risk factors in the brains of patients with schizophrenia remains unresolved. 1.5-T MRI brain scans of 11 monozygotic and 11 same-sex dizygotic twin-pairs discordant for schizophrenia were compared to 11 monozygotic and 11 same-sex dizygotic healthy control...... twin-pairs using voxel-based morphometry. Linear regression analysis was done in each voxel for the average and difference in gray and white matter density separately, in each twin-pair, with group (discordant, healthy) and zygosity (monozygotic, dizygotic) as between subject variables, and age, sex...... and handedness as covariates. The t-maps (critical threshold value mid R:tmid R: > 6.0, P

  12. Absence of Substantial Copy Number Differences in a Pair of Monozygotic Twins Discordant for Features of Autism Spectrum Disorder

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    Marina Laplana

    2014-01-01

    Full Text Available Autism spectrum disorder (ASD is a highly heritable disease (~0.9 with a complex genetic etiology. It is initially characterized by altered cognitive ability which commonly includes impaired language and communication skills as well as fundamental deficits in social interaction. Despite the large amount of studies described so far, the high clinical diversity affecting the autism phenotype remains poorly explained. Recent studies suggest that rare genomic variations, in particular copy number variation (CNV, may account for a significant proportion of the genetic basis of ASD. The use of disease-discordant monozygotic twins represents a powerful strategy to identify de novo and inherited CNV in the disorder. Here we present the results of a comparative genome hybridization (CGH analysis with a pair of monozygotic twins affected of ASD with significant differences in their clinical manifestations that specially affect speech language impairment and communication skills. Array CGH was performed in three different tissues: blood, saliva, and hair follicle, in an attempt to identify germinal and somatic CNV regions that may explain these differences. Our results argue against a role of large CNV rearrangements as a molecular etiology of the observed differences. This forwards future research to explore de novo point mutation and epigenomic alterations as potential explanations of the observed clinical differences.

  13. Health-Related Findings Among Twin Pairs Discordant for Leisure-Time Physical Activity for 32 Years: The TWINACTIVE Study Synopsis.

    Science.gov (United States)

    Leskinen, Tuija; Kujala, Urho M

    2015-06-01

    We are lacking very long-term and controlled intervention studies investigating the effects of habitual physical activity on health-related factors. To address this gap, we performed a natural experiment by identifying same-sex twin pairs in which the co-twins of each pair differed with respect to leisure-time physical-activity habits throughout their adult life. Our criterion for the discordance was that the same co-twin had a higher leisure time-activity volume than that of the other member of the pair at the majority -- if not all -- of the follow-up time points according to reported/interviewed physical-activity data. Overall, we identified and conducted multidimensional health-related measurements (including fitness, body composition, cardiometabolic risk factor levels, bone and arterial status, and exercise motivation) of 16 twin pairs (seven monozygotic (MZ) and nine dizygotic (DZ) pairs, mean age 60 years) who had persistent discordance in leisure-time physical-activity habits over three decades (TWINACTIVE study). In our discordant-pair study design, after adjusting for sequence-level genes, both systemic-level metabolic, and site-specific structural findings differed significantly in the pairwise analysis in MZ pairs only. These findings included intrapair differences in accumulated fat depots and structure of heart, arteries, and bones. In addition, our study revealed intrapair differences in metabolic and regulatory pathways, which may partly explain the mechanistic links between long-term physical activity, phenotypic changes, and decreased risk of cardiometabolic diseases.

  14. The impact of laser therapy on fetal growth discordance in twin-to-twin transfusion syndrome O impacto da terapia a laser no crescimento fetal na sindrome de transfusão feto-fetal

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    Renato A. Moreira de Sa

    2005-09-01

    Full Text Available OBJECTIVES: to evaluate the impact of laser therapy on inter-twin discordance in twin-to-twin transfusion syndrome (TTTS. METHODS: biparietal diameter (BPD, head circumference (HC, abdominal circumference (AC, femur length (FL and estimated fetal weight were prospectively collected during a five-year period (1999 to 2004. The inter-twin discordance was expressed as a percentage of the largest twin's measurements. The measurements were made the day before laser, twice following laser and after delivery. The mean values of discordance in measurements and in fetal weight were calculated. ANOVA was used to compare mean values. RESULTS: the mean (SD discordance for BPD, HC, AC, FL and estimated fetal weight the day before laser were 8.53% (5.28, 8.75% (2.76, 16.19% (4.85, 12.92% (5.13 and 28.50% (6.46 respectively. At the at 2nd ultrasound assessment after surgery were 4.37% (3.55, 3.73% (2.71, 8.90% (4.42, 6.61% (4.99 and 19.11% (8.01 respectively; and at birth the weight discordance was 18.55% (8.74. There was a significant decrease in discordance for HC and AC for each ultrasound assessment. CONCLUSIONS: there was a decrease in fetal growth discordance following laser therapy in TTTS. These changes might be related to re-adaptation of blood flow following laser therapy.OBJETIVOS: avaliar impacto da terapia a laser no crescimento fetal na Sindrome de transfusão feto-fetal (STFF. MÉTODOS: diâmetro biparietal (DBP, circunferência cefálica (CC e abdominal (CA, comprimento do fêmur (CF e peso fetal foram colhidos prospectivamente no período de cinco anos (1999 a 2004. A discordância entre os gêmeos foi expressa como porcentagem da medida do maior. As medidas foram feitas um dia antes do laser, duas vezes após e depois do nascimento. A cada exame e pós-parto foram calculadas médias das discordâncias entre medidas e peso fetal. ANOVA foi usada para comparar as médias. RESULTADOS: a discordância média (SD para DBP, CC, CA, CF e peso fetal

  15. Common immune-related exposures/conditions and risk of non-Hodgkin lymphoma: a case-control study of disease-discordant twin pairs.

    Science.gov (United States)

    Wang, Jun; Mack, Thomas M; Hamilton, Ann S; Hwang, Amie E; Nathwani, Bharat N; Masood, Kamil; Buchanan, Laura H; Bernstein, Leslie; Deapen, Dennis M; Martínez-Maza, Otoniel; Cozen, Wendy

    2015-09-01

    We evaluated the association between common immune system-altering experiences and non-Hodgkin lymphoma (NHL) risk using a case-control study of 162 like-sex twin pairs discordant for NHL, identified from the International Twin Study. Information on medical history and evidence of childhood exposure to microbes was obtained by questionnaire from 1998 to 2002. Conditional logistic regression was used to estimate odds ratios and 95% confidence intervals. Intra-twin-pair agreement between twins on individual exposures was high (76%-97%). A negative association between NHL and seasonal hay fever (odds ratio (OR) = 0.28, 95% confidence interval (CI): 0.10, 0.75) and certain allergies (OR = 0.29, 95% CI: 0.13, 0.68) was observed. The number of atopic diseases was negatively associated with NHL (P for trend = 0.0003). A history of infectious mononucleosis was negatively associated with NHL risk (OR = 0.35, 95% CI: 0.14, 0.90). NHL risk was associated with more frequent childhood exposure to microbes during early life (P for trend = 0.04). No differences in association by NHL subtype were observed, although statistical power for these comparisons was low. These observations support the hypothesis that immune-related exposures, especially atopy, are associated with decreased NHL risk. Use of the within-twin-pair study design mitigates confounding by genome, family structure, and unmeasured characteristics of early childhood factors.

  16. Effects of type II collagen epitope carbamylation and citrullination in human leucocyte antigen (HLA)-DR4(+) monozygotic twins discordant for rheumatoid arthritis.

    Science.gov (United States)

    De Santis, M; Ceribelli, A; Cavaciocchi, F; Generali, E; Massarotti, M; Isailovic, N; Crotti, C; Scherer, H U; Montecucco, C; Selmi, C

    2016-09-01

    The aim of this study is to investigate the effect of the native, citrullinated or carbamylated type II human collagen T cell- and B cell-epitopes on the adaptive immune response in rheumatoid arthritis (RA). Peripheral blood T and B cells obtained from a human leucocyte D4-related (antigen DR4(-) HLA-DR4)(+) woman with early RA, her healthy monozygotic twin and an unrelated HLA-DR3(+) woman with early RA were analysed for activation (CD154/CD69), apoptosis (annexin/7-aminoactinomycin), cytokine production [interferon (IFN)γ/interleukin (IL)-17/IL-4/IL-10/IL-6] and functional phenotype (CD45Ra/CCR7) after stimulation with the collagen native T cell epitope (T261-273), the K264 carbamylated T cell epitope (carT261-273), the native B cell epitope (B359-369) or the R360 citrullinated B cell epitope (citB359-369), and the combinations of these. The T cell memory compartment was activated by T cell epitopes in both discordant DR4(+) twins, but not in the DR3(+) RA. The collagen-specific activation of CD4(+) T cells was induced with both the native and carbamylated T cell epitopes only in the RA twin. Both T cell epitopes also induced IL-17 production in the RA twin, but a greater IL-4 and IL-10 response in the healthy twin. The citrullinated B cell epitope, particularly when combined with the carbamylated T cell epitope, induced B cell activation and an increased IL-6/IL-10 ratio in the RA twin compared to a greater IL-10 production in the healthy twin. Our data suggest that circulating collagen-specific T and B cells are found in HLA-DR4(+) subjects, but only RA activated cells express co-stimulatory molecules and produce proinflammatory cytokines. Carbamylation and citrullination further modulate the activation and cytokine polarization of T and B cells.

  17. Pregnancy outcomes of twin pregnancies complicated with growth discordance%双胎妊娠胎儿发育不均衡的妊娠结局

    Institute of Scientific and Technical Information of China (English)

    赫英东; 李雨利; 陈倩

    2014-01-01

    目的 探讨双胎妊娠胎儿发育不均衡的临床特点及预后.方法 回顾性分析2000年1月1日至2012年7月31日在北京大学第一医院产科分娩的576例双胎妊娠孕妇(除外双胎输血综合征病例)资料.根据胎儿腹围以及股骨长估计胎儿体重,分娩后记录新生儿出生体重,根据公式[(较大儿体重-较小儿体重)/较大儿体重×100%]计算双胎体重的差异,体重差异≥25%考虑存在胎儿发育不均衡,<25%为胎儿发育均衡.分析双胎妊娠胎儿发育不均衡的发生率;比较胎儿发育不均衡者(不均衡组,68例)与胎儿发育均衡者(均衡组,508例)的母体并发症(子痫前期、胎膜早破、妊娠期糖尿病、产后出血等)发生率、早产率、围产儿病死率、新生儿出生体重和新生儿合并症(心血管系统疾病和颅内病变)发生率.统计学分析采用t检验或卡方检验. 结果 576例双胎妊娠中,胎儿发育不均衡总体发生率为11.8%(68/576).单绒毛膜双胎胎儿发育不均衡发生率[17.6%(40/227)]高于双绒毛膜双胎[8.0%(28/349)],差异有统计学意义(x2=11.40,P<0.05).胎儿发育不均衡组分娩孕周小于均衡组[(35.6±4.1)周与(36.6±3.2)周,t=1.66,P<0.05],早产率高于均衡组[58.8%(40/68)与47.6% (242/508),x2=3.85,P<0.05].不均衡组围产儿病死率高于均衡组[9.6%(1 3/136)与4.7% (48/1 016),x2=5.84,P<0.05].胎儿发育不均衡者中,单绒毛膜双胎妊娠新生儿颅内病变的发生率明显高于双绒毛膜双胎组[20.9%(14/67)与6.8%(3/44),x2=4.06,P<0.05].结论 双胎妊娠胎儿发育不均衡孕妇较易发生不良妊娠结局.应加强产前保健,并及时评估胎儿的宫内状况,分娩后建议对新生儿进行全面检查并长期随访.%Objective To investigate clinical characteristics and outcomes of twin pregnancies complicated with growth discordance.Methods Five hundred and seventy-six twin pregnancies who delivered between January 1

  18. 双胎胎儿生长不一致妊娠结局的探讨分析%Clinical observation on perinatal outcome in discordant twin pregnancies

    Institute of Scientific and Technical Information of China (English)

    王佳蓉

    2014-01-01

    ObjectiveTo analyze the perinatal outcomes of growth discordant in twins pregnancy. MethodsA retrospective analysis of clinical data was conducted in 24 cases of twin babies who were admitted in our hospital from January 2011 to January 2014, and the 24 cases were divided groups:observation group(14 cases) and control group(10 cases). Twin pairs whose birth weight difference was 20% or more were designated as discordant twins. To compare the difference between of the pairs.ResultsThe perinatal mortality in observation group was significantly higher than that in control group(P0.05). Neonatal occupancy rate in NICU and complication rate were obviously higher in observation group than that in the control group, and there was significant difference(P20%为诊断标准,分为观察组14例和对照组10例(发育一致性),比较两组间孕妇的一般情况。结果观察组并发围生儿死亡率明显高于对照组(P0.05);观察组新生儿入住NICU比率明显高于对照组,两组比较差异有统计学意义(P<0.05)。观察组并发症发生率高于对照组(P<0.05)。结论发育不一致性双胎妊娠并发症及围生儿患病率和死亡率明显高于发育一致性双胎,及早发现和处理双胎发育不一致,是改善胎儿和新生儿预后的关键。

  19. Intrauterine growth characteristics of twins and those twins discordant birthweight%双胎及出生体质量不同一性双胎胎儿宫内生长发育的特点

    Institute of Scientific and Technical Information of China (English)

    韩振艳; 方群; 罗艳敏; 侯红瑛; 陈敏玲; 何志明; 宋花蕾

    2012-01-01

    Objective To investigate the intrauterine growth characteristics of twins and birthweight discordant twins (discordant twins ).Methods Total of 1010 twin pregnancies (2020 fetuses) with complete delivery records from the Department of Obstetrics and Gynecology,the First and Third Affiliated Hospital of SUN Yat-sen University between January 1,2000 and July 31,2010 were studied retrospectively.One handred and ninteen cases (238 fetuses) with intrapair birthweight difference ≥25% were determined as the discordant twins group,and the other 891 cases (1782 fetuses) with intrapair birthweight difference < 25% were identified as the concordant twins group.The singleton control group included 4042 singleton pregnancies in the same period.Results ( 1 ) Comparison of clinical data between the twins groups:the birthweight of larger-twin,smaller-twin and intrapair birthweight difference in the discordant twins group and the concordant twins group were ( 2090± 827 ) g,( 1392 ± 592 ) g,( 33.9 ±9.3 ) %,and ( 2408 ± 543 ) g,( 2191 ± 505 ) g,( 8.9 ± 6.5 ) %,respectively,with significant differences (P<0.01).The incidence of discordant twins was 11.78% (119/1010).Compared with the concordant twins group,the discordant twins group bad higher proportion of monochorionic twins,and higher prevalence of pregnancy complications such as late miscarriage,abnormal umbilical insertion,twin-twin transfusion syndrome and hypertensive disorders in pregnancy ( P < 0.05 ).( 2 ) The characteristics of twin birthweight distribution:① In all the 2020 twins,80.05% (1617/2020) fetuses had birthweight below the 50th percentile of the singleton control group,while 23.71% (479/2020) feeuses got birthweight below the 10th percentile of the singleton control group.② After 19th gestational week,the 50th and 90th percentile of all twins' birthweight were lower than those of singletons.After 38th gestational week,the birthweight of singletons kept increasing and reached its

  20. 产前超声监测羊水量不均衡双胎妊娠的临床价值%Value of prenatal surveillances of ultrasonography in twin pregnancies with amniotic fluid discordance

    Institute of Scientific and Technical Information of China (English)

    刘涛; 吴瑛; 王慧芳; 谭喜平; 甘晗靖; 林琪; 焦阳; 熊奕; 姜燕; 张辉

    2010-01-01

    Objective To evaluate the values of prenatal surveillances of ultrasonography in twin pregnancies with amniotic fluid discordance. Methods Two hundred and seventy cases of diamniotic twins were included. Both postnatal outcomes and prenatal amniotic fluid discordant variations were analyzed,and the incidences of amniotic fluid discordance were compared between the monochorionic-diamniotic(MCDA)and dichorionic-diamniotic (DCDA) gruop. Results Twenty four cases of twins with amniotic fluid discordance were found in the study. The incidence of amniotic fluid discordance in MCDA group was much higher than that in DCDA group (28.9% vs 5.6%, P <0. 001 ) ,and 24 cases of twin-to-twin transfusion syndrome (TTTS) were diagnosed in the former group and none were found in the latter group. Downward tendency of amniotic fluid discordance was shown in non-TTTS cases of MCDA group. Compared with TTTS cases, the postnatal outcomes of non-TTTS cases with amniotic fluid discordance were much better in MCDA group ( P <0.001 ). Conclusions TTTS and MCDA twins with amniotic fluid discordance may overlap each other in the early stage. Serial surveillances of ultrasonography are necessary for prenatal differentiating twin pregnancies complicated by amniotic fluid discordance,and providing strong support to clinical treament.%目的 探讨产前超声监测羊水量不均衡双胎的临床价值.方法 分析270例双羊膜囊双胎中单绒毛膜双羊膜囊双胎(monochorionic-diamniotic twin,MCDA)与双绒毛膜双羊膜囊双胎(dichorionicdiamniotic twin,DCDA)羊水量不均衡的发生率,妊娠过程中羊水量变化趋势及与妊娠结局的关系.结果 共45例双胎间羊水量不均衡,MCDA组37例,其中24例为双胎输血综合征(twin-to-twin transfusion syndrome,TTTS);DCDA组8例,无TTTS发生.MCDA组羊水量不均衡的发生率明显高于DCDA组(P<0.001).MCDA组中羊水量不均衡的非TTTS双胎,羊水量的差异随孕周增加呈减少趋势,且

  1. A Pair of Identical Twins Discordant for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Differ in Physiological Parameters and Gut Microbiome Composition

    Science.gov (United States)

    Giloteaux, Ludovic; Hanson, Maureen R.; Keller, Betsy A.

    2016-01-01

    Patient: Male, 34 Final Diagnosis: ME/CFS Symptoms: Exertion intolerance • loss of functional capacity • pain • severe fatigue Medication: — Clinical Procedure: Cardiopulmonary exercise test Specialty: Sports Medicine Objective: Unknown ethiology Background: Patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) present with profound fatigue, flu-like symptoms, pain, cognitive impairment, orthostatic intolerance, post-exertional malaise (PEM), and exacerbation of some or all of the baseline symptoms. Case Report: We report on a pair of 34-year-old monozygotic twins discordant for ME/CFS, with WELL, the non-affected twin, and ILL, the affected twin. Both twins performed a two-day cardiopulmonary exercise test (CPET), preand post-exercise blood samples were drawn, and both provided stool samples for biochemical and molecular analyses. At peak exertion for both CPETs, ILL presented lower VO2peak and peak workload compared to WELL. WELL demonstrated normal reproducibility of VO2@ventilatory/anaerobic threshold (VAT) during CPET2, whereas ILL experienced an abnormal reduction of 13% in VAT during CPET2. A normal rise in lactate dehydrogenase (LDH), creatine kinase (CK), adrenocorticotropic hormone (ACTH), cortisol, creatinine, and ferritin content was observed following exercise for both WELL and ILL at each CPET. ILL showed higher increases of resistin, soluble CD40 ligand (sCD40L), and soluble Fas ligand (sFasL) after exercise compared to WELL. The gut bacterial microbiome and virome were examined and revealed a lower microbial diversity in ILL compared to WELL, with fewer beneficial bacteria such as Faecalibacterium and Bifidobacterium, and an expansion of bacteriophages belonging to the tailed dsDNA Caudovirales order. Conclusions: Results suggest dysfunctional immune activation in ILL following exercise and that prokaryotic viruses may contribute to mucosal inflammation and bacterial dysbiosis. Therefore, a two-day CPET and molecular

  2. Differential methylation of the X-chromosome is a possible source of discordance for bipolar disorder female monozygotic twins

    NARCIS (Netherlands)

    Rosa, Araceli; Picchioni, Marco M.; Kalidindi, Sridevi; Loat, Caroline S.; Knight, Joanne; Toulopoulou, Timothea; Vonk, Ronald; van der Schot, Astrid C.; Nolen, Willem; Kahn, Rene S.; McGuffin, Peter; Murray, Robin M.; Craig, Ian W.

    2008-01-01

    Monozygotic (MZ) twins may be subject to epigenetic modifications that could result in different patterns of gene expression. Several lines of evidence suggest that epigenetic factors may underlie mental disorders such as bipolar disorder (BD) and schizophrenia (SZ). One important epigenetic modific

  3. X-chromosome inactivation patterns in monozygotic twins and sib pairs discordant for nonsyndromic cleft lip and/or palate

    DEFF Research Database (Denmark)

    Kimani, Jane W; Shi, Min; Daack-Hirsch, Sandra

    2007-01-01

    Nonsyndromic clefts of the lip and/or palate are common birth defects with a strong genetic component. Based on unequal gender ratios for clefting phenotypes, evidence for linkage to the X chromosome and the occurrence of several X-linked clefting syndromes, we investigated the role of skewed X...... of XCI was defined as the deviation in inactivation pattern from a 50:50 ratio. Our analysis revealed no significant difference in the degree of skewing between twin pairs (P = 0.3). However, borderline significant differences were observed in the sister pairs (P = 0.02), with the cleft lip with cleft......, particularly cleft lip and palate....

  4. The Accuracy of Estimating Fetal Weight and Inter-Twin Weight Discordance by Ultrasound in Twin Pregnancies in Women With Increased Body Mass Index.

    Science.gov (United States)

    Al-Obaidly, Sawsan; Parrish, Jacqueline; Murphy, Kellie E; Glanc, Phyllis; Maxwell, Cynthia

    2015-08-01

    Objectifs : Cette étude avait pour objectif de déterminer si la présence d’un IMC maternel prégrossesse accru entraînait une baisse de la précision de l’échographie pour ce qui est de l’estimation du poids fœtal et de la discordance intergémellaire en matière de poids dans le cadre de grossesses gémellaires, par comparaison avec des femmes présentant un IMC normal. Méthodes : Nous avons mené une étude de cohorte rétrospective portant sur des femmes qui présentaient un IMC prégrossesse (ou aux débuts de la grossesse) connu, qui ont accouché après 28 semaines de gestation à la suite d’une grossesse gémellaire viable entre 2008 et 2011, et qui ont subi un examen échographique visant l’estimation du poids fœtal dans les deux semaines ayant précédé l’accouchement. Le poids fœtal estimé (PFE) par échographie a été comparé au poids réel de chacun des jumeaux, puis la discordance intergémellaire en matière de poids (définie comme une différence de poids entre les jumeaux de plus de 25 %) a été stratifiée en fonction de l’IMC de la patiente. Nous avons cherché à déterminer si le PFE et la discordance intergémellaire en matière de poids avaient été affectés lorsque l’accouchement était survenu de 8 à 14 jours à la suite de l’échographie, par comparaison avec un accouchement étant survenu dans les sept jours de la tenue de l’échographie. Résultats : Nous avons pu identifier, au total, 300 grossesses gémellaires pour lesquelles l’IMC maternel prégrossesse était connu : 179 femmes présentaient une insuffisance pondérale ou un poids normal (IMC grossesse gémellaire, l’estimation du poids fœtal par échographie semble être plus fiable lorsqu’elle est menée peu avant l’accouchement.

  5. Gene expression profiling of lymphoblastoid cell lines from monozygotic twins discordant in severity of autism reveals differential regulation of neurologically relevant genes

    Directory of Open Access Journals (Sweden)

    Lee Norman H

    2006-05-01

    Full Text Available Abstract Background The autism spectrum encompasses a set of complex multigenic developmental disorders that severely impact the development of language, non-verbal communication, and social skills, and are associated with odd, stereotyped, repetitive behavior and restricted interests. To date, diagnosis of these neurologically based disorders relies predominantly upon behavioral observations often prompted by delayed speech or aberrant behavior, and there are no known genes that can serve as definitive biomarkers for the disorders. Results Here we demonstrate, for the first time, that lymphoblastoid cell lines from monozygotic twins discordant with respect to severity of autism and/or language impairment exhibit differential gene expression patterns on DNA microarrays. Furthermore, we show that genes important to the development, structure, and/or function of the nervous system are among the most differentially expressed genes, and that many of these genes map closely in silico to chromosomal regions containing previously reported autism candidate genes or quantitative trait loci. Conclusion Our results provide evidence that novel candidate genes for autism may be differentially expressed in lymphoid cell lines from individuals with autism spectrum disorders. This finding further suggests the possibility of developing a molecular screen for autism based on expressed biomarkers in peripheral blood lymphocytes, an easily accessible tissue. In addition, gene networks are identified that may play a role in the pathophysiology of autism.

  6. Gêmeas idênticas discordantes para a doença de Cushing: relato de caso Identical twins discordant for Cushing's disease: case report

    Directory of Open Access Journals (Sweden)

    MARCELO MAIA PINHEIRO

    1999-09-01

    Full Text Available A doença de Cushing é rara em crianças e sua ocorrência em gêmeos é ainda mais rara. O presente estudo relata a ocorrência de gêmeas idênticas discordantes quanto à doença de Cushing. Uma das gêmeas, desenvolveu síndrome de Cushing aos 10 anos de idade. Sua investigação demonstrou cortisol urinário elevado, ACTH sérico elevado e testes de supressão com dexametasona compatíveis com doença de Cushing. A RMN mostrou macroadenoma hipofisário que foi operado por via transesfenoidal. O estudo imuno-histoquímico confirmou a presença de células produtoras de ACTH. A paciente entrou em remissão clínica e laboratorial desde a cirurgia. Após o desaparecimento dos estigmas do Cushing, a paciente reiniciou ganho estatural, mas permanece menor que sua irmã gêmea. Esta última permanece saudável 4 anos após o início da doença de sua irmã. Este é o terceiro caso do gênero relatado na literatura. Estes achados sugerem que fatores não genéticos estão envolvidos na gênese da doença de Cushing.Cushing's disease is rare in children and its ocurrence in identical twins is extremely rare. This paper reports on identical twins discordant for Cushing's disease. One of them first presented with a cushingoid phenotype by the age of 10. Her evaluation showed an increased urinary free-cortisol and serum ACTH. Her pattern in the dexametazone supression tests was compatible with Cushing's disease. MRI disclosed a pituitary macroadenoma which was removed by the transesphenoidal approach. Immunohistochemical studies of the tumor showed the presence of ACTH-producing cells. The patient went into clinical and laboratorial remission after surgery. She re-started to grow after the disappearance of the Cushing's phenotype but she is still shorter than her healthy sister. The latter remains disease-free 4 years after her sister's diagnosis. This represents the third such case reported in the literature. Our findings suggest that acquired

  7. 双胎妊娠生长不一致对新生儿甲状腺功能的影响%Effects of growth-discordant twin pregnancies on thyroid function of neonates

    Institute of Scientific and Technical Information of China (English)

    陈怡博; 余颀; 陈志央; 庄丹燕; 潘婕文; 王飞; 卢文波

    2016-01-01

    性甲低的概率较大.%Objective To investigate the effects of growth-discordant twin pregnancies on neonatal thyroid stimulating hormone (TSH) level and congenital hypothyroidism (CH).Methods A total of 3 444 live-birth twin neonates born between January 1,2012 and December 30,2014 in Ningbo City were enrolled.Blood samples via heel puncture were collected and tested.Incidence of CH in singleton and twin neonates was compared.Deviation of birth weight larger than 25% in twin neonates was set as the criteria for discordant growth.TSH and 17 α-hydroxylase levels in CH twins and normal twins,with or without discordant growth,were compared.Chi-square and non-parametric statistics were performed for data analysis.Results The incidence of CH in twin neonates was 0.56% (19/3 444),higher than that in singleton neonates [0.09% (203/225 712),x2=76.225,P<0.01].Among nineteen CH twins,CH occurred in both twins in eight cases (four twins) and in one of the twins in eleven cases.The gestational age at birth in the eight CH twins were less than 37 weeks,with four males and four females;five were low birth weight infants;one twin were dichorionic,and three twins were monochorionic.In the eleven cases of CH occurring in one of the twins,the gestational age was less than 37 weeks in nine cases,eight were low birth weight infants,six were male and five female;seven were monochorionic and four were dichoronic twins.Five cases of temporary hypothyroidism were all low birth weight infants among the growth-discordant twins.CH cases in growth-discordant group had lower birth weight than their normal twins [M(P25-P75),2 100 (1 800-2 600) vs 2 770 (2 530-2 960) g,Z=4.369],and a higher TSH level [15.4 (11.8-18.5) vs 6.4 (4.8-7.9) mU/L,Z=6.339] (both P<0.05).In normal twins with or without discordant growth,the neonates with a lower birth weight had a higher TSH level [3.6(2.5-4.7) vs 2.4(1.8-2.9) mU/L,Z=0.962] in weight consistent group,compared with 6.0(4.4-7.8) vs 3.4(1.9-4.1) mU/L in weight inconsistent group

  8. Clinical Analysis and Literature Review in 26 Cases of Discordant Growth Twin%双胎妊娠生长不一致26例临床分析及文献复习

    Institute of Scientific and Technical Information of China (English)

    杨正勤

    2014-01-01

    目的:分析双胎妊娠生长不一致的孕产妇及围产儿情况。方法:收集我院产科2009年8月-2013年8月住院分娩的26例双胎妊娠生长不一致孕产妇的临床资料,并随机选取26例同期住院分娩的双胎妊娠生长一致孕产妇作为对照组,分析比较两组间孕产妇孕期情况及围产儿结局。结果:研究组孕产妇一般情况与对照组无明显差异(P>0.05);研究组孕产妇合并妊娠期高血压疾病、双胎输血综合征、一胎胎死宫内、胎儿畸形的发生率高于对照组。研究组小于孕龄儿、新生儿窒息、转NICU、围产儿死亡的发生率明显高于对照组,差异有统计学意义(P<0.05)。结论:双胎妊娠生长不一致的母体并发症及围产儿预后较差。早发现、早诊断、及时干预及治疗对改善胎儿及新生儿预后具有重要意义。%Objective :To analyze the maternal and perinatal outcomes of discordant growth twin .Methods:The clinical data of 26 pregnant and lying-in women with discordant growth twin hospitalized in our hospital from August 2009 to August 2013 were collected ,and randomly selected 26 pregnant women with consistent grow th twin in our hospital from the same period of time were chosen as control group .Maternal prenatal and perinatal outcomes were compared between these two groups .Results:There was no significant difference in the two groups in the general situation of pregnant and lying-in women(P> 0 .05) .The incidence of hypertensive disorder complicating pregnancy ,twin-twin transfusion syndrome ,single intrauterine fetal demise and fetal abnormalities of research group were significantly higher than control group .Small for gestational age ,asphyxia neonatorum ,neonatal occupancy in NICU and perinatal mortality were obviously higher in study group than that in the control group (P<0 .05) .Conclusion :Maternal complications and perinatal outcomes fo discordant growth twin were poor

  9. 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.

  10. Monozygotic twin pairs discordant for Hashimoto's thyroiditis share a high proportion of thyroid peroxidase autoantibodies to the immunodominant region A. Further evidence for genetic transmission of epitopic "fingerprints"

    DEFF Research Database (Denmark)

    Brix, Thomas Heiberg; Hegedüs, Laszlo; Gardas, Andrzej;

    2011-01-01

    Thyroid peroxidase antibodies (TPOAbs) in patients with Hashimoto's thyroiditis (HT) predominantly react with two immunodominant regions (IDR-A, IDR-B). Theoretically, as shown for the level of TPOAbs, the autoantibody epitopic recognition of the IDRs could be under genetic control. To examine this......, we compared the distribution of TPOAb epitopic fingerprints between healthy monozygotic (MZ) co-twins and siblings to patients with clinically overt HT with a control group of euthyroid subjects, matched for sex and age, but without autoimmune thyroid disease (AITD) among their first-degree relatives...

  11. Energy expenditure, body composition and insulin response to glucose in male twins discordant for the Trp64Arg polymorphism of the beta3-adrenergic receptor gene

    DEFF Research Database (Denmark)

    Højlund, K; Christiansen, C; Bjørnsbo, K S;

    2006-01-01

    and environmental background, the Trp64Arg polymorphism of the beta3AR gene is associated with lower fat mass, fasting insulin levels and an appropriate insulin response to glucose. Thus, heterozygosity for the Trp64Arg variant is unlikely to increase the risk of obesity, insulin resistance or type 2 diabetes.......AIM: The tryptophan to arginine change in position 64 (Trp64Arg) polymorphism of the beta3-adrenergic receptor (beta3AR) gene has been associated with an increased prevalence of obesity, insulin resistance and type 2 diabetes. In this, decreased rates of energy expenditure and impaired insulin......-ray absorptiometry scanning and energy expenditure by indirect and direct calorimetry. RESULTS: Twins heterozygous for the Trp64Arg polymorphism showed significantly lower fat mass independent of the method used, and significantly lower fasting insulin and glucose concentrations compared with their homozygous wild...

  12. Monogamy of Quantum Discord

    CERN Document Server

    Ren, Xi-Jun

    2011-01-01

    Quantum discord is not monogamous. We consider a pure tripartite state and show that the monogamy inequality of quantum discord is related with a relation between quantum mutual information and entanglement of formation of two parties. The upper bounds of quantum discord and classical correlation are presented. Our results relate the correlations present in a bipartite system with the monogamy or polygamy property of quantum discord in a tripartite pure state. The relation, which is about three important concepts in quantum information theory, quantum discord, entanglement of formation and mutual information, may provide new insights for their further understanding.

  13. Socioeconomic position and twins' health

    DEFF Research Database (Denmark)

    Osler, Merete; McGue, Matt; Christensen, Kaare

    2007-01-01

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

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

    OpenAIRE

    Jena A; Duggal R; Mathur V; Parkash H

    2005-01-01

    Etiology of class-III malocclusion is generally believed to be genetic. A wide range of environmental factors have been suggested as contributing factors for the development of class-III malocclusion. Twin study is one of the most effective methods available for investigating genetically determined variables of malocclusion. Discordancy for class-III malocclusion is a frequent finding in dizygotic twins. However, class-III malocclusion discordancy in monozygotic twins is a rare finding. The p...

  15. Epigenetic Epidemiology of Complex Diseases Using Twins

    DEFF Research Database (Denmark)

    Tan, Qihua

    2013-01-01

    In the past decades, studies on twins have had a great impact on dissecting the genetic and environmental contributions to human diseases and complex traits. In the era of functional genomics, the valuable samples of twins help to bridge the gap between gene activity and environmental conditions...... through multiple epigenetic mechanisms. This paper reviews the new developments in using twins to study disease-related epigenetic alterations, links them to lifetime environmental exposure with a focus on the discordant twin design and proposes novel data-analytical approaches with the aim of promoting...... a more efficient use of twins in epigenetic studies of complex human diseases....

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

    Directory of Open Access Journals (Sweden)

    Jena A

    2005-03-01

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

  17. Twin methodology in epigenetic studies

    DEFF Research Database (Denmark)

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

    2015-01-01

    of diseases to molecular phenotypes in functional genomics especially in epigenetics, a thriving field of research that concerns the environmental regulation of gene expression through DNA methylation, histone modification, microRNA and long non-coding RNA expression, etc. The application of the twin method...... to molecular phenotypes offers new opportunities to study the genetic (nature) and environmental (nurture) contributions to epigenetic regulation of gene activity during developmental, ageing and disease processes. Besides the classical twin model, the case co-twin design using identical twins discordant...... for a trait or disease is becoming a popular and powerful design for epigenome-wide association study in linking environmental exposure to differential epigenetic regulation and to disease status while controlling for individual genetic make-up. It can be expected that novel uses of twin methods in epigenetic...

  18. Optimality of Gaussian discord.

    Science.gov (United States)

    Pirandola, Stefano; Spedalieri, Gaetana; Braunstein, Samuel L; Cerf, Nicolas J; Lloyd, Seth

    2014-10-03

    In this Letter we exploit the recently solved conjecture on the bosonic minimum output entropy to show the optimality of Gaussian discord, so that the computation of quantum discord for bipartite Gaussian states can be restricted to local Gaussian measurements. We prove such optimality for a large family of Gaussian states, including all two-mode squeezed thermal states, which are the most typical Gaussian states realized in experiments. Our family also includes other types of Gaussian states and spans their entire set in a suitable limit where they become Choi matrices of Gaussian channels. As a result, we completely characterize the quantum correlations possessed by some of the most important bosonic states in quantum optics and quantum information.

  19. Monozygotic twin pairs discordant for Hashimoto's thyroiditis share a high proportion of thyroid peroxidase autoantibodies to the immunodominant region A. Further evidence for genetic transmission of epitopic “fingerprints”

    DEFF Research Database (Denmark)

    Brix, Thomas Heiberg; Hegedüs, Laszlo; Gardas, Andrzej;

    2010-01-01

    Thyroid peroxidase antibodies (TPOAbs) in patients with Hashimoto's thyroiditis (HT) predominantly react with two immunodominant regions (IDR-A, IDR-B). Theoretically, as shown for the level of TPOAbs, the autoantibody epitopic recognition of the IDRs could be under genetic control. To examine this......, we compared the distribution of TPOAb epitopic fingerprints between healthy monozygotic (MZ) co-twins and siblings to patients with clinically overt HT with a control group of euthyroid subjects, matched for sex and age, but without autoimmune thyroid disease (AITD) among their first-degree relatives...

  20. The effect of intrauterine growth on mental and psychomoter development in one-year-old discordant twins infants%宫内发育不一致性双胎出生后1年婴儿生长发育的研究

    Institute of Scientific and Technical Information of China (English)

    项慧秋; 黄贤苹; 金佳希; 邵浩然; 池美珠; 林峰; 许张晔

    2016-01-01

    目的:研究宫内发育不一致性双胎出生后1年左右婴儿的生长发育,评估发育不一致性双胎远期婴儿的生长发育情况。方法:2012年1月至2013年12月在温州医科大学附属第一医院和附属第二医院出生的宫内发育不一致性双胎34对,出生后1年左右进行体格检查和精神运动发育测定,以出生时的体质量差异分为低出生体质量组和高出生体质量组。结果:低出生体质量组1岁婴儿身高、体质量及头围均低于高出生体质量组,差异有统计学意义(P<0.05)。低出生体质量组的1岁婴儿精神发育指数(MDI)和运动发育指数(PDI)均低于高出生体质量组,2组比较,PDI差异有统计学意义(P<0.05),而MDI差异无统计学意义(P>0.05)。低出生体质量组6名(占17.6%)1岁婴儿运动发育迟缓(PDI<70),明显高于高出生体质量组(1名,占2.9%)运动发育迟缓的发生率(P<0.05)。多元线性回归分析显示身高、体质量对PDI的影响有显著的统计学意义(F=11.40,P=0.0012;F=6.21,P=0.0153)。结论:发育不一致性双胎出生后的体质量差异将持续性影响至出生后1年婴儿的身高、体质量和头围的体格发育以及运动发育。%Objective: To assess the effect of intrauterine growth on mental and psychomoter development in one-year-old discordant twins infants.Methods: Total of 34 discordant twin pregnancies (68 one-year-old dis-cordant twins infants) with complete delivery records in Obstetrics department of the First and Second Afifliated Hospital of Wenzhou Medical University from January 2012 to December 2013 were followed-up. According to the discordant birthweight, each pair infant was divided into small weight group and large weight group. Weight, length, head circumferences, the mental developmental index (MDI) and psychomotor developmental index (PDI) were measured.Results: Small weight group was lower

  1. Danish cohort of monozygotic inflammatory bowel disease twins

    DEFF Research Database (Denmark)

    Moller, Frederik Trier; Knudsen, Lina; Harbord, Marcus

    2016-01-01

    comprised 31 UC, 5 IBDU (IBD unclassified), and 8 CD discordant pairs. In the co-twins not affected by IBD, calprotectin was above 100 μg/g in 2 participants, and above 50 μg/g in a further 5 participants. CONCLUSION: The presented IBD twin cohorts are an excellent resource for bioinformatics studies...

  2. Motor Disorder and Anxious and Depressive Symptomatology: A Monozygotic Co-Twin Control Approach

    Science.gov (United States)

    Pearsall-Jones, Jillian G.; Piek, Jan P.; Rigoli, Daniela; Martin, Neilson C.; Levy, Florence

    2011-01-01

    The aim of this study was to investigate the relationship between poor motor ability and anxious and depressive symptomatology in child and adolescent monozygotic twins. The co-twin control design was used to explore these mental health issues in MZ twins concordant and discordant for a motor disorder, and controls. This methodology offers the…

  3. There Is a World outside of Experimental Designs: Using Twins to Investigate Causation

    Science.gov (United States)

    Hart, Sara A.; Taylor, Jeanette; Schatschneider, Christopher

    2013-01-01

    This study introduces a co-twin control method commonly used in the medical literature but not often within educational research. This method allows for a comparison of twins discordant for an "exposure," approximating alternative outcomes in the counterfactual model. Example analyses use data drawn from the Florida Twin Project on…

  4. Twin-twin transfusion syndrome - diagnosis and prognosis

    Directory of Open Access Journals (Sweden)

    Hajrić-Egić Amira

    2003-01-01

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

  5. ACARDIAC TWIN

    OpenAIRE

    Vinayachandran; Jyothi,; Bindu; Umadevi

    2014-01-01

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

  6. Twin methodology in epigenetic studies.

    Science.gov (United States)

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

    2015-01-01

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

  7. Quantum Games and Quantum Discord

    CERN Document Server

    Nawaz, Ahmad

    2010-01-01

    We quantize prisoners dilemma and chicken game by our generalized quantization scheme to explore the role of quantum discord in quantum games. In order to establish this connection we use Werner-like state as an initial state of the game. In this quantization scheme measurement can be performed in entangled as well as in product basis. For the measurement in entangled basis the dilemma in both the games can be resolved by separable states with non-zero quantum discord. Similarly for product basis measurement the payoffs are quantum mechanical only for nonzero values of quantum discord.

  8. Operational interpretations of quantum discord

    CERN Document Server

    Cavalcanti, D; Boixo, S; Modi, K; Piani, M; Winter, A

    2010-01-01

    Quantum discord is a quantifier of non-classical correlations that goes beyond the standard classification of quantum states into entangled and unentangled ones. Although it has received considerable attention, it still lacks any precise interpretation in terms of some protocol in which quantum features are relevant. Here we give quantum discord its first operational meaning in terms on consumption of entanglement in an extended quantum state merging protocol. We go on to show that the asymmetry of quantum discord is related to the performance imbalance in quantum state merging and dense coding.

  9. Methylation matters? Decreased methylation status of genomic DNA in the blood of schizophrenic twins.

    Science.gov (United States)

    Bönsch, Dominikus; Wunschel, Michael; Lenz, Bernd; Janssen, Gesa; Weisbrod, Matthias; Sauer, Heinrich

    2012-08-15

    Studies of schizophrenia inheritance in identical twins show a concordance of about 50%, which supports an epigenetic model. In our present study we investigated methylation of genomic DNA and promoter methylation of Reelin and SOX10 genes in peripheral blood of twins suffering from schizophrenia. Global DNA methylation was reduced (52.3%) in schizophrenic twins if compared with healthy control twins (65.7%). The reduced methylation was significant in males only. We also found a similar hypomethylation in the non-affected twins of discordant pairs and a mixed group of psychiatric controls. In discordant twins there was a relative hypermethylation of the SOX10 promoter. Within-pair-difference of methylation of Reelin promoter was significantly lower in monozygotic twins than in dizygotic twins.

  10. Profile of asymmetrical retinopathy of prematurity in twins

    Directory of Open Access Journals (Sweden)

    Azad Rajvardhan

    2010-01-01

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

  11. Causal direction between respiratory syncytial virus bronchiolitis and asthma studied in monozygotic twins

    DEFF Research Database (Denmark)

    Poorisrisak, Porntiva; Halkjaer, Liselotte Brydensholt; Thomsen, Simon Francis;

    2010-01-01

    Respiratory syncytial virus (RSV) bronchiolitis has been associated with later development of asthma, wheezing, abnormal pulmonary function, and sensitization. Our aim was to determine the differential effect within monozygotic (MZ) twin pairs discordant for severe RSV bronchiolitis in infancy...

  12. Twin anemia polycythemia sequence: a single center experience and literature review.

    Science.gov (United States)

    Moaddab, Amirhossein; Nassr, Ahmed A; Espinoza, Jimmy; Ruano, Rodrigo; Bateni, Zhoobin H; Shamshirsaz, Amir A; Mandy, George T; Welty, Stephen E; Erfani, Hadi; Popek, Edwina J; Belfort, Michael A; Shamshirsaz, Alireza A

    2016-10-01

    Twin anemia polycythemia sequence (TAPS) is defined by significant intertwin hemoglobin discordance without the amniotic fluid discordance that characterizes twin-twin-transfusion syndrome (TTTS) in monochorionic twin pregnancies. TAPS is an uncommon condition which can either occur spontaneously, or following fetoscopic laser ablation for TTTS. This complication is thought to result from chronic transfusion through very small placental anastomoses; however, the pathogenesis of TAPS remains unknown. Consequently, there is no consensus in the management of TAPS. In this article, three cases of TAPS are described and we review the literature on this uncommon pregnancy complication.

  13. Lessons from BWS twins: Complex maternal and paternal hypomethylation and a common source of haematopoietic stem cells

    NARCIS (Netherlands)

    J. Bliek (Jet); M. Alders (Mariëlle); S.M. Maas (Saskia); R.J. Oostra; D.M. Mackay (Deborah); K. van der Lip (Karin); J.L. Callaway (Johnatan); A.S. Brooks (Alice); S. van't Padje (Sandra); A. Westerveld (Andries); N.J. Leschot (Nico); M.M.A.M. Mannens (Marcel)

    2009-01-01

    textabstractThe Beckwith-Wiedemann syndrome (BWS) is a growth disorder for which an increased frequency of monozygotic (MZ) twinning has been reported. With few exceptions, these twins are discordant for BWS and for females. Here, we describe the molecular and phenotypic analysis of 12 BWS twins and

  14. Monochorionic twins with the same blood karyotype of 46,XY/47,XYY but different phenotypes.

    Science.gov (United States)

    Wuttikonsammakit, Piyawadee; Tanawattanacharoen, Somchai; Uerpairojkit, Boonchai

    2010-02-01

    We report the case of a 13-year-old woman who was pregnant with phenotypically discordant monochorionic twins: one with cystic hygroma and hydrops, the other one normal. Fetal blood sampling was performed by intrahepatic blood collection for karyotyping of both fetuses, revealing the same genotype of 46,XY/47,XYY in 2:1 proportion. Phenotypic discordance in monozygotic twins can have various causes, such as placental vascular anatomy, differences in allocation of the number of blastomeres or genetic postzygotic events.

  15. Twin births

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  16. Metabolismo de glicose em gêmeos monozigóticos discordantes para aptidão cardiorrespiratória Metabolismo de glucosa en gemelos monocigóticos discordantes para aptitud cardiorrespiratoria Glucose metabolism in discordant monozygotic twins for cardiorespiratory fitness

    Directory of Open Access Journals (Sweden)

    Marcos Roberto Queiroga

    2013-03-01

    L.kg-1.min-1 y fueron divididos en dos grupos, de alta y baja aptitud. Los grupos fueron comparados a partir de la prueba pareada de Wilcoxon, teniendo en vista la asimetría de los datos. RESULTADOS: En promedio, los gemelos del grupo de alta aptitud presentaron consumo máximo de oxígeno el 17% superior (13,5±3,7mL.kg-1.min-1 a sus hermanos menos aptos. No hubo diferencia entre los grupos para las concentraciones de insulina (36,5±34,6 versus 25,3±13,7mg/dL; pOBJECTIVE: To determine if glucose and insulin concentrations are regulated by cardiorespiratory fitness (VO2max regardless of their genetic effects. METHODS: This cross-sectional study enrolled 38 pairs of young monozygotic twins (11 to 18 years-old. All subjects underwent a progressive maximal exercise test on a treadmill to determine the VO2max with gas exchange analysis (MedGraphics VO2000® - Medical Graphics Corp., St. Paul, MN. Blood samples were drawn after fasting to determine glucose and insulin levels. Monozygosity was confirmed by genotyping 15 informative genetic markers. Nine pairs had at least 10mL.kg-1.min-1 difference in VO2max and were divided into the more and less active group, according to their VO2max. Mean differences between more and less active groups were evaluated by Wilcoxon's test for paired data. RESULTS: On average, twins from the more active group presented a 17% (13.5±3.7mL.kg-1.min-1 higher VO2max compared to their less active siblings. No significant differences were observed between the groups for fasting insulin (36.5±34.6 versus 25.3±13.7mg/dL; p<0.813. However, the more active twins had lower fasting glucose than the less active ones (82.9±7.3 versus 86.7±7.6mg/dL; p<0.010. CONCLUSIONS: In this case-control study (discordant monozygotic twins, the less active co-twins were characterized by higher fasting plasma glucose levels. This implies that poor cardiorespiratory fitness can be associated with defective glucose metabolism regardless of genetic factors.

  17. 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

    OBJECTIVE: To disentangle the influences on health of selection processes related to genetic and rearing environmental factors from factors related to marriage benefits. We compared health status among same-sex male and female twin pairs who lived together during childhood and were discordant...... or concordant on adult marital status. METHODS: A cross-sectional survey of a random sample of middle-aged Danish twins was conducted in 1998 to 1999. This study included 1175 same-sex twin pairs (52.5% monozygotic (MZ) and 47.5% dizygotic (DZ)). Data were obtained on adult marital status and on height, body...

  18. Birth weight discordance and perinatal mortality among triplets

    Directory of Open Access Journals (Sweden)

    Egić Amira

    2005-01-01

    Full Text Available INTRODUCTION. The incidence of multiple births has increased in the last decade. Perinatal mortality in triplets is significantly greater than in twin and singleton births. OBJECTIVE. The objective of this study was to describe the extent of birth weight discordance among triplets and to identify its association with an increased risk of perinatal mortality. METHOD A retrospective analysis of triplet births, for the period 1993-2003, was conducted at the Gynaecological-Obstetric Clinic "Narodni Front" in Belgrade. Birth weight discordance was defined as the difference in birth weight between the largest and the smallest triplet's weight of more than 20%. RESULTS. The rate of triplets has increased by almost 75% between the first (7.7% and the last (29.6% 5-year period of the last decade. Triplets are becoming more common because of the frequent use of assisted reproductive technology as a treatment for infertility. In the period 1993-2003, there were a total of 40 triplet live births (24 weeks and greater with incidence of 0.06%. There was no clear association between maternal age, parity, method of conception, birth gestational age, and disorders complicating pregnancy with birth discordance more than 20%. Regarding birth weight groups, statistical significance occurred only in the <999 grams group for discordant and in the 2000-2499 grams group for concordant triplets. Overall, the perinatal mortality rate in the group was 10.8%, the foetal mortality rate was 1.7% (2/120, and the neonatal (0-28 days mortality rate was 9.1% (11/120. An odds ratio of 95% confidence interval shows 3 times greater risk for adverse perinatal outcome in the discordant group. However, the difference was not significant. CONCLUSION. Increasing birth weight discordance may increase the risk of adverse perinatal outcome. Triplet pregnancies, being high risk, require intensive antenatal care in order to prevent preterm delivery and ultrasound in order to diagnose foetal

  19. How Do Friends Influence Smoking Uptake? Findings from Qualitative Interviews with Identical Twins

    Science.gov (United States)

    McLeod, Kim; White, Victoria; Mullins, Robyn; Davey, Claire; Wakefield, Melanie; Hill, David

    2008-01-01

    The smoking behavior of friends is a major risk factor for adolescent smoking uptake. To explore the social context of smoking experimentation and consolidation with a particular focus on friends, the authors interviewed both members of 14 young adult identical twin pairs who were discordant for smoking. The different smoking status of twins was…

  20. Risk factors for asthma in young adults: a co-twin control study

    DEFF Research Database (Denmark)

    Thomsen, S F; Ulrik, C S; Kyvik, K O;

    2006-01-01

    BACKGROUND: The liability to asthma is influenced both by genetic and environmental factors. The objective of this study was to identify risk factors for asthma in young adult twin pairs during an 8-year period. METHODS: From the birth cohorts 1953-1982 of the Danish Twin Registry, 6,090 twin pairs...... who were initially unaffected with respect to asthma at a nationwide questionnaire-based study in 1994 participated in a similar follow-up study in 2002. Subjects were regarded incident asthma cases when responding affirmatively to the question 'Do you have, or have you ever had asthma'? in 2002....... Pairs in which only one twin developed asthma -- discordant pairs -- were identified and conditional logistic regression was applied to detect effects of risk factors. RESULTS: A total of 126 monozygotic (MZ) and 273 dizygotic (DZ) discordant twin pairs were identified. In MZ twins hay fever (OR = 3...

  1. Twins with omphalocele in Denmark (1970-1989)

    DEFF Research Database (Denmark)

    Bugge, Merete

    2010-01-01

    Seven pairs of twins, two monozygotic (MZ), two dizygotic (DZ), and three like-sex pairs of unknown zygosity are described. The twin pairs were all discordant for omphalocele except for one pair of conjoined twins. The 8 infants with omphalocele represent 3.1% of the 253 infants with omphalocele......, ascertained in an almost complete nationwide data set of live- and stillborn infants with abdominal wall defects in two decades in Denmark (1970-1989). The occurrence of twins with omphalocele was not significantly different from the occurrence of twins in the Danish population in the same period. To our...... knowledge this is the first report of the occurrence of twins with omphalocele in a systematic nationwide epidemiological study....

  2. Vascular programming in twins: the effects of chorionicity and fetal therapy for twin-to-twin transfusion syndrome.

    Science.gov (United States)

    Gardiner, H M; Barlas, A; Matsui, H; Diemert, A; Taylor, M J O; Preece, J; Gordon, F; Greenwald, S E; Hecher, K

    2012-06-01

    We assessed vascular programming in genetically identical monochorionic twin pairs with twin-to-twin transfusion syndrome (TTTS) treated differently in utero by serial amnioreduction or fetal laser arterial photocoagulation. This case-control study re-assessed four twin groups at median 11 years comprising 20 pairs of monochorionic diamniotic twins: nine treated by amnioreduction (TTTS-amnio) and eleven by laser (TTTS-laser) with seven monochorionic and six dichorionic control pairs. Outcome measures were current blood pressure (BP), brachio-radial arterial stiffness derived from pulse wave velocity (PWV), resting microcirculation (Flux) and response to heating and post-occlusive reactive hyperaemia measured using laser Doppler. Potential confounders [PWV and BP at first study, current height, weight, heart rate and twin type (ex-recipient, ex-donor or heavier/lighter of pair)] were accounted for by Mixed Linear Models statistical methodology. PWV dichorionic > monochorionic (P = 0.024); systolic and diastolic BP dichorionic > TTTS-amnio and TTTS-laser (P = 0.004, P = 0.02 and P = 0.005, P = 0.02, respectively). Within-twin pair pattern of PWV discordance was similar in laser treated and dichorionic controls (heavier-born > lighter), opposite to TTTS-amnio and monochorionic controls. Flux monochorionic > dichorionic (P = 0.044) and heavier > lighter-born (P = 0.024). TTTS-laser and dichorionic diamniotic showed greatest hyperaemic responses (dichorionic > TTTS-amnio or monochorionic controls (P = 0.007, P = 0.025). Hyperaemic responses were slower in heavier-born twins (P = 0.005). In summary, monochorionic twins had lower BP, arterial stiffness and increased resting vasodilatation than dichorionic twins implying shared fetal circulation affects vascular development. Vascular responses in laser-TTTS were similar to dichorionic and opposite to TTTS-amnio suggesting a lasting effect of fetal therapy on vascular health.

  3. Operational Significance of Discord: Theory and Experiment

    CERN Document Server

    Gu, Mile; Assad, Syed M; Symul, Thomas; Modi, Kavan; Ralph, Timothy C; Vedral, Vlatko; Lam, Ping Koy

    2012-01-01

    Observations that coherent interactions between non-entangled systems can still exhibit unique quantum behaviour challenged the traditional view that quantum correlations are synonymous with entanglement. In response, quantum discord was proposed to complete the description of all quantum correlations. Nevertheless, explicit protocols that directly exploit discord as a quantum resource have remained elusive. Here, we demonstrate that under certain measurement constraints, discord between bipartite systems directly quantifies a quantum resource that coherent interactions can harness. The inability to access this resource by any other means allows us to use discord to directly quantify this `quantum advantage'. We experimentally encode information within the discordant correlations of two separable Gaussian states. The amount of extra information recovered by coherent interaction is quantified and directly linked with the discord between the states. No entanglement exists at any point of this experiment. Thus w...

  4. Interpreting Quantum Discord in Quantum Metrology

    OpenAIRE

    Girolami, Davide

    2015-01-01

    Multipartite quantum systems show properties which do not admit a classical explanation. In particular, even nonentangled states can enjoy a kind of quantum correlations called quantum discord. I discuss some recent results on the role of quantum discord in metrology. Given an interferometric phase estimation protocol where the Hamiltonian is initially unknown to the experimentalist, the quantum discord of the probe state quantifies the minimum precision of the estimation. This provides a phy...

  5. Quantum Discord of Non-X State

    Institute of Scientific and Technical Information of China (English)

    YAO Jing-Ying; DONG Yu-Li; ZHU Shi-Qun

    2013-01-01

    The level surfaces of quantum discord for a class of two-qubit states are investigated when the Bloch vectors (r) and (s) are perpendicularly oriented.The geometric objects of tetrahedron T and octahedron O are deformed.The level surfaces of constant discord are formed by three interaction “tubes” along three orthogonal directions.They shrink to the center when the Bloch vectors are increased and are expanded and cut off by the state tetrahedron T when the quantum discord is increased.In the phase damping channel,the quantum discord keeps approximately a constant when the time increases.

  6. Fetal blood sampling in twin pregnancies. Prenatal diagnosis and management of 19 cases.

    Science.gov (United States)

    Cox, W L; Forestier, F; Capella-Pavlovsky, M; Daffos, F

    1987-01-01

    Twin pregnancies pose particular problems in both prenatal diagnosis and obstetric management. We present 19 twin pregnancies that underwent fetal blood sampling (FBS). The indications were mostly similar to those for singleton pregnancies, with both fetuses being sampled. There was one indication specific to twin pregnancies; disseminated intravascular coagulation in the retained twin after the death-in-utero (DIU) of the other. In 5 cases, only 1 twin was sampled; in 2 because the second twin was female in the diagnosis of an X-linked disorder; in 1 because of technical failure, and in 2 the other twin had predeceased. Eight pregnancies continued after the FBS delivering 2 live, healthy infants, though 5 were delivered before 37 weeks of gestation. In 7 cases there was a discordance in the diagnosis between the twins. In 3 of these cases the affected fetus underwent selective termination by air embolism; in 2 cases the pregnancies were continued and the affected twin not resuscitated; 1 pregnancy is still in progress, and 1 patient had a non-medically supervised termination of both twins in another country. Two patients miscarried within a week of the FBS. Two patients had only 1 living twin at the time of FBS; 1 had a second DIU a month after the FBS and the other a neonatal death at 11 days of age in an infant with severe porencephaly. FBS is technically feasible for similar indications as for singleton pregnancies though discordance in diagnosis raises specific management problems.

  7. The season of birth of schizophrenic, neurotic and psychiatrically normal twins.

    Science.gov (United States)

    Kendler, K S

    1982-08-01

    The quarter of birth of 536 schizophrenic, 1,991 neurotic and 12,085 psychiatrically normal twin pairs from the National Academy of Sciences-National Research Council Twin Registry was compared. When either all twin pairs, or only monozygotic or dizygotic twin pairs, were considered, no significant differences were found in the quarter of birth between the 3 groups. No difference in quarter of birth was found for twin pairs concordant versus discordant for schizophrenia. Despite the increased risk for intrauterine and perinatal complications in twin births, schizophrenic twins appear (at least) to be no more vulnerable than schizophrenic singletons to the seasonal gestation and birth-related insults which probably underlie the seasonality in schizophrenic births. Controlling for season of birth probably has little effect on the results of twin studies of schizophrenia.

  8. The Concordance and Heritability of Type 2 Diabetes in 34,166 Twin Pairs From International Twin Registers

    DEFF Research Database (Denmark)

    Willemsen, G.; Ward, K. J.; Bell, C. G.;

    2015-01-01

    studies worldwide need to pool their resources. The Discordant Twin (DISCOTWIN) consortium was established for this goal. Here, we describe the DISCOTWIN Consortium and present an analysis of type 2 diabetes (T2D) data in nearly 35,000 twin pairs. Seven twin cohorts from Europe (Denmark, Finland, Norway...... and medication use, fasting glucose and insulin measures, or medical records. The prevalence of T2D ranged from 2.6% to 12.3% across the cohorts depending on age, body mass index (BMI), and national diabetes prevalence. T2D discordance rate was lower for MZ (5.1%, range 2.9-11.2%) than for same-sex dizygotic (DZ......, the Netherlands, Spain, Sweden, and the United Kingdom) and one from Australia investigated the rate of discordance for T2D in same-sex twin pairs aged 45 years and older. Data were available for 34,166 same-sex twin pairs, of which 13,970 were MZ, with T2D diagnosis based on self-reported diagnosis...

  9. Twin study on transplacental-acquired antibodies and attention deficit/hyperactivity disorder - A pilot study

    DEFF Research Database (Denmark)

    Bilenberg, Niels; Hougaard, David; Norgaard-Pedersen, Bent;

    2011-01-01

    -18years) questionnaire data on hyperactivity and inattention was collected. Blood samples taken 5days after birth from 190 ADHD-score discordant pairs (15% MZ) were analyzed for antibodies. RESULTS: Pneumococcus Polysaccaride 14 (PnPs14) was present in the ADHD high scoring twin more often than......OBJECTIVE: We hypothesize that maternal transplacentally acquired antibodies may cause Attention Deficit/Hyperactivity Disorder (ADHD) symptoms years after birth, and tested the hypothesis in twins discordant for ADHD symptoms. METHOD: In a pre-screened sample of 7793 same sex twin pair's (4...... in the lower scoring twin (P=0.04). CONCLUSION: Although the study provides no strong support for the hypothesis, infection or immunological factors may be one among several causes of ADHD. The genetic control obtained in a twin design may reduce the exposure contrast and a larger sample is needed to further...

  10. Monoamniotic twins with one fetal anencephaly and cord entanglement diagnosed with three dimensional ultrasound at 14 weeks of gestation.

    Science.gov (United States)

    Jo, Yun Sung; Son, Hyun Joo; Jang, Dong Gyu; Kim, Narinay; Lee, Guisera

    2011-01-01

    A 29-year-old pregnant woman with parity 0-0-0-0 was diagnosed with monoamniotic twin pregnancy discordant for anencephaly at 14 weeks gestation. Umbilical cord entanglement, which is an important cause of fetal death in monoamniotic twins, was confirmed by three-dimensional ultrasound. Cesarean section was performed at 34 weeks of gestation, and the normal newborn infant was discharged without any complications. We report a case of monoamniotic twin pregnancy discordant for anencephaly and diagnosed with cord entanglement by three-dimensional ultrasound at 14 weeks of gestation, and now report it along with a literature review.

  11. Monoamniotic Twins with One Fetal Anencephaly and Cord Entanglement Diagnosed with Three Dimensional Ultrasound at 14 Weeks of Gestation

    Directory of Open Access Journals (Sweden)

    Yun Sung Jo, Hyun Joo Son, Dong Gyu Jang, Narinay Kim, Guisera Lee

    2011-01-01

    Full Text Available A 29-year-old pregnant woman with parity 0-0-0-0 was diagnosed with monoamniotic twin pregnancy discordant for anencephaly at 14 weeks gestation. Umbilical cord entanglement, which is an important cause of fetal death in monoamniotic twins, was confirmed by three-dimensional ultrasound. Cesarean section was performed at 34 weeks of gestation, and the normal newborn infant was discharged without any complications. We report a case of monoamniotic twin pregnancy discordant for anencephaly and diagnosed with cord entanglement by three-dimensional ultrasound at 14 weeks of gestation, and now report it along with a literature review.

  12. Quantum discord in spin-cluster materials

    CERN Document Server

    Yurischev, M A

    2011-01-01

    The total quantum correlation (discord) in Heisenberg dimers is expressed via the spin-spin correlation function, internal energy, specific heat or magnetic susceptibility. This allows one to indirectly measure the discord through neutron scattering, as well as calorimetric or magnetometric experiments. Using the available experimental data, we found the discord for a number of binuclear Heisenberg substances with both antiferro- and ferromagnetic interactions. For the dimerized antiferromagnet copper nitrate Cu(NO_3)_2*2.5H_2O, the three independent experimental methods named above lead to a discord of approximately 0.2-0.3 bit/dimer at a temperature of 4 K. We also determined the temperature behavior of discord for hydrated and anhydrous copper acetates, as well as for the ferromagnetic binuclear copper acetate complex [Cu_2L(OAc)]*6H_2O, where L is a ligand.

  13. Role of quantum discord in quantum communication

    CERN Document Server

    Madhok, Vaibhav

    2011-01-01

    Positivity of quantum discord is shown to be equivalent to the strong sub additivity of the Von-Nuemann entropy. This leads to a connection between the mother protocol of quantum information theory [A. Abeyesinghe, I. Devetak, P. Hayden, and A. Winter, Proc. R. Soc. A 465, 2537, (2009)] and quantum discord. We exploit this to show that quantum discord is a measure coherence in the performance of the mother protocol. Since the mother protocol is a unification of an important class of problems (those that are bipartite, unidirectional and memoryless), we show quantum discord to be a measure of coherence in these protocols. Our work generalizes an earlier operational interpretation of quantum discord provided in terms of quantum state merging [V. Madhok and A. Datta, Phys. Rev. A 83, 032323, (2011)].

  14. Twin Baryogenesis

    CERN Document Server

    Farina, Marco; Shin, Chang Sub

    2016-01-01

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

  15. Angiographic studies of atrioventricular discordance.

    Science.gov (United States)

    Attie, F; Soni, J; Ovseyevitz, J; Muñoz-Castellanos, L; Testelli, M R; Buendia, A

    1980-08-01

    The results and value of conventional and axial angiocardiography were studied in 26 cases of atrioventricular discordance (AVD). The angiographic anatomy of this malformation was analyzed to determine the precise characteristics of atrioventricular and ventriculoarterial connections. The left and right ventricles in atrial situs solitus and levocardia show angiographic features that differ from those seen in atrial situs solitus and dextrocardia. The same differences are found in atrial situs inversus. Regardless of the type of ventriculoarterial connections, the ventricles maintain the same angiographic characteristics. The ventricular septum in AVD in situs solitus and levocardia and situs inversus and dextrocardia has a peculiar orientation. The use of axial angiocardiography facilitates detection and localization of the ventricular septal defect. In cases of malposition of the heart, the conventional frontal view allows visualization of the ventricular septum in all of its length. The axial projection is useful in diagnosing left ventricular outflow tract obstruction.

  16. 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...

  17. One-way unlocalizable quantum discord

    Science.gov (United States)

    Xi, Zhengjun; Fan, Heng; Li, Yongming

    2012-05-01

    In this paper, we present the concept of the one-way unlocalizable quantum discord and investigate its properties. We provide a polygamy inequality for it in a tripartite pure quantum system of arbitrary dimension. Several tradeoff relations between the one-way unlocalizable quantum discord and other correlations are given. If the von Neumann measurement is made on a part of the system, we give two expressions of the one-way unlocalizable quantum discord in terms of partial distillable entanglement and quantum disturbance. Finally, we also provide a lower bound for bipartite shareability of quantum correlation beyond entanglement in a tripartite system.

  18. The one-way unlocalizable quantum discord

    CERN Document Server

    Xi, Zhengjun; Li, Yongming

    2012-01-01

    In this paper, we present the concept of the one-way unlocalizable quantum discord and investigate its properties. We provide a polygamy inequality for it in tripartite pure quantum system of arbitrary dimension. Several trade-offs between the one-way unlocalizable quantum discord and other correlations are given. If the von Neumann measurement is on a part of the system, we give two expressions of the one-way unlocalizable quantum discord in terms of partial distillable entanglement and quantum disturbance. Finally, we also provide a lower bound for bipartite shareability of quantum correlation beyond entanglement in a tripartite system.

  19. Danish cohort of monozygotic inflammatory bowel disease twins: Clinical characteristics and inflammatory activity

    Science.gov (United States)

    Moller, Frederik Trier; Knudsen, Lina; Harbord, Marcus; Satsangi, Jack; Gordon, Hannah; Christiansen, Lene; Christensen, Kaare; Jess, Tine; Andersen, Vibeke

    2016-01-01

    AIM: To describe the establishment of a Danish inflammatory bowel diseases (IBD) twin cohort with focus on concordance of treatment and inflammatory markers. METHODS: We identified MZ twins, likely to be discordant or concordant for IBD, by merging information from the Danish Twin Register and the National Patient Register. The twins were asked to provide biological samples, questionnaires, and data access to patient files and public registries. Biological samples were collected via a mobile laboratory, which allowed for immediate centrifugation, fractionation, and storage of samples. The mean time from collection of samples to storage in the -80 °C mobile freezer was less than one hour. The diagnoses where validated using the Copenhagen diagnostic criteria. RESULTS: We identified 159 MZ IBD twin pairs, in a total of 62 (39%) pairs both twins agreed to participate. Of the supposed 62 IBD pairs, the IBD diagnosis could be confirmed in 54 pairs. The cohort included 10 concordant pairs, whereof some were discordant for either treatment or surgery. The 10 concordant pairs, where both pairs suffered from IBD, included eight CD/CD pairs, one UC/UC pair and one UC/IBDU pair. The discordant pairs comprised 31 UC, 5 IBDU (IBD unclassified), and 8 CD discordant pairs. In the co-twins not affected by IBD, calprotectin was above 100 μg/g in 2 participants, and above 50 μg/g in a further 5 participants. CONCLUSION: The presented IBD twin cohorts are an excellent resource for bioinformatics studies with proper adjustment for disease-associated exposures including medication and inflammatory activity in the co-twins. PMID:27275097

  20. Discord under the influence of a quantum phase transition

    Institute of Scientific and Technical Information of China (English)

    Wang Lin-cheng; Shen Jian; Yi Xue-Xi

    2011-01-01

    This paper studies the discord of a bipartite two-level system coupling to an XY spin-chain environment in a transverse field and investigates the relationship between the discord property and the environment's quantum phase transition. The results show that the quantum discord is also able to characterize the quantum phase transitions. We also discuss the difference between discord and entanglement, and show that quantum discord may reveal more general information than quantum entanglement for characterizing the environment's quantum phase transition.

  1. Heredity and environment in schizophrenia, revisited. The contribution of twin and high-risk studies.

    Science.gov (United States)

    Stabenau, J R; Pollin, W

    1993-05-01

    Life history study of monozygotic (MZ) twins discordant for schizophrenia led to the 1967 hypothesis that phenotypic schizophrenia was an expression of genotypic vulnerability interacting with prenatal and/or perinatal environmental experience. This report is a selected review of partial answers to five questions facing research efforts that have attempted to clarify the interactive gene-environment model of schizophrenia. Follow-up study of the offspring of MZ twins with a diagnosis of schizophrenia and their MZ co-twins without schizophrenia demonstrated equal rates of schizophrenia; hence, each group of offspring carried equal genetic vulnerability for schizophrenia. Magnetic resonance imaging study of MZ discordant twins found that phenotypic schizophrenia was characterized by brain ventricular enlargement and hippocampal reduction in 87-93% of the schizophrenic twins, when compared with their nonschizophrenic co-twins. A longitudinal study of teenage children at differential risk for schizophrenia showed that brain ventricular enlargement in adulthood correlated significantly and positively with genetic risk for schizophrenia and number of perinatal complications, and negatively with birth weight. Significantly greater dysmorphological hand skin signs among schizophrenic MZ twins when compared with their nonschizophrenic co-twins have suggested an in utero second trimester fetal developmental abnormality for the schizophrenic subjects. Simultaneous neuroanatomic, neurophysiological, and neurocognitive evaluation of MZ twin pairs discordant for schizophrenia demonstrated decreased prefrontal physiological cerebral blood flow activation during Wisconsin Card Sorting Test for affected twins correlated with decreased hippocampal volume determined by magnetic resonance imaging. These neurocognitive studies have suggested that schizophrenia involves neocortical-limbic pathology and dysfunction implicated in performance of cognitive tasks requiring working memory

  2. Guidelines for scanning twins and triplets with US and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Calvo-Garcia, Maria A. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2016-02-15

    Multiple-fetus gestations have an increased risk of discordant anomalies, aneuploidy and growth restriction compared to singleton pregnancies. In addition, twins sharing the same placenta are at risk for developing specific conditions that are potentially amenable to surgical management. In those scenarios, patients might need to be evaluated not only with US but with fetal MRI as well. This paper outlines basic guidelines to consider when imaging complicated multiple-fetus gestations during the 2nd and 3rd trimesters. (orig.)

  3. Twin studies as a model for exploring the aetiology of autoimmune thyroid disease

    DEFF Research Database (Denmark)

    Brix, Thomas Heiberg; Hegedüs, Laszlo

    2012-01-01

    triggers such as cigarette smoking, birth characteristics, infection with Yersinia enterocolitica, microchimerism and degree of X chromosome inactivation (XCI) has been evaluated by investigating AITD discordant twin pairs. These studies indicate that smoking, Y. enterocolitica infection and skewed XCI may...

  4. Quantum discord in de Sitter space

    CERN Document Server

    Kanno, Sugumi; Soda, Jiro

    2016-01-01

    We study quantum discord between two free modes of a massive scalar field in a maximally entangled state in de Sitter space. We introduce two observers, one in a global chart and the other in an open chart of de Sitter space, and the observers determine the quantum discord created by each detecting one of the modes. This situation is analogous to the relationship between an observer in a Minkowski chart and another in one of the two Rindler charts in flat space. We find that the state becomes less entangled as the curvature of the open chart gets larger. In particular, for the cases of a massless, and a conformally coupled scalar field, the entanglement vanishes in the limit of infinite curvature. However, we find that the quantum discord never disappears even in the limit that entanglement disappears.

  5. Geometric measure of quantum discord under decoherence

    CERN Document Server

    Xiao-Ming, Lu; Sun, Zhe; Wang, Xiaoguang

    2010-01-01

    The dynamics of a geometric measure of the quantum discord (GMQD) under decoherence is investigated. We show that the GMQD of a two-qubit state can be alternatively obtained through the singular values of a 3\\times4 matrix whose elements are the expectation values of Pauli matrices of the two qubits. By using Heisenberg picture, the analytic results of the GMQD is obtained for three typical kinds of the quantum decoherence channels. We compare the dynamics of the GMQD with that of the quantum discord and of entanglement and show that a sudden change in the decay rate of the GMQD does not always imply the sudden change in the decay rate of the quantum discord.

  6. The Qingdao Twin Registry

    DEFF Research Database (Denmark)

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

    2013-01-01

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

  7. Twin Jet

    Science.gov (United States)

    Henderson, Brenda; Bozak, Rick

    2010-01-01

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

  8. Parental Marital Discord and Treatment Response in Depressed Adolescents

    Science.gov (United States)

    Amaya, Meredith M.; Reinecke, Mark A.; Silva, Susan G.; March, John S.

    2011-01-01

    Evidence suggests that parental marital discord contributes to the development of internalizing and externalizing symptoms in children and adolescents. Few studies, however, have examined the association between parental marital discord and youth's response to treatment. The present study examined the impact of interparental discord on treatment…

  9. Entanglement as minimal discord over state extensions

    Science.gov (United States)

    Luo, Shunlong

    2016-09-01

    The characterization and quantification of quantum correlations, which play an instrumental role in exploring and exploiting the quantum world, have been extensively and intensively studied in the past few decades. Of special prominence and significance are the concepts of entanglement and discord, which are usually regarded as very distinctive quantum correlations, with the latter going beyond the former. In this work we establish a direct and natural link between entanglement and discord via state extensions and reveal that entanglement is actually the intrinsic discord, by which we mean that entanglement is the irreducible residue of discord viewed from ambient spaces. Our approach, taking into account the contextuality of a quantum state and being of a global nature, stands in sharp contrast to the local operations and classical communication paradigm of entanglement, which focuses on the state itself via a local approach. Furthermore, we introduce a figure of merit which, on the one hand, captures the essence of entanglement, i.e., nonlocality and quantumness of correlations, and, on the other hand, leads to a quantitative decomposition of total correlations into classical correlations, dissonance, and entanglement. This demystifies the meaning of entanglement from the perspective of quantum measurements and provides a unified framework for the interplay of various correlations in terms of quantum measurements and mutual information.

  10. Deformation twinning in monazite

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-10-20

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

  11. Association between physical and motor development in childhood: a longitudinal study of Japanese twins.

    Science.gov (United States)

    Silventoinen, Karri; Pitkäniemi, Janne; Latvala, Antti; Kaprio, Jaakko; Yokoyama, Yoshie

    2014-06-01

    Length and weight in infancy are associated with neurodevelopment, but less is known about growth in other anthropometric measures. In this study we analyzed how the development in length, weight, head circumference, and chest circumference over infancy is associated with motor development in early childhood, using a twin study design. Information on physical development over infancy and the age at achievement of eight developmental milestones over early childhood was collected for 370 Japanese twin pairs. Linear mixed models were used to analyze how physical development is associated with motor development between individual twins, as well as within twin pairs, adjusting the results for shared maternal and postnatal environmental factors. Delayed motor development was associated with smaller body size over infancy, and we also found some suggestive evidence that it was associated with catch-up growth as well. When studying the associations within twin pairs discordant for motor development, similar associations were found. However, chest circumference showed the most robust association within discordant twin pairs. Smaller body size and rapid catch-up growth are associated with delayed motor development. When studying these associations within twin pairs and thus adjusting the results for gestational age as well as many other maternal and postnatal environmental factors, chest circumference showed the most robust association. Chest circumference, rarely used in developed countries, can offer additional information on prenatal conditions relevant for further motor development not achieved by more traditional anthropometric measures.

  12. The Norwegian Twin Registry.

    Science.gov (United States)

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

    2012-12-01

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

  13. Discordant HIV couple: Analysis of the possible contributing factors

    Directory of Open Access Journals (Sweden)

    B C Ravikumar

    2013-01-01

    Full Text Available Several intricacies still abound with respect to HIV infection. Discordance is one such intriguing aspect of HIV infection. Out of 35 discordant couples included in the study. husbands were positive in 29 couples and wives in 6. Pre/extramarital affairs was the probable reason for HIV infection in 23 out of 29 discordant males, and 2 out of 6 discordant females. Even though, decreased frequency of sexual acts between the couple was the reason for discordance in a few, but in majority of the couples who had regular sexual contact for many years, the exact cause for discordance could not be ascertained. inherent resistance to HIV in some individuals may be the reasons for the discordance.

  14. The Danish Twin Register

    DEFF Research Database (Denmark)

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

    1996-01-01

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

  15. Monochorionic twin pregnancies

    NARCIS (Netherlands)

    Hack, K.E.A.

    2008-01-01

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

  16. The Danish Twin Registry

    DEFF Research Database (Denmark)

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

    2011-01-01

    Introduction: The Danish Twin Registry is a unique source for studies of genetic, familial and environmental factors on life events, health conditions and diseases. Content: More than 85,000 twin pairs born 1870-2008 in Denmark. Validity and coverage: Four main ascertainment methods have been...... employed. Completeness of ascertainment varies according to birth cohorts. For birth cohorts 1870-1930 both twins should survive to age 6 years. From 1931-1968 72% of all twin pairs has been ascertained, with complete ascertainment of all live born twins since 1968. CONCLUSION: Because twins have been...... identified independent of traits and on a population basis, the Danish Twin Registry is well suited for studies to understand the influence of genetic and environmental factors for a wide variety of diseases and traits....

  17. Measurement-based method for verifying quantum discord

    Science.gov (United States)

    Rahimi-Keshari, Saleh; Caves, Carlton M.; Ralph, Timothy C.

    2013-01-01

    We introduce a measurement-based method for verifying quantum discord of any bipartite quantum system. We show that by performing an informationally complete positive operator valued measurement (IC-POVM) on one subsystem and checking the commutativity of the conditional states of the other subsystem, quantum discord from the second subsystem to the first can be verified. This is an improvement upon previous methods, which enables us to efficiently apply our method to continuous-variable systems, as IC-POVM's are readily available from homodyne or heterodyne measurements. We show that quantum discord for Gaussian states can be verified by checking whether the peaks of the conditional Wigner functions corresponding to two different outcomes of heterodyne measurement coincide at the same point in the phase space. Using this method, we also prove that the only Gaussian states with zero discord are product states; hence, Gaussian states with Gaussian discord have nonzero quantum discord.

  18. Relating quantum discord with the quantum dense coding capacity

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xin; Qiu, Liang, E-mail: lqiu@cumt.edu.cn; Li, Song; Zhang, Chi [China University of Mining and Technology, School of Sciences (China); Ye, Bin [China University of Mining and Technology, School of Information and Electrical Engineering (China)

    2015-01-15

    We establish the relations between quantum discord and the quantum dense coding capacity in (n + 1)-particle quantum states. A necessary condition for the vanishing discord monogamy score is given. We also find that the loss of quantum dense coding capacity due to decoherence is bounded below by the sum of quantum discord. When these results are restricted to three-particle quantum states, some complementarity relations are obtained.

  19. Cerebral asymmetry in twins: predictions of the right shift theory.

    Science.gov (United States)

    Annett, Marian

    2003-01-01

    A study of the heritability of lobar brain volumes in twins has introduced a new approach to questions about the genetics of cerebral asymmetry. In addition to the classic comparison between monozygotic (MZ) and dizygotic (DZ) twins, a contrast was made between pairs of two right-handers (RR pairs) and pairs including one or more non-right-hander (non-RR pairs), in the light of the right shift (RS) theory of handedness. This paper explains the predictions of the RS model for pair concordance for genotype, cerebral asymmetry and handedness in healthy MZ and DZ twins. It shows how predictions for cerebral asymmetry vary between RR and non-RR pairs over a range of incidences of left-handedness. Although MZ twins are always concordant for genotype and DZ twins may be discordant, differences for handedness and cerebral asymmetry are expected to be small, consistent with the scarcity of significant effects in the literature. Marked differences between RR and non-RR pairs are predicted at all levels of incidence, the differences slightly larger in MZ than DZ pairs.

  20. Malaysian Twin Registry.

    Science.gov (United States)

    Jahanfar, Shayesteh; Jaffar, Sharifah Halimah

    2013-02-01

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

  1. 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.

  2. Does educational status impact adult mortality in Denmark? A twin approach

    DEFF Research Database (Denmark)

    Madsen, Mia; Andersen, Anne-Marie Nybo; Christensen, Kaare;

    2010-01-01

    design. The study is based on data from the Danish Twin Registry and Statistics Denmark. Using Cox regression, they estimated hazard ratios for mortality according to the highest attained education among 5,260 monozygotic and 11,088 dizygotic same-sex twin pairs born during 1921-1950 and followed during......To disentangle an independent effect of educational status on mortality risk from direct and indirect selection mechanisms, the authors used a discordant twin pair design, which allowed them to isolate the effect of education by means of adjustment for genetic and environmental confounding per......-1935, and no effect modification by zygosity was observed. Hence, the results are most compatible with an effect of early family environment in explaining the educational inequality in mortality. However, large educational differences were still reflected in mortality risk differences within twin pairs, thus...

  3. A study of diabetes mellitus within a large sample of Australian twins

    DEFF Research Database (Denmark)

    Condon, Julianne; Shaw, Joanne E; Luciano, Michelle;

    2008-01-01

    with type 2 diabetes (T2D), 41 female pairs with gestational diabetes (GD), 5 pairs with impaired glucose tolerance (IGT) and one pair with MODY. Heritabilities of T1D, T2D and GD were all high, but our samples did not have the power to detect effects of shared environment unless they were very large......Twin studies of diabetes mellitus can help elucidate genetic and environmental factors in etiology and can provide valuable biological samples for testing functional hypotheses, for example using expression and methylation studies of discordant pairs. We searched the volunteer Australian Twin...... Registry (19,387 pairs) for twins with diabetes using disease checklists from nine different surveys conducted from 1980-2000. After follow-up questionnaires to the twins and their doctors to confirm diagnoses, we eventually identified 46 pairs where one or both had type 1 diabetes (T1D), 113 pairs...

  4. The Brazilian Twin Registry.

    Science.gov (United States)

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

    2016-12-01

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

  5. Delivery in Twin Gestation

    Directory of Open Access Journals (Sweden)

    Mark T. Peters

    1995-01-01

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

  6. Management of Fetal Growth Arrest in One of Dichorionic Twins: Three Cases and a Literature Review

    Directory of Open Access Journals (Sweden)

    Shoji Kaku

    2015-01-01

    Full Text Available Progressive fetal growth restriction (FGR is often an indication for delivery. In dichorionic diamniotic (DD twin pregnancy with growth restriction only affecting one fetus (selective fetal growth restriction: sFGR, the normal twin is also delivered prematurely. There is still not enough evidence about the optimal timing of delivery for DD twins with sFGR in relation to discordance and gestational age. We report three sets of DD twins with sFGR (almost complete growth arrest affecting one fetus for ≥2 weeks before 30 weeks of gestation. The interval from growth arrest to delivery was 21–24 days and the discordance was 33.7–49.8%. A large-scale study showed no difference of overall mortality or the long-term outcome between immediate and delayed delivery for FGR, while many studies have identified a risk of developmental delay following delivery of the normal growth fetus before 32 weeks. Therefore, delivery of DD twins with sFGR should be delayed if the condition of the sFGR fetus permits in order to increase the gestational age of the normal growth fetus.

  7. Multipartite distribution property of one way discord beyond measurement

    Science.gov (United States)

    Liu, Si-Yuan; Zhang, Yu-Ran; Yang, Wen-Li; Fan, Heng

    2015-03-01

    We investigate the distribution property of one way discord in the multipartite system by introducing the concept of polygamy deficit for one way discord. The difference between one way discord and quantum discord is analogue to the one between entanglement of assistance and entanglement of formation. For tripartite pure states, two kinds of polygamy deficits are presented with the equivalent expressions and physical interpretations regardless of measurement. For four-partite pure states, we provide a condition which makes one way discord polygamy satisfied. In addition, we generalize these results to the case for N-partite pure states. Those results can be applicable to multipartite quantum systems and are complementary to our understanding of the shareability of quantum correlations.

  8. EFFECTS OF LONG-TERM PHYSICAL ACTIVITY ON CARDIAC STRUCTURE AND FUNCTION: A TWIN STUDY

    Directory of Open Access Journals (Sweden)

    Urho M.Kujala

    2009-12-01

    Full Text Available Previous studies have shown that athletic training or other physical activity causes structural and functional adaptations in the heart, but less is known how long-term physical activity affects heart when genetic liability and childhood environment are taken into account. The aim of this study was to investigate the effects of long-term physical activity vs. inactivity on cardiac structure and function in twin pairs discordant for physical activity for 32 years. Twelve same-sex twin pairs (five monozygotic and seven dizygotic, 50-67 years were studied as a part of the TWINACTIVE study. Discordance in physical activity was initially determined in 1975 and it remained significant throughout the follow-up. At the end of the follow-up in 2007, resting echocardiographic and electrocardiographic measurements were performed. During the follow-up period, the active co-twins were on average 8.2 (SD 4.0 MET hours/day more active than their inactive co-twins (p < 0.001. At the end of the follow-up, resting heart rate was lower in the active than inactive co-twins [59 (SD 5 vs. 68 (SD 10 bpm, p=0.03]. The heart rate-corrected QT interval was similar between the co-twins. Also, there was a tendency for left ventricular mass per body weight to be greater and T wave amplitude in lead II to be higher in the active co-twins (18% and 15%, respectively, p=0.08 for both. Similar trends were found for both monozygotic and dizygotic twin pairs. In conclusion, the main adaptation to long- term physical activity is lowered resting heart rate, even after partially or fully controlling for genetic liability and childhood environment

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

    Directory of Open Access Journals (Sweden)

    Karien E A Hack

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

  10. Twin anemia polycythemia sequence

    NARCIS (Netherlands)

    Slaghekke, Femke

    2014-01-01

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

  11. Clinical characteristics of fetal and neonatal outcomes in twin pregnancy with preeclampsia in a retrospective case–control study

    Science.gov (United States)

    Yuan, Ting; Wang, Wei; Li, Xue-Lan; Li, Chun-Fang; Li, Chao; Gou, Wen-Li; Han, Zhen

    2016-01-01

    Abstract The aim of our study was to compare the clinical characteristics of fetal and neonatal outcomes in twin pregnancies between women with preeclampsia (PE) and those with normotension in a Chinese population. There were 143 preeclamptic women and 367 normotensive women with twin pregnancies included in this retrospective case–control study. The baseline characteristics and perinatal outcomes were collected and compared between the groups. Multiple logistic regression and linear regression were used to assess the correlations between PE and the outcomes. Significant increases were observed in the frequencies of preterm delivery (OR = 2.75, P < 0.001), iatrogenic preterm birth (OR = 3.52, P < 0.001), and IUGR (OR = 2.94, P = 0.001) in the PE group, and the PE group had more than a 2-fold risk of adverse neonatal outcomes. Preeclamptic twin neonates had lower birth weights (β = −147.34, P = 0.005; β = −169.47, P = 0.001). The comparison on the discordance of intertwin weight was not significantly different. Twin pregnancies with PE are associated with worse perinatal outcomes. The adverse outcomes of preeclamptic twin pregnancies may be associated with lower birth weights rather than the discordance of the intertwin weight, which requires further confirmation. The results may provide helpful references for better clinical assessments, evaluations of prognosis, and a deeper understanding of preeclamptic twin pregnancies. PMID:27787375

  12. Circulating MicroRNAs and Life Expectancy Among Identical Twins.

    Science.gov (United States)

    Wu, Shenghui; Kim, Taek-Kyun; Wu, Xiaogang; Scherler, Kelsey; Baxter, David; Wang, Kai; Krasnow, Ruth E; Reed, Terry; Dai, Jun

    2016-09-01

    Human life expectancy is influenced not only by longevity assurance mechanisms and disease susceptibility loci but also by the environment, gene-environment interactions, and chance. MicroRNAs (miRNAs) are a class of small noncoding RNAs closely related to genes. Circulating miRNAs have been shown as promising noninvasive biomarkers in the development of many pathophysiological conditions. However, the concentration of miRNA in the circulation may also be affected by environmental factors. We used a next-generation sequencing platform to assess the association of circulating miRNA with life expectancy, for which deaths are due to all causes independent of genes. In addition, we showed that miRNAs are present in 41-year archived plasma samples, which may be useful for both life expectancy and all-cause mortality risk assessment. Plasma miRNAs from nine identical male twins were profiled using next-generation sequencing. The average absolute difference in the minimum life expectancy was 9.68 years. Intraclass correlation coefficients were above 0.4 for 50% of miRNAs. Comparing deceased twins with their alive co-twin brothers, the concentrations were increased for 34 but decreased for 30 miRNAs. Identical twins discordant in life expectancy were dissimilar in the majority of miRNAs, suggesting that environmental factors are pivotal in miRNAs related to life expectancy.

  13. Resolution of superimposed pre-eclampsia, and improvement in umbilical artery flow in a surviving twin after intrauterine demise of its co-twin.

    Science.gov (United States)

    Narasimhulu, Deepa M; Karakash, Scarlett; Rankin, Linda; Minkoff, Howard

    2015-09-01

    Pre-eclampsia has a progressive clinical course, and is only cured by delivery of the placenta. We report a 30-year-old G1P0 with dichorionic twins, discordant growth and chronic hypertension who developed superimposed pre-eclampsia in her 21st week of gestation. After intrauterine demise of the severely growth-restricted twin, the superimposed pre-eclampsia resolved. The surviving twin initially had absent end diastolic flow, which resolved after the demise. A healthy 1935-g neonate with Apgar 9/9 was delivered at 34 weeks. Antenatal resolution of pre-eclampsia is extremely rare and resolution of superimposed pre-eclampsia has not, to our knowledge, been reported.

  14. Discord as a quantum resource for bi-partite communication

    Energy Technology Data Exchange (ETDEWEB)

    Chrzanowski, Helen M.; Assad, Syed M.; Symul, Thomas; Lam, Ping Koy [Centre for Quantum Computation and Communication Technology, Department of Quantum Science, The Australian National University (Australia); Gu, Mile; Modi, Kavan; Vedral, Vlatko [Centre for Quantum Technologies, National University of Singapore (Singapore); Ralph, Timothy C. [Centre for Quantum Computation and Communication Technology, Department of Physics, University of Queensland (Australia)

    2014-12-04

    Coherent interactions that generate negligible entanglement can still exhibit unique quantum behaviour. This observation has motivated a search beyond entanglement for a complete description of all quantum correlations. Quantum discord is a promising candidate. Here, we experimentally demonstrate that under certain measurement constraints, discord between bipartite systems can be consumed to encode information that can only be accessed by coherent quantum interactions. The inability to access this information by any other means allows us to use discord to directly quantify this ‘quantum advantage’.

  15. The role of quantum discord in quantum information theory

    Energy Technology Data Exchange (ETDEWEB)

    Streltsov, Alexander [ICFO - The Institute of Photonic Sciences, Castelldefels (Spain)

    2014-07-01

    Quantum correlations beyond entanglement - in particular represented by quantum discord - have become a major research field in the last few years. In this talk we report on the role of quantum discord in several fundamental tasks in quantum information theory. Starting with the role of quantum discord in the quantum measurement process, we also discuss its role in the tasks of information sharing and entanglement distribution. Finally, we also show the limits of these results and present possible ways to go beyond these limits.

  16. Genetic and experiential influences on behavior: Twins reunited at seventy-eight years.

    Science.gov (United States)

    Segal, Nancy L; Cortez, Franchesca A; Zettel-Watson, Laura; Cherry, Barbara J; Mechanic, Mindy; Munson, Jaimee E; Velázquez, Jaime M A; Reed, Brandon

    2015-01-01

    Twins living in different countries offer opportunities to explore associations between observed differences and experiential effects. This report compared the life histories, cognitive abilities, personality traits, psychomotor skills, medical characteristics, job satisfaction, social support and social relations of dizygotic (DZ) female twins reunited at 78, the world's longest separated set. The twins' advanced age also enabled a study of how co-twin differences in aging may be associated with current behavioral and social differences. Consistent with previous studies, these dizygotic reared apart (DZA) twins showed discordance across some, but not all, traits. Their different rearing situations and life histories may explain current differences in their responses to meeting their twin. This case highlights the importance of both genetic and rearing factors on behavior, but does not allow firm conclusions regarding the extent to which these sources explain individual developmental differences. However, such data contribute to the growing number of cross-culturally separated twins, generating novel hypotheses that may be assessed using larger samples.

  17. SUSY Meets Her Twin

    CERN Document Server

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

    2017-01-01

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

  18. SUSY Meets Her Twin

    CERN Document Server

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

    2016-01-01

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

  19. Is Chronic Low Back Pain Associated with the Prevalence of Coronary Heart Disease when Genetic Susceptibility Is Considered? A Co-Twin Control Study of Spanish Twins

    Science.gov (United States)

    Fernandez, Matt; Ordoñana, Juan R.; Hartvigsen, Jan; Ferreira, Manuela L.; Refshauge, Kathryn M.; Sánchez-Romera, Juan F.; Pinheiro, Marina B.; Simpson, Stephen J.; Hopper, John L.; Ferreira, Paulo H.

    2016-01-01

    Objective To investigate the chronic low back pain and coronary heart disease relationship, after adjusting for relevant confounders, including genetics. Methods In a cross-sectional design, 2148 twins were recruited from the Murcia Twin Registry, Spain. The exposure was chronic LBP and the outcomes were myocardial infarction and other coronary heart diseases—lifetime and in the last 2 years–based on standardized health-related questionnaires. First, logistic regression analysis investigated associations of the total sample followed by a matched co-twin control analyses, with all complete twin pairs discordant for chronic LBP utilised, separated for zygosity—dizygotic (DZ) and monozygotic (MZ) pairs, which adjusted for shared familial factors, including genetics. Results Chronic LBP pain is associated with lifetime myocardial infarction [odds ratio (OR) = 2.69, 95% confidence interval (CI) = 1.35–5.36], other coronary heart diseases over a lifetime (OR = 2.58, 95% CI: 1.69–3.93) and in the last two years (OR = 2.19, 95% CI: 1.33–3.60), while there was a borderline association with myocardial infarction in the last 2 years (OR = 2.64, 95% CI: 0.98–7.12). Although the magnitude of the association remained or increased in the co-twin control analyses, none reached statistical significance. Conclusion Chronic LBP is associated with a higher prevalence of myocardial infarction and coronary heart disease. It is possible that this association remains even when controlling for genetics and early shared environment, although this should be investigated with larger samples of twins discordant for LBP. PMID:27171210

  20. Gut DNA viromes of Malawian twins discordant for severe acute malnutrition

    Science.gov (United States)

    The bacterial component of the human gut microbiota undergoes a definable program of postnatal development. Evidence is accumulating that this program is disrupted in children with severe acute malnutrition (SAM) and that their persistent gut microbiota immaturity, which is not durably repaired with...

  1. Brain activation during cognitive planning in twins discordant or concordant for obsessive–compulsive symptoms

    OpenAIRE

    den Braber, Anouk; van ’t Ent, Dennis; Cath, Danielle C.; Wagner, Judith; Boomsma, Dorret I; de Geus, Eco J C

    2010-01-01

    Neuroimaging studies have indicated abnormalities in cortico-striatal-thalamo-cortical circuits in patients with obsessive–compulsive disorder compared with controls. However, there are inconsistencies between studies regarding the exact set of brain structures involved and the direction of anatomical and functional changes. These inconsistencies may reflect the differential impact of environmental and genetic risk factors for obsessive–compulsive disorder on different parts of the brain. To ...

  2. Whole blood BDNF levels in healthy twins discordant for affective disorder

    DEFF Research Database (Denmark)

    Trajkovska, Viktorija; Vinberg, Maj; Aznar, Susana

    2008-01-01

    and protected against affective disorder. Whole blood assessed for BDNF concentrations and correlated to risk status, neuroticism, and number of stressful life events. RESULTS: Between the groups, we found no significant difference in whole blood BDNF levels. Women at high-risk for depression who had...... neuroticism scores and two or less recent stressful events were associated with decreased whole blood BDNF levels (n=50, p

  3. Two cases of the caudal duplication anomaly including a discordant monozygotic twin

    NARCIS (Netherlands)

    Kroes, HY; Takahashi, M; Zijlstra, RJ; Baert, JALL; Kooi, KA; Hofstra, RMW; van Essen, AJ

    2002-01-01

    We present two unrelated patients with various duplications in the caudal region. One patient presented with a duplication of the distal spine from L4, left double ureter, duplication of the vagina and cervix, and duplication of the distal colon. The second patient was diagnosed with a duplication o

  4. A Discordant Monozygotic Twin Design Shows Blunted Cortisol Reactivity among Bullied Children

    Science.gov (United States)

    Ouellet-Morin, Isabelle; Danese, Andrea; Bowes, Lucy; Shakoor, Sania; Ambler, Antony; Pariante, Carmine M.; Papadopoulos, Andrew S.; Caspi, Avshalom; Moffitt, Terrie E.; Arseneault, Louise

    2011-01-01

    Objective: Childhood adverse experiences are known to engender persistent changes in stress-related systems and brain structures involved in mood, cognition, and behavior in animal models. Uncertainty remains about the causal effect of early stressful experiences on physiological response to stress in human beings, as the impact of these…

  5. Genes and Memory: The Neuroanatomical Correlates of Emotional Memory in Monozygotic Twin Discordant for Schizophrenia

    Science.gov (United States)

    Fahim, Cherine; Stip, Emmanuel; Mancini-Marie, Adham; Beauregard, Mario

    2004-01-01

    Background: Brain morphology and physiological measures in schizophrenia have yielded inconsistent results. This may be due in part to difficulties in ascertaining precisely to what degree each measure deviates from its genetically and environmentally determined potential level. We attempted to surmount this problem in a paradigm involving…

  6. Dermatoglyphics in relation to brain volumes in twins concordant and discordant for bipolar disorder

    NARCIS (Netherlands)

    Vonk, R.; van der Schot, A. C.; van Baal, G. C. M.; van Oel, C. J.; Nolen, W. A.; Kahn, R. S.

    2014-01-01

    Palmar and finger dermatoglyphics are formed between the 10th and the 17th weeks of gestation and their morphology can be influenced by genetic or environmental factors, interfering with normal intrauterine development. As both the skin and the brain develop from the same embryonal ectoderm, dermato

  7. Phenotypic discordance in a family with monozygotic twins and non-syndromic cleft lip and palate

    Energy Technology Data Exchange (ETDEWEB)

    Wyszynski, D.F. [Johns Hopkins Univ., Baltimore, MD (United States)]|[National Center for Human Genome Research, Bethesda, MD (United States); Lewanda, A.F. [Johnson Hopkins Hospital, Baltimore, MD (United States)]|[Children`s National Medical Center, Washington, DC (United States); Beaty, T.H. [Johns Hopkins Univ., Balitomre, MD (United States)

    1996-12-30

    Despite considerable research, the cause of non-syndromic cleft lip with or without cleft palate (NSCLP) is still an enigma. Case-control and cohort studies have searched for environmental factors that might influence the development of this common malformation, such as maternal cigarette smoking, periconceptional supplementation of folic acid and multivitamins, agricultural chemical use, and place of residence, among others. However, these studies are subject to numerous biases, and their results have often been contradictory and inconclusive. 41 refs., 1 fig.

  8. Mechanism of Discordant Alternans in Spatially Homogenoeus Tissue

    CERN Document Server

    Watanabe, M; Evans, S J; Hastings, H; Karma, A; Watanabe, Mari A.; Fenton, Flavio H; Evans, Steven J.; Hastings, Harold; Karma, Alain

    2000-01-01

    Discordant alternans,the phenomenon of 2 separate cardiac tissue locations exhibiting action potential duration (APD) alternans of opposite phase, appears to be a potential mechanism for electrocardiographic T wave alternans, but its initiation mechanism is unknown. We studied behavior of one- and two- dimensional cardiac tissue spatially homogenous in all respects, including APD restitution and conduction velocity restitution, using the Beeler Reuter ion channel model. We found that discordant alternans was initiated when spatial gradients of APD arose dynamically, such as from fixed rate pacing of a cable end (sinus node scenario), or from fixed rate pacing at one site preceded by a single excitation wavefront from another site (ectopic focus scenario). In the sinus node scenario, conduction velocity restitution was necessary to initiate discordant alternans. Alternating regimes of concordant and discordant alternans arose along the length of the cable, with regimes delimited by nodes of fixed APD. The numb...

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

    Directory of Open Access Journals (Sweden)

    Gerardo Rogelio Robaina Castellanos

    2016-10-01

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

  10. Fullerton Virtual Twin Study.

    Science.gov (United States)

    Segal, Nancy L

    2006-12-01

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

  11. Classicality from zero discord for continuous-variables bipartite systems

    CERN Document Server

    Arsenijevic, M; Dugic, M

    2012-01-01

    Quantum information resources quantified by non-zero discord are ubiquitous for the continuous-variables bipartite systems. Complementary to this, we investigate the zero-discord-defined classicality for the different structures (decompositions into subsystems) of such systems. We point out complexity and subtlety of the task and we construct a model-structure closely resembling the classical systems not supporting quantum information processing.

  12. Exercise — Exploring Mutuality and Discordance(s Between Sport and Public Health

    Directory of Open Access Journals (Sweden)

    Eling D. de Bruin

    2013-01-01

    Full Text Available Sports is a peer-reviewed scientific journal that revolves around the interdisciplinary area of exercise sciences applied in sport and public health. The intention of Sports is to link several scientific disciplines in an integrated fashion in order to address critical issues related to exercise science, sports and public health. As the first Editor-in-Chief of Sports, I would like to share a few comments about this interdisciplinary field of research by discussing the mutuality and discordances between exercise as it is applied in sports and public health.

  13. Risk factors for asthma in young adults: a co-twin control study

    DEFF Research Database (Denmark)

    Thomsen, SF; Ulrik, Charlotte Suppli; Kyvik, KO;

    2006-01-01

    . Pairs in which only one twin developed asthma -- discordant pairs -- were identified and conditional logistic regression was applied to detect effects of risk factors. RESULTS: A total of 126 monozygotic (MZ) and 273 dizygotic (DZ) discordant twin pairs were identified. In MZ twins hay fever (OR = 3.......16, 95% CI: 1.29-7.73, P = 0.007) and exercise (OR for inactivity = 0.35, 95% CI: 0.13-0.91, P = 0.023) were significantly associated with asthma, whereas in DZ twins, hay fever (OR = 2.44, 95% CI: 1.44-4.13, P = 0.001), eczema (OR = 1.96, 95% CI: 1.02-3.78, P = 0.040), female sex (OR between males...... and females = 0.54, 95% CI: 0.36-0.80, P = 0.002), and increasing levels of body mass index (BMI; OR per unit = 1.11, 95% CI: 1.02-1.20, P = 0.009) were significant predictors of asthma. CONCLUSIONS: Hay fever, eczema, female sex, exercise and increasing levels of BMI were risk factors for asthma in young...

  14. Craniofacial anomalies in twins.

    Science.gov (United States)

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

    1991-01-01

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

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

    Science.gov (United States)

    Olofsson, P; Rydhström, H

    1985-11-01

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

  16. Somatosensory Brain Function and Gray Matter Regional Volumes Differ According to Exercise History: Evidence from Monozygotic Twins.

    Science.gov (United States)

    Hautasaari, Pekka; Savić, Andrej M; Loberg, Otto; Niskanen, Eini; Kaprio, Jaakko; Kujala, Urho M; Tarkka, Ina M

    2017-01-01

    Associations between long-term physical activity and cortical function and brain structure are poorly known. Our aim was to assess whether brain functional and/or structural modulation associated with long-term physical activity is detectable using a discordant monozygotic male twin pair design. Nine monozygotic male twin pairs were carefully selected for an intrapair difference in their leisure-time physical activity of at least three years duration (mean age 34 ± 1 years). We registered somatosensory mismatch response (SMMR) in EEG to electrical stimulation of fingers and whole brain MR images. We obtained exercise history and measured physical fitness and body composition. Equivalent electrical dipole sources of SMMR as well as gray matter (GM) voxel counts in regions of interest indicated by source analysis were evaluated. SMMR dipolar source strengths differed between active and inactive twins within twin pairs in postcentral gyrus, medial frontal gyrus and superior temporal gyrus and in anterior cingulate (AC) GM voxel counts differed similarly. Compared to active twins, their inactive twin brothers showed greater dipole strengths in short periods of the deviant-elicited SMMR and larger AC GM voxel counts. Stronger activation in early unattended cortical processing of the deviant sensory signals in inactive co-twins may imply less effective gating of somatosensory information in inactive twins compared to their active brothers. Present findings indicate that already in 30's long-term physical activity pattern is linked with specific brain indices, both in functional and structural domains.

  17. Sexually transmitted infections among HIV-1-discordant couples.

    Directory of Open Access Journals (Sweden)

    Brandon L Guthrie

    Full Text Available INTRODUCTION: More new HIV-1 infections occur within stable HIV-1-discordant couples than in any other group in Africa, and sexually transmitted infections (STIs may increase transmission risk among discordant couples, accounting for a large proportion of new HIV-1 infections. Understanding correlates of STIs among discordant couples will aid in optimizing interventions to prevent HIV-1 transmission in these couples. METHODS: HIV-1-discordant couples in which HIV-1-infected partners were HSV-2-seropositive were tested for syphilis, chlamydia, gonorrhea, and trichomoniasis, and HIV-1-uninfected partners were tested for HSV-2. We assessed sociodemographic, behavioral, and biological correlates of a current STI. RESULTS: Of 416 couples enrolled, 16% were affected by a treatable STI, and among these both partners were infected in 17% of couples. A treatable STI was found in 46 (11% females and 30 (7% males. The most prevalent infections were trichomoniasis (5.9% and syphilis (2.6%. Participants were 5.9-fold more likely to have an STI if their partner had an STI (P<0.01, and STIs were more common among those reporting any unprotected sex (OR = 2.43; P<0.01 and those with low education (OR = 3.00; P<0.01. Among HIV-1-uninfected participants with an HSV-2-seropositive partner, females were significantly more likely to be HSV-2-seropositive than males (78% versus 50%, P<0.01. CONCLUSIONS: Treatable STIs were common among HIV-1-discordant couples and the majority of couples affected by an STI were discordant for the STI, with relatively high HSV-2 discordance. Awareness of STI correlates and treatment of both partners may reduce HIV-1 transmission. TRIAL REGISTRATION: ClinicalTrials.gov NCT00194519.

  18. Regional differences in prevalence of HIV-1 discordance in Africa and enrollment of HIV-1 discordant couples into an HIV-1 prevention trial.

    Directory of Open Access Journals (Sweden)

    Jairam R Lingappa

    Full Text Available BACKGROUND: Most HIV-1 transmission in Africa occurs among HIV-1-discordant couples (one partner HIV-1 infected and one uninfected who are unaware of their discordant HIV-1 serostatus. Given the high HIV-1 incidence among HIV-1 discordant couples and to assess efficacy of interventions for reducing HIV-1 transmission, HIV-1 discordant couples represent a critical target population for HIV-1 prevention interventions and prevention trials. Substantial regional differences exist in HIV-1 prevalence in Africa, but regional differences in HIV-1 discordance among African couples, has not previously been reported. METHODOLOGY/PRINCIPAL FINDINGS: The Partners in Prevention HSV-2/HIV-1 Transmission Trial ("Partners HSV-2 Study", the first large HIV-1 prevention trial in Africa involving HIV-1 discordant couples, completed enrollment in May 2007. Partners HSV-2 Study recruitment data from 12 sites from East and Southern Africa were used to assess HIV-1 discordance among couples accessing couples HIV-1 counseling and testing, and to correlate with enrollment of HIV-1 discordant couples. HIV-1 discordance at Partners HSV-2 Study sites ranged from 8-31% of couples tested from the community. Across all study sites and, among all couples with one HIV-1 infected partner, almost half (49% of couples were HIV-1 discordant. Site-specific monthly enrollment of HIV-1 discordant couples into the clinical trial was not directly associated with prevalence of HIV-1 discordance, but was modestly correlated with national HIV-1 counseling and testing rates and access to palliative care/basic health care (r = 0.74, p = 0.09. CONCLUSIONS/SIGNIFICANCE: HIV-1 discordant couples are a critical target for HIV-1 prevention in Africa. In addition to community prevalence of HIV-1 discordance, national infrastructure for HIV-1 testing and healthcare delivery and effective community outreach strategies impact recruitment of HIV-1 discordant couples into HIV-1 prevention trials.

  19. Hypoalbuminemia in Donors with Twin-Twin Transfusion Syndrome

    NARCIS (Netherlands)

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

    2013-01-01

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

  20. Quantum discord for two-qubit X-states

    CERN Document Server

    Ali, Mazhar; Alber, Gernot

    2010-01-01

    Quantum discord, a kind of quantum correlation, is defined as the difference between quantum mutual information and classical correlation in a bipartite system. In general, this correlation is different from entanglement, and quantum discord may be nonzero even for certain separable states. Even in the simple case of bipartite quantum systems, this different kind of quantum correlation has interesting and significant applications in quantum information processing. So far, quantum discord has been calculated explicitly only for a rather limited set of two-qubit quantum states and expressions for more general quantum states are not known. In this paper, we derive explicit expressions for quantum discord for a larger class of two-qubit states, namely, a seven-parameter family of so called X-states that have been of interest in a variety of contexts in the field. We also study the relation between quantum discord, classical correlation, and entanglement for a number of two-qubit states to demonstrate that they ar...

  1. Measuring DQC1 Quantum Discord using DQC1

    CERN Document Server

    Passante, G; Laflamme, R

    2012-01-01

    We describe an efficient DQC1-algorithm to quantify the amount of Geometric Quantum Discord present in the output state of a DQC1 computation. DQC1 is a model of computation that utilizes separable states to solve a problem with no known efficient classical algorithm and is known to contain quantum correlations as measured by the discord. For the general case of a (1+n)-qubit DQC1-state we provide an analytical expression for the Geometric Quantum Discord and find that its typical (and maximum) value decreases exponentially with n. This is in contrast to the standard Quantum Discord whose value for typical DQC1-states is known to be independent of n. We experimentally demonstrate the proposed algorithm on a four-qubit liquid-state nuclear magnetic resonance quantum information processor. In the special case of a two-qubit DQC1 model, we also provide an expression for the Quantum Discord that only requires the outcome of the DQC1 algorithm.

  2. The Danish Twin Registry

    DEFF Research Database (Denmark)

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

    2013-01-01

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

  3. Dialysis for twins

    DEFF Research Database (Denmark)

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

    2014-01-01

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

  4. Experimental Investigation of the Evolution of Gaussian Quantum Discord in an Open System

    DEFF Research Database (Denmark)

    Madsen, Lars S.; Berni, Adriano; Lassen, Mikael;

    2012-01-01

    Gaussian quantum discord is a measure of quantum correlations in Gaussian systems. Using Gaussian discord, we quantify the quantum correlations of a bipartite entangled state and a separable two-mode mixture of coherent states. We experimentally analyze the effect of noise addition and dissipatio...... on Gaussian discord and show that the former noise degrades the discord, while the latter noise for some states leads to an increase of the discord. In particular, we experimentally demonstrate the near death of discord by noisy evolution and its revival through dissipation....

  5. Maternal nutrition in twin pregnancy.

    Science.gov (United States)

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

    1982-01-01

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

  6. Microbiota conservation and BMI signatures in adult monozygotic twins.

    Science.gov (United States)

    Tims, Sebastian; Derom, Catherine; Jonkers, Daisy M; Vlietinck, Robert; Saris, Wim H; Kleerebezem, Michiel; de Vos, Willem M; Zoetendal, Erwin G

    2013-04-01

    The human gastrointestinal (GI) tract microbiota acts like a virtual organ and is suggested to be of great importance in human energy balance and weight control. This study included 40 monozygotic (MZ) twin pairs to investigate the influence of the human genotype on GI microbiota structure as well as microbial signatures for differences in body mass index (BMI). Phylogenetic microarraying based on 16S rRNA genes demonstrated that MZ twins have more similar microbiotas compared with unrelated subjects (Ptwins. Half of the twin pairs were selected on discordance in terms of BMI, which revealed an inverse correlation between Clostridium cluster IV diversity and BMI. Furthermore, relatives of Eubacterium ventriosum and Roseburia intestinalis were positively correlated to BMI differences, and relatives of Oscillospira guillermondii were negatively correlated to BMI differences. Lower BMI was associated with a more abundant network of primary fiber degraders, while a network of butyrate producers was more prominent in subjects with higher BMI. Combined with higher butyrate and valerate contents in the fecal matter of higher BMI subjects, the difference in microbial networks suggests a shift in fermentation patterns at the end of the colon, which could affect human energy homeostasis.

  7. Imaging of conjoined twins

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-09-15

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

  8. Post-Markovian dynamics of quantum correlations: entanglement versus discord

    Science.gov (United States)

    Mohammadi, Hamidreza

    2017-02-01

    Dynamics of an open two-qubit system is investigated in the post-Markovian regime, where the environments have a short-term memory. Each qubit is coupled to separate environment which is held in its own temperature. The inter-qubit interaction is modeled by XY-Heisenberg model in the presence of spin-orbit interaction and inhomogeneous magnetic field. The dynamical behavior of entanglement and discord has been considered. The results show that quantum discord is more robust than quantum entanglement, during the evolution. Also the asymmetric feature of quantum discord can be monitored by introducing the asymmetries due to inhomogeneity of magnetic field and temperature difference between the reservoirs. By employing proper parameters of the model, it is possible to maintain nonvanishing quantum correlation at high degree of temperature. The results can provide a useful recipe for studying dynamical behavior of two-qubit systems such as trapped spin electrons in coupled quantum dots.

  9. Quantum discord and entanglement in grover search algorithm

    Science.gov (United States)

    Ye, Bin; Zhang, Tingzhong; Qiu, Liang; Wang, Xuesong

    2016-06-01

    Imperfections and noise in realistic quantum computers may seriously affect the accuracy of quantum algorithms. In this article we explore the impact of static imperfections on quantum entanglement as well as non-entangled quantum correlations in Grover's search algorithm. Using the metrics of concurrence and geometric quantum discord, we show that both the evolution of entanglement and quantum discord in Grover algorithm can be restrained with the increasing strength of static imperfections. For very weak imperfections, the quantum entanglement and discord exhibit periodic behavior, while the periodicity will most certainly be destroyed with stronger imperfections. Moreover, entanglement sudden death may occur when the strength of static imperfections is greater than a certain threshold.

  10. Discordance between patient and surgeon satisfaction after total joint arthroplasty.

    Science.gov (United States)

    Harris, Ian A; Harris, Anita M; Naylor, Justine M; Adie, Sam; Mittal, Rajat; Dao, Alan T

    2013-05-01

    We surveyed 331 patients undergoing total hip or knee arthroplasty pre-operatively, and patients and surgeons were both surveyed 6 and 12 months post-operatively. We identified variables (demographic factors, operative factors and patient expectations) as possible predictors for discordance in patient-surgeon satisfaction. At 12 months, 94.5% of surgeons and 90.3% of patients recorded satisfaction with the outcome. The discordance between patient and surgeon satisfaction was mainly due to patient dissatisfaction-surgeon satisfaction. In an adjusted analysis, the strongest predictors of discordance in patient-surgeon satisfaction were unmet patient expectations and the presence of complications. Advice to potential joint arthroplasty candidates regarding the decision to proceed with surgery should be informed by patient reported outcomes, rather than the surgeon's opinion of the likelihood of success.

  11. Sex therapy: an adjunct in the treatment of marital discord.

    Science.gov (United States)

    Mobarak, A; Tamerin, J S; Tamerin, N G

    1986-01-01

    This is a pilot project where sex therapy format was used in a group setting for the treatment of six married couples who had severe marital discord. None of the patients had a diagnosable sexual dysfunction, but sexual dissatisfaction was one of the common universal complaints. The article describes the treatment format and the clinical progress of the couples. In spite of the fact that the couples' marital discord has been refractory to prior therapy, there has been an overall improvement in their marriage as their sexuality improved. Possible therapeutic factors which led to this improvement are addressed. Despite limitations in patients' sampling and size, the results have been promising enough to encourage others to explore this modality as an alternative or adjunctive treatment for couples with severe marital discord and sexual dissatisfaction who have been refractory to unstructured traditional therapy.

  12. Gene Tree Discordance Causes Apparent Substitution Rate Variation.

    Science.gov (United States)

    Mendes, Fábio K; Hahn, Matthew W

    2016-07-01

    Substitution rates are known to be variable among genes, chromosomes, species, and lineages due to multifarious biological processes. Here, we consider another source of substitution rate variation due to a technical bias associated with gene tree discordance. Discordance has been found to be rampant in genome-wide data sets, often due to incomplete lineage sorting (ILS). This apparent substitution rate variation is caused when substitutions that occur on discordant gene trees are analyzed in the context of a single, fixed species tree. Such substitutions have to be resolved by proposing multiple substitutions on the species tree, and we therefore refer to this phenomenon as Substitutions Produced by ILS (SPILS). We use simulations to demonstrate that SPILS has a larger effect with increasing levels of ILS, and on trees with larger numbers of taxa. Specific branches of the species trees are consistently, but erroneously, inferred to be longer or shorter, and we show that these branches can be predicted based on discordant tree topologies. Moreover, we observe that fixing a species tree topology when performing tests of positive selection increases the false positive rate, particularly for genes whose discordant topologies are most affected by SPILS. Finally, we use data from multiple Drosophila species to show that SPILS can be detected in nature. Although the effects of SPILS are modest per gene, it has the potential to affect substitution rate variation whenever high levels of ILS are present, particularly in rapid radiations. The problems outlined here have implications for character mapping of any type of trait, and for any biological process that causes discordance. We discuss possible solutions to these problems, and areas in which they are likely to have caused faulty inferences of convergence and accelerated evolution.

  13. Quantification of quantum discord in a antiferromagnetic Heisenberg compound

    Energy Technology Data Exchange (ETDEWEB)

    Singh, H., E-mail: chiranjib@iiserkol.ac.in; Chakraborty, T., E-mail: chiranjib@iiserkol.ac.in; Mitra, C., E-mail: chiranjib@iiserkol.ac.in [Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur Campus, Mohanpur -741252, Nadia, West Bengal (India)

    2014-04-24

    An experimental quantification of concurrence and quantum discord from heat capacity (C{sub p}) measurement performed over a solid state system has been reported. In this work, thermodynamic measurements were performed on copper nitrate (CN, Cu(NO{sub 3}){sub 2}⋅2.5H{sub 2}O) single crystals which is an alternating antiferromagnet Heisenberg spin 1/2 system. CN being a weak dimerized antiferromagnet is an ideal system to investigate correlations between spins. The theoretical expressions were used to obtain concurrence and quantum discord curves as a function of temperature from heat capacity data of a real macroscopic system, CN.

  14. Entanglement and discord for qubits and higher spin systems

    Indian Academy of Sciences (India)

    A R P Rau

    2014-08-01

    We discuss aspects of entanglement and quantum discord, two of the quantum correlations that are of much interest in the field of quantum information. Their definitions and handling will be discussed, with simple illustrative examples. A specific example is of entanglement decay resulting from a simple dissipative process and how to alter that decay. An analytical prescription for computing quantum discord when a qubit (spin-1/2 or two-level quantum system) is involved is presented along with applications, and its generalization to higher spins (many levels) indicated.

  15. Amelia in Twin Pregnancy

    Directory of Open Access Journals (Sweden)

    Davari Tanha Fatemeh

    2009-04-01

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

  16. Identical Twins Raised Apart

    Science.gov (United States)

    Farnsworth, David L.

    2015-01-01

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

  17. 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.

  18. Twin Hub Network (poster)

    NARCIS (Netherlands)

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

    2014-01-01

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

  19. Mitral valve regurgitation in twins

    DEFF Research Database (Denmark)

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

    2016-01-01

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

  20. Methylation as an epigenetic source of random genetic effects in the classical twin design

    Directory of Open Access Journals (Sweden)

    Dolan CV

    2015-09-01

    Full Text Available Conor V Dolan,1,3 Michel G Nivard,1,3 Jenny van Dongen,1,3 Sophie van der Sluis,2 Dorret I Boomsma,1,3,41Department of Biological Psychology, Netherlands Twin Register, VU University Amsterdam, 2Section Complex Trait Genetics, Department of Clinical Genetics, VU Medical Center, 3EMGO+ Institute for Health and Care Research, VU University Medical Center, 4Neuroscience Campus Amsterdam, Amsterdam, the Netherlands Abstract: The epigenetic effects of cytosine methylation on gene expression are an acknowledged source of phenotypic variance. The discordant monozygotic (MZ twin design has been used to demonstrate the role of methylation in disease. Application of the classical twin design, featuring both monozygotic and dizygotic twins, has demonstrated that individual differences in methylation levels are attributable to genetic and environmental (including stochastic factors, with the latter explaining most of the variance. What implications epigenetic sources of variance have for the twin modeling of (non-epigenetic phenotypes such as height and IQ is an open question. One possibility is that epigenetic effects are absorbed by the variance component attributable to unshared environmental. Another possibility is that such effects form an independent source of variance distinguishable in principle from standard genetic and environmental sources. In the present paper, we conceptualized epigenetic processes as giving rise to randomness in the effects of polygenetic influences. This means that the regression coefficient in the regression of the phenotype on the polygenic factor, as specified in the twin model, varies over individuals. We investigate the consequences of ignoring this randomness in the standard twin model. Keywords: classical twin design, epigenetics, methylation, parameter randomness, heritability

  1. Thermal quantum discord in Heisenberg models with Dzyaloshinski-Moriya interaction

    Institute of Scientific and Technical Information of China (English)

    Wang Lin-Cheng; Yan Jun-Yan; Yi Xue-Xi

    2011-01-01

    We study the quantum discord of the bipartite Heisenberg model with the Dzyaloshinski-Moriya(DM)interaction in thermal equilibrium state and discuss the effect of the DM interaction on the quantum discord.The quantum entanglement of the system is also discussed and compared with quantum discord. Our results show that the quantum discord may reveal more properties of the system than quantum entanglement and the DM interaction may play an important role in the Heisenberg model.

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

    Science.gov (United States)

    Segal, Nancy L

    2016-06-01

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

  3. Molecular analysis of the gut microbiota of identical twins with Crohn's disease

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Janet; Dicksved, Johan; Halfvarson, Jonas; Rosenquist, Magnus; Jarnerot, Gunnar; Tysk, Curt; Apajalahti, Juha; Engstrand, Lars; Jansson, Janet K.

    2008-03-14

    Increasing evidence suggests that a combination of host genetics and the composition of the gut microbiota are important for development of Crohn's disease (CD). Our aim was to study identical twins with CD to determine microbial factors independently of host genetics. Fecal samples were studied from 10 monozygotic twin pairs with CD (discordant n=6, concordant n=4) and 8 healthy twin pairs. DNA was extracted, 16S rRNA genes were PCR amplified and T-RFLP fingerprints generated using general bacterial and Bacteroides group specific primers. The microbial communities were also profiled based on their % G+C contents. Bacteroides 16S rRNA genes were cloned and sequenced from a subset of the samples. The bacterial diversity in each sample and similarity indices between samples were estimated based on the T-RFLP data using a combination of statistical approaches. Healthy individuals had a significantly higher bacterial diversity compared to individuals with CD. The fecal microbial communities were more similar between healthy twins than between twins with CD, especially when these were discordant for the disease. The microbial community profiles of individuals with ileal CD were significantly different from healthy individuals and those with colonic CD. Also, CD individuals had a lower relative abundance of B. uniformis and higher relative abundances of B. ovatus and B. vulgatus. Our results suggest that genetics and/or environmental exposure during childhood in part determine the gut microbial composition. However, CD is associated with dramatic changes in the gut microbiota and this was particularly evident for individuals with ileal CD.

  4. The Roots of Autism and ADHD Twin Study in Sweden (RATSS).

    Science.gov (United States)

    Bölte, Sven; Willfors, Charlotte; Berggren, Steve; Norberg, Joakim; Poltrago, Lina; Mevel, Katell; Coco, Christina; Fransson, Peter; Borg, Jacqueline; Sitnikov, Rouslan; Toro, Roberto; Tammimies, Kristiina; Anderlid, Britt-Marie; Nordgren, Ann; Falk, Anna; Meyer, Urs; Kere, Juha; Landén, Mikael; Dalman, Christina; Ronald, Angelica; Anckarsäter, Henrik; Lichtenstein, Paul

    2014-06-01

    Neurodevelopmental disorders affect a substantial minority of the general population. Their origins are still largely unknown, but a complex interplay of genetic and environmental factors causing disturbances of the central nervous system's maturation and a variety of higher cognitive skills is presumed. Only limited research of rather small sample size and narrow scope has been conducted in neurodevelopmental disorders using a twin-differences design. The Roots of Autism and ADHD Twin Study in Sweden (RATSS) is an ongoing project targeting monozygotic twins discordant for categorical or dimensional autistic and inattentive/hyperactive-impulsive phenotypes as well as other neurodevelopmental disorders, and typically developing twin controls. Included pairs are 9 years of age or older, and comprehensively assessed for psychopathology, medical history, neuropsychology, and dysmorphology, as well as structural, functional, and molecular brain imaging. Specimens are collected for induced pluripotent (iPS) and neuroepithelial stem cells, genetic, gut bacteria, protein-/monoamine, and electron microscopy analyses. RATSS's objective is to generate a launch pad for novel surveys to understand the complexity of genotype-environment-phenotype interactions in autism spectrum disorder and attention-deficit hyperactivity disorder (ADHD). By October 2013, RATSS had collected data from 55 twin pairs, among them 10 monozygotic pairs discordant for autism spectrum disorder, seven for ADHD, and four for other neurodevelopmental disorders. This article describes the design, recruitment, data collection, measures, collected pairs' characteristics, as well as ongoing and planned analyses in RATSS. Potential gains of the study comprise the identification of environmentally mediated biomarkers, the emergence of candidates for drug development, translational modeling, and new leads for prevention of incapacitating outcomes.

  5. Spatial patterns in discordant diagnostic test results for Chagas disease: links to transmission hotspots.

    Science.gov (United States)

    Levy, Michael Z; Bowman, Natalie M; Kawai, Vivian; Plotkin, Joshua B; Waller, Lance A; Cabrera, Lilia; Steurer, Frank; Seitz, Amy E; Pinedo-Cancino, Viviana V; Cornejo del Carpio, Juan Geny; Cordova Benzaquen, Eleazar; McKenzie, F Ellis; Maguire, James H; Gilman, Robert H; Bern, Caryn

    2009-04-15

    Diagnosis of Chagas disease is hindered by discordance between screening and confirmatory test results for Trypanosoma cruzi infection. In periurban Arequipa, Peru, spatial analysis revealed that individuals with discordant test results are spatially clustered in hotspots of T. cruzi transmission, suggesting that discordant results likely represent true infections in this setting.

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

    NARCIS (Netherlands)

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

    2009-01-01

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

  7. Co-twin study of the effect of environment and dietary elements on acquisition of Helicobacter pylori infection.

    Science.gov (United States)

    Malaty, H M; Graham, D Y; Isaksson, I; Engstrand, L; Pedersen, N L

    1998-10-15

    The rate of Helicobacter pylori infection is inversely related to socioeconomic status, and childhood is thought to be the major acquisition period. The authors investigated the importance of childhood environment in the acquisition of H. pylori infection. A cross-sectional study was conducted of monozygotic and dizygotic twins who were reared apart or reared together. Three hundred twins from a subregistry of the Swedish Twin Registry were studied. H. pylori status was evaluated by using an enzyme-linked immunosorbent assay for anti-H. pylori immunoglobulin G. Socioeconomic status during childhood was assessed on the basis of the density of the living conditions and the economic situation of the family that reared the twins. Current socioeconomic status was estimated by using a scale that combined income and education. Dietary elements that were studied included fat and fiber intake and ascorbic acid consumption. The density of the childhood home was consistently found to be significantly associated with the acquisition of H. pylori infection (p = 0.04). Among monozygotic twins reared apart and discordant for H. pylori status, affected twins were raised in homes under poorer socioeconomic conditions than those of their unaffected co-twins (p = 0.02). Additionally, infected twins consumed more ascorbic acid than their unaffected co-twins (p = 0.04). The finding of an effect of socioeconomic status during childhood on the acquisition of H. pylori among monozygotic twins who were reared apart and had an identical genetic makeup but not a common environment confirms the hypothesis that childhood acquisition of H. pylori infection is linked to hygiene practices.

  8. Marital Discord and Marital Separation: A County Survey.

    Science.gov (United States)

    Kitson, Gay C.

    1985-01-01

    Explored the frequency of marital separations of 48 hours or more due to marital discord in Cuyahoga County, Ohio, residents (N=1,101). Results indicated one in six couples is likely to separate at some point in their relationship. Income and children account for much of the variation between race, sex, and separations. (Author/BL)

  9. Revised Definitions of Quantum Dissonance and Quantum Discord

    CERN Document Server

    Zhang, Zhan-jun

    2010-01-01

    We show that all the correlations defined by K. Modi et al [Phys. Rev. Lett. {\\bf 104}, 080501 (2010)] except for the total mutual information should be redefined so that some physical quantities (e.g., the accessible maximal classical correlation and the resultant exact quantum discord) are right.

  10. Lung cancer, genetic predisposition and smoking: the Nordic Twin Study of Cancer

    DEFF Research Database (Denmark)

    Hjelmborg, Jacob v. B.; Korhonen, Tellervo; Holst, Klaus;

    2016-01-01

    Background: We aimed to disentangle genetic and environmental causes in lung cancer while considering smoking status. Methods: Four Nordic twin cohorts (43 512 monozygotic (MZ) and 71 895 same sex dizygotic (DZ) twin individuals) had smoking data before cancer diagnosis. We used time...... for lung cancer, nearly all were current smokers at baseline and only one concordant pair was seen among never smokers. Among ever smokers, the case-wise concordance of lung cancer, that is the risk before a certain age conditional on lung cancer in the co-twin before that age, was significantly increased...... pairs. Among smoking discordant pairs, the pairwise HR for lung cancer of the ever smoker twin compared to the never smoker co-twin was 5.4 (95% CI 2.1 to 14.0) in MZ pairs and 5.0 (95% CI 3.2 to 7.9) in DZ pairs. Conclusions: The contribution of familial effects appears to decrease by age...

  11. Relationship between type 1 diabetes and atopic diseases in a twin population

    DEFF Research Database (Denmark)

    Thomsen, S F; Duffy, D L; Kyvik, K O;

    2011-01-01

    AIM: To study the association between type 1 diabetes and atopic diseases in a twin population. METHODS: We performed record linkage between questionnaire-defined atopic dermatitis, asthma and hay fever, and hospital discharge diagnoses of type 1 diabetes in 54,530 Danish twins, 3-71 years of age....... RESULTS: The age- and sex-adjusted risk of atopic dermatitis was decreased in subjects with type 1 diabetes compared with nondiabetic subjects, (2.1%vs 9.9%), odds ratio (OR)= 0.23 (0.07-0.71), P = 0.011, whereas asthma and hay fever were not significantly associated with type 1 diabetes. Within twin...... pairs discordant for type 1 diabetes, the diabetic twin had a lower risk of atopic dermatitis relative to the nondiabetic co-twin. Genetic factors for atopic dermatitis and type 1 diabetes were negatively correlated (r = -0.30), P = 0.0009. CONCLUSIONS: These findings substantiate the Th1 vs Th2 cell...

  12. Monozygotic twins with Neurofibromatosis type 1, concordant phenotype and synchronous development of MPNST and metastasis

    Directory of Open Access Journals (Sweden)

    Melean German

    2010-08-01

    Full Text Available Abstract Background Neurofibromatosis type 1 is a common autosomal dominant disorder with full penetrance and variable expression. The condition predisposes individuals to the development of malignant nervous system tumours, most frequently Malignant Peripheral Nerve Sheath Tumours (MPNSTs. Previous studies indicate that genetic factors other than mutations in NF1 may be responsible for the condition's variable expression. Case report Here we present data from a pair of monozygotic twins affected by Neurofibromatosis type 1 resulting from a de novo mutation. Both twins developed a left sciatic plexiform neurofibroma that evolved into MPNST at a similar age and they also developed pulmonary metastasis at the same age. Other concordant traits between the twins were: macrocephaly, psychomotor delay, café-au-lait spots, cutaneous neurofibromas, retroperitoneal, pleural and paraspinal neurofibromas. The main discordant features observed were tibial pseudoarthrosis, pectus carinatum, osteoporosis and thymus hyperplasia. Conclusions This is the first report of monozygotic twins with Neurofibromatosis type 1 that develop MPNSTs, the localization and chronological evolution of which, and its metastasis, is concordant in both twins. These cases suggest that the events involved in the transformation of benign plexiform neurofibromas to MPNSTs in Neurofibromatosis type 1, follow a spatiotemporally programme that is influenced by heritable factors other than NF1 mutations.

  13. Social activity and healthy aging: a study of aging Danish twins.

    Science.gov (United States)

    McGue, Matt; Christensen, Kaare

    2007-04-01

    Although social and intellectual engagement have been consistently associated with late-life functioning, rather than true causation, these associations may reflect the experiential choices of high functioning individuals (i.e., selection effects). We investigated the association of social activity with late-life physical functioning, cognitive functioning, and depression symptomatology using data from 1112 pairs of like-sex twins who participated in the Longitudinal Study of Aging Danish Twins. Consistent with previous research, we found that social activity was significantly correlated with overall level of physical functioning, cognitive functioning, and depression symptomatology. We also found that social activity was significantly and moderately heritable (estimate of .36), raising the possibility that its association with late-life functioning might reflect selection processes. Further, social activity did not predict change in functioning and in monozygotic twin pairs discordant on level of social activity, the more socially active twin was not less susceptible to age decreases in physical and cognitive functioning and increases in depression symptomatology than the less socially active twin. These results are interpreted in the context of the additional finding that nonshared environmental factors, although apparently not social activity, are the predominant determinant of changes in late-life functioning.

  14. 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.

  15. Quantum Discord Dynamics in Two Different Non-Markovian Reservoirs

    Institute of Scientific and Technical Information of China (English)

    DING Bang-Fu; WANG Xiao-Yun; LIU Jing-Feng; YAN Lin; ZHAO He-Ping

    2011-01-01

    The quantum discord dynamics of two non-coupled two-level atoms independently interacting with their reservoir is studied under two kinds of non-Markovian conditions,namely,an off-resonant case with atomic transition frequency and a photonic band gap.In the first case,the phenomenon of the quantum discord loss and the oscillatory behavior of the quantum discord can occur by changing the detuning quantity and reducing the spectral coupling width for any initial Bell state.Under the second condition,the trapping phenomenon of the quantum discord can be presented by adjusting the width of gap,that is,the quantum discord of two atoms keep a nonzero constant for a long time.Entanglement,as a kind of quantum correlation without a classical counterpart,plays an important role in quantum information and communication theory,[1,2] quantum teleportation,[3] quantum cryptography[4,5] and universal quantum computing.[6]%We report the first implementation of transparent electrodes in bottom-gate graphene transistors used for photo detection. Compared to conventional nontransparent electrodes, the transparent electrodes allow photons to transmit through to the graphene beneath, providing an enlarged absorption area and thereby giving rise to an enhancement of photocurrent generation. The devices are fabricated with an asymmetric metallization scheme and the experimental results show that the maximum photocurrent density using the transparent electrodes (ITO and Pd/ITO) is over two times higher than that using the nontransparent electrodes (Ti and Pd), indicating a significant enhancement in the performance of graphene photo sensors.

  16. Minimal Mirror Twin Higgs

    CERN Document Server

    Barbieri, Riccardo; Harigaya, Keisuke

    2016-01-01

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

  17. Nutrition in twin pregnancy.

    Science.gov (United States)

    MacGillivray, I

    1979-01-01

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

  18. Emergence of Digital Twins

    OpenAIRE

    Datta, Shoumen Palit Austin

    2016-01-01

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

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

    Science.gov (United States)

    Segal, Nancy L

    2014-10-01

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

  20. Trojan twin planets

    Science.gov (United States)

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

    2017-03-01

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

  1. Twin studies of schizophrenia: from bow-and-arrow concordances to star wars Mx and functional genomics.

    Science.gov (United States)

    Cardno, A G; Gottesman, I I

    2000-01-01

    Twin studies have been vital for establishing an important genetic contribution to the etiology of schizophrenia. The five newest studies since 1995 from Europe and Japan have confirmed earlier findings. They yielded probandwise concordance rates of 41-65% in monozygotic (MZ) pairs and 0-28% in dizygotic (DZ) pairs, and heritability estimates of approximately 80-85%. Twin studies are also valuable for investigating the etiological relationships between schizophrenia and other disorders, and the genetic basis of clinical heterogeneity within schizophrenia. Studies of discordant MZ pairs provide further insights into non-inherited factors that contribute to the multifactorial etiology of this disorder. More recently, twin studies have begun to be used to directly investigate molecular genetic and epigenetic processes underlying schizophrenia.

  2. Impact of the Xba1-polymorphism of the human muscle glycogen synthase gene on parameters of the insulin resistance syndrome in a Danish twin population

    DEFF Research Database (Denmark)

    Fenger, M; Poulsen, P; Beck-Nielsen, H;

    2000-01-01

    was increased in female carriers of the A2-allele with impaired glucose tolerance or Type 2 diabetes mellitus (79 +/- 1 vs. 94 +/- 4 mmHg, P insulin resistance syndrome were associated with the polymorphism. CONCLUSIONS......AIMS: To establish the impact on the insulin resistance syndrome of the intron 14 Xba1-polymorphism in human muscle glycogen synthase (GYS1). METHODS: Parameters related to the insulin resistance syndrome were measured in 244 monozygotic twins and 322 dizygotic twins with or without impaired...... and the remainder had the genotype A1A2. No A2A2-genotypes were detected. In 11 genotypic discordant dizygotic twin pairs the insulin resistance was significantly increased in the twins carrying the A1A2 genotype regardless of sex (HOMA index 1.81 (A1A1) vs. 2.57 (A1A2), P

  3. Impact of the Xba1-polymorphism of the human muscle glycogen synthase gene on parameters of the insulin resistance syndrome in a Danish twin population

    DEFF Research Database (Denmark)

    Fenger, M; Poulsen, P; Beck-Nielsen, H;

    2000-01-01

    : The Xba1-polymorphism of the human muscle glycogen synthase gene is correlated to insulin resistance and to diastolic blood pressure. The polymorphism does not involve any known transcription factor or any structural change in GYS1, and these correlations are therefore most probably caused by linkage......AIMS: To establish the impact on the insulin resistance syndrome of the intron 14 Xba1-polymorphism in human muscle glycogen synthase (GYS1). METHODS: Parameters related to the insulin resistance syndrome were measured in 244 monozygotic twins and 322 dizygotic twins with or without impaired...... and the remainder had the genotype A1A2. No A2A2-genotypes were detected. In 11 genotypic discordant dizygotic twin pairs the insulin resistance was significantly increased in the twins carrying the A1A2 genotype regardless of sex (HOMA index 1.81 (A1A1) vs. 2.57 (A1A2), P

  4. A Comparison of the Attempts of Quantum Discord and Quantum Entanglement to Capture Quantum Correlations

    CERN Document Server

    Al-Qasimi, Asma

    2010-01-01

    Measurements of Quantum Systems disturb their states. To quantify this non-classical characteristic, Zurek and Ollivier introduced the quantum discord, a quantum correlation which can be nonzero even when entanglement in the system is zero. Discord has aroused great interest as a resource that is more robust against the effects of decoherence and offers exponential speed up of certain computational algorithms. Here, we study general two-level bipartite systems and give general results on the relationship between discord, entanglement, and linear entropy, and identify the states for which discord takes a maximal value for a given entropy or entanglement, thus placing strong bounds on entanglement-discord and entropy-discord relations. We find out that although discord and entanglement are identical for pure states, they differ when generalized to mixed states as a result of the difference in the method of generalization.

  5. When You Are a Twin or Triplet

    Science.gov (United States)

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

  6. Twinning across the Developing World.

    Directory of Open Access Journals (Sweden)

    Jeroen Smits

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

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

    Science.gov (United States)

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

    2006-05-01

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

  8. Estimating twin concordance for bivariate competing risks twin data

    DEFF Research Database (Denmark)

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

    2014-01-01

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

  9. The Impact of the in utero and Early Postnatal Environments on Grey and White Matter Volume: A Study with Adolescent Monozygotic Twins.

    Science.gov (United States)

    Levesque, Melissa L; Fahim, Cherine; Ismaylova, Elmira; Verner, Marie-Pier; Casey, Kevin F; Vitaro, Frank; Brendgen, Mara; Dionne, Ginette; Boivin, Michel; Tremblay, Richard E; Booij, Linda

    2015-01-01

    Prenatal and early postnatal adversities have been shown to be associated with brain development. However, we do not know how much of this association is confounded by genetics, nor whether the postnatal environment can moderate the impact of in utero adversity. This study used a monozygotic (MZ) twin design to assess (1) the association between birth weight (BW) and brain volume in adolescence, (2) the association between within-twin-pair BW discordance and brain volume discordance in adolescence, and (3) whether the association between BW and brain volume in adolescence is mediated or moderated by early negative maternal parenting behaviours. These associations were assessed in a sample of 108 MZ twins followed longitudinally since birth and scanned at age 15. The total grey matter (GM) and white matter (WM) volumes were obtained using the Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL) toolbox in the Statistical Parametric Mapping version 8 (SPM8). We found that the BW was significantly associated with the total GM and WM volumes, particularly in the superior frontal gyrus and thalamus. Within-twin-pair discordance in BW was also significantly associated with within-pair discordance in both the GM and the WM volumes, supporting the hypothesis that the specific in utero environment is associated with brain development independently of genetics. Early maternal hostile parenting behaviours and depressive symptoms were associated with total GM volume but not WM volume. Finally, greater early maternal hostility may moderate the association between the BW and GM volume in adolescence, since the positive association between the BW and total GM volume appeared stronger at higher levels of maternal hostility (trend). Together, these findings support the importance of the in utero and early environments for brain development.

  10. Probing quantum discord in a Heisenberg dimer compound.

    Science.gov (United States)

    Chakraborty, Tanmoy; Singh, Harkirat; Singh, Sourabh; Gopal, Radha Krishna; Mitra, Chiranjib

    2013-10-23

    A quantitative estimation of quantum discord is performed for a Heisenberg spin 1/2 dimer compound (NH4CuPO4, H2O) by means of experimental magnetic and thermal measurements. Magnetic susceptibility and specific heat data were collected for NH4CuPO4, H2O and analyzed within the framework of the Heisenberg isolated dimer model. Internal energy as a function of temperature is obtained by integrating the specific heat versus temperature data. Subsequently, quantum discord, total correlations and spin-spin correlation function are quantified from susceptibility and internal energy and plotted as a function of temperature. Violation of Bell's inequality is also tested for NH4CuPO4, H2O via both experimental susceptibility and specific heat data signifying the presence of entanglement.

  11. Parameter-Free Search of Time-Series Discord

    Institute of Scientific and Technical Information of China (English)

    Wei Luo; Marcus Gallagher; Janet Wiles

    2013-01-01

    Time-series discord is widely used in data mining applications to characterize anomalous subsequences in time series.Compared to some other discord search algorithms,the direct search algorithm based on the recurrence plot shows the advantage of being fast and parameter free.The direct search algorithm,however,relies on quasi-periodicity in input time series,an assumption that limits the algorithm's applicability.In this paper,we eliminate the periodicity assumption from the direct search algorithm by proposing a reference function for subsequences and a new sampling strategy based on the reference function.These measures result in a new algorithm with improved efficiency and robustness,as evidenced by our empirical evaluation.

  12. Entanglement and discord assisted entropic uncertainty relations under decoherence

    Science.gov (United States)

    Yao, ChunMei; Chen, ZhiHua; Ma, ZhiHao; Severini, Simone; Serafini, Alessio

    2014-09-01

    The uncertainty principle is a crucial aspect of quantum mechanics. It has been shown that quantum entanglement as well as more general notions of correlations, such as quantum discord, can relax or tighten the entropic uncertainty relation in the presence of an ancillary system. We explored the behaviour of entropic uncertainty relations for system of two qubits-one of which subjects to several forms of independent quantum noise, in both Markovian and non-Markovian regimes. The uncertainties and their lower bounds, identified by the entropic uncertainty relations, increase under independent local unital Markovian noisy channels, but they may decrease under non-unital channels. The behaviour of the uncertainties (and lower bounds) exhibit periodical oscillations due to correlation dynamics under independent non-Markovian reservoirs. In addition, we compare different entropic uncertainty relations in several special cases and find that discord-tightened entropic uncertainty relations offer in general a better estimate of the uncertainties in play.

  13. Markovian Classicality from Zero Discord for Bipartite Quantum Systems

    CERN Document Server

    Arsenijevic, M; Dugic, M

    2012-01-01

    Modern quantum information theory provides new tools for investigating the decoherence-induced "classicality" of open quantum systems. Recent observation that almost all quantum states bear non-classical correlations [A. Ferraro {\\it et al}, Phys. Rev. A {\\bf 81}, 052318 (2010)] distinguishes the zero-discord classicality essentially as a pathology of the Markovian bipartite-systems realm. Nevertheless, we formally construct such a classical model and its variant that represents a matter-of-principle formal proof, i.e. a sufficient condition for the, otherwise not obvious, existence of the Markovian zero-discord classicality. A need for the more elaborate and more systematic search for the alternative such models reveals we are still learning about the very meaning of "classicality" in the realm of open quantum systems.

  14. Markovian Zero-Discord Classicality for Bipartite Quantum Systems

    CERN Document Server

    Arsenijevic, M; Dugic, M

    2012-01-01

    Recent observation that almost all quantum states bear nonclassical correlations [A. Ferraro et al, Phys. Rev. A 81, 052318 (2010)] distinguishes the zero-discord classicality essentially as a rareness of the Markovian bipartite systems realm. This seems to be in contrast with decoherence-theory established classicality where classical states are robust and unavoidable. Nevertheless, we formally construct such a classical model and its variant that represents a matter-of-principle formal proof, i.e. a sufficient condition for the, otherwise not obvious, existence of the Markovian zero-discord classicality. Rigorous analysis suggests there is no alternative to classical model, aside approximate model which follows from relaxing rigid quantum information constraints on classical model. A need for the more elaborate and more systematic search for the alternative such models (if there any) reveals we are still learning about the very meaning of "classicality" in the realm of open quantum systems.

  15. General monogamy property of global quantum discord and the application

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Si-Yuan [Institute of Modern Physics, Northwest University, Xian 710069 (China); Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Zhang, Yu-Ran, E-mail: yrzhang@iphy.ac.cn [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Zhao, Li-Ming [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Yang, Wen-Li, E-mail: wlyang@nwu.edu.cn [Institute of Modern Physics, Northwest University, Xian 710069 (China); Fan, Heng, E-mail: hfan@iphy.ac.cn [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Collaborative Innovation Center of Quantum Matter, Beijing (China)

    2014-09-15

    We provide a family of general monogamy inequalities for global quantum discord (GQD), which can be considered as an extension of the usual discord monogamy inequality. It can be shown that those inequalities are satisfied under the similar condition for the holding of usual monogamy relation. We find that there is an intrinsic connection among them. Furthermore, we present a different type of monogamy inequality and prove that it holds under the condition that the bipartite GQDs do not increase when tracing out some subsystems. We also study the residual GQD based on the second type of monogamy inequality. As applications of those quantities, we investigate the GQDs and residual GQD in characterizing the quantum phase transition in the transverse field Ising model.

  16. MULTIPLE CRITERIA DECISION MAKING:DISCORDANT PREFERENCES AND PROBLEM DESCRIPTION

    Institute of Scientific and Technical Information of China (English)

    Alexey B.PETROVSKY

    2007-01-01

    There are many practical decision problems where decision makers' preferences may be inconsistent and contradictory.In this paper,new methods for ordering and classifying multi-attribute objects by discordant collective preferences are suggested.These methods are based on the theory of multiset metric spaces.The proposed techniques are applied to ranking companies and a competitive selection of projects,which are estimated by several experts upon multiple qualitative criteria.

  17. Evolution of the Australian-Antarctic discordance since Miocene time

    OpenAIRE

    Marks, Karen M.; Stock, Joann M.; Quinn, Katherine J.

    1999-01-01

    In this study we chronicle the development of the Australian-Antarctic discordance (AAD), the crenelated portion of the Southeast Indian Ridge between ∼120° and 128°E, since anomaly 6y time (19 Ma). We reconstruct satellite-derived marine gravity fields and depth anomalies at selected times by first removing anomalies overlying seafloor younger than the selected age, and then rotating the remaining anomalies through improved finite rotations based on a very detailed set of magnetic anomaly id...

  18. Direct scheme for measuring the geometric quantum discord

    CERN Document Server

    Jin, Jia-sen; Yu, Chang-shui; Song, He-shan

    2011-01-01

    We propose a scheme to directly measure the exact value of geometric quantum discord of an arbitrary two-qubit state. We only need to perform the projective measurement in the all anti-symmetric subspace and our scheme is parametrically efficient in contrast to the widely adopted quantum state tomography scheme in the sense of less parameter estimations and projectors. Moreover, the present scheme can be easily realized with the current experimental techniques.

  19. Confronting Twin Paradox Acceleration

    Science.gov (United States)

    Murphy, Thomas W.

    2016-05-01

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

  20. Holographic twin Higgs model.

    Science.gov (United States)

    Geller, Michael; Telem, Ofri

    2015-05-15

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

  1. Visual Bias Predicts Gait Adaptability in Novel Sensory Discordant Conditions

    Science.gov (United States)

    Brady, Rachel A.; Batson, Crystal D.; Peters, Brian T.; Mulavara, Ajitkumar P.; Bloomberg, Jacob J.

    2010-01-01

    We designed a gait training study that presented combinations of visual flow and support-surface manipulations to investigate the response of healthy adults to novel discordant sensorimotor conditions. We aimed to determine whether a relationship existed between subjects visual dependence and their postural stability and cognitive performance in a new discordant environment presented at the conclusion of training (Transfer Test). Our training system comprised a treadmill placed on a motion base facing a virtual visual scene that provided a variety of sensory challenges. Ten healthy adults completed 3 training sessions during which they walked on a treadmill at 1.1 m/s while receiving discordant support-surface and visual manipulations. At the first visit, in an analysis of normalized torso translation measured in a scene-movement-only condition, 3 of 10 subjects were classified as visually dependent. During the Transfer Test, all participants received a 2-minute novel exposure. In a combined measure of stride frequency and reaction time, the non-visually dependent subjects showed improved adaptation on the Transfer Test compared to their visually dependent counterparts. This finding suggests that individual differences in the ability to adapt to new sensorimotor conditions may be explained by individuals innate sensory biases. An accurate preflight assessment of crewmembers biases for visual dependence could be used to predict their propensities to adapt to novel sensory conditions. It may also facilitate the development of customized training regimens that could expedite adaptation to alternate gravitational environments.

  2. Transformation: From Twin to Individual

    Science.gov (United States)

    Magagna, Jeanne

    2007-01-01

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

  3. Hypertensive disorders in twin pregnancy

    NARCIS (Netherlands)

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

    1995-01-01

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

  4. Twin Studies of Atopic Dermatitis

    DEFF Research Database (Denmark)

    Elmose, Camilla; Thomsen, Simon Francis

    2015-01-01

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

  5. Twin Higgs WIMP Dark Matter

    CERN Document Server

    García, Isabel García; March-Russell, John

    2015-01-01

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

  6. 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.

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

    Science.gov (United States)

    Segal, Nancy L

    2008-10-01

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

  8. [Hereditary phaeochromocytoma in twins].

    Science.gov (United States)

    Tóth, Géza; Patócs, Attila; Tóth, Miklós

    2016-08-01

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

  9. 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…

  10. Recipient twin limb ischemia with postnatal onset.

    Science.gov (United States)

    Broadbent, Roland Spencer

    2007-02-01

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

  11. Best Practices for Twin Placement in School

    Science.gov (United States)

    Lacina, Jan

    2012-01-01

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

  12. Paternal age and telomere length in twins

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  13. Twin Higgs Asymmetric Dark Matter.

    Science.gov (United States)

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

    2015-09-18

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

  14. The vector-like twin Higgs

    Science.gov (United States)

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

    2016-07-01

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

  15. The Vector-like Twin Higgs

    CERN Document Server

    Craig, Nathaniel; Longhi, Pietro; Strassler, Matthew

    2016-01-01

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

  16. Fivefold twinned boron carbide nanowires.

    Science.gov (United States)

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

    2009-09-01

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

  17. Failure of vincristine induce twinning

    Science.gov (United States)

    Binder, M.

    1984-01-01

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

  18. Geometric measure of quantum discord for an arbitrary state of a bipartite quantum system

    CERN Document Server

    Hassan, Ali Saif M; Joag, Pramod S

    2010-01-01

    Quantum discord, as introduced by Olliver and Zurek [Phys. Rev. Lett. \\textbf{88}, 017901 (2001)], is a measure of the discrepancy between quantum versions of two classically equivalent expressions for mutual information. Dakic, Vedral, and Brukner [arXiv:1004.0190 (2010)] introduced a geometric measure of quantum discord and derived an explicit formula for any two-qubit state. Luo and Fu [Phys. Rev. A \\textbf{82}, 034302 (2010)] introduced another form for geometric measure of quantum discord. We find an exact formula for the geometric measure of quantum discord for an arbitrary state of a $m\\times n$ bipartite quantum system.

  19. Prevalence of discordant microscopic changes with automated CBC analysis

    Directory of Open Access Journals (Sweden)

    Fabiano de Jesus Santos

    2014-12-01

    Full Text Available Introduction:The most common cause of diagnostic error is related to errors in laboratory tests as well as errors of results interpretation. In order to reduce them, the laboratory currently has modern equipment which provides accurate and reliable results. The development of automation has revolutionized the laboratory procedures in Brazil and worldwide.Objective:To determine the prevalence of microscopic changes present in blood slides concordant and discordant with results obtained using fully automated procedures.Materials and method:From January to July 2013, 1,000 hematological parameters slides were analyzed. Automated analysis was performed on last generation equipment, which methodology is based on electrical impedance, and is able to quantify all the figurative elements of the blood in a universe of 22 parameters. The microscopy was performed by two experts in microscopy simultaneously.Results:The data showed that only 42.70% were concordant, comparing with 57.30% discordant. The main findings among discordant were: Changes in red blood cells 43.70% (n = 250, white blood cells 38.46% (n = 220, and number of platelet 17.80% (n = 102.Discussion:The data show that some results are not consistent with clinical or physiological state of an individual, and cannot be explained because they have not been investigated, which may compromise the final diagnosis.Conclusion:It was observed that it is of fundamental importance that the microscopy qualitative analysis must be performed in parallel with automated analysis in order to obtain reliable results, causing a positive impact on the prevention, diagnosis, prognosis, and therapeutic follow-up.

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

    NARCIS (Netherlands)

    Lopriore, Enrico

    2006-01-01

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

  1. Thermal quantum discord in the Heisenberg chain with impurity

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Jia-Min, E-mail: jmgong@yeah.net; Hui, Zhan-Qiang

    2014-07-01

    We study thermal quantum discord (TQD) in the Heisenberg chain with spin site or magnetic impurity. The former one of which may induce inhomogeneous exchange interactions between the neighboring spins, while the latter one may model a spin chain with nonuniform magnetic field. In contrast to one's traditional understanding, we found that the spin impurity can be used to enhance the TQD greatly for all the bipartition schemes of the chain, while the magnetic impurity located on one spin can make the TQD between the other two spins approaching its maximum 1 for the antiferromagnetic chain.

  2. Quantum discord as a resource for quantum cryptography.

    Science.gov (United States)

    Pirandola, Stefano

    2014-11-07

    Quantum discord is the minimal bipartite resource which is needed for a secure quantum key distribution, being a cryptographic primitive equivalent to non-orthogonality. Its role becomes crucial in device-dependent quantum cryptography, where the presence of preparation and detection noise (inaccessible to all parties) may be so strong to prevent the distribution and distillation of entanglement. The necessity of entanglement is re-affirmed in the stronger scenario of device-independent quantum cryptography, where all sources of noise are ascribed to the eavesdropper.

  3. Simultaneous Intussusception in Monozygotic Twins

    Directory of Open Access Journals (Sweden)

    Mete Kaya

    2014-12-01

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

  4. Hypertensive disorders in twin pregnancy

    OpenAIRE

    Santema, Job; Koppelaar, Elin; Wallenburg, Henk

    1995-01-01

    textabstractObjective: To compare the incidence and severity of pregnancy-induced hypertensive disorders in twin pregnancy and in singleton gestation. Study design: Case-control study in the setting of a University Hospital. Each pregnancy of a consecutive series of 187 twin pregnancies attending the antenatal clinic and booked before a gestational age of 24 weeks was matched for maternal age, parity, and gestational age at delivery with a singleton pregnancy delivered in the same year. Prima...

  5. The Danish political twin study

    DEFF Research Database (Denmark)

    Klemmensen, Robert; Hobolt, Sara B; Dinesen, Peter Thisted

    2012-01-01

    We compare a recent Danish twin survey on political attitudes and behaviors to a nationally representative survey covering similar topics. We find very similar means and variances for most of our constructed scales of political attitudes and behaviors in the two surveys, although even small...... differences tend to be statistically significant due to sample size. This suggests that the twin study can be used to make inferences on the heritability of several political traits in the Danish population....

  6. Aragonite twinning in gastropod nacre

    Science.gov (United States)

    Mukai, Hiroki; Saruwatari, Kazuko; Nagasawa, Hiromichi; Kogure, Toshihiro

    2010-10-01

    Aragonite twinning in gastropod nacre has been investigated using scanning electron microscopy (SEM), electron back-scattered diffraction (EBSD), and transmission electron microscopy (TEM) with the focused ion beam (FIB) sample preparation technique. At the growth front of nacre, Haliotis discus hannai and Omphalius rusticus form a "stack-of-coins" structures, which consist of pseudo-hexagonal and elliptical aragonite tablets, respectively. SEM, EBSD, and TEM analyses revealed that these tablets are monolithic single crystal and almost free of the {1 1 0} twins that are common in aragonite of biotic or abiotic origin. The longest diagonal of the hexagon and the longer axis of the ellipse are parallel to the a-axis of aragonite. The crystal orientation of each tablet in a stack, measured by TEM-Kikuchi pattern analysis, is almost the same but there is occasionally {1 1 0} twin-like relationship between adjacent tablets along the stacking. On the other hand, the fibrous aragonite layer formed prior to the nacreous structure is composed of polycrystalline aragonite with high density of {1 1 0} twins. TEM observation suggests that the interlamellar organic sheet prevents the inheritance of the twins, by selecting only single domain of the twins, through the mineral bridge.

  7. The Qingdao Twin Registry: a status update.

    Science.gov (United States)

    Duan, Haiping; Ning, Feng; Zhang, Dongfeng; Wang, Shaojie; Zhang, Dong; Tan, Qihua; Tian, Xiaocao; Pang, Zengchang

    2013-02-01

    In 1998, the Qingdao Twin Registry was initiated as the main part of the Chinese National Twin Registry. By 2005, a total of 10,655 twin pairs had been recruited. Since then new twin cohorts have been sampled, with one longitudinal cohort of adolescent twins selected to explore determinants of metabolic disorders and health behaviors during puberty and young adulthood. Adult twins have been sampled for studying heritability of multiple phenotypes associated with metabolic disorders. In addition, an elderly twin cohort has been recruited with a focus on genetic studies of aging-related phenotypes using twin modeling and genome-wide association analysis. Cross-cultural collaborative studies have been carried out between China, Denmark, Finland, and US cohorts. Ongoing data collection and analysis for the Qingdao Twin Registry will be discussed in this article.

  8. A Generalized Geometric Measurement of Quantum Discord: Exact Treatment

    Science.gov (United States)

    Cui, Hai-Tao; Tian, Jun-Long; Yang, Gui

    2016-02-01

    A generalization of the geometric measure of quantum discord is introduced in this article, based on Hellinger distance. Our definition has virtues of computability and independence of local measurement. In addition it also does not suffer from the recently raised critiques about quantum discord. The exact result can be obtained for bipartite pure states with arbitrary levels, which is completely determined by the Schmidt decomposition. For bipartite mixed states the exact result can also be found for a special case. Furthermore the generalization into multipartite case is direct. It is shown that it can be evaluated exactly when the measured state is invariant under permutation or translation. In addition the detection of quantum phase transition is also discussed for Lipkin-Meshkov-Glick and Dicke model. Supported by National Natural Science Foundation of China under Grant No. 11005002 and 11475004, New Century Excellent Talent of M.O.E (NCET-11-0937), and Sponsoring Program of Excellent Younger Teachers in universities in Henan Province under Grant No. 2010GGJS-181

  9. Childhood trauma and personality disorder criterion counts: a co-twin control analysis.

    Science.gov (United States)

    Berenz, Erin C; Amstadter, Ananda B; Aggen, Steven H; Knudsen, Gun Peggy; Reichborn-Kjennerud, Ted; Gardner, Charles O; Kendler, Kenneth S

    2013-11-01

    Correlational studies consistently report relationships between childhood trauma (CT) and most personality disorder (PD) criteria and diagnoses. However, it is not clear whether CT is directly related to PDs or whether common familial factors (i.e., shared environment and/or genetic factors) better account for that relationship. The current study used a cotwin control design to examine support for a direct effect of CT on PD criterion counts. Participants were from the Norwegian Twin Registry (N = 2,780), including a subset (n = 898) of twin pairs (449 pairs, 45% monozygotic [MZ]) discordant for CT meeting DSM-IV Posttraumatic Stress Disorder Criterion A. All participants completed the Norwegian version of the Structured Interview for DSM-IV Personality. Significant associations between CT and all PD criterion counts were detected in the general sample; however, the magnitude of observed effects was small, with CT accounting for no more than approximately 1% of variance in PD criterion counts. A significant, yet modest, interactive effect was detected for sex and CT on Schizoid and Schizotypal PD criterion counts, with CT being related to these disorders among women but not men. After common familial factors were accounted for in the discordant twin sample, CT was significantly related to Borderline and Antisocial PD criterion counts, but no other disorders; however, the magnitude of observed effects was quite modest (r2 = .006 for both outcomes), indicating that the small effect observed in the full sample is likely better accounted for by common genetic and/or environmental factors. CT does not appear to be a key factor in PD etiology.

  10. The prevalence of HSV-2 infection in HIV-1 discordant couples.

    Science.gov (United States)

    Duan, S; Ding, Y; Wu, Z; Rou, K; Yang, Y; Wang, J; Gao, M; Ye, R; Xiang, L; He, N

    2016-01-01

    We aimed to investigate the prevalence and associated factors of HSV-2 discordance and concordance in HIV-1-discordant couples. This study used the baseline data from a cohort study of HIV-1-discordant couples in Dehong prefecture of Yunnan province, China. Of 954 participating couples, 42·4% were affected by HSV-2, of which 20·4% were HSV-2-concordant positive, 7·6% were HSV-2-discordant where the male was HSV-2 positive, and 14·4% were HSV-2 discordant where the female was HSV-2 positive. Compared to HSV-2-negative concordance, HSV-2 discordance with an HSV-2-positive male spouse was significantly associated with characteristics of the male spouse, including Han ethnicity and being in a second marriage. HSV-2 discordance with an HSV-2-positive female spouse was significantly associated with characteristics of the female spouse, including Han ethnicity, having engaged in commercial sex, having a sexual relationship of HSV-2 discordance, HSV-2-positive concordance was significantly associated with an education level of middle school or higher for both spouses, a sexual relationship of ⩾3 years, more frequent sex and having an HIV-1-infected male spouse. The findings highlight the need for HSV-2 prevention and treatment efforts to reduce HSV-2 transmission in this population, and emphasize the importance of implementing prevention interventions early in couples' relationships.

  11. Estimating twin concordance for bivariate competing risks twin data.

    Science.gov (United States)

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

    2014-03-30

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

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

    Science.gov (United States)

    Desseauve, D; Voluménie, J-L

    2008-09-01

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

  13. Application of two tests of multivariate discordancy to fisheries data sets

    Science.gov (United States)

    Stapanian, M.A.; Kocovsky, P.M.; Garner, F.C.

    2008-01-01

    The generalized (Mahalanobis) distance and multivariate kurtosis are two powerful tests of multivariate discordancies (outliers). Unlike the generalized distance test, the multivariate kurtosis test has not been applied as a test of discordancy to fisheries data heretofore. We applied both tests, along with published algorithms for identifying suspected causal variable(s) of discordant observations, to two fisheries data sets from Lake Erie: total length, mass, and age from 1,234 burbot, Lota lota; and 22 combinations of unique subsets of 10 morphometrics taken from 119 yellow perch, Perca flavescens. For the burbot data set, the generalized distance test identified six discordant observations and the multivariate kurtosis test identified 24 discordant observations. In contrast with the multivariate tests, the univariate generalized distance test identified no discordancies when applied separately to each variable. Removing discordancies had a substantial effect on length-versus-mass regression equations. For 500-mm burbot, the percent difference in estimated mass after removing discordancies in our study was greater than the percent difference in masses estimated for burbot of the same length in lakes that differed substantially in productivity. The number of discordant yellow perch detected ranged from 0 to 2 with the multivariate generalized distance test and from 6 to 11 with the multivariate kurtosis test. With the kurtosis test, 108 yellow perch (90.7%) were identified as discordant in zero to two combinations, and five (4.2%) were identified as discordant in either all or 21 of the 22 combinations. The relationship among the variables included in each combination determined which variables were identified as causal. The generalized distance test identified between zero and six discordancies when applied separately to each variable. Removing the discordancies found in at least one-half of the combinations (k=5) had a marked effect on a principal components

  14. TWIN GESTATION : A CHALLENGING TASK

    Directory of Open Access Journals (Sweden)

    Vrunda V.

    2015-03-01

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

  15. Twin-twin transfusion syndrome: neurodevelopmental screening test

    Directory of Open Access Journals (Sweden)

    Amabile Vessoni Arias

    2015-03-01

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

  16. Posttraumatic stress disorder, combat exposure, and carotid intima-media thickness in male twins.

    Science.gov (United States)

    Goetz, Margarethe; Shah, Amit; Goldberg, Jack; Cheema, Faiz; Shallenberger, Lucy; Murrah, Nancy V; Bremner, J Douglas; Vaccarino, Viola

    2014-11-15

    Posttraumatic stress disorder (PTSD) is associated with an increased risk of ischemic heart disease, though the pathophysiologic mechanisms remain unclear. Carotid artery intima-media thickness (CIMT) is a measure of subclinical atherosclerosis. We examined whether PTSD and combat exposure were associated with CIMT in Vietnam War-era twins after controlling for shared genetic and childhood factors. Between 2002 and 2010, we studied 465 middle-aged twins from the Vietnam Era Twin Registry who were free from cardiovascular disease. PTSD was diagnosed using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and CIMT was measured by ultrasound. Mixed-effects regression models were used to examine individual, between-pair, and within-pair associations. Approximately 13% of participants met the criteria for PTSD, and 45% served in the Vietnam Theater. PTSD was associated with 32.7 μm higher CIMT (95% confidence interval (CI): 0.9, 64.5) after adjustment for confounders. The average CIMT for the pair increased by 59.7 μm for each additional twin with PTSD (95% CI: 15.9, 104.2). We found no significant within-pair differences in CIMT when comparing PTSD-discordant co-twins. Results for combat exposure were similar, but its association with CIMT weakened after adjustment for PTSD (95% CI: 7.0, 45.3). Among Vietnam War-era veterans, combat exposure and PTSD are associated with CIMT, though the associations are largely mediated by shared childhood factors.

  17. TwinMux Testing System

    CERN Document Server

    Wong, Wei Wen; CERN. Geneva. PH Department

    2015-01-01

    During the CERN summer school program, I joined the CMS Muon Drift Tube (DT) group, and mainly worked on two projects, which, both of them, are related to the electronics of a new data concentrator called the “TwinMux”. My first task within the TwinMux project was to build an integrated software test station in order to run several tests on the functionality of the TwinMux hardware. Essentially, I had to integrate existing testing scripts, adding several new ones, into a single user-friendly testing platform which can perform quick, convenient and automated hardware testing. Later, I was also involved in the design of the local technical triggering of the DT. Such system relies on some firmware functionality built in the TwinMux and controlled by software. I had attempted two different approaches to design the communication topology of all the 12 TwinMux cards in order to send a user-defined logical operation to the read-out electronics. The final goal of this system is to drive local trigger signal for...

  18. TWIN PREGNANCY WITH ACARDIUS ANCEPS

    Directory of Open Access Journals (Sweden)

    Padma

    2014-02-01

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

  19. Influence of genes and environment on brain volumes in twin pairs concordant and discordant for bipolar disorder

    NARCIS (Netherlands)

    Schot, van der A.C.; Vonk, R.; Brans, R.G.H.; Haren, van N.E.M.; Koolschijn, P.C.; Nuboer, V.; Schnack, H.G.; Baal, van G.C.M.; Boomsma, D.I.; Nolen, W.A.; Hulshoff Pol, H.E.; Kahn, R.S.

    2009-01-01

    CONTEXT: Structural neuroimaging studies suggest the presence of subtle abnormalities in the brains of patients with bipolar disorder. The influence of genetic and/or environmental factors on these brain abnormalities is unknown. OBJECTIVE: To investigate the contribution of genetic and environmenta

  20. Data in brief: Transcriptome analysis of induced pluripotent stem cells from monozygotic twins discordant for trisomy 21

    Directory of Open Access Journals (Sweden)

    Youssef Hibaoui

    2014-12-01

    Full Text Available Down syndrome (DS, trisomy 21, is the most common viable chromosomal disorder, with an incidence of 1 in 800 live births. Its phenotypic characteristics include intellectual impairment and several other developmental abnormalities, for the majority of which the pathogenetic mechanisms remain unknown. In this “Data in Brief” paper, we sum up the whole genome analysis by mRNA sequencing of normal and DS induced pluripotent stem cells that was recently published by Hibaoui et al. in EMBO molecular medicine.

  1. Whole blood BDNF levels in healthy twins discordant for affective disorder: association to life events and neuroticism

    DEFF Research Database (Denmark)

    Trajkovska, V.; Vinberg, M.; Aznar, S.

    2008-01-01

    and protected against affective disorder. Whole blood assessed for BDNF concentrations and correlated to risk status, neuroticism, and number of stressful life events. RESULTS: Between the groups, we found no significant difference in whole blood BDNF levels. Women at high-risk for depression who had...... neuroticism scores and two or less recent stressful events were associated with decreased whole blood BDNF levels (n=50, p

  2. Influence of Genes and Environment on Brain Volumes in Twin Pairs Concordant and Discordant for Bipolar Disorder

    NARCIS (Netherlands)

    van der Schot, Astrid C.; Vonk, Ronald; Brans, Rachel G. H.; van Haren, Neeltje E. M.; Koolschijn, P. Cedric M. P.; Nuboer, Valerie; Schnack, Hugo G.; van Baal, G. Caroline M.; Boomsma, Dorret I.; Nolen, Willem A.; Pol, Hilleke E. Hulshoff; Kahn, Rene S.

    2009-01-01

    Context: Structural neuroimaging studies suggest the presence of subtle abnormalities in the brains of patients with bipolar disorder. The influence of genetic and/or environmental factors on these brain abnormalities is unknown. Objective: To investigate the contribution of genetic and environmenta

  3. Complement factor H-associated atypical hemolytic uremic syndrome in monozygotic twins: Concordant presentation, discordant response to treatment

    NARCIS (Netherlands)

    J.C. Davin; K.H. Olie; R. Verlaak; F. Horuz; S. Florquin; J.J. Weening; J.W. Groothoff; L. Strain; T.H.J. Goodship

    2006-01-01

    Hemolytic uremic syndrome not associated with diarrhea (diarrhea negative, atypical) is less common than the diarrhea-positive typical form, but frequently results In end-stage renal failure. Although there are anecdotal cases of successful treatment with fresh frozen plasma alone, the value of this

  4. Characterizing Blood Metabolomics Profiles Associated with Self-Reported Food Intakes in Female Twins.

    Directory of Open Access Journals (Sweden)

    Tess Pallister

    Full Text Available Using dietary biomarkers in nutritional epidemiological studies may better capture exposure and improve the level at which diet-disease associations can be established and explored. Here, we aimed to identify and evaluate reproducibility of novel biomarkers of reported habitual food intake using targeted and non-targeted metabolomic blood profiling in a large twin cohort. Reported intakes of 71 food groups, determined by FFQ, were assessed against 601 fasting blood metabolites in over 3500 adult female twins from the TwinsUK cohort. For each metabolite, linear regression analysis was undertaken in the discovery group (excluding MZ twin pairs discordant [≥1 SD apart] for food group intake with each food group as a predictor adjusting for age, batch effects, BMI, family relatedness and multiple testing (1.17x10-6 = 0.05/[71 food groups x 601 detected metabolites]. Significant results were then replicated (non-targeted: P<0.05; targeted: same direction in the MZ discordant twin group and results from both analyses meta-analyzed. We identified and replicated 180 significant associations with 39 food groups (P<1.17x10-6, overall consisting of 106 different metabolites (74 known and 32 unknown, including 73 novel associations. In particular we identified trans-4-hydroxyproline as a potential marker of red meat intake (0.075[0.009]; P = 1.08x10-17, ergothioneine as a marker of mushroom consumption (0.181[0.019]; P = 5.93x10-22, and three potential markers of fruit consumption (top association: apple and pears: including metabolites derived from gut bacterial transformation of phenolic compounds, 3-phenylpropionate (0.024[0.004]; P = 1.24x10-8 and indolepropionate (0.026[0.004]; P = 2.39x10-9, and threitol (0.033[0.003]; P = 1.69x10-21. With the largest nutritional metabolomics dataset to date, we have identified 73 novel candidate biomarkers of food intake for potential use in nutritional epidemiological studies. We compiled our findings into the

  5. Complications arising in twin pregnancy: findings of prenatal ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Ah; Cho, Jeong Yeon; Lee, Young Ho; Song, Mi Jin; Min, Jee Yeon; Lee, Hak Jong; Han, Byoung Hee; Lee, Kyung Sang; Cho, Byung Jae; Chun, Yi Kyeong [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2003-03-01

    Multifetal gestations are high-risk pregnancies involving higher perinatal morbidity and mortality, and are subject to unique complications including twin oligohydramnios- polyhydramnios sequence, twin-to-twin transfusion syndrome, acardiac twins, conjoined twins, co-twin demise, and heterotopic pregnancies. The purpose of this study is to describe the prenatal ultrasonographic and pathologic findings of these complications.

  6. Nike Twins Seven Seven: Nigerian Batik Artist.

    Science.gov (United States)

    LaDuke, Betty

    1987-01-01

    Chronicles the personal and professional life of Nike Twins Seven Seven (born 1951), a Nigerian batik artist, and her husband, Twins Seven Seven, a musician-artist, both of whom have received international acclaim. (BJV)

  7. Preterm twin gestation and cystic periventricular leucomalacia

    NARCIS (Netherlands)

    Resch, B; Jammernegg, A; Vollaard, E; Maurer, U; Mueller, WD; Pertl, B

    2004-01-01

    Objective: To identify risk factors for the development of cystic periventricular leucomalacia (PVL) in twin gestation. Design: Retrospective case-control study. Setting: Tertiary care university hospital, Department of Paediatrics, Division of Neonatology, Graz, Austria. Patients: Preterm twin gest

  8. Breast-Feeding Twins: Making Feedings Manageable

    Science.gov (United States)

    ... more than one baby? Here's help breast-feeding twins or other multiples, from getting positioned and ensuring ... babies who are born prematurely, as are many twins and higher order multiples. Breast milk is easier ...

  9. Risk of Oral Clefts in Twins

    DEFF Research Database (Denmark)

    Grosen, Dorthe; Bille, Camilla; Petersen, Inge

    2011-01-01

    BACKGROUND:: Small studies have indicated that twinning increases the risk of oral cleft. METHODS:: We used data from a Danish national population-based cohort study to investigate whether twinning was associated with isolated oral cleft, and to estimate the twin probandwise concordance rate...... and heritability. Twins (207 affected/130,710) and singletons (7766 affected/4,798,526) born from 1936 through 2004 in Denmark were ascertained by linkage among the Danish Facial Cleft Database, the Danish Twin Registry, and the Civil Registration System. We computed oral cleft prevalence and prevalence proportion...... ratio for twins versus singletons, stratified for 3 subphenotypes. Probandwise concordance rates and heritability for twins were estimated for 2 phenotypes-cleft lip with or without cleft palate (CL/P) and cleft palate (CP). RESULTS:: The prevalence of oral cleft was 15.8 per 10,000 twins and 16.6 per...

  10. Having Twins? How to Stay Healthy

    Science.gov (United States)

    ... Listen Español Text Size Email Print Share Having Twins? How to Stay Healthy Page Content Article Body ... the eyes of obstetricians. Many would call a twin pregnancy a high-risk pregnancy , but don’t ...

  11. Quantum discord bounds the amount of distributed entanglement.

    Science.gov (United States)

    Chuan, T K; Maillard, J; Modi, K; Paterek, T; Paternostro, M; Piani, M

    2012-08-17

    The ability to distribute quantum entanglement is a prerequisite for many fundamental tests of quantum theory and numerous quantum information protocols. Two distant parties can increase the amount of entanglement between them by means of quantum communication encoded in a carrier that is sent from one party to the other. Intriguingly, entanglement can be increased even when the exchanged carrier is not entangled with the parties. However, in light of the defining property of entanglement stating that it cannot increase under classical communication, the carrier must be quantum. Here we show that, in general, the increase of relative entropy of entanglement between two remote parties is bounded by the amount of nonclassical correlations of the carrier with the parties as quantified by the relative entropy of discord. We study implications of this bound, provide new examples of entanglement distribution via unentangled states, and put further limits on this phenomenon.

  12. Non-orthodox combinatorial models based on discordant structures

    CERN Document Server

    Romanov, V F

    2010-01-01

    This paper introduces a novel method for compact representation of sets of n-dimensional binary sequences in a form of compact triplets structures (CTS), supposing both logic and arithmetic interpretations of data. Suitable illustration of CTS application is the unique graph-combinatorial model for the classic intractable 3-Satisfiability problem and a polynomial algorithm for the model synthesis. The method used for Boolean formulas analysis and classification by means of the model is defined as a bijective mapping principle for sets of components of discordant structures to a basic set. The statistic computer-aided experiment showed efficiency of the algorithm in a large scale of problem dimension parameters, including those that make enumeration procedures of no use. The formulated principle expands resources of constructive approach to investigation of intractable problems.

  13. Cardiac contraction induces discordant alternans and localized block

    Science.gov (United States)

    Radszuweit, M.; Alvarez-Lacalle, E.; Bär, M.; Echebarria, B.

    2015-02-01

    In this paper we use a simplified model of cardiac excitation-contraction coupling to study the effect of tissue deformation on the dynamics of alternans, i.e., alternations in the duration of the cardiac action potential, that occur at fast pacing rates and are known to be proarrhythmic. We show that small stretch-activated currents can produce large effects and cause a transition from in-phase to off-phase alternations (i.e., from concordant to discordant alternans) and to conduction blocks. We demonstrate numerically and analytically that this effect is the result of a generic change in the slope of the conduction velocity restitution curve due to electromechanical coupling. Thus, excitation-contraction coupling can potentially play a relevant role in the transition to reentry and fibrillation.

  14. Quantum discord and other measures of quantum correlation

    CERN Document Server

    Modi, Kavan; Cable, Hugo; Paterek, Tomasz; Vedral, Vlatko

    2011-01-01

    One of the best signatures of nonclassicality in a quantum system is the existence of correlations that have no classical counterpart. Different methods for quantifying the quantum and classical parts of the correlations are amongst the most actively-studied topics of quantum information theory in the past decade. Entanglement is the most prominent of these correlations, but in many cases unentangled states exhibit nonclassical behavior. Thus distinguishing quantum correlation other than entanglement provides a better division between the quantum and classical worlds, especially when considering mixed states. Here we review different notions of classical and quantum correlations quantified by quantum discord and other related measures. In the first half we review the mathematical properties of the measures of quantum correlation, relate them to each other, and discuss the classical-quantum division that is common among them. In the second half, we show that the measures quantum correlation identify and quanti...

  15. Twin TQFTs and Frobenius Algebras

    Directory of Open Access Journals (Sweden)

    Carmen Caprau

    2013-01-01

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

  16. Twins or two single children

    Directory of Open Access Journals (Sweden)

    2002-08-01

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

  17. Do Twin Boundaries Always Strengthen Metal Nanowires?

    OpenAIRE

    Zhang Yongfeng; Huang Hanchen

    2008-01-01

    Abstract It has been widely reported that twin boundaries strengthen nanowires regardless of their morphology—that is, the strength of nanowires goes up as twin spacing goes down. This article shows that twin boundaries do not always strengthen nanowires. Using classical molecular dynamics simulations, the authors show that whether twin boundaries strengthen nanowires depends on the necessary stress for dislocation nucleation, which in turn depends on surface morphologies. When nanowire...

  18. Kynurenic acid and psychotic symptoms and personality traits in twins with psychiatric morbidity.

    Science.gov (United States)

    Kegel, Magdalena E; Johansson, Viktoria; Wetterberg, Lennart; Bhat, Maria; Schwieler, Lilly; Cannon, Tyrone D; Schuppe-Koistinen, Ina; Engberg, Göran; Landén, Mikael; Hultman, Christina M; Erhardt, Sophie

    2017-01-01

    Increased cytokines and kynurenic acid (KYNA) levels in cerebrospinal fluid (CSF) have been reported in patients with schizophrenia and bipolar disorder. The aim of the present study was to investigate cytokines and kynurenines in the CSF of twin pairs discordant for schizophrenia or bipolar disorder and to study these CSF markers in relation to psychotic symptoms and personality traits. CSF levels of tryptophan (TRP), KYNA, quinolinic acid (QUIN), interleukin (IL)-6, IL-8 and tumor necrosis factor-alpha (TNF-α) were analyzed in 23 twins with schizophrenia or bipolar disorder, and in their not affected co-twins. Ratings of psychotic symptoms and personality traits were made using the Scales for Assessment of Negative and Positive symptoms, the Structured Clinical Interview for DSM-IV - Axis II Disorders, and the Schizotypal Personality Questionnaire - Brief. A total score for psychotic symptoms and personality traits was constructed for analysis. CSF KYNA was associated with the score for psychotic symptom and personality traits. TNF-α and IL-8 were associated, and the intra-pair differences scores of TNF-α and IL-8 were highly correlated. Intraclass correlations indicated genetic influences on CSF KYNA, TRP, IL-8 and TNF-α. The association between KYNA and psychotic symptoms further supports a role of KYNA in psychotic disorders.

  19. Twins reunited: scientific and personal perspectives/twin research studies: multiple birth effects on IQ and body size; life style, muscles, and metabolism; monochorionic dizygotic twin with blood chimerism; amniocentesis for twins/twins in the media: identical doctors; freedom fighter for twins; twin scholarships; Auguste and Jean-Felix Piccard; twins born apart.

    Science.gov (United States)

    Segal, Nancy L; Mulligan, Christy A

    2014-04-01

    A reunion of 38-year-old female monozygotic twins took place in Daegu, South Korea, on January 14, 2014. Scientific and personal perspectives on this extraordinary event are provided. A review of timely twin research follows, covering the effects of multiple births on IQ and body size, lifestyle and physical fitness associations, a rare case of a dizygotic twin with blood chimerism and definitional issues surrounding amniocentesis-related loss in multiple birth pregnancies. Interesting and informative mention of twins in the media includes twin doctors, a twin freedom fighter, the availability of college scholarships for twins, a new book about the Piccard family (two of whose members were twins), and co-twins born before and after the new year. A follow-up to a previous mention of identical twin biatheletes is also provided.

  20. Twin and genetic effects on life events

    NARCIS (Netherlands)

    Middeldorp, C.M.; Cath, D.C.; Vink, J.M.; Boomsma, D.I.

    2005-01-01

    Twin studies that examine the effect of specific environmental risk factors on psychiatric disorders assume that there are no differences in prevalences of these risk factors between twins and singletons. Violation of this assumption signifies that the results from twin studies might not generalize

  1. [The diagnostic algorithm in twin pregnancy].

    Science.gov (United States)

    Ropacka-Lesiak, Mariola; Szaflik, Krzysztof; Breborowicz, Grzegorz H

    2015-03-01

    This paper presents the diagnostic algorithm in twin pregnancy. The most important sonographic parameters in the assessment of twins have been discussed. Moreover, the most significant complications of twin pregnancy as well as diagnostic possibilities and management, have been also presented and defined.

  2. Natal Influences and Twin Differences: Draft.

    Science.gov (United States)

    Van den Daele, Leland D.

    1972-01-01

    A classification of natal influences is proposed with a model of their operation. Natal influences affect maternal capacity, maternal load, and maternal efficiency. Since maternal load is increased in twin pregnancy, results of twin studies must be generalized with caution. The method of co-twin control is exemplified by examination of a small…

  3. A RARE CASE OF ACARDIAC TWIN

    OpenAIRE

    Padmaja; Nirmala,

    2015-01-01

    Fetus Acardiacus is a very rare manifestation of twin gestation . This happens due to TRAP sequence . That is Twin reversed arterial perfusion . In this case an amorphous mass was seen on a routine antenatal scan and followed as there was a live twin also . The case report highlights the importance of careful scanning and ...

  4. MIR phasing using merohedrally twinned crystals

    NARCIS (Netherlands)

    Terwisscha van Scheltinga, Anke C.; Valegård, Karin; Hajdu, Janos; Andersson, Inger

    2003-01-01

    Merohedral twinning is a crystal-growth disorder that seriously hinders the determination of macromolecular crystal structures by isomorphous replacement. The strategies used in the structures solved so far are discussed. Several methods can be used to determine the extent of twinning, the twin frac

  5. A Twin Study of Perthes Disease

    DEFF Research Database (Denmark)

    Metcalfe, David; Van Dijck, Stephanie; Parsons, Nicolas;

    2016-01-01

    and genetic associations with LCPD. METHODS: We extracted all twin pairs from the Danish Twin Registry (DTR) in which at least 1 individual had LCPD. The DTR captures every twin pair born alive in Denmark, and those with LCPD were identified by using health record linkage. Probanwise concordance...

  6. Multiple rectal carcinoid tumors in monozygotic twins.

    Science.gov (United States)

    Doi, Momoko; Ikawa, Osamu; Taniguchi, Hiroki; Kawamura, Takuji; Katsura, Kanade

    2016-08-01

    We report multiple rectal carcinoid tumors in monozygotic twins who, respectively, had 42 and 36 carcinoid tumors in the lower rectum. This is the first report about carcinoid tumors in monozygotic twins. Both twins developed a similar number of rectal carcinoids with a similar distribution. Investigation of their genetic background may provide information about the origin of these tumors.

  7. Postpartum Mental State of Mothers of Twins

    Science.gov (United States)

    Brantmüller, Éva; Gyúró, Mónika; Galgán, Kitti; Pakai, Annamária

    2016-01-01

    Twin birth is a relevant risk factor for postnatal depression (PND). The primary objective of our study is to reveal the prevalence of suspected cases of depression and to identify some background factors among mothers of twins. We applied convenience sampling method within a retrospective, quantitative study among mothers given birth to twins for…

  8. Concordance for multiple sclerosis in Danish twins

    DEFF Research Database (Denmark)

    Hansen, T; Skytthe, Axel; Stenager, Egon

    2005-01-01

    The occurrence of multiple sclerosis (MS) in twins has not previously been studied in complete nationwide data sets. The existence of almost complete MS and twin registries in Denmark ensures that essentially unbiased samples of MS cases among twins can be obtained. In this population-based study...

  9. The Charles Perkins Centre's Twins Research Node.

    Science.gov (United States)

    Ferreira, Lucas C; Craig, Jeffrey M; Hopper, John L; Carrick, Susan E

    2016-08-01

    Twins can help researchers disentangle the roles of genes from those of the environment on human traits, health, and diseases. To realize this potential, the Australian Twin Registry (ATR), University of Melbourne, and the Charles Perkins Centre (CPC), University of Sydney, established a collaboration to form the Twins Research Node, a highly interconnected research facility dedicated specifically to research involving twins. This collaboration aims to foster the adoption of twin designs as important tools for research in a range of health-related domains. The CPC hosted their Twins Research Node's launch seminar entitled 'Double the power of your research with twin studies', in which experienced twin researchers described how twin studies are supporting scientific discoveries and careers. The launch also featured twin pairs who have actively participated in research through the ATR. Researchers at the CPC were surveyed before the event to gauge their level of understanding and interest in utilizing twin research. This article describes the new Twins Research Node, discusses the survey's main results and reports on the launch seminar.

  10. Disclosure of HIV results among discordant couples in Rakai, Uganda: a facilitated couple counselling approach.

    Science.gov (United States)

    Kairania, Robert; Gray, Ronald H; Kiwanuka, Noah; Makumbi, Fredrick; Sewankambo, Nelson K; Serwadda, David; Nalugoda, Fred; Kigozi, Godfrey; Semanda, John; Wawer, Maria J

    2010-09-01

    Disclosure of HIV sero-positive results among HIV-discordant couples in sub-Saharan Africa is generally low. We describe a facilitated couple counselling approach to enhance disclosure among HIV-discordant couples. Using unique identifiers, 293 HIV-discordant couples were identified through retrospective linkage of married or cohabiting consenting adults individually enrolled into a cohort study and into two randomised trials of male circumcision in Rakai, Uganda. HIV-discordant couples and a random sample of HIV-infected concordant and HIV-negative concordant couples (to mask HIV status) were invited to sensitisation meetings to discuss the benefits of disclosure and couple counselling. HIV-infected partners were subsequently contacted to encourage HIV disclosure to their HIV-uninfected partners. If the index positive partner agreed, the counsellor facilitated the disclosure of HIV results, and provided ongoing support. The proportion of disclosure was determined. Eighty-one per cent of HIV-positive partners in discordant relationships disclosed their status to their HIV-uninfected partners in the presence of the counsellor. The rates of disclosure were 81.3% in male HIV-positive and 80.2% in female HIV-positive discordant couples. Disclosure did not vary by age, education or occupation. In summary, disclosure of HIV-positive results in discordant couples using facilitated couple counselling approach is high, but requires a stepwise process of sensitisation and agreement by the infected partner.

  11. Glide twinning and pseudotwinning in peristerite: twin morphology and propagation

    Science.gov (United States)

    Brown, William L.

    1989-07-01

    Optically visible Albite glide “twins” in a peristerite (˜An9Or1.6), identified from their tapering shape and relationship to grain boundaries, were studied by transmission electron microscopy. Near the tips in sections ⊥ a, the microstructure consists of small (˜400 nm long) lensshaped Albite twins centred exclusively on the oligoclase lamellae. The lenses extend partly outwards into the two adjacent low albite lamellae and induce strong inhomogeneous strain. Where the lenses are closer together, they form, depending on the sense of shear, nearly linear left or right-stepping en échelon arrays, with overlap of the strain fields. Slightly farther in from the tip, the twin domains coalesce to form continuous pinch-and-swell lamellae, being always thicker in the oligoclase. Because of Si,Al order, only elastic glide pseudotwins are possible in low albite. In oligoclase glide pseudotwins may be mechanically stable (metastable relative to Si,Al order) and may deviate only slightly from true twins. Pseudotwins develop first in the oligoclase, propagate dynamically by jumping across the intervening albite lamellae, extend lengthways and thicken sideways and finally coalesce. They are stabilized by diffusion-controlled inversion of Si,Al order giving rise to true twins described in a companion paper.

  12. NOTE: Increasing cardiac output and decreasing oxygenation sequence in pump twins of acardiac twin pregnancies

    Science.gov (United States)

    van Gemert, Martin J. C.; Umur, Asli; van den Wijngaard, Jeroen P. H. M.; Van Bavel, Ed; Vandenbussche, Frank P. H. A.; Nikkels, Peter G. J.

    2005-02-01

    An acardiac twin pregnancy is a rare but serious complication of monochorionic twinning and consists of an acardiac twin and a pump twin. The acardiac twin is a severely malformed fetus that lacks most organs, particularly a heart, but grows during pregnancy because it is perfused by the developmentally normal pump twin via a set of arterioarterial and venovenous placental anastomoses. Pump twins die intrauterine or neonatally in about 50% of the cases. Because the effects of an acardiac mass on the pump twin's development are incompletely known, methods for outcome prognosis are currently not available. We sought to derive simple relations for the pump twin's excess cardiac output and decreased oxygenation and to use available clinical cases for a preliminary test of the model. As a method, we used a theoretical flow model to represent the fetoplacental circulation of an acardiac twin pregnancy and estimated blood deoxygenation and reoxygenation following perfusion of the two bodies and placentas, respectively. The results show the pump twin's excess cardiac output and decrease of venous oxygen saturation to depend on the ratio of pump twin to acardiac twin umbilical blood flow, whose ratio can be measured by ultrasonography. The clinical cases show a decreasing umbilical flow ratio with gestation. In conclusion, prospective serial study is necessary to test whether measurement of umbilical flow ratios allows monitoring the pump twin's pathophysiologic development, possibly resulting in a guideline for prognosis of pump twin survival.

  13. Increasing cardiac output and decreasing oxygenation sequence in pump twins of acardiac twin pregnancies

    Energy Technology Data Exchange (ETDEWEB)

    Gemert, Martin J C van [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam (Netherlands); Umur, Asli [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam (Netherlands); Wijngaard, Jeroen P H M van den [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam (Netherlands); VanBavel, Ed [Department of Medical Physics, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Vandenbussche, Frank P H A [Department of Obstetrics, Leiden University Medical Center, Leiden (Netherlands); Nikkels, Peter G J [Department of Pathology, University Medical Center, Utrecht (Netherlands)

    2005-02-07

    An acardiac twin pregnancy is a rare but serious complication of monochorionic twinning and consists of an acardiac twin and a pump twin. The acardiac twin is a severely malformed fetus that lacks most organs, particularly a heart, but grows during pregnancy because it is perfused by the developmentally normal pump twin via a set of arterioarterial and venovenous placental anastomoses. Pump twins die intrauterine or neonatally in about 50% of the cases. Because the effects of an acardiac mass on the pump twin's development are incompletely known, methods for outcome prognosis are currently not available. We sought to derive simple relations for the pump twin's excess cardiac output and decreased oxygenation and to use available clinical cases for a preliminary test of the model. As a method, we used a theoretical flow model to represent the fetoplacental circulation of an acardiac twin pregnancy and estimated blood deoxygenation and reoxygenation following perfusion of the two bodies and placentas, respectively. The results show the pump twin's excess cardiac output and decrease of venous oxygen saturation to depend on the ratio of pump twin to acardiac twin umbilical blood flow, whose ratio can be measured by ultrasonography. The clinical cases show a decreasing umbilical flow ratio with gestation. In conclusion, prospective serial study is necessary to test whether measurement of umbilical flow ratios allows monitoring the pump twin's pathophysiologic development, possibly resulting in a guideline for prognosis of pump twin survival. (note)

  14. The 'Planemo' Twins

    Science.gov (United States)

    2006-08-01

    The cast of exoplanets has an extraordinary new member. Using ESO's telescopes, astronomers have discovered an approximately seven-Jupiter-mass companion to an object that is itself only twice as hefty. Both objects have masses similar to those of extra-solar giant planets, but they are not in orbit around a star - instead they appear to circle each other. The existence of such a double system puts strong constraints on formation theories of free-floating planetary mass objects. ESO PR Photo 29a/06 ESO PR Photo 29a/06 Double System of Planetary Mass Objects (Artist's View) Ray Jayawardhana of the University of Toronto (Canada) and Valentin D. Ivanov of ESO report the discovery in the August 3 issue of Science Express, the rapid online publication service of the journal Science. "This is a truly remarkable pair of twins - each having only about one percent the mass of our Sun," said Jayawardhana. "Its mere existence is a surprise, and its origin and fate a bit of a mystery." Roughly half of all Sun-like stars come in pairs. So do about a sixth of brown dwarfs, 'failed stars' that have less than 75 Jupiter masses and are unable to sustain nuclear fusion in their cores. During the past five years, astronomers have identified a few dozen of even smaller free-floating planetary mass objects, or planemos, in nearby star forming regions. Oph 162225-240515, or Oph1622 for short, is the first planemo found to be a double. The researchers discovered the companion candidate in an optical image taken with ESO's 3.5-m New Technology Telescope at La Silla, Chile. They decided to take optical spectra and infrared images of the pair with ESO's 8.2-m Very Large Telescope to make sure that it is a true companion, instead of a foreground or background star that happens to be in the same line of sight. These follow up observations indeed confirmed that both objects are young, at the same distance, and much too cool to be stars. This suggests the two are physically associated. ESO PR

  15. Twin-Arginine Protein Translocation

    NARCIS (Netherlands)

    Goosens, Vivianne J; van Dijl, Jan Maarten

    2016-01-01

    Twin-arginine protein translocation systems (Tat) translocate fully folded and co-factor-containing proteins across biological membranes. In this review, we focus on the Tat pathway of Gram-positive bacteria. The minimal Tat pathway is composed of two components, namely a TatA and TatC pair, which a

  16. Twin and family studies reveal strong environmental and weaker genetic cues explaining heritability of eosinophilic esophagitis

    Science.gov (United States)

    Alexander, Eileen S.; Martin, Lisa J.; Collins, Margaret H.; Kottyan, Leah; Sucharew, Heidi; He, Hua; Mukkada, Vincent A.; Succop, Paul A.; Abonia, J. Pablo; Foote, Heather; Eby, Michael D.; Grotjan, Tommie M.; Greenler, Alexandria J.; Dellon, Evan S.; Demain, Jeffrey G.; Furuta, Glenn T.; Gurian, Larry E.; Harley, John B.; Hopp, Russell J.; Kaul, Ajay; Nadeau, Kari C.; Noel, Richard J.; Putnam, Philip E.; von Tiehl, Karl F.; Rothenberg, Marc E.

    2014-01-01

    Background Eosinophilic esophagitis (EoE) is a chronic antigen-driven allergic inflammatory disease, likely involving the interplay of genetic and environmental factors, yet their respective contributions to heritability are unknown. Objective To quantify risk associated with genes and environment on familial clustering of EoE. Methods Family history was obtained from a hospital-based cohort of 914 EoE probands, (n=2192 first-degree “Nuclear-Family” relatives) and the new international registry of monozygotic and dizygotic twins/triplets (n=63 EoE “Twins” probands). Frequencies, recurrence risk ratios (RRRs), heritability and twin concordance were estimated. Environmental exposures were preliminarily examined. Results Analysis of the Nuclear-Family–based cohort revealed that the rate of EoE, in first-degree relatives of a proband, was 1.8% (unadjusted) and 2.3% (sex-adjusted). RRRs ranged from 10–64, depending on the family relationship, and were higher in brothers (64.0; p=0.04), fathers (42.9; p=0.004) and males (50.7; p<0.001) compared to sisters, mothers and females, respectively. Risk of EoE for other siblings was 2.4%. In the Nuclear-Families, combined gene and common environment heritability (hgc2) was 72.0±2.7% (p<0.001). In the Twins cohort, genetic heritability was 14.5±4.0% (p<0.001), and common family environment contributed 81.0±4% (p<0.001) to phenotypic variance. Proband-wise concordance in MZ co-twins was 57.9±9.5% compared to 36.4±9.3% in DZ (p=0.11). Greater birth-weight difference between twins (p=0.01), breastfeeding (p=0.15) and Fall birth season (p=0.02) were associated with twin discordance in disease status. Conclusions EoE recurrence risk ratios are increased 10–64-fold compared with the general population. EoE in relatives is 1.8–2.4%, depending upon relationship and sex. Nuclear-Family heritability appeared to be high (72.0%). However, Twins cohort analysis revealed a powerful role for common environment (81

  17. Playing a Musical Instrument as a Protective Factor against Dementia and Cognitive Impairment: A Population-Based Twin Study

    Directory of Open Access Journals (Sweden)

    M. Alison Balbag

    2014-01-01

    Full Text Available Increasing evidence supports that playing a musical instrument may benefit cognitive development and health at young ages. Whether playing an instrument provides protection against dementia has not been established. In a population-based cotwin control study, we examined the association between playing a musical instrument and whether or not the twins developed dementia or cognitive impairment. Participation in playing an instrument was taken from informant-based reports of twins’ leisure activities. Dementia diagnoses were based on a complete clinical workup using standard diagnostic criteria. Among 157 twin pairs discordant for dementia and cognitive impairment, 27 pairs were discordant for playing an instrument. Controlling for sex, education, and physical activity, playing a musical instrument was significantly associated with less likelihood of dementia and cognitive impairment (odds ratio [OR] = 0.36 [95% confidence interval 0.13–0.99]. These findings support further consideration of music as a modifiable protective factor against dementia and cognitive impairment.

  18. Twin vaginal delivery: innovate or abdicate.

    Science.gov (United States)

    Easter, Sarah Rae; Taouk, Laura; Schulkin, Jay; Robinson, Julian N

    2017-02-07

    Neonatal safety data along with national guidelines have prompted renewed interest in vaginal delivery of twins, particularly in the case of the noncephalic second twin. Yet, the rising rate of twin cesarean deliveries, coupled with the national decline in operative obstetrics, raises concerns about the availability of providers who are skilled in twin vaginal birth. Providers are key stakeholders for increasing rates of twin vaginal delivery. We surveyed a group of practicing obstetricians to explore potential barriers to the vaginal birth of twins with a focus on delivery of the noncephalic second twin. Among 107 responding providers, only 57% would deliver a noncephalic second twin by breech extraction. Providers who preferred breech extraction had a higher rate of maternal-fetal medicine subspecialty training (26.2% vs 4.3%; P30 sets of twins annually (57.4% vs 34.8%; P=.02). Most providers (54.2%) were familiar with the findings from the recent randomized trial that demonstrated the safety of twin vaginal birth. However, knowledge of the trial was not associated statistically with a preference for breech extraction (62.3% vs 43.5%; P=.05). Providers who preferred breech extraction were more likely to agree with recent society guidelines that encourage the vaginal birth of twins (86.9% vs 63.0%; Pinnovation. Without novel provider-focused strategies, we may relinquish passively the requisite skills for not only our patients but also for future generations of obstetricians.

  19. Do Twin Boundaries Always Strengthen Metal Nanowires?

    Science.gov (United States)

    Zhang, Yongfeng; Huang, Hanchen

    2009-01-01

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

  20. Do Twin Boundaries Always Strengthen Metal Nanowires?

    Directory of Open Access Journals (Sweden)

    Zhang Yongfeng

    2008-01-01

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

  1. TRAP Sequence - An Interesting Entity in Twins

    Directory of Open Access Journals (Sweden)

    R H Srinivas Prasad

    2012-01-01

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

  2. Comparison of quantum discord and fully entangled fraction of two classes of d⊗ d^2 states

    Science.gov (United States)

    Behdani, Javad; Akhtarshenas, Seyed Javad; Sarbishaei, Mohsen

    2017-01-01

    The quantumness of a generic state is the resource of many applications in quantum information theory, and it is interesting to survey the measures which are able to detect its trace in the properties of the state. In this work, we study the quantum discord and fully entangled fraction of two classes of bipartite states and compare their behaviors. These classes are complements to the d⊗ d Werner and isotropic states, in the sense that each class possesses the same purification as the corresponding complemental class of states. Our results show that maximally entangled mixed states are also maximally discordant states, leading to a generalization of the well-known fact that all maximally entangled pure states have also maximum quantum discord. Moreover, it is shown that the separability-entanglement boundary of a Werner or isotropic state is manifested as an inflection point in the diagram of quantum discord of the corresponding complemental state.

  3. Breast lesions with discordant results on ultrasound-guided core needle biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Jin Hee; Ko, Eun Young; Kim, Min Jeong; Lee, Kwan Seop; Lee Yul; Bae, Sang Hoon; Min, Soo Kee [Hallym University College of Medicine, Anyang (Korea, Republic of)

    2006-03-15

    We wanted to evaluate the characteristics of those lesions showing insufficient results on ultrasound-guided core needle biopsy. We retrospectively reviewed the pathologic results of 131 lesions from patients who underwent ultrasound-guided core needle biopsy following Mammotome or surgical excisional biopsy from January 2004 to December 2004. Compared with excisional biopsy, ultrasound-guided core needle biopsy showed 14 lesions with discordant results and 9 lesions with indeterminate results. 5 lesions were overestimated and 9 lesions were underestimated on the core needle biopsies. According to the histological tumor types, the papillary tumors showed 66.6% discordance or indetermination, and the phyllodes tumors showed 50% discordance or indetermination. On the results of core needle biopsy, discordant or indeterminate results were frequently reported for papillary and phyllodes tumor. Therefore, excisional biopsy is recommended for these types of tumor.

  4. When faith divides family: religious discord and adolescent reports of parent-child relations.

    Science.gov (United States)

    Stokes, Charles E; Regnerus, Mark D

    2009-03-01

    What happens to family relations when an adolescent and her parent do not share the same religious convictions or practices? Whereas previous work on religion and intergenerational relations looks at relationships between parents and their adult children, we shift the focus to younger families, assessing how parent-child religious discord affects adolescents' evaluation of their relationship with their parents. Exploring data from the National Longitudinal Study of Adolescent Health, we find several interesting patterns of association between religious discord and parent-child relations. Overall, religious discord predicts lower quality intergenerational relations. When parents value religion more than their teens do, adolescents tend to report poorer relations with parents. Relationship quality is not lower, however, when it is the adolescent who values religion more highly. We also find that religious discord is more aggravating in families where parent and child share religious affiliation and in families where the parent is an evangelical Protestant.

  5. An introduction to quantum discord and non-classical correlations beyond entanglement

    CERN Document Server

    Adesso, Gerardo; Bromley, Thomas R

    2016-01-01

    In this didactic article we explore the concept of quantum correlations beyond entanglement. We begin by introducing and motivating the classically correlated states and then showing how to quantify the quantum correlations using an entropic approach, arriving at a well known measure called the quantum discord. Quantum correlations and discord are then operationally linked with the task of local broadcasting. We conclude by providing some alternative perspectives on quantum correlations and how to measure them.

  6. Peer review of grant applications: a simple method to identify proposals with discordant reviews.

    Science.gov (United States)

    Giraudeau, Bruno; Leyrat, Clémence; Le Gouge, Amélie; Léger, Julie; Caille, Agnès

    2011-01-01

    Grant proposals submitted for funding are usually selected by a peer-review rating process. Some proposals may result in discordant peer-review ratings and therefore require discussion by the selection committee members. The issue is which peer-review ratings are considered as discordant. We propose a simple method to identify such proposals. Our approach is based on the intraclass correlation coefficient, which is usually used in assessing agreement in studies with continuous ratings.

  7. Discordant phenotype in siblings with X-linked agammaglobulinemia

    Energy Technology Data Exchange (ETDEWEB)

    Bykowsky, M.J.; Veksler, K.S.; Sullivan, K.E. [Children`s Hospital, Philadelphia, PA (United States)] [and others

    1996-03-01

    X-linked agammaglobulinemia (XLA) is a congenital humoral immunodeficiency caused by a defect in a B-cell-specific signaling molecule, Btk. There has been little concordance of phenotype with genotype in this disorder, and defects in Btk cause immunodeficiencies that range from mild impairment to complete inability to produce antibodies. The factors modifying the phenotype of XLA are not understood. The current study is the first description of two male siblings with identical T{sup 134}{yields}C mutations in the translation initiation ATG of Btk who have different clinical phenotypes as well as different laboratory phenotypes. The proband lacks immunoglobulins and B cells and has recurrent infections, while the elder, affected brother has normal levels of IgG and IgM and very few infections. Both have undetectable levels of Btk kinase activity in circulating mononuclear cells. Complete sequencing of Btk gene transcripts in both brothers revealed no additional mutations to account for the discordant phenotypes. This description provides unequivocal evidence that the phenotype of XLA is influenced by factors additional to the Btk gene. 39 refs., 3 figs., 3 tabs.

  8. Discordant introgression in a rapidly expanding hybrid swarm

    Science.gov (United States)

    Ward, Jessica L.; Blum, Mike J.; Walters, David M.; Porter, Brady A.; Burkhead, Noel; Freeman, Byron

    2012-01-01

    The erosion of species boundaries can involve rapid evolutionary change. Consequently, many aspects of the process remain poorly understood, including the formation, expansion, and evolution of hybrid swarms. Biological invasions involving hybridization present exceptional opportunities to study the erosion of species boundaries because timelines of interactions and outcomes are frequently well known. Here, we examined clinal variation across codominant and maternally inherited genetic markers as well as phenotypic traits to characterize the expansion and evolution of a hybrid swarm between native Cyprinella venusta and invasive Cyprinella lutrensis minnows. Discordant introgression of phenotype, microsatellite multilocus genotype, and mtDNA haplotype indicates that the observable expansion of the C. venusta x C. lutrensis hybrid swarm is a false invasion front. Both parental and hybrid individuals closely resembling C. lutrensis are numerically dominant in the expansion wake, indicating that the non-native parental phenotype may be selectively favored. These findings show that cryptic introgression can extend beyond the phenotypic boundaries of hybrid swarms and that hybrid swarms likely expand more rapidly than can be documented from phenotypic variation alone. Similarly, dominance of a single parental phenotype following an introduction event may lead to instances of species erosion being mistaken for species displacement without hybridization.

  9. Time Series Discord Detection in Medical Data using a Parallel Relational Database [PowerPoint

    Energy Technology Data Exchange (ETDEWEB)

    Woodbridge, Diane; Wilson, Andrew T.; Rintoul, Mark Daniel; Goldstein, Richard H.

    2015-11-01

    Recent advances in sensor technology have made continuous real-time health monitoring available in both hospital and non-hospital settings. Since data collected from high frequency medical sensors includes a huge amount of data, storing and processing continuous medical data is an emerging big data area. Especially detecting anomaly in real time is important for patients’ emergency detection and prevention. A time series discord indicates a subsequence that has the maximum difference to the rest of the time series subsequences, meaning that it has abnormal or unusual data trends. In this study, we implemented two versions of time series discord detection algorithms on a high performance parallel database management system (DBMS) and applied them to 240 Hz waveform data collected from 9,723 patients. The initial brute force version of the discord detection algorithm takes each possible subsequence and calculates a distance to the nearest non-self match to find the biggest discords in time series. For the heuristic version of the algorithm, a combination of an array and a trie structure was applied to order time series data for enhancing time efficiency. The study results showed efficient data loading, decoding and discord searches in a large amount of data, benefiting from the time series discord detection algorithm and the architectural characteristics of the parallel DBMS including data compression, data pipe-lining, and task scheduling.

  10. Time Series Discord Detection in Medical Data using a Parallel Relational Database

    Energy Technology Data Exchange (ETDEWEB)

    Woodbridge, Diane; Rintoul, Mark Daniel; Wilson, Andrew T.; Goldstein, Richard

    2015-10-01

    Recent advances in sensor technology have made continuous real-time health monitoring available in both hospital and non-hospital settings. Since data collected from high frequency medical sensors includes a huge amount of data, storing and processing continuous medical data is an emerging big data area. Especially detecting anomaly in real time is important for patients’ emergency detection and prevention. A time series discord indicates a subsequence that has the maximum difference to the rest of the time series subsequences, meaning that it has abnormal or unusual data trends. In this study, we implemented two versions of time series discord detection algorithms on a high performance parallel database management system (DBMS) and applied them to 240 Hz waveform data collected from 9,723 patients. The initial brute force version of the discord detection algorithm takes each possible subsequence and calculates a distance to the nearest non-self match to find the biggest discords in time series. For the heuristic version of the algorithm, a combination of an array and a trie structure was applied to order time series data for enhancing time efficiency. The study results showed efficient data loading, decoding and discord searches in a large amount of data, benefiting from the time series discord detection algorithm and the architectural characteristics of the parallel DBMS including data compression, data pipe-lining, and task scheduling.

  11. Enhancing Quantum Discord in Cavity QED by Applying Classical Driving Field

    Institute of Scientific and Technical Information of China (English)

    QIAN Yi; XU Jing-Bo

    2012-01-01

    We investigate the quantum discord dynamics in a cavity quantum electrodynamics system, which consists of two noninteracting two-level atoms driven by independent optical Gelds and classical fields, and find that the quantum discord vanishes only asymptotically although entanglement disappears suddenly during the time evolution in the absence of classical fields. It is shown that the amount of quantum discord can be increased by adjusting the classical driving fields because the increasing degree of the amount of quantum mutual information is greater than classical correlation by applying the classical driving fields. Finally, the influence of the classical driving field on the fidelity of the system is also examined.%We investigate the quantum discord dynamics in a cavity quantum electrodynamics system,which consists of two noninteracting two-level atoms driven by independent optical fields and classical fields,and find that the quantum discord vanishes only asymptotically although entanglement disappears suddenly during the time evolution in the absence of classical fields.It is shown that the amount of quantum discord can be increased by adjusting the classical driving fields because the increasing degree of the amount of quantum mutual information is greater than classical correlation by applying the classical driving fields.Finally,the influence of the classical driving field on the fidelity of the system is also examined.

  12. Studies of X inactivation and isodisomy in twins provide further evidence that the X chromosomes is not involved in Rett syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Migeon, B.R.; Dunn, M.A.; Schmeckpeper, B.J.; Naidu, S. [Johns Hophins Univ., Baltimore, MD (United States); Thomas, G. [Johns Hopkins Univ., Baltimore, MD (United States)]|[Kennedy-Kreiger Institute, Baltimore, MD (United States)

    1995-03-01

    Rett syndrome (RS), a progressive encephalopathy with onset in infancy, has been attributed to an X-linked mutation, mainly on the basis of its occurrence almost exclusively in females and its concordance in female MZ twins. The underlying mechanisms proposed are an X-linked dominant mutation with male lethality, uniparental disomy of the X chromosome, and/or some disturbance in the process of X inactivation leading to unequal distribution of cells expressing maternal or paternal alleles (referred to as a {open_quotes}nonrandom{close_quotes} or {open_quotes}skewed {close_quotes} inactivation). To determine if the X chromosome is in fact involved in RS, we studied a group of affected females including three pairs of MZ twins, two concordant for RS and one uniquely discordant for RS. Analysis of X-inactivation patterns confirms the frequent nonrandom X inactivation previously observed in MZ twins but indicates that this is independent of RS. Analysis of 29 RS females reveals not one instance of uniparental X disomy, extending the observations previously reported. Therefore, our findings contribute no support for the hypothesis that RS is an X-linked disorder. Furthermore, the concordant phenotype in most MZ females twins with RS, which has not been observed in female twins with known X-linked mutations, argues against an X mutation. 41 refs., 2 figs.

  13. Fingerprint recognition with identical twin fingerprints.

    Directory of Open Access Journals (Sweden)

    Xunqiang Tao

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

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

    Science.gov (United States)

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

    2014-02-01

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

  15. 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…

  16. Einstein's Clocks and Langevin's Twins

    CERN Document Server

    Weinstein, Galina

    2012-01-01

    In 1905 Einstein presented the Clock Paradox and in 1911 Paul Langevin expanded Einstein's result to human observers, the "Twin Paradox." I will explain the crucial difference between Einstein and Langevin. Einstein did not present the so-called "Twin Paradox." Later Einstein continued to speak about the clock paradox. Einstein might not have been interested in the question: what happens to the observers themselves. The reason for this could be the following; Einstein dealt with measurement procedures, clocks and measuring rods. Einstein's observers were measuring time with these clocks and measuring rods. Einstein might not have been interested in so-called biology of the observers, whether these observers were getting older, younger, or whether they have gone any other changes; these changes appeared to be out of the scope of his "Principle of relativity" or kinematics. The processes and changes occurring within observers seemed to be good for philosophical discussions. Later writers criticized Einstein's c...

  17. Identical twins in forensic genetics

    DEFF Research Database (Denmark)

    Tvedebrink, Torben; Morling, Niels

    2015-01-01

    The increase in the number of forensic genetic loci used for identification purposes results in infinitesimal random match probabilities. These probabilities are computed under assumptions made for rather simple population genetic models. Often, the forensic expert reports likelihood ratios, where...... published results accounting for close familial relationships. However, we revisit the discussion to increase the awareness among forensic genetic practitioners and include new information on medical and societal factors to assess the risk of not considering a monozygotic twin as the true perpetrator...

  18. Geographic Tongue in Monozygotic Twins

    OpenAIRE

    Shekhar M, Guna

    2014-01-01

    This article discusses a case of 5-year-old girl monozygotic twins who were suffering from geographic tongue (GT), a benign inflammatory disorder of the tongue which is characterized by circinate, irregular erythematous lesions on the dorsum and lateral borders of the tongue caused by loss of filiform papillae of the tongue epithelium. Whilst geographic tongue is a common entity, reports on this condition are uncommon in the literature. To best of our knowledge, this is the first report which...

  19. Thrombosis of anastomoses may affect the staging sequence of twin-twin transfusion syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Wijngaard, Jeroen P H M van den; Gemert, Martin J C van [Laser Center, Academic Medical Center-University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam (Netherlands); Ross, Michael G [Department of Obstetrics and Gynecology, Harbor-UCLA School of Medicine, Torrance, CA 90502 (United States)], E-mail: j.p.vandenwijngaard@amc.uva.nl

    2008-03-07

    Twin-twin transfusion syndrome (TTTS) is a severe complication of monozygotic (identical) twins, which share one single monochorionic placenta. It is caused by placental anastomoses which link the two fetoplacental circulations of the twins and allow a chronic net inter-twin transfusion to develop between the fetuses. Clinical presentation of TTTS manifestations has been classified into five different stages. In this paper, we used our computational model of TTTS and examined the possible differences between chronic and rapidly increasing inter-twin transfusion in the simulated TTTS staging sequence. Our results suggest that rapid alterations in the net inter-twin transfusion, e.g. due to thrombosis of placental anastomoses, may produce a different staging sequence than in TTTS caused by chronic inter-twin transfusion. These results may aid an improved knowledge of TTTS pathophysiology under conditions of a rapidly changing cardiovascular function, and contribute to the planning of optimal intervention under such circumstances. (note)

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

    Science.gov (United States)

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

    2009-10-01

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

  1. The TWINS Science Data System after the launch of TWINS 1

    Science.gov (United States)

    Goldstein, J.; Valek, P.; Skoug, R.; Delapp, D.; Redfern, J.; Carruth, B.; McComas, D.

    2007-05-01

    The Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) 1 satellite is in orbit and science data are expected to commence in the near future. TWINS-1 comprises half of the TWINS stereoscopic neutral atom imaging system that will advance our knowledge of the Earth's ring current. To support the expected data return, we have developed a Science Data System (SDS) for the TWINS mission. The TWINS SDS is an IDL- and Java- driven data interface that operates primarily via a web browser, and has as its spine an SQL-queryable database. Through this interface, TWINS science data will be provided to the TWINS team, the space science community, and the public. In this paper we present the current and future capabilities of the TWINS SDS, as well as how the SDS fits into virtual observatory infrastructure.

  2. 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...... and their families as well as a test of the fetal origins hypothesis that states that fetal growth restriction has long-term health consequences. Secondly, we summarise some of the most important register-based ''classical twin studies'', e.g. heritability studies on lifespan and exceptional longevity. Finally, we...

  3. Twin delivery: method, timing and conduct.

    Science.gov (United States)

    Barrett, Jon F R

    2014-02-01

    The incidence of twin pregnancy has increased worldwide over the past 10 years, largely as a consequence of the assisted reproductive technologies. Issues such as intrapartum monitoring and operative interventions, especially relating to the second twin, provide a unique challenge in labour and delivery. Epidemiological and cohort data suggest that twins have a three-fold higher mortality rate than singletons, and that the second twin might have a better outcome if delivered by lower segment caesarean section. The recently completed Twin Birth Study has found that planned vaginal lower segment caesarean section is not advantageous to the fetus. In the light of this large randomised-controlled trial, vaginal delivery if twin A presents by the vertex is recommended as long as guidelines for the conduct of such delivery are followed.

  4. (120) and (122-bar) monazite deformation twins

    Energy Technology Data Exchange (ETDEWEB)

    Hay, R.S

    2003-10-20

    Unusual features of (120) and (122-bar) deformation twins in monazite (monoclinic LaPO{sub 4}) are described and analyzed. These features are kinks and other irregularities in (120) twins, and V-shaped indentations on (120) and (122-bar) twin planes. Twinning shear analysis suggests that the kinks are a type II deformation twin mode with shear direction ({eta}{sub 1}) of [21-bar0]. This complements previous analysis based on atom shuffling considerations. Shear strain compatibility requires extensive plastic deformation in the kink. The V-shaped indentations may be analogous to similar structures in b.c.c metal deformation twins. Deformation mechanisms that may be associated with these structures are discussed.

  5. Fullerton Virtual Twin Study: an update.

    Science.gov (United States)

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

    2013-02-01

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

  6. Twinning of Polymer Crystals Suppressed by Entropy

    Directory of Open Access Journals (Sweden)

    Nikos Ch. Karayiannis

    2014-09-01

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

  7. Prevention of preterm delivery in twin pregnancy

    DEFF Research Database (Denmark)

    Rode, Line; Tabor, Ann

    2014-01-01

    The incidence of twin gestation has increased markedly over the past decades, mostly because of increased use of assisted reproductive technologies. Twin pregnancies are at increased risk of preterm delivery (i.e. birth before 37 weeks of gestation). Multiple gestations therefore account for 2......, it is mandatory to evaluate the proposed treatments in randomised trials of multiple gestations. In this chapter, we describe the results of trials to prevent preterm delivery in twin pregnancies....

  8. Idiopathic intracranial hypertension in female homozygous twins.

    OpenAIRE

    Fujiwara, S; Sawamura, Y; Kato, T.; Abe, H.; Katusima, H

    1997-01-01

    The authors report on female homozygous twins with idiopathic intracranial hypertension. At the age of 12 years, both twins simultaneously developed visual disturbances with photophobia. At the age of 19 years, an ophthalmological examination disclosed papilloedema in both their eyes. At the age of 22 years, a lumbar puncture showed raised CSF pressure over (200 mm H2O) in both twins. Their neurological and radiological examinations were extremely similar; both of them had severely impaired v...

  9. Anaesthesia for the separation of conjoined twins

    Directory of Open Access Journals (Sweden)

    Jaya Lalwani

    2011-01-01

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

  10. Culture systems: embryo culture and monozygotic twinning.

    Science.gov (United States)

    Sparks, Amy E

    2012-01-01

    The incidence of monozygotic twinning in pregnancies achieved with assisted reproductive technologies (ART) is significantly higher than spontaneously conceived pregnancies. The factors associated with ART that predispose the embryos to splitting are not well-characterized. Assisted hatching and extended embryo culture are two ART laboratory methods that have been risk factors for monozygotic twinning. The methods and strategies that may be employed to avoid monozygotic twinning are discussed in this chapter.

  11. The Solar Twin Planet Search II. A Jupiter twin around a solar twin

    CERN Document Server

    Bedell, M; Bean, J L; Ramirez, I; Asplund, M; Alves-Brito, A; Casagrande, L; Dreizler, S; Monroe, T; Spina, L; Maia, M Tucci

    2015-01-01

    Through our HARPS radial velocity survey for planets around solar twin stars, we have identified a promising Jupiter twin candidate around the star HIP11915. We characterize this Keplerian signal and investigate its potential origins in stellar activity. Our analysis indicates that HIP11915 hosts a Jupiter-mass planet with a 3600-day orbital period and low eccentricity. Although we cannot definitively rule out an activity cycle interpretation, we find that a planet interpretation is more likely based on a joint analysis of RV and activity index data. The challenges of long-period radial velocity signals addressed in this paper are critical for the ongoing discovery of Jupiter-like exoplanets. If planetary in nature, the signal investigated here represents a very close analog to the solar system in terms of both Sun-like host star and Jupiter-like planet.

  12. Rapid onset of severe twin-twin transfusion syndrome caused by placental venous thrombosis

    NARCIS (Netherlands)

    Nikkels, PGJ; van Gemert, MJC; Sollie-Szarynska, KM; Molendijk, H; Timmer, B; Machin, GA

    2002-01-01

    We report a case of rapid onset of severe twin-twin transfusion syndrome (TTTS) at 25 weeks gestation in a monochorionic twin pregnancy that was uneventful before that time. Thrombosis of a main venous branch draining several arteriovenous (AV) anastomoses to the donor changed the previous hemodynam

  13. Atomistic deformation mechanisms in twinned copper nanospheres.

    Science.gov (United States)

    Bian, Jianjun; Niu, Xinrui; Zhang, Hao; Wang, Gangfeng

    2014-01-01

    In the present study, we perform molecular dynamic simulations to investigate the compression response and atomistic deformation mechanisms of twinned nanospheres. The relationship between load and compression depth is calculated for various twin spacing and loading directions. Then, the overall elastic properties and the underlying plastic deformation mechanisms are illuminated. Twin boundaries (TBs) act as obstacles to dislocation motion and lead to strengthening. As the loading direction varies, the plastic deformation transfers from dislocations intersecting with TBs, slipping parallel to TBs, and then to being restrained by TBs. The strengthening of TBs depends strongly on the twin spacing.

  14. Invasive treatment in complicated monochorionic twin pregnancies

    DEFF Research Database (Denmark)

    Sundberg, Karin; Søgaard, Kirsten; Jensen, Lisa Neerup;

    2012-01-01

    Objective. Monochorionic twin pregnancies are associated with increased risk of severe complications. Umbilical cord occlusion (UCO) and fetoscopic selective laser coagulation (FSLC) are used as invasive treatment. The study aim was to document treatment indications and pregnancy outcome where UCO...... and FSLC were used for treating fetal discrepancies and twin-to-twin transfusion syndrome (TTTS). Design. Cohort study of all consecutively treated monochorionic twin pregnancies 2004-2010. Setting. Tertiary care center. Population. One hundred and twenty pregnancies treated by FSLC (55) or UCO (65...

  15. Vascular distribution patterns in monochorionic twin placentas.

    Science.gov (United States)

    De Paepe, M E; DeKoninck, P; Friedman, R M

    2005-07-01

    Several recent publications have focused on the association between the occurrence of twin-to-twin transfusion syndrome (TTTS) in diamniotic-monochorionic twins and the presence of a number of selected anatomic placental characteristics (distribution of vascular territory, cord insertion, type and number of inter-twin anastomoses). In contrast, the potential importance of the vascular distribution patterns of the individual twins remains to be elucidated. Based on its gross architectural distribution pattern, chorionic vasculature is traditionally described as disperse, magistral or mixed. The aim of this study was (1) to determine the relative prevalence of these vascular distribution patterns in monochorionic twin placentas, and (2) to correlate these patterns with the presence of TTTS and known anatomic placental features linked to TTTS. The placentas of 89 consecutive diamniotic-monochorionic twins (15 with TTTS, 74 without TTTS), examined at Women and Infants Hospital, were studied. Disperse vascular patterns were seen in 53% of twins, and magistral or mixed patterns in 47%. The prevalence of magistral/mixed vascular patterns was significantly higher in TTTS gestations than in non-TTTS gestations (60% versus 44%, Ppatterns and marginal/velamentous cord insertion, low number of inter-twin anastomoses, and uneven distribution of the vascular territories. These findings suggest that the magistral/mixed vascular distribution pattern may represent an important placental architectural feature contributing to the complex pathophysiology of TTTS.

  16. Problem in twin pregnancy: Findings of prenatal sonography and autopsy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Ah; Cho, Jeong Yeon; Song, Mi Jin; Min, Jee Yeon; Lee, Young Ho; Lee, Hak Jong; Chun, Yi Kyeong; Kim, Yee Jeong; Hong, Sung Ran [Samsung Cheil Hospital, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2001-12-15

    Multifetal gestations are high risk pregnancies with higher perinatal morbidity and mortality. Multifetal gestations are subject to unique complications including conjoined twins, twin-to-twin transfusion syndrome (TTTS), acardiac twins, twin embization of co-twin demise and heterotopic pregnancies. Prenatal sonographic diagnosis of types and complications of multifetal gestations is important for antenatal care and prediction of fetal outcome. This study was performed to present the prenatal ultrasonographic findings and pathologic findings of the unique complications of twin pregnancy. Acardia is a lethal anomaly occurring in 1% of monozygotic twin. The acardiac twin has a parasitic existence and depends on the donor (pump) twin for its blood supply via placental anastomoses and retrograde perfusion of umbilical cord. This twin reversed arterial perfusion (TRAP) sequence is a most extreme manifestation on the TTTS. Doppler verification reversed flow in umbilical cord of the acardiac twin confirms the diagnosis.

  17. Being Pregnant with Twins, Triplets and Other Multiples

    Science.gov (United States)

    ... twins, triplets and other multiples Being pregnant with twins, triplets and other multiples E-mail to a ... embryos that grow into two or more babies. Twins are called identical when one fertilized egg splits ...

  18. Quantum Discord Dynamics of Two Atoms Interacting with Two Quantized Field Modes through a Raman Interaction with Phase Decoherence

    Institute of Scientific and Technical Information of China (English)

    QIAN Yi; XU Jing-Bo

    2011-01-01

    We investigate the quantum discord dynamics of two effective two-level atoms independently interacting with two quantized field modes through a Raman interaction in the presence of phase decoherence.The influence of the phase decoherence and detuning on the evolution of the quantum discord and entanglement between two atoms is discussed.It is found that the quantum discord is more robust than the entanglement under the phase decoherence,and the amount of discord and entanglement between two atoms can be increased by adjusting the detuning.

  19. Phase Field Modeling of Twinning in Indentation of Transparent Crystals

    Science.gov (United States)

    2011-09-01

    twin boundaries . Equilibrium configurations of deformed and twinned crystals are attained via direct energy minimization. The theory is framed in the...phases: (i) the original crystal (the parent) and (ii) the twin. Interfaces between phases are twin boundaries . Order parameter η generally exhibits the...following values: η(X, •) = 0∀X ∈ parent, = 1∀X ∈ twin, ∈ (0, 1)∀X ∈ twin boundaries . (1) In linear elasticity, kinematic field variables are

  20. Weak phonon scattering effect of twin boundaries on thermal transmission.

    Science.gov (United States)

    Dong, Huicong; Xiao, Jianwei; Melnik, Roderick; Wen, Bin

    2016-01-29

    To study the effect of twin boundaries on thermal transmission, thermal conductivities of twinned diamond with different twin thicknesses have been studied by NEMD simulation. Results indicate that twin boundaries show a weak phonon scattering effect on thermal transmission, which is only caused by the additional twin boundaries' thermal resistance. Moreover, according to phonon kinetic theory, this weak phonon scattering effect of twin boundaries is mainly caused by a slightly reduced average group velocity.

  1. Weak phonon scattering effect of twin boundaries on thermal transmission

    OpenAIRE

    Huicong Dong; Jianwei Xiao; Roderick Melnik; Bin Wen

    2016-01-01

    To study the effect of twin boundaries on thermal transmission, thermal conductivities of twinned diamond with different twin thicknesses have been studied by NEMD simulation. Results indicate that twin boundaries show a weak phonon scattering effect on thermal transmission, which is only caused by the additional twin boundaries’ thermal resistance. Moreover, according to phonon kinetic theory, this weak phonon scattering effect of twin boundaries is mainly caused by a slightly reduced averag...

  2. [Social development of twins: the need for intervention to avoid adverse effects of twin language].

    Science.gov (United States)

    Hayashi, Chisato; Hayakawa, Kazuo; Maeda, Chiho; Nishihara, Reiko; Onoi, Miyuki

    2008-10-01

    Social competence is one of the most important accomplishments of human development, and this skill in human relationships is learned through communication. Therefore, it is considered that delays in language development could be a barrier to building human relationships and social competence. Although it is well known that there are delays in language development in twins compared with that of singletons, little is known about how these linguistic delays affect the development of social competence. Because twin language is a language that is unique to each pair of twins and cannot be understood by either their mother or others, it may be assumed that the social competence of twins who have a twin language is less than that of twins who don't have a twin language. Therefore, in this prospective longitudinal study we also investigated the relationship between twin language and social competence. A mailed questionnaire survey was conducted in 958 mothers as a follow-up of a study conducted in 2004. As a result, 522 respondents returned the questionnaire (53.9%). In this study, we used only 256 twins aged 6- 12-years-old (school-age children) for analysis, excluding those with missing values. Multiple logistic regression analysis was employed. In the second child of twins, a low birth weight, the appearance of twin language and gestosis of the mother were positively related with social unbalance (OR = 1.846, 2.022 and 1.903). On the other hand, with the first child, however, there was no such link. The present results indicate that twin language might influence social competence in school-age children. It has been believed that linguistic intervention is unnecessary, because most twin language disappears spontaneously. However, early intervention, for example linguistic assistance by public health nurses or psychologists and early enrollment in a preschool may be necessary for twins with a twin language, to avoid adverse consequences in social competence at school-age.

  3. Quantum discord and quantum phase transition in the XXZ spin chain with three-site interaction

    Science.gov (United States)

    Yang, Jing; Cong, Mei-Yan; Huang, Yan-Xia

    2016-12-01

    Pairwise quantum discord (QD) and entanglement of the three-qubit XXZ Heisenberg spin chain with two types of three-site interactions and an external magnetic field are investigated. Our study found that both entanglement and quantum discord could detect the quantum critical phenomena of this model. We were able to obtain a nonzero value of quantum discord even at high temperature with the increase of XZX+YZY or XZY-YZX three-site interaction, however, the cooperative effect of XZX+YZY and XZY-YZX interactions is more ideal. Furthermore, in contrast to XZY-YZX and XZX+YZY interactions, the cooperative effect of XZX+YZY and XZY-YZX three-site interactions is more efficient to enhance the maximum value of quantum discord. Likewise, the cooperative effect of XZX+YZY and XZY-YZX interactions is the most optimal to increase the range of magnetic field or anisotropy parameter where quantum discord maintains the maximum value.

  4. Subjects with Discordant Airways Obstruction: Lost between Spirometric Definitions of COPD

    Directory of Open Access Journals (Sweden)

    Bernd Lamprecht

    2011-01-01

    Full Text Available Background. Since the FEV1/FVC ratio declines with age, using the fixed ratio of 0.70 leads to overdiagnosis of COPD in older populations and underdiagnosis among young adults. Objective. To evaluate whether discordant obstructive cases (FEV1/FVC < 0.70 but ≥LLN are a healthy population or have clinical features that would place them at increased risk. Methods. We used post-bronchodilator spirometry data from the population-based Austrian Burden of Obstructive Lung Disease (BOLD study. Those with post-bronchodilator FEV1/FVC ratio discordant obstructive cases. Results. Discordant obstructive cases were more likely to be older, male and never-smokers. Additionally they had less respiratory symptoms and less severe impairment of FEV1. However, discordant obstructive cases reported significantly more often a diagnosis of heart disease than subjects with normal lung function (27.2% vs 7.3%, P=.015. Conclusion. The clinical profile of discordant obstructive cases includes potentially important comorbid disease.

  5. Characterization of Sera with Discordant Results from Reverse Sequence Screening for Syphilis

    Directory of Open Access Journals (Sweden)

    Kyunghoon Lee

    2013-01-01

    Full Text Available Reverse sequence screening for syphilis (RSSS (screening with treponemal tests, followed by confirmation with nontreponemal tests has been increasingly adopted. CDC recommends confirmation of discordant results (reactive EIA/CIA and nonreactive nontreponemal test with Treponema pallidum particle agglutination assay (TP-PA. We characterized sera with discordant results from RSSS with Architect Syphilis TP CIA. Among 15,713 screening tests using Architect Syphilis TP at Seoul National University Gangnam Center between October 2010 and May 2011, 260 (1.7% showed reactive results. Rapid plasma reagin (RPR and TP-PA were performed on 153 available sera among them. On sera with discordant results between Architect Syphilis TP and TP-PA, INNO-LIA Syphilis Score and FTA-ABS were performed. Among 153 sera, RPR was nonreactive in 126 (82.4%. Among them, TP-PA was positive in 103 (81.7%, indeterminate (± in 7 (5.6%, and negative in 16 (12.7%. Out of 16 CIA(+/RPR(−/TP-PA(− sera, INNO-LIA Syphilis Score and/or FTA-ABS were negative on 14 sera. Out of 7 CIA(+/RPR(−/TP-PA(± sera, INNO-LIA Syphilis Score and FTA-ABS were positive/reactive in 6 sera. RSSS with confirmation by TP-PA on sera with discordant results between Architect Syphilis TP and RPR effectively delineated those discordant results and could be successfully adopted for routine checkup for syphilis.

  6. Haemodynamic resistance model of monochorionic twin pregnancies complicated by acardiac twinning

    Energy Technology Data Exchange (ETDEWEB)

    Umur, Asli [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam(Netherlands); Gemert, Martin J C van [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Wijngaard, Jeroen P H M van den [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Ross, Michael G [Department of Obstetrics and Gynecology, Harbor University of California-Los Angeles Medical Center, Torrence, CA 9050 (United States); Nikkels, Peter G J [Department of Pathology, University Medical Center, Utrecht (Netherlands)

    2004-07-21

    An acardiac twin is a severely malformed monochorionic twin fetus that lacks most organs, particularly a heart. It grows during pregnancy, because it is perfused by its developmentally normal co-twin (called the pump twin) via a set of placental arterioarterial and venovenous anastomoses. The pump twin dies intrauterine or neonatally in about 50% of the cases due to congestive heart failure, polyhydramnios and prematurity. Because the pathophysiology of this pregnancy is currently incompletely understood, we modified our previous haemodynamic model of monochorionic twins connected by placental vascular anastomoses to include the analysis of acardiac twin pregnancies. We incorporated the fetoplacental circulation as a resistance circuit and used the fetal umbilical flow that perfuses the body to define fetal growth, rather than the placental flow as done previously. Using this modified model, we predicted that the pump twin has excess blood volume and increased mean arterial blood pressure compared to those in the acardiac twin. Placental perfusion of the acardiac twin is significantly reduced compared to normal, as a consequence of an increased venous pressure, possibly implying reduced acardiac placental growth. In conclusion, the haemodynamic analysis may contribute to an increased knowledge of the pathophysiologic consequences of an acardiac body mass for the pump twin. (note)

  7. Twin-Foucault imaging method

    Science.gov (United States)

    Harada, Ken

    2012-02-01

    A method of Lorentz electron microscopy, which enables observation two Foucault images simultaneously by using an electron biprism instead of an objective aperture, was developed. The electron biprism is installed between two electron beams deflected by 180° magnetic domains. Potential applied to the biprism deflects the two electron beams further, and two Foucault images with reversed contrast are then obtained in one visual field. The twin Foucault images are able to extract the magnetic domain structures and to reconstruct an ordinary electron micrograph. The developed Foucault method was demonstrated with a 180° domain structure of manganite La0.825Sr0.175MnO3.

  8. Twin-Screw Extruders in Ceramic Extrusion

    Science.gov (United States)

    Wiedmann, Werner; Hölzel, Maria

    The machines mainly used for compounding plastics, chemicals and food are co-rotating, closely intermeshing twin-screw extruders. Some 30 000 such extruders are in use worldwide, about 1/3 are ZSKs from Coperion Werner & Pfleiderer, Stuttgart. In the chemical industry more and more batch mixers are being replaced by continuous twin-screw kneaders.

  9. Cord entanglement in monoamniotic twin pregnancies

    DEFF Research Database (Denmark)

    Lyndrup, J; Schouenborg, Lars Øland

    1987-01-01

    Monoamniotic twin pregnancy involves a heavy risk of fatal umbilical cord entanglement. Two cases are reported. In the first case, both twins were found dead in the 36th week, and the monoamnionicity was recognized at birth. In the second case, the monoamnionicity was discovered during...

  10. Optimal nutrition for improved twin pregnancy outcome.

    Science.gov (United States)

    Goodnight, William; Newman, Roger

    2009-11-01

    Twin pregnancies contribute a disproportionate degree to perinatal morbidity, partly because of increased risks of low birth weight and prematurity. Although the cause of the morbidity is multifactorial, attention to twin-specific maternal nutrition may be beneficial in achieving optimal fetal growth and birth weight. Achievement of body mass index (BMI)-specific weight gain goals, micronutrient and macronutrient supplementation specific to the physiology of twin gestations, and carbohydrate-controlled diets are recommended for optimal twin growth and pregnancy outcomes. The daily recommended caloric intake for normal-BMI women with twins is 40-45 kcal/kg each day, and iron, folate, calcium, magnesium, and zinc supplementation is recommended beyond a usual prenatal vitamin. Daily supplementation of docosahexaenoic acid and vitamin D should also be considered. Multiple gestation-specific prenatal care settings with a focus on nutritional interventions improve birth weight and length of gestation and should be considered for the care of women carrying multiples. Antepartum lactation consultation can also improve the rate of postpartum breastfeeding in twin pregnancies. Twin gestation-specific nutritional interventions seem effective in improving the outcome of these pregnancies and should be emphasized in the antepartum care of multiple gestations. This review examines the available evidence and offers recommendations for twin pregnancy-specific nutritional interventions.

  11. Fetal behavior in normal dichorionic twin pregnancy

    NARCIS (Netherlands)

    Mulder, E. J. H.; Derks, J. B.; de Laat, M. W. M.; Visser, G. H. A.

    2012-01-01

    Objectives: A prospective study was performed to compare fetal behavioral development in healthy dichorionic twins and singletons, and identify twin intra-pair associations (synchrony) of fetal movements and rest-activity cycles using different criteria to define synchrony. Subjects and methods: Twe

  12. Fatique life and twinning in alphazirconium

    DEFF Research Database (Denmark)

    Warren, M.R.; Beevers, C.J.

    1970-01-01

    stress for {11−21} twinning of ~0.5 kg mm−2 in zirconium containing 0.003 wt pct O. During observations confined to internal grains it was found that increasing grain size and decreasing oxygen content favored the formation of fatigue damage in association with these {11−21} twins. In external grains...

  13. A Danish Twin Study of Schizophrenia Liability

    DEFF Research Database (Denmark)

    Kläning, Ulla; Trumbetta, Susan L; Gottesman, Irving I

    2016-01-01

    We studied schizophrenia liability in a Danish population-based sample of 44 twin pairs (13 MZ, 31 DZ, SS plus OS) in order to replicate previous twin study findings using contemporary diagnostic criteria, to examine genetic liability shared between schizophrenia and other disorders, and to explo...

  14. The relationship between Hippocampal asymmetry and working memory processing in combat-related PTSD – a monozygotic twin study

    Directory of Open Access Journals (Sweden)

    Hall Timothy

    2012-12-01

    Full Text Available Abstract Background PTSD is associated with reduction in hippocampal volume and abnormalities in hippocampal function. Hippocampal asymmetry has received less attention, but potentially could indicate lateralised differences in vulnerability to trauma. The P300 event-related potential component reflects the immediate processing of significant environmental stimuli and has generators in several brain regions including the hippocampus. P300 amplitude is generally reduced in people with PTSD. Methods Our study examined hippocampal volume asymmetry and the relationship between hippocampal asymmetry and P300 amplitude in male monozygotic twins discordant for Vietnam combat exposure. Lateralised hippocampal volume and P300 data were obtained from 70 male participants, of whom 12 had PTSD. We were able to compare (1 combat veterans with current PTSD; (2 their non-combat-exposed co-twins; (3 combat veterans without current PTSD and (4 their non-combat-exposed co-twins. Results There were no significant differences between groups in hippocampal asymmetry. There were no group differences in performance of an auditory oddball target detection task or in P300 amplitude. There was a significant positive correlation between P300 amplitude and the magnitude of hippocampal asymmetry in participants with PTSD. Conclusions These findings suggest that greater hippocampal asymmetry in PTSD is associated with a need to allocate more attentional resources when processing significant environmental stimuli.

  15. Depressive symptomatology in child and adolescent twins with attention-deficit hyperactivity disorder and/or developmental coordination disorder.

    Science.gov (United States)

    Piek, Jan P; Rigoli, Daniela; Pearsall-Jones, Jillian G; Martin, Neilson C; Hay, David A; Bennett, Kellie S; Levy, Florence

    2007-08-01

    Previous research has demonstrated a link between attention-deficit/hyperactivity disorder (ADHD), developmental coordination disorder (DCD), and depression. The present study utilized a monozygotic (MZ) differences design to investigate differences in depressive symptomatology between MZ twins discordant for ADHD or DCD. This extends previous research as it controls for genetic effects and shared environmental influences and enables the investigation of nonshared environmental influences. In addition, children and adolescents with comorbid ADHD and DCD were compared on their level of depressive symptomatology to those with ADHD only, DCD only, and no ADHD or DCD. The parent-rated Strengths and Weaknesses of ADHD Symptoms and Normal Behavior, Developmental Coordination Disorder Questionnaire, and Sad Affect Scale were used to assess ADHD, DCD, and depressive symptomatology respectively. The results revealed higher levels of depressive symptomatology in MZ twins with ADHD or DCD compared to their nonaffected co-twins. In addition, children and adolescents with comorbid ADHD and DCD demonstrated higher levels of depressive symptomatology compared to those with ADHD only, DCD only, and no ADHD or DCD. The implications of these findings are discussed with emphasis on understanding and recognizing the relationship between ADHD, DCD, and depression in the assessment and intervention for children and adolescents with these disorders.

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

    Directory of Open Access Journals (Sweden)

    Andrea Ganna

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

  17. Twins in Ancient Greece: a synopsis.

    Science.gov (United States)

    Malamitsi-Puchner, Ariadne

    2016-01-01

    This brief outline associates twins with several aspects of life in Ancient Greece. In Greek mythology twins caused ambivalent reactions and were believed to have ambivalent feelings for each other. Very often, they were viewed as the representatives of the dualistic nature of the universe. Heteropaternal superfecundation, which dominates in ancient myths, explains on one hand, the god-like qualities and, on the other hand, the mortal nature of many twins. An assumption is presented that legends referring to twins might reflect the territorial expansions of Ancient Greeks in Northern Mediterranean, around the Black Sea, in Asia Minor, as well as North East Africa. In conclusion, in Greek antiquity, twins have been used as transitional figures between myth and reality.

  18. Cosmological Signals of a Mirror Twin Higgs

    CERN Document Server

    Craig, Nathaniel; Trott, Timothy

    2016-01-01

    We investigate the cosmology of the minimal model of neutral naturalness, the mirror Twin Higgs. The softly-broken mirror symmetry relating the Standard Model to its twin counterpart leads to significant dark radiation in tension with BBN and CMB observations. We quantify this tension and illustrate how it can be mitigated in several simple scenarios that alter the relative energy densities of the two sectors while respecting the softly-broken mirror symmetry. In particular, we consider both the out-of-equilibrium decay of a new scalar as well as reheating in a toy model of twinned inflation, Twinflation. In both cases the dilution of energy density in the twin sector does not merely reconcile the existence of a mirror Twin Higgs with cosmological constraints, but predicts contributions to cosmological observables that may be probed in current and future CMB experiments. This raises the prospect of discovering evidence of neutral naturalness through cosmology rather than colliders.

  19. '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.

    Science.gov (United States)

    Segal, Nancy L

    2017-03-28

    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.

  20. On the quantum discord of two-qubit X-states

    CERN Document Server

    Chen, Qing; Yu, Sixia; Yi, X X; Oh, C H

    2011-01-01

    Quantum discord provides a measure for quantifying quantum correlations beyond entanglement and is very hard to compute even for two-qubit states because of the minimization over all possible measurements. Recently a simple algorithm to evaluate the quantum discord for two-qubit X-states is proposed by Ali, Rau and Alber [Phys. Rev. A 81, 042105 (2010)] with minimization taken over only a few cases. Here we shall at first identify a class of X-states, whose quantum discord can be evaluated analytically without any minimization, for which their algorithm is valid, and also identify a family of X-states for which their algorithm fails. And then we demonstrate that this special family of X-states provides furthermore an explicit example for the inequivalence between the minimization over positive operator-valued measures and that over von Neumann measurements.

  1. Discordance in couples' reporting of courtship stages: Implications for measurement and marital quality.

    Science.gov (United States)

    Halpern-Meekin, Sarah; Tach, Laura

    2013-07-01

    The symbolism of rituals creates a shared understanding of events among group members. In the context of romantic relationships, a shared understanding of relationship status transitions may be associated with greater commitment and higher quality relationships. We argue that couples with differing retrospective accounts of their premarital courtship may not have had clear discussions or rituals marking relationship turning points. We test the association between discordance in couples' reports of premarital courtship stages and marital quality using data from married couples in a national online survey (n=1504). We find that couple discordance is common, particularly among former premarital cohabitors and for the less institutionalized relationship stages of dating and stayovers, and is associated with lower marital quality. Implications for relationship measurement and the meaning of couple discordance are discussed.

  2. Reconceptulizing Language Discordance: Meanings and Experiences of Language Barriers in the U.S. and Taiwan.

    Science.gov (United States)

    Hsieh, Elaine

    2017-02-24

    Individuals with language barriers may face challenges unique to a host society. By examining and comparing the sociocultural conditions that can result in providers and patients not sharing the same language in the United States and in Taiwan, I argue that (a) language discordance is a social phenomenon that may entail diverging meanings and experiences in different countries; (b) language-discordant patients may not share similar experiences even if they are in the same country; and (c) disparities in language concordance may be confounded with other disparities and cultural particulars that are unique to a host society. In addition, because English is a dominant language in medicine, language-discordant patients' quality of care in Taiwan can be moderated by their fluency in English.

  3. Effect of excess noise on continuous variable entanglement sudden death and Gaussian quantum discord

    Institute of Scientific and Technical Information of China (English)

    Su Xiao-Long

    2013-01-01

    A symmetric two-mode Gaussian entangled state is used to investigate the effect of excess noise on entanglement sudden death and Gaussian quantum discord with continuous variables.The results show that the excess noise in the channel can lead to entanglement sudden death of a symmetric two-mode Gaussian entangled state,while Gaussian quantum discord never vanishes.As a practical application,the security of a quantum key distribution (QKD) scheme based on a symmetric two-mode Gaussian entangled state against collective Gaussian attacks is analyzed.The calculation results show that the secret key cannot be distilled when entanglement vanishes and only quantum discord exists in such a QKD scheme.

  4. Robustness measure of hybrid intra-particle entanglement, discord, and classical correlation with initial Werner state

    Science.gov (United States)

    Saha, P.; Sarkar, D.

    2016-02-01

    Quantum information processing is largely dependent on the robustness of non-classical correlations, such as entanglement and quantum discord. However, all the realistic quantum systems are thermodynamically open and lose their coherence with time through environmental interaction. The time evolution of quantum entanglement, discord, and the respective classical correlation for a single, spin-1/2 particle under spin and energy degrees of freedom, with an initial Werner state, has been investigated in the present study. The present intra-particle system is considered to be easier to produce than its inter-particle counterpart. Experimentally, this type of system may be realized in the well-known Penning trap. The most stable correlation was identified through maximization of a system-specific global objective function. Quantum discord was found to be the most stable, followed by the classical correlation. Moreover, all the correlations were observed to attain highest robustness under initial Bell state, with minimum possible dephasing and decoherence parameters.

  5. 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.

    Science.gov (United States)

    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.

  6. Tomographic causal analysis of two-qubit states and tomographic discord

    Energy Technology Data Exchange (ETDEWEB)

    Kiktenko, Evgeny [Bauman Moscow State Technical University, 2nd Baumanskaya St., 5, Moscow 105005 (Russian Federation); Geoelectromagnetic Research Center of Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, PO Box 30, Troitsk, Moscow Region 142190 (Russian Federation); Fedorov, Aleksey, E-mail: akf@rqc.ru [Bauman Moscow State Technical University, 2nd Baumanskaya St., 5, Moscow 105005 (Russian Federation); Russian Quantum Center, Novaya St. 100, Skolkovo, Moscow 143025 (Russian Federation)

    2014-05-01

    We study a behavior of two-qubit states subject to tomographic measurement. In this Letter we propose a novel approach to definition of asymmetry in quantum bipartite state based on its tomographic Shannon entropies. We consider two types of measurement bases: the first is one that diagonalizes density matrices of subsystems and is used in a definition of tomographic discord, and the second is one that maximizes Shannon mutual information and relates to symmetrical form quantum discord. We show how these approaches relate to each other and then implement them to the different classes of two-qubit states. Consequently, new subclasses of X-states are revealed.

  7. Modelling the influence of amnionicity on the severity of twin-twin transfusion syndrome in monochorionic twin pregnancies

    Energy Technology Data Exchange (ETDEWEB)

    Wijngaard, Jeroen P H M van den [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Umur, Asli [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Ross, Michael G [Department of Obstetrics and Gynecology, Harbor University of California-Los Angeles Medical Center, Torrance, CA 90502 (United States); Gemert, Martin J C van [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands)

    2004-03-21

    Clinical treatment for diamniotic-monochorionic twin-twin transfusion syndrome (TTTS) may include conversion of diamniotic pregnancies to a monoamniotic-monochorionic state by disrupting the amnion septum. We sought to test the underlying hypothesis, i.e. that a monoamniotic state reduces the severity of TTTS. With use of our previously developed mathematical model of two equal fetoplacental circulatory units connected by various sizes and types of placental anastomoses, we compared the haemodynamic and amniotic fluid dynamics of monoamniotic and diamniotic twins that develop TTTS. We used three anastomotic patterns that produce severe, moderate or mild forms of TTTS, respectively, in our diamniotic-monochorionic twin model. Monoamnionicity was modelled by adding the two amniotic fluid volumes and using the volume-averaged amniotic fluid osmolality. The results were as follows: for severe TTTS, small differences develop between diamniotic and monoamniotic donor twins in fetal urine production, swallowed volume, blood volume, blood pressures, net fetofetal transfusion, and blood and amniotic fluid osmolality. However, the circulatory imbalance between the monoamniotic twins deteriorates similar to that of diamniotic twins. The pathophysiological differences tend to disappear for milder TTTS. In conclusion, our model suggests that the uncommon finding of TTTS in monoamniotic twins is not due to the presence of a single amniotic sac. Rather, clinically significant differences in anastomotic patterns and the delayed or lack of identification of manifestations in monoamniotic twins account for the reduced rate of TTTS diagnosis. Based on these results we expect the clinical disruption of the amnion septum in diamniotic-monochorionic TTTS pregnancies to have only minimal benefits. (note)

  8. Generation of Entanglement, Measure of Multipartite Entanglement in Fermionic Systems and Quantum Discord in Bipartite Systems and Heisenberg Chains

    CERN Document Server

    Lari, Behzad

    2011-01-01

    This is a thesis submitted to university of Pune, India, for the Ph.D. degree. This work deals with entanglement production in two qubit, two qutrit and three qubit systems, entanglement in indistinguishable fermionic systems, quantum discord in a Heisenberg chain and geometric measure of quantum discord in an arbitrary state of a bipartite quantum system.

  9. NOTE: Thrombosis of anastomoses may affect the staging sequence of twin twin transfusion syndrome

    Science.gov (United States)

    van den Wijngaard, Jeroen P. H. M.; Ross, Michael G.; van Gemert, Martin J. C.

    2008-03-01

    Twin-twin transfusion syndrome (TTTS) is a severe complication of monozygotic (identical) twins, which share one single monochorionic placenta. It is caused by placental anastomoses which link the two fetoplacental circulations of the twins and allow a chronic net inter-twin transfusion to develop between the fetuses. Clinical presentation of TTTS manifestations has been classified into five different stages. In this paper, we used our computational model of TTTS and examined the possible differences between chronic and rapidly increasing inter-twin transfusion in the simulated TTTS staging sequence. Our results suggest that rapid alterations in the net inter-twin transfusion, e.g. due to thrombosis of placental anastomoses, may produce a different staging sequence than in TTTS caused by chronic inter-twin transfusion. These results may aid an improved knowledge of TTTS pathophysiology under conditions of a rapidly changing cardiovascular function, and contribute to the planning of optimal intervention under such circumstances. Supported in part by the European Community Euro-twin-2-twin project (JPHMvdW) and by the National Institutes of Health, grant HL40899 (MGR).

  10. The Discordance Between HER-2/NEU Expression Assessed by Immunohistochemistry (IHC and Fluorescence in Situ Hybridization (FISH: Is It Important to Detect?

    Directory of Open Access Journals (Sweden)

    Berna Bozkurt Duman

    2014-02-01

    Conclusion: The clinical implication of this discordance rate and it\\'s affect on the choice of appropriate therapy are of critical importance. As such, it would be beneficial for each hospital to determine its own discordance rate.

  11. 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...... University Hospitals (2001-09). The association between delivery interval and adverse outcome parameters were compared for monochorionic (MC) and dichorionic (DC) twins by multiple linear regression. Predictors were studied by logistic regression. Results: There were 554 twin pairs: 57 MC and 485 DC. We...... found no difference in the decrease of pH (p = 0.912) and Apgar (p = 0.609) in relation to increasing time interval. Neonatal unit (NICU) admissions did not differ (p = 0.167). Apgar ≤ 7 (p twin, whereas first (p = 0.001) or second (p twin Apgar...

  12. Dislocation Mechanism of Twinning in Ni-Mn-Ga

    Science.gov (United States)

    Zárubová, N.; Ge, Y.; Gemperlová, J.; Gemperle, A.; Hannula, S.-P.

    2012-03-01

    Tensile tests were performed in situ in a transmission electron microscope to investigate the twinning mechanism in non-modulated Ni-Mn-Ga martensite. The reorientation of the twin variants occurs via twinning dislocations. Their generation and movement were followed; the glide plane and Burgers vector were verified. Individual twinning dislocations were visualized.

  13. On the twinning in ZnPd.

    Science.gov (United States)

    Ivarsson, Dennis C A; Burkhardt, Ulrich; Heggen, Marc; Ormeci, Alim; Armbrüster, Marc

    2017-02-22

    The intermetallic compound ZnPd has demonstrated excellent catalytic properties in methanol steam reforming. While it is known that defects and microstructures influence the catalytic properties, little is known about the defects occurring in ZnPd. Due to recent advances in synthetic methods, coarse-grained ZnPd samples are accessible. This enables the detection and investigation of twinning in ZnPd by studying the twinned regions from the macroscopic scale by polarised light and electron backscattering diffraction (EBSD) down to the atomic scale by high-resolution transmission electron microscopy (HR-TEM). Twinning occurs in {101} and is coupled with a change in the c/a ratio in the vicinity of the twin boundary. Quantum chemical calculations result in only very small energy differences between the ideal and the twinned structure, explaining the experimentally observed thermal stability of the latter. The chemical bonding was investigated by the electron localizability indicator (ELI) and compared to the one in the ideal structure. The results confirm twinning along the {101} plane and demonstrate the high stability of the twin boundaries after formation.

  14. Twin and Triplet Drugs in Opioid Research

    Science.gov (United States)

    Fujii, Hideaki

    Twin and triplet drugs are defined as compounds that contain respectively two and three pharmacophore components exerting pharmacological effects in a molecule. The twin drug bearing the same pharmacophores is a "symmetrical twin drug", whereas that possessing different pharmacophores is a "nonsymmetrical twin drug." In general, the symmetrical twin drug is expected to produce more potent and/or selective pharmacological effects, whereas the nonsymmetrical twin drug is anticipated to show both pharmacological activities stemming from the individual pharmacophores (dual action). On the other hand, nonsymmetrical triplet drugs, which have two of the same pharmacophores and one different moiety, are expected to elicit both increased pharmacological action and dual action. The two identical portions could bind the same receptor sites simultaneously while the third portion could bind a different receptor site or enzyme. This review will mainly focus on the twin and triplet drugs with an evaluation of their in vivo pharmacological effects, and will also include a description of their pharmacology and synthesis.

  15. Mechanical twinning in small quartz crystals

    Science.gov (United States)

    Laughner, J. W.; Newnham, R. E.; Cross, L. E.

    1982-02-01

    Quartz is known to be ferrobielastic; that is, quartz crystals have domain states (Dauphiné twins) which differ in their elastic compliance values and which can be switched by an appropriately oriented stress. Polycrystalline quartz has also been reported (Tullis 1970) to show preferential orientation of these domains following application of large uniaxial stresses. These experiments were designed to study twinning of synthetic quartz “grains” (minimum size 0.07×0.07×0.02 cm) in specially-constructed composites and of grains in three natural quartz aggregates — a quartzite, a novaculite, and a jasper. Backreflection X-ray techniques were used to verify twinning in the composite grains, while special electroding and electrical detection allowed the twinning processes to be examined in “real time.” Small synthetic quartz crystals were found to behave identically to the massive samples previously studied. Electrical pulses due to the reversal of piezoelectric coefficient d 11 in twinned quartz were detected from quartzite and from the man-made composites. Novaculite also gave electrical pulses which were probably from twinning (evidenced by the correlation of expected and observed pulse sizes and shapes), while no pulses from the jaspers indicative of twinning were detected. Grain size distribution differences are considered the main structural reason for the different behaviors.

  16. Teaching about twins: college courses and public lectures.

    Science.gov (United States)

    Segal, Nancy L

    2013-12-01

    The present article describes teaching experiences and observations in college courses and public lectures on twins. It is concluded that much more information about twins, at both research and practical levels, requires general dissemination. This discussion is followed by reviews of recent twin research on the topics of obesity control, post-zygotic mutation, in vitro fertilization, and schisis-associated defects. Media reports of twins accused of rape, infant Chinese twins sold separately for profit, a twin CEO, and twins pursuing the same career are presented.

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

    Directory of Open Access Journals (Sweden)

    Sood S

    2015-10-01

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

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

    DEFF Research Database (Denmark)

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

    2009-01-01

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

  19. Unequal but monozygous: a history of twin-twin transfusion syndrome.

    Science.gov (United States)

    Obladen, Michael

    2010-03-01

    Twin-twin transfusion is the major cause of mortality and morbidity in monochorionic twins. Its pathogenesis has been gradually elucidated over the last three centuries. Among obstetricians, there was a long-lasting controversy on the existence of placental anastomoses and whether or not to tie the placental end of the firstborn infant's cord. However, a twin pregnancy practically never could be excluded. Stalpart van der Wiel described a twin-twin vessel connection in 1687. Studies on interfetal anastomoses using injection of placental vessels were published by Smellie in 1752, Osiander in 1781, and Brachet in 1821. Different types of anastomoses, and their associated fetal disorders were classified by Schatz in a series of papers at the end of the 19(th) century. With the advent of ultrasound and laser techniques, prenatal diagnosis and treatment became available in the last decade of the 20(th) century.

  20. Intravenous nutrition during a twin pregnancy.

    Science.gov (United States)

    Karamatsu, J T; Boyd, A T; Cooke, J; Vinall, P S; McMahon, M J

    1987-01-01

    A case is reported of a woman in the third trimester of a twin pregnancy who required intravenous nutrition because of inadequate absorption of nutrients due to a jejunoileal bypass. Weight gain was poor, and there was evidence of intrauterine growth retardation before commencement of intravenous feeding. She received overnight intravenous nutrition for 6 weeks and gained weight with ultrasound evidence of fetal growth. During the 33rd week of gestation, she was delivered of healthy twin males who were at appropriate birth weights and development for their age of gestation. The considerations in intravenous nutrition for a twin pregnancy after jejunoileal bypass are discussed.

  1. New growth mode through decorated twin boundaries.

    Science.gov (United States)

    Bleikamp, Sebastian; Thoma, Arne; Polop, Celia; Pirug, Gerhard; Linke, Udo; Michely, Thomas

    2006-03-24

    Scanning tunneling microscopy and low energy electron diffraction were used to investigate the growth of partly twinned Ir thin films on Ir(111). A transition from the expected layer-by-layer to a defect dominated growth mode with a fixed lateral length scale and increasing roughness is observed. During growth, the majority of the film is stably transformed to twinned stacking. This transition is initiated by the energetic avoidance of the formation of intrinsic stacking faults compared to two independent twin faults. The atomistic details of the defect kinetics are outlined.

  2. Undiagnosed xiphopagus twins: a perinatal malady

    Directory of Open Access Journals (Sweden)

    Gowri Dorairajan

    2012-02-01

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

  3. Nanoscale growth twins in sputtered metal films

    Energy Technology Data Exchange (ETDEWEB)

    Misra, Amit [Los Alamos National Laboratory; Anderoglu, Osman [Los Alamos National Laboratory; Hoagland, Richard G [Los Alamos National Laboratory; Zhang, X [TEXAS A& M

    2008-01-01

    We review recent studies on the mechanical properties of sputtered Cu and 330 stainless steel films with {l_brace}1 1 1{r_brace} nanoscale growth twins preferentially oriented perpendicular to growth direction. The mechanisms of formation of growth twins during sputtering and the deformation mechanisms that enable usually high strengths in nanotwinned structures are highlighted. Growth twins in sputtered films possess good thermal stability at elevated temperature, providing an approach to extend the application of high strength nanostructured metals to higher temperatures.

  4. 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.

    2015-01-01

    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 clini

  5. Myocardial hypertrophy in the recipient with twin-to-twin transfusion syndrome

    DEFF Research Database (Denmark)

    Jeppesen, D.L.; Jorgensen, F.S.; Pryds, O.A.

    2008-01-01

    In a set of monochorionic-diamniotic twins with twin-to-twin transfusion syndrome, systemic hypertension and biventricular myocardial hypertrophy were found in the recipient. The infant developed mild respiratory distress. A partial exchange transfusion was performed because of polycytaemia. Blood...... pressure measurements revealed persistent systemic hypertension. Biventricular hypertrophy was demonstrated by echocardiography. Blood pressure normalised after treatment with Nifedipine and the cardiac hypertrophy subsided over the following weeks. A potential contributing mechanism is intrauterine...

  6. Anxiety Disorders and Latinos: The Role of Family Cohesion and Family Discord

    Science.gov (United States)

    Priest, Jacob B.; Denton, Wayne

    2012-01-01

    Family cohesion has shown to be associated with lower psychological distress and other risk behaviors for Latinos, but little is known about the relationship of family cohesion, family discord, and anxiety disorders. Using data from the National Latino and Asian American Study (n = 2,554), this study examines the relationship between family…

  7. Scales of Time Where the Quantum Discord Allows an Efficient Execution of the DQC1 Algorithm

    Directory of Open Access Journals (Sweden)

    M. Ávila

    2014-01-01

    Full Text Available The power of one qubit deterministic quantum processor (DQC1 (Knill and Laflamme (1998 generates a nonclassical correlation known as quantum discord. The DQC1 algorithm executes in an efficient way with a characteristic time given by τ=Tr[Un]/2n, where Un is an n qubit unitary gate. For pure states, quantum discord means entanglement while for mixed states such a quantity is more than entanglement. Quantum discord can be thought of as the mutual information between two systems. Within the quantum discord approach the role of time in an efficient evaluation of τ is discussed. It is found that the smaller the value of t/T is, where t is the time of execution of the DQC1 algorithm and T is the scale of time where the nonclassical correlations prevail, the more efficient the calculation of τ is. A Mösbauer nucleus might be a good processor of the DQC1 algorithm while a nuclear spin chain would not be efficient for the calculation of τ.

  8. A membrane cofactor protein transgenic mouse model for the study of discordant xenograft rejection.

    NARCIS (Netherlands)

    N. Yannoutsos (Nikos); J.N.M. IJzermans (Jan); C. Harkes; F. Bonthuis (Fred); C-Y. Zhou; D. White; R.L.M. Marquet; F.G. Grosveld (Frank)

    1996-01-01

    textabstractBACKGROUND: In recent years, interest has been revived in the possibility of transplanting organs into humans from a phylogenetically disparate species such as the pig (xenotransplantation). Such discordant xenografts, however, are subject to hyperacute rejection (HAR) and activation of

  9. Classical correlation and quantum discord mediated by cavity in two coupled qubits

    NARCIS (Netherlands)

    Wang, Cheng-Zhi; Li, Chun-Xian; Nie, Liu-Ying; Li, Jiang-Fan

    2011-01-01

    We study the dynamics of classical correlation and quantum discord of two coupled two-level atoms interacting with a cavity initially in vacuum, coherent and thermal equilibrium states, respectively. The interplay between the atom-atom coupling and mean number of photons is considered. We find that,

  10. Differences in sexual behavior among HIV discordant and concordant gay men in primary relationships.

    Science.gov (United States)

    Hoff, C C; Stall, R; Paul, J; Acree, M; Daigle, D; Phillips, K; Kegeles, S; Jinich, S; Ekstrand, M; Coates, T J

    1997-01-01

    We investigated differences in unprotected anal intercourse among gay men in HIV concordant and discordant primary relationships. Individuals were recruited in 1992 from household- and bar-based samples of gay/bisexual men in Portland, Oregon, and Tucson, Arizona. Respondents were men who reported that they were in primary relationships of > or = 1 month and who reported their own and their partner's HIV status (n = 785). Comparisons were made between three groups: (a) HIV + respondents/HIV + partners; (b) HIV- respondents/HIV- partners; and (c) respondents whose partner's HIV status was different from their own (discordant), on sexual behavior, psychosocial, and demographic variables. Men in HIV concordant relationships reported significantly higher rates of unprotected anal intercourse (54% for +2 and 48% for --) than discordant couples (17%). HIV- men in concordant relationships were more likely to be monogamous (58%) and younger (22% < or = 25 years) than the other two groups. There were no significant differences among the groups regarding the kind of sexual behaviors they engaged in with nonprimary partners. The substantially lower rate of unprotected anal intercourse among men in discordant relationships compared to men in concordant relationships suggests that individuals and couples make judgments about sex and behavior based on knowledge of one's own and one's partner's HIV status.

  11. Exploring Discordance between Self-Efficacy and Writing Performance among Low-Literate Adult Students

    Science.gov (United States)

    Anastasiou, Dimitris; Michail, Domna

    2013-01-01

    The paper explores accordance or discordance between efficacy beliefs of adult students and their writing performance, using a mixed methods design. The participants are 33 students with learning disabilities (LD) and 35 low-achieving (LA) students, who were attending two Second-Chance Schools (SCSs), a specific type of adult education.…

  12. Alexithymia predicts arousal-based processing deficits and discordance between emotion response systems during emotional imagery.

    Science.gov (United States)

    Peasley-Miklus, Catherine E; Panayiotou, Georgia; Vrana, Scott R

    2016-03-01

    Alexithymia is believed to involve deficits in emotion processing and imagery ability. Previous findings suggest that it is especially related to deficits in processing the arousal dimension of emotion, and that discordance may exist between self-report and physiological responses to emotional stimuli in alexithymia. The current study used a well-established emotional imagery paradigm to examine emotion processing deficits and discordance in participants (N = 86) selected based on their extreme scores on the Toronto Alexithymia Scale-20. Physiological (skin conductance, heart rate, and corrugator and zygomaticus electromyographic responses) and self-report (valence, arousal ratings) responses were monitored during imagery of anger, fear, joy, and neutral scenes and emotionally neutral high arousal (action) scenes. Results from regression analyses indicated that alexithymia was largely unrelated to responses on valence-based measures (facial electromyography, valence ratings), but that it was related to arousal-based measures. Specifically, alexithymia was related to higher heart rate during neutral and lower heart rate during fear imagery. Alexithymia did not predict differential responses to action versus neutral imagery, suggesting specificity of deficits to emotional contexts. Evidence for discordance between physiological responses and self-report in alexithymia was obtained from within-person analyses using multilevel modeling. Results are consistent with the idea that alexithymic deficits are specific to processing emotional arousal, and suggest difficulties with parasympathetic control and emotion regulation. Alexithymia is also associated with discordance between self-reported emotional experience and physiological response to emotion, consistent with prior evidence.

  13. Calculation of quantum discord and entanglement measures using the random mutations optimization algorithm

    OpenAIRE

    Chernyavskiy, A. Yu.

    2013-01-01

    The simple and universal global optimization method based on simplified multipopulation genetic algorithm is presented. The method is applied to quantum information problems. It is compared to the genetic algorithm on standard test functions, and also tested on the calculation of quantum discord and minimal entanglement entropy, which is an entanglement measure for pure multipartite states.

  14. Twin boundary energy and characterization of charge redistribution near the twin boundaries of cupperate superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadi, Mahnaz [Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Khoshnevisan, Bahram, E-mail: m.mohammadi_2@grad.kashanu.ac.ir [Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Javad Hashemifar, S. [Department of Physics, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of)

    2014-12-15

    Highlights: • Ab initio simulation for twin boundary energy in YBCO system for the 1st time. • Study of the twin boundary energy variation versus the inserted strain. • Proportionality of twin lamella width by the inserted strain. • Local charge transfer and charge redistribution on the twin planes. • Total DOSs for the twined system at Fermi level is higher than the untwined one. • This explain the effect of twin boundaries in agreement with experimental data. - Abstract: Ab-initio calculations under general gradient approximation have been employed for the first time to find out twin boundary energy, γ, in twined YBCO systems. Despite a vast discrepancy in reported experimental values, our results show that the γ value falls in the range of 40–85 mJ/m{sup 2}. On the other hand, functional form of γ versus inserted strains shows that the mean value for the twin width lamella would tend to approach zero as the strain goes to zero. We have also investigated the local charge transfer and the modification of the electronic states of the basal and twin planes in YBCO, because the charge redistribution at interfaces can modify transport across the grains considerably and determine the applicability of high-T{sub c} superconductors in the electronic applications. The total density of electronic states at the Fermi level for the twined system is enhanced in comparison with the untwined one. Our results explain the influence of twin boundaries in superconductive properties of YBCO, in experimental situations.

  15. Removing the twin image in digital holography by segmented filtering of in-focus twin image

    OpenAIRE

    2008-01-01

    We propose and investigate a new digital method for the reduction of twin-image noise from digital Fresnel holograms. For the case of in-line Fresnel holography the unwanted twin is present as a highly corruptive noise when the object image is numerically reconstructed. We propose to firstly reconstruct the unwanted twin-image when it is in-focus and in this plane we calculate a segmentation mask that borders this in focus image. The twin-image is then segmented and removed by sim...

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

    Directory of Open Access Journals (Sweden)

    Catharina E. M. van Beijsterveldt

    2011-01-01

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

  17. Gene tree discordance of wild and cultivated Asian rice deciphered by genome-wide sequence comparison.

    Science.gov (United States)

    Yang, Ching-chia; Sakai, Hiroaki; Numa, Hisataka; Itoh, Takeshi

    2011-05-15

    Although a large number of genes are expected to correctly solve a phylogenetic relationship, inconsistent gene tree topologies have been observed. This conflicting evidence in gene tree topologies, known as gene tree discordance, becomes increasingly important as advanced sequencing technologies produce an enormous amount of sequence information for phylogenomic studies among closely related species. Here, we aim to characterize the gene tree discordance of the Asian cultivated rice Oryza sativa and its progenitor, O. rufipogon, which will be an ideal case study of gene tree discordance. Using genome and cDNA sequences of O. sativa and O. rufipogon, we have conducted the first in-depth analyses of gene tree discordance in Asian rice. Our comparison of full-length cDNA sequences of O. rufipogon with the genome sequences of the japonica and indica cultivars of O. sativa revealed that 60% of the gene trees showed a topology consistent with the expected one, whereas the remaining genes supported significantly different topologies. Moreover, the proportions of the topologies deviated significantly from expectation, suggesting at least one hybridization event between the two subgroups of O. sativa, japonica and indica. In fact, a genome-wide alignment between japonica and indica indicated that significant portions of the indica genome are derived from japonica. In addition, literature concerning the pedigree of the indica cultivar strongly supported the hybridization hypothesis. Our molecular evolutionary analyses deciphered complicated evolutionary processes in closely related species. They also demonstrated the importance of gene tree discordance in the era of high-speed DNA sequencing.

  18. Nanogeochronology of discordant zircon measured by atom probe microscopy of Pb-enriched dislocation loops.

    Science.gov (United States)

    Peterman, Emily M; Reddy, Steven M; Saxey, David W; Snoeyenbos, David R; Rickard, William D A; Fougerouse, Denis; Kylander-Clark, Andrew R C

    2016-09-01

    Isotopic discordance is a common feature in zircon that can lead to an erroneous age determination, and it is attributed to the mobilization and escape of radiogenic Pb during its post-crystallization geological evolution. The degree of isotopic discordance measured at analytical scales of ~10 μm often differs among adjacent analysis locations, indicating heterogeneous distributions of Pb at shorter length scales. We use atom probe microscopy to establish the nature of these sites and the mechanisms by which they form. We show that the nanoscale distribution of Pb in a ~2.1 billion year old discordant zircon that was metamorphosed c. 150 million years ago is defined by two distinct Pb reservoirs. Despite overall Pb loss during peak metamorphic conditions, the atom probe data indicate that a component of radiogenic Pb was trapped in 10-nm dislocation loops that formed during the annealing of radiation damage associated with the metamorphic event. A second Pb component, found outside the dislocation loops, represents homogeneous accumulation of radiogenic Pb in the zircon matrix after metamorphism. The (207)Pb/(206)Pb ratios measured from eight dislocation loops are equivalent within uncertainty and yield an age consistent with the original crystallization age of the zircon, as determined by laser ablation spot analysis. Our results provide a specific mechanism for the trapping and retention of radiogenic Pb during metamorphism and confirm that isotopic discordance in this zircon is characterized by discrete nanoscale reservoirs of Pb that record different isotopic compositions and yield age data consistent with distinct geological events. These data may provide a framework for interpreting discordance in zircon as the heterogeneous distribution of discrete radiogenic Pb populations, each yielding geologically meaningful ages.

  19. Feasibility of unilateral parathyroidectomy in patients with primary hyperparathyroidism and negative or discordant localization studies.

    Science.gov (United States)

    Calò, Pietro Giorgio; Medas, Fabio; Loi, Giulia; Erdas, Enrico; Pisano, Giuseppe; Nicolosi, Angelo

    2016-06-01

    The purpose of this study was to examine the feasibility of unilateral parathyroidectomy in patients with primary hyperparathyroidism and negative or discordant localization studies. We included in our study 72 patients with preoperative diagnosis of primary hyperparathyroidism who had negative or discordant preoperative studies. In 66 patients, studies were discordant while in six were both negative. In 40 (55.6 %) patients initial approach was a bilateral exploration. In 32 cases (44.4 %) initial surgery was a unilateral exploration: in 26 conservative approach was successful, in six mini-invasive surgery failed and a bilateral exploration was necessary due to IOPTH negative test (five cases) or to the impossibility to find a pathological gland during exploration (one case). Intra-operative PTH test showed a sensitivity of 93.2 %, a specificity of 92.3 %, and an accuracy of 93.1 %. Multiple gland disease was found in 8 (11.1 %) patients (two double adenoma and six multiple gland hyperplasia). Mean operative time was lower in unilateral exploration group (87.9 ± 43.8 min). Comparing unilateral surgery in negative or discordant studies with 77 consecutive patients who underwent focused surgery with positive and concordant studies, conversion to bilateral exploration rate was statistically significantly higher in the first group (15.6 %). We believe that unilateral parathyroidectomy can be safely performed also in patients with discordant localization studies with a high cure rate; in these cases, however, the use of intra-operative PTH is absolutely necessary. We suggest the need for referral of these patients to high-volume medical centers for thyroid and parathyroid surgery.

  20. Temporal ghost imaging with twin photons

    Science.gov (United States)

    Denis, Séverine; Moreau, Paul-Antoine; Devaux, Fabrice; Lantz, Eric

    2017-03-01

    We use twin photons generated by spontaneous parametric down conversion to perform temporal ghost imaging of a single time signal. The retrieval of a binary signal containing eight bits is performed with an error rate below 1%.

  1. Prevention of preterm delivery in twin pregnancy.

    Science.gov (United States)

    Rode, Line; Tabor, Ann

    2014-02-01

    The incidence of twin gestation has increased markedly over the past decades, mostly because of increased use of assisted reproductive technologies. Twin pregnancies are at increased risk of preterm delivery (i.e. birth before 37 weeks of gestation). Multiple gestations therefore account for 2-3% of all pregnancies but constitute at least 10% of cases of preterm delivery. Complications from preterm birth are not limited to the neonatal period, such as in retinopathy of prematurity, intraventricular haemorrhage, necrotising enterocolitis, respiratory disorder and sepsis; they can also constitute sequelae such as abnormal neurophysiological development in early childhood and underachievement in school. Several treatment modalities have been proposed in singleton high-risk pregnancies. The mechanism of initiating labour may, however, be different in singleton and twin gestations. Therefore, it is mandatory to evaluate the proposed treatments in randomised trials of multiple gestations. In this chapter, we describe the results of trials to prevent preterm delivery in twin pregnancies.

  2. Twin Cities Metro Hybrid Landcover 2000 (Raster)

    Data.gov (United States)

    Minnesota Department of Natural Resources — The Hybrid Landcover is an attempt to clean up the University of Minnesota Remote Sensing Lab's 2000 LandSat Land Cover for the Twin Cities 7-county metropolitan...

  3. Spectroscopic study of solar twins and analogues

    CERN Document Server

    Datson, Juliet; Portinari, Laura

    2014-01-01

    Context. Many large stellar surveys have been and are still being carried out, providing huge amounts of data, for which stellar physical parameters will be derived. Solar twins and analogues provide a means to test the calibration of these stellar catalogues because the Sun is the best-studied star and provides precise fundamental parameters. Solar twins should be centred on the solar values. Aims. This spectroscopic study of solar analogues selected from the Geneva-Copenhagen Survey (GCS) at a resolution of 48,000 provides effective temperatures and metallicities for these stars. We test whether our spectroscopic parameters, as well as the previous photometric calibrations, are properly centred on the Sun. In addition, we search for more solar twins in our sample. Methods. The methods used in this work are based on literature methods for solar twin searches and on methods we developed in previous work to distinguish the metallicity-temperature degeneracies in the differential comparison of spectra of solar ...

  4. Thoracopagus conjoined twin: an unusual presentation

    Directory of Open Access Journals (Sweden)

    Rajesh Kumari

    2014-02-01

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

  5. The Radiative Z2 Breaking Twin Higgs

    CERN Document Server

    Yu, Jiang-Hao

    2016-01-01

    In twin Higgs model, the Higgs boson mass is protected by a $Z_2$ symmetry. The $Z_2$ symmetry needs to be broken either explicitly or spontaneously to obtain misalignment between electroweak and new physics vacua. We propose a novel $Z_2$ breaking mechanism, in which the $Z_2$ is spontaneously broken by radiative corrections to the Higgs potential. Two twin Higgses with different vacua are needed, and vacuum misalignment is realized by opposite but comparable contributions from gauge and Yukawa interactions to the potential. Due to fully radiative symmetry breaking, the Higgs sector is completely determined by twin Higgs vacuum, Yukawa and gauge couplings. There are eight pseudo-Goldstone bosons: the Higgs boson, inert doublet Higgs, and three twin scalars. We show the 125 GeV Higgs mass and constraints from Higgs coupling measurements could be satisfied.

  6. Say No to Fake Twin Brothers

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    China vows to fight fake products that exploit a home appliance stimulus project in rural areas Haier Co. Ltd., China’s top home appliance manufacturer, is well known for its logo depicting a pair of twin

  7. Twin Screw Mixer/Fine Grind Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The 40-mm Twin-Screw Mixer/Extruder (TSE) pilot plant is a continuous, remotely operated, flexible facility that can significantly enhance safety and environmental...

  8. Infantile Perineal Protrusion in Two Monochorionic Twins

    Directory of Open Access Journals (Sweden)

    Paola Cavicchioli

    2014-11-01

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

  9. Cooperative Research Twin Trawl Sweep Comparison Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The "Twin-Trawl Sweep Efficiency Study" was intended to compare the sweep efficiency and selectivity of the NEFSC standardized bottom trawl to that of a standardized...

  10. Twin screw subsurface and surface multiphase pumps

    Energy Technology Data Exchange (ETDEWEB)

    Dass, P. [CAN-K GROUP OF COMPANIES, Edmonton, Alberta (Canada)

    2011-07-01

    A new subsurface twin screw multiphase pump has been developed to replace ESP and other artificial lift technologies. This technology has been under development for a few years, has been field tested and is now going for commercial applications. The subsurface twin screw technology consists of a pair of screws that do not touch and can be run with a top drive or submersible motor; and it carries a lot of benefits. This technology is easy to install and its low slippage makes it highly efficient with heavy oil. In addition twin screw multiphase pumps are capable of handling high viscosity fluids and thus their utilization can save water when used in thermal applications. It also induces savings of chemicals because asphaltenes do not break down easily as well as a reduction in SOR. The subsurface twin screw multiphase pump presented herein is an advanced technology which could be used in thermal applications.

  11. Stolen twin: fascination and curiosity/twin research reports: evolution of sleep length; dental treatment of craniopagus twins; cryopreserved double embryo transfer; gender options in multiple pregnancy/current events: appendectomy in one twin; autistic twin marathon runners; 3D facial recognition; twin biathletes.

    Science.gov (United States)

    Segal, Nancy L

    2014-02-01

    The story of her allegedly stolen twin brother in Armenia is recounted by a 'singleton twin' living in the United States. The behavioral consequences and societal implications of this loss are considered. This case is followed by twin research reports on the evolution of sleep length, dental treatment of craniopagus conjoined twins, cryopreserved double embryo transfer (DET), and gender options in multiple pregnancy. Current events include the diagnosis of appendectomy in one identical twin, the accomplishments of autistic twin marathon runners, the power of three-dimensional (3D) facial recognition, and the goals of twin biathletes heading to the 2014 Sochi Olympics in Russia.

  12. Strong crystal size effect on deformation twinning

    DEFF Research Database (Denmark)

    Yu, Qian; Shan, Zhi-Wei; Li, Ju

    2010-01-01

    find that the stress required for deformation twinning increases drastically with decreasing sample size of a titanium alloy single crystal7, 8, until the sample size is reduced to one micrometre, below which the deformation twinning is entirely replaced by less correlated, ordinary dislocation....... The sample size in transition is relatively large and easily accessible in experiments, making our understanding of size dependence11, 12, 13, 14, 15, 16, 17 relevant for applications....

  13. Deformation Twinning During Nanoindentation of Nanocrystalline Ta

    OpenAIRE

    Wang, Y. M.; Hodge, A. M.; Biener, J.; Hamza, A.V.; Barnes, D E; Liu, Kai; Nieh, T. G.

    2005-01-01

    The deformation mechanism of body-centered cubic (bcc) nanocrystalline tantalum with grain sizes of 10–30 nm is investigated by nanoindentation, scanning electron microscopy and high-resolution transmission electron microscopy. In a deviation from molecular dynamics simulations and existing experimental observations on other bcc nanocrystalline metals, the plastic deformation of nanocrystalline Ta during nanoindentation is controlled by deformation twinning. The observation of multiple twin i...

  14. The morphology of the sella turcica in monozygotic twins.

    Science.gov (United States)

    Brock-Jacobsen, Mette T; Pallisgaard, Carsten; Kjaer, Inger

    2009-12-01

    The purpose was to compare the sella turcica morphology of individuals within pairs of monozygotic twins with normal karyotype and to analyze the similarity between the observed morphology and the morphology of non-twins at the same age with normal karyotype. Profile radiographs from 84 individuals of 42 twin pairs (18 male and 24 female pairs, aged 18-23 years) comprised the material. Sella turcica measurements from non-twins aged 6-21 years were used as normal reference. Length, depth and diameter of the sella turcica were measured and controlled by re-measurements. Pearson's correlation coefficient was used for comparison of individuals within twin pairs. For comparison of twins and non-twins, normal standard values for length, depth and diameter were subtracted from the twin values. For the mean values of these differences, confidence limits p values and t values were calculated. The study showed that the size of the sella turcica may be partly similar and partly dissimilar within the pair of monozygotic twins. Statistical evaluation of the data showed correlations between length, depth and diameter of the sella turcica between the two twin individuals in the same twin pair. Differences in sizes are observed between individuals in the twin material and individuals in the non-twin material. As a conclusion, the twin males were more similar within the twin pair, but deviated more from the non-twin material than the females. Female twins had more discrepancy within the twin pair, but deviated less from the non-twin material than the males.

  15. Twin pregnancy in the congenital malformed uterus.

    Science.gov (United States)

    Heinonen, Pentti K

    2016-07-01

    The frequency and outcome of twin pregnancies in women with uterine malformation were studied. The cohort comprised 13 (4.9%) women with twin pregnancy found among 263 women. They had 483 deliveries, 13 of them twins (2.7%; 95% CI 1.6-4.6%). Among 38 patients with unicornuate uterus 5 (6.8%) out of 74 deliveries were twins, 39 women with didelphic uterus 2 (3.2%) out of 62 deliveries and 147 women with septate or subseptate uterus 6 (2.3%) out of 264 deliveries were twins. The mean duration of gestation was 249 days (range 190-268 days), 5 (38%) out of 13 deliveries were premature, 25 out of 26 newborns were alive. Mean durations of gestation and mean weights of newborns did not differ when 7 cases with unicornuate or didelphic uterus were compared to 6 cases with complete or partial uterine septum. A congenital malformed uterus can bear twin pregnancy without severe complications apart from prematurity.

  16. Exotic Quarks in Twin Higgs Models

    CERN Document Server

    Cheng, Hsin-Chia; Salvioni, Ennio; Tsai, Yuhsin

    2015-01-01

    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 ...

  17. The Finnish Twin Cohort Study: an update.

    Science.gov (United States)

    Kaprio, Jaakko

    2013-02-01

    In 2002 and 2006, review papers have described the Finnish Twin Cohort and studies conducted on these population-based, longitudinal data sets with extensive follow-up data. Three cohorts have been established: the older twin cohort in the 1970s, and the Finntwin12 and Finntwin16 studies initiated in the 1990s. The present review provides on update on the latest data collections conducted since the previous review. These cover the fourth waves of data collection in the older cohort (twins born before 1958) and Finntwin12 (twins born 1983-1987). The fifth wave of data collection in Finntwin16 (twins born 1975-1979) also included assessments of their spouses/partners. An analysis of mortality in the older cohort from 1975 to 2009 indicates that the mortality of adult twins (as individuals) does not differ from the population at large. Based on the cohorts, many sub-studies with more detailed phenotyping and collection of omics data have been conducted or are in progress. We also contribute to numerous national and international collaborations.

  18. Acoustic Emission of Deformation Twinning in Magnesium

    Directory of Open Access Journals (Sweden)

    Chengyang Mo

    2016-08-01

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

  19. Urticaria in monozygotic and dizygotic twins

    DEFF Research Database (Denmark)

    Thomsen, Simon Francis; van der Sluis, Sophie; Kyvik, Kirsten Ohm

    2012-01-01

    Aim. To identify risk factors for urticaria, to determine the relative proportion of the susceptibility to urticaria that is due to genetic factors in an adult clinical twin sample, and to further determine whether the genetic susceptibility to urticaria overlaps with the genetic susceptibility...... to atopic diseases. Methods. A total of 256 complete twin pairs and 63 single twins, who were selected from sibships with self-reported asthma via a questionnaire survey of 21,162 adult twins from the Danish Twin Registry, were clinically interviewed about a history of urticaria and examined for atopic.......36-2.72), P = 0.000; and atopic dermatitis, HR = 1.44 (1.02-2.06), P = 0.041 were significant risk factors for urticaria. After adjustment for sex and age at onset of urticaria in the index twin, the risk of urticaria was increased in MZ cotwins relative to DZ cotwins, HR = 1.42 (0.63-3.18), P = 0...

  20. Laying the ghost of twin paradox

    Directory of Open Access Journals (Sweden)

    Popović Marko

    2009-01-01

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

  1. Severe preeclampsia cured by heparin in a patient with twin-twin transfusion syndrome

    Institute of Scientific and Technical Information of China (English)

    CHU Hong-nü; ZHOU Cai-yun

    2007-01-01

    @@ Heparin therapy for preeclampsia has been reported frequently.1-3 Most of the authors used heparin to prevent thrombosis and achieved good results. But its mechanism is not clear.4 Here we describe a case of severe early-onset preeclampsia complicated with hypercoagulable state, fetal growth restriction, and twin-twin transfusion syndrome, that responded well to heparin.

  2. 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.

  3. Spondyloepiphyseal Dysplasia Tarda in Twins

    Directory of Open Access Journals (Sweden)

    Ferhat Çekmez

    2011-08-01

    Full Text Available Introduction: Spondyloepiphyseal dysplasia (SED is a genetically heterogeneous disorder often associated with the early onset of osteoarthrosis. The X-linked recessive form (SEDL affects boys and is characterized by reduced height, arm span exceeding total height, and barrel chest deformity. The radiographic phenotype comprises a hump-shaped deformity of vertebral bodies and mild epiphyseal dysplasia of the femoral head associated with early signs of hip arthrosis.The disorder is caused by mutations in the SEDL (or sedlin gene on Xp22.12-p22.31. SED should be kept in mind as a differential diagnosis in men with early “primary” bilateral osteoarthrosis.Case Report: Here, 11 years old twins diagnosed as SED due to walking disability, limitation of joint motion, pain at the hips and disability in standing for a long time were presented. Discussion: This rare skelatal dysplasia must be kept in mind in patients with painful spine and hip joints, and walking disability. (Jo­ur­nal of Cur­rent Pe­di­at­rics 2011; 9: 97-9

  4. Niobium and tantalum: indispensable twins

    Science.gov (United States)

    Schulz, Klaus; Papp, John

    2014-01-01

    Niobium and tantalum are transition metals almost always paired together in nature. These “twins” are difficult to separate because of their shared physical and chemical properties. In 1801, English chemist Charles Hatchett uncovered an unknown element in a mineral sample of columbite; John Winthrop found the sample in a Massachusetts mine and sent it to the British Museum in London in 1734. The name columbium, which Hatchet named the new element, came from the poetic name for North America—Columbia—and was used interchangeably for niobium until 1949, when the name niobium became official. Swedish scientist Anders Ekberg discovered tantalum in 1802, but it was confused with niobium, because of their twinned properties, until 1864, when it was recognized as a separate element. Niobium is a lustrous, gray, ductile metal with a high melting point, relatively low density, and superconductor properties. Tantalum is a dark blue-gray, dense, ductile, very hard, and easily fabricated metal. It is highly conductive to heat and electricity and renowned for its resistance to acidic corrosion. These special properties determine their primary uses and make niobium and tantalum indispensable.

  5. Treatment of twin-twin transfusion syndrome by fetoscopic laser photocoagulation

    Institute of Scientific and Technical Information of China (English)

    劉子建; 梁德楊; 馮德源; 梁子昂

    2004-01-01

    @@ Twin-twin transfusion syndrome (TTTS) is a serious obstetric complication, occurring in about 15% of monochorionic (MC) twin pregnancies. If untreated, the prognosis is poor, with an overall perinatal mortality of 80%.1 It is now clear that TTTS is the result of an unbalanced unidirectional blood flow through placental arteriovenous anastomoses (also termed deep anastomoses) between the two fetal circulations.2 The donor twin progressively becomes anemic, and develops growth restriction, oliguria, and oligohydramnios/anhydramnios; whereas the recipient becomes plethoric and polyuric, and develops congestive heart failure, cardiomegaly, polyhydramnios and fetal hydrops. Preterm labor is common because of gross polyhydramnios, and further deteriorations will lead to intrauterine death of both twins.

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

    Directory of Open Access Journals (Sweden)

    Sascha Schwarz

    2015-12-01

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

  7. Atopic diseases in twins born after assisted reproduction

    DEFF Research Database (Denmark)

    Jäderberg, Ida; Thomsen, Simon F; Kyvik, Kirsten Ohm

    2012-01-01

    Jäderberg I, Thomsen SF, Kyvik KO, Skytthe A, Backer V. Atopic diseases in twins born after assisted reproduction. Paediatric and Perinatal Epidemiology 2012; 26: 140-145. We examined the risk of atopic diseases in twins born after assisted reproduction. Data on atopic diseases and assisted...... reproduction in 9694 twin pairs, 3-20 years of age, from the Danish Twin Registry were collected via multidisciplinary questionnaires. The risk of atopic diseases in twins born after assisted reproduction was compared with the risk in twins born after spontaneous conception using logistic regression...

  8. Twin studies in auto-immune disease.

    Science.gov (United States)

    Leslie, R D; Hawa, M

    1994-01-01

    Immune-mediated diseases affect up to 5% of the population and are a major cause of morbidity and mortality. These diseases can be organ specific, such as insulin-dependent diabetes (IDDM) and non-organ specific, such as Rheumatoid Arthritis (RA). Identical and non-identical twins have been used to establish whether these diseases are determined by genetic or environmental factors. The results of these studies have been collated in a new section of the Mendel Institute in Rome. Diseases included in these studies included IDDM, RA, Systemic Lupus Erythematosus (SLE), Multiple Sclerosis (MS) and Myasthenia. Striking differences in concordance rates between identical and non-identical twins in all these studies suggest that genetic factors are important in causing these diseases. All the diseases are known to be associated with HLA genes on chromosome 6 which may account for some or all of the genetic susceptibility. However, in the majority of pairs the affected twin has an unaffected co-twin. These observations suggest that non-genetically determined factors, probably environmental factors and not somatic mutations, are critical. The study of unaffected co-twins, who are at high disease-risk, has allowed the identification of changes which precede and predict the clinical disease. The immune-mediated destruction in many of these diseases is probably caused by T-lymphocytes. Twin studies have shown the importance of genetic factors in determining T-cell responses. Identical twins should, therefore, provide the perfect test bed to assess the role of T-cells in immune-mediated diseases.

  9. 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.

  10. Pairwise correlations via quantum discord and its geometric measure in a four-qubit spin chain

    Directory of Open Access Journals (Sweden)

    Abdel-Baset A. Mohamed

    2013-04-01

    Full Text Available The dynamic of pairwise correlations, including quantum entanglement (QE and discord (QD with geometric measure of quantum discord (GMQD, are shown in the four-qubit Heisenberg XX spin chain. The results show that the effect of the entanglement degree of the initial state on the pairwise correlations is stronger for alternate qubits than it is for nearest-neighbor qubits. This parameter results in sudden death for QE, but it cannot do so for QD and GMQD. With different values for this entanglement parameter of the initial state, QD and GMQD differ and are sensitive for any change in this parameter. It is found that GMQD is more robust than both QD and QE to describe correlations with nonzero values, which offers a valuable resource for quantum computation.

  11. Geometric Quantum Discord in the Heisenberg XX Model with Three-Spin Interactions

    Science.gov (United States)

    Xie, Yu-Xia; Liu, Jing; Sun, Yu-Hang

    2016-11-01

    Quantum discord is a resource for quantum information processing tasks, and seeking flexible ways to control it is of practical significance. We investigate the trace distance, Bures distance, and Hellinger distance geometric quantum discords (GQDs) for thermal states of the Heisenberg XX chain with three-spin interactions. The results show that both the XZX + YZY and XZY -YZX types of three-spin interactions can be used to enhance evidently the GQDs for the boundary spins of the chain. The optimal strengths of three-spin interactions for which the maximum enhancement of the GQDs are achieved are strongly dependent on the GQD measures we adopted and the number of spins in the chain.

  12. Classifying directional Gaussian entanglement, Einstein-Podolsky-Rosen steering, and discord.

    Science.gov (United States)

    He, Q Y; Gong, Q H; Reid, M D

    2015-02-13

    Using Venn diagrams, we classify the different types of two-mode Gaussian continuous variable quantum correlation including directional entanglement and Einstein-Podolsky-Rosen (EPR) steering. We establish unified signatures for one- and two-way quantum steering, entanglement, and discord beyond entanglement in terms of an EPR-type variance. By focusing on Gaussian states, we link an optimized condition for entanglement based on an EPR variance to the Simon-Peres condition. This allows us to quantify the asymmetry of the Gaussian entanglement, and to relate the asymmetry to a directional quantum teleportation protocol where Alice and Bob possess asymmetrically noisy channels. Our analysis enables a determination of the type and direction of quantum correlation in a way that is easily measured in experiment. We also find that for symmetric states, when discord exceeds a certain threshold, the states are necessarily steerable.

  13. Geometric Quantum Discord in the Heisenberg XX Model with Three-Spin Interactions

    Science.gov (United States)

    Xie, Yu-Xia; Liu, Jing; Sun, Yu-Hang

    2017-02-01

    Quantum discord is a resource for quantum information processing tasks, and seeking flexible ways to control it is of practical significance. We investigate the trace distance, Bures distance, and Hellinger distance geometric quantum discords (GQDs) for thermal states of the Heisenberg XX chain with three-spin interactions. The results show that both the XZX + YZY and XZY - YZX types of three-spin interactions can be used to enhance evidently the GQDs for the boundary spins of the chain. The optimal strengths of three-spin interactions for which the maximum enhancement of the GQDs are achieved are strongly dependent on the GQD measures we adopted and the number of spins in the chain.

  14. Quantum Discord and Entanglement of Quasi-Werner States Based on Bipartite Entangled Coherent States

    Science.gov (United States)

    Mishra, Manoj K.; Maurya, Ajay K.; Prakash, Hari

    2016-06-01

    Present work is an attempt to compare quantum discord and quantum entanglement of quasi-Werner states formed with the four bipartite entangled coherent states (ECS) used recently for quantum teleportation of a qubit encoded in superposed coherent state. Out of these, the quasi-Werner states based on maximally ECS due to its invariant nature under local operation is independent of measurement basis and mean photon numbers, while for quasi-Werner states based on non-maximally ECS, it depends upon measurement basis as well as on mean photon number. However, for large mean photon numbers since non-maximally ECS becomes almost maximally entangled therefore dependence of quantum discord for non-maximally ECS based quasi-Werner states on the measurement basis disappears.

  15. Unidirectional Pinning and Hysteresis of Spatially Discordant Alternans in Cardiac Tissue

    CERN Document Server

    Skardal, Per Sebastian; Restrepo, Juan G

    2011-01-01

    Spatially discordant alternans is a widely observed pattern of voltage and calcium signals in cardiac tissue that can precipitate lethal cardiac arrhythmia. Using spatially coupled iterative maps of the beat-to-beat dynamics, we explore this pattern's dynamics in the regime of a calcium-dominated period-doubling instability at the single cell level. We find a novel nonlinear bifurcation associated with the formation of a discontinuous jump in the amplitude of calcium alternans at nodal lines separating discordant regions. We show that this jump unidirectionally pins nodal lines by preventing their motion away from the pacing site following a pacing rate decrease, but permitting motion towards this site following a rate increase. This unidirectional pinning leads to strongly history-dependent nodal line motion that is strongly arrhythmogenic.

  16. Characterizing the dynamics of quantum discord under phase damping with POVM measurements

    Institute of Scientific and Technical Information of China (English)

    蒋峰建; 叶剑锋; 闫新虎; 吕海江

    2015-01-01

    In the analysis of quantum discord, the minimization of average entropy traditionally involved over orthogonal projec-tive measurements may be attained at more optimal decompositions by using the positive-operator-valued measure (POVM) measurements. Taking advantage of the quantum steering ellipsoid in combination with three-element POVM optimization, we show that, for a family of two-qubit X states locally interacting with Markovian non-dissipative environments, the decay rates of quantum discord show smooth dynamical evolutions without any sudden change. This is in contrast to two-element orthogonal projective measurements, in which case the sudden change of the decay rates of quantum and classical decoher-ences may be a common phenomenon. Notwithstanding this, we find that a subset of X states (including the Bell diagonal states) involving POVM optimization can still preserve the sudden change character as usual.

  17. Characterization of Gastric Microbiota in Twins.

    Science.gov (United States)

    Dong, Quanjiang; Xin, Yongning; Wang, Lili; Meng, Xinying; Yu, Xinjuan; Lu, Linlin; Xuan, Shiying

    2017-02-01

    Contribution of host genetic backgrounds in the development of gastric microbiota has not been clearly defined. This study was aimed to characterize the biodiversity, structure and composition of gastric microbiota among twins. A total of four pairs of twins and eight unrelated individuals were enrolled in the study. Antral biopsies were obtained during endoscopy. The bacterial 16S rRNA gene was amplified and pyrosequenced. Sequences were analyzed for the composition, structure, and α and β diversities of gastric microbiota. Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, and Fusobacteria were the most predominant phyla of gastric microbiota. Each individual, twins as well as unrelated individuals, harbored a microbiota of distinct composition. There was no evidence of additional similarity in the richness and evenness of gastric microbiota among co-twins as compared to unrelated individuals. Calculations of θYC and PCoA demonstrated that the structure similarity of gastric microbial community between co-twins did not increase compared to unrelated individuals. In contrast, the structure of microbiota was altered enormously by Helicobacter pylori infection. These results suggest that host genetic backgrounds had little effect in shaping the gastric microbiota. This property of gastric microbiota could facilitate the studies discerning the role of microbiota from genetic grounds in the pathogenesis.

  18. Using NS5B Sequencing for Hepatitis C Virus Genotyping Reveals Discordances with Commercial Platforms

    Science.gov (United States)

    Chueca, Natalia; Rivadulla, Isidro; Lovatti, Rubén; Reina, Gabriel; Blanco, Ana; Fernandez-Caballero, Jose Angel; Cardeñoso, Laura; Rodriguez-Granjer, Javier; Fernandez-Alonso, Miriam; Aguilera, Antonio; Alvarez, Marta

    2016-01-01

    We aimed to evaluate the correct assignment of HCV genotypes by three commercial methods—Trugene HCV genotyping kit (Siemens), VERSANT HCV Genotype 2.0 assay (Siemens), and Real-Time HCV genotype II (Abbott)—compared to NS5B sequencing. We studied 327 clinical samples that carried representative HCV genotypes of the most frequent geno/subtypes in Spain. After commercial genotyping, the sequencing of a 367 bp fragment in the NS5B gene was used to assign genotypes. Major discrepancies were defined, e.g. differences in the assigned genotype by one of the three methods and NS5B sequencing, including misclassification of subtypes 1a and 1b. Minor discrepancies were considered when differences at subtype levels, other than 1a and 1b, were observed. The overall discordance with the reference method was 34% for Trugene and 15% for VERSANT HCV2.0. The Abbott assay correctly identified all 1a and 1b subtypes, but did not subtype all the 2, 3, 4 and 5 (34%) genotypes. Major discordances were found in 16% of cases for Trugene HCV, and the majority were 1b- to 1a-related discordances; major discordances were found for VERSANT HCV 2.0 in 6% of cases, which were all but one 1b to 1a cases. These results indicated that the Trugene assay especially, and to a lesser extent, Versant HCV 2.0, can fail to differentiate HCV subtypes 1a and 1b, and lead to critical errors in clinical practice for correctly using directly acting antiviral agents. PMID:27097040

  19. Cardio-Metabolic Features of Type 2 Diabetes Subjects Discordant in the Diagnosis of Metabolic Syndrome

    Directory of Open Access Journals (Sweden)

    Sa Rah Lee

    2012-10-01

    Full Text Available BackgroundThe aim of this study is to investigate the cardio-metabolic parameters and surrogate markers of insulin resistance in a discordant group of type 2 diabetes (T2DM subjects who satisfy the Adults Treatment Panel (ATP III criteria, but not the International Diabetes Federation (IDF criteria, for metabolic syndrome (MetS.MethodsWe assessed the prevalence of MetS in T2DM subjects (n=167 who were selected from subjects registered at the diabetes center of Dong-A University Medical Center. We used the ATP III criteria and the IDF criteria for the diagnosis of MetS and sorted the subjects into 2 MetS groups: one group diagnosed per ATP III criteria (MetSa and one diagnosed per IDF criteria (MetSi. We then compared the clinical characteristics, metabolic parameters (homeostasis model assessment of insulin resistance, aspartate aminotransferase, alanine aminotransferase, and uric acid values and co-morbidities (prevalence of microalbuminuria, fatty liver, and cardiovascular disease between the MetSa, MetSi, and discordant MetS groups.ResultsThe prevalence of MetS in the MetSa group (73.6% was higher than in the MetSi group (62.2%. The MetS prevalence in the discordant group was 11.4%. The discordant group showed no significant differences in clinical characteristics (except waist circumference and body mass index, metabolic parameters, or prevalence of co-morbidities, as compared with subjects with MetS by both criteria.ConclusionIn this study, cardio-metabolic features of the subjects diagnosed with MetS using ATP III criteria, but not IDF criteria, are not significantly different from those of subjects diagnosed with MetS using both criteria.

  20. Geographical Patterns of HIV Sero-Discordancy in High HIV Prevalence Countries in Sub-Saharan Africa

    Directory of Open Access Journals (Sweden)

    Diego F. Cuadros

    2016-08-01

    Full Text Available Introduction: Variation in the proportion of individuals living in a stable HIV sero-discordant partnership (SDP, and the potential drivers of such variability across sub Saharan Africa (SSA, are still not well-understood. This study aimed to examine the spatial clustering of HIV sero-discordancy, and the impact of local variation in HIV prevalence on patterns of sero-discordancy in high HIV prevalence countries in SSA. Methods: We described the spatial patterns of sero-discordancy among stable couples by analyzing Demographic and Health Survey data from Cameroon, Kenya, Lesotho, Tanzania, Malawi, Zambia, and Zimbabwe. We identified spatial clusters of SDPs in each country through a Kulldorff spatial scan statistics analysis. After a geographical cluster was identified, epidemiologic measures of sero-discordancy were calculated and analyzed. Results: Spatial clusters with significantly high numbers of SDPs were identified and characterized in Kenya, Malawi, and Tanzania, and they largely overlapped with the clusters with high HIV prevalence. There was a positive correlation between HIV prevalence and the proportion of SDPs among all stable couples across within and outside clusters. Conversely, there was a negative, but weak and not significant, correlation between HIV prevalence and the proportion of SDPs among all stable couples with at least one HIV-infected individual in the partnership. Discussion: There does not appear to be distinct spatial patterns for HIV sero-discordancy that are independent of HIV prevalence patterns. The variation of the sero-discordancy measures with HIV prevalence across clusters and outside clusters demonstrated similar patterns to those observed at the national level. The spatial variable does not appear to be a fundamental nor independent determinant of the observed patterns of sero-discordancy in high HIV prevalence countries in SSA.

  1. Dynamics of tripartite quantum entanglement and discord under a classical dephasing random telegraph noise

    Science.gov (United States)

    Kenfack, Lionel Tenemeza; Tchoffo, Martin; Fai, Lukong Cornelius

    2017-02-01

    We address the dynamics of quantum correlations, including entanglement and quantum discord of a three-qubit system interacting with a classical pure dephasing random telegraph noise (RTN) in three different physical environmental situations (independent, mixed and common environments). Two initial entangled states of the system are examined, namely the Greenberger-Horne-Zeilinger (GHZ)- and Werner (W)-type states. The classical noise is introduced as a stochastic process affecting the energy splitting of the qubits. With the help of suitable measures of tripartite entanglement (entanglement witnesses and lower bound of concurrence) and quantum discord (global quantum discord and quantum dissension), we show that the evolution of quantum correlations is not only affected by the type of the system-environment interaction but also by the input configuration of the qubits and the memory properties of the environmental noise. Indeed, depending on the memory properties of the environmental noise and the initial state considered, we find that independent, common and mixed environments can play opposite roles in preserving quantum correlations, and that the sudden death and revival phenomena or the survival of quantum correlations may occur. On the other hand, we also show that the W-type state has strong dynamics under this noise than the GHZ-type ones.

  2. Quantum Discord, CHSH Inequality and Hidden Variables -- Critical reassessment of hidden-variables models

    CERN Document Server

    Fujikawa, Kazuo

    2013-01-01

    Hidden-variables models are critically reassessed. It is first examined if the quantum discord is classically described by the hidden-variable model of Bell in the Hilbert space with $d=2$. The criterion of vanishing quantum discord is related to the notion of reduction and, surprisingly, the hidden-variable model in $d=2$, which has been believed to be consistent so far, is in fact inconsistent and excluded by the analysis of conditional measurement and reduction. The description of the full contents of quantum discord by the deterministic hidden-variables models is not possible. We also re-examine CHSH inequality. It is shown that the well-known prediction of CHSH inequality $|B|\\leq 2$ for the CHSH operator $B$ introduced by Cirel'son is not unique. This non-uniqueness arises from the failure of linearity condition in the non-contextual hidden-variables model in $d=4$ used by Bell and CHSH, in agreement with Gleason's theorem which excludes $d=4$ non-contextual hidden-variables models. If one imposes the l...

  3. Are you HIV invincible? A probabilistic study of discordant couples in the context of HIV transmission.

    Directory of Open Access Journals (Sweden)

    Georgiy Bobashev

    Full Text Available A number of factors have been identified that are related to sexual and injecting HIV transmission. We developed a probabilistic mathematical model to put these factors together and interpret risks in the context of individual behavior among injecting drug-using (IDU couples in St. Petersburg, Russia. Some HIV-discordant couples have unprotected sex and sometimes inject drugs together but stay discordant for a long time, while some individuals acquire HIV on the first encounter. We considered existing estimates of HIV transmission risks through injecting and sexual contacts to develop a predictive survival model for an individual who is exposed to HIV through intimate relationships. We computed simulated survival curves for a number of behavioral scenarios and discussed sources of simulated uncertainty. We then applied the model to a longitudinal study of HIV-discordant couples and validated the model's forecast. Although individual prediction of seroconversion time appeared impossible, the ability to rank behavioral patterns in terms of HIV risk and to estimate the probability of survival HIV-free will be important to educators and counselors.

  4. Astronaut Twins Give Clues to Health Hazards of Spaceflight

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_163391.html Astronaut Twins Give Clues to Health Hazards of Spaceflight NASA ... aboard the International Space Station, and his identical twin Mark, a retired astronaut. Mark remained on Earth ...

  5. Heritability of eleven metabolic phenotypes in Danish and Chinese twins

    DEFF Research Database (Denmark)

    Li, Shuxia; Duan, Hongmei; Pang, Zengchang

    2013-01-01

    A twin-based comparative study on the genetic influences in metabolic endophenotypes in two populations of substantial ethnic, environmental, and cultural differences was performed. Design and Methods: Data on 11 metabolic phenotypes including anthropometric measures, blood glucose, and lipids...... levels as well as blood pressure were available from 756 pairs of Danish twins (309 monozygotic and 447 dizygotic twin pairs) with a mean age of 38 years (range: 18-67) and from 325 pairs of Chinese twins (183 monozygotic and 142 dizygotic twin pairs) with a mean age of 40.5 years (range: 18-69). Twin...... similar heritability patterns in the two samples with body weight showing only a slight difference. Higher genetic influences were estimated for fasting blood glucose level in Chinese twins, whereas the Danish twins showed more genetic regulation over most lipids phenotypes. Systolic blood pressure...

  6. Twin studies reveal specific imbalances in the mucosa-associated microbiota of patients with ileal Crohn's disease

    Energy Technology Data Exchange (ETDEWEB)

    Willing, B.; Halfvarson, J.; Dicksved, J.; Rosenquist, M.; Jarnerot, G.; Engstrand, L.; Tysk, C.; Jansson, J. K

    2008-08-15

    Large inter-individual variation in the composition of the intestinal microbiota between unrelated individuals has made it challenging to identify specific aspects of dysbiosis that lead to Crohn's disease. To reduce variations in exposure during establishment of the gut flora and influence of genotype, we studied the mucosaassociated microbiota of monozygotic twin pairs that were discordant (n=6) or concordant (n=4) for Crohn's disease. DNA was extracted from biopsies collected from 5 locations between the ileum and rectum. Bacterial 16S ribosomal RNA genes were amplified and community composition assessed by terminal-restriction fragment length polymorphism, cloning and sequencing and quantitative real-time PCR. The microbial compositions at all biopsy locations for each individual were similar, regardless of disease state, but there were differences between individuals. In particular, individuals with predominantly ileal Crohn's had a dramatically lower abundance (P<0.001) of Faecalibacterium prausnitzii and increased abundance (P<0.03) of Escherichia coli compared to healthy co-twins and those with Crohn's localized in the colon. This dysbiosis was significantly correlated to the disease phenotype rather than genotype. The reduced abundance of F. prausnitzii and increased abundance of E. coli are indicative of an ileal Crohn's disease phenotype, distinct from colonic Crohn's disease and the relative abundances of these specific bacterial populations are promising biomarker candidates for differential diagnosis of Crohn's and eventually customized treatment.

  7. Maternal age at first birth and offspring criminality: using the children of twins design to test causal hypotheses.

    Science.gov (United States)

    Coyne, Claire A; Långström, Niklas; Rickert, Martin E; Lichtenstein, Paul; D'Onofrio, Brian M

    2013-02-01

    Teenage childbirth is a risk factor for poor offspring outcomes, particularly offspring antisocial behavior. It is not clear, however, if maternal age at first birth (MAFB) is causally associated with offspring antisocial behavior or if this association is due to selection factors that influence both the likelihood that a young woman gives birth early and that her offspring engage in antisocial behavior. The current study addresses the limitations of previous research by using longitudinal data from Swedish national registries and children of siblings and children of twins comparisons to identify the extent to which the association between MAFB and offspring criminal convictions is consistent with a causal influence and confounded by genetic or environmental factors that make cousins similar. We found offspring born to mothers who began childbearing earlier were more likely to be convicted of a crime than offspring born to mothers who delayed childbearing. The results from comparisons of differentially exposed cousins, especially born to discordant monozygotic twin sisters, provide support for a causal association between MAFB and offspring criminal convictions. The analyses also found little evidence for genetic confounding due to passive gene-environment correlation. Future studies are needed to replicate these findings and to identify environmental risk factors that mediate this causal association.

  8. A Twin Protection Effect? Explaining Twin Survival Advantages with a Two-Process Mortality Model.

    Science.gov (United States)

    Sharrow, David J; Anderson, James J

    2016-01-01

    Twin studies that focus on the correlation in age-at-death between twin pairs have yielded important insights into the heritability and role of genetic factors in determining lifespan, but less attention is paid to the biological and social role of zygosity itself in determining survival across the entire life course. Using data from the Danish Twin Registry and the Human Mortality Database, we show that monozygotic twins have greater cumulative survival proportions at nearly every age compared to dizygotic twins and the Danish general population. We examine this survival advantage by fitting these data with a two-process mortality model that partitions survivorship patterns into extrinsic and intrinsic mortality processes roughly corresponding to acute, environmental and chronic, biological origins. We find intrinsic processes confer a survival advantage at older ages for males, while at younger ages, all monozygotic twins show a health protection effect against extrinsic death akin to a marriage protection effect. While existing research suggests an increasingly important role for genetic factors at very advanced ages, we conclude that the social closeness of monozygotic twins is a plausible driver of the survival advantage at ages <65.

  9. Aging and communication in the twin paradox

    CERN Document Server

    de Wolf, David A

    2016-01-01

    The twin paradox of the special theory of relativity has given rise to a large body of literature discussing its implications. In its standard form, the traveler changes velocity only at the destination of the trip, so that he appears to perceive an improbably instantaneous and non-continuous change in age of the stationary twin. In this work, a smooth velocity/acceleration profile is used that allows the abrupt velocity-change case as a limit. All gravitational effects are ignored in this treatment. Aside from mutual perception of simultaneous clock times in an accelerating frame, constant communication of clock times between the twins by means of (digital) light signals is shown to be possible, in principle if not in practice.

  10. Aging and communication in the twin paradox

    Science.gov (United States)

    de Wolf, David A.

    2016-11-01

    The twin paradox of the special theory of relativity has given rize to a large body of literature discussing its implications. In its standard form, the traveler changes velocity only at the destination of the trip, so that he appears to perceive an improbably instantaneous and non-continuous change in age of the stationary twin. In this work, a smooth velocity/acceleration profile is used that allows the abrupt velocity-change case as a limit. All gravitational effects are ignored in this treatment. Aside from mutual perception of simultaneous clock times in an accelerating frame, constant communication of clock times between the twins by means of (digital) light signals is shown to be possible, in principle if not in practice.

  11. Time, Topology and the Twin Paradox

    CERN Document Server

    Luminet, J -P

    2009-01-01

    The twin paradox is the best known thought experiment associated with Einstein's theory of relativity. An astronaut who makes a journey into space in a high-speed rocket will return home to find he has aged less than a twin who stayed on Earth. This result appears puzzling, since the situation seems symmetrical, as the homebody twin can be considered to have done the travelling with respect to the traveller. Hence it is called a "paradox". In fact, there is no contradiction and the apparent paradox has a simple resolution in Special Relativity with infinite flat space. In General Relativity (dealing with gravitational fields and curved space-time), or in a compact space such as the hypersphere or a multiply connected finite space, the paradox is more complicated, but its resolution provides new insights about the structure of spacetime and the limitations of the equivalence between inertial reference frames.

  12. Solar twins in the ELODIE archive

    CERN Document Server

    Mahdi, Dhiaa; Blanco-Cuaresma, Sergi; Chemin, Laurent

    2016-01-01

    A large dataset of ~2800 spectra extracted from the ELODIE archive was analysed in order to find solar twins. A list of stellar spectra closely resembling the spectrum of the Sun was selected by applying a purely differential method, directly on the fluxes. As solar reference, 18 spectra of asteroids, Moon and blue sky were used. Atmospheric parameters and differential abundances of 8 chemical elements were determined for the solar twin candidates, after a careful selection of appropriate lines. The Li feature of the targets was investigated and additional information on absolute magnitude and age was gathered from the literature. HIP076114 (HD138573) is our best twin candidate, looking exactly like the Sun in all these properties.

  13. Plasmonic twinned silver nanoparticles with molecular precision

    Science.gov (United States)

    Yang, Huayan; Wang, Yu; Chen, Xi; Zhao, Xiaojing; Gu, Lin; Huang, Huaqi; Yan, Juanzhu; Xu, Chaofa; Li, Gang; Wu, Junchao; Edwards, Alison J.; Dittrich, Birger; Tang, Zichao; Wang, Dongdong; Lehtovaara, Lauri; Häkkinen, Hannu; Zheng, Nanfeng

    2016-09-01

    Determining the structures of nanoparticles at atomic resolution is vital to understand their structure-property correlations. Large metal nanoparticles with core diameter beyond 2 nm have, to date, eluded characterization by single-crystal X-ray analysis. Here we report the chemical syntheses and structures of two giant thiolated Ag nanoparticles containing 136 and 374 Ag atoms (that is, up to 3 nm core diameter). As the largest thiolated metal nanoparticles crystallographically determined so far, these Ag nanoparticles enter the truly metallic regime with the emergence of surface plasmon resonance. As miniatures of fivefold twinned nanostructures, these structures demonstrate a subtle distortion within fivefold twinned nanostructures of face-centred cubic metals. The Ag nanoparticles reported in this work serve as excellent models to understand the detailed structure distortion within twinned metal nanostructures and also how silver nanoparticles can span from the molecular to the metallic regime.

  14. Infant mortality in twin pregnancies following in-utero demise of the co-twin

    Institute of Scientific and Technical Information of China (English)

    Boubakari Ibrahimou; Hamisu M Salihu; Muktar H Aliyu; Gary English; Getachew Dagne

    2015-01-01

    Objective:To assess whether conversion from twin to singleton pregnancy following the demise of a co-twin influences survival.Methods:This retrospective study compared the risk for neonatal, post-neonatal and infant death for converted co-twins versus unconverted co-twins using the US matched multiple file dataset for the period 1995-2000. We also examined the same risks for converted versus same-quantile co-twins, hazard ratios (HR) and 95% confidence intervals (CI) were computed using Cox Proportional Hazards models.Results:The risk for neonatal (HR=0.18, 95%CI: 0.09-0.34 andHR=0.69, 95%CI: 0.50- 0.96) and infant death (HR=0.22, 95%CI: 0.12-0.42 andHR=0.57, 95%CI: 0.42-0.77) were significantly lower for converted twins than for unconverted twins and same-quantile twins, respectively. For black compared to white, the risk for post-neonatal death increased by 89% (HR=1.89, 95%CI= 1.03, 3.48), and 79% (HR=1.79, 95%CI=1.53, 2.09) for convertedvs. unconverted and convertedvs. same-quantile, respectively. For converted black, the risk for neonatal death decreased by 17% (HR=0.83, 95%CI=0.73-0.93) as compared to unconverted.Conclusions: Risks for all mortality types were lower among converted co-twins than their unconverted or same-quantile counterparts. The lower neonatal and higher post-neonatal mortality among black require future research.

  15. A note on twin-singleton differences in asthma

    DEFF Research Database (Denmark)

    Thomsen, Simon Francis; Kyvik, Kirsten Ohm; Backer, Vibeke

    2008-01-01

    Twins constitute a valuable resource for genetic studies of asthma. However, critics argue that twins are 'special' in terms of prenatal environment and upbringing and therefore nonrepresentative. In respect to asthma a small range of studies report differential morbidity in twins compared...... with singletons. We review some of the possible explanations for these findings and conclude that results from twin studies of asthma can be extrapolated to the general population....

  16. Fetal MRI of conjoined twins who switched their relative positions

    Energy Technology Data Exchange (ETDEWEB)

    Huisman, Thierry A.G.M. [University Children' s Hospital, Department of Diagnostic Imaging, Zurich (Switzerland); Johns Hopkins Hospital, Division of Pediatric Radiology, Department of Radiology and Radiological Science, Baltimore, MD (United States); Arulrajah, Sahayini [Johns Hopkins Hospital, Division of Pediatric Radiology, Department of Radiology and Radiological Science, Baltimore, MD (United States); Meuli, Martin [University Children' s Hospital, Department of Surgery, Zurich (Switzerland); Brehmer, Ulrike [University Children' s Hospital, Department of Diagnostic Imaging, Zurich (Switzerland); Beinder, Ernst [University Hospital, Department of Obstetrics, Zurich (Switzerland)

    2010-03-15

    Conjoined twinning is a very rare occurrence with no genetic predisposition. Twisting of conjoined twins around the axis of their connecting tissue bridge, close to the third trimester, has not been previously reported. We describe a unique case of in utero twisting of conjoined omphalopagus twins who survived without any adverse effects. Fetal US and fetal MRI played a vital role in the diagnosis and perinatal management of these twins. (orig.)

  17. Urticaria in Monozygotic and Dizygotic Twins

    Directory of Open Access Journals (Sweden)

    Simon Francis Thomsen

    2012-01-01

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

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

    Science.gov (United States)

    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.

  19. Sexual violence and associated factors among women in HIV discordant and concordant relationships in Uganda.

    Science.gov (United States)

    Shuaib, Faisal M B; Ehiri, John E; Jolly, Pauline; Zhang, Qionghui; Emusu, Donath; Ngu, Julius; Foushee, Herman; Katongole, Drake; Kirby, Russell; Wabwire-Mangen, Fred

    2012-01-01

    HIV serodiscordance is a sexual partnership in which one partner is infected with HIV while the other is not. Managing emotional and sexual intimacy in HIV serodiscordant unions can be difficult due to concerns about HIV transmission and the challenge of initiating and maintaining safe sex. In situations where couples are jointly aware of their HIV status, women in serodiscordant unions may face increased risk of partner violence. We conducted an investigation to assess risk factors for HIV serodiscordance and determine if HIV serodiscordance is associated with incident sexual violence among a cohort of women attending HIV post-test club services at three AIDS Information Centers (AICs) in Uganda. Using a prospective study of 250 women, we elicited information about sexual violence using structured face-to-face interviews. Sexual violence and risk factors were assessed and compared among HIV positive women in HIV discordant unions, HIV negative women in discordant unions, and HIV negative women in negative concordant unions. Multivariable logistic regression was used to assess the association between participants' serostatus and sexual violence. HIV negative women in serodiscordant relationships (36.1±11.1 years, range: 19-65 years) were significantly older than either HIV positive women in serodiscordant relationships (32.2±9.0 years, range: 18-56 years), or HIV negative women in concordant relationships (32.3±11.0 years, range: 18-62), (p=0.033). Early age at sexual debut was associated with a 2.4-fold increased risk of experiencing sexual violence (OR 2.4, 95% CI 1.27-4.65). Based on unadjusted analysis, HIV positive women in discordant relationship were at highest risk for sexual violence compared to HIV negative women in discordant unions, and HIV negative women in negative concordant unions. HIV negative women in discordant relationships and those in concordant negative relationships showed no increased risk for sexual violence. However, couples' HIV

  20. Conjoined twins: scientific cinema and Pavlovian physiology.

    Science.gov (United States)

    Krementsov, Nikolai

    2015-01-01

    Through the lens of a 1957 documentary film, "Neural and humoral factors in the regulation of bodily functions (research on conjoined twins)," produced by the USSR Academy of Medical Sciences, this essay traces the entwined histories of Soviet physiology, studies of conjoined twins and scientific cinema. It examines the role of Ivan Pavlov and his students, including Leonid Voskresenkii, Dmitrii Fursikov and Petr Anokhin, in the development of "scientific film" as a particular cinematographic genre in Soviet Russia and explores numerous puzzles hidden behind the film's striking visuals.