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The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
Description: Semiconductor physics contains a rich body of theory and working designs. However, their material properties seem to be reaching their limits. Perovskite oxides on the other hand have abundant physical properties, but are still under active investigation. The advent of RHEED-monitoring of pulsed laser deposition allows for the fabrication of structures with single unit cell (4 Å) thick layers. In this way we may be able to fabricate quantum well structures for both applications and fundamental investigations. Superlattices of the Mott insulator LaTiO3 (LTO) and the band gap insulator SrTiO3 (STO) form such a structure. The superlattices are metallic, both as-grown and post-annealed . This has been attributed to the existence of metallic states at the interfaces between LTO and STO . At these interfaces the electron density is found to extend about 10 Å into the STO. However, theoretically, the required length scale for quantum confinement is of the order of 4 Å. A possible way to increase this confinement is to use a buffer material with a larger band gap than that of LTO (similar to semiconductor band gap engineering) and/or with a lower dielectric constant . LaAlO3 (LAO) is such a material (ΔELAO = 5.6 eV vs. ΔESTO = 3.2 eV, εLAO = 24 vs. εSTO = 300). Here we report on the growth of LTO/LAO superlattices on STO substrates. As-grown superlattices of LTO/LAO are metallic, while post-annealing turns them insulating. This may be explained from a disorder-order transition in a 2D Mott-Hubbard model . XPS and EELS measurements of the titanium valence show interesting differences for LTO layers close to and far away from the sample surface. The former, for thin LAO capping layers, show the presence of Ti4+ while the latter only have Ti3+. Hard XPS of samples with varying capping layer thickness shows an exponential dependence of the Ti3+ contents on a length scale of about 5 unit cells.  A. Ohtomo et al., Nature 419, 378-380 (2002).  S. Okamoto & A.J. Millis, Phys. Rev. B 70, 075101 (2004).  D. Heidarian & N. Trivedi, Phys. Rev. Lett. 93, 126401 (2004).
There is a growing concern about the role of the environment in the dissemination of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARG). In this systematic review, we summarize evidence for increases of ARG in the natural environment associated with potential sources of ARB and ARG such as agricultural facilities and wastewater treatment plants. A total of 5247 citations were identified, including studies that ascertained both ARG and ARB outcomes. All studies were screened for relevance to the question and methodology. This paper summarizes the evidence only for those studies with ARG outcomes (n = 24). Sixteen studies were at high (n = 3) or at unclear (n = 13) risk of bias in the estimation of source effects due to lack of information or failure to control for confounders. Statistical methods were used in nine studies; three studies assessed the effect of multiple sources using modeling approaches, and none reported effect measures. Most studies reported higher ARG concentration downstream/near the source, but heterogeneous findings hindered making any sound conclusions. To quantify increases of ARG in the environment due to specific point sources, there is a need for studies that emphasize analytic or design control of confounding, and that provide effect measure estimates.
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
Kuratite, ideally Ca4(Fe2+10Ti2)O4[Si8Al4O36], the Fe2+-analogue of rhönite and a new member of the sapphirine supergroup, was identified from the D'Orbigny angrite meteorite by electron microscopy and micro-Raman spectroscopy. Based on the least-squares refinement of 25 d-spacings measured from selected-area electron diffraction patterns of 11 zone axes, the symmetry of kuratite was shown to be triclinic (space group by analogy to rhönite) with a = 10.513(7), b = 10.887(7), c = 9.004(18) Å, α = 105.97(13), β = 96.00(12), γ = 124.82(04)°, V = 767 ± 2 Å3 and Z = 1 for the 40 oxygen formula. The empirical formula based on eight electron microprobe analyses is (Ca3.88Na0.02REE3+0.03Mn0.03Mg0.01Ni0.02Zn0.01Sr0.01)∑4.01 (Fe2+9.989.9Ti2.00)∑11.98(Si7.80Al3.52Fe3+0.64P0.05S0.02)∑12.03O39.98F0.01Cl0.01. The simplified formula is Ca4(Fe2+10Ti2)O4[Si8Al4O36]. Micro-Raman spectroscopy showed four main bands resembling those of lunar rhönite but with higher frequencies due to different chemical composition. Analogous to the occurrence of kuratite in terrestrial basaltic rocks, kuratite coexisting with Al, Ti-bearing hedenbergite, ulvöspinel, iron-sulfide, tsangpoite, Ca-rich fayalite and kirschsteinite in D'Orbigny angrite most probably was formed at >1000°C by rapid cooling of an interstitial melt, which is subsilicic, almost Mg-free but enriched in Al-P-Ca-Ti-Fe.
This is the first cross-national study of intermittent explosive disorder (IED).
A total of 17 face-to-face cross-sectional household surveys of adults were conducted in 16 countries (n = 88 063) as part of the World Mental Health Surveys initiative. The World Health Organization Composite International Diagnostic Interview (CIDI 3.0) assessed DSM-IV IED, using a conservative definition.
Lifetime prevalence of IED ranged across countries from 0.1 to 2.7% with a weighted average of 0.8%; 0.4 and 0.3% met criteria for 12-month and 30-day prevalence, respectively. Sociodemographic correlates of lifetime risk of IED were being male, young, unemployed, divorced or separated, and having less education. The median age of onset of IED was 17 years with an interquartile range across countries of 13–23 years. The vast majority (81.7%) of those with lifetime IED met criteria for at least one other lifetime disorder; co-morbidity was highest with alcohol abuse and depression. Of those with 12-month IED, 39% reported severe impairment in at least one domain, most commonly social or relationship functioning. Prior traumatic experiences involving physical (non-combat) or sexual violence were associated with increased risk of IED onset.
Conservatively defined, IED is a low prevalence disorder but this belies the true societal costs of IED in terms of the effects of explosive anger attacks on families and relationships. IED is more common among males, the young, the socially disadvantaged and among those with prior exposure to violence, especially in childhood.
Investigations on the relationship between sweet taste perception and body mass index (BMI) have been inconclusive. Here, we report a longitudinal analysis using a genetically informative sample of 1,576 adolescent Australian twins to explore the relationship between BMI and sweet taste. First, we estimated the phenotypic correlations between perception scores for four different sweet compounds (glucose, fructose, neohesperidine dihydrochalcone (NHDC), and aspartame) and BMI. Then, we computed the association between adolescent taste perception and BMI in early adulthood (reported 9 years later). Finally, we used twin modeling and polygenic risk prediction analysis to investigate the genetic overlap between BMI and sweet taste perception. Our findings revealed that BMI in early adulthood was significantly associated with each of the sweet perception scores, with the strongest correlation observed in aspartame with r = 0.09 (p = .007). However, only limited evidence of association was observed between sweet taste perception and BMI that was measured at the same time (in adolescence), with the strongest evidence of association observed for glucose with a correlation coefficient of r = 0.06 (p = .029) and for aspartame with r = 0.06 (p = .035). We found a significant (p < .05) genetic correlation between glucose and NHDC perception and BMI. Our analyses suggest that sweet taste perception in adolescence can be a potential indicator of BMI in early adulthood. This association is further supported by evidence of genetic overlap between the traits, suggesting that some BMI genes may be acting through biological pathways of taste perception.
Although mental disorders are significant predictors of educational attainment throughout the entire educational career, most research on mental disorders among students has focused on the primary and secondary school years.
The World Health Organization World Mental Health Surveys were used to examine the associations of mental disorders with college entry and attrition by comparing college students (n = 1572) and non-students in the same age range (18–22 years; n = 4178), including non-students who recently left college without graduating (n = 702) based on surveys in 21 countries (four low/lower-middle income, five upper-middle-income, one lower-middle or upper-middle at the times of two different surveys, and 11 high income). Lifetime and 12-month prevalence and age-of-onset of DSM-IV anxiety, mood, behavioral and substance disorders were assessed with the Composite International Diagnostic Interview (CIDI).
One-fifth (20.3%) of college students had 12-month DSM-IV/CIDI disorders; 83.1% of these cases had pre-matriculation onsets. Disorders with pre-matriculation onsets were more important than those with post-matriculation onsets in predicting subsequent college attrition, with substance disorders and, among women, major depression the most important such disorders. Only 16.4% of students with 12-month disorders received any 12-month healthcare treatment for their mental disorders.
Mental disorders are common among college students, have onsets that mostly occur prior to college entry, in the case of pre-matriculation disorders are associated with college attrition, and are typically untreated. Detection and effective treatment of these disorders early in the college career might reduce attrition and improve educational and psychosocial functioning.
The pulsar wind nebula (PWN) surrounding the 50-ms pulsar B0540-69 in the Large Magellanic Cloud shares many properties with the Crab Nebula, the canonical Galactic PWN. We have used the ACIS instrument on the Chandra X-ray Observatory to perform spatially resolved spectroscopy of the PWN. The spectrum of the inner 10″ is characterized by a simple power law, with a spectral index that steepens strongly with radius. Outside the central 10″ the spectra also require a thermal component. This diameter corresponds to a shell detected in [OIII], suggesting that this shell represents a skin around the PWN, in analogy to the Crab. We infer the value of several key PWN parameters, including σ, the average ratio of electromagnetic to particle flux.
Eustachian tube dysfunction is a disorder for which there are limited medical and surgical treatments. Recently, eustachian tube balloon dilation has been proposed as a potential solution.
A systematic literature review was performed. Abstracts were selected for relevance, and pooled data analysis and qualitative analysis was conducted.
Nine prospective studies, describing 713 eustachian tube balloon dilations in 474 patients (aged 18–86 years), were identified. Follow-up duration ranged from 1.5 to 18 months. Ability to perform a Valsalva manoeuvre improved from 20 to 177 out of 245 ears following eustachian tube balloon dilation and, where data were reported in terms of patient numbers, from 15 to 189 out of 210 patients. Tympanograms were classified as type A in 7 out of 141 ears pre-operatively and in 86 out of 141 ears post-operatively.
Prospective case series can confirm the safety of eustachian tube balloon dilation. As a potential solution for chronic eustachian tube dysfunction, further investigations are warranted to establish a higher level of evidence of efficacy.
We present a synoptic study of active galactic nuclei (AGN) detected by EUVE. We also present complementary ROSAT PSPC spectra for these sources and for other AGN in directions of low galactic absorption. It is found that the best-fit power-law photon indices of the X-ray spectra at 0.1–2.4 keV are anti-correlated with their galactic hydrogen columns. The indices for the 0.9–2.4 keV range do not show such a correlation, and are considerably smaller (i.e. flatter). We discuss a number of possible interpretations of this correlation but only one of these, the presence of a partially ionized absorbing gas in the AGN, explains the observations satisfactorily. The ubiquity of this effect suggests that this component be may very common in AGN.
We report EUVE spectral and photometric data of the Seyfert 1 galaxy MRK 279. The photometric data show large amplitude variations over time scales less than 10,000 s. The spectrum is characterized by several features between 80 and 100 Å. We compare the observed data with several models. We can rule out the possibility that the EUV emission is from a diffuse corona or intercloud medium. Models that assume the soft X-ray/EUV emission results from reprocessing in an optical BLR region are also inconsistent with the data. A collisional excitation model is consistent with the observations but requires a cloud density ≥ 1011 cm−3.
To determine the functional integrity of the neural systems involved in emotional responding/regulation and response control/inhibition in youth (age 10–18 years) with disruptive behavioral disorders (DBDs: conduct disorder and/or oppositional defiant disorder) as a function of callous-unemotional (CU) traits.
Twenty-eight healthy youths and 35 youths with DBD [high CU (HCU), n = 18; low CU (LCU), n = 17] performed the fMRI Affective Stroop task. Participants viewed positive, neutral, and negative images under varying levels of cognitive load. A 3-way ANOVA (group×emotion by task) was conducted on the BOLD response data.
Youth with DBD-HCU showed significantly less activation of ventromedial prefrontal cortex (vmPFC) and amygdala in response to negative stimuli, compared to healthy youth and youth with DBD-LCU. vmPFC responsiveness was inversely related to CU symptoms in DBD. Youth with DBD-LCU showed decreased functional connectivity between amygdala and regions including inferior frontal gyrus in response to emotional stimuli. Youth with DBD (LCU and HCU) additionally showed decreased insula responsiveness to high load (incongruent trials) compared to healthy youth. Insula responsiveness was inversely related to ADHD symptoms in DBD.
These data reveal two forms of pathophysiology in DBD. One associated with reduced amygdala and vmPFC responses to negative stimuli and related to increased CU traits. Another associated with reduced insula responses during high load task trials and related to ADHD symptoms. Appropriate treatment will need to be individualized according to the patient's specific pathophysiology.
The Charlson comorbidity index (CCI) is widely used for control of confounding from comorbidities in epidemiological studies. International Classification of Diseases (ICD)-coded diagnoses from administrative hospital databases is potentially an efficient way of deriving CCI. However, no studies have evaluated its validity in infectious disease research. We aim to compare CCI derived from administrative data and medical record review in predicting mortality in patients with infections. We conducted a cross-sectional study on 199 inpatients. Correlation analyses were used to compare comorbidity scores from ICD-coded administrative databases and medical record review. Multivariable regression models were constructed and compared for discriminatory power for 30-day in-hospital mortality. Overall agreement was fair [weighted kappa 0·33, 95% confidence interval (CI) 0·23–0·43]. Kappa coefficient ranged from 0·17 (95% CI 0·01–0·36) for myocardial infarction to 0·85 (95% CI 0·59–1·00) for connective tissue disease. Administrative data-derived CCI was predictive of CCI ⩾5 from medical record review, controlling for age, gender, resident status, ward class, clinical speciality, illness severity, and infection source (C = 0·773). Using the multivariable model comprising age, gender, resident status, ward class, clinical speciality, illness severity, and infection source to predict 30-day in-hospital mortality, administrative data-derived CCI (C = 0·729) provided a similar C statistic as medical record review (C = 0·717, P = 0·8548). In conclusion, administrative data-derived CCI can be used for assessing comorbidities and confounding control in infectious disease research.
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
The perception of sweetness varies among individuals but the sources of this variation are not fully understood. Here, in a sample of 1,901 adolescent and young adults (53.8% female; 243 MZ and 452 DZ twin pairs, 511 unpaired individuals; mean age 16.2 ± 2.8, range 12–26 years), we studied the variation in the perception of sweetness intensity of two monosaccharides and two high-potency sweeteners: glucose, fructose, neohesperidine dihydrochalcone (NHDC), and aspartame. Perceived intensity for all sweeteners decreased with age (2–5% per year) and increased with the history of otitis media (6–9%). Males rated aspartame slightly stronger than females (7%). We found similar heritabilities for sugars (glucose: h2 = 0.31, fructose: h2 = 0.34) and high-potency sweeteners (NHDC: h2 = 0.31, aspartame: h2 = 0.30); all were in the modest range. Multivariate modeling showed that a common genetic factor accounted for >75% of the genetic variance in the four sweeteners, suggesting that individual differences in perceived sweet intensity, which are partly due to genetic factors, may be attributed to a single set of genes. This study provided evidence of the shared genetic pathways between the perception of sugars and high-potency sweeteners.