11 research outputs found
Heterotic Cosmic Strings
We show that all three conditions for the cosmological relevance of heterotic
cosmic strings, the right tension, stability and a production mechanism at the
end of inflation, can be met in the strongly coupled M-theory regime. Whereas
cosmic strings generated from weakly coupled heterotic strings have the well
known problems posed by Witten in 1985, we show that strings arising from
M5-branes wrapped around 4-cycles (divisors) of a Calabi-Yau in heterotic
M-theory compactifications, solve these problems in an elegant fashion.Comment: 25 pages, v2: section and references adde
Multi-ancestry genome-wide association study of 21,000 cases and 95,000 controls identifies new risk loci for atopic dermatitis
Genetic association studies have identified 21 loci associated with atopic dermatitis risk predominantly in populations of European ancestry. To identify further susceptibility loci for this common, complex skin disease, we performed a meta-analysis of >15 million genetic variants in 21,399 cases and 95,464 controls from populations of European, African, Japanese and Latino ancestry, followed by replication in 32,059 cases and 228,628 controls from 18 studies. We identified ten new risk loci, bringing the total number of known atopic dermatitis risk loci to 31 (with new secondary signals at four of these loci). Notably, the new loci include candidate genes with roles in the regulation of innate host defenses and T cell function, underscoring the important contribution of (auto)immune mechanisms to atopic dermatitis pathogenesis
Genetic determinants of telomere length from 109,122 ancestrally diverse whole-genome sequences in TOPMed
Genetic studies on telomere length are important for understanding age-related diseases. Prior GWAS for leukocyte TL have been limited to European and Asian populations. Here, we report the first sequencing-based association study for TL across ancestrally-diverse individuals (European, African, Asian and Hispanic/Latino) from the NHLBI Trans-Omics for Precision Medicine (TOPMed) program. We used whole genome sequencing (WGS) of whole blood for variant genotype calling and the bioinformatic estimation of telomere length in n=109,122 individuals. We identified 59 sentinel variants (p-value OBFC1indicated the independent signals colocalized with cell-type specific eQTLs for OBFC1 (STN1). Using a multi-variant gene-based approach, we identified two genes newly implicated in telomere length, DCLRE1B (SNM1B) and PARN. In PheWAS, we demonstrated our TL polygenic trait scores (PTS) were associated with increased risk of cancer-related phenotypes
Investigation of Perceptions of Mathematics Teachers toward Calculators and the Implementation of Calculators
The explanatory correlational research study examined the degree of the relationships between the three elements and teachers' implementation of calculators in the mathematics classroom. The three elements include teachers' attitude toward technology, teachers' instructional use of calculators, and teachers' attitude toward calculators. An online survey created for the study was pilot tested, revised, and then used for data collection. This study investigated the perceptions of 33 secondary teachers in the Math Forum's electronic discussion groups during the 2010 - 2011 school year. Collected data were analyzed using SPSS 19.0 software to examine descriptive statistics and frequencies regarding teachers' attitude toward technology, instructional use, attitude toward calculators, and calculator implementation resulting in the identification of a perceived need for relevant training targeting calculators and calculator curriculum. The Spearman rank order was used to measure the relationships between the variables in this study. Using a significance level of .05, the rejection of the first null hypothesis indicated a significant relationship between teachers' attitude toward technology and teachers' implementation of calculators in the classroom (Spearman's rho = .717, p = .002). With a Spearman rank order correlation coefficient .717 (p = .002), there was enough evidence to say that a significant correlation exists between teachers' attitude toward instructional use of calculators and teachers' implementation of calculators in the mathematics classroom at the .05 level. The correlation between teachers' attitude toward calculators and teachersâ implementation of calculators was statistically significant at the .05 level (Spearman's rho = .506, p = .046)
Recommended from our members
Multiancestry association study identifies new asthma risk loci that colocalize with immune-cell enhancer marks.
We examined common variation in asthma risk by conducting a meta-analysis of worldwide asthma genome-wide association studies (23,948 asthma cases, 118,538 controls) of individuals from ethnically diverse populations. We identified five new asthma loci, found two new associations at two known asthma loci, established asthma associations at two loci previously implicated in the comorbidity of asthma plus hay fever, and confirmed nine known loci. Investigation of pleiotropy showed large overlaps in genetic variants with autoimmune and inflammatory diseases. The enrichment in enhancer marks at asthma risk loci, especially in immune cells, suggested a major role of these loci in the regulation of immunologically related mechanisms
The impact of risk management measures on the concentrations of per- and polyfluoroalkyl substances in source and treated drinking waters in Ontario, Canada
Recommended from our members
Multi-ethnic genome-wide association study of 21,000 cases and 95,000 controls identifies new risk loci for atopic dermatitis
Genetic association studies have identified 21 loci associated with atopic dermatitis risk predominantly in populations of European ancestry. To identify further susceptibility loci for this common complex skin disease, we performed a meta-analysis of >15 million genetic variants in 21,399 cases and 95,464 controls from populations of European, African, Japanese and Latino ancestry, followed by replication in 32,059 cases and 228,628 controls from 18 studies. We identified 10 novel risk loci, bringing the total number of known atopic dermatitis risk loci to 31 (with novel secondary signals at 4 of these). Notably, the new loci include candidate genes with roles in regulation of innate host defenses and T-cell function, underscoring the important contribution of (auto-)immune mechanisms to atopic dermatitis pathogenesis
Recommended from our members
Genetic determinants of telomere length from 109,122 ancestrally diverse whole-genome sequences in TOPMed
Genetic studies on telomere length are important for understanding age-related diseases. Prior GWAS for leukocyte TL have been limited to European and Asian populations. Here, we report the first sequencing-based association study for TL across ancestrally-diverse individuals (European, African, Asian and Hispanic/Latino) from the NHLBI Trans-Omics for Precision Medicine (TOPMed) program. We used whole genome sequencing (WGS) of whole blood for variant genotype calling and the bioinformatic estimation of telomere length in n=109,122 individuals. We identified 59 sentinel variants (p-value <5Ă10-9) in 36 loci associated with telomere length, including 20 newly associated loci (13 were replicated in external datasets). There was little evidence of effect size heterogeneity across populations. Fine-mapping at OBFC1 indicated the independent signals colocalized with cell-type specific eQTLs for OBFC1 (STN1). Using a multi-variant gene-based approach, we identified two genes newly implicated in telomere length, DCLRE1B (SNM1B) and PARN. In PheWAS, we demonstrated our TL polygenic trait scores (PTS) were associated with increased risk of cancer-related phenotypes
Pregnancy and neonatal outcomes of COVID -19: coreporting of common outcomes from PAN-COVID and AAP-SONPM registries
Objective
Few large cohort studies have reported data on maternal, fetal, perinatal and neonatal outcomes associated with severe acute respiratory syndrome coronavirus 2 (SARSâCoVâ2) infection in pregnancy. We report the outcome of infected pregnancies from a collaboration formed early during the pandemic between the investigators of two registries, the UK and Global Pregnancy and Neonatal outcomes in COVIDâ19 (PANâCOVID) study and the American Academy of Pediatrics (AAP) Section on NeonatalâPerinatal Medicine (SONPM) National Perinatal COVIDâ19 Registry.
Methods
This was an analysis of data from the PANâCOVID registry (1 January to 25 July 2020), which includes pregnancies with suspected or confirmed maternal SARSâCoVâ2 infection at any stage in pregnancy, and the AAPâSONPM National Perinatal COVIDâ19 registry (4 April to 8 August 2020), which includes pregnancies with positive maternal testing for SARSâCoVâ2 from 14âdays before delivery to 3âdays after delivery. The registries collected data on maternal, fetal, perinatal and neonatal outcomes. The PANâCOVID results are presented overall for pregnancies with suspected or confirmed SARSâCoVâ2 infection and separately in those with confirmed infection.
Results
We report on 4005 pregnant women with suspected or confirmed SARSâCoVâ2 infection (1606 from PANâCOVID and 2399 from AAPâSONPM). For obstetric outcomes, in PANâCOVID overall and in those with confirmed infection in PANâCOVID and AAPâSONPM, respectively, maternal death occurred in 0.5%, 0.5% and 0.2% of cases, early neonatal death in 0.2%, 0.3% and 0.3% of cases and stillbirth in 0.5%, 0.6% and 0.4% of cases. Delivery was preterm (<â37âweeks' gestation) in 12.0% of all women in PANâCOVID, in 16.1% of those women with confirmed infection in PANâCOVID and in 15.7% of women in AAPâSONPM. Extreme preterm delivery (<â27âweeks' gestation) occurred in 0.5% of cases in PANâCOVID and 0.3% in AAPâSONPM. Neonatal SARSâCoVâ2 infection was reported in 0.9% of all deliveries in PANâCOVID overall, in 2.0% in those with confirmed infection in PANâCOVID and in 1.8% in AAPâSONPM; the proportions of neonates tested were 9.5%, 20.7% and 87.2%, respectively. The rates of a smallâforâgestationalâage (SGA) neonate were 8.2% in PANâCOVID overall, 9.7% in those with confirmed infection and 9.6% in AAPâSONPM. Mean gestationalâageâadjusted birthâweight Zâscores were â0.03 in PANâCOVID and â0.18 in AAPâSONPM.
Conclusions
The findings from the UK and USA registries of pregnancies with SARSâCoVâ2 infection were remarkably concordant. Preterm delivery affected a higher proportion of women than expected based on historical and contemporaneous national data. The proportions of pregnancies affected by stillbirth, a SGA infant or early neonatal death were comparable to those in historical and contemporaneous UK and USA data. Although maternal death was uncommon, the rate was higher than expected based on UK and USA population data, which is likely explained by underascertainment of women affected by milder or asymptomatic infection in pregnancy in the PANâCOVID study, although not in the AAPâSONPM study. The data presented support strong guidance for enhanced precautions to prevent SARSâCoVâ2 infection in pregnancy, particularly in the context of increased risks of preterm delivery and maternal mortality, and for priority vaccination of pregnant women and women planning pregnancy. Copyright © 2021 ISUOG. Published by John Wiley & Sons Ltd
Multiancestry association study identifies new asthma risk loci that colocalize with immune-cell enhancer marks
We examined common variation in asthma risk by conducting a meta-analysis of worldwide asthma genome-wide association studies (23,948 asthma cases, 118,538 controls) of individuals from ethnically diverse populations. We identified five new asthma loci, found two new associations at two known asthma loci, established asthma associations at two loci previously implicated in the comorbidity of asthma plus hay fever, and confirmed nine known loci. Investigation of pleiotropy showed large overlaps in genetic variants with autoimmune and inflammatory diseases. The enrichment in enhancer marks at asthma risk loci, especially in immune cells, suggested a major role of these loci in the regulation of immunologically related mechanisms