Reliabilities of redundant electrical generator systems

Reliability of redundant electrical generating system configurations for use in SNAP-2 AND SNAP-

Evaluation of a new trauma-related drinking to cope measure: Latent structure and heritability

Posttraumatic stress disorder (PTSD) and alcohol use disorder (AUD) commonly co-occur, share latent genetic risk, and are associated with many negative public health outcomes. Via a self-medication framework, trauma-related drinking to cope (TRD), an unexplored phenotype to date, may help explain why these two disorders co-occur, thus serving as an essential target for treatment and prevention efforts. This study sought to create a novel measure of TRD and to investigate its indirect influences on the association between PTSD and AUD, as well as its potential shared molecular genetic risk with PTSD in a genetically-informative study of college students. A sample of 1,896 undergraduate students with a history of trauma and alcohol use provided genotypic data and completed an online assessment battery. The psychometric properties of TRD and how it relates to relevant constructs were examined using descriptive statistics and structural equation modeling. Results of a correlated multiple mediator model indicated that, while accounting for the effects of generalized drinking motives, TRD partially mediated the relation between PTSD and alcohol use problems (β = 0.213, p \u3c .001), consistent with the self-medication hypothesis, and that this relationship was stronger for males (β = 0.804, p \u3c .001) than for females (β = 0.463, p \u3c .001). Results were substantiated using longitudinal data. Genotypic analyses to be presented will include univariate genome wide complex trait analyses (GCTA) to establish SNP-based heritability associated with TRD and PTSD, separately, as well as bivariate GCTA to examine potential overlap in heritability between TRD and PTSD.https://scholarscompass.vcu.edu/gradposters/1047/thumbnail.jp

Exploring Resilience Models in a Sample of Combat-Exposed Military Service Members and Veterans: A Comparison and Commentary

Background: The term resilience is applied in numerous ways in the mental health field, leading to different perspectives of what constitutes a resilient response and disparate findings regarding its prevalence following trauma. Objective: illustrate the impact of various definitions on our understanding and prevalence of resilience, we compared various resilience definitions (absence of PTSD, absence of current mental health diagnosis, absence of generalized psychological distress, and an alternative trauma load–resilience discrepancy model of the difference between actual and predicted distress given lifetime trauma exposure) within a combat-exposed military personnel and veteran sample. Method: In this combat-trauma exposed sample (N = 849), of which approximately half were treatment seeking, rates of resilience were determined across all models, the kappa statistic was used to determine the concordance and strength of association across models, and t-tests examined the models in relation to a self-reported resilience measure. Results: Prevalence rates were 43.7%, 30.7%, 87.4%, and 50.1% in each of the four models. Concordance analyses identified 25.7% (n = 218) considered resilient by all four models (kappa = .40, p \u3c .001). Correlations between models and self-reported resilience were strong, but did not fully overlap. Conclusions:The discussion highlights theoretical considerations regarding the impact of various definitions and methodologies on resilience classifications, links current findings to a systems-based perspective, and ends with suggestions for future research approaches on resilience

Prospective Longitudinal Study of the Pregnancy DNA Methylome: The US Pregnancy, Race, Environment, Genes (PREG) Study

Purpose The goal of the Pregnancy, Race, Environment, Genes study was to understand how social and environmental determinants of health (SEDH), pregnancy-specific environments (PSE) and biological processes influence the timing of birth and account for the racial disparity in preterm birth. The study followed a racially diverse longitudinal cohort throughout pregnancy and included repeated measures of PSE and DNA methylation (DNAm) over the course of gestation and up to 1 year into the postpartum period. Participants All women were between 18 and 40 years of age with singleton pregnancies and no diagnosis of diabetes or indication of assisted reproductive technology. Both mother and father had to self-identify as either African-American (AA) or European-American (EA). Maternal peripheral blood samples along with self-report questionnaires measuring SEDH and PSE factors were collected at four pregnancy visits, and umbilical cord blood was obtained at birth. A subset of participants returned for two additional postpartum visits, during which additional questionnaires and maternal blood samples were collected. The pregnancy and postpartum extension included n=240 (AA=126; EA=114) and n=104 (AA=50; EA=54), respectively. Findings to date One hundred seventy-seven women (AA=89, EA=88) met full inclusion criteria out of a total of 240 who were initially enrolled. Of the 63 participants who met exclusion criteria after enrolment, 44 (69.8%) were associated with a medical reason. Mean gestational age at birth was significantly shorter for the AA participants by 5.1 days (M=272.5 (SD=10.5) days vs M=277.6 (SD=8.3)). Future plans Future studies will focus on identifying key environmental factors that influence DNAm change across pregnancy and account for racial differences in preterm birth

“If you wanted me to speak your language then you should have stayed in your country”: a critical ethnography of linguistic identity and resiliency in the life of an Afghan refugee

Nasreen and her family had not wanted to leave their native Afghanistan, but when the Taliban’s violence forced them to seek refuge in Iran, Nasreen found herself a teenager on the outskirts of Tehran. Discrimination, lack of opportunity, and an unwelcoming environment compelled her to make the dangerous overland journey from Iran to Turkey along with her husband, her brother, and her two sons. Now, they have asylum in the United States, where Nasreen is thriving—earning a degree at a community college and translating for other members of her community. Refusing to dwell on the past and enduringly optimistic about the future, Nasreen has demonstrated remarkable resilience despite the tremendously difficult circumstances of forced migration. Based on several interviews with Nasreen, I have come to believe that her decision to maintain her heritage language has been a stabilizing force in her life and a key component of her resilience as a refugee, as a stranger, and as a mother. Functioning as both a symbolic and actual means of transnational connection, Nasreen’s use of her ethnic language is how she remains connected to her family back in Iran, who she desperately hopes will someday join her in the United States. In a life that has stretched across four countries and been dominated by circumstances beyond her control, her language choice is also how she claims agency over her identity. This stability, in turn, empowers Nasreen to cultivate a dual identity that allows her to acculturate into American society and maintain a cultural integrity that is coherent with her worldview and sense of self. Finally, Nasreen’s use of her mother tongue with her children—even though they refuse to speak it back—enables her to mother them in her most authentic way and to remain connected with them as they grow up in a culture vastly different from her own. This study will hopefully engender empathy and admiration for Nasreen and the millions of refugees like her who, despite immense adversity, somehow manage to thrive as strangers in a strange land, spirits intact

COMT Val(158)Met genotypes differentially influence subgenual cingulate functional connectivity in healthy females

Brain imaging studies have cons stently shown subgenual Anterior Cingulate Cortical (sgACC) involvement in emotion processing. catechol-O-methyltransferase (COMT) Val(158) and Met(158) polymorphisms may influence such emotional brain processes in specific ways. Given that resting-state fMRI (rsfMRI) may increase our understanding on brain functioning, we integrated genetic and rsfMRI data and focused on sgACC functional connections. No studies have yet investigated the influence of the COMT Val(158)Met polymorphism (rs4680) on sgACC resting-state functional connectivity (rsFC) in healthy individuals. A homogeneous group of 61 Caucasian right-handed healthy female university students, all within the same age range, underwent isfMRI. Compared to Met158 homozygotes, Val(158) allele carriers displayed significantly stronger rsFC between the sgACC and the left parahippocampal gyrus, ventromedial parts of the inferior frontal gyrus (IFG), and the nucleus accumbens (NAc). On the other hand, compared to Val(158) homozygotes, we found in Met(158) allele carriers stronger sgACC rsFC with the medial frontal gyrus (MEG), more in particular the anterior parts of the medial orbitofrontal cortex. Although we did not use emotional or cognitive tasks, our sgACC rsFC results point to possible distinct differences in emotional and cognitive processes between Val(158) and Met(158) allele carriers. Hovvever, the exact nature of these directions remains to be determined

Calculations of reliability predictions for the Apollo spacecraft

A new method of reliability prediction for complex systems is defined. Calculation of both upper and lower bounds are involved, and a procedure for combining the two to yield an approximately true prediction value is presented. Both mission success and crew safety predictions can be calculated, and success probabilities can be obtained for individual mission phases or subsystems. Primary consideration is given to evaluating cases involving zero or one failure per subsystem, and the results of these evaluations are then used for analyzing multiple failure cases. Extensive development is provided for the overall mission success and crew safety equations for both the upper and lower bounds

Corticotrophin-Releasing Hormone Type 1 Receptor Gene (CRHR1) Variants Predict Posttraumatic Stress Disorder Onset and Course in Pediatric Injury Patients

Posttraumatic stress disorder (PTSD) is a common and disabling anxiety disorder that may occur in the aftermath of exposure to potentially traumatic life events. PTSD is moderately heritable, but few specific molecular variants accounting for this heritability have been identified. Genes regulating the hypothalamic-pituitary-adrenal (HPA) axis, such as corticotrophin-releasing hormone type 1 receptor gene (CRHR1), have been implicated in traumatic-stress related phenotypes but have yet to be studied in relation to PTSD. The present study sought to examine the relation between 9 single nucleotide polymorphisms (SNPs) in the CRHR1 gene and posttraumatic stress symptoms in a prospective study of pediatric injury patients (n = 103) who were first assessed in the acute aftermath of their injury at the hospital. Results indicated that multiple SNPs were associated with acute symptoms at a univariate level, and after correction for multiple testing, rs12944712 was significantly related to acute PTSD symptoms. Longitudinal latent growth curve analyses suggest that rs12944712 is also related to both acute symptom level and trajectory of symptoms over time. The present study adds support for the role of CRHR1 in the stress response following potentially traumatic event exposure in youth. It should be noted that the sample size in this study was small, and therefore statistical power was low; following, results from this study should be considered preliminary. Although results are not definitive, the findings from this study warrant future replication studies on how variation in this gene relates to response to traumatic event exposure in youth