Statistical Analysis of Molecular Signal Recording

A molecular device that records time-varying signals would enable new approaches in neuroscience. We have recently proposed such a device, termed a “molecular ticker tape”, in which an engineered DNA polymerase (DNAP) writes time-varying signals into DNA in the form of nucleotide misincorporation patterns. Here, we define a theoretical framework quantifying the expected capabilities of molecular ticker tapes as a function of experimental parameters. We present a decoding algorithm for estimating time-dependent input signals, and DNAP kinetic parameters, directly from misincorporation rates as determined by sequencing. We explore the requirements for accurate signal decoding, particularly the constraints on (1) the polymerase biochemical parameters, and (2) the amplitude, temporal resolution, and duration of the time-varying input signals. Our results suggest that molecular recording devices with kinetic properties similar to natural polymerases could be used to perform experiments in which neural activity is compared across several experimental conditions, and that devices engineered by combining favorable biochemical properties from multiple known polymerases could potentially measure faster phenomena such as slow synchronization of neuronal oscillations. Sophisticated engineering of DNAPs is likely required to achieve molecular recording of neuronal activity with single-spike temporal resolution over experimentally relevant timescales.United States. Defense Advanced Research Projects Agency. Living Foundries ProgramGoogle (Firm)New York Stem Cell Foundation. Robertson Neuroscience Investigator AwardNational Institutes of Health (U.S.) (EUREKA Award 1R01NS075421)National Institutes of Health (U.S.) (Transformative R01 1R01GM104948)National Institutes of Health (U.S.) (Single Cell Grant 1 R01 EY023173)National Institutes of Health (U.S.) (Grant 1R01DA029639)National Institutes of Health (U.S.) (Grant 1R01NS067199)National Science Foundation (U.S.) (CAREER Award CBET 1053233)National Science Foundation (U.S.) (Grant EFRI0835878)National Science Foundation (U.S.) (Grant DMS1042134)Paul G. Allen Family Foundation (Distinguished Investigator in Neuroscience Award

Cold Hardiness and Supercooling Capacity in the Overwintering Larvae of the Codling Moth, Cydia pomonella

The codling moth, Cydia pomonella L. (Lepidoptera: Tortricidae), a worldwide apple pest, is classified as a freeze-intolerant organism and one of the most cold-tolerant pests. The objectives of this study were to examine the supercooling point of overwintering and non-diapausing larvae of C. pomonella as an index of its cold hardiness, and to assess larval mortality following 24 h exposure to extreme low temperatures ranging from -5 to -25°C. The mean (±SE) supercooling point for feeding larvae (third through fifth instars) was -12.4 ± 1.1°C. The mean supercooling point for cocooned, non-diapausing larvae (i.e., non-feeding stages) decreased as the days that the arvae were cocooned increased and changed between -15.1 ± 1.2°C for one to two day cocooned arvae and -19.2 ± 1.8°C for less than five day cocooned larvae. The mean (±SE) supercooling point for other non-feeding stages containing pupae and overwintering larvae were -19.9 ± 1.0°C and -20.2 ± 0.2°C, respectively. Mean supercooling points of C. pomonella larvae were significantly lower during the winter months than the summer months, and sex had no effect on the supercooling point of C. pomonella larvae. The mortality of larvae increased significantly after individuals were exposed to temperatures below the mean supercooling point of the population. The supercooling point was a good predictor of cold hardiness

Developmental trajectories of child to adolescent externalizing behavior and adult DSM-IV disorder: results of a 24-year longitudinal study

Objective: Childhood externalizing behavior is found to be relatively persistent. Developmental pathways within types of externalizing behavior have been recognized from childhood to adolescence. We aimed to describe the prediction of adult DSM-IV disorders from developmental trajectories of externalizing behavior over a period of 24 years on a longitudinal multiple birth cohort study of 2,076 children. This has not been examined yet. Methods: Trajectories of the four externalizing behavior types aggression, opposition, property violations, and status violations were determined separately through latent class growth analysis (LCGA) using data of five waves, covering ages 4-18 years. Psychiatric disorders of 1,399 adults were assessed with the CIDI. We used regression analyses to determine the associations between children's trajectories and adults' psychiatric disorders. Results: All externalizing behavior types showed significant associations with disruptive disorder in adulthood. In all antisocial behavior types high-level trajectories showed the highest probability for predicting adult disorders. Particularly the status violations cluster predicted many disorders in adulthood. The trajectories most often predicted disruptive disorders in adulthood, but predicted also anxiety, mood, and substance use disorders. Conclusions: We can conclude that an elevated level of externalizing behavior in childhood has impact on the long-term outcome, regardless of the developmental course of externalizing behavior. Furthermore, different types of externalizing beh

The Association between Conduct Problems and the Initiation and Progression of Marijuana Use during Adolescence: A Genetic Analysis across Time

The present study used a prospective, longitudinal design to investigate genetic and environmental influences on the association between earlier conduct problems and the initiation and progression of marijuana use during adolescence. Parent- and teacher-reported conduct problems assessed at Time 1 (1996) and self-reported marijuana use assessed at Time 2 (2004) were available for 1088 adolescent twin pairs participating in the Cardiff Study of All Wales and North West of England Twins (CaStANET). Using a novel approach to the modeling of initiation and progression dimensions in substance use, findings suggested that the initiation of marijuana use in adolescence was influenced by genetic, common and unique environmental factors. The progression (or frequency) of marijuana use was influenced by genetic and unique environmental factors. Findings for conduct problems indicated that while the presence or absence of conduct problems was largely heritable, the relative severity of conduct problems appeared to be more strongly environmentally influenced. Multivariate model fitting indicated that conduct problems in childhood and early adolescence made a small but significant contribution to the risk for marijuana use 8 years later

An exploratory study of the relationship between parental attitudes and behaviour and young people's consumption of alcohol

Background Concern is growing regarding frequent and excessive misuse of alcohol by young people. The average age at which young people in Europe start to drink is twelve and a half, and during the last decade, the quantity of alcohol consumed by younger adolescents in the UK has increased. Families are known to play an important role in shaping young people's alcohol misuse, although family risk and protective factors associated with misuse in a UK context are in need of further investigation. Methods The study used a cross-sectional design, involving secondary analyses of self-completion questionnaire responses from 6,628 secondary school children (i.e. aged 11-16 years), from 12 schools within an urban location in Wales. Items relating to family functioning and perceived parental attitudes were first subjected to factor analysis. Associations of family closeness and conflict, parental monitoring and attitudes and family history of substance misuse with children's self reported alcohol consumption were examined using logistic regression analyses. Results Approximately three quarters of respondents reported having tried alcohol, most of whom had first tried alcohol aged 12 or under. Parental monitoring and family closeness were positively correlated with one another and were both associated with significantly lower levels of drinking behaviours. Family violence and conflict, more liberal parental attitudes towards substance use and towards alcohol and petty crime, and family history of substance misuse were positively correlated with one another and with higher levels of drinking behaviours. Parental monitoring was identified as the family functioning factor most consistently associated with drinking behaviour in multivariate analyses. Conclusions Significant relationships were found between young people's drinking behaviours and perceptions of risk and protective factors in the family environment. Parental monitoring was strongly associated with family closeness and appeared to form one part of a parenting style of more general communication and regulation of children's behaviour. Findings support the need for alcohol misuse prevention interventions which address risk and protective factors within the family setting. Timing of such prevention work should be related both to the development of family relationships and the age at which young people begin drinking alcohol

A Meta-analysis of Attachment to Parents and Delinquency

To investigate the link between attachment to parents and delinquency, and the potential moderating effects of age and sex, 74 published and unpublished manuscripts (N = 55,537 participants) were subjected to a multilevel meta-analysis. A mean small to moderate effect size was found (r = 0.18). Poor attachment to parents was significantly linked to delinquency in boys and girls. Stronger effect sizes were found for attachment to mothers than attachment to fathers. In addition, stronger effect sizes were found if the child and the parent had the same sex compared to cross-sex pairs of children and parents. Age of the participants moderated the link between attachment and delinquency: larger effect sizes were found in younger than in older participants. It can be concluded that attachment is associated with juvenile delinquency. Attachment could therefore be a target for intervention to reduce or prevent future delinquent behavior in juveniles

Verbal, Facial and Autonomic Responses to Empathy-Eliciting Film Clips by Disruptive Male Adolescents with High Versus Low Callous-Unemotional Traits

This study examined empathy-related responding in male adolescents with disruptive behavior disorder (DBD), high or low on callous-unemotional (CU) traits. Facial electromyographic (EMG) and heart rate (HR) responses were monitored during exposure to empathy-inducing film clips portraying sadness, anger or happiness. Self-reports were assessed afterward. In agreement with expectations, DBD adolescents with high CU traits showed significantly lower levels of empathic sadness than healthy controls across all response systems. Between DBD subgroups significant differences emerged at the level of autonomic (not verbal or facial) reactions to sadness, with high CU respondents showing less HR change from baseline than low CU respondents. The study also examined basal patterns of autonomic function. Resting HR was not different between groups, but resting respiratory sinus arrhythmia (RSA) was significantly lower in DBD adolescents with high CU traits compared to controls. Results support the notion that CU traits designate a distinct subgroup of DBD individuals

The Economic Maturity Gap Encourages Continuity in Offending

In the study of criminal careers, factors that predict continuity in offending are of importance to both theory and policy. One recently advanced hypothesis is Moffitt’s “economic maturity gap,” which argues that some adolescence-limited offenders may be mired in a poor economic situation. As only one study to date has examined this hypothesis, the current study seeks to extend this line of research by assessing the relationship of the economic maturity gap on later offending.Using data from the Cambridge Study in Delinquent Development, three distinct operationalizations of the economic maturity gap are used to predict continued offending into mid-adulthood.Findings support the hypothesis that adolescence-limited males who experience this gap in late adolescence are more likely to continue offending into adulthood.Experiencing poor economic circumstances helps to maintain offending into mid-adulthood