Toward an automated signature recognition toolkit for mission operations

Signature recognition is the problem of identifying an event or events from its time series. The generic problem has numerous applications to science and engineering. At NASA's Johnson Space Center, for example, mission control personnel, using electronic displays and strip chart recorders, monitor telemetry data from three-phase electrical buses on the Space Shuttle and maintain records of device activation and deactivation. Since few electrical devices have sensors to indicate their actual status, changes of state are inferred from characteristic current and voltage fluctuations. Controllers recognize these events both by examining the waveform signatures and by listening to audio channels between ground and crew. Recently the authors have developed a prototype system that identifies major electrical events from the telemetry and displays them on a workstation. Eventually the system will be able to identify accurately the signatures of over fifty distinct events in real time, while contending with noise, intermittent loss of signal, overlapping events, and other complications. This system is just one of many possible signature recognition applications in Mission Control. While much of the technology underlying these applications is the same, each application has unique data characteristics, and every control position has its own interface and performance requirements. There is a need, therefore, for CASE tools that can reduce the time to implement a running signature recognition application from months to weeks or days. This paper describes our work to date and our future plans

Early Adversity and the Prospective Prediction of Depressive and Anxiety Disorders in Adolescents

The current study was a prospective exploration of the specificity of early childhood adversities as predictors of anxiety and depressive disorders in adolescents. Participants were 816 adolescents (414 males, 402 females) with diagnostic information collected at age 15; information on early adversities had been collected from the mothers during pregnancy, at birth, age 6 months, and age 5 years for a related study. Adolescents with "pure" anxiety disorders were compared with adolescents with "pure" depressive disorders (major depressive disorder, dysthymia), and these groups were compared to never-ill controls. Analyses controlled for gender and maternal depression and anxiety disorders. Results indicated that adolescents with anxiety disorders were more likely than depressed youth to have been exposed to various early stressors, such as maternal prenatal stress, multiple maternal partner changes, and more total adversities, whereas few early childhood variables predicted depressive disorders. Even when current family stressors at age 15 were controlled, early adversity variables again significantly predicted anxiety disorders. Results suggest that anxiety disorders may be more strongly related to early strees exposure, while depressive disorders may be related to more proximal stressors or to early stressors not assessed in the current study

The Effects of Mothers' Depression on the Behavioral Assessment of Disruptive Child Behavior

This study uses a group design to compare depressed and non-depressed mothers and their disruptive children. It controls for broad environmental stress factors to examine whether specific differences between groups can be linked with mothers’ depression. It aims to build a more comprehensive picture of depressed mothers’ interactions with their disruptive children by comparing these interactions with those of similar, but non-maternally depressed mother-child dyads, and a non-clinic control group

Differential exposure and reactivity to interpersonal stress predict sex differences in adolescent depression

This study tested the hypothesis that higher rates of depression in adolescent girls are explained by their greater exposure and reactivity to stress in the interpersonal domain in a large sample of 15-year-olds. Findings indicate that adolescent girls experienced higher levels of total and interpersonal episodic stress, whereas boys experienced higher levels of chronic stress (academic and close friendship domains). Higher rates of depression in girls were explained by their greater exposure to total stress, particularly interpersonal episodic stress. Adolescent girls were also more reactive (more likely to become depressed) to both total and interpersonal episodic stress. The findings suggest that girls experience higher levels of episodic stress and are more reactive to these stressors, increasing their likelihood of becoming depressed compared to boys. Results were discussed in terms of girls' greater interpersonal focus and implications for understanding sex differences in depression

Understanding the sex difference in vulnerability to adolescent depression: an examination of child and parent characteristics

This study examined sex differences in risk factors associated with adolescent depression in a large sample of boys and girls. Moderation and mediation explanatory models of the sex difference in likelihood of depression were examined. Findings indicate that the factors associated with depression in adolescent boys and girls are quite similar. All of the variables considered were associated with depression, but sex did not moderate the impact of vulnerability factors on likelihood of depression diagnosis. However, negative self-perceptions in the domains of achievement, global self-worth, and physical appearance partially mediated the relationship between sex and depression. Further, girls had higher levels of positive self-perceptions in interpersonal domains that acted as suppressors and reduced the likelihood of depression in girls. These findings suggest that girls' higher incidence of depression is due in part to their higher levels of negative self-perceptions, whereas positive interpersonal factors serve to protect them from depressive episodes

Stress sensitization and adolescent depressive severity as a function of childhood adversity: A link to anxiety disorders

The goal of the present study was to determine whether exposure to adversity in childhood contributes to a differential threshold at which stressful life events provoke depressive reactions in adolescence. In addition, to address empirical and conceptual questions about stress effects, the moderating effect of anxiety disorder history was also explored. This examination was conducted in a sample of 816 children of depressed and nondepressed mothers, who were followed from birth to age 15. Information on adversities experienced in childhood was collected both from mothers during the first five years of their youth's life and from the youths themselves at age 15, and included information on the mother's relationship with her partner, maternal psychopathology, as well as youth-reported abuse. Results indicated that youths with both greater exposure to adversity in childhood and a history of an anxiety disorder displayed increased depressive severity following low levels of episodic stress compared to youths with only one or neither of these risk factors. The results are speculated to reflect the possibility that early anxiety disorders associated with exposure to adversity in childhood may be a marker of dysregulated stress responses, and may help to account for the comorbidity of depression and anxiety in some individuals

The Effects of Sex-Role Attitudes and Group Composition on Men and Women in Groups

The dual impact of group gender composition and sex-role attitudes on self-perceptions and social behavior was explored. Androgynous and stereotyped men and women were placed in groups of skewed sex composition. Subjects\u27 self-descriptions of masculine attributes shifted significantly in the group environment. In some instances, sex role-stereotyped subjects responded most stereotypically when their gender was in the minority in the group. Differences between men and women and between androgynous and stereotyped subjects in sex role-related preferences for group roles and discussion topics were also found