Quantifying the Reliability of Latent Fingerprint Matching via Signal Detection Theory

The definition of standards in fingerprint identification is currently an issue of discussion in the field. Quantitative standards have been used in the past to provide justifications for conclusions; however, a scientific basis for relying on numerical standards alone currently does not exist. The tradeoff for this combined approach is that conclusions are based on a conclusion that is left to the judgment of the examiner and may not be repeatable. To test the implementation of thresholds for conclusion, this research studied the effects of only considering concrete data in quantitative form. In this case, signal detection theory is applied to latent fingerprint matching by using automated fingerprint identification systems from two different program vendors. By searching a test set of fingerprints multiple times with a wide range of detail entered, values for the number of system-matched minutiae and computed match scores can be studied to determine threshold limits based on the amount of the search returns. This in turn allows for the generation of receiver operating characteristic curves that directly measure the reliability of the system. The results show that the ability of the system to distinguish matches and non-matches properly is partly based on the method by which the searches are evaluated. Furthermore, the searched area of the fingerprint and the size of the database play roles in determining how well the system is able to discriminate between states. Through future comparison against results submitted by latent fingerprint examiners, inferences can be drawn as to the reliability of conclusions based on varying levels of available detail

Performance of a circular body earth-to-orbit winged transport with various strap-on boosters

Various types of twin strap-on boosters were evaluated by applying them to a core vehicle. The core vehicle has a clipped delta wing and a simple circular body, and is equipped with five Space Shuttle main engines. The only propellants in the core vehicle are liquid oxygen and liquid hydrogen. The strap-on boosters investigated include the current Shuttle solid rocket motors with steel cases and advanced solids with graphite composite filament-wound cases. Also, two types of liquid-oxygen/hydrocarbon boosters were investigated - one pair without crossfeed to the core vehicle and one with. The payloads obtained were tabulated for various assumptions, such as power levels on the core vehicle engines, number of engines, and maximum allowable flight dynamic pressures. The payload for the core vehicle with two filament-wound Shuttle solid rocket strap-on boosters was 83,000 lb and the payload for two liquid strap-ons with crossfeed was 84,000 lb. The core vehicle with Shuttle solid rocket strap-on boosters is regarded as a near term technology system

Quantification of depth of anesthesia by nonlinear time series analysis of brain electrical activity

We investigate several quantifiers of the electroencephalogram (EEG) signal with respect to their ability to indicate depth of anesthesia. For 17 patients anesthetized with Sevoflurane, three established measures (two spectral and one based on the bispectrum), as well as a phase space based nonlinear correlation index were computed from consecutive EEG epochs. In absence of an independent way to determine anesthesia depth, the standard was derived from measured blood plasma concentrations of the anesthetic via a pharmacokinetic/pharmacodynamic model for the estimated effective brain concentration of Sevoflurane. In most patients, the highest correlation is observed for the nonlinear correlation index D*. In contrast to spectral measures, D* is found to decrease monotonically with increasing (estimated) depth of anesthesia, even when a "burst-suppression" pattern occurs in the EEG. The findings show the potential for applications of concepts derived from the theory of nonlinear dynamics, even if little can be assumed about the process under investigation.Comment: 7 pages, 5 figure

Technology-Based Communication and the Development of Interpersonal Competencies Within Adolescent Romantic Relationships: A Preliminary Investigation

This study investigated longitudinal associations between adolescents’ technology-based communication and the development of interpersonal competencies within romantic relationships. A school-based sample of 487 adolescents (58% girls; Mage = 14.1) participated at two time points, one year apart. Participants reported (1) proportions of daily communication with romantic partners via traditional modes (in person, on the phone) versus technological modes (text messaging, social networking sites) and (2) competence in the romantic relationship skill domains of negative assertion and conflict management. Results of cross-lagged panel models indicated that adolescents who engaged in greater proportions of technology-based communication with romantic partners reported lower levels of interpersonal competencies one year later, but not vice versa; associations were particularly strong for boys

Adolescent Susceptibility to Peer Influence in Sexual Situations

One consistent predictor of adolescents’ engagement in sexual risk behavior is their belief that peers are engaging in similar behavior; however, not all youth are equally susceptible to these peer influence effects. Understanding individual differences in susceptibility to peer influence is critical to identifying adolescents at risk for negative health outcomes. The purpose of this project was to identify predictors of susceptibility to peer influence using a novel performance-based measure of sexual risk-taking

An Online Growth Mindset Intervention in a Sample of Rural Adolescent Girls

Background. Students living in rural areas of the United States exhibit lower levels of educational attainment than their suburban counterparts. Innovative interventions are needed to close this educational gap. Aims. We investigated whether an online growth mindset intervention could be leveraged to promote academic outcomes. Sample. We tested the mindset intervention in a sample of 222 10th-grade adolescent girls (M age=15.2; 38% White, 25% Black, 29% Hispanic) from four rural, low-income high schools in Southeastern United States. Methods. We conducted a randomized controlled trial to test the efficacy of the growth mindset intervention, relative to a sexual health programme. We used random sampling and allocation procedures to assign girls to either the mindset intervention (n-115) or an attention-matched control programme (n-107). We assessed participants at pre-test, immediate post-test, and 4-month follow up. Results. Relative to the control condition, students assigned to the mindset intervention reported stronger growth mindsets at immediate post-test and 4-month follow up. Although the intervention did not have a total effect on academic attitudes or grades, it indirectly increased motivation to learn, learning efficacy and grades via the shifts in growth mindsets. Conclusions. Results indicate that this intervention is a promising method to encourage growth mindsets in rural adolescent girls

Randomized Trial of a Single-Session Growth Mind-Set Intervention for Rural Adolescents’ Internalizing and Externalizing Problems

Objective. Adolescents living in rural regions of the United States face substantial barriers to accessing mental health services, creating needs for more accessible, non-stigmatizing, briefer interventions. Research suggests that single-session “growth mindset” interventions (GM-SSIs)—which teach the belief that personal traits are malleable through effort—may reduce internalizing and externalizing problems in adolescents. However, GM-SSIs have not been evaluated among rural youth, and their effects on internalizing and externalizing problems have not been assessed within a single trial, rendering their relative benefits for different problem types unclear. We examined whether a computerized GM-SSI could reduce depressive symptoms, social anxiety symptoms, and conduct problems in adolescent girls from rural areas of the U.S. Method. Tenth-grade girls (N=222, M age=15.2, 38% white, 25% Black, 29% Hispanic) from four rural, low-income high schools in the Southeastern United States were randomized to receive a 45-minute GM-SSI or a computer-based, active control program, teaching healthy sexual behaviors. Girls self-reported depression symptoms, social anxiety symptoms, and conduct problem behaviors at baseline and four-month follow-up. Results. Relative to girls in the control group, girls receiving the GM-SSI reported modest but significantly greater reductions in depressive symptoms (d=.23) and likelihood of reporting elevated depressive symptoms (d=.29) from baseline to follow-up. GM-SSI effects were nonsignificant for social anxiety symptoms, although a small effect size emerged in the hypothesized direction (d=.21), and nonsignificant for change in conduct problems (d=.01). Conclusions. A free-of-charge, 45-minute GM-SSI may help reduce internalizing distress, especially depression—but not conduct problems—in rural adolescent girls

Experimentally measured susceptibility to peer influence and adolescent sexual behavior trajectories: A preliminary study.

A performance-based measure of peer influence susceptibility was examined as a moderator of the longitudinal association between peer norms and trajectories of adolescents' number of sexual intercourse partners. Seventy-one 9th grade adolescents (52% female) participated in an experimental “chat room” paradigm involving “e-confederates” who endorsed sexual risk behaviors. Changes in participants' responses to risk scenarios before versus during the “chat room” were used as a performance-based measure of peer influence susceptibility. Participants reported their perceptions of popular peers' number of sexual intercourse partner sat baseline, and self-reported their number of sexual intercourse partners at baseline and 6, 12, and 18 months later. Susceptibility was examined as a moderator of the longitudinal association between perceptions of popular peers' number of sexual intercourse partners and trajectories of adolescents' own numbers of partners. High perceptions of the number of popular peers' sexual intercourse partners combined with high peer influence susceptibility predicted steeper longitudinal trajectories of adolescents' number of partners. Results provide novel preliminary evidence regarding the importance of peer influence susceptibility in adolescents' development of sexual behaviors

Wavelet analysis of epileptic spikes

Interictal spikes and sharp waves in human EEG are characteristic signatures of epilepsy. These potentials originate as a result of synchronous, pathological discharge of many neurons. The reliable detection of such potentials has been the long standing problem in EEG analysis, especially after long-term monitoring became common in investigation of epileptic patients. The traditional definition of a spike is based on its amplitude, duration, sharpness, and emergence from its background. However, spike detection systems built solely around this definition are not reliable due to the presence of numerous transients and artifacts. We use wavelet transform to analyze the properties of EEG manifestations of epilepsy. We demonstrate that the behavior of wavelet transform of epileptic spikes across scales can constitute the foundation of a relatively simple yet effective detection algorithm.Comment: 4 pages, 3 figure