The Truth-Default, Diagnostic Utility, and the Value of Contextual Knowledge in Deceptive Interactions

This dissertation describes and reports an experimental study examining the predictions of truth-default theory (TDT). TDT is an expansive, modular theory of deception detection which explains the processes by which people abandon the truth-default state and navigate judgments of message veracity in conversations. The first goal of this study was to test TDT’s seventh proposition, which explains how communicators abandon the truth-default state through trigger events (i.e., actions which prompt communicators to be uncertain about the accuracy of the message) such as decreased sender believability and message coherence. The second goal of this study was to test the predictions of TDT’s ninth hypothesis, which explains how messages are judged as deceptive through the same triggers that prompt the abandonment of the truth-default state. Finally, this study tests TDT’s twelfth proposition, which claims that questioning which produces diagnostic utility will ultimately result in higher judgment accuracy than relying on perceptions of sender believability or message coherence when judging the veracity of messages. The proposed study sampled 361 participants from Amazon’s Mechanical Turk (MTurk), who watched a sequence of two videos and completed an anonymous online survey. None of the study hypotheses concerning TDT’s seventh, ninth, and twelfth propositions were supported, but the findings from this dissertation did contribute to the deception literature with regard to the prevalence of the truth-default and truth bias. Theoretical and practical implications of the results are discussed, as well as a review of the limitations influencing the interpretation of this dissertation’s findings

Disappearing Messages: Privacy or Piracy?

Disappearing messages is an optional feature available in popular applications for more privacy. The Telegram instant messenger application is a rival and alternative to the popular messaging application WhatsApp, with both applications citing end-to-end encryption for both messages and calls as a key offering. While Telegram doesn’t officially have a ‘disappearing message’ feature like WhatsApp it still is possible to send disappearing messages using the secret chat functionality. In this paper, we analyse and evaluate ‘disappearing messages’ across Telegram and Snapchat to see whether they can be forensically preserved and/or recovered across Apple and Android operating systems. As these messages could be vital to investigations, with potential evidence and intelligence stored on them, not to mention the limited timeframe in which they are ‘viewable’ to the user, it is a great opportunity for digital forensic analysts to understand how they are stored, managed, and ‘deleted’ compared to traditional messages on the same platforms/applications

Forensic analysis of ephemeral messaging applications: disappearing messages or evidential data?

Ephemeral messaging or ‘disappearing messages’ is the mobile-to-mobile transmission of multimedia messages that automatically disappear from the recipient's screen after the message has been viewed. This new feature can be enabled by users for more privacy when using instant messaging apps. A user can set messages to disappear within a certain timeframe: 24 hours, 7 days, or 90 days, after the time they are sent. While disappearing messages provide additional privacy to users, its anti-forensics capability creates challenges for investigators in the recovery of evidential artefacts that could be crucial to an investigation. In this paper, we conduct a comprehensive forensic analysis of ‘disappearing messages’ across different digital platforms (mobile, desktop, and cloud) and instant messaging apps (WhatsApp, Snapchat, and Telegram) to determine whether they can be recovered within a limited timeframe. The results from this study provide valuable information to investigators dealing with instant messaging apps that have this feature enabled and provides detailed understanding of how disappearing messages are stored, managed, and deleted compared to messages sent without this feature enabled

Immunoglobulin signal transduction guides the specificity of B cell-T cell interactions and is blocked in tolerant self-reactive B cells.

The specificity of antibody (Ab) responses depends on focusing helper T (Th) lymphocyte signals to suitable B lymphocytes capable of binding foreign antigens (Ags), and away from nonspecific or self-reactive B cells. To investigate the molecular mechanisms that prevent the activation of self-reactive B lymphocytes, the activation requirements of B cells specific for the Ag hen egg lysozyme (HEL) obtained from immunoglobulin (Ig)-transgenic mice were compared with those of functionally tolerant B cells isolated from Ig-transgenic mice which also express soluble HEL. To eliminate the need for surface (s)Ig-mediated Ag uptake and presentation and allow the effects of sIg signaling to be studied in isolation, we assessed the ability of allogeneic T cells from bm12 strain mice to provide in vivo help to C57BL/6 strain-transgenic B cells. Interestingly, non-tolerant Ig-transgenic B cells required both allogeneic Th cells and binding of soluble HEL for efficient activation and Ab production. By contrast, tolerant self-reactive B cells from Ig/HEL double transgenic mice responded poorly to the same combination of allogeneic T cells and soluble HEL. The tolerant B cells were nevertheless normally responsive to stimulation with interleukin 4 and anti-CD40 Abs in vitro, suggesting that they retained the capacity to respond to mediators of T cell help. However, the tolerant B cells exhibited a proximal block in the sIg signaling pathway which prevented activation of receptor-associated tyrosine kinases in response to the binding of soluble HEL. The functional significance of this sIg signaling defect was confirmed by using a more potent membrane-bound form of HEL capable of triggering sIg signaling in tolerant B cells, which markedly restored their ability to collaborate with allogeneic Th cells and produce Ab. These findings indicate that Ag-specific B cells require two signals for mounting a T cell-dependent Ab response and identify regulation of sIg signaling as a mechanism for controlling self-reactive B cells

The Heritage of a Life: Robert Stipe, 1928-2007

The Carolina Planning Journal, the UNC Department of City and Regional Planning, and the broader planning community join preservationists from Chapel Hill, this state, and indeed around the country in remembering the remarkable life and far-reaching career of Robert Stipe, who died this past September. Stipe was certainly a pioneer in the field of conservation and historic preservation. From his base in Chapel Hill, he worked to legitimize the field and establish procedures and standards for preservation at the local, state, and federal levels. His edited volumes are used as university textbooks, while the ordinances and statutes he authored have enabled towns to preserve their past through historic district zoning. However, Stipe’s professional legacy is impossible to disentangle from the personal one, for he left an impact on the field not just through his writings, but also through his relationships of collaboration and mentoring. Four reflections here testify to Stipe’s commitment to preservation and to people. Myrick Howard provides an overview of Robert Stipe’s career and influence over more than one generation of students who went on to positions of leadership in land use, design, and preservation law. Weiming Lu writes in a more personal vein, as a fellow master’s student with Stipe in Regional Planning at UNC in the 1950s. Milton Heath describes the variety of ways that these friends and colleagues collaborated over the years. Finally, conversations with Stipe’s wife Josie and his son Fred provided the basis for an explanation of his motivations for dedicating his energies to historic preservation long before it was fashionable. The thread running through each piece is the radical idea, born in Robert Stipe as a young man and carried throughout an unexpectedly long life, to use the law to protect and enhance the landscape and design of cities and towns

Social contexts of remission from DSM-5 alcohol use disorder in a high-risk sample

BACKGROUND: Measures of social context, such as marriage and religious participation, are associated with remission from alcohol use disorders (AUDs) in population-based and treatment samples, but whether these associations hold among individuals at high familial risk for AUD is unknown. This study tests associations of measures of social context and treatment with different types of remission from DSM-5 AUD in a high-risk sample. METHODS: Subjects were 686 relatives of probands (85.7% first-degree) who participated in a high-risk family study of alcohol dependence. All subjects met criteria for AUD at baseline and were re-interviewed 5 years later. Follow-up status was categorized as persistent AUD, high-risk drinking, remitted low-risk drinking, and abstinence. Social context measures were defined as stable or changing from baseline to follow-up, and their bivariate and multivariate associations with follow-up status were tested. RESULTS: At follow-up, 62.8% of subjects had persistent AUD, 6.4% were high-risk drinkers, 22.2% were remitted low-risk drinkers, and 8.6% were abstinent. Birth of first child during the interval was the only measure of social context associated with remitted low-risk drinking and was significant for women only. Abstinent remission was characterized by being stably separated or divorced for women, new marriage for both sexes, experiencing low levels of family support and high levels of friend support, and receiving treatment. High-risk drinkers were more likely than individuals with persistent AUD to have a stable number of children and to have been recently unemployed. CONCLUSIONS: The social contexts accompanying different types of remission in this high-risk sample resemble those found in population-based and clinical samples. Low-risk drinkers resemble natural remitters from population-based samples who change their drinking habits with life transitions. Abstainers resemble clinical samples in marital context, support from friends, and treatment. High-risk drinkers appear to continue to experience negative consequences of heavy drinking

Organic vs. functional neurological disorders: The role of childhood psychological trauma

Although the relationship between psychological trauma and medically unexplained symptoms (MUS) is well established, this relationship is less well understood in people with medically unexplained neurological symptoms. In the present study, we set out to compare people with functional neurological disorders, and organic neurological disorders, in terms of childhood and adulthood traumatic events, traumatic stress, emotional dysregulation and symptoms of depression and anxiety. We have hypothesised that those with functional neurological disorders would be more likely to report childhood and adulthood traumatic life events, traumatic symptomatology, emotional dysregulation and symptoms of anxiety and depression, compared to those with organic neurological disorders. Sample consisted of a consecutive series of people with functional neurological disorders and with organic neurological disorders (n = 82) recruited from a hospital in Scotland. Participants completed measures of life events, traumatic stress, emotional regulation, anxiety and depression. The two groups were found to significantly differ in relation to all measures, with the MUS group being more likely to report childhood and adulthood life events, more severe emotional dysregulation, traumatic stress and symptoms of anxiety and stress. Logistic regression analysis revealed that exposure to childhood traumatic life events, specifically childhood sexual abuse, and childhood physical neglect, were the only factors which were significantly associated with membership of the medically unexplained neurological symptoms group. Although further research is required to confirm our findings, our results suggest that identifying and addressing the impact of childhood trauma, may alleviate distress and aid recovery from functional neurological disorders

Gravitational waves from high-power twisted light

Recent advances in high-energy and high-peak-power laser systems have opened up new possibilities for fundamental physics research. In this work, the potential of twisted light for the generation of gravitational waves in the high frequency regime is explored for the first time. Focusing on Bessel beams, novel analytic expressions and numerical computations for the generated metric perturbations and associated powers are presented. Compelling evidence is provided that the properties of the generated gravitational waves, such as frequency, polarisation states and direction of emission, are controllable by the laser pulse parameters and optical arrangements