General Relativity in Electrical Engineering

In electrical engineering metamaterials have been developed that offer unprecedented control over electromagnetic fields. Here we show that general relativity lends the theoretical tools for designing devices made of such versatile materials. Given a desired device function, the theory describes the electromagnetic properties that turn this function into fact. We consider media that facilitate space-time transformations and include negative refraction. Our theory unifies the concepts operating behind the scenes of perfect invisibility devices, perfect lenses, the optical Aharonov-Bohm effect and electromagnetic analogs of the event horizon, and may lead to further applications

Sleep-amount differentially affects fear-processing neural circuitry in pediatric anxiety: A preliminary fMRI investigation

Insufficient sleep, as well as the incidence of anxiety disorders, both peak during adolescence. While both conditions present perturbations in fear-processing-related neurocircuitry, it is unknown whether these neurofunctional alterations directly link anxiety and compromised sleep in adolescents. Fourteen anxious adolescents (AAs) and 19 healthy adolescents (HAs) were compared on a measure of sleep amount and neural responses to negatively valenced faces during fMRI. Group differences in neural response to negative faces emerged in the dorsal anterior cingulate cortex (dACC) and the hippocampus. In both regions, correlation of sleep amount with BOLD activation was positive in AAs, but negative in HAs. Follow-up psychophysiological interaction (PPI) analyses indicated positive connectivity between dACC and dorsomedial prefrontal cortex, and between hippocampus and insula. This connectivity was correlated negatively with sleep amount in AAs, but positively in HAs. In conclusion, the presence of clinical anxiety modulated the effects of sleep-amount on neural reactivity to negative faces differently among this group of adolescents, which may contribute to different clinical significance and outcomes of sleep disturbances in healthy adolescents and patients with anxiety disorders

Accepted for the Council:

for form and content and recommend that it be accepte

AN EXPLORATION OF AUDIENCE INVOLVEMENT WITHIN THE ELECTRONIC FAN CULTURE OF THE INTERNET

ii DEDICATION To the memory of my grandmother Antonietta Lemucchi, 1903-1996. Born in Trento, Italy, she was simply Nonna to those who knew her. Nonna left behind a rich legacy of love to many people who were fortunate enough to be touched by her kindness, wisdom, and zest for life. iii ACKNOWLEDGMENTS It is difficult to adequately convey the depth of my gratitude to the many people who participated in this project by virtue of their generous support and encouragement. At the top of the list are my wife Beth and our four children, Sarah, Lydia, Samuel, and Thomas. Thank you for your enduring patience and for surrounding me with your love, prayers, and encouragement. I wish to also thank the members of my dissertation committee for their wisdom and council throughout my research. A special portion of my gratitude goes to Dr. Benjamin Bates for taking me under his wings and keeping me ever focused on the principles of good theory and research. There have been countless others wh

Exploring parenting contexts of Latinx 2-to-5-year old children\u27s sleep: Qualitative evidence informing intervention development

Purpose: Poor sleep quality is associated with childhood obesity, and Latinx children have the highest prevalence of obesity in the United States. Parents are key agents to ensuring good sleep quality among children, but limited research has examined sleep parenting among Latinx working parents who may have added responsibilities. Design and methods: Working Latinx parents of 2-to-5-year old children participated in in-depth interviews exploring parenting and familial contexts of child sleep. Main topics in the interview guide included sleep-related parenting practices, social support, cultural influences, and intervention service delivery and content preferences. Thematic analysis was used to analyze data. Results: Twenty parents completed the interview. The following themes emerged: Sleep parenting, sleep knowledge, impact of familial structures, family commitments, child temperament, and broader contextual factors on sleep, and intervention content and design ideas. Across participants, employment was reported to be a barrier to effective sleep parenting. Parents also reported engaging in practices that may interfere with sleep quality such as using screen time as a distraction and reducing naptime during the weekends to increase the amount of family time. Family-level factors such as co-parenting and spousal support were reported to facilitate sleep parenting. Participants also indicated the need for more sleep parenting knowledge and a preference for mobile platforms and social media to deliver information. Conclusions: Results not only fill critical gaps in the literature, but also highlight the variability in parents\u27 approaches to sleep parenting and an urgent need for intervention/programming efforts to target Latinx parent\u27s sleep knowledge and parenting

Sleep Deprivation and Stressors: Evidence for Elevated Negative Affect in Response to Mild Stressors When Sleep Deprived

Stress often co-occurs with inadequate sleep duration, and both are believed to impact mood and emotion. It is not yet known whether inadequate sleep simply increases the intensity of subsequent stress responses or interacts with stressors in more complicated ways. To address this issue, we investigated the effects of one night of total sleep deprivation on subjective stress and mood in response to low-stress and high-stress cognitive testing conditions in healthy adult volunteers in two separate experiments (total N ϭ 53). Sleep was manipulated in a controlled, laboratory setting and stressor intensity was manipulated by changing difficulty of cognitive tasks, time pressure, and feedback about performance. Sleep-deprived participants reported greater subjective stress, anxiety, and anger than rested controls following exposure to the low-stressor condition, but not in response to the high-stressor condition, which elevated negative mood and stress about equally for both sleep conditions. These results suggest that sleep deprivation lowers the psychological threshold for the perception of stress from cognitive demands but does not selectively increase the magnitude of negative affect in response to high-stress performance demands