6,436 research outputs found

    Attosecond time-resolved photoelectron holography

    Get PDF
    Ultrafast strong-field physics provides insight into quantum phenomena that evolve on an attosecond time scale, the most fundamental of which is quantum tunneling. The tunneling process initiates a range of strong field phenomena such as high harmonic generation (HHG), laser-induced electron diffraction, double ionization and photoelectron holography—all evolving during a fraction of the optical cycle. Here we apply attosecond photoelectron holography as a method to resolve the temporal properties of the tunneling process. Adding a weak second harmonic (SH) field to a strong fundamental laser field enables us to reconstruct the ionization times of photoelectrons that play a role in the formation of a photoelectron hologram with attosecond precision. We decouple the contributions of the two arms of the hologram and resolve the subtle differences in their ionization times, separated by only a few tens of attoseconds

    Narrative, identity, and recovery from serious mental illness: A life history of a runner

    Get PDF
    In recent years, researchers have investigated the psychological effects of exercise for people with mental health problems, often by focusing on how exercise may alleviate symptoms of mental illness. In this article I take a different tack to explore the ways in which exercise contributed a sense of meaning, purpose, and identity to the life of one individual named Ben, a runner diagnosed with schizophrenia. Drawing on life history data, I conducted an analysis of narrative to explore the narrative types that underlie Ben's stories of mental illness and exercise. For Ben, serious mental illness profoundly disrupted a pre-existing athletic identity removing agency, continuity, and coherence from his life story. By returning to exercise several years later, Ben reclaimed his athletic identity and reinstated some degree of narrative agency, continuity, and coherence. While the relationships between narrative, identity, and mental health are undoubtedly complex, Ben's story suggests that exercise can contribute to recovery by being a personally meaningful activity which reinforces identity and sense of self

    Parent-child interaction in Nigerian families: conversation analysis, context and culture

    Get PDF
    This paper uses a conversation analysis (CA) approach to explore parent child interaction (PCI) within Nigerian families. We illustrate how speech and language therapists (SLTs), by using CA, can tailor recommendations according to the interactional style of each individual family that are consonant with the family’s cultural beliefs. Three parent-child dyads were videoed playing and talking together in their home environments. The analysis uncovered a preference for instructional talk similar to that used in the classroom. Closer examination revealed that this was not inappropriate when considering the context of the activities and their perceived discourse role. Furthermore, this was not necessarily at the expense of responsivity or semantic contingency. The preference for instructional talk appeared to reflect deeply held cultural beliefs about the role of adults and children within the family and it is argued that the cultural paradigm is vitally important to consider when evaluating PCI. Given a potential risk that such young children may be vulnerable in terms of language difficulties, we offer an example of how PCI can be enhanced to encourage language development without disrupting the naturally occurring talk or the underlying purpose of the interaction

    Longitudinal Evaluation of Sealing Molars with and without Incipient Dental Caries in a Public Health Program

    Full text link
    Objectives: This study undertook a retrospective evaluation of the effect of sealants on the caries experience of initially sound and incipient permanent first molar pit and fissure surfaces. Methods : Records of children with complete five-year records were obtained from a school-based dental sealant program in a fluoridated community. Sealants were placed on 677 tooth surfaces in 96 children; 120 tooth surfaces in 17 children who received baseline examinations were not sealed because of lack of caregiver consent. Tooth surfaces were initially diagnosed as being sound or having incipient lesions, and evaluated for caries status after five years. Results : For initially incipient surfaces the five-year decay rate was 10.8 percent (41 of 380 surfaces) for sealed surfaces and 51.8 percent (29 of 56 surfaces) for nonsealed surfaces with an odds ratio of 8.88 (95% Cl=4.56, 17.35). Initially sound surfaces had a decay rate of 8.1 percent (24 of 297 surfaces) for sealed surfaces and 12.5 percent (8 of 64 surfaces) for nonsealed surfaces with an odds ratio of 1.63 (95% Cl=0.63, 4.08). The two odds ratios were significantly different. Conclusions : Initially sound tooth surfaces were unlikely to become decayed in five years, and did not benefit greatly from the application of sealants. Within the limitations of this study, there were clear efficiencies in sealing incipient, but not sound, surfaces. The targeting of teeth with incipient caries for sealants is therefore recommended.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66270/1/j.1752-7325.1995.tb02358.x.pd

    Stretching and Bending the Frame – Green Possibilities in Popular Romantic Narratives

    Get PDF
    This article examines frame theory, popular culture, and environmental values. Reviewing frame theory across journalism, communication studies, linguistics, and fine art, it will examine in particular ‘cultural framing’. Radical thought is invariably associated with the avant-garde, yet narrative or genre innovations in popular culture can also trigger ‘deeper’ cognitive shifts, potentially transforming ‘common culture’. Citing comics, films, and animation, the main example is popular music and how Björk and British Sea Power have subverted generic and acoustic conventions (e.g. melody), and music’s habitual romantic narratives, to re-frame human–nonhuman relationships ecologically. By stretching and manipulating frames, popular culture can adapt and engender environmental narratives for mass consumption

    The influence of organizational social responsibility on involvement behavior in community sport membership associations

    Full text link
    Membership‐based associations are critical to their local communities and the overall social impact of the nonprofit sector. This study examines how organizational social responsibility within nonprofit membership associations influences positive member involvement behaviors, including volunteering, speaking positively about the club, and member loyalty. Self‐administered online questionnaires were completed by 735 members within seven grassroots membership associations in Ontario, Canada offering community‐based sport programs. Results show that members are somewhat aware of and felt positively about their organization’s socially responsible efforts. Awareness of these efforts had a positive direct effect on the involvement behaviors of members, including intention to stay involved with their club and speaking positively about their club to others (i.e., word of mouth). Members’ level of social consciousness was found to have a positive direct effect on word of mouth. Furthermore, members’ positive evaluation of sport clubs’ socially responsible initiatives was found to partially mediate the positive relationship between social consciousness and involvement behavior, as well as partially mediate the positive relationship between awareness of those efforts and involvement behavior. Results of this research provide grassroots membership associations with an in‐depth understanding of how their organization’s efforts toward social responsibility influence member perceptions and behaviors, which may help them focus their efforts and more effectively manage their social change agenda moving forward.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155505/1/nml21406_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155505/2/nml21406.pd

    Classical Logical versus Quantum Conceptual Thought: Examples in Economics, Decision theory and Concept Theory

    Full text link
    Inspired by a quantum mechanical formalism to model concepts and their disjunctions and conjunctions, we put forward in this paper a specific hypothesis. Namely that within human thought two superposed layers can be distinguished: (i) a layer given form by an underlying classical deterministic process, incorporating essentially logical thought and its indeterministic version modeled by classical probability theory; (ii) a layer given form under influence of the totality of the surrounding conceptual landscape, where the different concepts figure as individual entities rather than (logical) combinations of others, with measurable quantities such as 'typicality', 'membership', 'representativeness', 'similarity', 'applicability', 'preference' or 'utility' carrying the influences. We call the process in this second layer 'quantum conceptual thought', which is indeterministic in essence, and contains holistic aspects, but is equally well, although very differently, organized than logical thought. A substantial part of the 'quantum conceptual thought process' can be modeled by quantum mechanical probabilistic and mathematical structures. We consider examples of three specific domains of research where the effects of the presence of quantum conceptual thought and its deviations from classical logical thought have been noticed and studied, i.e. economics, decision theory, and concept theories and which provide experimental evidence for our hypothesis.Comment: 14 page
    • 

    corecore