Optimum phase noise reduction and repetition rate tuning in quantum-dot mode-locked lasers

Competing approaches exist, which allow control of phase noise and frequency tuning in mode-locked lasers, but no judgement of pros and cons based on a comparative analysis was presented yet. Here, we compare results of hybrid mode-locking, hybrid mode-locking with optical injection seeding, and sideband optical injection seeding performed on the same quantum dot laser under identical bias conditions. We achieved the lowest integrated jitter of 121 fs and a record large radio-frequency (RF) tuning range of 342 MHz with sideband injection seeding of the passively mode-locked laser. The combination of hybrid mode-locking together with optical injection-locking resulted in 240 fs integrated jitter and a RF tuning range of 167 MHz. Using conventional hybrid mode-locking, the integrated jitter and the RF tuning range were 620 fs and 10 MHz, respectively. © 2014 AIP Publishing LLC.

All-fiber 250 MHz fundamental repetition rate pulsed laser with tilted fiber grating polarizer

We demonstrated a high fundamental repetition-rate pulsed erbium-doped fiber laser with all-fiber-integrated configuration. A novel scheme using a 45°-tilted fiber grating as the in-fiber polarizing element was employed to shorten the total cavity length and, thus, increase the fundamental repetition rate of the laser. Dissipative soliton pulses mode-locked with a fundamental repetition rate of 251.3 MHz and pulse duration of 96.7 fs have been achieved from the compact and all-fiber ring cavity laser. Additionally, passively Q-switched pulses were observed from this high fundamental repetition-rate fiber laser, which is the first report on Q-switched fiber laser using a tilted fiber grating.

Wider-frequency combs generation, noise reduction, and repetition rate tuning in quantum-dot mode-locked lasers

We describe the technique allowing for generation of low-noise wider frequency combs and pulses of shorter duration in quantum-dot mode-locked lasers. We compare experimentally noise stabilization techniques in semiconductor modelocked lasers. We discuss the benefits of electrical modulation of the laser absorber voltage (hybrid mode-locking), combination of hybrid mode-locking with optical injection seeding from the narrow linewidth continues wave master source and optical injection seeding of two coherent sidebands separated by the laser repetition rate. © 2014 SPIE.

Non-verbal signalling in digital discourse:the case of letter repetition

This study focuses on the interactional functions of non-standard spelling, in particular letter repetition, used in text-based computer-mediated communication as a means of non-verbal signalling. The aim of this paper is to assess the current state of non-verbal cue research in computer-mediated discourse and demonstrate the need for a more comprehensive and methodologically rigorous exploration of written non-verbal signalling. The study proposes a contextual and usage-centered view of written paralanguage. Through illustrative, close linguistic analyses the study proves that previous approaches to non-standard spelling based on their relation to the spoken word might not account for the complexities of this CMC cue, and in order to further our understanding of their interactional functions it is more fruitful to describe the role they play during the contextualisation of the verbal messages. The interactional sociolinguistic approach taken in the analysis demonstrates the range of interactional functions letter repetition can achieve, including contribution to the inscription of socio-emotional information into writing, to the evoking of auditory cues or to a display of informality through using a relaxed writing style.

Effect of delay of first interview and repetition of interview on accuracy and confidence of recall of a flashbulb -type memory

Hearing of the news of the death of Diana, Princess of Wales, in a traffic accident, is taken as an analogue for being a percipient but uninvolved witness to a crime, or a witness to another person's sudden confession to some illegal act. This event (known in the literature as a “reception event”) has previously been hypothesized to cause one to form a special type of memory commonly known as a “flashbulb memory” (FB) (Brown and Kulik, 1977). FB's are hypothesized to be especially resilient against forgetting, highly detailed including peripheral details, clear, and inspiring great confidence in the individual for their accuracy. FB's are dependent for their formation upon surprise, emotional valence, and impact, or consequentiality to the witness of the initiating event. FB's are thought to be enhanced by frequent rehearsal. FB's are very important in the context of criminal investigation and litigation in that investigators and jurors usually place great store in witnesses, regardless of their actual accuracy, who claim to have a clear and complete recollection of an event, and who express this confidently. Therefore, the lives, or at least the freedom, of criminal defendants, and the fortunes of civil litigants hang on the testimony of witnesses professing to have FB's. ^ In this study, which includes a large and diverse sample (N = 305), participants were surveyed within 2–4 days after hearing of the fatal accident, and again at intervals of 2 and 4 weeks, 6, 12, and 18 months. Contrary to the FB hypothesis, I found that participants' FB's degraded over time beginning at least as early as two weeks post event. At about 12 months the memory trace stabilized, resisting further degradation. Repeated interviewing did not have any negative affect upon accuracy, contrary to concerns in the literature. Analysis by correlation and regression indicated no effect or predictive power for participant age, emotionality, confidence, or student status, as related to accuracy of recall; nor was participant confidence in accuracy predicted by emotional impact as hypothesized. Results also indicate that, contrary to the notions of investigators and jurors, witnesses become more inaccurate over time regardless of their confidence in their memories, even for highly emotional events. ^

Self-cutting and prospective repetition of self-harm: studies of emergency department presentations in Ireland

Background Self-harm places an individual at increased risk of future self-harm and suicide, and indicates distress and maladaptive coping. Those who present to hospital with self-cutting form a significant minority of self-harm patients who are at increased risk of prospective repetition of self-harm and suicide compared with those presenting with intentional overdose. In addition to increased risk, there is emerging evidence of demographic, psychological, clinical, and social differences between those presenting with self-cutting and those presenting with overdose. Aim and Key Objectives The aim of the current doctoral work was to examine in detail the association between presenting with self-cutting and risk of prospective repetition. The objectives were: to identify evidence-based risk factors for repetition of self-harm among those presenting to emergency departments with self-harm; to compare demographic and presentation characteristics and prospective repetition across presentations of self-cutting only, self-cutting plus intentional overdose, and intentional overdose only; to compare prospective repetition and other characteristics within self-cutting presentations based on the type of treatment received; to compare self-cutting and intentional overdose patients on psychological risk and protective factors for repetition; and to examine the lived experience of engaging in repeated overdose and self-cutting. Methods The current doctoral work used a mixed-methods approach and is comprised of one systematic review and four empirical studies. The empirical studies were two registry-based prospective studies of Irish hospital presentations of self-harm, one prospective structured interview study, and one qualitative study using Interpretative Phenomenological Analysis. Results The systematic review identified several consistent and emerging risk factors for repetition of self-harm, compared to which self-cutting had a medium-sized effect. The registry studies demonstrated that the involvement of self-cutting, particularly less medically severe selfcutting, confers an increased risk of 1-month and 12-month repetition among Irish index selfharm presentations. The structured psychological study detected higher hopelessness and lower non-reactivity to inner experience among those presenting with self-cutting, and higher depression among those who repeated self-harm. Repeaters had lower baseline levels of protective psychological factors than non-repeaters and continued to have higher depression and hopelessness at follow-up. Finally, the qualitative study indicated that self-harm is a purposeful action taken in response to an overwhelming situation and is evaluated afterwards in terms of personal and social effects. Chosen method of self-harm seemed to be influenced by the desired outcome of the self-harm act, capability, accessibility and previous experience. Conclusion Despite limitations in terms of recruitment rates, the work presented in this thesis is innovative in examining the issue of the association between self-cutting and repetition from multiple perspectives. No one factor can reliably predict all repetition but self-cutting represents one consistent and easily detected risk factor for repetition. Those who present with self-cutting exhibit significant differences on demographic, clinical, and psychological variables compared with those presenting with intentional overdose, and seem to exhibit a more vulnerable profile. However, those who present with self-cutting do not form a discrete or homogenous group, and self-harm methods and levels of suicidal intent are liable to fluctuate over time.

Feeling Bodies in Marketing: Aesthetics, Emotions and Gender

Gender is deeply embedded in marketing ideology, and it continues to be a topic of concern in the marketing academy. There is little attention paid by marketers, however, to related studies in other fields on aesthetic labour and emotional labour in relation to gender issues, despite the commonalities and intersections between them. This article seeks to incorporate aesthetic labour and emotional labour into the gender and marketing discussion. It concludes by calling for greater critical awareness of gender as a dominant motif in our ideologies, discourses and practices in marketing, offering suggestions for empirical research into this important topic.

Cold War Legacies: Systems, Theory, Aesthetics

From futures research, pattern recognition algorithms, nuclear waste disposal and surveillance technologies, to smart weapons systems, contemporary fiction and art, this book shows that we are now living in a world imagined and engineered during the Cold War. Drawing on theorists such as Jean Baudrillard, Jacques Derrida, Michel Foucault, Luce Irigaray, Friedrich Kittler, Michel Serres, Peter Sloterdijk, Carl Schmitt, Bernard Stiegler and Paul Virilio this collection makes connections between Cold War material and conceptual technologies, as they relate to the arts, society, and culture.

Reverberations: The Philosophy, Aesthetics, and Politics of Noise

A publication emerging out of a successful international conference I co-organised on noise in 2010. The first of two volumes, this one focuses on noise as an aesthetic, political and cultural concept, and a range of noise practices beyond purely sonic ones, such as audiovisual noise and noise in communication theory. It argues that noise is fundamental to contemporary communication practices and facilitates a reversal of perspective in how these practices can be understood

View-sensitive ERP repetition effects indicate automatic holistic processing of spatially unattended objects

This study examined the properties of ERP effects elicited by unattended (spatially uncued) objects using a short-lag repetition-priming paradigm. Same or different common objects were presented in a yoked prime-probe trial either as intact images or slightly scrambled (half-split) versions. Behaviourally, only objects in a familiar (intact) view showed priming. An enhanced negativity was observed at parietal and occipito-parietal electrode sites within the time window of the posterior N250 after the repetition of intact, but not split, images. An additional post-hoc N2pc analysis of the prime display supported that this result could not be attributed to differences in salience between familiar intact and split views. These results demonstrate that spatially unattended objects undergo visual processing but only if shown in familiar views, indicating a role of holistic processing of objects that is independent of attention.

The art of second wave positive psychology: Harnessing Zen aesthetics to explore the dialectics of flourishing

In recent years, a “second wave” of positive psychology has been emerging, characterised, above all, by an awareness and appreciation of the dialectical nature of flourishing. This paper offers a philosophical foundation for this second wave, based on Eastern philosophy, and, in particular, Zen aesthetics. Part one introduces Zen, including its key philosophical ideas and practices, as well as two antecedent traditions that helped to form it, namely, Buddhism and Taoism. Part two then elucidates three aesthetic principles that are integral to Zen: mono no aware (pathos of life), wabi-sabi (desolate beauty), and yūgen (profound grace). The paper discusses how these principles could be of value to positive psychology in fostering dialectical understanding and appreciation, thus highlighting future directions for the field.

Event-related potential effects of object repetition depend on attention and part-whole configuration

The effects of spatial attention and part-whole configuration on recognition of repeated objects were investigated with behavioral and event-related potential (ERP) measures. Short-term repetition effects were measured for probe objects as a function of whether a preceding prime object was shown as an intact image or coarsely scrambled (split into two halves) and whether or not it had been attended during the prime display. In line with previous behavioral experiments, priming effects were observed from both intact and split primes for attended objects, but only from intact (repeated same-view) objects when they were unattended. These behavioral results were reflected in ERP waveforms at occipital-temporal locations as more negative-going deflections for repeated items in the time window between 220 and 300 ms after probe onset (N250r). Attended intact images showed generally more enhanced repetition effects than split ones. Unattended images showed repetition effects only when presented in an intact configuration, and this finding was limited to the right-hemisphere electrodes. Repetition effects in earlier (before 200 ms) time-windows were limited to attended conditions at occipito-temporal sites (N1), a component linked to the encoding of object structure, while repetition effects at central locations during the same time window (P150) were found only from objects repeated in the same intact configuration—both previously attended and unattended probe objects. The data indicate that view-generalization is mediated by a combination of analytic (part-based) representations and automatic view-dependent representations.

Postdigital play and the aesthetics of recruitment

This paper analyses reconfigurations of play in newly emergent material and digital configurations of game design. It extends recent work examining dimensions of hybridity in playful products by turning attention to interfaces, practices and spaces, rather than devices. We argue that the concept of hybrid play relies on predefining clear and distinct entities that then enter into hybrid situations. Drawing on concepts of the ‘interface’ and ‘postdigital’, we argue the distribution of computing devices creates difficulties for such presuppositions. Instead, we propose an ‘aesthetic of recruitment’ that is adequate to the new openness of social and technical play.