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Authenticity is more than self-enhancement: behavioral and neurophysiological evidence
No full textNegative self-descriptive information can be threatening to the self. This may depend, however, on the self-representation for which the information is relevant. We focused on two self-presentations, the authentic self and the presented self. In particular, we examined how the authentic and presented selves are influenced by emotional self-descriptiveness. Participants (N = 147) completed a self-referent emotional Stroop task while EEG was recorded. They viewed in colored text positive or negative traits exemplifying the authentic self (“I am genuinely honest”), the presented self (“I am outwardly honest”), or control (“It is clearly honest”). Color naming latency was slower to negative (vs. positive) traits for the presented self and control. Color naming latency was faster to negative (vs. positive) traits for the authentic self. Event-related potentials indicated that at both early (P1) and later (P3) stages of attentional processing, the authentic self exhibited comparable amplitudes to negative and positive traits. However, P1 was larger for negative, and P3 was larger for positive, traits for the presented self. Taken together, the findings highlight that the presented self is more pursuant of positivity, whereas the authentic self is more tolerant of negativity
Reproducibility and alternative electrochemical methods for testing ORR/OER electrocatalysts
No full textScreening potential new electrocatalyst materials for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) performance is a crucial component for the advancement of energy storage and conversion devices. Drop casting catalyst inks onto a rotating disc/rotating ring disc electrode (RDE/RRDE) surface is a widely used screening method due to its speed and simplicity, however, it is highly sensitive to electrode preparation and measurement conditions which limits reproducibility and comparability across studies. The first section of this thesis systematically investigates the impact of three modifications to the drop casting procedure: the use of a heat lamp during drying, electrode rotation during drying, and the inclusion of IPA in the ink. Electrochemical performance and catalyst distribution were analysed with RRDE measurements and large area energy dispersive x-ray spectroscopy (EDS) mapping. The electrodes that were dried at rotation or with a heat lamp exhibited lower OER currents and smaller confidence deviations. EDS analysis showed rougher surfaces for IPA containing inks and the formation of concentrated rings of catalyst material on some rotated electrodes, with no electrode achieving uniform catalyst distribution. Contact angle measurements also showed lower angles for the electrodes dried without a heat lamp, rotation, or IPA.The second section introduces sampled current voltammetry (SCV) as a potential alternative catalyst screening technique due to the correlation between RDE/RRDE rotation rate and SCV sampling time. SCV applies a series of steps from a rest potential to a target potential and back to the rest potential again. Current transients are obtained at each target potential step which are then sampled at a specific time, the currents obtained at each target potential for a specific sampling time are then used to construct a sampled current voltammogram. A conditioning procedure is carried out between each target potential step to reduce the influence of electrode history compared to conventional potential sweeping techniques, this was adjusted to control the surface oxide coverage on platinum disc electrodes. Variations to the conditioning procedure upper potential limit (EUP) and rest potential (EREST) showed changes in SCV onset potential and current magnitude, linked to oxide coverage, and anion adsorption. These findings demonstrate SCV as a highly sensitive technique for studying electrode surface processes.The final section of this thesis investigates SCV on higher surface electrodes, including platinum black and electrodeposited transition metal oxides (TMOs). The magnitude of the SCV currents observed for the platinum black electrodes were all much higher than those observed in the rotating disc electrode voltammograms, consistent with utilisation of the full electrode surface area, compared to the geometric surface area considered in RDE. The next part of this chapter focused on electrodeposited TMOs on RDEs and stainless steel electrodes. Electrodes dried at 25°C showed better OER activity, whereas the 500°C dried depositions showed better ORR activity, all depositions showed small errors indicating high reproducibility. Comparison between RDE and SCV testing is complicated for larger surface area electrodes due to the differing surface sensitivities between the two techniques
Prevalence of childhood exposure to domestic violence in 10 low- and middle-income countries: Analysis of violence against children and youth survey data
No full textBackground: Childhood exposure to domestic violence and abuse (DVA) is associated with lasting impacts on child development, mental health, and future violence risk. However, global estimates are outdated, based largely on high-income countries, and often use inconsistent measures. This study provides updated prevalence estimates from 10 LMICs, using a standardized indicator of exposure.Objective: To generate updated, cross-national prevalence estimates of childhood exposure to DVA in LMICs using a consistent measurement approach.Participants and Setting: Nationally representative data were drawn from 10 Violence Against Children and Youth Surveys, conducted between 2013 and 2019 across Africa, Asia, Eastern Europe, and Latin America. Respondents aged 13-24 were asked retrospectively about witnessing or hearing physical violence between caregivers before age 18.Methods: Weighted prevalence estimates were calculated by sex and country based on responses to a standardized item. Country-specific population data were used to estimate the number of exposed individuals.Results: Prevalence ranged from 11.80% to 30.68%. In most countries, female respondents reported a higher prevalence of exposure than males. Across the 10 countries, an estimated 19.84 million adolescents and young adults were exposed to DVA before age 18. These figures represent 7.21% to 14.91% of UNICEF's 2006 global estimate, despite being derived from only 10 countries and a narrow definition of exposure.Conclusions: Childhood exposure to DVA remains widespread and under-recognized in LMICs, and global estimates substantially understate the scale of the issue. Improved surveillance using standardized, cross-culturally appropriate indicators is urgently needed to inform prevention, policy, and child protection efforts
Robust airline scheduling with turnaround under uncertainty: towards collaborative airline scheduling
No full textRobust airline scheduling fosters operational resilience in aviation by producing plans that remain feasible despite ensuing disruptions. This paper analyses the airline scheduling process, including flight scheduling, fleet assignment, aircraft routing, and crew pairing. It examines how previous studies optimise these decisions and deal with the influence of the aircraft ground handling (turnaround) process, an important aspect of airport operations that is known to often create havoc in flight timetables. The analysis of the literature focuses on how to harness turnaround resilience to improve airline schedule robustness and applies a framework of variables (characteristics) to support data collection and synthesis. The variables include levels of integration of multiple planning stages, uncertainty modelling, turnaround consideration, type of robustness sought, and type of optimisation method employed. Based on our review, we propose a comprehensive airline scheduling process that incorporates turnaround planning to enhance the estimation of aircraft turn time, crew sit time, and passenger connecting time under uncertainty. More precise estimates will enable models to produce robust schedules at a lower cost (shorter buffer times). Since third-party organisations typically operate turnarounds, this planning approach needs to involve multiple autonomous decision-makers. Therefore, we encourage a collaborative robust scheduling framework to be built on existing operations research theories and industry protocols
Domestic dogs (Canis familiaris) recognise meaningful content in monotonous streams of read speech
No full textDomestic dogs (Canis familiaris) can recognize basic phonemic information from human speech and respond to commands. Commands are typically presented in isolation with exaggerated prosody known as dog-directed speech (DDS) register. Here, we investigate whether dogs can spontaneously identify meaningful phonemic content in a stream of putatively irrelevant speech spoken in monotonous prosody, without congruent prosodic cues. To test this ability, dogs were played recordings of their owners reading a meaningless text which included a short meaningful or meaningless phrase, either read with unchanged reading prosody or with an exaggerated DDS prosody. We measured the occurrence and duration of dogs’ gaze at their owners. We found that, while dogs were more likely to detect and respond to inclusions that contained meaningful phrases spoken with DDS prosody, they were still able to detect these meaningful inclusions spoken in a neutral reading prosody. Dogs detected and responded to meaningless control phrases in DDS as frequently as to meaningful content in neutral reading prosody, but less often than to meaningful content in DDS. This suggests that, while DDS prosody facilitates the detection of meaningful content in human speech by capturing dogs’ attention, dogs are nevertheless capable of spontaneously recognizing meaningful phonemic content within an unexaggerated stream of speech.</p
Experimental implementation of an actively controlled tuned vibration absorber using piezoelectric actuators
No full textTuned vibration absorbers (TVAs) are known to provide effective vibration control at their specific tuning frequency. They can effectively dissipate vibration energy from the host structure, making them useful for the control of both time invariant tonal excitation and structural resonances. However, they are ineffective away from their tuning frequency, making them unsuitable for applications where broadband vibration control is required or where there is significant variance in the system dynamics or the vibration spectrum. By incorporating some form of actuation and sensing into a TVA, active control can be used to vary the response of a TVA after production, tuning the TVA dynamics to the potential time varying application requirements. This paper explores the tunability of a specific TVA design, where the spring elements of the TVA are actuated using piezoelectric patch actuators. Previous work has studied thetheoretical limits of controlling the dynamics of this TVA design using feedback control strategies. The work presented in this paper extends this to an experimental implementation of active control on the proposed TVA design using commercially available piezoelectric actuators and sensors to establish thepractical limits on actively tuning the considered TVA design
The peculiar hard state behaviour of the black hole X-ray binary Swift J1727.8−1613
No full textTracking the correlation between radio and X-ray luminosities during black hole X-ray binary outbursts is a key diagnostic of the coupling between accretion inflows (traced by X-rays) and relativistic jet outflows (traced by radio). We present the radio–X-ray correlation of the black hole low-mass X-ray binary Swift J1727.8−1613 during its 2023–2024 outburst. Our observations span a broad dynamic range, covering ∼4 orders of magnitude in radio luminosity and ∼6.5 in X-ray luminosity. This source follows an unusually radio-quiet track, exhibiting significantly lower radio luminosities at a given X-ray luminosity than both the standard (radio-loud) track and most previously known radio-quiet systems. Across most of the considered distance range(D ∼ 1.5–4.3 kpc), Swift J1727.8−1613 appears to be the most radio-quiet black hole binary identified to date. For distances≥ 4 kpc, while Swift J1727 becomes comparable to one other extremely radio-quiet system, its peak X-ray luminosity (≥ 5×1038erg s−1) exceeds that of any previously reported hard-state black hole low-mass X-ray binary, emphasizing the extremity of this outburst. Additionally, for the first time in a radio-quiet system, we identify the onset of X-ray spectral softening to coincide with a change in trajectory through the radio–X-ray plane. We assess several proposed explanations for radio-quiet behaviour in black hole systems in light of this data set. As with other such sources, however, no single mechanism fully accounts for the observed properties, highlighting the importance of regular monitoring and the value of comprehensive (quasi-)simultaneous data-set
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