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Separating the causes of listening difficulties in children
No full textAuditory processing disorder (APD), defined here as a deficit in the way sounds are analysed by the brain, has remained a controversial topic within audiology for decades. Some of the controversy concerns what it is called. More substantively, even its existence has been questioned. That view has likely emerged because there has not been sufficient rigor in determining when difficulty in understanding speech has been the consequence of some type of auditory processing deficit, versus when it is the consequence of a cognitive deficit or a language deficit. This paper suggests that the field use the term “listening difficulty” as an umbrella term to indicate a reported deficit in recognising sounds or understanding speech, one possible cause of which is an APD. Other possible causes are hearing deficits, cognitive deficits, and language deficits. This paper uses a plausible, and hopefully non-controversial, model of speech understanding that comprises auditory processing, speech processing, and language processing, all potentially affected by the degree of attention applied and the listener’s memory ability. In a fresh approach to the construction of test batteries, the stages of the model are linked to tests designed to assess either all or selected parts of the processes involved. For two of the stages, a listener’s performance is quantified as the additional signal-to-noise ratio that he or she needs to function equivalently to his or her age peers. Subtraction of the deficits revealed by each test enables the contributions of each processing stage to a listening deficit to be quantified. As a further novel contribution, the impact of memory and attention on each test score is quantitatively allowed for, by an amount that depends on each test’s dependence on memory and attention. Attention displayed during the test is estimated from the fluctuations in performance during the test.The paper concludes with a summary of the research that must be conducted before the structured tests can be used to quantify the extent to which different potential causes of listening difficulties are responsible for real-life difficulties in an individual child.<br/
Assessing the Superhydrophobic Performance of Laser Micropatterned Aluminium Overhead Line Conductor Material
No full textOverhead electric supply lines are subject to water and ice accumulation, causing noise and weight increase, and leading to faults or failures. In this research, micro-textures were laser-ablated on aluminium substrates representative of overhead line conductors to achieve superhydrophobic properties. Samples were then subjected to a range of tests to measure the resilience and durability of such surfaces to conditions experienced byoverhead line conductors. Tests to examine thermal ageing, thermal cycling, UV exposure, long term ambient outdoor environment exposure, and corona exposure testing were conducted and the evolution of surface superhydrophobicity was quantified. A high degree of resilience was observed for most of the testing. The feasibility of manufacturing upscale is discussed in addition to optimising test methods
Differential Weil Descent
No full textIn this short note a differential version of the classical Weil descent is established in all characteristics. This yields a ready-to-deploy tool of differential restriction of scalars for differential varieties over finite differential field extensions
Impact of shift working on the potential for self-powering via kinetic energy harvesting in wearable devices
No full textWearable devices are having a transformative impact on personalised monitoring and care. However, they frequently have limited battery life, requiring charging every few days; a major source of user frustration. Kinetic energy harvesting may help overcome this, collecting energy from the user’s motion to allow the device to self-charge. While there are many works which have investigated wearable energy harvesting potential, none have incorporated socio-economic factors which affect activity, such as occupation type, on energy harvesting potential. We use the UK Biobank free-living accelerometer dataset to investigate the impact of occupational patterns on energy harvesting potential for the first time. We identify that those following shift patterns have a different distribution of when power is available, with those who work shifts having the most power intense period spread over a longer period of the day compared to controls. When stratifying into day or night shift work, we identify that those who work night shifts have a large variation between participants, as their most energy dense period is spread over the entire 24-hour period. This is compared to day shift workers who have the most power concentrated within a substantially smaller window, typically in the morning. Considering these socio-economic factors may affect system design of wearable energy harvesters
Full Slonczewski-Weiss-McClure parametrization of few-layer twistronic graphene
No full textWe use a hybrid k p theory - tight binding (HkpTB) model to describe interlayer coupling simultaneously in both Bernal and twisted graphene structures. For Bernal-aligned interfaces, HkpTB is parametrized using the full Slonczewski-Weiss-McClure (SWMcC) Hamiltonian of graphite1, which is then used to refine the commonly used Bistritzer-MacDonald (BM) model for twisted interfaces2,3, by deriving additional terms that reflect all details of the full SWMcC model of graphite. We find that these terms introduce electron-hole asymmetry in the band structure of twisted bilayers, but in twistronic multilayer graphene, they produce only a subtle change of moir´e miniband spectra, confirming the broad applicability of the BM model for implementing the twisted interface coupling in such systems
Measurements of the diffuse Galactic synchrotron spectral index and curvature from MeerKLASS pilot data
No full text21cm intensity mapping experiments are bringing an influx of high spectral resolution observational data in the ∼ 100 MHz – 1 GHz regime. We use pilot 971 − 1075 MHz data from MeerKAT in single-dish mode, recently used to test the calibration and data reduction scheme of the upcoming MeerKLASS survey, to probe the spectral index of diffuse synchrotron emission below 1 GHz within 145◦ < 𝛼 < 180◦, −1◦ < 𝛿 < 8◦. Through comparisons with datafrom the OVRO Long Wavelength Array and the Maipu and MU surveys, we find an average spectral index of −2.75 < 𝛽 < −2.71 between 45 and 1055 MHz. By fitting for spectral curvature with a spectral index of the form 𝛽 + 𝑐 ln(𝜈/73 MHz), we measure 𝛽 = −2.55±0.13 and 𝑐 = −0.12 ± 0.05 within our target field. Our results are in good agreement (within 1𝜎) with existing measurements from experiments such as ARCADE2 and EDGES. These results show the calibration accuracy of current data and demonstrate that MeerKLASS will also be capable of achieving a secondary science goal of probing the interstellar medium
‘Very small effects of an imagery-based randomized trial to promote adherence to wearing face coverings during the COVID-19 pandemic and identification of future intervention targets’
No full textObjective: Mental imagery interventions are a cost-effective way of promoting health behaviour change. We tested a mental imagery intervention designed to promote adherence to wearing face coverings during the COVID-19 pandemic. Design: A four-arm randomized controlled trial to explore potential mechanisms of action. Main outcome measures: Measures of behaviour (frequency of self-reported face covering adherence), theory of planned behaviour constructs (i.e., intention, attitudes, subjective norms, and perceived behavioural control), personality traits, imagery ability and barrier self-efficacy were measured at baseline (T1). Behaviour was also assessed at four-week follow up (T2). Results: Of 297 participants, a majority always wore face coverings (N = 216, 73% overall sample). Logistic regression analyses revealed no intervention effects on changes in adherence to wearing face coverings, though T1 wearing of face coverings and being male predicted T2 behaviour. Subgroup analysis of participants with ‘suboptimal T1 adherence’, revealed that T2 non-adherence was predicted by being a non-student and by subjective norms and less intention to wear face coverings. Conclusion: Imagery-based interventions to increase face covering wearing adherence may exert significant public health effects but only when conducted on a very large scale. Our findings suggest that interventions should target men and disrupt habitual past behaviour. Key words: mental imagery intervention; behaviour change; COVID-19; face coverings; habitual past behaviour<br/
Venous cerebral blood flow quantification and cognition in patients with sickle cell anemia
No full textPrior studies have described high venous signal qualitatively using arterial spin labelling (ASL) in patients with sickle cell anemia (SCA), consistent with arteriovenous shunting. We aimed to quantify the effect and explored cross-sectional associations with arterial oxygen content (CaO2), disease-modifying treatments, silent cerebral infarction (SCI), and cognitive performance. 94 patients with SCA and 42 controls underwent cognitive assessment and MRI with single- and multi- inflow time (TI) ASL sequences. Cerebral blood flow (CBF) and bolus arrival time (BAT) were examined across gray and white matter and high-signal regions of the sagittal sinus. Across gray and white matter, increases in CBF and reductions in BAT were observed in association with reduced CaO2 in patients, irrespective of sequence. Across highsignal sagittal sinus regions, CBF was also increased in association with reduced CaO2 using both sequences. However, BAT was increased rather than reduced in patients across these regions, with no association with CaO2. Using the multiTI sequence in patients, increases in CBF across white matter and high-signal sagittal sinus regions were associated with poorer cognitive performance. These novel findings highlight the utility of multiTI ASL in illuminating, and identifying objectively quantifiable and functionally significant markers of, regional hemodynamic stress in patients with SCA.Keywords: Cerebrovascular disease, Hematology, Hemodynamics, Cognition, MRI Venous CBF quantification in sickle cell anemi
Working collaboratively to create a legacy: the development of The Critical Incident Resource
No full textCritical incidents (CIs) are sudden, unexpected events that have a significant impact upon children and young people. In response to the Manchester Arena bombing in May 2017, the association of regional educational psychology services (EPSs) created face-to-face training materials to support schools with CI response. In order to embed the legacy of this cross-service training initiative, the aim of this research was then to explore how these materials could be developed into an online resource through a process of action research. Supported by an IT expert, one trainee educational psychologist (TEP) and five EPs from different EPSs across the region formed a ‘task-and-finish’ group and followed a seven-phase process, including a pre- and post-phase. ‘The Critical Incident Resource’ (TCIR) website was created, to support EPs in their support for school CI response. The online resource development highlighted key project management skills for EPs including conceptual, human, negotiation and technical abilities
Oxidative dehalogenation of halophenols by high-valent nonheme iron(IV)-oxo intermediates
No full textMononuclear high-valent iron(IV)-oxo intermediates are excellent oxidants towards oxygenation reactions by heme and nonheme metalloenzymes and their model systems. One of the most important functions of these intermediates in nature is to detoxify various environmental pollutants. Organic substrates such as halogenated phenols are known to be water pollutants which can be degraded to their less hazardous forms through an oxidation reaction by iron(IV)-oxo complexes. Metalloproteins in the Nature utilize various types of second-coordination sphere interactions to anchor the substrate in the vicinity of the active site. This concept of substrate-binding is well-known for natural enzymes, but quite elusive for the relevant biomimetic model systems. Herein, we report the oxidative reactivity patterns of an iron(IV)-oxo intermediate, [FeIV(O)(2PyN2Q)]2+, (2PyN2Q = 1,1-di(pyridin-2yl)-N, N-bis(quinolin-2-ylmethyl)methanamine) with a series of mono-, diand tri-halophenols. A detailed experimental study shows that the dehalogenation reactions of the halophenols by such iron(IV)-oxo intermediates proceed via an initial hydrogen atom abstraction from the phenolic O-H group. Further, based on the size and nucleophilicity of the halophenol, an intermediate substrate-bound species forms , that is a phenolate adduct to the ferric species - which thereafter leads to the formation of the corresponding products.<br/