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Room reflections and constancy in speech-like sounds: within-band effects
The experiment asks whether constancy in hearing precedes or follows grouping. Listeners heard speech-like
sounds comprising 8 auditory-filter shaped noise-bands that had temporal envelopes corresponding to those
arising in these filters when a speech message is played. The „context‟ words in the message were “next you‟ll
get _to click on”, into which a “sir” or “stir” test word was inserted. These test words were from an 11-step
continuum that was formed by amplitude modulation. Listeners identified the test words appropriately and quite
consistently, even though they had the „robotic‟ quality typical of this type of 8-band speech. The speech-like
effects of these sounds appears to be a consequence of auditory grouping. Constancy was assessed by comparing
the influence of room reflections on the test word across conditions where the context had either the same level
of reflections, or where it had a much lower level. Constancy effects were obtained with these 8-band sounds,
but only in „matched‟ conditions, where the room reflections were in the same bands in both the context and the
test word. This was not the case in a comparison „mismatched‟ condition, and here, no constancy effects were
found. It would appear that this type of constancy in hearing precedes the across-channel grouping whose
effects are so apparent in these sounds. This result is discussed in terms of the ubiquity of grouping across
different levels of representation
Discharge amplified photo-emission from ultra-thin films applied to tuning work function of transparent electrodes in organic opto-electronic devices
A novel photoemission technique utilising localised discharge amplification of photo-yield is reported. It enables fast, accurate measurement of work function and ionisation potential for ultra-thin buffer layers vacuum deposited onto single and multilayer transparent conducting electrodes for organic solar cells and OLED's. Work function in most traditional transparent electrodes has to be raised to maximise charge transfer while high transmittance and high conductance must be retained. Results are presented for a range of metal oxide buffers, which achieve this goal. This compact photo-yield spectroscopy tool with its fast turn-around has been a valuable development aid since ionisation potential can vary significantly as deposition conditions change slightly, and as ultra-thin films grow. It has also been useful in tracking the impact of different post deposition cleaning treatments along with some storage and transport protocols, which can adversely reduce ionisation potential and hence subsequent device performance. © 2013 Elsevier B.V. All rights reserved
A low band gap co-polymer of dithienogermole and 2,1,3-benzothiadiazole by Suzuki polycondensation and its application in transistor and photovoltaic cells
Sustainability considerations for organic electronic products.
The development of organic electronic applications has reached a critical point. While markets, including the Internet of Things, transparent solar and flexible displays, gain momentum, organic light-emitting diode displays lead the way, with a current market size of over $25 billion, helping to create the infrastructure and ecosystem for other applications to follow. It is imperative to design built-in sustainability into the materials selection, processing and device architectures of all of these emerging applications, and to close the loop for a circular approach. In this Perspective, we evaluate the status of embedded carbon in organic electronics, as well as options for more sustainable materials and manufacturing, including engineered recycling solutions that can be applied within the product architecture and at the end of life. This emerging industry has a responsibility to ensure a 'cradle-to-cradle' approach. We highlight that ease of dismantling and recycling needs to closely relate to the product lifetime, and that regeneration should be facilitated in product design. Materials choices should consider the environmental effects of synthesis, processing and end-product recycling as well as performance
Active normal faults and coupled landscape response: bedrock variability in the southern Gulf of Corinth, central Greece
Fluvial erosion processes control landscape response to climatic and tectonic signals and its propagation into sedimentary basins. Considerable effort has gone into quantifying and modelling the effect of changes in uplift rates on fluvial erosion in bedrock rivers. However, current landscape models, based on stream power, tend to ignore the effects bedrock variability. The lack of available data relating rock strength to bedrock erodibility in fluvial settings has limited our ability to explore this question. Recent attempts at modelling to resolve this issue rely on indirect or theoretical rock strength properties. An alternative approach requires field measurements of rock strength together with geomorphological and tectonic constraints to quantify the effect of rock strength on river evolution. The Gulf of Corinth, central Greece, is one of the fastest extending rifts in the world and tectonic boundary conditions are well constrained. We (1) review published constraints on uplift along the active normal faults on the southern coast of the Gulf, and project uplift away from the faults into three catchments using a viscoelastic dislocation model; (2) test how channel width and slope vary in these rivers upstream of the active faults, and we use this data to estimate the distribution of stream power down-system; (3) systematically measure rock strength, using a Schmidt hammer, to constrain its effect on river response to uplift. All the rivers have knickpoints upstream of the active faults and we show they are responding transiently to active faulting. By assuming that our derived uplift rate equals stream power-driven erosion rate we calculate the erodibility, k, of bedrock. We demonstrate that stream powers in rivers crossing faults in the southern Gulf of Corinth correlate with rock strength and derive a non-linear power relationship between bedrock erodibility k and Schmidt hammer rebound. These findings highlight the need to incorporate bedrock variability into stream power erosion models
Do home modifications reduce care home admissions for older people? A matched control evaluation of the Care & Repair Cymru service in Wales
Background:
home advice and modification interventions aim to promote independent living for those living in the community, but quantitative evidence of their effectiveness is limited.
Aim:
assess the risk of care home admissions for people with different frailty levels receiving home advice and modification interventions against a control group who do not.
Study design and setting:
matched control evaluation using linked longitudinal data from the Secure Anonymised Information Linkage (SAIL) Databank, comprising people aged 60–95, registered with a SAIL contributing general practice. The intervention group received the Care & Repair Cymru (C & RC) service, a home advice and modification service available to residents in Wales.
Methods:
frailty, age and gender were used in propensity score matching to assess the Hazard Ratio (HR) of care home admissions within a 1-, 3- and 5-year period for the intervention group (N = 93,863) compared to a matched control group (N = 93,863). Kaplan–Meier curves were used to investigate time to a care home admission.
Results:
the intervention group had an increased risk of a care home admission at 1-, 3- and 5-years [HR (95%CI)] for those classified as fit [1-year: 2.02 (1.73, 2.36), 3-years: 1.87 (1.72, 2.04), 5-years: 1.99 (1.86, 2.13)] and mildly frail [1-year: 1.25 (1.09, 1.42), 3-years: 1.25 (1.17, 1.34), 5-years: 1.30 (1.23, 1.38)], but a reduced risk of care home admission for moderately [1-year: 0.66 (0.58, 0.75), 3-years: 0.75 (0.70, 0.80), 5-years: 0.83 (0.78, 0.88)] and severely frail individuals [1-year: 0.44 (0.37, 0.54), 3-years: 0.54 (0.49, 0.60), 5-years: 0.60(0.55, 0.66)].
Conclusions:
HRs indicated that the C & RC service helped to prevent care home admissions for moderately and severely frail individuals. The HRs generally increased with follow-up duration
New constraints on bedrock erodibility and landscape response times upstream of an active fault
A benzotrithiophene-based low band gap polymer for polymer solar cells with high open-circuit voltage
Synthesis of novel thieno[3,2-b]thienobis(silolothiophene) based low bandgap polymers for organic photovoltaics
Thieno[3,2-b]thienobis(silolothiophene), a new electron rich hexacyclic monomer has been synthesized and incorporated into three novel donor–acceptor low-bandgap polymers. By carefully choosing the acceptor co-monomer, the energy levels of the polymers could be modulated and high power conversion efficiencies of 5.52% were reached in OPV devices
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