645 research outputs found

    Scale-up of enface electrochemical reactor systems

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    Ph.DPhotolithography, the standard pattern transfer technique, has many sustainable issues due to the application of a mask to the substrate. A ‘maskless’ pattern transfer method, called the Enface technique, has recently been proposed for metal plating and etching. This method introduces the idea of bringing a patterned tool and a substrate together in close proximity and a current or voltage is passed between them enabling metal to be selectively deposited or removed from the substrate. The process requires sufficient electrolyte agitation within a narrow inter-electrode gap and has previously been shown to hold in a vertical flow channel reactor. However, the process has to be adapted for tank-type systems for industrial implementation. Mass transfer during electrodeposition can be enhanced by ultrasonic waves. It has therefore been investigated whether this would be an appropriate agitation method for Enface. In order to scale-up the process, 3 types of Enface reactors were investigated; a vertical flow cell, a 500 ml lab-scale tank-type cell and an 18 L ultrasound plating tank. The limiting current technique was used to study the mass transfer in these systems. Electrodeposition of copper pattern features in 0.1 M CuSO4 was achieved in each of these geometries. The scalability was quantified by measuring the uniformity of deposit roughness and deposit thickness of the features across the substrate using profilometry. The lab-scale tank-type cell with a 20 kHz ultrasound probe was used to investigate the effect of ultrasound agitation within narrow inter-electrode gaps. Mass transfer correlations showed that turbulent flow becomes fully developed when using ultrasound in this narrow geometry. Limiting current experiments showed that relatively low ultrasound powers of 9 – 18 W/cm2 should be used and current distribution modelling showed that the ultrasound source should be placed no less than 30 mm from the substrate. Copper pattern features were deposited onto 10 mm diameter substrates and using long current pulses with bursts of ultrasound during the off-time was the most suitable plating mode. Specially designed electrode holders in the large-scale 18 L ultrasound tank was used to deposit copper patterns onto larger substrates. Features of ÎŒm-scale were deposited onto A7 size substrates, but there was an unacceptable variation in deposit thickness of ±80% due to the non-uniformity of the electrode gap across the plate. However, mm-scale features were successfully deposited onto A7 size substrates with an acceptable deposit thickness uniformity and deposit roughness uniformity of ±18% and ±40% respectively across the plate. Enface is therefore currently scalable for mm-scale features on substrates of this size.EPSRC, E

    Plasticity in nest site choice behavior in response to hydric conditions in a reptile

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    Natural selection is expected to select for and maintain maternal behaviors associated with choosing a nest site that promotes successful hatching of offspring, especially in animals that do not exhibit parental care such as reptiles. In contrast to temperature effects, we know little about how soil moisture contributes to successful hatching and particularly how it shapes nest site choice behavior in nature. The recent revelation of exceptionally deep nesting in lizards under extreme dry conditions underscored the potential for the hydric environment in shaping the evolution of nest site choice. But if deep nesting is an adaptation to dry conditions, is there a plastic component such that mothers would excavate deeper nests in drier years? We tested this hypothesis by excavating communal warrens of a large, deep-nesting monitor lizard (Varanus panoptes), taking advantage of four wet seasons with contrasting rainfall amounts. We found 75 nests during two excavations, including 45 nests after a 4-year period with larger wet season rainfall and 30 nests after a 4-year period with smaller wet season rainfall. Mothers nested significantly deeper in years associated with drier nesting seasons, a finding best explained as a plastic response to soil moisture, because differences in both the mean and variance in soil temperatures between 1 and 4 m deep are negligible. Our data are novel for reptiles in demonstrating plasticity in maternal behavior in response to hydric conditions during the time of nesting. The absence of evidence for other ground-nesting reptile mothers adjusting nest depth in response to a hydric-depth gradient is likely due to the tradeoff between moisture and temperature with changing depth; most ground-nesting reptile eggs are deposited at depths of ~ 2–25 cm—nesting deeper within or outside of that range of depths to achieve higher soil moisture would also generally create cooler conditions for embryos that need adequate heat for successful development. In contrast, extreme deep nesting in V. panoptes allowed us to disentangle temperature and moisture. Broadly, our data suggest that ground-nesting reptiles can assess soil moisture and respond by adjusting the depth of the nest, but may not, due to the cooling effect of nesting deeper. Our results, within the context of previous work, provide a more complete picture of how mothers can promote hatching success through adjustments in nest site choice behavior

    Survey Evidence on Conditional Norm Enforcement

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    We discuss survey evidence on individuals' willingness to sanction norm violations - such as evading taxes, drunk driving, fare dodging, or skiving o work - by expressing disapproval or social exclusion. Our data suggest that people condition their sanctioning behavior on their belief about the frequency of norm violations. The more commonly a norm violation is believed to occur, the lower the individuals' inclination to punish it. Based on an instrumental variable approach, we demonstrate that this pattern reflects a causal relationship

    General dimensions of human brain morphometry inferred from genome-wide association data

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    Understanding the neurodegenerative mechanisms underlying cognitive decline in the general population may facilitate early detection of adverse health outcomes in late life. This study investigates genetic links between brain morphometry, ageing and cognitive ability. We develop Genomic Principal Components Analysis (Genomic PCA) to model general dimensions of brain-wide morphometry at the level of their underlying genetic architecture. Genomic PCA is applied to genome-wide association data for 83 brain-wide volumes (36,778 UK Biobank participants) and we extract genomic principal components (PCs) to capture global dimensions of genetic covariance across brain regions (unlike ancestral PCs that index genetic similarity between participants). Using linkage disequilibrium score regression, we estimate genetic overlap between those general brain dimensions and cognitive ageing. The first genetic PCs underlying the morphometric organisation of 83 brain-wide regions accounted for substantial genetic variance (R2  = 40%) with the pattern of component loadings corresponding closely to those obtained from phenotypic analyses. Genetically more central regions to overall brain structure - specifically frontal and parietal volumes thought to be part of the central executive network - tended to be somewhat more susceptible towards age (r = -0.27). We demonstrate the moderate genetic overlap between the first PC underlying each of several structural brain networks and general cognitive ability (rg  = 0.17-0.21), which was not specific to a particular subset of the canonical networks examined. We provide a multivariate framework integrating covariance across multiple brain regions and the genome, revealing moderate shared genetic etiology between brain-wide morphometry and cognitive ageing

    SATRE: Standardised Architecture for Trusted Research Environments

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    The SATRE DARE UK-funded Driver Project was challenged to create a trusted research environment (TRE) architecture supporting the research community's need to have suitable data analytics and research environments for working with sensitive data. The project developed an inclusive and transparent way of working to ensure that what was created was representative of the TRE community in the UK. We have created, for the first time, an open specification for TRE operators by which to evaluate themselves against a set of capabilities. It is a thorough specification, perhaps definition, for TREs informed not only by the experience of the project team who have been running a TRE and supporting sensitive data projects for a combined 15 years but also the expansive knowledge of the wider UK research community. The public has also been involved throughout the development of the specification to ensure their voices are heard and reflected in the specification. The specification has been informed through one survey completed by 105 individuals representing approximately 60 organisations, 14 Collaboration Cafés with up to 75 participants, 26 individuals contributing directly, 44 issues raised and six public engagement sessions online and in-person. Despite the breadth and diversity of the individuals included, we have been able to create a single specification encompassing four architectural principles, four pillars, 29 capabilities and 160 statements. The 75 mandatory statements are what is considered the minimum required to be a SATRE-compliant TRE. Now, with a stable version 1.0 release, the specification is ready for use by the UK TRE community. We are and will continue to work with all organisations to evaluate themselves against the specification and also identify what works and what doesn't, which will be captured in future versions of the specification. The specification has been developed with the long-term in mind and can be a basis for a common understanding between operators, data controllers, accreditors, researchers, industry and government organisations for how TREs can federate and interoperate better.This work was funded by UK Research & Innovation [Grant Number MC_PC_23008] as part of Phase 1 of the DARE UK (Data and Analytics Research Environments UK) programme, delivered in partnership with Health Data Research UK (HDR UK) and Administrative Data Research UK (ADR UK)

    Re-examining the effects of verbal instructional type on early stage motor learning

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    The present study investigated the differential effects of analogy and explicit instructions on early stage motor learning and movement in a modified high jump task. Participants were randomly assigned to one of three experimental conditions: analogy, explicit light (reduced informational load), or traditional explicit (large informational load). During the two-day learning phase, participants learned a novel high jump technique based on the ‘scissors’ style using the instructions for their respective conditions. For the single-day testing phase, participants completed both a retention test and task-relevant pressure test, the latter of which featured a rising high-jump-bar pressure manipulation. Although analogy learners demonstrated slightly more efficient technique and reported fewer technical rules on average, the differences between the conditions were not statistically significant. There were, however, significant differences in joint variability with respect to instructional type, as variability was lowest for the analogy condition during both the learning and testing phases, and as a function of block, as joint variability decreased for all conditions during the learning phase. Findings suggest that reducing the informational volume of explicit instructions may mitigate the deleterious effects on performance previously associated with explicit learning in the literature

    Infall Times for Milky Way Satellites From Their Present-Day Kinematics

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    We analyze subhalos in the Via Lactea II (VL2) cosmological simulation to look for correlations among their infall times and z = 0 dynamical properties. We find that the present day orbital energy is tightly correlated with the time at which subhalos last crossed into the virial radius. This energy-infall correlation provides a means to infer infall times for Milky Way satellite galaxies. Assuming that the Milky Way's assembly can be modeled by VL2, we show that the infall times of some satellites are well constrained given only their Galactocentric positions and line-of-sight velocities. The constraints sharpen for satellites with proper motion measurements. We find that Carina, Ursa Minor, and Sculptor were all accreted early, more than 8 Gyr ago. Five other dwarfs, including Sextans and Segue 1, are also probable early accreters, though with larger uncertainties. On the other extreme, Leo T is just falling into the Milky Way for the first time while Leo I fell in \sim 2 Gyr ago and is now climbing out of the Milky Way's potential after its first perigalacticon. The energies of several other dwarfs, including Fornax and Hercules, point to intermediate infall times, 2 - 8 Gyr ago. We compare our infall time estimates to published star formation histories and find hints of a dichotomy between ultrafaint and classical dwarfs. The classical dwarfs appear to have quenched star formation after infall but the ultrafaint dwarfs tend to be quenched long before infall, at least for the cases in which our uncertainties allow us to discern differences. Our analysis suggests that the Large Magellanic Cloud crossed inside the Milky Way virial radius recently, within the last \sim 4 billion years.Comment: 15 pages, 7 figures, all figures include colors, submitted for publication in MNRA

    Adjunctive Medication Management and Contingency Management to enhance adherence to acamprosate for alcohol dependence: the ADAM trial RCT

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    BackgroundAcamprosate is an effective and cost-effective medication for alcohol relapse prevention but poor adherence can limit its full benefit. Effective interventions to support adherence to acamprosate are therefore needed.ObjectivesTo determine the effectiveness of Medication Management, with and without Contingency Management, compared to Standard Support alone in enhancing adherence to acamprosate and the impact of adherence to acamprosate on abstinence and reduced alcohol consumption.DesignMulticentre, three-arm, parallel-group, randomised controlled clinical trial.SettingSpecialist alcohol treatment services in five regions of England (South East London, Central and North West London, Wessex, Yorkshire and Humber and West Midlands).ParticipantsAdults (aged 18 years or more), an International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, diagnosis of alcohol dependence, abstinent from alcohol at baseline assessment, in receipt of a prescription for acamprosate.Interventions(1) Standard Support, (2) Standard Support with adjunctive Medication Management provided by pharmacists via a clinical contact centre (12 sessions over 6 months), (3) Standard Support with adjunctive Medication Management plus Contingency Management that consisted of vouchers (up to £120) to reinforce participation in Medication Management. Consenting participants were randomised in a 2 : 1 : 1 ratio to one of the three groups using a stratified random permuted block method using a remote system. Participants and researchers were not blind to treatment allocation.Main outcome measuresPrimary outcome: self-reported percentage of medication taken in the previous 28 days at 6 months post randomisation. Economic outcome: EuroQol-5 Dimensions, a five-level version, used to calculate quality-adjusted life-years, with costs estimated using the Adult Service Use Schedule.ResultsOf the 1459 potential participants approached, 1019 (70%) were assessed and 739 (73 consented to participate in the study, 372 (50%) were allocated to Standard Support, 182 (25%) to Standard Support with Medication Management and 185 (25%) to Standard Support and Medication Management with Contingency Management. Data were available for 518 (70%) of participants at 6-month follow-up, 255 (68.5%) allocated to Standard Support, 122 (67.0%) to Standard Support and Medication Management and 141 (76.2%) to Standard Support and Medication Management with Contingency Management. The mean difference of per cent adherence to acamprosate was higher for those who received Standard Support and Medication Management with Contingency Management (10.6%, 95% confidence interval 19.6% to 1.6%) compared to Standard Support alone, at the primary end point (6-month follow-up). There was no significant difference in per cent days adherent when comparing Standard Support and Medication Management with Standard Support alone 3.1% (95% confidence interval 12.8% to −6.5%) or comparing Standard Support and Medication Management with Standard Support and Medication Management with Contingency Management 7.9% (95% confidence interval 18.7% to −2.8%). The primary economic analysis at 6 months found that Standard Support and Medication Management with Contingency Management was cost-effective compared to Standard Support alone, achieving small gains in quality-adjusted life-years at a lower cost per participant. Cost-effectiveness was not observed for adjunctive Medication Management compared to Standard Support alone. There were no serious adverse events related to the trial interventions reported.LimitationsThe trial’s primary outcome measure changed substantially due to data collection difficulties and therefore relied on a measure of self-reported adherence. A lower than anticipated follow-up rate at 12 months may have lowered the statistical power to detect differences in the secondary analyses, although the primary analysis was not impacted.ConclusionsMedication Management enhanced with Contingency Management is beneficial to patients for supporting them to take acamprosate
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