The asymptotics of the moving contact line: cracking an old nut

This article has been published in a revised form in Journal of Fluid Mechanics https://doi.org/10.1017/jfm.2014.702. This version is free to view and download for private research and study only. Not for re-distribution, re-sale or use in derivative works. © Cambridge University Press.For contact line motion where the full Stokes flow equations hold, full matched asymptotic solutions using slip models have been obtained for droplet spreading and more general geometries. These solutions to the singular perturbation problem in the slip length, however, all involve matching through an intermediate region that is taken to be separate from the outer-inner regions. Here, we show that the intermediate region is in fact an overlap region representing extensions of both the outer and the inner region, allowing direct matching to proceed. In particular, we investigate in detail how a previously seen result of the matching of the cubes of the free surface slope is justified in the lubrication setting. We also extend this two-region direct matching to the more general Stokes flow case, offering a new perspective on the asymptotics of the moving contact line problem

The Effects of Long-Term Muscle Disuse on Neuromuscular Function in Unilateral Transtibial Amputees

The purpose of this study was to determine: (1) whether individuals with unilateral transtibial amputations (ITTAs), who habitually disuse the quadriceps muscles of their amputated limb, provide an effective model for assessing the effects of long-term muscle disuse; and (2) the effects of such disuse on quadriceps muscle strength and neuromuscular function in this population. Nine ITTAs and nine controls performed isometric voluntary knee extensions in both limbs to assess maximal voluntary torque (MVT) and rate of torque development (RTD). The interpolated twitch technique and EMG normalised to maximal M-wave assessed neural activation, involuntary (twitch and octet) contractions assessed intrinsic contractile properties, and ultrasound images of the vastus lateralis assessed muscle architecture. Clinical gait analysis was used to measure knee kinetic data during walking at an habitual speed. ITTAs displayed 54-60% lower peak knee extensor moments during walking in the amputated than intact/control limbs, but the intact and control limbs were comparable for loading during walking and muscle strength variables, suggesting the intact limb provides a suitable internal control for comparison to the disused amputated limb. MVT and RTD were ~60% and ~75% lower, respectively, in the amputated than intact/control limbs. The differences in MVT appeared associated with ~40% and ~43% lower muscle thickness and neural activation, respectively, whilst the differences in RTD appeared associated with the decline in MVT coupled with slowing of the intrinsic contractile properties. These results indicate considerable changes in strength and neuromuscular function with long-term disuse, that could not be predicted from short-term disuse studies. This is the peer reviewed version of the following article: The Effects of Long-Term Muscle Disuse on Neuromuscular Function in Unilateral Transtibial Amputees, which has been published in final form at Experimental Physiology. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Version

Cooperative phenotype predicts climate change belief and pro-environmental behaviour

Understanding the psychological causes of variation in climate change belief and pro-environmental behaviour remains an urgent challenge for the social sciences. The “cooperative phenotype” is a stable psychological preference for cooperating in social dilemmas that involve a tension between individual and collective interest. Since climate change poses a social dilemma on a global scale, this issue may evoke similar psychological processes as smaller social dilemmas. Here, we investigate the relationships between the cooperative phenotype and climate change belief and behaviour with a representative sample of New Zealanders (n = 897). By linking behaviour in a suite of economic games to self-reported climate attitudes, we show robust positive associations between the cooperative phenotype and both climate change belief and pro-environmental behaviour. Furthermore, our mediation analyses support a motivated reasoning model in which the relationship between the cooperative phenotype and pro-environmental behaviour is fully mediated by climate change belief. These findings suggest that common psychological mechanisms underlie cooperation in both micro-scale social dilemmas and larger-scale social dilemmas like climate change.Results and discussions Methods - Power analysis - Participants and sampling - Materials - Procedure - Statistical analyse

Fluid structure in the immediate vicinity of an equilibrium three-phase contact line and assessment of disjoining pressure models using density functional theory

We examine the nanoscale behavior of an equilibrium three-phase contact line in the presence of long-ranged intermolecular forces by employing a statistical mechanics of fluids approach, namely density functional theory (DFT) together with fundamental measure theory (FMT). This enables us to evaluate the predictive quality of effective Hamiltonian models in the vicinity of the contact line. In particular, we compare the results for mean field effective Hamiltonians with disjoining pressures defined through (I) the adsorption isotherm for a planar liquid film, and (II) the normal force balance at the contact line. We find that the height profile obtained using (I) shows good agreement with the adsorption film thickness of the DFT-FMT equilibrium density profile in terms of maximal curvature and the behavior at large film heights. In contrast, we observe that while the height profile obtained by using (II) satisfies basic sum rules, it shows little agreement with the adsorption film thickness of the DFT results. The results are verified for contact angles of 20, 40 and 60 degrees

First light for avian embryos: eggshell thickness and pigmentation mediate variation in development and UV exposure in wild bird eggs

Article first published online: 29 JUL 20141. The avian embryo's development is influenced by both the amount and the wavelength of the light that passes through the eggshell. Commercial poultry breeders use light of specific wavelengths to accelerate embryonic growth, yet the effects of the variably patterned eggshells of wild bird species on light transmission and embryonic development remain largely unexplored. 2. Here, we provide the first comparative phylogenetic analysis of light transmission, through a diverse range of bird eggshells (74 British breeding species), in relation to the eggshell's thickness, permeability, pigment concentration and surface reflectance spectrum (colour). 3. The percentage of light transmitted through the eggshell was measured in the spectral range 250–700 nm. Our quantitative analyses confirm anecdotal reports that eggshells filter the light of the externally coloured shell. Specifically, we detected a positive relationship between surface eggshell reflectance (‘brightness’) and the percentage of light transmitted through the eggshell, and this relationship was strongest at wavelengths in the human-visible blue-green region of the spectra (c. 435 nm). 4. We show that less light passes through thicker eggshells with greater total pigment concentrations. By contrast, permeability (measured as water vapour conductance) did not covary significantly with light transmission. Eggs of closed-nesting species let more light pass through, compared with open nesters. 5. We postulate that greater light transmission is required to assist embryonic development under low light exposure. Importantly, this result provides an ecological explanation for the repeated evolution of immaculate, white- or pale-coloured eggshells in species nesting in enclosed spaces. 6. Finally, we detected correlative support for the solar radiation hypothesis, in that eggshells of bird species with a longer incubation period let significantly less of the potentially harmful, ultraviolet (UV) light pass through the eggshell. In summary, we demonstrate suites of avian eggshell properties, including eggshell structure and pigmentation, which are consistent with an evolutionary pressure to both enhance and protect embryonic development.Golo Maurer, Steven J. Portugal, Mark E. Hauber, Ivan Mikšík, Douglas G. D. Russell and Phillip Casse

Identifying core strategies and mechanisms for spreading a national medicines optimisation programme across England-a mixed-method study applying qualitative thematic analysis and Qualitative Comparative Analysis

BACKGROUND: Achieving widespread adoption of innovations across health systems remains a challenge. Past efforts have focused on identifying and classifying strategies to actively support innovation spread (replicating an innovation across sites), but we lack an understanding about the mechanisms which such strategies draw on to deliver successful spread outcomes. There is also no established methodology to identify core strategies or mechanisms which could be replicated with fidelity in new contexts when spreading innovations. We aimed to understand which strategies and mechanisms are connected with successful spread using the case of a national medicines optimisation programme in England. METHODS: The study applied a comparative mixed-method case study approach. We compared spread activity in 15 Academic Health Science Networks (AHSN) in England, applied to one innovation case, Transfers of Care Around Medicines (TCAM). We followed two methodological steps: (1) qualitative thematic analysis of primary data collected from 18 interviews with AHSN staff members to identify the strategies and mechanisms and related contextual determinants and (2) Qualitative Comparative Analysis (QCA) combining secondary quantitative data on spread outcome and qualitative themes from step 1 to identify the core strategies and mechanisms. RESULTS: We identified six common spread strategy-mechanism constructs that AHSNs applied to spread the TCAM national spread programme: (1) the unique intermediary position of the AHSN as "honest broker" and local networking organisation, (2) the right capacity and position of the spread facilitator, (3) an intersectoral and integrated stakeholder engagement approach, (4) the dynamic marriage of the innovation with local health and care system needs and characteristics, (5) the generation of local evidence, and (6) the timing of TCAM. The QCA resulted in the core strategy/mechanism of a timely start into the national spread programme in combination with the employment of a local, senior pharmacist as an AHSN spread facilitator. CONCLUSIONS: By qualitatively comparing experiences of spreading one innovation across different contexts, we identified common strategies, causal mechanisms, and contextual determinants. The QCA identified one core combination of two strategies/mechanisms. The identification of core strategies/mechanisms and common pre-conditional and mediating contextual determinants of a specific innovation offers spread facilitators and implementers a priority list for tailoring spread activities

Identification of \u3ci\u3eBrucella\u3c/i\u3e spp. in feral swine (\u3ci\u3eSus scrofa\u3c/i\u3e) at abattoirs in Texas, USA

Various tissues, nasal swabs, urine and blood samples were collected from 376 feral swine at two federally inspected abattoirs in Texas during six separate sampling periods in 2015. Samples were tested for Brucella spp. by culture and serology. Brucella spp. were cultured from 13.0% of feral swine, and antibodies were detected in 9.8%. Only 32.7% of culture-positive feral swine were also antibody positive, and 43.2% of antibody-positive feral swine were culture positive. Approximately, the same number of males (14.0%) and females (12.1%) were culture positive, and slightly more males (10.5%) than females (8.7%) were antibody positive. Our results indicate that serology likely underestimates the prevalence of feral swine infected, and that those who come in contact with feral swine should be aware of the symptoms of infection with Brucella spp. to ensure prompt treatment

Renal and hypotensive effects of acute and chronic oral treatment with 1-hydrazinophthalazine (apresoline) in hypertension

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32532/1/0000634.pd