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Imbibition dynamics of nano-particulate ink-jet drops on micro-porous media
Ink-jet printing of nano-metallic colloidal fluids on to
porous media such as coated papers has become a viable
method to produce conductive tracks for low-cost,
disposable printed electronic devices. However, the
formation of well-defined and functional tracks on an
absorbing surface is controlled by the drop imbibition
dynamics in addition to the well-studied post-impact drop
spreading behavior.
This study represents the first investigation of the realtime
imbibition of ink-jet deposited nano-Cu colloid drops
on to coated paper substrates. In addition, the same ink was
deposited on to a non-porous polymer surface as a control
substrate. By using high-speed video imaging to capture the
deposition of ink-jet drops, the time-scales of drop
spreading and imbibition were quantified and compared
with model predictions. The influences of the coating pore
size on the bulk absorption rate and nano-Cu particle
distribution have also been studied
Ecological IVIS design : using EID to develop a novel in-vehicle information system
New in-vehicle information systems (IVIS) are emerging which purport to encourage more environment friendly or ‘green’ driving. Meanwhile, wider concerns about road safety and in-car distractions remain. The ‘Foot-LITE’ project is an effort to balance these issues, aimed at achieving safer and greener driving through real-time driving information, presented via an in-vehicle interface which facilitates the desired behaviours while avoiding negative consequences. One way of achieving this is to use ecological interface design (EID) techniques. This article presents part of the formative human-centred design process for developing the in-car display through a series of rapid prototyping studies comparing EID against conventional interface design principles. We focus primarily on the visual display, although some development of an ecological auditory display is also presented. The results of feedback from potential users as well as subject matter experts are discussed with respect to implications for future interface design in this field
The impact of experimental impact pile driving on oxygen uptake in black seabream and plaice
This is the final version of the article. Available from Acoustical Society of America via the DOI in this record.Fourth International Conference on the Effects of Noise on Aquatic Life, Dublin, Ireland, 10-16 July 2016Anthropogenic noise is a recognized global pollutant that could potentially impact many organisms, including fishes. One of the acoustic sources producing high impulsive noise and vibration is pile driving. However, the potential impacts of real pile driving on fish species has received little attention, mainly due to the logistical challenges involved. Here, we investigated the impact of pile driving on the oxygen uptake (a secondary stress response) of black seabream Spondyliosoma cantharus and European plaice Pleuronectes platessa using an experimental pile driver setup in a flooded ship-building dock. Each individual fish was tested in ambient and pile driving conditions using a counterbalanced paired design to control for potential order effects. During pile driving, black seabream increased oxygen uptake compared to the ambient control condition suggesting higher stress levels. Plaice did not show differences in oxygen consumption between the pile driving and ambient treatment. These results show the impact of pile driving on secondary stress responses in fish, highlight species-specific differences concerning acoustical impacts, and showcase the possibility of carrying out large-scale semi-field acoustic experiments.Thanks also to E.ON, NERC MREKE and Marine Scotland for financial support
A tool to predict the impact of anthropogenic noise on fish
Anthropogenic (man-made) noise is a global problem in aquatic and terrestrial environments. In the shallow seas around many countries, including the UK, large windfarms are being constructed using pile driving to create a solid base for the turbines. Offshore pile driving creates pulsating noises and vibrations of very high intensities, which has been shown to be deleterious to a variety of aquatic species. Using a hydrodynamic model that predicts the propagation of underwater noise while taking into account bathymetry, tidal movements and currents,
we integrated a numerical behavioural tool that models fish behaviour in response to noise. Using agent based modelling, scientifically published data and parameters obtained from carefully controlled experiments, we modelled the impact of noise on European sea bass (Dicentrarchus labrax) as they encountered pile driving during migration from the ocean to a spawning site close to the shore. Taking
our empirical experiments into account - which showed a negative impact of noise on feeding behaviour and increased oxygen consumption - the model predicts that the fish took significantly longer to arrive at the spawning site. This effect could have important implications at
a population level, as fish would use more energy to reach the site and might desynchronize spawning behaviour, which in turn would influence larval survival and life history processes that reduce fitness. This tool not only shows the value of using numerical models to predict animal behaviour in a complex environment, but also highlights the merit of using such models to predict anthropogenic impacts that would otherwise be difficult or too costly to obtain.NERCHR Wallingfor
Testing surfactants as additives for clay improvement: compaction and suction effects
Environmental Geotechnics (Joint TC106-TC215 Session)This paper presents an exploratory study on surfactants as additives to improve soil properties. It is hypothesized that surfactant molecules populate the air-water interfaces reducing surface tension and suction thus allowing a control of the mechanical response of the soil. Suction measurements by means of a high suction tensiometer, compaction tests and Atterberg limits were conducted in mixtures of sand and kaolin, with and without a surfactant solution. The results revealed a prominent effect on suction, but to a lesser extent on the Atterberg limits and compaction behavior (the maximum dry density). This targeted effect of the surfactants suggests its molecules populate, not only the air-water interfaces decreasing surface tension, but may be adsorbing to the clay particles and forming micelles in the pore water as well. Therefore the interplay between the three may influence the soil behavior.published_or_final_versio
Carbon dynamics of the Weddell Gyre, Southern Ocean
This is the final version of the article. Available from Wiley via the DOI in this record.The accumulation of carbon within the Weddell Gyre and its exchanges across the gyre boundaries are investigated with three recent full-depth oceanographic sections enclosing this climatically important region. The combination of carbon measurements with ocean circulation transport estimates from a box inverse analysis reveals that deepwater transports associated with Warm Deep Water (WDW) and Weddell Sea Deep Water dominate the gyre's carbon budget, while a dual-cell vertical overturning circulation leads to both upwelling and the delivery of large quantities of carbon to the deep ocean. Historical sea surface pCO2 observations, interpolated using a neural network technique, confirm the net summertime sink of 0.044 to 0.058±0.010PgCyr-1 derived from the inversion. However, a wintertime outgassing signal similar in size results in a statistically insignificant annual air-to-sea CO2 flux of 0.002±0.007PgCyr-1 (mean 1998-2011) to 0.012±0.024PgCyr-1 (mean 2008-2010) to be diagnosed for the Weddell Gyre. A surface layer carbon balance, independently derived from in situ biogeochemical measurements, reveals that freshwater inputs and biological drawdown decrease surface ocean inorganic carbon levels more than they are increased by WDW entrainment, resulting in an estimated annual carbon sink of 0.033±0.021PgCyr-1. Although relatively less efficient for carbon uptake than the global oceans, the summertime Weddell Gyre suppresses the winter outgassing signal, while its biological pump and deepwater formation act as key conduits for transporting natural and anthropogenic carbon to the deep ocean where they can reside for long time scales.NERCEuropean Union CarboOceanCarboChang
Cognitive architectures as Lakatosian research programmes: two case studies
Cognitive architectures - task-general theories of the structure and function of the complete cognitive system - are sometimes argued to be more akin to frameworks or belief systems than scientific theories. The argument stems from the apparent non-falsifiability of existing cognitive architectures. Newell was aware of this criticism and argued that architectures should be viewed not as theories subject to Popperian falsification, but rather as Lakatosian research programs based on cumulative growth. Newell's argument is undermined because he failed to demonstrate that the development of Soar, his own candidate architecture, adhered to Lakatosian principles. This paper presents detailed case studies of the development of two cognitive architectures, Soar and ACT-R, from a Lakatosian perspective. It is demonstrated that both are broadly Lakatosian, but that in both cases there have been theoretical progressions that, according to Lakatosian criteria, are pseudo-scientific. Thus, Newell's defense of Soar as a scientific rather than pseudo-scientific theory is not supported in practice. The ACT series of architectures has fewer pseudo-scientific progressions than Soar, but it too is vulnerable to accusations of pseudo-science. From this analysis, it is argued that successive versions of theories of the human cognitive architecture must explicitly address five questions to maintain scientific credibility
Vortex detection and quantum transport in mesoscopic graphene Josephson-junction arrays
We investigate mesoscopic Josephson junction arrays created by patterning
superconducting disks on monolayer graphene, concentrating on the high-
regime of these devices and the phenomena which contribute to the
superconducting glass state in diffusive arrays. We observe features in the
magnetoconductance at rational fractions of flux quanta per array unit cell,
which we attribute to the formation of flux-quantized vortices. The applied
fields at which the features occur are well described by Ginzburg-Landau
simulations that take into account the number of unit cells in the array. We
find that the mean conductance and universal conductance fluctuations are both
enhanced below the critical temperature and field of the superconductor, with
greater enhancement away from the graphene Dirac point.This work was financially supported by the Engineering
and Physical Sciences Research Council,
and an NPL/EPSRC Joint Postdoctoral Partnership
(RG61493).This is the accepted manuscript. The final version is available at http://journals.aps.org/prb/abstract/10.1103/PhysRevB.91.245418
Design and rationale of a multi-center, pragmatic, open-label randomized trial of antimicrobial therapy - the study of clinical efficacy of antimicrobial therapy strategy using pragmatic design in Idiopathic Pulmonary Fibrosis (CleanUP-IPF) clinical trial
Compelling data have linked disease progression in patients with idiopathic pulmonary fibrosis (IPF) with lung dysbiosis and the resulting dysregulated local and systemic immune response. Moreover, prior therapeutic trials have suggested improved outcomes in these patients treated with either sulfamethoxazole/ trimethoprim or doxycycline. These trials have been limited by methodological concerns. This trial addresses the primary hypothesis that long-term treatment with antimicrobial therapy increases the time-to-event endpoint of respiratory hospitalization or all-cause mortality compared to usual care treatment in patients with IPF. We invoke numerous innovative features to achieve this goal, including: 1) utilizing a pragmatic randomized trial design; 2) collecting targeted biological samples to allow future exploration of 'personalized' therapy; and 3) developing a strong partnership between the NHLBI, a broad range of investigators, industry, and philanthropic organizations. The trial will randomize approximately 500 individuals in a 1:1 ratio to either antimicrobial therapy or usual care. The site principal investigator will declare their preferred initial antimicrobial treatment strategy (trimethoprim 160 mg/ sulfamethoxazole 800 mg twice a day plus folic acid 5 mg daily or doxycycline 100 mg once daily if body weight is < 50 kg or 100 mg twice daily if ≥50 kg) for the participant prior to randomization. Participants randomized to antimicrobial therapy will receive a voucher to help cover the additional prescription drug costs. Additionally, those participants will have 4-5 scheduled blood draws over the initial 24 months of therapy for safety monitoring. Blood sampling for DNA sequencing and genome wide transcriptomics will be collected before therapy. Blood sampling for transcriptomics and oral and fecal swabs for determination of the microbiome communities will be collected before and after study completion. As a pragmatic study, participants in both treatment arms will have limited in-person visits with the enrolling clinical center. Visits are limited to assessments of lung function and other clinical parameters at time points prior to randomization and at months 12, 24, and 36. All participants will be followed until the study completion for the assessment of clinical endpoints related to hospitalization and mortality events. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02759120
Water dispersible microbicidal cellulose acetate phthalate film
BACKGROUND: Cellulose acetate phthalate (CAP) has been used for several decades in the pharmaceutical industry for enteric film coating of oral tablets and capsules. Micronized CAP, available commercially as "Aquateric" and containing additional ingredients required for micronization, used for tablet coating from water dispersions, was shown to adsorb and inactivate the human immunodeficiency virus (HIV-1), herpesviruses (HSV) and other sexually transmitted disease (STD) pathogens. Earlier studies indicate that a gel formulation of micronized CAP has a potential as a topical microbicide for prevention of STDs including the acquired immunodeficiency syndrome (AIDS). The objective of endeavors described here was to develop a water dispersible CAP film amenable to inexpensive industrial mass production. METHODS: CAP and hydroxypropyl cellulose (HPC) were dissolved in different organic solvent mixtures, poured into dishes, and the solvents evaporated. Graded quantities of a resulting selected film were mixed for 5 min at 37°C with HIV-1, HSV and other STD pathogens, respectively. Residual infectivity of the treated viruses and bacteria was determined. RESULTS: The prerequisites for producing CAP films which are soft, flexible and dispersible in water, resulting in smooth gels, are combining CAP with HPC (other cellulose derivatives are unsuitable), and casting from organic solvent mixtures containing ≈50 to ≈65% ethanol (EtOH). The films are ≈100 µ thick and have a textured surface with alternating protrusions and depressions revealed by scanning electron microscopy. The films, before complete conversion into a gel, rapidly inactivated HIV-1 and HSV and reduced the infectivity of non-viral STD pathogens >1,000-fold. CONCLUSIONS: Soft pliable CAP-HPC composite films can be generated by casting from organic solvent mixtures containing EtOH. The films rapidly reduce the infectivity of several STD pathogens, including HIV-1. They are converted into gels and thus do not have to be removed following application and use. In addition to their potential as topical microbicides, the films have promise for mucosal delivery of pharmaceuticals other than CAP
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