385 research outputs found
Jetting Micron-Scale Droplets onto Chemically Heterogeneous Surfaces
We report experiments investigating the behaviour of micron-scale fluid
droplets jetted onto surfaces patterned with lyophobic and lyophilic stripes.
The final droplet shape depends on the droplet size relative to that of the
stripes. In particular when the droplet radius is of the same order as the
stripe width, the final shape is determined by the dynamic evolution of the
drop and shows a sensitive dependence on the initial droplet position and
velocity. Numerical solutions of the dynamical equations of motion of the drop
provide a close quantitative match to the experimental results. This proves
helpful in interpreting the data and allows for accurate prediction of fluid
droplet behaviour for a wide range of surfaces.Comment: 14 pages, accepted for publication in Langmui
Control of drop positioning using chemical patterning
We explore how chemical patterning on surfaces can be used to control drop
wetting. Both numerical and experimental results are presented to show how the
dynamic pathway and equilibrium shape of the drops are altered by a hydrophobic
grid. The grid proves a successful way of confining drops and we show that it
can be used to alleviate {\it mottle}, a degradation in image quality which
results from uneven drop coalescence due to randomness in the positions of the
drops within the jetted array.Comment: 3 pages, 4 figure
Glasgow supported self-management trial (GSuST) for patients with moderate to severe COPD: randomised controlled trial
Objective To determine whether supported self management in chronic obstructive pulmonary disease (COPD) can reduce hospital readmissions in the United Kingdom
Simultaneous presentation of IgG4-related chronic peri-aortitis and coeliac disease in a patient with Marfan's Syndrome
Diblock copolymers at a homopolymer-homopolymer-interface: a Monte Carlo simulation
The properties of diluted symmetric A-B diblock copolymers at the interface
between A and B homopolymer phases are studied by means of Monte Carlo (MC)
simulations of the bond fluctuation model. We calculate segment density
profiles as well as orientational properties of segments, of A and B blocks,
and of the whole chain. Our data support the picture of oriented ``dumbbells'',
which consist of mildly perturbed A and B Gaussian coils. The results are
compared to a self consistent field theory (SCFT) for single copolymer chains
at a homopolymer interface. We also discuss the number of interaction contacts
between monomers, which provide a measure for the ``active surface'' of
copolymers or homopolymers close to the interface
Four patients with a history of acute exacerbations of COPD: implementing the CHEST/Canadian Thoracic Society guidelines for preventing exacerbations
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International License. The images or other third party material in this
article are included in the article’s Creative Commons license, unless indicated
otherwise in the credit line; if the material is not included under the Creative Commons
license, users will need to obtain permission from the license holder to reproduce the
material. To view a copy of this license, visit http://creativecommons.org/licenses/
by/4.0
OCT Assisted Quantification of Vitreous Inflammation in Uveitis
Purpose: Vitreous haze (VH) is a key marker of inflammation in uveitis but limited by its subjectivity. Optical coherence tomography (OCT) has potential as an objective, noninvasive method for quantifying VH. We test the hypotheses that OCT can reliably quantify VH and the measurement is associated with slit-lamp based grading of VH.
Methods: In this prospective study, participants underwent three repeated OCT macular scans to evaluate the within-eye reliability of the OCT vitreous intensity (VI). Association between OCT VI and clinical findings (including VH grade, phakic status, visual acuity [VA], anterior chamber cells, and macular thickness) were assessed.
Results: One hundred nineteen participants were included (41 healthy participants, 32 patients with uveitis without VH, and 46 patients with uveitis with VH). Within-eye test reliability of OCT VI was high in healthy eyes and in all grades of VH (intraclass correlation coefficient [ICC] > 0.79). Average OCT VI was significantly different between healthy eyes and uveitic eyes without and uveitic eyes with VH, and was associated with increasing clinical VH grade (P < 0.05). OCT VI was significantly associated with VA, whereas clinical VH grading was not. Cataract was also associated with higher OCT VI (P = 0.03).
Conclusions: OCT VI is a fast, noninvasive, objective, and automated method for measuring vitreous inflammation. It is associated with clinician grading of vitreous inflammation and VA, however, it can be affected by media opacities.
Translational Relevance: OCT imaging for quantifying vitreous inflammation shows high within-eye repeatability and is associated with clinical grading of vitreous haze. OCT measurements are also associated with visual acuity but may be affected by structures anterior to the acquisition window, such as lens opacity and other anterior segment changes
Submicrometer Pattern Fabrication by Intensification of Instability in Ultrathin Polymer Films under a Water-Solvent Mix
Dewetting of ultrathin (< 100 nm) polymer films, by heating above the glass
transition, produces droplets of sizes of the order of microns and mean
separations between droplets of the order of tens of microns. These relatively
large length scales are because of the weak destabilizing van der Waals forces
and the high surface energy penalty required for deformations on small scales.
We show a simple, one-step versatile method to fabricate sub-micron (>~100 nm)
droplets and their ordered arrays by room temperature dewetting of ultrathin
polystyrene (PS) films by minimizing these limitations. This is achieved by
controlled room temperature dewetting under an optimal mixture of water,
acetone and methyl-ethyl ketone (MEK). Diffusion of organic solvents in the
film greatly reduces its glass transition temperature and the interfacial
tension, but enhances the destabilizing field by introduction of electrostatic
force. The latter is reflected in a change in the exponent, n of the
instability length scale, {\lambda} ~h^n, where h is the film thickness and n =
1.51 \pm 0.06 in the case of water-solvent mix, as opposed to its value of 2.19
\pm 0.07 for dewetting in air. The net outcome is more than one order of
magnitude reduction in the droplet size as well as their mean separation and
also a much faster dynamics of dewetting. We also demonstrate the use of this
technique for controlled dewetting on topographically patterned substrates with
submicrometer features where dewetting in air is either arrested, incomplete or
unable to produce ordered patterns
Development of a Core Outcome Set for Clinical Trials in Non-infectious Uveitis of the Posterior Segment
Purpose: To develop an agreed upon set of outcomes known as a “core outcome set” (COS) for noninfectious uveitis of the posterior segment (NIU-PS) clinical trials. Design: Mixed-methods study design comprising a systematic review and qualitative study followed by a 2-round Delphi exercise and face-to-face consensus meeting. Participants: Key stakeholders including patients diagnosed with NIU-PS, their caregivers, and healthcare professionals involved in decision-making for patients with NIU-PS, including ophthalmologists, nurse practitioners, and policymakers/commissioners. Methods: A long list of outcomes was developed based on the results of (1) a systematic review of clinical trials of NIU-PS and (2) a qualitative study of key stakeholders including focus groups and interviews. The long list was used to generate a 2-round Delphi exercise of stakeholders rating the importance of outcomes on a 9-point Likert scale. The proportion of respondents rating each item was calculated, leading to recommendations of “include,” “exclude,” or “for discussion” that were taken to a face-to-face consensus meeting of key stakeholders at which they agreed on the final COS. Main Outcome Measure: Items recommended for inclusion in the COS for NIU-PS. Results: A total of 57 outcomes grouped in 11 outcome domains were presented for evaluation in the Delphi exercise, resulting in 9 outcomes directly qualifying for inclusion and 15 outcomes being carried forward to the consensus meeting, of which 7 of 15 were agreed on for inclusion. The final COS contained 16 outcomes organized into 4 outcome domains comprising visual function, health-related quality of life, treatment side effects, and disease control. Conclusions: This study builds on international work across the clinical trials community and our qualitative research to construct the world's first COS for NIU-PS. The COS provides a list of outcomes that represent the priorities of key stakeholders and provides a minimum set of outcomes for use in all future NIU-PS clinical trials. Adoption of this COS can improve the value of future uveitis clinical trials and reduce noninformative research. Some of the outcomes identified do not yet have internationally agreed upon methods for measurement and should be the subject of future international consensus development
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