3,231 research outputs found
Study comparing the orbital anatomy and histology of the microphthalmic and normal Syrian hamster; Cricetus (Mesocricetus) Auratus
Planar micromachined glass cantilevers utilising integrated Bragg Fabry-Perot cavities
Here we demonstrate a glass cantilever based on a unique micromachining and etching approach, combined with UV written Bragg gratings. We shall also discuss the increase in sensitivity by using two Bragg gratings to form Fabry-Pérot cavity. Cantilevers are in ultra sensitive force sensors used in applications such as Atomic Force Microscopy, mass sensing and acoustic transducers
Facet machining of silica waveguides with nanoscale roughness without polishing or lapping
To achieve low-loss free space coupling for integrated optics, device facets need to be smooth, free of chips and flat. The typical route for accomplishing these requirements is by traditional lapping and polishing. We report that high quality optical quality facets with a Sa = 4.9 nm can be machined using a simple dicing technique. In order to directly measure the scatter loss a device with a series of Bragg gratings is used to characterise the average interface loss per facet
Long-Term Progression of Structural Joint Damage in Early Rheumatoid Arthritis
Rheumatoid Arthritis (RA) is a chronic auto-immune disease that causes in
ammation in the
joints. Left uncontrolled, this prolonged in
ammation can lead to pain and structural damage,
resulting in erosions to the bones and total breakdown of the surrounding cartilage. Structural
joint damage, measured by plain radiographs, is an important outcome measure of RA. It provides
an objective marker of disease activity to assess any improvements or failures of treatments
in controlling for the disease. Increased long-term joint damage has been linked with increased
functional disability and decreased quality of life for RA patients. While a range of studies have
looked at radiographic outcomes from observational data, they tend to be restricted to historical
cohorts, with little long-term data on how radiographic progression may have changed in line
with changes in clinical management. Additionally, these studies have not used the appropriate
statistical methods to account for non-normal data distributions and within-patient variation
over time.
As a result, the main aim of this thesis is to investigate the long-term progression of structural
joint damage in patients with early RA. The speci c objectives were to; (1) investigate the
current evidence base to identify common methods in measuring and analysing radiographic
outcomes, (2) assess what statistical methods are most appropriate in modelling long-term radiographic
data, (3) use these models to understand the natural progression of radiographic
damage using data from two UK inception cohorts, and nally, (4) expand these models to
investigate the long-term relationship of radiographic damage with two important clinical outcomes;
disease activity and functional disability. The analysis is based on longitudinal data from
two UK prospective, multi-centre, early RA observational cohorts. These cohorts represent two
distinct eras in the management and treatment of RA, making them invaluable for investigating
how key RA outcomes have progressed in clinical practice over time.
Using multi-level count models, precise rates of radiographic progression for both cohorts are
presented. The models look at how seropositive RA and increased disease activity are related to
increased radiographic progression, and what impact this has on functional disability. The results
show that rates of radiological damage have declined dramatically in recent years. Possible
attributable factors to these declines include both milder disease and more e ective treatment
strategies.
Analysis of the earlier cohort (1986-2001) shows how seropositive RA and increased disease
activity lead to clinically meaningful increases in radiological damage. Conversely, their impact
on patients in the more recent cohort (2002-2011) suggest that their e ect on radiographic
progression is reduced, where increases in radiological damage were not larger than clinically
meaningful thresholds. This has large implications on the debate around the use of biologic
therapies in patients with less severe RA. However more data is sorely needed, particularly
long-term radiographic data from those patients on biologics treatments, before any de nitive
conclusions can be made.
The possible impact of these declines on functional disability appears to be relatively small. The
analysis shows that radiographic damage is more strongly associated with functional disability
in later disease, but there is little evidence to indicate that declines in radiographic damage has
lead to large improvements in long-term functional disability. These ndings are explored within
the framework of a dual-pathway model, which suggests that functional disability is caused by
two distinct mechanisms, either structural joint damage, or through increased pain. Research so
far has predominantly focused on pharmacological treatments in reducing in
ammation. More
research is needed to explore the role of psychosocial factors and pain perception in order to
create a more holistic treatment programme for RA patients
Resolved Young Binary Systems And Their Disks
We have conducted a survey of young single and multiple systems in the Taurus–Auriga star-forming region with the Atacama Large Millimeter Array (ALMA), substantially improving both the spatial resolution and sensitivity with which individual protoplanetary disks in these systems have been observed. These ALMA observations can resolve binary separations as small as 25–30 au and have an average 3σ detection level of 0.35 mJy, equivalent to a disk mass of 4 × 10−5 M ⊙ for an M3 star. Our sample was constructed from stars that have an infrared excess and/or signs of accretion and have been classified as Class II. For the binary and higher-order multiple systems observed, we detect λ = 1.3 mm continuum emission from one or more stars in all of our target systems. Combined with previous surveys of Taurus, our 21 new detections increase the fraction of millimeter-detected disks to over 75% in all categories of stars (singles, primaries, and companions) earlier than spectral type M6 in the Class II sample. Given the wealth of other information available for these stars, this has allowed us to study the impact of multiplicity with a much larger sample. While millimeter flux and disk mass are related to stellar mass as seen in previous studies, we find that both primary and secondary stars in binary systems with separations of 30–4200 au have lower values of millimeter flux as a function of stellar mass than single stars. We also find that for these systems, the circumstellar disk around the primary star does not dominate the total disk mass in the system and contains on average 62% of the total mass
Implications for Occupational Therapy Student Stress, Well-Being, and Coping: A Scoping Review
Scholarly literature and non-scholarly news sources have highlighted stressors in higher education. The rigor of occupational therapy education can compound student stress. Although the profession recognizes these stressors, insufficient literature exists regarding strategies to cope with and manage these sources of stress. This scoping review explored the literature examining stress and the implications for occupational therapy student well-being and coping, and also identified strategies for faculty to support student well-being. Using PRISMA Scoping Review guidelines, a systematic, multi-phase process was used to identify relevant literature. Databases searched included PubMed, CINAHL, PsycInfo, MEDLINE Complete, Web of Science, ERIC, and Education Database. Key search terms included components of well-being and coping. We discuss our scoping review approach to the literature search, data extraction, charting, and analysis. A sample of 15 articles met the inclusion criteria, with 1 article retracted during the analysis phase. The final sample of articles provided information about various components of stress, well-being, and coping. Analysis of these articles revealed the following themes: (1) well-being, (2) personal traits and skills, (3) stress, and (4) supportive pedagogy. Occupational therapy education is rigorous and demanding to ensure students are prepared to provide evidence-based care to their future clients. Although this demanding education may add to student stress, the profession must maintain high standards for patient safety. Results suggest there is an opportunity to support student wellness and learning within content delivery methods. By adjusting pedagogical approaches, instructors can support student wellness and impact learning
Resolved Young Binary Systems And Their Disks
We have conducted a survey of young single and multiple systems in the Taurus–Auriga star-forming region with the Atacama Large Millimeter Array (ALMA), substantially improving both the spatial resolution and sensitivity with which individual protoplanetary disks in these systems have been observed. These ALMA observations can resolve binary separations as small as 25–30 au and have an average 3σ detection level of 0.35 mJy, equivalent to a disk mass of 4 × 10−5 M ⊙ for an M3 star. Our sample was constructed from stars that have an infrared excess and/or signs of accretion and have been classified as Class II. For the binary and higher-order multiple systems observed, we detect λ = 1.3 mm continuum emission from one or more stars in all of our target systems. Combined with previous surveys of Taurus, our 21 new detections increase the fraction of millimeter-detected disks to over 75% in all categories of stars (singles, primaries, and companions) earlier than spectral type M6 in the Class II sample. Given the wealth of other information available for these stars, this has allowed us to study the impact of multiplicity with a much larger sample. While millimeter flux and disk mass are related to stellar mass as seen in previous studies, we find that both primary and secondary stars in binary systems with separations of 30–4200 au have lower values of millimeter flux as a function of stellar mass than single stars. We also find that for these systems, the circumstellar disk around the primary star does not dominate the total disk mass in the system and contains on average 62% of the total mass
The potential role of hedgehog signaling in the luminal/basal phenotype of breast epithelia and in breast cancer invasion and metastasis
© 2015 by the authors; licensee MDPI, Basel, Switzerland. The epithelium of the lactiferous ducts in the breast is comprised of luminal epithelial cells and underlying basal myoepithelial cells. The regulation of cell fate and transit of cells between these two cell types remains poorly understood. This relationship becomes of greater importance when studying the subtypes of epithelial breast carcinoma, which are categorized according to their expression of luminal or basal markers. The epithelial mesenchymal transition (EMT) is a pivotal event in tumor invasion. It is important to understand mechanisms that regulate this process, which bears relation to the normal dynamic of epithelial/basal phenotype regulation in the mammary gland. Understanding this process could provide answers for the regulation of EMT in breast cancer, and thereby identify potential targets for therapy. Evidence points towards a role for hedgehog signaling in breast tissue homeostasis and also in mammary neoplasia. This review examines our current understanding of role of the hedgehog-signaling (Hh) pathway in breast epithelial cells both during breast development and homeostasis and to assess the potential misappropriation of Hh signals in breast neoplasia, cancer stem cells and tumor metastasis via EMT
Influence of a supervised antenatal exercise program on estimates of heart rate responsiveness
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