459 research outputs found
Highly coloured and electrophoretically active polymer microparticles via staggered dispersion polymerisation in supercritical carbon dioxide and dodecane
Devices featuring electrophoretic displays (EPD) have become extremely popular in recent years because of their low power consumption, high readability and thin display designs, but a product with a full colour gamut comparable with liquid crystal displays (LCDs) has not yet been commercialised. In this article, we demonstrate that staggering the addition of methyl methacrylate (MMA) monomer and low quantities of a coloured dye crosslinker is an effective route to producing well-defined and covalently-linked, strongly coloured PMMA microparticles in one-pot, via dispersion polymerisation in supercritical carbon dioxide (scCO2). This novel methodology is synthetically simple, readily scalable and has the added cachet of being cost effective because the functional molecules can be confined on the microparticle surface such that even at low concentrations, the resulting materials are brightly coloured. We then demonstrate the applicability of this approach to another functional comonomer/crosslinker system in 2-dimethylaminoethyl methacrylate (DMAEMA)/ethyleneglycol dimethacrylate (EGDMA), in this case allowing hierarchically structured ‘pomegranate-like’ microparticles with polarisable charge to be produced over a range of DMAEMA loadings as high as 44 wt%. Finally, the performance of these materials in out-of-plane EPD test cells is compared against analogues synthesised in dodecane. These tests revealed that the coloured microparticles fabricated in scCO2 performed as well as or better than their dodecane synthesised counterparts, consistently producing the cleanest white state and achieving effective colour switching over ten cycles
Bulletin No. 371 - Fifty Years of Dry Land Research at the Nephi Field Station
The Nephi Field Station is the oldest dry-Iand experimental farm in America still in operation. It was established in 1903 by action of the Utah legislature and has been in continuous operation since. Five other arid experimental farms were established in Utah at the same time (Widtsoe and Merrill 1905) but they were all discontinued prior to 1920 (Harris et al. 1920).
The Nephi Field Station has had a most interesting history, and it is worthy of note that many of the men who were closely associated with it during its early history subsequently distinguished themselves as outstanding leaders. The station came into being largely as a result of the efforts of Dr. John A. Widtsoe, noted irrigation and dry farm authority of the west until his death in 1952. Under his leadership a systematic investigation was undertaken in 1901 to determine the possibilities of farming without irrigation in Utah. The experimental farm at Nephi was established largely as a result of that study
Finding a way: long-term care homes to support dementia
An ageing demographic has increased the number of people with dementia. Although dementia is commonly
associated with memory loss, other early symptoms include difficulty with wayfinding. Dementia alters visuo-spatial
perception and the processes used to interpret the physical environment. The role of the design of the physical
environment for people with dementia has gained increased recognition. Despite this, design for dementia is often
overlooked, focusing on issues relating to physical impairment. This paper presents the results of a PhD study and aims to examine the role of the design of the physical environment in supporting wayfinding for people with dementia living in long-term care settings in Northern Ireland. Mixed methods combined the observation of wayfinding walks and conversational style interviews to elicit perspectives and experiences of residents with
dementia. The findings aim to promote well-being for those with dementia living in long-term care settings
A prospective cohort study assessing clinical referral management & workforce allocation within a UK regional medical genetics service
Abstract
Ensuring patient access to genomic information in the face of increasing demand requires clinicians to develop innovative ways of working. This paper presents the first empirical prospective observational cohort study of UK multi-disciplinary genetic service delivery. It describes and explores collaborative working practices including the utilisation and role of clinical geneticists and non-medical genetic counsellors. Six hundred and fifty new patients referred to a regional genetics service were tracked through 850 clinical contacts until discharge. Referral decisions regarding allocation of lead health professional assigned to the case were monitored, including the use of initial clinical contact guidelines. Significant differences were found in the cases led by genetic counsellors and those led by clinical geneticists. Around a sixth, 16.8% (109/650) of referrals were dealt with by a letter back to the referrer or re-directed to another service provider and 14.8% (80/541) of the remaining patients chose not to schedule an appointment. Of the remaining 461 patients, genetic counsellors were allocated as lead health professional for 46.2% (213/461). A further 61 patients did not attend. Of those who did, 86% (345/400) were discharged after one or two appointments. Genetic counsellors contributed to 95% (784/825) of total patient contacts. They provided 93.7% (395/432) of initial contacts and 26.8% (106/395) of patients were discharged at that point. The information from this study informed a planned service re-design. More research is needed to assess the effectiveness and efficiency of different models of collaborative multi-disciplinary working within genetics services. Keywords (MeSH terms)
Genetic Services, Genetic Counseling, Interdisciplinary Communication, Cohort Studies, Delivery of Healthcare, Referral and Consultation
Relationships of the Psychological Influence of Food and Barriers to Lifestyle Change to Weight and Utilization of Online Weight Loss Tools
Abstract: Introduction: The psychological influence of food (PFS) and perceived barriers to lifestyle change (PBLC) were considered as predictors of body mass index and website tool utilization (TU) in an online weight loss program. Materials and Methodology: An archival analysis of all (N = 1361) overweight/obese (BMI M = 31.6 + 6.24 kg/m 2), adult (M = 42.0 + 10.72 years) users (82.4 % female) of an evidence-based, multidisciplinary Internet weight loss program was performed. Predictor variables included: PFS and PBLC, age, and longest maintained weight loss in relation to 1) BMI 2
Towards Inflation in String Theory
We investigate the embedding of brane inflation into stable compactifications
of string theory. At first sight a warped compactification geometry seems to
produce a naturally flat inflaton potential, evading one well-known difficulty
of brane-antibrane scenarios. Careful consideration of the closed string moduli
reveals a further obstacle: superpotential stabilization of the
compactification volume typically modifies the inflaton potential and renders
it too steep for inflation. We discuss the non-generic conditions under which
this problem does not arise. We conclude that brane inflation models can only
work if restrictive assumptions about the method of volume stabilization, the
warping of the internal space, and the source of inflationary energy are
satisfied. We argue that this may not be a real problem, given the large range
of available fluxes and background geometries in string theory.Comment: 41 pages, harvmac; v2: results of appendix A extended to include
branes at angles, typos corrected, refs adde
Anomalous Dimensions and Non-Gaussianity
We analyze the signatures of inflationary models that are coupled to strongly
interacting field theories, a basic class of multifield models also motivated
by their role in providing dynamically small scales. Near the squeezed limit of
the bispectrum, we find a simple scaling behavior determined by operator
dimensions, which are constrained by the appropriate unitarity bounds.
Specifically, we analyze two simple and calculable classes of examples:
conformal field theories (CFTs), and large-N CFTs deformed by relevant
time-dependent double-trace operators. Together these two classes of examples
exhibit a wide range of scalings and shapes of the bispectrum, including nearly
equilateral, orthogonal and local non-Gaussianity in different regimes. Along
the way, we compare and contrast the shape and amplitude with previous results
on weakly coupled fields coupled to inflation. This signature provides a
precision test for strongly coupled sectors coupled to inflation via irrelevant
operators suppressed by a high mass scale up to 1000 times the inflationary
Hubble scale.Comment: 40 pages, 10 figure
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