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Improving the stability of organosiloxane smectic A liquid crystal random lasers using redox dopants
This report is focus on the development of liquid crystal (LC) vis
ible
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light scattering devices
for random lasers. These light
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scattering devices are based upon binary mixtures that consist of an
organosiloxane smectic A LC and a wide temperature range nematogen LC. Both the temperature range
of the smectic A phase and t
he dielectric anisotropy of the binary mixture are increased compared with
that of the neat organosiloxane compound. In the latter case, the increase in the dielectric anisotropy
results in a reduction of the magnitude of the electric field required to ind
uce a clear state.
Furthermore, it is found that the electric field threshold continues to decrease with increasing
concentration of the nematic compound. For the random laser devices, the pyrromethene 597 laser
dye was added to a mixture that was optimize
d for scattering and it was found that the absorption
properties of the dye becomes unstable in the presence of the electro
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hydrodynamic instabilities that
are required to generate scattering in the LC cells. This is believed to be due to electro
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chemical
reactions that occur at the electrodes. To avoid dye degradation and ensure repeatable electro
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optic
behaviour, a reduction
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oxidation (redox) couple is dispersed within the dye
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doped binary mixture. It is
shown that the addition of redox dopants helps to s
tabilize the dye in the scattering mixtures, and also
increases the long
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term repeatability of the scattering behaviour. Finally, we conclude by
characterizing the random laser emission of the dye
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doped binary mixture and demonstrate improved
stability.This is the author accepted manuscript. The final published version is available at http://www.sciencedirect.com/science/article/pii/S0925346715000816
Financial toxicity: a potential side effect of prostate cancer treatment among Australian men.
The purpose of this study was to understand the extent, nature and variability of the current economic burden of prostate cancer among Australian men. An online cross-sectional survey was developed that combined pre-existing economic measures and new questions. With few exceptions, the online survey was viable and acceptable to participants. The main outcomes were self-reported out-of-pocket costs of prostate cancer diagnosis and treatment, changes in employment status and household finances. Men were recruited from prostate cancer support groups throughout Australia. Descriptive statistical analyses were undertaken. A total of 289 men responded to the survey during April and June 2013. Our study found that men recently diagnosed (within 16 months of the survey) (n = 65) reported spending a median AU14 000) for their cancer treatment while 75% of men spent up to AU250 or less in out-of-pocket expenses and some men facing very high costs. On average, respondents in paid employment at diagnosis stated that they had retired 4-5 years earlier than planned
Cohort profile: a national, population-based cohort of children born after assisted conception in the UK (1992–2009): methodology and birthweight analysis
PURPOSE: To generate a large cohort of children born after assisted reproductive technology (ART) in the UK between 1992 and 2009, their naturally conceived siblings (NCS) and matched naturally conceived population (NCP) controls and linking this with health outcome data to allow exploration of the effects of ART. The effects of fresh and frozen embryo transfer on birth weight (BW) were analysed to test the validity of the cohort. PARTICIPANTS: Children recorded on the Human Fertilisation and Embryology Authority (HFEA) register as being born after ART between 1992 and 2009, their NCS and matched NCP controls linked to Office for National Statistics birth registration dataset (HFEA-ONS cohort). This cohort was further linked to the UK Hospital Episode Statistics database to allow monitoring of the child's post-natal health outcomes up to 2015 (HFEA-ONS-HES subcohort). FINDINGS TO DATE: The HFEA-ONS cohort consisted of 75 348 children born after non-donor ART carried out in the UK between 1 April 1992 and 31 July 2009 and successfully linked to birth registration records, 14 763 NCS and 164 823 matched NCP controls. The HFEA-ONS-HES subcohort included 63 877 ART, 11 343 NCS and 127 544 matched NCP controls further linked to health outcome data. The exemplar analysis showed that children born after fresh embryo transfers were lighter (BW difference: -131 g, 95% CI: -140 to -123) and those born after frozen embryo transfers were heavier (BW difference: 35 g, 95% CI: 19 to 52) than the NCP controls. The within-sibling analyses were directionally consistent with the population control analyses, but attenuated markedly for the fresh versus natural conception (BW difference: -54 g; 95% CI: -72 to -36) and increased markedly for the frozen versus natural conception (BW difference: 152 g; 95% CI: 113 to 190) analyses. FUTURE PLANS: To use this cohort to explore the relationship between ART conception and short-term and long-term health outcomes in offspring
Allocating the Burdens of Climate Action: Consumption-Based Carbon Accounting and the Polluter-Pays Principle
Action must be taken to combat climate change. Yet, how the costs of climate action should be allocated among states remains a question. One popular answer—the polluter-pays principle (PPP)—stipulates that those responsible for causing the problem should pay to address it. While intuitively plausible, the PPP has been subjected to withering criticism in recent years. It is timely, following the Paris Agreement, to develop a new version: one that does not focus on historical production-based emissions but rather allocates climate burdens in proportion to each state’s annual consumption-based emissions. This change in carbon accounting results in a fairer and more environmentally effective principle for distributing climate duties
Steps in the bacterial flagellar motor
The bacterial flagellar motor is a highly efficient rotary machine used by
many bacteria to propel themselves. It has recently been shown that at low
speeds its rotation proceeds in steps [Sowa et al. (2005) Nature 437,
916--919]. Here we propose a simple physical model that accounts for this
stepping behavior as a random walk in a tilted corrugated potential that
combines torque and contact forces. We argue that the absolute angular position
of the rotor is crucial for understanding step properties, and show this
hypothesis to be consistent with the available data, in particular the
observation that backward steps are smaller on average than forward steps. Our
model also predicts a sublinear torque-speed relationship at low torque, and a
peak in rotor diffusion as a function of torque
SCN1A variants from bench to bedside-improved clinical prediction from functional characterization
Variants in the SCN1A gene are associated with a wide range of disorders including genetic epilepsy with febrile seizures plus (GEFS+), familial hemiplegic migraine (FHM), and the severe childhood epilepsy Dravet syndrome (DS). Predicting disease outcomes based on variant type remains challenging. Despite thousands of SCN1A variants being reported, only a minority has been functionally assessed.
We review the functional SCN1A work performed to date, critically appraise electrophysiological measurements, compare this to in silico predictions, and relate our findings to the clinical phenotype.
Our results show, regardless of the underlying phenotype, that conventional in silico software correctly predicted benign from pathogenic variants in nearly 90%, however was unable to differentiate within the disease spectrum (DS vs. GEFS+ vs. FHM). In contrast, patch‐clamp data from mammalian expression systems revealed functional differences among missense variants allowing discrimination between disease severities. Those presenting with milder phenotypes retained a degree of channel function measured as residual whole‐cell current, whereas those without any whole‐cell current were often associated with DS (p = .024).
These findings demonstrate that electrophysiological data from mammalian expression systems can serve as useful disease biomarker when evaluating SCN1A variants, particularly in view of new and emerging treatment options in DS
Boosting Long-term Memory via Wakeful Rest: Intentional Rehearsal is not Necessary, Automatic Consolidation is Sufficient.
<div><p>People perform better on tests of delayed free recall if learning is followed immediately by a short wakeful rest than by a short period of sensory stimulation. Animal and human work suggests that wakeful resting provides optimal conditions for the consolidation of recently acquired memories. However, an alternative account cannot be ruled out, namely that wakeful resting provides optimal conditions for intentional rehearsal of recently acquired memories, thus driving superior memory. Here we utilised non-recallable words to examine whether wakeful rest boosts long-term memory, even when new memories could not be rehearsed intentionally during the wakeful rest delay. The probing of non-recallable words requires a recognition paradigm. Therefore, we first established, via Experiment 1, that the rest-induced boost in memory observed via free recall can be replicated in a recognition paradigm, using concrete nouns. In Experiment 2, participants heard 30 non-recallable non-words, presented as ‘foreign names in a bridge club abroad’ and then either rested wakefully or played a visual spot-the-difference game for 10 minutes. Retention was probed via recognition at two time points, 15 minutes and 7 days after presentation. As in Experiment 1, wakeful rest boosted recognition significantly, and this boost was maintained for at least 7 days. Our results indicate that the enhancement of memory via wakeful rest is <i>not</i> dependent upon intentional rehearsal of learned material during the rest period. We thus conclude that consolidation is <i>sufficient</i> for this rest-induced memory boost to emerge. We propose that wakeful resting allows for superior memory consolidation, resulting in stronger and/or more veridical representations of experienced events which can be detected via tests of free recall and recognition.</p></div
What cost components are relevant for economic evaluations of palliative care, and what approaches are used to measure these costs? A systematic review
BACKGROUND: It is important to understand the costs of palliative and end-of-life care in order to inform decisions regarding cost allocation. However, economic research in palliative care is very limited and little is known about the range and extent of the costs that are involved in palliative care provision. AIM: To undertake a systematic review of the health and social care literature to determine the range of financial costs related to a palliative care approach and explore approaches used to measure these costs. DESIGN: A systematic review of empirical literature with thematic synthesis. Study quality was evaluated using the Weight of Evidence Framework. DATA SOURCES: The databases CINAHL, Cochrane, PsycINFO and Medline were searched from 1995 to November 2015 for empirical studies which presented data on the financial costs associated with palliative care. RESULTS: A total of 38 papers met our inclusion criteria. Components of palliative care costs were incurred within four broad domains: hospital care, community or home-based care, hospice care and informal care. These costs could be considered from the economic viewpoint of three providers: state or government, insurers/third-party/not-for-profit organisations and patient and family and/or society. A wide variety of costing approaches were used to derive costs. CONCLUSION: The evidence base regarding the economics of palliative care is sparse, particularly relating to the full economic costs of palliative care. Our review provides a framework for considering these costs from a variety of economic viewpoints; however, further research is required to develop and refine methodologies
Prevalence and Predictors of Herbal Medicine Use Among Adults in the United States
Objective: To describe the prevalence of herbal medicine use among US adults and to assess factors associated with and predictors of herbal use. Design: The data for herbal products use were collected from the 2015 National Consumer Survey on the Medication Experience and Pharmacists’ Roles. Chi-square test was used to analyz factors associated with herbal use, and predictors of herbal use were assessed with logistic regression analysis. Results: Factors associated with herbal supplement use include age older than 70, having a higher than high school education, using prescription medications or over-thecounter (OTC) medications, and using a mail-order pharmacy.” All Disease state associated significantly with herbal use. Approximately thirty-eight percent of those who used herbals used prescription medications and 42% of those who used herbals also used an OTC medication. The most frequent conditions associated with herbal supplement use were a stroke (48.7%), cancer (43.1%), and arthritis (43.0%). Among herbal product users, factors that predicted use included having higher than school education, using OTC medications, using mail-order pharmacy, stroke, obesity, arthritis, and breathing problems. Conclusions: More than one-third of respondents reported using herbal supplements. Older age and higher education were associated with a higher use of herbal supplements. People with chronic diseases are more likely to use herbal medicines than others. OTC drug users and patients with stroke are more likely to use herbal medicines than others
Factors Associated with herb and dietary supplement use by young adults in the United States
<p>Abstract</p> <p>Background</p> <p>Little is known about the association between use of herbs and dietary supplements (HDS) and lifestyle/behavior factors in young adults in the US.</p> <p>Methods</p> <p>Analyzing the 2002 National Health Interview Survey (NHIS), we examined the patterns of HDS (excluding vitamins/minerals) use among young adults in the United States using descriptive statistics and logistic regression.</p> <p>Results</p> <p>In our sample of 18 to 30 year olds (n = 6666), 26% were current smokers, 24% were moderate/heavy drinkers, 43% had high physical activity, and 54% and 76% use prescription and over the counter (OTC) medications respectively. Non-vitamin, non-mineral HDS was used by 17% of the overall sample in the last 12 months. In the multivariable analysis, the lifestyle and behavioral factors associated with HDS use include: current smoking (odds ratio 1.41 95% CI [1.16–1.72]); being a former smoker (1.50 [1.15–1.95]); moderate/heavy alcohol use (2.02 [1.53–2.65]); high physical activity levels (2.45 [1.98–3.03]); and prescription medication use (1.51 [1.26–1.81]). Among HDS users, only 24% discussed their use with a health care professional.</p> <p>Conclusion</p> <p>Nearly one in five young adults report using non-vitamin/non-mineral HDS.</p
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