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Creutzfeldt-Jakob disease (CJD) is a fatal neurological illness for which accurate diagnosis is paramount. Real-time quaking-induced conversion (RT-QuIC) is a prion-specific assay with high sensitivity and specificity for CJD. The Canadian endpoint quaking-induced conversion (EP-QuIC) test is similar, but unlike RT-QuIC there is little data regarding its diagnostic utility in clinical practice. In this exploratory predictive value analysis of EP-QuIC in CJD, the negative predictive value (NPV) and positive predictive value (PPV) was 100% and 83%, respectively, with one false-positive result identified. Re-testing this sample with an optimized EP-QuIC protocol eliminated this false-positive result, leading to a PPV of 100%.
We develop a test, based on the Lagrange multiplier [LM] testing principle, for the value of the long memory parameter of a univariate time series that is composed of a fractionally integrated shock around a potentially broken deterministic trend. Our proposed test is constructed from data which are de-trended allowing for a trend break whose (unknown) location is estimated by a standard residual sum of squares estimator applied either to the levels or first differences of the data, depending on the value specified for the long memory parameter under the null hypothesis. We demonstrate that the resulting LM-type statistic has a standard limiting null chi-squared distribution with one degree of freedom, and attains the same asymptotic local power function as an infeasible LM test based on the true shocks. Our proposed test therefore attains the same asymptotic local optimality properties as an oracle LM test in both the trend break and no trend break environments. Moreover, this asymptotic local power function does not alter between the break and no break cases and so there is no loss in asymptotic local power from allowing for a trend break at an unknown point in the sample, even in the case where no break is present. We also report the results from a Monte Carlo study into the finite-sample behaviour of our proposed test.
Systemic uptake of organic compounds from roots to leaves follows a Gaussian distribution in relation to the lipophilicity, as measured by the log Kow. Quantification of compound uptake with different lipophilicities, and applied as a seed treatment that diffuses through the seed coat into the embryo during imbibition, has not been reported. The aim of this investigation was to quantify the uptake of non-ionic compounds into seeds of soybean and corn. A series of fluorescent piperonyl amides were synthesized and a novel combinatorial pharmacodynamic technique was developed that provided a range of compounds from log Kow 0.02 to 5.7. Seeds were treated with a mixture of amides, imbibed and compounds chemically extracted and quantified by high-performance liquid chromatography using a fluorescence detector. The maximum uptake efficiency of the applied amide mixture from whole soybean and corn seeds was 67% at log Kow 2.9, and 43% at log Kow 3.4, respectively. The critical partition coefficient for uptake for both species was <4.2 log Kow. Seeds were dissected and separated as soybean embryo and testa, and corn internal tissues (embryo + endosperm) or seed covering layers (pericarp + testa), and >75% of the amides were found in the soybean embryo or corn internal tissues compared with the covering layers at log Kow <4.2. The distribution of amides showed that the corn seed covering layer had similar hydrophilic/lipophilic properties as internal tissues, while soybean tissues had different hydrophilic/lipophilic properties. Collectively, the Gaussian uptake pattern for systemic uptake into plants was not found for either seed species.
The recently discovered orthorhombic allotrope of silicon, Si24, is an exciting prospective material for the future of solar energy due to a quasi-direct bandgap near 1.3 eV, coupled with the abundance and environmental stability of silicon. Synthesized via precursor Na4Si24 at high temperature and pressure (∼850 °C, 9 GPa), typical synthesis results have yielded polycrystalline samples with crystallites on the order of 20 μm. Several approaches to increase the crystal size have yielded success, including in-situ thermal spikes and refined selection of the starting materials. Microstructural analysis suggests that coherency exists between diamond silicon (d-Si) and Na4Si24. This hypothesis has led to the successful attempts at single crystal synthesis by selecting large crystals of d-Si along with metallic Na as the precursors rather than powdered and mixed precursor material. The new synthesis approach has yielded single crystals of Na4Si24 greater than 100 μm. These results represent a breakthrough in synthesis that enables further characterization and utility. The promise of Si24 for the future of solar energy generation and efficient electronics is strengthened through these advances in synthesis.
This paper discusses a pulse electroplating method for preparing copper (Cu)-coated gas diffusion electrodes (GDEs) for the electrochemical conversion of carbon dioxide (CO2) to hydrocarbons such as ethylene. Ionomer coating and air-plasma surface pre-treatments were explored as means of hydrophilizing the carbon surface to enable adhesion of electrodeposited material. The pulsed-current electrodeposition method used successfully generated copper and copper oxide micro- and nano-particles on the prepared surfaces. Copper(I) species identified on the ionomer-treated GDEs are presumed to be highly active for the selective generation of ethylene as compared to other gaseous byproducts of CO2 reduction. Conversely, copper catalysts deposited onto plasma-treated GDEs were found to have poor activity for hydrocarbon production, likely due to substantial metallic character. Of note, plasma treatment of an ionomer-treated GDE after copper plating yielded further improvements in catalytic activity and durability towards ethylene production.
Driving anxiety can range from driving reluctance to driving phobia, and 20% of young older adults experience mild driving anxiety, whereas 6% report moderate to severe driving anxiety. However, we do not know what impact driving anxiety has on health and well-being, especially among older drivers. This is problematic because there is a growing proportion of older adult drivers and a potential for driving anxiety to result in premature driving cessation that can impact on health and mortality. The purpose of the current study was to examine the impact of driving anxiety on young older adults’ health and well-being.
Data were taken from a longitudinal study of health and aging that included 2,473 young older adults aged 55–70 years. The outcome measures were mental and physical health (SF-12) and quality of life (WHOQOL-8).
Hierarchical multiple regression analyses demonstrated that driving anxiety was associated with poorer mental health, physical health, and quality of life, over and above the effect of socio-demographic variables. Sex moderated the effect of driving anxiety on mental health and quality of life in that, as driving anxiety increased, men and women were more likely to have lower mental health and quality of life, but women were more likely to have higher scores compared to men.
Further research is needed to investigate whether driving anxiety contributes to premature driving cessation. If so, self-regulation of driving and treating driving anxiety could be important in preventing or reducing the declines in health and quality of life associated with driving cessation for older adults affected by driving anxiety.
Older people with dementia are at increased risk of physical decline and falls. Balance and mood are significant predictors of falls in this population. The aim of this study was to determine the effect of a tailored home-based exercise program in community-dwelling older people with dementia.
Forty-two participants with mild to moderate dementia were recruited from routine health services. All participants were offered a six-month home-based, carer-enhanced, progressive, and individually tailored exercise program. Physical activity, quality of life, physical, and psychological assessments were administered at the beginning and end of the trial.
Of 33 participants (78.6%) who completed the six-month reassessment ten (30%) reported falls and six (18%) multiple falls during the follow-up period. At reassessment, participants had better balance (sway on floor and foam), reduced concern about falls, increased planned physical activity, but worse knee extension strength and no change in depression scores. The average adherence to the prescribed exercise sessions was 45% and 22 participants (52%) were still exercising at trial completion. Those who adhered to ≥70% of prescribed sessions had significantly better balance at reassessment compared with those who adhered to <70% of sessions.
This trial of a tailored home-based exercise intervention presents preliminary evidence that this intervention can improve balance, concern about falls, and planned physical activity in community-dwelling older people with dementia. Future research should determine whether exercise interventions are effective in reducing falls and elucidate strategies for enhancing uptake and adherence in this population.
The concepts of nature, culture and heritage are deeply entwined; their threads run together in some of our finest museums, in accounts of exploration and discovery, in the work of artists, poets andwriters, and in areas that are cherished and protected because of their landscapes and wildlife. The conservation ethic - placing a value on the natural environment - lies at the heart of the notion of "natural heritage", but we need to question how those values originated, were consolidated and ultimately moulded and changed over time. In a contemporary context the connections between nature andculture have sometimes become lost, fragmented, dislocated or misunderstood; where did "natural heritage" begin and how do we engage with the idea of "nature" today? The essays collected here re-evaluate the role of culture in developing the concept of natural heritage, reflecting on the shifts in its interpretation over the last 300 years.
Contributors: Martin Holdgate, Marie Addyman,E. Charles Nelson, Darrell Smith, Andrew Ramsey, Viktor Kouloumpis, Richard Milner, Gina Douglas, Penny Bradshaw, Arthur MacGregor, Chiara Nepi, Hannah Paddon, Stephen Hewitt, Gordon McGregor Reid, Ghillean T Prance, Peter Davis, Christopher Donaldson, Lucy McRobert, Sophie Darlington, Keith Scholey, Paul A. Roncken, Angus Lunn, Juliet Clutton-Brock, Tim Sands, Robert A. Lambert, James Champion,Erwin van Maanen, Heather Prince, Chris Loynes, Julie Taylor, Sarah Elmeligi, Samantha Finn, Owen Nevin, Jared Bowers, Kate Hennessy, Natasha Lyons, Mike Jeffries.