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Significant progress has been made in characterizing the biological changes occurring in preclinical Alzheimer's disease (AD). Cognitive dysfunction has been viewed, however, as a late-stage phenomenon, despite increasing evidence...
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Significant progress has been made in characterizing the biological changes occurring in preclinical Alzheimer's disease (AD). Cognitive dysfunction has been viewed, however, as a late-stage phenomenon, despite increasing evidence that changes may be detected in the decades preceding dementia. In the absence of comprehensive evidence-based guidelines for preclinical cognitive assessment, longitudinal cohort and neuroimaging studies have been reviewed to determine the temporal order and brain biomarker correlates of specific cognitive functions. Episodic memory decline was observed to be the most salient cognitive function, correlating with high levels of amyloid deposition and hypoconnectivity across large-scale brain networks. Prospective studies point to early decline in both episodic and semantic memory processing as well as executive functions in the predementia period. The cognitive tests have, however, been principally those used to diagnose dementia. New procedures are required which target more finely the medial temporal lobe subregions first affected by clinically silent AD pathology. (C) 2016 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.
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By applying the lenses of institutional work, this study presents an empirical analysis on how agents create and manage a hybrid virtual organization to provide an innovative solution to the problem of the lack of occupational hea...
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By applying the lenses of institutional work, this study presents an empirical analysis on how agents create and manage a hybrid virtual organization to provide an innovative solution to the problem of the lack of occupational health (OH) services among small businesses. We specifically focus on how these actors exploit and balance the prescriptions of different logics within this hybrid organization. Our qualitative study showed that the funders manage this virtual social enterprise through two main strategies: 'commitment to the social mission' and 'support for the social mission'. The first strategy shows how the social mission helped a diverse group of funders and employees to work together as a team. The second strategy assists these actors to grant the maintenance and justify the existence of this novel organization, which provides immense societal benefits but could not support itself financially. This article shows how a hybrid organizations' capacity for innovation and societal advantages depends on the ability to rely on multiple logics and simultaneously to shift the attention on the social mission as a catalytic force for its survival.
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Rather than accept the mainstream view that the state needs need to be brought back in to regional thinking, the paper argues that the state - and the analysis of it - is restricting understandings of urban and regional change and...
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Rather than accept the mainstream view that the state needs need to be brought back in to regional thinking, the paper argues that the state - and the analysis of it - is restricting understandings of urban and regional change and leading to a state-territorial trap. Analysing over 40 years of literature on growth-oriented regionalism, the paper reveals important blind spots in the approaches to researching regions (and other forms of place-making) and the role of business in regional development, planning and governance. Presenting a comparison of two spatial governance projects in the UK - The Peel Group's Atlantic Gateway Strategy and UK government's Local Enterprise Partnerships - it is revealed how business-orchestrated regionalism is a new empirical reality, but one we are ill-equipped to understand. It argues that we need to move beyond the conceptual and methodological lock-in of business-as-usual approaches to start 'seeing like a business' and revealing the practical politics and pragmatism by which actors - both state and business - are engaging to effect regional change and shape regional futures.
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Government, local authority and industry initiatives to improve the energy efficiency of housing stocks are central to national and international commitments to reduce carbon dioxide emissions. To be effective, initiatives need to...
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Government, local authority and industry initiatives to improve the energy efficiency of housing stocks are central to national and international commitments to reduce carbon dioxide emissions. To be effective, initiatives need to target homes which, given their location, size, fuel type and occupancy, use more energy than expected. This paper illustrates how energy efficiency benchmarks can be developed that account for these factors and highlights the shortcomings of relying on simple energy consumption statistics. The study uses existing data (with national coverage) and the measured electricity and gas consumption of groups consisting of, on average, 500-700 households to benchmark and track domestic gas and electricity consumption across England. Multiple regression models, which account for 65 % of the variation in domestic gas consumption and 73 % of domestic electricity variation, are used to derive the benchmarks. The actual gas and electricity consumption of each group of homes is compared against the derived benchmark and an energy efficiency index presented. The approach enables changes in energy efficiency to be tracked temporally, for example to assess the effectiveness of government, local authority or industry initiatives. National and city-scale patterns of energy efficiency are also discussed.
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Algorithmic methods can successfully automate the proof, and even the discovery, of a large class of identities involving sums of hypergeometric terms. In particular, the Wilf-Zeilberger (WZ) algorithm is a uniform framework for a...
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Algorithmic methods can successfully automate the proof, and even the discovery, of a large class of identities involving sums of hypergeometric terms. In particular, the Wilf-Zeilberger (WZ) algorithm is a uniform framework for a substantial class of hypergeometric summation problems. This algorithm can produce a rational function certificate that can, on the face of it, be used to verify the result by routine algebraic manipulations, independently of the working of the algorithm that discovered it. It is therefore very natural to consider using this certificate to produce, by automated means, a rigorous deductive proof in an interactive theorem prover. However, naive presentations of the WZ method tend to gloss over trivial-looking but rather knotty questions about zero denominators, which makes their rigorous formalization tricky and their ultimate logical justification somewhat obscure. We describe how we have handled these difficulties to produce rigorous WZ proofs inside the HOL Light theorem prover.
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Mr Litvinenko died on 23 November 2006, having been poisoned with polonium-210 on 1 November, with evidence of a previous poisoning attempt during October 2006. Measurements of Po-210 in urine samples were made for a large number ...
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Mr Litvinenko died on 23 November 2006, having been poisoned with polonium-210 on 1 November, with evidence of a previous poisoning attempt during October 2006. Measurements of Po-210 in urine samples were made for a large number of people to determine whether they may have been contaminated. In the majority of cases, measured levels were attributable to the presence of Po-210 from normal dietary sources. For a small number of cases, elevated levels provided evidence of direct contamination associated with the poisonings. For one individual, while estimated doses were below thresholds for irreversible organ damage, a notably increased risk of cancer can be inferred. The use of the chelating agent, unithiol, to increase Po-210 excretion in this case was only moderately effective in reducing doses received.
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Relational regions in the making': institutionalizing new regional geographies of higher education. Regional Studies. This paper advances current debates on relational regions and higher education through a unique focus on the ris...
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Relational regions in the making': institutionalizing new regional geographies of higher education. Regional Studies. This paper advances current debates on relational regions and higher education through a unique focus on the rise of transregional university alliances. It examines the formation of university research and training consortia to make a series of wider arguments about the new spatialities of higher education praxis, the construction of new regional identities and processes of institutionalizing relational regions. Our research shows new partnership working between universities to be conducive to the weakening of fixed regional territories. The paper then illustrates how and why some relational imaginaries are beginning to crystallize into harder institutional forms, before revealing significant political-economic and societal implications arising from new institutional geographies of higher education. Furthermore, our research reveals the concerted theoretical and empirical attention required to develop vocabulary and frameworks better able to comprehend emergent regional worlds. For our part, we distinguish between territorial, archipelagic, de facto and constellatory regionalism to exact more precise interpretations of unfolding configurations of relational regions and a new conceptual perspective on the increasingly complex spatialities characterizing and shaping our globalizing world.
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The global fight against Alzheimer's disease (AD) poses unique challenges for the field of neuropsychology. Along with the increased focus on early detection of AD pathophysiology, characterizing the earliest clinical stage of the...
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The global fight against Alzheimer's disease (AD) poses unique challenges for the field of neuropsychology. Along with the increased focus on early detection of AD pathophysiology, characterizing the earliest clinical stage of the disease has become a priority. We believe this is an important time for neuropsychology to consider how our approach to the characterization of cognitive impairment can be improved to detect subtle cognitive changes during early-stage AD. The present article aims to provide a critical examination of how we define and measure cognitive status in the context of aging and AD. First, we discuss pitfalls of current methods for defining cognitive impairment within the context of research shifting to earlier (pre)symptomatic disease stages. Next, we introduce a shift towards a more continuous approach for identifying early markers of cognitive decline and characterizing progression and discuss how this may be facilitated by novel assessment approaches. Finally, we summarize potential implications and challenges of characterizing cognitive status using a continuous approach.
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Herein waste biomass (blackberry pomace) was physicochemically characterized along with its thermochemical products. This is coupled with the evaluation of the kinetic triplet (activation energy, pre-exponential constant, and the ...
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Herein waste biomass (blackberry pomace) was physicochemically characterized along with its thermochemical products. This is coupled with the evaluation of the kinetic triplet (activation energy, pre-exponential constant, and the rate of reaction) and thermal predictions for the combustion process for the first time via the AKTS thermokinetics package. The main kinetic modeling method employed was the differential isoconversional analysis; however, the Flynn-Wall-Ozawa and ASTM E-698 methods were used as comparisons. The model was developed and validated from experimental DSC and TGA data, resulting in an excellent match (R-2 = 0.99544 and 0.99194, respectively). The activation energies were evaluated using the ASTM-E698 method (88.64 kJ mol(-1)) and Flynn-Wall-Ozawa methods (50-140 kJ mol(-1)). The differential isoconversional method showed that activation energy values were in the range of 84-197 kJ mol(-1) for the combustion of berry pomace. Isothermal predictions based on the model were indicated at temperatures of 560 and 600 degrees C; the reaction had achieved 100% completion (a = 1) after 30 and 6 min, respectively. For the nonisothermal prediction, the heating rates of 50, 75, and 100 degrees C/min have a two-stage rate profile with a maximum peak in the first stage of the reaction. Thereafter, the reaction rate increases once again but not to the same effect as the first initial stage. For instance, at 100 degrees C/min, stages 1 and 2 are reported as 0.005381 and 0.005148 s(-1),respectively. Overall, this study demonstrates the success of the approach in modeling the thermochemical conversion of berry pomace as waste stream biomass.
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The thermal stability of anatase titanium dioxide (TiO2) is a prerequisite to fabricate photocatalyst-coated indoor building materials for use in antimicrobial and self-cleaning applications under normal room light illumination. M...
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The thermal stability of anatase titanium dioxide (TiO2) is a prerequisite to fabricate photocatalyst-coated indoor building materials for use in antimicrobial and self-cleaning applications under normal room light illumination. Metal doping of TiO2 is an appropriate way to control the anatase to rutile phase transition (ART) at high processing temperatures. In this work, ART of indium (In)-doped TiO2 (In-TiO2) was investigated in detail in the range of 500-900 degrees C. In-TiO2 (In mol % = 0-16) was synthesized via a modified sol-gel approach. These nanoparticles were further characterized by means of powder X-ray diffraction (XRD), Raman, photoluminescence (PL), transient photocurrent response, and X-ray photoelectron spectroscopy (XPS) techniques. XRD results showed that the anatase phase was maintained up to 64% by 16 mol % of In doping at 800 degrees C of calcination temperature. XPS results revealed that the binding energies of (Ti 2p(1/2 )and Ti 2p(3/2)) were red-shifted by In doping. The influence of In doping on the electronic structure and oxygen vacancy formation of anatase TiO2 was studied using density functional theory corrected for on-site Coulomb interactions (DFT+U). First-principles results showed that the charge-compensating oxygen vacancies form spontaneously at sites adjacent to the In dopant. DFT+U calculations revealed the formation of In - Ss states in the band gap of the anatase host. The formation of In2O3 at the anatase surface was also examined using a slab model of the anatase (101) surface modified with a nanocluster of composition In4O6. The formation of a reducing oxygen vacancy also has a moderate energy cost and results in charge localization at In ions of the supported nanocluster. PL and photocurrent measurements suggested that the charge carrier recombination process in TiO2 was reduced in the presence of In dopant. The photocatalytic activity of 2% In-TiO2 calcined at 700 degrees C is more comparable with that of pure anatase.
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