2,166 research outputs found

    Fast, high fidelity information transmission through spin chain quantum wires

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    Spin chains have been proposed as quantum wires for information transfer in solid state quantum architectures. We show that huge gains in both transfer speed and fidelity are possible using a minimalist control approach that relies only a single, local, on-off switch actuator. Effective switching time sequences can be determined using optimization techniques for both ideal and disordered chains. Simulations suggest that effective optimization is possible even in the absence of accurate models.Comment: revtex4, 4 pages, 5 figure

    Carbocations and the Complex Flavor and Bouquet of Wine: Mechanistic Aspects of Terpene Biosynthesis in Wine Grapes.

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    Computational chemistry approaches for studying the formation of terpenes/terpenoids in wines are presented, using five particular terpenes/terpenoids (1,8-cineole, α-ylangene, botrydial, rotundone, and the wine lactone), volatile compounds (or their precursors) found in wine and/or wine grapes, as representative examples. Through these examples, we show how modern computational quantum chemistry can be employed as an effective tool for assessing the validity of proposed mechanisms for terpene/terpenoid formation

    Modulation of inherent dynamical tendencies of the bisabolyl cation via preorganization in epi-isozizaene synthase.

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    The relative importance of preorganization, selective transition state stabilization and inherent reactivity are assessed through quantum chemical and docking calculations for a sesquiterpene synthase (epi-isozizaene synthase, EIZS). Inherent reactivity of the bisabolyl cation, both static and dynamic, appears to determine the pathway to product, although preorganization and selective binding of the final transition state structure in the multi-step carbocation cascade that forms epi-isozizaene appear to play important roles

    The Use of the Blood Lactate Curve to Develop Training Intensity Guidelines for the Sports of Track and Field and Cross-Country

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    Int J Exerc Sci 5(2) : 148-159, 2012. The purpose of this study was to develop and field test a standardized system of training intensity guidelines for the sport of track and field/cross country, modeled after the standardized system of training intensity guidelines developed, adopted, and in use by U.S.A. Swimming. This study was quantitative and focused on the development and field-testing of standardized training intensity guidelines, based on the blood lactate curve and energy metabolism. The findings showed that as intensity increased so did participants’ blood lactate concentration, heart rate, and ratings of perceived exertion. A Pearson product-moment correlation analysis between the mean values of blood lactate concentration, heart rate, and ratings of perceived exertion, and the corresponding training intensity ranges revealed significant positive correlations between mean blood lactate values (r = 0.99, p \u3c 0.001), mean heart rate (r = 0.96, p \u3c 0.001); and ratings of perceived exertion (r = 0.99, p \u3c 0.005). Correlation analyses between heart rate and measures of blood lactate were positive (r = 0.70, p \u3e 0.05), as were heart rate and ratings of perceived exertion (r = 0.96, p \u3c 0.005). Measures of blood lactate were positively and significantly correlated to ratings of perceived exertion (r = 0.82, p \u3c 0.05). These findings validated the training intensity guidelines model

    Development of a disposable screen-printed amperometric biosensor based on glutamate dehydrogenase, for the determination of glutamate in clinical and food applications

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    A screen printed carbon electrode (SPCE) containing the electrocatalyst Meldola’s Blue (MB) has been investigated as the base transducer for a glutamate biosensor. The sandwich biosensor was fabricated by firstly depositing a chitosan (CHIT) layer onto the surface of the transducer (MB-SPCE), followed by glutamate dehydrogenase (GLDH): this device is designated GLDH-CHIT-MB-SPCE. NAD+ was added to buffer solutions prior to the measurement of glutamate. This biosensor was used in conjunction with amperometry in stirred solution at an applied potential of +0.1 V (vs. Ag/AgCl). Optimum conditions for the analysis of glutamate were found to be as follows: temperature, 35°C; buffer, pH 7; ionic strength, 75 mM; NAD+, 4 mM; CHIT 0.05% in 0.05 M HCl; GLDH, 30 U. The linear range of the biosensor was found to be 12.5 µM to 150 µM, the calculated limit of detection (based on three times signal to noise ratio) was 1.5 µM and the sensitivity was 0.44 nA/µM. The proposed biosensor was used to measure glutamate in serum before and after fortification with glutamate. The endogenous concentration of glutamate was found to be 1.68 mM and the coefficient of variation (CV) was 4.1%. The serum was then fortified with 2 mM of glutamate, and the resulting mean recovery was 96% with a CV of 3.3% (n = 6). An unfiltered beef OXO cube was analysed for monosodium glutamate (MSG) content. The endogenous content of MSG was 124.80 mg/g with a CV of 8.06%. The OXO cube solution was fortified with 0.935g (100 mM) of glutamate, the resulting mean recovery was 91% with a CV of 6.40 %

    Contemporary medical television and crisis in the NHS

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    This article maps the terrain of contemporary UK medical television, paying particular attention to Call the Midwife as its centrepiece, and situating it in contextual relation to the current crisis in the NHS. It provides a historical overview of UK and US medical television, illustrating how medical television today has been shaped by noteworthy antecedents. It argues that crisis rhetoric surrounding healthcare leading up to the passing of the Health and Social Care Act 2012 has been accompanied by a renaissance in medical television. And that issues, strands and clusters have emerged in forms, registers and modes with noticeable regularity, especially around the value of affective labour, the cultural politics of nostalgia and the neoliberalisation of healthcare

    Amperometric Screen-Printed Galactose Biosensor for Cell Toxicity Applications

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    © 2016, Copyright © Taylor & Francis Group, LLC. ABSTRACT: This paper reports the development and application of a biosensor for the amperometric determination of galactose in the presence of human hepatocellular carcinoma cells with and without a hepatotoxic agent. The biosensor was fabricated by drop-coating 1.5% cellulose acetate on a 3×3mm screen-printed carbon electrode followed by depositing 2 U of galactose oxidase. The electrodes dimensions were reduced to 3×0.5mm before measurements. Hepatocellular carcinoma cells were utilized for in vitro toxicity testing by evaluating the effect of paracetamol on galactose uptake. The amperometric responses to galactose indicated that the inhibition of uptake was directly proportional to the concentration of paracetamol following 24h of exposure to the hepatocellular carcinoma cells. These results demonstrate that the fabricated biosensor may be used for the real-time monitoring of cell metabolism and toxicity

    Patient safety in dentistry: development of a candidate 'never event' list for primary care

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    Introduction The 'never event' concept is often used in secondary care and refers to an agreed list of patient safety incidents that 'should not happen if the necessary preventative measures are in place'. Such an intervention may raise awareness of patient safety issues and inform team learning and system improvements in primary care dentistry. Objective To identify and develop a candidate never event list for primary care dentistry. Methods A literature review, eight workshops with dental practitioners and a modified Delphi with 'expert' groups were used to identify and agree candidate never events. Results Two-hundred and fifty dental practitioners suggested 507 never events, reduced to 27 distinct possibilities grouped across seven themes. Most frequently occurring themes were: 'checking medical history and prescribing' (119, 23.5%) and 'infection control and decontamination' (71, 14%). 'Experts' endorsed nine candidate never event statements with one graded as 'extreme risk' (failure to check past medical history) and four as 'high risk' (for example, extracting wrong tooth). Conclusion Consensus on a preliminary list of never events was developed. This is the first known attempt to develop this approach and an important step in determining its value to patient safety. Further work is necessary to develop the utility of this method

    Evaluation of the Fiscal Costs and Consequences of Alzheimer’s Disease in Germany:Microsimulation of Patients’ and Caregivers’ Pathways

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    Background: Alzheimer’s disease is a severe condition, impacting individual’s wellbeing and independence in daily activities. Informal care provision is common and of great value to societies but is not without negative externalities to households and the broader economy. Objectives: Estimate the lifetime incremental fiscal consequences of Alzheimer’s disease in community-based individuals and their informal caregivers. Setting: The fiscal consequences of Alzheimer’s disease was modeled using the German government and social security perspective. Participants: Synthetic cohort containing 1,000 pairs of people with Alzheimer’s disease and their informal caregivers, compared to 1,000 demographically identical pairs from the general population. Design: Disease progression was modeled using published equations and a state-transition microsimulation framework. Labor participation, financial support and paid taxes were estimated according to cognitive decline and caregiving responsibilities using German labor statistics and tax rates. Healthcare costs were sourced from several German publications. Costs and life-years were discounted at 3% annually. Measurements: Results are reported as lifetime incremental differences in total tax revenue and transfer payments between the cohort affected by Alzheimer’s disease and their general population analogues. Results: The Alzheimer’s disease-affected pair was associated with net incremental fiscal losses of €74,288 (85,037)totheGermangovernmentandsocialsecurityoverthelifetimeofpeoplewithAlzheimer’sdisease.Mostcostswerelosttaxesonemploymentearnings(48.485,037) to the German government and social security over the lifetime of people with Alzheimer’s disease. Most costs were lost taxes on employment earnings (48.4%) due to caregivers working reduced hours. Caregivers were estimated to earn €56,967 (65,209) less than their general population analogues. Financial support for informal and formal care accounted for 20.4%, and medical healthcare costs represented 24.0% of the incremental fiscal losses. Sensitivity analyses confirmed the robustness of the model results. In a cohort with early onset Alzheimer’s disease, incremental fiscal losses were predicted to be €118,533 ($114,209) over the lifetime of people with Alzheimer’s disease. Conclusions: Alzheimer’s disease externalities profoundly impact public economics for governments and should be considered to inform policy making and healthcare planning
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