31 research outputs found

    High-fidelity indirect readout of trapped-ion hyperfine qubits

    Full text link
    We propose and demonstrate a protocol for high-fidelity indirect readout of trapped ion hyperfine qubits, where the state of a 9Be+^9\text{Be}^+ qubit ion is mapped to a 25Mg+^{25}\text{Mg}^+ readout ion using laser-driven Raman transitions. By partitioning the 9Be+^9\text{Be}^+ ground state hyperfine manifold into two subspaces representing the two qubit states and choosing appropriate laser parameters, the protocol can be made robust to spontaneous photon scattering errors on the Raman transitions, enabling repetition for increased readout fidelity. We demonstrate combined readout and back-action errors for the two subspaces of 1.2−0.6+1.1×10−41.2^{+1.1}_{-0.6} \times 10^{-4} and 0−0+1.9×10−50^{+1.9}_{-0} \times 10^{-5} with 68% confidence while avoiding decoherence of spectator qubits due to stray resonant light that is inherent to direct fluorescence detection.Comment: 7 + 6 pages, 3 + 1 figure

    Exploring participatory visions of smart transport in Milton Keynes

    Get PDF
    This paper explores citizen concerns emerging in the design stage of MotionMap, a smart transport initiative developed in the context of a £16 million smart city programme. A city-wide sensing system integrated with other databases will provide real-time information about vehicular and pedestrian movement. The experience of a series of smart transport workshops in Milton Keynes suggests that citizens feel that they bear the cost of smart cities through potentially intrusive surveillance producing sacrifices in convenience and privacy, while the gains are captured by industrial and governmental actors. This distrust of surveillance through urban sensing systems is not inflexible. Such systems can gain legitimacy through a participatory approach where users legitimize the sensing system by taking an active role in providing transport data, as opposed to having it ‘harvested’ from them through passive or opportunistic mechanisms. Participatory approaches are challenging because users will engage only if the system can provide compelling benefits. A key contribution of this research comes from identifying that the benefits important to citizens are not necessarily measured in economic terms nor in terms of increased efficiency

    Using non-invasive biomarkers to identify hepatic fibrosis in people with type 2 diabetes mellitus: the Edinburgh type 2 diabetes study

    Get PDF
    BACKGROUND & AIMS: It is difficult to determine the different stages of non-alcoholic fatty liver disease without the use of invasive liver biopsy. In this study we investigated five non-invasive biomarkers used previously to detect hepatic fibrosis and determined the level of agreement between them in order to inform future research. METHODS: In the Edinburgh Type 2 Diabetes Study, a population-based cohort aged 60-74 years with type 2 diabetes, 831 participants underwent ultrasound assessment for fatty liver and had serum aspartate aminotransferase to alanine aminotransferase ratio (AST/ALT), aspartate to platelet ratio index (APRI), European Liver Fibrosis panel (ELF), Fibrosis-4 Score (FIB4) and liver stiffness measurement (LSM) measured. RESULTS: Literature based cut-offs yielded marked differences in the proportions of the cohort with probable liver fibrosis in the full cohort. Agreement between the top 5% of the distribution for each biomarker pair was poor. APRI and FIB4 had the best positive agreement at 76.4%, but agreement for all of the other serum biomarker pairs was between 18% and 34%. Agreement with LSM was poor (9-16%). CONCLUSIONS: We found poor correlation between the five biomarkers of liver fibrosis studied. Using the top 5% of each biomarker resulted in good agreement on the absence of advanced liver disease but poor agreement on the presence of advanced disease. Further work is required to validate these markers against liver biopsy and to determine their predictive value for clinical liver-related endpoints, in a range of different low and high risk population groups

    Addition of hyaluronic acid to the FIB-4 liver fibrosis score improves prediction of incident cirrhosis and hepatocellular carcinoma in Type 2 diabetes: The Edinburgh Type 2 Diabetes Study

    Get PDF
    Background: Type 2 diabetes is associated with increased risk of progression to cirrhosis and hepatocellular carcinoma (HCC) in people with chronic liver diseases, particularly non-alcoholic fatty liver disease (NAFLD). However, the absolute risk of progression is low so it is crucial to accurately identify patients who would benefit most from hepatology referral and intensified management. Current risk-stratification tools are sub-optimal and perform worse in people with diabetes.Aims: To determine whether the addition of complementary biomarker(s) to current NAFLD risk-stratification tools in people with Type 2 diabetes could improve the identification of people who are at increased risk of developing incident cirrhosis or HCC.Methods: The Edinburgh Type 2 diabetes Study (ET2DS) is a cohort study of men and women with Type 2 diabetes (n=1066, age 60-75 at baseline). Cases of cirrhosis and HCC were identified over 11-years of follow-up. Biomarkers were measured at baseline and year one and association with incident disease assessed using logistic regression.Results: Of existing risk-stratification scores tested, the Fibrosis-4 (FIB-4) index and the AST:platelet ratio index (APRI) performed best in this cohort. Addition of hyaluronic acid (cut-point ≥50μg/L) to FIB-4 (cut-point ≥1.3) maintained a false negative rate ≤25% and reduced the number of people incorrectly identified as ‘high-risk’ for incident disease by ~50%.Conclusions: The addition of hyaluronic acid to FIB-4 reduced the proportion of people inappropriately identified as ‘high-risk’ for development of cirrhosis/HCC in a community population of otherwise asymptomatic people with Type 2 diabetes. These findings require validation in independent cohorts

    γ-Glutamyltransferase, but not markers of hepatic fibrosis, is associated with cardiovascular disease in older people with type 2 diabetes mellitus: the Edinburgh Type 2 Diabetes Study

    Get PDF
    AIMS/HYPOTHESIS: We examined the association of prevalent and incident cardiovascular disease (CVD) with chronic liver disease in a cohort of community-based people with type 2 diabetes, in order to clarify the relationship between these two important conditions. METHODS: 1,066 participants with type 2 diabetes aged 60–75 years underwent assessment of a range of liver injury markers (non-specific injury, steatosis, steatohepatitis, fibrosis, portal hypertension). Individuals were followed up for incident cardiovascular events. RESULTS: At baseline there were 370/1,033 patients with prevalent CVD, including 317/1,033 with coronary artery disease (CAD). After a mean follow-up of 4.4 years there were 44/663 incident CVD events, including 27/663 CAD events. There were 30/82 CVD-related deaths. Risk of dying from or developing CVD was no higher in participants with steatosis than in those without (HR 0.90; 95% CI 0.40, 2.00; p > 0.05). The only notable relationship was with γ-glutamyltransferase (GGT) (incident CVD: adjusted HR for doubling GGT 1.24 [95% CI 0.97, 1.59] p = 0.086; incident CAD: adjusted HR 1.33 [95% CI 1.00, 1.78] p = 0.053), suggesting that in our study population, chronic liver disease may have little effect on the development of, or mortality from, CVD. CONCLUSIONS/INTERPRETATION: An independent association between GGT and CVD warrants further exploration as a potentially useful addition to current cardiovascular risk prediction models in diabetes. However, overall findings failed to suggest that there is a clinical or pathophysiological association between chronic liver disease and CVD in elderly people with type 2 diabetes. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00125-015-3575-y) contains peer-reviewed but unedited supplementary material, which is available to authorised users
    corecore