175 research outputs found

    Numerical Analysis of Quasiholes of the Moore-Read Wavefunction

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    We demonstrate numerically that non-Abelian quasihole excitations of the ν=5/2\nu = 5/2 fractional quantum Hall state have some of the key properties necessary to support quantum computation. We find that as the quasihole spacing is increased, the unitary transformation which describes winding two quasiholes around each other converges exponentially to its asymptotic limit and that the two orthogonal wavefunctions describing a system with four quasiholes become exponentially degenerate. We calculate the length scales for these two decays to be ξU≈2.7ℓ0\xi_{U} \approx 2.7 \ell_0 and ξE≈2.3ℓ0\xi_{E} \approx 2.3 \ell_0 respectively. Additionally we determine which fusion channel is lower in energy when two quasiholes are brought close together.Comment: 4 pages, 3 figure

    Vegetation of the coastal dunes and wetland of Schinias National Park (NE Attica, Sterea Ellas, Greece)

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    The vegetation developing on the coastal sand dunes and wetland of Schinias National Park, a Natura 2000 Site, was studied following the Braun-Blanquet method. Vegetation units were delimited using cluster analysis and by applying the fidelity measure; the phi-coefficient was used for the definition of diagnostic species. The vegetation types distinguished (twenty associations, two sub-associations and thirteen communities not assigned formal rank), which belong to 18 alliances, 16 orders and 12 classes, are discussed and presented in phytosociological tables. Among them Mathiolo tricuspidatae-Anthemidetum tomentosae, Pistacio lentisci-Pinetum halepensis pinetosum pineae, Puccinellio festuciformis-Aeluropetum litoralis cressetosum creticae and Tamaricetum tetrandrae are described for the first time. The vegetation types recognized in the study area are linked to twelve EUNIS habitat types, nine of which are related to 13 Annex I habitat types (Directive 92/43/EEC), and one to a habitat type of national interest (72A0). One Annex I habitat type occurring in the study area has scattered presence in the Natura 2000 network in Greece (1420), two are infrequent (2190, 2260), two are rare (2230, 2270) and three are priority habitat types (1150, 2250, 2270)

    The incidence of myelodysplastic syndromes in Western Greece is increasing.

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    Descriptive epidemiology of the myelodysplastic syndromes (MDS) is always interesting and may reveal time-dependent and geographical variations, as well as occupational exposure. Epidemiological data in Greece are not available by now. We have collected and analyzed medical records of all patients with a documented diagnosis of MDS, performed by an expert hematologist and/or hematopathologist, in the geographical area of Western Greece, during the 20-year period, defined between 1990 and 2009. We have then calculated and described demographic and clinical features of the diagnosed MDS patient population, and assessed the incidence and prevalence rates of MDS in Western Greece, during the above-mentioned period. A total of 855 patients with newly diagnosed MDS have been identified. Refractory anemia was the most common subtype in both FAB and WHO classification systems and in both genders. Del-5q and RARS were more commonly encountered among females, and the dysplastic subtype of chronic myelomonocytic leukemia among males. Trisomy 8 was the most common single cytogenetic abnormality. The crude mean annual incidence rate of MDS was 6.0 per 100,000 inhabitants aged ≥15 years old (all subtypes according to FAB), and it was 4.8 per 100,000 when CMML and RAEB-T were excluded. Crude incidence rate was higher in rural than in urban areas, but this finding was not confirmed after age standardization. Age-standardized mean annual incidence rate in men was 7.9/100,000 and in women 3.4/100,000. A continuously increasing incidence rate of MDS has been observed throughout the study period

    Occupational, dietary, and other risk factors for myelodysplastic syndromes in Western Greece

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    PURPOSE: We have observed an increasing incidence of myelodysplastic syndromes (MDS) in the geographic area of Western Greece during the past two decades. The objective of this study was to investigate potential risk factors for the manifestation of MDS in this area of Greece. METHODS: A hospital-based case-control study was conducted in the public hospitals of the region. Participants were interviewed based on a questionnaire regarding demographics, occupational exposures, smoking, alcohol consumption, dietary, and domestic factors. RESULTS: A total of 228 individuals (126 cases, 102 controls) were recruited in this study. Univariate analysis showed that risk of MDS was associated with a family history of hematologic malignancy or solid tumor, exposure to pesticides, insecticides, herbicides, increased weekly intake of meat and eggs, and increased alcohol intake, whereas fruit intake had a protective effect. Analysis by pesticide ingredient showed a weak association of exposure to paraquat and glyphosate with the occurrence of MDS. Multivariate analysis showed that independent risk factors for the manifestation of MDS were family history of solid tumor (OR 2.47, 95% CI 1.32-4.65), meat intake for ≥5 days/week (OR 2.67, 95% CI 1.05-6.80) and exposure to pesticides (OR 3.25, 95% CI 1.73-6.11). CONCLUSIONS: Exposure to pesticides is a major risk factor of MDS in Western Greece. Family history of solid tumor and increased meat intake also appear to play a role in the pathogenesis of MDS. Public health authorities should implement policies to advise and protect farmers from the harmful effects of agrochemicals. Emphasis should also be given to health promotion advice including healthy eating

    Does change in health-related quality of life score predict survival? Analysis of EORTC 08975 lung cancer trial

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    Background:Little is known about whether changes in health-related quality of life (HRQoL) scores from baseline during treatment also predict survival, which we aim to investigate in this study.Methods:We analysed data from 391 advanced non-small-cell lung cancer (NSCLC) patients enrolled in the EORTC 08975 study, which compared palliative chemotherapy regimens. HRQoL was assessed at baseline and after each chemotherapy cycle using the EORTC QLQ-C30 and QLQ-LC13. The prognostic significance of HRQoL scores at baseline and their changes over time was assessed with Cox regression, after adjusting for clinical and socio-demographic variables.Results:After controlling for covariates, every 10-point increase in baseline pain and dysphagia was associated with 11% and 12% increased risk of death with hazard ratios (HRs) of 1.11 and 1.12, respectively. Every 10-point improvement of physical function at baseline (HR=0.93) was associated with 7% lower risk of death. Every 10-point increase in pain (HR=1.08) was associated with 8% increased risk of death at cycle 1. Every 10-point increase in social function (HR=0.91) at cycle 2 was associated with 9% lower risk of death.Conclusions:Our findings suggest that changes in HRQoL scores from baseline during treatment, as measured on subscales of the EORTC QLQ-C30 and QLQ-LC13, are significant prognostic factors for survival
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