1,188 research outputs found
Research on South-East Asia in Austria: The Project SEA-EU-NET at the Centre for Social Innovation (ZSI)
Topology of dynamical lattice configurations including results from dynamical overlap fermions
We investigate how the topological charge density in lattice QCD simulations
is affected by violations of chiral symmetry in different fermion actions. To
this end we compare lattice configurations generated with a number of different
actions including first configurations generated with exact overlap quarks. We
visualize the topological profiles after mild smearing. In the topological
charge correlator we measure the size of the positive core, which is known to
vanish in the continuum limit. To leading order we find the core size to scale
linearly with the lattice spacing with the same coefficient for all actions,
even including quenched simulations. In the subleading term the different
actions vary over a range of about 10 %. Our findings suggest that non-chiral
lattice actions at current lattice spacings do not differ much for this
specific observable related to topology, both among themselves and compared to
overlap fermions.Comment: 7 pages, talk presented at The XXIX International Symposium on
Lattice Field Theory - Lattice 2011, July 10-16, 2011, Squaw Valley, Lake
Tahoe, Californi
Preoperative CYFRA 21-1 and CEA as Prognostic Factors in Patients with Stage I Non-Small Cell Lung Cancer
Objective: To validate the prognostic value of preoperative levels of CYFRA 21-1, CEA and the corresponding tumor marker index (TMI) in patients with stage I non-small cell lung cancer (NSCLC). Methods: Two hundred forty stage I NSCLC patients (80 in pT1 and 160 in pT2; 100 squamous cell carcinomas, 91 adenocarcinomas, 32 large-cell carcinomas, 17 with other histologies; 171 males and 69 females) who had complete resection (R0) between 1986 and 2004 were included in the analysis. CYFRA 21-1 and CEA were measured using the Elecsys system (Roche) and AxSym-System (Abbott), respectively. Univariate analysis was performed using the Kaplan-Meier method to identify potential associations between survival and age, gender, CYFRA 21-1, CEA and TMI. Results: Overall 3- and 5-year survival rates were 74 and 64%, respectively. Male gender (p = 0.0009) and age 1 70 years (p = 0.0041) were associated with a worse prognosis; there were no differences between pT1 and pT2 nor between histological subtypes. Three- year survival was 72% for CYFRA 21-1 levels > 3.3 ng/ml versus 75% for levels 6.7 ng/ ml versus 75% for CEA 70 years were associated with a worse outcome, but elevated levels of CEA and CYFRA 21-1, and TMI risk were not. Copyright (C) 2008 S. Karger AG, Basel
Spreading the word or reducing the term spread? Assessing spillovers from euro area monetary policy
As a consequence of asset purchases by the European Central Bank (ECB), longer-term yields in the euro area decline, and spreads between euro area long-term yields narrow. To assess spillovers of these recent financial developments, we use a Bayesian variant of the global vector autoregressive (BGVAR) model with stochastic volatility and propose a novel mixture of zero impact and sign restrictions that we impose on the cross-section of the data. Both shocks generate positive and significant spillovers to industrial production in Central, Eastern and Southeastern Europe (CESEE) and other non-euro area EU member states. These effects are transmitted via the financial channel (mainly through interest rates and equity prices) and outweigh costs of appreciation pressure on local currencies vis-á-vis the euro (trade channel). While these results represent general trends, we also find evidence for both cross-country heterogeneity of effects within the euro area and region-specific spillovers thereof.Series: Department of Economics Working Paper Serie
Retention of mouth-to-mouth, mouth-to-mask and mouth-to-face shield ventilation
Background: Retention of mouth-to-mouth, mouth-to-mask and mouth-to-face shield ventilation techniques is poorly understood.Methods: A prospective randomised clinical trial was undertaken in January 2004 in 70 candidates randomly assigned to training in mouth-to-mouth, mouth-to-mask or mouth-to-face shield ventilation. Each candidate was trained for 10 min, after which tidal volume, respiratory rate, minute volume, peak airway pressure and the presence or absence of stomach inflation were measured. 58 subjects were reassessed 1 year later and study parameters were recorded again. Data were analysed with ANOVA, \textgreekq2 and McNemar tests.Results: Tidal volume, minute volume, peak airway pressure, ventilation rate and stomach inflation rate increased significantly at reassessment with all ventilation techniques compared with the initial assessment. However, at reassessment, mean (SD) tidal volume (960 (446) vs 1008 (366) vs 1402 (302) ml; p<0.05), minute volume (12 (5) vs 13 (7) vs 18 (3) l/min; p<0.05), peak airway pressure (14 (8) vs 17 (13) vs 25 (8) cm H2O; p<0.05) and stomach inflation rate (63% vs 58% vs 100%; p<0.05) were significantly lower with mouth-to-mask and mouth-to-face shield ventilation than with mouth-to-mouth ventilation. The ventilation rate at reassessment did not differ significantly between the ventilation techniques.Conclusions: One year after a single episode of ventilation training, lay persons tended to hyperventilate; however, the degree of hyperventilation and resulting stomach inflation were lower when a mouth-to-mask or a face shield device was employed. Regular training is therefore required to retain ventilation skills; retention of skills may be better with ventilation devices
Filtered topological structure of the QCD vacuum: Effects of dynamical quarks
We systematically compare filtering methods used to extract topological
structures on SU(3) lattice configurations. We show that there is a strong
correlation of the topological charge densities obtained by APE and Stout
smearing. To get rid of artifacts of these methods, we analyse structures that
are also seen by Laplace filtering and indeed identify artifacts for strong
smearing. The topological charge density in this combined analysis is more
fragmented in the presence of dynamical quarks. A power law exponent that
characterises the distribution of filtered topological clusters turns out to be
not far off the values of an instanton gas model.Comment: 7 pages, 6 figures, final version to appear in PL
Topology in dynamical Lattice QCD simulations
Lattice simulations of Quantum Chromodynamics (QCD), the quantum field theory which describes the interaction between quarks and gluons, have reached a point were contact to experimental data can be made. The underlying mechanisms, like chiral symmetry breaking or the confinement of quarks, are however still not understood.
This thesis focuses on topological structures in the QCD vacuum. Those are not only mathematically interesting but also closely related to chiral symmetry and confinement. We consider methods to identify these objects in lattice QCD simulations. Based on this, we explore the structures resulting from different discretizations and investigate the effect of a very strong electromagnetic field on the QCD vacuum
Better Uncertainty Calibration via Proper Scores for Classification and Beyond
With model trustworthiness being crucial for sensitive real-world
applications, practitioners are putting more and more focus on improving the
uncertainty calibration of deep neural networks. Calibration errors are
designed to quantify the reliability of probabilistic predictions but their
estimators are usually biased and inconsistent. In this work, we introduce the
framework of proper calibration errors, which relates every calibration error
to a proper score and provides a respective upper bound with optimal estimation
properties. This relationship can be used to reliably quantify the model
calibration improvement. We theoretically and empirically demonstrate the
shortcomings of commonly used estimators compared to our approach. Due to the
wide applicability of proper scores, this gives a natural extension of
recalibration beyond classification.Comment: Accepted at NeurIPS 202
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