Byzantine Heterodoxy and the Search for Identities: Some Thoughts on Byzantine Iconoclasm

no abstrac

Byzantine Heterodoxy and the Search for Identities: Some Thoughts on Byzantine Iconoclasm

no abstrac

Stabilization of symmetry-protected long-range entanglement in stochastic quantum circuits

Long-range entangled states are vital for quantum information processing and quantum metrology. Preparing such entangled states by combining measurements with unitary gates has opened new possibilities for efficient protocols with finite-depth quantum circuits. The complexity of these algorithms is crucial for the resource requirements on a quantum device. The stability of the preparation protocols to perturbations decides the fate of their implementation in large-scale noisy quantum devices. In this work, we consider stochastic quantum circuits in one and two dimensions consisting of randomly applied unitary gates and local measurements. These quantum operations preserve a class of discrete local symmetries, which can be broken due to the stochasticity arising from timing and gate imperfections. In the absence of randomness, the protocol is known to generate a symmetry-protected long-range entangled state in a finite-depth circuit. In the general case, by studying the time evolution under this hybrid quantum circuit, we analyze the time to reach the target entangled state. We find two important time scales which we associate with the emergence of certain symmetry generators. The quantum trajectories embody the local symmetry with a time that scales logarithmically with system size, whereas global symmetries require exponentially long times to appear. We devise error-mitigation protocols that provide significant improvement on both time scales and investigate the stability of the algorithm to perturbations that naturally arise in experiments. We also generalize the protocol to realize the toric code and Xu-Moore states in two dimensions, and open avenues for future studies of anyonic excitations present in those systems. Our work paves the way for efficient error correction for quantum state preparation.Comment: 19 pages, 19 figures, 1 tabl

Delays in construction projects in Greece: Causes, effects and project management tools

Time overruns in construction projects is a global phenomenon and is commonly cited in Greece as well, calling for the implementation of sound and effective project management. Although construction development has presented significant prosperity the last decade, experience has showed that projects are running significantly over schedule raising the question of what the causes of such delays are and to what extent are contractors and other actors of the construction industry aware of certain project management tools and techniques that will facilitate the timely completion of a contract. The present dissertation examines and analyses the factors causing delays in large- and medium-scale projects in the private sector in Greece. It also aims to gain an insight of the Greek experience regarding project management tools and methods, the professionals' awareness of such tools and their willingness to adopt them. These are achieved through a questionnaire distributed to a number of participants in the construction industry and through interviews held with some of the respondents, with reference to a theoretical background

Ductility and strain rate-dependency of adhesively-bonded timber joints

One of the most important characteristics of load-bearing structures is ductility, i.e. the ability of a material or a structure to sustain inelastic deformation prior to failure, without loss of resistance. The topic of this PhD Thesis was to develop ductile adhesively bonded timber joints, in order to compensate for the inherent lack of ductility of timber. After the rate-dependent true tensile and compressive properties of the acrylic adhesive had been established (including Poisson ratio, ductility and recovery), two types of adhesively-bonded timber joints were experimentally studied in tension and compression: stiff epoxy and ductile acrylic joints. The latter ones exhibited lower stiffness but higher capacity and ductility, as explained by the extracted stresses and strains too. Furthermore, finite element (FE) models, including these strain rate-dependent properties of the acrylics, were developed to validate all the experimental results obtained and study the parametric effect of the different applied displacement rates on the acrylic joints. Extensive simulation using the developed FE models has shown their capacity to accurately predict the rate effect on bonded joints' mechanical response: stiffness, yield, ductility, ultimate failure. Finally, the behavior of the developed bonded joints over mechanical joints was analytically compared, based on Eurocode and the results confirmed the promising potential of the developed joint concept. To summarize, if ductile adhesives are used, it is possible to create ductile timber joints, which can perform better compared to other existing assembling techniques (i.e. mechanical fasteners or epoxy-adhesives) and their complex, rate-dependent behavior can be modeled with precision with the help of FE. This knowledge can lead to a broader and more efficient use of timber, contributing subsequently to achieving more sustainable modern structures

Is Atorvastatin Associated with New Onset Diabetes or Deterioration of Glycemic Control? Systematic Review Using Data from 1.9 Million Patients.

BACKGROUND: Current evidence indicates that statins increase the risk of new onset diabetes mellitus (NOD) and also deteriorate the glycemic control in patients with known diabetes mellitus (DM) after high-dose statin therapy. AIMS: The aim of this review was to explore the effect of atorvastatin in causing NOD or deteriorating glycemic control in patients with DM. METHODS: Two independent reviewers conducted the literature search, through PubMed database searching for articles published in English until April 2015, and only primary studies were included. RESULTS: Of the 919 articles identified in our original search, 33 met the criteria for this review encompassing 1,951,113 participants. Twenty articles examined dysregulation of DM due to atorvastatin. Half of them showed that there was no significant change in glycemic control in patients treated with atorvastatin. Other studies showed that fasting plasma glucose and HbA1c levels were increased by atorvastatin. Thirteen articles examined if atorvastatin causes NOD. The majority of these articles showed that patients who used atorvastatin had a higher dose-dependent risk of developing NOD. CONCLUSION: This systematic review suggests that there is an association between atorvastatin treatment and NOD. Moreover, it showed that atorvastatin in high dose causes worsening of the glycemic control in patients with DM

Association of matrix γ-carboxyglutamic acid protein levels with insulin resistance and Lp(a) in diabetes: A cross-sectional study.

AIMS: The risk of cardiovascular disease (CVD) and mortality is increased in patients with chronic kidney disease (CKD), with a background role of vascular calcification in the development of CVD also reported. Studies have demonstrated that high lipoprotein(a) (Lp(a)) levels accelerate the development of atherosclerolsis and are potentially involved in the vascular calcification. Matrix Gla Protein (MGP) seems to play an important role in vascular calcification. The aim of the study was to examine the potential association of MGP concentrations with Lp(a) and insulin resistance. METHODS: The study involved 100patients divided in four groups: 25 with both CKD stage 4 and Type2 Diabetes (DM) (Group-A), 25 with CKD4 without DM (Group-B), 25 non uremic patients with DM (Group-C) and 25 healthy subjects (Group-D). Serum glucose, Lp(a), MGP, plasma HBA1c and insulin were measured in all patients. Insulin resistance was estimated by the homeostasis model assessment equation (HOMA-IR). RESULTS: A significant positive linear association between MGP and Lp(a) levels (r=0.272, p=0.006) was noted, as well as between MGP and HOMA-IR levels (r=0.308, p=0.002). However, no significant linear association between Lp(a) and HOMA-IR levels was recorded. A similar positive association between MGP and insulin levels (r=0.204, p=0.042) was also found. CONCLUSION: This study concluded that diabetes coexisting with renal disease leads to extreme vascular calcification expressed by elevated MGP levels, resulting in higher frequency of cardiovascular disease in comparison to CKD patients without diabetes. The detected Lp(a) and MGP association in CKD4 patients may also represent the key to the complicated mechanism of their coexisting accelerated atherosclerosis and vascular calcification

Stabilization of symmetry-protected long-range entanglement in stochastic quantum circuits

Long-range entangled states are vital for quantum information processing and quantum metrology. Preparing such states by combining measurements with unitary gates opened new possibilities for efficient protocols with finite-depth quantum circuits. The complexity of these algorithms is crucial for the resource requirements on a large-scale noisy quantum device, while their stability to perturbations decides the fate of their implementation. In this work, we consider stochastic quantum circuits in one and two dimensions comprising randomly applied unitary gates and local measurements. These operations preserve a class of discrete local symmetries, which are broken due to the stochasticity arising from timing and gate imperfections. In the absence of randomness, the protocol generates a symmetry-protected long-range entangled state in a finite-depth circuit. In the general case, by studying the time evolution under this hybrid circuit, we analyze the time to reach the target entangled state. We find two important time scales that we associate with the emergence of certain symmetry generators. The quantum trajectories embody the local symmetry with a time scaling logarithmically with system size, while global symmetries require exponentially long times. We devise error-mitigation protocols that significantly lower both time scales and investigate the stability of the algorithm to perturbations that naturally arise in experiments. We also generalize the protocol to realize toric code and Xu-Moore states in two dimensions, opening avenues for future studies of anyonic excitations. Our results unveil a fundamental relationship between symmetries and dynamics across a range of lattice geometries, which contributes to a broad understanding of the stability of preparation algorithms in terms of phase transitions. Our work paves the way for efficient error correction for quantum state preparation

Histoire culturelle du monde byzantin, néo-hellénique et sud-est européen

Paolo Odorico, directeur d’études avec Roger David Scott, professeur à l’Université de MelbourneDimitris G. Apostolopoulos, directeur de recherche à l’Institut de recherches néo-helléniques du CNRS d’AthènesChristine Angelidi, directeur de recherche à l’Institut de recherches byzantines du CNRS d’Athènes Le but des séminaires était de présenter l’historiographie byzantine de deux époques différentes, qui peuvent être définies comme époques charnières : le VIe siècle, marqué par le passage de ..