84 research outputs found
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Information Society Strategies in the European Context: The Case of Greece
This article sets out to analyze the policies adopted by the Greek government in its effort to accelerate the pace of reform towards a knowledge-based economy. These policies have to take into account the position that the country occupies within the emerging information society and, of course, the opportunities created by EU initiatives that aim to promote economic competitiveness and reduce regional disparities. Within this framework Greek policy makers have recognized the need for a coordinated, coherent and integrated approach, which attempts to diminish inequalities both within the country and with respect to other European Union economies. What emerges as a distinctive feature of the Greek information society strategy is the emphasis placed on the pivotal role of the state and the adoption of active interventionist policies
Is there Correlation between Fine Structure and Dark Energy Cosmic Dipoles?
We present a detailed analysis (including redshift tomography) of the cosmic
dipoles in the Keck+VLT quasar absorber and in the Union2 SnIa samples. We show
that the fine structure constant cosmic dipole obtained through the Keck+VLT
quasar absorber sample at level is anomalously aligned with the
corresponding dark energy dipole obtained through the Union2 sample at
level. The angular separation between the two dipole directions is
. We use Monte Carlo simulations to find the
probability of obtaining the observed dipole magnitudes with the observed
alignment, in the context of an isotropic cosmological model with no
correlation between dark energy and fine structure constant . We find
that this probability is less than one part in . We propose a simple
physical model (extended topological quintessence) which naturally predicts a
spherical inhomogeneous distribution for both dark energy density and fine
structure constant values. The model is based on the existence of a recently
formed giant global monopole with Hubble scale core which also couples
non-minimally to electromagnetism. Aligned dipole anisotropies would naturally
emerge for an off-centre observer for both the fine structure constant and for
dark energy density. This model smoothly reduces to \lcdm for proper limits of
its parameters. Two predictions of this model are (a) a correlation between the
existence of strong cosmic electromagnetic fields and the value of and
(b) the existence of a dark flow on Hubble scales due to the repulsive gravity
of the global defect core (`Great Repulser') aligned with the dark energy and
dipoles. The direction of the dark flow is predicted to be towards the
spatial region of lower accelerating expansion. Existing data about the dark
flow are consistent with this prediction.Comment: 14 pages 11 figures (two column revtex). Aceepted in Phys. Rev. D (to
appear). Significant extensions (mostly on section 4 on the theoretical
model), added references, corrected typos. The data, updated mathematica and
C program files used for the numerical analysis may be downloaded from
http://leandros.physics.uoi.gr/defsdipole
Natural and Nature-Derived Products Targeting Human Coronaviruses
The ongoing pandemic of severe acute respiratory syndrome (SARS), caused by the SARS-CoV-2 human coronavirus (HCoV), has brought the international scientific community before a state of emergency that needs to be addressed with intensive research for the discovery of pharmacological agents with antiviral activity. Potential antiviral natural products (NPs) have been discovered from plants of the global biodiversity, including extracts, compounds and categories of compounds with activity against several viruses of the respiratory tract such as HCoVs. However, the scarcity of natural products (NPs) and small-molecules (SMs) used as antiviral agents, especially for HCoVs, is notable. This is a review of 203 publications, which were selected using PubMed/MEDLINE, Web of Science, Scopus, and Google Scholar, evaluates the available literature since the discovery of the first human coronavirus in the 1960s; it summarizes important aspects of structure, function, and therapeutic targeting of HCoVs as well as NPs (19 total plant extracts and 204 isolated or semi-synthesized pure compounds) with anti-HCoV activity targeting viral and non-viral proteins, while focusing on the advances on the discovery of NPs with anti-SARS-CoV-2 activity, and providing a critical perspective
Parametrization for the Scale Dependent Growth in Modified Gravity
We propose a scale dependent analytic approximation to the exact linear
growth of density perturbations in Scalar-Tensor (ST) cosmologies. In
particular, we show that on large subhorizon scales, in the Newtonian gauge,
the usual scale independent subhorizon growth equation does not describe the
growth of perturbations accurately, as a result of scale-dependent relativistic
corrections to the Poisson equation. A comparison with exact linear numerical
analysis indicates that our approximation is a significant improvement over the
standard subhorizon scale independent result on large subhorizon scales. A
comparison with the corresponding results in the Synchronous gauge demonstrates
the validity and consistency of our analysis.Comment: 10 pages, 5 figures. Minor modifications and references added to
match published versio
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Greek ERT: State or Public Service Broadcaster?
The chapter examines the state of public service broadcasting in Greece. While most Southern European public broadcasting systems are to some degree subject to political influence and dependence, in the case of Greece, public broadcaster ERT is, after four decades of deregulation and the break-up of its broadcasting monopoly, still considered by many as ‘state’ rather than a ‘public’ broadcaster. This wide public perception stems from ERT’s one-time role as a mouthpiece of government propaganda. As both radio and TV broadcasting were launched under dictatorships (the late 1930s Metaxas dictatorship and the mid-1960s Colonels rule respectively), they have been regarded as ‘arms of the state.’ Post-dictatorship politics and the restoration of Parliament in 1974 saw the Conservatives (New Democracy) and Socialists (PASOK) dominating the political scene, accusing each other of exercising too much government control over state broadcasting media. Today’s left-wing SYRIZA government also attempts to influence ERT’s output, which is at odds with the digital, deregulated electronic media landscape and consequent abundance of channels. This situation has arisen largely from the political tensions in Greek society since the Second World War. These tensions, combined with the absence of a strong civil society and the market, have made the state an autonomous and dominant factor in Greek society that has to take on additional politico-ideological function. The state plays an active role in the formation of the Greek economy and policy and it is relatively autonomous from society. This makes the system less self-regulatory than countries with developed capitalism, such as northern EU states, Britain or the US. Lack of self-regulation spurs the state to intervene in the politico-ideological sphere and thus diffuse its repressive mechanisms. It is in this context that the chapter explains the rise of power of the media, and the decline of power of journalists and, of course, of ERT itself
Aesthetics of protest: An examination of the photojournalistic approach to protest imagery
Images of protests and demonstrations are crucial to both social movements and protesters who wish to communicate their identity and their messages to wider audiences. However, the photographing of such political events by press photographers is a complex process. The current analysis focuses on questions of aesthetics surrounding issues of visuality regarding protests and demonstrations. Based on empirical data from 17 semi-structured in-depth interviews with Greek photojournalists, this paper examines what is photographed during a protest and how this is affected by the photojournalists’ aesthetic criteria. Drawing on scholarly work on photojournalism (Ritchin and Åker) and photography (Sontag), this article discusses that besides the presumption in the principal of recording reality, photojournalists’ practice is also infused with subjective language and influenced by art photographers’ techniques. Thereupon, the main argument of this paper is that the employment of hybridized photographing practices by photojournalists can have an impact upon their visual decisions with regard to what and how is photographed during a protest. The product of such practices is usually high quality, captivating images with apparent affective qualities
Use of sealants in pancreatic surgery: Critical appraisal of the literature
Background/Aims: Fibrin sealants containing both fibrin and thrombin have been used to control bleeding, reinforce suture lines and enhance tissue healing. However, the literature provides contradictory results. Methods: A systematic literature search was performed to determine the use of fibrin sealants in pancreatic surgery. These articles were then critically appraised according to their methodologies, outcomes and conclusions. Results: Twenty-four studies were found, including 6 controlled randomized trials. Of these, 16 studies were analyzed. Many methodological flaws and lack of consistency in definitions were found, making comparisons between studies difficult if not impossible. Conclusion: Because of the heterogeneity and lack of high-level evidence, the current literature does not allow us any conclusion: neither is there proof that fibrin sealants are of any real utility in pancreatic surgery, nor that they do not work. Further large-scale controlled trials are necessary before concluding that they do or do not provide any advantages in pancreatic surgery. Copyright © 2009 S. Karger AG, Basel
Meta-analysis of endoscopy and surgery versus surgery alone for common bile duct stones with the gallbladder in situ
Background: There is no clear consensus on the better therapeutic
approach (endoscopic versus surgical) to choledocholithiasis. This study
is a meta-analysis of the available evidence.
Methods: A search of the Medline and ISI databases identified 12 studies
that met the inclusion criteria for data extraction. The analysis was
performed using a random-effects model. The outcome was calculated as an
odds ratio (OR) or relative risk (RR) with 95 per cent confidence
intervals (c.i.).
Results: Outcomes of 1357 patients were studied. There was no
significant difference in successful duct clearance (OR 0.85 (95 per
cent c.i. 0.64 to 1.12); P = 0.250), mortality (RR 1.79 (95 per cent
c.i. 0.66 to 4.83); P = 0.250), total morbidity (RR 0.89 (95 per cent
0.71 c.i. to 1.13); P = 0.350), major morbidity (RR 1.34 (95 per cent
c.i. 0.92 to 1.97); P = 0.130) or need for additional procedures (OR
1.37 (95 per cent c.i. 0.82 to 2.29); P = 0.230) between the endoscopic
and surgical groups. There was also no significant difference between
the endoscopic and laparoscopic surgery groups.
Conclusion: Both approaches have similar outcomes, and treatment should
be determined by local resources and expertise
Laparoscopic fenestration for the treatment of patients with severe adult polycystic liver disease
Background: The purpose of this study was to present our experience in
laparoscopic fenestration for patients with severe symptomatic adult
polycystic liver disease (APLD), analyze its feasibility, and evaluate
its immediate and mid-term outcome.
Methods: Between January 2000 and January 2002, 9 patients underwent
laparoscopic fenestration for symptomatic APLD in our laparoendoscopic
unit. All patients had both liver lobes affected with Multiple cysts,
whereas type If disease (present in 8 patients) was not a
contraindication for the procedure. The results were retrospectively
evaluated.
Results: Conversion to laparotomy was required in 1 patient who was
submitted to a second laparoscopic procedure (2 years postoperatively)
after being admitted to our department with sepsis. Complete regression
of symptoms was achieved in 7 of our patients (77.8 %). One death
occurred because of acute renal failure established 5 weeks after the
patient was discharged. During a mean follow-up of 25.8 months, 2
patients presented with recurrence of their symptoms (22.2 %). One of
them was reoperated on; both of them remain symptom free 14 months
postoperatively.
Conclusions: Laparoscopic fenestration appears to be a useful and
effective approach for severe APLD. It is associated with short hospital
stay and a significant symptom-free period. Despite the reported
morbidity, aggressive and meticulous deroofing of as many cysts as
possible can be successfully applied for carefully Selected patients
with type II disease. (C) 2005 Excerpta Medica Inc. All rights reserved
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