16 research outputs found
Establishment of the Coulomb law in the layer phase of a pure U(1) lattice gauge theory
In this article we examine the Layer phase of the five dimensional,
anisotropic, Abelian gauge model. Our results are to be compared with the ones
of the 4D U(1) gauge model in an attempt to verify that four dimensional
physics governs the four dimensional layers. The main results are: i) From the
analysis of Wilson loops we verified the behavior, in the layered
phase, for the potential between heavy charges. The renormalized fine structure
constant in the layer phase is found to be equal to that of 4D Coulomb
phase,=. ii) Based on the helicity modulus
analysis we show that the layers are in the Coulomb phase while the transverse
bulk space is in the confining phase. We also calculated the renormalized
coupling and found results compatible with those obtained from the
Coulomb potential. Finally we calculated the potential in the 5D Coulomb phase
and found behavior for the static potential. From
the study of the helicity modulus we have a possible estimate for the five
dimensional renormalized fine structure constant in the region of the critical
value of the bare gauge coupling.Comment: 25 pages, 10 figure
The 4-D Layer Phase as a Gauge Field Localization: Extensive Study of the 5-D Anisotropic U(1) Gauge Model on the Lattice
We study a 4+1 dimensional pure Abelian Gauge model on the lattice with two
anisotropic couplings independent of each other and of the coordinates. A first
exploration of the phase diagram using mean field approximation and monte carlo
techniques has demonstrated the existence of a new phase, the so called Layer
phase, in which the forces in the 4-D subspace are Coulomb-like while in the
transverse direction (fifth dimension) the force is confining. This allows the
possibility of a gauge field localization scheme. In this work the use of
bigger lattice volumes and higher statistics confirms the existence of the
Layer phase and furthermore clarifies the issue of the phase transitions'
order. We show that the Layer phase is separated from the strongly coupled
phase by a weak first order phase transition. Also we provide evidence that the
Layer phase is separated by the five-dimensional Coulomb phase with a second
order phase transition and we give a first estimation of the critical
exponents.Comment: 19 pages, 16 figure
Finite temperature and confinement along the extra dimensions studied on a five-dimensional U(1) lattice gauge model
In this paper we study the properties of the phase diagram of a simple extra
dimensional model on the lattice at finite temperature. We consider the
five-dimensional pure gauge abelian model with anisotropic couplings which at
zero temperature exhibits a new interesting phase, the layer phase. This phase
is characterized by a massless photon living on the four dimensional subspace
and confinement along the extra dimension. We show that, as long as the
temperature takes a non zero value the aforementioned layer phase disappears.
It would be equivalent to assume that at finite temperature the
higher-dimensional lattice model loses any feature of the layered structure due
to the deconfinement which opens up the interactions between the
three-dimensional subspaces at finite temperature.Comment: 24 pages, 10 figure
Exploration of the phase diagram of 5D anisotropic SU(2) gauge theory
In this paper we attempt a non-perturbative study of the five dimensional,
anisotropic SU(2) gauge theory on the lattice using Monte-Carlo techniques. Our
goal is the exploration of the phase diagram, define the various phases and the
critical boundary lines. Three phases appear, two of them are continuations of
the Strong and the Weak coupling phases of pure 4d SU(2) to non-zero coupling
in the fifth transverse direction and they are separated by a
crossover transition, while the third phase is a 5D Coulombic phase. We provide
evidence that the phase transition between the 5D Coulomb phase and the Weak
coupling phase is a second order phase transition. Assuming that this result is
not altered when increasing the lattice volume we give a first estimate of the
associated critical exponents. This opens the possibility for a continuum
effective five dimensional field theory.Comment: 16 pages, 10 figures, essential improvement in the study of the phase
diagra
Measuring the burden of herpes zoster and post herpetic neuralgia within primary care in rural Crete, Greece
<p>Abstract</p> <p>Background</p> <p>Research has indicated that general practitioners (GPs) have good clinical judgment in regards to diagnosing and managing herpes zoster (HZ) within clinical practice in a country with limited resources for primary care and general practice. The objective of the current study was to assess the burden of HZ and post herpetic neuralgia (PHN) within rural general practices in Crete, Greece.</p> <p>Methods</p> <p>The current study took place within a rural setting in Crete, Greece during the period of November 2007 to November 2009 within the catchment area in which the Cretan Rural Practice-based Research Network is operating. In total 19 GP's from 14 health care units in rural Crete were invited to participate, covering a total turnover patient population of approximately 25, 000 subjects. For the purpose of this study an electronic record database was constructed and used as the main tool for monitoring HZ and PHN incidence. Stress related data was also collected with the use of the Short Anxiety Screening Test (SAST).</p> <p>Results</p> <p>The crude incidence rate of HZ was 1.4/1000 patients/year throughout the entire network of health centers and satellite practices, while among satellite practices alone it was calculated at 1.3/1000 patients/year. Additionally, the standardised incidence density within satellite practices was calculated at 1.6/1000 patients/year. In regards to the stress associated with HZ and PHN, the latter were found to have lower levels of anxiety, as assessed through the SAST score (17.4 ± 3.9 vs. 21.1 ± 5.7; <it>p </it>= 0.029).</p> <p>Conclusions</p> <p>The implementation of an electronic surveillance system was feasible so as to measure the burden of HZ and PHN within the rural general practice setting in Crete.</p
Impact of change in high-density lipoprotein cholesterol from baseline on risk for major cardiovascular events
Integration of heparin-binding protein and interleukin-6 in the early prediction of respiratory failure and mortality in pneumonia by SARS-CoV-2 (COVID-19)
Recent publications on the probable role of heparin-binding protein (HBP) as a biomarker in sepsis prompted us to investigate its diagnostic and prognostic performance in severe COVID-19. HBP and IL-6 were measured by immunoassays at admission and on day 7 in 178 patients with pneumonia by SARS-CoV-2. Patients were classified into non-sepsis and sepsis as per the Sepsis-3 definitions and were followed up for the development of severe respiratory failure (SRF) and for outcome. Results were confirmed by multivariate analyses. HBP was significantly higher in patients classified as having sepsis and was negatively associated with the oxygenation ratio and positively associated with creatinine and lactate. Logistic regression analysis evidenced admission HBP more than 18 ng/ml and IL-6 more than 30 pg/ml as independent risk factors for the development of SRP. Their integration prognosticated SRF with respective sensitivity, specificity, positive predictive value, and negative predictive 59.1%, 96.3%, 83.9%, and 87.8%. Cox regression analysis evidenced admission HBP more than 35 ng/ml and IL-6 more than 30 pg/ml as independent risk factors for 28-day mortality. Their integration prognosticated 28-day mortality with respective sensitivity, specificity, positive predictive value, and negative predictive value 69.2%, 92.7%, 42.9%, and 97.5%. HBP remained unchanged over-time course. A prediction score of the disposition of patients with COVID-19 is proposed taking into consideration admission levels of IL-6 and HBP. Using different cut-offs, the score may predict the likelihood for SRF and for 28-day outcome. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature