The burden of clostridium difficile infection in patients with liver cirrhosis

Clostridium Difficile Infection (CDI) has registered a dramatically increasing incidence in the general population over the past decades. Nowadays, Clostridium Difficile is the leading cause of hospital-acquired diarrhea in Europe and North America. Liver cirrhosis is the final stage of any chronic liver disease (CLD). The most common causes are chronic hepatitis C or B and viral co-infections, alcohol misuse, and nonalcoholic fatty liver disease (NAFLD). CLD and cirrhosis are listed among the ten leading causes of death in the US. Cirrhosis due to any etiology disrupts the homeostatic role of the liver in the body. Cirrhosis-associated immune dysfunction (CAID) leads to alterations in both inherited and acquired systemic and local liver immunity. CAID is caused by increased systemic inflammation and immunodeficiency and it is responsible for 30% of mortality rates all over the world. Clostridium Difficile infection frequently affects patients suffering from liver cirrhosis because of the high number of prolonged hospitalizations, regular use of antibiotics for the prevention or treatment of SBP, proton pump inhibitor (PPI) use, and an overall immunocompromised state. Clostridium Difficile is a Gram-positive bacterium responsible for the high morbidity and mortality rates in patients with cirrhosis, with an essential increase in a 30-day mortality

Theory of unitarity bounds and low energy form factors

We present a general formalism for deriving bounds on the shape parameters of the weak and electromagnetic form factors using as input correlators calculated from perturbative QCD, and exploiting analyticity and unitarity. The values resulting from the symmetries of QCD at low energies or from lattice calculations at special points inside the analyticity domain can beincluded in an exact way. We write down the general solution of the corresponding Meiman problem for an arbitrary number of interior constraints and the integral equations that allow one to include the phase of the form factor along a part of the unitarity cut. A formalism that includes the phase and some information on the modulus along a part of the cut is also given. For illustration we present constraints on the slope and curvature of the K_l3 scalar form factor and discuss our findings in some detail. The techniques are useful for checking the consistency of various inputs and for controlling the parameterizations of the form factors entering precision predictions in flavor physics.Comment: 11 pages latex using EPJ style files, 5 figures; v2 is version accepted by EPJA in Tools section; sentences and figures improve

One-loop renormalization of general noncommutative Yang-Mills field model coupled to scalar and spinor fields

We study the theory of noncommutative U(N) Yang-Mills field interacting with scalar and spinor fields in the fundamental and the adjoint representations. We include in the action both the terms describing interaction between the gauge and the matter fields and the terms which describe interaction among the matter fields only. Some of these interaction terms have not been considered previously in the context of noncommutative field theory. We find all counterterms for the theory to be finite in the one-loop approximation. It is shown that these counterterms allow to absorb all the divergencies by renormalization of the fields and the coupling constants, so the theory turns out to be multiplicatively renormalizable. In case of 1PI gauge field functions the result may easily be generalized on an arbitrary number of the matter fields. To generalize the results for the other 1PI functions it is necessary for the matter coupling constants to be adapted in the proper way. In some simple cases this generalization for a part of these 1PI functions is considered.Comment: 1+26 pages, figures using axodraw, clarifications adde

Hard Non-commutative Loops Resummation

The non-commutative version of the euclidean $g^2\phi^4$ theory is considered. By using Wilsonian flow equations the ultraviolet renormalizability can be proved to all orders in perturbation theory. On the other hand, the infrared sector cannot be treated perturbatively and requires a resummation of the leading divergencies in the two-point function. This is analogous to what is done in the Hard Thermal Loops resummation of finite temperature field theory. Next-to-leading order corrections to the self-energy are computed, resulting in $O(g^3)$ contributions in the massless case, and $O(g^6\log g^2)$ in the massive one.Comment: 4 pages, 3 figures. The resummation procedure is now discussed also at finite ultraviolet cut-off. Minor changes in abstract and references. Final version to be published in Physical Review Letter

A q-Deformed Schr\"odinger Equation

We found hermitian realizations of the position vector $\vec{r}$, the angular momentum $\vec{\Lambda}$ and the linear momentum $\vec{p}$, all behaving like vectors under the $su_q(2)$ algebra, generated by $L_0$ and $L_\pm$. They are used to introduce a $q$-deformed Schr\" odinger equation. Its solutions for the particular cases of the Coulomb and the harmonic oscillator potentials are given and briefly discussed.Comment: 14 pages, latex, no figure

Alcoholic liver cirrhosis, more than a simple hepatic disease – A brief review of the risk factors associated with alcohol abuse

Liver cirrhosis is a significant public health problem, being an important cause of mortality and morbidity, responsible for approximately 1.8% of the total number of deaths in Europe. Chronic alcohol consumption is the most common cause of liver cirrhosis in developed countries. Europe has the highest level of alcohol consumption among all the global World Health Organisation (WHO) regions. In this paper, we briefly review major factors leading to excessive alcohol consumption in order to draw attention to the fact that alcoholic liver cirrhosis is more than a simple liver disease, and if those risk/causal factors can be prevented, the incidence of this disease could be reduced greatly. Although excessive alcohol consumption is regarded as the cause of alcoholic liver cirrhosis, the etiology is complex, involving multiple factors that act in synchrony, and which, if prevented, could greatly reduce the incidence of this disease. Children of addicts are likely to develop an alcohol-related mental disorder; however, there is no “gene for alcoholism”

Casimir Effect in the Presence of Minimal Lengths

It is expected that the implementation of minimal length in quantum models leads to a consequent lowering of Planck's scale. In this paper, using the quantum model with minimal length of Kempf et al \cite{kempf0}, we examine the effect of the minimal length on the Casimir force between parallel plates.Comment: 10 pages, 2 figure

On the IR/UV mixing and experimental limits on the parameters of canonical noncommutative spacetimes

We investigate some issues that are relevant for the derivation of experimental limits on the parameters of canonical noncommutative spacetimes. By analyzing a simple Wess-Zumino-type model in canonical noncommutative spacetime with soft supersymmetry breaking we explore the implications of ultraviolet supersymmetry on low-energy phenomenology. The fact that new physics in the ultraviolet can modify low-energy predictions affects significantly the derivation of limits on the noncommutativity parameters based on low-energy data. These are, in an appropriate sense here discussed, ``conditional limits''. We also find that some standard techniques for an effective low-energy description of theories with non-locality at short distance scales are only applicable in a regime where theories in canonical noncommutative spacetime lack any predictivity, because of the strong sensitivity to unknown UV physics. It appears useful to combine high-energy data, from astrophysics, with the more readily available low-energy data.Comment: 14 page

Moduli Stabilisation in Heterotic Models with Standard Embedding

In this note we analyse the issue of moduli stabilisation in 4d models obtained from heterotic string compactifications on manifolds with SU(3) structure with standard embedding. In order to deal with tractable models we first integrate out the massive fields. We argue that one can not only integrate out the moduli fields, but along the way one has to truncate also the corresponding matter fields. We show that the effective models obtained in this way do not have satisfactory solutions. We also look for stabilised vacua which take into account the presence of the matter fields. We argue that this also fails due to a no-go theorem for Minkowski vacua in the moduli sector which we prove in the end. The main ingredient for this no-go theorem is the constraint on the fluxes which comes from the Bianchi identity.Comment: 20 pages, LaTeX; references adde

On the UV renormalizability of noncommutative field theories

UV/IR mixing is one of the most important features of noncommutative field theories. As a consequence of this coupling of the UV and IR sectors, the configuration of fields at the zero momentum limit in these theories is a very singular configuration. We show that the renormalization conditions set at a particular momentum configuration with a fixed number of zero momenta, renormalizes the Green's functions for any general momenta only when this configuration has same set of zero momenta. Therefore only when renormalization conditions are set at a point where all the external momenta are nonzero, the quantum theory is renormalizable for all values of nonzero momentum. This arises as a result of different scaling behaviors of Green's functions with respect to the UV cutoff ($\Lambda$) for configurations containing different set of zero momenta. We study this in the noncommutative $\phi^4$ theory and analyse similar results for the Gross-Neveu model at one loop level. We next show this general feature using Wilsonian RG of Polchinski in the globally O(N) symmetric scalar theory and prove the renormalizability of the theory to all orders with an infrared cutoff. In the context of spontaneous symmetry breaking (SSB) in noncommutative scalar theory, it is essential to note the different scaling behaviors of Green's functions with respect to $\Lambda$ for different set of zero momenta configurations. We show that in the broken phase of the theory the Ward identities are satisfied to all orders only when one keeps an infrared regulator by shifting to a nonconstant vacuum.Comment: 29 pages, 8 figures, uses JHEP.cls, references adde