Geometric expansion of the log-partition function of the anisotropic Heisenberg model

We study the asymptotic expansion of the log-partition function of the anisotropic Heisenberg model in a bounded domain as this domain is dilated to infinity. Using the Ginibre's representation of the anisotropic Heisenberg model as a gas of interacting trajectories of a compound Poisson process we find all the non-decreasing terms of this expansion. They are given explicitly in terms of functional integrals. As the main technical tool we use the cluster expansion method.Comment: 38 page

Structural Simulation of Transcatheter Heart Valve in Transcatheter Heart Valve

The durability of transcatheter heart valves (TAV) remains the main disadvantage of transcatheter heart valve implantation (TAVI) for treating aortic valve stenosis. In this study, we assessed the structural mechanics of TAV-in-TAVI using patient-specific modeling. A parametric analysis highlighted that the outcome of TAV-in-TAV depends on the implanted device position and the planned device to be implanted. Contact pressure evinced the impact of different implantation depth and device size on the TAV-in-TAV. This study may bring new insight in the biomechanical performance of TAV to evaluate options for future interventions when the current TAVs experience device failure

Molecular Conformation of Pyridinic Aromatic Esters. II. Electronic Absorption Spectra and Dipole Moments by Semiempirical Methods

The semiempirical MIM method was applied to calculate the UV spectra of nine pyridine-aromatic-ester derivatives (having the general formula R1-COO-R2) assuming a planar geometry. Benzene, pyridine and formic acid were adopted as component systems. The dipole moments of the same compounds were evaluated at the MIM and INDO levels and the equilibrium percentage of the conformers was deduced from experimental and theoretical values. Comparable results were generally obtained. On the whole the results are satisfactory but not sufficient to affirm with certainty if the molecular skeleton is or is not planar

Molecular Conformation of Aza-substituted Benzanilides by Electronic Absorption Spectra and Dipole Moments

The electronic absorption spectra of thirteen pyridine aromatic amides of general formula R1-CO-NH- R2 (Ri, R2 = pyridil or phenyl) were obtained in methanol and dioxane solution. The band assignment is briefly discussed. The dipole moments were measured in dioxane at 25 ± 0.1 °c and compared with values calculated by both the S. H. M. 0. method and vectorial model. The comparison suggests the most probable conformation of derivatives which have the nitrogen either in the ortho or meta position in one or both rings of the molecule

Parametric analysis of transcatheter aortic valve replacement in transcatheter aortic valve replacement: evaluation of coronary flow obstruction

Transcatheter aortic valve replacement (TAVR) is increasingly being considered for use in younger patients having longer life expectancy than those who were initially treated. The TAVR-in-TAVR procedure represents an appealing strategy to treat failed transcatheter heart valves (THV) likely occurring in young patients. However, the permanent displacement of first THV can potentially compromise the coronary access and ultimately inhibit the blood flow circulation. The objective of this study was to use finite-element analysis (FEA) to quantify coronary flow in a patient who underwent TAVR-in-TAVR. A parametric investigation was carried out to determine the impact of both the implantation depth and device size on coronary flow for several deployment configurations. The FEAs consisted of first delivering the SAPIEN 3 Ultra THV and then positioning the Evolut PRO device. Findings indicates that high implantation depth and device undersize of the second THV could significantly reduce coronary flow to 20% of its estimated level before TAVR. Additionally, a positive correlation was observed between coronary flow and the valve-to-coronary distance (R = 0.86 and p = 0.032 for the left coronary artery, and R = 0.93 and p = 0.014 for the right coronary artery). This study demonstrated that computational modeling can provide valuable insights to improve the pre-procedural planning of TAVR-in-TAVR

Biomechanical performance of the Bicaval Transcatheter System for the treatment of severe tricuspid regurgitation

Introduction: Tricuspid regurgitation (TR) is a relatively common valvular disease, which can result from structural abnormalities of any anatomic part of the tricuspid valve. Severe TR is linked to congestive heart failure and hemodynamic impairment, resulting in high mortality when repaired by elective surgery. This study was undertaken to quantify the structural and hemodynamic performance of the novel Transcatheter Bicaval Valves System (TricValve) percutaneously implanted in the superior vena cava (SVC) and inferior vena cava (IVC) of two patients with severe TR and venous congestion. Methods: After developing the SVC and IVC device models, the contact pressure exerted on the vena cava wall was obtained by computational analysis. Both smoothed-particle hydrodynamics (SPH) and computational fluid dynamics were carried out to quantify caval reflux in the right atrium and the pressure field of pre- and post-TricValve scenarios, respectively. Results: Analysis of contact pressure highlighted the main anchoring area of the SVC device occurring near the SVC device belly, while the IVC device exerted pronounced forces in the device’s proximal and distal parts. SPH-related flow velocities revealed the absence of caval reflux, and a decrease in time-averaged pressure was observed near the SVC and IVC after TricValve implantation. Discussion: Findings demonstrated the potential of computational tools for enhancing our understanding of the biomechanical performance of structural tricuspid valve interventions and improving the way we design next-generation transcatheter therapies to treat the tricuspid valve with heterotopic caval valve implantation

Thermodynamic versus Topological Phase Transitions: Cusp in the Kert\'esz Line

We present a study of phase transitions of the Curie--Weiss Potts model at (inverse) temperature $\beta$, in presence of an external field $h$. Both thermodynamic and topological aspects of these transitions are considered. For the first aspect we complement previous results and give an explicit equation of the thermodynamic transition line in the $\beta$--$h$ plane as well as the magnitude of the jump of the magnetization (for $q \geqslant 3)$. The signature of the latter aspect is characterized here by the presence or not of a giant component in the clusters of a Fortuin--Kasteleyn type representation of the model. We give the equation of the Kert\'esz line separating (in the $\beta$--$h$ plane) the two behaviours. As a result, we get that this line exhibits, as soon as $q \geqslant 3$, a very interesting cusp where it separates from the thermodynamic transition line

Humoral immunological parameters in Italian patients with oral lichen planus

Serum humoral immunological parameters were determined in 25 patients with atrophic-erosive forms of oral lichen planus (OLP) (Group 1), in 28 patients with reticular-plaque-like lesions of OLP (Group 2) and in 21 healthy patients without oral lesions (Group 3). Comparing patients affected by atrophic-erosive forms of OLP (Group 1) with normal Controls (Group 3), increased levels of serum IgG approaching the statistical significance were found (Kruskal-Wallis test p = 0.0572). It was also found a significantly higher value of kappa (Kruskal-Wallis test p = 0.0017; Mann-Whitney test with Bonferroni’s correction p < 0.001) and lambda (Kruskal-Wallis test p = 0.0346; Mann-Whitney test with Bonferroni’s correction p = 0.013) light chains in patients with atrophic-erosive OLP (Group 1) as compared with normal controls (Group 3). However these higher levels were probably caused by strong prevalence of chronic liver diseases (40%), in patients with atrophic-erosive variety of OLP. No one of these patients was affected by autoimmune liver disease. No differences were noted between atrophic-erosive OLP (Group 1) and hyperkeratosic OLP (Group 2). This study does not confirm the suggestion that patients with OLP may have a generalized immunologic disorder and it also add some evidences that the role of humoral immunity in the pathogenesis of OLP is probably secondary to the cell-mediated reaction against basal keratinocytes.Les principaux aspects de l’immunologie humorale ont été évalués dans deux groupes de malades porteur d’un lichen plan de la muqueuse buccale, 25 à formes atrophiques-érosives (Groupe 1), 28 à formes en réseaux ou en plaques blanches (Groupe 2), et chez 21 sujets sains. Au terme de cette étude les différences les plus remarquables sont les suivantes: le taux des IgG sériques est nettement plus élevé chez les sujets du Groupe 1 ce qui est presque significatif par rapport au Groupe 3 (p = 0.0577). L’analyse statistique a surtout révélé des différences significatives entre le Groupe 1 et le Groupe 3 (contrôle) en ce qui concerne les taux sériques des chaînes Kappa (Kruskal-Wallis test p = 0.0017; Mann-Whitney test corrigé par Bonferroni p < 0.001 ) et des chaînes Lambda (Kruskal-Wallis test p = 0.0346; Mann-Whitney test corrigé par Bonferroni p = 0.013). Aucune autre différence significative entre les trois groupes n’a été observee. Nous pensons que ces résultats sont probablement dus à la présence d’une hépatopathie chronique non auto-immune qui a été diagnostiquée dans 40% des cas du Groupe 1. Cette étude ne confirme donc pas la thèse selon laquelle les sujets atteints de lichen plan buccal pourraient avoir une défaillance de l’immunité humorale. Elle nous permet de penser que le rôle de cette dernière dans la pathogénèse de la maladie est probablement secondaire à la réaction cellulaire dirigée contre les kératinocytes

Phenotypic analysis of peripheral blood cell immunity in Italian patients with different varieties of oral lichen planus

Quantitative analysis of peripheral blood lymphocytes was carried out in 25 patients with atrophic-erosive type of oral lichen planus (OLP) (Group 1), in 28 patients with reticular-plaque like lesions of OLP (Group 2) and in 21 healthy patients (Group 3) by using flow cytometry. CD4 + subsets decreased significantly in patients with reticular-plaque like varieties when compared with healthy patients (Group 3) (One way analysis of variance p = 0.039; t-test with Bonferroni correction p< 0.05). Moreover, in patients with hyperkeratosic forms of OLP (Group 2) CD8 + cell populations were significantly higher than in controls (Group 3) (Kruskal-Wallis test p = 0.035; Mann-Whitney test with Bonferroni’s correction p< 0.0001) and consequently CD4/CD8 ratio was significantly lower in patients with reticular-plaque like lesions than in controls (Kruskal-Wallis test p = 0.01; Mann-Whitney test with Bonferroni’s correction p = 0.013). No statistical differences between patients of Group 1 (atrophic-erosive OLP) and the other two Groups (hyperkeratosic OLP and healthy controls) were detected. 40% of the patients of Group 1 were affected by chronic hepatopathies, most of which were related to hepatitis C virus (HCV), but the data were not substantially modified after adjustment for the patients with chronic liver disease HCV positive. There is no clear evidence that these results indicate the existence of a different pathogenetic mechanism between erosive-atrophic and hyperkeratosic types of OLP. On the other hand, these results and the previously reported immunohistochemical findings suggest that quantitative alterations of peripheral blood lymphocytes in hyperkeratosic varieties of OLP could represent a shift of CD4 + cells from the vascular to the oral mucosa compartment.Les lymphocytes du sang périphérique ont été évalués par cytométrie de flux dans deux groupes de malades porteurs d’un lichen plan de la muqueuse buccale: 25 à forme atrophique-érosive (Groupe 1), 28 à forme en réseaux ou en plaques blanches (Groupe 2), et chez 21 sujets sains (Groupe 3). Au terme de cette étude les différences les plus remarquables ont été les suivantes: diminution de la fraction CD4 + et une augmentation de la fraction CD8 + dans le Groupe 2 (réseaux et plaques blanches) comparés au Groupe 3 (contrôle), la différence est statistiquement significative (One ways analysis of variance p = 0.039, t test corrigé par Bonferroni p<0.05 pour CD4 + et Kruskal-Wallis test p = 0.035, Mann-Whitney test corrigé par Bonferroni p< 0.001 pour CD8 + ) par conséquent le rapport CD4/CD8 du Groupe 2 a été significativement plus bas par rapport au Groupe 3 (Kruskal-Wallis test p = 0.014; Mann-Whitney test corrigé par Bonferroni p = 0.013). Aucune autre différence significative entre les trois groupes n’a été observée, en particulier avec le Groupe 1 (formes atrophiques-érosives) dont il faut signaler que le 40% des sujets sont porteurs d’une hépatopathie chronique souvent due au virus de l’hépatite C. En conclusion la différence des résultats entre les groupes 1 et 2 ne permet pas d’affirmer l’existence d’une pathogénie différente entre les formes atrophiques-érosives et les formes en réseaux ou en plaques, elle est en accord avec les précédentes études en histo-immunochimie. Il est possible que la diminution des lymphocytes CD4 + soit secondaire au déplacement de cette population cellulaire du compartement vasculaire de la muqueuse affectée par le lichen plan.