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To describe the rare presentation, imaging and histological findings, and treatments in patients with IgG4-related disease (IgG4-RD) and diagnostic pitfalls and difficulties.Cases of sinonasal IgG4-RD were retrieved, and clinicopathological features were reviewed.Seven cases of sinonasal IgG4-RD were identified over an 11-year period, including four males and three females, with an age range of 19-66 years (median 58 years). Patients presented with symptoms related to the mass effect of the lesions or the destructive nature of the disease including fullness, swelling, obstruction, and pain. Serum IgG and IgG4 levels, IgG/IgG4 ratios, storiform fibrosis, obliterative phlebitis, and plasma cell infiltration were seen in varying proportions. Bony erosion and tissue inflammation were present in some cases.Sinonasal IgG4-RD is exceedingly rare among other IgG4-RD and varied in its clinical presentation thus posing as a clinically difficult disease to diagnosis. Proper clinical, pathological, and immunohistopathological analysis is required for accurate diagnosis. Such disease should be considered in all cases of similar presentation to those in this study.Level of Evidence: 4.

We basis our initial analysis of the arrow of time on a relationship between the time evolution operator of quantum system and the time-independent density operator which describes the equilibrium state of a many-particle system at temperature $T$. We highlight through this analysis the identification of the imaginary temporal component of the branch-cut complex cosmic form factor with the direction in which the time-parameter flows globally, or the arrow of time. As a novelty, in this work we calculate the number of branches in the branch-cut universe to achieve causality involving the global time of evolution of the universe and the local time of travel of the light around each Hubble horizon. The preliminary result obtained is comparable to 60 e-folds of contraction in the FLRW cosmic scale factor $a(t) $ to overcome causality achieved in the bouncing model.

In this contribution we address the implications of the Bekenstein Criterion in the branch-cut cosmology. The impossibility of packaging energy and entropy according to the Bekenstein Criterion in a finite size makes the transition phase of the branch-cut cosmology very peculiar, imposing a topological leap between the contraction and expansion phases of the primordial universe or a transition region similar to a wormhole, with space-time shaping itself topologically in the format of a helix-format around a branch point. Singularity means that there is no way for space-time to begin smoothly. The branch-cut cosmology alternatively proposes a non-temporal beginning at all, a pure space configuration, through a Wick rotation which replaces the imaginary time component by the temperature, the cosmological time.

In this article we follow a previously developed theoretical approach, based in the tools of the singular semi-Riemannian geometry, to push the limits of time beyond the primordial spacetime singularity. By complexifying the Friedmann-Lemaitre-Robertson-Walker (FLRW) metric and Friedmann's equations we model a branch cut universe, in which the cosmic FLRW metric scale factor is analytically continued to the complex plane, and becomes equivalent from a conceptual point of view of describing a hypothetical general metric of maximally symmetric and homogeneous superposed multiple universes.

In this contribution we identify two scenarios for the evolutionary branch cut universe. In the first scenario, the universe evolves continuously from the negative complex cosmological time sector, prior to a primordial singularity, to the positive one, circumventing continuously a branch cut, and no primordial singularity occurs in the imaginary sector, only branch points. In the second scenario, the branch cut and branch point disappear after the realisation of the imaginary component of the complex time by means of a Wick rotation, which is replaced by the thermal time. In the second scenario, the universe has its origin in the Big Bang, but the model contemplates simultaneously a mirrored parallel evolutionary universe going backwards in the cosmological thermal time negative sector. A quantum formulation based on the WDW equation is sketched and preliminary conclusions are drawn.

The cooling of neutron stars (hereafter NS) has the potential to reveal important features of superdense matter. Their surface temperatures are known for a fair sample of NS with ages $\leq 10^{6} \, {\it{yr}}$, and with a few exceptions, can be accommodated by standard cooling mechanisms (neutrino+photon emission without internal heating). However, for the older objects it is necessary to consider some internal heating to explain surface temperatures higher than expected. We revisit in this paper the kinetic heating by fermionic dark matter, rotochemical heating and magnetic field decay. We found that NS slightly older than $\sim 10^{6} \, {\it{yr}}$ can be explained by them, but the older ``black widow'' systems are much hotter than the values predicted by these three mechanisms, pointing towards a yet unknown heating factor for old NS., Accepted for publication in IJMPD, 25 pages, 10 figures, 3 tables

The prediction of properties of the low energy portion of the hadronic spectrum is a challenging task which, up to day, is still tentatively given due to the non-perturbative nature of QCD at low energies. In this paper we are exploring the validity of the SO(4) scheme, as representative of the fundamental QCD structure of meson-like states in the region below 2.5 GeV. We have focussed the attention in the calculation of the energy and width of states of various spin, isospin and parities. The theoretical results are compared, sistematically, to the available experimental information., 16 pages, 11 figures, 9 tables, 36 references

The effects of a minimal length are investigated within an algebraically extended theory of General Relativity (GR). Former attempts, to include a minimal length in GR are first resumed, with a conformal factor of the metric as a consequence. Effective potentials for various black hole masses (as ratios to the minimal length) are deduced. It is found that the existence of a minimal length has, for a small mass black hole, important effects on the effective potential near the event horizon, creating barriers which inhibit that particles can pass the event horizon. Further, a new limit for the minimal mass of a black hole is derive, Comment: 23 pages, 11 figures

An approximate but straightforward projection method to molecular many $\ensuremath{\alpha}$-particle states is proposed and the overlap to the shell model space is determined. This construction of the space poses an alternative to other techniques which use a more general, larger subset of the shell model space and/or use involved numerical methods. The resulting space is in accordance with the shell model, but still contains states which are not completely symmetric under permutations of the $\ensuremath{\alpha}$ particles, which is one reason to call the construction approximate. A new contribution is the construction of the six- and seven-$\ensuremath{\alpha}$-particle spaces. The errors of the method propagate toward larger numbers of $\ensuremath{\alpha}$- and larger shell excitations. In order to show the practicality of the construction proposed, the obtained spaces are applied, within an algebraic cluster model, to $^{20}\mathrm{Ne}, ^{24}\mathrm{Mg}$, and $^{28}\mathrm{Si}$, each treated as a many-$\ensuremath{\alpha}$-particle system. Former results on $^{12}\mathrm{C}$ and $^{16}\mathrm{O}$ are re-examined.

An extension of the Semimicroscopic Algebraic Cluster Model (SACM) is proposed, based on the pseudo-SU(3) model ( $$\widetilde{SU}(3)$$ ). The Hamiltonian of the model is presented and a procedure of constructing the model space. Because a huge number of SU(3) irreducible representations (irrep) appear, one has to be careful in designing a practical, consistent path to reduce the Hilbert space. The concept of forbiddenness, taking into account excitations of the clusters, is introduced and applied. The applications are to two systems with a low forbiddenness, namely to $$^{236}$$ U $$\rightarrow $$ $$^{210}$$ Pb + $$^{26}$$ Ne and $$^{224}$$ Ra $$\rightarrow $$ $$^{210}$$ Pb + $$^{14}$$ C, and to $$^{236}$$ U $$\rightarrow $$ $$^{146}$$ Xe + $$^{90}$$ Sr, which appears in the fission of $$^{236}U$$ , which requires a large forbiddenness. Energies and electromagnetic transitions are calculated.

Introduction: To date, clear cell renal carcinoma (Grawitz tumour) remains the most frequent malignant tumour of the kidney in adults. It metastasises in more than 25% of cases, most frequently to the bones (osteolytic metastases), lungs, brain, liver, adrenal glands and the contralateral kidney. Metastases to the pancreas are rare and represent 1–4% of all malignant tumours of the pancreas. Methods: This is a retrospective analysis of patients who were operated at the Department of Surgery in Pilsen between 2010 and 2018 for histologically verified metastasis of clear cell carcinoma (Grawitz tumour) to the pancreas. Results: We operated 12 patients (8 men and 4 women). The metastases appeared on average 8 years and 8 months following the primary urological surgery. The mean age of the male patients was 66.5 years and that of the female patients was 67.4 years. In our sample, the diagnostic specificity of the CT scan was 50%, the diagnostic specificity of endoscopic ultrasound (EUS) was 75% and subsequen EUS-guided fine needle aspiration biopsy performed in 100% of cases yielded a specificity of 75%. Resectability was 92%. The average length of hospitalisation was 11.5 days. Post-operative complications according to Clavien-Dindo were grade 1 in 66%, grade 2 in 1.25% and grade 5 in 8.3% of the cases. The 30-day post-operative mortality was 8.3% (one patient). Conclusion: Clear cell renal carcinoma metastases to the pancreas are very rare. However, if radically removed, the patient has a good prognosis with regards to long-term survival.

The catastrophe theory is applied to a nuclear cluster model and an effective model for QCD at low energy. The study of quantum phase transitions in the cluster model was considered in an earlier publication, but restricted to spherical clusters and on a semi-classical level. In the present contribution, we include the case of deformed clusters and determine the spectrum numerically as a function of an interaction parameter, where signatures of a quantum phase transition can be seen. It is shown that in this more complicated case, with deformation of the clusters, the catastrophe theory can be applied with some interesting consequences. A further example of a many-body problem is considered, namely an effective model of QCD, which is able to describe the low energy hadron spectrum and, when temperature is introduced, even ratios of particle-antiparticle productions. The catastrophe theory is able to provide useful information on the phase transition from a perturbative to a non-perturbative vacuum. This contributions shows the universal usefulness of catastrophe theory, while more examples of applications to different fields are mentioned in the Introduction., Comment: 25 pages, 10 figures