Background: The first cases of proved COVID-19 in Iran were reported in February 2020 and has since rapidly spread worldwide. We aimed to clarify the clinical significance of hematologic parameters alteration in COVID-19. Methods: Different hematologic parameters were measured in 225 hospitalized COVID-19 patients in a tertiary care university hospital, during the peak of COVID-19 outbreak and their association with duration of hospitalization, ICU admission and especially mortality was analyzed. Results: Among a total of 225 patients, 24.4% did not survive after admission. Lymphopenia and neutrophilia were observed in 52.7% and 21.4% of the patients, respectively. The mean count of neutrophils was significantly higher in non-survived patients (P = .032). Elevated neutrophil-to-lymphocyte ratio (NLR) was significantly associated with mortality (P < .001). Low hemoglobin (Hb) concentration significantly correlated with mortality (P = .004) and ICU admission (P = .04). Platelet (Plt) count was significantly lower in the non-survived patients (P = .023). Non-survivors had significantly lower nadir Hb and Plt counts than survivors (P < .001 in both parameters). Platelet-to-lymphocyte ratio (PLR) also correlated with mortality and was significantly higher in non-survivors (P = .034). Conclusions: Hematologic laboratory parameters have always been a crucial component of diagnostic and therapeutic strategies in infectious disease. Hematologic predictors of a fatal outcome in COVID19 hospitalized patients in our series include elevated NLR and PLR, lower than normal Hb and Plt, elevated d-dimer and prolonged prothrombin time (PT), together with elevated inflammatory indicators in the blood.

We present a model of inflation in which the inflaton field is charged under a triplet of $U(1)$ gauge fields. The model enjoys an internal $O(3)$ symmetry supporting the isotropic FRW solution. With an appropriate coupling between the gauge fields and the inflaton field, the system reaches an attractor regime in which the gauge fields furnish a small constant fraction of the total energy density. We decompose the scalar perturbations into the adiabatic and entropy modes and calculate the contributions of the gauge fields into the curvature perturbations power spectrum. We also calculate the entropy power spectrum and the adiabatic-entropy cross-correlation. In addition to the metric tensor perturbations, there are tensor perturbations associated with the gauge field perturbations that are coupled to metric tensor perturbations. We show that the correction in the primordial gravitational tensor power spectrum induced from the matter tensor perturbation is a sensitive function of the gauge coupling.

We study the false vacuum decay and bubble nucleation in the presence of a cosmic string in de Sitter spacetime. A cosmic string induces a deficit angle in spacetime around itself so the nucleated bubble has the shape of a rugby ball. Working in thin wall approximation and using the junction conditions we study the dynamics of the bubble wall and calculate the Euclidean action. An interesting feature in our analysis is that the tension of the string is screened by the bubble such that an observer inside the bubble measures a different value of the tension than an outside observer. We show that the string can act as a catalyzer in which the nucleation rate is enhanced compared to the Coleman–de Luccia instanton. However, in general, the nucleation rate is not a monotonic function of the difference between the two tensions so in some regions of the parameters space the nucleation rate may be smaller than the Coleman–de Luccia bubble.

We present the effective field theory studies of primordial statistical anisotropies in models of anisotropic inflation. The general action in unitary gauge is presented to calculate the leading interactions between the gauge field fluctuations, the curvature perturbations and the tensor perturbations. The anisotropies in scalar power spectrum and bispectrum are calculated and the dependence of these anisotropies to EFT couplings are presented. In addition, we calculate the statistical anisotropy in tensor power spectrum and the scalar-tensor cross correlation. Our EFT approach incorporates anisotropies generated in models with non-trivial speed for the gauge field fluctuations and sound speed for scalar perturbations such as in DBI inflation.

Allogeneic hematopoietic stem cell transplantation (HSCT) currently is the only available curative option for transfusion-dependent thalassemia. Peripheral blood is a more convenient source for HSCT in comparison with bone marrow. Information about the relative success of transplantation with these 2 graft sources would help physicians and patients choose between them. The aim of this study was to evaluate the pros and cons of using peripheral blood instead of bone marrow as the graft source in thalassemia transplantation. We analyzed the transplant results of 567 transfusion-dependent thalassemia patients who received a transplant between 1998 and 2015 considering their stem cell source as a comparative variable. In multivariate Cox analysis the survival advantage for bone marrow compared with peripheral blood was not significant after adjusting for sex, age, and hepatic fibrosis presence. Rejection incidence was significantly lower in patients who used peripheral blood as their graft source. Acute and chronic graft-versus-host disease were more frequent in peripheral blood transplants, but the difference was not statistically significant. This study shows that peripheral blood could be an alternative stem cell source in patients undergoing allogeneic HSCT for thalassemia.