Scattering states of a particle, with position-dependent mass, in a PT{\cal{PT}} symmetric heterojunction

The study of a particle with position-dependent effective mass (pdem), within a double heterojunction is extended into the complex domain --- when the region within the heterojunctions is described by a non Hermitian ${\cal{PT}}$ symmetric potential. After obtaining the exact analytical solutions, the reflection and transmission coefficients are calculated, and plotted as a function of the energy. It is observed that at least two of the characteristic features of non Hermitian ${\cal{PT}}$ symmetric systems --- viz., left / right asymmetry and anomalous behaviour at spectral singularity, are preserved even in the presence of pdem. The possibility of charge conservation is also discussed.Comment: 12 pages, including 6 figures; Journal of Physics A : Math. Theor. (2012

Exact Solutions of the Duffin Kemmer Petiau Equation for the Deformed Hulthen Potential

Using the Nikiforov Uvarov method, an application of the relativistic Duffin Kemmer Petiau equation in the presence of a deformed Hulthen potential is presented for spin zero particles. We derived the first order coupled differential radial equations which enable the energy eigenvalues as well as the full wavefunctions to be evaluated by using of the Nikiforov Uvarov method that can be written in terms of the hypergeometric polynomials.Comment: 8 pages. submitted to Physica Script

Is malignancy associated with pericardial effusion fluid volume or fluid character?

© 2020 Wiley Periodicals LLCIntroduction: Pericardial effusion develops due to different etiologies. The main goals of our study are to understand the etiology and determine whether the amount of pericardial effusion is significant in terms of malignancy. Material and Methods: 142 patients with pericardial effusion, who met the criteria between 1 January 2014 and 1 January 2019, were retrospectively analyzed. All of these patients underwent operation with the subxiphoidal approach. The fluid samples were sent to the microbiology and pathology laboratories for evaluation. Patients underwent follow-up after 1 month. Results: Of the patients included in this study, 72 (61%) of 118 patients were operated on under general anesthesia with a laryngeal mask, and 46 (39%) underwent sedation and local anesthesia. The etiologies found in patients were as follows: effusions resulting from malignancy in 27 (22.9%), idiopathic in 24 (20.3%), cardiac causes (depending on the use of anticoagulants or postoperation) in 22 (18.6%), uremia in 20 (16.9%), infection in 18 (15.3%), and heart failure in 7 patients. The amount of fluid drained from the patients was 661.61 ± 458.34 mL. Out of 27 patients with malignancy, 21 (77.8%) had drainage over 500 mL of effusion fluid, and 6 (22.2%) had drainage under 500 mL. Patients who had positive results tended to have drainage over 500 mL compared with patients who had negative results in terms of malignancy (P =.033). Conclusion: The subxiphoidal approach to pericardial effusion is an easily applicable operation, whether therapeutic or diagnostic. The advantages of the subxiphoidal approach include drainage of all of the fluid and ease of sampling the pericardial fluid. We believe that the amount of fluid drained can lead us to consider malignancy as an etiology