No abstract

We study the properties of a finite two-dimensional electron gas system in the Hartree-Fock approximation. We obtain exact analytical expressions for the energy in a finite two-dimensional fully spin-polarized (spinless) system of electrons interacting with a Coulomb potential immersed in a finite square region uniformly filled with a neutralizing positive charge. The difficult two-electron integrals over the finite square domain are reduced to simple compact expressions involving analytic auxiliary functions. We provide results for the potential energy of systems with a finite number of electrons and show how the energy slowly converges towards its thermodynamic limit bulk value

We report a case of diffuse large B-cell breast lymphoma that presented as a palpable breast lump in a male patient evaluated with digital mammography and targeted breast ultrasound (US) but ultimately confirmed by US-guided core needle biopsy. We will discuss the appropriate workup algorithm for a palpable breast lump in a male patient as outlined by the American College of Radiology (ACR) Appropriateness Criteria. While gynecomastia is the most common reason for a new palpable breast lump in a male patient, male breast cancer (including lymphoma and metastasis) can have a similar appearance on imaging. Our goal is to provide clarity on proper radiographic assessment protocols and imaging features of palpable breast masses in men by emphasizing the role of anatomical location and symmetry in distinguishing it from more common causes, such as gynecomastia, in future diagnostic imaging scenarios.

We report a case of a patient with a carotid body tumor with perineural tumor spread along the right superior laryngeal nerve. Perineural spread is most commonly associated with squamous cell, adenoid cystic, and mucoepidermoid carcinoma. To the best of our knowledge, this has not been reported previously with carotid body tumor.