Determining the most recent common ancestor in a finite linear habitat with asymmetric dispersal.

Many species that are birthed in one location and become reproductive in another location can be treated as if in a one-dimensional habitat where dispersal is biased downstream. One example of such is planktonic larvae that disperse in coastal oceans, rivers, and streams. In these habitats, the dynamics of the dispersal are dominated by the movement of offspring in one direction and the distance between parents and offspring in the other direction does not matter.

Parent Perceptions on a Walking School Bus Program Among Low-Income Families: A Qualitative Study.

Background: The walking school bus (WSB) is a promising intervention to increase walking to school and physical activity in school-age children. The aim of this qualitative study was to assess parent perceptions of a WSB program that was part of a randomized controlled trial to inform future programs.

Methods: The authors interviewed 45 parents whose children had participated in a WSB program in the Seattle area, in which third- and fifth-grade students walked to/from school with adult chaperones along a set route.

Systemic Lupus Erythematosus Presenting as Myopericarditis with Acute Heart Failure: A Case Report and Literature Review.

Acutely decompensated dilated cardiomyopathy in a middle-aged patient without the typical risk factor profile presents a clinical dilemma. While cardiomyopathy is a known aspect of systemic lupus erythematosus (SLE), initial clinical presentation as decompensated dilated cardiomyopathy (DCM) is exceedingly rare in the literature. We share the case of a 49-year-old African-American female with no past medical history who presented with overt heart failure of 4 weeks evolution.

Chest Pain Due to Pericardial Effusion as Initial Presenting Feature of Rheumatoid Arthritis: Case Report and Review of the Literature.

Pericardial effusions are not uncommon in rheumatoid arthritis (RA); however, they are rarely the presenting symptom of the disease. We describe a 55-year-old female who presented to the emergency department with complaints of chest pain and dyspnea on exertion. Initial workup revealed a medium-sized pericardial effusion.

Generalized Lymphadenopathy as Presenting Feature of Systemic Lupus Erythematosus: Case Report and Review of the Literature.

Lymphadenopathy could represent a vast spectrum of etiologies including infectious and non-infectious diseases. Besides proper history taking, physical examination, and laboratory investigations, a tissue diagnosis is often necessary to unmask the cause of generalized lymphadenopathy. Here we present a 23-year-old woman who was admitted for diffuse generalized lymphadenopathy, fatigue, malaise, weight loss, nausea, and bilateral lower extremity edema.