Morphological and Ontogenetic Skin Color Changes in the American Alligator ().

To assess skin color change in alligators, we maintained animals in differently lighted environments and also measured skin colors in an ontogenetic series of wild animals. Juvenile alligators maintained in black enclosures exhibited a gradual lightening of skin color when shifted to white enclosures, and these observed changes were reversible. A histological examination of the skins of alligators maintained in dark tanks showed that the dermis exhibited a dense layer of pigmented cells, while samples from the same animals in light environments exhibited a more diffuse pigmented layer.

The relationship among BSN students' employment, educational, and health-related characteristics and semester grades: A multi-site study.

Background: While many nursing students work during clinical semesters, little is known about employment characteristics and relationships among employment, academic success and other variables.

Purpose: To describe the demographic, educational, and health-related characteristics of clinical nursing students and the relationships among employment, semester grades and other characteristics.

Method: Descriptive, correlational.

Unit Nonresponse in a Population-Based Study of Prostate Cancer.

Low unit response rates can increase bias and compromise study validity. Response rates have continued to fall over the past decade despite all efforts to increase participation. Many factors have been linked to reduced response, yet relatively few studies have employed multivariate approaches to identify characteristics that differentiate respondents from nonrespondents since it is hard to collect information on the latter.

Iron withholding as an innate immune mechanism in the American alligator (Alligator mississippiensis).

Pathogenic microbes require Fe and Zn for growth and proliferation. Upon infection, microbes produce proteins, called sidephores, designed to strip serum divalent metals away from host proteins. Higher vertebrates respond to infection by increasing the expression of proteins that sequester serum iron away from bacteria.