Purpose The authors of this guideline reviewed the urologic trauma literature to guide clinicians in the appropriate methods of evaluation and management of genitourinary injuries. Methods A systematic review of the literature using the MEDLINE® and EMBASE databases (search dates 1/1/90-9/19/12) was conducted to identify peer-reviewed publications relevant to urotrauma. The review yielded an evidence base of 372 studies after application of inclusion/exclusion criteria. These publications were used to inform the statements presented in the guideline as Standards, Recommendations or Options. When sufficient evidence existed, the body of evidence for a particular treatment was assigned a strength rating of A (high), B (moderate) or C (low). In the absence of sufficient evidence, additional information is provided as Clinical Principles and Expert Opinions.

This paper discusses the concepts of fractal geometry in a cellular biological context. It defines the concept of the fractal dimension. D, as a measure of complexity and illustrates the two different general ways of quantitatively measuring D by length-related and mass-related methods. Then, these several Ds are compared and contrasted. A goal of the paper is to find methods other than length-related measures that can distinguish between two objects that have the same D but are structurally different. The mass-related D is shown potentially to be such a measure. The concept of lacunarity, L, is defined and methods of measuring L are illustrated. L is also shown to be a potentially distinguishing measure. Finally, the notion of multifracticality is defined and illustrated to exist in certain individual nerve and glial cells.

The subnivean lairs of the ringed seal (Phoca hispida) were studied in the Amundsen Gulf and Prince Albert Sound areas from 1971 through 1974. The structure of several different types of lairs are described. The existence of a birth-lair complex consisting of several closely adjacent lairs appears likely. The spacial distribution of lairs and lair types found on refrozen leads and in pressure ridges is described. Lairs were more abundant in inshore ice than in offshore ice. The function of subnivean lairs appears to be to provide thermal shelter, especially for neonate seals, and protection from predation by arctic foxes (Alopex lagopus) and polar bears (Ursus maritimus).

Predation of seals by the polar bear, Ursus maritimus, was not significant in the Western Arctic. In the High Central and Eastern Arctic, and along southeastern Baffin Island, bear predation of the subnivean lairs of ringed seals, Phoca hispida, was common. The ice types hunted by bears differed between the High Arctic and southeastern Baffin Island. However, no difference was seen in the proportion of successful kills. There is strong evidence that the bearded seal, Erignathus barbatus, is an important prey species of the polar bear in southeastern Baffin Island. Polar bears mainly kill newborn pups in their birth lairs. The prime breeding habitat of ringed seals located in ice hummock areas is less successfully preyed upon by bears than other ice types. Several factors such as the complexity of birth lairs and possible olfactory confusion might account for this. Seals under 2 years of age are those most frequently killed by bears. Data are presented to show that harvesting these age-classes provides the maximum return of energy to the bear and results in the least harm to the prey population.