An exploration of colorectal cancer incidence rates in North Dakota, USA, via structural equation modeling.

Purpose: The state of North Dakota has one of the highest incidence rates for colorectal cancer in the USA. Its high incidence rate, coupled with a large variation in incidence rates among counties within the state, makes North Dakota a "natural laboratory" in which to investigate environmental clues to colorectal cancer. We conducted a hypothesis-generating study to explore potential determinants of colorectal cancer in North Dakota.

Seasonal home ranges and habitat selection of three elk (Cervus elaphus) herds in North Dakota.

Changes in land use have resulted in range shifts of many wildlife species, including those entering novel environments, resulting in the critical need to understand their spatial ecology to inform ecosystem effects and management decisions. Dispersing elk (Cervus elaphus) were colonizing areas of suitable habitat in the Northern Great Plains, USA, resulting in crop depredation complaints in these areas. Although state resource managers had little information on these elk herds, limited evidence suggested temporal movements into Canada.

County level incidence rates of chronic lymphocytic leukemia are associated with residential radon levels.

Aim: We previously reported that incidence rates for chronic lymphocytic leukemia (CLL) among US states are significantly correlated with levels of residential radon (RR). Because these correlations could be influenced by confounding and/or misclassification among large geographic units, we reinvestigated them using smaller geographic units that better reflect exposure and disease at the individual level.

Methods: We examined the relationships between CLL and RR per county in 478 counties with publicly-available data.

Geographic distributions of motor neuron disease mortality and well water use in U.S. counties.

Objective: We recently reported that U.S. mortality rates for motor neuron disease (MND) at the level of the state are associated with well water use.

How does canal taper affect root stresses?

Aim: To examine the effect of specific tapers on root stresses and thus vertical root fracture.

Methodology: The effect of taper on root stresses was calculated during simulated warm vertical compaction of gutta-percha in a straight rooted premolar for three tapers (0.04, 0.