Genetic factors such as decreased genetic
diversity and increased homozygosity can have detrimental
effects on rare species, and may ultimately limit potential
adaptation and exacerbate population declines. The Gulf
and Atlantic Coastal Plain physiographic region has the
second highest level of endemism in the continental USA,
but habitat fragmentation and...
We study a class M of cyclically presented groups that includes both finite and infinite groups and is defined by a certain combinatorial condition on the defining relations. This class includes many finite metacyclic generalized Fibonacci groups that have been previously identified in the literature. By analyzing their shift extensions...
We study a class of two-generator two-relator groups, denoted J[subscript n](m, k), that arise in the study of relative asphericity as groups satisfying a transitional curvature condition. Particular instances of these groups occur in the literature as finite groups of intriguing orders. Here we find infinite families of non-elementary virtually...
A group defined by a finite presentation with cyclic symmetry admits a shift automorphism that is periodic and word-length preserving. It is shown that if the presentation is combinatorially aspherical and orientable, in the sense that no relator is a cyclic permutation of the inverse of any of its shifts,...
Changes in dietary selenium and selenoprotein status may influence both anti- and pro-cancer pathways, making the outcome of interventions different from one study to another. To characterize such outcomes in a defined setting, we undertook a controlled hepatocarcinogenesis study involving varying levels of dietary selenium and altered selenoprotein status using...
A key constraint faced by consumers is achieving a positive energy balance in the face of temporal variation in foraging opportunities. Recent work has shown that spatial heterogeneity in resource phenology can buffer mobile consumers from this constraint by allowing them to track changes in resource availability across space. For...
A time history of the calibration coefficients for channels 1 and 2 of the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-12 and NOAA-15 spacecraft is presented. The history is based on reflectances observed for the interior zones of the Antarctic and Greenland ice sheets previously obtained with the...
Visible and near infrared reflectances from NOAA-14 Advanced Very High Resolution Radiometer (AVHRR) daytime passes are used to derive optical depths at 0.55 μm, an index of aerosol type, continental or marine, and the direct effect of the aerosol on the top of the atmosphere and surface solar radiative fluxes...
The amount and type of carbon (C) in a forest soil reflects the past balance between C accumulation and loss. In an old-growth forest soil, C is thought to be in dynamic equilibrium between accumulations and losses. Disturbance upsets this equilibrium by altering the microclimate, the amount and type of...
