Type 1 diabetes mellitus (T1D) is an autoimmune disease that results in deficient production of insulin from pancreatic beta cells. In addition to glycemic control irregularities, T1D can have profound effects on other metabolic processes in the body. Of these, bone, muscle, and adipose tissue metabolism are of interest in the fields of bone density and fracture risk. When combined with a diagnosis of T1D, the lifetime risk of fracture is up to four times higher; however, the relative risk of fracture highest in adulthood. This is of concern as fractures later in life have been shown to have adverse consequences on overall health. Understanding how fat mass and lean mass affect fracture risk in participants with and without T1D has the potential to provide support for accurately predicting and managing this fracture risk. In this cross-sectional analysis of adolescent girls ages 9 -18 with and without T1D, both groups were well matched in most areas, and significant differences between the two groups were seen at body mass index (BMI), BMI Z-score, lean mass index (LMI), LMI Z-score, hemoglobin A1c (HbA1c), and parathyroid hormone (PTH). The calculated predicted force of fall and measured failure load at the distal radius were used to investigate the load-to-strength ratio (LSR). The LSR has the potential to be beneficial in directly assessing fracture risk. From the analysis, it is possible to propose more in-depth studies of the hypothesized positive and negative effects of fat mass and lean mass, respectively on fracture risks.

Bone growth and remodeling are complex phenomena that are influenced by a variety of factors including mechanical stimuli. However, it is still unclear how to identify and quantitatively characterize the mechanical stimuli responsible for bone cell growth. The objective of this study is to design and simulate an experimental apparatus to cyclically apply pressure and shear stresses to bone cells and observe their growth (or lack thereof) as a function of the applied loads.

Short-lived rodents are sensitive to changes in environmental conditions and exhibit annual fluctuations under seasonal environments in northern temperate regions. I analyzed 34 years of monthly live-trapping data on whiteooted mice (Peromyscus leucopus) collected in Carter Woods, Ohio. I used a theoretic-information approach to select the best approximating models and analysis of deviance to infer effects of climate and density on survival of mice. I tested for a cost of reproduction to females and found no difference in survival between reproductive states. Directions and magnitudes of effects of climate and density varied over time. Increased variability in temperature reduced effects of density on survival. I detected an Allee effect and density dependent effects on survival. Long-term trapping data are needed to study temporal effects of climate and density on the demography of rodents. Recruitment had a greater impact on population growth rate than survival

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.