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ABSTRACT There is little information on predator-prey interactions in wind energy landscapes in North America, especially among terrestrial vertebrates. Here, we evaluated how proximity to roads and wind turbines affect mesocarnivore visitation with desert tortoises ( Gopherus agassizii) and their burrows in a wind energy landscape. In 2013, we placed motion-sensor cameras facing the entrances of 46 active desert tortoise burrows in a 5.2-km2 wind energy facility near Palm Springs, California, USA. Cameras recorded images of 35 species of reptiles, mammals, and birds. Counts for 4 species of mesocarnivores at desert tortoise burrows increased closer to dirt roads, and decreased closer to wind turbines. Our results suggest that anthropogenic infrastructure associated with wind energy facilities could influence the general behavior of mammalian predators and their prey. Further investigation of proximate mechanisms that underlie road and wind turbine effects (i.e., ground vibrations, sound emission, and traffic volume) and on wind energy facility spatial designs (i.e., road and wind turbine configuration) could prove useful for better understanding wildlife responses to wind energy development. © 2017 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Hypoxia ischemia (HI) is a recognized risk factor among late-preterm infants, with HI events leading to varied neuropathology and cognitive/behavioral deficits. Studies suggest a sex difference in the incidence of HI and in the severity of subsequent behavioral deficits (with better outcomes in females). Mechanisms of a female advantage remain unknown but could involve sex-specific patterns of compensation to injury. Neuroprotective hypothermia is also used to ameliorate HI damage and attenuate behavioral deficits. Though currently prescribed only for HI in term infants, cooling has potential intrainsult applications to high-risk late-preterm infants as well. To address this important clinical issue, we conducted a study using male and female rats with a postnatal (P) day 7 HI injury induced under normothermic and hypothermic conditions. The current study reports patterns of neuropathology evident in postmortem tissue. Results showed a potent benefit of intrainsult hypothermia that was comparable for both sexes. Findings also show surprisingly different patterns of compensation in the contralateral hemisphere, with increases in hippocampal thickness in HI females contrasting reduced thickness in HI males. Findings provide a framework for future research to compare and contrast mechanisms of neuroprotection and postinjury plasticity in both sexes following a late-preterm HI insult. [ABSTRACT FROM AUTHOR]

R6240 --> 775.11 --> Cleft palate is a common birth defect, requiring interventions that must be timed according to maxillary growth and patients often require multiple procedures to repair an alveolar cleft defect. Mechanical variables, such as pre‐surgical defect shape and size, have been suggested to affect the success of surgical repair, but the biomechanical consequences of these variables are not well understood. We hypothesize that mechanical performance of bony craniofacial structures will vary with cleft morphology. 3D surface models of alveolar cleft defects were created from cone‐bean (CB) CT scans of adolescent and young adult patients (n=36; IRB: 201601711). Surface semilandmarks were used to conduct a cluster analysis, identifying common axes of variation which broadly differentiated between defects that are mediolaterally wider from those that are superoinferiorly taller. The centroid cleft defect shape from Cluster I was selected for preliminary biomechanical analysis. To isolate the mechanical effects of a defect of this shape/size, we used a previously published human cranial finite element model (FEM) as a baseline for model construction and comparison of performance. Patient CBCT was scaled and registered to the FEM and used to reconstruct the defect in the maxilla of the baseline model. Identical boundary conditions (material properties, muscle forces and joint and bite constraints) were applied to the cleft and non‐cleft FE models, to simulate biting on different teeth. Our results reveal notable and unexpected differences in deformation and strain regimes of the cleft and non‐cleft models. Although both models show characteristic regions of elevated strain on the biting‐side, the cleft‐model experiences a marked reduction (50‐90%) in strain on the balancing (non‐biting) side, due to the cleft disrupting the transmission of internal forces across the maxilla and palate from the biting to the balancing side. Importantly, regions that experience diffuse low‐level shear strains in our baseline model drop to nearly undetectable levels in the cleft model. We conclude that it is possible that the reduction of strain below this critical threshold could impede osteogenic mechanical signaling. This has important clinical implications for alveolar cleft defect repair and the development of novel scaffold‐based methods that both survive in vivo and restore functional orofacial load paths. [ABSTRACT FROM AUTHOR]

ABSTRACT Recent biomechanical analyses examining the feeding adaptations of early hominins have yielded results consistent with the hypothesis that hard foods exerted a selection pressure that influenced the evolution of australopith morphology. However, this hypothesis appears inconsistent with recent reconstructions of early hominin diet based on dental microwear and stable isotopes. Thus, it is likely that either the diets of some australopiths included a high proportion of foods these taxa were poorly adapted to consume (i.e., foods that they would not have processed efficiently), or that aspects of what we thought we knew about the functional morphology of teeth must be wrong. Evaluation of these possibilities requires a recognition that analyses based on microwear, isotopes, finite element modeling, and enamel chips and cracks each test different types of hypotheses and allow different types of inferences. Microwear and isotopic analyses are best suited to reconstructing broad dietary patterns, but are limited in their ability to falsify specific hypotheses about morphological adaptation. Conversely, finite element analysis is a tool for evaluating the mechanical basis of form-function relationships, but says little about the frequency with which specific behaviors were performed or the particular types of food that were consumed. Enamel chip and crack analyses are means of both reconstructing diet and examining biomechanics. We suggest that current evidence is consistent with the hypothesis that certain derived australopith traits are adaptations for consuming hard foods, but that australopiths had generalized diets that could include high proportions of foods that were both compliant and tough. Am J Phys Anthropol 151:339-355, 2013.© 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Finite element analysis was used to assess whether the postorbital septum plays a meaningful biomechanical role as a structural support for the circumorbital region in a species of macaque, an anthropoid primate. A finite element model was constructed of a Macaca fascicularis cranium that was subsequently modified to create a second model in which the septum was removed bilaterally. The models were subjected to forces and constraints simulating a molar bite, and resulting strains and displacements were recorded. Strain magnitudes at selected locations on the models were typically lower or unchanged in the model lacking septae, which would seem to be contrary to expectations. However, more broadly, relative to the model containing septae, the model without septae exhibited a mosaic pattern of strain increases and decreases in the circumorbital region. The model lacking septae also exhibited more asymmetric displacements in the orbital region, although not in precisely the manner predicted by prior experimental studies. Overall, the mechanical impact of the postorbital septum is minimal in macaques. These results, when considered along with those of prior experimental studies, suggest that either the postorbital septum in anthropoids did not evolve for mechanical reasons, or, if it did, it no longer plays such a role in extant taxa. [ABSTRACT FROM AUTHOR]