Developmental integration of the cerebrum and cerebellum in primate model for schizophrenia [abstract]

The cerebellum, via its reciprocal connections with the cerebral cortex, plays an integral role in executive processes that are disrupted in individuals with schizophrenia, including memory, attention, and cognitive flexibility. Interference with neurogenesis during temporally limited spans of fetal development can selectively diminish neuronal populations, and potentially affect connectivity. Here we examine the long-term effects of disrupting neurogenesis during early gestation on the cerebello-thalamo-cerebral circuit in the Rhesus macaque (Macaca mulatta). Magnetic resonance scans were collected at 0.5, 1, 3, and 5 years of age in Rhesus macaques exposed to x-irradiation during early gestation (X; N=5), at a time coinciding with thalamic neurogenesis (E30-41), and in sham-irradiated control animals (C; N=4). We compared cerebellar volume, and correlations between cerebellum and thalamus, and cerebellum and cerebrum at each time point. Results show significant reduction of cerebellar volumes between X and C at each age group (p<0.05) as observed previously in volumes of the thalamus and cerebrum. Further, correlations between cerebellar volume and volume of the other two structures were reduced in X relative to C. These results suggest disruption of cerebellar development and its relationship with the cerebrum following altered neurogenesis. These findings may shed light on the deficits in executive function observed in individuals with schizophrenia, and suggests that changes in the development of cerebello-thalamo-cerebral circuit may be important in the multiple cognitive functions. This study was funded by NIH grants MH071616 and T32MH17104 and the University of Missouri Life Sciences Fellowship

A Search for Stars of Very Low Metal Abundance. VI. Detailed Abundances of 313 Metal-Poor Stars

We present radial velocities, equivalent widths, model atmosphere parameters, and abundances or upper limits for 53 species of 48 elements derived from high resolution optical spectroscopy of 313 metal-poor stars. A majority of these stars were selected from the metal-poor candidates of the HK Survey of Beers, Preston, and Shectman. We derive detailed abundances for 61% of these stars for the first time. Spectra were obtained during a 10-year observing campaign using the Magellan Inamori Kyocera Echelle spectrograph on the Magellan Telescopes at Las Campanas Observatory, the Robert G. Tull Coude Spectrograph on the Harlan J. Smith Telescope at McDonald Observatory, and the High Resolution Spectrograph on the Hobby-Eberly Telescope at McDonald Observatory. We perform a standard LTE abundance analysis using MARCS model atmospheres, and we apply line-by-line statistical corrections to minimize systematic abundance differences arising when different sets of lines are available for analysis. We identify several abundance correlations with effective temperature. A comparison with previous abundance analyses reveals significant differences in stellar parameters, which we investigate in detail. Our metallicities are, on average, lower by approx. 0.25 dex for red giants and approx. 0.04 dex for subgiants. Our sample contains 19 stars with [Fe/H] < -3.5, 84 stars with [Fe/H] < -3.0, and 210 stars with [Fe/H] < -2.5. Detailed abundances are presented here or elsewhere for 91% of the 209 stars with [Fe/H] < -2.5 as estimated from medium resolution spectroscopy by Beers, Preston, and Shectman. We will discuss the interpretation of these abundances in subsequent papers.Comment: Accepted for publication in the Astronomical Journal. 60 pages, 59 figures, 18 tables. Machine-readable versions of the long tables can be found in the ancillary data file

Trigeminal nerve morphology in the American alligator : implications for infering sensory potential in extinct species [abstract]

Among the many adaptations of modern crocodilians, one of the most intriguing is their derived sense of face touch, in which numerous trigeminal nerve-innervated dome pressure receptors speckle the face and mandible and sense vibrations and other mechanical stimuli, directing the animal towards, or away from stimuli. However, the morphological features of this system are not well known, and it remains unclear how aspects of the trigeminal system change during ontogeny and how they scale with other cranial and nervous structures

The effects of a home-based physical activity intervention on cardiorespiratory fitness in breast cancer survivors; a randomised controlled trial

The aim of this current randomised controlled trial was to evaluate the effects of a home-based physical activity (PA) intervention on cardiorespiratory fitness in breast cancer survivors. Thirty-two post-adjuvant therapy breast cancer survivors (age = 52 ± 10 years; BMI = 27.2 ± 4.4 kg∙m2) were randomised to a six-month home-based PA intervention with face-to-face and telephone PA counselling or usual care. Cardiorespiratory fitness and self-reported PA were assessed at baseline and at six-months. Participants had a mean relative V̇O2max of 25.3 ± 4.7 ml∙kg−1∙min−1, which is categorised as “poor” according to age and gender matched normative values. Magnitude-based inference analyses revealed likely at least small beneficial effects (effect sizes ≥.20) on absolute and relative V̇O2 max (d = .44 and .40, respectively), and total and moderate PA (d = .73 and .59, respectively) in the intervention compared to the usual care group. We found no likely beneficial improvements in any other outcome. Our home-based PA intervention led to likely beneficial, albeit modest, increases in cardiorespiratory fitness and self-reported PA in breast cancer survivors. This intervention has the potential for widespread implementation and adoption, which could considerably impact on post-treatment recovery in this population

Modeling Surface and Subsurface Stormflow on Steeply-Sloping Forested Watersheds

A simple conceptual rainfall-runoff model, based on the variable source area concept, was developed for predicting runoff from small, steep-sloped, forested Appalachian watersheds. Tests of the model showed that the predicted and observed daily discharges were in good agreement. The results demonstrate the ability of the model to simulate the flashy hydrologic behavior of these watersheds. Five subsurface flow models were evaluated by application to existing data measured at Coweeta on a reconstructed homogeneous forest soil. The five models were: Nieber \u27s 2-D and 1-D finite element models (based on Richards\u27 equation), the kinematic wave equation, and two simple storage models developed by the authors, the Boussinesq and kinematic storage models. All five models performed reasonably well on this homogeneous soil. The coupled infiltration model had a large effect on the simulation results. The cost of running the computer models and the computer memory requirements increased as their complexity increased. Field soil-water and precipitation measurements were made on a small test plot in Robinson Forest, in Eastern Kentucky. These data were used to calculate runoff during four precipitation events and to test three of the subsurface flow models on a natural watershed. Of the models tested, the simple kinematic storage model performed the best. Flow from the test plot was dominated by macropore flow during storm events, and by flow through the soil matrix during baseflow or recession periods. No surface runoff was observed on the test plot during the period of field observations, except on the saturated near-channel source areas; all runoff was initiated by subsurface flow

Mapping the language-specific cerebrocerebellar network of the human brain through diffusion tensor imaging

Language was arguably a key influence in the evolution of the human brain and the evolution of this behavior in humans was likely associated with gross morphological changes and novel neural networks. My dissertation looked at one such network and verified anatomical connectivity between regions of the cerebellum, thalamus, and frontal lobe active during language using a combination of magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). The results of the DTI analysis and fiber tracking support the hypothesis that there is discrete anatomical connectivity in a language-specific network. The second aim of my dissertation to characterize and quantify this anatomical connectivity in the language-specific functional network between the cerebrum and cerebellum. We analyzed the language-specific cerebrocerebellar network (LSCN) in 59 right-handed neurotypical males through DTI images. My results show the white matter tracts in the LSCN have greater connectivity than that of the white matter in the whole brain, indicating that there is a discrete network between the cerebrum and cerebellum exclusively for language. This anatomical connectivity information about this neural network can now be used in conjunction with behavioral measures in future research on the evolution of the human brain, evolution of language, and pathologies that affect language production