Examining the relationship among measures of global cognition, executive function, and instrumental activities of daily living: can they all just get along?

The subtle nature of executive function deficits makes them difficult to identify in a clinical context and to measure how they impact an individual’s daily life. Clinical neuropsychological assessments alone are often unable to measure how executive deficiencies impact an individual’s daily life. The present study investigated the relationship among clinical screening measures of global cognition, measures of executive function, and instrumental activities of daily living (IADLs). Adults with Parkinson’s disease and neurologically healthy adults completed a battery of assessments including a clinical measure of general functional ability, the Texas Functional Living Scale (TFLS), and a naturalistic shopping task, the University of Tennessee Chattanooga Multiple Errands Test (UTC-MET). TFLS performance was better able to identify functional impairment, while the UTC-MET was able to distinguish inefficient behavior in Parkinson’s disease participants. Findings stress a symbiotic relationship among clinical and naturalistic measures and highlights the important role executive function plays in both

Influence of External pH and Organic Acids on Internal pH and Acid Anion Accumulation in Listeria monocytogenes and Escherichia coli

Listeria monocytogenes and Escherichia coli are both among the most common microbial pathogens that cause foodborne illnesses and death. They both are capable of growing over a wide range of conditions. Organic acids are widely employed in the food industry to control growth of these pathogens to help prevent foodborne illnesses. There is substantial evidence that intracellular accumulation of organic acid anions is a major inhibitor to cell growth, and that many bacteria may combat anion accumulation by lowering their intracellular pH (pHi). In this study, we followed the accumulation of acid anion into the cell pellet and parallel changes in pHi in two human pathogenic strains of L. monocytogenes (N1-227 and R2-499) and in E. coli O157:H7 after exposure to sub-bacteriostatic levels of lactic and acetic acids at mildly acidic pH 6. Cells were exposed to two controls, or to acetic or lactic acid. The accumulation of anions into the cell pellet and pHi was measured after 60 minutes habituation in these treatments.It is noteworthy that our measures of anion accumulation and pHi were independent rather than being confounded as when employing the common practice of calculating intracellular concentration of anions based on difference in internal and external pH, or conversely calculating pHi based on intracellular accumulation of acid anion. All three bacteria accumulated up to 3 times more acetate anion into the cell pellet compared to their external environment. L. monocytogenes accumulated less lactate than acetate anion, and E. coli did not significantly accumulate lactate. The values for anion accumulation into the pellet were much less than expected based on previous reports and predicted by the measured difference in internal and external pH. Exposure of E. coli to organic acids did not induce a change in pHi from its baseline pHi. In contrast, exposure of L. monocytogenes N1-227 and R2-499 to the organic acids induced lowered pHi as compared to baseline in both strains. In summary, Listeria and E. coli were exposed to non-bacteriostatic levels of external organic acids at mildly acidic pH 6. Listeria accumulated more acetate than lactate while mounting a defense against anion accumulation that included lowering its pHi, while E. coli accumulated only acetate and apparently made use of combat mechanisms other than lowering pHi not explored in this study. The methodology employed in these studies was based on independent measures of pHi and intracellular anion accumulation, and the resulting data brings into question the common, but confounding, practice of using intracellular anion accumulation as a measure of pHi, and vice versa

The Wellspring Academy for Christian Leadership : a strategy for developing transformational leaders in the North Carolina Annual Conference

https://place.asburyseminary.edu/ecommonsatsdissertations/1245/thumbnail.jp

Multi-camera Realtime 3D Tracking of Multiple Flying Animals

Automated tracking of animal movement allows analyses that would not otherwise be possible by providing great quantities of data. The additional capability of tracking in realtime - with minimal latency - opens up the experimental possibility of manipulating sensory feedback, thus allowing detailed explorations of the neural basis for control of behavior. Here we describe a new system capable of tracking the position and body orientation of animals such as flies and birds. The system operates with less than 40 msec latency and can track multiple animals simultaneously. To achieve these results, a multi target tracking algorithm was developed based on the Extended Kalman Filter and the Nearest Neighbor Standard Filter data association algorithm. In one implementation, an eleven camera system is capable of tracking three flies simultaneously at 60 frames per second using a gigabit network of nine standard Intel Pentium 4 and Core 2 Duo computers. This manuscript presents the rationale and details of the algorithms employed and shows three implementations of the system. An experiment was performed using the tracking system to measure the effect of visual contrast on the flight speed of Drosophila melanogaster. At low contrasts, speed is more variable and faster on average than at high contrasts. Thus, the system is already a useful tool to study the neurobiology and behavior of freely flying animals. If combined with other techniques, such as `virtual reality'-type computer graphics or genetic manipulation, the tracking system would offer a powerful new way to investigate the biology of flying animals.Comment: pdfTeX using libpoppler 3.141592-1.40.3-2.2 (Web2C 7.5.6), 18 pages with 9 figure

Higher Spin Gravitational Couplings and the Yang--Mills Detour Complex

Gravitational interactions of higher spin fields are generically plagued by inconsistencies. We present a simple framework that couples higher spins to a broad class of gravitational backgrounds (including Ricci flat and Einstein) consistently at the classical level. The model is the simplest example of a Yang--Mills detour complex, which recently has been applied in the mathematical setting of conformal geometry. An analysis of asymptotic scattering states about the trivial field theory vacuum in the simplest version of the theory yields a rich spectrum marred by negative norm excitations. The result is a theory of a physical massless graviton, scalar field, and massive vector along with a degenerate pair of zero norm photon excitations. Coherent states of the unstable sector of the model do have positive norms, but their evolution is no longer unitary and their amplitudes grow with time. The model is of considerable interest for braneworld scenarios and ghost condensation models, and invariant theory.Comment: 19 pages LaTe

Spectral Action for Robertson-Walker metrics

We use the Euler-Maclaurin formula and the Feynman-Kac formula to extend our previous method of computation of the spectral action based on the Poisson summation formula. We show how to compute directly the spectral action for the general case of Robertson-Walker metrics. We check the terms of the expansion up to a_6 against the known universal formulas of Gilkey and compute the expansion up to a_{10} using our direct method

Positive mass theorem for the Paneitz-Branson operator

We prove that under suitable assumptions, the constant term in the Green function of the Paneitz-Branson operator on a compact Riemannian manifold $(M,g)$ is positive unless $(M,g)$ is conformally diffeomophic to the standard sphere. The proof is inspired by the positive mass theorem on spin manifolds by Ammann-Humbert.Comment: 7 page

A note on a gauge-gravity relation and functional determinants

We present a refinement of a recently found gauge-gravity relation between one-loop effective actions: on the gauge side, for a massive charged scalar in 2d dimensions in a constant maximally symmetric electromagnetic field; on the gravity side, for a massive spinor in d-dimensional (Euclidean) anti-de Sitter space. The inclusion of the dimensionally regularized volume of AdS leads to complete mapping within dimensional regularization. In even-dimensional AdS, we get a small correction to the original proposal; whereas in odd-dimensional AdS, the mapping is totally new and subtle, with the `holographic trace anomaly' playing a crucial role.Comment: 6 pages, io

Further functional determinants

Functional determinants for the scalar Laplacian on spherical caps and slices, flat balls, shells and generalised cylinders are evaluated in two, three and four dimensions using conformal techniques. Both Dirichlet and Robin boundary conditions are allowed for. Some effects of non-smooth boundaries are discussed; in particular the 3-hemiball and the 3-hemishell are considered. The edge and vertex contributions to the $C_{3/2}$ coefficient are examined.Comment: 25 p,JyTex,5 figs. on request