Neuromorphometric characterization with shape functionals

This work presents a procedure to extract morphological information from neuronal cells based on the variation of shape functionals as the cell geometry undergoes a dilation through a wide interval of spatial scales. The targeted shapes are alpha and beta cat retinal ganglion cells, which are characterized by different ranges of dendritic field diameter. Image functionals are expected to act as descriptors of the shape, gathering relevant geometric and topological features of the complex cell form. We present a comparative study of classification performance of additive shape descriptors, namely, Minkowski functionals, and the nonadditive multiscale fractal. We found that the proposed measures perform efficiently the task of identifying the two main classes alpha and beta based solely on scale invariant information, while also providing intraclass morphological assessment

Two photon decay of π0\pi^0 and η\eta at finite temperature and density

A comparative study of the anomalous decays $\pi^0, \eta \to\gamma\gamma$, at finite temperature and at finite density, is performed in the framework of the three--flavor Nambu--Jona-Lasinio. The similarities and differences between both scenarios are discussed. In both cases the lifetimes of these mesons decrease significantly at the critical point, although this might not be sufficient to observe enhancement of these decays in heavy-ion collisions.Comment: 5 pages, 1 figure. Talk given at Strange Quark Matter 2004, Cape Town, South Africa, 15-20 September, 200

Variability in Catheter-Associated Asymptomatic Bacteriuria Rates Among Individual Nurses in Intensive Care Units: An Observational Cross-Sectional Study

Catheter-associated asymptomatic bacteriuria (CAABU) is frequent in intensive care units (ICUs) and contributes to the routine use of antibiotics and to antibiotic-resistant infections. While nurses are responsible for the implementation of CAABU-prevention guidelines, variability in how individual nurses contribute to CAABU-free rates in ICUs has not been previously explored. This study’s objective was to examine the variability in CAABU-free outcomes of individual ICU nurses. This observational cross-sectional study used shift-level nurse-patient data from the electronic health records from two ICUs in a tertiary medical center in the US between July 2015 and June 2016. We included all adult (18+) catheterized patients with no prior CAABU during the hospital encounter and nurses who provided their care. The CAABU-free outcome was defined as a 0/1 indicator identifying shifts where a previously CAABU-free patient remained CAABU-free (absence of a confirmed urine sample) 24–48 hours following end of shift. The analytical approach used Value-Added Modeling and a split-sample design to estimate and validate nurse-level CAABU-free rates while adjusting for patient characteristics, shift, and ICU type. The sample included 94 nurses, 2,150 patients with 256 confirmed CAABU cases, and 21,729 patient shifts. Patients were 55% male, average age was 60 years. CAABU-free rates of individual nurses varied between 94 and 100 per 100 shifts (Wald test: 227.88, P\u3c0.001) and were robust in cross-validation analyses (correlation coefficient: 0.66, P\u3c0.001). Learning and disseminating effective CAABU-avoidance strategies from top-performers throughout the nursing teams could improve quality of care in ICUs

Pseudoscalars Mesons in Hot, Dense Matter

Phase transitions in hot and dense matter and the in--medium behavior of pseudoscalar mesons ($\pi^{\pm}, \pi^0, K^{\pm}, K^0 ,\bar K^0,\eta {and} \eta'$) are investigated, in the framework of the three flavor Nambu--Jona-Lasinio model, including the 't Hooft interaction, which breaks the $U_A(1)$ symmetry. Three different scenarios are considered: zero density and finite temperature, zero temperature and finite density in quark matter with different degrees of strangeness, and finite temperature and density. At T=0, the role of strange valence quarks in the medium is discussed, in connection with the phase transition and the mesonic behavior. It is found that the appearance of strange quarks, above certain densities, leads to meaningful changes in different observables, especially in matter with \beta$--equilibrium. The behavior of mesons in the$T-\rho$ plane is analyzed in connection with possible signatures of restoration of symmetries.Comment: 33 pages, 12 figures, PRC versio

Majority-Vote Model on a Random Lattice

The stationary critical properties of the isotropic majority vote model on random lattices with quenched connectivity disorder are calculated by using Monte Carlo simulations and finite size analysis. The critical exponents $\gamma$ and $\beta$ are found to be different from those of the Ising and majority vote on the square lattice model and the critical noise parameter is found to be $q_{c}=0.117\pm0.005$.Comment: 4 pages, 6 figure

Effective restoration of chiral and axial symmetries at finite temperature and density

The effective restoration of chiral and axial symmetries is investigated within the framework of the SU(3) Nambu-Jona-Lasinio model. The topological susceptibility, modeled from lattice data at finite temperature, is used to extract the temperature dependence of the coupling strength of the anomaly. The study of the scalar and pseudoscalar mixing angles is performed in order to discuss the evolution of the flavor combinations of $q \bar q$ pairs and its consequences for the degeneracy of chiral partners. A similar study at zero temperature and finite density is also realized.Comment: 5 pages, 1 figure. Talk given at Strange Quark Matter 2004, Cape Town, South Africa, 15-20 September, 200

Investigating Alternative Measures of Functional Recovery in Rat Sciatic Nerve Injury

There is a pressing need for advancements in peripheral nerve repair techniques and functional recovery evaluation methods. The rat sciatic nerve injury model is a well examined model for peripheral nerve repair. One measure of functional recovery after nerve damage, the sciatic functional index (SFI), fails in the presence of self-mutilation, toe contracture, and other abnormalities in gait. In this IACUC approved study, the sciatic nerve was severed in four experimental groups (n=5). The nerves were repaired with Arginylglycylaspartic acid-poly(ε-caprolactone) (RGD-PCL) peptide functionalized nanofibers, non-functionalized PCL control nanofibers, an isograft, and a negative control empty conduit. Video walking track analysis allowed for a retrospective analysis with three other evaluation techniques: imbalance coupling (IC), stance factor (SF), and toe out angle (TOA). While these techniques are independent of self-mutilation and toe contracture, walking speed remained as a confounding variable. One way repeated measures ANOVA tests showed no significant difference between treatments or subjects in SFI, SF, or TOA. For SFI, 6 and 12 week trials both saw significant increases over time (p=0.00 for both). A significant difference was found between treatments in IC (p=0.03). Imbalance coupling showed promising Pearson correlation with the current industry standard, SFI (p=0.03). In a regression model, SFI over time had an R-squared value of 94.5%. IC, SF, and TOA had low R-squared values. Future investigation with updated protocol is necessary to confirm the degree of correlation and to evaluate the potential for a new industry standard for evaluating nerve repair

Study od a Slice at +9 to +15 degrees of Declination: I. The Neutral Hydrogen Content of Galaxies in Loose Groups

We examine the H1 content of spiral galaxies in groups by using a catalog of loose groups of galaxies identified in a magnitude limited sample m < 15.7 spanning the range 8 h to 18 h in right ascension and +9 to +15 in declination. The redshift completeness of the galaxy sample is ~95%. No significant effect of H1 depletion is found, although there may be a hint that the earliest type spirals are slightly deficient.Comment: 10 pages, Latex, 3 tables, 5 figures, to appear in the Astronomical Journa