Quantum Hamilton-Jacobi analysis of PT symmetric Hamiltonians

We apply the quantum Hamilton-Jacobi formalism, naturally defined in the complex domain, to a number of complex Hamiltonians, characterized by discrete parity and time reversal (PT) symmetries and obtain their eigenvalues and eigenfunctions. Examples of both quasi-exactly and exactly solvable potentials are analyzed and the subtle differences, in the singularity structures of their quantum momentum functions, are pointed out. The role of the PT symmetry in the complex domain is also illustrated.Comment: 11 page

Synthesis, characterization and 11C radiolabeling of aminophenyl benzothiazoles:structural effects on the alkylation of amino group

Several aminophenyl benzothiazoles were prepared with a view to using them as amyloid binding agents for imaging β-amyloid in Alzheimer's disease. These precursors were radiolabeled with 11C-positron-emitting radioisotope using an automated synthesizer and selected radiolabeled compounds were further purified by HPLC. Our results demonstrate that changes in structure have a major influence on the radioactive yield and the ease with which the radiolabel can be introduced. Aminophenyl benzothiazoles with an attached isopropyl group resisted dialkylation perhaps due to steric hindrance caused by this group. Straight chain attachment of methyl, ethyl, butyl, and crotyl groups in the structure decreased the radiochemical yield. Notably, the o-aminophenyl benzothiazole derivatives were difficult to alkylate despite stringent experimental conditions. This reactivity difference is attributed to the hydrogen bonding characteristics of the o-amino group with the nitrogen atom of the thiazole ring

Effect of Surface Oxygen Complexes of Activated Carbon on the Adsorption of 2,4,6- Trinitrophenol

The adsorption isothenns for 2,4,6-trinitrophenol (picric acid) on five samples of coconut-based activated carbons (ACs) with varying. surface area have been studied. The results obtained show thatadsorption depends upon surface area but is not linearly related to it. The adsorption increases on oxidation with ammonium persulphate (NH4)2 S2 08) as well as on degassing at 600 °C. The resultshave been explained on the basis of the existence of surface carbonyl groups, where the 02 of thecarbonyl group interacts with pi electrons of the benzene ring of picric acid

Drowning Among Children 1–4 Years of Age in California, 2017–2021

Background and Objectives: Drowning, the leading cause of unintentional injury death among California children less than five years of age, averaged 49 annual fatalities for the years 2010–2021. The California Pool Safety Act aims to reduce fatalities by requiring safety measures around residential pools. This study was designed to analyze annual fatality rates and drowning incidents in California among children 1–4 years of age from 2017–2021. Methods: We identified fatalities, injury hospitalizations, and emergency department (ED) visits from California state vital statistics death data and state hospital and ED discharge data using the EpiCenter California Injury Data Online website. Results: Over the five-year study period, 4,166 drowning incidents were identified: 234 were fatalities, 846 were hospitalizations, and 3,086 were ED visits. The observed difference in fatality rates from 2017 to 2021 failed to achieve statistical significance (P = 0.88). Location-based analysis of the 234 fatal drowning incidents revealed that pools were the most common injury site, accounting for 65% of the cases. Conclusion: Drowning remains the leading cause of unintentional, injury-related death among California children 1–4 years of age, as the annual rate of fatality over the five-year study period did not decline. While the EpiCenter California Injury Data Online website is excellent for analyzing annual rates of drowning incidents among California residents over time, it is limited in providing insight into modifiable risk factors and event circumstances that can further inform prevention. The development of robust integrated fatal and non-fatal local, state, and national systematic data collection systems could aid in moving the needle in decreasing pool fatalities among young children

Network Physiology reveals relations between network topology and physiological function

The human organism is an integrated network where complex physiologic systems, each with its own regulatory mechanisms, continuously interact, and where failure of one system can trigger a breakdown of the entire network. Identifying and quantifying dynamical networks of diverse systems with different types of interactions is a challenge. Here, we develop a framework to probe interactions among diverse systems, and we identify a physiologic network. We find that each physiologic state is characterized by a specific network structure, demonstrating a robust interplay between network topology and function. Across physiologic states the network undergoes topological transitions associated with fast reorganization of physiologic interactions on time scales of a few minutes, indicating high network flexibility in response to perturbations. The proposed system-wide integrative approach may facilitate the development of a new field, Network Physiology.Comment: 12 pages, 9 figure

Quasi-discretization Of The Electron Continuum Emitted In Collisions Of 0.6 Mev U−¹ Au11+ With Noble Gases

We have measured relative doubly differential cross sections for electron emission in collisions of 0.6 MeV u−1 Au11+ projectile ions with He, Ne and Ar targets for laboratory electron-detection angles between 17\u27 and 80\u27 and electron energies from 100 eV to well above the classical binary encounter region. The authors observe that, independent of the target Zt, the electron spectra display three characteristic peak-line structures whose energies are nearly invariant with observation angle. These structures are attributed to the diffraction of quasi-free target electrons in the potential of the projectile. © 1992 IOP Publishing Ltd

Symbolic Versus Numerical Computation and Visualization of Parameter Regions for Multistationarity of Biological Networks

We investigate models of the mitogenactivated protein kinases (MAPK) network, with the aim of determining where in parameter space there exist multiple positive steady states. We build on recent progress which combines various symbolic computation methods for mixed systems of equalities and inequalities. We demonstrate that those techniques benefit tremendously from a newly implemented graph theoretical symbolic preprocessing method. We compare computation times and quality of results of numerical continuation methods with our symbolic approach before and after the application of our preprocessing.Comment: Accepted into Proc. CASC 201

Enhanced Room Temperature Coefficient of Resistance and Magneto-resistance of Ag-added La0.7Ca0.3-xBaxMnO3 Composites

In this paper we report an enhanced temperature coefficient of resistance (TCR) close to room temperature in La0.7Ca0.3-xBaxMnO3 + Agy (x = 0.10, 0.15 and y = 0.0 to 0.40) (LCBMO+Ag) composite manganites. The observed enhancement of TCR is attributed to the grain growth and opening of new conducting channels in the composites. Ag addition has also been found to enhance intra-granular magneto-resistance. Inter-granular MR, however, is seen to decrease with Ag addition. The enhanced TCR and MR at / near room temperature open up the possibility of the use of such materials as infrared bolometric and magnetic field sensors respectively.Comment: 22 pages of Text + Figs:comments/suggestions([email protected]

Laboratory Measurements of Fe XXIV Line Emission: 3→2 Transitions Near Excitation Threshold

Using the Electron Beam Ion Trap facility at Lawrence Livermore National Laboratory, we have measured relative cross sections for Fe XXIV line emission at electron energies between 0.7 and 3.0 keV. The measurements include line formation by direct electron impact excitation (DE), radiative cascades, resonant excitation (RE), and dielectronic recombination (DR) satellites with captured electrons in n≥5 levels. Good agreement with R-matrix and distorted wave calculations is found. In collisionally ionized plasmas, at temperatures near where the ion abundance peaks (kTe~1.7 keV), the RE contributions are found to be ≲5% of the line emission, while the DR satellites contribute ≲10%. While good agreement with state-of-the-art atomic physics calculations is found, there is less good agreement with existing spectral synthesis codes in common astrophysical use. For the Fe XXIV 3p3/2 → 2s1/2, 3p1/2 → 2s1/2, and 3d5/2 → 2p3/2 transitions, the synthesis code MEKAL underestimates the emissivity in coronal equilibrium by ~20% at temperatures near where the ion abundance peaks. In situations where the ionization balance is not solely determined by the electron temperature, RE and DR satellites may contribute a considerable fraction of the line emission