Shocks in the asymmetric exclusion process with internal degree of freedom

We determine all families of Markovian three-states lattice gases with pair interaction and a single local conservation law. One such family of models is an asymmetric exclusion process where particles exist in two different nonconserved states. We derive conditions on the transition rates between the two states such that the shock has a particularly simple structure with minimal intrinsic shock width and random walk dynamics. We calculate the drift velocity and diffusion coefficient of the shock.Comment: 26 pages, 1 figur

An Empirical Relation Between The Large-Scale Magnetic Field And The Dynamical Mass In Galaxies

The origin and evolution of cosmic magnetic fields as well as the influence of the magnetic fields on the evolution of galaxies are unknown. Though not without challenges, the dynamo theory can explain the large-scale coherent magnetic fields which govern galaxies, but observational evidence for the theory is so far very scarce. Putting together the available data of non-interacting, non-cluster galaxies with known large-scale magnetic fields, we find a tight correlation between the integrated polarized flux density, S(PI), and the rotation speed, v(rot), of galaxies. This leads to an almost linear correlation between the large-scale magnetic field B and v(rot), assuming that the number of cosmic ray electrons is proportional to the star formation rate, and a super-linear correlation assuming equipartition between magnetic fields and cosmic rays. This correlation cannot be attributed to an active linear alpha-Omega dynamo, as no correlation holds with global shear or angular speed. It indicates instead a coupling between the large-scale magnetic field and the dynamical mass of the galaxies, B ~ M^(0.25-0.4). Hence, faster rotating and/or more massive galaxies have stronger large-scale magnetic fields. The observed B-v(rot) correlation shows that the anisotropic turbulent magnetic field dominates B in fast rotating galaxies as the turbulent magnetic field, coupled with gas, is enhanced and ordered due to the strong gas compression and/or local shear in these systems. This study supports an stationary condition for the large-scale magnetic field as long as the dynamical mass of galaxies is constant.Comment: 23 pages, 4 figures, accepted for publication in the Astrophysical Journal Letter

The Magnetized Disk-Halo Transition Region of M51

An excellent laboratory for studying large scale magnetic fields is the grand de- sign face-on spiral galaxy M51. Due to wavelength-dependent Faraday depolarization, linearly polarized synchrotron emission at different radio frequencies gives a picture of the galaxy at different depths: Observations at L-band (1-2 GHz) probe the halo region while at C- and X- band (4-8 GHz) the linearly polarized emission probe the disk region of M51. We present new observations of M51 using the Karl G. Jansky Very Large Array (VLA) at S-band (2-4 GHz), where previously no polarization observations existed, to shed new light on the transition region between the disk and the halo. We discuss a model of the depolarization of synchrotron radiation in a multilayer magneto-ionic medium and compare the model predictions to the multi-frequency polarization data of M51 between 1-8GHz. The new S-band data are essential to distinguish between different models. Our study shows that the initial model parameters, i.e. the total reg- ular and turbulent magnetic field strengths in the disk and halo of M51, need to be adjusted to successfully fit the models to the data.Comment: 4 Pages, 3 Figures, Conference Proceeding to IAU Focus Meeting 8: New Insights in Extragalactic Magnetic Field

Induced Nucleon Polarization and Meson-Exchange Currents in (e,e'p) Reactions

Nucleon recoil polarization observables in $(e,e'\vec{p})$ reactions are investigated using a semi-relativistic distorted-wave model which includes one- and two-body currents with relativistic corrections. Results for the induced polarization asymmetry are shown for closed-shell nuclei and a comparison with available experimental data for $^{12}$C is provided. A careful analysis of meson exchange currents shows that they may affect significantly the induced polarization for high missing momentum.Comment: 7 pages, 9 figures. Revised version with small changes, new curve in Fig. 3. To be published in PR

CLINICAL EVALUATION OF EPIDURAL ADMINISTRATION OF MORPHINE, FENTANYL, METHADONE, LIDOCAINE AND LIDOCAINE WITH EPINEPHRINE IN CATTLE

The purpose of this study was to determine the analgesic efficacy and clinical effects of morphine, fentanyl, methadone, lidocaine, lidocaine with epinephrine and saline (control) when injected epidurally into the caudal epidural space in cattle. Epidural analgesia was achieved in five cattle on five successive occasions at weekly intervals. Analgesia was defined as a lack of response to hemostat pressure and pinprick in the skin of the perineal area and ventral aspect of the tail. The results demonstrated that while epidural lidocaine and lidocaine with epinephrine decreased the response to hemostat and pinprick compared to control, there was no reduction in response after the administration of morphine, methadone or fentanyl. Heart rate, pulse and respiratory rates were not significantly altered by any of the drugs. Neither did the drugs produce any change in the electrocardiogram (ECG) of the animals

Comparison of chilling and heat requirement in some peach and apricot cultivars

Bud Dormancy in deciduous fruit trees of the temperate zones is a phase ofdevelopment that occurs annually and enables trees to survive cold winters. Chilling andheat requirements for breaking dormancy and flowering were studied in five peach (Kosary,Haj Kazemi, Anjiry Asali, Anjiry Zafarany, and Zoud Ras) and four apricot (asgarabad,shamlo, shakarpare, tabarze ghermez) cultivars. Various models (two chilling hour models,the <7C and 0-7C models, and two chilling unit models, the Utah and Low Chill) were usedto measure the accumulation of chilling requirement. The heat requirements were calculatedas the growing degree hours (GDH) accumulated from breaking of dormancy to the F50 (50%of opened flowers). The cultivars studied showed a range of chilling requirements (chillunits, CU), between 746 to 868 CU for peach and 652-826 CU for apricot. The heatrequirements for peaches and apricots were between (4099 to 4543GDH) and (2987 to3465GDH) respectively. Apricot cultivars with lower chilling and heat requirements showedearlier flowering dates. Thus apricot cultivars bloomed between 15 and 16 day before peachcultivars and Heat requirements were found to be more important for regulation offlowering time than were chilling requirement in our climatic condition