Particle-in-cell simulation study of the scaling of asymmetric magnetic reconnection with in-plane flow shear

We investigate magnetic reconnection in systems simultaneously containing asymmetric (anti-parallel) magnetic fields, asymmetric plasma densities and temperatures, and arbitrary in-plane bulk flow of plasma in the upstream regions. Such configurations are common in the high-latitudes of Earth's magnetopause and in tokamaks. We investigate the convection speed of the X-line, the scaling of the reconnection rate, and the condition for which the flow suppresses reconnection as a function of upstream flow speeds. We use two-dimensional particle-in-cell simulations to capture the mixing of plasma in the outflow regions better than is possible in fluid modeling. We perform simulations with asymmetric magnetic fields, simulations with asymmetric densities, and simulations with magnetopause-like parameters where both are asymmetric. For flow speeds below the predicted cutoff velocity, we find good scaling agreement with the theory presented in Doss et al., J.~Geophys.~Res., 120, 7748 (2015). Applications to planetary magnetospheres, tokamaks, and the solar wind are discussed.Comment: 17 pages, 4 figures, submitted to Physics of Plasma

EVALUATION OF ANTI-HYPERTROPHIC POTENTIAL OF CAMELLIA SINENSIS IN ISOPROTERENOL INDUCED CARDIAC HYPERTROPHY

Objective: Camellia sinensis (C. sinensis family-Theaceae) has potent antioxidant activity used in the treatment of cardiovascular disease. The present study evaluates the cardioprotective (anti-hypertrophic) effect of aqueous extract of C. sinensis in isoproterenol (ISO) induced cardiac hypertrophic rats.Methods: The beneficial effect of the green tea extract was examined by the administration of the aqueous extract of the leaves of C. sinensis (100 mg/kg b.w., oral., 7 d) in ISO (10 mg/kg b.w., subcutaneous.,7 d) induced cardiac hypertrophic rats with reference to the standard drug, losartan (50 mg/kg b.w., oral.,7 d) followed by biochemical estimations of glucose, protein, cholesterol, cardiac marker enzymes namely serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT) and lactate dehydrogenase (LDH) in serum and heart tissues thus collected at the end of 7 d.Results: The biochemical assays revealed significantly (P<0.05) increased glucose, protein, cholesterol, cardiac marker enzymes namely serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT) lactate dehydrogenase (LDH) and significantly (P<0.05) decreased in ISO induced cardiac hypertrophic rats that were reciprocated by the effect of plant extract.Conclusion: Thus, this study showed that the aqueous leaf extract of C. sinensis possesses potent effect against cardiac hypertrophy. This potential is hypothesized to be due to the phytochemical, Catechin present in the plant that requires further isolation and characterization with respect to anti-hypertrophic therapeutics

ANTIDIABETIC ACTIVITY OF BACOLEPIS NERVOSA (WIGHT AND ARN.) DECNE. EX MOQ. EXTRACT ON ALLOXAN INDUCED DIABETIC RATS

Objective: The aim of this study was to investigate the effect of ethanol extracts of stem and leaf of Bacolepis nervosa as antihyperglycemic, anti-hyperlipidemic and antioxidant activity in alloxan-induced diabetic rats. Methods: Diabetes was induced in wistar albino rats by administration of alloxan monohydrate (150 mg/kg). The ethanol extract of B. nervosa leaf and stem at a dose of 150 and 300 mg/kg body weight was administrated at a single dose per day to diabetes-induced rats for a period of 14 d. The effect of ethanol extract of B. nervosa leaf and stem on blood glucose, insulin, urea, creatinine, HbA1C, serum protein, albumin, globulin, serum enzymes, serum lipid profiles, lipid peroxidase (LPO) and antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and reduced glutathione (GSH) were measured in the diabetic rats.Results: The ethanol extract of B. nervosa stem and leaf elicited significant reduction in blood glucose (p<0.001), serum enzymes (SGPT, SGOT, ALP) (p<0.01), lipid parameters (TC, TG, VLDL-LDL, PL) (p<0.01) except HDL-C and significantly increased insulin (p<0.01), HDL-C (p<0.05),, GPx, GSH, SOD and CAT (p<0.05) at the dose of 300 mg/kg when compared with the diabetic-induced control.Conclusion: From the above results, it is concluded that ethanol extracts of B. nervosa leaf and stem possesses significant antihyperglycemic, antihyperlipidemic and antioxidant effect in alloxan induced diabetic rats

Gene expression signatures defining fundamental biological processes in pluripotent, early, and late differentiated embryonic stem cells

Investigating the molecular mechanisms controlling the in vivo developmental program postembryogenesis is challenging and time consuming. However, the developmental program can be partly recapitulated in vitro by the use of cultured embryonic stem cells (ESCs). Similar to the totipotent cells of the inner cell mass, gene expression and morphological changes in cultured ESCs occur hierarchically during their differentiation, with epiblast cells developing first, followed by germ layers and finally somatic cells. Combination of high throughput -omics technologies with murine ESCs offers an alternative approach for studying developmental processes toward organ-specific cell phenotypes. We have made an attempt to understand differentiation networks controlling embryogenesis in vivo using a time kinetic, by identifying molecules defining fundamental biological processes in the pluripotent state as well as in early and the late differentiation stages of ESCs. Our microarray data of the differentiation of the ESCs clearly demonstrate that the most critical early differentiation processes occur at days 2 and 3 of differentiation. Besides monitoring well-annotated markers pertinent to both self-renewal and potency (capacity to differentiate to different cell lineage), we have identified candidate molecules for relevant signaling pathways. These molecules can be further investigated in gain and loss-of-function studies to elucidate their role for pluripotency and differentiation. As an example, siRNA knockdown of MageB16, a gene highly expressed in the pluripotent state, has proven its influence in inducing differentiation when its function is repressed

The directed flow maximum near c_s=0

We investigate the excitation function of quark-gluon plasma formation and of directed in-plane flow of nucleons in the energy range of the BNL-AGS and for the E(Lab)=40AGeV Pb+Pb collisions performed recently at the CERN-SPS. We employ the three-fluid model with dynamical unification of kinetically equilibrated fluid elements. Within our model with first-order phase transition at high density, droplets of QGP coexisting with hadronic matter are produced already at BNL-AGS energies, E(Lab)=10AGeV. A substantial decrease of the isentropic velocity of sound, however, requires higher energies, E(Lab)=40AGeV. We show the effect on the flow of nucleons in the reaction plane. According to our model calculations, kinematic requirements and EoS effects work hand-in-hand at E(Lab)=40AGeV to allow the observation of the dropping velocity of sound via an increase of the directed flow around midrapidity as compared to top BNL-AGS energy.Comment: 10 pages, 4 figures; plot of p(e) at various specific entropies shows why mixed phase is not soft at AGS energ

Maximum Azimuthal Anisotropy of Neutrons from Nb-Nb Collisions at 400 AMeV and the Nuclear Equation of State

We measured the first azimuthal distributions of triple--differential cross sections of neutrons emitted in heavy-ion collisions, and compared their maximum azimuthal anisotropy ratios with Boltzmann--Uehling--Uhlenbeck (BUU) calculations with a momentum-dependent interaction. The BUU calculations agree with the triple- and double-differential cross sections for positive rapidity neutrons emitted at polar angles from 7 to 27 degrees; however, the maximum azimuthal anisotropy ratio for these free neutrons is insensitive to the size of the nuclear incompressibility modulus K characterizing the nuclear matter equation of state.Comment: Typeset using ReVTeX, with 3 ps figs., uuencoded and appende

Flow angle from intermediate mass fragment measurements

Directed sideward flow of light charged particles and intermediate mass fragments was measured in different symmetric reactions at bombarding energies from 90 to 800 AMeV. The flow parameter is found to increase with the charge of the detected fragment up to Z = 3-4 and then turns into saturation for heavier fragments. Guided by simple simulations of an anisotropic expanding thermal source, we show that the value at saturation can provide a good estimate of the flow angle, $\Theta_{flow}$, in the participant region. It is found that $\Theta_{flow}$ depends strongly on the impact parameter. The excitation function of $\Theta_{flow}$ reveals striking deviations from the ideal hydrodynamical scaling. The data exhibit a steep rise of \Theta_{\flow} to a maximum at around 250-400 AMeV, followed by a moderate decrease as the bombarding energy increases further.Comment: 28 pages Revtex, 6 figures (ps files), to appear in Nucl.Phys.

Fragment Flow and the Nuclear Equation of State

We use the Boltzmann-Uehling-Uhlenbeck model with a momentum-dependent nuclear mean field to simulate the dynamical evolution of heavy ion collisions. We re-examine the azimuthal anisotropy observable, proposed as sensitive to the equation of state of nuclear matter. We obtain that this sensitivity is maximal when the azimuthal anisotropy is calculated for nuclear composite fragments, in agreement with some previous calculations. As a test case we concentrate on semi-central $^{197}{\rm Au}\ +\ ^{197}{\rm Au}$ collisions at 400 $A$ MeV.Comment: 12 pages, ReVTeX 3.0. 12 Postscript figures, uuencoded and appende

Directed flow in Au+Au, Xe+CsI and Ni+Ni collisions and the nuclear equation of state

We present new experimental data on directed flow in collisions of Au+Au, Xe+CsI and Ni+Ni at incident energies from 90 to 400A MeV. We study the centrality and system dependence of integral and differential directed flow for particles selected according to charge. All the features of the experimental data are compared with Isospin Quantum Molecular Dynamics (IQMD) model calculations in an attempt to extract information about the nuclear matter equation of state (EoS). We show that the combination of rapidity and transverse momentum analysis of directed flow allow to disentangle various parametrizations in the model. At 400A MeV, a soft EoS with momentum dependent interactions is best suited to explain the experimental data in Au+Au and Xe+CsI, but in case of Ni+Ni the model underpredicts flow for any EoS. At 90A MeV incident beam energy, none of the IQMD parametrizations studied here is able to consistently explain the experimental data.Comment: RevTeX, 20 pages, 30 eps figures, accepted for publication in Phys. Rev. C. Data files available at http://www.gsi.de/~fopiwww/pub