Transverse magnetic field influence on wakefield in complex plasmas

We present the results of an investigation of the wakefield around a stationary charged grain in an external magnetic field with non-zero transverse component with respect to the ion flow direction. The impact of the orientation of magnetic field on the wake behavior in streaming complex plasmas is assessed. In contrast to previously reported significant suppression of the wake oscillations due to longitudinal magnetic field applied along flow, in the presence of transverse to flow magnetic field the wakefield exhibits a long range recurrent oscillations. Extensive investigation for a wide range of parameters reveal that in the sonic and supersonic regimes the wake has strong dependence on the direction of the magnetic field and exhibits sensitivity to even a meager deviation of magnetic field from the longitudinal orientation. The tool obtained with the study of impact of transverse component of magnetic field on the wake around grain in streaming ions can be used to potentially maneuver the grain-grain interaction to achieve controlled grain dynamics.Comment: PIC, complex plasma, dust in streaming magnetized ions, monte-carlo, dusty plasma

Testing of bio-rational and synthetic pesticides to manage cabbage aphid (Brevicoryne brassicae L.) in cabbage field at Rampur, Chitwan, Nepal

Cabbage aphid (Brevicoryne brassicae L.) is an important pest of cabbage which reduces the yield and quality of the cabbage head. Farmers haven been using chemical pesticides to manage them but unfortunately these practices are toxic for human health, biodiversity and the environment. The study was conducted to test the efficacy of different bio-rational insecticides along with the chemical insecticide. ‘Green Coronet’ cabbage variety was used and the field experiment was laid out in the experimental farm of Agriculture and Forestry University (AFU), Rampur, Chitwan during the winter season of 2014.  The Experiment was designed in randomized complete block design with having 7 treatments (bio-rational insecticides with chemical and control)  and 3 replications. Plot size was 5.76 m2 (2.4m×2.4m) and spacing of 1 m was maintained between each blocks and plots. Field experiment showed that the highest reduction of cabbage aphid was obtained in Dimethoate (30 EC) treated plot followed by Derisom treated plot. The highest yield of cabbage head was obtained in Dimethoate treated plots (66.47 mt/ha) which was significantly at par with the Derisom (58.79 mt/ ha) treated plots. The yield for other treated plots were 47.60 mt/ha for Margosom, 43.77 mt/ha for Verticillium, 41.63 mt/ ha for Cow urine, 36.77 mt/ ha for Spinosad and control (33.45 mt/ ha) in terms of cabbage head yield. And, at the same time, natural enemies’ population was significantly lower to Dimethoate treated plots compared to bio-rational insecticides. Thus, Derisom (Derris based botanical) might be the best viable alternative in eco-friendly management of cabbage aphid considering cabbage head yield and protection of natural enemies. It was also evident from the research that Margosom (Neem based botanical) was found beneficial not only to conserve natural enemies in the cabbage field but also to minimize cabbage aphid population

Free energy source for flow shear driven instabilities in electron-magnetohydrodynamics

The paper discusses the free energy source for the flow shear driven instability in the context of electron-magnetohydrodynamic (EMHD) system. In EMHD as the electron flow velocity also corresponds to the current in the system, the flow shear driven instability has often been identified both as the fluid Kelvin-Helmholtz (KH)-like mode and as the current gradient driven sausage and kinklike modes. It has been shown here that the free energy source for the flow shear driven instability is the kinetic energy of the electron flow and the instability is essentially a fluid KH mode. The manuscript also provides interpretations for certain characteristic features, such as existence of a threshold wavenumber along the flow direction, the order of magnitude estimation of the growth rate, etc., from physical considerations

Effect of Chloro Substitution in Oxine on Extraction of Uranium(VI)

802-80

Neuroplasticity in hemispheric syndrome: An interesting case report

Functional hemispherectomy is an accepted treatment in hemispherical intractable epilepsy syndromes. We report a patient who had functional hemispherectomy for intractable seizures secondary to right hemispheric cortical dysplasia. Preoperatively, the patient had mild left hemiparesis and functional magnetic resonance imaging (fMRI) showed bilateral motor function lateralization to normal left hemisphere. The patient remains seizure free at 1-year follow-up, with no deterioration of motor power on left side. This report reviews physiology of neural plasticity for motor function lateralization and also reliability of fMRI in determining the functional shift

Non-Maxwellian and magnetic field effects in complex plasma wakes

In a streaming plasma, negatively charged dust particles create complex charge distributions on the downstream side of the particle, which are responsible for attractive forces between the like-charged particles. This wake phenomenon is studied by means of refined linear response theory and molecular dynamics simulations as well as in experiments. Particular attention is paid to non-Maxwellian velocity distributions that are found in the plasma sheath and to situations with strong magnetic fields, which are becoming increasingly important. Non-Maxwellian distributions and strong magnetic fields result in a substantial damping of the oscillatory wake potential. The interaction force in particle pairs is explored with the phase-resolved resonance method, which demonstrates the non-reciprocity of the interparticle forces in unmagnetized and magnetized systems