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Weibel-type instability can self-generate and amplify magnetic fields in both space and laboratory plasmas with temperature anisotropy. The electron Weibel instability has generally proven more challenging to measure than its ion counterpart owing to the much smaller inertia of electrons, resulting in a faster growth rate and smaller characteristic wavelength. Here, we have probed the evolution of the two-dimensional distribution of the magnetic field components and the current density due to electron Weibel instability, in $\rm CO_2$-ionized hydrogen gas (plasma) with picosecond resolution using a relativistic electron beam. We find that the wavenumber spectra of the magnetic fields are initially broad but eventually shrink to a narrow spectrum representing the dominant quasi-single mode. The measured $k$-resolved growth rates of the instability validate kinetic theory. Concurrently, self-organization of microscopic plasma currents is observed to amplify the current modulation magnitude that converts up to $\sim 1\%$ of the plasma thermal energy into magnetic energy., 24 pages, 4 figures

Background: There are different methods of Vatsanabha shodhana but it is not mentioned in literature that which method should be used in preparation of Tribhuvankirti rasa which will make the drug safer. Objectives: To acquire knowledge regarding toxic principle in self prepared and market sample of Tribhuvankirti Rasa with respect to different shodhana methods of Vatsanabha and to develop a method of testing toxic principle in the formulation. Material and methods: Three samples were prepared out of which two samples were prepared using different shodhana media and one sample was prepared using impure ingredients and three samples of Tribhuvankirti Rasa were purchased from market. Physicochemical and phytochemical analysis of the final product was conducted and the observations were compared among six samples. Results: HPLC graphs indicate that the numbers of peaks are increased in the sample prepared with Godugdda shodhita Vatsanabha and all the market samples in comparison with Ashodhita and Gomutra shodhita samples of Tribhuvankirti Rasa. All samples contain alkaloids, however after purification there was decrease in the concentration of detected alkaloid. Conclusion: The toxic principle (Aconitine) in market and self prepared sample of Tribhuvankirti Rasa has been reduced by shodhana. In addition, flavonoids, glycosides and anti-oxidants are found which are beneficial for health.

Shwetra (Vitiligo) is a skin disease which takes longer time to cure. It affects the external beauty of the body causing social stigma, shyness, loss of confidence, fear of comments marital problems, etc. The disease needs repeated shodhana and regular internal and external shaman chikitsa for longer duration. Objectives: To study the efficacy of Vishakalpa (Shwetra lepa) alone in the management of Shwetra and to provide a potent drug for sure and quick relief from Shwetra (vitiligo), this pilot study was carried out. Material and methods: Shwetra lepa was prepared and used as local application in 15 patients having newly diagnosed patches of vitiligo. The changes in shape, size and number of patches and VETI score was assessed before and after treatment. The data was analyzed with the help of parametric and non parametric tests. Results: Though there was no significant change in VETI score, minimal reduction in shape and size of patches, daha and kandu was observed with Shwetra lepa vati. Conclusion: One month study duration for local application of Shwetra lepa vati and sample size was found to be insufficient to prove the efficacy of Shwetra lepa. Hence it is recommended that Shwetra lepa should be used alone for longer period up to 6 to 9 months or it can be used along with repeated shodhana and continuous shamana chikitsa for 2 to 6 months for effective results.