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Stevia a „Latin American herb‟ is the world‟s only natural sweetener with zero calories, zero carbohydrates and a zero glycemic index. In the present investigation, the in vitro regeneration of Stevia rebaudiana was performed through callogenesis and organogenesis from different explants (Leaves, Inter node, Shoot discs). Leaves explants showed best callus induction response when cultured on MS + (2.0 μM BAP + 1.0 μM NAA). However, the best callus initiation from leaf explants was obtained on MS medium supplemented with 1.0 μM NAA + 1.0 μM Kn. Optimization results of medium type and carbon source confirm 1X MS medium and glucose (3%) respectively best for callus initiation. Shoot initiation was achieved on 1X MS medium supplemented with 5.0 μM BAP + 1.0 μM NAA. In vitro raised shoots of Stevia showed best rooting on 1X MS + (1.0 μM IAA). The methanolic extracts of regenerated plants and callus culture of Stevia showed best antibacterial and antifungal activity against a number of microorganisms. Antiprotozoal activity of methanolic extract was also tested and found satisfactory. In vitro regeneration protocol of Stevia through callus culture is advantageous for enhanced multiplication of superior Stevia cultivars. Furthermore, callus from leaf explants can be a good source for production of antimicrobial and antiprotozoal compound of Stevia through bioreactor.

A low power, low noise amplifier (LNA) for 3.1-10.6 GHz ultra-wideband (UWB) wireless applications is reported in this paper. The proposed LNA is designed using common source (CS) current-reused architecture. Flat and high power gain (S21) with constant noise figure (NF) is achieved using series inductive peaking between CS primary stage and the current reused second stage. Input-output matching networks have been used to achieve acceptable values of input reflection coefficient (S11) and output reflection coefficient (S22) for the complete UWB frequency range. The use of inductive peaking with current reused architecture enhances the overall performance of proposed ultra-wideband LNA. The LNA is analyzed and designed using 32 nm CMOS process. It has a constant NF of 2.7 dB, a high and flat S21 of 23.8 ± 0.7 dB with high reverse isolation (S12) of < − 37.3 dB. The proposed LNA provides acceptable results for S11 and S22 parameters with values less than − 7.5 and − 11.0 dB respectively, for the UWB frequency range of 3.1-10.6 GHz. The proposed LNA provides 1-dB compression point (P1dB) of − 20 dBm and third order intercept point (IIP3) of − 10 dBm. The power consumed by the reported LNA is only 8.05 mW for a 0.7 V power supply. [ABSTRACT FROM AUTHOR]