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This paper presents a design of 2.4 GHz folded subharmonic active mixer in TSMC 130 nm CMOS process for direct conversion receiver (DCR). To achieve the low supply voltage, the folded topology is adopted for the proposed subharmonic mixer. The complementary current reuse structure is used as RF transconductance stage where the biasing for the PMOS and NMOS transistors are self-biased by a resistor to support high conversion gain at low supply voltage. Frequency doubling operation is done by the mixing core which is driven by a quadrature local oscillator (LO) signals. The proposed mixer is designed and simulated using ADS (Advanced Design System) simulator with Cadence software. It produces 10.5 dB conversion gain, a single sideband) noise figure of 9.5 dB, 2 LO-to-RF isolation of 53 dB, LO-to-RF isolation of 117 dB, RF-to-IF isolation of 55 dB and IIP3 of -7.5 dBm. The quadrature LO subharmonic mixer consumes 824µW power from a supply voltage of 0.8 V. The proposed mixer is compared with existing subharmonic mixers. The comparison shows the proposed subharmonic mixer gives a good Figure of Merit. [ABSTRACT FROM AUTHOR]

The field experiment was carried out in the orchard, Horticultural College and Research Institute, TNAU, Coimbatore from September 2016 to April 2017 to monitor the seasonal abundance of insect pests by installing colored sticky traps. The experiment result showed that the maximum number of A. gosypii was trapped on yellow sticky traps with the meantrap catches of 50.68 A. gosypii per trap per week followed by 9.75 A. gosypii in blue sticky traps as against the minimum number of 1.70 A. gosypii in a red sticky trap. The maximum number of A. dispersus was trapped on yellow sticky traps with the mean trap catches of 34.82 per trap per week followed by 10.46 in blue sticky traps as against the minimum number of 1.68 spiraling whiteflies in a red sticky trap. The maximum number of B. tabaci was trapped on yellow sticky traps with the meantrap catches of 14.83 per trap per week followed by 6.01 in blue sticky traps as against the minimum number of 0.73 whiteflies in a red sticky trap. [ABSTRACT FROM AUTHOR]

Cassia angustifolia Vahl. is an important medicinal plant belonging to the family Leguminaceae. Like other plants, medicinal plants too have to bear the attack of injurious insect pests. Extensive monitoring and development of eco-friendly pest management practices are essential in the production of high quality, pesticide residue free produces. Results of field experiments revealed that among the treatments, foliar application of chlorpyriphos 20 EC (standard check) @1.0 L/ha was significantly superior over all other treatments, recording the lowest number of pod borer and the untreated control was significantly inferior, recording maximum number of pod borers per plant. Among the biopesticides tested, neem seed kernel extract 5 per cent showed maximum efficacy with the least number of pod borer per plant, followed by neem oil 3 per cent, Bacillus thuringiensis @ 750g/ha and Beauveria bassiana @ 2 kg/ha, which were statistically on par in their efficacy. Results on the efficacy of biopesticides on pod damage revealed that Bacillus thuringiensis @ 750 g/ha showed promising efficacy with the minimum pod damage at 14 DAT, followed by neem seed kernel extract 5 per cent. Regarding yield, neem seed kernel extract 5 per cent treated plots recorded maximum leaf and pod (dry) yield followed by neem oil 3 per cent and Bacillus thuringiensis @ 750 g/ha. Hence, neem seed kernel extract 5 per cent can be recommended as suitable biopesticide for the management of pod borer, Etiella zinckenella infesting senna, C. angustifolia. [ABSTRACT FROM AUTHOR]

A field experiment was conducted in the farmer's holdings at Kalathupudhur village, Coimbatore district in Tamil Nadu during 2015-2016. Experimental results revealed that the maximum number of PDI were recorded in untreated control 86.86 per cent followed by famer's practise 52 per cent, as minimum number of PDI were recorded in IPM plot 14.20 per cent at 121 DAS. Regarding fruit yield parameters, maximum numbers of harvestable fruits were recorded in IPM plot (11.85), followed by farmer's practice (8.28) as against lowest number of 4.71 fruits per plant in untreated control. The maximum fruit yield of 34.12 tonnes per ha was recorded in IPM plot followed by farmer's practise 22.53 tonnes per ha, as against the minimum fruit yield and cost benefit ratio of 8.62 tonnes per ha in untreated control, respectively. Based on the experimental results revealed that the IPM strategy was significantly superior to farmer's practice and untreated control in reducing the per cent disease incidence, number of fruits per plant and fruits yield. [ABSTRACT FROM AUTHOR]

Laboratory bioassays were conducted to investigate the safety of EC formulations of Strychnus nux-vomica extracts to Trichogramma chilonis Ishii and Chrysoperla zastrowi silemi Esben-Petersen. The results revealed that the formulations are safe to natural enemies at the lower concentrations. All the treatments recorded greater than 80 per cent egg parasitizaton and adult emergence of T. chilonis Ishii, other than hexane leaf extract 4 per cent and hexane seed extract 3 and 4 per cent. More than 80 percent of egg hatchability, adult longetivity and oviposition of C. zastrowi silemi were recorded at the lowest concentration of hexane leaf and seed formulations. [ABSTRACT FROM AUTHOR]

Field experiments were carried out in farmer's holdings at Coimbatore and Tirupur districts of Tamil Nadu during June, 2012 to September, 2012 to assess the efficacy of botanical pesticides against sucking pests and defoliators infesting Solanum nigrum. Foliar application of profenophos @ 2 ml per litre was effective against sucking pests as well as defoliators with maximum leaf yield of 22.40 kg/12m² harvest as against 11.45 kg/12m² harvest in untreated control. Azadirachtin one per cent and aqueous leaf extract of Andrographis paniculata 2% recorded maximum reduction in pest population and also conserved more number of predatory coccinellids. [ABSTRACT FROM AUTHOR]

The composition and diversity of the gut microbiota are known to be different between babies and adults. The aim of this project was to compare the level of bifidobacteria between babies and adults and to investigate the influence of lifestyle factors on the level of this bacterium in the gut. During this study, the levels of bifidobacteria in 10 human babies below 2 years of age were compared with that of 10 human adults above 40 years. The level of bifidobacteria proved to be significantly higher in babies in comparison with adults. This investigation concluded that a combination of several factors, such as age, diet, and BMI, has an important effect on the level of bifidobacteria in adults, while in babies, a combination of diet and age may influence the level of intestinal bifidobacteria.