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The demand for portability has speeded up the design of low-power electronic communication devices. Variable gain amplifier (VGA) is one of the most vulnerable elements of every modern receiver for the proper baseband processing of the signal. CMOS VGAs are generally suffered from low bandwidth and small gain range. In this research, a two-stage class AB VGA, each stage comprising of a direct transconductance amplifier and a linear transimpedance amplifier, is designed in Silterra 0.13-μm CMOS utilizing Mentor Graphics environment. The post-layout simulation results reveal that the VGA design achieves the widest bandwidth of 200 MHz and high gain range from -33 to 32 dB. The VGA dissipates only 2mW from a single 1.2 V DC supply. The core chip area of the VGA is also only 0.026 mm2 which is also the lowest compared to recent researches. Such a VGA will be a very useful module for all modern communication devices.

A cross sectional study was carried out to investigate the effects of mothers’ nutritional knowledge, health and nutritional factors and socio-economic parameters on school performance among class five students of University Laboratory School, Dhaka. All of the eighty students were selected for this study. This study found there is a strong relationship between mother’s knowledge score and school performance. It was found that mothers’ knowledge score was responsible for 91.1 percent change in school performance. The mean BMI of the mothers was 20.44. We found that the school performance measured by class roll number of the students is significantly related with mothers BMI. There was an imperfect negative association between socio-economic parameters and school performance. But the relationship between the school performances with socio-economic parameters was strongly significant. This study also observed the relationship between Individual Dietary Diversity Score (IDDS) of respondent and marks achieved in class 4 final exam. It is alarming that consumption percentage were low for eggs (30) and milk and milk products (37.5), but majority of the students who consumed milk and milk products (63.3%) and eggs (66.7%) got the highest marks.