Pico Processor Using Verilog HDL

© ASEE 2009The Pico processor is a scaled down RISC processor hence the name “Pico”. Pico processors form an integral part in a network. They act as co-processors to Network processors. The network processors are in-charge of various complex functions such as routing, packet switching, queuing, encryption, decryption, pattern matching, computation and other such tasks. Many Pico processors work in parallel with the network processor, which leads to reduced computing time and improved performance (speed). This in turn increases the processing power of the network processor. One of the main uses of the Pico processor is to take care of the computation part of the network processor. Our project aims to further improve the performance of the network processor by increasing the processing speed of the Pico processor. We can do this by altering the architecture of the current Pico processors to accommodate a five stage pipeline. By doing so, we can manage to increase the speed of execution of each instruction by up to five times. The five stages which we have incorporated in our architecture are Instruction Fetch, Instruction Decode, Execute, Memory I/O and Write Back. The Pico processor is designed and simulated with ModelSim 6.2c. The logic synthesis of the Pico processor is performed using Quartus II software. The simulation results demonstrate the correct functions of the designed Pico processor. Significant performance enhancement has been observed in the designed Pico processor

Pluripotency reprogramming by competent and incompetent POU factors uncovers temporal dependency for Oct4 and Sox2

Oct4, along with Sox2 and Klf4 (SK), can induce pluripotency but structurally similar factors like Oct6 cannot. To decode why Oct4 has this unique ability, we compare Oct4-binding, accessibility patterns and transcriptional waves with Oct6 and an Oct4 mutant defective in the dimerization with Sox2 (Oct4(defSox2)). We find that initial silencing of the somatic program proceeds indistinguishably with or without Oct4. Oct6 mitigates the mesenchymal-to-epithelial transition and derails reprogramming. These effects are a consequence of differences in genome-wide binding, as the early binding profile of Oct4(defSox2) resembles Oct4, whilst Oct6 does not bind pluripotency enhancers. Nevertheless, in the Oct6-SK condition many otherwise Oct4-bound locations become accessible but chromatin opening is compromised when Oct4(defSox2) occupies these sites. We find that Sox2 predominantly facilitates chromatin opening, whilst Oct4 serves an accessory role. Formation of Oct4/Sox2 heterodimers is essential for pluripotency establishment; however, reliance on Oct4/Sox2 heterodimers declines during pluripotency maintenance

Photodegradation of organic pollutants RhB dye using UV simulated sunlight on ceria based TiO2 nanomaterials for antibacterial applications

To photo-catalytically degrade RhB dye using solar irradiation, CeO2 doped TiO2 nanocomposites were synthesized hydrothermally at 700 °C for 9 hrs. All emission spectra showed a prominent band centered at 442 nm that was attributed to oxygen related defects in the CeO2-TiO2 nanocrystals. Two sharp absorption bands at 1418 cm−1 and 3323 cm−1 were attributed to the deformation and stretching vibration, and bending vibration of the OH group of water physisorbed to TiO2, respectively. The photocatalytic activities of Ce-TiO2 nanocrystals were investigated through the degradation of RhB under UV and UV+ visible light over a period of 8 hrs. After 8 hrs, the most intense absorption peak at 579 nm disappeared under the highest photocatalytic activity and 99.89% of RhB degraded under solar irradiation. Visible light-activated TiO2 could be prepared from metal-ion incorporation, reduction of TiO2, non-metal doping or sensitizing of TiO2 using dyes. Studying the antibacterial activity of Ce-TiO2 nanocrystals against E. coli revealed significant activity when 10 μg was used, suggesting that it can be used as an antibacterial agent. Its effectiveness is likely related to its strong oxidation activity and superhydrophilicity. This study also discusses the mechanism of heterogeneous photocatalysis in the presence of TiO2