Rapid identification of diarrheagenic Escherichia coli based on barcoded magnetic bead hybridization

This paper presents the design and implement a basic five stage pipelined MIPS-32 CPU. Particular attention will be paid to the reduction of clock cycles for lower instruction latency as well as taking advantage of high-speed components in an attempt to reach a clock speed of at least 100 MHz. The final results allowed the CPU to be run at over 200 MHz with a very reasonable chip area of around 900,000 nm2.

https://zenodo.org/record/33247/files/Vhdl_Implementation_of_A_Mips-32_Pipeline_Processor.pdf

Vhdl Implementation of A Mips-32 Pipeline Processor

Salmonella Typhi and Salmonella Paratyphi A are the leading causative agents of enteric fever which cause morbidity and mortality worldwide. Currently, there is no combination vaccine which could protect infection from both the strains. In this paper, we are focusing on the development of a novel bivalent typhoidal Outer Membrane Vesicles (OMVs) based immunogen against enteric fever. We have isolated Salmonella Typhi and Paratyphi A OMVs and also characterized OMVs associated antigens. Then we immunized adult mice with three doses of our newly formulated bivalent immunogen orally (25 μg/200 μl). After three doses of oral immunization, we found our immunogen could significantly induce humoral response. We have also found serum IgG against LPS, Vi-polysaccharide etc. OMV immunization induces CD4, CD8 and CD19 population in immunized mice spleen. It also induces Th1 and Th17-cell mediated immunity. We also found bivalent OMVs immunization can prevent more than lethal dose of heterologous Salmonella strains mediated systemic infection in adult mice model. We determined that, the protective immune responses depend on the humoral and cell-mediated immune response. Furthermore, we have evaluated the mode of protective immune response carried out by anti-OMVs antibody by significantly inhibiting bacterial motility and mucin penetration ability. Taken together, these findings suggest that our bivalent immunogen could be used as a novel candidate vaccine against enteric fever.

/pdf/development-of-a-novel-s-typhi-and-paratyphi-a-outer-2a9qmm33sh.pdf

Development of a novel S. Typhi and Paratyphi A outer membrane vesicles based bivalent vaccine against enteric fever.

The paper describes the design and synthesis of a basic 5 stage pipelined MIPS-32 processor for finding the longer path delay using different process technologies. The large propagation delay or critical path within the circuit and improving the hardware which causes delay is a standard method for increasing the performance. The organization of pipeline stages in such a way that pipeline can be clocked at a high frequency. The design has been synthesized at different process technologies targeting using Spartan3, Spartan6, Virtex4, Virtex5 and Virtex6 devices. The synthesis report indicates that critical path delay is located in execution unit. The maximum critical path delay is 41.405ns at 90nm technology and minimum critical path delay is 6.57ns at 40nm technology. The performance comparison result at different technologies shows that pipeline processor can work at 178MHz in 40nm technology i.e. 49.7% better than other technologies.

Performance Improvement in MIPS Pipeline Processor based on FPGA

The aim of the work is to design and reduce the power consumption of low power 32 bits RISC core processor. The design is based on 5-stage pipelined DLX architecture. This paper proposes the design for the low power RISC processor. The DLX architecture with pipelined control in a RISC core consists of Fetch, Decode, Execute, Pipeline Control and Memory. The reduction in the power is achieved using HDL modification technique. Leakage power i.e Quiescent power which is also a static power in the processor cannot be reduced. Algorithm modification in the execute block of the RISC core will reduce the power consumed by the processor. 13.33% is the total power reduction between a normal processor and the low power version of the processor.

FPGA Based Implementation of Power Optimization of 32 Bit RISC Core Using DLX Architecture

The paper describes the architecture and design of the pipelined execution unit of a 32-bit RISC processor. Organization of the blocks in different stages of pipeline is done in such a way that pipeline can be clocked at high frequency. Control and forward of `data flow' among the stages are taken care by dedicated hardware logic. Different blocks of the execution unit and dependency among themselves are explained in details with the help of relevant block diagrams. The design has been modeled in verilog HDL and functional verification policies adopted for it have been described thoroughly. Synthesis of the design is carried out at 0.13-micron standard cell technology and for slow timing library the reported frequency of operation is 714 MHz at synthesis level.

Design of High-Speed-Pipelined Execution Unit of 32-bit RISC Processor

Trends in the genomic epidemiology of Vibrio cholerae O1 isolated worldwide since 1961

Shigellosis is a diarrheal disease that is prevalent in developing countries and especially dangerous in young children. Currently, animal models for shigellosis are unable to model some aspects of the infectious cycle. Here, we describe a new shigellosis model in adult zebrafish, an increasingly common model organism for studying bacterial pathogens. The zebrafish model can be used to study Shigella colonization, transmission, and immune responses, as well as test vaccine efficacy. ABSTRACT Shigellosis has been a menace to society for ages. The absence of an effective vaccine against Shigella, improper sanitation, and unhygienic use of food and water allow the disease to flourish. Shigella can also be transmitted via natural water bodies. In the absence of a good animal model, the actual nature of pathogenesis and transmission remains unclear. Zebrafish larvae have previously been described as a model for Shigella pathogenesis. However, larval fish lack a mature intestinal microbiota and immune system. Here, the adult zebrafish was assessed as a potential model for Shigella pathogenesis. Their well-developed innate and adaptive immune responses mimic the mammalian immune system. Shigella showed a clear dose-, time-, and temperature-dependent colonization of the adult zebrafish gut. Efficacy of a three-dose immunization regime was tested using bath immunization with heat-killed trivalent Shigella immunogen. The present study demonstrates the efficacy of an adult zebrafish model for pathogenesis, transmission, and vaccine efficacy studies. IMPORTANCE Shigellosis is a diarrheal disease that is prevalent in developing countries and especially dangerous in young children. Currently, animal models for shigellosis are unable to model some aspects of the infectious cycle. Here, we describe a new shigellosis model in adult zebrafish, an increasingly common model organism for studying bacterial pathogens. The zebrafish model can be used to study Shigella colonization, transmission, and immune responses, as well as test vaccine efficacy.

An Experimental Adult Zebrafish Model for Shigella Pathogenesis, Transmission, and Vaccine Efficacy Studies

Studies on formulation of a combination heat killed immunogen from diarrheagenic Escherichia coli and Vibrio cholerae in RITARD model.

Objectives: We have isolated a total of five newer cholera phages which are novel broad host range to incorporate with the existing phage typing schemes for an extended typing scheme. Materials and Methods: These newly isolated phages were well characterized including the electron micrograph. A total of 300 Vibrio cholerae strains were isolated from the different endemic region in India were included in phage typing study. Results: These phages were found different from the existing phages. Electron microscopic results showed that the phages belonged to myophage and podophage group. Characterization of the phages based on pH, temperature, and organic solvent sensitivity showed differences among the phages used in this study. All the strains of Vibrio O1 were typeable (100%) with the five set of cholera phages. Of these, 40% strains were clustered under Type-1. Conclusion: The newer Vibrio phages are novel and broad host range and will be useful to incorporate with the existing phage typing system for more precisely discriminate the strains of Vibrio cholerae.

Sounak Sarkar

Papers

Design of High-Speed-Pipelined Execution Unit of 32-bit RISC Processor

Trends in the genomic epidemiology of Vibrio cholerae O1 isolated worldwide since 1961

An Experimental Adult Zebrafish Model for Shigella Pathogenesis, Transmission, and Vaccine Efficacy Studies

Studies on formulation of a combination heat killed immunogen from diarrheagenic Escherichia coli and Vibrio cholerae in RITARD model.

Isolation and characterization of novel broad host range bacteriophages of Vibrio cholerae O1 from Bengal