Comparative Analysis of Bit Error Rate and Outage Capacity for MIMO Space Time Trellis Coding

In this paper, we have first given brief introduction to Multiple Inputs Multiple Outputs (MIMO) systems. After that different MIMO models and their capacity is discussed. We have compared bit error rate of different modulation techniques like Phase Shift Keying (PSK), Quadrature Amplitude Modulation i.e. QAM 16, QAM 32, QAM 64 using Space Time Trellis Coding (STTC). The outage capacity and bit error rate of MIMO and MISO have also been compared. The Rank criterion is used for maximizing the rank of transmitting antennas matrix in STTC. The proposed technique increases spatial diversity and coding gain of MIMO channels

The Role of Coupled Positive Feedback in the Expression of the SPI1 Type Three Secretion System in Salmonella

Salmonella enterica serovar Typhimurium is a common food-borne pathogen that induces inflammatory diarrhea and invades intestinal epithelial cells using a type three secretion system (T3SS) encoded within Salmonella pathogenicity island 1 (SPI1). The genes encoding the SPI1 T3SS are tightly regulated by a network of interacting transcriptional regulators involving three coupled positive feedback loops. While the core architecture of the SPI1 gene circuit has been determined, the relative roles of these interacting regulators and associated feedback loops are still unknown. To determine the function of this circuit, we measured gene expression dynamics at both population and single-cell resolution in a number of SPI1 regulatory mutants. Using these data, we constructed a mathematical model of the SPI1 gene circuit. Analysis of the model predicted that the circuit serves two functions. The first is to place a threshold on SPI1 activation, ensuring that the genes encoding the T3SS are expressed only in response to the appropriate combination of environmental and cellular cues. The second is to amplify SPI1 gene expression. To experimentally test these predictions, we rewired the SPI1 genetic circuit by changing its regulatory architecture. This enabled us to directly test our predictions regarding the function of the circuit by varying the strength and dynamics of the activating signal. Collectively, our experimental and computational results enable us to deconstruct this complex circuit and determine the role of its individual components in regulating SPI1 gene expression dynamics

Discutindo a educação ambiental no cotidiano escolar: desenvolvimento de projetos na escola formação inicial e continuada de professores

A presente pesquisa buscou discutir como a Educação Ambiental (EA) vem sendo trabalhada, no Ensino Fundamental e como os docentes desta escola compreendem e vem inserindo a EA no cotidiano escolar., em uma escola estadual do município de Tangará da Serra/MT, Brasil. Para tanto, realizou-se entrevistas com os professores que fazem parte de um projeto interdisciplinar de EA na escola pesquisada. Verificou-se que o projeto da escola não vem conseguindo alcançar os objetivos propostos por: desconhecimento do mesmo, pelos professores; formação deficiente dos professores, não entendimento da EA como processo de ensino-aprendizagem, falta de recursos didáticos, planejamento inadequado das atividades. A partir dessa constatação, procurou-se debater a impossibilidade de tratar do tema fora do trabalho interdisciplinar, bem como, e principalmente, a importância de um estudo mais aprofundado de EA, vinculando teoria e prática, tanto na formação docente, como em projetos escolares, a fim de fugir do tradicional vínculo “EA e ecologia, lixo e horta”.Facultad de Humanidades y Ciencias de la Educació

Coordinated regulation of the flagellar, Salmonella pathogenicity island 1, and the type I fimbriae gene networks in Salmonella typhimurium

Micro-organisms are constantly monitoring their surrounding environment and making important lifestyle decisions. This decision process is governed by large genetic networks that process the information leading to a phenotypic response from the cell. Using the food-borne pathogen, Salmonella, as a model organism, we try to investigate how cells encode strategies in networks to optimally control cellular behavior. Salmonella, on ingestion with contaminated food, swims in small intestine using propeller-like structures, flagella, on its surface. On reaching the site of infection, it assembles a hypodermic needle on its surface using which it injects proteins into host cells. These proteins cause a change in the host-cell shape leading to internalization of the bacterium. If the bacterium fails to get internalized, it assembles finger-like projections, fimbriae, on its surface to adhere to and persist in the intestine. How Salmonella dynamically regulates gene expression and assembly of these organelles is the focus of this study. Our results demonstrate that the networks controlling genes necessary for flagella, needle, and fimbriae are designed so as to encode logic gates and limit expression to conditions optimum for infection. In addition, there is cross-talk between these three systems which serves to dynamically control the timing of activation and de-activation of these networks. Collectively, we demonstrate that cells dynamically process information in genetic networks which ensures that the encoded products are produced at the correct locales, at the appropriate levels, and for the appropriate amount of time

Evolution of intrinsic microbial resistance to antibiotics in bacteria

by Supreet Sain

Coordinated control of flagellar, needle, and fimbriae genes in Salmonella

by Supreet Sain

Role of Fur in regulating pathogenic gene expression in enteric bacteria

by Supreet Sain

Role of efflux systems in regulating the concentration of cellular metabolic intermediates concentration and its impact on biofuel production

by Supreet Sain

Academic Ethics at the Undergraduate Level: Case Study from the Formative Years of the Institute

Academic ethics among students at an undergraduate level are dictated by a variety of factors. Institutional cultures, personal preferences and notions of ethics, external factors, and peer-pressure are some of the factors that play an important role in the ethical behavior of an undergraduate student. The present study is an attempt to understand the student behavior in a three year old technical Institute in India. At a time when the higher technical education sector in India is rapidly expanding, the study presents trends in undergraduate students regarding academic ethics. The study highlights the factors that are most important in governing ethical behavior of students, and allow for corrective measures at a formative stage in the Institute’s life.by Supreet Sain