48 research outputs found
A Comparative Study of Chisel for FPGA Design
This paper presents the results of a comparative study conducted into designing with the Chisel hardware construction language against the Verilog hardware description language across a range of standard-library and bespoke FPGA design components including an N-bit FIFO, a round-robin arbiter and a complex, scalable arbiter. Comparison metrics such as maximum operating frequency, silicon area, design flow run-time, source-code density and maintainability, simulation run-time and speed of coding are employed to evaluate the merits of designing with Chisel. Each component is implemented with a deep low-level hardware understanding with an aim to evaluate the merits of designing with Chisel from a hardware designers\u27 perspective. The authors discover Chisel\u27s merits for realising synthesizable repetitive designs such as in SoC development, experiencing the benefits of Chisel\u27s object-oriented background in enhancing code maintainability and scalability, and implementation efficiency. However, the authors foresee that Chisel will compliment rather than replace traditional HDLs for RTL design applications due to its limitations in terms of behavioural modelling
The Evolution of Labour Law in India: An Overview and Commentary on Regulatory Objectives and Development
Generally speaking there has been a relative dearth of serious scholarship focusing on the evolution of Indian labour law in its economic, social, and political contexts. Such work as there is tends to be constituted of fragmented and short journal articles and notes, including those by labour economists and industrial relations scholars. The present work undertakes a survey of the literature in the field, examining first the various periods through which Indian labour law has evolved up to the present time, and second the extent to which the labour law system can be seen to have fulfilled its two core objectives: the protection of labour and the maintenance of industrial peace. The survey reveals that Indian “labour law” in the formal sense has very little purchase in terms of its application in pursuit of its objects. This, in turn,
suggests that some other approach is required to reach a more grounded and accurate understanding of how, and to what effect, labour is regulated in India
Block-based Classification Method for Computer Screen Image Compression
In this paper, a high accuracy and reduced processing time block based classification method for computer screen images is presented. This method classifies blocks into five types: smooth, sparse, fuzzy, text and picture blocks. In a computer screen compression application, the choice of block compression algorithm is made based on these block types. The classification method presented has four novel features. The first novel feature is a combination of Discrete Wavelet Transform (DWT) and colour counting classification methods. Both of these methods have only been used for computer image compression in isolation in previous publications but this paper shows that combined together more accurate results are obtained overall. The second novel feature is the classification of the image blocks into five block types. The addition of the fuzzy and sparse block types make the use of optimum compression methods possible for these blocks. The third novel feature is block type prediction. The prediction algorithm is applied to a current block when the blocks on the top and the left of the current block are text blocks or smooth blocks. This new algorithm is designed to exploit the correlation of adjacent blocks and reduces the overall classification processing time by 33%. The fourth novel feature is down sampling of the pixels in each block which reduces the classification processing time by 62%. When both block prediction and down sampling are enabled, the classification time is reduced by 74% overall. The overall classification accuracy is 98.46%
Bacterial Antigen Expression Is an Important Component in Inducing an Immune Response to Orally Administered Salmonella-Delivered DNA Vaccines
BACKGROUND: The use of Salmonella to deliver heterologous antigens from DNA vaccines is a well-accepted extension of the success of oral Salmonella vaccines in animal models. Attenuated S. typhimurium and S. typhi strains are safe and efficacious, and their use to deliver DNA vaccines combines the advantages of both vaccine approaches, while complementing the limitations of each technology. An important aspect of the basic biology of the Salmonella/DNA vaccine platform is the relative contributions of prokaryotic and eukaryotic expression in production of the vaccine antigen. Gene expression in DNA vaccines is commonly under the control of the eukaryotic cytomegalovirus (CMV) promoter. The aim of this study was to identify and disable putative bacterial promoters within the CMV promoter and evaluate the immunogenicity of the resulting DNA vaccine delivered orally by S. typhimurium. METHODOLOGY/PRINCIPAL FINDINGS: The results reported here clearly demonstrate the presence of bacterial promoters within the CMV promoter. These promoters have homology to the bacterial consensus sequence and functional activity. To disable prokaryotic expression from the CMV promoter a series of genetic manipulations were performed to remove the two major bacterial promoters and add a bacteria transcription terminator downstream of the CMV promoter. S. typhimurium was used to immunise BALB/c mice orally with a DNA vaccine encoding the C-fragment of tetanus toxin (TT) under control of the original or the modified CMV promoter. Although both promoters functioned equally well in eukaryotic cells, as indicated by equivalent immune responses following intramuscular delivery, only the original CMV promoter was able to induce an anti-TT specific response following oral delivery by S. typhimurium. CONCLUSIONS: These findings suggest that prokaryotic expression of the antigen and co-delivery of this protein by Salmonella are at least partially responsible for the successful oral delivery of C-fragment DNA vaccines containing the CMV promoter by S. typhimurium
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Laser Drilling: Drilling with the Power of Light Phase 1: Feasibility Study
A laser drilling research team was formed from members of academia, industry and national laboratory to explore the feasibility of using modern high-powered lasers to drill and complete oil and gas wells. The one-year Phase 1 study discussed in this report had the goals of quantifying the amount of pulsed infrared laser energy needed to spall and melt rock of varying lithologies and to investigate the possibility of accomplishing the same task in water under atmospheric conditions. Previous work by some members of this team determined that continuous wave lasers of varying wavelengths have more than enough power to cut, melt and vaporize rock. Samples of sandstone, limestone, and shale were prepared for laser beam interaction with a 1.6 kW pulsed Nd:YAG laser beam to determine how the beam's size, power, repetition rate, pulse width, exposure time and energy can affect the amount of energy transferred to the rock for the purposes of spallation, melting and vaporization. The purpose of the laser rock interaction experiment was to determine the threshold parameters required to remove a maximum rock volume from the samples while minimizing energy input. Absorption of radiant energy from the laser beam gives rise to the thermal energy transfer required for the destruction and removal of the rock matrix. Results from the tests indicate that each rock type has a set of optimal laser parameters to minimize specific energy (SE) values as observed in a set of linear track and spot tests. In addition, it was observed that the rates of heat diffusion in rocks are easily and quickly overrun by absorbed energy transfer rates from the laser beam to the rock. As absorbed energy outpaces heat diffusion by the rock matrix, local temperatures can rise to the melting points of the minerals and quickly increase observed SE values. The lowest SE values are obtained in the spalling zone just prior to the onset of mineral melt. The current study determined that using pulsed lasers could accomplish removing material from rock more efficiently than continuous wave lasers. The study also determined that reducing the effect of secondary energy absorbing mechanisms resulted in lower energy requirements in shale and, to some extent, in sandstones. These secondary mechanisms are defined as physical processes that divert beam energy from directly removing rock, and may include thermally-induced phase behavior changes of rock minerals (i.e., melting, vaporization, and dissociation) and fractures created by thermal expansion. Limestone is spalled by a different mechanism and does not seem to be as affected by secondary mechanisms. It was also shown that the efficiency of the cutting mechanism improved by saturating porous rock samples with water, and that a laser beam injected directly through a water layer at a sandstone sample was able to spall and melt the sample
A Putative P-Type ATPase Required for Virulence and Resistance to Haem Toxicity in Listeria monocytogenes
Regulation of iron homeostasis in many pathogens is principally mediated by the ferric uptake regulator, Fur. Since acquisition of iron from the host is essential for the intracellular pathogen Listeria monocytogenes, we predicted the existence of Fur-regulated systems that support infection. We examined the contribution of nine Fur-regulated loci to the pathogenicity of L. monocytogenes in a murine model of infection. While mutating the majority of the genes failed to affect virulence, three mutants exhibited a significantly compromised virulence potential. Most striking was the role of the membrane protein we designate FrvA (Fur regulated virulence factor A; encoded by frvA [lmo0641]), which is absolutely required for the systemic phase of infection in mice and also for virulence in an alternative infection model, the Wax Moth Galleria mellonella. Further analysis of the ΔfrvA mutant revealed poor growth in iron deficient media and inhibition of growth by micromolar concentrations of haem or haemoglobin, a phenotype which may contribute to the attenuated growth of this mutant during infection. Uptake studies indicated that the ΔfrvA mutant is unaffected in the uptake of ferric citrate but demonstrates a significant increase in uptake of haem and haemin. The data suggest a potential role for FrvA as a haem exporter that functions, at least in part, to protect the cell against the potential toxicity of free haem
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Imbalanced social-communicative and restricted repetitive behavior subtypes of autism spectrum disorder exhibit different neural circuitry
Abstract: Social-communication (SC) and restricted repetitive behaviors (RRB) are autism diagnostic symptom domains. SC and RRB severity can markedly differ within and between individuals and may be underpinned by different neural circuitry and genetic mechanisms. Modeling SC-RRB balance could help identify how neural circuitry and genetic mechanisms map onto such phenotypic heterogeneity. Here, we developed a phenotypic stratification model that makes highly accurate (97–99%) out-of-sample SC = RRB, SC > RRB, and RRB > SC subtype predictions. Applying this model to resting state fMRI data from the EU-AIMS LEAP dataset (n = 509), we find that while the phenotypic subtypes share many commonalities in terms of intrinsic functional connectivity, they also show replicable differences within some networks compared to a typically-developing group (TD). Specifically, the somatomotor network is hypoconnected with perisylvian circuitry in SC > RRB and visual association circuitry in SC = RRB. The SC = RRB subtype show hyperconnectivity between medial motor and anterior salience circuitry. Genes that are highly expressed within these networks show a differential enrichment pattern with known autism-associated genes, indicating that such circuits are affected by differing autism-associated genomic mechanisms. These results suggest that SC-RRB imbalance subtypes share many commonalities, but also express subtle differences in functional neural circuitry and the genomic underpinnings behind such circuitry
The Evolution of Labour Law in India: An Overview and Commentary on Regulatory Objectives and Development
Generally speaking there has been a relative dearth of serious scholarship focusing on the evolution of Indian labour law in its economic, social, and political contexts. Such work as there is tends to be constituted of fragmented and short journal articles and notes, including those by labour economists and industrial relations scholars. The present work undertakes a survey of the literature in the field, examining first the various periods through which Indian labour law has evolved up to the present time, and second the extent to which the labour law system can be seen to have fulfilled its two core objectives: the protection of labour and the maintenance of industrial peace. The survey reveals that Indian “labour law” in the formal sense has very little purchase in terms of its application in pursuit of its objects. This, in turn,
suggests that some other approach is required to reach a more grounded and accurate understanding of how, and to what effect, labour is regulated in India
The Evolution of Labor Law in Three Asian Nations: An Introductory Comparative Study
The purpose of this Article is to contribute to provide a historical account of the evolution of labor law in three countries: India, Indonesia, and China.' Our founding question is how do we understand, or how do we explain, the evolution of labor law in these countries, and what does this understanding add to the present discourse?
In particular, what do our studies tell us about the prominent issue of "legal origins" (i.e., the extent to which the labor market systems in India, Indonesia, and China have been characterized by the regulatory style of the systems from which their labor laws were initially drawn); and the extent to which the labor law systems of those countries been shaped under the influence of international pressures