Performance Analysis of Combined Discrete Fourier Transformation (DFT) and Successive Division based Image Watermarking Scheme

A combined Discrete Fourier Transformation (DFT) and Successive Division based image watermarking scheme has been proposed in this article. Due to intrinsic parameters: Imperceptibility, Data Embedding Capacity and Time of Execution, many spatial domain approaches are less efficient. Many frequency domain approaches satisfies imperceptibility and data embedding capacity, but utilizes more execution time. The proposed algorithm is a hybrid technique under frequency domain, which embeds watermark into host using Discrete Fourier Transformation (DFT) and successive division. Through DFT better imperceptibility is noticed and the algorithm utilizes very less execution time compared to other existing approaches. Performance analysis is done based on similarity between original and retrieved watermark images. The experimental results are better compared to other existing techniques.

Performance analysis of DCT and successive division based digital image watermarking scheme

In this article, a combined Discrete Cosine Transformation (DCT) and Successive Division based image watermarking scheme is proposed. In many spatial domain approaches, the watermark information is embedded into Least Significant Bits (LSBs) of host image. These LSBs are more vulnerable to noise and other unwanted information contents in the channel, in few cases these are subjected for modifications also. Many frequency domain approaches withstands LSB interference problem but utilizes more execution time. The proposed technique is a frequency domain approach which can withstand LSB attack and utilizes very less execution time than other existing approaches. Performance analysis is done based on robustness, imperceptibility, data embedding capacity and time of execution. The experimental results are better compared to other existing techniques.

Growth-driven displacement of protein aggregates along the cell length ensures partitioning to both daughter cells inCaulobacter crescentus

All living cells must deal with protein aggregation, which can occur as a result of experiencing stress. In the bacteriaEscherichia coliandMycobacterium smegmatis, aggregates collect at the cell poles and are retained over consecutive cell divisions only in the daughter cell that inherits the old pole, resulting in aggregation-free progeny within a few generations. Here we have studied thein vivokinetics of aggregate formation and clearance following heat and antibiotic stress inCaulobacter crescentus, which divides by a pre-programmed asymmetric cell cycle. Unexpectedly, we find that aggregates do not preferentially collect at the cell poles, but form as multiple distributed foci throughout the cell volume. Time-lapse microscopy revealed that under moderate stress, the majority of protein aggregates are short-lived and rapidly dissolved by the major chaperone DnaK and the disaggregase ClpB. Severe stress or genetic perturbation of the protein quality machinery results in long-lived protein aggregates, which individual cells can only clear by passing on to their progeny. Importantly, these persistent aggregates are neither collected at the old pole over multiple generations nor inherited exclusively by the old pole-inheriting stalked cell, but instead are partitioned between both daughter cells during successive division events in the same ratio. Our data indicate that this symmetric mode of aggregate inheritance is driven by the elongation and division of the growing mother cell. In conclusion, our study revealed a new pattern of aggregate inheritance in bacteria.

The RcvP Model

The theory of phonological structure (called ‘Radical CV Phonology’) is first outlined in Chapter 2. This theory is a development of Dependency Phonology. The chapter introduces a theory of elements and minimal vowel representations based on the Successive Division Algorithm. Other topics of relevance are underspecification, markednes, and enhancement. The model of Radical CV Phonology functions as the theoretical background of the set of elements that are active in the harmony systems that will be analyzed in Chapters 4–10 and is, as such, of interest to readers who want to know why we have these particular elements.

New Classes of Random Tessellations Arising from Iterative Division of Cells

We present new ideas about the type of random tessellation which evolves through successive division of its cells. These ideas are developed in an intuitive way, with many pictures and only a modicum of mathematical formalism–so that the wide application of the ideas is clearly apparent to all readers. A vast number of new tessellation models, with known probability distribution for the volume of the typical cell, follow from the concepts in this paper. There are other interesting models for which results are not presented (or presented only through simulation methods), but these models have illustrative value. A large agenda of further research is opened up by the ideas in this paper.

New Classes of Random Tessellations Arising from Iterative Division of Cells

We present new ideas about the type of random tessellation which evolves through successive division of its cells. These ideas are developed in an intuitive way, with many pictures and only a modicum of mathematical formalism–so that the wide application of the ideas is clearly apparent to all readers. A vast number of new tessellation models, with known probability distribution for the volume of the typical cell, follow from the concepts in this paper. There are other interesting models for which results are not presented (or presented only through simulation methods), but these models have illustrative value. A large agenda of further research is opened up by the ideas in this paper.

Somatic pairing, endomitosis and chromosome aberrations in snakes (Viperidae and Colubridae)

The positioning of macrochromosomes of Bothrops jararaca and Bothrops insularis (Viperidae) was studied in undistorted radial metaphases of uncultured cells (spermatogonia and oogonia) not subjected to spindle inhibitors. Colchicinized metaphases from uncultured (spleen and intestine) and cultured tissues (blood) were also analyzed. We report two antagonic non-random chromosome arrangements in untreated premeiotic cells: the parallel configuration with homologue chromosomes associated side by side in the metaphase plate and the antiparallel configuration having homologue chromosomes with antipolar distribution in the metaphase ring. The antiparallel aspect also appeared in colchicinized cells. The spatial chromosome arrangement in both configurations is groupal size-dependent and maintained through meiosis. We also describe, in untreated gonia cells, endomitosis followed by reductional mitosis which restores the diploid number. In B. jararaca males we observed that some gonad regions present changes in the meiotic mechanism. In this case, endoreduplicated cells segregate the diplochromosomes to opposite poles forming directly endoreduplicated second metaphases of meiosis with the suppression of first meiosis. By a successive division, these cells form nuclei with one set of chromosomes. Chromosome doubling in oogonia is known in hybrid species and in parthenogenetic salamanders and lizards. This species also presented chromosome rearrangements leading to aneuploidies in mitosis and meiosis. It is suggested that somatic pairing, endomitosis, meiotic alterations, and chromosomal aberrations can be correlated processes. Similar aspects of nuclei configurations, endomitosis and reductional mitosis were found in other Viperidae and Colubridae species.

A CONTRACTION ALGORITHM FOR FINDING ALL THE DC SOLUTIONS OF PIECEWISE-LINEAR CIRCUITS

An efficient algorithm for finding all the DC solutions of a broad class of piecewise-linear circuits, having hybrid representation, is described in this paper. Circuits belonging to this class can include electronic devices modelled by linear resistors, linear controlled sources, piecewise-linear two terminal resistors and independent sources. The algorithm is based on the idea of successive division and contraction of the solution domain. Two contraction methods are developed that result in a high rate of convergence of the computation process. Numerical examples and comparison analyses show the efficiency of this algorithm.