The H-Line Signed Graph of a Signed Graph

For standard terminology and notion in graph theory we refer the reader to Harary; the non-standard will be given in this paper as and when required. We treat only finite simple graphs without self loops and isolates

Mobile Apps as Supplements of a Typical Discrete Mathematics Course: Benefits, Features, and Design Elements

Mobile Apps have tremendous potential for use as very effective supplements to the exiting learning modalities in a typical introductory Discrete Mathematics course. In this article we consider the general nature of a typical introductory Discrete Mathematics courses and derive elements of design which are expected to make the mobile Apps intended for use as supplements to such a course more effective. We enumerate the elements of the topical coverage and inherent characteristics of typical introductory Discrete Mathematics course, and the benefits of a mobile App course supplement. We then present the design aspects and desired salient features of mobile Apps intended for uses as supplements in a typical introductory Discrete Mathematics course, and the elements of user experience (UX) of such an App. We believe that several of these design elements could be adapted across several different courses and disciplines to enhance the learning experience

Microrheology of non mulberry silk varieties by optical tweezer and video microscopy based techniqueas

We have carried out a comparative study of the microrheol. properties of silk fibroin solns. formed from a variety of silks indigenous to the Indian subcontinent. We present the measured viscoelastic moduli of Tasar silk fibroin soln. using both a single and dual optical tweezer at 0.16​% and 0.25​% (w​/v)​. The bandwidth of the measurements carried out using optical tweezers is extended down to the lower frequency regime by a video microscopy measurement. Further, we have measured the viscoelastic moduli of Eri and Muga varieties of silk fibroin solns. at a higher concn. (1.00​% w​/v) limiting the tool of measurement to video microscopy, as the reduced optical transparencies of these solns. at higher concn. preclude an optical tweezer based investigation. The choice of a higher concn. of fibroin soln. of the latter silk varieties is so as to enable a comparison of the shear moduli obtained from optical methods with their corresponding fiber stiffness obtained from wide angle X-​ray scattering data. We report a correlation between the microstructure and microrheol. parameters of these silk varieties for the concn. of fibroin solns. studied

Magnetic stress as a driving force of structural distortions: the case of CrN

We show that the observed transition from rocksalt to orthorhombic P$_{nma}$ symmetry in CrN can be understood in terms of stress anisotropy. Using local spin density functional theory, we find that the imbalance between stress stored in spin-paired and spin-unpaired Cr nearest neighbors causes the rocksalt structure to be unstable against distortions and justifies the observed antiferromagnetic ordering. This stress has a purely magnetic origin, and may be important in any system where the coupling between spin ordering and structure is strong.Comment: 4 pages (two columns) 4 figure

Monomeric PcrA helicase processively unwinds plasmid lengths of DNA in the presence of the initiator protein RepD

The helicase PcrA unwinds DNA during asymmetric replication of plasmids, acting with an initiator protein, in our case RepD. Detailed kinetics of PcrA activity were measured using bulk solution and a single-molecule imaging technique to investigate the oligomeric state of the active helicase complex, its processivity and the mechanism of unwinding. By tethering either DNA or PcrA to a microscope coverslip surface, unwinding of both linear and natural circular plasmid DNA by PcrA/RepD was followed in real-time using total internal reflection fluorescence microscopy. Visualization was achieved using a fluorescent single-stranded DNA-binding protein. The single-molecule data show that PcrA, in combination with RepD, can unwind plasmid lengths of DNA in a single run, and that PcrA is active as a monomer. Although the average rate of unwinding was similar in single-molecule and bulk solution assays, the single-molecule experiments revealed a wide distribution of unwinding speeds by different molecules. The average rate of unwinding was several-fold slower than the PcrA translocation rate on single-stranded DNA, suggesting that DNA unwinding may proceed via a partially passive mechanism. However, the fastest dsDNA unwinding rates measured in the single-molecule unwinding assays approached the PcrA translocation speed measured on ssDNA

A Distributed Algorithm for the Classification of Images on a Network of Workstations

Image databases require content-based queries and retrievals. Fast and accurate retrievals for user queries depend on efficient indexing and searching schemes. The classification of images into different categories (classes) is an important task which facilitates the indexing and searching process. The classification of huge amounts of image data place enormous demands on computational requirements. Network of workstations (NOWs, also sometimes called clusters) are a cost-effective way of providing the much-needed computational power in such applications. This paper presents a distributed scheme for the classification of images in an image database, using a network of workstations. The results of the classification and the speedups obtained using a cluster, establish the effectiveness of the proposed scheme

Multimedia Databases

The acquisition, generation, storage and processing of multimedia data in computers and transmission over networks have grown tremendously. Databases have been developed to cope with huge amounts of data in different applications. Multimedia databases (MMDB) are essential for efficient management and effective use of this data. They are however still in their infancy. Most current MMDB system prototypes are closely bound to narrow application areas. Experiences gained from developing and using novel multimedia will help advance the multimedia database technology