Can Friends Seed More Buzz and Adoption?

A critical element of word of mouth (WOM) or buzz marketing is to identify seeds, often central actors with high degree in the social network. Seed identification typically requires data on the full network structure, which is often unavailable. We therefore examine the impact of WOM seeding strategies motivated by the friendship paradox to obtain more central nodes without knowing network structure. But higher-degree nodes may communicate less with neighbors; therefore whether friendship paradox motivated seeding strategies increase or reduce WOM and adoption remains an empirical question. We develop and estimate a model of WOM and adoption using data on microfinance adoption across 43 villages in India for which we have data on social networks. Counterfactuals show that the proposed seeding strategies are about 15-20% more effective than random seeding in increasing adoption. Remarkably, they are also about 5-11% more effective than opinion leader seeding, and are relative more effective when we have fewer seeds

Can Random Friends Seed More Buzz and Adoption? Leveraging the Friendship Paradox

A critical element of word of mouth (WOM) or buzz marketing is to identify seeds, often central actors with high degree in the social network. Seed identification typically requires data on the full network structure, which is often unavailable. We therefore examine the impact of WOM seeding strategies motivated by the friendship paradox to obtain more central nodes without knowing network structure on adoption. Higher-degree nodes may be less effective as seeds if these nodes communicate less with neighbors or are less persuasive when they communicate; therefore whether friendship paradox motivated seeding strategies increase or reduce WOM and adoption remains an empirical question. We develop and estimate a model of WOM and adoption using data on microfinance adoption across 43 villages in India for which we have data on social networks. Counterfactuals show that the proposed seeding strategies are about 15-24% more effective in increasing adoption relative to random seeding. These strategies are also about 5-13% more effective than the firm’s leader seeding strategy, and are relatively more effective when we have fewer seeds

Slow Flow Past Porous Shell of Variable Permeability with Cavity at the Centre

In this paper slow flow of a viscous, incompressible fluid past a heterogeneous porous spherical shell with cavity is discussed. The permeability of porous sphere is varying with radial distance. Flow outside the porous spherical shell and inside the central cavity region is governed by the Stoke’s equation. Brinkman equation is used to analyze the flow inside the porous region. The boundary conditions used at the interface of porous and clear region are the continuity of velocity and stress. Exact solution of the problem is obtained and relevant quantities such as stream lines, velocity, pressure and drag on surface of the spherical shell are evaluated and exhibited graphically. The effect of various parameters on the flow has been discussed. Obtained results are useful for the flow past porous particles of variable permeability

An Efficient Image Segmentation Approach through Enhanced Watershed Algorithm

Image segmentation is a significant task for image analysis which is at the middle layer of image engineering. The purpose of segmentation is to decompose the image into parts that are meaningful with respect to a particular application. The proposed system is to boost the morphological watershed method for degraded images. Proposed algorithm is based on merging morphological watershed result with enhanced edge detection result obtain on pre processing of degraded images. As a post processing step, to each of the segmented regions obtained, color histogram algorithm is applied, enhancing the overall performance of the watershed algorithm. Keywords – Segmentation, watershed, color histogra

Analytical study of time-fractional order Klein–Gordon equation

AbstractIn this article, we study an approximate analytical solution of linear and nonlinear time-fractional order Klein–Gordon equations by using a recently developed semi analytical method referred as fractional reduced differential transform method with appropriate initial condition. In the study of fractional Klein–Gordon equation, fractional derivative is described in the Caputo sense. The validity and efficiency of the aforesaid method are illustrated by considering three computational examples. The solution profile behavior and effects of different fraction Brownian motion on solution profile of the three numerical examples are shown graphically

Expression of Four Methionine Sulfoxide Reductases in Staphylococcus aureus

Staphylococcus aureus possesses three MsrA enzymes (MsrA1, MsrA2, MsrA3) that reduce the S-epimer of methionine sulfoxide (MetO) and an MsrB enzyme that reduces R-MetO. The four msr genes are expressed from three different promoters. The msrA1/msrB genes are coexpressed. To determine the expression pattern of msr genes, three independent reporter strains were constructed where msr promoter was cloned in front of a promoterless lacZ and the resulting construct was integrated in the chromosome. Using these strains, it was determined that the msrA1/B expression is significantly higher in S. aureus compared to msrA2 or msrA3. Expression of msrA1/B was highest during stationary phase growth, but the expression of msrA2 and msrA3 was highest during the early to midexponential growth phase. Expression of msrA1/B was induced by oxacillin and the expression of msrA3 was upregulated by salt. Expression of msrA2 remained unchanged under all tested conditions

(TG/CA)(n )repeats in human gene families: abundance and selective patterns of distribution according to function and gene length

BACKGROUND: Creation of human gene families was facilitated significantly by gene duplication and diversification. The (TG/CA)(n )repeats exhibit length variability, display genome-wide distribution, and are abundant in the human genome. Accumulation of evidences for their multiple functional roles including regulation of transcription and stimulation of recombination and splicing elect them as functional elements. Here, we report analysis of the distribution of (TG/CA)(n )repeats in human gene families. RESULTS: The 1,317 human gene families were classified into six functional classes. Distribution of (TG/CA)(n )repeats were analyzed both from a global perspective and from a stratified perspective based on their biological properties. The number of genes with repeats decreased with increasing repeat length and several genes (53%) had repeats of multiple types in various combinations. Repeats were positively associated with the class of Signaling and communication whereas, they were negatively associated with the classes of Immune and related functions and of Information. The proportion of genes with (TG/CA)(n )repeats in each class was proportional to the corresponding average gene length. The repeat distribution pattern in large gene families generally mirrored the global distribution pattern but differed particularly for Collagen gene family, which was rich in repeats. The position and flanking sequences of the repeats of Collagen genes showed high conservation in the Chimpanzee genome. However the majority of these repeats displayed length polymorphism. CONCLUSION: Positive association of repeats with genes of Signaling and communication points to their role in modulation of transcription. Negative association of repeats in genes of Information relates to the smaller gene length, higher expression and fundamental role in cellular physiology. In genes of Immune and related functions negative association of repeats perhaps relates to the smaller gene length and the directional nature of the recombinogenic processes to generate immune diversity. Thus, multiple factors including gene length, function and directionality of recombinogenic processes steered the observed distribution of (TG/CA)(n )repeats. Furthermore, the distribution of repeat patterns is consistent with the current model that long repeats tend to contract more than expand whereas, the reverse dynamics operates in short repeats