Canonical correlation analysis of high-dimensional data with very small sample support

This paper is concerned with the analysis of correlation between two high-dimensional data sets when there are only few correlated signal components but the number of samples is very small, possibly much smaller than the dimensions of the data. In such a scenario, a principal component analysis (PCA) rank-reduction preprocessing step is commonly performed before applying canonical correlation analysis (CCA). We present simple, yet very effective approaches to the joint model-order selection of the number of dimensions that should be retained through the PCA step and the number of correlated signals. These approaches are based on reduced-rank versions of the Bartlett-Lawley hypothesis test and the minimum description length information-theoretic criterion. Simulation results show that the techniques perform well for very small sample sizes even in colored noise

Single-particle imaging reveals intraflagellar transport–independent transport and accumulation of EB1 in \u3cem\u3eChlamydomonas\u3c/em\u3e flagella

The microtubule (MT) plus-end tracking protein EB1 is present at the tips of cilia and flagella; end-binding protein 1 (EB1) remains at the tip during flagellar shortening and in the absence of intraflagellar transport (IFT), the predominant protein transport system in flagella. To investigate how EB1 accumulates at the flagellar tip, we used in vivo imaging of fluorescent protein–tagged EB1 (EB1-FP) in Chlamydomonas reinhardtii. After photobleaching, the EB1 signal at the flagellar tip recovered within minutes, indicating an exchange with unbleached EB1 entering the flagella from the cell body. EB1 moved independent of IFT trains, and EB1-FP recovery did not require the IFT pathway. Single-particle imaging showed that EB1-FP is highly mobile along the flagellar shaft and displays a markedly reduced mobility near the flagellar tip. Individual EB1-FP particles dwelled for several seconds near the flagellar tip, suggesting the presence of stable EB1 binding sites. In simulations, the two distinct phases of EB1 mobility are sufficient to explain its accumulation at the tip. We propose that proteins uniformly distributed throughout the cytoplasm like EB1 accumulate locally by diffusion and capture; IFT, in contrast, might be required to transport proteins against cellular concentration gradients into or out of cilia

The Genetic Algorithm: Using Biology to Compute Liquid Crystal Director Configurations

The genetic algorithm is an optimization routine for finding the solution to a problem that requires a function to be minimized. It accomplishes this by creating a population of solutions and then producing “offspring” solutions from this population by combining two “parental” solutions in much the way that the DNA of biological parents is combined in the DNA of offspring. Strengths of the algorithm include that it is simple to implement, no trial solution is required, and the results are fairly accurate. Weaknesses include its slow computational speed and its tendency to find a local minimum that does not represent the global minimum of the function. By minimizing the elastic, surface, and electric free energies, the genetic algorithm is used to compute the liquid crystal director configuration for a wide range of situations, including one- and two-dimensional problems with various forms of boundary conditions, with and without an applied electric field. When appropriate, comparisons are made with the exact solutions. Ways to increase the performance of the algorithm as well as how to avoid various pitfalls are discussed

Insights into How Vietnamese Retailers Utilize Social Media to Facilitate Knowledge Creation through the Process of Value Co-Creation

Social media usage is a direct result of Internet connectivity and is gaining increased prominence in business-to-consumer (B2C), business-to-business (B2B), and consumer-to-business (C2B) relationship building, which is allowing marketers to devise and implement digital marketing strategies that are perceived as enhancing a customer’s well-being. Through the process of utilizing social media (SM) to share information with consumers, marketers are affording themselves with the concept of value co-creation and ensuring that the development of knowledge is given priority. To explain how this happens in an emerging economy, in-depth personal interviews were undertaken with the owners of five retail fashion companies in Vietnam. The findings indicate that fashion retail companies in Vietnam are deploying digital marketing strategies that deliver perceived enhanced value to consumers through the process of value co-creation. This highlights the advantage of using SM in relation to increasing retail staff’s ability to convert information into usable resources such as intelligence and knowledge. By achieving knowledge conversion, retail staff fulfill the role of ‘knowledge broker’ and ‘knowledge connector’, and identify how organizational intervention, such as new operating structures, can help to deliver perceived enhanced value to customers