Information‐Theoretic Clustering and Algorithms

Clustering is the task of partitioning objects into clusters on the basis of certain criteria so that objects in the same cluster are similar. Many clustering methods have been proposed in a number of decades. Since clustering results depend on criteria and algorithms, appropriate selection of them is an essential problem. Recently, large sets of users’ behavior logs and text documents are common. These are often presented as high‐dimensional and sparse vectors. This chapter introduces information‐theoretic clustering (ITC), which is appropriate and useful to analyze such a high‐dimensional data, from both theoretical and experimental side. Theoretically, the criterion, generative models, and novel algorithms are shown. Experimentally, it shows the effectiveness and usefulness of ITC for text analysis as an important example

Analysis of Solution Diversity in Topic Models for Smart City Applications

Topic models are known to be useful tools for modeling and analyzing high-dimensional count data such as documents. In a smart city, it is important to collect and analyze citizens’ voices to discover their concerns and issues. Topic modeling is effective for the above analysis because it can extract topics from a collection of documents. However, when estimating parameters (solutions) in topic models, various solutions are reached due to differences in algorithms and initial values. In order to select a solution suitable for the purpose from among the various solutions, it is necessary to know what kind of solutions exist. This chapter introduces methods for analyzing diverse solutions and obtaining an overall picture of the solutions

Signaling emotion in tagclouds

ABSTRACT In order to create more attractive tagclouds that get people interested in tagged content, we propose a simple but novel tagcloud where font size is determined by tag's entropy value, not the popularity to its content. Our method raises users' emotional interest in the content by emphasizing more emotional tags. Our initial experiments show that emotional tagclouds attract more attention than normal tagclouds at first look; thus they will enhance the role of tagcloud as a social signaller

The CD70-CD27 interaction during the stimulation with dendritic cells promotes naive CD4+ T cells to develop into T cells producing a broad array of immunostimulatory cytokines in humans

CD70 expressed on dendritic cells (DCs) has been shown to play a critical role in inducing effective CD8+ T cell responses and a Th1 response in mice. However, it has not been extensively examined whether human primary DCs express CD70 and whether the CD70–CD27 interaction promotes naive CD4+ T cells to acquire the ability to produce effector cytokines during the DC–T cell interaction in humans. Here, we show that human myeloid dendritic cells (mDCs) and plasmacytoid dendritic cells stimulated with CD40 ligand together with pro-inflammatory cytokines or Toll-like receptor ligands express CD70. Thymic stromal lymphopoietin plus prostaglandin E2 also induced CD70 on mDCs. Naive CD4+ T cells stimulated with DCs but not with anti-CD3/CD28 microbeads expressed CD70. Stimulation with CD70 together with anti-CD3/CD28 microbeads imparted the ability to produce Th1 (IFN-), Th2 (IL-4, IL-5, IL-13) cytokines, IL-2 and tumor necrosis factor- to naive CD4+ T cells. The production of IFN- was associated with the induction of T-bet. Naive CD4+ T cells stimulated with mDCs acquired an enhanced ability to produce a broad array of immunostimulatory cytokines in a CD70-dependent manner. These data suggest that human CD70 expressed on mDCs and activated T cells transmits a ‘basal level’ signal, rather than a ‘polarizing’ signal, to naive CD4+ T cells, in that CD70 promotes the development of CD4+ T cells that produce a variety of effector cytokines including both Th1 and Th2 types, thus contributing to the enhancement of a broad spectrum of immune responses

High Resolution Field Emission Spectra from Niobium (100) Tip Surface(APFIM/FIM)

We have developed a new apparatus to measure the energy spectra of field emission electrons with the high resolution. By using the apparatus, we have measured the high-resolution spectra of the electrons emitted from the Nb(100) tip at liquid-nitrogen temperature and detected the electronic surface (sub-surface) resonance states and the atomic vibrations of chemisorbed hydrogen

Impurity-Induced Antiferromagnetic Ordering in the Spin Gap System TlCuCl_3

The magnetization measurements have been performed on the doped spin gap system TlCu_{1-x}Mg_xCl_3 with x <= 0.025. The parent compound TlCuCl_3 is a three-dimensional coupled spin dimer system with the excitation gap Delta/k_B = 7.7 K. The impurity-induced antiferromagnetic ordering was clearly observed. The easy axis lies in the (0,1,0) plane. It was found that the transition temperature increases with increasing Mg^{2+} concentration x, while the spin-flop transition field is almost independent of x. The magnetization curve suggests that the impurity-induced antiferromagnetic ordering coexists with the spin gap for x <= 0.017.Comment: 5 pages, 6 figures, revtex styl

Butyrate and bioactive proteolytic form of Wnt-5a regulate colonic epithelial proliferation and spatial development

Proliferation and spatial development of colonic epithelial cells are highly regulated along the crypt vertical axis, which, when perturbed, can result in aberrant growth and carcinogenesis. In this study, two key factors were identified that have important and counterbalancing roles regulating these processes: pericrypt myofibroblast-derived Wnt-5a and the microbial metabolite butyrate. Cultured YAMC cell proliferation and heat shock protein induction were analzyed after butryate, conditioned medium with Wnt5a activity, and FrzB containing conditioned medium. In vivo studies to modulate Hsp25 employed intra-colonic wall Hsp25 encoding lentivirus. To silence Wnt-5a in vivo, intra-colonic wall Wnt-5a silencing RNA was used. Wnt-5a, secreted by stromal myofibroblasts of the lower crypt, promotes proliferation through canonical β-catenin activation. Essential to this are two key requirements: (1) proteolytic conversion of the highly insoluble ~40 kD Wnt-5a protein to a soluble 36 mer amino acid peptide that activates epithelial β-catenin and cellular proliferation, and (2) the simultaneous inhibition of butyrate-induced Hsp25 by Wnt-5a which is necessary to arrest the proliferative process in the upper colonic crypt. The interplay and spatial gradients of these factors insures that crypt epithelial cell proliferation and development proceed in an orderly fashion, but with sufficient plasticity to adapt to physiological perturbations including inflammation

The Effect of Surgical Repair for Pectum Excavatum on Cardiopulmonary Function

In five patients with corrective surgery for pectus Excavatum, the effectiveness of surgical repair were evaluated from the results of pulmonary function test as well as the finding on ECG according to follow-up study postoperativelly. Of five patient undergone the corrective surgery which sternoturnover with costalplasty employed in 4, and sternoplasty alone in I, all of them were male and the average age except 3 years of age was 14.8 years ranging from 10 to 21 years. There are no manifestation of clinical syndrome in all 5 cases. However, the fair mental growth demands psychologically the early corrective surgery in young chidren. By follow-up study after surgical correction for pectus excavatum during a period from 3 months to 3 years and 3 months, the finding on EKG of right ventricular overload revealed the improvement within 2 months after surgical correction in contrast the results of pulmonary function test disclosed no marked changes until 2 months following surgery. From the view of cosmetic efficacy of corrective surgery, sternoturnover with or without costalplasty are one of the adovocating operative procedures