D4 Flavor Symmetry for Neutrino Masses and Mixing

We present the $D_4\times Z_2$ flavor symmetry, which is different from the previous work by Grimus and Lavoura. Our model reduces to the standard model in the low energy and there is no FCNC at the tree level. Putting the experimental data, parameters are fixed, and then the implication of our model is discussed. The condition to realize the tri-bimaximal mixing is presented. The possibility for stringy realization of our model is also discussed.Comment: 10 pages, 1 figur

Constraints on Finite Soft Supersymmetry-Breaking Terms

Requiring the soft supersymmetry-breaking (SSB) parameters in finite gauge-Yukawa unified models to be finite up to and including two-loop order, we derive a two-loop sum rule for the soft scalar-masses. It is shown that this sum rule coincides with that of a certain class of string models in which the massive string states are organized into N=4 supermultiplets. We investigate the SSB sector of two finite SU(5) models. Using the sum rule which allows the non-universality of the SSB terms and requiring that the lightest superparticle particleis neutral, we constrain the parameter space of the SSB sector in each model.Comment: 34 page

Influence of subretinal fluid in advanced stage retinopathy of prematurity on proangiogenic response and cell proliferation

Purpose The clinical phenotype of advanced stage retinopathy of prematurity (ROP, stages 4 and 5) cannot be replicated in an animal model. To dissect the molecular events that can lead up to advanced ROP, we examined subretinal fluid (SRF) and surgically dissected retrolental membranes from patients with advanced ROP to evaluate its influences on cell proliferation, angiogenic properties, and macrophage polarity. Methods: We compared our findings to SRF collected from patients with uncomplicated rhegmatogenous retinal detachment (RD) without proliferative vitreoretinopathy and surgically dissected epiretinal membrane from eyes with macular pucker. All subretinal fluid samples were equalized for protein. The angiogenic potential of SRF from ROP eyes was measured using a combination of capillary cord formation in a fibrin clot assay, and its proliferative effect was tested with a DNA synthesis of human retinal microvascular endothelial cells. Findings were compared with SRF collected from participants with uncomplicated rhegmatogenous RD without proliferative vitreoretinopathy. The ability of SRF to induce nitric oxide production was measured in vitro using murine J774A.1 macrophages. Cytokine profiles of SRF from ROP and RD eyes were measured using a multienzyme-linked immunosorbent assay (ELISA). Fluorescent immunohistochemistry of retrolental membranes from ROP was performed to detect the presence of leukocytes and the composition of tissue macrophages using markers for M1 and M2 differentiation. Results: The cytokine composition in SRF revealed that in ROP, not only were several proangiogenic factors were preferentially elevated but also the profile of proinflammatory factors was also increased compared to the RD eyes. SRF from ROP eyes supported cell proliferation and endothelial cord formation while SRF from RD eyes had inhibitory effects. SRF from eyes with ROP but not RD robustly induced nitric oxide production in macrophages. Furthermore, fluorescent immunostaining revealed a preponderance of M1 over M2 macrophages in retrolental fibrous membranes from ROP eyes. The cytokine profile and biologic properties of SRF in ROP promote a proangiogenic environment, which supports the maintenance and proliferation of fibrous membranes associated with advanced stages of ROP. In contrast, SRF from RD eyes exhibits a suppressive environment for endothelial cell proliferation and angiogenesis. Conclusions: Our investigation demonstrates that the microenvironment in advanced ROP eyes is proangiogenic and proinflammatory. These findings suggest that management of advanced ROP should not be limited to the surgical removal of the fibrovascular membranes and antiangiogenic therapy but also directed to anti-inflammatory therapy and to promote M2 activation over M1 activity

Towards Minimal S4 Lepton Flavor Model

We study lepton flavor models with the $S_4$ flavor symmetry. We construct simple models with smaller numbers of flavon fields and free parameters, such that we have predictions among lepton masses and mixing angles. The model with a $S_4$ triplet flavon is not realistic, but we can construct realistic models with two triplet flavons, or one triplet and one doublet flavons.Comment: 18 pages, 4 figures, references are adde

Stringy origin of non-Abelian discrete flavor symmetries

We study the origin of non-Abelian discrete flavor symmetries in superstring theory. We classify all possible non-Abelian discrete flavor symmetries which can appear in heterotic orbifold models. These symmetries include D_4 and Delta(54). We find that the symmetries of the couplings are always larger than the symmetries of the compact space. This is because they are a consequence of the geometry of the orbifold combined with the space group selection rules of the string. We also study possible breaking patterns. Our analysis yields a simple geometric understanding of the realization of non-Abelian flavor symmetries.Comment: 27 pages, 4 figures, v2: matches version published in Nuclear Physics

Hepatic STAT1-Nuclear Translocation and Interleukin 28B Polymorphisms Predict Treatment Outcomes in Hepatitis C Virus Genotype 1-Infected Patients

We investigated associations between signal transducer and activator of transcription (STAT) 1 in pretreated liver tissues, interleukin (IL) 28B polymorphism and treatment response in hepatitis C virus (HCV)-infected patients treated with peginterferon and ribavirin.We performed immunostaining analysis of STAT1 in liver tissues and determined IL28B polymorphism at rs8099917. We then compared the results with treatment outcomes in HCV genotype 1 patients with high viral load who were receiving peginterferon plus ribavirin. In univariate analysis, younger age, white blood cell counts, virological responder, early virological responder (EVR), mild activity (A1) of liver inflammation grading, and lower STAT1 nuclear-stain of hepatocytes in zone 1, zone 2 and total zones of liver were associated with sustained virological responder (SVR). Multivariate analysis showed that EVR, age and hepatic STAT1 nuclear-stain in zone 2 of liver were independent predictors of SVR. It was also revealed that IL28B and STAT1-nuclear translocation in hepatocytes are independent predictors of response to treatment with peginterferon and ribavirin in chronic hepatitis C patients.Concomitant assessment of lower STAT1 nuclear-stain of hepatocytes and IL28B polymorphism is useful for prediction of SVR in HCV genotype 1 patients

Non-Abelian Discrete Flavor Symmetries from Magnetized/Intersecting Brane Models

We study non-abelian discrete flavor symmetries, which can appear in magnetized brane models. For example, $D_4$, $\Delta(27)$ and $\Delta(54)$ can appear and matter fields with several representations can appear. We also study the orbifold background, where non-abelian flavor symmetries are broken in a certain way.Comment: 20 page

Finite Theories and the SUSY Flavor Problem

We study a finite SU(5) grand unified model based on the non-Abelian discrete symmetry A_4. This model leads to the democratic structure of the mass matrices for the quarks and leptons. In the soft supersymmetry breaking sector, the scalar trilinear couplings are aligned and the soft scalar masses are degenerate, thus solving the SUSY flavor problem.Comment: 17 pages, LaTeX, 1 figur