Majorana bound state of a Bogoliubov-de Gennes-Dirac Hamiltonian in arbitrary dimensions

We study a Majorana zero-energy state bound to a hedgehog-like point defect in a topological superconductor described by a Bogoliubov-de Gennes (BdG)-Dirac type effective Hamiltonian. We first give an explicit wave function of a Majorana state by solving the BdG equation directly, from which an analytical index can be obtained. Next, by calculating the corresponding topological index, we show a precise equivalence between both indices to confirm the index theorem. Finally, we apply this observation to reexamine the role of another topological invariant, i.e., the Chern number associated with the Berry curvature proposed in the study of protected zero modes along the lines of topological classification of insulators and superconductors. We show that the Chern number is equivalent to the topological index, implying that it indeed reflects the number of zero-energy states. Our theoretical model belongs to the BDI class from the viewpoint of symmetry, whereas the spatial dimension of the system is left arbitrary throughout the paper.Comment: 12 page

Are Maternal Social Networks and Perceptions of Trust Associated with Suspected Autism Spectrum Disorder in Offspring? A Population-Based Study in Japan

Objective: To investigate the associations of maternal social networks and perceptions of trust with the prevalence of suspected autism spectrum disorders in 18-month-old offspring in Japan. Methods: Questionnaires included measurements of maternal social networks (number of relatives or friends they could call upon for assistance), maternal perceptions of trust, mutual assistance (i.e. individual measures of “cognitive social capital”), and social participation (i.e. individual measures of “structural social capital”) as well as the Modified Checklist for Autism in Toddlers to detect suspected autism spectrum disorder (ASD). These tools were mailed to all families with 18-month-old toddlers in Chiba, a city near Tokyo (N = 6061; response rate: 64%). The association between social capital or social network indicators and suspected ASD were analyzed, adjusted for covariates by logistic regression analysis. Results: Low maternal social trust was found to be significantly positively associated with suspected ASD in toddlers compared with high maternal social trust (adjusted odds ratio [OR]: 1.82, 95% confidence interval [CI]: 1.38 to 2.40); mutual aid was also significantly positively related (low vs. high: OR, 1.82, 95% CI: 1.38 to 2.40). However, maternal community participation showed U-shape association with suspected ASD of offspring. Maternal social network showed consistent inverse associations with suspected ASD of offspring, regardless of the type of social connection (e.g., relatives, neighbors, or friends living outside of their neighborhood). Conclusions: Mothers' cognitive social capital and social networks, but not structural social capital, might be associated with suspected ASD in offspring

Social Capital and Health: A Review of Prospective Multilevel Studies

Background: This article presents an overview of the concept of social capital, reviews prospective multilevel analytic studies of the association between social capital and health, and discusses intervention strategies that enhance social capital. Methods: We conducted a systematic search of published peer-reviewed literature on the PubMed database and categorized studies according to health outcome. Results: We identified 13 articles that satisfied the inclusion criteria for the review. In general, both individual social capital and area/workplace social capital had positive effects on health outcomes, regardless of study design, setting, follow-up period, or type of health outcome. Prospective studies that used a multilevel approach were mainly conducted in Western countries. Although we identified some cross-sectional multilevel studies that were conducted in Asian countries, including Japan, no prospective studies have been conducted in Asia. Conclusions: Prospective evidence from multilevel analytic studies of the effect of social capital on health is very limited at present. If epidemiologic findings on the association between social capital and health are to be put to practical use, we must gather additional evidence and explore the feasibility of interventions that build social capital as a means of promoting health

Therapeutic effect of hyperthermia combined with chemotherapy on vulvar and vaginal carcinoma.

A clinical trial was performed to investigate the efficacy of hyperthermia in combination with chemotherapy for gynecological malignancies. Sixty-nine patients with vaginal or vulvar malignancies (9 primary vulvar, 3 recurrent vulvar, 11 primary vaginal, 4 primary cervical, 40 recurrent cervical, and 2 recurrent ovarian carcinomas) were treated by thermochemotherapy (42 cases) or chemotherapy alone (27 cases). After treatment, 7 patients underwent surgery and 46 patients irradiation. The chemotherapeutic schedule was mainly a combination therapy with bleomycin and mitomycin C (B-M). Microwaves of 2.45 GHz were applied to induce local hyperthermia. The side effects of chemotherapy were not increased by hyperthermia. The rate of partial response plus complete response increased to 84% (16/19) in primary cancers and 45% in recurrent cancers by hyperthermia, compared to the respective values of 40% (2/5) and 17% (3/17) for chemotherapy alone. However, a satisfactory prognosis cannot be expected with thermochemotherapy, unless additional treatments are performed. Subsequent surgery or radiation treatment improved the progression-free interval.</p

Subjective social status and trajectories of self-rated health status: a comparative analysis of Japan and the United States

[Background] Japanese society is more egalitarian than the United States as is reflected by the lower degree of prevalence of social inequalities in health. We examined whether subjective socioeconomic status is associated with different trajectories of self-rated health (SRH), and whether this relationship differs between the United States and Japan. [Methods] We analyzed the responses of 3968 Americans from the survey Midlife in the United States, 2004–06, and the responses of 989 Japanese from the survey Midlife in Japan, 2008. We conducted a multilevel analysis with three self-ratings of health (10 years ago, current and 10 years in the future) nested within individuals and nested within 10 levels of subjective social status. Age, sex, educational level and subjective financial situation were adjusted. [Results] After making statistical adjustments for confounding variables, respondents in Japan continued to report lower average levels of health. However, the rate of expected decline in SRH over the next decade was strongly socially patterned in the United States, whereas it was not in Japan. [Conclusion] The Japanese showed no disparity in the anticipated trajectory of SRH over time, whereas the Americans showed a strong social class gradient in future trajectories of SRH

The Association between Oxytocin and Social Capital

Background: Oxytocin is known to be related to social behaviors, including trust. However, few studies have investigated the association between oxytocin levels and social capital. Thus, we tested the hypothesis that endogenous oxytocin levels are positively associated with social capital. We also considered whether the association differed across gender because previous studies have shown differential effects of OT on social behaviors depending on gender. Methods: We recruited a convenience sample of 50 women and 31 men in Japan via community sampling from whom we obtained urine sample with which to measure oxytocin levels. Individual-level cognitive social capital (social trust and mutual aid) and structural social capital (community participation) were assessed using a questionnaire. We used multivariate regression, adjusted for covariates (age, number of children, self-rated health, and education), and stratified by gender to consider associations between oxytocin and social capital. Results: Among women, oxytocin was inversely associated with social trust and mutual aid (p<0.05). However, women participating in only 1 organization in the community showed higher oxytocin than women who participated in either no organizations (p<0.05) or 2 or more organization (i.e. inverse-U shape association). Among men, no association was observed between oxytocin and either form of cognitive and structural social capital. Conclusion: Women who perceived low cognitive social capital showed higher oxytocin levels, while structural social capital showed inverse-U shape association with oxytocin. No association between oxytocin and social capital was found among men. Further study is needed to elucidate why oxytocin was inversely associated with cognitive social capital only among women

Faint warm debris disks around nearby bright stars explored by AKARI and IRSF

Context: Debris disks are important observational clues for understanding planetary-system formation process. In particular, faint warm debris disks may be related to late planet formation near 1 AU. A systematic search of faint warm debris disks is necessary to reveal terrestrial planet formation. Aims: Faint warm debris disks show excess emission that peaks at mid-IR wavelengths. Thus we explore debris disks using the AKARI mid-IR all-sky point source catalog (PSC), a product of the second generation unbiased IR all-sky survey. Methods : We investigate IR excess emission for 678 isolated main-sequence stars for which there are 18 micron detections in the AKARI mid-IR all-sky catalog by comparing their fluxes with the predicted fluxes of the photospheres based on optical to near-IR fluxes and model spectra. The near-IR fluxes are first taken from the 2MASS PSC. However, 286 stars with Ks<4.5 in our sample have large flux errors in the 2MASS photometry due to saturation. Thus we have measured accurate J, H, and Ks band fluxes, applying neutral density (ND) filters for Simultaneous InfraRed Imager for Unbiased Survey (SIRIUS) on IRSF, the \phi 1.4 m near-IR telescope in South Africa, and improved the flux accuracy from 14% to 1.8% on average. Results: We identified 53 debris-disk candidates including eight new detections from our sample of 678 main-sequence stars. The detection rate of debris disks for this work is ~8%, which is comparable with those in previous works by Spitzer and Herschel. Conclusion: The importance of this study is the detection of faint warm debris disks around nearby field stars. At least nine objects have a large amount of dust for their ages, which cannot be explained by the conventional steady-state collisional cascade model.Comment: 17 pages, 21 figures, accepted for publication in Astronomy and Astrophysic