GRB 100418A: a Long GRB without a Bright Supernova in a High-Metallicity Host Galaxy

We present results of a search for a supernova (SN) component associated with GRB 100418A at the redshift of 0.624. The field of GRB 100418A was observed with FOCAS on Subaru 8.2m telescope under a photometric condition (seeing 0.3"-0.4") on 2010 May 14 (UT). The date corresponds to 25.6 days after the burst trigger (15.8 days in the restframe). We did imaging observations in V, Rc, and Ic bands, and two hours of spectrophotometric observations. We got the resolved host galaxy image which elongated 1.6" (= 11 kpc) from north to south. No point source was detected on the host galaxy. The time variation of Rc-band magnitude shows that the afterglow of GRB 100418A has faded to Rc \sim > 24 without SN like rebrightening, when we compare our measurement to the reports in GCN circulars. We could not identify any SN feature such as broad emission-lines or bumps in our spectrum. Assuming the SN is fainter than the 3{\sigma} noise spectrum of our observation, we estimate the upper limit on the SN absolute magnitude MIc,obs > -17.2 in observer frame Ic-band. This magnitude is comparable to the faintest type Ic SNe. We also estimate host galaxy properties from the spectrum. The host galaxy of GRB 100418A is relatively massive (log M_{star}/M_{sun} = 9.54) compared to typical long GRB host galaxies, and has 12+log(O/H) = 8.75.Comment: 8 pages, 8 figures, accepted for publication in PASJ, changed figure 8 and related tex

Deviance-related responses along the auditory hierarchy: combined FFR, MLR and MMN evidence

The mismatch negativity (MMN) provides a correlate of automatic auditory discrimination in human auditory cortex that is elicited in response to violation of any acoustic regularity. Recently, deviance-related responses were found at much earlier cortical processing stages as reflected by the middle latency response (MLR) of the auditory evoked potential, and even at the level of the auditory brainstem as reflected by the frequency following response (FFR). However, no study has reported deviance-related responses in the FFR, MLR and long latency response (LLR) concurrently in a single recording protocol. Amplitude-modulated (AM) sounds were presented to healthy human participants in a frequency oddball paradigm to investigate deviance-related responses along the auditory hierarchy in the ranges of FFR, MLR and LLR. AM frequency deviants modulated the FFR, the Na and Nb components of the MLR, and the LLR eliciting the MMN. These findings demonstrate that it is possible to elicit deviance-related responses at three different levels (FFR, MLR and LLR) in one single recording protocol, highlight the involvement of the whole auditory hierarchy in deviance detection and have implications for cognitive and clinical auditory neuroscience. Moreover, the present protocol provides a new research tool into clinical neuroscience so that the functional integrity of the auditory novelty system can now be tested as a whole in a range of clinical populations where the MMN was previously shown to be defectiv

The Star Formation Rate and Metallicity of the Host Galaxy of the Dark GRB 080325 at z=1.78

We present near-infrared spectroscopy of the host galaxy of the dark gamma-ray burst (GRB) 080325 using Subaru/Multi-Object Infrared Camera and Spectrograph. The obtained spectrum provides a clear detection of Hα emission and marginal [Nii]λ6584. The host is a massive (M_* ~ 10^(11) M_⊙), dusty (A_V ~ 1.2) star-forming galaxy at z = 1.78. The extinction-corrected star formation rate (SFR) calculated from the Hα luminosity (35.6–47.0 M_⊙ yr^(−1)) is typical among GRB host galaxies (and star-forming galaxies generally) at z>1; however, the specific SFR is lower than for normal star-forming galaxies at redshift ~1.6, in contrast to the high specific SFR measured for many of other GRB hosts. The metallicity of the host is estimated to be 12 + log(O/H)_(KK04) = 8.88. We emphasize that this is one of the most massive host galaxies at z>1 for which metallicity is measured with emission-line diagnostics. The metallicity is fairly high among GRB hosts, however, this is still lower than the metallicity of normal star-forming galaxies of the same mass at z ~ 1.6. The metallicity offset from normal star-forming galaxies is close to a typical value of other GRB hosts and indicates that GRB host galaxies are uniformly biased toward low metallicity over a wide range of redshifts and stellar masses. The low-metallicity nature of the GRB 080325 host likely cannot be attributed to the fundamental metallicity relation of star-forming galaxies because it is a metal-poor outlier from the relation and has a low specific star formation rate. Thus, we conclude that metallicity is important to the mechanism that produced this GRB

Parental Recognition of Bullying and Associated Factors Among Children After the Fukushima Nuclear Disaster: A 3-Year Follow-Up Study From the Fukushima Health Management Survey

This study examined parental recognition of bullying victimization and associated factors among evacuated children after the 2011 Fukushima Daiichi Nuclear Power Plant accident, using a 3-year follow-up data (wave 1: January 2012; wave 2: January 2013; wave 3: February 2014). The sample included the caregivers of 2,616 children in the first–sixth grades of elementary school, who lived in one of the 13 municipalities that were the target areas of the Mental Health and Lifestyle Survey, conducted as part of the Fukushima Mental Health Management Survey. Across 3 years, around 80% of caregivers responded “not true,” 15% responded “somewhat true,” and 5% responded “certainly true” in response to a question about bullying victimization of their children. Being male was significantly associated with the parental recognition of bullying victimization at wave 1 and wave 3. At wave 1, experiencing the nuclear plant explosion was significantly associated with parental recognition of bullying victimization. Moreover, age at wave 3 was negatively associated with parental recognition of bullying victimization. Our findings will be helpful for establishing community- and school-based mental health care for children, parents, and teachers

Socioeconomic status, damage-related conditions, and PTSD following the Fukushima-daiichi nuclear power plant accident:The Fukushima Health Management Survey

The Great East Japan Earthquake severely damaged the Tohoku and Kanto districts, and Fukushima Prefecture faced a subsequent nuclear disaster. Few studies have reported the effects of socioeconomic stressors on individuals' mental status following disasters. We analyzed the responses of 60,704 adult residents of a designated restricted area to the PTSD Checklist-Stressor-Specific Version (PCL-S). The relationships between the PCL-S scores and demographic, socioeconomic, and damage-related variables were analyzed using regression analysis to predict participants' severity of PTSD symptoms. Approximately 14.1% of evacuees had severe PTSD symptoms (PCL-S ≥50) eighteen months post-earthquake. The PCL-S scores were higher among women, older adults, less educated people, those with a history of mental illness, and those living outside Fukushima Prefecture. The PCL-S scores increased with participants' scores on the Kessler Psychological Distress Scale. The number of trauma-exposure stressors and socioeconomic stressors were associated with 1.52 and 3.77 increases in the PCL-S score, respectively. Furthermore, psychological distress, unemployment, decreased income, house damage, tsunami experience, nuclear power plant accident experience, and loss of someone close due to the disaster were associated with the prevalence of severe PTSD symptoms. The complex triple disaster of a major earthquake, tsunami, and nuclear accident created significant socioeconomic changes that may be important determinants of PTSD among residents of restricted access areas in Fukushima

Dietary pattern changes in Fukushima residents after the Great East Japan Earthquake: the Fukushima Health Management Survey 2011-2013

Objective: Dietary patterns more closely resemble actual eating behaviours because multiple food groups, not a single food group or nutrient, are considered. The present study aimed to identify and assess changes of dietary patterns in Fukushima residents. Design: Dietary data were collected using a short-form FFQ in annual Fukushima Health Management Survey between 2011 and 2013 after the Great East Japan Earthquake. Year- and sex-specific dietary patterns were determined by the principal component analysis. Setting: Evacuation and nonevacuation zones in Fukushima, Japan. Participants: Eligible participants aged ≥16 years answered the FFQ (n 67 358 in 2011, n 48 377 in 2012 and n 40 742 in 2013). Results: Three identified dietary patterns were assessed similarly in men and women and among years: typical, juice and meat. In total participants, the Spearman's correlation coefficients between two survey years were 0·70-0·74 for the typical, 0·58-0·66 for the juice and 0·50-0·54 for the meat pattern scores. Adjusted for sociodemographic factors, evacuees had lower typical pattern scores, higher juice pattern scores and the same meat pattern scores compared with non-evacuees. The means of typical pattern scores in evacuees and it of juice pattern scores in non-evacuees continued declining over years. Similar profiles of dietary patterns and trends of pattern scores were observed in participants (n 22 805) who had provided three dietary assessments. Conclusions: Changes of dietary patterns have been observed between 2011 and 2013. Careful investigation of those with low intake of typical pattern foods and promotion of them, particularly in evacuees, are needed

From Hiroshima and Nagasaki to Fukushima 2: Health effects of radiation and other health problems in the aftermath of nuclear accidents, with an emphasis on Fukushima

437 nuclear power plants are in operation at present around the world to meet increasing energy demands. Unfortunately, five major nuclear accidents have occurred in the past--ie, at Kyshtym (Russia [then USSR], 1957), Windscale Piles (UK, 1957), Three Mile Island (USA, 1979), Chernobyl (Ukraine [then USSR], 1986), and Fukushima (Japan, 2011). The effects of these accidents on individuals and societies are diverse and enduring. Accumulated evidence about radiation health effects on atomic bomb survivors and other radiation-exposed people has formed the basis for national and international regulations about radiation protection. However, past experiences suggest that common issues were not necessarily physical health problems directly attributable to radiation exposure, but rather psychological and social effects. Additionally, evacuation and long-term displacement created severe health-care problems for the most vulnerable people, such as hospital inpatients and elderly people

Changes in drinking behavior among evacuees after the Fukushima Daiichi Nuclear Power Plant accident:the Fukushima Health Management Survey

Introduction Traumatic experiences and disordered sleep are strongly associated with drinking problems. We examined the effects of experiencing the Great East Japan Earthquake and subsequent nuclear power plant accident, and of sleep problems, on behavioral changes observed in non-drinkers.Methods This study examined cross-sectional data from the Mental Health and Lifestyle Survey conducted among residents in restricted areas of Fukushima in 2012. Participants were 21,454 evacuees aged 20 years or older at the time of disaster. People who did not drink before the disaster but became drinkers afterwards were compared with the rest of the cohort. We analyzed the association between behavioral changes in non-drinkers and potentially predictive variables, using logistic regression.Results The behavioral change of non-drinkers becoming drinkers (n=2,148) was significantly related to being male (OR=1.93, 95% CI:1.74-2.15), being younger (21-49 yrs, OR=1.85, 95% CI: 1.60-2.13), having less educational attainment (up to high school graduate, OR=1.21, 95% CI:1.09-1.35), smoking (OR=1.22, 95% CI:1.08-1.38), losing family or relatives (OR=1.21, 95% CI:1.07-1.37), change in employment (OR=1.19, 95% CI:1.07-1.32), having severe sleep problems as measured by a Japanese version of the Athens Insomnia Scale (3-8, OR=1.45, 95% CI:1.30-1.62), and severity of traumatic symptoms as measured by the PTSD Checklist Stressor-Specific (PCL-S) score (<44, OR=1.33, 95% CI:1.17-1.51).Conclusion Having sleep problems and having more severe traumatic symptoms are significantly related to non-drinkers becoming drinkers