Music-experience-related and musical-error-dependent activations in the brain.

Although music is one of human-unique traits such as language, its neural basis for cortical organization has not been well understood. In the present functional magnetic resonance imaging study, we tested an error-detection task with different types of musical error (pitch, tempo, stress, and articulation conditions) and examined three groups of secondary school students having different levels of music experience. First, we observed distinct activation patterns under these music conditions, such that specific activations under the pitch condition were consistently replicated for all tested groups in the auditory areas, as well as in the left language areas under the articulation condition. Second, music-experience-related activations were observed in multiple regions, including the right sensorimotor area under the pitch condition, as well as in the right premotor cortex under the articulation condition. Indeed, the right homologs of the language areas were specifically activated under the stress and articulation conditions. Third, activations specific to the group with the highest proficiency in music were observed under the tempo condition mostly in the right regions. These results demonstrate the existence of music-related signatures in the brain activations, including both universal and experience-related mechanisms.

Comparison of the UNSCEAR isodose maps for annual external exposure in Fukushima with those obtained based on airborne monitoring surveys.

In 2016, UNSCEAR published an attachment to its Fukushima 2015 White Paper, entitled 'Development of isodose maps representing annual external exposure in Japan as a function of time', in which the committee presented an annual additional 1 mSv effective dose ab extra isodose lines for 1, 3, 5, 10, 30, 50 years after the accident, based on the soil deposition data of radionuclides within 100 km of the Fukushima Dai-ichi Nuclear Power Plant. Meanwhile, the median of the ratio, c, between the external effective dose rates and the ambient dose equivalent rates 1 m above the ground obtained by airborne monitoring has been established to be [Formula: see text]. Here, we compare the UNSCEAR predictions with estimates based on the airborne monitoring. Although both the methods and the data used in the two approaches are different, the resultant contours show relatively good agreement. However, to improve the accuracy of long-term annual effective isodose lines, feedback from continuous measurements such as airborne monitoring is important.

Two-photon laser spectroscopy of antiprotonic helium and the antiproton-to-electron mass ratio.

Physical laws are believed to be invariant under the combined transformations of charge, parity and time reversal (CPT symmetry). This implies that an antimatter particle has exactly the same mass and absolute value of charge as its particle counterpart. Metastable antiprotonic helium (pHe(+)) is a three-body atom consisting of a normal helium nucleus, an electron in its ground state and an antiproton (p) occupying a Rydberg state with high principal and angular momentum quantum numbers, respectively n and l, such that n ≈ l + 1 ≈ 38. These atoms are amenable to precision laser spectroscopy, the results of which can in principle be used to determine the antiproton-to-electron mass ratio and to constrain the equality between the antiproton and proton charges and masses. Here we report two-photon spectroscopy of antiprotonic helium, in which p(3)He(+) and p(4)He(+) isotopes are irradiated by two counter-propagating laser beams. This excites nonlinear, two-photon transitions of the antiproton of the type (n, l) → (n - 2, l - 2) at deep-ultraviolet wavelengths (λ = 139.8, 193.0 and 197.0 nm), which partly cancel the Doppler broadening of the laser resonance caused by the thermal motion of the atoms. The resulting narrow spectral lines allowed us to measure three transition frequencies with fractional precisions of 2.3-5 parts in 10(9). By comparing the results with three-body quantum electrodynamics calculations, we derived an antiproton-to-electron mass ratio of 1,836.1526736(23), where the parenthetical error represents one standard deviation. This agrees with the proton-to-electron value known to a similar precision.

Individual external dose monitoring of all citizens of Date City by passive dosimeter 5 to 51 months after the Fukushima NPP accident (series): II. Prediction of lifetime additional effective dose and evaluating the effect of decontamination on individual dose.

In the first paper of this series, we showed that the ratio c of individual dose to ambient dose did not change with time in Date City, Fukushima Prefecture, after the Fukushima Daiichi Nuclear Power Plant accident. The purpose of the present paper, the second in a series, is to estimate the lifetime doses of the Date City residents, based on continuous glass badge monitoring data, extrapolated by means of the ambient-dose-rate reduction function obtained from the airborne monitoring data. As a result, we found that the external exposure contribution to the mean additional lifetime dose of residents living in Date City is not expected to exceed 18 mSv. In addition, effects of decontamination on the reduction of individual doses were not evident. This method of combining individual doses and the ambient doses, as developed in this study, has made it possible to predict with reasonable certainty the lifetime doses of residents who continue to live in this radiologically contaminated area.

Individual external dose monitoring of all citizens of Date City by passive dosimeter 5 to 51 months after the Fukushima NPP accident (series): 1. Comparison of individual dose with ambient dose rate monitored by aircraft surveys.

Date (da'te) City in Fukushima Prefecture has conducted a population-wide individual dose monitoring program after the Fukushima Daiichi Nuclear Power Plant Accident, which provides a unique and comprehensive data set of the individual doses of citizens. The purpose of this paper, the first in the series, is to establish a method for estimating effective doses based on the available ambient dose rate survey data. We thus examined the relationship between the individual external doses and the corresponding ambient doses assessed from airborne surveys. The results show that the individual doses were about 0.15 times the ambient doses, the coefficient of 0.15 being a factor of 4 smaller than the value employed by the Japanese government, throughout the period of the airborne surveys used. The method obtained in this study could aid in the prediction of individual doses in the early phase of future radiological accidents involving large-scale contamination.

Comparison between direct measurements and modeled estimates of external radiation exposure among school children 18 to 30 months after the Fukushima nuclear accident in Japan.

After a major radioactive incident, accurate dose reconstruction is important for evaluating health risks and appropriate radiation protection policies. After the 2011 Japan Fukushima nuclear incident, we assessed the level of agreement between the modeled and directly measured dose and estimated the uncertainties. The study population comprised 520 school children from Minamisoma city, located 20 km north of the nuclear plant. The annual dose 18­30 months after the incident was assessed using two approaches: estimation using the model proposed by the Japanese government and direct measurement by radiation dosemeters. The ratio of the average of modeled and measured doses was 3.0 (standard deviation (SD): 2.0). The reduction coefficient, an index for radiation attenuation properties, was 0.3 (SD: 0.1) on average, whereas the value used in the government model was 0.6. After adjusting for covariates, the coefficient had a significant negative correlation with the air dose rate in the dwelling location (p < 0.001), indicating that stronger building shielding effects are valuable in areas with higher air contamination levels. The present study demonstrated that some overestimation may have been related to uncertainties in radiation reduction effects, and that the air contamination level might provide a more important indicator of these effects.

Whole-body counter surveys of Miharu-town school children for four consecutive years after the Fukushima NPP accident.

Comprehensive whole-body counter surveys of Miharu-town school children have been conducted for four consecutive years, in 2011-2014. This represents the only long-term sampling-bias-free study of its type conducted after the Fukushima Dai-ichi accident. For the first time in 2014, a new device called the Babyscan, which has a low (134/137)Cs MDA of <50 Bq/body, was used to screen the children shorter than 130 cm. No child in this group was found to have detectable level of radiocesium. Using the MDAs, upper limits of daily intake of radiocesium were estimated for each child. For those screened with the Babyscan, the upper intake limits were found to be ≲1 Bq/day for (137)Cs. Analysis of a questionnaire filled out by the children's parents regarding their food and water consumption shows that the majority of Miharu children regularly consume local and/or home-grown rice and vegetables. This however does not increase the body burden.

Whole-body counter surveys of over 2700 babies and small children in and around Fukushima Prefecture 33 to 49 months after the Fukushima Daiichi NPP accident.

BABYSCAN, a whole-body counter (WBC) for small children was developed in 2013, and units have been installed at three hospitals in Fukushima Prefecture. Between December, 2013 and March, 2015, 2707 children between the ages of 0 and 11 have been scanned, and none had detectable levels of radioactive cesium. The minimum detectable activities (MDAs) for (137)Cs were ≤ 3.5 Bq kg(-1) for ages 0-1, decreasing to ≤ 2 Bq kg(-1) for ages 10-11. Including the (134)Cs contribution, these translate to a maximum committed effective dose of ∼ 16 µSv y(-1) even for newborn babies, and therefore the internal exposure risks can be considered negligibly small.Analysis of the questionnaire filled out by the parents of the scanned children regarding their families' food and water consumption revealed that the majority of children residing in the town of Miharu regularly consume local or home-grown rice and vegetables, while in Minamisoma, a majority avoid tap water and produce from Fukushima. The data show, however, no correlation between consumption of locally produced food and water and the children's body burdens.

Cesium-137 deposition and contamination of Japanese soils due to the Fukushima nuclear accident.

The largest concern on the cesium-137 ((137)Cs) deposition and its soil contamination due to the emission from the Fukushima Daiichi Nuclear Power Plant (NPP) showed up after a massive quake on March 11, 2011. Cesium-137 ((137)Cs) with a half-life of 30.1 y causes the largest concerns because of its deleterious effect on agriculture and stock farming, and, thus, human life for decades. Removal of (137)Cs contaminated soils or land use limitations in areas where removal is not possible is, therefore, an urgent issue. A challenge lies in the fact that estimates of (137)Cs emissions from the Fukushima NPP are extremely uncertain, therefore, the distribution of (137)Cs in the environment is poorly constrained. Here, we estimate total (137)Cs deposition by integrating daily observations of (137)Cs deposition in each prefecture in Japan with relative deposition distribution patterns from a Lagrangian particle dispersion model, FLEXPART. We show that (137)Cs strongly contaminated the soils in large areas of eastern and northeastern Japan, whereas western Japan was sheltered by mountain ranges. The soils around Fukushima NPP and neighboring prefectures have been extensively contaminated with depositions of more than 100,000 and 10,000 MBq km(-2), respectively. Total (137)Cs depositions over two domains: (i) the Japan Islands and the surrounding ocean (130-150 °E and 30-46 °N) and, (ii) the Japan Islands, were estimated to be approximately 6.7 and 1.3 PBq, [corrected] respectively.We hope our (137)Cs deposition maps will help to coordinate decontamination efforts and plan regulatory measures in Japan.

Comprehensive whole-body counter surveys of Miharu-town school children for three consecutive years after the Fukushima NPP accident.

Comprehensive whole-body counter surveys covering over 93% of the school children between the ages of 6 and 15 in Miharu town, Fukushima Prefecture, have been conducted for three consecutive years, in 2011, 2012 and 2013. Although the results of a questionnaire indicate that approximately 60% of the children have been regularly eating local or home-grown rice, in 2012 and 2013 no child was found to exceed the (137)Cs detection limit of 300 Bq/body.

BABYSCAN: a whole body counter for small children in Fukushima.

BABYSCAN, a whole body counter for small children with a detection limit for (137)Cs of better than 50 Bq/body, was developed, and the first unit has been installed at a hospital in Fukushima, to help families with small children who are very much concerned about internal exposures. The design principles, implementation details and the initial operating experience are described.

Whole-body counter survey results 4 months after the Fukushima Dai-ichi NPP accident in Minamisoma City, Fukushima.

Using the first WBC unit installed in Fukushima Prefecture after the accident, the radiocesium body burdens of 566 high-risk residents of Minamisoma city were measured in July 2011 at the Minamisoma Municipal General Hospital. The analysis of the data was challenging because this chair-type, WBC unit, did not have sufficient shielding against background gamma rays and methods had to be developed to reliably compensate for the body-attenuated background radiation. Fortunately, data for repeated tests of hospital staff members using both the chair-type and well-shielded FASTSCAN WBC units, installed in September 2011, were available and could be used to check the validity of the analysis. The CEDs of all subjects, estimated under the assumption of acute inhalation in March 2011, were found to be less than 1 mSv.

Estimation of the total population moving into and out of the 20 km evacuation zone during the Fukushima NPP accident as calculated using "Auto-GPS" mobile phone data.

The first objective data showing the geographical locations of people in Fukushima after the Fukushima Dai-ichi nuclear power plant accident, obtained by an analysis of GPS (Global Positioning System)-enabled mobile phone logs, are presented. The method of estimation is explained, and the flow of people into and out of the 20 km evacuation zone during the accident is visualized.

Internal radiocesium contamination of adults and children in Fukushima 7 to 20 months after the Fukushima NPP accident as measured by extensive whole-body-counter surveys.

The Fukushima Dai-ichi NPP accident contaminated the soil of densely-populated regions in Fukushima Prefecture with radioactive cesium, which poses significant risks of internal and external exposure to the residents. If we apply the knowledge of post-Chernobyl accident studies, internal exposures in excess of a few mSv/y would be expected to be frequent in Fukushima.Extensive whole-body-counter surveys (n = 32,811) carried out at the Hirata Central Hospital between October, 2011 and November, 2012, however show that the internal exposure levels of residents are much lower than estimated. In particular, the first sampling-bias-free assessment of the internal exposure of children in the town of Miharu, Fukushima, shows that the (137)Cs body burdens of all children (n = 1,383, ages 6-15, covering 95% of children enrolled in town-operated schools) were below the detection limit of 300 Bq/body in the fall of 2012. These results are not conclusive for the prefecture as a whole, but are consistent with results obtained from other municipalities in the prefecture, and with prefectural data.

Spectroscopy of antiprotonic helium atoms and its contribution to the fundamental physical constants.

Antiprotonic helium atom, a metastable neutral system consisting of an antiproton, an electron and a helium nucleus, was serendipitously discovered, and has been studied at CERN's antiproton decelerator facility. Its transition frequencies have recently been measured to nine digits of precision by laser spectroscopy. By comparing these experimental results with three-body QED calculations, the antiproton-to-electron massratio was determined as 1836.152674(5). This result contributed to the CODATA recommended values of the fundamental physical constants

Dependence of radiation dose on the behavioral patterns among school children: a retrospective analysis 18 to 20 months following the 2011 Fukushima nuclear incident in Japan.

After radioactive incidents, the exposure risk in daily activities among children is a major public concern. However, there are limited methods available for evaluation of this risk, which is essential to future health risk management. To this end, this study assessed the relationship between behavioral patterns of school children and radiation exposure for a period of 18-20 months following the 2011 Fukushima nuclear incident. The assessed population comprised 520 school children from Minamisoma city, located 20 km north of the nuclear plant. Data for the doses were obtained using individual dosimeters and from results of a behavior survey administered by the City Office. The mean value of the doses in the study period was 0.34 mSv, with a standard deviation of 0.14 mSv, indicating an annual dose of ∼1.36 mSv, which includes doses from natural sources. Our results showed that behavior with respect to outdoor activities had no statistically significant relationship to the dose. A 0.1 µSv/h increase in the air dose rate at home was associated with a 10% increase in the dose; however, a 0.01 µSv/h increase in the air dose rate on the school grounds was associated with a 2% increase in the dose. This study indicates that the air contamination levels at the places where children spend most of their day are the significant predictors of the dose, as opposed to the levels at those outdoor locations in which short periods of time spent.

An evaluation of early countermeasures to reduce the risk of internal radiation exposure after the Fukushima nuclear incident in Japan.

After a radiation-release incident, intake of radionuclides in the initial stage immediately following the incident may be the major contributor to total internal radiation exposure for individuals in affected areas. However, evaluation of early internal contamination risk is greatly lacking. This study assessed the relationship between initial stage evacuation/indoor sheltering and internal radiation contamination levels 4 months after the 2011 Fukushima nuclear incident in Japan and estimated potential pathways of the contamination. The study population comprised 525 participants in the internal radiation screening program at Minamisoma Municipal General Hospital, 23 km north of the Fukushima nuclear plant. The analysed dataset included the results of a screening performed in July 2011, 4 months after the incident, and of a questionnaire on early-incident response behaviours, such as sheltering indoors and evacuations, completed by participants. Association between such early countermeasures and internal contamination levels of cesium-134 were assessed using Tobit multiple regression analyses. Our study shows that individuals who evacuated to areas outside Fukushima Prefecture had similar contamination levels of cesium-134 to individuals who stayed in Fukushima (relative risk: 0.86; 95% confidence interval: 0.74-0.99). Time spent outdoors had no significant relationship with contamination levels. The effects of inhalation from radiological plumes released from the nuclear plant on total internal radiation contamination might be so low as to be undetectable by the whole-body counting unit used to examine participants. Given the apparent limited effectiveness of evacuation and indoor sheltering on internal contamination, the decision to implement such early responses to a radiation-release incident should be made by carefully balancing their potential benefits and health risks.

Buffer-gas cooling of antiprotonic helium to 1.5 to 1.7 K, and antiproton-to-electron mass ratio.

Charge, parity, and time reversal (CPT) symmetry implies that a particle and its antiparticle have the same mass. The antiproton-to-electron mass ratio [Formula: see text] can be precisely determined from the single-photon transition frequencies of antiprotonic helium. We measured 13 such frequencies with laser spectroscopy to a fractional precision of 2.5 × 10-9 to 16 × 10-9 About 2 × 109 antiprotonic helium atoms were cooled to temperatures between 1.5 and 1.7 kelvin by using buffer-gas cooling in cryogenic low-pressure helium gas; the narrow thermal distribution led to the observation of sharp spectral lines of small thermal Doppler width. The deviation between the experimental frequencies and the results of three-body quantum electrodynamics calculations was reduced by a factor of 1.4 to 10 compared with previous single-photon experiments. From this, [Formula: see text] was determined as 1836.1526734(15), which agrees with a recent proton-to-electron experimental value within 8 × 10-10.