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In this study, we assessed the factor structure and construct validity of the parent-reported Inventory of Callous-Unemotional Traits (ICU) among school-aged children and adolescents, aged 6 to 15 years, in a community setting in Japan (n = 10,936). We investigated 15 models that have been reported in previous studies and used confirmatory factor analyses to determine a model that might actually be the best-fit among these. We then examined the correlations between the score of ICU and the Strengths and Difficulties Questionnaire (SDQ) in the best fit model and the three-factor bifactor (3FBF) model with the original ICU through cross-sectional and longitudinal analysis to determine the concurrent and predictive validity of the ICU. The results showed that the best-fit model was the two-factor bifactor (2FBF) model with a revised version of the ICU with 12 items, excluding all but one item of unemotional factors. The cross-sectional and longitudinal analysis showed that higher general callous-unemotional factor scores, callousness and uncaring specific factor scores were significantly associated with a higher level of conduct problems and a lower level of prosocial behaviors in the SDQ. These tendencies were shown both in the 2FBF model with the revised version of the ICU and the 3FBF model with the original ICU. We conclude that the 2FBF model was useful for school-aged community samples, as it predicts increases in conduct problems and decreases in prosocial behavior with fewer items than the 3FBF model. [ABSTRACT FROM AUTHOR]

Objective: To investigate the cost differences between magnetic resonance-guided focussed ultrasound (MRgFUS) and unilateral deep brain stimulation (DBS) for the treatment of medication-refractory essential tremor (ET) in Japan using a cost-minimisation model. Methods: A cost-minimisation model estimated total costs for MRgFUS and unilateral DBS by summing the pre-procedure, procedure, and post-procedure costs over a 12-month time horizon, using data from published sources and expert clinical opinion. The model base case considered medical costs from fee-for-service tariffs. Scenario analyses investigated the use of Diagnosis Procedure Combination tariffs, a diagnosis-related group-based fixed-payment system, and the addition of healthcare professional labour costs healthcare professionals using tariffs from the Japanese Health Insurance Federation for Surgery. One-way sensitivity analyses altered costs associated with tremor recurrence after MRgFUS, the extraction rate following unilateral DBS, the length of hospitalisation for unilateral DBS and the procedure duration for MRgFUS. The impact of uncertainty in model parameters on the model results was further explored using probabilistic sensitivity analysis. Results: Compared to unilateral DBS, MRgFUS was cost saving in the base case and Diagnosis Procedure Combination cost scenario, with total savings of JPY400,380 and JPY414,691, respectively. The majority of savings were accrued at the procedural stage. Including labour costs further increased the cost differences between MRgFUS and unilateral DBS. Cost savings were maintained in each sensitivity analysis and the probabilistic sensitivity analysis, demonstrating that the model results are highly robust. Conclusions: In the Japanese healthcare setting, MRgFUS could be a cost saving option versus unilateral DBS for treating medication-refractory ET. The model results may even be conservative, as the cost of multiple follow-ups for unilateral DBS and treatment costs for adverse events associated with each procedure were not included. This model is also consistent with the results of other economic analyses of MRgFUS versus DBS in various settings worldwide. [ABSTRACT FROM AUTHOR]

Background: The clinical component of medical education for students and resident doctors in Japan occurs almost entirely in the hospital setting. Because of this inpatient focus, graduate medical education clinical training often fails to expose physicians-in-training to the challenges that patients may face in the outpatient or home setting. This is a descriptive study in which we explore what participating students and resident doctors learned through our brief home-based teaching experience. Methods: From June 2016 to December 2017, attending physicians on the internal medicine service had medical students and resident doctors accompany them on home care visits. Participants were selected by convenience sampling based on their rotation availability. After the home visit and the interactive discussion, the participants were expected to prepare a reflective journal on their experience and learning. Thematic analysis was applied, and key themes were developed based on Kolb’s ELT (Experiential learning theory). Three months after completion of the experience, semi-structured interviews were individually conducted assessing participants’ self-perceived changes. Results: Thirty-two medical students(10) or residents(22)participated in a home visit. Thirty of these learners were able to complete a reflective journal. Using thematic analysis, we identified 2 domains and 6 key themes from the participants’ perceptions. Participants recognized the importance of patient-centered care, inter-professional collaboration of the home care team, and reconceptualized the meaning of medical practice and their professional identity as a doctor. Three month post-experience interviews were completed on 12 of the original 30 participants who completed the reflective journal. 2 domains and 6 key themes from the residents’ experiences and perceptions were generated. The participants reported an increased attention to the daily lives and social situations of their hospitalized patients, and an extension of their focus beyond the clinical medical treatment of the patient. Conclusion: The experience of a brief visit to a patient’s home is a novel educational approach that may potentially provide medical students and resident doctors with opportunities to learn about out-of-hospital, patient-centered, home-based medical care. [ABSTRACT FROM AUTHOR]

The Bitcoin market becomes the focus of the economic market since its birth, and it has attracted wide attention from both academia and industry. Due to the absence of regulations in the Bitcoin market, it may be easier to bring some kinds of illegal behaviors. Thus, it raises an interesting question: Is there abnormity or illegal behavior in Bitcoin platforms? To answer this question, we investigate the abnormity in five leading Bitcoin platforms. By analyzing the financial index, i.e. the normalized logarithmic price return, we find that the properties of price return in bitFlyer are completely different from others. To find the possible reasons, we find that the abnormal ask price and bid price appear simultaneously in bitFlyer, which may be potentially linked to either price manipulation or money laundering. It verifies our conjecture that there may be abnormity or price manipulation in Bitcoin platforms. Furthermore, our findings in price return could also provide an innovative and effective method to detect the abnormity in Bitcoin platforms. [ABSTRACT FROM AUTHOR]

Introduction: Only a few, large population-based studies, have reported on whiplash-associated disorder (WAD). However, none of them have investigated the influence of crash severity on WAD outcome. In the present study, we aimed to determine whether crash severity predicts outcomes among patients with no-fault government insurance for acute WAD. Methods: We utilized data from a compulsory, no-fault government automobile liability insurance agency in Japan. Individuals involved in a car accident between April 2001 and June 2015 with residual disabilities reported at the end of the treatment between October 2014 and September 2015 were included. Crash severity was assessed based on property damage costs, size of the other vehicle (large car, medium car, small car, or two-wheeled vehicles), and collision types (rear-end collision, contact with vehicle moving in the same direction, or in the opposite direction). Outcomes included the time to claim closure and the number of treatment visits. Results: We analyzed data for a total of 52,251 individuals (28,571 male and 23,680 female) with a median age of 44 years (range: 2–95 years). The median time to claim closure was 220 days (range: 1–4,938 days), and the median number of treatment visits was 102 (range: 1–2,492). There was no significant association between outcomes and property damage costs or size of the other vehicle. Collision types exhibited no consistent association with outcomes. However, older age and affected body parts, in addition to the neck, were independent risk factors for delayed claim closure and a large number of visits, although, all odds ratios were low (often less than 2.0). Conclusions: There was no obvious association of outcomes with property damage costs, size of the other vehicle, or collision types in acute WAD patients. Further studies should investigate the influence of psychological factors, compensation systems, and cultural conditions. [ABSTRACT FROM AUTHOR]

Purpose: To examine the foveal structure and vasculature in eyes with an idiopathic epiretinal membrane (ERM). Methods: Forty-nine eyes of 48 patients with an idiopathic ERM were studied. The superficial foveal avascular zone (FAZ) was measured by optical coherence tomography angiography (OCTA; RTVue XR Avanti, Optovue Inc., Fremont, CA), and the central foveal thickness (CFT) was measured by swept source OCT (DRI-OCT, Topcon, Japan). Twenty eyes underwent vitrectomy with internal limiting membrane (ILM) peeling, and the FAZ and CFT were evaluated pre- and postoperatively. Forty-nine eyes of 49 age-matched healthy subjects were also examined as control. Results: The FAZ in eyes with an ERM was significantly smaller than that of the control eyes (0.188±0.16 mm2 vs 0.328±0.14 mm2, P<0.01). The CFT in eyes with an ERM was significantly thicker than that of control eyes (315±0.14 μm vs 193±0.14 μm, P<0.01). The size of the FAZ was strongly correlated with the CFT (ERM, R = -0.753; control, R = -0.61, both P<0.01). The postoperative size of the FAZ was not significantly different from the preoperative size (0.115 mm2 vs 0.128 mm2, P = 0.17) but the CFT was significantly thinner (370 μm vs 288 μm, P<0.01) after the vitrectomy with ILM peeling in 20 eyes. Conclusions: The results indicate that an ERM might affect the morphology and vasculature of not only the inner but also the outer retina before and after vitrectomy with ILM peeling. The FAZ area might have been affected by the ILM peeling. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the running pace and step characteristics among various competitive-level 400-m hurdlers through inter-group and intra-athlete comparisons. We analysed spatiotemporal data involving the split time, mean step length (SL) and mean step frequency (SF) for 13 male world-class and 14 male national-level 400-m hurdlers. We analysed 16.5 ± 3.9 races for each world-class hurdler and 19.8 ± 6.0 races for each national-level hurdler (the total number of analysed runs was 491) using publicly available television and internet broadcasts. Inter-group comparisons showed that both first- and latter-halves split times of the world-class hurdlers were significantly shorter than those of the national-level hurdlers. In the latter-half phase, no significant differences of SL and SF were observed between the world-class and national level hurdlers. Intra-athlete comparisons showed that no athletes favoured only first-half phase in terms of running speed in short finish times. In contrast, finish times of all hurdlers were sensitive to running speed in the latter-half phase. In the latter half of the race, 18 of the 27 hurdlers were identified as being SF reliant during speed enhancements; running speed of the other 9 hurdlers were also sensitive to high SF. In conclusions, important findings regarding high performance in inter-group comparisons do not always corresponded with those in intra-athlete comparisons. All athletes and coaches should first prioritize maintaining high running speeds in the latter half of 400-m hurdles rather than in the first half of the race. [ABSTRACT FROM AUTHOR]

The complex nature of mental well-being is reflected in the great diversity of variables thought to represent aspects of mental flourishing. Discovering the underlying structure of mental well-being is important for a full understanding of this complex construct. Using data from 3 countries (the United States, Japan, and Iran), we performed multi-dimensional scaling to analyze the representation of 9 hedonic and eudaimonic well-being variables in a 2-dimensional psychological space. The analyses revealed 2 interpretable underlying dimensions across cultures and gender groups. The first dimension—eudaimonic well-being versus hedonic well-being—is well-known to well-being researchers. The second dimension—existential relatedness versus Epicurean independence—has not been recognized before. Existential relatedness is the characteristic of being meaningfully interconnected with things other than oneself, and is mainly based on the variables positive relations with others, personal growth, purpose in life, and life satisfaction. Epicurean independence is the characteristic of being relatively free of painful experiences and not feeling the need to have ones’ views accepted by anyone but oneself. Epicurean independence is mainly based on the variables autonomy and absence of negative affect. We explain these dimensions in detail and discuss the implications for well-being research and policy. [ABSTRACT FROM AUTHOR]

This study examines how negative shocks due to, for example, natural disasters propagate through supply chains. We apply a simulation technique to actual supply chain data covering most Japanese firms. To investigate the property of the propagation in the network, we test different types of artificial negative shocks. We find that, first, network structures severely affect the speed of propagation in the short run, and the total loss in the long run. The scale-free nature of the actual supply-chain network—that is, the power-law degree distribution—leads to faster propagation. Second, more intensive damages—that is, more damages suffered by fewer firms—result in faster propagation than extensive damages of the same total size. Third, the actual supply-chain network has innate robustness that comes from substitutability of supplies. If the supply-chain network has severe substitutability, the propagation of negative shocks becomes substantially large. Fourth, direct damages in urban regions promote faster propagation than those in rural regions. Fifth, different sectoral damages show significant differences in the speed of propagation. Finally, we check the indirect damage triggered by a single firm’s loss: 9.7% of all firms contribute to significant loss, and this loss accounts for more than 10% of the damage to the entire production. The simulations conspicuously show that different direct damages, even if they have the same total magnitude of damages, can generate considerably different damages because of the structure of the supply-chain network. [ABSTRACT FROM AUTHOR]

Purpose: Abnormal fundus autofluorescence (FAF) potentially precedes onset of late age-related macular degeneration (AMD) in Caucasian patients. Many differences exist between Asian and Caucasian patients regarding AMD types and severity, gender, and genetic backgrounds. We investigated the characteristics of abnormal FAF and retinal sensitivity in the fellow eyes of Japanese patients with unilateral neovascular AMD. Methods: Sixty-six patients with unilateral neovascular AMD and abnormal FAF in the fellow eye were enrolled in this multicenter, prospective, observational study. The best-corrected visual acuity, fundus photographs, FAF images, and retinal sensitivity on microperimetry were measured periodically for 12 months. The FAF images were classified into eight patterns based on the International Fundus Autofluorescence Classification Group. The points measured by microperimetry were superimposed onto the FAF images and fundus photographs and classified as “within,” “close,” and “distant,” based on the distance from the abnormal FAF and other findings. The relationship between the location of the baseline abnormal FAF and retinal sensitivity was investigated. Results: In Japanese patients, patchy (33.3%) and focally increased (30.3%) patterns predominated in the abnormal FAF. Intermediate-to-large drusen was associated predominantly with hyperfluorescence and hypofluorescence. Neovascular AMD developed within 1 year in six (9.1%) eyes, the mean baseline retinal sensitivity of which was 12.8 ± 4.7 dB, significantly (p<0.002) lower than the other eyes. In 44 of the other 60 eyes, microperimetry was measurable at baseline and month 12 and the mean retinal sensitivity improved significantly from 13.5 ± 4.4 to 13.9 ± 4.8 dB (p<0.001), possibly associated with lifestyle changes (e.g., smoking cessation, antioxidant and zinc supplementation). The mean retinal sensitivities of points within and close to the abnormal FAF were 9.9 and 11.7 dB, respectively, which were significantly lower than the 14.0 dB of the points distant from the abnormal FAF. Conclusion: In Japanese patients, patchy and focally increased patterns predominated in the abnormal FAF. The retinal sensitivity was lower close to/within the abnormal FAF. FAF and microperimetry are useful to assess macular function before development of neovascular AMD or geographic atrophy. [ABSTRACT FROM AUTHOR]

Adolescent depression is a significant public health concern. Although skipping breakfast is associated with depressive symptoms in adolescents, the effects of dietary patterns on their depressive symptoms remain unknown. Therefore, this study aims to determine whether dietary patterns are associated with depressive symptoms among junior and senior high school students in Japan. A total of 441 junior high school students and 417 senior high school students participated in this study. The Center for Epidemiologic Studies Depression scale (CES-D) was used to measure the participants’ depressive symptoms. We surveyed the participants’ breakfast consumption pattern, as well as their general dietary patterns (meat, fish, green and yellow vegetables, milk and dairy products, and fruits), using a self-report questionnaire. The results indicated that the senior high school students had a significantly higher CES-D score than the junior high school students. We found negative and significant partial correlations between regular consumption of breakfast and depressive symptoms, and between regular consumption of green and yellow vegetables and depressive symptoms in both junior and senior high school students, after controlling for age, sex, and sleep duration. Furthermore, a one-way analysis of covariance (ANCOVA) revealed that adolescents who consumed green and yellow vegetables every day (one or more times per day) had significantly lower depressive symptoms than those from the “Never/1–2 times a week” group. The findings of this study reveal that the regular consumption of green and yellow vegetables is associated with lower depressive symptoms in adolescents, that is, the consumption of green and yellow vegetables may be vital in the context of adolescents’ mental health. [ABSTRACT FROM AUTHOR]

Concern about mental health issues and the treatment of mentally disordered offenders attracts considerable public attention. This study aimed to gather the experiences and opinions of people who have experienced admission to a psychiatric ward in order to grasp their reaction to, and understanding of, the legislation behind the involuntary admission of psychiatric patients. A web-based questionnaire survey was conducted with a total of 379 participants, using a cross-sectional, exploratory design. The data were analyzed using a chi-squared test, Fisher’s exact test, and a logistic regression analysis. According to the results, many patients were satisfied with their treatment during psychiatric admission; however, only few participants said that they had been given an adequate explanation for their involuntary treatment. Most participants expected qualified assistance after discharge, although the prospect of a regular visit from an official was not entirely supported by the participants. Patient satisfaction was relevant to the discussion of their needs after discharge and in developing a crisis plan during admission. These findings suggest that psychiatric patients accept inpatient treatment as long as they receive an adequate explanation. More qualified care such as relapse prevention would be expected to lead to better satisfaction. For them to welcome regular visits from an official, patients may need more information and discussion. [ABSTRACT FROM AUTHOR]

Various studies have determined that the Great East Japan Earthquake (GEJE) caused mental distress among residents in affected areas. However, previous studies had not considered the prevalence of mental distress before the GEJE, and ignored the impact of an aged society on mental distress. Therefore, we aimed to describe the prevalence of mental distress before the GEJE in Miyagi Prefecture, Japan and elucidate the effect of an aged society on mental distress. We conducted an ecological study, using municipality in Miyagi Prefecture as the study unit. We used the cross-sectional mail survey data conducted in February 2011. We performed a correlation analysis in each of the 39 municipalities in Miyagi Prefecture. The prevalence of serious mental distress was 9.1%. The proportion of the population aged 65 years or older was related to the prevalence of serious mental distress in municipalities with a low proportion of all workers engaged in primary industry and with a high estimated number of inpatients with mental illness. We found that residents in Miyagi Prefecture suffered from poor mental health before the GEJE. Aged society was related to serious mental distress in the areas with advanced industrial structure and more patients with mental illness. We should approach mental health problems in the context of social structure, particularly in an aged society, based on facts about mental distress before the GEJE. [ABSTRACT FROM AUTHOR]

After the severe nuclear disaster in Fukushima, which was triggered by the Great East Japan earthquake in March 2011, nuclear power plants in Japan were temporarily shut down for mandatory inspections. To prevent large-scale blackouts, the Japanese government requested companies and households to reduce electricity consumption in summer and winter. It is reported that the domestic electricity demand had a structural decrease because of the electricity conservation effect (ECE). However, quantitative analysis of the ECE is not sufficient, and especially time variation of the ECE remains unclear. Understanding the ECE is important because Japan’s NDC (nationally determined contribution) assumes the reduction of CO2 emissions through aggressive energy conservation. In this study, we develop a time series model of monthly electricity demand in Japan and estimate time variation of the ECE. Moreover, we evaluate the impact of electricity conservation on CO2 emissions from power plants. The dynamic linear model is used to separate the ECE from the effects of other irrelevant factors (e.g. air temperature, economic production, and electricity price). Our result clearly shows that consumers’ electricity conservation behavior after the earthquake was not temporary but became established as a habit. Between March 2011 and March 2016, the ECE on industrial electricity demand ranged from 3.9% to 5.4%, and the ECE on residential electricity demand ranged from 1.6% to 7.6%. The ECE on the total electricity demand was estimated at 3.2%–6.0%. We found a seasonal pattern that the residential ECE in summer is higher than that in winter. The emissions increase from the shutdown of nuclear power plants was mitigated by electricity conservation. The emissions reduction effect was estimated at 0.82 MtCO2–2.26 MtCO2 (−4.5% on average compared to the zero-ECE case). The time-varying ECE is necessary for predicting Japan’s electricity demand and CO2 emissions after the earthquake. [ABSTRACT FROM AUTHOR]

Background and aim: It is supposed that enhanced oxidative stress and inflammation are involved with the poor clinical outcomes in patients on chronic dialysis treatment. Recent studies have shown that molecular hydrogen (H2) is biologically active as an anti-inflammatory agent. Thus, we developed a novel hemodialysis (E-HD) system which delivers H2 (30 to 80 ppb)-enriched dialysis solution, to conduct a prospective observational study (UMIN000004857) in order to compare the long-term outcomes between E-HD and conventional-HD (C-HD) in Japan. The present interim analysis aimed to look at potential clinical effects of E-HD during the first 12 months observation. Subjects and method: 262 patients (140, E-HD; 122, C-HD) were subjected for analysis for comprehensive clinical profiles. They were all participating in the above mentioned study, and they had been under the respective HD treatment for 12 consecutive months without hospitalization. Collected data, such as, physical and laboratory examinations, medications, and self-assessment questionnaires on subjective symptoms (i.e., fatigue and pruritus) were compared between the two groups. Results: In a 12-month period, no clinical relevant differences were found in dialysis-related parameters between the two groups. However, there were differences in the defined daily dose of anti-hypertensive agents, and subjective symptoms, such as severe fatigue, and pruritus, which were all less in the E-HD group. Multivariate analysis revealed E-HD was an independent significant factor for the reduced use of anti-hypertensive agents as well as the absence of severe fatigue and pruritus at 12 months after adjusting for confounding factors. Conclusion: The data indicates E-HD could have substantial clinical benefits beyond conventional HD therapy, and support the rationale to conduct clinical trials of H2 application to HD treatment. [ABSTRACT FROM AUTHOR]

Objective: The Great East Japan Earthquake occurred on 11 March 2011 near the northeast coast of the main island, ‘Honshu’, of Japan. It wreaked enormous damage in two main ways: a giant tsunami and an accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP). This disaster may have affected the distribution of physicians in the region. Here, we evaluate the effect of the disaster on the distribution of hospital physicians in the three most severely affected prefectures (Iwate, Miyagi, and Fukushima). Methods: We obtained individual information about physicians from the Physician Census in 2010 (pre-disaster) and 2012 (post-disaster). We examined geographical distributions of physicians in two ways: (1) municipality-based analysis for demographic evaluation; and (2) hospital-based analysis for geographic evaluation. In each analysis, we calculated the rate of change in physician distributions between pre- and post-disaster years at various distances from the tsunami-affected coast, and from the restricted area due to the FDNPP accident. Results: The change in all, hospital, and clinic physicians were 0.2%, 0.7%, and −0.7%, respectively. In the municipality-based analysis, after taking account of the decreased population, physician numbers only decreased within the restricted area. In the hospital-based analysis, hospital physician numbers did not decrease at any distance from the tsunami-affected coast. In contrast, there was a 3.3% and 2.3% decrease in hospital physicians 0–25 km and 25–50 km from the restricted area surrounding the FDNPP, respectively. Additionally, decreases were larger and increases were smaller in areas close to the FDNPP than in areas further away. Conclusions: Our results suggest that the tsunami did not affect the distribution of physicians in the affected regions. However, the FDNPP accident changed physician distribution in areas close to the power plant. [ABSTRACT FROM AUTHOR]

Riding a bicycle under the influence of alcohol is illegal in Japan. Nevertheless, intoxicated bicyclists are frequently treated at hospital emergency departments for bicycle-related injuries. This patient population usually requires more hospital resources, even for relatively minor injuries. Therefore, we hypothesized that bicycle-related crashes involving bicyclists under the influence of alcohol cost more to treat than those that do not involve alcohol intoxication. The aim of the present study was to examine the costs associated with bicycle-related minor injuries and alcohol intoxication of the bicyclist. The study was conducted at the Tokyo Bay Urayasu Ichikawa Medical Center Emergency Department, Japan. All minor bicycle crashes involving 217 individuals aged ≥20 years treated from September 1, 2012 to August 31, 2013 were included in the analysis of data obtained from medical records. Variables included alcohol intoxication, sex, age, collision with a motor vehicle, Glasgow Coma Scale, injury severity score (ISS), laboratory tests, treatment of wounds, number of X-ray images, number of computed tomography scans, and medical costs. Multiple linear regression analysis was performed to evaluate the association between alcohol intoxication and medical costs. Seventy (32%) patients consumed alcohol, and the median medical cost was 253 USD (interquartile range [IQR], 164–330). Multivariable analysis showed that alcohol intoxication was independently associated with higher medical costs (p = 0.030, adjusted R-square value = 0.55). These findings support our hypothesis and should encourage authorities to implement comprehensive measures to prohibit bicycling under the influence of alcohol to prevent injuries and to reduce medical costs. [ABSTRACT FROM AUTHOR]

Objective: The shortage of physicians after a major disaster is a crucial issue. We aimed to evaluate the characteristics of physicians who left affected areas following the accident at Fukushima Daiichi Nuclear Power Plant caused by the Great East Japan Earthquake on March 11, 2011. Methods: Using data from a physician census conducted in 2010 (pre-disaster) and 2012 (post-disaster), we evaluated changes in the number of physicians in affected areas. We then calculated the odds ratios and 95% confidence intervals using a logistic regression model to evaluate the association between physician characteristics and outflow. We also conducted stratified analyses based on physician characteristics. Results: The number of physicians decreased in Fukushima Prefecture (–5.3%) and increased in Miyagi Prefecture (2.8%). The decrease in Fukushima and increase in Miyagi were evident even after taking the prefecture’s population change into account (change in physician to population ratios: –1.9% and 3.2%, respectively). Compared with physicians who lived in areas >100 km from the nuclear power plant, physicians living 20–50 km and 50–100 km were, respectively, 3.9 times (95% confidence interval, 2.6–5.7) and 2.6 times (95% confidence interval, 1.7–3.8) more likely to migrate to distant areas. In the stratified analysis, younger physicians and those earlier in their careers had higher odds ratios for outflow than other physicians (P for interaction = 0.02 and <0.01, respectively). Conclusions: The risk of outflow was greater among younger and early-career physicians in areas around the power plant. Political support may be necessary to recruit and retain such physicians, who will be responsible for future community health in the disaster area. [ABSTRACT FROM AUTHOR]

Introduction: In 2011, Fukushima was struck by a triple disaster: an earthquake, tsunamis, and a nuclear accident. In the aftermath, there was much fear among hospital staff members about radiation exposure and many staff members failed to report to work. Objectives: One objective is to measure this shortage in hospital staff and another is to compare the difference in recovery by hospital types and by categories of hospital staff. Design: The monthly records of the number of staff members from May 2011 to September 2012 were extracted anonymously from the records of 7 local hospitals in the Soso district in Fukushima. Change in the number of staff was analyzed. Results: Staff shortages at hospitals reached a maximum within one month after the disaster (47% reported to work). The shortage of clerks was the most severe (38% reported to work), followed by nurses (48% reported to work). The shortages remained even 18 months after the disaster. Conclusion: After a disaster in which the damage to hospital functions surpasses the structural damage, massive support of human resources in the acute phase and a smaller volume of support in the mid-term phase appear to be required, particularly for non-medical staff. [ABSTRACT FROM AUTHOR]

Background: We sought to examine social network diversity as a potential determinant of oral health, considering size and contact frequency of the social network and oral health behaviors. Methods: Our cross-sectional study was based on data from the 2010 Japan Gerontological Evaluation Study. Data from 19,756 community-dwelling individuals aged 65 years or older were analyzed. We inquired about diversity of friendships based on seven types of friends. Ordered logistic regression models were developed to determine the association between the diversity of social networks and number of teeth (categorized as ≥20, 10–19, 1–9, and 0). Results: Of the participants, 54.1% were women (mean age, 73.9 years; standard deviation, 6.2). The proportion of respondents with ≥20 teeth was 34.1%. After adjusting for age, sex, socioeconomic status (income, education, and occupation), marital status, health status (diabetes and mental health), and size and contact frequency of the social network, an increase in the diversity of social networks was significantly associated with having more teeth (odds ratio = 1.08; 95% confidence interval, 1.04–1.11). Even adjusted for oral health behaviors (smoking, curative/preventive dental care access, use of dental floss/fluoride toothpaste), significant association was still observed (odds ratio = 1.05 (95% confidence interval, 1.02–1.08)). Conclusion: Social connectedness among people from diverse backgrounds may increase information channels and promote the diffusion of oral health behaviors and prevent tooth loss. [ABSTRACT FROM AUTHOR]

The ability to ascertain the extent of product sale fluctuations for each store and locality is indispensable to inventory management. This study analyzed POS data from 158 convenience stores in Kawasaki City, Kanagawa Prefecture, Japan and found a power scaling law between the mean and standard deviation of product sales quantities for several product categories. For the statistical domains of low sales quantities, the power index was 1/2; for large sales quantities, the power index was 1, so called Taylor’s law holds. The value of sales quantities with changing power indixes differed according to product category. We derived a Poissonian compound distribution model taking into account fluctuations in customer numbers to show that the scaling law could be explained theoretically for most of items. We also examined why the scaling law did not hold in some exceptional cases. [ABSTRACT FROM AUTHOR]

Recent advances in the use of summed probability distribution (SPD) of calibrated 14C dates have opened new possibilities for studying prehistoric demography. The degree of correlation between climate change and population dynamics can now be accurately quantified, and divergences in the demographic history of distinct geographic areas can be statistically assessed. Here we contribute to this research agenda by reconstructing the prehistoric population change of Jomon hunter-gatherers between 7,000 and 3,000 cal BP. We collected 1,433 14C dates from three different regions in Eastern Japan (Kanto, Aomori and Hokkaido) and established that the observed fluctuations in the SPDs were statistically significant. We also introduced a new non-parametric permutation test for comparing multiple sets of SPDs that highlights point of divergences in the population history of different geographic regions. Our analyses indicate a general rise-and-fall pattern shared by the three regions but also some key regional differences during the 6th millennium cal BP. The results confirm some of the patterns suggested by previous archaeological studies based on house and site counts but offer statistical significance and an absolute chronological framework that will enable future studies aiming to establish potential correlation with climatic changes. [ABSTRACT FROM AUTHOR]