Strength dependency of frequency-magnitude distribution in earthquakes and implications for stress state criticality.

Earthquake size distribution is characterized by the "b-value" of the power law decay, which exhibits spatiotemporal variations. These variations are sometimes evident before a large earthquake. Understanding spatiotemporal variations is key to developing a model for large-earthquake generation. Previous studies have shown that changes in the b-value are caused by the tectonic stress regime. Furthermore, lab experiments have demonstrated the b-value dependency of acoustic emissions on the criticality of the failure condition. However, the factors controlling the b-values during natural seismic activity are unclear. In this study, changes in the b-value in small earthquake sequences are investigated, focusing on failure criticality. Based on our high-precision focal mechanism dataset, we conclude that the b-value decreases as it nears a critical failure condition, providing a physical explanation for the reduction in b-value before a major earthquake. Our findings elucidate fault failure models, facilitating improvement in earthquake alerts and disaster mitigation.

A review on management practices, environmental impacts, and human exposure risks related to electrical and electronic waste in Vietnam: findings from case studies in informal e-waste recycling areas.

Electrical and electronic waste (e-waste) has become a global concern, especially in developing countries. In this review, we conducted a literature survey of e-waste management practices, processing activities, and adverse effects in Vietnam, an emerging country in Southeast Asia, by gathering data from peer-reviewed articles published between 2009 and 2021. This is the first review paper to comprehensively discuss management and research aspects regarding e-waste in an Asian developing country. Due to the lack of an effective management and recycling system, a certain portion of Vietnamese e-waste has been processed by informal sectors without appropriate recycling and pollution control technology, resulting in localized contamination and human exposure to toxic chemicals. Primitive processing activities, such as manual dismantling, open burning, and plastic recycling, have been identified as important contributors to the environmental emission and human exposure to toxic elements (notably As, Mn, Ni, Pb, Zn) and organic pollutants like flame retardants, PAHs, PCBs, and dioxin-related compounds. Informal e-waste processing from these small-scale workshops can release pollutants at similar levels compared to large-scale facilities in developed countries. This fact suggests an urgent need to develop management best practices for e-waste in Vietnam as well as other emerging and developing countries, in order to increase recycling efficiency and minimize their adverse impacts on environmental and human health.

Earth-shaking J. LEAGUE supporters.

We conducted temporary seismic observations at the Hitachi-Kashiwa Soccer Stadium on a J. LEAGUE game day to obtain unique seismic records due to the collective action (i.e., jumping) of supporters, which were also recorded in a permanent Metropolitan Seismic Observation network (MeSO-net) station. This study investigated seismic wave excitation as well as seismic wave propagation from the stadium to its surroundings. The rhythms of the jumps of the supporters were characterized by analyzing audio data recorded in the stadium, which were compared with the characteristic frequencies observed in the seismic records. The characteristic frequencies in the seismic records are integer multiples of the jumping rhythms, which is consistent with the loading model of jumping people proposed in earlier studies. This implies that seismometers could be useful for monitoring collective human activity. Travel times were studied using deconvolved waveforms because seismic waves generated by the supporters are sinusoidal with vague onset. Polarization analysis was performed to measure the amplitude and polarization azimuths. The observed seismic wave propagation was compared with synthetic waveforms calculated using one-dimensional physical properties based on the Japan Seismic Hazard Information Station (J-SHIS). The synthetic waveforms calculated with the shallow and deep layer combined model are more consistent with observations of travel times and amplitude decay than those calculated with the only deep layer model, although a part of the observations cannot be explained by both models. This result suggests that the subsurface structure of J-SHIS is good in this region, although a more detailed three-dimensional structure and topography must be considered to fully explain the observations. As human-induced seismic signals are expected to be generated in various situations, this study shows that such unique seismic waves can be used as an artificial seismic source for validating and improving local shallow subsurface structural models in urban environments.

Factors affecting multiple persistent organic pollutant concentrations in the air above Japan: A panel data analysis.

Numerous reports have elucidated different statistical approaches to identify temporal trends in atmospheric persistent organic pollutant (POP) time series. However, the correlation of industrial activity with concentrations of atmospheric POPs in Japan has not yet been determined. Herein, a panel data analysis of a 16-year monitoring program (2003-2018) conducted by the Japanese Ministry of Environment was used to investigate a range of POPs in the atmosphere above Japan. This work focuses on polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB), and pentachlorobenzene (PeCBz) collected each year at 53 sites across Japan. The panel analysis revealed that PCB, PCN, and PBDE concentrations were influenced by a combination of factors including year, industrial activity (municipal and industrial waste incinerators, cement kilns, steel industry, and secondary zinc production), population, temperature, and atmospheric boundary layer. However, HCB and PeCBz were not significantly affected by these factors. Industrial activity showed stronger positive correlations with all homologues of PCBs, PCNs, and PBDEs as compared to those demonstrated by population. Significant decreasing trends were identified for the atmospheric ∑PBDEs (half-life t1/2 = 9.4 years), ∑PCNs (t1/2 = 8.9 years), and ∑PCBs (t1/2 = 13.5 years) concentrations, while HCB and PeCBz showed slightly increasing or steady levels. As a statistical tool, panel data analysis can contribute to the assessment of spatial and temporal trends of POPs at a national scale, while elucidating different behavioral responses to numerous environmental variables.

Emission of Dioxin-like Compounds and Flame Retardants from Commercial Facilities Handling Deca-BDE and Their Downstream Sewage Treatment Plants.

Commercial mixtures of decabromodiphenyl ether (deca-BDE), a brominated flame retardant, contain not only polybrominated diphenyl ethers (PBDEs, mainly BDE-209) as the main component but also dioxin-like compounds (DLCs) such as polybrominated dibenzofurans (PBDFs). Deca-BDE handling facilities (DHFs) and sewage treatment plants receiving effluent from DHFs are point sources of DLC and flame retardant (FR) pollution. Here, we examined their emission in Japan. For DHF effluents, DLCs detected by the dioxin-responsive chemically activated luciferase expression (DR-CALUX) assay were 1.3-890 pg TCDD-EQ/L (median 46 pg TCDD-EQ/L), while PBDEs and other FRs were <2.0-110,000 ng/L (610 ng/L) and 150-4,800,000 ng/L (41,000 ng/L). Risk quotients based on predicted no-effect concentrations suggested that DLCs, decabromodiphenyl ethane (DBDPE), tris(2,3-dibromopropyl) isocyanurate (TDBP-TAZTO), and bisphenol A bis(diphenyl phosphate) (BPA-BDPP) present significant risks for aquatic organisms. The concentrations of PBDFs, which are impurities in deca-BDE, were expected to decrease with the inclusion of deca-BDE in the Stockholm Convention list of persistent organic pollutants (May 2017). However, DLCs other than PBDFs and alternative FRs such as DBDPE, TDBP-TAZTO, and BPA-BDPP are likely still discharged. Additional findings indicate that strong (e.g., DLCs, DBDPE, and BPA-BDPP), but not weak (e.g., TDBP-TAZTO), hydrophobic compounds are sufficiently removed by current wastewater treatment processes in Japan.

Use of comprehensive target analysis for determination of contaminants of emerging concern in a sediment core collected from Beppu Bay, Japan.

In recent years, concern about the release of anthropogenic organic micropollutants referred to as contaminants of emerging concern (CECs) has been growing. The objective of this study was to find potential CECs by means of an analytical screening method referred to as comprehensive target analysis with an automated identification and quantification system (CTA-AIQS), which uses gas and liquid chromatography combined with mass spectrometry (GC-MS and LC-QTOF-MS). We used CTA-AIQS to analyze samples from a sediment core collected in Beppu Bay, Japan. With this method, we detected 80 compounds in the samples and CTA-AIQA could work to useful tool to find CECs in environmental media. Among the detected chemicals, three PAHs (anthracene, chrysene, and fluoranthene) and tris(isopropylphenyl)phosphate (TIPPP) isomers were found to increase in concentration with decreasing sediment depth. We quantified TIPPP isomers in the samples by means of targeted analysis using LC-MS/MS for confirmation. The concentration profiles, combined with previous reports indicating persistent, bioaccumulative, and toxic properties, suggest that these chemicals can be categorized as potential CECs in marine environments.

Time series of hexabromocyclododecane transfers from flame-retarded curtains to attached dust.

While the production and new use of hexabromocyclododecane (HBCD) mostly ceased after being listed as a persistent organic pollutant under the Stockholm Convention in 2013, its emission from treated products in use to indoor environments still deserves attention. To examine the transfer of HBCD diastereomers to dust on the surface of flame-retarded curtains and to better characterize the potential of treated fabrics to be sources of HBCD in dust, we carried out a series of 196-day experiments using two types of curtains and attached dusts. Concurrently, the physicochemical properties (vapor pressure, water solubility, and octanol-water partition coefficient) of the HBCD diastereomers were measured. HBCD diastereomers migrated from curtains to dust with half-saturation times of about 20-50 days. By day 196, mean HBCD concentrations in dust had reached 13-290 µg/g, depending on the types of curtains and dusts. The composition of HBCD, dominated by γ-HBCD in the curtains, was dominated by α-HBCD in the post-experiment dusts, probably because of the higher vapor pressure of α-HBCD compared to γ-HBCD. The initial HBCD contents of the two curtains were comparable, but the concentrations and profiles of HBCD diastereomers in the post-experiment dusts differed markedly, probably because differences between the texture and/or surface finishing of the treated fabrics affected HBCD transfer to the attached dust.

Analysis of mismanaged plastic waste in Samoa to suggest proper waste management in Pacific island countries.

Pacific island countries are facing critical challenges in managing the growing amount of increasingly diverse wastes because of changing lifestyles and the concentration of populations in urban areas. Although marine plastic waste is an issue in the Pacific region, there have been almost no studies of the estimation and impacts of ocean plastic waste, and measures to control such waste, in these countries. Here, first we conducted a questionnaire survey about consumption and disposal of plastic products at households in Samoa as one of the examples of Pacific island countries to grasp the flow of plastic materials and awareness or behaviour for plastic waste. Then we quantified ocean plastic waste and discussed the effective and needed countermeasures in Pacific island countries. The total amount of mismanaged plastic waste was estimated to be 327,000 or 156,000 t y-1 (depending on the scenario) in Pacific island countries. The regional Pacific island countries contribution to the global total mismanaged plastic waste was estimated to range from 1.3% to 2.7%. The amount of mismanaged plastic waste per capita in some Pacific island countries, such as Solomon Islands and Micronesia, was also ranked highly globally. The main reasons seem to be that waste collection rates are relatively low in rural areas and rates of plastic waste generation are high. To implement solutions, including improving municipal solid waste collection, reducing plastic waste, improving the collection and recycling of plastics, and the integration of a number of policies is essential.

Historical and future polychlorinated biphenyl emission trends in Japan.

Different countries produce varying amounts of polychlorinated biphenyls (PCBs), have distinct patterns of use, and regulations for treatment and disposal. Therefore, long-term countermeasures require an understanding of historical and future emission trends at the national scale. In this study, we estimate historical PCB emissions from products containing PCBs, unintentional production related thermal processes, and disposal processes for products containing PCBs from 1950 to 2030 in Japan. In addition, in order to validate the results, we estimated PCB concentrations in environmental media using an environmental fate model and a sensitivity analysis was conducted. Our results show that total PCB emissions were approximately 2.6 tons in 2017, which was a dramatic decrease from peak emissions of 68.9 tons in 1970. We suggest that PCB emissions may continue to decrease, reaching 0.707 tons in 2030. This trend might be due to a change in the emission source; it was estimated that the main emission source in past and recent years was volatilization from large products containing PCBs. However, it is predicted that the main emission sources in the future will be unintentional PCB production from thermal processes and volatilization from small untreated products containing PCBs, although the estimation of environmental PCB levels suggested that there might be unknown emission sources. Additionally, the sensitivity analysis indicated that some parameters greatly influenced the estimation of recent and future emissions. In particular, there was no detailed information concerning the applications for PCBs, which potentially had a large influence on the estimation of future emissions.

Characteristics of gas from the fluidized bed gasification of refuse paper and plastic fuel (RPF) and wood biomass.

Energy recovery from small and medium scale waste thermal treatment facilities in the municipalities of Japan is challenging, owing to low power generation efficiency and high economic demands. Gas Engine (GE) generation is considered an efficient resource utilization method in these facilities. In this study, new and consistent feedstock, Refuse Paper and Plastic Fuel (RPF), and wood pellets were tested in an air-blown Fluidized Bed Gasifier (FBG) for syngas utilization in a GE. With temperatures ranging from 700 to 940 °C and varying Equivalence Ratios (ER) of 0.3-0.5, some of the most important product gas characteristics were analyzed, including the Lower Heating Value (LHV) and tar concentration levels. Gas composition results revealed that the concentration tendencies varied for the product gases CO, H2, and hydrocarbons, depending on the feedstock type, whereas the same tendencies were observed for CH4 and tar concentrations. Through the ER range, the LHV of product gas for RPF and wood pellets was 3.4-5.9 MJ/Nm3. Tar concentrations decreased to 2.5-14.0 g/Nm3-dry as the ER was raised. The optimal ER for LHV performance in GE generation was approximately 0.4 for RPF and wood pellets, and remaining tar concentrations were about 5.0 g/Nm3-dry at the gasifier exit.

Disaster waste management after the 2016 Kumamoto Earthquake: A mini-review of earthquake waste management and the Kumamoto experience.

Millions of tons of debris can be generated by natural disasters, impacting the surrounding environment and posing health risks to the public. Proper handling and treatment of such waste is essential to overcome potential hazards as well as to reduce the burden on natural resources during the reconstruction phase. Disaster waste management can have social, economic, and environmental benefits if planned effectively. This mini-review focuses on the destruction caused and debris generated by the 2016 Kumamoto Earthquake in Japan. In addition, it elaborates upon the treatment of debris in Kumamoto at temporary and secondary storage sites by segregation and the adoption of a full-scale recycling system. It also shows that cooperative networks involving numerous organizations are important in managing a large amount of disaster waste. Finally, it presents comparative discussions of different aspects of disaster waste management in the Kumamoto Earthquake event and other disasters. The experience gained from the Kumamoto Earthquake is important for future disaster waste management planning.

Recycling Potentials of Precious Metals from End-of-Life Vehicle Parts by Selective Dismantling.

Recycling of some minor but essential scarce metals used in vehicles may serve as an important strategy to strengthen sustainable management of natural resources. Accordingly, this study focused on five precious metals (PMs): Au, Ag, Pt, Pd, and Rh, in both end-of-life conventional and next-generation vehicles. To explore their recycling potentials in Japan, we developed substance flow and scenario analyses based on estimations of PM contents per end-of-life vehicle (ELV) and ELV generations. The study predicts that in Japan, from 2015 to 2040, the content of PMs per ELV will range from 2 to 6 g, and the annual amount of PMs in ELVs will remain largely stable, at 14-15 t, but the proportions of PMs utilized in different vehicles, parts, and components will gradually change; in particular, increased proportions will occur in the printed wiring boards (PWBs) of next-generation vehicles. The results also show that, in Japan, totals of 33-53% of PMs in ELVs were recycled in 2015, and that by selective dismantling of PWBs and heating wires in the rear windows of ELVs, the recycling potentials of PMs could be optimally increased to a maximum of 62-83% by 2040.

Clinical Characteristics of Nonobese Patients with Acute Coronary Syndrome and Increased Epicardial Fat Volume.

AIM: Increased epicardial fat volume (EFV) is an independent risk factor for acute coronary syndrome (ACS). Although EFV increases with body mass index (BMI), some ACS patients have an increased EFV but normal BMI. We here investigated the clinical characteristics of nonobese ACS patients with an increased EFV. METHODS: A total of 197 Japanese patients hospitalized for ACS was evaluated for EFV, abdominal visceral fat area (VFA), and lipid and glucose profiles. Control subjects comprised 141 individuals who were suspected of having ACS but whose coronary computed tomography findings were normal. RESULTS: EFV was increased in ACS patients compared with control subjects (120±47 versus 95±45 mL, P＜0.01). ACS patients were divided into four groups based on average EFV (120 mL) and a BMI obesity cutoff of 25 kg/m2. For the 30 nonobese ACS patients with an above-average EFV, EFV was positively correlated with VFA (r=0.23, P=0.031). These individuals were significantly older (74±10 years) and tended to have a higher homeostasis model assessment-insulin resistance value (5.5±3.8) compared with other ACS patients. Among nonobese study subjects, EFV was independently associated with ACS (odds ratio=2.01, P=0.021) and correlated with abdominal circumference (r=0.26, P=0.017). CONCLUSION: Nonobese ACS patients with an increased EFV were elderly and tended to manifest insulin resistance. Measurement of EFV may prove informative for evaluation of ACS risk among elderly nonobese individuals with an increased abdominal girth.

Thermal destruction of wastes containing polychlorinated naphthalenes in an industrial waste incinerator.

A series of verification tests were carried out in order to confirm that polychlorinated naphthalenes (PCNs) contained in synthetic rubber products (Neoprene FB products) and aerosol adhesives, which were accidentally imported into Japan, could be thermally destroyed using an industrial waste incinerator. In the verification tests, Neoprene FB products containing PCNs at a concentration of 2800 mg/kg were added to industrial wastes at a ratio of 600 mg Neoprene FB product/kg-waste, and then incinerated at an average temperature of 985 °C. Total PCN concentrations were 14 ng/m3N in stack gas, 5.7 ng/g in bottom ash, 0.98 ng/g in boiler dust, and 1.2 ng/g in fly ash. Destruction efficiency (DE) and destruction removal efficiency (DRE) of congener No. 38/40, which is considered an input marker congener, were 99.9974 and 99.9995 %, respectively. The following dioxin concentrations were found: 0.11 ng-TEQ/m3N for the stack gas, 0.096 ng-TEQ/g for the bottom ash, 0.010 ng-TEQ/g for the boiler dust, and 0.072 ng-TEQ/g for the fly ash. Since the PCN levels in the PCN destruction test were even at slightly lower concentrations than in the baseline test without PCN addition, the detected PCNs are to a large degree unintentionally produced PCNs and does not mainly stem from input material. Also, the dioxin levels did not change. From these results, we confirmed that PCNs contained in Neoprene FB products and aerosol adhesives could be destroyed to a high degree by high-temperature incineration. Therefore, all recalled Neoprene FB products and aerosol adhesives containing PCNs were successfully treated under the same conditions as the verification tests.

Monitoring environmental burden reduction from household waste prevention.

In this study, the amount of prevented household waste in Kyoto city was quantified using three methods. Subsequently, the greenhouse gas (GHG) emission reduction by waste prevention was calculated in order to monitor the impact of waste prevention. The methods of quantification were "relative change from baseline year (a)," "absolute change from potential waste generation (b)," and "absolute amount of activities (c)." Method (a) was popular for measuring waste prevention, but method (b) was the original approach to determine the absolute amount of waste prevention by estimating the potential waste generation. Method (c) also provided the absolute value utilizing the information of activities. Methods (b) and (c) enable the evaluation of the waste prevention activities with a similar baseline for recycling. Methods (b) and (c) gave significantly higher GHG reductions than method (a) because of the difference in baseline between them. Therefore, setting a baseline is very important for evaluating waste prevention. In practice, when focusing on the monitoring of a specific policy or campaign, method (a) is an appropriate option. On the other hand, when comparing the total impact of waste prevention to that of recycling, methods (b) and (c) should be applied.

Trends in physiological coagulation factors in Japanese patients receiving novel oral anticoagulants.

BACKGROUND: Little is known about physiological anticoagulation effects via antithrombin III (AT III) and protein C/S (PC/PS) in patients using new oral anticoagulants (NOACs). METHODS: We evaluated 120 consecutive patients with non-valvular atrial fibrillation (AF) receiving NOACs. Patients were randomly divided into three groups: a dabigatran group (DG, N=40), a rivaroxaban group (RG, N=40) or an apixaban group (AG, N=40). A warfarin group (WG, N=40) was matched with NOAC groups for age, sex and type of AF during the same time period. Blood samples were obtained in pretreatment, trough and peak phases to measure the activity of physiological coagulation inhibitors, including AT III and PC/PS or thrombus formation markers such as D-dimer and thrombin-antithrombin complex (TAT). RESULTS: D-dimer, TAT and AT III values for the NOAC groups were equivalent in the peak and trough phases. PC/PS activity in both phases was equally maintained in the pretreatment phase in the NOAC groups, while the activity in the WG was significantly suppressed in steady state. Moreover, no differences in trends for PC/PS activity were observed among NOAC groups. CONCLUSIONS: PC/PS activity was constant in both peak and trough phases in the patients on NOACs compared with activity of those on warfarin. In addition, there was no difference in the findings among NOACs.

Correlation between Atmospheric Boundary Layer Height and Polybrominated Diphenyl Ether Concentrations in Air.

In this study, we aim to determine the correlation between the height of the atmospheric boundary layer (ABL) and the concentrations of polybrominated diphenyl ether (PBDE) congeners, in an effort to improve comprehension of the atmospheric behavior of PBDEs. We used the PBDE data in air (n = 298), which were measured by the Japan Ministry of Environment (JMOE) at 50 sites across Japan during the period 2009-2012. The height of the ABL, which directly affects the PBDE concentrations in the near-surface air, was estimated by employing data retrieved from the Japanese global reanalysis (JRA-55) database, using the parcel and Richardson number method. The ABL has shown a strong inverse relationship with BDE-47 and BDE-99 (p < 0.01). In contrast, there was less correlation between BDE-209 and the ABL (p = 0.258). These differing behaviors could be explained by differences in particle size distribution of PBDEs, where BDE-47 and BDE-99 are associated with gas phases and fine particles and BDE-209 is associated with coarse particles. To our knowledge, this paper represents the first large-scale analysis of correlations between the ABL and the concentrations of PBDEs in the air.

Increased expression of the adipocytokine omentin in the epicardial adipose tissue of coronary artery disease patients.

BACKGROUND AND AIMS: Omentin, an adipocytokine secreted by visceral adipose tissue, protects against obesity-linked cardiovascular complications. However, little is known about its role in epicardial adipose tissue (EAT) and coronary artery disease (CAD). We investigated the expression of omentin in EAT from CAD subjects. METHODS: EAT, subcutaneous adipose tissue (SCAT), and plasma samples were collected from CAD (n = 15; 23.3 ± 3.1 kg/m(2)) and non-CAD patients (n = 10; 20.8 ± 3.9 kg/m(2)). Omentin mRNA expression was measured using real-time PCR, while plasma concentrations were measured using an ELISA. EAT volume was determined with 64-slice computed tomography. RESULTS: Omentin expression in EAT and EAT volume were higher in CAD patients compared with controls (2.49 ± 2.6 vs. 0.85 ± 0.3, p = 0.002 and 113 ± 58 ml vs. 92.4 ± 30 ml, p = 0.045, respectively). Omentin expression in SCAT was similar between CAD and control patients (1.37 ± 0.84 vs. 1.07 ± 0.55, p = 0.267). Plasma omentin levels were lower in CAD patients compared with controls (343 ± 158 ng/ml vs. 751 ± 579 ng/ml, p = 0.025), and were negatively associated with the expression of omentin in EAT, in patients with CAD (ß = -0.78, p = 0.049). On the other hand, there was no association between omentin in EAT and clinical variables in patients with non-CAD. CONCLUSIONS: Omentin expression increases in the EAT of non-obese CAD patients, despite a decrease in plasma levels, suggesting that omentin may play a role in the pathogenesis of CAD.

Relationship between QRS score and microvascular obstruction after acute anterior myocardial infarction.

BACKGROUND: The QRS score on electrocardiogram (ECG) in patients with myocardial infarction (MI) reportedly reflects the severity of myocardial damage. The presence of microvascular obstruction (MO) assessed by cardiac magnetic resonance (CMR) imaging is associated with irreversible myocardial damage. MO assessed by CMR is known to be a predictor for adverse clinical outcome after ST-elevation MI. The aim of the present study was to examine the relationship between QRS score and MO in acute anterior MI patients. METHODS: Sixty-two patients with first acute anterior MI who successfully underwent primary percutaneous coronary intervention (PCI) were enrolled. The QRS score after PCI on admission ECG was calculated by a Selvester-Wagner QRS scoring system. CMR imaging was performed at 11.4±3.9 days after MI. MO was defined as delayed enhancement with contrast-devoid core. Patients were divided into two groups as follows: 37 patients who showed MO (MO group) and 25 patients who did not show it (non-MO group). RESULTS: The QRS score was significantly greater in the MO group than in the non-MO group. The QRS score significantly correlated with MO volume (r=0.418, p=0.010). Multivariate analysis showed that the QRS score (odds ratio 1.362, 95% CI: 1.038-1.951, p=0.024) and the peak creatine kinase levels (odds ratio 1.001, 95% CI: 1.000-1.002, p<0.001) were independent predictors for MO. CONCLUSIONS: Our results indicate that the QRS score derived from simple and widely available ECG may be a useful parameter for assuring the presence of MO.

Factors influencing atmospheric concentrations of polybrominated diphenyl ethers in Japan.

We used polybrominated diphenyl ether (PBDE) data in air at 38 sites across Japan (2009-2012), which were measured by the Japan Ministry of Environment (JMOE), to elucidate the time trend and seasonality of atmospheric PBDEs. In order to address few (7% for BDE-47) to many (63% for BDE-153 and 183) non-detect data, Tobit model, also called a censored regression model was used. The model revealed that the concentrations of PBDE congeners were influenced by a combination of year, temperature, rainfall rate, and population density. Greater declines were observed for BDE-47, -99, -153 and -183 (-21, -25, -17, -23%/year, p < 0.05) than for BDE-209 (-6%/year, p = 0.065). These trends were consistent with the estimated trends of penta-, octa- and deca-BDE contained in in-use products based on domestic demand for PBDEs in Japan and product lifespan. Seasonal patterns were opposite for light congeners (BDE-47 and -99), which increased with temperature, and heavy congeners (BDE-183, and -209), which decreased with temperature. Temperature-dependent emission (evaporation) for light congeners and temperature-independent emission (abrasion) for heavy congeners, coupled with seasonality of atmospheric boundary layer height, might explain these seasonal patterns. Human population density showed a positive correlation with all PBDE congener concentrations, whereas PBDEs showed negative correlation with rainfall rate.