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This study compares the performance of 12 regional chemical transport models (CTMs) from the third phase of the Model Inter-Comparison Study for Asia (MICS-Asia III) on simulating the particulate matter (PM) over East Asia (EA) in 2010. The participating models include the Weather Research and Forecasting model coupled with Community Multiscale Air Quality (WRF-CMAQ; v4.7.1 and v5.0.2), the Regional Atmospheric Modeling System coupled with CMAQ (RAMS-CMAQ; v4.7.1 and v5.0.2), the Weather Research and Forecasting model coupled with chemistry (WRF-Chem; v3.6.1 and v3.7.1), Goddard Earth Observing System coupled with chemistry (GEOS-Chem), a non-hydrostatic model coupled with chemistry (NHM-Chem), the Nested Air Quality Prediction Modeling System (NAQPMS) and the NASA-Unified WRF (NU-WRF). This study investigates three model processes as the possible reasons for different model performances on PM. (1) Models perform very differently in the gas–particle conversion of sulfur (S) and oxidized nitrogen (N). The model differences in sulfur oxidation ratio (50 %) are of the same magnitude as that in SO42- concentrations. The gas–particle conversion is one of the main reasons for different model performances on fine mode PM. (2) Models without dust emission modules can perform well on PM10 at non-dust-affected sites but largely underestimate (up to 50 %) the PM10 concentrations at dust sites. The implementation of dust emission modules in the models has largely improved the model accuracies at dust sites (reduce model bias to −20 %). However, both the magnitude and distribution of dust pollution are not fully captured. (3) The amounts of modeled depositions vary among models by 75 %, 39 %, 21 % and 38 % for S wet, S dry, N wet and N dry depositions, respectively. Large inter-model differences are found in the washout ratios of wet deposition (at most 170 % in India) and dry deposition velocities (generally 0.3–2 cm s−1 differences over inland regions).

BackgroundThe COVID-19 pandemic situation has been changing drastically worldwide due to the continuous appearance of SARS-CoV-2 variants and the roll-out of mass vaccination. Periodic cross-sectional studies during the surge of COVID-19 cases is essential to elucidate the pandemic situation.MethodsSera of 1,000 individuals who underwent a health check-up in Hyogo Prefecture Health Promotion Association clinics in Japan were collected in August and December 2021. Antibodies against SARS-CoV-2 N and S antigens were detected in the sera by an electrochemiluminescence immunoassay (ECLIA) and an enzyme-linked immunosorbent assay (ELISA), respectively. The sera’s neutralization activities for the conventional SARS-CoV-2 (D614G), Delta, and Omicron variants were measured.ResultsThe seropositive rates for the antibody against N antigen were 2.1% and 3.9% in August and December 2021 respectively, demonstrating a Delta variant endemic during that time; the actual infection rate was approximately twofold higher than the rate estimated based on the polymerase chain reaction (PCR)-based diagnosis. The anti-S seropositive rate was 38.7% in August and it reached 90.8% in December, in concordance with the vaccination rate in Japan. In the December cohort, 78.7% of the sera showed neutralizing activity against the Delta variant, whereas that against the Omicron was much lower at 36.6%.ConclusionsThese analyses revealed that herd immunity against SARS-CoV-2 including the Delta variant was established in December 2021, leading to convergence of the variants. The low neutralizing activity against the Omicron variant suggests the need for the further promotion of the prompt three-dose vaccination to overcome this variant’s imminent 6th wave in Japan.SummarySeroepidemiologic study of COVID-19 on December 2021 in Japan showed neutralizing antibodies for Delta were 78.7%, indicating the acquisition of herd immunity by mass vaccination leading to convergence while those for Omicron were only 36.6%, indicating need of booster vaccination.

The situation of the COVID-19 pandemic in Japan is drastically changing in the 2ndyear, 2021, due to the appearance of SARS-CoV-2 variants of concern and the roll-out of mass vaccination. In addition to PCR diagnosis, periodic seroepidemiologic surveillance is important to analyze the epidemic situation. In this study, we analyzed the rate of seropositivity for the SARS-CoV-2 N and S antigens in Hyogo prefecture, Japan in August 2021. Sera collected from people who received a health check-up in a clinic of the Hyogo Prefecture Health Promotion Association were subjected to analysis of reactivity to the SARS-CoV-2 N and S antigens by electrochemiluminescence immunoassay (ECLIA) and enzyme-linked immunosorbent assay (ELISA), respectively. For a total 1,000 sera, the positive rates to N and S antigens were 2.1% and 38.7%, respectively. The infectious rate estimated by serological analysis based on the presence of the anti-N antibody was 2.5-fold higher than the value reported based on PCR-based analysis, and it increased five-fold compared to the rate determined by our previous seroepidemiologic study in October, 2020. The anti-S positive rate was almost consistent with the vaccination rate in this area. The observed high anti-S antibody level in the seropositive population may indicate that the mass vaccination in Japan is being performed smoothly at this time point, although the infectious rate has also increased.

Despite the significant progress in improving chemical transport models (CTMs), applications of these modeling endeavors are still subject to large and complex model uncertainty. The Model Inter-Comparison Study for Asia III (MICS-Asia III) has provided the opportunity to assess the capability and uncertainty of current CTMs in East Asian applications. In this study, we have evaluated the multi-model simulations of nitrogen dioxide (NO2), carbon monoxide (CO) and ammonia (NH3) over China under the framework of MICS-Asia III. A total of 13 modeling results, provided by several independent groups from different countries and regions, were used in this study. Most of these models used the same modeling domain with a horizontal resolution of 45 km and were driven by common emission inventories and meteorological inputs. New observations over the North China Plain (NCP) and Pearl River Delta (PRD) regions were also available in MICS-Asia III, allowing the model evaluations over highly industrialized regions. The evaluation results show that most models captured the monthly and spatial patterns of NO2 concentrations in the NCP region well, though NO2 levels were slightly underestimated. Relatively poor performance in NO2 simulations was found in the PRD region, with larger root-mean-square error and lower spatial correlation coefficients, which may be related to the coarse resolution or inappropriate spatial allocations of the emission inventories in the PRD region. All models significantly underpredicted CO concentrations in both the NCP and PRD regions, with annual mean concentrations that were 65.4 % and 61.4 % underestimated by the ensemble mean. Such large underestimations suggest that CO emissions might be underestimated in the current emission inventory. In contrast to the good skills for simulating the monthly variations in NO2 and CO concentrations, all models failed to reproduce the observed monthly variations in NH3 concentrations in the NCP region. Most models mismatched the observed peak in July and showed negative correlation coefficients with the observations, which may be closely related to the uncertainty in the monthly variations in NH3 emissions and the NH3 gas–aerosol partitioning. Finally, model intercomparisons have been conducted to quantify the impacts of model uncertainty on the simulations of these gases, which are shown to increase with the reactivity of species. Models contained more uncertainty in the NH3 simulations. This suggests that for some highly active and/or short-lived primary pollutants, like NH3, model uncertainty can also take a great part in the forecast uncertainty in addition to the emission uncertainty. Based on these results, some recommendations are made for future studies.

Asia has attracted research attention because it has the highest anthropogenic emissions in the world, and the Model Inter-Comparison Study for Asia (MICS-Asia) Phase III was carried out to foster our understanding on the status of air quality over Asia. This study analyzed wet deposition in Southeast Asian countries (Myanmar, Thailand, Lao People's Democratic Republic (PDR), Cambodia, Vietnam, the Philippines, Malaysia, and Indonesia) with the aim of providing insights into the seasonal variation of wet deposition. Southeast Asia was not fully considered in MICS-Asia Phase II due to a lack of observational data; however, the analysis period of MICS-Asia III, namely, the year 2010, is covered by ground observations of the Acid Deposition Monitoring Network in East Asia (EANET), and the coordinated simulation domain was extended to cover these observation sites. The analyzed species are wet depositions of S (sulfate aerosol, sulfur dioxide (SO2), and sulfuric acid (H2SO4)), N (nitrate aerosol, nitrogen monoxide (NO), nitrogen dioxide (NO2), and nitric acid (HNO3)), and A (ammonium aerosol and ammonia (NH3)). The wet deposition simulated with seven models driven by unified meteorological model in MICS-Asia III was used with the ensemble approach, which effectively modulates the differences in performance among models. By comparison with EANET observations, although the seven models generally captured the wet depositions of S, N, and A, there were difficulties capturing these in some cases. This failure of models is considered to be related to the difficulty in capturing the precipitation in Southeast Asia, especially during the dry and wet seasons. To overcome this, a precipitation-adjusted approach which scaling the modeled precipitation to the observed value was applied, and it was demonstrated that the model performance was improved. Satellite measurements were also used to adjust for precipitation data, which worked well to account for spatio-and-temporal precipitation patterns, especially in the dry season. As the statistical scores were mostly improved by this adjustment, the estimation of wet deposition with precipitation adjustment was considered to be superior. To utilize satellite measurements, the spatial distribution of wet deposition was revised. Based on this revision, it was found that Vietnam, Malaysia, and Indonesia were upward-corrected and Myanmar, Thailand, Lao PDR, Cambodia, and the Philippines were downward-corrected; these corrections were up to ±40 %. The improved accuracy of precipitation amount was key to estimating wet deposition in this study. These results suggest that the precipitation-adjusted approach has the potential to obtain accurate estimates of wet deposition through the fusion of models and observations.

Many attempts to reduce radiation fields for intracranial germ cell tumors (iGCTs) remain unsuccessful. To assess the possibility of reduction, we analyzed registry data of 57 patients who mostly underwent local irradiation for iGCTs between 1997 and 2006. The recommended treatment for pure germinomas (PGNs) included 3 courses of cisplatin and etoposide followed by 24 Gy local irradiation. Intensified chemotherapy using a combination of cyclophosphamide and intrathecal methotrexate was recommended for human chorionic gonadotropin-producing germinomas (hCG-GNs) and nongerminomatous germ cell tumors (NGGCTs); both received 50.4 Gy local irradiation. High-dose chemotherapy was only administered for residual NGGCTs after chemoradiotherapy. Craniospinal irradiation was recommended only in metastatic cases. During the median follow-up of 114.8 months, 8 of 9 relapses from 24 PGNs occurred outside irradiation fields, with a 5-year progression-free survival (5-year PFS) of 75%±8.8%. Conversely, no recurrences occurred from 11 hCG-GNs, with a 5-year PFS of 100%. Eleven of 22 patients with NGGCTs received high-dose chemotherapy; the 5-year PFS was 81.3%±8.4%; 2 of 3 relapses occurred in the spinal cord. Thus, local irradiation for PGNs was insufficient without treatment intensification. The introduction of intensified chemotherapy improved outcomes of both patients with hCG-GNs and NGGCTs. However, the contributions of either modality remained unclear.

In order to clarify the causes of variability among the model outputs for surface ozone in the Model Intercomparison Study Asia Phase III (MICS-Asia III), three regional models, CMAQ v.5.0.2, CMAQ v.4.7.1, and NAQPMS (abbreviated as NAQM in this paper), have been selected. Detailed analyses of monthly averaged diurnal variation have been performed for selected grids covering the metropolitan areas of Beijing and Tokyo and at a remote oceanic site, Oki. The chemical reaction mechanism, SAPRC99, used in the CMAQ models tended to give a higher net chemical ozone production than CBM-Z used in NAQM, agreeing with previous studies. Inclusion of the heterogeneous “renoxification” reaction of HNO3 (on soot surface)→NO+NO2 only in NAQM would give a higher NO concentration resulting in a better agreement with observational data for NO and nighttime O3 mixing ratios. In addition to chemical processes, the difference in the vertical transport of O3 was found to affect the simulated results significantly. Particularly, the increase in downward O3 flux from the upper layer to the surface after dawn was found to be substantially different among the models. Larger early morning vertical transport of O3 simulated by CMAQ 5.0.2 is thought to be the reason for higher daytime O3 in July in this model. All three models overestimated the daytime ozone by ca. 20 ppbv at the remote site Oki in July, where in situ photochemical activity is minimal.

In order to identify the causes of overestimate of the surface-level O3 mixing ratio simulated by three regional chemical-transport models, namely NAQPMS v.3 (abbreviated as NAQM in this paper), CMAQ v.5.0.2, and CMAQ v.4.7.1, compared to the EANET observational data at a marine remote site at Oki in July 2010 in the context of MICS-Asia III, analyses of hourly data of O3 mixing ratios and net ozone production were made. In addition to Oki, model-simulated and observational data for two other EANET marine sites, Hedo and Ogasawara, were also examined. Three factors, i.e., long-range transport from the continent, in-situ photochemical formation, and dry deposition of O3 on seawater have been found to contribute to the overestimate by these regional models at Oki. The calculated O3 mixing ratios during long-range transport from the continent were much higher for all the three models than those of the observation. In-situ photochemical formation, demonstrated by a distinct diurnal variation which was not discerned in the observational data, was seen in the simulated data of all the three models and ascribed to the virtual transport of NOx from the southern urban areas of the main island of Japan. At Hedo and Ogasawara overestimate of O3 in oceanic air mass was found for CMAQ v.5.0.2 and v. 4.7.1, while good agreement was obtained by NAQM. The overestimate by CMAQ models were inferred to be due to the use of too small dry deposition rate of O3 compared to NAQM in the Northwestern Pacific. However, the dry deposition velocity of O3 in the Bohai Bay and the Yellow Sea has been assumed to be comparable to that of the open ocean in all the three models, which could have resulted in the overestimate of O3 mixing ratios in this area and also in the long-range transport of O3 from the continent to Oki. A higher value of dry deposition velocity in this marine area is expected considering the higher content of organics in the surface sea layer brought by rivers and atmospheric wet deposition. Empirical measurements of the dry deposition flux in this area is highly recommended, since it would affect the simulated mixing ratios in the down-wind region and the estimate of transboundary transport of ozone from the continent to the Pacific rim region.

There are very few reports in the literature associating in hydrocephalus in osteopetrosis. As a complication of shunt procedure, there are two reports on shunt malfunction due to osseous overgrowth at the burr hole in patients with osteopetrosis. We herein report a case of osteopetrosis with hydrocephalus that was successfully treated with endoscopic third ventriculostomy (ETV). At 5 months of age, a male patient presented with developmental delay. Head computed tomography (CT) demonstrated triventricular hydrocephalus with a cerebellar tonsillar herniation. At 7 months of age, he underwent suboccipital decompression with decompression of the foramen magnum. The hydrocephalus did not improve postoperatively, and the patient was transferred to our hospital. At 12 months of age, the hydrocephalus was successfully treated with ETV. The postoperative period was uneventful. Postoperative CT demonstrated an improvement in the ventricle size. The etiology of hydrocephalus in osteopetrosis is not completely understood; however, there have been several reports in which ETV was effective. ETV should be considered the treatment of choice for hydrocephalus in osteopetrosis, as it avoids the characteristic shunt complications that can occur in patients with osteopetrosis.

Chemical transport models are useful tools for evaluating source contributions and health impacts of PM2.5 in the atmosphere. We recently found that concentrations of PM2.5 compounds over Japan were much better reproduced by a volatility basis set model with an enhanced dry deposition velocity of HNO3 and NH3 compared with a two-product yield model. In this study, we evaluated the sensitivities to organic aerosol models of the simulated source contributions to PM2.5 concentrations and of PM2.5-related mortality. Overall, the simulated source contributions to PM2.5 were similar between the two models. However, because of the improvements associated with the volatility basis set model, the contributions of ammonia sources decreased, particularly in winter and spring, and contributions of biogenic and stationary evaporative sources increased in spring and summer. The improved model estimated that emission sources in Japan contributed 35%–48% of the PM2.5-related mortality in Japan. These values were higher t...

An in situ silver decoration technique using a light microscope was developed. Hydrogen was introduced from the bottom surface of an annealed pure iron specimen, and its top surface was covered with a chemical solution containing silver ions. Samples were exposed for sufficient time for hydrogen permeation to occur from the back to the top surface. The resultant in situ silver decoration visualized that the hydrogen flux through low-angle grain boundaries is lower than that observed at high-angle grain boundaries. The in situ silver decoration technique can be used for kinetic analysis of solute hydrogen in ferritic iron and steels.

Atmospheric nitrogen deposition in China has attracted huge public attention in recently years due to the increasing anthropogenic emission of reactive nitrogen (Nr) and its impacts on the terrestrial and aquatic ecosystems. However, limited long-term and multi-site measurements have restrained the understanding on the mechanism of the Nr deposition as well as the chemical transport model (CTM) improvement. In this study, the performance of the simulated wet and dry deposition for different Nr species, i.e., particulate NO3− and NH4+, gaseous NOx, HNO3 and NH3, have been conducted using the framework of Model Inter-Comparison Study for Asia (MICS-Asia) phase III. Nine Models, including 5 WRF-CAMQ models, 2 self-developed regional models, a global model and a RAMS-CMAQ model, have been selected for the comparison. For wet depositions, observation data from 83 measurement sites of EANET, CREN, CAUDN, NADMN and DEE of China have been collected and normalized to compare with model results. In general, most models showed the consistent spatial and temporal variation of both oxidized N (Nox) and reduced N (Nrd) wet depositions in China with the NME around at 50 %, which is lower than the value of 70 % based on EANET observation over Asia. Both the ratio of wet or dry deposition to the total inorganic N deposition (TIN) and the ratios of TIN to their emissions have shown the consistent results with the NNDMN estimations. The performance of ensemble results (ENM) was further assessed with the measurement from satellite. In different regions of China, the results showed that the simulated Nox wet deposition was overestimated in North East China (NE) but underestimated in south of China (SE+SW), while the Nrd wet deposition was underpredicted in all regions by all models. The deposition of Nox have large uncertainties than the Nrd especially in North China (NC), indicating chemical reaction process is one of the most importance factors that affecting the model performance. Compared to Critical load (CL) value, the Nr deposition in NC, SE and SW reached or exceeded the reported CL value and exerted serious ecological impacts. The control of Nrd in NC and SW and Nox in SE would be effective to mitigate the TIN deposition in these regions. More interestingly, the Nr deposition in Tibet plateau with the high ratio of TIN/emission (~3.0), indicating a significant import from outside should be focused in the future due to its climatical influence to the sensitive ecosystem in whole China.

The Model Inter-Comparison Study for Asia (MICS-Asia) Phase III was conducted to promote understanding of regional air quality and climate change in Asia, which have received growing attention due to the huge amount of anthropogenic emissions worldwide. This study provides an overview of acid depositions. Specifically, dry and wet depositions of the following species were analyzed: S (sulfate aerosol, sulfur dioxide (SO2), and sulfuric acid (H2SO4)), N (nitrate aerosol, nitrogen monoxide (NO), nitrogen dioxide (NO2), and nitric acid (HNO3)), and A (ammonium aerosol and ammonia (NH3)). The wet deposition simulated by a total of nine models was analyzed and evaluated using ground observation data from the Acid Deposition Monitoring Network in East Asia (EANET). In this Phase III study, the number of observation sites was increased to 54 from 37 in the Phase II study, and Southeast Asian countries were newly added. Additionally, whereas the analysis period was limited to representative months of each season in MICS-Asia Phase II, this Phase III study analyzed the full year of 2010. The scope of this overview mainly focuses on the annual accumulated depositions. In general, models can capture the observed wet depositions over Asia but underestimate the wet deposition of S and A and show large differences in the wet deposition of N. Furthermore, the ratio of wet deposition to the total deposition (the sum of dry and wet deposition) was investigated in order to understand the role of important processes in the total deposition. The general dominance of wet deposition over Asia and attributions from dry deposition over land were consistently found in all models. Then, total deposition maps over 13 countries participating in EANET were produced, and the balance between deposition and anthropogenic emissions was calculated. Excesses of deposition, rather than of anthropogenic emissions, were found over Japan, North Asia, and Southeast Asia, indicating the possibility of long-range transport within and outside Asia, as well as other emission sources. To improve the ability of models to capture the observed wet deposition, two approaches were attempted, namely, ensemble and precipitation adjustment. The ensemble approach was effective at modulating the differences in performance among models, and the precipitation-adjusted approach demonstrated that the model performance for precipitation played a key role in better simulating wet deposition. Finally, the lessons learned from this Phase III study and future perspectives for Phase IV are summarized.

This study compares the performances of twelve regional chemical transport models (CTM) from the third phase of Model Inter-Comparison Study for Asia (MICS-Asia III) on simulating the particulate matter (PM) over East Asia (EA) in 2010. The participating models include WRF-CMAQ (v4.7.1 and v5.0.2), WRF-Chem (v3.6.1 and v3.7.1), GEOS-Chem, NHM-Chem, NAQPMS and NU-WRF. Evaluations with ground measurements and satellite data show that the mean biases of multi-model mean (MMM) are −25 µg m−3 (−30 %), −7 µg m−3 (−15 %). −0.7 µg m−3 (−19 %), −0.05 µg m−3 (−3 %) and 0.1 µg m−3 (12 %) for surface PM10, PM2.5, SO42−, NO3− and NH4+ concentrations, respectively. This study investigates four model processes as the possible reasons for different model performances on PM: (1) Using different natural emissions (i.e. dust and sea-salt emissions) brings upmost 0.25 µg m−3 (70 %) of inter-model differences to domain-average black carbon concentrations at surface layer and 756 ppb (22 %) of inter-model differences to domain-average CO column. Adopting different initial/boundary conditions results in 10–20 % differences in PM concentrations in the center of the simulation domain. (2) Models perform very differently in the gas-particle conversion of sulphur (S) and oxidized nitrogen (N). The model differences in sulphur oxidation ratio (50 %) is of the same magnitude as that in SO42− concentrations. The gas-particle conversion is one the main reasons for different model performances on fine mode PM. (3) Models without dust emissions/modules can perform well on PM10 at non-dust-affected sites, but largely underestimate (upmost 50 %) the PM10 concentrations at dust sites. The implementation of dust emissions/modules in models has largely improved the model accuracies at dust sites (reduce model bias to −20 %). However, both the magnitudes and distributions of dust pollutions are not fully captured. (4) The amounts of modelled depositions vary among models by 75 %, 39 %, 21 % and 38 % for S wet, S dry, N wet and N dry depositions, respectively. Large inter-model differences are found in the washout ratios of wet deposition (at most 170 % in India) and dry deposition velocities (general 0.3–2 cm s−1 differences over inland regions). This study investigates the reasons for different model performances on PM over EA and offers suggestions for future model development.

Despite significant progress in improving chemical transport models (CTMs), applications of these modeling endeavours are still subject to the large and complex model uncertainty. Model Inter-Comparison Study for Asia III (MICS-Asia III) provides the opportunity to assess the capability and uncertainty of current CTMs in East Asia applications. In this study, we evaluated the multi-model simulations of nitrogen dioxide (NO2), carbon monoxide (CO) and ammonia (NH3) over China under the framework of MICS-Asia III. Compared with MICS-Asia II, modeling results were provided by a larger number of independent groups from different countries/regions and covered a longer period of time (one-full year). Furthermore, most of these groups used a common emission inventory, common meteorological inputs, and the same modeling domain and horizontal resolutions. New observations over North China Plain (NCP) and Peral River Delta (PRD) were also available in MICS-Asia III, allowing model evaluations over highly industrialized regions. The results show that most models well captured the monthly and spatial patterns of NO2 in NCP though NO2 levels were slightly underestimated. Relatively poor performance in NO2 simulations was found in PRD with larger root mean square error and lower spatial correlation coefficients, possibly due to the relative coarse model resolutions. All models significantly underpredicted CO concentrations both in NCP and PRD, with annual mean concentrations 65.4 % and 61.4 % underestimated by the ensemble mean respectively. Such large underestimations suggest that CO emissions might be underestimated in current emission inventory. In contrast to the good skills in simulating the monthly variations of NO2 and CO concentrations, all models failed to reproduce the observed monthly variations of NH3 concentrations in NCP. Most models mismatched the observed peak in July and showed negative correlation coefficients with observations, which may be closely related to the uncertainty in the monthly variations of NH3 emissions and the NH3 gas-aerosol partitioning. Finally, inter-comparisons of these model results were conducted to quantify the impacts of model uncertainty on the simulations of these gases, which are shown increase with the reactivity of species. Models contained more uncertainty in the NH3 simulations. This suggests that for some highly active and/or short-lived primary pollutants, like NH3, model uncertainty can also take a great part in the forecast uncertainty in addition to the emission uncertainty. Based on these results, some recommendations are made for future studies.

Various treatment modalities have been used in the management of chronic subdural hematoma and subdural hygroma (CSDH/SDHy) in children. However, few studies have examined burr-hole craniotomy without continuous drainage in such cases. Here, we retrospectively evaluated the efficacy and safety of burr-hole craniotomy without continuous drainage for CSDH/SDHy in children under 2 years old. We also aimed to determine the predictors of CSDH/SDHy recurrence. We conducted a retrospective chart review of 25 children under 2 years old who underwent burr-hole craniotomy without continuous drainage for CSDH/SDHy at a pediatric teaching hospital over a 10-year period. We analyzed the relationship between CSDH/SDHy recurrence and factors such as abusive head trauma, laterality of CSDH/SDHy, and subdural fluid collection type (hematoma or hygroma). CSDH/SDHy recurred in 5 of the 25 patients (20 %), requiring a second operation at an average of 0.92 ± 1.12 months after the initial procedure. The mean follow-up period was 25.1 ± 28.6 months. There were no complications related to either operation. None of the assessed factors were statistically associated with recurrence. Burr-hole craniotomy without continuous drainage for CSDH/SDHy appears safe in children aged under 2 years and results in a relatively low recurrence rate. No predictors of CSDH/SDHy recurrence were identified. Advantages of this method include avoiding external subdural drainage-related complications. However, burr-hole drainage may be more effective for CSDH, which our data suggests is more likely to recur than SDHy, providing the procedure is performed with specific efforts to reduce complications.

The hydrogen distribution in an austenite–martensite dual-phase steel was investigated using silver decoration and scanning Kelvin probe force microscopy. The silver decoration technique optimized for spacial resolution reveals interfacial segregation of hydrogen along the plate-type martensite–martensite grain boundaries. In addition, the scanning Kelvin probe force microscopy kinetically elucidates that hydrogen preferentially diffused out from the martensite–martensite grain boundaries. These preferential sites of hydrogen desorption correspond to the regions of hydrogen-assisted damage.

In this study, the results for nitrate (NO3&minus, ) aerosol during winter from the first-phase model inter-comparison study of Japan&rsquo, s Study for Reference Air Quality Modeling (J-STREAM) were analyzed. To investigate the models&rsquo, external and internal settings, the results were limited to Community Multiscale Air Quality (CMAQ) models. All submitted models generally underestimated NO3&minus, over the urban areas in Japan (e.g., Osaka, Nagoya, and Tokyo), however, some model settings showed distinct behavior. The differences due to the model external settings were larger than the model internal settings. Emissions were an important factor, and emissions configured with lower NOx emissions and higher NH3 emissions led to a higher NO3&minus, concentration as the NH3 was consumed under NH3-rich conditions. The model internal settings of the chemical mechanisms caused differences over China, and this could affect western Japan, however, the difference over Tokyo was lower. To obtain a higher NO3&minus, concentration over the urban areas in Japan, the selection of the HONO option for the heterogenous reaction and the inline calculation of photolysis was desired. For future studies, the external settings of the boundary condition and the meteorological field require further investigation.

Long-term ozone (O3) and nitric oxide (NOx) from fourteen state-of-the-art chemical transport models are evaluated and intercompared to ozone observations in East Asia, within the framework of the Model Inter-Comparison Study for ASIA phase III (MICS-ASIA III), designed to evaluate the capabilities and uncertainties of current chemical transport models (CTMs) simulations in Asia and provide multi-model estimates of pollution distributions. These models were run by fourteen independent groups in China, Japan, Korea, United States of America and other countries/regions. Compared with MICS-ASIAII, the evaluation against observations were extended to be one-full year in China and the western Pacific Rim from four months and the western Pacific Rim. Potential causes of the discrepancies between model results and observation have also been investigated by assessing the PBL heights, emission fluxes, dry deposition, O3-NOx relationships and vertical profiles among models in this study. In general, the model skills for O3 varied largely with region and seasons. Most models captured the key pattern of monthly and diurnal surface O3 and its precursors in North China Plain, Yangtze River Delta and western Pacific rim, but failed in Peral River Delta of China. A significant overestimation of surface ozone was found in May–September/October and January–May over North China Plain, western Pacific rim and Peral River Delta of China, respectively. A large intermodel variability of O3 existed in all subregions over East Asia in this study, which was caused by the internal parameterizations of chemistry, dry deposition and vertical mixing of models, even though the native schemes in models are similar. Ensemble average of 13 models on O3 did not always exhibit a superior performance compared to certain individual model, in contrast to its superiority in Europe. This suggested that the spread of ensemble-model values hadn't represented all uncertainties of ozone or most models in MICS-ASIAIII missed key processes. Compared with the previous phase of MICS-ASIA（MICS-ASIAII, this study improved the performance of ozone in March at Japan sites. But it predicted too enhanced surface O3 concentrations at western Japan in July, which has not been found in MICS-ASIAII. Major challenges still remain with regards to recognizing the sources of bias in surface O3 over East Asia in CTMs.

A multi-model ensemble of Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) simulations are used to study the atmospheric oxidized nitrogen (NOy) deposition over East Asia under climate and emission changes projected for the future. Both dry and wet NOy deposition shows significant decreases in the 2100s under RCP 4.5 and RCP 8.5, primarily due to large anthropogenic emission reduction over both land and sea. However, in the near future of the 2030s, both dry and wet NOy deposition increases significantly due to continued increase in emissions. The individual effect of climate or emission changes on dry and wet NOy deposition is also investigated. The impact of climate change on dry NOy deposition is relatively minor, but the effect on wet deposition, primarily caused by changes in precipitation, is much higher. For example, over the East China Sea, wet NOy deposition increases significantly in summer due to climate change by the end of this century under RCP 8.5, which may subsequently enhance marine primary production. Over the coastal seas of China, as the transport of NOy from land becomes weaker due to the decrease of anthropogenic emissions, the effect of ship emission and lightning emission becomes more important. On average, seasonal mean total NOy deposition is projected to be enhanced by 24–48 % and 3 %–37 % over Yellow Sea and East China Sea, respectively, by the end of this century. Therefore, continued control of both anthropogenic emission over land and ship emissions may reduce NOy deposition to the Chinese coastal seas.

In order to clarify the cause of variability among the model outputs for surface ozone in the Model Intercomparison Study Asia Phase III (MICS-Asia III), three regional models, CMAQ v.5.0.2, CMAQ v.4.7.1 and NAQPMS (abbreviated as NAQM in this paper) have been selected. The detailed analyses have been made for monthly averaged diurnal variation for select grids covering metropolitan area of Beijing and Tokyo, and at a remote oceanic site, Oki. The chemical reaction mechanism, SAPRC99 used in the CMAQ models tends to give higher net chemical ozone production than CBM-Z used in NAQM agreeing with previous studies. Inclusion of heterogeneous “renoxification” reaction of HNO3 (on soot) → NO + NO2 only in NAQM is supposed to give higher NO concentration to give better agreement with observational data for NO and nighttime O3 mixing ratios. In addition to chemistry, the difference in vertical transport of O3 was found to affect the simulated results significantly. Particularly, the increase in downward flux of O3 from upper layer to the surface after the dawn is found to be substantially different among the models. Larger early morning vertical transport of O3 by CMAQ 5.0.2 would be the reason for higher daytime O3 by this model in July. All the three models overestimate the daytime ozone by ca. 20 ppbv at the remote site Oki in July, where in situ photochemical activity is minimal.

We introduce a perceptual video quality driven video encoding solution for optimized adaptive streaming. By using multiple bitrate/resolution encoding like MPEG-DASH, video streaming services can deliver the best video stream to a client, under the conditions of the client's available bandwidth and viewing device capability. However, conventional fixed encoding recipes (i.e., resolution-bitrate pairs) suffer from many problems, such as improper resolution selection and stream redundancy. To avoid these problems, we propose a novel video coding method, which generates multiple representations with constant JustNoticeable Difference (JND) interval. For this purpose, we developed a JND scale estimator using Support Vector Regression (SVR), and designed a pre-encoder which outputs an encoding recipe with constant JND interval in an adaptive manner to input video.

For understanding the underlying hydrogen embrittlement mechanism in transformation-induced plasticity steels, the process of damage evolution in a model austenite/martensite dual-phase microstructure following hydrogenation was investigated through multi-scale electron channelling contrast imaging and in situ optical microscopy. Localized diffusible hydrogen in martensite causes cracking through two mechanisms: (1) interaction between {1 1 0}M localized slip and {1 1 2}M twin and (2) cracking of martensite–martensite grain interfaces. The former resulted in nanovoids along the {1 1 2}M twin. The coalescence of the nanovoids generated plate-like microvoids. The latter caused shear localization on the specific plane where the crack along the martensite/martensite boundary exists, which led to additional martensite/martensite boundary cracking.

The emissions of NO x and CO 2 in East Asia (Northeast and Southeast Asia) contribute more than 30% of the global total since 2008, and consequently the control of air pollutants and CO 2 alleviating regional air pollution and global climate change is of great concern of not only in this region but also worldwide. In order to arrive at a rational view of the short-lived climate pollutants (SLCPs) co-control approach in East Asia, the effectiveness of the reduction of NO x /NMVOC and CH 4 emissions for the reduction of tropospheric O 3 has been evaluated by individual and simultaneous 50%-reduction of the emissions in Northeast Asia (NEA) using both a global chemical climate model (CHASER/SPRINTARS-MIROC), and a regional chemical transport model (WRF-CMAQ). The simultaneous reduction of NO x /NMVOC and CH 4 emissions was found to reduce the regional concentration of surface O 3 in NEA, and globally averaged net radiative forcing most effectively. Global mean RF and regional air quality change were also evaluated for the climate stabilization scenario (“450-ppm”), and climate stabilization with additional air pollution mitigation strengthened scenario (“450-ppm-cntr”) developed in IIASA with the aid of GAINS model. In the 450 ppm-cntr scenario, emissions of NO x NMVOC, BC and OC were further reduced respectively, for East Asia from the emissions in 450 ppm. The improvement of air quality as well as the mitigation of climate change would grant to the basis of the SLCP co-control approach in East Asia.