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Understanding the systematic characteristics of tropical cyclones (TCs) represented in global climate models (GCMs) is important for reliable climate change impact assessments. The atmospheric GCM (AGCM) and ocean wave models were coupled by incorporating the wave-dependent momentum flux. Systematic impacts of wave-dependent momentum flux on TC characteristics were estimated by analyzing 100 historical TCs that occurred in the western North Pacific Ocean. Wave-dependent momentum flux parameterization considering wind and wave direction misalignment was used for assessing the wave–atmosphere interaction. The larger the wave age and misalignment are, the larger the drag coefficient is. The drag coefficient at the left-hand side of the TC was enhanced by the wave condition. It was found that the wave-dependent momentum flux did not have any impact on peak TC intensity. On the other hand, the wave-dependent momentum flux showed a significant impact on TC development during the early development stage. Although systematic differences in TC intensity at most developed stages were not detected, systematic differences in TC tracks between experiments were observed. The TC tracks of the wave-coupled AGCM tend to pass in a relatively eastward direction in comparison with those from the uncoupled AGCM. This is because the wave-dependent momentum flux in the coupled AGCM altered the environmental steering flow and the smaller beta effect of smaller TC at the early developing stage. Systematic differences in TC tracks have significant impacts on climate change assessments, such as extreme sea level changes in coastal regions due to climate change.

Pilocytic astrocytoma (PA) is a circumscribed low-grade astrocytic glioma, generally considered to be associated with a good prognosis. However, a subset of PA patients shows unfavorable outcomes. In this study, we retrospectively reviewed PA patients and performed further molecular analysis, such as DNA methylation profiling, to identify prognostic factors.We analyzed 29 histologically-confirmed PA patients from a single center from 2002 to 2021 and conducted integrated molecular analyses among elderly PA patients since age was an independent prognostic factor for poor outcomes.The median age at diagnosis was 14 years (range 3-82 years) and 4 patients (14%) were elderly (patients ≥ 60 years old). Age over 60 was associated with poor progression-free survival and overall survival. We performed DNA methylation analysis on 2 of the 4 elderly patients. Both cases were histologically diagnosed as PA, but DNA methylation profiling revealed one as high-grade astrocytoma with piloid features (all methylation class scores were below 0.3 in both v11b4 and v12.5) and the other as glioblastoma, IDH-wildtype (score was over 0.5 in both v11b4 and v12.5), using the German Cancer Research Center methylation profiling classifiers and t-SNE analysis.Elderly patients with PA morphology showed unfavorable outcomes in this cohort. In those patients, further molecular analysis and DNA methylation profiling revealed the possibility of high-grade astrocytic tumors, including newly defined entities.

Postoperative adhesion can lead to an increase in the number of surgeries required, longer operation times, and high medical costs, resulting in the quality of life of the patient being lowered. To address these clinical problems, we developed a surgical sealant with anti-adhesion properties for the prevention of postoperative adhesion following application to the large intestine surface. The developed sealant was composed of octyl (C8) group-modified Alaska pollock-derived gelatin (C8-ApGltn) and a poly(ethylene)glycol-based 4-armed crosslinker (4S-PEG) (C8-ApGltn/4S-PEG sealant). Hydrophobic modification of the ApGltn molecule with C8 groups effectively enhanced both the burst strength on the large intestine surface and the bulk modulus. An in vitro anti-adhesion test indicated that cured C8-ApGltn/4S-PEG sealant adhered to the large intestine surface showed low adhesive strength compared with commercial anti-adhesion film. Besides, cured C8-ApGltn/4S-PEG sealant effectively inhibited albumin permeation and penetration of L929 fibroblasts. In vivo experiments using a rat peritoneal anti-adhesion model showed that C8-ApGltn/4S-PEG sealant acted as a sealing barrier on the target cecum surface and also provided an anti-adhesion barrier to prevent postoperative adhesion between the peritoneum and cecum. C8-ApGltn/4S-PEG sealant showed sufficient cytocompatibility and biodegradability and therefore has potential for use in gastroenterological surgery.

We developed a new cranioplasty method that utilizes artificial bone made of ultra-high-molecular-weight polyethylene, with a wedge-shaped edge (UHMWPE Wing). This study shows the methods and data of case series and finite element analyses with the UHMWPE Wing. A circumferential wing was preoperatively designed for a custom-made artificial bone made of UHMWPE to achieve high fixed power and to minimize the usage of cranial implants. Here, we present 4 years of follow-up data and finite element analyses for patients treated with the UHMWPE Wing between February 2015 and February 2019. Eighteen consecutive patients underwent cranioplasty using our UHMWPE Wing design. There were no postoperative adverse events in 17 of the patients for at least 18 months. One case of hydrocephalus experienced screw loosening and graft uplift due to shunt malfunction. Placement of a ventriculo-peritoneal shunt immediately returned the artificial bone to normal position. Finite element analyses revealed that a model using the UHMWPE Wing had the highest withstand load and lowest deformation. This is the first report on the UHMWPE Wing method. This method may enable clinicians to minimize dead space and achieve high strength in cranioplasty.

Large-ensemble climate experiments were performed to simulate future climates for a + 1.5 K rise in the global mean surface air temperatures relative to preindustrial levels as a subset of the database for Policy Decision making for future climate change (d4PDF), using the Non-Hydrostatic Regional Climate Model (NHRCM) with 20 km grid spacing. Along with present climate, + 2 K and + 4 K experimental outputs from the d4PDF already available, we investigated responses of surface air temperature (SAT) and precipitation on regional scales over Japan to global warming. The reproducibility of the present climate experiment is satisfactory to investigate future changes in the Japanese climate, and dynamical downscaling from the global to the regional climate states improves the frequency of heavy daily precipitation. In the future, SAT over Japan rises linearly with and faster than the global mean SAT. The meridional contrast of SAT rises becomes more pronounced as global warming progresses. Winter precipitation decreases/increases linearly in the western/eastern Japan, reflected by weakening of future winter monsoons. Annual maximum daily precipitation (R1d) shows a closely linear increase with the global SAT rise, but annual precipitation is mostly unchanged. The global mean SAT change from + 1.5 to + 2 K enhances R1d by 2.7% over the Japanese Islands, although the increase of R1d varies by regions. The increase in R1d is 5% in northern Japan, where the SAT increases are greater than those in other regions.

Slow-moving tropical cyclones (TCs) can cause heavy rain because of their duration of influence. Combined with expected increase in rain rates associated with TCs in a warmer climate, there is growing interest in TC translation speed in the past and future. Here we present that a slowdown trend of the translation speed is not simulated for the period 1951–2011 based on historical model simulations. We also find that the annual-mean translation speed could increase under global warming. Although previous studies show large uncertainties in the future projections of TC characteristics, our model simulations show that the average TC translation speed at higher latitudes becomes smaller in a warmer climate, but the relative frequency of TCs at higher latitudes increases. Since the translation speed is much larger in the extratropics, the increase in the relative frequency of TCs at higher latitudes compensates the reduction of the translation speed there, leading to a global mean increase in TC translation speed., How the translation speed of tropical cyclones has changed in recent decades and will change in the future has been the subject of debate. Model results show that on average, they have not slowed down in the past, but despite a slowing of tropical cyclones at higher latitudes, a poleward shift in their mean track location causes a general speed up under high greenhouse gas emissions.

The performance of the Meteorological Research Institute-Atmospheric General Circulation model version 3.2 (MRI-AGCM3.2) in simulating precipitation is compared with that of global atmospheric models registerred to the sixth phase of the Coupled Model Intercomparison Project (CMIP6). The MRI-AGCM3.2 with the grid size of 20-km and 60-km and 36 CMIP6 models are forced with observed sea surface temperature for 20-year period from 1995 to 2014. The horizontal resolution of the MRI-AGCM3.2 is relatively finer than CMIP6 models. As for global domain, the reproducibility of MRI-AGCM3.2 models are better than or equal to CMIP6 models in simulating geographical distribution of annual precipitation and intense precipitation events. Models with higher horizontal resolution tend to be better than those with lower resolution in simulating global precipitation. As for East Asia, the performance of MRI-AGCM3.2 models are better than or equal to CMIP6 models in simulating summertime monthly precipitation and the seasonal march in the Japanese rainy season, and extreme precipitation events. Higher horizontal resolution models also tend to perform better than lower resolution models in simulating precipitation over East Asia. The advantage of models with higher horizontal resolution over those with lower resolution in reproducing precipitation is more evident over East Asia than over the globe.

There is growing evidence that the atmospheric dynamics of the Euro‐Atlantic sector during winter is driven in part by the presence of quasi‐persistent regimes. However, general circulation models typically struggle to simulate these with, for example, an overly weakly persistent blocking regime. Previous studies have showed that increased horizontal resolution can improve the regime structure of a model but have so far only considered a single model with only one ensemble member at each resolution, leaving open the possibility that this may be either coincidental or model dependent. We show that the improvement in regime structure due to increased resolution is robust across multiple models with multiple ensemble members. However, while the high‐resolution models have notably more tightly clustered data, other aspects of the regimes may not necessarily improve and are also subject to a large amount of sampling variability that typically requires at least three ensemble members to surmount., Key Points Climate models have difficulty representing Euro‐Atlantic regime structure correctlyIncreasing horizontal resolution improves the significance of regime clustering across multiple modelsSpatial patterns and persistence levels of regimes do not necessarily improve with increased resolution

This study examines long-term ensemble projections for historical and future climate conditions over 5,000 years using an atmospheric global circulation model. The future climate condition ...

We find that the use of Au substrate allows fast, self-limited WS2 monolayer growth using a simple sequential exposure pattern of low cost, low toxicity precursors, namely tungsten hexacarbonyl and dimethylsulfide (DMS). We use this model reaction system to fingerprint the technologically important metal organic chemical vapour deposition process by operando X-ray photoelectron spectroscopy (XPS) to address the current lack of understanding of the underlying fundamental growth mechanisms for WS2 and related transition metal dichalcogenides. Au effectively promotes the sulfidation of W with simple organosulfides, enabling WS2 growth with low DMS pressure (1 mbar) and a suppression of carbon contamination of as-grown WS2, which to date has been a major challenge with this precursor chemistry. Full WS2 coverage can be achieved by one exposure cycle of 10 minutes at 700 °C. We discuss our findings in the wider context of previous literature on heterogeneous catalysis, 2D crystal growth, and overlapping process technologies such as atomic layer deposition (ALD) and direct metal conversion, linking to future integrated manufacturing processes for transition metal dichalcogenide layers.

The mitogen-activated protein kinase (MAPK) pathways are involved in many cellular processes, including the development of fibrosis. Here, we examined the role of Sprouty-related EVH-1-domain-containing protein (Spred) 2, a negative regulator of the MAPK-ERK pathway, in the development of bleomycin (BLM)-induced pulmonary fibrosis (PF). Compared to WT mice, Spred2−/− mice developed milder PF with increased proliferation of bronchial epithelial cells. Spred2−/− lung epithelial cells or MLE-12 cells treated with spred2 siRNA proliferated faster than control cells in vitro. Spred2−/− and WT macrophages produced similar levels of TNFα and MCP-1 in response to BLM or lipopolysaccharide and myeloid cell-specific deletion of Spred2 in mice had no effect. Spred2−/− fibroblasts proliferated faster and produced similar levels of MCP-1 compared to WT fibroblasts. Spred2 mRNA was almost exclusively detected in bronchial epithelial cells of naïve WT mice and it accumulated in approximately 50% of cells with a characteristic of Clara cells, 14 days after BLM treatment. These results suggest that Spred2 is involved in the regulation of tissue repair after BLM-induced lung injury and increased proliferation of lung bronchial cells in Spred2−/− mice may contribute to faster tissue repair. Thus, Spred2 may present a new therapeutic target for the treatment of PF.

Future changes in tropical cyclone properties are an important component of climate change impacts and risk for many tropical and midlatitude countries. In this study we assess the performance of a multimodel ensemble of climate models, at resolutions ranging from 250 to 25 km. We use a common experimental design including both atmosphere‐only and coupled simulations run over the period 1950–2050, with two tracking algorithms applied uniformly across the models. There are overall improvements in tropical cyclone frequency, spatial distribution, and intensity in models at 25 km resolution, with several of them able to represent very intense storms. Projected tropical cyclone activity by 2050 generally declines in the South Indian Ocean, while changes in other ocean basins are more uncertain and sensitive to both tracking algorithm and imposed forcings. Coupled models with smaller biases suggest a slight increase in average TC 10 m wind speeds by 2050., Key Points Biases in tropical cyclone distribution, frequency, and intensity are generally reduced in models at 25 km resolutionNorthern Hemisphere basins show mixed responses to future forcing, while Southern Indian Ocean activity projected to declineFuture changes in 10 m wind speed in coupled models are mixed, and models with lower bias suggest small increases

Climate models suggest that future anthropogenic warming can slow hurricane motion, including near populated midlatitude regions., The locally accumulated damage by tropical cyclones (TCs) can intensify substantially when these cyclones move more slowly. While some observational evidence suggests that TC motion might have slowed significantly since the mid-20th century (1), the robustness of the observed trend and its relation to anthropogenic warming have not been firmly established (2–4). Using large-ensemble simulations that directly simulate TC activity, we show that future anthropogenic warming can lead to a robust slowing of TC motion, particularly in the midlatitudes. The slowdown there is related to a poleward shift of the midlatitude westerlies, which has been projected by various climate models. Although the model’s simulation of historical TC motion trends suggests that the attribution of the observed trends of TC motion to anthropogenic forcings remains uncertain, our findings suggest that 21st-century anthropogenic warming could decelerate TC motion near populated midlatitude regions in Asia and North America, potentially compounding future TC-related damages.

Previous projections of the frequency of tropical cyclone genesis due to global warming, even in terms of sign of the change, depends on the chosen model simulation. Here, we systematically examine projected changes in tropical cyclones using six global atmospheric models with medium-to-high horizontal resolutions included in the sixth phase of the Coupled Model Intercomparison Project/High-Resolution Model Intercomparison Project. Changes in the frequency of tropical cyclone genesis could be broken down into the contributions from (i) the tropical cyclone seed, a depression having a closed contour of sea level pressure with a warm core and (ii) the survival rate, the ratio of the frequency of tropical cyclone genesis to that of tropical cyclone seeds. The multi-model ensemble mean indicates that tropical cyclone genesis frequencies are significantly decreased during the period 1990–2049, which is attributable to changes in tropical cyclone seeds. Analysis of the individual models shows that although most models project a more or less decreasing trend in tropical cyclone genesis frequencies and seeds, the survival rate also contributes to the result in some models. The present study indicates the usefulness of decomposition into the frequency of the tropical cyclone seeds and the survival rate to understand the cause of uncertainty in projected frequencies of tropical cyclone genesis.

The observational impacts of satellite data assimilation on extended-range forecasts of sudden stratospheric warmings (SSWs) are investigated by conducting ensemble reforecast experiments. We use t...

Efficient injection of charge from metal electrodes into semiconductors is of paramount importance to obtain high performance optoelectronic devices. The quality of the interface between the electrode and the semiconductor must, therefore, be carefully controlled. The case of organic semiconductors presents specific problems: ambient deposition techniques, such as solution processing, restrict the choice of electrodes to those not prone to oxidation, limiting potential applications. Additionally, damage to the semiconductor in sputter coating or high temperature thermal evaporation poses an obstacle to the use of many device-relevant metals as top electrodes in vertical metal–semiconductor–metal structures, making it preferable to use them as bottom electrodes. Here, we propose a possible solution to these problems by implementing graphene-passivated nickel as an air stable bottom electrode in vertical devices comprising organic semiconductors. We use these passivated layers as hole-injecting bottom electrodes, and we show that efficient charge injection can be achieved into standard organic semiconducting polymers, owing to an oxide free nickel/graphene/polymer interface. Crucially, we fabricate our electrodes with low roughness, which, in turn, allows us to produce large area devices (of the order of millimeter squares) without electrical shorts occurring. Our results make these graphene-passivated ferromagnetic electrodes a promising approach for large area organic optoelectronic and spintronic devices. Organic semiconductors serve as a platform for (opto)electronic devices with tunable characteristics by molecular design, enabling versatile device integration, and processing strategies.1 However, ambient processing techniques such as solution processing can facilitate oxidation of metal contacts, resulting in an uncontrolled electronic interface, which is deleterious to performance in semiconductor devices.2,3 New techniques are, therefore, required to control the interface between organic semiconductors and oxidizing metals while maintaining the possibility of solution processing. Graphene has been shown to act as an atomically thin permeation barrier.4–6 Graphene grown via chemical vapor deposition (CVD) directly on the surface of strongly interacting7 catalytic metals, such as Ni, Co, or Fe, acts as a barrier layer to prevent oxidation.8–11 These oxide-free ferromagnetic interfaces have been shown to hold significant benefits within the field of spintronics,12,13 as they enable oxidative fabrication processes, such as solution processing9,10 or atomic layer deposition,14 to be used to fabricate devices with a wider range of relevant materials. One appealing possibility would be to develop graphene-passivated ferromagnets as electrodes9,10 for organic semiconductor spintronics,15–18 where the quality of the electronic interface between the ferromagnetic electrode and the organic semiconductor is of paramount importance.19,20 Another important advantage of an ambient-stable ferromagnetic layer is that it can be used as a bottom electrode in vertical metal-organic semiconductor–metal structures, allowing one to employ techniques such as sputtering to obtain high quality and thickness-controlled metal layers or multi-layers; note that sputtering cannot be used for top-electrodes as it would destroy21 the organic semiconductor. Previous reports using graphene passivated ferromagnets as electrodes for organic semiconductor devices have studied the spin injection properties10 as well as charge injection in lateral organic semiconductor field effect transistors.9 In this work, we investigate few-layer graphene-passivated nickel (Ni/FLG) as a bottom electrode for injection of holes into organic semiconducting polymers in a vertical device structure, demonstrating efficient injection into two standard semiconducting polymers deposited from solution and in air, directly on top of Ni/FLG. Compared to previous reports on graphene-passivated ferromagnetic electrodes, where lithographic techniques had to be used in order to produce micrometer-sized features,8–10,12,14 here, we were able to produce working devices with several orders of magnitude larger active area (4.5 mm2). Our results are, thus, encouraging for the further development of organic optoelectronic and spintronic devices processed from solution under ambient conditions. Nickel was initially sputtered on thermally oxidized silicon wafers, producing films with a thickness of 150 nm. FLG domains were grown on such sputtered Ni films in a custom low-pressure Chemical Vapor Deposition (CVD) reactor (base pressure ∼1 × 10−6 mbar). All substrates were cleaned by sonicating in acetone followed by isopropyl alcohol and blow-dried with a nitrogen gun before loading. Samples were heated to approximately 450 °C using a resistive heater (temperature measurements by a K-type thermocouple) with a rapid ramp rate of 100 °C/min and annealed at ∼1 mbar of H2 for 10 min. This reduces the native oxide prior to graphene growth. After annealing, the H2 flow was stopped and the chamber was evacuated back to approximately base pressure over a period of 5 min. For graphene growth, C2H2 gas was gradually introduced into the reactor via a mass flow controller by incrementally increasing the flow rate over 5 min to achieve a partial pressure of C2H2 of 2.5 × 10−4 mbar. Subsequently, the samples were held at 450 °C in 2.5 × 10−4 mbar of C2H2 for a further 25 min, before rapid cooling (initially ∼300 °C/min) while maintaining the C2H2 flow. All gases were stopped once room temperature had been reached. Upon graphene growth, a roughening of the Ni sputtered on thermally oxidized Si was observed, with an RMS = 67 nm [Fig. 1(a)]. The roughness was found to increase with increasing growth temperature. The roughening of Ni upon graphene growth is explained by grain growth in the sputtered Ni films, occurring at high temperatures during the CVD process: under these conditions, the internal forces in the film are larger than those between the film and the substrate, and diffusion of the film material is appreciable.

Reaction rates of toluene disproportionation (A) and cumene cracking (B) normalized by the number of Bronsted acid sites were analyzed on aluminosilicates. The activation entropy showed linear and compensatory relationship against the activation enthalpy. The slope of entropy-enthalpy plot was in the order of (B) > (A) > small alkane cracking, whereas the intercept on the horizontal axis was in the order of propane and isobutane cracking > linear C4–8 alkanes and iso-pentane cracking > (A) > (B). The former is consistent with the bulkiness of reactant, while the latter is consistent with intrinsic difficulty of formation of intermediate cations.

The predictability of a downward-propagating event of stratospheric planetary waves observed in early March 2007 is examined by conducting ensemble forecasts using an AGCM. It is determined that the predictable period of this event is about 7 days. Regression analysis using all members of an ensemble forecast also reveals that the downward propagation is significantly related to an amplifying quasi-stationary planetary-scale anomaly with barotropic structure in polar regions of the upper stratosphere. Moreover, the anomaly is 90° out of phase with the ensemble-mean field. Hence, the upper-stratospheric anomaly determines the subsequent vertical-propagating direction of incoming planetary waves from the troposphere by changing their vertical phase tilt, which depends on its polarity. Furthermore, the regressed anomaly is found to have similar horizontal structure to the pattern of greatest spread among members of the predicted upper-stratospheric height field, and the spread growth rate reaches a maximum prior to the occurrence of the downward propagation. Hence, the authors propose a working hypothesis that the regressed anomaly emerges as a result of the barotropic instability inherent to the upper-stratospheric circulation. In fact, the stability analysis for basic states constituting the ensemble-mean forecasted upper-stratospheric streamfunction field using a nondivergent barotropic vorticity equation on a sphere supports this hypothesis. Thus, the barotropic instability inherent to the distorted polar vortex in the upper stratosphere forced by incoming planetary waves from the troposphere determines whether the planetary waves are eventually absorbed or emitted downward in the stratosphere.

Projected future changes in global tropical cyclone (TC) activity are assessed using 5,000 year scale ensemble simulations for both current and 4 K surface warming climates with a 60 km global atmospheric model. The global number of TCs decreases by 33% in the future projection. Although geographical TC occurrences decrease generally, they increase in the central and eastern parts of the extra tropical North Pacific. Meanwhile, very intense (category 4 and 5) TC occurrences increase over a broader area including the south of Japan and south of Madagascar. The global number of category 4 and 5 TCs significantly decreases, contrary to the increase seen in several previous studies. Lifetime maximum surface wind speeds and precipitation rate are amplified globally. Regional TC activity changes have large uncertainty corresponding to sea surface temperature warming patterns. TC-resolving large-ensemble simulations provide useful information, especially for policy making related to future climate change.

An unprecedentedly large ensemble of climate simulations with a 60-km atmospheric general circulation model and dynamical downscaling with a 20-km regional climate model has been performed to obtain probabilistic future projections of low-frequency local-scale events. The climate of the latter half of the twentieth century, the climate 4 K warmer than the preindustrial climate, and the climate of the latter half of the twentieth century without historical trends associated with the anthropogenic effect are each simulated for more than 5,000 years. From large ensemble simulations, probabilistic future changes in extreme events are available directly without using any statistical models. The atmospheric models are highly skillful in representing localized extreme events, such as heavy precipitation and tropical cyclones. Moreover, mean climate changes in the models are consistent with those in phase 5 of the Coupled Model Intercomparison Project (CMIP5) ensembles. Therefore, the results enable the assessment of probabilistic change in localized severe events that have large uncertainty from internal variability. The simulation outputs are open to the public as a database called “Database for Policy Decision Making for Future Climate Change” (d4PDF), which is intended to be utilized for impact assessment studies and adaptation planning for global warming.