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Tide gauge data indicated that ocean waves were generated by the eruption of the Hunga Tonga-Hunga Ha'apai volcano on January 15, 2022. These high-amplitude waves reached the Japanese coast earlier than expected for free ocean waves. These fluctuations in sea level were reasonably reproduced by an ocean model, with realistic bottom topography forced by sea-level pressure perturbations well reproduced by atmospheric general circulation models. While early arrival times are associated with atmospheric Lamb waves, the amplitude of the sea level changes cannot be fully explained by the resonance mechanism associated with sea-level pressure fluctuations of Lamb and Pekeris waves alone. Rather, resonance due to atmospheric waves in conjunction with the amplification effects caused by a steep continental slope is required in order to reproduce sea level fluctuations along the Japanese coast. In particular, the deep Northwest Pacific Basin to the east of Japan is important for strengthening the amplitude of the meteorological tsunami. • Sea level fluctuations due to the 2022 volcanic eruption in Tonga was reproduced. • Meteorological tsunamis were generated by Lamb and Pekeris waves. • Meteorological tsunamis by Pekeris waves are amplified due to Proudman resonance. • Meteorological tsunamis are amplified by entering the sharp continental slope. [ABSTRACT FROM AUTHOR]

Abstract: We evaluated the impact of subgrid-scale ice thickness distribution on the heat flux on and through sea ice in a numerical model. An ice-ocean coupled model with a subgrid-scale ice thickness distribution scheme, COCO4.5, is forced by an atmospheric climatology to simulate the present state of the sea ice and ocean. The modeled climatology reproduces the ice cover reasonably well with a realistic ice thickness distribution. The heat flux on and through the sea ice is established using the grid-averaged sea-ice and snow-on-ice thickness from the results of the simulation. When the grid-averaged thickness is calculated as a weighted arithmetic mean, the conductive heat flux through the ice and snow is underestimated compared with that actually driving the model. This underestimation becomes smaller in magnitude when either a weighted harmonic mean or a weighted arithmetic mean with a modification based on the ratio of these two types of means is used. Rearrangement of the ice categories shows that the flux bias decreases with an increase in the number of categories. We also perform a sensitivity experiment in which the model is forced by the biased heat flux identified using the arithmetic mean of the ice thickness. A significant decrease in ice volume is found, notably in the Arctic Ocean. These results suggest that sea-ice models without an ice thickness distribution scheme underestimate the conductive heat flux through ice, and thereby the resultant sea-ice thickness, because the ice thickness from these models typically corresponds to the weighted arithmetic mean thickness. [Copyright &y& Elsevier]

Abstract: Calcium/calmodulin-stimulated protein kinase II (CaMKII) is an important mediator of synaptic function that is regulated by multi-site phosphorylation and targeting through interactions with proteins. A new phosphorylation site at Thr253 has been identified in vivo, that does not alter CaMKII activity, but does alter CaMKII function through interactions with binding proteins. To identify these proteins, as well as to examine the specific effects following Thr253 or Thr286 phosphorylation on these interactions, we developed an in vitro overlay binding assay. We demonstrated that the interaction between CaMKII and its binding proteins was altered by the phosphorylation state of both the CaMKII and the partner, and identified a CaMKII-specific sequence that was responsible for the interaction between CaMKII and two interacting proteins. By comparing CaMKII binding profiles in tissue and cell extracts, we demonstrated that the CaMKII binding profiles varied with cell type, and also showed that overexpression of a CaMKII Thr253 phospho-mimic mutant in human neuroblastoma and breast cancer cells dramatically altered the morphology and growth rates when compared to overexpression of non-phosphorylated CaMKII. This data highlights the importance of the microenvironment in regulating CaMKII function, and describes a potentially new mechanism by which the functions of CaMKII can be regulated. [Copyright &y& Elsevier]

Abstract: We previously reported the partial identification by random sequencing of mRNA species that are associated with the postsynaptic density (PSD) fraction prepared from the rat forebrain [Tian et al., 1999. Mol. Brain Res. 72, 147–157]. We report here further characterization by gene chip analysis of the PSD fraction-associated mRNAs, which were prepared in the presence of RNase inhibitor. We found that mRNAs encoding various postsynaptic proteins, such as channels, receptors for neurotransmitters and neuromodulators, proteins involved in signaling, scaffold and adaptor proteins and cytoskeletal proteins, were highly concentrated in the PSD fraction, whereas those encoding housekeeping proteins, such as enzymes in the glycolytic pathway, were not. We extracted ∼1900 mRNA species that were highly concentrated in the PSD fraction. mRNAs related to certain neuronal diseases were also enriched in the PSD fraction. We also constructed a cDNA library using the PSD fraction-associated mRNAs as templates, and identified 1152 randomly selected clones by sequencing. Our data suggested that the PSD fraction-associated mRNAs are a very useful resource, in which a number of as yet uncharacterized mRNAs are concentrated. Identification and functional characterization of them are essential for complete understanding of synaptic function. [Copyright &y& Elsevier]

Abstract: Detection efficiency of fission tracks in non-annealed and annealed Durango apatite crystals related to mica external detectors for fission track dating was estimated experimentally using the spike irradiation technique [Suzuki, 2002a. Abstracts of 21st International Conference on Nuclear Tracks in Solids, p. 22]. The relation of the fission track density between apatite samples and mica external detectors is an important parameter for the determination of fission track ages using an absolute approach especially for crystalline minerals. Spike irradiation of uranium-235-induced fission fragments was carried out using a high uranium content glass, GE1497, fixed firmly on the sample surface. Experimental works were carried out for sections parallel and perpendicular to the crystallographic -axis of apatite. The detection efficiency of fission tracks in non-annealed apatite related to the mica external detectors was estimated to be 0.90 for the prism face and 0.99 for the basal face. The fission track age of Durango apatite averaged for the prism and basal faces was estimated to be 30.6 Ma, which is concordant with reference values reported previously, using the detection efficiency data with a value of the CN5 monitor glass and a U-238 spontaneous decay constant value of . The results also indicate that the age calibration method can be used effectively for the absolute evaluation of fission track ages of apatite. [Copyright &y& Elsevier]

Ketene N,O-acetals were prepared stereoselectively and submitted to a Lewis acid-mediated 1,3-rearrangement to afford C-alkylated products. The reactions proceeded in a stereoselective manner to construct a chiral quaternary carbon in high selectivity. The stereochemistry of the quaternary center was found to be opposite to that obtained by an anionic direct dienolate alkylation. [Copyright &y& Elsevier]

Accumulating evidence suggests that special lipid microdomains in the lipid membrane play various roles in cellular functions. Neurons also have such microdomains, non-caveolar lipid rafts. However, the rafts at the synaptic sites had not been reported until 2001, when a raft-like fraction was purified from synaptic plasma membrane of the rat forebrain (Mol. Brain Res. 89 (2001) 20). This article reviews recent findings on lipid rafts, especially those in the brain, and discusses the possible interaction between the postsynaptic raft and the postsynaptic density, both of which are essential for the structure and function of the postsynaptic side of the synapse. [Copyright &y& Elsevier]

Synthetically useful β,γ-unsaturated carbonyl compounds having a quaternary carbon at the α-position were prepared with high stereoselectivity by the reaction of a dienolate anion derived from α,β-unsaturated imide having a chiral auxiliary and electrophiles (ethyl acetate and allyl iodide as the C2 and C3 unit, respectively). This method was applied to a short asymmetric synthesis of (+)-ethosuximide. [Copyright &y& Elsevier]

Highlights • A new surface dataset for driving ocean-sea ice models (JRA55-do) is produced. • This dataset aims to replace the dataset currently used in the CORE/OMIP framework. • The merits of JRA55-do are the high horizontal resolution (≈ 55 km) and temporal interval (3 h). • JRA55-do corrects JRA-55 using satellite and other atmospheric reanalysis products. • Assessment shows that JRA55-do can suitably replace the current CORE/OMIP dataset. Abstract We present a new surface-atmospheric dataset for driving ocean–sea-ice models based on Japanese 55-year atmospheric reanalysis (JRA-55), referred to here as JRA55-do. The JRA55-do dataset aims to replace the CORE interannual forcing version 2 (hereafter called the CORE dataset), which is currently used in the framework of the Coordinated Ocean-ice Reference Experiments (COREs) and the Ocean Model Intercomparison Project (OMIP). A major improvement in JRA55-do is the refined horizontal grid spacing (∼ 55 km) and temporal interval (3 hr). The data production method for JRA55-do essentially follows that of the CORE dataset, whereby the surface fields from an atmospheric reanalysis are adjusted relative to reference datasets. To improve the adjustment method, we use high-quality products derived from satellites and from several other atmospheric reanalysis projects, as well as feedback on the CORE dataset from the ocean modelling community. Notably, the surface air temperature and specific humidity are adjusted using multi-reanalysis ensemble means. In JRA55-do, the downwelling radiative fluxes and precipitation, which are affected by an ambiguous cloud parameterisation employed in the atmospheric model used for the reanalysis, are based on the reanalysis products. This approach represents a notable change from the CORE dataset, which imported independent observational products. Consequently, the JRA55-do dataset is more self-contained than the CORE dataset, and thus can be continually updated in near real-time. The JRA55-do dataset extends from 1958 to the present, with updates expected at least annually. This paper details the adjustments to the original JRA-55 fields, the scientific rationale for these adjustments, and the evaluation of JRA55-do. The adjustments successfully corrected the biases in the original JRA-55 fields. The globally averaged features are similar between the JRA55-do and CORE datasets, implying that JRA55-do can suitably replace the CORE dataset for use in driving global ocean–sea-ice models. [ABSTRACT FROM AUTHOR]