A record of the secular variation of the geomagnetic field for the last 11000 years has been obtained from the remanent magnetization of seven wide-diameter (20 cm) cores of marine and lacustrine sediment from central to south-west Japan. Magnetization directions of five cores, possessing high-amplitude variations, exhibit good correlation. Two cores show low- amplitude variations, but they can be correlated well with other records after deconvolution to remove filtering effects of the post-depositional magnetization process. A composite secular variation curve was constructed by stacking the field direction records. Time constraints were obtained from radiocarbon ages of shell and wood fractions or tephrochronology. The secular variation curve agrees well with the archeomagnetic record after 1400 yrBP, with a slight difference in the time range 1400-2000 yrBP. The secular variation for the last 11000 years shows an elongated distribution of VGP's. The azimuth of the elongation, about 40°E, is consistent with that of VGP's from Japanese volcanic and sedimentary rocks during Brunhes epoch. The angular standard deviation is 14.5° (upper limit = 15.4°, lower limit = 13.7°). This estimate is slightly larger than that observed globally during Brunhes epoch and the position of the average VGP deviates 8.5° from the geographic north pole. These VGP analyses suggest a stationary nondipole source. The secular variation records from five northern hemisphere sites between 135°E and 95°W in longitude possess a single prominent feature: an extreme easterly swing in declination. A plot of age versus longitude of the swing at each site shows a clear westward drift, at a rate of about 0.13° /yr. The field vector around the swing represents clockwise looping at all the sites. This suggests that the swing is caused by a large non-dipole source which drifts at least from 135°E to 95°W in longitude.

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The strength analysis of stiffened shell structure in ship hull involve to clarify strength characteristics of shell itself and the effect of shapes of the objects in addition to the effect of various reinforced ways. The first report presented a method of analyzing stiffened shells with simply supported edges and of rectangular form by means of finite strip method. And it is found that fairly high accurate solutions were obtained by this method in spite of lightening the volume of calculations.
Boundary conditions for stiffened panels of actual ship-hull-structure are considered as free or elastic supported besides simply supported depending on adjacent structural conditions. Moreover, the boundary shapes of curved hull panels in ship bow or stern structure are non-rectangular occasionally and the directions of fitted stiffeners are oblique to shell edges.
To increase the applicability for strength analysis of ship construction, this paper presents extensions of the analytical method described in the first report by treating following items;
a) various boundary conditions for applying practical cases b) curved shell panels of non-rectangular shapes ) with obliquely fitted stiffeners.
For the item a), it is settled by using a buckling modes of beam as displacement functions and for the item b) and c), the method of linear transformations of variables has been applied.
Some examples are shown for the cases of analyzing bending of shallow shells without and with stiffeners which are of various shapes and various edge conditions. The results prove that proposed method is one of effective means for analyzing the curved parts of ship construction.

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This paper is concerned with the limit analysis of shells of revolution made of a rigid-perfectly-plastic material that obeys Tresca's yield condition. The four-dimensional yield hypersurface for shells of revolution was once presented by E.T. Onat and W. Prager. Using this yield surface, a numerical solution for simply supported conical shells was obtained by R.H. Lance and E.T. Onat. Fundamentally based on their method and considering more precisely the yield hypersurface, a numerical method is presented that can be applied to general shells of revolution. As numerical examples, the solutions for truncated conical shells, and pressure vessels with rigid circular plates are presented. These solutions verify that this method is correct.

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We investigated the effects of temperature on the survival and growth of veliger larvae of the cone snails Conus fulmen and Conus pulicarius using an individual larval rearing system. Newly hatched veligers of C. fulmen were cultured at 21, 24, 27, and 30 °C, whereas those of C. pulicarius were cultured at 21, 24, 27, 30, and 33 °C. Larval survival and shell growth were monitored daily, and shell growth was analyzed using logistic growth equations. No larvae of either species metamorphosed during the experiments. Survival of C. fulmen remained high (91.7–100 %) at all temperatures and was not significantly affected by temperature. In contrast, survival time of C. pulicarius was significantly affected by temperature, and all larvae died by day 38 at 21 °. growth of both species was well described by logistic growth equations. The lower temperature limits for larval growth were estimated to be 18.6 °C for C. fulmen and 20.5 °C for C. pulicarius. These findings indicate greater low-temperature tolerance in veliger larvae of C. fulmen than in those of C. pulicarius and reveal species-specific thermal responses in larval performance that correspond to the geographic distributions of these species.

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To complete the decommissioning of the Fukushima Daiichi Nuclear Power Station (referred to as 1F), it is necessary to maintain damaged components and equipment in a safe state for medium and long term. The subcommittee of structural integrity of components was established in 2019 as a subcommittee of Review Committee on Decommissioning of the 1F of the Atomic Energy Society of Japan. The purpose of this subcommittee is to discuss the structural integrity evaluation standards for components and equipment that have partially lost their strength due to a severe accident, and to propose a concept on appropriate standards.

Target components and equipment are the reactor primary containment vessel (referred to as PCV) and its internal structure, e.g.: the pedestal of unit 1 to 3. Therefore, it is necessary to consider not only the required functions specific to the damaged components and equipment, which should be different from an operating plant, and also the magnitude of uncertainty in evaluating structural integrity. The subcommittee has been discussing concepts of structural integrity evaluation considering large uncertainties. This paper describes the concept on structural integrity evaluation for 1F.

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A bizarre gastropod species, Pluviostilla palauensis from a shallow-water, submarine cave (gloomy to totally dark inside) in Palau is described as a new genus and species based on the empty shells. The species is small in size and has unique shell features such as an overall inverse raindrop-shape, architectonicoidean-like planispiral early teleoconch whorls, abapically projected tube-like aperture and hollowed umbilicus completely closed by the whorls. Shell wall microstructure and protoconch morphology suggest a possible affinity to neritopsines, but it is very tentative and the systematic position of this species is still unknown. A sedentary mode of life, as in architectonicoideans, is inferred for the species.

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We have successfully fabricated hollow core-shell type Si/C nanocomposites using a simple process. Si powder was grinded to form Si nanoparticles, mixed with sucrose as a carbon source and ammonium chloride as an expansion agent, and finally annealed in Ar atmosphere. During the annealing, carbon hollow spheres encapsulating Si nanoparticles were spontaneously fabricated through dehydrogenation reaction of the sucrose to form carbon balloons and the balloon expansion by ammonium gas generated during ammonium chloride decomposition. Volume of the empty spaces in the core-shell structure can be controlled by the rising rate in the annealing temperature. This method is suitable for industrial production of hollow Si/C nanocomposites because of its simplicity. [DOI: 10.1380/ejssnt.2017.69]

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Pen shells, Atrina spp., were important marine product in the northern Ariake Sea until recent years, but most of the pen shell populations have collapsed over the past two decades. In the present study, recruitment, growth, and mortality were compared among three pen shell populations, at Site A (intertidal zone), Site B (upper subtidal zone, 3 m in depth), and Site C (subtidal zone, 7 m in depth) in the northeast fishery zone of the Ariake Sea from 2000 to 2006. The maximum mortality rate (maximum proportion of dead shells on each sampling date) was low at Site A (12.8%) and Site B (7.8%). On the other hand, at Site C, most pen shells have died, with undamaged shells mainly from spring to summer and, in most years, a maximum mortality rate of over 80% present. At Site , density decreased greatly during the study period, but it was much higher than at Site A or B. Growth was slower and the soft body weight was lower at Site C than at Sites A and B, but the seasonal pattern of relative gonad weight was not very different among the three sites. These results suggested that there has been a deterioration of habitat conditions at Site C and that excessive reproductive investment under bad conditions might have led to the massive die-offs there. Although the direct cause of these die-offs is unclear, it is certain that degradation of sea-bottom conditions as a result of, e.g., hypoxia, increase in sulfide concentration, and decrease in grain size of the sediment, affects the survival of pen shells directly.

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丹沢山塊に分布する煤ヶ谷亜料群から産出する化石については, すでに二・三の報告がある。筆者は, 本亜層群から産出する化石について検討した結果, あらたに3新種をみとめたので記載した。なお, 本亜層群の化石は, 暖疏系・岩礁性で特徴ずけられている。また, 本亜層群の基底からLepidocyclina nipponica HANZAWAが発見された。これらの資料をもとにして, 本亜層群の地質時代, および対比についても言及した。

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The casting characteristics of various Al-Li alloys were investigated. Li losses in Al-3%Si-1%Mg-0.15%Zr containing 1, 2 and 3%Li are about 0.1, 0.2 and 0.4%, respectively when the alloys were melted and held for 3ks at 973K in air. The hydrogen content of molten Al-Li alloys is lowered from 1.00ml/100g to 0.75ml/100g when the Ar degassing time is extended from 300s to 1.8ks at 973-983K. The phenol resin-bonded sand mold coated with MgO, heated and then cooled in vacuum is suitable for casting of Al-Li alloys. The fluidity of Al-2%Cu-1%Mg-0.15%Zr and Al-3% Si-1%Mg-0.15%Zr alloys is not almost changed by the addition of Li up to 3%. The fluid length of these Al-Li alloys is inferior around 85% to that of AC4C (Al-7%Si-0.3%Mg).

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　軽い領域のみならず中重核領域においてもαクラスター構造が現れる可能性が指摘されており、最近^48^Tiが注目を集めている。本研究では、Antisymmetrized quasi cluster model (AQCM)を用い、^48^Tiがシェル構造を持つ場合とクラスター構造を持つ場合の波動関数を同一の枠組みで用意した。得られた密度分布をグラウバー模型に適用し、陽子弾性散乱実験と比較することで、^48^Tiがシェルとクラスターのどちらの描像に近いのかを明らかにした。特に、核表面において、シェル構造がクラスター構造に移り変わる可能性を議論する。

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港の内側と外側においてクロタマキビLittorina sitkana（Philippi，1845）の形態・生態的差異を比較し，それぞれの環境に対して適応的か否かを検討した。港の内外は幅約1 mのコンクリート壁で分断されている。港の内側の基質は人工的にセメントで固められており，色は黒い玉石とコンクリートの灰白色がモザイク状に分布する。捕食者と考えられるイソガニHemigrapsus sanguineusの存在は調査期間中に確認された。波圧は，外側と比較して弱い。一方，港の外側の基質は天然の岩礁で，表面は灰白色のイワフジツボChthamalus challengeriで覆われており，調査期間中にイソガニは確認されず，波圧は強い。港の内側に生息する本種の殻色は全体的に暗褐色で，貝殻は堅く，貝殻表面の構造は滑らかで，足のサイズは比較的小さいといった形質を持つ個体が非常に多い。一方，港の外側では，貝殻の殻頂部は灰褐色であるが成長の途中で灰白色へ変化し，貝殻は壊れやすく，貝殻表面はリブレットで覆われ，足のサイズは比較的大きいといった形質を持つ個体が非常に多い。イソガニを用いた捕食実験の結果，捕食者と同所的ではない外側の個体のみ捕食された。水流耐性実験では，波圧が弱い内側の個体の耐性が低かった。港の内外で見られる形態・生態的差異は，それぞれの環境に対して適応的なものであると考えられた。

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Climate policies at a national level and private sector initiatives are becoming important. Climate actions are of paramount importance as a policy priority for the EU and the Democrats/Democratic-leaning independents in the United States. In the EU and the United States, climate policies, and trade and financial policies are being linked. European Commission President von der Leyen considers introducing a carbon border adjustment mechanism, and in the United States both Democrats and Republicans also consider imposing a border carbon adjustment for the presidential election. In the EU, a unified classification system （ʻtaxonomyʼ） on what can be considered an environmentally sustainable economic activity is discussed in order to facilitate sustainable investment. In the United States, on the other hand, there is a discussion on whether ESG finance hinders energy infrastructure investment. Behind long-term strategies of global energy companies towards a low carbon economy lie the recommendations of the Task Force on Climate-related Financial Disclosure and institutional investors groupsʼ move over shareholder resolutions. Against this background, some upstream energy and utility companies have sold coal assets, strengthened natural gas assets or switched to renewable energy and energy efficiency businesses, while others sold natural gas assets from a longer-term perspective. In addition, several upstream energy companies, especially the US companies, recently invested in technologies such as CCUS.

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X-ray absorption fine structure (XAFS) analysis was applied to elucidate Cr(VI/III) speciation during reaction with standard humic acid materials extracted from Japanese soils. The degree of reduction of Cr(VI) by humic acids differed for different degrees of humification. Adsorption of Cr(III) to humic substances was higher for higher carboxylic humic substance contents. After reduction experiments of Cr(VI) by humic acids, Cr binding with humic acids has a trivalent state. Nevertheless, a substantial amount of Cr(VI) remains in solution. The X-ray absorption near-edge structure (XANES) spectra of the Cr(VI) experimental system were almost identical to those of Cr(III) adsorbed onto humic acids in a low-pH condition. However, during adsorption of Cr(III) by humic acids, Cr was partly precipitated as Cr(OH)₃·nH₂O. Its concentration was higher for higher pH. XANES spectra of Cr(VI/III) reacted with different humic acids showed no systematic differences, indicating that the binding form of Cr to humic substances is common, irrespective of differences in functional group concentrations. Linear combination fitting using XANES spectra of reference compounds to HA-Cr samples suggests that 50% hydrated Cr(III) was adsorbed onto HA and that the remainder of Cr(III) was bound to carboxylic acid of HA. The local structure of Cr binding to humic acids was characterized using extended X-ray absorption fine structure (EXAFS) spectroscopy. The EXAFS features of Cr binding to humic acids were similar to those of Cr³⁺ aquo ions having simple octahedral symmetry of the oxygen coordination sphere. They show no clear presence of carboxylic group of humic acids around the Cr site. Scattering from the C atom might not be visible because the backscatter amplitude of a C atom becomes weak steeply with increasing wavenumber (k) and because it is smaller than those of the O atom and the Cr atom. Considering the linear combination fitting results of XANES spectra, the structural mode of Cr binding with HA is R-COO-Cr-(OH₂)₅.

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Field surveys of the bacterium Francisella halioticida infection among intermediate-cultured juvenile scallops Mizuhopecten yessoensis in southern Hokkaido revealed that the mortality of juvenile scallops was positively associated with the prevalence of F. halioticida, and that both mortality and prevalence increased in September and January. ​In the intermediate culture experiments, juvenile scallops reared under high density during September and October resulted in high prevalence of F. halioticida and scallop mortality after October, while rearing density from October to March was not associated with infection and mortality, indicating that the high rearing density between September and October determined the infection of F. halioticida and scallop mortality in the following period. ​Furthermore, shell deformity rates, as a proposed index for poor physiological condition of juvenile scallops, were high in the experimental groups with higher density from September to October. ​The high rearing density in this term may have caused a decline in physiological status and, reduced resistance to francisellosis in juvenile scallops, although there is still a possibility that shell deformity was caused by francisellosis.

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The syslog messages of the iplog-2.2.3 packet capture in the DNS servers in Ku mamoto University were statistically investigated when receiving abnormal TCP packets from PC terminals infected with internet worms like W32/Welchia and/or W32/Sasser.D worms. The interesting results are obtained: (1) Initially, the W32/Welchia worm-infected PC terminals for learners (920 PCs) considerably accelerates the total W32/Welchia infection. (2) We can suppress quickly the W32/Sasser.D infection in our university when filtering the access between total and the PC terminal's LAN segments. Therefore, infection of internet worm in the PC terminals for learners should be taken into consideration to suppress quickly the infection.

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