We investigated an effect of carbon fiber on shape memory property of carbon fiber / shape memory polymer (epoxy resin) composites by using dynamic mechanical analysis (DMA), shape memory test, and mechanical constitutive model. As a result of DMA, the storage modulus (E') of the composite material (CF/EP) was improved by CF component, as compared with that of the pure epoxy resin (pure EP). Especially, E' at rubbery region was remarkably increased with two decades. From the results of shape memory test, CF/EP showed good shape recovery behavior as well as pure EP. Contrary, the shape fixity ratio of CF/EP was lower than that of pure EP. This is because that the difference in E' below/above the glass transition temperature (T_g ) of CF/EP became smaller (less than one decade) than pure

( decades). In addition, the shape recovery of CF/EP started at lower temperature than T_g, although the recovery of pure EP showed around T_g. In order to examine the shape recovery behavior of CF/EP, we compared the viscoelastic properties of three samples, pure EP, CF layer and the composite. As a result, the CF layer had higher E' than CF/EP, and no significant change in E' occurred around T_g. From the results, we speculated that the CF layer acted as a shape recovery component for the composite material. Furthermore, we proposed a mechanical constitutive model, in which the CF layer was assumed as the recover component, to qualitatively explain the shape recovery behavior of CF/EP composite. The simulated result by the constitutive model reproduced the trend of anomalous shape recovery behavior below T_g of CF/EP.

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In order to improve the breakdown properties of low density polyethylene (LDPE), the electrical properties of blend polymers of LDPE and random copolymer of ethylene and propylene (EP) have been investigated at 30°C, 60°C and 90°C. The specimen with a higher. EP content had a higher impulse breakdown strength at 90°C than the specimen with a lower EP content, but there was no obvious difference at 30°C and 60°C However, in the case of DC breakdown, any improvement was not recognized for blend polymers throughout the temperature range from 30°C to 90°C, The morphology of blends was studied by a polarizing microscope and X-ray diffraction, The influences of morphology on breakdown properties were discussed. The morphological change by introduction of EP into LDPE was demonstrated by the decrease in the size of a spherulite, the existence of EP in the inter-spherulitic boundary region and the enhancement of orientation. The improvement of impulse breakdown strength at 90°C was explained on the basis of morphological change.

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オオバスノキにおける四集粒花粉の個体発生過程を,特に花粉外壁の沈着様式に着目して,光学顕微鏡と透過型電子顕微鏡により研究した.細胞表面を覆った原繊維状の層として現われる一次外壁マトリックスの沈着は,厚いカロース壁内で小胞子母細胞が細胞分裂している間に始まった.スポロポレニン前駆物質である濃いリポイド様顆粒の沈着が,一次外壁マトリックスの中に観察された.これらの顆粒が見えなくなった後に放射方向に向いた一次小柱が一次外壁マトリックスの中に現れ,カロース分解後にはこの一次外壁は外表層,柱状層,底部層を生じる.将来の花粉開口部の位置は,一次外壁マトリックスの厚い部分と(あるいは)薄い部分とに観察された.これら将来開口部になる領域では一次小柱,一次外表層そして底部層は形成されなかった.オオバスノキの成熟花粉における四花粉粒間の接合機構としては,1)細胞分裂を行っている小胞子母細胞上に一次外壁マトリックスが早期に沈着すること,厚いカロース壁に包まれた減数分裂四分子内の隣接する小胞子間では2)ごく薄いカロース沈着しかおこらないこと,3)一次外壁マトリックスが共有されること,4)細胞チャンネルが形成されること,が考えられる.

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Pulmonary and extrapulmonary complications after coronavirus disease 2019 (COVID-19) have been major public health concerns during the COVID-19 pandemic. Although post-COVID-19 pulmonary manifestations cover a wide spectrum, eosinophilic pneumonia (EP) has rarely been reported. To date, only four cases of EP potentially triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been reported, all of which required systemic corticosteroid therapy. We herein report the first case of post-COVID-19 EP resolution without systemic corticosteroid therapy. We also review the literature regarding EP associated with SARS-CoV-2 infection and vaccination.

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The first inventory of the spider fauna of the Lut Desert, known as one of the hottest deserts in the world, is provided. Spiders collected during the Iranian Biological Expedition in November 2016 are reported. We identified 15 species belonging to 12 families, including the new species, Oecobius fahimii sp. n. (female, Oecobiidae), which is described and illustrated here. In addition, three species – Devade tenella (Tyshchenko 1965) (Dictynidae), Gnaphosa ukrainica Ovtsharenko, Platnick et Song 1992 and Haplodrassus caspius Ponomarev et Belosludtsev 2008 (both Gnaphosidae) – are reported from Iran for the first time.

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The importance of preventing infectious disease for public health continues to increase, and effective disinfectants are needed to inactive pathogenic microorganisms. Chlorine dioxide (ClO₂) is known as one of the most efficient disinfectants. We studied the inhibitory effect of a novel disinfectant, MA-T, for three species of bacteria (Escherichia coli, Staphylococcus aureus, and Aggregatibacter actinomycetemcomitans). We found that NADH:O₂ oxidoreductase activity (NADH oxidase activity) was markedly decreased in all three species, corresponding to the decrease in colony-forming units following treatment with MA-T. In E. coli, NADH:ubiquinone-1(Q₁) oxidoreductase (NADH-Q₁ dehydrogenase; NDH) activity was decreased following MA-T exposure, indicating that both the NDH-1 and NDH-2 enzymes were targets of this disinfectant. The activity of ubiquinol-1 (Q₁H₂): O₂ oxidoreductase (Q₁H₂ oxidase) also was decreased, indicating that cytochromes bo3 and bd were damaged by MA-T. In S. aureus, NADH-ferricyanide dehydrogenase activity and Q₁H₂ oxidase activity were strongly decreased, suggesting that NDH-2, cytochrome bd, and cytochrome aa3 were targets of MA-T in this species. In A. actinomycetemcomitans, only Q₁H₂ oxidase activity was decreased, indicating that in this species, only cytochrome bd was impaired by MA-T treatment. NADH oxidase activity in membrane vesicles prepared from untreated E. coli was not markedly affected by treatment with MA-T, suggesting that MA-T may attack components of the respiratory chain only in live bacteria (i.e., those possessing a membrane potential), because the membrane vesicles cannot produce the membrane potential.

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The garbage can model created by Cohen, March, and Olsen (1972) explains organizational decision making under ambiguity. In the initial study outlining the model, a computer simulation was used for analysis. However, despite the appendix of Cohen et al. (1972) providing the Fortran source code for the simulation, subsequent studies rarely made any reference to the simulation model. In this study, we examine the simulation model of Cohen et al. by rebuilding the aforementioned source code. The results of our study clearly indicate the following three points. 1) the program created by Cohen et al. failed to detect the three decision-making styles (decision by resolution, decision by oversight, and decision by flight); 2) decision making sometimes occurred not only when choice opportunities had no problems but also when a choice opportunity had no decision maker; and 3) even when there were no problems attached to choice opportunities, the initial setting was programmed as though there were, perhaps to avoid the decision making seen in 2).

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