504 research outputs found

    Do Uric Acid Deposits in Zooxanthellae Function as Eye-Spots?

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    The symbiosis between zooxanthellae (dinoflagellate genus Symbiodinium) and corals is a fundamental basis of tropical marine ecosystems. However the physiological interactions of the hosts and symbionts are poorly understood. Recently, intracellular crystalline deposits in Symbiodinium were revealed to be uric acid functioning for nutrient storage. This is the first exploration of these enigmatic crystalline materials that had previously been misidentified as oxalic acid, providing new insights into the nutritional strategies of Symbiodinium in oligotrophic tropical waters. However, we believe these deposits also function as eye-spots on the basis of light and electron microscopic observations of motile cells of cultured Symbiodinium. The cells possessed crystalline deposit clusters in rows with each row 100–150 nm thick corresponding to 1/4 the wavelength of light and making them suitable for maximum wave interference and reflection of light. Crystalline clusters in cells observed with a light microscope strongly refracted and polarized light, and reflected or absorbed short wavelength light. The facts that purines, including uric acid, have been identified as the main constituents of light reflectors in many organisms, and that the photoreceptor protein, opsin, was detected in our Symbiodinium strain, support the idea that uric acid deposits in Symbiodinium motile cells may function as a component of an eye-spot

    STUDIES ON THE DISTRIBUTION OF THE EPILACHNID BEETLES IN GUMMA PREFECTURE, JAPAN

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    The authors have studied the distribution of the Epilachnid beetles in Gumma-pref. since 1956, and the following results are obtained as summary. 1. Epilachna sparsa is recognized to be distributed to some extent at the southern plain places of Gumma-pref. such as Tomioka, Takasaki, Maebashi, Ogomachi, Isezaki, Ota, Tatebayashi, Kasakakemura and their neighbors, where the altitude is less than 150m (Fig. 1). At these places sparsa lives intermingled with 28-maculata. 2. At the higher places with 150300m altitude such as Shibukawa, Onogami, Yoshioka, Misato, Akagimura, Hokkitsumura, Komochimura and their neighbors (Fig. 1), sparsa tends to live being segregated from 28-maculata in the same farm. 3. The species feeds usually on the Solanaceous plants, among which ground cherry is the best host plant. The number of the generation is generally two but rarely three. 4. E. 28-maculata is the species having the widest distribution in Gumma-pref. (Fig. 1) and we can see it everywhere, potatoes, egg-plants and tomatoes are planted, with exception of one place near Ozegahara. The highest limit of the distribution may be 1300m. 5. The host plant of 28-maculata is the Solanaceous plants with the exception of ground cherry and redpepper, on which the larvae cannot grow. The number of the generation is one but very rarely may be two. 6. Ea pustulosa inhabits mainly at the northern places of Gumma-pref. such as Anabara, Hikagenango, Neri, Akagizawabashi, Tokusa, Kashozan, Akakura, Doai, Fujiwara, Uenohara, Sugenuma, H6shi and Omineyama. All these places are located along the Tone River system with more than 600m altitude and have heavy snowfall (Fig. 1). However, pustulosa is also found at Sebayashi of Tano-gun in the southwest Gumma. 7. The true host plant of pustulosa is the thistle (Cirsium nipponicum (MAXIM.) MAKINO var. incomptum (FR. et SAV.) KITAM. belonging to Compositae in Gumma-pref., but the beetle eats sometimes the Solanaceous plants espe-cially potato-plant. With an exceptional case the authors observed that the adults were attacking burdock leaves. 8. The distribution of sparsa is expanding northwardly year after year in Kanto District and the northern limit of the distribution runs along the line denoted in Fig. 3 and 4 at present. 9. This phenomenon is not only noticeable for ecological problem, but also very important for agriculture because the beetle probably gives a fear of attacking the Solanaceous vegetables as a new pest in the new habitats.ArticleJournal of the Faculty of Textile Science and Technology, Shinshu University. Ser. A, Biology 13: 1-23(1964)departmental bulletin pape

    Functional Evaluation of Bubble CPAP for Neonates Using a Leak Model

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    ArticleäżĄć·žćŒ»ć­Šé›‘èȘŒ 61(2):65-73(2013)journal articl

    RegionĂĄlis fejlesztĂ©spolitikai hatĂĄselemzĂ©s tĂ©rbeli szĂĄmĂ­thatĂł ĂĄltalĂĄnos egyensĂșlyi modellel: a Gmr-MagyarorszĂĄg SCGE modellje

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    A tĂ©rbeli szĂĄmĂ­thatĂł ĂĄltalĂĄnos egyensĂșlyi (SCGE) modellek az Ășj gazdasĂĄgföldrajz (ÚGF) „empirikus megfelelĂ”i”. SzemlĂ©leti-mĂłdszertani gyökereiket tehĂĄt az Ășj gazdasĂĄgföldrajzi Ă©s a szĂĄmĂ­thatĂł ĂĄltalĂĄnos egyensĂșlyi (CGE) modellekben talĂĄljuk meg. TanulmĂĄnyunkban a Nemzeti FejlesztĂ©si ÜgynöksĂ©g rĂ©szĂ©re az Új MagyarorszĂĄg FejlesztĂ©si Terv hatĂĄselemzĂ©sĂ©re kidolgozott GMR-MagyarorszĂĄg modell-rendszerbe Ă©pĂ­tett SCGE modellt ismertetjĂŒk, valamint egy szimulĂĄciĂłval illusztrĂĄljuk a modell hasznĂĄlatĂĄt.SCGE modelling, computable general equilibrium models, new economic geography, GMR-Hungary

    Laboratory-based X-ray phase-imaging scanner using Talbot-Lau interferometer for non-destructive testing

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    An X-ray Talbot-Lau interferometer scanning setup consisting of three transmission gratings, a laboratory-based X-ray source that emits X-rays vertically, and an image detector on the top has been developed for the application of X-ray phase imaging to moving objects that cannot be tested clearly with conventional absorption contrast. The grating-based X-ray phase imaging method usually employs a phase-stepping (or fringe-scanning) technique by displacing one of the gratings step-by-step while the object stays still. Since this approach is not compatible with a scanner-type application for moving objects, we have developed a new algorithm for achieving the function of phase-stepping without grating displacement. By analyzing the movie of the moirĂ© pattern as the object moves across the field of view, we obtain the absorption, differential phase, and visibility images. The feasibility of the X-ray phase imaging scanner has been successfully demonstrated for a long sample moving at 5 mm/s. This achievement is a breakthrough for the practical industrial application of X-ray phase imaging for screening objects carried on belt-conveyers such as those in factories

    Constraint-aware Policy for Compliant Manipulation

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    Robot manipulation in a physically-constrained environment requires compliant manipulation. Compliant manipulation is a manipulation skill to adjust hand motion based on the force imposed by the environment. Recently, reinforcement learning (RL) has been applied to solve household operations involving compliant manipulation. However, previous RL methods have primarily focused on designing a policy for a specific operation that limits their applicability and requires separate training for every new operation. We propose a constraint-aware policy that is applicable to various unseen manipulations by grouping several manipulations together based on the type of physical constraint involved. The type of physical constraint determines the characteristic of the imposed force direction; thus, a generalized policy is trained in the environment and reward designed on the basis of this characteristic. This paper focuses on two types of physical constraints: prismatic and revolute joints. Experiments demonstrated that the same policy could successfully execute various compliant-manipulation operations, both in the simulation and reality. We believe this study is the first step toward realizing a generalized household-robot

    A Thermophilic Alkalophilic α-Amylase from Bacillussp. AAH-31 Shows a Novel Domain Organization among Glycoside Hydrolase Family 13 Enzymes

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    α-Amylases (EC 3.2.1.1) hydrolyze internal α-1,4-glucosidic linkages of starch and related glucans. Bacillus sp. AAH-31 produces an alkalophilic thermophilic α-amylase (AmyL) of higher molecular mass, 91 kDa, than typical bacterial α-amylases. In this study, the AmyL gene was cloned to determine its primary structure, and the recombinant enzyme, produced in Escherichia coli, was characterized. AmyL shows no hydrolytic activity towards pullulan, but the central region of AmyL (Gly395-Asp684) was similar to neopullulanase-like α-amylases. In contrast to known neopullulanase-like α-amylases, the N-terminal region (Gln29-Phe102) of AmyL was similar to carbohydrate-binding module family 20 (CBM20), which is involved in the binding of enzymes to starch granules. Recombinant AmyL showed more than 95% of its maximum activity in a pH range of 8.2-10.5, and was stable below 65 °C and from pH 6.4 to 11.9. The kcat values for soluble starch, γ-cyclodextrin, and maltotriose were 103 s(-1), 67.6 s(-1), and 5.33 s(-1), respectively, and the Km values were 0.100 mg/mL, 0.348 mM, and 2.06 mM, respectively. Recombinant AmyL did not bind to starch granules. But the substitution of Trp45 and Trp84, conserved in site 1 of CBM20, with Ala reduced affinity to soluble starch, while the mutations did not affect affinity for oligosaccharides. Substitution of Trp61, conserved in site 2 of CBM20, with Ala enhanced hydrolytic activity towards soluble starch, indicating that site 2 of AmyL does not contribute to binding to soluble long-chain substrates
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