595 research outputs found

    A New Possibility of Dynamical Study on Solid State Ionic Materials by Inelastic Neutron Scattering

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    A new technique of inelastic neutron scattering measurement utilizing the multiple incident energies is applied to the dynamical study of vitreous silica. A wide variety of extracted information from a series of two-dimensional maps of dynamical structure factor with multiple different incident energies are greatly valuable. The applicability and its expected contribution of new experimental technique into the further progress of scientific activities in solid state ionic materials are discussed.Received: 30 September 2010; Revised: 25 October 2010; Accepted: 26 October 201

    Rancangan Mesin Pembelah Buah Pinang dengan Dua Mata Potong

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    Betel nut palm plant is one of the many benefits and efficacy, especially seeds. Areca nuts are widely used as the main raw material in the process of making drugs, cosmetics, slimming, snacks, sweets, and coffee. Betel nut processing into betel nut is still constrained by the tool is still modest, are still using wood beams repose knife to split betel nut into two parts. To overcome these problems needed betel nut splitter machine with a capacity of 250 kg / h. This engine design is expected to help farmers during the process of betel nut processing into dried betel nut. The working principle of betel nut splitter machine originated from an electric motor that produces rotation is forwarded to the reducer and to the cutting blade associated with two gears. Betel nut is inserted through the insertion funnel towards the rotor has 4 channels / trench, and rotor spinning and crashing betel nut rotating blades reversed so the rotor besidesbetel nut split into two parts. Shaft rotation speed at the eye-piece and carrier rotor shaft is 9.32 rpm, the rotation speed is obtained from the ratio gearbox and pulley on the engine splitter ratio. With the machine is expected to help farmers to cultivate betel nut, so the work is lighter, faster and may prevent accidents. Shaft rotation speed at the eye-piece and carrier rotor shaft is 9.32 rpm, the rotation speed is obtained from the ratio gearbox and pulley on the engine splitter ratio. With the machine is expected to help farmers to cultivate betel nut, so the work is lighter, faster and may prevent accidents. Shaft rotation speed at the eye-piece and carrier rotor shaft is 9.32 rpm, the rotation speed is obtained from the ratio gearbox and pulley on the engine splitter ratio. With the machine is expected to help farmers to cultivate betel nut, so the work is lighter, faster and may prevent accidents

    ICER is requisite for Th17 differentiation.

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    Inducible cAMP early repressor (ICER) has been described as a transcriptional repressor isoform of the cAMP response element modulator (CREM). Here we report that ICER is predominantly expressed in Th17 cells through the IL-6-STAT3 pathway and binds to the Il17a promoter, where it facilitates the accumulation of the canonical enhancer RORγt. In vitro differentiation from naive ICER/CREM-deficient CD4(+) T cells to Th17 cells is impaired but can be rescued by forced overexpression of ICER. Consistent with a role of Th17 cells in autoimmune and inflammatory diseases, ICER/CREM-deficient B6.lpr mice are protected from developing autoimmunity. Similarly, both anti-glomerular basement membrane-induced glomerulonephritis and experimental encephalomyelitis are attenuated in ICER/CREM-deficient mice compared with their ICER/CREM-sufficient littermates. Importantly, we find ICER overexpressed in CD4(+) T cells from patients with systemic lupus erythematosus. Collectively, our findings identify a unique role for ICER, which affects both organ-specific and systemic autoimmunity in a Th17-dependent manner

    Crystal Structure of the Formin mDia1 in Autoinhibited Conformation

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    Formin proteins utilize a conserved formin homology 2 (FH2) domain to nucleate new actin filaments. In mammalian diaphanous-related formins (DRFs) the FH2 domain is inhibited through an unknown mechanism by intramolecular binding of the diaphanous autoinhibitory domain (DAD) and the diaphanous inhibitory domain (DID).Here we report the crystal structure of a complex between DID and FH2-DAD fragments of the mammalian DRF, mDia1 (mammalian diaphanous 1 also called Drf1 or p140mDia). The structure shows a tetrameric configuration (4 FH2 + 4 DID) in which the actin-binding sites on the FH2 domain are sterically occluded. However biochemical data suggest the full-length mDia1 is a dimer in solution (2 FH2 + 2 DID). Based on the crystal structure, we have generated possible dimer models and found that architectures of all of these models are incompatible with binding to actin filament but not to actin monomer. Furthermore, we show that the minimal functional monomeric unit in the FH2 domain, termed the bridge element, can be inhibited by isolated monomeric DID. NMR data on the bridge-DID system revealed that at least one of the two actin-binding sites on the bridge element is accessible to actin monomer in the inhibited state.Our findings suggest that autoinhibition in the native DRF dimer involves steric hindrance with the actin filament. Although the structure of a full-length DRF would be required for clarification of the presented models, our work here provides the first structural insights into the mechanism of the DRF autoinhibition

    Rhodobacter capsulatus forms a compact crescent-shaped LH1–RC photocomplex

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    Rhodobacter (Rba.) capsulatus has been a favored model for studies of all aspects of bacterial photosynthesis. This purple phototroph contains PufX, a polypeptide crucial for dimerization of the light-harvesting 1–reaction center (LH1–RC) complex, but lacks protein-U, a U-shaped polypeptide in the LH1–RC of its close relative Rba. sphaeroides. Here we present a cryo-EM structure of the Rba. capsulatus LH1–RC purified by DEAE chromatography. The crescent-shaped LH1–RC exhibits a compact structure containing only 10 LH1 αβ-subunits. Four αβ-subunits corresponding to those adjacent to protein-U in Rba. sphaeroides were absent. PufX in Rba. capsulatus exhibits a unique conformation in its N-terminus that self-associates with amino acids in its own transmembrane domain and interacts with nearby polypeptides, preventing it from interacting with proteins in other complexes and forming dimeric structures. These features are discussed in relation to the minimal requirements for the formation of LH1–RC monomers and dimers, the spectroscopic behavior of both the LH1 and RC, and the bioenergetics of energy transfer from LH1 to the RC.journal articl

    Challenges facing an understanding of the nature of low-energy excited states in photosynthesis

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    © 2016 Elsevier B.V. While the majority of the photochemical states and pathways related to the biological capture of solar energy are now well understood and provide paradigms for artificial device design, additional low-energy states have been discovered in many systems with obscure origins and significance. However, as low-energy states are naively expected to be critical to function, these observations pose important challenges. A review of known properties of low energy states covering eight photochemical systems, and options for their interpretation, are presented. A concerted experimental and theoretical research strategy is suggested and outlined, this being aimed at providing a fully comprehensive understanding
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