Static random-access memory (SRAM) is an essential component for realizing large-scale integration (LSI). The future transition to a 48 V DC supply in datacenters and electric vehicles acting as ...mobile edge servers will increase the demand for a bipolar-complementary metal-oxide semiconductor-double diffused metal-oxide semiconductor with high-capacity SRAM. When we scaled and optimized an SRAM cell from 130 nm nodes to 90 nm nodes, we observed the generation of crystal defects induced by mechanical stress in the p-channel MOS active area that cannot be explained by previous models. We performed simulations using the finite element method to identify the mechanism. In our results, the edge of the narrow active area showed a large deformation compared to the middle of the active area, which can be attributed to compressive stress from the gate electrode and sidewall. The cell layout and sidewall structure were optimized to suppress this defect generation while satisfying reliability requirements, and the design can be extended to 65 nm nodes.
The basidiomycete Coprinopsis cinerea produces five cellobiohydrolases belonging to glycoside hydrolase family 6 (GH6). Among these enzymes, C. cinerea cellulase 6C (CcCel6C), but not C. cinerea ...cellulase 6A (CcCel6A), can efficiently hydrolyze carboxymethyl cellulose and is constitutively expressed in C. cinerea. In contrast, CcCel6A possesses a cellulose‐binding domain, and is strongly induced by cellobiose. Here, we determined the crystal structures of the CcCel6A catalytic domain complexed with a Hepes buffer molecule, with cellobiose, and with p‐nitrophenyl β‐d‐cellotrioside (pNPG3). A notable feature of the GH6 cellobiohydrolases is that the active site is enclosed by two loops to form a tunnel, and the loops have been demonstrated to open and close in response to ligand binding. The enclosed tunnel of CcCel6A–Hepes is seen as the open form, whereas the tunnels of CcCel6A–cellobiose and CcCel6A–pNPG3 adopt the closed form. pNPG3 was not hydrolyzed by CcCel6A, and bound in subsites +1 to +4. On the basis of this observation, we constructed two mutants, CcCel6A D164A and CcCel6C D102A. Neither CcCel6A D164A nor CcCel6C D102A hydrolyze phosphoric acid‐swollen cellulose. We have previously determined the crystal structures of CcCel6C unbound and in complex with ligand, both of which adopt the open form. In the present study, both CcCel6A and CcCel6C mutants were identified as the closed form. However, the motion angle of CcCel6C was more than 10‐fold greater than that of CcCel6A. The width of the active site cleft of CcCel6C was narrowed, owing to a tweezer‐like motion.
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The coordinates and structure factors described in this article have been deposited in the Protein Data Bank under the accession codes 3VOG, 3VOH, 3VOI, 3VOJ, and 3VOF
The active site tunnel of the GH6 cellobiohydrolases adopts open and closed forms. We determined the crystal structures of wild‐type and mutant forms of CcCel6A catalytic domain, and also the CcCel6C mutant. The results indicated that the angle of the open‐to‐closed motion of CcCel6C was more than 10‐fold greater than that of CcCel6A.
•The structure of the N-terminal domain of a GH131 protein was determined.•The structure is composed of a β-jelly roll fold.•The possible active site is wide and shallow.•Arg96, Glu98, Glu138, and ...His218 are likely to be catalytically critical.•The catalytic mechanism could be different from that of typical glycosidases.
The crystal structure of the N-terminal putative catalytic domain of a glycoside hydrolase family 131 protein from Coprinopsis cinerea (CcGH131A) was determined. The structure of CcGH131A was found to be composed of a β-jelly roll fold and mainly consisted of two β-sheets, sheet-A and sheet-B. A concave of sheet-B, the possible active site, was wide and shallow, and three glycerol molecules were present in the concave. Arg96, Glu98, Glu138, and His218 are likely to be catalytically critical residues, and it was suggested that the catalytic mechanism of CcGH131A is different from that of typical glycosidases.
The basidiomycete Coprinopsiscinerea produces five cellobiohydrolases belonging to glycoside hydrolase family6 (GH6). Among these enzymes, C.cinerea cellulase6C (CcCel6C), but not C.cinerea ...cellulase6A (CcCel6A), can efficiently hydrolyze carboxymethyl cellulose and is constitutively expressed in C.cinerea. In contrast, CcCel6A possesses a cellulose-binding domain, and is strongly induced by cellobiose. Here, we determined the crystal structures of the CcCel6A catalytic domain complexed with a Hepes buffer molecule, with cellobiose, and with p-nitrophenyl beta-d-cellotrioside (pNPG3). A notable feature of the GH6 cellobiohydrolases is that the active site is enclosed by two loops to form a tunnel, and the loops have been demonstrated to open and close in response to ligand binding. The enclosed tunnel of CcCel6A-Hepes is seen as the open form, whereas the tunnels of CcCel6A-cellobiose and CcCel6A-pNPG3 adopt the closed form. pNPG3 was not hydrolyzed by CcCel6A, and bound in subsites +1 to +4. On the basis of this observation, we constructed two mutants, CcCel6AD164A and CcCel6CD102A. Neither CcCel6AD164A nor CcCel6CD102A hydrolyze phosphoric acid-swollen cellulose. We have previously determined the crystal structures of CcCel6C unbound and in complex with ligand, both of which adopt the open form. In the present study, both CcCel6A and CcCel6C mutants were identified as the closed form. However, the motion angle of CcCel6C was more than 10-fold greater than that of CcCel6A. The width of the active site cleft of CcCel6C was narrowed, owing to a tweezer-like motion. Database The coordinates and structure factors described in this article have been deposited in the Protein Data Bank under the accession codes , , , , and PUBLICATION ABSTRACT
Flash lamp annealing (FLA) technology is proposed as a new method of activating implanted impurities. By optimizing FLA and implantation conditions, junction depth (Xj) at the concentration of 1 /spl ...times/ 10/sup 18/ cm/sup -3/ and the sheet resistance of 13 nm and 700 /spl Omega//sq for As and 14 nm and 770 /spl Omega//sq for BF/sub 2/ with junction leakage lower than 1 /spl times/ 10/sup -16/ A//spl mu/m/sup 2/ at 1.5 V were successfully obtained without wafer slip and warpage problems.
Gaining a thorough understanding of the reactions on the electrode surfaces of lithium batteries is critical for designing new electrode materials suitable for high-power, long-life operation. A ...technique for directly observing surface structural changes has been developed that employs an epitaxial LiMn2O4 thin-film model electrode and surface X-ray diffraction (SXRD). Epitaxial LiMn2O4 thin films with restricted lattice planes (111) and (110) are grown on SrTiO3 substrates by pulsed laser deposition. In situ SXRD studies have revealed dynamic structural changes that reduce the atomic symmetry at the electrode surface during the initial electrochemical reaction. The surface structural changes commence with the formation of an electric double layer, which is followed by surface reconstruction when a voltage is applied in the first charge process. Transmission electron microscopy images after 10 cycles confirm the formation of a solid electrolyte interface (SEI) layer on both the (111) and (110) surfaces and Mn dissolution from the (110) surface. The (111) surface is more stable than the (110) surface. The electrode stability of LiMn2O4 depends on the reaction rate of SEI formation and the stability of the reconstructed surface structure.
The objective of this study is to assess the global impact of sea level rise and to evaluate the effectiveness of adaptation. Global areas of inundation due to sea level rise are identified. The ...affected populations and the economic damage caused by inundation due to future climate change are estimated for a number of scenarios involving Representative Concentration Pathways (RCP) and Shared Socioeconomic Pathways (SSP). The effects of adaptation in coastal areas, specifically the effects of elevating dikes, are evaluated. According to study results, dikes 1 m in height may reduce the total inundated area by approximately 40% below the no-adaptation baseline under the same RCP. The cost of adaptation was estimated using an original cost database to establish the cost of protection in future socioeconomic scenarios. It was found that the incremental adaptation cost was less than the economic damage in almost all cases of RCP/SSP, providing an incentive to take action to respond to climate change.
Nonstoichiometric lanthanum oxyfluorides, LaO1−xF1+2x (0 ≤ x ≤ 0.5) and Sr2+-doped La1−ySryO0.6−x−0.5yF1.8+2x (0 ≤ x ≤ 0.2, 0 ≤ y ≤ 0.4), were investigated as potential candidates for fluoride ion ...(F−) conductors. Although stoichiometric LaOF has been reported to exhibit a phase transition between the tetragonal α-phase (space group: P4/nmm) and trigonal β-phase (R-3m), such a phase transition was successfully suppressed by introducing excess F− ions into the lattice of lanthanum oxyfluoride. Furthermore, the introduction of excess F− ions, also improved the-conducting properties of the oxyflouride lattice. Among the various samples investigated, it was observed that, the F− ion conductivity of La0.7Sr0.3O0.4F1.9 (x = 0.05, y = 0.3) was the highest, with a value of 2.9 × 10−4 S cm−1 at 300 °C, approximately 930 times higher than that of stoichiometric LaOF.
Nonstoichiometric rare-earth oxyfluorides (RO1−xF1+2x) were synthesized and the relationship between the crystalline phase and fluoride-ion-conducting properties were investigated. In the case of ...stoichiometric ROF (x = 0.0) except for YbOF, a trigonal structure (R 3 m) was formed, in which the RO4F4 unit was distorted as the ionic radius of R3+ decreased. The introduction of F− ions into the lanthanum oxyfluoride (LaOF) structure, which initially had the rectangular RO4F4 unit, resulted in a transformation to the tetragonal P4/nmm phase. However, in the case of nonstoichiometric RO1−xF1+2x with an increased distortion in the RO4F4 unit compared to the stoichiometric ROF (x = 0.0), lower symmetric orthorhombic Pmmn and Abm2 phases were obtained. The electrical conductivity of the RO1−xF1+2x solids is significantly influenced by their structural symmetry, and the LaO1−xF1+2x solid having the most symmetric RO4F4 units in the structure exhibited the highest ion conductivity.
Ribitol phosphate modifications to the core M3 O-mannosyl glycan are important for the functional maturation of α-dystroglycan. Three sequentially extended partial structures of the core M3 ...O-mannosyl glycan including a tandem ribitol phosphate were regio- and stereo-selectively synthesized: Rbo5P-3GalNAcβ, Rbo5P-1Rbo5P-3GalNAcβ, and Xylβ1-4Rbo5P-1Rbo5P-3GalNAcβ (Rbo5P, d-ribitol-5-phosphate; GalNAc, N-acetyl-d-galactosamine; Xyl, d-xylose). Rbo5P-3GalNAcβ with p-nitrophenyl at the aglycon part served as a substrate for ribitol phosphate transferase (FKRP, fukutin-related protein), and its product was glycosylated by the actions of a series of glycosyltransferases, namely, ribitol xylosyltransferase 1 (RXYLT1), β1,4-glucuronyltransferase 1 (B4GAT1), and like-acetyl-glucosaminyltransferase (LARGE). Rbo5P-3GalNAcβ equipped with an alkyne-type aglycon was also active for FKRP. The molecular information obtained on FKRP suggests that Rbo5P-3GalNAcβ derivatives are the minimal units required as the acceptor glycan for Rbo5P transfer and may serve as a precursor for the elongation of the core M3 O-mannosyl glycan.
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