Materials Literature
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3'-Aminoglycoside kinase type IIIa [APH(3')-IIIa] catalyzes the transfer of gamma-phosphate from ATP to the 3'-hydroxyl of many aminoglycoside antibiotics, abolishing their bactericidal effects. Despite very low sequence identity, APH(3')-IIIa and eukaryotic protein kinases share structural and functional similarities…
Dutch elm disease fungus Ophiostoma novo-ulmi contains a hydrolase activity which catalyses the resolution of racemic ethyl naproxen to the corresponding acid. The recombinant enzyme has been crystallized by the vapour-diffusion method in two crystal forms. The crystals of the first form belong to space group P2(1)2(1…
Brillouin light scattering experiments were carried out on porous silicon layers fabricated from [111]-oriented p-type crystalline silicon substrates with resistivity 0.01 Ω cm. The thickness and porosity of the layers ranged from 1.6 to 11.40 µm and 0.25 to 0.40, respectively. The only Brillouin peaks evident in the…
The superconductor $\mathrm{Mg}\mathrm{C}{\mathrm{Ni}}_{3}$ has been chemically doped by partial substitution of Ru for Ni in the solid solution $\mathrm{Mg}\mathrm{C}{\mathrm{Ni}}_{3\ensuremath{-}x}{\mathrm{Ru}}_{x}$ for $0<x<0.5$. Magnetic and specific heat measurements show that the Sommerfeld parameter $({\e…
Succinyl-CoA:3-ketoacid CoA transferase (SCOT; EC 2.8.3.5) activates the acetoacetate in ketone bodies by transferring the CoA group from succinyl-CoA to acetoacetate to produce acetoacetyl-CoA and succinate. In the reaction, a glutamate residue at the active site of the enzyme forms a thioester bond with CoA and in t…
The crystal structure of Acetobacter aceti PurE was determined to a resolution of 1.55 A and is compared with the known structures of the class I PurEs from a mesophile, Escherichia coli, and a thermophile, Thermotoga maritima. Analyses of the general factors that increase protein stability are examined as potential e…
The acidity of amorphous B 2 O 3 −SiO 2 has been investigated by infrared spectroscopy using the following three probe molecules presenting a wide range of basic strength: pyridine, acetonitrile, and carbon monoxide. The results are compared to those obtained on γ-Al 2 O 3 . No coordination of carbon monoxide is obser…
The synthesis of several UO(2)-alaskaphyrin derivatives functionalized with aliphatic chains is described. These compounds are found to be liquid-crystalline and form columnar mesophases, as judged from polarizing optical microscopy studies, and represent the first uranium-containing discotic mesogens.
Abstract The electronic structure of three model potentials for quantum dots has been studied. The potentials are of finite depth and spherical symmetry and have a range between 5 to 25 nm. The sequence of electronic states differs markedly from the one familiar from atomic systems. The occurrence of high angular mome…
We investigated poly(2,2-bis(trifluoromethyl)-4,5-difluoro-1,3-dioxide-co-tetrafluoroethylene (Teflon AF 2400, Tg = 240 degrees C), a stable and permeable fluorous polymer, as a transport/extraction medium for solutes for the first time. From the study of transport behavior of a series of solutes (in chloroform soluti…
Dihydroxyacetone (Dha) kinases are a sequence-conserved family of enzymes, which utilize two different phosphoryldonors, ATP in animals, plants, and some bacteria, and a multiphosphoprotein of the phosphoenolpyruvate carbohydrate phosphotransferase system (PTS) in most bacteria. Here, we compare the PTS-dependent kina…
PURPOSE: To investigate the duration of liver R2* enhancement and pharmacokinetics following administration of an iron oxide nanoparticle in a rat model. MATERIALS AND METHODS: Rats were injected with 0, 1, 2, or 5 mg Fe/kg of NC100150 Injection, and quantitative in vivo 1/T2* liver measurements were obtained between…
In this paper, a nonlinear theory applicable to the design of nanotube based devices is presented. The role of finite kinematics for a doubly clamped nanotube device is investigated. In particular, we analyze the continuous deformation and instability (pull in) of a clamped-clamped nanotube suspended over an electrode…
(1)H NMR spectra of three paramagnetic Ni(II) complexes of benziporphyrins have been investigated in a broad temperature range. For the m- and p-benziporphyrin complexes, the line widths of certain signals exhibit an unusual temperature dependence characteristic of a dynamic process. This behavior is interpreted in te…
Dimensionality is an important governing factor in the electronic structures of semiconductor nanocrystals. The quantum confinement energies in one-dimensional quantum wires and zero-dimensional quantum dots are quite different. Using large-scale first-principle calculations, we have systematically studied the electro…
A novel solid-state polymer electrolyte was constructed using layer-by-layer (LbL) polyelectrolyte assembly of linear poly(ethylenimine) (LPEI) and poly(acrylic acid) (PAA), combined with a plasticization step using oligoethylene glycol dicarboxylic acid (OEGDA). This composite film exhibits a relatively high ionic co…
The structure of the ${\text{Ca}}_{3}{\text{Co}}_{2}{\mathrm{O}}_{6}$ compound is made of chains on a triangular array. The intra- and interchain coupling are ferromagnetic and antiferromagnetic, respectively, and the chain itself contains a 1:1 alternation of ${\text{CoO}}_{6}$ trigonal prisms (TP) and octahedra (oct…
2-Deoxyribose-5-phosphate aldolase catalyzes a reversible aldol condensation of two aldehydes via formation of a covalent Schiff-base intermediate at the active lysine residue. The crystal structure of 2-deoxyribose-5-phosphate aldolase from Thermus thermophilus HB8 has been determined with and without the substrate a…
A new modification of Ba 2 SnTe 5 was prepared by directly reacting the elements in stoichiometric ratios at 750 °C, while the first reported modification was formed in a potassium polytelluride flux at 450 °C. The former crystallizes in a unique structure type with SnTe 4 tetrahedra, SnTe 5 trigonal bipyramids, and n…
The variations of flexural strength and flexural modulus of unsaturated polyester-based sisal/glass hybrid composites with fiber content have been studied. The hybrid composites showed an increase in flexural properties with glass fiber loading. The effects of alkali treatment and silane treatment of fibers on the fle…