A new strategy for the synthesis of dinucleotides loaded with glycosylated amino acids--investigations on in vitro non-natural amino acid mutagenesis for glycoprotein synthesis

The in vitro non-natural amino acid mutagenesis method provides the opportunity to introduce non-natural amino acids site-specifically into proteins. To this end, a chemically synthesised aminoacylated dinucleotide is enzymatically ligated to a truncated suppressor transfer RNA. The loaded suppressor tRNA is then used in translation reactions to read an internal stop codon. Here we report an advanced and general strategy for the synthesis of the aminoacyl dinucleotide. The protecting group pattern developed for the dinucleotide facilitates highly efficient aminoacylation, followed by one-step global deprotection. The strategy was applied to the synthesis of dinucleotides loaded with 2-acetamido-2-deoxy-glycosylated amino acids, including N- and O-beta-glycosides and O- and C-alpha-glycosides of amino acids, thus enabling the extension of in vitro non-natural amino acid mutagenesis towards the synthesis of natural glycoproteins of high biological interest. We demonstrate the incorporation of the glycosylamino acids--although with low suppression efficiency--into the human interleukin granulocyte-colony stimulating factor (hG-CSF), as verified by the ELISA technique.     

Relationship between pressure units

Consultation

Relationship between pressure units     

Frequency-dependent behaviour of an acoustic-surface-wave multistrip coupler

The distribution of acoustic intensity within a surface-wave multistrip coupler on lithium niobate has been observed using a laser probe. The number of metal strips required for complete transfer of energy between coupled tracks has been determined as a function of acoustic frequency. Two stopbands were observed in the frequency range explored. A simple analytic expression is presented which is in good agreement with experiment away from the vicinity of the stopbands. It may be regarded as useful for coupler design; it is used to demonstrate that the 3 dB fractional bandwidth of the coupler may exceed 120%.     

MODEL REFERENCE ADAPTIVE CONTROL BASED ON LIAPUNOV'S DIRECT METHOD Part II: Hybrid Computer Simulation and Experimental Application

A Model Reference Adaptive Control (MRAC) system is evaluated via hybrid computer simulation and experimental application to a computer-controlled, pilot plant evaporator. In both the simulation and experimental studies, the MRAC system performed well and was insensitive to unmeasured process disturbances, to the choice of the initial control policy and to changes in plant operating conditions. In addition to providing an algorithm for adapting control systems to accommodate changing process parameters, MRAC also provides a systematic approach for tuning or developing multivariable control systems for time-invariant processes.     

Evaluation of Phase-Commutated Converters for Slip-Power Control in Induction Drives

Three different phase-commutation thyristor bridges are applied to slip-power control of an induction motor. The performance of the drive is experimentally evaluated for each thyristor bridge with respect to input power factor, efficiency, total. input current, size of the dc-link inductor, and regulation. The best results are obtained with the eight-thyristor bridge while the conventional six-thyristor converter offers the worst overall performance.     

Personality and performance characteristics associated with cigarette smoking among college freshmen.

Habitual cigarette smokers were located in a group of 2321 university freshmen. Smoking was related to both sex and social class. Matched samples of 401 smokers and nonsmokers were compared on a series of 70 dependent variables. Smokers were significantly lower in (1) cognitive ability, (2) high school and college grades, (3) 2 self-report health indices, (4) self-esteem, (5) work-motivation, and (6) attitudes toward men. The smokers scored higher on semiprojective measures of orality, social confidence, and acceptance of ambiguity. Data were most consistent with the stimulus hunger theory of smoking motivation. (24 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

High-resolution and analytical transmission electron microscopy of epitaxial YBa2Cu3O7−x thin films and YBa2Cu3O7/PrBa2Cu3O7 superlattices

Transmission electron microscopy (TEM) studies of epitaxial YBa₂Cu₃O_7−x thin films and YBa₂Cu₃O₇/PrBa₂Cu₃O₇ superlattices are summarized. High-resolution imaging of cross-sections and plan views and energy-dispersive X-ray microanalysis and electron energy loss spectroscopy in the transmission electron microscope were the methods applied. In the first section results on YBa₂Cu₃O_7−x thin films With varying oxygen stoichiometry deposited onto SrTiO₃ are discussed. Then, YBa₂Cu₃O₇/PrBa₂Cu₃O₇ superlattices deposited onto SrTiO₃ and MgO are investigated. Finally, an interface analysis of high-quality YBa₂Cu₃O_7−x thin films deposited onto sapphire with yttrium-stabilized zirconia buffer layers is presented.     

A suicide by thiopentone injection

Post-mortem tissues from a thiopentone suicide were analysed by ultraviolet spectrometry and gas chromatography. The thiopentone concentrations found (0.6 mg/100 ml of blood and 2 6 mg/100 g of tissue) are consistent with those reported for 'anaesthetic' deaths where only thiopentone and other anaesthetic agents were present. The gas chromatographic method gave more accurate result with the tissues.