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101.
Andrea Funke Beatrice Karg Dr. Jonathan Dickerhoff Dr. Darko Balke Prof. Dr. Sabine Müller Prof. Dr. Klaus Weisz 《Chembiochem : a European journal of chemical biology》2018,19(5):505-512
Binding of an indoloquinoline derivative with an aminoalkyl side chain to a truncated sequence from the MYC promoter region was studied through isothermal titration calorimetry (ITC). The targeted MYC3 sequence lacks 3′‐flanking nucleotides and forms a monomeric parallel quadruplex (G4) with a blunt‐ended 3′‐outer tetrad under the solution conditions employed. Analysis of ITC isotherms reveals multiple binding equilibria with the initial formation of a 1:2 ligand/quadruplex complex. Evaluation of electrophoretic mobilities as well as NMR spectral data confirm ligand‐induced dimerization of MYC3 quadruplexes with the ligand sandwiched between the two 3′‐outer tetrads. Additional ligand molecules in excess bind to the 5′‐outer tetrads of the sandwich complex. Such a ligand‐promoted G4 dimerization may be exploited for the controlled assembly or disassembly of G4 aggregates to expand on present quadruplex‐based technologies. 相似文献
102.
Microstructural changes occurring during oxidation of the reduced form of donor-doped BaTiO3 (Ba1− X D X . Ti1− X 4+ Ti X 3+ O3 ) and during reduction of the oxidized form of donor-doped BaTiO3 (Ba1− X D X . Ti1− X /4 4+ ( V Ti ) X /4 O3 ) were studied using TEM. Samples of both types of solid solutions, containing different La concentrations (from 2 to 20 mol% La), were prepared by sintering under reducing conditions and in air, respectively. The reduced form of donor-doped BaTiO3 was oxidized by annealing at high temperatures (1150° and 1350°C) in air, while the oxidized form was reduced by annealing under reducing conditions. Because of oxidation of the reduced phase of donor-doped BaTiO3 , the Ti-rich phases Ba6 Ti17 O40 and BaLa2 Ti4 O12 were precipitated. Reduction of the oxidized form caused precipitation of the Ba-rich phase Ba2 TiO4 preferentially inside the matrix grains. All precipitates had well-defined orientational relationships with the perovskite matrix. 相似文献
103.
104.
Darko Frank Heikki Remes Jani Romanoff 《Fatigue & Fracture of Engineering Materials & Structures》2013,36(12):1336-1351
The paper investigates the influence of highly localised stress distribution around the notch tips of the laser stake‐welded T‐joints to the slope of the fatigue resistance curve. The study considers experimental data of eight series involving joints under tension or bending loads. Various boundary conditions and plate thicknesses are considered. The stress distribution in the singularity‐dominated zone ahead of the notch tips is investigated by means of the finite element analysis. The aim is to relatively distinguish the stress distribution from one case to another. The growth rate of the elastic singular stress with respect to the distance from the tip is described by the dimensionless gradient. This gradient is equal to the slope of the linear stress‐distance function when presented in double‐logarithmic scale. The slope of the fatigue resistance curve varies approximately from 4 to 8. It is observed that the change of the slope can be closely associated with the gradient of the maximum principal stress evaluated in the plane that is orthogonal to the crack path. The orthogonal plane corresponds to the maximum principal stress direction. In contrast, there is a large scatter in the relation between the slope and the gradient evaluated in the commonly assumed crack plane. The study shows that the dimensionless gradient exhibits sensitivity towards plate thicknesses, local weld geometry and the loading condition. 相似文献
105.
Veberič D 《Applied optics》2012,51(2):139-147
We present a novel method for combining the analog and photon-counting measurements of lidar transient recorders into reconstructed photon returns. The method takes into account the statistical properties of the two measurement modes and estimates the most likely number of arriving photons and the most likely values of acquisition parameters describing the two measurement modes. It extends and improves the standard combining ("gluing") methods and does not rely on any ad hoc definitions of the overlap region nor on any background subtraction methods. 相似文献
106.
Condition-based spares ordering for critical components 总被引:2,自引:0,他引:2
Darko LouitRodrigo Pascual Dragan BanjevicAndrew K.S. Jardine 《Mechanical Systems and Signal Processing》2011,25(5):1837-1848
It is widely accepted that one of the potential benefits of condition-based maintenance (CBM) is the expected decrease in inventory as the procurement of parts can be triggered by the identification of a potential failure. For this to be possible, the interval between the identification of the potential failure and the occurrence of a functional failure (P-F interval) needs to be longer than the lead time for the required part. In this paper we present a model directed to the determination of the ordering decision for a spare part when the component in operation is subject to a condition monitoring program. In our model the ordering decision depends on the remaining useful life (RUL) estimation obtained through (i) the assessment of component age and (ii) condition indicators (covariates) that are indicative of the state of health of the component, at every inspection time. We consider a random lead time for spares, and a single-component, single-spare configuration that is not uncommon for very expensive and highly critical equipment. 相似文献
107.
Ovidiu Ivanciuc Darko Babi Alexandra T. Balabana 《Fullerenes, Nanotubes and Carbon Nanostructures》1999,7(1):1-15
By selecting 5 or 6 parameters from the 14 possible topological parameters referring to the disposition of the 5- and 6-membered rings around each edge in a proper fullerene with isolated pentagons, it is possible to obtain good correlations with calculated (MM+) energies of fullerenes. The correlations were tested on all isomers of IPR fullerenes with 94 to 100 carbon atoms, and standard deviations around 2.5 kcal/mol were obtained. 相似文献
108.
Božo Smoljan Franjo Cajner Darko Landek 《Journal of Materials Engineering and Performance》2002,11(3):278-282
Achievements of the induction hardening of ferritic ductile iron were investigated. Ductile iron is not advisable for use
in induction hardening because of the small carbon content in the metal matrix of ferritic ductile iron. The carbon content
in the metal matrix of ductile iron can be increased by additional preparation of metal matrix before final induction heat
hardening. Wear resistance of the induction hardened ferritic ductile iron can increase as result of increased carbon content
of the metal matrix and higher hardness after induction hardening. Some heat pretreatments for metal matrix preparation were
applied before the induction hardening of ferritic ductile iron. The process parameters of the induction hardening heat pretreatment
were analyzed and optimized. According to recommended elemental composition of ferritic ductile iron and required mechanical
properties, the process parameters of the investigated induction heat pretreatment were optimized. The efficiency of pretreatment
processes of induction hardening was analyzed. Applicability and manufacture ability of engineering components by proposed
heat pretreatments were investigated. The limitations of the investigated heat pretreatment applications were estimated by
the comparison of mechanical properties of heat-treated specimens. 相似文献
109.
Published studies on low-frequency (10 Hz–100 kHz) electromagnetic measurements of oil-well steel casing properties are mainly experimental and focus on certain regions of the space and frequency distributions of an exciter magnetic field inside a casing. We present an analytical model, based on the work of Dodd and Deeds, and employ it to analyse the whole space–frequency characteristic. We show that the model predictions and sensitivity analysis are consistent with the known effects of coil separation and excitation frequency on the measurements. The modelled responses to pulsed excitation are in good quantitative agreement with the experiments. The model can be applied in optimal design of the measurement systems and model-based measurement of the casing properties. 相似文献
110.