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Dynamics of visible-to-ultraviolet upconversion in YAlO3: 1% Er3+
The dynamics of visible-to-ultraviolet upconversion in YAlO3: 1% Er3+ crystal has been investigated using the time-resolved laser spectroscopy when the sample was excited into the S-4(3/2) multiplets. It is found that the upconverted luminescence is produced by energy-transfer upconversion or by excited-state absorption depending on the excitation wavelength. The dependence of upconverted luminesc
A Bode sensitivity integral for linear time-periodic systems
For linear time-invariant systems Bode's sensitivity integral is a well-known formula that quantifies some of thelimitations in feedback control. In this paper we show that a very similar formula holds for linear time-periodicsystems. We use the infinite-dimensional frequency-response operator called the harmonic transfer function to prove the result. It is shown that the harmonic transfer functio
Expression of double Vitreoscilla hemoglobin enhances growth and alters ribosome and tRNA levels in Escherichia coli
In several organisms, expression of a gene encoding dimeric hemoglobin (VHb) from the obligate aerobic bacterium Vatreoscilla stercoraria has been shown to increase microaerobic cell growth and enhance oxygen-dependent cell metabolism. In an attempt to further improve these effects of VHb, a gene encoding two vhb genes connected by a short linker of six base pairs was constructed and expressed in
Analysis of strongly interfering slow frequency-hopping systems
In this report slow frequency-hopping systems are analyzed with respect to the probability of successful transmission of packets, and with respect to the throughput. It is assumed that collisions result in a loss of all information contained in the colliding packets, irrespective of the distance between the units of the system. Units transmit packets of different types with a certain probability,
GUTI: a new antigen in the Cromer blood group system
BACKGROUND: The Cromer blood group system consists of seven high-incidence and three low-incidence antigens carried on decay-accelerating factor (DAF). This report describes the identification and characterization of a new Cromer high-incidence antigen, named GUTI. STUDY DESIGN AND METHODS: RT-PCR and sequence analysis were performed on cDNA prepared from a Chilean donor whose serum contained the
Experimental and theoretical study of core-excited states of Al III
Chloride concentration in preloaded compact tension concrete specimens
Polyelectrolytes
The Soviet Union and Peacetime Neutrality in Europe : A Study of Soviet Political Language
The influence of lithium on the antidiuretic effect of desmopressin.
The objective of this study was to investigate the graded influence from lithium on the antidiuretic effects of desmopressin. Eight healthy male subjects participated in this open, randomised cross-over study with two periods comprising 6 days each. For each subject, one of the study days (6th day) was preceded by a period of lithium treatment. On the study days the subjects were orally water load
Activity, use of technical devices and prostheses among persons lacking one hand
Isomeric decays in neutron-rich W, Os and Pt nuclei
Relativistic energy fragmentation of a 1 GeV/nucleon Pb-208 beam was used to populate a wide range of nuclei on both sides of the valley of beta-stability. The structure of these nuclei was studied by the identification of discrete gamma-ray transitions depopulating isomeric states with lifetimes in the nano- to millisecond range. Highlights of the experiment include the first observation of gamma
Efficient first-order performance estimation for high-order adaptive optics systems
It is shown how first-order performance estimation of high-orderadaptive optics (AO) systems may be efficiently implemented in a hybridnumerical simulation by the use of 1) sparse matrix techniques forwavefront reconstruction, 2) undersampled pupil-plane turbulence-inducedaberrations, and 3) analytical models that compensate - in the limit ofinfinite exposure time - for the errors introduced by un
The effect of assembly tolerance on performance of a tape application task: A pilot study
Task characteristics such as visual and manual demands influence the postures employed and the muscular load during task execution. According to ergonomic experts at a car assembly plant, these demands are difficult to predict during product and production development and can easily be underestimated. One such task with combined visual and manual demands is the application of deco-tape to the door
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Nonsense-mediated mRNA decay in barley mutants allows the cloning of mutated genes by a microarray approach.
We have previously described a microarray approach to identify and clone genes from mutants of higher organisms. In the method cDNA of two mutants with similar phenotype are competitively hybridized to DNA clones arrayed on a glass slide. Clones corresponding to an mRNA that is not expressed in one of the strains due to a mutation will be specifically highlighted in the hybridization, which provid
Estimating the Two-Dimensional Coherence Function
In this paper, we extend the one-dimensional Capon-based magnitude square coherence (MSC) spectral estimator, to form two-dimensional Capon- and APES-based MSC spectral estimators. The resulting estimators are found to yield significantly improved estimates as compared to the typical Welch-based estimator. Furthermore, we introduce a computationally efficient time-updating of the presented MSC est
Tracking ultrafast excited-state bond-twisting motion in solution close to the Franck-Condon point
Applying optimal control to photoinduced trans-cis isomerization in condensed phase, the dynamics of bond-twisting motion of 1,1'-diethyl-4,4'-cyanine in methanol and propanol is revealed. The shape of the optimized pulse resulting from minimization of the photoisomer formation can be directly related to the initial excited-state dynamics in close proximity to the Franck-Condon point. The solvent
Color constancy in visual scene perception
In RoboCup, all objects in the game are color coded to allow easy segmentation and identification. However, color vision is very sensitive to the exact color of the illumination which makes the identification task much harder than is often anticipated. Algorithms that work in the lab in fluorescent light may not function at all in an actual game where incandescent lights are used. This article is