Publications by authors named "Katarzyna Bielska"

We present the results of the spectral line-shape study of the first measurement of the extremely weak (7-0) band of the CO molecule. Measurements were done with a highly sensitive cavity ring-down spectrometer. Collisional narrowing, analyzed in terms of speed-dependent effects, was observed for the first time for transitions with line intensities below 2⋅10 cm/molecule at 296 K.

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The air-broadened lines from the oxygen B band were measured for the first time in controlled laboratory conditions with a high signal-to-noise ratio using frequency-stabilized cavity ring-down spectroscopy (FS-CRDS) referenced to the optical frequency comb. Spectra measured at various pressures and temperatures were analyzed with an advanced line-shape model, considering the speed-dependence of collisional broadening and shift, and the effect of velocity-changing collisions. The temperature dependence of collisional broadening and shift is determined, whereas no significant temperature dependence of speed-dependent parameters and Dicke narrowing was observed.

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Intensities of 14 lines in the sixth overtone (7-0) band of carbon monoxide (12C16O) are measured in the visible range between 14 300 and 14 500 cm-1 using a frequency-stabilized cavity ring-down spectrometer. This is the first observation of such a high and weak overtone spectrum of the CO molecule. A theoretical model is constructed and tested based on the use of a high accuracy ab initio dipole moment curve and a semi-empirical potential energy curve.

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Intensities of lines in the near-infrared second overtone band (3-0) of ^{12}C^{16}O are measured and calculated to an unprecedented degree of precision and accuracy. Agreement between theory and experiment to better than 1‰ is demonstrated by results from two laboratories involving two independent absorption- and dispersion-based cavity-enhanced techniques. Similarly, independent Fourier transform spectroscopy measurements of stronger lines in this band yield mutual agreement and consistency with theory at the 1‰ level.

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We present the results of direct measurements of the line mixing parameters for two pairs of overlapping transitions at the band head of the oxygen B band. Measurements were performed with the frequency-stabilized cavity ring-down spectrometer assisted by an optical frequency comb. The recorded spectra were analyzed with line profiles comprising speed dependence, Dicke narrowing, and line mixing.

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Frequency-based cavity mode-dispersion spectroscopy (CMDS), previously applied for Doppler-limited molecular spectroscopy, is now employed for the first time for saturation spectroscopy. Comparison with two intensity-based, cavity-enhanced absorption spectroscopy techniques, i.e.

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A spectroscopic method free from systematic errors is desired for many challenging applications of gas detection. Although existing cavity-enhanced techniques exhibit very high precision, their accuracy strongly depends on propagation of the light amplitude through an optical system and its detection. Here, we demonstrate that the frequency-based molecular dispersion spectroscopy, involving sub-Hz-level precision in frequency measurements of optical cavity resonances, leads to sub-per-mille accuracy and a wide dynamic range, both previously unattainable by any other spectroscopic technique.

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The response of an optical cavity to incomplete extinction of nearly resonant incident light was experimentally examined. Measurements were performed using a Pound-Drever-Hall-locked frequency-stabilized cavity ring-down spectrometer (CRDS) that allowed the laser frequency detuning from the cavity resonance center to be controlled at Hz-level resolution. It is shown that an insufficient laser light extinction ratio combined with a phase shift and frequency detuning may lead to non-exponential cavity pumping and decay signals.

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Atmospheric CO(2) concentrations are being closely monitored by remote sensing experiments which rely on knowing line intensities with an uncertainty of 0.5% or better. Most available laboratory measurements have uncertainties much larger than this.

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The purpose of the research was to study kindergarteners' exposition to environmental tobacco smoke (ETS) in houses. Social and economical factors were checked for the improper behavior of grown-up household. Material for the research were data collected from questionnaires filled by children's parents.

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The 20-hydroxyecdysone receptor (EcR) is a transcription factor belonging to the nuclear receptor superfamily. Together with the ultraspiracle nuclear receptor (Usp) it coordinates critical biological processes in insects such as development and reproduction. EcR and its ligands are used in commercially available ecdysone-inducible expression systems and are considered to be artificial gene switches with potential therapeutic applications.

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The ultraspiracle protein (Usp), together with an ecdysone receptor (EcR) forms a heterodimeric ecdysteroid receptor complex, which controls metamorphosis in Drosophila melanogaster. Although the ecdysteroid receptor is considered to be a source of elements for ecdysteroid inducible gene switches in mammals, nothing is known about posttranslational modifications of the receptor constituents in mammalian cells. Up until now there has been no study about Usp sumoylation.

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Frequency-stabilized cavity ring-down spectroscopy (FS-CRDS) was employed to measure air-broadened CO(2) line shape parameters for transitions near 1.6 μm over a pressure range of 6.7-33 kPa.

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