Search results for "Spectrum"
showing 10 items of 2043 documents
<title>Deconvolution of the mercury 253.7 nm spectral line shape for the use in absorption spectroscopy</title>
2008
In this work we present measurement and results of the deconvolution of the Hg 253.7 nm spectral line shapes, emitted from the mercury isotope high-frequency electrodeless discharge lamps, made at the Institute of Atomic Physics and Spectroscopy for the use in Zeeman Atomic Absorption Spectrometry. The emission line profiles of 254 nm Hg resonance line have been measured by means of a Zeeman scanning spectrometer at the mercury cold spot temperature value at 20 C. Then the deconvolution procedure or solving of this ill-posed inverse problem by means of the Tikhonov's regularization method [1] was performed to obtain the real spectral line shape.© (2008) COPYRIGHT SPIE--The International Soc…
Zinc Finger Proteins in Neuro-Related Diseases Progression
2021
Zinc finger proteins (ZNF) are among the most abundant proteins in eukaryotic genomes. It contains several zinc finger domains that can selectively bind to certain DNA or RNA and associate with proteins, therefore, zinc finger proteins can regulate gene expression at the transcriptional and translational levels. In terms of neurological diseases, numerous studies have shown that many zinc finger proteins are associated with neurological diseases. The purpose of this review is to summarize the types and roles of zinc finger proteins in neuropsychiatric disorders. We will describe the structure and classification of zinc finger proteins, then focus on the pathophysiological role of zinc finge…
A Constrained Band Selection Method Based on Information Measures for Spectral Image Color Visualization
2011
International audience; We present a new method for the visualization of spectral images, based on a selection of three relevant spectral channels to build a Red-Green-Blue composite. Band selection is achieved by means of information measures at the first, second and third orders. Irrelevant channels are preliminarily removed by means of a center-surround entropy comparison. A visualization-oriented spectrum segmentation based on the use of color matching functions allows for computational ease and adjustment of the natural rendering. Results from the proposed method are presented and objectively compared to four other dimensionality reduction techniques in terms of naturalness and informa…
Source separation on hyperspectral cube applied to dermatology
2010
International audience; This paper proposes a method of quantification of the components underlying the human skin that are supposed to be responsible for the effective reflectance spectrum of the skin over the visible wavelength. The method is based on independent component analysis assuming that the epidermal melanin and the dermal haemoglobin absorbance spectra are independent of each other. The method extracts the source spectra that correspond to the ideal absorbance spectra of melanin and haemoglobin. The noisy melanin spectrum is fixed using a polynomial fit and the quantifications associated with it are reestimated. The results produce feasible quantifications of each source compone…
High resolution study of the six lowest doubly excited vibrational states of PH2D
2005
Abstract The five lowest doubly excited deformational vibrational bands ν 4 + ν 6 , 2 ν 6 , ν 3 + ν 4 , ν 3 + ν 6 , and 2 ν 3 of PH 2 D have been recorded for the first time using a Bruker 120 HR interferometer with a resolution 0.0033 cm −1 and analysed. Some transitions belonging to a very weak band 2 ν 4 have been also assigned. From the fit 24 and 86, respectively, diagonal and resonance interaction parameters were obtained which reproduce 1089 upper energy levels obtained from more than 4600 assigned transitions with the rms deviation of 0.00059 cm −1 .
Analysis of highly excited 'hot' bands in the SO2 molecule: ν2 + 3ν3 - ν2 and 2ν1 + ν2 + ν3 - ν2
2010
International audience; We set up a variational procedure of assignments of transitions and we applied it to the analysis very weak 'hot' bands, v(2) + 3v(3) - v(2) and 2v(1) + v(2) + v(3) - v(2), of the SO2 molecule. As the first step of the study, the 'cold' bands, 3v(3) and 2v(1) + v(3), are re-analysed and transitions belonging to those bands are assigned up to the values of quantum numbers J(max.) = 60, K-a(max.) = 19, and J(max.) = 69, K-a(max.) = 20 for the bands 3v(3) and 2v(1) + v(3), respectively. After 'cleaning' the experimental spectrum from transitions belonging to the 3v(3) and 2v(1) + v(3) bands, a variational procedure was used that allowed us to assign 230 and 115 transiti…
A note on Hilbert’s weak nullstellensatz
2015
In this article, through a suitable generalization of the well-known notion of spectrum of an element of an arbitrary normed algebra of Operator Theory, it will be possible to give another simple proof of the Hilbert’s Weak Nullstellensatz.
On Gelfand-Mazur Theorem
2015
From a suitable extension of the notion of spectrum drew from normed algebra theory, it will be possible, among other things, to provide some generalizations of the well-known Gelfand-Mazur theorem. In this brief research report, we wish to pursue one of these, as achieved in I,4.
The rapid atmospheric monitoring system of the Pierre Auger Observatory
2012
The Pierre Auger Observatory is a facility built to detect air showers produced by cosmic rays above 1017 eV. During clear nights with a low illuminated moon fraction, the UV fluorescence light produced by air showers is recorded by optical telescopes at the Observatory. To correct the observations for variations in atmospheric conditions, atmospheric monitoring is performed at regular intervals ranging from several minutes (for cloud identification) to several hours (for aerosol conditions) to several days (for vertical profiles of temperature, pressure, and humidity). In 2009, the monitoring program was upgraded to allow for additional targeted measurements of atmospheric conditions shor…
Bounds on the density of sources of ultra-high energy cosmic rays from the Pierre Auger Observatory
2013
We derive lower bounds on the density of sources of ultra-high energy cosmic rays from the lack of significant clustering in the arrival directions of the highest energy events detected at the Pierre Auger Observatory. The density of uniformly distributed sources of equal intrinsic intensity was found to be larger than similar to (0.06 – 5) x 10(-4) Mpc(-3) at 95% CL, depending on the magnitude of the magnetic defections. Similar bounds, in the range (0.2 – 7) x 10(-4) Mpc(-3), were obtained for sources following the local matter distribution.