2,885,557 research outputs found

    Intermodulated optogalvanic spectroscopy - a comparison with other high-resolution techniques

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    A comparison of intermodulated fluorescence spectroscopy, intermodulated optogalvanic spectroscopy, POLINEX (POLarization INtermodulated EXcitation) spectroscopy and polarization spectroscopy used in Doppler-free spectroscopy on hollow cathode discharges is made, mainly based on experiments performed on the 2p53s 3P2 - 2p53p 3P1 transition in Ne at λ=5882 Å and the 4d55s 5S2 - 4d55p 5P3 transition in Mo at λ=5506 Å. Some general aspects regarding the hollow cathode as a tool in high-resolution laser spectroscopy are also briefly discussed

    Inaccurate, Costly, and Inefficient: Evidence That America's Voter Registration System Needs an Upgrade

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    Outlines the cost of inaccurate or multiple registrations, registrations of the deceased, and unregistered eligible voters and plans to update lists via data comparison with other sources, proven data-matching techniques, and expanded online registration

    Transport methods and interactions for space radiations

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    A review of the program in space radiation protection at the Langley Research Center is given. The relevant Boltzmann equations are given with a discussion of approximation procedures for space applications. The interaction coefficients are related to solution of the many-body Schroedinger equation with nuclear and electromagnetic forces. Various solution techniques are discussed to obtain relevant interaction cross sections with extensive comparison with experiments. Solution techniques for the Boltzmann equations are discussed in detail. Transport computer code validation is discussed through analytical benchmarking, comparison with other codes, comparison with laboratory experiments and measurements in space. Applications to lunar and Mars missions are discussed

    Real-time reverse transcription polymerase chain reaction development for rapid detection of Tomato brown rugose fruit virus and comparison with other techniques

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    Background: Tomato brown rugose fruit virus (ToBRFV) is a highly infectious tobamovirus that causes severe disease in tomato (Solanum lycopersicum L.) crops. In Italy, the first ToBRFV outbreak occurred in 2018 in several provinces of the Sicily region. ToBRFV outbreak represents a serious threat for tomato crops in Italy and the Mediterranean Basin. Methods: Molecular and biological characterisation of the Sicilian ToBRFV ToB-SIC01/19 isolate was performed, and a sensitive and specific Real-time RT-PCR TaqMan minor groove binder probe method was developed to detect ToBRFV in infected plants and seeds. Moreover, four different sample preparation procedures (immunocapture, total RNA extraction, direct crude extract and leaf-disk crude extract) were evaluated. Results: The Sicilian isolate ToB-SIC01/19 (6,391 nt) showed a strong sequence identity with the isolates TBRFV-P12-3H and TBRFV-P12-3G from Germany, Tom1-Jo from Jordan and TBRFV-IL from Israel. The ToB-SIC01/19 isolate was successfully transmitted by mechanical inoculations in S. lycopersicum L. and Capsicum annuum L., but no transmission occurred in S. melongena L. The developed real-time RT-PCR, based on the use of a primer set designed on conserved sequences in the open reading frames3, enabled a reliable quantitative detection. This method allowed clear discrimination of ToBRFV from other viruses belonging to the genus Tobamovirus, minimising false-negative results. Using immunocapture and total RNA extraction procedures, the real-time RT-PCR and end-point RT-PCR gave the same comparable results. Using direct crude extracts and leaf-disk crude extracts, the end-point RT-PCR was unable to provide a reliable result. This developed highly specific and sensitive real-time RT-PCR assay will be a particularly valuable tool for early ToBRFV diagnosis, optimising procedures in terms of costs and time

    Principles of ESCA and application to metal corrosion, coating and lubrication

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    The principles of ESCA (electron spectroscopy for chemical analysis) were described by comparison with other spectroscopic techniques. The advantages and disadvantages of ESCA as compared to other surface sensitive analytical techniques were evaluated. The use of ESCA was illustrated by actual applications to oxidation of steel and Rene 41, the chemistry of lubricant additives on steel, and the composition of sputter deposited hard coatings. A bibliography of material that was useful for further study of ESCA was presented and commented upon

    An exact solution for two dimensional wetting with a corrugated wall

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    An exact solution of a two dimensional RSOS model of wetting at a corrugated (periodic) wall is found using transfer matrix techniques. In contrast to mean-field analysis of the same problem the wetting transition remains second-order and occurs at a lower temperature than that of the planar system. Comparison with numerical studies and other analytical approaches is made.Comment: 11 pages LaTex with 1 eps figure. To appear in J.Phys.

    Digital Demodulator for BFSK waveform based upon Correlator and Differentiator Systems

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    The present article relates in general to digital demodulation of Binary Frequency Shift Keying (BFSK waveform) . New processing methods for demodulating the BFSK-signals are proposed here. Based on Sampler Correlator, the hardware consumption for the proposed techniques is reduced in comparison with other reported. Theoretical details concerning limits of applicability are also given by closed-form expressions. Simulation experiments are illustrated to validate the overall performance
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