Establishment of the spectra of kinetic turbulence

An analysis of kinetic equations describing the establishment of Langmuir turbulence spectra is presented. Secondary turbulence occurs where stationary distribution consists of many peaks. The position of peaks is established and their amplitudes complete undamped oscillations. It is pointed out that establishing spectra can occur only during adiabatic inclusion of pumping. It is significant here that the adiabiatic condition is more rigid than the ordinary by several hundred times

Detection of Trace Amounts of Toxic Metals in Environmental Samples by Laser-excited Atomic Fluorescence Spectrometry

Results for the direct determination of trace amounts of Pb and Cd in Antarctic and Greenland ancient ice and recent snow by laser-excited atomic fluorescence spectrometry (LEAFS) are presented. The whole procedure starting from field sampling, mechanical decontamination of the samples in an ultra-clean laboratory and final analysis of the decontaminated samples is described. The measured concentrations varied in the ranges 0.1–3 pg ml^(–1) for Cd and 0.3–30 pg ml^(–1) for Pb. The results for direct analysis by LEAFS agree favourable with those obtained by isotope dilution mass spectrometry and electrothermal atomic absorption spectrometry, which require time-consuming pre-treatment and pre-concentration stages

Cost of human capital estimation and management in medical organization

© Medwell Journals, 2016.The purpose of this research is the analysis and improvement of technology of human capital cost management for maintaining efficient personnel policy in a modern organization. The study offers researchers method of assessment and management of investments in human capital. This method involves structure of cost behavior during formation and development of human capital, change history of investment risks on each stage of business career, modeling of volume of investments on various degrees of their riskiness, mathematical analysis and forecasting profitability of investments in human capital, development of recommendations on human capital cost management. Furthermore, it determines investment appeal of human capital development. The real method is assayed on the materials of a project on human capital development in "KORL" JSC. To maintain human capital cost management we offer systematic monitoring of its current value and change on the basis of the offered optimizing models, following the investment approach for personnel decision making, personalization in accounting the investments in human capital and its profitability

УСТРАНЕНИЕ МАТРИЧНЫХ НЕСПЕКТРАЛЬНЫХ ПОМЕХ ПРИ ЭЛЕМЕНТНОМ АНАЛИЗЕ БИОЛОГИЧЕСКИХ ЖИДКОСТЕЙ НА КВАДРУПОЛЬНОМ МАСС-СПЕКТРОМЕТРЕ С ИНДУКТИВНО СВЯЗАННОЙ ПЛАЗМОЙ

The comparison of two most frequently used sample preparation techniques of biological fluids before mass-spectrometric determination of Mn, Co, Cu, Zn, As, Se, Cd and Pb – simple (direct) dilution and acid mineralization – was carried out using quadrupole mass-spectrometer. The significant underestimation of the results in comparison with diluted samples for the elements with relatively high ionization potentials was found while analyzing digested biofluids. The key role of acid effect was proven to be the reason of such discrepancy. Moreover, the contributions of saline and organic matrix non-spectral interferences in both diluted and mineralized samples – to the underestimation of the obtained results were evaluated. It was shown that the selection of the appropriate internal standard based on matching of the standard’s and analyte’s ionization potentials not the masses can eliminate the described interferences without matrix-matched calibration. Furthermore, the working mass-spectrometer conditions that allow to use any single internal standard (irrespective of it’s mass and/or ionization potential) were found. Based on the experimental data the approach of element determination in biological fluids with the use of quadrupole ICP-MS was suggested. It provides the possibility of simultaneous determination of various elements without changing the work mass-spectrometer conditions. The satisfactory agreement between the found and certified concentration values for all the elements analyzed in the diluted and mineralized samples of whole blood and urine reference materials proved the applicability of the approach.Keywords: biological fluids, elemental analysis, inductively coupled mass-spectrometry, matrix non-spectral interferences, internal standards(Russian)DOI: http://dx.doi.org/10.15826/analitika.2014.18.2.003 K.B. Osipov1, I. F. Seregina1, M. A. Bol`shov1,2 1Lomonosov Moscow State University, Moscow, Russian Federation2Institute for Spectroscopy RAS, Troitsk, Moscow, Russian FederationНа примере определения Mn, Co, Cu, Zn, As, Se, Cd и Pb в цельной крови и моче с использованием квадрупольного масс-спектрометра с индуктивно связанной плазмой Agilent 7500c произведено сравнение двух наиболее часто применяемых способов пробоподготовки биологических жидкостей: прямого разбавления и кислотного разложения. Обнаружено значительное занижение результатов анализа в минерализованных пробах (по сравнению с результатами анализа в разбавленных образцах) для элементов с относительно высоким первым потенциалом ионизации. Показано, что основной причиной такого расхождения является различие проб и градуировочных растворов по матричному составу: высокая кислотность проб после разложения. Дополнительно оценены вклады солевого и органического состава матрицы в занижение получаемых результатов как в разложенных, так и разбавленных пробах. Установлено, что для устранения подобных помех при использовании масс-спектрометра данной комплектации без подбора матрицы градуировочных растворов ключевым является выбор элемента внутреннего стандарта, который осуществляется, исходя из близости его первого потенциала ионизации к соответствующему потенциалу ионизации определяемого элемента. Найден режим работы прибора, который позволяет использовать один любой внутренний стандарт независимо от его природы – атомной массы и/или потенциала ионизации. На основании проведенных исследований предложена схема анализа указанных образцов с использованием квадрупольного масс-спектрометра с индуктивно связанной плазмой, обеспечивающая одновременное определение различных элементов без оптимизации рабочих параметров для каждого аналита. Удовлетворительное совпадение между найденными и аттестованными значениями концентраций всех элементов, определяемых в разбавленных и разложенных образцах сравнения цельной крови и мочи, подтверждает применимость подхода.Ключевые слова: биологические жидкости, элементный анализ, масс-спектрометрия с индуктивно связанной плазмой, матричные неспектральные помехи, внутренний стандарт.DOI: http://dx.doi.org/10.15826/analitika.2014.18.2.003

Stochastic Pulse Switching in a Degenerate Resonant Optical Medium

Using the idealized integrable Maxwell-Bloch model, we describe random optical-pulse polarization switching along an active optical medium in the Lambda-configuration with disordered occupation numbers of its lower energy sub-level pair. The description combines complete integrability and stochastic dynamics. For the single-soliton pulse, we derive the statistics of the electric-field polarization ellipse at a given point along the medium in closed form. If the average initial population difference of the two lower sub-levels vanishes, we show that the pulse polarization will switch intermittently between the two circular polarizations as it travels along the medium. If this difference does not vanish, the pulse will eventually forever remain in the circular polarization determined by which sub-level is more occupied on average. We also derive the exact expressions for the statistics of the polarization-switching dynamics, such as the probability distribution of the distance between two consecutive switches and the percentage of the distance along the medium the pulse spends in the elliptical polarization of a given orientation in the case of vanishing average initial population difference. We find that the latter distribution is given in terms of the well-known arcsine law

Evidence for the exclusive decay Bc+- to J/psi pi+- and measurement of the mass of the Bc meson

We report first evidence for a fully reconstructed decay mode of the B_c^{\pm} meson in the channel B_c^{\pm} \to J/psi \pi^{\pm}, with J/psi \to mu^+mu^-. The analysis is based on an integrated luminosity of 360 pb$^{-1} in p\bar{p} collisions at 1.96 TeV center of mass energy collected by the Collider Detector at Fermilab. We observe 14.6 \pm 4.6 signal events with a background of 7.1 \pm 0.9 events, and a fit to the J/psi pi^{\pm} mass spectrum yields a B_c^{\pm} mass of 6285.7 \pm 5.3(stat) \pm 1.2(syst) MeV/c^2. The probability of a peak of this magnitude occurring by random fluctuation in the search region is estimated as 0.012%.Comment: 7 pages, 3 figures. Version 3, accepted by PR

Search for the Higgs boson in events with missing transverse energy and b quark jets produced in proton-antiproton collisions at s**(1/2)=1.96 TeV

We search for the standard model Higgs boson produced in association with an electroweak vector boson in events with no identified charged leptons, large imbalance in transverse momentum, and two jets where at least one contains a secondary vertex consistent with the decay of b hadrons. We use ~1 fb-1 integrated luminosity of proton-antiproton collisions at s**(1/2)=1.96 TeV recorded by the CDF II experiment at the Tevatron. We find 268 (16) single (double) b-tagged candidate events, where 248 +/- 43 (14.4 +/- 2.7) are expected from standard model background processes. We place 95% confidence level upper limits on the Higgs boson production cross section for several Higgs boson masses ranging from 110 GeV/c2 to 140 GeV/c2. For a mass of 115 GeV/c2 the observed (expected) limit is 20.4 (14.2) times the standard model prediction.Comment: 8 pages, 2 figures, submitted to Phys. Rev. Let

Inclusive Search for Anomalous Production of High-pT Like-Sign Lepton Pairs in Proton-Antiproton Collisions at sqrt{s}=1.8 TeV

We report on a search for anomalous production of events with at least two charged, isolated, like-sign leptons with pT > 11 GeV/c using a 107 pb^-1 sample of 1.8 TeV ppbar collisions collected by the CDF detector. We define a signal region containing low background from Standard Model processes. To avoid bias, we fix the final cuts before examining the event yield in the signal region using control regions to test the Monte Carlo predictions. We observe no events in the signal region, consistent with an expectation of 0.63^(+0.84)_(-0.07) events. We present 95% confidence level limits on new physics processes in both a signature-based context as well as within a representative minimal supergravity (tanbeta = 3) model.Comment: 15 pages, 4 figures. Minor textual changes, cosmetic improvements to figures and updated and expanded reference

Measurement of the Helicity Fractions of W Bosons from Top Quark Decays Using Fully Reconstructed top-antitop Events with CDF II

We present a measurement of the fractions F_0 and F_+ of longitudinally polarized and right-handed W bosons in top quark decays using data collected with the CDF II detector. The data set used in the analysis corresponds to an integrated luminosity of approximately 318 pb -1. We select ttbar candidate events with one lepton, at least four jets, and missing transverse energy. Our helicity measurement uses the decay angle theta*, which is defined as the angle between the momentum of the charged lepton in the W boson rest frame and the W momentum in the top quark rest frame. The cos(theta*) distribution in the data is determined by full kinematic reconstruction of the ttbar candidates. We find F_0 = 0.85 +0.15 -0.22 (stat) +- 0.06 (syst) and F_+ = 0.05 +0.11 -0.05 (stat) +- 0.03 (syst), which is consistent with the standard model prediction. We set an upper limit on the fraction of right-handed W bosons of F_+ < 0.26 at the 95% confidence level.Comment: 11 pages, 2 figures, submitted to Phys. Rev.