2,213 research outputs found

    Conodont Zonation of the Early Upper Devonian in Eastern Iowa

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    The type section of the Sweetland Creek Shale in Muscatine County has yielded a sequence of five distinct conodont faunas which correspond almost exactly to a zonation of the Upper Devonian Frasnian Stage by Ziegler (1962 b) in the Rhineland. In addition, the nearby Campbell\u27s Run section has produced the lower three faunas. The Sweetland Creek is equivalent in part to the Independence Formation, and is regarded as representing the southeastern extension of that unit in its true stratigraphic position above the Cedar Valley Formation

    Application of pulse radiolysis to the study of proteins: chymotrypsin and trypsin

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    The one-electron reduction of chymotrypsin, trypsin, and their zymogens have been studied by pulse radiolysis. The optical spectra of the transient products from the two active enzymes display a pH-dependent band at 360 nm, associated with the histidine-electron adduct. The yield of the histidyl radical as a function of pH is consistent with a pK(a) less than 4.5, which suggests that the radical is located at the enzyme active site. The histidines of the proenzymes chymotrypsinogen and trypsinogen are unreactive towards the hydrated electron. We conclude that formation of the histidine-electron adduct at the serine protease active site is sensitive to the physical alterations which accompany protease activation

    Huyghens, Bohr, Riemann and Galois: Phase-Locking

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    Several mathematical views of phase-locking are developed. The classical Huyghens approach is generalized to include all harmonic and subharmonic resonances and is found to be connected to 1/f noise and prime number theory. Two types of quantum phase-locking operators are defined, one acting on the rational numbers, the other on the elements of a Galois field. In both cases we analyse in detail the phase properties and find them related respectively to the Riemann zeta function and to incomplete Gauss sums.Comment: 18 pages paper written in relation to the ICSSUR'05 conference held in Besancon, France to be published at a special issue of IJMP

    Entrepreneurship and Firm Formation Across Countries

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    The World Bank Group Entrepreneurship Survey measures entrepreneurial activity around the world. The database includes cross-country, time-series data on the number of total and newly registered businesses for 84 countries. This paper finds significant relationships between entrepreneurial activity and indicators of economic and financial development and growth, the quality of the legal and regulatory environment, and governance. The analysis shows the importance of electronic registration procedures to encourage greater business registration. These results can guide effective policymaking and deliver new capabilities for identifying the impact of reforms

    X-ray diffraction study of KTP (KTiOPO 4

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    Влияние параметров искрового плазменного спекания на структурно-фазовое состояние керамических композитов на основе MAX-фаз, полученных из прекерамической бумаги

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    Композитные материалы на основе MAX – фаз сочетают в себе особенности керамик и металлов. Данное сочетание позволяет использовать их в различных областях производства, таких как электроника. В данной работе изучается влияние параметров искрового плазменного спекания на структурно-фазовое состояние керамических композитов на основе MAX – фаз, полученных из прекерамической бумаги. В результате были получены данные об изменении фазового состава, микроструктуры, плотности и пористости композита при различных значениях давления и температур искрового плазменного спекания.Composite materials based on MAX - phases combine the features of ceramics and metals. This combination allows you to use them in various areas of production, such as electronics. In this work, we study the effect of spark plasma sintering parameters on the structural phase state of ceramic composites based on MAX phases obtained from preceramic paper. As a result, data were obtained on changes in the phase composition, microstructure, density and porosity of the composite at various values ??of pressure and spark plasma sintering temperatures

    Accurate laboratory rest frequencies of vibrationally excited CO up to varv=3varv = 3 and up to 2 THz

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    Astronomical observations of (sub)millimeter wavelength pure rotational emission lines of the second most abundant molecule in the Universe, CO, hold the promise of probing regions of high temperature and density in the innermost parts of circumstellar envelopes. The rotational spectrum of vibrationally excited CO up to \varv = 3 has been measured in the laboratory between 220 and 1940 GHz with relative accuracies up to 5.2×1095.2 \times 10^{-9}, corresponding to 5\sim 5 kHz near 1 THz. The rotational constant BB and the quartic distortion parameter DD have been determined with high accuracy and even the sextic distortion term HH was determined quite well for \varv = 1 while reasonable estimates of HH were obtained for \varv = 2 and 3. The present data set allows for the prediction of accurate rest frequencies of vibrationally excited CO well beyond 2 THz.Comment: Astron. Astrophys, accepted; 5 pages, 2 Figures, 2 Table

    Fintech, financial inclusion and income inequality: A quantile regression approach

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    Although theory suggests that financial market imperfections – mainly information asymmetries, market segmentation and transaction costs – prevent poor people from escaping poverty by limiting their access to formal financial services, new financial technologies (FinTech) are seen as key enablers of financial inclusion. Indeed, the UN 2030 Agenda for Sustainable Development (UN-2030-ASD) and the G20 High-Level Principles for Digital Financial Inclusion (G20-HLP-DFI) highlight the importance of harnessing the potential of FinTech to reduce financial exclusion and income inequality. This paper investigates the interrelationship between FinTech, financial inclusion and income inequality for a panel of 140 countries using the Global Findex waves of survey data for 2011, 2014 and 2017. We posit that FinTech affects inequality directly and indirectly through financial inclusion. We invoke quantile regression analysis to investigate whether such effects differ across countries with different levels of income inequality. We uncover new evidence that financial inclusion is a key channel through which FinTech reduces income inequality. We also find that while financial inclusion significantly reduces inequality at all quantiles of the inequality distribution, these effects are primarily associated with higher-income countries. Overall, our results support the aspirations of the UN-2030-ASD and G20-HLP-DFI
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