Conodont Zonation of the Early Upper Devonian in Eastern Iowa

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

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

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

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

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

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

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 $5.2 \times 10^{-9}$, corresponding to $\sim 5$ kHz near 1 THz. The rotational constant $B$ and the quartic distortion parameter $D$ have been determined with high accuracy and even the sextic distortion term $H$ was determined quite well for \varv = 1 while reasonable estimates of $H$ 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

Origin and pathogenesis of nodular lymphocyte–predominant Hodgkin lymphoma as revealed by global gene expression analysis

The pathogenesis of nodular lymphocyte–predominant Hodgkin lymphoma (NLPHL) and its relationship to other lymphomas are largely unknown. This is partly because of the technical challenge of analyzing its rare neoplastic lymphocytic and histiocytic (L&H) cells, which are dispersed in an abundant nonneoplastic cellular microenvironment. We performed a genome-wide expression study of microdissected L&H lymphoma cells in comparison to normal and other malignant B cells that indicated a relationship of L&H cells to and/or that they originate from germinal center B cells at the transition to memory B cells. L&H cells show a surprisingly high similarity to the tumor cells of T cell–rich B cell lymphoma and classical Hodgkin lymphoma, a partial loss of their B cell phenotype, and deregulation of many apoptosis regulators and putative oncogenes. Importantly, L&H cells are characterized by constitutive nuclear factor {kappa}B activity and aberrant extracellular signal-regulated kinase signaling. Thus, these findings shed new light on the nature of L&H cells, reveal several novel pathogenetic mechanisms in NLPHL, and may help in differential diagnosis and lead to novel therapeutic strategies