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Summary  

To verify the universal validity of the ``two-sided'' monotonicity condition introduced in [4], we will apply it to include more classical examples. The present paper selects the L p convergence case for this purpose. Furthermore, Theorem 3 shows that our improvements are not trivial.

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Abstract

By employing new ideas and techniques, we will refigure out the whole frame of L 1-approximation. First, except generalizing the coefficients from monotonicity to a wider condition, Logarithm Rest Bounded Variation condition, we will also drop the prior requirement fL 2π but directly consider the sine or cosine series. Secondly, to achieve nontrivial generalizations in complex spaces, we use a one-sided condition with some kind of balance conditions. In addition, a conjecture raised in [9] is disproved in Section 3.

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Abstract  

An international intercomparison exercise was conducted by the IAEA in 1994 on the edible fractions of biological samples collected in Mururoa. This article presents the results of additional measurements made on the inedible parts of marine samples, i.e., the gonads, viscera and livers of fish (groupers) and the hepatopancreas or viscera of mollusks (giant clams and turbos). The spread of data as a function of sampling locations has been investigated, while the concentration factors for several long-lived radionuclides have been determined and discussed. Plutonium-239/240 concentration data for giant clam flesh and hepatopancreas appear to be very close (approximately 0.6 Bq/kg wet weight), whereas60Co concentrations are 100 times less in flesh (3 Bq/kg wet weight) than in hepatopancreas. As regards groupers,239/240Pu and60Co concentrations in flesh are very low and close to the detection limit. These concentration values are 100 to 500 times lower than those recorded in livers. As for turbos, plutonium and60Co concentrations in viscera are 5 to 10 times higher than in soft parts. Based on these data, it becomes possible to determine which fractions of marine samples should be analyzed first in order to detect minute traces of60Co,137Cs and plutonium in Polynesia.

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Abstract

The bacterial pathogen Campylobacter jejuni is the leading cause of foodborne gastroenteritis in the developed world, with the organism being transmitted by ingestion of contaminated and undercooked poultry. Exposure to acid is an inevitable stressor for C. jejuni during gastric passage, yet the effect of low pH on C. jejuni virulence is still poorly understood. Here, we investigate the effect of acid-shock on C. jejuni viability, gene expression and host-cell invasion. C. jejuni strain NCTC 11168 survived acid exposure at pH 3.5 and above for up to 30 min without a drop in viability, and this exposure induced the expression of flagellar genes transcribed from σ54-dependent promoters. Furthermore, acid-shock resulted in increased C. jejuni invasion of m-ICcl2 mouse small intestine crypt cells grown on transwells, but not when the cells were grown on flat-bottomed wells. This suggests that C. jejuni might be invading intestinal epithelial cells at the basolateral side, possibly after paracellular passage. We hypothesize that acid-shock prior to intestinal entry may serve as a signal that primes C. jejuni to express its virulence gene repertoire including flagellar motility genes, but this requires further study in the context of an appropriate colonization or disease model.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: P. Povinec, M. Pham, J. Sanchez-Cabeza, G. Barci-Funel, R. Bojanowski, T. Boshkova, W. Burnett, F. Carvalho, B. Chapeyron, I. Cunha, H. Dahlgaard, N. Galabov, L. Fifield, J. Gastaud, J. Geering, I. Gomez, N. Green, T. Hamilton, F. Ibanez, M. Ibn Majah, M. John, G. Kanisch, T. Kenna, M. Kloster, M. Korun, L. Liong Wee Kwong, J. La Rosa, S. Lee, I. Levy-Palomo, M. Malatova, Y. Maruo, P. Mitchell, I. Murciano, R. Nelson, A. Nouredine, J. Oh, B. Oregioni, G. Le Petit, H. Pettersson, A. Reineking, P. Smedley, A. Suckow, T. van der Struijs, P. Voors, K. Yoshimizu, and E. Wyse

Abstract  

A reference material designed for the determination of anthropogenic and natural radionuclides in sediment, IAEA-384 (Fangataufa Lagoon sediment), is described and the results of certification are presented. The material has been certified for 8 radionuclides (40K, 60Co, 155Eu, 230Th, 238U, 238Pu, 239+240Pu and 241Am). Information values are given for 12 radionuclides (90Sr, 137Cs, 210Pb (210Po), 226Ra, 228Ra, 232Th, 234U, 235U, 239Pu, 240Pu and 241Pu). Less reported radionuclides include 228Th, 236U, 239Np and 242Pu. The reference material may be used for quality management of radioanalytical laboratories engaged in the analysis of radionuclides in the environment, as well as for the development and validation of analytical methods and for training purposes. The material is available from IAEA in 100 g units.

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