3,019 research outputs found
Exotic looped trajectories via quantum marking
We provide an analytical and theoretical study of exotic looped trajectories
(ELTs) in a double-slit interferometer with quantum marking. We use an excited
Rydberg-like atom and which-way detectors such as superconducting cavities,
just as in the Scully-Englert-Walther interferometer. We indicate appropriate
conditions on the atomic beam or superconducting cavities so that we determine
an interference pattern and fringe visibility exclusive from the ELTs. We
quantitatively describe our results for Rubidium atoms and propose this
framework as an alternative scheme to the double-slit experiment modified to
interfere only these exotic trajectories.Comment: 10 pages, 5 figure
Ovarian abscess with spontaneous vaginal drainage
The occurrence of a rare ovarian abscess, spontaneously drained through the vagina after an abdominal hysterectomy is described.The treatment was an oophorectomy.The various forms of primary ovarian abscess are discussed in connection with these observations. This case illustrates the need for adequate manipulation of the gonad during pelvic surgery in order to avoid parenchymal contamination and the subsequent formation of such abscesses.Descreve-se caso raro de abscesso ovariano, como complicação de histerectomia abdominal, e que drenou espontaneamente pela vagina. O tratamento realizado foi ooforectomia. Discute-se as várias formas de abscesso primário do ovário sendo que a pós operatória parece ser a mais comum. É necessário uma manipulação adequada da gônada em cirurgias pélvicas para se evitar a contaminação do estroma, o que propicia a formação do abscesso ovariano.1596159
Identification of 491 proteins in the tear fluid proteome reveals a large number of proteases and protease inhibitors
BACKGROUND: The tear film is a thin layer of fluid that covers the ocular surface and is involved in lubrication and protection of the eye. Little is known about the protein composition of tear fluid but its deregulation is associated with disease states, such as diabetic dry eyes. This makes this body fluid an interesting candidate for in-depth proteomic analysis. RESULTS: In this study, we employ state-of-the-art mass spectrometric identification, using both a hybrid linear ion trap-Fourier transform (LTQ-FT) and a linear ion trap-Orbitrap (LTQ-Orbitrap) mass spectrometer, and high confidence identification by two consecutive stages of peptide fragmentation (MS/MS/MS or MS(3)), to characterize the protein content of the tear fluid. Low microliter amounts of tear fluid samples were either pre-fractionated with one-dimensional SDS-PAGE and digested in situ with trypsin, or digested in solution. Five times more proteins were detected after gel electrophoresis compared to in solution digestion (320 versus 63 proteins). Ontology classification revealed that 64 of the identified proteins are proteases or protease inhibitors. Of these, only 24 have previously been described as components of the tear fluid. We also identified 18 anti-oxidant enzymes, which protect the eye from harmful consequences of its exposure to oxygen. Only two proteins with this activity have been previously described in the literature. CONCLUSION: Interplay between proteases and protease inhibitors, and between oxidative reactions, is an important feature of the ocular environment. Identification of a large set of proteins participating in these reactions may allow discovery of molecular markers of disease conditions of the eye
Acceptance of fluorescence detectors and its implication in energy spectrum inference at the highest energies
Along the years HiRes and AGASA experiments have explored the fluorescence
and the ground array experimental techniques to measure extensive air showers,
being both essential to investigate the ultra-high energy cosmic rays. However,
such Collaborations have published contradictory energy spectra for energies
above the GZK cut-off. In this article, we investigate the acceptance of
fluorescence telescopes to different primary particles at the highest energies.
Using CORSIKA and CONEX shower simulations without and with the new
pre-showering scheme, which allows photons to interact in the Earth magnetic
field, we estimate the aperture of the HiRes-I telescope for gammas, iron
nuclei and protons primaries as a function of the number of simulated events
and primary energy. We also investigate the possibility that systematic
differences in shower development for hadrons and gammas could mask or distort
vital features of the cosmic ray energy spectrum at energies above the
photo-pion production threshold. The impact of these effects on the true
acceptance of a fluorescence detector is analyzed in the context of top-down
production models
Comparison of membrane proteins of Mycobacterium tuberculosis H37Rv and H37Ra strains
Background: The potential causes for variation in virulence between distinct M. tuberculosis strains are still not fully known. However, differences in protein expression are probably an important factor. In this study we used a labelfree quantitative proteomic approach to estimate differences in protein abundance between two closely related M. tuberculosis strains; the virulent H37Rv strain and its attenuated counterpart H37Ra. Results: We were able to identify more than 1700 proteins from both strains. As expected, the majority of the identified proteins had similar relative abundance in the two strains. However, 29 membrane-associated proteins were observed with a 5 or more fold difference in their relative abundance in one strain compared to the other. Of note, 19 membrane- and lipo-proteins had higher abundance in H37Rv, while another 10 proteins had a higher abundance in H37Ra. Interestingly, the possible protein-export membrane protein SecF (Rv2586c), and three ABCtransporter proteins (Rv0933, Rv1273c and Rv1819c) were among the more abundant proteins in M. tuberculosis H37Rv. Conclusion: Our data suggests that the bacterial secretion system and the transmembrane transport system may be important determinants of the ability of distinct M. tuberculosis strains to cause disease
Width/length–weight relationships and condition factor of seven decapod crustaceans in a Brazilian tropical estuary
The analysis of body relationships and condition factors are useful tools in studies of marine populations, and they have been widely used in fishery research and management. In this study, width–weight (WWR) and length–weight (LWR) relationships and Fulton's condition factors were analyzed for six commercially important decapod crustacean species from the Paraguaçu River estuary (Todos os Santos Bay), eastern Brazil, namely Callinectes danae, C. exasperatus, C. marginatus, C. ornatus, Goniopsis cruentata and Ucides cordatus, and one non-indigenous species, Charybdis helleri. In total 5,704 individuals were measured and weighed during five years (2012–2017). The three allometric growth types for the crustacean species were observed, being most frequently the negative allometric growth. The analysis of covariance (ANCOVA) revealed significant differences between the sexes and climatic seasons in WWR/LWRs for the four species of the genus Callinectes, C. helleri, G. cruentata and U. cordatus, except for females and males of C. danae in WWR. The means for condition factor were generally higher for females than for males during the dry period, and in general, indicating good conditions for crustacean species. This study provided morpho-biometric parameters information will contribute stock management of traditional artisanal fisheries, and enable future comparative studies of populations of the same species.9 página
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