836 research outputs found

    Remote Sensing analysis of the meanders migration in the Mamorecillo River between 1985 and 2012, Bolivia

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    The morphology of a channel, in a space-time resolution, suffers with sedimentological processes of erosion, transport and deposition. Processes that are more accentuated in meandering channels. In the present work the objective is to analyze, identify and discuss the changes occurred in spatial and temporal sequence in the form of the meanders and river bed of a section of the Mamorecillo River between the provinces of Cochabamba and Santa Cruz - Bolivia. Characterized by being an extensively meandering river - characteristic of the river basin in which it is inserted, the Amazon Basin, the present study, through remote sensing resources, seeks to discuss and correlate the changes occurred in the channel in a period of twenty-seven years (1985-2012). As well as understanding the processes of migration of the meanders that this section of the Mamorecillo River suffered through the sedimentological processes of erosion and deposition and consequently understand the processes in the Amazon basin. For the accomplishment of the work, the studied area was delimited and allied with geoprocessing tools such as software and aerial images, the main geomorphological features were identified and their changes discussed during the studied period. In this work, we intend to correlate and verify the inter-dependence (referring to the sedimentological and / or hydrological contribution) that exists between the Mamorecillo River and the Chimoreacute; and Ichilo rivers

    Near-infrared observations of galaxies in Pisces-Perseus: I. H-band surface photometry of 174 spirals

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    We present near-infrared, H-band (1.65 um), surface photometry of 174 spiral galaxies in the area of the Pisces-Perseus supercluster. The images, acquired with the ARNICA camera mounted on various telescopes, are used to derive radial profiles of surface brightness, ellipticities, and position angles, together with global parameters such as H-band magnitudes and diameters. The mean relation between H-band isophotal diameter D_{21.5} and the B-band D_{25} implies a B-H color of the outer disk bluer than 3.5; moreover, D_{21.5}/D_{25} depends on (global) color and absolute luminosity. The correlations among the various photometric parameters suggest a ratio between isophotal radius D_{21.5}/2 and disk scale length of about 3.5 and a mean disk central brightness of 17.5 H-mag arcsec^{-2}. We confirm the trend of the concentration index C_{31} with absolute luminosity and, to a lesser degree, with morphological type. We also assess the influence of non-axisymmetric structures on the radial profiles and on the derived parameters.Comment: 10 pages, 11 postscript figures (one table and one figure are available only at the CDS); to be published on A&A

    Magnetic resonance imaging landmarks for preoperative localization of inferior medial genicular artery: a proof of concept analysis

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    The joint line is a useful landmark to identify IMGAcourse during knee surgery. The IMGA course is closerto the joint line and to the border of the medial tibialplateau in females than in males. Although the interindi-vidual variability these results should be taken into ac-count when performing all surgical procedures involvingthe medial aspect of the knee. Similar interindividualdistances were observed between IMGA and semimem-branosus tendon insertion regardless of gender. How-ever, the proximity to this tendon should be consideredespecially during specific cases of ligamentous balancingin TKA procedure

    VIP: An Experiment to Search for a Violation of the Pauli Exclusion Principle

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    The Pauli Exclusion Principle is a basic principle of Quantum Mechanics, and its validity has never been seriously challenged. However, given its fundamental standing, it is very important to check it as thoroughly as possible. Here we describe the VIP (VIolation of the Pauli exclusion principle) experiment, an improved version of the Ramberg and Snow experiment (E. Ramberg and G. Snow, {\it Phys. Lett. B} {\bf 238}, 438 (1990)); VIP has just completed the installation at the Gran Sasso underground laboratory, and aims to test the Pauli Exclusion Principle for electrons with unprecedented accuracy, down to β2/210301031\beta^2/2 \approx 10^{-30} - 10^{-31}. We report preliminary experimental results and briefly discuss some of the implications of a possible violation.Comment: Plenary talk presented by E. Milotti at Meson 2006, Cracow, 9-13 June 200

    New experimental limit on the Pauli Exclusion Principle violation by electrons

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    The Pauli Exclusion Principle (PEP) is one of the basic principles of modern physics and, even if there are no compelling reasons to doubt its validity, it is still debated today because an intuitive, elementary explanation is still missing, and because of its unique stand among the basic symmetries of physics. The present paper reports a new limit on the probability that PEP is violated by electrons, in a search for a shifted Kα_\alpha line in copper: the presence of this line in the soft X-ray copper fluorescence would signal a transition to a ground state already occupied by 2 electrons. The obtained value, 1/2β24.5×1028{1/2} \beta^{2} \leq 4.5\times 10^{-28}, improves the existing limit by almost two orders of magnitude.Comment: submitted to Phys. Lett.

    Identificação e resistência a antibióticos de gêneros bacterianos presentes em surubins criados em tanques-rede.

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    O surubim é uma espécie apreciada pelo mercado consumidor, entretanto, seu cultivo intensivo em tanques-rede pode trazer problemas de sanidade devido ao estresse dos peixes, caso não sejam utilizadas boas práticas de manejo. Neste trabalho, objetivou-se identificar e verificar a resistência aos antibióticos de gêneros bacterianos isolados de Pseudoplatystoma sp. criados em tanques-rede de baixo volume

    New experimental limit on Pauli Exclusion Principle violation by electrons (the VIP experiment)

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    The Pauli Exclusion Principle is one of the basic principles of modern physics and is at the very basis of our understanding of matter: thus it is fundamental importance to test the limits of its validity. Here we present the VIP (Violation of the Pauli Exclusion Principle) experiment, where we search for anomalous X-rays emitted by copper atoms in a conductor: any detection of these anomalous X-rays would mark a Pauli-forbidden transition. ] VIP is currently taking data at the Gran Sasso underground laboratories, and its scientific goal is to improve by at least four orders of magnitude the previous limit on the probability of Pauli violating transitions, bringing it into the 10**-29 - 10**-30 region. First experimental results, together with future plans, are presented.Comment: To appear in proceedings of the XLVI International Winter Meeting on Nuclear Physics, Bormio, Italy, January 20-26, 200

    The VIP Experiment

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    The Pauli Exclusion Principle (PEP) is a basic principle of Quantum Mechanics, and its validity has never been seriously challenged. However, given its importance, it is very important to check it as thoroughly as possible. Here we describe the VIP (Violation of PEP) experiment, an improved version of the Ramberg and Snow experiment (Ramberg and Snow, Phys. Lett. B238 (1990) 438); VIP shall be performed at the Gran Sasso underground laboratories, and aims to test the Pauli Exclusion Principle for electrons with unprecedented accuracy, down to β221030\frac{\beta^2}{2} \sim 10^{-30}Comment: 7 pages, 5 figures, PDF only, presented by Edoardo Milotti to the conference "Quantum Theory: reconsideration of foundations-3", Vaxjo (Sweden), June, 6-11 200
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