2,826 research outputs found
Contribución al conocimiento litoestratigráfico del Cretácico de la zona central de la región asturiana
Se describen, de muro a techo en la zona media de la serie cretácica asturiana, tres unidades litoestratigráficas: de margas nodulosas grises, calcáreo-detrítica y detrítica micácea. Estas unidades resultan litológicamente características y fácilmente reconocibles en el campo. En consecuencia, se proponen como buenos niveles guía en una extensión que abarca desde el W de Oviedo hasta el meridiano de Ceceda
Nota sobre las características estructurales de la zona de "Cueto Negro" (Cordillera Cantábrica)
Se citan algunos datos estructurales respecto a la zona comprendida entre los puertos Pajares y La Cubilla (Cordillera Cantábrica). Se destaca la presencia de una ventana tectónica, en la zona de Cueto negro, relacionada con la unidad cabalgante de Bodón, ampliamente replegada. Estos elementos se integran dentro del haz de estructuras que caracterizan el "arco medio" de la Rodilla Astúrica (Cordillera Cantábrica, España)
The utilization of an ultrasound-guided 8-gauge vacuum-assisted breast biopsy system as an innovative approach to accomplishing complete eradication of multiple bilateral breast fibroadenomas
<p>Abstract</p> <p>Background</p> <p>Ultrasound-guided vacuum-assisted breast biopsy technology is extremely useful for diagnostic biopsy of suspicious breast lesions and for attempted complete excision of appropriately selected presumed benign breast lesions.</p> <p>Case presentation</p> <p>A female patient presented with 16 breast lesions (eight within each breast), documented on ultrasound and all presumed to be fibroadenomas. Over a ten and one-half month period of time, 14 of these 16 breast lesions were removed under ultrasound guidance during a total of 11 separate 8-gauge Mammotome<sup>® </sup>excision procedures performed during seven separate sessions. Additionally, two of these 16 breast lesions were removed by open surgical excision. A histopathologic diagnosis of fibroadenoma and/or fibroadenomatous changes was confirmed at all lesion excision sites. Interval follow-up ultrasound imaging revealed no evidence of a residual lesion at the site of any of the 16 original breast lesions.</p> <p>Conclusion</p> <p>This report describes an innovative approach of utilizing ultrasound-guided 8-gauge vacuum-assisted breast biopsy technology for assisting in achieving complete eradication of multiple bilateral fibroadenomas in a patient who presented with 16 documented breast lesions. As such, this innovative approach is highly recommended in similar appropriately selected patients.</p
Estudi sobre l’aplicació del Pla del Verd i de la Biodiversitat als Projectes : Rehabilitació integral (PRI) de Parcs i Jardins de Barcelona del 2016 al 2019
El present document respon a l’encàrrec que Parcs i Jardins, Institut Municipal ha realitzat a Irati Proyectos, S.L., per a un estudi sobre l’Aplicació del Pla del Verd i la Biodiversitat en els Projectes de Rehabilitació Integral de Parcs i Jardins per el període 2016-2019. L’objecte de l’estudi que aquí es presenta és l’avaluació de les possibilitats de canvi i millora cap a un model més naturalitzat de gestió de 20 emplaçaments proposats per la Direcció d’Espais Verds i Biodiversitat (DEVB), i inclou la valoració econòmica prèvia de les propostes d’actuació, la proposta de manteniment diferenciat a dur a terme per part dels conservadors, així com els indicadors de seguiment recomanables per a comprovar el nivell de biodiversitat en cada espai intervingut
Stellar populations of bulges at low redshift
This chapter summarizes our current understanding of the stellar population
properties of bulges and outlines important future research directions.Comment: Review article to appear in "Galactic Bulges", Editors: Laurikainen
E., Peletier R., Gadotti D., Springer Publishing. 34 pages, 12 figure
A mathematical and computational review of Hartree-Fock SCF methods in Quantum Chemistry
We present here a review of the fundamental topics of Hartree-Fock theory in
Quantum Chemistry. From the molecular Hamiltonian, using and discussing the
Born-Oppenheimer approximation, we arrive to the Hartree and Hartree-Fock
equations for the electronic problem. Special emphasis is placed in the most
relevant mathematical aspects of the theoretical derivation of the final
equations, as well as in the results regarding the existence and uniqueness of
their solutions. All Hartree-Fock versions with different spin restrictions are
systematically extracted from the general case, thus providing a unifying
framework. Then, the discretization of the one-electron orbitals space is
reviewed and the Roothaan-Hall formalism introduced. This leads to a exposition
of the basic underlying concepts related to the construction and selection of
Gaussian basis sets, focusing in algorithmic efficiency issues. Finally, we
close the review with a section in which the most relevant modern developments
(specially those related to the design of linear-scaling methods) are commented
and linked to the issues discussed. The whole work is intentionally
introductory and rather self-contained, so that it may be useful for non
experts that aim to use quantum chemical methods in interdisciplinary
applications. Moreover, much material that is found scattered in the literature
has been put together here to facilitate comprehension and to serve as a handy
reference.Comment: 64 pages, 3 figures, tMPH2e.cls style file, doublesp, mathbbol and
subeqn package
Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV
The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8 TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum
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