890 resultados para Beck, Aaron T


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An experimental overview of reactions induced by the stable, but weakly-bound nuclei (6)Li, (7)Li and (9)Be, and by the exotic, halo nuclei (6)He, (8)B, (11)Be and (17)F on medium-mass targets, such as (58)Ni, (59)Co or (64)Zn, is presented. Existing data on elastic scattering, total reaction cross sections, fusion processes, breakup and transfer channels are discussed in the framework of a CDCC approach taking into account the breakup degree of freedom.

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The reactions induced by the weakly bound (6)Li projectile interacting with the intermediate mass target (59)Co were investigated. Light charged particles singles and alpha-d coincidence measurements were performed at the near barrier energies E(lab) = 17.4, 21.5, 25.5 and 29.6 MeV. The main contributions of the different competing mechanisms are discussed. A statistical model analysis. Continuum-Discretized Coupled-Channels (CDCC) calculations and two-body kinematics were used as tools to provide information to disentangle the main components of these mechanisms. A significant contribution of the direct breakup was observed through the difference between the experimental sequential breakup cross section and the CDCC prediction for the non-capture breakup cross section. (C) 2009 Elsevier B.V. All rights reserved.

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Herein, we report a new approach of an FePt nanoparticle formation mechanism studying the evolution of particle size and composition during the synthesis using the modified polyol process. One of the factors limiting their application in ultra-high-density magnetic storage media is the particle-to-particle composition, which affects the A1-to-L1(0) transformation as well as their magnetic properties. There are many controversies in the literature concerning the mechanism of the FePt formation, which seems to be the key to understanding the compositional chemical distribution. Our results convincingly show that, initially, Pt nuclei are formed due to reduction of Pt(acac)(2) by the diol, followed by heterocoagulation of Fe cluster species formed from Fe(acac)(3) thermal decomposition onto the Pt nuclei. Complete reduction of heterocoagulated iron species seems to involve a CO-spillover process, in which the Pt nuclei surface acts as a heterogeneous catalyst, leading to the improvement of the single-particle composition control and allowing a much narrower compositional distribution. Our results show significant decreases in the particle-to-particle composition range, improving the A1-to-L1(0) phase transformation and, consequently, the magnetic properties when compared with other reported methods.

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Föreliggande systematiska litteraturstudie syftade till att samla information och söka evidens för bröstcancerdrabbade kvinnors omvårdnadsbehov från sjuksköterskans i form av stöd för psykiska, sociala eller informativa behov. Sexton vetenskapliga artiklar valdes ut via databasen CINAHL (Cumulative Index to Nursing and Allied Health Literature) och fulltextdatabasen ELIN (Elecronic Library Information Navigator) för vidare granskning. Till sökningen användes sökorden breast*, cancer*, nurs* och support. Alla utvalda artiklar som härrör till syftet kvalitetsbedömdes genom på förhand bestämda granskningskriterier från modifierade förlagor efter Forsberg och Wengström (2003) och Willman, Bahtsevani och Stoltz (2007). Av resultatet framkom det att det fanns stark evidens för att kvinnor med bröstcancer har ett omvårdnadsbehov av socialt stöd, psykiskt stöd och även av information av sjuksköterskan. Omvårdnadsbehov som även kom fram i denna studie är kontinuitet i vården och personliga samtal med sjuksköterskan. Att få utöva sin religiösa tro, sin andlighet och utöva sin kulturella tillhörighet samt likaså känna förtroende är omvårdnadsbehov som blev uppenbarat i resultatet. Resultatet diskuterades utifrån Aaron Antonovskys omvårdnadsteori där känslan av sammanhang är central.

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Background: Family centred care (FCC) is currently a valued philosophy within neonatal care; an approach that places the parents at the heart of all decision-making and engagement in the care of their infant. However, to date, there is a lack of clarity regarding the definition of FCC and limited evidence of FCCs effectiveness in relation to parental, infant or staff outcomes. Discussion: In this paper we present a new perspective to neonatal care based on Aaron Antonovksy's Sense of Coherence (SOC) theory of well-being and positive health. Whilst the SOC was originally conceptualised as a psychological-based construct, the SOCs three underpinning concepts of comprehensibility, manageability and meaningfulness provide a theoretical lens through which to consider and reflect upon meaningful care provision in this particular care environment. By drawing on available FCC research, we consider how the SOC concepts considered from both a parental and professional perspective need to be addressed. The debate offered in this paper is not presented to reduce the importance or significance of FCC within neonatal care, but, rather, how consideration of the SOC offers the basis through which meaningful and effective FCC may be delivered. Practice based implications contextualised within the SOC constructs are also detailed. Summary: Consideration of the SOC constructs from both a parental and professional perspective need to be addressed in FCC provision. Service delivery and care practices need to be comprehensible, meaningful and manageable in order to achieve and promote positive well-being and health for all concerned.