1,826 research outputs found
KAM-tori near an analytic elliptic fixed point
We study the accumulation of an elliptic fixed point of a real analytic
Hamiltonian by quasi-periodic invariant tori. We show that a fixed point with
Diophantine frequency vector \o_0 is always accumulated by invariant complex
analytic KAM-tori. Indeed, the following alternative holds: If the Birkhoff
normal form of the Hamiltonian at the invariant point satisfies a R\"ussmann
transversality condition, the fixed point is accumulated by real analytic
KAM-tori which cover positive Lebesgue measure in the phase space (in this part
it suffices to assume that \o_0 has rationally independent coordinates). If
the Birkhoff normal form is degenerate, there exists an analytic subvariety of
complex dimension at least passing through 0 that is foliated by complex
analytic KAM-tori with frequency . This is an extension of previous
results obtained in \cite{EFK} to the case of an elliptic fixed point
Valoración del sufrimiento en pacientes con cáncer avanzado
El cáncer avanzado trae consigo múltiples temores asociados a los sÃntomas fÃsicos presentes o potenciales, a los cambios emocionales y afectivos, a inquietudes existenciales y una variedad de preocupaciones que contribuyen de manera conjunta y dinámica al sufrimiento, entendido como la amenaza a la integridad y al agotamiento de recursos para hacerle frente. La evaluación del sufrimiento requiere de la visión integral y el estilo de trabajo interdisciplinario propios de los Cuidados Paliativos, para abordar la diversidad de experiencias y preocupaciones del enfermo y su familia. El presente artÃculo tiene como objetivo revisar el concepto de sufrimiento, asà como los métodos para evaluar dicha experiencia en el contexto de enfermos de cáncer en estadÃos avanzados de la enfermedad. Aunque ha habido importantes avances respecto a las estrategias y protocolos dirigidos a mejorar el bienestar de pacientes con enfermedades que amenazan la vitalidad, aún se requiere mayor investigación en torno a la valoración del sufrimiento, dada su complejidad.Advanced cancer entails multiple fears associated to actual or potential physical symptoms as well as emotional and affective changes, existential issues and a variety of concerns, all contributing dynamically to suffering, which implies a threat to integrity and the exhaustion of resources to cope with it. Suffering assessment requires a comprehensive and interdisciplinary approach to manage the diversity of experiences and concerns of the patient and family, found mostly in Palliative Care settings. The article reviews the concept and assessment of suffering in advanced cancer patients. Even though there have been important advances in the development of strategies and protocols to maintain and improve patient’s well-being, there is still need for research in suffering evaluation given the complexity of the experience
City Kids: Transforming Racial Baggage
This is a book review of City Kids: Transforming Racial Baggage (2016) by Maria Kromidas
Synthesis and self-assembly of lipid (DMPC)-conjugated gold nanoparticles
Bio-conjugated nanomaterials play a promising role in the development of
novel supramolecular structures, molecular machines, and biosensing devices. In
this study, lipid-conjugated gold nanoparticles were synthesized and allowed to
form a self-assembled monolayer structure. The nanoparticles were prepared by a
phase transfer method, which involved the reduction of potassium
tetrachloroaurate (III) by sodium citrate in an aqueous solution and the
simultaneous transfer of the reduced species to an organic medium containing
DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine). The gold nanoparticles were
characterized using UV-Vis spectroscopy and dynamic light scattering (DLS)
particle-size analysis. In addition, the resulting nanoparticles were examined
using transmission electron microscopy (TEM). The Langmuir-Blodgett (LB)
technique was used to assemble the DMPC-capped nanoparticles onto a water
subphase at room temperature. The measurement of the compression isotherm
confirmed the assemblage of lipid capped gold nanoparticles. This method of
synthesis of ordered structures utilizing molecular interactions of lipids will
be useful in developing novel metamaterials and nanocircuits.Comment: 7 pages, 5 Figure
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