1,659 research outputs found
Modulated Inflation
We have studied modulated inflation that generates curvature perturbation
from light-field fluctuation. As discussed in previous works, even if the
fluctuation of the inflaton itself does not generate the curvature perturbation
at the horizon crossing, fluctuation of a light field may induce fluctuation
for the end-line of inflation and this may lead to generation of cosmological
perturbation ``at the end of the inflation''. Our scenario is different from
those that are based on the fluctuations of the boundary of the inflaton
trajectory, as clearly explained in this paper by using the
formalism. In this paper, we will consider the perturbation of the inflaton
velocity that can be induced by a light field other than the inflaton. We also
explain the crucial difference from the standard multi-field inflation model.
We show concrete examples of the modulated inflation scenario in which
non-gaussianity can be generated. We also discuss the running of the
non-gaussianity parameter.Comment: 17pages, k^2/a^2 is included, accepted for publication in PL
Dolor, calidad de vida y estado anĂmico relacionados con la salud de pacientes ancianos hospitalizado
Objetivo.
A través de este estudio, se pretende establecer la relación existente entre la intensidad del dolor
percibida, la ansiedad, depresiĂłn y calidad de vida de pacientes ancianos hospitalizados.
MĂ©todo.
Presenta un
diseño de tipo transversal descriptivo. El muestreo se realizó de manera aleatoria estratificada (119 participantes).
Se evaluaron los niveles de ansiedad y depresiĂłn, asĂ como la intensidad del dolor que los participantes
reportaron durante la entrevista. Para esto, se utilizĂł la Escala de Ansiedad y DepresiĂłn de Goldberg (EADG),
el cuestionario Perfil de Salud de Nottingham (PSN) y la Escala Verbal Simple (EVS).
Resultados.
En general,
se observó que, en la medida en que el dolor aumentaba, empeoraban las áreas de calidad de vida evaluadas
con el PSN, asĂ como los niveles de ansiedad y depresiĂłn.
ConclusiĂłn.
Ante el deterioro de la calidad de vida
y su relaciĂłn con las respuestas emocionales asociadas a ansiedad y depresiĂłn, conforme la intensidad del
dolor, se deben realizar intervenciones de nivel primario y secundario que permitan el control del dolor, con
el fin de reducir el impacto en la salud mental de los adultos mayores, a partir de estrategias integradas entre
lo farmacolĂłgico y psicolĂłgico. Del mismo modo, se sugiere la creaciĂłn de programas intrahospitalarios que
incorporen terapias integrales que, a su vez, atiendan la dimensiĂłn emocional y afectiva de los pacientes
ancianos hospitalizados, con el propĂłsito de mejorar su calidad de vida
Large non-Gaussianity from two-component hybrid inflation
We study the generation of non-Gaussianity in models of hybrid inflation with
two inflaton fields, (2-brid inflation). We analyse the region in the parameter
and the initial condition space where a large non-Gaussianity may be generated
during slow-roll inflation which is generally characterised by a large f_NL,
tau_NL and a small g_NL. For certain parameter values we can satisfy
tau_NL>>f_NL^2. The bispectrum is of the local type but may have a significant
scale dependence. We show that the loop corrections to the power spectrum and
bispectrum are suppressed during inflation, if one assume that the fields
follow a classical background trajectory. We also include the effect of the
waterfall field, which can lead to a significant change in the observables
after the waterfall field is destabilised, depending on the couplings between
the waterfall and inflaton fields.Comment: 16 pages, 6 figures; v2: comments and references added, typos
corrected, matches published versio
Elliptic Inflation: Generating the curvature perturbation without slow-roll
There are many inflationary models in which inflaton field does not satisfy
the slow-roll condition. However, in such models, it is always difficult to
generate the curvature perturbation during inflation. Thus, to generate the
curvature perturbation, one must introduce another component to the theory. To
cite a case, curvatons may generate dominant part of the curvature perturbation
after inflation. However, we have a question whether it is unrealistic to
consider the generation of the curvature perturbation during inflation without
slow-roll. Assuming multi-field inflation, we encounter the generation of the
curvature perturbation during inflation without slow-roll. The potential along
equipotential surface is flat by definition and thus we do not have to worry
about symmetry. We also discuss about KKLT models, in which corrections lifting
the inflationary direction may not become a serious problem if there is a
symmetry enhancement at the tip (not at the moving brane) of the inflationary
throat.Comment: 27pages, 8figures, to appear in JCA
Targeting ribosomal G-quadruplexes with naphthalene-diimides as RNA polymerase I inhibitors for colorectal cancer treatment
Guanine quadruplexes (G4s) are non-canonical nucleic acid structures commonly found in regulatory
genomic regions. G4 targeting has emerged as a therapeutic approach in cancer. We have screened naph thalene-diimides (NDIs), a class of G4 ligands, in a cellular model of colorectal cancer (CRC). Here, we identify
the leading compound T5 with a potent and selective inhibition of cell growth by high-affinity binding to G4s in
ribosomal DNA, impairing RNA polymerase I (Pol I) elongation. Consequently, T5 induces a rapid inhibition of
Pol I transcription, nucleolus disruption, proteasome-dependent Pol I catalytic subunit A degradation and
autophagy. Moreover, we attribute the higher selectivity of carbohydrate-conjugated T5 for tumoral cells
to its preferential uptake through the overexpressed glucose transporter 1. Finally, we succinctly demon strate that T5 could be explored as a therapeutic agent in a patient cohort with CRC. Therefore, we report
a mode of action for these NDIs involving ribosomal G4 targeting
N-flation
The presence of many axion fields in four-dimensional string vacua can lead
to a simple, radiatively stable realization of chaotic inflation.Comment: 16 pages, 0 figures, latex; v2: added refs; v3: more refs, correction
to \S2.
Unraveling nanotopography of cell surface receptors
Cells communicate with their environment via surface receptors, but nanoscopic receptor organization with respect to complex cell surface morphology remains unclear. This is mainly due to a lack of accessible, robust and high-resolution methods. Here, we present an approach for mapping the topography of receptors at the cell surface with nanometer precision. The method involves coating glass coverslips with glycine, which preserves the fine membrane morphology while allowing immobilized cells to be positioned close to the optical surface. We developed an advanced and simplified algorithm for the analysis of single-molecule localization data acquired in a biplane detection scheme. These advancements enable direct and quantitative mapping of protein distribution on ruffled plasma membranes with near isotropic 3D nanometer resolution. As demonstrated successfully for CD4 and CD45 receptors, the described workflow is a straightforward quantitative technique to study molecules and their interactions at the complex surface nanomorphology of differentiated metazoan cells
Small Stem Total Hip Arthroplasty in Hypoplasia of the Femur
Total hip arthroplasty in hypoplastic femurs is technically difficult and the incidence of complications and aseptic loosening is relatively high. Cemented, uncemented, off-the-shelf, and custom-made stems all have been advocated in these cases. From 1978 to 1997, we performed 86 total hip arthroplasties in 77 patients with a hypoplastic femur using a cemented, off-the-shelf, small, curved, cobalt-chromium stem. We hypothesized results equaled those of the identical but larger-sized stems in normal-sized femora which were used as comparisons. Clinical and radiographic evaluations were performed. Minimum followup was 4.2 years (mean, 12 years; range, 4.2–20.3 years); mean Harris hip score was 88, and mean hip flexion was 104°. Six stems were revised: four because of aseptic loosening, one after a femoral fracture, and one because of malpositioning. Complications included one perforation and one fracture of the femur, one fracture, one nonunion of the greater trochanter, and one deep infection. Implant survivorship for all hips at 15 years with aseptic revision of the stem as the end point was 90% (confidence interval, 82–99) which equaled results of the larger stems. The small off-the-shelf cemented Weber stem has a high long-term survival and a low complication rate. Survival compares favorably with other small-sized total hip systems
Approach to map nanotopography of cell surface receptors
Cells communicate with their environment via surface receptors, but nanoscopic receptor organization with respect to complex cell surface morphology remains unclear. This is mainly due to a lack of accessible, robust and high-resolution methods. Here, we present an approach for mapping the topography of receptors at the cell surface with nanometer precision. The method involves coating glass coverslips with glycine, which preserves the fine membrane morphology while allowing immobilized cells to be positioned close to the optical surface. We developed an advanced and simplified algorithm for the analysis of single-molecule localization data acquired in a biplane detection scheme. These advancements enable direct and quantitative mapping of protein distribution on ruffled plasma membranes with near isotropic 3D nanometer resolution. As demonstrated successfully for CD4 and CD45 receptors, the described workflow is a straightforward quantitative technique to study molecules and their interactions at the complex surface nanomorphology of differentiated metazoan cells
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