Non-Gaussianity after many-field reheating

International audienceWe numerically investigate reheating after quadratic inflation with up to 65 fields, focusing on the production of non-Gaussianity. We consider several sets of initial conditions, masses, and decay rates. As expected, we find that the reheating phase can have a significant effect on the non-Gaussian signal, but that for this number of fields a detectable level of non-Gaussianity requires the initial conditions, mass range, and decay rates to be ordered in a particular way. We speculate on whether this might change in the N-flation limit

Long-term survival in a patient with brain metastases of papillary thyroid carcinoma

We present the case of a 43-year-old woman who underwent total thyroidectomy with bilateral lymphadenectomy for a papillary thyroid carcinoma (PTC), solid variant (T4bN1bMx), with V600E BRAF mutation. After ablative therapy, she presented undetectable thyroglobulin (Tg) but progressively increasing anti-Tg antibodies (TgAbs). During follow-up, nodal, lung and brain metastases were identified. She was submitted to surgical excision of lung lesions, radiosurgery of brain metastases and five radioiodine treatments. The latest brain MRI showed no lesions, pulmonary CT showed stable micronodules and there was progressive reduction in TgAbs. This is a peculiar case of a PTC with lung and brain metastatic lesions detected through TgAbs. Initial histological and molecular study suggested a more aggressive clinical behaviour, which was eventually confirmed. Although PTC brain metastases are extremely rare and present poor prognosis, our patient presented a good response to treatment and longer survival than usually reported for similar cases.info:eu-repo/semantics/publishedVersio

Attractor behaviour in multifield inflation

We study multifield inflation in scenarios where the fields are coupled non-minimally to gravity via $\xi_I(\phi^I)^n g^{\mu\nu}R_{\mu\nu}$, where $\xi_I$ are coupling constants, $\phi^I$ the fields driving inflation, $g_{\mu\nu}$ the space-time metric, $R_{\mu\nu}$ the Ricci tensor, and $n>0$. We consider the so-called $\alpha$-attractor models in two formulations of gravity: in the usual metric case where $R_{\mu\nu}=R_{\mu\nu}(g_{\mu\nu})$, and in the Palatini formulation where $R_{\mu\nu}$ is an independent variable. As the main result, we show that, regardless of the underlying theory of gravity, the field-space curvature in the Einstein frame has no influence on the inflationary dynamics at the limit of large $\xi_I$, and one effectively retains the single-field case. However, the gravity formulation does play an important role: in the metric case the result means that multifield models approach the single-field $\alpha$-attractor limit, whereas in the Palatini case the attractor behaviour is lost also in the case of multifield inflation. We discuss what this means for distinguishing between different models of inflation.Comment: 20 pages, 6 figures. Typos corrected and references added. This is an author-created, un-copyedited version of an article published in JCAP. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at https://iopscience.iop.org/article/10.1088/1475-7516/2018/06/032/pd

Relations between Cardiac and Visual Phenotypes in Diabetes: A Multivariate Approach

Cardiovascular disease and diabetes represent a major public health concern. The former is the most frequent cause of death and disability in patients with type 2 diabetes, where left ventricular dysfunction is highly prevalent. Moreover, diabetic retinopathy is becoming a dominant cause of visual impairment and blindness. The complex relation between cardiovascular disease and diabetic retinopathy as a function of ageing, obesity and hypertension remains to be clarified. Here, we investigated such relations in patients with diabetes type 2, in subjects with neither overt heart disease nor advanced proliferative diabetic retinopathy. We studied 47 patients and 50 controls, aged between 45 and 65 years, equally distributed according to gender. From the 36 measures regarding visual structure and function, and the 11 measures concerning left ventricle function, we performed data reduction to obtain eight new derived variables, seven of which related to the eye, adjusted for age, gender, body mass index and high blood pressure using both discriminant analysis (DA) and logistic regression (LR). We found moderate to strong correlation between left ventricle function and the eye constructs: minimum correlation was found for psychophysical motion thresholds (DA: 0.734; LR: 0.666), while the maximum correlation was achieved with structural volume density in the neural retina (DA: 0.786; LR: 0.788). Controlling the effect of pairwise correlated visual constructs, the parameters that were most correlated to left ventricle function were volume density in retina and thickness of the retinal nerve fiber layers (adjusted multiple R2 is 0.819 and 0.730 for DA and LR), with additional contribution of psychophysical loss in achromatic contrast discrimination. We conclude that visual structural and functional changes in type 2 diabetes are related to heart dysfunction, when the effects of clinical, demographic and associated risk factors are taken into account, revealing a genuine relation between cardiac and retinal diabetic phenotypes.info:eu-repo/semantics/publishedVersio

Impact of aperture separation on wind-driven single-sided natural ventilation

This paper presents a study of the impact of horizontal aperture separation in single-sided ventilation flows with two apertures (SS2). The study is based on wind tunnel measurements and dimensional analysis. The results show that the SS2 ventilation flow rate, scaled with incoming wind velocity and aperture area, depends on the incoming wind angle relative to the aperture façade, $θ$, and on the aperture separation scaled by building width, $s$′. For most wind angles, the ventilation flow increases as the square-root of $s$′. This study also identified a novel flow driving mechanism – vortex shedding: when the ventilation openings are on the leeward side of the building and the wind is nearly head-on, the flow is driven by a pumping mechanism due to vortex shedding.The authors gratefully acknowledge the contribution of staff at CPP Wind Engineering, Inc., for running the wind tunnel tests that produced the data used to develop our model; and financial support for one of us (GCG) from Instituto Dom Luiz (UID/GEO/50019/ 2013). The work described in this paper was carried out under California Energy Commission contract 500-10-025, and their financial support is gratefully acknowledged

Variação nos níveis de herbivoria foliar em dois manguezais da baía de Paranaguá (Paraná – Brasil)

Recent studiesemphasize herbivory’s importance in mangrove’s carbon flux. Chemio- physical characteristics of the environment caninfluence leaf consumption, leading to differences in herbivory levels. This work evaluates possible differences in thedegree of leaf consumption in two similarly structured mangrove forests submitted to different levels of pollution. In eachforest, a 150 m transect was established perpendicularly to the waterline, and each one was divided in three 50 mstrata. Thirty leaves from each of the local species (Rhizophora mangle, Avicennia schaueriana e Lagunculariaracemosa) of mangrove were randomly collected, in a standardized way, in each strata. The samples were processedand herbivory levels were calculated through specific softwares. No differences were found between the forests norbetween the stratum. The lack of differences between the stratum could be a consequence of the homogeneousdistribution of the herbivorous in the forests. Furthermore, the fact that the forests present similar physiographicstructures – in terms of tree’s height, composition and distribution - can be ruling folivory levels, being more importantthan differences in soil and leaf composition.Recent studiesemphasize herbivory’s importance in mangrove’s carbon flux. Chemio- physical characteristics of the environment caninfluence leaf consumption, leading to differences in herbivory levels. This work evaluates possible differences in thedegree of leaf consumption in two similarly structured mangrove forests submitted to different levels of pollution. In eachforest, a 150 m transect was established perpendicularly to the waterline, and each one was divided in three 50 mstrata. Thirty leaves from each of the local species (Rhizophora mangle, Avicennia schaueriana e Lagunculariaracemosa) of mangrove were randomly collected, in a standardized way, in each strata. The samples were processedand herbivory levels were calculated through specific softwares. No differences were found between the forests norbetween the stratum. The lack of differences between the stratum could be a consequence of the homogeneousdistribution of the herbivorous in the forests. Furthermore, the fact that the forests present similar physiographicstructures – in terms of tree’s height, composition and distribution - can be ruling folivory levels, being more importantthan differences in soil and leaf composition