SAMplus: adaptive optics at optical wavelengths for SOAR

Adaptive Optics (AO) is an innovative technique that substantially improves the optical performance of ground-based telescopes. The SOAR Adaptive Module (SAM) is a laser-assisted AO instrument, designed to compensate ground-layer atmospheric turbulence in near-IR and visible wavelengths over a large Field of View. Here we detail our proposal to upgrade SAM, dubbed SAMplus, that is focused on enhancing its performance in visible wavelengths and increasing the instrument reliability. As an illustration, for a seeing of 0.62 arcsec at 500 nm and a typical turbulence profile, current SAM improves the PSF FWHM to 0.40 arcsec, and with the upgrade we expect to deliver images with a FWHM of $\approx0.34$ arcsec -- up to 0.23 arcsec FWHM PSF under good seeing conditions. Such capabilities will be fully integrated with the latest SAM instruments, putting SOAR in an unique position as observatory facility.Comment: To appear in Proc. SPIE 10703 (Ground-based and Airborne Instrumentation for Astronomy VII; SPIEastro18

An open and parallel multiresolution framework using block-based adaptive grids

A numerical approach for solving evolutionary partial differential equations in two and three space dimensions on block-based adaptive grids is presented. The numerical discretization is based on high-order, central finite-differences and explicit time integration. Grid refinement and coarsening are triggered by multiresolution analysis, i.e. thresholding of wavelet coefficients, which allow controlling the precision of the adaptive approximation of the solution with respect to uniform grid computations. The implementation of the scheme is fully parallel using MPI with a hybrid data structure. Load balancing relies on space filling curves techniques. Validation tests for 2D advection equations allow to assess the precision and performance of the developed code. Computations of the compressible Navier-Stokes equations for a temporally developing 2D mixing layer illustrate the properties of the code for nonlinear multi-scale problems. The code is open source

Endoscopy Timing in Patients with Acute Upper Gastrointestinal Bleeding.

BACKGROUND/AIMS: The role of very early (≤12 hours) endoscopy in nonvariceal upper gastrointestinal bleeding is controversial. We aimed to compare results of very early and early (12-24 hours) endoscopy in patients with upper gastrointestinal bleeding demonstrating low-risk versus high-risk features and nonvariceal versus variceal bleeding. METHODS: : This retrospective study included patients with nonvariceal and variceal upper gastrointestinal bleeding. The primary outcome was a composite of inpatient death, rebleeding, or need for surgery or intensive care unit admission. Endoscopy timing was defined as very early and early. We performed the analysis in two subgroups: (1) high-risk vs. low-risk patients and (2) variceal vs. nonvariceal bleeding. RESULTS: : A total of 102 patients were included, of whom 59.8% underwent urgent endoscopy. Patients who underwent very early endoscopy received endoscopic therapy more frequently (p=0.001), but there was no improvement in other clinical outcomes. Furthermore, patients at low risk and with nonvariceal bleeding who underwent very early endoscopy had a higher risk of the composite outcome. CONCLUSION: s: Very early endoscopy does not seem to be associated with improved clinical outcomes and may lead to poorer outcomes in specific populations with upper gastrointestinal bleeding. The actual benefit of very early endoscopy remains controversial and should be further clarified.info:eu-repo/semantics/publishedVersio

Antony and Cleopatra

Analysis done 199

Isolation and characterization of a lignin-like polymer of the cork of Quercus suber L

A lignin-like polymer was successfully extracted from the cork of Quercus suber L. using an organosolv-based technique. This material was characterized by elemental analysis, functional group analysis, nitrobenzene oxidation followed by HPLC analysis of the oxidation products, FTIR and liquid I3C NMR. The evidence thus obtained indicated that the extracted material was composed mainly of a lignin-like polymer covalently bound to residual aliphatic structures which are not present in common lignins and which have been assigned to suberin. The latter is likely to be attached to the oxygenated side chains of the phenolic polymer but bonding through the aromatic ring can also be envisaged. No residual carbohydrates were detected. The phenolic polymer, composed mainly of guaiacyl-type units and small amounts of syringyl-type units, had a low methoxy content and a high degree of condensation. This polymer showed the presence of a fraction containing CeCn units with n < 3 or even n < 2.info:eu-repo/semantics/publishedVersio

An ensemble approach to quantify global mean sea-level rise over the 20th century from tide gauge reconstructions

We present an ensemble approach to quantify historical global mean sea-level (GMSL) rise based on tide gauge reconstructions. This approach combines the maximum internal uncertainty across the ensemble with an estimate of structural uncertainty to provide a conservative estimate of the total uncertainty. Comparisons of GMSL rise over the 20th century based on deltas and linear trends (and their respective uncertainties) are consistent with past Intergovernmental Panel on Climate Change assessments and show good agreement with satellite altimeter timeseries. Sensitivity tests show that our estimates of GMSL rise are robust to the choice of reference period and central estimate timeseries. The methods proposed in this study are generic and could be easily applied to other global or regional climate change indicators.Non peer reviewe

Successful pain relief in chronic low back pain patients undergoing multimodal physiotherapy are associated with an early response to treatment

Trabalho apresentado no 10th Congress of European Pain Federation (EFIC), 6-9 setembro 2017, Copenhaga, DinamarcaN/

Use of p53-Silenced Endothelial Progenitor Cells to Treat Ischemia in Diabetic Peripheral Vascular Disease.

Background Peripheral vascular disease is a major diabetes mellitus‐related complication. In this study, we noted that expressions of proapoptotic p53 gene and its downstream cascade gene such as p21 are upregulated in hyperglycemia. Therefore, we investigated whether p53‐ and p21‐silenced endothelial progenitor cells (EPCs) were able to survive in hyperglycemic milieu, and whether transplantation of either p53 knockout (KO) or p21KO or p53‐ and p21‐silenced EPCs could improve collateral vessel formation and blood flow in diabetic vaso‐occlusive peripheral vascular disease mouse models. Methods and Results We transplanted p53 and p21KO mouse EPCs (mEPCs) into streptozotocin–induced diabetic (type 1 diabetes mellitus model) C57BL/6J and db/db (B6.BKS(D)‐Leprdb/J) (type 2 model) post–femoral artery occlusion. Similarly, Ad‐p53–silenced and Ad‐p21–silenced human EPCs (CD34+) cells were transplanted into streptozotocin‐induced diabetic NOD.CB17‐Prkdcscid/J mice. We measured blood flow at 3, 7, and 10 days and hindlimb muscles were obtained postsacrifice for mRNA estimation and CD31 staining. Enhanced blood flow was noted with delivery of p53 and p21KO mEPCs in streptozotocin‐induced diabetic C57BL/6J mice. Similar results were obtained when human Ad‐p53shEPCs(CD34+) and Ad‐p21shEPCs(CD34+) were transplanted into streptozotocin‐induced nonobese diabetic severe combined immunodeficiency mice. Gene expression analysis of p53 and p21KO EPCs transplanted hindlimb muscles showed increased expression of endothelial markers such as endothelial nitric oxide synthase, vascular endothelial growth factor A, and platelet endothelial cell adhesion molecule 1. Similarly, quantitative reverse transcriptase polymerase chain reaction of human Ad‐p53shEPCs (CD34+)– and Ad‐p21shEPCs (CD34+)–transplanted hindlimb muscles also showed increased expression of endothelial markers such as vascular endothelial growth factor A, noted primarily in the p53‐silenced EPCs group. However, such beneficial effect was not noted in the db/db type 2 diabetic mouse models. Conclusions Transient silencing of p53 using adenoviral vector in EPCs may have a therapeutic role in diabetic peripheral vascular disease

Genetic variability of an endangered Bromeliaceae species (Pitcairnia albiflos) from the Brazilian Atlantic rainforest.

Pitcairnia albiflos is a Bromeliaceae species endemic to Brazil that has been included as data-deficient in the extinction risk list of Brazilian flora. We analyzed genetic variability in P. albiflos populations using RAPD markers to investigate population structure and reproductive mechanisms and also to evaluate the actual extinction risk level of this species. Leaves of 56 individuals of P. albiflos from three populations were collected: Urca Hill (UH, 20 individuals), Chacrinha State Park (CSP, 24 individuals) and Tijuca National Park (TNP, 12 individuals). The RAPD technique was effective in characterizing the genetic diversity in the P. albiflos populations since it was possible to differentiate the populations and to identify exclusive bands for at least two of them. Even if there is low genetic diversity among them (CSP-UH = 0.463; CSP-TNP = 0.440; UH-TNP = 0.524), the populations seem to be isolated according to the low genetic diversity observed within them (H(pop) CSP = 0.060; H(pop) UH = 0.042; H(pop) TNP = 0.130). This fact might be the result of clonal and self-reproduction predominance and also from environmental degradation around the collection areas. Consequently, it would be important to protect all populations both in situ and ex situ to prevent the decrease of genetic variability. The low genetic variability among individuals of the same population confirms the inclusion of this species as critically endangered in the risk list for Brazilian flora