332 research outputs found
On the seasonal variability of the Canary Current and the Atlantic Meridional Overturning Circulation
Author Posting. © American Geophysical Union, 2017. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 122 (2017): 4518–4538, doi:10.1002/2017JC012774.The Atlantic Meridional Overturning Circulation (AMOC) is continually monitored along 26°N by the RAPID-MOCHA array. Measurements from this array show a 6.7 Sv seasonal cycle for the AMOC, with a 5.9 Sv contribution from the upper mid-ocean. Recent studies argue that the dynamics of the eastern Atlantic is the main driver for this seasonal cycle; specifically, Rossby waves excited south of the Canary Islands. Using inverse modeling, hydrographic, mooring, and altimetry data, we describe the seasonal cycle of the ocean mass transport around the Canary Islands and at the eastern boundary, under the influence of the African slope, where eastern component of the RAPID-MOCHA array is situated. We find a seasonal cycle of −4.1 ± 0.5 Sv for the oceanic region of the Canary Current, and +3.7 ± 0.4 Sv at the eastern boundary. This seasonal cycle along the eastern boundary is in agreement with the seasonal cycle of the AMOC that requires the lowest contribution to the transport in the upper mid-ocean to occur in fall. However, we demonstrate that the linear Rossby wave model used previously to explain the seasonal cycle of the AMOC is not robust, since it is extremely sensitive to the choice of the zonal range of the wind stress curl and produces the same results with a Rossby wave speed of zero. We demonstrate that the seasonal cycle of the eastern boundary is due to the recirculation of the Canary Current and to the seasonal cycle of the poleward flow that characterizes the eastern boundaries of the oceans.RAPROCAN Project ;
Instituto Español de Oceanografía; and as part of the SeVaCan project Grant Number: CTM2013-48695;
Ministerio de Economía y Competividad;
Apoyo al Personal Investigador en Formación2017-12-0
Intervención farmacéutica en gestante: Derivación al médico para modificar la posición del feto
Se presenta en la farmacia una paciente habitual cuyo primer embarazo hemos seguido desde el principio. Durante los meses de gestación, la mujer no ha sufrido ningún problema importante, pero nos comenta que en la última ecografía el ginecólogo le ha informado que el feto se encuentra de nalgas y que es posible que le tengan que realizar una cesárea. La gestante se encuentra asustada ya que desea tener un parto natural por vía vaginal y nos pregunta si existe alguna técnica que ayude a colocar el feto, evitando la cesárea
Concretos sustentables expuestos a altas temperaturas
Concretos fueron elaborados reemplazando cemento Portland ordinario por nano-SiO2 geotérmica y humo de sílice. Se curaron a 20ºC y 100% de humedad hasta 7 años y después fueron expuestos a altas temperaturas (350°C, 550°C y 750°C). Se les evaluó la velocidad de ultrasonidos (UPV), análisis termogravimétrico/diferencial (TG/DTA), difracción de rayos X (DRX) y microscopía electrónica de barrido (MEB). La pérdida de peso y la reducción en la UPV fue mayor para los especímenes adicionados (NSG y HS) en comparación con el espécimen de referencia (CPC 100%), además se apreció una mayor degradación en la microestructura de los especímenes con adiciones
Assessing the performance of a handheld laser scanning system for individual tree mapping—A mixed forests showcase in Spain
Producción CientíficaThe use of mobile laser scanning to survey forest ecosystems is a promising, scalable technology to describe the 3D structure of forests at a high resolution. We use a structurally complex, mixed-species Mediterranean forest to test the performance of a mobile Handheld Laser Scanning (HLS) system to estimate tree attributes within a forest patch in central Spain. We describe the different stages of the HLS approach: field position, ground data collection, scanning path design, point cloud processing, alignment between detected trees and measured reference trees, and finally, the assessment of main tree structural attributes diameter at breast height (DBH) and tree height considering species and tree size as control factors. We surveyed 418 reference trees to account for omission and commission error rates over a 1 ha plot divided into 16 sections and scanned using two different scanning paths. The HLS-based approach reached a high of 88 and 92% tree detection rate for the best combination of scanning path and point cloud processing modes for the HLS system. The root mean squared errors for DBH estimates varied between species: errors for Pinus pinaster were below 2 cm for Scan 02. Quercus pyrenaica, and Alnus glutinosa showed higher error rates. We observed good agreement between ALS and HLS estimates for tree height, highlighting differences to field measurements. Despite the complexity of the mixed forest area surveyed, our results show that HLS is highly efficient at detecting tree locations, estimating DBH, and supporting tree height measurements as confirmed with airborne laser data used for validation. This study is one of the first HLS-based studies conducted in the Mediterranean mixed forest region, where variability in tree allometries and spacing and the presence of natural regeneration pose challenges for the HLS approach. HLS is a feasible, time-efficient, scalable technology for tree mapping in mixed forests with potential to support forest monitoring programmes such as national forest inventories lacking three-dimensional, remote sensing data to support field measurements.European Union’s Horizon 2020 and Innovation Program Marie Skłodowska-Curie - (Grant 956355)Junta de Castilla y León y Fondo Europeo de Desarrollo Regional (FEDER) - (projects “CLU‑2019‑01 and CL‑EI‑2021‑05—iuFOR Institute Unit of Excellence”)Fondo Europeo de Desarrollo Regional (FEDER), project Interreg COMFOR‑SUDOE - (grant SOE4/P1/E1012
Insulin Resistance Is Not Increased in Inflammatory Bowel Disease Patients but Is Related to Non-Alcoholic Fatty Liver Disease
Background: Insulin resistance (IR) has been linked to inflammatory states. The aim of this study was to determine whether IR is increased in a cohort of inflammatory bowel disease (IBD) patients with low disease activity. We additionally intended to establish which factors were the determinants of IR in this population, including the presence of nonalcoholic fatty liver disease (NAFLD).
Methods: Cross-sectional study encompassing 151 IBD patients and 174 non-diabetic controls. Insulin and C-peptide serum levels and IR and beta cell function (%B) indices based on homoeostatic model assessment (HOMA2) were assessed in patients and controls. Liver stiffness as measured by transient elastography, and the presence of NAFLD detected via ultrasound were additionally assessed. A multivariable regression analysis was performed to evaluate the differences in IR indexes between patients and controls, and to determine which predictor factors were associated with IR in IBD patients.
Results: Neither HOMA2-IR (beta coef. -0.26 {95%CI -0.64-0.13}, p = 0.19) nor HOMA2-%B (beta coef. 15 {95%CI -14-44}, p = 0.31) indexes differed between patients and controls after fully multivariable analysis. Among classic IR risk factors, obesity, abdominal circumference, and triglycerides significantly and positively correlated with IR indexes in IBD patients. However, most features related to IBD, such as disease patterns, disease activity, and inflammatory markers, were not associated with IR. The presence of NAFLD was independently and significantly associated with beta cell dysfunction in patients with IBD (HOMA2-B grade 4, 251 ± 40 vs. grade 1, 107 ± 37, p = <0.001).
Conclusions: IR is not increased in IBD patients with low disease activity compared to controls. However, the presence of NAFLD favors the development of IR in patients with IBD.This work was supported by a grant to I.F-A. from the Spanish Ministry of Health, Subdirección General de Evaluación y Fomento de la Investigación, Plan Estatal de Investigación Científica y Técnica y de Innovación 2013–2016 and by Fondo Europeo de Desarrollo Regional-FEDER-(Fondo de Investigaciones Sanitarias, FIS PI14/00394, PI17/00083)
Carotid Plaque Assessment Reclassifies Patients with Inflammatory Bowel Disease into Very-High Cardiovascular Risk
The addition of carotid ultrasound into cardiovascular (CV) risk scores has been found to be effective in identifying patients with chronic inflammatory diseases at high-CV risk. We aimed to determine if its use would facilitate the reclassification of patients with inflammatory bowel disease (IBD) into the very high-CV-risk category and whether this may be related to disease features. In this cross-sectional study encompassing 186 IBD patients and 175 controls, Systematic Coronary Risk Evaluation (SCORE), disease activity measurements, and the presence of carotid plaques by ultrasonography were assessed. Reclassification was compared between patients and controls. A multivariable regression analysis was performed to evaluate if the risk of reclassification could be explained by disease-related features and to assess the influence of traditional CV risk factors on this reclassification. After evaluation of carotid ultrasound, a significantly higher frequency of reclassification was found in patients with IBD compared to controls (35% vs. 24%, p = 0.030). When this analysis was performed only on subjects included in the SCORE low-CV-risk category, 21% IBD patients compared to 11% controls (p = 0.034) were reclassified into the very high-CV-risk category. Disease-related data, including disease activity, were not associated with reclassification after fully multivariable regression analysis. Traditional CV risk factors showed a similar influence over reclassification in patients and controls. However, LDL-cholesterol disclosed a higher effect in controls compared to patients (beta coef. 1.03 (95%CI 1.02-1.04) vs. 1.01 (95%CI 1.00-1.02), interaction p = 0.035) after adjustment for confounders. In conclusion, carotid plaque assessment is useful to identify high-CV risk IBD patients.Funding: This work was supported by a grant to I.F-A. from the Spanish Ministry of Health, Subdirección General de Evaluación y Fomento de la Investigación, Plan Estatal de Investigación Científica y Técnica y de Innovación 2013–2016 and by Fondo Europeo de Desarrollo Regional—FEDER—(Fondo de Investigaciones Sanitarias, FIS PI14/00394, PI17/00083)
Beta-3 adrenergic receptor blockade prevents alterations in feeding behavior in lymphoma-bearing mice in a sex-dependent manner
Introduction: Cancer cachexia is a metabolic syndrome defined by an ongoing loss of adipose and muscular tissue and is characterized by a reduced food intake. Local b-3 adrenergic receptor activation in adipose tissue induces lipolysis, whereas b-3 signaling in tumors has been shown to be tumorigenic in some cancer models. Therefore, b-3 signaling may be a therapeutic target in cancer cachexia. The aim of this study was to assess the role of b-3 adrenergic signaling in feeding behavior, body composition, and tumor progression in the L5178Y-R murine lymphoma model.
Methods: In our study we used BALB/c mice of both sexes, which were divided in tumor-free and tumor-bearing groups. For the tumor model, L5178Y-R lymphoma cells were subcutaneously administered into animals right flank. These groups of mice intraperitoneally received L-748,337, a beta-3 antagonist, at a 50 mg/kg/day dose, starting the day after tumor implantation. Food and water intake were monitored every other day and body mass index (BMI) was calculated at the end of the experiment. Animals were euthanized for necropsy, when endpoint criteria were achieved. Transcriptional expression of Ucp-1, a molecular marker of thermogenesis, was quantified in interscapular adipose tissue.
Results: We observed a 15% and 35% reduction in food intake in tumor-bearing male and female mice, respectively. This effect was not observed in male mice treated with the b-3 adrenergic receptor antagonist L-748,337. In females, such an effect persisted despite beta-3 blocking. Reduced water intake was also observed in tumor-bearing animals, which was not altered by beta-3 antagonism. We also observed that tumor-free mice of both sexes showed reduced water intake after L-748,337 treatment. Furthermore, reduced BMI was observed in tumor-bearing animals of both sexes, which was not changed by b-3 blocking. Interscapular adipose tissue loss was observed in females (51.06%) but not in males. Additionally, 1.7-fold and 4.4-fold reduction in Ucp-1 gene expression was shown in tumor-bearing males and females, respectively. Decreased final tumor weight was observed only in tumor-bearing females treated with L-748,337 (p \u3c 0.05).
Conclusion: In L5178Y-R tumor-bearing BALB/c mice, selective blocking of beta-3 adrenergic signaling prevents alterations in food intake in a sex-dependent manner
QRISK3 performance in the assessment of cardiovascular risk in patients with inflammatory bowel disease
Inflammatory bowel disease (IBD) has been described as an independent risk factor for the development of cardiovascular (CV) disease. Since the QRESEARCH risk estimator version 3 (QRISK3) calculator was recently proposed to assess CV in the general population, our objective was to compare the predictive ability of QRISK3 with that of a well-established European CV risk calculator, the Systematic Coronary Risk Assessment (SCORE), to identify the presence of subclinical carotid atherosclerosis in patients with IBD. In all, 186 patients with IBD and 178 controls were recruited. The presence of subclinical atherosclerosis was evaluated by carotid ultrasound to identify carotid plaque and the thickness of the carotid intima-media (cIMT). QRISK3 and SCORE were calculated. The relationship of QRISK3 and SCORE with each other and with the presence of subclinical carotid atherosclerosis (both carotid plaque and cIMT) was studied in patients and controls. SCORE (0.2 (interquartile range 0.1-0.9) vs. 0.4 (0.1-1.4), p = 0.55) and QRISK3 1.7 ((0.6-4.6) vs. 3.0 (1.0-7.8), p = 0.16) absolute values did not differ between patients and controls. QRISK3 and SCORE correlated equally with cIMT within both populations. However, SCORE correlation with cIMT was found to be significantly lower in patients with IBD when compared to controls (Spearman's Rho 0.715 vs. 0.587, p = 0.034). Discrimination analysis of both calculators with carotid plaque was similar within both populations. Nevertheless, in patients with IBD, QRISK3 showed a trend toward a higher discrimination (QRISK3 area under the curve 0.812 (95%CI 0.748-0.875) vs. SCORE 0.790 (95%CI 0.723-0.856), p = 0.051). In conclusion, QRISK3 discrimination for subclinical atherosclerosis is optimal and equivalent to that of SCORE in IBD patients. However, our findings highlight the role of QRISK3 as an appropriate tool for the assessment of CV risk in patients with IBD.Funding: This work was supported by a grant to I.F-A. from the Spanish Ministry of Health, Subdirección General de Evaluación y Fomento de la Investigación, Plan Estatal de Investigación Científica y Técnica y de Innovación 2013–2016, and by Fondo Europeo de Desarrollo Regional-FEDER-(Fondo de Investigaciones Sanitarias, FIS PI14/00394, PI17/00083)
Life history of an anticyclonic eddy
19 pages, 11 figures, 1 table, supporting information https://doi.org/10.1029/2004JC002526We use the trajectory of three buoys dragged below the surface mixed layer, together with sea surface temperature imagery, to examine the evolution of an anticyclonic warm-core eddy since its generation by the Canary Islands. Two buoys remain within the eddy during some 100 days, and the third one remains almost 200 days, while drifting southwestward up to 500 km with the mean Canary Current. The eddy merges with several younger anticyclonic and cyclonic eddies, in each occasion, suffering substantial changes. The eddy core, defined as a region with near-solid-body-type rotation and radial convergence, initially occupies the whole eddy. After interacting with another vortex the inner core markedly slows down, although it continues displaying radial convergence and relatively small radial oscillations, and an uncoupled outer ring is formed or enhanced, which revolves even more slowly and displays large radial fluctuations. The vortex extensive life is consistent with its inertially stable character and observations of radial convergence. A very simple model of vortex merging, where cylinders fuse conserving mass and angular momentum, gives fair results. The observations suggest that the eddy changes, as the result of its own slow evolution and sporadic mixing events, from a young stage, where the core retains its vorticity and occupies most of the eddy, through a mature stage, where the eddy has a reduced inner core and a slowly revolving outer ring, to a decay stage, where the vorticity maximum is substantially reducedThis work has been supported by the Spanish government through projects FRENTES (AMB95-0731), COCA (REN2000-1471-C02-02MAR), and BREDDIES (REN2001-2650/ANT) and the special action MAR1999-1489-E and by the European Union through projects CANIGO (MAS3-CT96-0060) and OASIS (EVK3-CT-2002-00073-OASIS)Peer Reviewe
- …