Variabilidade e tendencias interanuais no fitoplancto mariño das costas de Galicia

13 páginas, 2 tablas, 7 figuras[EN] The available information on phytoplankton biomass and species composition in Galician waters was studied to find out their spatial variability as well as the annual trends. The areas covered included the oceanic zone, the shelf and the inner part of the Rías. In general a significant drop in diatoms was observed. The series also indicated an increase in dinoflagellates, although it was not statistically significant. The diatom species related to blooms in the area declined, whereas those indicative of weak upwelling or stratificacion showed an increase. Even though not all trends were significant, the available data are consistent with the decrease in upwelling intensity over the last 40 years. The results also suggest that effects of climate changes on phytoplankton may be delayed for several years. In any case, the large oceanographic variability of the region, along with the lack of continuity of some o[GA] Co obxecto de coñecer a variabilidade espacial e as tendencias interanuais do fitoplancto galego, estudáronse as series de datos históricos dispoñibles para Galicia, abarcando desde a zona oceánica ata as zonas máis costeiras das rías e a plataforma continental. En xeral, observouse unha diminución significativa das diatomeas, especialmente na zona oceánica. Tamén hai indicios dun incremento, aínda que non significativo, dos dinoflaxelados. O descenso das diatomeas foi debido á caída das abundancias de especies propias de floracións, tanto primaverais como estivais asociadas ao afloramento. Así mesmo, aumentaron as especies de diatomeas propias de afloramentos febles ou estratificación. Malia que non todas as tendencias foron significativas, os resultados son coherentes cunha diminución da intensidade do afloramento nos últimos 40 anos e un cambio nas condicións climáticas desde a década de 1980. Os resultados indican que os efectos dos cambios climáticos sobre o fitoplancto se poden manifestar con varios anos de retardo. Con todo, a alta variabilidade oceanográfica da zona, especialmente de alta frecuencia, e mais a falta de continuidade de moitas series de datos dificultan o establecemento de relacións claras entre cambios ambientais e o fitoplanctoEsta análise das tendencias do fitoplancto en Galicia foi financiada parcialmente pola Consellería de Medio Ambiente e Desenvolvemento Sostible (Programa CLIGAL) e polo proxecto REFORZA (PGIDT06RMA60401PR) da Consellería de Innovación e Industria da Xunta de Galicia. O traballo de María Huete-Ortega estivo financiado polo Programa Predoutoral de Formación de Profesorado Universitario do Ministerio de Educación y Ciencia.Peer reviewe

Heart rate and blood pressure in mitral valve prolapse patients : divergent effects of long-term propranolol therapy. Correlations with catecholamines

Copyright © 2007 Published by Elsevier Inc.Introduction: There is a well-known association between mitral valve prolapse (MVP) and low blood pressure (BP), although patients (P) often have high levels of catecholamines (CAT) and high heart rate (HR). To our knowledge, there are no studies about the effects of long-term adrenergic b-blockade on these parameters. Methods: Twenty normal individuals (N)—8 males (M) (49.9 F 12.9 years) and 12 females (F) (41.8 F 11.8 years); 46 MVP P—15 M (49.3 F 15.5 years) and 31 F (42.0 F 12.8 years). Phase1—in both N and P free of medication, determination of (1) 24H urinary epinephrine (E) and norepinephrine (NE) by HPLC; (2) rest HR by ECG; (3) 24H ambulatory HR and BP (ABM). Phase2—same tests in MVP P while taking propranolol by 10 to 12 months. Results: CAT ng/mg creatinine: E—M 5.1 F 2.5 (N), 9.1 F 3.9 (Ph1), 7.9 F 3.1 (Ph2); F 6.2 F 3.5 (N), 13.0 F 9.7 (Ph1), 10.7 F 6.7 (Ph2). Higher in P ( P b .01), lower under propranolol ( P = .002). NE—M 22.2 F 7.2 (N), 36.8 F 16.8 (Ph1), 27.4 F 10.6 (Ph2); F 28.1 F 7.3 (N), 46.2 F 18.1 (Ph1), 33.0 F 12.9 (Ph2). Higher in P ( P b .01), lower under propranolol ( P b .001). HR—M 75 F 5.4 (N), 79 F 7.2 (Ph1), 65 F 3.8 (Ph2); F 74 F 3.2 (N), 80 F 6.5 (Ph1), 69 F 6.2 (Ph2). Lower under propranolol ( P b .0001). ABM: phase1—HR higher in P. SBP and DBP lower in P. Phase2—lower HR whereas higher SBP and DBP in P under propranolol. No correlation between BP and CAT. Correlation between E levels and rest HR. Conclusions: These MVP patients had high levels of CAT, high HR, and low BP. With long-term b-blockade, HR decreased related to E, but BP raised, supporting the role of b2 receptors supercoupling on low BP in MVP.info:eu-repo/semantics/publishedVersio

Heart rate and blood pressure in mitral valve prolapse patients : divergent effects of long-term propranolol therapy and correlations with catecholamines

Copyright © 2007 The Anatolian Journal of Cardiology.Objective: There is a well known association between mitral valve prolapse (MVP) and low blood pressure (BP), although patients often have high levels of catecholamines and high heart rate (HR). The main objective of our study was to evaluate the effects of long-term adrenergic beta-blockade on these parameters. Methods: The study population consisted of 46 patients with MVP and the control group consisted of 20 normal individuals. The study had two phases: in the first phase, patients were free of medications. In the second phase, patients were under treatment with propranolol for 10 to 12 months. The tests were performed in normal individuals and patients in the first phase. Only patients underwent the same tests in the second phase. Measurement of urinary epinephrine and norepinephrine levels, by high performance liquid chromatography, was done. Rest HR was determined by electrocardiogram (ECG), and ambulatory blood pressure and HR were evaluated by 24 hours ambulatory blood pressure monitoring (ABPM) using the auscultatory method. Results: The levels of epinephrine and norepinephrine were significantly higher in patients than in normal controls and decreased under propranolol. Rest and ambulatory HR were higher in patients and decreased under propranolol. The 24 hours systolic and diastolic BPs were lower in patients, and their values increased under propranolol. Heart rate decreasing and epinephrine levels reduction were positively correlated. No correlation was found between BP increase and catecholamine levels. Conclusion: The study results show divergent effects of propranolol on blood pressure, which increased, and on heart rate, that decreased, in patients with MVP. Heart rate decrease was an expected result and depends, namely, on b1 receptors blockade. Increase in BP is an unusual response to adrenergic beta-blockade in normal conditions, and this finding supports the preponderance of b2 receptors on the BP control in patients with MVP.info:eu-repo/semantics/publishedVersio

Hydrological structures along the N y NW Iberian Shelf during the winter-spring transition

ECOPE

Epitaxial growth of SrTiO3 films on cube-textured Cu-clad substrates by PLD at low temperature under reducing atmosphere

The growth of epitaxial {001} SrTiO3 (STO) on low-cost cube-textured Cu-based clad substrate at low temperature was carried out by means of pulsed laser deposition (PLD). STO film was deposited in one step under a reducing atmosphere (5% H2 and 95% Ar mixture) to prevent the oxidation of the metal surface. The optimization of PLD parameters leads to a sharpest biaxial texture at a temperature as low as 500 °C and a thickness of 500 nm with a (100) STO layer. The upper limit of highly textured STO thickness was also investigated. The maximum thickness which retains the best quality {001} texture is 800 nm, since the texture is preserved not only through the layer but also on the surface. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) measurements showed that STO films are continuous, dense, and smooth with very low roughness (between 5 and 7 nm). This paper describes the development of STO layer by means of PLD in absence of oxygen throughout the process, suggesting an alternative and effective method for growing highly {001} textured STO layer on low-cost metal substrates

The use of clinical guidelines for referral of patients with lesions suspicious for oral cancer may ease early diagnosis and improve education of healthcare professionals

Early diagnosis and referral of oral cancer is essential. Successful implementation of clinical guidelines must include current practitioners and students. Objective: To evaluate the diagnostic accuracy of students at oral cancer screening and to assess the effectiveness of clinical referral guidelines. Study Design: Fifth year dental students were randomly allocated to either control (n=19) or experimental groups (n=18). Both received the customary training in oral diagnosis. The experimental group underwent a 2 hour workshop where the guidelines for the referral of suspicious lesions were discussed. Three months later, a set of 51 clinical cases including benign, malignant, and precancerous conditions/lesions were used to assess the screening ability of each subject. Results: All 37 students entered the study. Sensitivity (control group) ranged from 16.7% to 66.7%; the experimental group scored from 16.7% to 83.3%. Fifty percent of the experimental students reached sensitivity values ?62.5% (p=0.01). Diagnostic specificity (control group) spanned from 80% to 93.3% (median=50%); amongst experimental group it ranged from 82.2% to 97.8% (median=92.8%); (p=0.003). Concordance -control group- was X=82.5 (SD=3.2), and X=88.2 (SD=4.3) for the experimental, (p>0.001). Cohen's kappa test was poor (K<0.40) for the controls and moderate for the experimental group. The experimental group referred more oral cancers urgently (p=0.002) and left less unreferred cancers (0.04). This group also referred more precancerous lesions/conditions urgently (p=0.02). Conclusions: The implementation of a clinical referral guideline at undergraduate level has proved valuable, under experimental conditions, to significantly increase diagnostic abilities of the examiners and thus to improve screening for oral cancer. © Medicina Oral S. L

Survival of spin state in magnetic porphyrins contacted by graphene nanoribbons

We report on the construction and magnetic characterization of a fully functional hybrid molecular system composed of a single magnetic porphyrin molecule bonded to graphene nanoribbons with atomically precise contacts. We use on-surface synthesis to direct the hybrid creation by combining two molecular precursors on a gold surface. High-resolution imaging with a scanning tunneling microscope finds that the porphyrin core fuses into the graphene nanoribbons through the formation of new carbon rings at chemically predefined positions. These ensure the stability of the hybrid and the extension of the conjugated character of the ribbon into the molecule. By means of inelastic tunneling spectroscopy, we prove the survival of the magnetic functionality of the contacted porphyrin. The molecular spin appears unaffected by the graphenoid electrodes, and we simply observe that the magnetic anisotropy appears modified depending on the precise structure of the contacts.We acknowledge the financial support from Spanish Agencia Estatal de Investigación (AEI) (project nos. MAT2016-78293-C6 and FIS2015-62538-ERC, and the Maria de Maeztu Units of Excellence Programme MDM-2016-0618), the Basque Government (Department Industry, grant no. PI-2015-1-42), the European project PAMS (610446), the Xunta de Galicia (Centro singular de investigación de Galicia accreditation 2016 to 2019, ED431G/09), the European Research Council (grant agreement no. 635919), and the European Regional Development FundS

Estimación del nivel de habilidad en sistemas tutores inteligentes utilizando una metodología multiatributo

Para el funcionamiento ideal de un sistema tutor inteligente es indispensable poder estimar el nivel de habilidad de los estudiantes de acuerdo a objetivos complejos de aprendizaje. En este trabajo se propone una arquitectura para la evaluación del nivel de habilidad del estudiante, basada en la teoría de la utilidad multiatributo, utilizando como operador de agregación a la integral de Choquet. El método toma en cuenta los objetivos de aprendizaje planteados por el tomador de decisiones (académicos, representantes instituciones, etc.) representados por relaciones complejas que se pueden dar entre los criterios considerados para la evaluación.XVI Workshop Tecnología Informática Aplicada en Educación (WTIAE).Red de Universidades con Carreras en Informática (RedUNCI

Comportamiento termomecánico de un acero microaleado al Nb-V

Empleando ensayos de compresión simple en ca- liente y relajación de tensiones después de la de - formación en un dilatómetro modelo DIL805T, se obtuvieron las curvas de fluencia y relajación de dos aceros, el primero de ellos al C – Mn y otro HS- LA con idéntica composición química base, micro- aleado con Nb – V. Los ensayos de compresión simple fueron efectua- dos a temperaturas en el rango austenítico, desde 900 – 1.200 ºC y velocidades de deformación de 0.001, 0.01, 0.1, 1 y 10 s - 1 . Se obtuvieron las curvas de fluencia para las diferentes condiciones, permitien- do el estudio del efecto de los elementos microale- antes sobre la recristalización dinámica y la micro- estructura final; pudiendo comprobar mediante un análisis microestructural el efecto retardador en la cinética de recristalización que presenta el acero microaleado, el incremento en la deformación críti- ca y en la energía de activación. Se determina asi- mismo por medio del método de relajación de ten - siones la cinética de precipitación, elaborando los diagramas precipitación – temperatura – tiempoPostprint (published version