Synthesis, characterization, bioactivity and biocompatibility of nanostructured materials based on the wollastonite-poly(ethylmethacrylate-co-vinylpyrrolidone) system

Composite materials are very promising biomaterials for hard tissue augmentation. The approach assayed in this work involves the manufacturing of a composite made of a bioactive ceramic, natural wollastonite (W) and a nanostructured copolymer of ethylmethacrylate (EMA) and vinylpyrrolidone (VP) to yield a bioresorbable and biocompatible VP–EMA copolymer. A bulk polymerization was induced thermally at 508C, using 1 wt % azobis(isobutyronitrile) (AIBN) as free-radical initiator. Structural characterization, compressive strength, flexural strength (FS), degradation, bioactivity, and biocompatibility were evaluated in specimens with a 60/40 VP/EMA ratio and ceramic content in the range 0–60%. A good integration between phases was achieved. Greater compression and FS, in comparison with the pure copolymer specimens was obtained only when the ceramic load got up to 60% of the total weight. The soaking in NaCl solution resulted in the initial swelling of the specimens tested. The maximum swelling was reached after 2–3 h of immersion and it was significantly greater for lower ceramic loads. This result makes the polymer component the main responsible for the interactions with the media. After soaking in SBF, microdomains segregation can be observed in the polymer component that can be related with a dramatic difference in the reactivity of both monomers in free radical polymerization, whereas the formation of an apatite-like layer on the W surfaces can be observed. Biocompatibility in vitro studies showed the absence of cytotoxicity of all formulations. The cells were able to adhere on the polystyrene negative control and on specimens containing 60 wt % wollastonite forming a monolayer and showing a normal morphology. However, a low cellular growth was observed. 2008 Wiley Periodicals, Inc. J Biomed Mater Res 88A: 53–64, 2009Peer reviewe

Modelos de gestión en nutrición clínica. Puntos débiles y puntos fuertes

En el VIº Foro de Debate Abbott-SENPE se establece una discusión multidisciplinar y multiprofesional para buscar el o los modelos de gestión clínica que consideramos más adecuados para la Unidades de Nutrición Clínica y Dietética (UNCyD) en España. Se valoran los puntos débiles y fuertes así como las oportunidades de los actuales sistemas y se concluye en la observación de una cierta disparidad vinculada no solo a las comunidades autónomas sino también a los diferentes tipos de hospital. Se propone, desde SENPE, la creación de un grupo de trabajo que ayude a la normalización de los modelos y a potenciar la cultura del Cuadro de Mandos Integral y de Gestión del Cambio.At the 6th Abbott-SENPE Debate Forum a multidisciplinary and multiprofessional discussion was established in order to seek for the model or the models of clinical management most appropriate for Clinical Nutrition and Dietetics Units (CNAD) in Spain. The weaknesses and strengths as well as opportunities for the current systems were assessed concluding that a certain degree of disparity was observed not only due to regional differences but also to different hospital types. It was proposed, from SENPE, the creation of a working group helping to standardize the models and promote the culture of Integral Control and Change Management

The upper Valanginian of the Oliva section (Prebetic Zone, Valencia): facies analysis, biostratigraphy, C-isotope stratigraphy and organic geochemistry

The Upper Valanginian stratigraphic section of the sierra de la Oliva (Prebetic, Valencia province) records a significant sedimentary episode which has been named as ”Weissert Event”.This event is characterized by a positive excursion in the δ13C profile, which have been considered to be linked to a global perturbation in the carbon cycle, with environmental consequences that have been the object of debate, especially the degree of oxygenation of the sea bottom waters.We studied the sedimentary evolution during the late Valanginian in a shallow platform setting, beginning with the drowning of the early Valanginian carbonate platform, followed by a succession of shallowing- upwards sequences, which define a general deepening-upward evolution. The δ13C profile records a positive excursion during the late Valanginian, and the biomarker study has revealed the episodic development of anoxia, coeval to the deposition of organic rich facies, occurred during the episode of maximum deepening of the platform.This study has demonstrated that the “Weissert Event” has been recorded in the Prebetic platform, and that the environmental perturbations gave place to the occasional development of anoxia in a context of high organic productivityLa sección estratigráfica del Valanginiense superior de la sierra de la Oliva (Prebético, provincia de Valencia) registra un interesante episodio sedimentario que ha sido denominado “Evento Weissert”. Este evento está caracterizado por una excursión positiva en los valores del δ13C, que se considera ligada a una perturbación global en el ciclo del carbono, cuyas consecuencias ambientales son objeto de discusión, especialmente las condiciones de oxigenación en los fondos marinos. El estudio presentado aquí muestra la evolución sedimentaria del Valanginiense superior en un ámbito de plataforma somera, que comienza con el drowning de la plataforma carbonatada del Valanginiense inferior, y continúa con una sucesión de secuencias de somerización, que en conjunto definen una evolución general de profundización. El perfil de δ13C registra una excursión positiva durante el Valanginiense superior, y el estudio de los biomarcadores ha puesto de manifiesto el desarrollo puntual de anoxia, simultáneo al depósito de facies ricas en materia orgánica, ocurrido en el momento de mayor profundización de la plataforma. Este estudio demuestra que el denominado “EventoWeissert” quedó reflejado en la plataforma Prebética, y que las perturbaciones ambientales locales dieron lugar al desarrollo puntual de anoxia en un contexto de elevada productividad orgánic

Low skeletal muscle mass assessed directly from the 3rd cervical vertebra can predict pharyngocutaneous fistula risk after total laryngectomy in the male population

Altres ajuts: Acord transformatiu CRUE-CSICAltres ajuts: Open Access Funding provided by Universitat Autonoma de Barcelona. European Regional Development Fund (A Way to Build Europe).Purpose: Skeletal muscle mass (SMM) loss and sarcopenia have been identified as risk factors for postoperative complications. The aim of this study was to investigate the relationship between pharyngocutaneous fistula (PCF) formation after total laryngectomy (TL) and SMM assessed from a computed tomography image of the 3rd cervical vertebra (C3). Methods: Retrospective study of 86 male patients who underwent TL between 2013 and 2019 in a single institution. We excluded women from the analysis due to our limited sample. SMM was determined from cross-sectional muscle area (CSMA) measurement at C3 using the ImageJ software. Results were compared with those for the skeletal muscle mass index (SMMI) calculated from the estimated measure at 3rd lumbar vertebra (L3). Results: PCF formation occurred in 21/86 patients. According to the CSMA at a C3 cut-off of 35.5cm2, of 18 patients (20.9%) with low SMM, 9 developed PCFs (50.0%). Among patients with normal SMM (n = 68, 79.1%), 12 developed PCFs (17.6%). The CSMA at C3 was the only variable significantly associated with PCF risk, which was 4.7 times greater in patients with low SMM (p = 0.007). Sarcopenia was more frequent in underweight patients (p = 0.0001), patients undergoing extended surgeries (p = 0.003), or presenting preoperative anaemia (p = 0.009) or hypoalbuminemia (p = 0.027). Conclusion: Measuring the CSMA at C3 obtained results equivalent to those obtained by calculating the SMMI at L3, suggesting that direct SMM assessment from C3 is a useful approach to evaluating PCF formation risk after TL

Central star formation and metallicity in CALIFA interacting galaxies

We use optical integral-field spectroscopic (IFS) data from 103 nearby galaxies at different stages of the merging event, from close pairs to merger remnants provided by the CALIFA survey, to study the impact of the interaction in the specific star formation and oxygen abundance on different galactic scales. To disentangle the effect of the interaction and merger from internal processes, we compared our results with a control sample of 80 non-interacting galaxies. We confirm the moderate enhancement (2-3 times) of specific star formation for interacting galaxies in central regions as reported by previous studies; however, the specific star formation is comparable when observed in extended regions. We find that control and interacting star-forming galaxies have similar oxygen abundances in their central regions, when normalized to their stellar masses. Oxygen abundances of these interacting galaxies seem to decrease compared to the control objects at the large aperture sizes measured in effective radius. Although the enhancement in central star formation and lower metallicities for interacting galaxies have been attributed to tidally induced inflows, our results suggest that other processes such as stellar feedback can contribute to the metal enrichment in interacting galaxies.Comment: 9 pages, 9 figures. Accepted for publication in Astronomy & Astrophysic

The effects of spatial resolution on Integral Field Spectrograph surveys at different redshifts. The CALIFA perspective

Over the past decade, 3D optical spectroscopy has become the preferred tool for understanding the properties of galaxies and is now increasingly used to carry out galaxy surveys. Low redshift surveys include SAURON, DiskMass, ATLAS3D, PINGS and VENGA. At redshifts above 0.7, surveys such as MASSIV, SINS, GLACE, and IMAGES have targeted the most luminous galaxies to study mainly their kinematic properties. The on-going CALIFA survey ($z\sim0.02$) is the first of a series of upcoming Integral Field Spectroscopy (IFS) surveys with large samples representative of the entire population of galaxies. Others include SAMI and MaNGA at lower redshift and the upcoming KMOS surveys at higher redshift. Given the importance of spatial scales in IFS surveys, the study of the effects of spatial resolution on the recovered parameters becomes important. We explore the capability of the CALIFA survey and a hypothetical higher redshift survey to reproduce the properties of a sample of objects observed with better spatial resolution at lower redshift. Using a sample of PINGS galaxies, we simulate observations at different redshifts. We then study the behaviour of different parameters as the spatial resolution degrades with increasing redshift.Comment: 20 pages, 16 figures. Accepted for publication in A&

Evolution of the Fundamental Plane of 0.2<z<1.2 Early-type galaxies in the EGS

The Fundamental Plane relates the structural properties of early-type galaxies such as its surface brightness and effective radius with its dynamics. The study of its evolution has therefore important implications for models of galaxy formation and evolution. This work aims to identify signs of evolution of early-type galaxies through the study of parameter correlations using a sample of 135 field galaxies extracted from the Extended Groth Strip in the redshift range 0.2<z<1.2. Using DEEP2 data, we calculate the internal velocity dispersions by extracting the stellar kinematics from absorption line spectra, using a maximum penalized likelihood approach. Morphology was determined through visual classification using the V+I images of ACS. The structural parameters of these galaxies were obtained by fitting de Vaucouleurs stellar profiles to the ACS I-band images, using the GALFIT code. S\'ersic and bulge-to-disc decomposition models were also fitted to our sample of galaxies, and we found a good agreement in the Fundamental Plane derived from the three models. Assuming that effective radii and velocity dispersions do not evolve with redshift, we have found a brightening of 0.68 mag in the B-band and 0.52 mag in the g-band at =0.7. However, the scatter in the FP is reduced by half when we allow the FP slope to evolve, suggesting a different evolution of early-type galaxies according to their intrinsic properties. The study of the Kormendy relation shows the existence of a population of very compact (Re<2 Kpc) and bright galaxies (-21.5>Mg>-22.5), of which there are only a small fraction (0.4%) at z=0. The evolution of these compact objects is mainly caused by an increase in size that could be explained by the action of dry minor mergers, and this population is responsible for the evolution detected in the Fundamental Plane.Comment: Accepted for publication in A&A. 12 pages, 10 Figures, and 1 online tabl

Advanced determination of piezoelectric properties of AlN thin films on silicon substrates

Piezoelectric deformations of thin, aluminum nitride (AlN) layers, on top of a silicon substrate, were studied by numerical calculations and interferometric measurements. Our calculation by finite element method demonstrates that substrate deformation under the top electrode may be comparable to the electric field induced deformation in the thin AlN layer, for a given applied voltage. Simulations also show the effect of a clamped or free substrate condition and the relative contributions of d33 and d31 piezoelectric constants. A Laser scanning vibrometry technique was used to measure deformations in the top surface with sub-picometer vertical resolution. By comparing calculations and experimental data, quantitative information about both d33 and d31 constants can be obtained

Effects of weight loss after bariatric surgery on pulmonary function tests and aobtructive sleep apnea in morbidly obese women

Introducción: la obesidad afecta a la función respiratoria e incrementa el riesgo de síndrome de apneas-hipopneas del sueño (SAHS). Objetivo: evaluar el efecto de la cirugía bariátrica, en mujeres con obesidad mórbida, sobre la función respiratoria y sobre el índice de apneas-hipopneas (IAH) tras dos años de seguimiento. Métodos: se incluyeron 15 mujeres (índice de masa corporal [IMC] medio 50,52 ± 12,71 kg.m-2, edad media 40,13 ± 10,06 años). Los enfermos fueron analizados en dos fases: previo a la cirugía bariátrica y tras dos años de la misma. En cada visita se valoraron las medidas antropométricas y se realizaron pruebas de función respiratoria consistentes en espirometría, pletismografía, medida de la presión inspiratoria máxima y del índice de tensión-tiempo de los músculos inspiratorios, así como análisis de gases arteriales. Por último, también se efectuó una poligrafía cardiorrespiratoria durante el sueño. Resultados: tras la cirugía bariátrica el IMC disminuyó en 44,07 kg.m-2 (IC 95% 38,32 – 49,81). De igual forma, se observaron incrementos significativos en el volumen espiratorio forzado al primer segundo (FEV1) (p < 0,01), la capacidad vital forzada (FVC) (p < 0,01), el volumen de reserva espiratorio (ERV) (p = 0,040), la capacidad funcional residual (FRC) (p = 0,009) y la resistencia de las vías aéreas (Raw) (p = 0,018). Por otra parte, el IAH (p = 0,001) y el índice de desaturación de oxígeno (p = 0,001) disminuyeron tras la cirugía. Se observó una correlación significativa entre el grado de pérdida de peso y el incremento del ERV (0,774, p = 0,024). Conclusiones: tras dos años desde la cirugía bariátrica se siguen observando mejorías significativas en la función respiratoria y en la gravedad del SAHS. La mejoría del ERV estaría en relación directa con los niveles de peso perdidoIntroduction: obesity impacts on respiratory function and also it acts as a risk factor for obstructive sleep apnea (OSA). Aims: to study the effects of bariatric surgery on pulmonary function tests and on OSA in morbidly obese women over 4 years. Methods: fifteen morbidly obese women (mean body mass index [BMI] 50.52 ± 12.71 kg.m-2, mean age 40.13 ± 10.06 years) underwent pulmonary function tests (PFT) in two opportunities (before and after weight loss surgery). PFT included spirometry, body plethysmography and measure of maximal inspiratory mouth pressure (PImax) and of tension-time index for inspiratory muscles. Also, in both opportunities, resting arterial blood gas tensions were evaluated and a full night sleep register was performed. Results: BMI significantly decreased after bariatric surgery (-44.07 kg.m-2 [CI 95% -38.32 – -49.81]). Also, there was a significantly increase in forced expiratory volume in 1 second (FEV1) (p < 0.01), forced vital capacity (FVC) (p < 0.01), expiratory reserve volume (ERV) (p = 0.040), functional residual capacity (FRC) (p = 0.009) and a decline in airways resistance (Raw) (p = 0.018). Concerning sleep registers, apnea hypopnea index (p = 0.001) and desaturation index (p = 0.001) were also reduced after weight loss. Improve in ERV had a significant correlation with weight loss (r = 0.774, p = 0.024). Conclussions: pulmonary function tests and apnea hypopnea index improve after bariatric surgery in mor- bidly obese women. Improvement of ERV is well correlated with weight los