76 research outputs found

    Modelling diffusion of innovations in a social network

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    A new simple model of diffusion of innovations in a social network with upgrading costs is introduced. Agents are characterized by a single real variable, their technological level. According to local information agents decide whether to upgrade their level or not balancing their possible benefit with the upgrading cost. A critical point where technological avalanches display a power-law behavior is also found. This critical point is characterized by a macroscopic observable that turns out to optimize technological growth in the stationary state. Analytical results supporting our findings are found for the globally coupled case.Comment: 4 pages, 5 figures. Final version accepted in PR

    Synchronization, Diversity, and Topology of Networks of Integrate and Fire Oscillators

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    We study synchronization dynamics of a population of pulse-coupled oscillators. In particular, we focus our attention in the interplay between networks topological disorder and its synchronization features. Firstly, we analyze synchronization time TT in random networks, and find a scaling law which relates TT to networks connectivity. Then, we carry on comparing synchronization time for several other topological configurations, characterized by a different degree of randomness. The analysis shows that regular lattices perform better than any other disordered network. The fact can be understood by considering the variability in the number of links between two adjacent neighbors. This phenomenon is equivalent to have a non-random topology with a distribution of interactions and it can be removed by an adequate local normalization of the couplings.Comment: 6 pages, 8 figures, LaTeX 209, uses RevTe

    CONOCIMIENTOS QUE TIENEN LOS ALUMNOS DE ENFERMERÍA DE LA HIPERTENSIÓN ARTERIAL.

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    Introduction: Knowledge about hypertension among nurses is a subject of great concern due to their important role in prevention, health education, control and follow-up of hypertensive patients. As hypertension is a prevalent health condition in western societies, the goal of this work is to assess the level of knowledge about high blood pressure in a sample of nursing students, as future professionals of this discipline. The results will help us to improve their formation and their lifestyle habits. Methods: Descriptive study. Variables were analysed using Chi-square tests, complemented with residual analysis.Los conocimientos que sobre la hipertensión arterial pueden tener las enfermeras en el desarrollo de su actividad profesional tienen una gran importancia, dada su responsabilidad en este campo, tanto en la prevención de los factores de riesgo, realizando educación sanitaria, como en el control de la presión arterial y en los cuidados, cuando se producen complicaciones. En este trabajo pretendemos profundizar en los conocimientos de los alumnos de enfermería, como futuros profesionales, en un tema tan frecuente en las sociedades desarrolladas como es la hipertensión arterial, para así poder mejorar su formación y sus hábitos de vida no siempre saludables. El objetivo de este trabajo es profundizar en los conocimientos que sobre la hipertensión arterial tienen los alumnos de la Escuela de Enfermería de la Universidad de Murcia. Material y método: se realizó un estudio descriptivo de las variables y los análisis estadísticos correspondientes de X2 de Pearson, complementado con un análisis de residuos

    Response of the photosynthetic apparatus to a flowering-inductive period by water stress in Citrus

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    The photosynthetic responses to a flowering-inductive water-stress period and recovery were studied and compared in two Citrus species. Under greenhouse conditions, Fino lemon and Owari satsuma trees were subjected to moderate (-2 MPa at predawn) and severe (-3 MPa) water stress levels and were re-watered after 60 days. Vegetative growth was inhibited during the stress assays, and strong defoliation levels were reported, especially in Fino lemon. In both species, bud sprouting was induced after re-watering. Flowers and vegetative shoots developed in Owari satsuma after a drought period, and the development was independent of the stress level. In Fino lemon, vegetative shoots and flowers were primarily formed after moderate and severe stress, respectively. The photosynthetic rate and stomatal conductance were reduced by water stress, and a marked increase in water-use efficiency at the moderate water deficit level was observed. Nevertheless, the photosynthetic apparatus was not damaged, since the maximum quantum yield, photosynthetic pigment concentrations and Rubisco level and activity did not change. Furthermore, the measured malonyldialdehyde (MDA) and peroxidase activity indicated that oxidative stress was not specifically triggered by water stress in our study. Therefore, the gas exchange, fluorescence and biochemical parameters suggested that diffusional limitations to photosynthesis predominated in both of the studied Citrus species, and explained the rapid recovery of the photosynthetic parameters after rehydration. The net CO 2 fixation rate and stomatal conductance were recovered within 24 h in Fino lemon, whereas 3 days were required in Owari satsuma. This suggests the presence of some metabolic limitations in the latter species. Furthermore, the sensibility of the defoliation rates, the accumulation of proline and the stomatal behaviour in response to water stress indicated a higher drought tolerance of Fino lemon, according to its better acclimation to hot climates. © 2011 Springer-Verlag.The authors thank Dr. J. Moreno and co-workers from the Departamento de Bioquimica of the Universidad de Valencia for his help and support in the Rubisco assays, and Dr. F. Fornes, Dr. A. Calatayud and Dr. E. Primo-Millo for the critical review of the manuscript. This work was funded by the Universitat Politecnica de Valencia, Spain (Ayudas para primeros proyectos de investigacion PAID06-06).Ávila Reséndiz, C.; Guardiola Barcena, JL.; González Nebauer, S. (2012). Response of the photosynthetic apparatus to a flowering-inductive period by water stress in Citrus. Trees - Structure and Function. 26(3):833-840. https://doi.org/10.1007/s00468-011-0657-4S833840263Addicott FT (1982) Abscission. 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Physiol Plant 86:648–652García-Sánchez F, Syvertsen JP, Gimeno V, Botía P, Pérez-Pérez JG (2007) Responses to flooding and drought stress by two citrus rootstock seedlings with different water-use efficiency. Physiol Plant 130:532–542Genty B, Briantais JM, Baker NR (1989) The relationship between quantum yield of photosynthetic electron transport and quenching of chlorophyll fluorescence. Biochim Biophys Acta 990:87–92Gómez-Cadenas A, Tadeo FR, Talon M, Primo-Millo E (1996) Leaf abscission induced by ethylene in water-stressed intact seedlings of Cleopatra mandarin requires previous abscisic acid accumulation in roots. Plant Physiol 112:401–408Gordo O, Sanz JJ (2010) Impact of climate change on plant phenology in Mediterranean ecosystems. Glob Chang Biol 16:1082–1106Heath RL, Packer L (1968) Photoperoxidation in isolated chloroplasts. I. Kinetics and stoichiometry of fatty acid peroxidation. 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    Effects of HCV Eradication on Bone mineral density in HIV/HCV Coinfected Patients

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    Little is known about the effects of eradication of HCV on bone mineral density (BMD) and biomarkers of bone remodeling in HIV/HCV coinfected patients. We prospectively assessed standardized BMD (sBMD) at the lumbar spine and femoral neck, World Health Organization (WHO) BMD categories at both sites, and plasma concentrations of soluble receptor activator of nuclear factor-kappaβ ligand (sRANKL), and osteoprotegerin (OPG) at baseline (the date of initiation of anti-HCV therapy) and at 96 weeks. A total of 238 patients were included, median age 49.5 years, 76.5% males, 48.3% with cirrhosis, 98.3% on antiretroviral therapy, median CD4+ cell count 527 cells/mm 3, 86.6% with HIV-1 RNA < 50 copies/mL. The prevalence of osteoporosis at baseline at the lumbar spine (LS) and femoral neck (FN) was 17.6% and 7.2%, respectively. Anti-HCV therapy comprised pegylated interferon and ribavirin (PegIFN-RBV) plus one direct-acting antiviral in 53.4%, PegIFN-RBV in 34.5%, and sofosbuvir/RBV in 12.2%. A total of 145 (60.9%) patients achieved sustained viral response (SVR). No significant effect of SVR was observed on sBMD for the interaction between time and SVR either in the LS (P=0.801) or the FN (P=0.911). Likewise, no significant effect of SVR was observed in plasma levels of sRANKL (P=0.205), OPG (P=0.249), and sRANKL/OPG ratio (P=0.123) for the interaction between time and SVR. No significant correlation was found between fibrosis by transient elastography, and LS and FN sBMD, at baseline, and week 96. SVR was not associated with significant changes in BMD nor biomarkers of bone remodeling in HIV/HCV-coinfected persons.This study was supported by Instituto de Salud Carlos III (ISCII), grant numbers PI11/01556, PI14/01094, PI14/01581, and PI14CIII/00011, and by Ministerio de Sanidad, Servicios Sociales e Igualdad, grant number EC11-241. The study was also funded by the RD16/0025/0017, RD16/0025/0018 and RD16CIII/0002/0002 projects as part of the Plan Nacional R + D + I and cofunded by ISCIII-Subdirección General de Evaluación and the Fondo Europeo de Desarrollo Regional (FEDER).S

    A home and ambulatory artificial nutrition (NADYA) group report, home parenteral nutrition in Spain, 2013

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    Aim: to communicate the results of the Spanish Home Parenteral Nutrition (HPN) registry of the NADYA-SENPE group for the year 2013. Material and methods: data was recorded online by NADYA group collaborators that were responsible of the HPN follow-up from 1st January to 31st December 2013. Results: a total of 197 patients and 202 episodes of HPN were registered from 35 hospitals that represents a rate of 4,22 patients/million habitants/year 2013. The median age was 53 years (IQR 40 – 64) for 189 adult patients and 7 months (IQR 6 – 35,5) for children. The most frequent disease in adults was neoplasm (30,7%) followed by other diseases (20,1%) and mesenteric ischemia (12,7%). Short bowel syndrome and intestinal obstruction (25,9%) were in 35.7% cases the indications for HPN

    Human immunodeficiency virus/hepatits C virus coinfection in Spain: Elimination is feasible, but the burden of residual cirrhosis will be significant

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    Background We assessed the prevalence of antibodies against hepatitis C virus (HCV-Abs) and active HCV infection in patients infected with human immunodeficiency virus (HIV) in Spain in 2016 and compared the results with those of similar studies performed in 2002, 2009, and 2015. Methods The study was performed in 43 centers during October-November 2016. The sample was estimated for an accuracy of 2% and selected by proportional allocation and simple random sampling. During 2016, criteria for therapy based on direct-acting antiviral agents (DAA) were at least significant liver fibrosis, severe extrahepatic manifestations of HCV, and high risk of HCV transmissibility. Results The reference population and the sample size were 38904 and 1588 patients, respectively. The prevalence of HCV-Abs in 2002, 2009, 2015, and 2016 was 60.8%, 50.2%, 37.7%, and 34.6%, respectively (P trend <.001, from 2002 to 2015). The prevalence of active HCV in 2002, 2009, 2015, and 2016 was 54.0%, 34.0%, 22.1%, and 11.7%, respectively (P trend <.001). The anti-HCV treatment uptake in 2002, 2009, 2015, and 2016 was 23.0%, 48.0%, 59.3%, and 74.7%, respectively (P trend <.001). In 2016, HCV-related cirrhosis was present in 7.6% of all HIV-infected individuals, 15.0% of patients with active HCV, and 31.5% of patients who cleared HCV after anti-HCV therapy. Conclusions Our findings suggest that with universal access to DAA-based therapy and continued efforts in prevention and screening, it will be possible to eliminate active HCV among HIV-infected individuals in Spain in the short term. However, the burden of HCV-related cirrhosis will continue to be significant among HIV-infected individuals

    Effect of Salmosan, a β-galactomannan-rich product on intestinal barrier function

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    Podeu consultar el III Workshop anual INSA-UB complet a: http://hdl.handle.net/2445/118993Sessió 2. Comunicació oral núm.

    Human Immunodeficiency Virus/Hepatits C Virus Coinfection in Spain: Elimination Is Feasible, but the Burden of Residual Cirrhosis Will Be Significant

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    Background: We assessed the prevalence of antibodies against hepatitis C virus (HCV-Abs) and active HCV infection in patients infected with human immunodeficiency virus (HIV) in Spain in 2016 and compared the results with those of similar studies performed in 2002, 2009, and 2015. Methods: The study was performed in 43 centers during October-November 2016. The sample was estimated for an accuracy of 2% and selected by proportional allocation and simple random sampling. During 2016, criteria for therapy based on direct-acting antiviral agents (DAA) were at least significant liver fibrosis, severe extrahepatic manifestations of HCV, and high risk of HCV transmissibility. Results: The reference population and the sample size were 38904 and 1588 patients, respectively. The prevalence of HCV-Abs in 2002, 2009, 2015, and 2016 was 60.8%, 50.2%, 37.7%, and 34.6%, respectively (P trend <.001, from 2002 to 2015). The prevalence of active HCV in 2002, 2009, 2015, and 2016 was 54.0%, 34.0%, 22.1%, and 11.7%, respectively (P trend <.001). The anti-HCV treatment uptake in 2002, 2009, 2015, and 2016 was 23.0%, 48.0%, 59.3%, and 74.7%, respectively (P trend <.001). In 2016, HCV-related cirrhosis was present in 7.6% of all HIV-infected individuals, 15.0% of patients with active HCV, and 31.5% of patients who cleared HCV after anti-HCV therapy. Conclusions: Our findings suggest that with universal access to DAA-based therapy and continued efforts in prevention and screening, it will be possible to eliminate active HCV among HIV-infected individuals in Spain in the short term. However, the burden of HCV-related cirrhosis will continue to be significant among HIV-infected individuals.This work was funded by grant Ref. no. GLD14-00279 from the GILEAD Fellowship Programme (Spain) and by the Spanish AIDS Research Network (RD16/0025/0017, RD16/0025/0018) that is included in the Spanish I+D+I Plan and is co-financed by ISCIII-Subdirección General de Evaluacion and European Funding for Regional Development (FEDER).S
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