30 research outputs found

    Solución de múltiples sistemas lineales en GPUs

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    Este trabajo se centra en el calculo, de forma concurrente, de múltiples sistemas lineales definidos por matrices densas de una dimensión media. Se considera una solución basada en la factorización de Cholesky y su implementación sobre plataformas GPUs. Este tipo de problema algebraico forma parte de distintos modelos de procesamiento de señal, y además exhibe distintos niveles de paralelismo que pueden ser explotados muy eficientemente por las GPUs. En este trabajo, como aplicación del problema, nos centramos en la detección de anomalías sobre imágenes hiperespectrales, lo que supone una importante tarea en la explotación de este tipo de imágenes obtenidas en la observación de la Tierra. Concretamente, consideramos la versión local del ampliamente usado algoritmo RX (Reed-Xiaoli), denotado como LRX, en el que una de sus etapas más costosas consiste en la solución, para cada pixel de la imagen, de un sistema lineal cuyas dimensiones coinciden con el número de bandas de la imagen. En este contexto se describe y evalúa la solución múltiple de sistemas lineales en GPUs, y se comprueba el factor de aceleración obtenido con la implementación propuesta en este trabajo.Este trabajo ha sido financiado por el Ministerio de Economía y Competitividad (TIN2008- 01117, TIN2011-23283, TIN2012-37483-C03-01 and AYA2011-29334-C02-02), Junta de Andalucía (P10- TIC-6002 y P011-TIC7176), Junta de Extremadura (PRI09A110 y GR10035), CAPAP-H4 (TIN2011- 15734-E) y por los fondos FEDER. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Conocimiento didáctico de maestros en formación sobre objetivos de aprendizaje

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    El proceso de formación de los maestros incluye la familiarización con objetivos específicos de aprendizaje, puesto que su empleo forma parte de la futura labor profesional. Identificar qué objetivos se pueden planificar con una tarea matemática escolar pertenece al ámbito del conocimiento didáctico. En esta comunicación describimos cómo expresan los estudiantes del grado de Educación Primaria de último curso objetivos a partir de una tarea matemática escolar. Los resultados muestran diferencias en las capacidades identificadas, el nivel cognitivo de los contenidos mencionados y la ausencia de consideración de contextos

    Renal transplantation in the modern immunosuppressive era in Spain: four-year results from a multicenter database focus on post-transplant cardiovascular disease

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    Producción CientíficaTo evaluate cardiovascular disease (CVD) after renal transplantation we established a CVD database (no-intervention) including all patients transplanted among 2000–2002 in 14 hospitals from Spain (Renal Forum Group) (n¼2600). They were prospective followed annually thereafter and we present herein the most important results concerning survival figures and CVD at four years. Mean recipient age was 49.7±13.7 years: 16% retransplanted and 12.5% hyperimmunized. Tacrolimus, mycophenolate mofetil, and steroids was used in 63%. Acute rejection (AR) rate at 1 year was 14.8%. Graft and patient survival at 48 months were 85.6% (death censored) and 91.7% respectively. The first cause of graft loss was vascular in the first year, death with function during the 2–3 years, and chronic allograft nephropathy at the 4th year. Donor age, time on dialysis, acute tubular necrosis (ATN), AR, SCr at 6 months, the use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers in the first year, and systolic blood pressure at 24 months were independent risk factors for graft loss at 4th year. The first cause of death was CVD (predominantly ischemic heart disease (IHD) in the first year). Recipient age, ATN, and SCr at 6 months were independent predictors of mortality. Despite worsening of donor age, comorbidity, and advanced age of recipients, survival figures at four years are considered good in our Spanish non-selected population. Cardiovascular mortality is the most important cause of death and graft loss particularly, IHD in the first year. Therefore, to decrease post-transplant mortality a careful cardiovascular evaluation and treatment in the waiting list and a close follow-up of patients after transplantation is mandatory

    Ultrasmall manganese ferrites for in vivo catalase mimicking activity and multimodal bioimaging

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    Manganese ferrite nanoparticles display interesting features in bioimaging and catalytic therapies. They have been recently used in theranostics as contrast agents in magnetic resonance imaging (MRI), and as catalase-mimicking nanozymes for hypoxia alleviation. These promising applications encourage the development of novel synthetic procedures to enhance the bioimaging and catalytic properties of these nanomaterials simultaneously. Herein, a cost-efficient synthetic microwave method is developed to manufacture ultrasmall manganese ferrite nanoparticles as advanced multimodal contrast agents in MRI and positron emission tomography (PET), and improved nanozymes. Such a synthetic method allows doping ferrites with Mn in a wide stoichiometric range (MnxFe3-xO4, 0.1 ≤ x ≤ 2.4), affording a library of nanoparticles with different magnetic relaxivities and catalytic properties. These tuned magnetic properties give rise to either positive or dual-mode MRI contrast agents. On the other hand, higher levels of Mn doping enhance the catalytic efficiency of the resulting nanozymes. Finally, through their intracellular catalase-mimicking activity, these ultrasmall manganese ferrite nanoparticles induce an unprecedented tumor growth inhibition in a breast cancer murine model. All of these results show the robust characteristics of these nanoparticles for nanobiotechnological applications.The authors thank M. Jeannin from Lasie Laboratory (La Rochelle University) for the Raman studies. S.C.R. is supported by the grant PID2019-106139RA-100 funded by MCIN. J.R.-C. is supported by grants from the Ministerio de Economía, Industria y Competitividad (MEIC) (SAF2017-84494-C2-R). J.R.C. received funding from the BBVA Foundation (PR [18]_BIO_IMG_0008) and La Caixa (HR18-00052). Y.F.-A. received funding from the Santander-Universidad Zaragoza Fellowship program. L.G. acknowledges financial support from the Ramón y Cajal program (RYC-2014-15512). CIC biomaGUNE is supported by the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (MDM-2017-0720). The authors acknowledge the use of Servicio General de Apoyo a la Investigación-SAI, Universidad de Zaragoza. H.G. is supported by the Ligue contre le Cancer (CD16, CD17) and Région Nouvelle Aquitaine (Projet “Nanovect”). J.A.E. is supported by RTI2018-099357-B-I00, HFSP (RGP0016/2018), CIBERFES16/10/00282 and RED2018-102576-T. The CNIC is supported by the Pro-CNIC Foundation and by the Severo Ochoa of Excellence Program.Peer reviewe

    Clinical guide of the Spanish Society of Nephrology on the prevention and treatment of peritoneal infection in peritoneal dialysis

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    [Resumen] Las infecciones peritoneales siguen constituyendo una complicación muy relevante de la diálisis peritoneal, por su incidencia todavía elevada y por sus importantes consecuencias clínicas, en términos de mortalidad, fracaso de la técnica y costes para el sistema sanitario. Las prácticas de prevención y tratamiento de esta complicación muestran una notable heterogeneidad derivada, entre otros factores, de la complejidad del problema y de la escasez de evidencia clínica que permitan responder de manera clara a muchas de las dudas planteadas. El propósito de este documento es proporcionar una revisión completa y actualizada de los métodos de diagnóstico, prevención y tratamiento de estas infecciones. El documento se ha elaborado tomando como referencia de partida la guía más reciente de la Sociedad Internacional de Diálisis Peritoneal (2016). Mientras que para el capítulo diagnóstico se ha adoptado una estructura más narrativa, el análisis de las medidas de prevención y tratamiento ha seguido una metodología sistemática (Grading of Recommendations, Assessment, Development and Evaluation [GRADE]), que especifica el nivel de evidencia y la fuerza de las sugerencias y recomendaciones propuestas, y facilita actualizaciones futuras de la guía. La gran extensión y numerosas recomendaciones o sugerencias emanadas de la revisión ponen de manifiesto la complejidad y gran número de facetas a tener en cuenta para un adecuado abordaje de esta importante complicación de la diálisis peritoneal.[Abstract] Peritoneal infections still represent a most feared complication of chronic peritoneal dialysis, due to their high incidence and relevant clinical consequences, including direct mortality, technique failure and a significant burden for the health system. The practices for prevention and treatment of this complication show a remarkable heterogeneity emerging, among other factors, from the complexity of the problem and from a paucity of quality evidence which could permit to respond clearly to many of the raised questions. The purpose of this document is to provide a complete and updated review of the main methods of diagnosis, prevention and treatment of these infections. The document has been elaborated taking as a reference the most recent guidelines of the International Society of Peritoneal Dialysis (2016). The diagnostic considerations are presented in a narrative style while, for prevention and therapy, we have used a systematic methodology (Grading of Recommendations, Assessment, Development and Evaluation [GRADE]), which specifies the level of evidence and the strength of the proposed suggestions and recommendations and facilitates future updates of the document. The length of the document and the many suggestions and recommendations coming out of the review underline the large number and the complexity of the factors to be taken into consideration for an adequate approach to this complication of peritoneal dialysis

    Canagliflozin and renal outcomes in type 2 diabetes and nephropathy

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    BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to <90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], >300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years

    The 13th Southern Hemisphere Conference on the Teaching and Learning of Undergraduate Mathematics and Statistics

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    Ngā mihi aroha ki ngā tangata katoa and warm greetings to you all. Welcome to Herenga Delta 2021, the Thirteenth Southern Hemisphere Conference on the Teaching and Learning of Undergraduate Mathematics and Statistics. It has been ten years since the Volcanic Delta Conference in Rotorua, and we are excited to have the Delta community return to Aotearoa New Zealand, if not in person, then by virtual means. Although the limits imposed by the pandemic mean that most of this year’s 2021 participants are unable to set foot in Tāmaki Makaurau Auckland, this has certainly not stopped interest in this event. Participants have been invited to draw on the concept of herenga, in Te Reo Māori usually a mooring place where people from afar come to share their knowledge and experiences. Although many of the participants are still some distance away, the submissions that have been sent in will continue to stimulate discussion on mathematics and statistics undergraduate education in the Delta tradition. The conference invited papers, abstracts and posters, working within the initial themes of Values and Variables. The range of submissions is diverse, and will provide participants with many opportunities to engage, discuss, and network with colleagues across the Delta community. The publications for this thirteenth Delta Conference include publications in the International Journal of Mathematical Education in Science and Technology, iJMEST, (available at https://www.tandfonline.com/journals/tmes20/collections/Herenga-Delta-2021), the Conference Proceedings, and the Programme (which has created some interesting challenges around time-zones), by the Local Organizing Committee. Papers in the iJMEST issue and the Proceedings were peer reviewed by at least two reviewers per paper. Of the ten submissions to the Proceedings, three were accepted. We are pleased to now be at the business end of the conference and hope that this event will carry on the special atmosphere of the many Deltas which have preceded this one. We hope that you will enjoy this conference, the virtual and social experiences that accompany it, and take the opportunity to contribute to further enhancing mathematics and statistics undergraduate education. Ngā manaakitanga, Phil Kane (The University of Auckland | Waipapa Taumata Rau) on behalf of the Local Organising Committ

    Abstracts from the Food Allergy and Anaphylaxis Meeting 2016

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    Innovación curricular con un enfoque STEM y el uso de Realidad Virtual Inmersiva

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    I Congreso Internacional de Tecnologías Emergentes en Educación, Granada (España), del 15 al 17 de mayo 2019Se presenta una experiencia didáctica que incorpora Realidad Virtual Inmersiva (RVI) a la enseñanza de las Ciencias y Matemáticas, cuyo objetivo es mejorar la actitud hacia el aprendizaje de la dimensión científico-matemáticaDepartamento de Didáctica de las Ciencias Experimentales (Universidad de Granada); Grupo de Investigación HUM613 (Didáctica de las Ciencias Experimentales y de la Sostenibilidad); Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR); Departamento de Didáctica de las Matemáticas (Universidad de Granada
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