Pólya's enumeration theorem (Spanish: El teorema de enumeración de Pólya)

We wish to offer here a didactic presentation, mainly based on G. Pólya’s original paper and by the light of various examples, of a topic of Combinatorics: Pólya’s (and Redfield’s) enumeration theorem. Our excuses for it just being that an oral version was exposed in one of the sessions corresponding to the year 1991 of the “Seminario Permanente de Actualización en Matemáticas de Logroño”, a meeting place for secondary teacher’s and university professors that as much owes to Chicho’s passion for Mathematics

Euler, Rey Pastor y la sumabilidad de series

Peer Reviewe

High-resolution scan of the Pyrenean crustal structure combining magnetotelluric and gravity data

The Pyrenees have undergone complex geodynamic evolution starting with experiencing significant tectonic events during the Variscan Orogeny, followed by the intrusion of large granitic complexes during the late Variscan stage, then the collision between the Iberian and European plates during the Alpine Orogeny, and finally, Mesozoic extension. Despite extensive studies and the application of various geophysical methods (two-dimensional seismic reflection data, gravity, and long period magnetotellurics) to investigate the Pyrenean structure, there are still fundamental questions regarding its basement and cover architecture. Specifically, the geometry at depth of significant bodies such as the Late Variscan intrusive granites and Triassic evaporitic accumulations, remains unclear. To better understand these issues, we have conducted joint magnetotelluric and gravity surveys along a 60-kilometer-long transect, spanning the boundary between the Axial and South Pyrenean Zones. Our final geological interpretation shows that the La Maladeta batholith consists of two distinct granitic bodies related to different intrusive pulses. In addition, we identify important Triassic evaporitic accumulations at depth. This work shows the high potential of integrating two geophysical models for understanding the geological evolution of structurally complex areas. The magnetotelluric and gravity data are complementary, with each dataset providing a different resolution for investigating the basement and cover architecture of the Pyrenees. These resolutions depend on the varied petrophysical properties of the rocks involved, including water content and deformation grade

pilotSTRATEGY project 2021-2026: “CO2 Geological Pilots in Strategic Territories”

[EN] The pilotSTRATEGY (2021-2026) is investigating geological CO2 storage sites in industrial regions to support development of large-scale carbon capture and storage (CCS). It is focused on deep saline aquifers–porous rock formations filled with brine several kilometres below ground – which promise a large capacity for storing captured CO2. The goal of the characterisation is to assess the site’s containment, injectivity, capacity, integrity, hydrodynamics, and monitorability in order to ensure safe and permanent storage of CO2. PilotSTRATEGY covers the initial stages of project development up to the pre-final investment decision (pre-FID), regulatory approval and permitting of storage, and applied on selected structures of Paris Basin in France, the Lusitanian Basin in Portugal and the Ebro Basin in Spain, and in lower detail, in West Macedonia in Greece and Upper Silesia in Poland.The project has received funding from the European Union’s Horizon 2020 programme (10.1 million Euros, No. 101022664).Peer reviewe

Trends in incidence, mortality and survival in women with breast cancer from 1985 to 2012 in Granada, Spain: a population-based study

The incidence of breast cancer has increased since the 1970s. Despite favorable trends in prognosis, the role of changes in clinical practice and the introduction of screening remain controversial. We examined breast cancer trends to shed light on their determinants Overall, age-adjusted (European Standard Population) incidence rates increased from 48.0 cases × 100,000 women in 1985–1989 to 83.4 in 2008–2012, with an annual percentage change (APC) of 2.5% (95%CI, 2.1–2.9) for 1985–2012. The greatest increase was in women younger than 40 years (APC 3.5, 95%CI, 2.4–4.8). For 2000–2012 the incidence trend increased only for stage I tumors (APC 3.8, 95%CI, 1.9–5.8). Overall age-adjusted breast cancer mortality decreased (APC − 1, 95%CI, − 1.4 – − 0.5), as did mortality in the 50–69 year age group (APC − 1.3, 95%CI, − 2.2 – − 0.4). Age-standardized net survival increased from 67.5% at 5 years in 1985–1989 to 83.7% in 2010–2012. All age groups younger than 70 years showed a similar evolution. Five-year net survival rates were 96.6% for patients with tumors diagnosed in stage I, 88.2% for stage II, 62.5% for stage III and 23.3% for stage IV. Breast cancer incidence is increasing – a reflection of the evolution of risk factors and increasing diagnostic pressure. After screening was introduced, the incidence of stage I tumors increased, with no decrease in the incidence of more advanced stages. Reductions were seen for overall mortality and mortality in the 50–69 year age group, but no changes were found after screening implementation. Survival trends have evolved favorably except for the 70–84 year age group and for metastatic tumors.This study was supported by a grant from the Acción Estratégica en Salud plan for the High Resolution Project on Prognosis and Care of Cancer Patients (No. AC14/00036) awarded by the Spanish Ministry of Economy and Competitiveness and co-funded by the European Regional Development Fund (ERDF)

The evolution of the ventilatory ratio is a prognostic factor in mechanically ventilated COVID-19 ARDS patients

Background: Mortality due to COVID-19 is high, especially in patients requiring mechanical ventilation. The purpose of the study is to investigate associations between mortality and variables measured during the first three days of mechanical ventilation in patients with COVID-19 intubated at ICU admission. Methods: Multicenter, observational, cohort study includes consecutive patients with COVID-19 admitted to 44 Spanish ICUs between February 25 and July 31, 2020, who required intubation at ICU admission and mechanical ventilation for more than three days. We collected demographic and clinical data prior to admission; information about clinical evolution at days 1 and 3 of mechanical ventilation; and outcomes. Results: Of the 2,095 patients with COVID-19 admitted to the ICU, 1,118 (53.3%) were intubated at day 1 and remained under mechanical ventilation at day three. From days 1 to 3, PaO2/FiO2 increased from 115.6 [80.0-171.2] to 180.0 [135.4-227.9] mmHg and the ventilatory ratio from 1.73 [1.33-2.25] to 1.96 [1.61-2.40]. In-hospital mortality was 38.7%. A higher increase between ICU admission and day 3 in the ventilatory ratio (OR 1.04 [CI 1.01-1.07], p = 0.030) and creatinine levels (OR 1.05 [CI 1.01-1.09], p = 0.005) and a lower increase in platelet counts (OR 0.96 [CI 0.93-1.00], p = 0.037) were independently associated with a higher risk of death. No association between mortality and the PaO2/FiO2 variation was observed (OR 0.99 [CI 0.95 to 1.02], p = 0.47). Conclusions: Higher ventilatory ratio and its increase at day 3 is associated with mortality in patients with COVID-19 receiving mechanical ventilation at ICU admission. No association was found in the PaO2/FiO2 variation

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

[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