Synthesis of Enantiopure Oxygen- and Nitrogen-Containing Heterocycles by Diastereoselective Ring-Closing Metathesis Reaction in Perhydro-1,3-benzoxazine Derivatives

Producción CientíficaDiastereoselective ring‐closing metathesis reactions on chiral trienic perhydro‐1,3‐benzoxazines derived from (−)‐8‐aminomenthol featuring two diastereotopic olefin chains is described. The diastereochemical outcome of the cyclization appeared to be dependent on the length and position of the olefin chains in perhydro‐1,3‐benzoxazine, the degree of substitution of the double bonds and the ruthenium catalyst used. After separation of the diastereomers, and removal of the chiral auxiliary, enantiopure oxygen‐ and nitrogen‐containing heterocycles were obtained.Ministerio de Economía, Industria y Competitividad (Project FEDER-CTQ2014-59870-P)Junta de Castilla y León (Ref. Project FEDER-VA115P17

Dimethylzinc-Mediated Addition of Phenylacetylene to α-Diketones Catalyzed by Chiral Perhydro-1,3-benzoxazines

Producción CientíficaAn efficient enantioselective Me2Zn-mediated mono addition of phenylacetylene to α-diketones in the presence of a chiral perhydro-1,3-benzoxazine ligand is described. At temperatures higher than -20 ºC a kinetic resolution of the resulting α-hydroxy ketone occurs which greatly improves the enantioselectivity although with moderate chemical yield. The alkynylation of nonsymmetrical aromatic diketones with electronically different substituents on the aromatic rings proceed with high regioselectivity. This procedure allows the preparation of α-hydroxy-α-ynyl-ketones as highly enantioenriched materials.2018-07-07Ministerio de Economía, Industria y Competitividad (Project CTQ2014-59870 P)Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA064U13

Predictive models for the characterization of internal defects in additive materials from active thermography sequences supported by machine learning methods

The present article addresses a generation of predictive models that assesses the thickness and length of internal defects in additive manufacturing materials. These modes use data from the application of active transient thermography numerical simulation. In this manner, the raised procedure is an ad-hoc hybrid method that integrates finite element simulation and machine learning models using different predictive feature sets and characteristics (i.e., regression, Gaussian regression, support vector machines, multilayer perceptron, and random forest). The performance results for each model were statistically analyzed, evaluated, and compared in terms of predictive performance, processing time, and outlier sensibility to facilitate the choice of a predictive method to obtain the thickness and length of an internal defect from thermographic monitoring. The best model to predictdefect thickness with six thermal features was interaction linear regression. To make predictive models for defect length and thickness, the best model was Gaussian process regression. However, models such as support vector machines also had significative advantages in terms of processing time and adequate performance for certain feature sets. In this way, the results showed that the predictive capability of some types of algorithms could allow for the detection and measurement of internal defects in materials produced by additive manufacturing using active thermography as a non-destructive test.This research was funded by Ministry of Science and Innovation, Government of Spain, through the research project titled Fusion of non-destructive technologies and numerical simulation methods for the inspection and monitoring of joints in new materials and additive manufacturing processes (FaTIMA) with code RTI2018-099850-B-I00. The authors are grateful to the Fundación Universidad de Salamanca for the indirect support provided by the ITACA proof-of-concept project (PC_TCUE_18-20_047), being this helpful for some of the purposes of this article

Architectural Apps for Smartphones: Four Finished Cases

This paper describes the process followed for the creation of four applications for iPhone/iPad devices, which have produced an unusual R&D and are applicable to professional practice. This process is born on two, apparently unconnected points: 1. University teaching, research and the professional practice of architecture should not be unconnected activities, but the complex reality of the world of construction means that they are seen as separate. 2. It is obvious that many technological tools such as PC tablets, smartphones... are being used by the general public in their everyday lives [1]. These are the first apps developed by the School of Architecture, where the formal and aesthetic requirements are of great importance, so the concept of a collection of apps also had to be resolved in these first apps. Hence, the seemingly simple user interface was complex to design, as it had to be the basis for future apps (yet to be designed at the time), either by the School of Architecture or other Faculties in the University

Monitoring and preliminary analysis of the natural responses recorded in a poorly accessible streambed spring located at a fluviokarstic gorge in Southern Spain

The analysis of natural responses (hydrodynamic, hydrothermal and hydrochemical) of karst springs is a well-established approach to provide insights into the hydrogeological functioning of the aquifers that they drain. However, a suitable monitoring program of these responses are often difficult to launch in poorly accessible streambed springs, due to the mixing between surface water and groundwater, in addition to topographic impediments. This work describes the installation procedure of the measurement equipment and the preliminary hydrogeological dataset collected at the Charco del Moro spring (Southern Spain) during one year. This outlet emerges 5 m below water surface, at the bottom of a partially flooded 20 - 200 m deep and 2 km long gorge, eroded by the Guadiaro River streamflow. It is considered the largest discharge point in the region, draining groundwater from northern nearby carbonate outcrops, although its catchment area is not established yet. Continuous (hourly) monitoring of electrical conductivity, water temperature, turbidity and water level (discharge) reflects a high degree of heterogeneity in the duality of groundwater flow and storage dynamics, which is typical of karst conduit flow systemsUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Enantioselective synthesis of 3-hydroxy- and 3-amino-3-alkynyl-2-oxindoles by the dimethylzinc-mediated addition of terminal alkynes to isatins and isatin-derived ketimines

Producción CientíficaA common protocol for enantioselective alkynylation of isatins and isatin-derived ketimines using terminal alkynes and Me2Zn in the presence of a catalytic amount of a chiral perhydro-1,3-benzoxazine with moderate to excellent enantioselectivity under mild reaction conditions is described. The additions to ketimines present a novel approach to chiral amines being derivatives of oxindoles. The reaction is broad in scope with respect to aryl- and alkyl-substituted terminal alkynes and isatin derivatives. In isatins, the alkynylation occurs at the Si face of the carbonyl group, whereas in the ketimine derivatives it occurs at the Re face of the imine.Junta de Castilla y León, proyectos FEDER-VA115P17 y VA149G1

Teaching-life Histories: An Analysis of Initial and Continuing Training for Twenty-first century Teachers

This research analyses the teaching practice of retired teachers with the objective of inquiring into the initial and continuing training that twenty-first century teachers need. To this end, a semistructured interview was conducted with an incidental, nonprobabilistic sample of 325 participants and performed quantitative analysis of the data with SPSS 23. The descriptive parameters were produced using frequency analysis. Contingency tables were produced to verify if sex or year of birth explained perceptions of the training required of to be a good teacher. The results revealed significant differences between those born before 1948 and those born after that year

Factores de riesgo de mortalidad en pacientes hospitalizados con COVID-19 aplicando un algoritmo de aprendizaje automático

Introduction Risk stratification of patients with COVID-19 can be fundamental to support clinical decision-making and optimize resources. The objective of our study is to identify among the routinely tested clinical and analytical parameters those that would allow us to determine patients with the highest risk of dying from COVID-19. Material and methods We carried out a retrospective cohort multicentric study by consecutively, including hospitalized patients with COVID-19 admitted in any of the 11 hospitals in the healthcare network of HM Hospitals-Spain. We collected the clinical, demographic, analytical, and radiological data from the patient's medical records. To assess each of the biomarkers’ predictive impact and measure the statistical significance of the variables involved in the analysis, we applied a random forest with a permutation method. We used the similarity measure induced by a previously classification model and adjusted the k-groups clustering algorithm based on the energy distance to stratify patients into a high and low-risk group. Finally, we adjusted two optimal classification trees to have a schematic representation of the cut-off points. Results We included 1246 patients (average age of 65.36 years, 62% males). During the study one hundred sixty-eight patients (13%) died. High values of age, D-Dimer, White Blood Cell, Na, CRP, and creatinine represent the factors that identify high-risk patients who would die. Conclusions Age seems to be the primary predictor of mortality in patients with SARS-CoV-2 infection, while the impact of acute phase reactants and blood cellularity is also highly relevant.S

Rhinosporidiosis in a dog from Uruguay and review of the literature

We report a case of nasal rhinosporidiosis in a dog native to Uruguay, being the sixth report of Rhinosporidium seeberi infection in this host from South America. Diagnosis was made by histopathology of biopsied tissue and specific PCR assay from nasal swab material. The patient was a 3-year-old male dog, of the Dogo Argentino breed, living in a rural area in southeastern Uruguay. An account of published cases in dogs worldwide is provided. As seen in other hosts, male dogs seem to present a predisposition for acquiring the disease

A proof-of-concept clinical trial using mesenchymal stem cells for the treatment of corneal epithelial stem cell deficiency

Producción CientíficaOcular stem cell transplantation derived from either autologous or allogeneic donor corneoscleral junction is a functional cell therapy to manage extensive and/or severe limbal stem cell deficiencies that lead to corneal epithelial failure. Mesenchymal stem cells have been properly tested in animal models of this ophthalmic pathology, but never in human eyes despite their potential advantages. We conducted a 6- to 12-month proof-of-concept, randomized, and double-masked pilot trial to test whether allogeneic bone marrow-derived mesenchymal stem cell transplantation (MSCT], n = 17) was as safe and as equally efficient as allogeneic cultivated limbal epithelial transplantation (CLET), (n = 11) to improve corneal epithelial damage due to limbal stem cell deficiency. Primary endpoints demanded combination of symptoms, signs, and the objective improvement of the epithelial phenotype in central cornea by in vivo confocal microscopy. This proof-of-concept trial showed that MSCT was as safe and efficacious as CLET. Global success at 6–12 months was 72.7%–77.8% for CLET cases and 76.5%–85.7% for MSCT cases (not significant differences). Central corneal epithelial phenotype improved in 71.4% and 66.7% of MSCT and CLET cases, respectively at 12 months (P = 1.000). There were no adverse events related to cell products. This trial suggests first evidence that MSCT facilitated improvement of a diseased corneal epithelium due to lack of its stem cells as efficiently as CLET. Consequently, not only CLET but also MSCT deserves more preclinical investigational resources before the favorable results of this proof-of-concept trial could be transformed into the larger numbers of the multicenter trials that would provide stronger evidence. (ClinicalTrials.gov number, NCT01562002.)Ministerio de Sanidad, Consumo y Bienestar Social (project SAS/2481/2009)Centro en Red de Medicina Regenerativa y Terapia Celular de Castilla y León (grant SAN 1178/200)Red de Terapia Celular TerCel (project RD12/0019/0036