2,071 research outputs found

    PathFinder: A Visualization eMathTeacher for Actively Learning Dijstra's algorithm

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    PathFinder is a new eMathTeacher for actively learning Dijkstra's algorithm. In Sanchez-Torrubia et al. (2007) the concept of eMathTeacher was defined and the minimum as well as some additional requirements were described. The tool presented here is an enhanced paradigm of this new concept on Computer Aided Instruction (CAI) resources: an application designed following the eMathTeacher philosophy for active eLearning. The highlighting new feature provided by this application is an animated algorithm visualization panel showing, on the code, the current step the student is executing and/or where there is a user's mistake within the algorithm running. PathFinder also includes another two interesting new features: an active framework area for the algorithm data and the capability of saving/retrieving the created graph

    Nuevos fotocatalizadores Sm2FeTaO7 y Sm2InTaO7 para la eliminación de contaminantes presentes en el agua

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    En esta investigación se reporta por primera vez la síntesis del óxido tipo pirocloro Sm2FeTaO7 por los métodos de reacción en estado sólido y sol-gel, así como el óxido Sm2InTaO7 mediante sol-gel. Los resultados de la caracterización estructural revelaron que el óxido Sm2FeTaO7 cristaliza en el sistema monoclínico con grupo espacial C2/c mientras que el óxido Sm2InTaO7 cristaliza en el sistema cúbico y grupo espacial Fd-3m. Para ambos materiales, cuando se utilizó el método sol-gel se obtienen materiales con propiedades morfológicas y superficiales diferentes, principalmente, en su tamaño de partícula y área superficial específica. La evaluación fotocatalítica mostró que el Sm2FeTaO7 es activo en la eliminación del colorante índigo carmín bajo condiciones reales de radiación solar. Mientras que, el Sm2InTaO7 es eficiente para reducir el ion Cr (VI) y degradar el colorante cristal violeta

    Chronic Obstructive Pulmonary Disease and Incidence of Hip Fracture: A Nested Case-Control Study in the EpiChron Cohort

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    Purpose: To determine whether chronic obstructive pulmonary disease (COPD) is a risk factor for hip fracture and identify other factors associated with hip fracture. Patients and Methods: Observational nested case-control study was conducted in Aragon, Spain in 2010. We included COPD patients aged >40 years, in the EpiChron cohort. Each COPD patient was matched for age, sex, and number of comorbidities with a control subject without COPD. Patients with an existing diagnosis of osteoporosis and those with hip fracture before 2011 were excluded. We collected baseline demographic, comorbidity, and pharmacological treatment data. During a 5-year follow-up period, we recorded the incidence of hip fracture. A logistic regression model was constructed to identify factors associated with hip fracture. Results: The study population consisted of 26, 517 COPD patients and the same number of controls (median [interquartile range] age, 74 [17] years; women, 24.7%). Smoking and heart failure were more frequent in COPD patients, and obesity, hypertension, diabetes, dyslipidemia, stroke, arthritis, and visual or hearing impairment were less frequent (all p<0.001). Consumption of benzodiazepines (p=0.037), bronchodilators (p<0.001), and corticosteroids (p<0.001) was higher in the COPD group, while that of beta-blockers and thiazides was lower (both p<0.001). During follow-up, 898 (1.7%) patients experienced hip fracture, with no differences observed between COPD and control patients. Multivariate analysis revealed that independent of COPD status, age, female sex, chronic liver disease, heart failure, and benzodiazepine use were independently associated with a higher risk of hip fracture, and obesity with a lower risk. In COPD patients, use of inhaled anticholinergics was independently associated with hip fracture (OR, 1.390; 95% CI 1.134-1.702; p=0.001). Conclusion: COPD is not a risk factor for a hip fracture within 5 years. The association between the use of inhaled anticholinergics and risk of hip fracture warrants further study

    Electrocatalytic behavior of tetrathiafulvalene (TTF) and extended tetrathiafulvalene (exTTF) [FeFe] hydrogenase mimics

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    TTF- and exTTF-containing [(μ-S2)Fe2(CO)6] complexes have been prepared by the photochemical reaction of TTF or exTTF and [(μ-S2)Fe2(CO)6]. These complexes are able to interact with PAHs. In the absence of air and in acid media an electrocatalytic dihydrogen evolution reaction (HER) occurs, similarly to analogous [(μ-S2)Fe2(CO)6] complexes. However, in the presence of air, the TTF and exTTF organic moieties strongly influence the electrochemistry of these systems. The reported data may be valuable in the design of [FeFe] hydrogenase mimics able to combine the HER properties of the [FeFe] cores with the unique TTF propertie

    Phosphite Bearing [(μ-ADT)RFe2(CO)6] (ADT = Azadithiolate) Moieties: A Tool for the Building of Multimetallic [FeFe]-Hydrogenase Mimics

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    A new phosphite ligand having three [(μ-ADT)RFe2(CO)6] (R= p-HOC6H4) moieties (2) has been prepared in good yield by the reaction of complex [(μ-ADT)RFe2(CO)6] (R= p-HOC6H4) 1a with PCl3. Coordination of this phosphite to [PdCl2(MeCN)2] or [PtCl2(DMSO)2] forms heterometallic square planar complexes 5 (C84H48Cl2Fe12N6O42P2MS12) (M = Pt, Pd) in excellent yields. Three-legged piano stool complexes 6 (C52H39Cl2Fe6N3O21PMS6) (M = Rh, Ir) were obtained by the reaction of phosphite 2 with [MCl2Cp*]2(M = Rh, Ir) in good yields. The formation of complexes 5 and 6 demonstrates the versatility of this new ligand for forming different heteropolymetallic complexes under mild reaction conditions. Moreover, the open-chain derivatives [(μ-ADT)RFe2(CO)6] (R= HOCH2CH2, o-HOC6H4) (1b and 1c, respectively) form cyclic complexes 4 by spontaneous intramolecular CO substitution by the P atom in one of the three [FeFe] fragments. The electrocatalytic behavior of complexes 2 and 4 upon the addition of AcOH is similar to that of related [(μ-ADT)Fe2(CO)6] derivatives. The successive additions of AcOH cause an increase in the current intensity in the wave at about -1.80 V for heteropolymetallic complexes 5 and 6. However, the appearance of a new wave around -1.40 V in complexes 5 points to an acid-promoted side reaction in the electrochemical proces

    Impact of the implementation of the AAN epilepsy quality measures on the medical records in a university hospital

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    Background: The American Academy of Neurology (AAN) suggested eight quality measures to be observed at every patient visit. The aim of this work is to compare the percentage of documentation of each measure before and after the implementation of a new worksheet in a third-level center. Methods: Quasi-experimental study including medical records filled by medical school seniors and junior residents supervised by an epileptologist. The authors surveyed 80 consecutive charts of people with epilepsy who were seen in the outpatient clinic before and after the intervention. McNemar change test was used to compare the percentages of documentation of each quality measure–i.e., seizure type and frequency, etiology, EEG, MRI/CT head scans, AED side effects, surgical therapy referral, safety counseling, preconception counseling–and physical exam. Each quality measure was considered to be fulfilled only if it was assessed and properly recorded. Results: Mean age was 35(±13) years, 55% women, mean epilepsy onset at age 18(±15), 82% presented with partial-onset seizures. The reporting rate improved for all quality measures (previous vs new), reaching statistical significance for: seizure type 80vs94% (p < 0.05), AED side effects 8vs24%, etiology 66vs88% (p < 0.01), safety counseling 5vs64%, preconception counseling 4vs20%, and physical exam 63vs94% (p < 0.001). Conclusion: A quality-oriented epilepsy worksheet led to a better practice standardization and documentation of AAN standards for diagnostic and counseling purposes. Further evaluations should be undertaken to assess the impact on medical education and patient care

    Tratamiento Laparoscópico de la úlcera péptica duodenal. Resultados a mediano y largo plazos.

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    Aunque en la actualidad la cirugía electiva de la úlcera péptica duodenal se realiza con menos frecuencia, las indicaciones para el tratamiento quirúrgico continúan siendo las mismas y existe un pequeño número de pacientes que aún debe ser operado. Las modalidades de vagotomías laparoscópicas más aceptadas han sido las de Taylor (vagotomía troncular posterior y seromiotomía gástrica anterior) y de Hill-Barker (vagotomía troncular posterior y vagotomía altamente selectiva anterior), debido a su eficacia, seguridad y simplicidad. El objetivo de este estudio es evaluar los resultados a mediano y largo plazos de estas técnicas laparoscópicas. Entre 1994 y 2001, fueron realizadas en el Centro Nacional de Cirugía de Mínimo Acceso 183 vagotomías laparoscópicas (108 vagotomías de Hill-Barker y 75 vagotomías de Taylor). Los pacientes fueron seguidos prospectivamente para evaluar mediante variables como: tiempo quirúrgico, mortalidad, morbilidad, efectos colaterales de la operación y recurrencia de la enfermedad; la practicabilidad de los procedimientos, su seguridad y los resultados funcionales a largo plazo. El tiempo quirúrgico promedio fue 116,3 minutos para la técnica de Hill-Barker, y 149.2 minutos para la técnica de Taylor. No hubo conversión a cirugía convencional y la mortalidad perioperatoria fue nula. La estancia hospitalaria promedio fue 2.1 días. Las principales complicaciones postoperatorias fueron: diarrea (10,9%) y retardo del vaciamiento gástrico (4,4%). El índice global de recidiva fue de 10.4 %. Las vagotomías laparoscópicas constituyen la opción de tratamiento ideal para la úlcera péptica duodenal, cuando el tratamiento quirúrgico está indicado, debido a bajos índices de mortalidad, recurrencia y trastornos funcionales colaterales a largo plazo, a lo cual se añaden las ventajas de la cirugía mínimamente invasiva.  Palabras clave: Vagotomía laparoscópica, úlcera duodenal, Técnica de Hill-Barker, Técnica de Taylor

    IAA : Información y actualidad astronómica (15)

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    Sumario : INVESTIGACIÓN. Aerosoles atmosféricos: sus efectos en el clima de las atmósferas del sistema solar.-- El gas molecular en las galaxias.-- VENTANA ABIERTA. Todo un privilegio.-- CHARLAS CON...Vicent Martínez.-- ACTUALIDAD CIENTÍFICA. Un sistema planetario joven en torno a Beta Pictores.-- Una nueva visita a Canis Major .-- ACTIVIDADES IAA.-- AGENDA.Esta revista se publica con la ayuda de la Accion Especial DIF 2001-4284-E del Programa Nacional de Difusión de la Ciencia y la Tecnología, del Ministerio de Ciencia y Tecnología.N

    Candelilla wax edible coating with Flourensia cernua bioactives to prolong the quality of tomato fruits

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    The improvement of the postharvest quality of tomato fruits was evaluated using an edible coating functionalized with an Flourensia cernua extract evaluating the antifungal, structural, barrier, and optical properties. The formulation and evaluation of an edible coating and its application on tomato was evaluated using a response surface methodology to determine the ideal concentrations of candelilla wax, whey protein, and glycerol. Edible films showed good barrier properties, with water vapor permeability varying from 0.4350.404 g mm/m2 day kPa. The addition o F. cernua extract showed significant improvement in the transparency of films. The edible coating applied to tomato reduced weight and firmness loss. The sensory evaluation proved that the product obtained is acceptable for consumers. The edible coating added with F. cernua extract was the most effective in inhibiting the growth of pathogenic fungi and the visual appearance at the end of storage confirmed the beneficial effect of the edible coating.(undefined)info:eu-repo/semantics/publishedVersio
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