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This paper presents a comprehensive study and the analysis of a topology of a no isolated DC-DC intituled Double Quadratic Boost converter with high static gain. This converter has the main advantage of high static gain and low voltage stress on its switches. The article will first present the theoretical analysis of the converter operating in an open loop. The objective of the work is the mathematical modeling and the control strategy of the converter, as well as the validation through closed-loop experimental results. Besides, we presented the practice test results to demonstrate the operation of the converter, such as the static gain experimental curve, the practice efficiency of the converter, and the control of the output voltage, as well as the capacitor voltage balance control. The authors designed a prototype for 1 kW, with a switching frequency of fs=50kHz, with FPGA-based command and modulation.

La cateterización venosa central es un procedimiento común en la actualidad, pero no está exento de complicaciones. Una de ellas, poco frecuente, pero con mortalidad elevada, es la perforación miocárdica. Se presenta el caso de una paciente que ingresa en nuestro servicio tras cirugía urgente abdominal, portadora de catéter venoso central para alimentación parenteral, y a las 48 h de ingreso presenta taponamiento pericárdico secundario a perforación cardíaca y extravasación de nutrición parenteral. Este caso clínico pone de manifiesto una compilación infrecuente pero grave, y que requiere un alto índice de sospecha para su diagnóstico y tratamiento.

Brassicaceae plants are of great interest for human consumption due to their wide variety and nutritional qualities. Of the more than 4000 species that make up this family, about a hundred varieties of 6-8 genera are extensively cultivated. One of the most interesting aspects is its high content of glucosinolates, which are plant secondary metabolites with widely demonstrated anti-oncogenic properties that make them healthy. The most relevant Brassicaceae studies related to food and melatonin are examined in this paper. The role of melatonin as a beneficial agent in seedling grown mainly in cabbage and rapeseed and in the postharvest preservation of broccoli is especially analyzed. The beneficial effect of melatonin treatments on the organoleptic properties of these commonly consumed vegetables can be of great interest in the agri-food industry. Melatonin application extends the shelf life of fresh-cut broccoli while maintaining optimal visual and nutritional parameters. In addition, an integrated model indicating the role of melatonin on the organoleptic properties, the biosynthesis of glucosinolates and the regulatory action of these health-relevant compounds with anti-oncogenic activity is presented.

Este trabajo analiza la integración de las TIC a partir del uso didáctico de las tabletas digitales con alumnado de 6º de Ed. Primaria en un centro privado concertado de la provincia de Valencia (España). Los objetivos del estudio son analizar el uso didáctico que realiza el profesorado con los iPads, analizar el tipo de tareas de aprendizaje que realiza el alumnado, averiguar a qué dimensiones de aprendizaje y desempeño personal y académico afectan e identificar los factores de la escuela que favorecen el uso pedagógico de las TIC en 6º de Ed. Primaria. Para ello, se ha realizado un estudio de caso en el que han participado 103 alumnos y alumnas, y 6 docentes. Como instrumentos de recolección de datos se ha construido un cuestionario para identificar la visión del alumnado; se han realizado entrevistas semiestructuradas para conocer la percepción del profesorado; se han analizado los documentos institucionales del centro; y se ha pasado una ficha de registro de procesos de aula en las que el profesorado ha descrito tres sesiones y el uso que han hecho en ellas del iPad. Los resultados muestran que las tabletas inciden en la motivación del alumnado y, a través de sus aplicaciones, permiten el trabajo colaborativo y el aprendizaje del manejo de software, así como la posibilidad de construir aprendizajes significativos. Todo ello se ve favorecido por diversos factores facilitadores de la integración de las TIC en el centro. No obstante, la integración didáctica es compleja por la falta de formación en el uso pedagógico de las TIC del profesorado y de la carencia de un Plan TIC. Se concluye que las tabletas permiten mejorar los procesos de enseñanzaaprendizaje en el centro, aunque es necesaria una mejora en la competencia digital docente, y la clarificación y elaboración de un Plan TIC. This work analyzes the integration of ICT from the didactic use of digital tablets with 6th grade primary school students in a private subsidized school in the province of Valencia (Spain). The objectives of the study are to analyze the didactic use that teachers make with iPads, analyze the type of learning tasks that students carry out, find out what dimensions of learning and personal and academic performance they affect and identify the factors of the school that favor the pedagogical use of ICT in 6th grade of Primary Education. For this, a case study has been carried out with the participation of 103 students and 6 teachers. As data collection instruments, a questionnaire has been constructed to identify the vision of the students; semi-structured interviews have been carried out to know the perception of the teaching staff; the school institutional documents have been analyzed; and a record of classroom processes has been passed in which the teachers have described three sessions and the use they have made of the iPad in them. The results show that tablets affect student motivation and, through their applications, allow collaborative work and learning to use software, as well as the possibility of constructing meaningful learning. All of this is favored by several factors that facilitate the integration of ICT in the school. However, didactic integration is complex due to the lack of training in the pedagogical use of ICT for teachers and the lack of an ICT Plan. It is concluded that the tablets allow to improve the teaching-learning processes in the school, although an improvement in the teaching digital competence and the clarification and elaboration of an ICT Plan is necessary.

Objective: Sensory deficits are important risk factors for delirium but have been investigated in single-center studies and single clinical settings. This multicenter study aims to evaluate the association between hearing and visual impairment or bi-sensory impairment (visual and hearing impairment) and delirium. Design: Cross-sectional study nested in the 2017 "Delirium Day" project. Setting and participants: Patients 65 years and older admitted to acute hospital medical wards, emergency departments, rehabilitation wards, nursing homes, and hospices in Italy. Methods: Delirium was assessed with the 4AT (a short tool for delirium assessment) and sensory deficits with a clinical evaluation. We assessed the association between delirium, hearing and visual impairment in multivariable logistic regression models, adjusting for: Model 1, we included predisposing factors for delirium (ie, dementia, weight loss and autonomy in the activities of daily living); Model 2, we added to Model 1 variables, which could be considered precipitating factors for delirium (ie, psychoactive drugs and urinary catheters). Results: A total of 3038 patients were included; delirium prevalence was 25%. Patients with delirium had a higher prevalence of hearing impairment (30.5% vs 18%; P < .001), visual impairment (24.2% vs 15.7%; P < .01) and bi-sensory impairment (16.2% vs 7.5%) compared with those without delirium. In the multivariable logistic regression analysis, the presence of bi-sensory impairment was associated with delirium in Model 1 [odds ratio (OR) 1.5, confidence interval (CI) 1.2-2.1; P = .00] and in Model 2 (OR 1.4; CI 1.1-1.9; P = .02), whereas the presence of visual and hearing impairment alone was not associated with delirium either in Model 1 (OR 0.8; CI 0.6-1.2, P = .36; OR 1.1; CI 0.8-1.4; P = .42) or in Model 2 (OR 0.8, CI 0.6-1.2, P = .27; OR 1.1, CI 0.8-1.4, P = .63). Conclusions and implications: Our findings support the importance of routine screening and specific interventions by a multidisciplinary team to implement optimal management of sensory impairments and hence prevention and the management of the patients with delirium.

Background/aim Paraneoplastic syndrome symptoms include isolated involuntary weight loss (IIWL). The differential diagnosis of cancer from other diseases may require a significant number of tests. Tumour markers (TMs) can be used for the diagnosis and stratification of patients according to cancer risk. Patients and methods This study included 606 patients (48% females) seen at the rapid diagnostic unit for IIWL. We determined the levels of TMs carcinoembryonic antigen, carbohydrate antigen 19-9, soluble fragments of cytokeratin 19, carbohydrate antigen 15-3, carbohydrate antigen 125, neuron specific enolase, alpha-fetoprotein, prostatic specific antigen using the multiparametric analyser COBAS 601. Two cut-off points were established, the upper reference limit described by the manufacturer and a high cut-off point suggested by Molina et al., to stratify patients according to cancer risk. Results Patients were classified according to TM levels as follows: I) all TMs below the upper reference limit; II) highest number of TMs between the two cut-offs; III) at least one TM above the higher cut-off. The odds ratio for malignancy was 4.3 for group II and 248 for group III. These results indicate that when at least one TM is above the higher cut-off, neoplasia is highly probable. Conclusion TM determination allowed to establish cancer risk in patients with IIWL.

Los espacios forestales son una fuente de servicios, tanto ambientales como económicos, de gran importancia para la sociedad. La caracterización de estos ambientes ha requerido tradicionalmente de un laborioso trabajo de campo. La aplicación de técnicas de teledetección ha proporcionado una visión más amplia a escala espacial y temporal, a la par que ha generado una reducción de los costes. La utilización de sensores óptico-pasivo multiespectrales y de sensores radar posibilita la estimación de parámetros forestales, si bien el desarrollo de sensores LiDAR, como el caso de los escáneres láser aeroportados (ALS), ha mejorado la caracterización tridimensional de la estructura de los bosques. La disponibilidad pública de dos coberturas LiDAR, generadas en el marco del Plan Nacional de Ortofotografía Aérea (PNOA), ha abierto nuevas líneas de investigación que permiten proporcionar información útil para la gestión forestal. La presente tesis utiliza datos LiDAR aeroportados de baja densidad para estimar diversas variables forestales, con ayuda de trabajo de campo, en masas forestales de Pino carrasco (Pinus halepensis Miller) en Aragón. La investigación aborda dos cuestiones relevantes como son la exploración de las metodologías más adecuadas para estimar variables forestales considerando escalas locales y regionales, teniendo en cuenta las posibles fuentes de error en el modelado; y, además, analiza la potencialidad de los datos LiDAR del PNOA para el desarrollo de aplicaciones forestales que valoricen las áreas forestales como recursos socio-económicos. La tesis se ha desarrollado según la modalidad de compendio de publicaciones, incluyendo cuatro trabajos que dan respuesta a los objetivos planteados. En primer lugar, se realiza un análisis comparativo de distintos modelos de regresión, paramétricos y no paramétricos, para estimar la pérdida de biomasa y las emisiones de CO2 en un incendio, mediante la utilización de datos LiDAR-PNOA y datos ópticos del satélite Landsat 8. En segundo lugar, se explora la idoneidad de distintos métodos de selección de variables para estimar biomasa total en masas de Pino carrasco utilizando datos LiDAR de baja densidad. En tercer lugar, se cuantificó y cartografió la biomasa residual forestal en el conjunto de masas de Pino carrasco de Aragón y se evaluó el efecto de diversas características de la tecnología LiDAR y de las variables ambientales en la precisión de los modelos. Finalmente, se analiza la transferibilidad temporal de modelos para estimar a escala regional siete variables forestales, utilizando datos LiDAR-PNOA multi-temporales. A este respecto, se compararon dos enfoques que permiten analizar la transferibilidad temporal: en primer lugar, el método directo ajusta un modelo para un determinado punto en el tiempo y estima las variables forestales para otra fecha; por otra parte, el método indirecto ajusta dos modelos diferentes para cada momento en el tiempo, estimando las variables forestales en dos fechas distintas. Los resultados obtenidos y las conclusiones derivadas de la investigación indican que la técnica basada en coeficientes de correlación de Spearman y el método de selección por todos los subconjuntos constituyen los métodos de selección de métricas LiDAR más apropiados para la modelización. El análisis de métodos de regresión para la estimación de variables forestales indicó que su idoneidad variaba de acuerdo con el tamaño y complejidad de la muestra. El método de regresión linear multivariante arrojó mejores resultados que los métodos no-paramétricos en el caso de muestras pequeñas. Por el contrario, el método Support Vector Machine produjo los mejores resultados con muestras grandes. El incremento de la densidad de puntos y de los valores de penetración de los pulsos LiDAR en el dosel, así como la presencia de ángulos de escaneo pequeños, incrementó la exactitud de los modelos. De forma similar, el incremento de la pendiente y la presencia de arbustos en el sotobosque implican una reducción en la exactitud de los modelos. En la estimación de variables forestales utilizando datos LiDAR multi-temporales, aunque la utilización del enfoque indirecto arrojó generalmente una mayor precisión en los modelos, se obtuvieron resultados similares con el enfoque directo, el cual constituye una alternativa óptima para reducir el tiempo de modelado y los costes de realización de trabajo de campo. La fusión de datos LiDAR y datos óptico-pasivos ha evidenciado la conveniencia de los métodos aplicados para cuantificar las emisiones de CO2 a la atmósfera generadas por un incendio. Esta metodología constituye una alternativa adecuada cuando no existen datos multi-temporales LiDAR. La estimación de variables de inventario forestal, así como de diversas fracciones de biomasa, como la biomasa total y la biomasa residual forestal, proporciona información valiosa para caracterizar las masas forestales mediterráneas de Pino carrasco y mejorar la gestión forestal Forest ecosystems provide environmental and economic services of great importance to the society. The characterization of these environments has been traditionally accomplished with intense field work. In comparison, the application of remote sensing tools provides a greater overview over large spatial and temporal scales while minimizing costs. Although optical data and Synthetic Aperture Radar (SAR) allow estimating forest stand variables, the development of LiDAR sensors such as Airborne Laser Scanner (ALS) have improved three-dimensional characterization of forest structure. The availability of two ALS public data coverages for the Spanish territory, provided by the National Plan for Aerial Ortophotography (PNOA), opens new research opportunities to generate useful information for forest management. This PhD Thesis used low-density ALS-PNOA data to estimate different forest variables, with support in fieldwork, in the Aleppo pine (Pinus halepensis Miller) forests of Aragón region. The addressed research is relevant mainly for two reasons: first, the examination of suitable methodologies and error sources in forest stand variables prediction at local (small area) and regional scales (large area), and second, the application of ALS data to the characterization of forest areas as a socio-economic reservoir. This PhD Thesis is a compendium of four scientific papers, which sequentially answer the objectives established. Firstly, a comparative analysis of different parametric and non-parametric models was performed to estimate biomass losses and CO2 emissions using low-density ALS and Landsat 8 data in a burnt Aleppo pine forest. Secondly, we assess the suitability of variable selection methods when estimating total biomass in Aleppo pine forest stands using low-density ALS data. In the third manuscript, the quantification and mapping of forest residual biomass in Aleppo pine forest of Aragón region and the assessment of the effect of ALS and environmental variables in model accuracy were accomplished. Finally, the temporal transferability of seven forest stands attributes modelling using multi-temporal ALS-PNOA data in Aleppo pine forest at regional scale was explored. In this case, the temporal transferability was assessed comparing two methodologies; the direct and indirect approach. The first one fits a model for one point in time and estimates the forest variable for another point in time. The indirect approach adjusts two models in different points in time to estimate the forest variables in two different dates. The results derived from this research indicated that Spearman’s rank and All Subset Selection are the most appropriate methods in the ALS metrics selection step commonly applied in modelling. The suitability of the regression methods depends on the sample size and complexity. Thus, multivariate linear regression outperformed non-parametric methods with small samples while support vector machine was the most accurate method with larger samples. Model accuracy increased with higher point density and canopy pulse penetration, while decreasing with wider scan angles. Furthermore, the presence of steep slopes and shrub reduced model performance. In the case of forest stand variables prediction using multi-temporal ALS data, although the indirect approach produced generally a higher precision, the direct approach provided similar results, constituting a suitable alternative to reduce modelling time and fieldwork costs. The fusion of ALS and passive optical data have evidenced the suitability of this information for quantifying wildfire CO2 emissions to atmosphere, constituting a good alternative when multi-temporal ALS data is not available. The estimation of forest inventory variables as well as different biomass fractions, such as total biomass and forest residual biomass, provided valuable information to characterize Mediterranean Aleppo pine forests and improve forest management.

Objective. To evaluate the role played by anakinra in the treatment of patients with severe COVID-19 who fail to “accepted” standard of care and tocilizumab.Methods. We conducted a retrospective cohort study assessed in Althaia Health Network University and Vall d’Hebrón University Hospital, in Barcelona, Spain. We included patients with confirmed RT-PCR for SARS-CoV-2, moderate-to-severe acute respiratory distress syndrome [PaO2:FiO2] (PAFI) ≤200 mmHg, and hyperinflammation. All of them were primarily managed with non-invasive ventilation outside of the ICU and received standard of care with hydroxychloroquine, lopinavir/ritonavir, azithromycin, and enoxaparin supplemented with tocilizumab. These patients received an additional administration of 100 mg subcutaneous anakinra twice a day (low-dose) or every 6-8 hours (medium-dose). Mechanical ventilation-free survival, ICU admission, respiratory function changes (PAFI), inflammatory markers, and survival were analyzed.Results. Clinical and respiratory improvements were already present at 48 hours post-anakinra. PAFI increased 105.2% at 48 hours over anakinra administration and 166.9% at day 7. Respiratory function improvement was significant at day 7 (pConclusions. In severe ARDS related to SARS-CoV-2 refractory to standard of care plus tocilizumab, low-to-moderate doses of anakinra as a rescue therapy showed effectiveness and safety, avoiding mechanical ventilation and deaths.

When multiple loads need to be supplied with variable voltage and/or frequency, one of the interests is to reduce the number of power devices of the topology used, in order to reduce the cost and volume of the converter. This paper proposes a topology that combines features of standard two- and three-level converters with reduced number of switches. The converter is capable to produce a quasi-three-level output voltage and is suitable to supply multiple loads. In this work, the topology is proposed to be used in a multiple-machine solar pumping system. The converter is operated to extract the maximum available power from a photovoltaic array and a predictive control strategy is proposed to regulate the machine currents as well as to balance the voltages of the converter input capacitors. Simulations of the system considering two pump drives are presented and discussed.

Introduction: Centenarians and nonagenarians constitute a rapidly growing age group in Western countries and they are expected to be admitted to hospital with hip fractures. The aim of this study was to compare outcomes of centenarian and nonagenarian patients following a hip fracture and to identify risk factors related to in-hospital and post-discharge mortality in both groups. Patients and methods: A prospective evaluation of centenarian patients and nonagenarian controls admitted to a tertiary university hospital in Barcelona with hip fractures over a period of 5 years and 9 months. Baseline characteristics and outcomes in both patient groups were compared. Variables associated with in-hospital, 30-day, 3-month and 1-year mortality were also analyzed. Results: Thirty-three centenarians and 82 nonagenarians were included. The most relevant statistically significant differences found were: Barthel index at admission (61.90 vs. 75.22), number of drugs before admission (4.21 vs 5.55), in-hospital complication rates (97 vs. 78%), readmissions at 3 months and 1 year (0 vs 11.7% and 3.4 vs. 19.5% respectively) and mortality at 3 months and 1 year (41.4 vs. 20.8% and 62.1 vs. 29.9%, respectively). Mean number of complications, rapid atrial fibrillation, mean age, and urinary tract infection were risk factors associated with mortality. Conclusions: Centenarian patients had similar in-hospital outcomes to nonagenarians, but experienced more complications and twice the 3-month and 1-year mortality rate. The mean number of complications was the risk factor most consistently related to in-hospital and post-discharge mortality. These findings emphasize the need to improve care in very old patients to prevent complications. (C) 2018 Elsevier Ltd. All rights reserved.

This work describes the electrochemical, spectroscopic and electrochemiluminescent (ECL) characterization of graphite screen-printed electrodes (SPE) modified with a multilayer electrostatic assembly between 3-aminopropyltriethoxysilane (APTES) and CdTe quantum dots stabilized with glutathione (GSH) as the cationic and the negative layers, respectively. The characterization of the obtained system was performed by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscopy and Raman spectroscopy, which confirm the homogeneous presence of CdTe quantum dots on the multilayer assembly. The electrochemiluminescent properties were measured in a potentiostat coupled with a photodiode detector, showing stable and repetitive electrochemiluminescent signals. The ECL response was studied using potassium persulfate and hydrogen peroxide as co-reactants, and the measurements were carried out at different scan rates, pH values and concentrations. The ECL properties of the studied system at specific experimental conditions demonstrated different mechanisms by changing the co-reactants associated with the electrochemical step to generate the radical species and its interaction with the SPE/APTES/CdTe (GSH) reduced system, obtaining a more intense ECL signal with H2O2 than with S2O82−. Some analytical parameters, such as the linear range and the limit of detection for SPE/APTES/CdTe (GSH) in ECL H2O2 detection, were obtained.

Conicyt-Fondecyt CHILE 1161225 CONICYT USACH scholarship Bureau of Educational and Cultural Affairs of the United States Department of State

Co−doped stannates, Zn 2-x Co x SnO 4 (0.5 ≤ x ≤ 1.5), were produced by ceramic synthesis starting from the ZnSnO 4 phase. Morphology, structure, and composition of synthesized compounds were examined using scanning electron microscopy, X-ray diffraction analysis (XRD), and X-ray photoelectron spectroscopy (XPS). Using XPS, cobalt ions are shown to have an oxidation state of 2 + , and XRD patterns showed the same crystalline structure for all Zn 2-x Co x SnO 4 (0.5 ≤ x ≤ 1.5) phases, i.e., they are isostructural. The morphology of synthesized compounds shows appreciable differences in particle sizes which range from 80 nm to 500 nm, depending on how the ceramic was synthesized and the cobalt concentration. Co−doped stannates ⁄reduced graphene (rGO) composites were prepared and used to modify glassy carbon electrodes (GCE). The resulting electrodes were evaluated for the amperometric determination of hydrogen peroxide. The catalytic activity of composites towards the oxidation of hydrogen peroxide was highly dependent on quantity of cobalt in the ceramic compound, and also on the quantity of rGO present in the composite. The pure cobalt stannate phase with a ratio of 8:1 (ceramic:rGO) exhibited the best catalytic activity towards hydrogen peroxide oxidation at low potentials (0.400 V). A linear relationship between current and hydrogen peroxide concentration was obtained with a sensitivity of 0.43 μAmM −1 cm −2 and a detection limit of 0.31 μM.

Introduction Previous studies of antihypertensive treatment of older patients have focused on blood pressure control, cardiovascular risk or adherence, whereas data on inappropriate antihypertensive prescriptions to older patients are scarce. Objectives The aim of the study was to assess inappropriate antihypertensive prescriptions to older patients. Methods An observational, prospective multicentric study was conducted to assess potentially inappropriate prescription of antihypertensive drugs, in patients aged 75 years and older with arterial hypertension (HTN), in the month prior to hospital admission, using four instruments: Beers, Screening Tool of Older Person's Prescriptions (STOPP), Screening Tool to Alert Doctors to the Right Treatment (START) and Assessing Care of Vulnerable Elders 3 (ACOVE-3). Primary care and hospital electronic records were reviewed for HTN diagnoses, antihypertensive treatment and blood pressure readings. Results Of 672 patients, 532 (median age 85 years, 56% female) had HTN. 21.6% received antihypertensive monotherapy, 4.7% received no hypertensive treatment, and the remainder received a combination of antihypertensive therapies. The most frequently prescribed antihypertensive drugs were diuretics (53.5%), angiotensin-converting enzyme inhibitors (ACEIs) (41%), calcium antagonists (32.2%), angiotensin receptor blockers (29.7%) and beta-blockers (29.7%). Potentially inappropriate prescription was observed in 51.3% of patients (27.8% overprescription and 35% underprescription). The most frequent inappropriately prescribed drugs were calcium antagonists (overprescribed), ACEIs and beta-blockers (underprescribed). ACEI and beta-blocker underprescriptions were independently associated with heart failure admissions [ beta-blockers odds ratio (OR) 0.53, 95% confidence interval (CI) 0.39-0.71, p < 0.001; ACEIs OR 0.50, 95% CI 0.36-0.70, p < 0.001]. Conclusion Potentially inappropriate prescription was detected in more than half of patients receiving antihypertensive treatment. Underprescription was more frequent than overprescription. ACEIs and beta-blockers were frequently underprescribed and were associated with heart failure admissions.

This paper presents a study of a new dc-dc non-isolated high gain converter called Double Zeta Quadratic Converter. From a single basic switching cell of a family of quadratic converters, the topological states, the waveforms of voltage and current, and the output characteristic graph of the converter are presented in this paper. To prove the advantages of this new topology as the high static gain and high efficiency, the raised curves are illustrated. Besides, the experimental results of the proposed converter are presented in this paper.

This work presents various multilevel converters obtained from basic dc-dc converters for high-voltage and high-power applications. Several cells are proposed, which have a single switching pattern realized via a simple modulator circuit that compares triangular carriers with a sine modulator. One of the main features of the proposed circuits is that some transistors work at low frequency and withstanding high voltages or high currents, while others are switched at high frequency and low voltage or low current levels. The topologies can be classified as hybrid. In addition, taking account that having the slow bridge as an output circuit means that a reduced number of semiconductor components leads to a relatively high number of levels.

© The Author(s)., For the first time, the synthesis, characterization, and analytical application for hydrogen peroxide quantification of the hybrid materials of Co2TiO4 (CTO) and reduced graphene oxide (RGO) is reported, using in situ (CTO/RGO) and ex situ (CTO+RGO) preparations. This synthesis for obtaining nanostructured CTO is based on a one-step hydrothermal synthesis, with new precursors and low temperatures. The morphology, structure, and composition of the synthesized materials were examined using scanning electron microscopy, X-ray diffraction (XRD), neutron powder diffraction (NPD), and X-ray photoelectron spectroscopy (XPS). Rietveld refinements using neutron diffraction data were conducted to determine the cation distributions in CTO. Hybrid materials were also characterized by Brunauer–Emmett–Teller adsorption isotherms, Scanning Electron microscopy, and scanning electrochemical microscopy. From an analytical point of view, we evaluated the electrochemical reduction of hydrogen peroxide on glassy carbon electrodes modified with hybrid materials. The analytical detection of hydrogen peroxide using CTO/RGO showed 11 and 5 times greater sensitivity in the detection of hydrogen peroxide compared with that of pristine CTO and RGO, respectively, and a two-fold increase compared with that of the RGO+CTO modified electrode. These results demonstrate that there is a synergistic effect between CTO and RGO that is more significant when the hybrid is synthetized through in situ methodology., Funding was provided by Conicyt-Fondecyt Chile (Grant N°1161225), Conicyt-FONDEQUIP Chile (Grant N° EQM170111), and Redes de Investigación 021842SG_RED: RCNM-USACH “Red de Caracterización de NanoMateriales—Universidad de Santiago de Chile”. Additional funding was provided by Ministerio de Economia (MINECO, Spain) under project RTI2018-095303-B-C51.

Background/aim There are two strategies for the interpretation of tumor markers (TM) in fluid effusions: i) high cut-off and ii) fluid/serum ratio (F/S) and low cut-off. The objective of this study is to compare these two strategies and to determine whether diagnostic accuracy improves by the identification of possible false positives using Adenosine deaminase (ADA), C reactive protein (CRP) and % of polymorphonuclear cells (%PN). Patients and methods We studied 157 ascitic fluids, 74 of which were malignant. ADA, CRP and %PN were determined in ascitic fluid, and Carcinoembryonic antigen (CEA), Cancer antigen 72-4 (CA72-4), Cancer antigen CA19-9 and Cancer antigen 15-3 (CA15-3) in both fluid and serum. Results The strategy of high cut-off showed 59.5% sensitivity at 100% specificity. The F/S strategy showed 75.7% sensitivity at 95.2% specificity. Subclassifying cases with ADA, CRP and %PN negative showed 67.5% sensitivity at 100% specificity for high cut-off and for the F/S strategy was 81.7% sensitivity at 98.7% specificity. Conclusion The strategy of F/S with negative ADA, CRP and %PN allow the best interpretation for TM in the ascitic fluid.

For the first time, the synthesis, characterization, and analytical application for hydrogen peroxide quantification of the hybrid materials of Co2TiO4 (CTO) and reduced graphene oxide (RGO) is reported, using in situ (CTO/RGO) and ex situ (CTO+RGO) preparations. This synthesis for obtaining nanostructured CTO is based on a one-step hydrothermal synthesis, with new precursors and low temperatures. The morphology, structure, and composition of the synthesized materials were examined using scanning electron microscopy, X-ray diffraction (XRD), neutron powder diffraction (NPD), and X-ray photoelectron spectroscopy (XPS). Rietveld refinements using neutron diffraction data were conducted to determine the cation distributions in CTO. Hybrid materials were also characterized by Brunauer–Emmett–Teller adsorption isotherms, Scanning Electron microscopy, and scanning electrochemical microscopy. From an analytical point of view, we evaluated the electrochemical reduction of hydrogen peroxide on glassy carbon electrodes modified with hybrid materials. The analytical detection of hydrogen peroxide using CTO/RGO showed 11 and 5 times greater sensitivity in the detection of hydrogen peroxide compared with that of pristine CTO and RGO, respectively, and a two-fold increase compared with that of the RGO+CTO modified electrode. These results demonstrate that there is a synergistic effect between CTO and RGO that is more significant when the hybrid is synthetized through in situ methodology.