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The combination of hydrophobic membranes and microbial electrolysis cells (MEC) was assessed in two different configurations in order to recover ammonia from anaerobically digested pig slurry. Polytetrafluorethylene (PTFE) hydrophobic membranes were inserted both in an H-type three-chamber cell (MEC-H) and a two-chamber sandwich configuration MEC (MEC-S), both fitted with a cationic exchange membrane (CEM) dividing the anode and cathode compartments. The use of electrochemical techniques such as electrochemical impedance spectroscopy was applied to monitor the increase of the biofilm on the anode, related to the decrease of the charge transfer resistance. When operated in the higher organic loading rate (28 ± 5 kg COD m−3 d−1) the current density produced in the MEC-H was 1.40 ± 0.71 A m−2, compared to 0.61 ± 0.28 A m−2 in the MEC-S. The flux of ammonium through the CEM in the MEC-H was of 3.4 ± 1.2 g N m−2 h−1. Regarding the recovery of ammonia through the hydrophobic membrane, the flux of ammonia was of 1.5 and 0.7 g N m−2 h−1 in the MEC-H and MEC-S, respectively, mainly governed by the pH value and the ammonia concentration of the catholyte. The combination of MEC with hydrophobic membranes reveals as a suitable technology for the recovery of ammonia and treatment of high strength wastewater such as livestock. info:eu-repo/semantics/acceptedVersion

RESUMEN Introducción: Los debates en torno a los sistemas de partido en América Latina clasifican al caso colombiano como desinstitucionalizado. Aun cuando esta afirmación es indiscutiblemente acertada, suele pasar desapercibido el hecho de que existen issues que producen un efecto decantador del voto. Esto motiva, a su vez, un ordenamiento del electorado y comportamientos temporalmente consistentes, especialmente en las elecciones presidenciales. En lo que va de este siglo, el efecto se asocia al tipo de salida (militar/negociada) ofrecida para acabar con el conflicto armado interno. Desde este punto de vista, el presente trabajo pretende rastrear la manera en la que se configuran espacio-temporalmente los electorados, a favor y en contra del acuerdo de paz, en las regiones más afectadas por dicho conflicto; particularmente, en medio de la coyuntura transicional en la que se pasó de la Mesa de Conversaciones entre el gobierno y las Fuerzas Armadas Revolucionarias de Colombia a las fases de refrendación e implementación del acuerdo derivado de la misma. Materiales y Métodos: Para lograrlo, se evalúa la transferencia de votos durante las segundas vueltas presidenciales de 2014 y 2018 y en el plebiscito de paz de 2016, en los 167 municipios priorizados por las (fallidas) Circunscripciones Transitorias Especiales de Paz. Partiendo de la consideración de la volatilidad e incertidumbre típicas de los contextos de war-to-peace transition, se hace uso del modelo de inferencia ecológica a nivel de mesa de votación (se analizaron los resultados en más de 7.500 mesas), dentro de las circunscripciones señaladas. Resultados: Dentro de este marco, se identifica efectivamente a la dicotomía salida negociada/salida militar del conflicto como el eje de decantación de preferencias que produjo electorados arraigados. Sin embargo, la evidencia empírica recolectada también sugiere que las elecciones de 2018 mostraron un aumento de su fluidez. Desde este punto de vista, se aprecia que la salida del conflicto armado efectivamente configura segmentos de electores consistentes, constituyéndose como un cuasi-clivaje. Sin embargo, aunque predominen los electorados de tipo arraigado, existe un relativo nivel de fluidez que se intensificó durante las elecciones presidenciales de 2018, ofreciendo señales de un proceso de realineamiento electoral. Discusión: Este resultado muestra que, a pesar de la desinstitucionalización del sistema de partidos colombiano, existen issues articuladores del voto que producen electorados relativamente estables. Sin embargo, la existencia de un escenario de transición política y de normalización de la agenda podría estar produciendo su reconfiguración. ABSTRACT Introduction: Debates about party systems in Latin America classify the Colombian case as deinstitutionalized. Even when this statement is undoubtable, the fact that there are issues that arrange the electorate goes usually unnoticed. Hence, this motivates temporarily consistent behaviours, especially in presidential elections. So far this century, the effect is associated with the kind of exit (military / negotiated) offered to end the internal armed conflict. From this point of view, this paper intends to trace the way in which the electorate is space-temporarily configured in favour and against the peace agreement in the regions where this conflict was stronger. Particularly, in the middle of a transitional process in which the dialogue tables between the government and the FARC-EP went to the endorsement and the implementation phases. Materials and methods: To achieve this, we evaluate the transfer of votes during the second presidential rounds of 2014 and 2018, and in the 2016 peace referendum. We analyse the results in the 167 municipalities prioritized by the (failed) Special Transitory Districts of Peace. Based on the consideration of uncertainty, typical of war-to-peace transition contexts, we use an ecological inference model at the polling station level (the results were analysed in more than 7500 voting tables) distributed in the sixteen special districts. Results: Within this framework, the negotiated exit/military exit dichotomy of the conflict is effectively identified as the main axis of electorate aggregation. In fact, it produces entrenched electorates. However, the empirical evidence also suggests that the 2018 elections showed an increasing fluency. From this point of view, the exit from the armed conflict effectively configures segments of consistent voters, producing a quasi-cleavage. However, although entrenched electorates predominate, there is a relative level of fluidity (growing since the 2018 elections) offering signs of an electoral realignment process. Discussion: This result shows that, despite the deinstitutionalization of the Colombian party system, there are issues that articulate the vote and produce relatively stable electorates. However, the existence of a political transition, and a process of agenda normalization, could be generating its reconfiguration.

Graphical Abstract This online structured survey has demonstrated the global impact of the COVID-19 pandemic on vascular services. The majority of centres have documented marked reductions in operating and services provided to vascular patients. In the months during recovery from the resource restrictions imposed during the pandemic peaks, there will be a significant vascular disease burden awaiting surgeons. Graphical Abstract One of the most affected specialties

Resumen Este artículo analiza la labor periodística del joven Pedro León Arboleda en el diario Relator, de Cali, entre los años 1958 y 1959. A partir de ella se pretende contribuir en la reconstrucción biográfica de quien posteriormente resultaría ser uno de los intelectuales determinantes del debate de las izquierdas colombianas de mitad de la década de 1960; aportando elementos sobre su producción intelectual temprana y sobre su activismo en el sindicalismo de los trabajadores de la prensa. Abstract This article analyzes the early journalistic work of Pedro León Arboleda in Relator, daily newspaper of Cali, Colombia, between 1958 and 1959. So then on we pretend contribute to the biographical reconstruction of one of the determinant intellectuals of the Colombian left debate of the middle decade of 1960; providing elements of his early intellectual production and about his activism in the press workers tradeunionism.

INTRODUCTION: Despite the strong evidence of the clinical utility of QTc prolongation as a surrogate marker of cardiac risk, QTc measurement is not part of clinical routine either in hospital or in physician offices. We evaluated a novel device (“the QT scale”) to measure heart rate (HR) and QTc interval. METHOD: The QT scale is a weight scale embedding an ECG acquisition system with four limb sensors (feet and hands: lead I, II, and III). We evaluated the reliability of QT scale in healthy subjects (cohort 1) and cardiac patients (cohorts 2 and 3) considering a learning (cohort 2) and two validation cohorts. The QT scale and the standard 12‐lead recorder were compared using intraclass correlation coefficient (ICC) in cohorts 2 and 3. Absolute value of heart rate and QTc intervals between manual and automatic measurements using ECGs from the QT scale and a clinical device were compared in cohort 1. RESULTS: We enrolled 16 subjects in cohort 1 (8 w, 8 m; 32 ± 8 vs 34 ± 10 years, P = 0.7), 51 patients in cohort 2 (13 w, 38 m; 61 ± 16 vs 58 ± 18 years, P = 0.6), and 13 AF patients in cohort 3 (4 w, 9 m; 63 ± 10 vs 64 ± 10 years, P = 0.9). Similar automatic heart rate and QTc were delivered by the scale and the clinical device in cohort 1: paired difference in RR and QTc were −7 ± 34 milliseconds (P = 0.37) and 3.4 ± 28.6 milliseconds (P = 0.64), respectively. The measurement of stability was slightly lower in ECG from the QT scale than from the clinical device (ICC: 91% vs 80%) in cohort 3. CONCLUSION: The “QT scale device” delivers valid heart rate and QTc interval measurements.

Objetivo Comparar la funcion pulmonar unilateral (FPU) estimada mediante tomografia por impedancia electrica (TIE) con la misma determinacion obtenida a partir de la gammagrafia de ventilacion y perfusion pulmonar Pacientes y metodos Se trata de un estudio clinico prospectivo, realizado en un laboratorio de funcion pulmonar de un hospital general. Se incluyo a 20 pacientes diagnosticados de cancer de pulmon (17 varones y 3 mujeres, con edades comprendidas entre los 25 y los 77 anos), candidatos a cirugia resectiva pulmonar, a quienes se realizo un estudio de ventilacion/perfusion pulmonar con radioisotopos. La FPU se calculo a partir de imagenes en 2 espacios intercostales en las que se representaban la ventilacion y la perfusion relacionadas con los cambios en la bioimpedancia electrica. Se determino asimismo la participacion de cada pulmon en la funcion global a partir de estudios isotopicos. Resultados El valor promedio ± desviacion estandar de ventilacion en el pulmon derecho obtenido mediante TIE fue del 54 ± 9% (rango: 32-71%). El mismo valor mediante radioisotopos fue del 52 ± 10% (rango: 31-80%) para la ventilacion y del 50 ± 9% (rango: 37-71%) para la perfusion (prueba de la t de Student, p no significativa). El coeficiente de correlacion entre ambas determinaciones fue de r = 0,90 (p Conclusiones La TIE es capaz de cuantificar la FPU con una precision similar a la gammagrafia de ventilacion o perfusion con radioisotopos.

Atrial fibrillation (AF) is a cardiac arrhythmia characterized by a highly irregular heart rate. It is the most prevalent arrhythmia in the general population in the United States and most developed countries, and is strongly associated with increased morbidity and mortality from adverse cardiovascular and cerebrovascular events. Moreover, patients with AF are correlated with increased healthcare expenditures, making the burden of AF on society extremely large. In this proof-of-concept study, we present an innovative device to be used as a screening tool for AF. The device consists of a modified electronic scale that is able to obtain an ECG and analyse it for the presence of AF. The classification algorithm is based on the RdR map method that plots RR intervals versus change in RR intervals. After optimizing the algorithm on a learning set of 77 ECGs from 45 patients, the performance of the device during a blind validation of 76 ECGs from 44 patients was: accuracy = 83%, sensitivity = 83%, specificity = 83% (N = 76 ECGs). Applying a constraint that each ECG recording contains a minimum of 7 beats in order to be eligible for classification, accuracy improved to 89% (sensitivity = 83%, specificity = 90%, N = 70). In conclusion, we present an innovative device to detect AF in a manner that can be implemented into current physician workflow without increasing the time or cost of each clinical encounter.

AC-coupled amplifiers are noisier than dc-coupled amplifiers because of the thermal noise of the resistor(s) in the ac-coupling network and the increased contribution of the amplifier input noise current $i_{n}$ . Both contributions, however, diminish if the corner frequency $f_{c}$ of the high-pass filter observed by the signal is lowered, the cost being a longer transient response. At the same time, the presence of large resistors in the ac-coupling network suggests that the use of FET-input amplifiers will be advantageous because $i_{n}$ is smaller than in bipolar amplifiers. However, the noise floor, defined as that for a dc-coupled amplifier, can be larger for FET-input amplifiers because of their higher input voltage noise. Therefore, there is no clear criterion to decide which amplifier type is quieter. In this paper, we propose the quotient between the high-pass frequency of the signal bandwidth $(f_{L})$ and $f_{c}~(K=f_{L}/f_{c})$ as quantitative design parameter to reduce the additional noise contributed by a first-order ac-coupling network as compared with dc coupling. Using this parameter noise is greatly reduced without unnecessarily lengthening the transient response that results from the use of common qualitative design criteria. We demonstrate that relatively large $K$ values yield total noise closer to the noise floor, hence it is better not to determine $f_{L}$ at the front amplifier stage but later on in the signal chain. Furthermore, a large $K$ value permits bipolar op-amps to achieve lower noise than FET amplifiers even for capacitive signal sources, provided amplifier biasing is guaranteed.

The Driven-Right-Leg (DRL) circuit has been used for about 50 years to reduce interference due to common-mode voltage in biopotential amplifiers in scenarios that range from fixed equipment supplied from power lines to battery-supplied ambulatory monitors, and for systems that use gelled, dry, textile, and capacitive electrodes. However, power-line interference models predict that for isolation amplifiers, currently mandated by safety standards, power-line interference can often couple mostly in differential mode rather than in common mode. In this work we analyze the effect of the DRL circuit in different ECG leads to elucidate its actual effect on power-line interference reduction. It turns out that that the DRL circuit, which effectively reduces common-mode interference, affects differential-mode interference in an unpredictable way and can increase interference.

This study analyzes the implementation of a quality management system, in order to identify the key ele- ments that can be used to verify if this behaves as a model of change management and to examine its rela- tionship with the preservation of knowledge.The methodology is based on a review of documents for three different stages: before, during and after the implementation of the quality management system. It also includes a literature review, the application of polls and in-depth interviews.The investigation identified commonalities between the quality management system and change manage- ment models, elements that improve the management of public sector entities to generate ordered and stable organizational changes. El presente estudio analiza el proceso de implementación de un sistema de gestión de la calidad, con el fin de identificar los elementos claves que permitan verificar si este se comporta como un modelo de gestión del cambio organizacional y para examinar su articulación con la preservación del conocimiento.La metodología empleada se fundamentó en la revisión de documentos durante tres momentos diferentes. antes, durante y después de la implementación del Sistema de Gestión de la Calidad; también incluyó una revisión bibliográfica, la aplicación de una encuesta y la realización de entrevistas a profundidad.La investigación permitió identificar elementos comunes entre los sistemas de gestión de la calidad y los modelos de gestión del cambio organizacional, elementos que pueden mejorar la gestión de las entidades del sector público al facilitar cambios organizacionales ordenados y estables.

An unobtrusive method for short-term heart rate (HR) measurement is proposed based on impedance plethysmography (IPG). The system uses four dry electrodes that protrude from a flat surface and can obtain HR on a single hand resting on them. A finite element model of the hand helps in assessing the contribution of different arteries to the total impedance as measured from three different electrode configurations which offer a good trade-off between ease of use and signal quality. The technique has been validated by simultaneously recording the photoplethysmogram in the same hand.

OBJECTIVE: To compare differential lung function estimated by 2 methods: electrical impedance tomography (EIT) and ventilation-perfusion lung scintigraphy. PATIENTS AND METHODS: This prospective clinical study was carried out in the pulmonary function laboratory of a general hospital. Twenty patients diagnosed with lung cancer (17 men and 3 women, ranging in age from 25 to 77 years) who were candidates for lung resection underwent ventilation-perfusion lung scanning breathing radioactive gas. Differential lung function was estimated based on images taken at 2 intercostal spaces in which ventilation and perfusion were represented by changes in bioelectrical impedance. Each lung’s contribution to overall respiratory function was also calculated based on scintigraphy. RESULTS: The right lung contributed a mean (SD) of 54% (9%) of ventilation (range, 32%-71%) according to EIT. Scintigraphy similarly estimated the right lung’s contribution to be 52% (10%) of total ventilation (range, 31%-80%) and 50% (9%) of perfusion (range, 37%-71%). The difference between the 2 estimates was not significant (t test), and the correlation coefficients between them were r = 0.90 for ventilation and r=0.72 for perfusion (P

Dissertação apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Literatura. Esta tese pretende, através da análise de três temáticas fundamentais recorrentes neste autor e presentes neste livro, contribuir para a problematização duma obra de capital importância na literatura do século vinte português. O “problema da habitação” surge aqui, enquadrado na dinâmica da sua escrita, através deste “triângulo ontológico” que, pelo seu movimento, faz uma busca incessante da origem desta poética. O lugar deste O problema da habitação – alguns aspectos é posto aqui em realce pois representa, no seu âmago, o lugar da essência da própria poesia. This thesis pretends to contribute, through its analysis of three fundamental and recurring thematics in this author, to the questioning of a literary work of utmost importance in twentieth century Portuguese poetry. The “habitational problem” arises here, squared in the dynamics of its writing, through this “ontological triangle” whose movement helps to find the origin of this poetics. The position of this O problema da habitação – alguns aspectos is here emphasized because it represents in its core, the place of poetry’s own essence.

Research about fieldwork with 133 health professionals from different hospitals in Buenos Aires city about both functional and disfunctional discomfort perceived and expressed by them. Risk factors/items described are: work in isolation, naturalizing of discomfort, overload, overadaptation, inappropriate relieving methods: tobacco, alcohol, too much or insufficient food, anxiety, self - carelessness, both physical or emotional, unawareness of their rights as workers. Work in hospitals also provides satisfaction. Some questions and reflexions are stated and a minimum decalogue of measures to prevent and promote health in hospital workers is proposed.

Se estudia la auto-interaccion de un modo normal de Rossby en una cuenca rectangular por medio de un modelo analítico y uno numérico. La auto-interacción a primer orden produce un forzamiento transitorio con el doble de la frecuencia del modo y un forzamiento estacionario. El forzamiento estacionario tiene como respuesta la presencia de dos giros: uno anticiclónico en la parte norte de la cuenca y el otro ciclónico en la parte sur. La respuesta directa al forzamiento transitorio no satisface la condición a la frontera de flujo normal cero en las paredes meridionales. El fluido se ajusta generando ondas de Rossby, de tal forma que la suma de la función corriente de estas ondas (solución homogénea) y la función corriente forzada resulte nula en las paredes. Entre las componentes de la solución perturbativa a primer orden, la que tiene mayor importancia es la solución estacionaria. Los términos advectivos juegan un papel decisivo en la circulación de la cuenca si ésta es relativamente pequeña; por el contrario, para cuencas grandes los términos alineales tienen poco peso. En los resultados del modelo numérico se aprecia un desfase en la función corriente respecto a la solución analítica, presumiblemente por el efecto de la discretización en el modelo numérico. La solución numérica alineal difiere apreciablemente de la solución analítica a primer orden conforme la amplitud de la condición inicial se incrementa, indicándonos que la solución analítica es válida para números de B-Rossby pequeños. No contiene

Foliar wetness plays an essential role in plant disease cycles and epidemic development yet no cost-effective leaf wetness sensors (LWSs) are available that could be deployed within large areas to better understand that role. Electronic LWSs comprise an artificial leaf and the electronic circuitry able to measure electrical impedance changes due to water film or drops on the leaf surface. We propose a simple, compact and low-cost electronic interface circuit (EIC) for artificial leaves based on capacitance changes. The circuit relies on the charge-transfer capacitive sensing method and it is implemented by a microcontroller unit (MCU), which offers computation and communication capabilities currently missing in commercial LWSs, This EIC can be used in custom and commercial artificial leaves hence suits studies that require a close emulation of particular plant leaves.

A new technique to measure a capacitor or a capacitive sensor by means of a direct sensor-to-microcontroller interface circuit that does not need a calibration capacitor is proposed. Basically, the measurement process consists of three consecutive steps of charge, discharge and charge of the capacitor under test. A non-linear equation is obtained and solved that is dependent only on known circuit parameters. Experimental results show that it is possible to measure a wide range of capacitor values with a maximum deviation of 2% from the reference value, and that temperature changes from 18 to 70°C yield relative errors below 0.1%. For the lowest measured capacitor range (33 pF-4.7 nF) the uncertainty holds below 1 pF which enables measurement of commercially available capacitive sensors. The main advantage of the proposed technique is cost and space reduction of the final design.

Differential circuits are assumed to reject common-mode noise yet no parameter is available to describe that rejection as the Common Mode Rejection Ratio (CMRR) applies only to deterministic signals, not to random noise. We propose a model and a method to analyze the contribution of the input common-mode electronic noise to the output voltage noise of differential circuits. The analysis shows that the same parameter-matching conditions that improve the CMRR determine common-mode noise rejection but CMRR is more sensitive to mismatching. For example, a low-frequency CMRR as low as 8 dB implies that more than 82% of common-mode noise is rejected. Thus, often only differential-mode noise is relevant. However, if the equivalent input current noise sources predominate over equivalent input voltage noise sources, cross-correlation between them partially yields common-mode noise that will also be rejected. We also propose a simple test that yields an estimate of that correlation.