Closing the residential energy loop: Grey-water heat recovery system for domestic hot water production based on heat pumps

[EN] Passive houses linked to more efficient heating and cooling technologies have been one of the focus in last years. However, to close the loop of the building sector, there is still one open source: wasted heat from grey water. This paper addresses the potentiality of the wasted heat from grey water as a heat source to produce domestic hot water (DHW) based on a heat pump system (HP). A heat pump optimized for these applications, a heat recovery heat exchanger and two variable volume storage tanks compose the system. The main objective of this work is to determine the potential recovery of the wasted heat in order to minimize the building energy consumption. Design guidelines of the components and the analysis of an optimum operation algorithm of the system have been performed in order to minimize CO2 emissions. In addition, an evaluation of the potential heat recovery of the wasted heat is included. As an example, that methodology has been applied to 20 dwellings. Based on that case, the obtained results demonstrate that by recovering 80% of the available recovery heat, the total demand of DHW is satisfied with high levels of comfort and efficiency.Part of the work presented was carried out by Estefania Hervas Blasco with the financial support of a PhD scholarship from the Spanish government SFPI1500 x074478XV0. The authors would like also to acknowledge the Spanish `Ministerio de Economia Y Competitividad', through the project "Maximizacion de la Eficiencia Y Minimizacion del Impacto Ambiental de Bombas de Calor Para la Descarbonizacion de la Calefaccion/ACS EN Los Edificios de Consumo Casi Nulo" with the reference ENE2017-83665-C2-1-P for the given support.Hervás-Blasco, E.; Navarro-Peris, E.; Corberán, JM. (2020). Closing the residential energy loop: Grey-water heat recovery system for domestic hot water production based on heat pumps. Energy and Buildings. 216:1-15. https://doi.org/10.1016/j.enbuild.2020.109962S115216García-Álvarez, M. 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Exergy analysis on a heat pump working between a heat sink and a heat source of finite heat capacity rate

[EN] The optimum performance of a pure subcritical refrigeration cycle depends significantly on the temperature lift of the heat source and sink. Therefore, the maximization of the system efficiency has to be linked to them. This paper shows an exergy analysis of each heat pump component (condenser, evaporator, expansion valve and compressor) considering that the heat source and sink are not at constant temperature. The performed study shows the components with more possibilities for improvement. Based on this analysis, the optimization of cycle parameters like subcooling and superheat as a function of the external conditions have been done. In addition, this work has demonstrated that the components having a higher influence in the system irreversibility's depends significantly on the temperature lift of the secondary fluids. Finally, the obtained results show potentials improvements of the efficiency up to 23% if the system is able to operate in the optimal subcooling and superheat.Part of the results of this study were developed in the mainframe of the FP7 European project 'Next Generation of Heat Pumps workingwith natural fluids' (NxtHPG). Part of the work presented was carried by Miquel Pitarch with the financial support of a PhD scholarship from the Universitat Politecnica de Valencia. Part of the work presented was carried by Estefania Hervas-Blasco with the financial support of a Ph.D. scholarship from the Spanish government SFPI1500X074478XV. The authors would like also to acknowledge the Spanish 'MINISTERIO DE ECONOMIA Y COMPETITIVIDAD', through the Project ENE2017-83665-C2-1-P, "Maximizacion de la Eficiencia y Minimizacion del Impacto Ambiental de Bombas de Calor para la descarbonizacion de la calefaccion/ACS en los proximos edificios de consumo energetico casi nulo" for the given support.Pitarch, M.; Hervás-Blasco, E.; Navarro-Peris, E.; Corberán, JM. (2019). Exergy analysis on a heat pump working between a heat sink and a heat source of finite heat capacity rate. International Journal of Refrigeration. 99:337-350. https://doi.org/10.1016/j.ijrefrig.2018.11.044S3373509

Características citopatológicas del carcinoma de células acinares (CCA) de glándula salival: a propósito de cuatro observaciones

Objetivo: Presentar las características citopatológicas del carcinoma acinar (CCA), así como su correlación cito-histológica, comentando los problemas de diagnóstico diferencial de esta entidad en base a cuatro observaciones estudiadas mediante PAAF. Casos clínicos: Dos varones de 52 y 53 años, una mujer de 79 años, y una niña de 12 años que presentaron tumoraciones localizadas en territorio parotídeo (casos 1, 2 y 4), y a nivel laterocervical (caso 3). En tres pacientes, la PAAF fue, junto a los estudios de imagen, la primera aproximación diagnóstica; correspondiendo el caso 3 a una punción de adenopatías laterocervicales metastásicas en una paciente con antecedentes de CCA de parótida. Hallazgos citológicos: Las extensiones citológicas mostraron abundante celularidad tumoral dispuesta en pequeñas placas monocapa, formando estructuras acinares, o como células aisladas. Es de destacar la abundancia de núcleos desnudos en el fondo de los frotis, y la ausencia de grasa y de epitelio ductal. Las células poseían núcleos monomorfos redondeados u ovales, nucleólo poco evidente y abundante citoplasma granular o finamente vacuolado. Discusión: La PAAF proporciona información esencial en la actuación diagnóstico-terapeútica de las tumoraciones de la glándula salival, resultando esta metodología muy sensible en su eficacia diagnóstica. La identificación de los CCA frecuentemente presenta dificultades, debido a la gran similitud citológica de las células tumorales con el componente acinar normal propio de la glándula salival. El diagnóstico diferencial se plantea, fundamentalmente, con carcinomas de células claras, con carcinomas mucoepidermoides, con el tumor de Warthin y con los oncocitomas. Nuestras observaciones confirman la validez de la PAAF en una primera aproximación diagnóstica de estas lesiones tumorales accesibles a la punción directa.Objective: To present the cytopathological characteristics of acinic cell carcinoma (ACC) as well as its cyto-histological correlation, commenting on the differential diagnostic problems of this entity based on four observations studied using fine-needle aspiration biopsy (FNAB). Clinical Cases: Two males of 52 and 53 years of age, one 79 year-old woman and a girl of 12 years of age, who presented tumors located in the parotid area (cases 1, 2 and 4) and at the laterocervical level (case 3). In 3 patients, the FNAB was, together with the image studies, the first diagnostic indication; case 3 corresponding to a puncture of metastatic laterocervical adenopathies in a patient with a history of parotid ACC. Cytological findings: The cytologic smears revealed abundant tumoral cellularity arranged in small monolayered sheets, forming acinar structures or isolated cells. The abundance of bare nuclei at the background of the smears, and the absence of adipose tissue and ductal epithelium are highlighted. The cells possessed round or oval monomorphic nuclei, few nucleoli and abundant granular or finely vacuolate cytoplasm. Discussion: FNAB provides essential information on the diagnostic- therapeutic management of salivary gland tumors; this methodology is highly sensitive in its diagnostic efficacy. The diagnosis of ACCs frequently presents difficulties, owing to the great cytologic similarity of the tumor cells with the normal acinar component of the salivary gland. The differential diag-nosis is considered, fundamentally, with clear cell carcinomas, mucoepidermoid carcinomas, Warthin's tumor, and oncocytomas. Our observations confirm the validity of FNAB in a first diagnostic approximation for those lesions accessible to direct puncture

Diagnóstico citológico de las recidivas tumorales de ameloblastoma: presentación de dos casos clínicos

Introducción: Los ameloblastomas son los tumores odontogénicos más frecuentes del maxilar. A pesar de su aspecto citohistológico de benignidad, se comportan como tumores invasivos, recidivantes y con posibilidad de metastatizar. La P.A.A.F. es una prueba rápida e incruenta que proporciona un diagnóstico prequirúrgico evitando, en ocasiones, tomas biópsicas destinadas al diagnóstico. Presentamos las características citológicas de dos casos de recidiva yugal de ameloblastoma de rama mandibular diagnosticados por PAAF, así como su correlación citohistológica. Casos clínicos: Dos pacientes, una mujer de 36 años y un varón de 62 años, que acuden por tumoración mandibular de escasos meses de evolución. En ambos casos, la primera aproximación diagnóstica fue junto a los estudios radiológicos el estudio histológico de la masa tumoral. Tras la extirpación terapeútica, ambos casos recidivaron. El diagnóstico de las recidivas fue establecido citológicamente mediante PAAF. Las extensiones citológicas mostraron un fondo granular con aislados macrófagos y células multinucleadas gigantes y una abundante celularidad epitelial de aspecto basaloide dispuesta en grupos cohesivos configurando imágenes de empalizada periférica, así como pequeños grupos de células de metaplasia escamosa. Discusión: La PAAF se considera como un método diagnóstico rápido, incruento y fiable en el diagnóstico del ameloblastoma. La citología de estos tumores revela los componentes de la lesión que, en general, son suficientes para llegar al diagnóstico de ameloblastoma, especialmente en casos de recidiva.Introduction: Ameloblastomas are the most frequent odontogenic tumors of the maxilla. In spite of their benign cytohistological appearance, they behave as invasive recurring tumors, with the possibility of metastasis. FNAB is a rapid, bloodless test that provides a pre-surgical diagnosis, thus, on occasions avoiding the need for diagnostic biopsies. We present the cytological characteristics of two cases of jugal recurrences of mandibular ameloblastomas diagnosed by FNAB, as well as their cytohistological correlation. Clinical cases: Two patients, a 36-year-old woman, and a 62- year-old male who both attended with mandibular swelling of a few months evolution. In both cases the first diagnostic approximation was the histological study of the tumoral mass, together with the radiological studies. Following therapeutic extirpation both cases recurred. The diagnosis of the recurrences was established cytologically by means of FNAB. The cytologic smears revealed a granular background with isolated macrophages and giant multinucleate cells and an abundant epithelial cellularity of basaloid appearance arranged in cohesive groups forming images of peripheral palidasing, as well as small groups of squamous metaplastic cells. Discussion: FNAB is considered to be a rapid, bloodless and reliable method for the diagnosis of ameloblastoma. The cytology of these tumors reveals components of the lesion that, in general, are sufficient for the diagnosis of ameloblastoma, especially in cases of recurrence

Memetic Evolutionary Multi-Objective Neural Network Classifier to Predict Graft Survival in Liver Transplant Patients

In liver transplantation, matching donor and recipient is a problem that can be solved using machine learning techniques. In this paper we consider a liver transplant dataset obtained from eleven Spanish hospitals, including the patient survival or the rejection in liver transplantation one year after the surgery. To tackle this problem, we use a multi-objective evolutionary algorithm for training generalized radial basis functions neural networks. The obtained models provided medical experts with a mathematical value to predict survival rates allowing them to come up with a right decision according to the principles of justice, efficiency and equit

The singular properties of photosynthetic cytochrome c 550 from the diatom Phaeodactylum tricornutum suggest new alternative functions

Cytochrome c 550 is an extrinsic component in the luminal side of photosystem II (PSII) in cyanobacteria, as well as in eukaryotic algae from the red photosynthetic lineage including, among others, diatoms. We have established that cytochrome c 550 from the diatom Phaeodactylum tricornutum can be obtained as a complete protein from the membrane fraction of the alga, although a C-terminal truncated form is purified from the soluble fractions of this diatom as well as from other eukaryotic algae. Eukaryotic cytochromes c 550 show distinctive electrostatic features as compared with cyanobacterial cytochrome c 550 . In addition, co-immunoseparation and mass spectrometry experiments, as well as immunoelectron microscopy analyses, indicate that although cytochrome c 550 from P. tricornutum is mainly located in the thylakoid domain of the chloroplast – where it interacts with PSII –, it can also be found in the chloroplast pyrenoid, related with proteins linked to the CO 2 concentrating mechanism and assimilation. These results thus suggest new alternative functions of this heme protein in eukaryotes.Ministerio de Economía, Industria y Competitividad BIO2015-64169-PJunta de Andalucía PAIDI BIO-02

The photosynthetic cytochrome c550 from the diatom Phaeodactylum tricornutum

The photosynthetic cytochrome c550 from the marine diatom Phaeodactylum tricornutum has been purified and characterized. Cytochrome c550 is mostly obtained from the soluble cell extract in relatively large amounts. In addition, the protein appeared to be truncated in the last hydrophobic residues of the C-terminus, both in the soluble cytochrome c550 and in the protein extracted from the membrane fraction, as deduced by mass spectrometry analysis and the comparison with the gene sequence. Interestingly, it has been described that the C-terminus of cytochrome c550 forms a hydrophobic finger involved in the interaction with photosystem II in cyanobacteria. Cytochrome c550 was almost absent in solubilized photosystem II complex samples, in contrast with the PsbO and Psb31 extrinsic subunits, thus suggesting a lower affinity of cytochrome c550 for the photosystem II complex. Under iron-limiting conditions the amount of cytochrome c550 decreases up to about 45% as compared to iron-replete cells, pointing to an iron-regulated synthesis. Oxidized cytochrome c550 has been characterized using continuous wave EPR and pulse techniques, including HYSCORE, and the obtained results have been interpreted in terms of the electrostatic charge distribution in the surroundings of the heme centre

The photosynthetic cytochrome c550 from the diatom Phaeodactylum tricornutum

The photosynthetic cytochrome c550 from the marine diatom Phaeodactylum tricornutum has been purified and characterized. Cytochrome c550 is mostly obtained from the soluble cell extract in relatively large amounts. In addition, the protein appeared to be truncated in the last hydrophobic residues of the C-terminus, both in the soluble cytochrome c550 and in the protein extracted from the membrane fraction, as deduced by mass spectrometry analysis and the comparison with the gene sequence. Interestingly, it has been described that the C-terminus of cytochrome c550 forms a hydrophobic finger involved in the interaction with photosystem II in cyanobacteria. Cytochrome c550 was almost absent in solubilized photosystem II complex samples, in contrast with the PsbO and Psb31 extrinsic subunits, thus suggesting a lower affinity of cytochrome c550 for the photosystem II complex. Under iron-limiting conditions the amount of cytochrome c550 decreases up to about 45% as compared to iron-replete cells, pointing to an iron-regulated synthesis. Oxidized cytochrome c550 has been characterized using continuous wave EPR and pulse techniques, including HYSCORE, and the obtained results have been interpreted in terms of the electrostatic charge distribution in the surroundings of the heme centre.España, MINECO BIO2012-35271, BIO2015-64169-P, MAT2011-23861 and CTQ2015-64486-

The photosynthetic cytochrome c 550 from the diatom Phaeodactylum tricornutum

The photosynthetic cytochrome c550 from the marine diatom Phaeodactylum tricornutum has been purified and characterized. Cytochrome c550 is mostly obtained from the soluble cell extract in relatively large amounts. In addition, the protein appeared to be truncated in the last hydrophobic residues of the C-terminus, both in the soluble cytochrome c550 and in the protein extracted from the membrane fraction, as deduced by mass spectrometry analysis and the comparison with the gene sequence. Interestingly, it has been described that the C-terminus of cytochrome c550 forms a hydrophobic finger involved in the interaction with photosystem II in cyanobacteria. Cytochrome c550 was almost absent in solubilized photosystem II complex samples, in contrast with the PsbO and Psb31 extrinsic subunits, thus suggesting a lower affinity of cytochrome c550 for the photosystem II complex. Under iron-limiting conditions the amount of cytochrome c550 decreases up to about 45% as compared to iron-replete cells, pointing to an iron-regulated synthesis. Oxidized cytochrome c550 has been characterized using continuous wave EPR and pulse techniques, including HYSCORE, and the obtained results have been interpreted in terms of the electrostatic charge distribution in the surroundings of the heme centre.This work was supported by the Spanish Ministry of Economy and Competitiveness (BIO2012-35271, BIO2015-64169-P, MAT2011-23861 and CTQ2015-64486-R) the Andalusian Government (PAIDI BIO-022) and the Aragón Government (Grupo consolidado B-18). All these grants were partially financed by the EU FEDER ProgramPeer reviewe