Introducción al control de calderas de biomasa en sistemas de calefacción

Este trabajo es el punto de partida de un estudio más amplio cuyo objetivo final es el diseño de un sistema de control que permita optimizar el proceso de combustión e intercambio de calor en una caldera de biomasa. Este control tendrá que corregir los parámetros del sistema para adaptarse a las características del combustible que se introduzca a la cámara de combustión. El desarrollo de una caldera de este tipo está motivado tanto por la utilización de recursos renovables como son los biocombustibles como por ser rentables por sí mismas en muchos casos. Por contra, los combustibles procedentes de la biomasa son exigentes y muy poco homogéneos, y precisan dispositivos sofisticados. La certificación de pellets y astillas, que son los combustibles para los que se ha pensado en un inicio el futuro diseño de caldera, presentan pese a ello una gran variabilidad en sus características de unas partidas a otras. Existen ya numerosas marcas, muchas de ellas austriacas, que comercializan calderas de gran calidad. Estudiando varias de ellas se comprenden los elementos básicos que las componen y que servirán para comenzar con el diseño de un prototipo. Los dos elementos básicos que componen una caldera de este tipo son la cámara de combustión y el intercambiador de calor. Para facilitar el análisis se puede realizar un estudio termodinámico de cada una de estas partes por separado pero el funcionamiento no se puede entender sin la construcción de un modelo completo que incluya a ambas. Teniendo en cuenta los numerosos factores que afectan al funcionamiento de una caldera y su versatilidad de adaptación a numerosas instalaciones se propone el diseño del control de una caldera de 200 KW, policombustible, con parrilla móvil, intercambiador vertical y limpieza automática de tubuladores. Entre los distintas posibilidades de control que se desarrollará en el futuro se optará por un control predictivo combinado con una sensorización avanzada que permita alcanzar los objetivos finales. Se construyó un modelo simplificado con dos tubos del intercambiador con Ansys Fluent y se realizaron varios experimentos que permitieron identificar modelos de comportamiento. La relación de la temperatura de salida del agua respecto a la de entrada se identificó como un sistema de segundo orden. La de la temperatura de salida del agua respecto a la de humos con uno de tercer orden. Este análisis y la identificación de modelos en discreto se realizó con programas escritos en lenguaje Python.Departamento de Ingeniería de Sistemas y AutomáticaMáster en Ingeniería Industria

Conotoxin Diversity in the Venom Gland Transcriptome of the Magician’s Cone, Pionoconus magus

The transcriptomes of the venom glands of two individuals of the magician’s cone, Pionoconus magus, from Okinawa (Japan) were sequenced, assembled, and annotated. In addition, RNA-seq raw reads available at the SRA database from one additional specimen of P. magus from the Philippines were also assembled and annotated. The total numbers of identified conotoxin precursors and hormones per specimen were 118, 112, and 93. The three individuals shared only five identical sequences whereas the two specimens from Okinawa had 30 sequences in common. The total number of distinct conotoxin precursors and hormones for P. magus was 275, and were assigned to 53 conotoxin precursor and hormone superfamilies, two of which were new based on their divergent signal region. The superfamilies that had the highest number of precursors were M (42), O1 (34), T (27), A (18), O2 (17), and F (13), accounting for 55% of the total diversity. The D superfamily, previously thought to be exclusive of vermivorous cones was found in P. magus and contained a highly divergent mature region. Similarly, the A superfamily alpha 4/3 was found in P. magus despite the fact that it was previously postulated to be almost exclusive of the genus Rhombiconus. Di erential expression analyses of P. magus compared to Chelyconus ermineus, the only fish-hunting cone from the Atlantic Ocean revealed that M and A2 superfamilies appear

The genome of the venomous snail Lautoconus ventricosus shed light on the origin of conotoxin diversity

Background: Venoms are deadly weapons to subdue prey or deter predators that have evolved independently in many animal lineages. The genomes of venomous animals are essential to understand the evolutionary mechanisms involved in the origin and diversification of venoms. Results: Here, we report the chromosome-level genome of the venomous Mediterranean cone snail, Lautoconus ventricosus (Caenogastropoda: Conidae). The total size of the assembly is 3.59 Gb; it has high contiguity (N50 = 93.53 Mb) and 86.6 Mb of the genome assembled into the 35 largest scaffolds or pseudochromosomes. On the basis of venom gland transcriptomes, we annotated 262 complete genes encoding conotoxin precursors, hormones, and other venom-related proteins. These genes were scattered in the different pseudochromosomes and located within repetitive regions. The genes encoding conotoxin precursors were normally structured into 3 exons, which did not necessarily coincide with the 3 structural domains of the corresponding proteins. Additionally, we found evidence in the L. ventricosus genome for a past whole-genome duplication event by means of conserved gene synteny with the Pomacea canaliculata genome, the only one available at the chromosome level within Caenogastropoda. The whole-genome duplication event was further confirmed by the presence of a duplicated hox gene cluster. Key genes for gastropod biology including those encoding proteins related to development, shell formation, and sex were located in the genome. Conclusions: The new high-quality L. ventricosus genome should become a reference for assembling and analyzing new gastropod genomes and will contribute to future evolutionary genomic studies among venomous animals.This work was funded by the Spanish Ministry of Science and Innovation (CGL2016-75255-C2-1-P [AEI/FEDER, UE] and PID2019-103947GB-C22/AEI/10.13039/501100011033 to R.Z.; BES-2017-081195 to J.R.P.-B.; BES-2014-069575 to S.A.; IJCI-2016-29566 to I.I.). I.I. acknowledges the support from the European Research Council during the latest stages of the project (Grant Agreement No. 852725; ERC-StG "TerreStriAL" to Jan de Vries, University of Goettingen)

Comparative Venomics of the Cryptic Cone Snail Species Virroconus ebraeus and Virroconus judaeus

The venom duct transcriptomes and proteomes of the cryptic cone snail species Virroconus ebraeus and Virroconus judaeus were obtained and compared. The most abundant and shared conotoxin precursor superfamilies in both species were M, O1, and O2. Additionally, three new putative conotoxin precursor superfamilies (Virro01-03) with cysteine pattern types VI/VII and XVI were identified. The most expressed conotoxin precursor superfamilies were SF-mi2 and M in V. ebraeus, and Cerm03 and M in V. judaeus. Up to 16 conotoxin precursor superfamilies and hormones were differentially expressed between both species, and clustered into two distinct sets, which could represent adaptations of each species to different diets. Finally, we predicted, with machine learning algorithms, the 3D structure model of selected venom proteins including the differentially expressed Cerm03 and SF-mi2, an insulin type 3, a Gastridium geographus GVIA-like conotoxin, and an ortholog to the Pionoconus magus ω-conotoxin MVIIA (Ziconotide)

Taxonomic revision of West African cone snails (Gastropoda: Conidae) based upon mitogenomic studies: implications for conservation

In the last few years, a sharp increase in the number of descriptions of new species of West African cone snails, particularly from the Cabo Verde Archipelago, has taken place. In previous studies, we used mitogenome sequences for reconstructing robust phylogenies, which comprised in total 120 individuals representing the majority of species (69.7%) described from this biogeographical region (except Angolan endemics) and grouped into seven genera within the family Conidae. Here, we add another 12 individuals representing endemic species that were missing in the previous studies. We use the phylogenies to identify monophyletic groups and a genetic divergence threshold (0.2% uncorrected p distance) to determine the number of valid species. As a result, the number of valid West African cone species could be drastically reduced to at least 40%, indicating that some recent poor-quality descriptions loosely based on phenotypic characters prone to convergence such as the shape and color patterns of the shell have contributed substantially to taxonomic inflation. Several previously accepted species with a reduced geographical distribution now become phenotypic forms of the remaining valid species, which increase their distribution ranges. In contrast, several cryptic species are now uncovered and described. For instance, Africonus insulae sp. nov. and Kalloconus canariensis sp. nov. are hereby introduced as new species. A detailed systematic account with illustrations and relevant information is presented. Lectotypes are designated for Conus trochulus and Conus irregularis, and neotypes for Conus crotchii and Conus diminutus. According to our results, it is strongly recommended that any future introduction of new taxa names for cone snails from West Africa should be supported by molecular and/or anatomical rather than exclusively shell morphological data. The taxonomic decisions here taken have direct implications for conservation and will eventually require re-evaluation of the Red List risk status of an important number of species

Comparative Venomics of the Cryptic Cone Snail Species Virroconus ebraeus and Virroconus judaeus

The venom duct transcriptomes and proteomes of the cryptic cone snail species Virroconus ebraeus and Virroconus judaeus were obtained and compared. The most abundant and shared conotoxin precursor superfamilies in both species were M, O1, and O2. Additionally, three new putative conotoxin precursor superfamilies (Virro01-03) with cysteine pattern types VI/VII and XVI were identified. The most expressed conotoxin precursor superfamilies were SF-mi2 and M in V. ebraeus, and Cerm03 and M in V. judaeus. Up to 16 conotoxin precursor superfamilies and hormones were differentially expressed between both species, and clustered into two distinct sets, which could represent adaptations of each species to different diets. Finally, we predicted, with machine learning algorithms, the 3D structure model of selected venom proteins including the differentially expressed Cerm03 and SF-mi2, an insulin type 3, a Gastridium geographus GVIA-like conotoxin, and an ortholog to the Pionoconus magus ω-conotoxin MVIIA (Ziconotide).This research was funded by the Spanish Ministry of Science and Innovation (CGL2016-75255-C2-1-P [AEI/FEDER, UE] and PID2019-103947GB-C22/AEI/10.13039/501100011033 to R.Z.; BES-2017-081195 to J.R.P-B) and by the Junta de Andalucía (PAIDI FQM188) to M.J.T.Peer reviewe

Seasonal changes in the physiological activity of regeneration under a natural light gradient in a Pinus pinea regular stand

Seasonal courses of chlorophyll a fluorescence, gas exchange parameters and water status, joined to environmental variables, were measured in four age classes of stone pine (Pinus pinea L.) natural regeneration, selected within a natural light gradient in order to cover the whole range of incident light detected within a stone pine regular stand throughout 2007 and 2008. Selection of light conditions was based a priori on the distance of seedlings to the parent trees, expressed by crown radius distances. One-year old seedlings were worse acclimated to the extreme drought conditions recorded in summer (especially in 2008), showing lower predawn and midday Fv/Fm values, slightly lower photosynthetic rates at midday, lower Phi PSII values, lower water potentials (Psi(pd) and Psi(min)), and high mortality (90%). The oldest seedlings (class 4, 51-200 cm high), although they do not experience the lowest Psi(min). in July 2008, were not able to maintain a positive carbon gain at midday, even showing the lowest photosynthetic rates. However, they rapidly recovered once the climatic conditions were softened in early autumn. During late autumn low Fv/Fm values were found especially in one-year old seedlings, indicating that maximal photochemical efficiency of PSII is sensitive to the autumn temperatures below cero recorded during both years. Thus, stone pine regeneration acclimates its physiology to the seasonal course of temperature and water availability, and this acclimation depended on age class. However, seedling physiology is only slightly affected by differences in light environment, probably related to the low variability recorded in GSF values (0.55 +/- 0.01), due to the low density of the stand. We suggest that such low stand densities cannot assure one-year old seedlings' survival, but are sufficient for older seedlings