189 research outputs found
Improved heliostat field design for solar tower plants
No full textIn solar power tower (SPT) systems, selecting the optimum location of thousands of heliostats and the most profitable tower height and receiver size remains a challenge. Campo code is prepared for the detailed design of such plants in particular, the optimum layout, provided that the plant size is known. Therefore, less exhaustive codes, as DELSOL3, are also needed to perform preliminary parametric analysis that narrows the most economic size of the plant
Aedes (Bifidistylus) boneti Gil Collado
No full textAedes (Bifidistylus) boneti Gil Collado subspecies boneti Gil Collado, 1936 —original combination: Aedes (Aedimorphus) boneti. Distribution: Known only from the type locality, Isla de Bioko (Fernando Po), Equatorial Guinea (Gil Collado 1936). subspecies kumbae Chwatt, 1948 —original combination: Aedes (Aedimorphus) boneti s.sp. kumbae. Distribution: Republic of Cameroon (Chwatt 1948). The nominotypical subspecies was described from a single male from Rebola, Bioko Island, Equatorial Guinea. The island has an area of 2,017 km 2 and is 32 km from the coast of Cameroon (https://en.wikipedia.org/wiki/ Bioko; accessed 7 April 2022). Gil Collado credited F. W. Edwards for identifying the species as new, stating: “I must tender my thanks to J. W. Edwards [sic], who... examined the material... verifying my findings and alerting me to a new species of Aedimorphus, represented by a specimen it had been impossible for me to identify due to its somewhat deficient state of preservation [translated from the Spanish].” The male holotype is in the Museum, Madrid University School of Agriculture, Madrid, Spain. We used a published translation of the description from the Spanish along with the original article for this treatment. The description is detailed and accompanied by a drawing of a dorsal view of the head and appendages (antenna, maxillary palpus, proboscis) and a hindleg. The forelegs are not described, leaving the impression that they are missing. Damage to the specimen noted by the author included: “The scutellum has very wide whitish scales in its middle lobe, those from the sides [lateral lobes] having been removed... Anterior pronotum [antepronotum] has two groups of 5 to 6 bristles [setae]; the posterior [postpronotum], some 4, though in our specimen, they are somewhat destroyed…. Supra-alar scales are dark and numerous; those from the dorso-central area of our specimen have been torn off….” Our assumption is that characteristics of the cuticle (setae, scales, pollinosity, etc.) might be modified enough to render an accurate description problematical. Re-examination of the holotype is needed to be certain. Gil Collado also noted: “This species presents traits which closest approximate lamborni Edw. [the only other species now included in the subgenus Bifidistylus], in whose group they must be included because of their tarsal rings; however, in spite of the fact that the specimen’s [as in translation] hypopygium [genitalia] was destroyed in preparation, the coxa [gonocoxite] does not seem as pronounced as in that species...”. Gil Collado then compared boneti with lamborni Edwards, 1923a. To our knowledge the holotype of boneti is the only known specimen of this species. However, given the intense study of Anopheles and malaria control on Bioko (e.g. Cook et al. 2018), it is not surprising that species of other genera might have been overlooked, with the exception of the relatively recent invasive Aedes albopictus (Skuse, 1895) (Toto et al. 2003), and pest species of Culex (e.g. Fuseini et al. 2019). Gil Collado (1936) documented about 30 mosquito species on Bioko. All but Anopheles lloreti Gil Collado, 1936 are also found on mainland Africa. The type of An. lloreti is perhaps the only specimen of this species as well. An attribute that to us stands out as unique is paired spots of erect black scales on the vertex of the head. “Head with a broad vertical zone of narrow, reclining, white scales, among which numerous dark standing scales appear; on each side there is a rounded blotch of dark scales, which in turn, has a lateral region of white, narrow, reclining scales, and in the same posterior angle of the eyes there is a small dark spot.” These spots are not noted in Ae. lamborni, but they are present in subspecies kumbae. Subspecies kumbae was described from Kumba, British Cameroons [Republic of Cameroon] by Chwatt (1948). The type localities of kumbae and the type form are 117 km apart (determined by David Pecor on 04/07/2022, https:// arcg.is/CqOTz1) and, as stated above, the island and mainland are separated by 32 km of ocean. The description and illustrations of kumbae are detailed and based on a series of specimens: 10 larvae, three pupal exuviae and two adult males with dissected genitalia mounted with the associated pupal exuviae. Of these, Townsend (1990) found two males and six larvae in the Natural History Museum, London. Chwatt (1948) apparently relied on the description of the male of boneti to compare subspecies kumbae with boneti since there is no indication that he examined the holotype of boneti. Hopkins (1952) included boneti in a key but reproduced the description and larval illustration of subspecies kumbae to represent boneti. For purposes of comparison, therefore, we only have the descriptions of the adult male of each nominal form. The following are comments and characters that Chwatt (1948) used to justify giving kumbae subspecies status: “In Edwards’s (1941) key to the Ethiopian species of Aëdes the two male adults [the two specimens used to describe subspecies kumbae] would run down to A. boneti Gil Collado, described in 1936 from a single damaged male captured on the Island of Fernando Po. The similarity between the two adults described above and the original description of A. boneti is considerable. Nevertheless, there are several notable differences―mainly the more extensive, rather differently shaped, dark scaling of the head, the pale (instead of golden) colour of the investiture of the mesonotum, the presence of prescutellar rows of scales, the scaling of the abdominal sternites [sterna], the presence of small pale apical spots on the dorsal surface of the femora, the presence of basal white spots on the costa, and the markings of the last hind tarsal segments.” We itemized the above characters and extracted text from the original descriptions of kumbae and boneti, i.e. from Gil Collado (1948) and Chwatt (1936), respectively, as follow. “...the more extensive, rather differently shaped, dark scaling of the head...”. — kumbae: “Occiput with two, dark, dorsolateral, conspicuous, oval or comma-shaped spots, formed by dark-brown upright forked scales. The remainder of the upright scales pale. Prominent dark-brown bare vertical area along the median suture [coronal suture].” [large dark spots illustrated] — boneti: “Head with a broad vertica1 zone of narrow, reclining, white scales, among which numerous dark standing scales appear; on each side there is a rounded blotch of dark scales, which in turn, has a lateral region of white, narrow, reclining scales, and in the same posterior angle of the eyes there is a small dark spot.” [dorsolateral and lateral dark spots evident in the illustration] We do not interpret these two descriptions to be substantially different, in addition the illustrations of the heads are quite similar, especially the two large dark spots of erect scales. “...the pale (instead of golden) colour of the investiture of the mesonotum [scutum]...”. — kumbae: “Mesonotum covered with a mixture of narrow, curved, dark-brown and pale scales...”. — boneti: “Mesonotum, except for its anterior edge, has sparse gold scales mixed with wider black scales.” Pale scales versus sparse gold scales could be explained by differences in lighting used for the observations. “...the presence of prescutellar rows of scales... ”. — kumbae: “...dark-brown and pale scales, the latter broader on the anterior and anterolateral borders [of the scutum] and broad and flat around the prescutellar bare area.” — boneti: “In the middle region, in front of the scutellum, there are some white scales.” Neither description mentions rows of scales in front of the scutellum or provides a clear distinction between the two. “...the scaling of the abdominal sternites [sterna]...”. — kumbae: “Sternites covered almost entirely with broad flat pale scales.” — boneti: Not noted. No applicable difference. “...the presence of small pale apical spots on the dorsal surface of the femora...”. — kumbae: “Fore femora dark, with a paler basal ventral surface and a few white scales at the distal end of the dorsal surface; middle femora similar, with a rather more extensive pale ventral area; hind femora dark on the dorsal side, except for a white distal spot, mainly pale on the ventral side...”. — boneti: Forefemur not noted. “Legs II [midlegs]: femora with their anterior and dorsal surfaces dark, and the posterior surface completely pale at the base, this coloration narrowing progressively toward the apex, where there is only a single white ventral line…”. “Legs III [hindlegs] with predominantly white femora, and a narrow black dorsal strip, while the anterior face is peppered with abundant dark scales.” The apical pale femoral spot in kumbae is described only for the hindfemur. The illustration of the hindleg of boneti does not show an apical spot. We think this remains ambiguous pending comparison of the holotypes of the two nominal forms. “...the presence of basal white spots on the Costa... ”. — kumbae: “Wings with scales dark and a small basal patch of pale scales on the lower and anterior surface of the costa.” — boneti: “The wing scales are dark, and even blackish over C and R 1.” A few pale scales at the base of the costa can be variable. “...and the markings of the last hind tarsal segments [which markings not stated].” — kumbae: “hind tarsi... first segment [tarsomere 1] dark, with an apical white band, second with one basal and one apical white band, the latter about twice the length of the former, third with one apical and one basal narrow band. The fourth tarsus [tarsomere 4] shows some variation: in one specimen it has a dark median band, while in the other the dark scales form only a narrow longitudinal line on the apical half of the lower surface. In both specimens the fifth tarsus [tarsomere 5] is white but has a similar dark line on the lower surface.” — boneti: “The metatarsi [hindtarsomeres 1] are black, with bristles of the same color, and a white spot at their apices which is a little longer than their width. The 2nd article [tarsomere 2] has a narrow pale basal zone, and another at its apex which is two and a half times its thickness; the 3rd with an apical ring the same as the 2nd and one at the base which is a little greater than its diameter. The 4th is white with a middle dark zone of one fourth its total length, and the 5th, completely white.” [roughly matches the illustration of the hindleg] No defining differences are given. Chwatt (1948) wrote: “This Aedimorphus is described here under the provisional name of A. boneti s.sp. kumbae. Should the still unknown larva of A. boneti prove to be different from the one described above, A. boneti s.sp. kumbae will have to be treated as a new species, A. (Aedimorphus) kumbae.” Our interpretation is that when kumbae was described, no significant characters were given to distinguish the two nominal taxa, and we therefore treat kumbae is a synonym of boneti until proven otherwise: kumbae Chwatt, 1948, junior subjective synonym of Aedes (Bifidistylus) boneti Gil Collado, 1936 . Should the larvae be found, the larva of kumbae possesses some potentially unique characteristics for diagnosis, such as an array of variously shaped spines on the siphon and a dense patch of comb scales. The nominal subspecies kumbae, which is listed as a species in the Encyclopedia of Life, must be removed from the list of valid species of Aedes.Published as part of Harbach, Ralph E. & Wilkerson, Richard C., 2023, The insupportable validity of mosquito subspecies (Diptera: Culicidae) and their exclusion from culicid classification, pp. 1-184 in Zootaxa 5303 (1) on pages 20-22, DOI: 10.11646/zootaxa.5303.1.1, http://zenodo.org/record/804334
Photolysis of m-phenylene-bis(Chlorodiazirine)+2-vinylpyridine: does an indolizine chromophore inhibit the photolysis of a diazirine?
No full textThe photolysis of m-phenylene-bis(chlorodiazirine) in the presence of 2-vinylpyridine (VP) yields the m-phenylene-bis(indolizine) by a mechanism involving two consecutive photoreactions. Photolysis of a first diazirine ring generates a carbene which reacts with 2-VP to give, via a sequence of fast thermal reactions, a first product including both the indolizine and the chlorodiazirine moieties. Although in the lowest excited singlet state of the primary product, the excitation is localized on the indolizine unit, the photolysis of this product induces the decomposition of the second diazirine ring to give a second carbene which yields the final product via the same sequence of reactions: formation of a 2-vinylpyridinium ylide, cyclization and elimination of HCl. Analysis of the absorption and fluorescence spectra indicates that an upper excited singlet state, with the excitation localized on the diazirine ring, is only a few kJ/mol above S-1. It can therefore be populated by thermal activation of S-1 so that there is, seemingly, an endothermic intramolecular energy transfer from the indolizine moiety to the diazirine ring. (C) 2003 Elsevier B.V. All rights reserved.PT: J; CR: BATTINO R, 1983, J PHYS CHEM REF DATA, V12, P163 BONNEAU R, UNPUB J PHYS CHEM DESVERGNE JP, 2003, PHOTOCH PHOTOBIO SCI, V2, P289 GOULD IR, 1985, TETRAHEDRON, V41, P1987 GRAHAM WH, 1965, J AM CHEM SOC, V87, P4396 LERNER DA, 1977, J PHYS CHEM-US, V81, P12 LIU MTH, 1994, INT J CHEM KINET, V26, P1179 LIU MTH, 2001, 9 KYUSH INT S PHYS O MUROV SL, 1973, HDB PHOTOCHEMISTRY, P56 TOMIOKA H, 1993, CHEM LETT, P1291 VELAPOLDI RA, 1980, 26064 NAT BUR STAND ZUEV P, 1993, J AM CHEM SOC, V115, P3788 ZUEV PS, 1994, J ORG CHEM, V59, P2267; NR: 13; TC: 1; J9: J PHOTOCHEM PHOTOBIOL A-CHEM; PG: 8; GA: 741YRSource type: Electronic(1
La recepción de la obra de Jean-Baptiste Say en España: la teoría económica del empresario
No full textEste trabajo analiza la difusión de la teoría del empresario de Jean-Baptiste Say
en España, como último eslabón de una línea de pensamiento que tiene su origen
en Richard Cantillon. Se prueba que la particularidad de este autor es su gran difusión
en el siglo XIX español –siendo uno de los más traducidos– y la escasa
influencia de su teoría económica del empresario. Explicamos las razones de una
paradoja que deja sin fundamentos teóricos a cualquier política económica destinada
al desarrollo del tejido empresarial nacional. Son presentados los mecanismos
de difusión, tanto directos, por medio de traducciones, como indirectos, por
medio de autores españoles que pudieron difundir esta teoría de la función empresarial.
Nos interesa conocer la recepción por parte de los autores españoles de
la teoría del empresario de Say, determinar su grado de comprensión, de interpretación
en relación con la realidad nacional, de revisión teórica, e incluso conocer
si la fuente real de la idea a transmitir es el propio autor o alguna otra.This paper illustrates the spread of Jean-Baptiste Say’s entrepreneur theory in Spain –a last contribution within the French tradition in which Richard Cantillon and A. R. J. Turgot were predecessors. We attempt to demonstrate that this is a special case, because, even though J. B. Say was the most important author from a publishing point of view, his economic theory of entrepreneurship had very little influence. The spread of economic ideas by way of translation and Spanish authors which employed J. B. Say’s economic theory, give possible explanations to a
paradox which had left economic policy without a theoretical reference. We analyse how Say’s entrepreneur theory was received among Spanish authors in the 19th century, its degree of comprehension and the analytical additions made, and attempt to identify the real source of transmission
Spectroscopic, kinetic, and structural properties of rotamers of the 2-vinylpyridinium ylide of phenylchlorocarbene
No full textThe analysis of the time-resolved UV-vis absorption spectra of the 2-vinylpyridinium ylide of phenylchlorocarbene, measured by laser-flash photolysis, indicates the existence of two rotamers of this species. The absorption spectrum, rise time, and decay time of each rotamer were determined by a global analysis method. The kinetic analysis of the results indicates an interconversion between the rotamers and a large difference between their rates of cyclization. The observed rotamerism involves a rotation of the vinyl pyridine with respect to the carbene, the two rotamers being differentiated by the fact that the vinyl group faces either the chlorine or the phenyl groups of the carbene. Calculations of the absorption spectra and enthalpies of formation of numerous possible structures indicate that the 100-nm difference between the wavelengths of maximum absorption is well explained by a change in the tilt angle between the phenyl and the yfide planes from 35-40degrees for the "red-absorbing" ylide to 55-60degrees for the other. However, the calculated enthalpies of formation of the various structures being nearly the same, these calculations do not allow us to assign one specific structure to one or the other of the observed species.PT: J; CR: *OXF MOL LTD, 1999, MOPAC AMI PM3 *SEM INC, 2003, AMPAC 7 2 BELIN C, 2001, J PHOTOCH PHOTOBIO A, V139, P111 BONNEAU R, 2003, J PHOTOCH PHOTOBIO A, V161, P43 GRAHAM WH, 1965, J AM CHEM SOC, V87, P4396 JACKSON JE, 1988, J AM CHEM SOC, V110, P5595 LIU MTH, 1994, INT J CHEM KINET, V26, P1179 MALINOWSKI ER, 1991, FACTOR ANAL CHEM MAZZUCATO U, 1991, CHEM REV, V91, P1679 NAITO I, 2001, J PHOTOCH PHOTOBIO A, V140, P33 OKI M, 1981, CHEM LETT, P649 OKI M, 1988, B CHEM SOC JPN, V61, P4303 TAKEDA N, 1997, CHEM-EUR J, V3, P62; NR: 13; TC: 3; J9: J PHYS CHEM A; PG: 7; GA: 774AMSource type: Electronic(1
Author Correction: Reply to: Postbiotics - when simplification fails to clarify
No full textIn the original Supplementary Table associated with this Correspondence, the terms “postbiotic” and “ISAPP” were misspelled in the column heading and footnote, respectively. These errors have now been corrected and the Supplementary information updated online; for transparency, the updated Supplementary Table is available in the online version of this Correction.</p
Author correction: The International Scientific Association of Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of postbiotics
No full textThe originally published article contained an error in Table 2 in which the study on L. gasseri CP2305 was wrongly attributed to reference 155; it should have cited reference 15: Nishida et al. Para- psychobiotic Lactobacillus gasseri CP2305 ameliorates stress- related symptoms and sleep quality. J. Appl. Microbiol. 123, 1561–1570 (2017). This error has now been corrected in the HTML and PDF versions of the article.</p
Reliable estimation of membrane curvature for cryo-electron tomography
No full textCurvature is a fundamental morphological descriptor of cellular membranes. Cryo-electron tomography (cryo-ET) is particularly well-suited to visualize and analyze membrane morphology in a close-to-native state and molecular resolution. However, current curvature estimation methods cannot be applied directly to membrane segmentations in cryo-ET, as these methods cannot cope with some of the artifacts introduced during image acquisition and membrane segmentation, such as quantization noise and open borders. Here, we developed and implemented a Python package for membrane curvature estimation from tomogram segmentations, which we named PyCurv. From a membrane segmentation, a signed surface (triangle mesh) is first extracted. The triangle mesh is then represented by a graph, which facilitates finding neighboring triangles and the calculation of geodesic distances necessary for local curvature estimation. PyCurv estimates curvature based on tensor voting. Beside curvatures, this algorithm also provides robust estimations of surface normals and principal directions. We tested PyCurv and three well-established methods on benchmark surfaces and biological data. This revealed the superior performance of PyCurv not only for cryo-ET, but also for data generated by other techniques such as light microscopy and magnetic resonance imaging. Altogether, PyCurv is a versatile open-source software to reliably estimate curvature of membranes and other surfaces in a wide variety of applications. Author summary Membrane curvature plays a central role in many cellular processes like cell division, organelle shaping and membrane contact sites. While cryo-electron tomography (cryo-ET) allows the visualization of cellular membranes in 3D at molecular resolution and close-to-native conditions, there is a lack of computational methods to quantify membrane curvature from cryo-ET data. Therefore, we developed a computational procedure for membrane curvature estimation from tomogram segmentations and implemented it in a software package called PyCurv. PyCurv converts a membrane segmentation, i.e. a set of voxels, into a surface, i.e. a mesh of triangles. PyCurv uses the local geometrical information to reliably estimate the local surface orientation, the principal (maximum and minimum) curvatures and their directions. PyCurv outperforms well-established curvature estimation methods, and it can also be applied to data generated by other imaging techniques
Alteraciones en la conectividad funcional de la “Default mode Network” en pacientes con psicosis: estudio de neuroimagen funcional en estado de reposo
No full textEn los últimos años, el descubrimiento de la existencia de redes neuronales que muestran coherencia en cuanto a su actividad espontánea durante el reposo, fenómeno conocido con el nombre de conectividad funcional (CF), ha proporcionado un medio fructífero para abordar las bases neurobiológicas de enfermedades psiquiátricas como la esquizofrenia. Uno de los muchos sistemas cerebrales que muestran patrones de actividad sincronizada es la “Default mode Network” (DN), red formada por una serie de regiones que disminuyen su actividad simultáneamente durante la realización de tareas cognitivas y que se activan durante periodos libres de tarea. Numerosos estudios han observado alteraciones en esta red en pacientes con esquizofrenia, sin embargo, existen una serie de factores limitantes para la interpretación y generalización de estos resultados: la mayoría de estos trabajos se han realizado con pacientes crónicos, sin fenotipos definidos y en diferentes estadios de la enfermedad. Por ello, en un intento de elucidar parámetros biológicos que definan fenotipos consistentes, los objetivos de estas tesis son, por un lado, estudiar la CF de la DN en las primeras fases de la enfermedad psicótica, y por otro lado, estudiar la CF de la DN en dos grupos de pacientes con esquizofrenia clínicamente diferenciados (uno con alucinaciones auditivas (AA) persistentes y otro sin historia de AA). Para ello, en el primero de los trabajos, se realizan adquisiciones de resonancia magnética funcional en estado de reposo (R-fMRI) en una muestra de 19 pacientes con un primer episodio de psicosis y 19 controles sanos. Posteriormente, se examina la CF de 11 semillas previamente seleccionadas pertenecientes a los dos subsistemas que conforman la DN (córtex dorsomedial prefrontal y lóbulo temporal medial), según trabajos previos de Andrews- Hanna. En el segundo trabajo se realizan adquisiciones de R-fMRI en una muestra de 19 pacientes con esquizofrenia y AA persistentes, 14 pacientes con esquizofrenia sin historia de AA y 20 controles sanos. Siguiendo la misma metodología que en el estudio anterior, se examina la CF de los dos subsistemas que conforman la DN. Los resultados muestran que la CF de la DN estaría ya alterada desde el inicio de la enfermedad psicótica. Además, en el caso de los pacientes con un primer episodio de psicosis, éstas alteraciones parecen limitarse al subsitema del córtex dorsomedial prefrontal. Los pacientes con esquizofrenia en cambio, aunque muestran alteraciones en ambos subsistemas de la DN, éstas són mucho mayores en el caso de los pacientes alucinadores, llegando a afectar a todas y cada una de las semillas examinadas. Además, los resultados muestran un patrón de alteraciones en la CF entre regiones pertenecientes a ambos subsystemas de la DN y regiones clave de la “Salience Network”, entre otras áreas, característico de los pacientes alucinadores.In recent years, the discovery of the existence of neural networks that show consistency in their spontaneous activity at rest, a phenomenon known as functional connectivity (FC), has provided a fruitful means of addressing the neurobiological basis of psychiatric diseases such as schizophrenia. One of several brain systems showing patterns of synchronized activity is the "Default mode Network" (DN), a network comprised of a number of regions that decrease their activity simultaneously when performing cognitive tasks and increase their activity during free task periods. Numerous studies have found abnormalities in this network in patients with schizophrenia. However, there are some limitations for the interpretation and generalization of these results; most of these studies were performed with chronic patients, without defined phenotypes and at different stages of the disease. Therefore, in an attempt to elucidate biological parameters that define consistent phenotypes, the objectives of this thesis are: firstly, to study the DN FC in the early stages of psychotic illness, and secondly, to study the DN FC in two clinically differentiated groups of patients with schizophrenia (one with persistent auditory hallucinations (AH) and one without a history of AH). To do so, in the first study, resting state functional magnetic resonance imaging acquisitions (R-fMRI) were performed on a sample of 19 patients with a first episode of psychosis and 19 healthy controls. Subsequently, taking advantage of the fractionation of the DN into two distinct subsystems (dorsomedial prefrontal cortex subsystem, and medial temporal lobe subsystem) and a validated set of 11 seed regions-of-interest (Andrews – Hanna), we examined the FC in all eleven of them. In the second study, R-fMRI acquisitions were performed on a sample of 19 patients with schizophrenia and persistent AH, 14 schizophrenia patients without a history of AH and 20 healthy controls. Following the same methodology as in the previous study, we examined the FC of the 11 ROI comprised in the DN. The results show that the DN FC is altered from the begining of psychotic illness. Furthermore, in the case of patients with a first episode of psychosis, these abnormalities appear to be limited to the dorsomedial prefrontal cortex subsystem. In the second study, both groups of patients exhibited alterations in both dMPFC and MTL subsystems of the DN. However, these alterations were greater in patients with persistent AH. In particular, these patients exhibited cross-network abnormalities between the DN and the salience processing system
Two-stages optimised design of the collector field of solar power tower plants
No full textAbstractIn solar power tower (SPT) systems, selecting the optimum location of thousands of heliostats and the most profitable tower height and receiver size remains a challenge. Given the complexity of the problem, breaking the optimisation process down into two consecutive steps is suggested here; first, a primary, or energy, optimisation, which is practically independent of the cost models, and then a main, or economic, optimisation. The primary optimisation seeks a heliostat layout supplying the maximum annual incident energy for all the explored combinations of receiver sizes and tower heights. The annual electric output is then calculated as the combination of the incident energy and the simplified (annual averaged) receiver thermal losses and power efficiencies. Finally, the figure of merit of the main optimisation is the levelised cost of electric energy (LCOE) where the capital cost models used for the LCOE calculation are reported by the System Advisor Model (SAM)-NREL and Sandia. This structured optimisation, splitting energy procedures from economic ones, enables the organisation of a rather complex process, and it is not limited to any particular power tower code. Moreover, as the heliostat field layout is already fully optimised before the economic optimisation, the profiles of the LCOE versus the receiver radius for the tower heights explored here are sharp enough to establish optima easily. As an example of the new procedure, we present a full thermo-economic optimisation for the design of the collector field of an actual SPT system (Gemasolar, 20MWe, radially staggered surrounding field with 2650 heliostats, 15h of storage). The optimum design found for Gemasolar is reasonably consistent with the scarce open data. Finally, optimum designs are strongly dependent on the receiver cost, the electricity tariff and the assumed maximum receiver surface temperature
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