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Almost 30 years ago pioneering work by the laboratories of Harald von Boehmer and Susumo Tonegawa provided the first indications that developing thymocytes could assemble a functional TCRβ chain-containing receptor complex, the pre-TCR, before TCRα expression. The discovery and study of the pre-TCR complex revealed paradigms of signaling pathways in control of cell survival and proliferation, and culminated in the recognition of the multifunctional nature of this receptor. As a receptor integrated in a dynamic developmental process, the pre-TCR must be viewed not only in the light of the biological outcomes it promotes, but also in context with those molecular processes that drive its expression in thymocytes. This review article focuses on transcription factors and target genes activated by the pre-TCR to drive its different outcomes. ; Work in CL-R and JA laboratory has been supported by the Ramón y Cajal and I3 Researchers Programs (CL-R), research grants from the Spanish Government (SAF2009-08066, SAF2012-36535 to CL-R; and BFU2008-01070, SAF2011-24268 to JA), Fundació la Marató TV3 (080730, 122530 to CL-R and JA), the Marie Curie International Reintegration Program of the European Union (MCIRG516308 to CL-R), the Spanish Ministry of Health (ISCIII-RETIC RD06/0009-FEDER), and Generalitat de Catalunya (2009SGR601, 2014SGR1153). CL-R is a recipient of the ICREA Acadèmia Award (Generalitat de Catalunya).

Trabajo presentado en el VII International Symposium on Marine Sciences (ISMS), celebrado del 1 al 3 de julio de 2020, en Barcelona (España) ; Very long-chain (>C24) polyunsaturated fatty acids (VLC-PUFA), although present in small amounts, play important roles for the correct development and functionality of neural tissues, especially during early development of vertebrates [1]. However, studies on VLC-PUFA in fish are scarce. Their biosynthesis, mediated by elongation of very long-chain fatty acid 4 (Elovl4) proteins, is substrate-dependent. So, shorter fatty acid precursors, i. e. long-chain (C20-24) polyunsaturated fatty acids (LC-PUFA), are required. These nutrients are mostly incorporated by the diet and their bioavailability can determine the capacity of Elovl4 for satisfying the physiological VLC-PUFA demands in marine fish [2]. Thus, nutritional regulation of Elovl4, as well as other elongase and desaturase genes involved in LC-PUFA biosynthesis (Elovl5, Fads2) has been proposed as a strategy to enhance endogenous production of LC-PUFA and VLC-PUFA in fish farming [2]. This study aimed at investigating the nutritional regulation of genes involved in the biosynthesis of VLC-PUFA (elovl4a, elovl4b) and LC-PUFA (fads2, elovl5) in early life-cycle stages (larvae and post-larvae) of Sparus aurata and Solea senegalensis fed diets adapted to each development stage, live prey for larvae and microdiets for post-larvae, with a variable content in VLC-PUFA precursors, i.e. LC-PUFA. The results denoted that fads2, elovl5, elovl4a and elovl4b genes can be regulated by dietary LC-PUFA content. It is important to highlight that elovl4a and elovl4b genes, strongly expressed in neural tissues of both fish species, were differently regulated according to the species-specific VLC-PUFA putative needs associated with each early life-stage and the LC-PUFA dietary availability. These results can help to elucidate the molecular mechanism controlling the VLC-PUFA biosynthesis and their species-specific requirements along of the marine fish development. Thus, this study opens the possibility to incorporate successfully alternative lipid sources, through an early nutritional programming that stimulates the VLC-PUFA biosynthesis during the first exogenous feeding stages. ; This research was funded by the projects AGL 2013-40986-R (Spanish Government, Ministry of Economy and Competitiveness), and PROMETEO II / 2014/085 (Generalitat Valenciana). Miguel Torres was supported by a PhD funding program from Diputación de Castellón. ; Peer reviewed

23 Páginas.-- 6 Tablas.-- 5 Figuras ; The table olive industry produces a high quantity of wastewater annually. These wastewaters are very problematic because of their characteristics of high organic matter, high phenolic content, high salinity and conductivity. The quantities in which they are produced are also a serious problem. The worldwide production of table olives reached 2,550,000 tons in the last five campaigns, with the European Union contributing to 32% of total production. The problem of these wastewaters is focused on the Mediterranean area where the highest quantity of table olives is produced and to a lesser extent on the United States and South America. Countries like Spain produce around 540,000 tons of these wastewaters. At present, there is no standard treatment for these wastewaters with acceptable results and which is applied in the industry. Currently, the most common treatment is the storage of these wastewaters in large evaporation ponds where, during the dry season, the wastewater disappears due to evaporation. This is not a solution as the evaporation ponds depend completely on the climatology and have a high number of associated problems, such as bad odors, insect proliferation and the contamination of underground aquifers. Different studies have been carried out on table olive wastewater treatment, but the reality is that at the industrial level, none has been successfully applied. New and promising treatments are needed. The current review analyzes the situation of table olive wastewater treatment and the promising technologies for the future. ; The authors wish to express their gratitude to the regional government of Andalucía, Junta de Andalucía, Consejería de Economía y Conocimiento (Project of Excellence RNM-1970) for providing financial support. Dr. Rincón wishes to thank the "Ramón y Cajal" Program (RYC-2011-08783 contract) from the Spanish Ministry of Economy and Competitiveness for providing financial support. They acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI). ; Peer reviewed

Interspecific hybrids among species in the Saccharomyces genus are frequently detected in anthropic habitats and can also be obtained easily in the laboratory. This occurs because the most important genetic barriers among Saccharomyces species are post‐zygotic. Depending on several factors, including the involved strains, the hybridization mechanism and stabilization conditions, hybrids that bear differential genomic constitutions, and hence phenotypic variability, can be obtained. In the present study, Saccharomyces cerevisiae × Saccharomyces uvarum hybrids were constructed using genetically and physiologically different S. uvarum parents at distinct temperatures (13 and 20°C). The effect of those variables on the main oenological features of the wines obtained with these hybrids was evaluated. Hybrids were successfully obtained in all cases. However, genetic stabilization based on successive fermentations in white wine at 13°C was significantly longer than that at 20°C. Our results demonstrated that, irrespective of the S. uvarum parent and temperature used for hybrid generation and stabilization, similar physicochemical and aromatic features were found in wines. The hybrids generated herein were characterized by low ethanol production, high glycerol synthesis and the capacity to grow at low temperature and to produce malic acid with particular aroma profiles. These features make these hybrids useful for the new winemaking industry within the climate change era frame. ; This work was supported by grants PICT 2011‐1738 and PICT 2015‐1198 from ANPCyT, PIP 2015‐555 from CONICET and PI04‐A128 from Universidad Nacional del Comahue (Argentina) to C.A.L., AGL2012‐39937‐C02‐01 and AGL2015‐67504‐C3‐1‐R from the Spanish Government and ERDF (European Regional Development Fund) and by grant PROMETEO (project PROMETEOII/2014/042) from Generalitat Valenciana to A.Q. ; Peer reviewed

Este artículo utiliza el Análisis Cualitativo Comparado (QCA) para estudiar procesos de transferencia de conocimiento difíciles de observar debido a la ausencia de fuentes de datos estandarizados. Estudia las relaciones entre universidad y empresa focalizando en las posibilidades de las empresas de contratar proyectos y servicios de I+D en un sistema local de innovación. El artículo realiza contribuciones de carácter metodológico y sustantivo. En primer lugar, las aproximaciones cualitativas de carácter micro y meso se acercan a la tradición de los estudios cuantitativos sobre la ciencia a través de un proceso que ilustra la construcción de dimensiones cuantificables y sus posibilidades de análisis. En segundo lugar, el análisis muestra los condicionantes que influyen en que las pequeñas y medianas empresas no intensivas en I+D utilicen conocimiento de la universidad. Las conclusiones resaltan las posibilidades de fertilización cruzada de esta metodología con otros enfoques en el estudio empírico de la ciencia y la innovación.

4 Tablas.-- 2 Figuras ; Spent livestock bedding is a valuable resource for the production of green energy (methane) in rural areas. Comparison and evaluation of batch anaerobic digestion and co-digestion of different mixtures of goat straw bedding (SGSB) and goat cheese whey were carried out. Biochemical methane potential (BMP) tests of the 100% SGSB, 95% SGSB-5% whey, 90% SGSB-10% whey, 85% SGSB-15% whey and 100% whey were found to be 423 ± 7, 354 ± 9, 371 ± 2, 293 ± 1, 274 ± 2 mL CH4 g−1 VS. Two different kinetic models were evaluated. The logistic model revealed a decrease in the maximum methane production rate (Rm) from 34.7 ± 1.5 to 14.1 ± 0.9 mL CH4 g−1 VS·d−1 when the percentage of whey in the mixture increased from 0 to 15% as a consequence of the increased ammonia released during the co-digestion of increased concentrations of whey. The lowest value for the maximum methane production predicted by the model (P) was found for 100% whey (274 ± 10 mL CH4 g−1 VS). A two-substrate model was applied to describe the evident existence of rapid and slowly degradable material. Regarding the hydrolysis kinetic constants predicted by this model, considerable increases in the rapid biodegradation stage (krapid) were observed when comparing to the values found for the slow (kslow) biodegradation stage in all the cases tested. The increases between both constants rose from 5 to 42% when the percentage of whey increased. ; The authors wish to thank to the regional government of Andalucía, Junta de Andalucía, Consejería de Economía y Conocimiento (Project of Excellence RNM-1970) for providing financial support. N.F. Puntano also wishes to thank the academic mobility and exchange program (PIMA). The PIMA program is a mobility initiative for undergraduate students promoted by the Ibero-American States Organization. The authors also wish especially to thank Manuel Vázquez (Sierra del Romero) for his contribution. ; Peer reviewed

16 Páginas.-- 7 Figuras.-- 2 Tablas ; This research was carried out with the aim to evaluate the anaerobic digestion (AD) of llama and dromedary dungs (both untreated and trampled) in batch mode at mesophilic temperature (35 °C). The biochemical methane potential (BMP) tests with an inoculum to substrate ratio of 2:1 (as volatile solids (VS)) were carried out. The methane yield from trampled llama dung (333.0 mL CH4 g−1 VSadded) was considerably higher than for raw llama, raw and trampled dromedary dungs (185.9, 228.4, 222.9 mL CH4 g−1 VSadded, respectively). Therefore, trampled llama dung was found to be the best substrate for methane production due to its high content of volatile solids as well as its high nitrogen content (2.1%) and more appropriate C/N ratio (23.6) for AD. The experimental data was found to be in accordance with both first-order kinetic and transference function mathematical models, when evaluating the experimental methane production against time. By applying the first-order kinetic model, the hydrolysis rate constants, kh, were found to be 19% and 11% higher for trampled dungs in comparison with the raw dung of dromedary and llama, respectively. In addition, the maximum methane production rate (Rm) derived from the transference function model for trampled llama dung (22.0 mL CH4 g−1 VS d−1) was 83.3%, 24.4% and 22.9% higher than those obtained for raw llama manure and for raw and trampled dromedary dungs, respectively. ; Funding for open access publishing: Universidad Pablo de Olavide/CBUA. This study was funded y the project FEDER UPO-1380782 financed by the regional government of Andalucía, Junta de Andalucía, Consejería de Trasformación Económica, Industria, Conocimiento y Universidades and the project PID2020-114975RB-100/AEI/10.13039/501100011033 financed by the Spanish Ministry of Science and Innovation. ; Peer reviewed

Introduction. The productivity of certain crops such as coffee (Coffea arabica L.), maize (Zea mays) and beans (Phaseolus vulgaris L.) is expected to decline in Central America because of climate change. This will impact regional economies and livelihoods of smallholder farmers relying on these crops for their food security and livelihoods. There is a need to understand how climate change is already impacting smallholder farmers in Guatemala in order to promote adaptation measures that will allow them to face these impacts. Objective. The objectives of this study were to characterize two Guatemalan small-scale agricultural systems, describe farmers' perceptions of climate change and impacts, and document their adaptation efforts. Materials and methods. Structured surveys were carried out in households growing coffee or basic grains in Acatenango and Chiquimula landscapes, two climate change vulnerable landscapes, between June and July 2014. The research was based on farmers' perceptions of changes in temperature and rainfall, the impacts related to these changes, and the adaptation actions implemented in response to perceived changes. Results. Results indicated that 95% of farmers perceived changes in climate, and 81% of them considered these changes to have negatively affected their production. Only 41% of farmers had implemented measures to adapt to these changes, mainly those farmers growing coffee. The implemented adaptation measures differed between landscapes , crops, and usefulness against perceived change with tree planting being the most common adaptation practice to buffer against temperature increases. Conclusion. In order to improve the adaptive response ofsmallholder farmers and to promote the use of practices that increase resilience, it is neecessaryto provide more technical, financial and political support to facilitate the adaptation of small farmers facing climate change. ; Introducción. Se espera que, a consecuencia del cambio climático, cultivos como el café (Coffea arabica L.), maíz (Zea mays) y frijol (Phaseolus vulgaris L.) sean menos productivos en América Central. Esto perjudicará la economía regional y los medios de vida de los pequeños productores, quienes dependen de estos cultivos para su seguridad alimentaria y bienestar. Es necesario entender cómo el cambio climático está afectando a los pequeños productores agrícolas en Guatemala para promover medidas que permitan enfrentar estos cambios. Objetivo. El objetivo de este trabajo fue caracterizar dos sistemas agrícolas de pequeña escala guatemaltecos, documentar cómo los pequeños productores perciben los impactos del cambio climático e identificar los esfuerzos de adaptación realizados. Materiales y métodos. Se realizaron encuestas estructuradas en hogares productores de café o granos básicos en los paisajes de Acatenango y Chiquimula, vulnerables al cambio climático, entre junio y julio de 2014. La investigación recogió las percepciones de los productores sobre cambios en temperatura y lluvia, los impactos reportados como consecuencia de dichos cambios y las acciones implementadas en las fincas a modo de respuesta. Resultados. Los resultados indicaron que el 95 % de los encuestados percibió cambios en el clima en la última década y el 81 % consideró que estos cambios afectaron negativamente su producción. El 41 % de los productores implementaron prácticas para adaptarse a los cambios percibidos, en mayor medida aquellos que producen café. Las prácticas de adaptación implementadas en las fincas difirieron entre paisajes, cultivos y cambio percibido, siendo la más utilizada la siembra de árboles para amortiguar los efectos del incremento de temperatura. Conclusión. Para lograr una mayor respuesta adaptativa de los pequeños productores y para promover el uso de prácticas que incrementen su resiliencia, es necesario incrementar el apoyo técnico, financiero y político orientado a facilitar la adaptación de los pequeños productores ante el cambio climático.