Improving the Quality of the Input in the Term Structure Consistent Models

In finance, getting an accurate estimation of the term structure of interest rates is essential because this information is often used as input by other pricing financial models. In this paper, we point out the importance of selecting a suitable estimation of the term structure of interest rates. To show this fact, we use the Spanish Bond Market to estimate the initial interest rate and forward curves for one day, by using both McCulloch (1975) cubic polynomial splines, and Legendre's polynomials (Morini, 1998). We use these curves as input for pricing pure discount bonds with the Ho and Lee (1986) and Hull and White (1990) models. Then, we find the important result that using an inadequate interest rate curve affects dramatically the behaviour of the dynamic term structure models and, consequently, the estimation of the asset pricing modelsTerm structure of interest rates, dynamic consistent models

Matemàtiques i música. El taller pitagòric

Aquest treball de fi de màster està dedicat a la didàctica de les Matemàtiques des d’una vessant musical. Es tracta, doncs, d’un treball de recerca que té com a objectiu trobar el sentit matemàtic de la música, a través de l’estudi d’alguns dels grans descobriments que s’han dut a terme al llarg de la història. El punt de partida d’aquest treball és l’escola pitagòrica, pionera en estudiar de manera conjunta les dues disciplines i establir la relació entre proporcionalitat i harmonia, continuant per la seva evolució i els intents de ressolució dels problemes que se’n van derivar, com la comma pitagòrica. La recerca històrica arriba principalment fins el Barroc, moment culminant del procés d’evolució dels principis pitagòrics, gràcies a l’aplicació de les matemàtiques en aquesta disciplina per part de teòrics, matemàtics i filòsofs, entre d’altres. Aquest fet, juntament amb la nova manera de concebre la Música, més enfocada a la pràctica i a la facilitat d’interpretació, va permetre passar de l’escala pitagòrica a l’escala temperada, a la què estem habituats avui en dia. Però no només a través de la història podem establir vincles entre aquestes dues disciplines, si analitzem qualsevol partitura musical, descobrirem la presència de les matemàtiques no tan sols en la seva notació, sinó també en la seva estructura interna, la seva harmonia i la seva composició. L’aplicació d’aquest mètode d’ensenyament interdisciplinar ens pot ser de gran utilitat per a conseguir que els alumnes tinguin un visió més global del què estan aprenent, prenguin consciència de la gran quantitat d’aplicacions, fins i tot en disciplines més artístiques i millorin la seva predisposició a l’aprenentatge

Peroxide-Induced Synthesis of Maleic Anhydride-Grafted Poly(butylene succinate) and Its Compatibilizing Effect on Poly(butylene succinate)/Pistachio Shell Flour Composites

[EN] Framing the Circular Bioeconomy, the use of reactive compatibilizers was applied in order to increase the interfacial adhesion and, hence, the physical properties and applications of green composites based on biopolymers and food waste derived lignocellulosic fillers. In this study, poly(butylene succinate) grafted with maleic anhydride (PBS-g-MAH) was successfully synthetized by a reactive melt-mixing process using poly(butylene succinate) (PBS) and maleic anhydride (MAH) that was induced with dicumyl peroxide (DCP) as a radical initiator and based on the formation of macroradicals derived from the hydrogen abstraction of the biopolymer backbone. Then, PBS-g-MAH was used as reactive compatibilizer for PBS filled with different contents of pistachio shell flour (PSF) during melt extrusion. As confirmed by Fourier transform infrared (FTIR), PBS-g-MAH acted as a bridge between the two composite phases since it was readily soluble in PBS and could successfully form new esters by reaction of its multiple MAH groups with the hydroxyl (-OH) groups present in cellulose or lignin of PSF and the end ones in PBS. The resultant compatibilized green composites were, thereafter, shaped by injection molding into 4-mm thick pieces with a wood-like color. Results showed significant increases in the mechanical and thermomechanical rigidity and hardness, meanwhile variations on the thermal stability were negligible. The enhancement observed was related to the good dispersion and the improved filler-matrix interfacial interactions achieved by PBS-g-MAH and also to the PSF nucleating effect that increased the PBS's crystallinity. Furthermore, water uptake of the pieces progressively increased as a function of the filler content, whereas the disintegration in controlled compost soil was limited due to their large thickness.This research was funded by the Ministry of Science and Innovation (MICI) project number MAT2017-84909-C2-2-R.Rojas-Lema, SP.; Arévalo, J.; Gómez-Caturla, J.; Garcia-Garcia, D.; Torres-Giner, S. (2021). Peroxide-Induced Synthesis of Maleic Anhydride-Grafted Poly(butylene succinate) and Its Compatibilizing Effect on Poly(butylene succinate)/Pistachio Shell Flour Composites. Molecules. 26(19):1-28. https://doi.org/10.3390/molecules26195927S128261

Tailoring the Properties of Thermo-Compressed Polylactide Films for Food Packaging Applications by Individual and Combined Additions of Lactic Acid Oligomer and Halloysite Nanotubes

[EN] In this work, films of polylactide (PLA) prepared by extrusion and thermo-compression were plasticized with oligomer of lactic acid (OLA) at contents of 5, 10, and 20 wt%. The PLA sample containing 20 wt% of OLA was also reinforced with 3, 6, and 9 parts per hundred resin (phr) of halloysite nanotubes (HNTs) to increase the mechanical strength and thermal stability of the films. Prior to melt mixing, ultrasound-assisted dispersion of the nanoclays in OLA was carried out at 100 ºC to promote the HNTs dispersion in PLA and the resultant films were characterized with the aim to ascertain their potential in food packaging. It was observed that either the individual addition of OLA or combined with 3 phr of HNTs did not significantly affect the optical properties of the PLA films, whereas higher nanoclay contents reduced lightness and induced certain green and blue tonalities. The addition of 20 wt% of OLA increased ductility of the PLA film by nearly 75% and also decreased the glass transition temperature (Tg) by over 18 ºC. The incorporation of 3 phr of HNTs into the OLA-containing PLA films delayed thermal degradation by 7 ºC and additionally reduced the permeabilities to water and limonene vapors by approximately 8% and 47%, respectively. Interestingly, the highest barrier performance was attained for the unfilled PLA film plasticized with 10 wt% of OLA, which was attributed to a crystallinity increase and an effect of ¿antiplasticization¿. However, loadings of 6 and 9 phr of HNTs resulted in the formation of small aggregates that impaired the performance of the blend films. The here-attained results demonstrates that the properties of ternary systems of PLA/OLA/HNTs can be tuned when the plasticizer and nanofiller contents are carefully chosen and the resultant nanocomposite films can be proposed as a bio-sourced alternative for compostable packaging applications.This research work was funded by the Spanish Ministry of Science and Innovation (MICI) project numbers RTI2018-097249-B-C21 and MAT2017-84909-C2-2-R. S.R.-L is a recipient of a Santiago Grisolia grant from Generalitat Valenciana (GVA) (GRISOLIAP/2019/132). L.Q.-C. wants to thank GVA for his FPI grant (ACIF/2016/182) and the Spanish Ministry of Education, Culture, and Sports (MECD) for his FPU grant (FPU15/03812), while D.G.-G. also acknowledges GVA for his postdoctoral contract (APOSTD/2019/201). B.M.-R. and S.T.-G. acknowledge MICIU for her FPI grant (BES-2016-077972) and his Juan de la Cierva¿Incorporación contract (IJCI-2016-29675), respectively.Rojas-Lema, S.; Quiles-Carrillo, L.; Garcia-Garcia, D.; Melendez-Rodriguez, B.; Balart, R.; Torres-Giner, S. (2020). Tailoring the Properties of Thermo-Compressed Polylactide Films for Food Packaging Applications by Individual and Combined Additions of Lactic Acid Oligomer and Halloysite Nanotubes. Molecules. 25(8). https://doi.org/10.3390/molecules2508197625

Development and Characterization of Weft-Knitted Fabrics of Naturally Occurring Polymer Fibers for Sustainable and Functional Textiles

[EN] This study focuses on the potential uses in textiles of fibers of soy protein (SP) and chitin, which are naturally occurring polymers that can be obtained from agricultural and food processing by-products and wastes. The as-received natural fibers were first subjected to a three-step manufacturing process to develop yarns that were, thereafter, converted into fabrics by weft knitting. Different characterizations in terms of physical properties and comfort parameters were carried out on the natural fibers and compared to waste derived fibers of coir and also conventional cotton and cotton-based fibers, which are widely used in the textile industry. The evaluation of the geometry and mechanical properties revealed that both SP and chitin fibers showed similar fineness and tenacity values than cotton, whereas coir did not achieve the expected properties to develop fabrics. In relation to the moisture content, it was found that the SP fibers outperformed the other natural fibers, which could successfully avoid variations in the mechanical performance of their fabrics as well as impair the growth of microorganisms. In addition, the antimicrobial activity of the natural fibers was assessed against different bacteria and fungi that are typically found on the skin. The obtained results indicated that the fibers of chitin and also SP, being the latter functionalized with biocides during the fiber-formation process, showed a high antimicrobial activity. In particular, reductions of up to 100% and 60% were attained for the bacteria and fungi strains, respectively. Finally, textile comfort was evaluated on the weft-knitted fabrics of the chitin and SP fibers by means of thermal and tactile tests. The comfort analysis indicated that the thermal resistance of both fabrics was similar to that of cotton, whereas their air permeability was higher, particularly for chitin due to its higher fineness, which makes these natural fibers very promising for summer clothes. Both the SP and chitin fabrics also presented relatively similar values of fullness and softness than the pure cotton fabric in terms of body feeling and richness. However, the cotton/polyester fabric was the only one that achieved a good range for uses in winter-autumn cloths. Therefore, the results of this work demonstrate that non-conventional chitin and SP fibers can be considered as potential candidates to replace cotton fibers in fabrics for the textile industry due to their high comfort and improved sustainability. Furthermore, these natural fibers can also serve to develop novel functional textiles with antimicrobial properties.This research work was funded by the Spanish Ministry of Science and Innovation (MICI) project number MAT2017-84909-C2-2-R.Ferrándiz, M.; Fages, E.; Rojas-Lema, SP.; Ivorra-Martinez, J.; Gomez-Caturla, J.; Torres-Giner, S. (2021). Development and Characterization of Weft-Knitted Fabrics of Naturally Occurring Polymer Fibers for Sustainable and Functional Textiles. Polymers. 13(4):1-17. https://doi.org/10.3390/polym13040665S11713

On the Use of Phenolic Compounds Present in Citrus Fruits and Grapes as Natural Antioxidants for Thermo-Compressed Bio-Based High-Density Polyethylene Films

[EN] This study originally explores the use of naringin (NAR), gallic acid (GA), caffeic acid (CA), and quercetin (QUER) as natural antioxidants for bio-based high-density polyethylene (bio-HDPE). These phenolic compounds are present in various citrus fruits and grapes and can remain in their leaves, peels, pulp, and seeds as by-products or wastes after juice processing. Each natural additive was first melt-mixed at 0.8 parts per hundred resin (phr) of bio-HDPE by extrusion and the resultant pellets were shaped into films by thermo-compression. Although all the phenolic compounds colored the bio-HDPE films, their contact transparency was still preserved. The chemical analyses confirmed the successful inclusion of the phenolic compounds in bio-HDPE, though their interaction with the green polyolefin matrix was low. The mechanical performance of the bio-HDPE films was nearly unaffected by the natural compounds, presenting in all cases a ductile behavior. Interestingly, the phenolic compounds successfully increased the thermo-oxidative stability of bio-HDPE, yielding GA and QUER the highest performance. In particular, using these phenolic compounds, the onset oxidation temperature (OOT) value was improved by 43 and 41.5 ºC, respectively. Similarly, the oxidation induction time (OIT) value, determined in isothermal conditions at 210 ºC, increased from 4.5 min to approximately 109 and 138 min. Furthermore, the onset degradation temperature in air of bio-HDPE, measured for the 5% of mass loss (T5%), was improved by up to 21 ºC after the addition of NAR. Moreover, the GA- and CA-containing bio-HDPE films showed a high antioxidant activity in alcoholic solution due to their favored release capacity, which opens up novel opportunities in active food packaging. The improved antioxidant performance of these phenolic compounds was ascribed to the multiple presence of hydroxyl groups and aromatic heterocyclic rings that provide these molecules with the features to permit the delocalization and the scavenging of free radicals. Therefore, the here-tested phenolic compounds, in particular QUER, can represent a sustainable and cost-effective alternative of synthetic antioxidants in polymer and biopolymer formulations, for which safety and environmental issues have been raised over timeThis research work was funded by the Spanish Ministry of Science and Innovation (MICI) project number MAT2017-84909-C2-2-R.Rojas-Lema, SP.; Torres-Giner, S.; Quiles-Carrillo, L.; Gómez-Caturla, J.; Garcia-Garcia, D.; Balart, R. (2021). On the Use of Phenolic Compounds Present in Citrus Fruits and Grapes as Natural Antioxidants for Thermo-Compressed Bio-Based High-Density Polyethylene Films. Antioxidants. 10(1):1-23. https://doi.org/10.3390/antiox10010014S12310

Evaluation of Different Compatibilization Strategies to Improve the Performance of Injection-Molded Green Composite Pieces Made of Polylactide Reinforced with Short Flaxseed Fibers

[EN] Green composites made of polylactide (PLA) and short flaxseed fibers (FFs) at 20 wt % were successfully compounded by twin-screw extrusion (TSE) and subsequently shaped into pieces by injection molding. The linen waste derived FFs were subjected to an alkalization pretreatment to remove impurities, improve the fiber surface quality, and make the fibers more hydrophobic. The alkali-pretreated FFs successfully reinforced PLA, leading to green composite pieces with higher mechanical strength. However, the pieces also showed lower ductility and toughness and the lignocellulosic fibers easily detached during fracture due to the absence or low interfacial adhesion with the biopolyester matrix. Therefore, four different compatibilization strategies were carried out to enhance the fiber-matrix interfacial adhesion. These routes consisted on the silanization of the alkalized FFs with a glycidyl silane, namely (3-glycidyloxypropyl) trimethoxysilane (GPTMS), and the reactive extrusion (REX) with three compatibilizers, namely a multi-functional epoxy-based styrene-acrylic oligomer (ESAO), a random copolymer of poly(styrene-co-glycidyl methacrylate) (PS-co-GMA), and maleinized linseed oil (MLO). The results showed that all the here-tested compatibilizers improved mechanical strength, ductility, and toughness as well as the thermal stability and thermomechanical properties of the green composite pieces. The highest interfacial adhesion was observed in the green composite pieces containing the silanized fibers. Interestingly, PS-co-GMA and, more intensely, ESAO yielded the pieces with the highest mechanical performance due to the higher reactivity of these additives with both composite components and their chain-extension action, whereas MLO led to the most ductile pieces due to its secondary role as plasticizer for PLA.This research work was funded by the Spanish Ministry of Science and Innovation (MICI) project numbers RTI2018-097249-B-C21 and MAT2017-84909-C2-2-R. D.L. and J.I.-M. thanks UPV for the grant received through the PAID-01-18 and PAID-01-19 (SP2019001) programs, respectively. S.T.-G. is recipient of a Juan de la Cierva contract (IJCI-2016-29675) from MICIU while S.R.J. is funded through the Santiago Gisolía contract (GRISOLIAP/2019/132) from Generalitat Valenciana (GVA). The microscopy services of UPV are also acknowledged for their help in collecting and analyzing the FESEM images.Agüero, Á.; Garcia-Sanoguera, D.; Lascano-Aimacaña, DS.; Rojas-Lema, SP.; Ivorra-Martínez, J.; Fenollar, O.; Torres Giner, S. (2020). Evaluation of Different Compatibilization Strategies to Improve the Performance of Injection-Molded Green Composite Pieces Made of Polylactide Reinforced with Short Flaxseed Fibers. Polymers. 12(4):1-22. https://doi.org/10.3390/polym12040821S12212

Development of Injection-Molded Polylactide Pieces with High Toughness by the Addition of Lactic Acid Oligomer and Characterization of Their Shape Memory Behavior

[EN] This work reports the effect of the addition of an oligomer of lactic acid (OLA), in the 5-20 wt% range, on the processing and properties of polylactide (PLA) pieces prepared by injection molding. The obtained results suggested that the here-tested OLA mainly performs as an impact modifier for PLA, showing a percentage increase in the impact strength of approximately 171% for the injection-molded pieces containing 15 wt% OLA. A slight plasticization was observed by the decrease of the glass transition temperature (T-g) of PLA of up to 12.5 degrees C. The OLA addition also promoted a reduction of the cold crystallization temperature (T-cc) of more than 10 degrees C due to an increased motion of the biopolymer chains and the potential nucleating effect of the short oligomer chains. Moreover, the shape memory behavior of the PLA samples was characterized by flexural tests with different deformation angles, that is, 15 degrees, 30 degrees, 60 degrees, and 90 degrees. The obtained results confirmed the extraordinary effect of OLA on the shape memory recovery (R-r) of PLA, which increased linearly as the OLA loading increased. In particular, the OLA-containing PLA samples were able to successfully recover over 95% of their original shape for low deformation angles, while they still reached nearly 70% of recovery for the highest angles. Therefore, the present OLA can be successfully used as a novel additive to improve the toughness and shape memory behavior of compostable packaging articles based on PLA in the new frame of the Circular Economy.This research work was funded by the Spanish Ministry of Science, Innovation, and Universities (MICIU) project numbers RTI2018-097249-B-C21 and MAT2017-84909-C2-2-R. L.Q.-C. wants to thank Generalitat Valenciana (GVA) for his FPI grant (ACIF/2016/182) and the Spanish Ministry of Education, Culture, and Sports (MECD) for his FPU grant (FPU15/03812). D.L. thanks Universitat Politècnica de València (UPV) for the grant received through the PAID-01-18 program. S.T.-G. is recipient of a Juan de la Cierva contract (IJCI-2016-29675) from MICIU. S.R.-L. is recipient of a Santiago Grisolía contract (GRISOLIAP/2019/132) from GVA. J.I.-M. wants to thank UPV for an FPI grant PAID-01-19 (SP2019001). Microscopy services of UPV are acknowledged for their help in collecting and analyzing the microscopy images. Authors also thank Condensia Química S.A. for kindly supplying Glyoplast OLA 2.Lascano-Aimacaña, DS.; Moraga, G.; Ivorra-Martínez, J.; Rojas-Lema, SP.; Torres-Giner, S.; Balart, R.; Boronat, T.... (2019). Development of Injection-Molded Polylactide Pieces with High Toughness by the Addition of Lactic Acid Oligomer and Characterization of Their Shape Memory Behavior. Polymers. 11(12):1-19. https://doi.org/10.3390/polym11122099S1191112Dijkstra, P. J., Du, H., & Feijen, J. (2011). 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Preparation and Properties of Novel Thermoplastic Vulcanizate Based on Bio-Based Polyester/Polylactic Acid, and Its Application in 3D Printing. Polymers, 9(12), 694. doi:10.3390/polym9120694Kumar, S., Singh, R., Singh, T., & Batish, A. (2019). Investigations of polylactic acid reinforced composite feedstock filaments for multimaterial three-dimensional printing applications. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 233(17), 5953-5965. doi:10.1177/0954406219861665Matos, B. D. M., Rocha, V., da Silva, E. J., Moro, F. H., Bottene, A. C., Ribeiro, C. A., … Silva Barud, H. da. (2018). Evaluation of commercially available polylactic acid (PLA) filaments for 3D printing applications. Journal of Thermal Analysis and Calorimetry, 137(2), 555-562. doi:10.1007/s10973-018-7967-3Bayer, I. (2017). Thermomechanical Properties of Polylactic Acid-Graphene Composites: A State-of-the-Art Review for Biomedical Applications. 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CURRENT DISTRIBUTION, HABITAT USE, AND BREEDING RECORDS OF THE HOUSE SPARROW (PASSER DOMESTICUS) IN VENEZUELA

ABSTRACT ∙ The House Sparrow (Passer domesticus, Passeridae), native to Eurasia and northern Africa, was introduced to the Americas and Australia where it inhabits mainly urban environments. The objective of this study was to determine the distribution of the House Sparrow in Venezuela from our own observations and data reported in personal communications, published material, and eBird records. House Sparrows were recorded for first time in Venezuela in 1996 at the port of La Guaira. Since then, records have increased, and we found 133 records of the House Sparrow until July 2015, in the states of Falcón, Zulia, Vargas, Miranda, Carabobo, Anzoátegui, and Los Roques Archipelago. The states of Falcón and Vargas included the greatest number of records, and 2015 was the year with the most records. Most sightings occurred in urban areas of coastal Venezuela. House Sparrows were recorded within three protected areas: Refugio de Fauna Silvestre de Cuare (Falcón), Refugio de Fauna Silvestre y Reserva de Pesca Ciénaga de los Olivitos (Zulia), and Parque Nacional Archipiélago Los Roques. Two records for Caracas, one for Barquisimeto and another for Margarita Island, need confirmation. Breeding was confirmed in five states where the House Sparrow is currently present, and records indicated that the nesting season extends from February to November. Most nests (84%) were located in man‐made structures, but two breeding records included a nesting colony in cavities of an exotic palm (Phoenix sp.) in Falcón and a nest under a pile of dead coral fragments in Los Roques Archipelago. We found evidence of foraging on new food items from two coastal trees (Conocarpus erectus and Coccoloba uvifera). Formal research and long‐term surveys are required to assess the functional ecological role of this exotic species in the avian communities of Venezuela.  RESUMEN ∙ Distribución actual, uso de hábitat y registros reproductivos del Gorrión Común (Passer domesticus) en Venezuela El Gorrión Común (Passer domesticus, Passeridae), nativo de Eurasia y el norte de África, fue introducido en gran parte de América y Australia, donde ocupa principalmente hábitats urbanos. El objetivo de este trabajo consistió en determinar la distribución del Gorrión Común en Venezuela con base en nuestras observaciones y datos reportados en comunicaciones personales, material publicado y registros en eBird. Los Gorriones Comunes se registraron por primera vez en Venezuela en 1996 en el puerto de La Guaira. Desde entonces, el número de registros se ha incrementado y nosotros encontramos 133 registros de Gorrión Común fechados hasta el julio de 2015 para los estados Falcón, Zulia, Vargas, Miranda, Carabobo, Anzoátegui y el Archipiélago de Los Roques. Los estados con mayor número de registros fueron Falcón y Vargas, y el año con el mayor número de registros fue 2015. La mayor parte de los avistamientos se realizaron dentro de áreas urbanas en la costa de Venezuela. Se registraron gorriones en tres áreas protegidas: el Refugio de Fauna Silvestre de Cuare (Falcón), el Refugio de Fauna Silvestre y Reserva de Pesca Ciénaga de los Olivitos (Zulia) y el Parque Nacional Archipiélago Los Roques. Dos reportes de avistamientos para Caracas, uno para Barquisimeto y otro para la Isla de Margarita requieren confirmación. La reproducción fue confirmada en cinco de los estados donde el Gorrión Común está presente actualmente, y los registros indican que la época reproductiva se extiende de febrero a noviembre. La mayoría de los nidos (84%) se ubicaron en estructuras hechas por el hombre, pero dos registros reproductivos incluyen una colonia de anidación en cavidades de una palma exótica (Phoenix sp.) en Falcón, y un nido bajo una pila de fragmentos de coral muerto en el Archipiélago de Los Roques. Encontramos nueva evidencia de alimentación con ítems de dos árboles costeros (Conocarpus erectus y Coccoloba uvifera). Estudios formales y monitoreo a largo plazo son necesarios para evaluar el rol ecológico funcional de esta especie exótica en las comunidades de aves en Venezuela

Dose dependent gene expression is dynamically modulated by the history, physiology and age of yeast cells

[EN] Cells respond to external stimuli with transient gene expression changes in order to adapt to environmental alterations. However, the dose response profile of gene induction upon a given stress depends on many intrinsic and extrinsic factors. Here we show that the accurate quantification of dose dependent gene expression by live cell luciferase reporters reveals fundamental insights into stress signaling. We make the following discoveries applying this non-invasive reporter technology. (1) Signal transduction sensitivities can be compared and we apply this here to salt, oxidative and xenobiotic stress responsive transcription factors. (2) Stress signaling depends on where and how the damage is generated within the cell. Specifically we show that two ROS-generating agents, menadione and hydrogen peroxide, differ in their dependence on mitochondrial respiration. (3) Stress signaling is conditioned by the cells history. We demonstrate here that positive memory or an acquired resistance towards oxidative stress is induced dependent on the nature of the previous stress experience. (4) The metabolic state of the cell impinges on the sensitivity of stress signaling. This is shown here for the shift towards higher stress doses of the response profile for yeast cells moved from complex to synthetic medium. (5) The age of the cell conditions its transcriptional response capacity, which is demonstrated by the changes of the dose response to oxidative stress during both replicative and chronological aging. We conclude that capturing dose dependent gene expression in real time will be of invaluable help to understand stress signaling and its dynamic modulation.The authors thank Daniel E. Gottschling (Fred Hutchinson Cancer Research Center, Seattle, US) for the kind gift of MEP yeast strain UCC4925. This work was supported by the Ministerio de Economia y Competitividad (grant number BFU2016-75792-R).Pascual-Ahuir Giner, MD.; González-Cantó, E.; Juyoux, P.; Pable, J.; Poveda-Huertes, D.; Saiz-Balbastre Sandra; Squeo, S.... (2019). Dose dependent gene expression is dynamically modulated by the history, physiology and age of yeast cells. Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms. 1862(4):457-471. https://doi.org/10.1016/j.bbagrm.2019.02.009S4574711862