Design of bio-based materials derived from food industry wastes.

196 p.(eusk) 196 p.(eng.)Doktorego-tesi honetan biopolimeroen balioztatzearen zein proteinazko materialetan gaur egun erabiltzen diren prozesatze metodoak eta aplikazioak azaltzen dira. Elikagaien iraungitzea luzatzeko erabiltzen diren gelatinan oinarritutako materialak azpimarratu dira. Gelatinaren elektroharikatzea erronka handia denez, elektroharikatzeko gai diren soluzio aproposak aukeratzeko, arrain-gelatina/azido zitriko soluzioen neurketa erreologikoak aztertu dira. pH azidoak gelatinaren eta azidoaren arteko erreakzioa oztopatzen duela ikusi denez, pH basikoarekin lan egin da, disoluzio metodoaren bidez prestatutako gelatinazko filmetan saretzea sustatu eta propietateak hobetzeko. Gainera, film hauen ingurumen azterketa ere egin da. Ondoren, ontziratze aktibo edota adimendunetarako erabilgarriak diren materialak deskribatu dira. Horrela, disoluzio metodoaren bidez prestatutako filmen bakterioen aurkako aktibitatean eta propietate funtzionaletan azido zitrikoak eta kitosanoak duten efektu konbinatua aztertu da. Bakterioen aurkako eragileekin batera mota askotako konposatu antioxidatzaileak erabiltzen dira elikagaien ontziratzeetako materialetan. Testuinguru honetan, elikagaien prozesatzean sortutako aza more hondakinetatik erauzitako antioxidatzaile diren antozianinak aztertu dira. Gainera, antozianinak dituzten arrain gelatinazko filmak konpresio bidezko moldaketa erabiliz prestatu eta material hauen analisi sakon bat egin da. Liofilizazio bidez prestatutako tetrahidrokurkumina antioxidatzailea gehitua duten arrain-gelatinazko laginak, sendotze eragile gisa txibia lumetatik erauzitako kitina dutenak, ere etsaminatu dira

Design of bio-based materials derived from food industry wastes.

196 p.(eusk) 196 p.(eng.)Doktorego-tesi honetan biopolimeroen balioztatzearen zein proteinazko materialetan gaur egun erabiltzen diren prozesatze metodoak eta aplikazioak azaltzen dira. Elikagaien iraungitzea luzatzeko erabiltzen diren gelatinan oinarritutako materialak azpimarratu dira. Gelatinaren elektroharikatzea erronka handia denez, elektroharikatzeko gai diren soluzio aproposak aukeratzeko, arrain-gelatina/azido zitriko soluzioen neurketa erreologikoak aztertu dira. pH azidoak gelatinaren eta azidoaren arteko erreakzioa oztopatzen duela ikusi denez, pH basikoarekin lan egin da, disoluzio metodoaren bidez prestatutako gelatinazko filmetan saretzea sustatu eta propietateak hobetzeko. Gainera, film hauen ingurumen azterketa ere egin da. Ondoren, ontziratze aktibo edota adimendunetarako erabilgarriak diren materialak deskribatu dira. Horrela, disoluzio metodoaren bidez prestatutako filmen bakterioen aurkako aktibitatean eta propietate funtzionaletan azido zitrikoak eta kitosanoak duten efektu konbinatua aztertu da. Bakterioen aurkako eragileekin batera mota askotako konposatu antioxidatzaileak erabiltzen dira elikagaien ontziratzeetako materialetan. Testuinguru honetan, elikagaien prozesatzean sortutako aza more hondakinetatik erauzitako antioxidatzaile diren antozianinak aztertu dira. Gainera, antozianinak dituzten arrain gelatinazko filmak konpresio bidezko moldaketa erabiliz prestatu eta material hauen analisi sakon bat egin da. Liofilizazio bidez prestatutako tetrahidrokurkumina antioxidatzailea gehitua duten arrain-gelatinazko laginak, sendotze eragile gisa txibia lumetatik erauzitako kitina dutenak, ere etsaminatu dira

Nuevos hablantes de euskera: identidad y legitimidad

En els últims 40 anys el nombre de bascoparlants ha crescut molt a causa, sobretot, de l'augment dels nous parlants o, utilitzant la terminologia en basc, euskaldunberris, definits aquí com totes aquelles persones que han après aquesta llengua per un mitjà diferent de la transmissió familiar. Encara que el grup dels nous parlants de basc és estratègic per al desenvolupament futur de la llengua, fins a aquesta recerca no hi ha hagut cap estudi en profunditat sobre ells.Aquest article presenta alguns dels resultats relacionats amb la identitat lingüística dels nous parlants. S'hi exploren les autoadscripcions a les tres principals categories que les vehiculen —euskaldun zaharra (parlant nadiu), euskaldunberri (nou parlant) i euskaldun (parlant de basc)— i s'hi argumenta que aquestes categories indexen identitats que se situen en un continuum d'autenticitat que, al seu torn, es correlaciona amb l'autopercepció dels parlants com a legítims parlants de basc.The number of Basque speakers has grown considerably in the last 40 years, due largely to the rising number of new speakers, or euskaldunberris, defined here as those people who have learned the language through any means other than family transmission. Although new Basque speakers constitute a strategic group for the future development of the language, until now no detailed study of this collective had been attempted.In this article we present the results of research into the perceived linguistic identities of new Basque speakers, exploring the participants’ reasons for assigning themselves to one of three principal categories: euskaldun zaharra (native speaker), euskaldunberri (new speaker) and euskaldun (Basque speaker). It is argued that these categories reflect identities that can be situated in a continuum of authenticity that, in turn, correlates with the speakers’ self-perception as legitimate speakers of Basque.En los últimos 40 años el número de vascohablantes ha crecido mucho debido en gran parte al aumento de los nuevos hablantes o, utilizando la terminología en euskera, euskaldunberris, definidos aquí como todas aquellas personas que han aprendido esta lengua por un medio diferente a la transmisión familiar. Aunque el grupo de los nuevos hablantes de euskera es estratégico para el desarrollo futuro de la lengua, hasta esta investigación no ha habido ningún estudio en profundidad sobre ellos.Este artículo presenta algunos de los resultados relacionados con la identidad lingüística de los nuevos hablantes. Se exploran las autoadscripciones a las tres principales categorías que las vehiculan —euskaldun zaharra (hablante nativo), euskaldunberri (nuevo hablante) y euskaldun (hablante de euskera)— y se argumenta que estas categorías indexan identidades que se sitúan en un continuum de autenticidad que, a su vez, se correlaciona con la autopercepción de los hablantes como legítimos hablantes de euskera

Authenticity and linguistic variety among new speakers of Basque

This paper argues that the type of variety learned and used by Basque language learners is a key element in their self-perception as “true” or authentic speakers of Basque. Drawing on focus groups and individual interviews, we find that new speakers are for the most part strongly oriented towards the value of authenticity epitomized by local varieties. While new speakers report the utility of their mastery over the new standard Basque variety, they are not inclined to view this mastery as granting themselves greater authority or ownership over Basque. Rather they strongly valorize the informal and vernacular speech forms indexing colloquial speech and local dialect most identified with native speakers. The new speaker’s sociolinguistic context and motivations for learning Basque seem to be predictive of the strength of this orientation. The findings of this study point to the necessity of further study and documentation of local vernacular as well the urgency for language educators to find ways of incorporating the acquisition of local and dialectal features into language instruction.National Foreign Language Resource Cente

The Effect of Cross-Linking with Citric Acid on the Properties of Agar/Fish Gelatin Films

The aim of this work was to assess the effect of fish gelatin–citric acid nucleophilic substitution and agar–citric acid esterification reactions on the properties of agar/fish gelatin films. Since temperature is an important cross-linking parameter, films were treated at 90 °C and 105 °C and film properties were compared to those of non-cured films. It was observed that temperature favored the aforementioned reactions, which induced physical and morphological changes. In this regard, darker films with a rougher surface were obtained for the films with a higher cross-linking degree. While mechanical properties were slightly modified, the barrier properties were enhanced due to the reactions that occurred. Therefore, these agar/fish gelatin films cross-linked through two different reactions can be considered to be promising materials as active films for different purposes, such as active packaging or pharmaceutical applications.This research was funded by the Ministry of Science, Innovation, and Universities (RTI2018-097100-B-C22)

Combination of 3D printing and electrospinning to develop chitin/gelatin/PVA scaffolds

In this study, novel scaffolds based on natural polymers were developed by combining 3D printing (3DP) and electrospinning (ES) techniques. ES ink was prepared with gelatin and poly(vinyl alcohol) (PVA), while 3DP ink was prepared with gelatin and chitin. Different biopolymers were used to confer unique properties to each ink and obtain a multilayered scaffold suitable for tissue regeneration. First, gelatin is able to exhibit the characteristics needed for both inks since gelatin chains contain arginineglycine-aspartic (RGD) motifs, an important sequence in the promotion of cell adhesion, which gives gelatin an improved biological behavior in comparison to other polymers. Additionally, PVA was selected for ES ink to facilitate gelatin spinnability, and chitin was incorporated into 3DP ink as reinforcement to provide mechanical support and protection to the overall design. In this work, chitin was extracted from fruit fly pupae. The high extraction yield and purity of the chitin obtained from the fruit fly pupae confirmed that this pupa is an alternative source to produce chitin. Once the chitin was characterized, both inks were prepared and rheological analysis was carried out in order to confirm the shear thinning behavior required for additive manufacturing processes. The combination of 3DP and ES processes resulted in porous scaffolds, which were proven biocompatible, highlighting their potential for biomedical applications.This work was supported by the Basque Government through the research groups of the Basque university system (IT1658-22) and through Elkartek Program (KK- 2022/00019). Work at Biodonostia was supported by Project PI19/01621, funded by Instituto de Salud Carlos III (ISCIII) and co-funded by the European Union. J.U. thanks the University of the Basque Country (ESPDOC21/74).T.C. (PRE_2021_1_0254) and A.I. (PRE_2019_1_0031) thank the Basque Government for their fellowships

Electrospinning of Fish Gelatin Solution Containing Citric Acid: An Environmentally Friendly Approach to Prepare Crosslinked Gelatin Fibers

The majority of the crosslinking approaches employed to confer water resistance properties to electrospun gelatin mats are based on the use of potential cytotoxic agents, turning out to be not suitable for biomedical applications. Environmentally friendly chemical strategies based on the use of non-toxic agents are, therefore, strongly demanded. In the present work, the possibility to produce crosslinked electrospun fish gelatin mats by electrospinning an aqueous solution, containing citric acid as a crosslinking agent, is reported. The effect of pH on solution rheological properties, as well as on the electrospun mat morphology, chemistry, and crosslinking degree, is assessed. The increase of solution pH from 1.8 to 3.7 allows for obtaining fibers that maintain the fibrous morphology also in the mat. Subsequent thermal treatment of the electrospun mat (80 degrees C for 30 min) turns out to increase the crosslinking degree and morphological stability of the mat.This research was funded by the Spanish Ministry of Science, Innovation and Universities (RTI2018-097100-B-C22), the Basque Government (Department of Quality and Food Industry), the Provincial Council of Gipuzkoa (Department of Economic Development, the Rural Environment and Territorial Balance) and the Italian Ministry of University and Research (MIUR)

Arrain-hondakinak baloratzea, gazta ontziratzeko

Elikagaiak ontziratzeko filmak aztertzea garrantzitsua da, ikerketaren bidez gaur egun merkatuan dauden ontziratzeen propietateak hobetzea ahalbidetu baitaiteke. Kasu honetan, polimero berriztagarri eta biodegradagarri bat erabiliz, hainbat azido zitriko kantitatetako filmak egin dira. Haien propietateak aztertu dira, bai eta gazten ontziratzean duten jarrera. Arrain-gelatinazko film hauek film komertzialek eskaintzen ez dituzten zenbait propietate interesgarri erakutsi dituzte; esaterako, gaztak bere koipea gordetzea eta ez lehortzea ahalbidetzen dute

Sustainable lithium-ion battery separators based on cellulose and soy protein membranes

The food industry produces millions of tons of natural by-products. Through this study, we followed an environmentally friendly strategy using discards, such as soy protein isolate (SPI) from soya oil production and marine cellulose (Cell) from the agar industry, in order to achieve added-value applications. In particular, this work focuses on the development of membranes based on soy protein and cellulose, and their validation as battery separator membranes toward sustainable energy storage systems. SPI membranes with Cell show excellent compatibility with the electrolyte based on physical interactions. These physical interactions favor the swelling of the membranes, reaching swelling values of 1000% after three days in the liquid electrolyte. The membranes are thermally stable up to 180 °C. After being subjected to the liquid electrolyte, it is observed that the microstructure of the membranes change, but the porous structure is maintained, while the materials remain easy to handle. The ionic conductivity value, lithium transference number and battery performance in cathodic half-cells are ∼ 5.8 mS.cm−1, 0.77, and 112 mAh.g−1 at 1C-rate, respectively. Overall, considering environmental issues and circular economy, it is proven that it is possible to obtain more sustainable high-performance lithium-ion batteries based on waste materials.The authors thank the Fundação para a Ciência e Tecnologia (FCT) for financial support under the framework of Strategic Funding UIDB/04650/2020, UID/FIS/04650/2020, UID/EEA/04436/2020, and UID/QUI/00686/2020 and under projects MIT-EXPL/TDI/0033/2021, POCI-01-0247-FEDER-046985 and 2022.03931.PTDC funded by national funds through FCT and by the ERDF through the COMPETE2020—Programa Operacional Competitividade e Internacionalização (POCI). The authors also thank the FCT for financial support under Grant 2021.08158.BD (J.P.S.) and FCT investigator contracts CEECIND/00833/2017 (RG) and 2020.04028.CEECIND (C.M.C.). This study forms part of the Advanced Materials program and was supported by MCIN with funding from European Union NextGenerationEU (PRTR-C17.I1) and by The Basque Government under the IKUR program. The authors also thank the project BIDEKO, funded by MCIN/AEI, NextGenerationEU, PRTR. This work was also supported by the (IT1658-22) and Grant PID2021-124294OB-C22 funded by MCI/AEI10.13039/501100011033 and by “ERDF A way of making Europe”. J.U. thanks the University of the Basque Country for her fellowship (ESPDOC21/74)