Repositori Obert UdL
The institutional repository collects, manages, disseminates and preserves publications in open access derived from the academic and research activity of the University of Lleida.

Recent Submissions
Item
Open Access
Teixits no teixits d'alt valor afegit per als sectors higiènic i quirúrgic
(2025-02) Ortiz Almirall, Laura
Aquest projecte se centra en el desenvolupament de dos nous productes de teixit no teixit (TNT) fabricats pel mètode de consolidació química i dissenyats específicament per a aplicacions en els sectors higiènic i quirúrgic.
En l'àmbit higiènic, l'objectiu principal ha estat dissenyar un TNT per utilitzar-lo en bolquers d'un sol ús, amb propietats tècniques avançades que millorin el rendiment i el confort del producte final.
Al sector quirúrgic, el projecte busca desenvolupar un TNT que formarà part d'un material laminat usat a les sales d'operació. Aquest material ha de complir requisits específics d'alta absorció i no ha de deixar anar cap mena de traça en fregar-se.
El desenvolupament d'aquests productes representa un avenç significatiu en el disseny de materials no teixits, combinant innovació tècnica amb aplicacions pràctiques per satisfer les exigències dels sectors tan especialitzats com són l'higiènic i el quirúrgic.
S’han obtingut resultats satisfactoris en els dos projectes de teixit no teixit. En el cas del projecte per a bolquers d’un sol ús, la millor combinació de fibres ha resultat ser 60% fibra PES 2 i 40% fibra acrílica 1, ja que ofereix els millors resultats en formació del vel, una alta resistència, absència de forats i una bona distribució de fluids. No s’han fet proves addicionals de resines, ja que s’ha optat per una resina estàndard basada en experiències
prèvies.
Pel que fa al projecte per a sales quirúrgiques, s’han desenvolupat tres tipus de materials: 100% fibra viscosa 3, 90% fibra viscosa 3 amb 10% fibra polièster, i 50% fibra viscosa 3 amb 50% fibra acrílica. La consolidació s’ha fet amb Resina 3 (250 g/L) i altres additius, incloent-hi Catalitzador 3 per millorar el test del linting, que mesura les partícules despreses del material en presència d’etanol. El material final és de color blau i presenta característiques similars a les sol·licitades pel client.
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Open Access
Spatially variable pesticide application in olive groves: Evaluation of potential pesticide-savings through stochastic spatial simulation algorithms
(2021-03-02) A. Rodríguez-Lizana; M.J. Pereira; M. Castro Ribeiro; A. Soares; L. Azevedo; A. Miranda-Fuentes; J. Llorens
Site-specific management using spatial crown volume characterization can greatly reduce the amount of pesticides applied in agricultural treatments performed with air-assisted sprayers, while helping farmers achieve the European legislation on safe use of pesticides. Nevertheless, variable rate treatments in olive groves have received little attention. Thus, field research was conducted in a 20.6-ha traditional olive grove. Two attributes of the trees - tree crown volume (V) and tree projected area - were determined, using 67 samples for V and all trees of the field (1433) for tree projected area. Spatial continuity of both attributes was modelled with exponential variograms. To gain a measure of local uncertainty, stochastic simulation algorithms were applied. One hundred simulated images were obtained for tree projected area using direct sequential simulation. Tree projected area simulations were used to improve spatial prediction of V, more difficult and more expensive to obtain, taking advantage of the high linear correlation between both variables (rxy = 0.72, p < 0.001). Thus, direct sequential cosimulation was employed to predict the spatial distribution of V, obtaining 100 geostatistical realizations of V. In order to estimate the potential reduction of pesticide use in the farm with variable rate treatments, two cut-off values of V were considered (50 and 100 m3crown volume). Local uncertainty, understood as the probability of each tree belonging to a given crown volume interval was determined. Probability maps were further transformed to morphological maps and finally to variable prescription maps. Two scenarios with 2 and 3 management zones (MZs) were obtained. In comparison with a conventional phytosanitary application, the variable rate treatments could reduce the pesticide amounts by 21.3% with 2 MZs, and by 38% with 3 MZs. The joint use of V and tree projected area in stochastic sequential simulation algorithms has shown to be useful to determine MZs in olive groves.
Item
Open Access
Spatially variable pesticide application in olive groves: Evaluation of potential pesticide-savings through stochastic spatial simulation algorithms
(2021-03-02) A. Rodríguez-Lizana; M.J. Pereira; M. Castro Ribeiro; A. Soares; L. Azevedo; A. Miranda-Fuentes; J. Llorens
Site-specific management using spatial crown volume characterization can greatly reduce the amount of pesticides applied in agricultural treatments performed with air-assisted sprayers, while helping farmers achieve the European legislation on safe use of pesticides. Nevertheless, variable rate treatments in olive groves have received little attention. Thus, field research was conducted in a 20.6-ha traditional olive grove. Two attributes of the trees - tree crown volume (V) and tree projected area - were determined, using 67 samples for V and all trees of the field (1433) for tree projected area. Spatial continuity of both attributes was modelled with exponential variograms. To gain a measure of local uncertainty, stochastic simulation algorithms were applied. One hundred simulated images were obtained for tree projected area using direct sequential simulation. Tree projected area simulations were used to improve spatial prediction of V, more difficult and more expensive to obtain, taking advantage of the high linear correlation between both variables (rxy = 0.72, p < 0.001). Thus, direct sequential cosimulation was employed to predict the spatial distribution of V, obtaining 100 geostatistical realizations of V. In order to estimate the potential reduction of pesticide use in the farm with variable rate treatments, two cut-off values of V were considered (50 and 100 m3crown volume). Local uncertainty, understood as the probability of each tree belonging to a given crown volume interval was determined. Probability maps were further transformed to morphological maps and finally to variable prescription maps. Two scenarios with 2 and 3 management zones (MZs) were obtained. In comparison with a conventional phytosanitary application, the variable rate treatments could reduce the pesticide amounts by 21.3% with 2 MZs, and by 38% with 3 MZs. The joint use of V and tree projected area in stochastic sequential simulation algorithms has shown to be useful to determine MZs in olive groves.
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Open Access
(Homo)masculinities: dating apps and body image among young gay users in Spain
(Taylor & Francis Group, 2024-02-14) Roig-Mora, Arnau; Ventura, Rafael; Larrea, Olatz; Blanco-Fernández, Vítor
Mobile dating apps (MDAs) generate spaces where masculinities are (co)produced and reproduced, acting as platforms that define the standards of such masculinities. The objective of this article is to understand the role that MDAs play among young users in the construction of masculinity through body image. The data were collected from 40 semi-structured interviews to male users of MDAs, divided in four groups of age (18–25 and 40+ years old) and sexuality (gay and heterosexual) to compare their experiences and discourses. Results show that, despite muscularity being viewed as a sign of status in all groups and very prevalent in the gay group, users challenge its hegemony by questioning the use of enhancement drugs and the cult-like mentality of muscular users. Gay interviewees also discuss the prevalence of objectification and sexualization in gay culture, but younger users talk about challenging them in their self-presentation. Finally, age seems to give confidence to heterosexual users, while the reverse happens in our gay group. However, in their answers, age and socio-economic status are sometimes conflated.
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Embargo
Beyond representation: negotiating realism and the positive impact of media narratives with trans audiences
(Oxford University Press, 2024-11-08) Villegas Simón, Isabel; Sánchez-Soriano, Juan-José; Ventura, Rafael
The growing presence of trans people in popular culture, including television series, is a well-established fact. However, its broader social impact and particularly consideration of what constitutes a positive representation of the trans community has received little attention from academic literature. This research addresses this gap by focusing on the experiences and interpretations of trans individuals regarding the way they are portrayed in TV series. It does so by conducting a qualitative study of 19 trans Spaniards who participated in two focus groups and nine semi-structured interviews. The findings indicate that the participants view their increased representation as a form of retribution for past under-representation. They also associate positive representation with realism, with two of their primary areas of concern being the need to depict authentic situations and individuals, and lack of involvement of trans people in the creative process. Ultimately, this research highlights the role of television series as amplifiers of trans experiences, voices and stories.