http://hdl.handle.net/2117/221 Mon, 20 May 2013 05:20:59 GMT 2013-05-20T05:20:59Z webmaster.bupc@upc.edu Universitat Politècnica de Catalunya. Servei de Biblioteques i Documentació no http://hdl.handle.net/2117/19094 Title: Comportamiento y propiedades de las fibras de polilactida (PLA) durante su procesado y uso Authors: Cayuela Marín, Diana; Manich Bou, Albert M. Fri, 03 May 2013 13:04:02 GMT http://hdl.handle.net/2117/19094 2013-05-03T13:04:02Z Cayuela Marín, Diana; Manich Bou, Albert M. no http://hdl.handle.net/2117/19033 Title: A new approach to the internal sizing of paper via biotechnological processes Authors: García Ubasart, Jordi; Roncero Vivero, María Blanca; Vidal Lluciá, Teresa Abstract: This work deals with the study of a new biotechnological procedure, employing laccase in combination with hydrophobic compounds, for the biomodification of fibres and the internal sizing of paper. Cellulose fibres from eucalyptus kraft pulp, unbleached and TCF bleached, were incubated with laccase, in combination with a series of hydrophobes. Laccase treatments of cellulose fibres with lauryl gallate conferred the lowest level of water penetration in handsheets. It was observed that the hydrophobization of paper was not possible using the hidrophobe alone. The coupling of lauryl gallate onto cellulose fibres was firstly denoted by kappa number analysis, and further demonstrated by IR spectroscopy. The internal sizing of paper proved to be effective regardless the lignin content of eucalyptus fibres Mon, 29 Apr 2013 12:35:29 GMT http://hdl.handle.net/2117/19033 2013-04-29T12:35:29Z García Ubasart, Jordi; Roncero Vivero, María Blanca; Vidal Lluciá, Teresa no This work deals with the study of a new biotechnological procedure, employing laccase in combination with hydrophobic compounds, for the biomodification of fibres and the internal sizing of paper. Cellulose fibres from eucalyptus kraft pulp, unbleached and TCF bleached, were incubated with laccase, in combination with a series of hydrophobes. Laccase treatments of cellulose fibres with lauryl gallate conferred the lowest level of water penetration in handsheets. It was observed that the hydrophobization of paper was not possible using the hidrophobe alone. The coupling of lauryl gallate onto cellulose fibres was firstly denoted by kappa number analysis, and further demonstrated by IR spectroscopy. The internal sizing of paper proved to be effective regardless the lignin content of eucalyptus fibres http://hdl.handle.net/2117/18998 Title: Effect of the laccase mediator system on the fibre properties of TCF bleached kraft pulp Authors: Cadena Chamorro, Edith Marleny; Cusola Aumedes, Oriol; Vidal Lluciá, Teresa; Torres López, Antonio Luis Abstract: The application of the laccase mediator system (L stage) to TCF bleached pulp from Eucalyptus globulus with a low residual lignin content provides useful information about its effect in the hexenuronic acids content, functional groups (carboxyl and carbonyl) and electrokinetic properties as ζ potential and surface charge. The use of laccase from Trametes villosa in combination with the mediator 1- hydroxybenzotriazole (HBT) produces an oxidation of the cellulose to carbonyl groups, and reduced the amount of carboxyl groups present in TCF pulp through partial removal of hexenuronic acids from it. This result can open up new prospects for increasing brightness stability. Additionally, the laccase mediator system modifies the surface charge and ζ potential of the fibre suspension for the removal de ionizables groups in TCF pulp. The reduction of the carboxyl content additionally alters the charge on fibre surfaces; this may be useful with a view to reducing pulp processing costs since a decreased content in ionizable groups can be expected to reduce consumption of cationic additives used in the production of paper. As regards electrokinetic properties, the laccase mediator system reduces the ζ potential of fibre suspensions by acting on carboxylic and hexenuronic acids. The biomodification of the chemical composition of TCF pulp by the laccase mediator system causes no substantial changes in the properties of the refined pulp (ºSR, %WRV); this indicates that the L treatment does not affect development of the primary effects of refining, and also that it may have a side effect on the fibre-water system by decreasing the proportion of ionizable groups and altering the electrokinetic properties of the pulp Fri, 26 Apr 2013 09:16:28 GMT http://hdl.handle.net/2117/18998 2013-04-26T09:16:28Z Cadena Chamorro, Edith Marleny; Cusola Aumedes, Oriol; Vidal Lluciá, Teresa; Torres López, Antonio Luis no The application of the laccase mediator system (L stage) to TCF bleached pulp from Eucalyptus globulus with a low residual lignin content provides useful information about its effect in the hexenuronic acids content, functional groups (carboxyl and carbonyl) and electrokinetic properties as ζ potential and surface charge. The use of laccase from Trametes villosa in combination with the mediator 1- hydroxybenzotriazole (HBT) produces an oxidation of the cellulose to carbonyl groups, and reduced the amount of carboxyl groups present in TCF pulp through partial removal of hexenuronic acids from it. This result can open up new prospects for increasing brightness stability. Additionally, the laccase mediator system modifies the surface charge and ζ potential of the fibre suspension for the removal de ionizables groups in TCF pulp. The reduction of the carboxyl content additionally alters the charge on fibre surfaces; this may be useful with a view to reducing pulp processing costs since a decreased content in ionizable groups can be expected to reduce consumption of cationic additives used in the production of paper. As regards electrokinetic properties, the laccase mediator system reduces the ζ potential of fibre suspensions by acting on carboxylic and hexenuronic acids. The biomodification of the chemical composition of TCF pulp by the laccase mediator system causes no substantial changes in the properties of the refined pulp (ºSR, %WRV); this indicates that the L treatment does not affect development of the primary effects of refining, and also that it may have a side effect on the fibre-water system by decreasing the proportion of ionizable groups and altering the electrokinetic properties of the pulp http://hdl.handle.net/2117/18887 Title: Cyclodextrin functionalization of several cellulosic substrates for prolonged release of antibacterial agents Authors: Cusola Aumedes, Oriol; Tabary, Nicolas; Naceur Belgacem, Mohamed; Bras, Julien Abstract: Several cellulosic substrates have been surface-functionalized with cyclomaltoheptaose (b-cyclodextrin, b-CD) using citric acid as a crosslinker agent to obtain new surface-modified materials able to release antiseptic molecules over a prolonged period, in view of their use in medical domain. Three different commercial cellulosic substrates were used, namely: (i) an uncoated paper, (ii) a crepe paper, and (iii) a medical bandage. They were successfully grafted by a crosslinked polymer consisting on b-CD molecules as assessed by scanning electron microscopy and Fourier transform infrared spectroscopy analysis. Several time–temperature kinetic cycles were performed to reach the optimum curing parameters. The grafted and nongrafted samples were loaded with chlorhexidine digluconate (digCHX), a widely used antiseptic agent. The drug-delivery kinetics of the encapsulated digCHX was carried out by immersing the sample under investigation into an aqueous medium, and the quantity of the released digCHX was measured, as a function of time, by UV spectroscopy. The optimal grafting conditions were established on the basis of the highest weight gain. These samples did not give the best release performance. Nevertheless, several grafted substrates were able to uptake an appreciable amount of active molecules and release them over a prolonged time of about 20 days Fri, 19 Apr 2013 11:04:05 GMT http://hdl.handle.net/2117/18887 2013-04-19T11:04:05Z Cusola Aumedes, Oriol; Tabary, Nicolas; Naceur Belgacem, Mohamed; Bras, Julien no Several cellulosic substrates have been surface-functionalized with cyclomaltoheptaose (b-cyclodextrin, b-CD) using citric acid as a crosslinker agent to obtain new surface-modified materials able to release antiseptic molecules over a prolonged period, in view of their use in medical domain. Three different commercial cellulosic substrates were used, namely: (i) an uncoated paper, (ii) a crepe paper, and (iii) a medical bandage. They were successfully grafted by a crosslinked polymer consisting on b-CD molecules as assessed by scanning electron microscopy and Fourier transform infrared spectroscopy analysis. Several time–temperature kinetic cycles were performed to reach the optimum curing parameters. The grafted and nongrafted samples were loaded with chlorhexidine digluconate (digCHX), a widely used antiseptic agent. The drug-delivery kinetics of the encapsulated digCHX was carried out by immersing the sample under investigation into an aqueous medium, and the quantity of the released digCHX was measured, as a function of time, by UV spectroscopy. The optimal grafting conditions were established on the basis of the highest weight gain. These samples did not give the best release performance. Nevertheless, several grafted substrates were able to uptake an appreciable amount of active molecules and release them over a prolonged time of about 20 days http://hdl.handle.net/2117/18618 Title: The PVP/VI copolymer dye transfer inhibition agent during the washing of the polyester fabric Authors: Carrión Fité, Francisco Javier Abstract: The objective of this research was to study the effect of the copolymer polyvinylpyrrolidone/vinylimidazole (PVP/VI) for use as a dye transfer inhibitor (DTI) during the washing of dyed polyester fabric, depending on the detergent components. The DTI was used to find its efficiency during repeated washings of polyester fabric dyed with disperse dyes. At the same time, its efficiency was tested fer preventing dye migration to other fabrics, such as polyester, cellulose diacetate, acrylic, polyamide, cotton and wool. The influence of anionic (SDBS) and non-ionic (alkyl ethoxylates with 6 EO-groups) surfactants in different proportions and with zeolite as a builder and the aforementioned DTI was tested. Results of CIELAB colour differences were obtained for the dyed and undyed polyester fabrics after five washings Thu, 04 Apr 2013 13:50:03 GMT http://hdl.handle.net/2117/18618 2013-04-04T13:50:03Z Carrión Fité, Francisco Javier no The objective of this research was to study the effect of the copolymer polyvinylpyrrolidone/vinylimidazole (PVP/VI) for use as a dye transfer inhibitor (DTI) during the washing of dyed polyester fabric, depending on the detergent components. The DTI was used to find its efficiency during repeated washings of polyester fabric dyed with disperse dyes. At the same time, its efficiency was tested fer preventing dye migration to other fabrics, such as polyester, cellulose diacetate, acrylic, polyamide, cotton and wool. The influence of anionic (SDBS) and non-ionic (alkyl ethoxylates with 6 EO-groups) surfactants in different proportions and with zeolite as a builder and the aforementioned DTI was tested. Results of CIELAB colour differences were obtained for the dyed and undyed polyester fabrics after five washings http://hdl.handle.net/2117/18544 Title: Self-video recording for the integration and assessment of generic competencies Authors: Masip Álvarez, Albert; Hervada Sala, Carme; Pàmies Gómez, Teresa; Arias Pujol, Antoni; Jaen Fernandez, Carles; Rodríguez Sorigué, M. Cristina; Romero Durán, David; Nejjari Akhi-Elarab, Fatiha; Álvarez del Castillo, María Dolores; Roca Lefler, Marta; Hernández Farràs, Jorge; Montferrer Liñan, Raul Abstract: This document presents the use of a self-video-recording service for the integration and assessment of certain generic competences (oral and written communication, teamwork and third (English) language) in all degree programs related to the Industrial area at the Terrassa School of Engineering (EET). The resulting service allows to carry out the assessment through active and collaborative learning methodologies using ICT as a support, becoming an educational resource where students are encouraged to evaluate their own activity, individually and in groups (co-evaluation), and with which the faculty can enhance certain sections of the syllabus while also evaluating generic competences. This paper outlines the rationale and design of the system based on self-recording-video that assists work on some generic competences. A preliminary experience has taken place and it has been carried out by volunteer students and some professors from the promoting team. It consisted of following all steps to obtain the video-recording as a result and fulfil the further assessment. Preparing the defence of the final project career, explaining the way a problem is faced are examples of use of the service endowed to assist the assessment of some generic competences. A good number of students and professors have participated in this preliminary experiment carried out on some subjects and in which oral effective communication will be assessed. A specific rubric for the assessment of generic competences has been used both for students and faculty. There is a summary of qualitative feedback from both students and instructors, and where several issues related to improving the self-assessment and self-video-recording system, are discussed. Finally, a survey is proposed, whose results will be helpful for its improvement. Tue, 02 Apr 2013 14:02:57 GMT http://hdl.handle.net/2117/18544 2013-04-02T14:02:57Z Masip Álvarez, Albert; Hervada Sala, Carme; Pàmies Gómez, Teresa; Arias Pujol, Antoni; Jaen Fernandez, Carles; Rodríguez Sorigué, M. Cristina; Romero Durán, David; Nejjari Akhi-Elarab, Fatiha; Álvarez del Castillo, María Dolores; Roca Lefler, Marta; Hernández Farràs, Jorge; Montferrer Liñan, Raul no This document presents the use of a self-video-recording service for the integration and assessment of certain generic competences (oral and written communication, teamwork and third (English) language) in all degree programs related to the Industrial area at the Terrassa School of Engineering (EET). The resulting service allows to carry out the assessment through active and collaborative learning methodologies using ICT as a support, becoming an educational resource where students are encouraged to evaluate their own activity, individually and in groups (co-evaluation), and with which the faculty can enhance certain sections of the syllabus while also evaluating generic competences. This paper outlines the rationale and design of the system based on self-recording-video that assists work on some generic competences. A preliminary experience has taken place and it has been carried out by volunteer students and some professors from the promoting team. It consisted of following all steps to obtain the video-recording as a result and fulfil the further assessment. Preparing the defence of the final project career, explaining the way a problem is faced are examples of use of the service endowed to assist the assessment of some generic competences. A good number of students and professors have participated in this preliminary experiment carried out on some subjects and in which oral effective communication will be assessed. A specific rubric for the assessment of generic competences has been used both for students and faculty. There is a summary of qualitative feedback from both students and instructors, and where several issues related to improving the self-assessment and self-video-recording system, are discussed. Finally, a survey is proposed, whose results will be helpful for its improvement. http://hdl.handle.net/2117/18300 Title: MODSIMTex Authors: Tornero García, José Antonio Thu, 14 Mar 2013 13:46:50 GMT http://hdl.handle.net/2117/18300 2013-03-14T13:46:50Z Tornero García, José Antonio no http://hdl.handle.net/2117/18297 Title: Application of surface enzyme treatments using laccase and a hydrophobic compound to paper-based media Authors: Cusola Aumedes, Oriol; Valls Vidal, Cristina; Vidal Lluciá, Teresa; Roncero Vivero, María Blanca Abstract: A new approach for the hydrophobization of finished cellulosic substrates based on a previously reported enzymatic technique is proposed. Commercial finished paper was hydrophobized by using laccase from Trametes villosa in combination with lauryl gallate (LG) as hydrophobic compound. The efficiency of the method was increased by the use of a lignosulfonate as a natural dispersant to improve the surface distribution of LG on the paper, raise its hydrophobicity and help preserve the enzyme activity. No similar threefold effect from a single compound for the improvement of enzymatic treatments was previously reported. The influence of processing conditions including the LG dose, treatment time and temperature was also examined, resulting in further increased hydrophobicity. Efficient fiber bonding and chemical functionalization were confirmed by thorough washing and Soxhlet extraction of the paper. As shown here for the first time, enzyme treatments have the potential to improve the surface hydrophobicity of paper-based media Thu, 14 Mar 2013 11:44:20 GMT http://hdl.handle.net/2117/18297 2013-03-14T11:44:20Z Cusola Aumedes, Oriol; Valls Vidal, Cristina; Vidal Lluciá, Teresa; Roncero Vivero, María Blanca no A new approach for the hydrophobization of finished cellulosic substrates based on a previously reported enzymatic technique is proposed. Commercial finished paper was hydrophobized by using laccase from Trametes villosa in combination with lauryl gallate (LG) as hydrophobic compound. The efficiency of the method was increased by the use of a lignosulfonate as a natural dispersant to improve the surface distribution of LG on the paper, raise its hydrophobicity and help preserve the enzyme activity. No similar threefold effect from a single compound for the improvement of enzymatic treatments was previously reported. The influence of processing conditions including the LG dose, treatment time and temperature was also examined, resulting in further increased hydrophobicity. Efficient fiber bonding and chemical functionalization were confirmed by thorough washing and Soxhlet extraction of the paper. As shown here for the first time, enzyme treatments have the potential to improve the surface hydrophobicity of paper-based media http://hdl.handle.net/2117/18230 Title: Laccase from Pycnoporus cinnabarinus and phenolic compounds: can the efficiency of an enzyme mediator for delignifying kenaf pulp be predicted? Authors: Andreu Terrén, Glòria; Vidal Lluciá, Teresa Abstract: In this work, kenaf pulp was delignified by using laccase in combination with various redox mediators and the efficiency of the different laccase–mediator systems assessed in terms of the changes in pulp properties after bleaching. The oxidative ability of the individual mediators used (acetosyringone, syringaldehyde, p-coumaric acid, vanillin and actovanillone) and the laccase–mediator systems was determined by monitoring the oxidation–reduction potential (ORP) during process. The results confirmed the production of phenoxy radicals of variable reactivity and stressed the significant role of lignin structure in the enzymatic process. Although changes in ORP were correlated with the oxidative ability of the mediators, pulp properties as determined after the bleaching stage were also influenced by condensation and grafting reactions. As shown here, ORP measurements provide a first estimation of the delignification efficiency of a laccase–mediator system. Tue, 12 Mar 2013 16:04:36 GMT http://hdl.handle.net/2117/18230 2013-03-12T16:04:36Z Andreu Terrén, Glòria; Vidal Lluciá, Teresa no Kenaf, Laccase, Phenolic mediators, Oxidation–reduction potential In this work, kenaf pulp was delignified by using laccase in combination with various redox mediators and the efficiency of the different laccase–mediator systems assessed in terms of the changes in pulp properties after bleaching. The oxidative ability of the individual mediators used (acetosyringone, syringaldehyde, p-coumaric acid, vanillin and actovanillone) and the laccase–mediator systems was determined by monitoring the oxidation–reduction potential (ORP) during process. The results confirmed the production of phenoxy radicals of variable reactivity and stressed the significant role of lignin structure in the enzymatic process. Although changes in ORP were correlated with the oxidative ability of the mediators, pulp properties as determined after the bleaching stage were also influenced by condensation and grafting reactions. As shown here, ORP measurements provide a first estimation of the delignification efficiency of a laccase–mediator system. http://hdl.handle.net/2117/18215 Title: Chicken feathers based composites: a life cycle assessment Authors: Molins Durán, Gemma; Álvarez del Castillo, María Dolores; Garrido Soriano, Núria; Macanàs de Benito, Jorge; Carrillo Navarrete, Fernando Abstract: Chicken feathers (CFs) are a waste material generated from poultry industry in large quantities. A composite material constituted of poly lactide and CFs is proposed in order to prepare a biodegradable composite with low environmental impact. In order to evaluate its environmental impact, a Life Cycle Assessment (LCA) is performed. The results show that, from the environmental point of view, the more chicken feathers in the material, the greater is its impact. This is mainly due to the non - inclusion of the impact data regarding CFs current waste management treatments required in accordance with the European Directive CE 1069/2009 (in study) and to the high energy consumption of the pre - treatment stages (cleaning and sanitizing) required to transform CFs waste into a CFs technical material that can be used for the preparation of CFs/PLA composites material, which needs to be optimized. Tue, 12 Mar 2013 14:31:40 GMT http://hdl.handle.net/2117/18215 2013-03-12T14:31:40Z Molins Durán, Gemma; Álvarez del Castillo, María Dolores; Garrido Soriano, Núria; Macanàs de Benito, Jorge; Carrillo Navarrete, Fernando no Chicken feathers (CFs) are a waste material generated from poultry industry in large quantities. A composite material constituted of poly lactide and CFs is proposed in order to prepare a biodegradable composite with low environmental impact. In order to evaluate its environmental impact, a Life Cycle Assessment (LCA) is performed. The results show that, from the environmental point of view, the more chicken feathers in the material, the greater is its impact. This is mainly due to the non - inclusion of the impact data regarding CFs current waste management treatments required in accordance with the European Directive CE 1069/2009 (in study) and to the high energy consumption of the pre - treatment stages (cleaning and sanitizing) required to transform CFs waste into a CFs technical material that can be used for the preparation of CFs/PLA composites material, which needs to be optimized. http://hdl.handle.net/2117/18145 Title: Enzymatic grafting of natural phenols to flax fibres: development of antimicrobial properties Authors: Fillat Latorre, Amanda; Gallardo Román, Óscar; Vidal Lluciá, Teresa; Pastor Blasco, Francisco I. Javier; Díaz Lucea, Pilar; Roncero Vivero, María Blanca Abstract: Unbleached flax fibres for paper production were treated with laccase from Pycnoporus cinnabarinus and low molecular weight phenols (syringaldehyde – SA, acetosyringone – AS and p-coumaric acid – PCA) to evaluate the potential of this treatment to biomodify high cellulose content fibres. After the enzymatic treatment with the phenols, an increase in kappa number was found, probably due to a covalent binding of the phenoxy radicals on fibres. Grafting was more evident in pulps treated with PCA (an increase of 4 kappa number points with respect to the laccase control was achieved). Paper handsheets from treated pulps showed antimicrobial activity against the bacteria tested: Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae. An important reduction on microbial count was obtained after incubation of liquid cultures of the bacteria with grafted handsheets. AS and PCA grafted fibres showed a high antibacterial activity on K. pneumoniae, getting a nearly total growth inhibition. AS fibres also caused a high reduction in bacterial population of P. aeruginosa (97% reduction). Optical properties of handsheets from treated pulps were also determined, showing a brightness decrease and increase in coloration, evaluated by CIE L*a*b* system, caused by the laccase induced grafting of the phenols. The results suggest that these low molecular weight phenols, covalently bound to the flax fibres by the laccase treatment, can act as antimicrobial agents and produce handsheets with antimicrobial activity Fri, 08 Mar 2013 11:09:37 GMT http://hdl.handle.net/2117/18145 2013-03-08T11:09:37Z Fillat Latorre, Amanda; Gallardo Román, Óscar; Vidal Lluciá, Teresa; Pastor Blasco, Francisco I. Javier; Díaz Lucea, Pilar; Roncero Vivero, María Blanca no Unbleached flax fibres for paper production were treated with laccase from Pycnoporus cinnabarinus and low molecular weight phenols (syringaldehyde – SA, acetosyringone – AS and p-coumaric acid – PCA) to evaluate the potential of this treatment to biomodify high cellulose content fibres. After the enzymatic treatment with the phenols, an increase in kappa number was found, probably due to a covalent binding of the phenoxy radicals on fibres. Grafting was more evident in pulps treated with PCA (an increase of 4 kappa number points with respect to the laccase control was achieved). Paper handsheets from treated pulps showed antimicrobial activity against the bacteria tested: Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae. An important reduction on microbial count was obtained after incubation of liquid cultures of the bacteria with grafted handsheets. AS and PCA grafted fibres showed a high antibacterial activity on K. pneumoniae, getting a nearly total growth inhibition. AS fibres also caused a high reduction in bacterial population of P. aeruginosa (97% reduction). Optical properties of handsheets from treated pulps were also determined, showing a brightness decrease and increase in coloration, evaluated by CIE L*a*b* system, caused by the laccase induced grafting of the phenols. The results suggest that these low molecular weight phenols, covalently bound to the flax fibres by the laccase treatment, can act as antimicrobial agents and produce handsheets with antimicrobial activity http://hdl.handle.net/2117/17936 Title: Responses of B-esterase enzymes in oysters (Crassostrea gigas) transplanted to pesticide contaminated bays form the Ebro Delta (NE, Spain) Authors: Ochoa, Victoria; Riva Juan, Mª del Carmen; Faria, Melissa; Barata, Carlos Abstract: Marine bivalves such as oysters are widely used as bioindicators to monitor marine coastal pollution. This study aimed to use B-esterase activity responses in oysters (Crassostrea gigas) cultured in Ebro Delta bays to monitor environmental effects of pesticides. The B esterases investigated were acetylcholinesterase, propionylcholinesterase, and carboxylesterase and their activities were measured in adductor muscle and gills from oysters transplanted in Ebro Delta bays where the are traditionally grown. Enzyme activities were related with physico-chemical parameters and pesticide levels measured in water. Cholinesterase activities measured in gills were unaffected across sites and periods. Conversely, carboxylesterase activities in oyster gills varied across periods and sites and were negatively correlated with residue levels of organophoshporous and carbamate pesticides in water. Therefore, inhibition of carboxylesterase activities can be considered a good indicator of exposure to anti-cholinergic pesticides in oysters Fri, 22 Feb 2013 12:26:45 GMT http://hdl.handle.net/2117/17936 2013-02-22T12:26:45Z Ochoa, Victoria; Riva Juan, Mª del Carmen; Faria, Melissa; Barata, Carlos no Marine bivalves such as oysters are widely used as bioindicators to monitor marine coastal pollution. This study aimed to use B-esterase activity responses in oysters (Crassostrea gigas) cultured in Ebro Delta bays to monitor environmental effects of pesticides. The B esterases investigated were acetylcholinesterase, propionylcholinesterase, and carboxylesterase and their activities were measured in adductor muscle and gills from oysters transplanted in Ebro Delta bays where the are traditionally grown. Enzyme activities were related with physico-chemical parameters and pesticide levels measured in water. Cholinesterase activities measured in gills were unaffected across sites and periods. Conversely, carboxylesterase activities in oyster gills varied across periods and sites and were negatively correlated with residue levels of organophoshporous and carbamate pesticides in water. Therefore, inhibition of carboxylesterase activities can be considered a good indicator of exposure to anti-cholinergic pesticides in oysters http://hdl.handle.net/2117/17932 Title: Use of cyclic voltammetry as an effective tool for selecting effcient enhancers for oxidative bioprocesses: importance of pH Authors: Aracri, Elisabetta; Tzanov, Tzanko; Vidal Lluciá, Teresa Abstract: Seven natural phenols and two synthetic compounds were evaluated by means of cyclic voltammetry as enhancers for the oxidation of the lignin model compound veratryl alcohol (VAl) and a sulfonated lignin (SL). Their electrochemical behaviors and catalytic efficiencies (CEs) against both substrates were assessed as a function of pH. A general increase in CE of the phenols was for the first time observed in the oxidation of VAl at pH 7 and 8. Methyl syringate (MS), syringic acid (SRC), and syringaldehyde (SRD) exhibited the highest CEs against VAl among the studied phenolic compounds despite the reduced stabilities of their phenoxy radicals. This was a result of favorable stability−reactivity balances, which were apparently influenced by both the chemical structures of the enhancers and the experimental conditions. Violuric acid (VAc) proved the most efficient compound in oxidizing lignin, followed by SRD and MS, which showed regeneration in the interval of pHs studied Fri, 22 Feb 2013 11:50:22 GMT http://hdl.handle.net/2117/17932 2013-02-22T11:50:22Z Aracri, Elisabetta; Tzanov, Tzanko; Vidal Lluciá, Teresa no Seven natural phenols and two synthetic compounds were evaluated by means of cyclic voltammetry as enhancers for the oxidation of the lignin model compound veratryl alcohol (VAl) and a sulfonated lignin (SL). Their electrochemical behaviors and catalytic efficiencies (CEs) against both substrates were assessed as a function of pH. A general increase in CE of the phenols was for the first time observed in the oxidation of VAl at pH 7 and 8. Methyl syringate (MS), syringic acid (SRC), and syringaldehyde (SRD) exhibited the highest CEs against VAl among the studied phenolic compounds despite the reduced stabilities of their phenoxy radicals. This was a result of favorable stability−reactivity balances, which were apparently influenced by both the chemical structures of the enhancers and the experimental conditions. Violuric acid (VAc) proved the most efficient compound in oxidizing lignin, followed by SRD and MS, which showed regeneration in the interval of pHs studied http://hdl.handle.net/2117/17794 Title: Instrumento quirúrgico de sutura para anastomosis automática del tubo digestivo Authors: Tornero García, José Antonio; Suárez Feijóo, Raúl; Cano Casas, Francesc; Montaño Sarria, Andrés Felipe; López Cano, Manuel Abstract: En la cirugía digestiva, una anastomosis del intestino consiste en la reconstrucción del tubo digestivo por unión de dos cabos tras la resección de una porción del mismo. Este procedimiento, de común aplicación en diversos tipos de intervención quirúrgica se realiza actualmente mediante la aplicación de grapas metálicas debido a la complejidad inherente de la realización de una sutura manual. La automatización del proceso de sutura mediante un dispositivo diseñado a tal efecto supondría una notable mejora en el procedimiento quirúrgico asociado y posteriormente en la calidad de vida del paciente, ya que las grapas metálicas empleadas actualmente presentan diversos inconvenientes. El diseño de este dispositivo presenta gran complejidad debido al rigor de los requisitos funcionales y a la complejidad del entorno de funcionamiento así como las características de los materiales que intervienen en el proceso.En el presente trabajo se describe el desarrollo de un prototipo de dispositivo para anastomosis automática mediante sutura, evaluando su funcionalidad a nivel de laboratorio, con objeto de probar su validez Fri, 15 Feb 2013 13:50:44 GMT http://hdl.handle.net/2117/17794 2013-02-15T13:50:44Z Tornero García, José Antonio; Suárez Feijóo, Raúl; Cano Casas, Francesc; Montaño Sarria, Andrés Felipe; López Cano, Manuel no En la cirugía digestiva, una anastomosis del intestino consiste en la reconstrucción del tubo digestivo por unión de dos cabos tras la resección de una porción del mismo. Este procedimiento, de común aplicación en diversos tipos de intervención quirúrgica se realiza actualmente mediante la aplicación de grapas metálicas debido a la complejidad inherente de la realización de una sutura manual. La automatización del proceso de sutura mediante un dispositivo diseñado a tal efecto supondría una notable mejora en el procedimiento quirúrgico asociado y posteriormente en la calidad de vida del paciente, ya que las grapas metálicas empleadas actualmente presentan diversos inconvenientes. El diseño de este dispositivo presenta gran complejidad debido al rigor de los requisitos funcionales y a la complejidad del entorno de funcionamiento así como las características de los materiales que intervienen en el proceso.En el presente trabajo se describe el desarrollo de un prototipo de dispositivo para anastomosis automática mediante sutura, evaluando su funcionalidad a nivel de laboratorio, con objeto de probar su validez http://hdl.handle.net/2117/17489 Title: Bleached dissolving pulps applying laccase treatments Authors: Quintana, Elisabet; Valls Vidal, Cristina; Roncero Vivero, María Blanca Abstract: A biobleaching sequence, using a laccase enzyme (Trametes Villosa) in combination with different mediators, was applied to softwood dissolving cellulose in order to study its bleaching efficiency and its potential in terms of kappa number, ISO brightness and viscosity. The tested mediators were classified as synthetic compounds such as HBT (1-hydroxybenzotriazole) and VA (violuric acid), and as natural compounds such as SA (syringaldehyde) and pCA (p-coumaric acid). The influence of the enzymatic stage in the bleaching sequence was compared with a control treatment and also with a conventional alkaline hydrogen peroxide stage. The contribution of L (laccasemediator) stage on the effluent properties is important for evaluating and minimizing its environmental impact. Therefore, effluent properties (COD, colour, residual enzyme activity and toxicity) were determined. Laccase-VA system showed the most promising results in reducing kappa number and increasing brightness without detriment to viscosity Wed, 23 Jan 2013 10:51:06 GMT http://hdl.handle.net/2117/17489 2013-01-23T10:51:06Z Quintana, Elisabet; Valls Vidal, Cristina; Roncero Vivero, María Blanca no A biobleaching sequence, using a laccase enzyme (Trametes Villosa) in combination with different mediators, was applied to softwood dissolving cellulose in order to study its bleaching efficiency and its potential in terms of kappa number, ISO brightness and viscosity. The tested mediators were classified as synthetic compounds such as HBT (1-hydroxybenzotriazole) and VA (violuric acid), and as natural compounds such as SA (syringaldehyde) and pCA (p-coumaric acid). The influence of the enzymatic stage in the bleaching sequence was compared with a control treatment and also with a conventional alkaline hydrogen peroxide stage. The contribution of L (laccasemediator) stage on the effluent properties is important for evaluating and minimizing its environmental impact. Therefore, effluent properties (COD, colour, residual enzyme activity and toxicity) were determined. Laccase-VA system showed the most promising results in reducing kappa number and increasing brightness without detriment to viscosity