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International Journal of Food Microbiology | 2001

Effect of high oxygen modified atmosphere packaging on microbial growth and sensorial qualities of fresh-cut produce

Liesbeth Jacxsens; Frank Devlieghere; Caroline Van der Steen; Johan Debevere

The application of High Oxygen Atmospheres (HOA) (i.e. > 70% O2) for packaging ready-to-eat vegetables was evaluated as an alternative technique for low O2 Equilibrium Modified Atmosphere (EMA) packaging (3% O2-5% CO2-balance N2) for respiring products. Comparative experiments between both techniques were performed in-vitro and in-vivo. Typical spoilage causing microorganisms (Pseudomonas fluorescens, Candida lambica), the moulds Botrytis cinerea, Aspergillus flavus and the opportunistic psychrotrophic human pathogenic microorganism associated with refrigerated minimally processed vegetables. Aeromonas caviae (HG4), showed a retarded growth during the conducted in-vitro studies at 4 degrees C in 70%, 80% and 95% O2 as examples of HOA compared to the in-vitro experiments in 5% O2 (as example of EMA packaging) and the effect was more pronounced in 95% O2. The effect of the high O2-concentrations on the human pathogen Listeria monocytogenes resulted in an extended lag phase (95% O2). The plant pathogen Erwinia carotovora was increasingly stimulated by increasing high O2-concentrations. During a storage experiment of three types of ready-to-eat vegetables (mushroom slices, grated celeriac and shredded chicory endive), which are sensitive to enzymatic browning and microbial spoilage, the effect of EMA and HOA (95% O2-5% N2) on their quality and shelf life was compared. High O2 atmospheres were found to be particularly effective in inhibiting enzymatic browning of the tested vegetables. Also, the microbial quality was better as a reduction in yeast growth was observed. The HOA can be applied as an alternative for low O2 modified atmospheres for some specific types of ready-to-eat vegetables, sensitive to enzymatic browning and spoilage by yeasts.


Journal of Food Protection | 1999

Behavior of Listeria monocytogenes and Aeromonas spp. on fresh-cut produce packaged under equilibrium-modified atmosphere.

Liesbeth Jacxsens; Frank Devlieghere; P Falcato; Johan Debevere

Storage experiments were conducted to follow the behavior of pathogens on fresh-cut vegetables (trimmed brussels sprouts, grated carrots, shredded iceberg lettuce, and shredded chicory endives) packaged under an equilibrium-modified atmosphere (EMA) (2 to 3% O2, 2 to 3% CO2, and 94 to 96% N2) and stored at 7 degrees C. As a comparison, fresh-cut vegetables were also packaged in a perforated high-barrier film (air conditions) and stored at 7 degrees C. In a first step, the shelf life of the vegetables in the two kinds of packages was determined by evaluating the microbiological quality as well as the sensorial quality (appearance, taste, and odor). In general, sensorial properties were faster in limiting the shelf life than microbiological criteria. The shelf life of the vegetables stored under an EMA was extended by 50% or more, compared with the air-stored vegetables. In a second storage experiment, the four fresh-cut vegetables were inoculated with a cocktail of psychrotrophic pathogens (Listeria monocytogenes, Aeromonas caviae [HG4]) and A. bestiarum (HG2) before packaging under an EMA and air at 7 degrees C. The inoculated pathogens were more influenced by the type of vegetable than by the type of atmosphere. No growth was detected on the brussels sprouts or on carrots (L. monocytogenes). Aeromonas spp. had a higher growth rate than L. monocytogenes on the shredded chicory endives and shredded iceberg lettuce at 7 degrees C.


Postharvest Biology and Technology | 2002

Combining high oxygen atmospheres with low oxygen modified atmosphere packaging to improve the keeping quality of strawberries and raspberries

C Van der Steen; Liesbeth Jacxsens; Frank Devlieghere; Johan Debevere

Abstract The quality of strawberries and raspberries, packaged in different consumer-sized systems was assessed. The following consumer-sized packaging systems for strawberries and raspberries are compared: (1) the conventional method of packaging in a macro-perforated high-barrier film (AIR), (2) low O 2 modified atmosphere (i.e. 3–5 kPa O 2 and 5–10 kPa CO 2 -balance N 2 ), (3) high O 2 modified atmosphere (HOA, i.e. >70 kPa O 2 -balance N 2 ): HOA in a high-barrier film and (4) HOA in a MA film with an adjusted film permeability. The high O 2 atmosphere in the MA film reached steady-state after 5 days at about 3 kPa O 2 and 5 kPa CO 2 . The O 2 content in the high-barrier film package remained above 21 kPa O 2 during the first 5 days of storage, but then decreased to anaerobic conditions, resulting in off-flavors and odors. To avoid an accumulation of ethylene inside the high-barrier package, an ethylene adsorbing monolayer was added. Shelf life of strawberries and raspberries given the AIR treatment was limited by growth of moulds, rather than by sensory unacceptance. On the other hand, sensory properties limited the shelf life of the fruit packaged under MA. The initial high O 2 atmospheres retarded the growth of moulds. However, when O 2 was depleted and CO 2 had accumulated in the barrier film, sensory quality (odor, taste and firmness) declined. In the MA film, the inhibitory effect on mould growth was maintained, due to the initial high O 2 levels.


International Journal of Food Microbiology | 2002

Predictive modelling for packaging design: equilibrium modified atmosphere packages of fresh-cut vegetables subjected to a simulated distribution chain.

Liesbeth Jacxsens; Frank Devlieghere; Johan Debevere

The impact of temperature fluctuations in a simulated cold distribution chain, typical of commercial practice, was investigated on both the microbial and sensorial quality of equilibrium modified atmosphere (EMA) packaged minimally processed vegetables. The internal O2 concentration of the designed packages could be predicted for the different steps of the simulated distribution chain by applying an integrated mathematical system. The internal atmosphere in the packages remained in its aerobic range during storage in the chain due to the application of high permeable packaging films for O2 and CO2. Spoilage microorganisms were proliferating fast on minimally processed bell peppers and lettuce. Yeasts showed to be the shelf-life limiting group. Visual properties limited the sensorial shelf-life. Listeria monocytogenes was able to multiply on cucumber slices, survived on minimally processed lettuce and decreased in number on bell peppers due to the combination of low pH and refrigeration. Aeromonas caviae was multiplying on both cucumber slices and mixed lettuce, but was as well inhibited by the low pH of bell peppers. Storage temperature control was found to be of paramount importance for the microbial (spoilage and safety) and sensorial quality evaluation of EMA-packaged minimally processed vegetables.


International Journal of Food Microbiology | 2009

Prevalence and challenge tests of Listeria monocytogenes in Belgian produced and retailed mayonnaise-based deli-salads, cooked meat products and smoked fish between 2005 and 2007

Mieke Uyttendaele; Pieter Busschaert; Antonio Valero; A.H. Geeraerd; An Vermeulen; Liesbeth Jacxsens; K.K. Goh; A. De Loy; J.F. Van Impe; Frank Devlieghere

Processed ready-to-eat (RTE) foods with a prolonged shelf-life under refrigeration are at risk products for listeriosis. This manuscript provides an overview of prevalence data (n=1974) and challenge tests (n=299) related to Listeria monocytogenes for three categories of RTE food i) mayonnaise-based deli-salads (1187 presence/absence tests and 182 challenge tests), ii) cooked meat products (639 presence/absence tests and 92 challenge tests), and iii) smoked fish (90 presence/absence tests and 25 challenge tests), based on data records obtained from various food business operators in Belgium in the frame of the validation and verification of their HACCP plans over the period 2005-2007. Overall, the prevalence of L. monocytogenes in these RTE foods in the present study was lower compared to former studies in Belgium. For mayonnaise-based deli-salads, in 80 out of 1187 samples (6.7%) the pathogen was detected in 25 g. L. monocytogenes positive samples were often associated with smoked fish deli-salads. Cooked meat products showed a 1.1% (n=639) prevalence of the pathogen. For both food categories, numbers per gram never exceeded 100 CFU. L. monocytogenes was detected in 27.8% (25/90) smoked fish samples, while 4/25 positive samples failed to comply to the 100 CFU/g limit set out in EU Regulation 2073/2005. Challenge testing showed growth potential in 18/182 (9.9%) deli-salads and 61/92 (66%) cooked meat products. Nevertheless, both for deli-salads and cooked meat products, appropriate product formulation and storage conditions based upon hurdle technology could guarantee no growth of L. monocytogenes throughout the shelf-life as specified by the food business operator. Challenge testing of smoked fish showed growth of L. monocytogenes in 12/25 samples stored for 3-4 weeks at 4 degrees C. Of 45 (non-inoculated) smoked fish samples (13 of which were initially positive in 25 g) which were subjected to shelf-life testing, numbers exceeded 100 CFU/g in only one sample after storage until the end of shelf-life. Predictive models, dedicated to and validated for a particular food category, taking into account the inhibitory effect of various factors in hurdle technology, provided predictions of growth potential of L. monocytogenes corresponding to observed growth in challenge testing. Based on the combined prevalence data and growth potential, mayonnaise-based deli-salads and cooked meat products can be classified as intermediate risk foods, smoked fish as a high risk food.


Critical Reviews in Food Science and Nutrition | 2015

Pre- and Postharvest Preventive Measures and Intervention Strategies to Control Microbial Food Safety Hazards of Fresh Leafy Vegetables

María I. Gil; María V. Selma; Trevor V. Suslow; Liesbeth Jacxsens; Mieke Uyttendaele; Ana Allende

This review includes an overview of the most important preventive measures along the farm to fork chain to prevent microbial contamination of leafy greens. It also includes the technological and managerial interventions related to primary production, postharvest handling, processing practices, distribution, and consumer handling to eliminate pathogens in leafy greens. When the microbiological risk is already present, preventive measures to limit actual contamination events or pathogen survival are considered intervention strategies. In codes of practice the focus is mainly put on explaining preventive measures. However, it is also important to establish more focused intervention strategies. This review is centered mainly on leafy vegetables as the commodity identified as the highest priority in terms of fresh produce microbial safety from a global perspective. There is no unique preventive measure or intervention strategy that could be applied at one point of the food chain. We should encourage growers of leafy greens to establish procedures based on the HACCP principles at the level of primary production. The traceability of leafy vegetables along the chain is an essential element in ensuring food safety. Thus, in dealing with the food safety issues associated with fresh produce it is clear that a multidisciplinary farm to fork strategy is required.


International Journal of Food Microbiology | 2009

A Microbial Assessment Scheme to measure microbial performance of Food Safety Management Systems

Liesbeth Jacxsens; Jamal Kussaga; P.A. Luning; M. van der Spiegel; Frank Devlieghere; Mieke Uyttendaele

A Food Safety Management System (FSMS) implemented in a food processing industry is based on Good Hygienic Practices (GHP), Hazard Analysis Critical Control Point (HACCP) principles and should address both food safety control and assurance activities in order to guarantee food safety. One of the most emerging challenges is to assess the performance of a present FSMS. The objective of this work is to explain the development of a Microbial Assessment Scheme (MAS) as a tool for a systematic analysis of microbial counts in order to assess the current microbial performance of an implemented FSMS. It is assumed that low numbers of microorganisms and small variations in microbial counts indicate an effective FSMS. The MAS is a procedure that defines the identification of critical sampling locations, the selection of microbiological parameters, the assessment of sampling frequency, the selection of sampling method and method of analysis, and finally data processing and interpretation. Based on the MAS assessment, microbial safety level profiles can be derived, indicating which microorganisms and to what extent they contribute to food safety for a specific food processing company. The MAS concept is illustrated with a case study in the pork processing industry, where ready-to-eat meat products are produced (cured, cooked ham and cured, dried bacon).


International Journal of Food Microbiology | 2010

Food safety performance indicators to benchmark food safety output of food safety management systems

Liesbeth Jacxsens; Mieke Uyttendaele; Frank Devlieghere; Jordi Rovira; S. Oses Gomez; P.A. Luning

There is a need to measure the food safety performance in the agri-food chain without performing actual microbiological analysis. A food safety performance diagnosis, based on seven indicators and corresponding assessment grids have been developed and validated in nine European food businesses. Validation was conducted on the basis of an extensive microbiological assessment scheme (MAS). The assumption behind the food safety performance diagnosis is that food businesses which evaluate the performance of their food safety management system in a more structured way and according to very strict and specific criteria will have a better insight in their actual microbiological food safety performance, because food safety problems will be more systematically detected. The diagnosis can be a useful tool to have a first indication about the microbiological performance of a food safety management system present in a food business. Moreover, the diagnosis can be used in quantitative studies to get insight in the effect of interventions on sector or governmental level.


Toxicology Letters | 2013

Human exposure to mycotoxins and their masked forms through cereal-based foods in Belgium

Marthe De Boevre; Liesbeth Jacxsens; Carl Lachat; Mia Eeckhout; José Diana Di Mavungu; Kris Audenaert; Peter Maene; Geert Haesaert; Patrick Kolsteren; Bruno De Meulenaer; Sarah De Saeger

In the present study, a quantitative dietary exposure assessment of mycotoxins and their masked forms was conducted on a national representative sample of the Belgian population using the contamination data of cereal-based foods. Cereal-based food products (n=174) were analysed for the occurrence of deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, zearalenone, α-zearalenol, β-zearalenol, T-2-toxin, HT-2-toxin, and their respective masked forms, including, deoxynivalenol-3-glucoside, zearalenone-4-glucoside, α-zearalenol-4-glucoside, β-zearalenol-4-glucoside and zearalenone-4-sulfate. Fibre-enriched bread, bran-enriched bread, breakfast cereals, popcorn and oatmeal were collected in Belgian supermarkets according to a structured sampling plan and analysed during the period from April 2010 to October 2011. The habitual intake of these food groups was estimated from a national representative food intake survey. According to a probabilistic exposure analysis, the mean (and P95) mycotoxin intake for the sum of the deoxynivalenol-equivalents, zearalenone-equivalents, and the sum of HT-2-and T-2-toxin for all cereal-based foods was 0.1162 (0.4047, P95), 0.0447 (0.1568, P95) and 0.0258 (0.0924, P95) μg kg(-1)body weight day(-1), respectively. These values were below the tolerable daily intake (TDI) levels for deoxynivalenol, zearalenone and the sum of T-2 and HT-2 toxin (1.0, 0.25 and 0.1 μg kg(-1)body weight day(-1), respectively). The absolute level exceeding the TDI for all cereal-based foods was calculated, and recorded 0.85%, 2.75% and 4.11% of the Belgian population, respectively.


Journal of Food Protection | 2002

Effect of Superatmospheric Oxygen Packaging on Sensorial Quality, Spoilage, and Listeria monocytogenes and Aeromonas caviae Growth in Fresh Processed Mixed Salads

Ana Allende; Liesbeth Jacxsens; Frank Devlieghere; Johan Debevere; Francisco Artés

Tesis llevada a cabo para conseguir el grado de Doctor por la Universidad de Complutense de Madrid.--2018-01-15.--Sobresaliente cum laudeContiene 7 documentos (1. Objetivos, alcance y publicaciones. 2. Registro y codigo) y 5 con el softwareespanolLas ciber amenazas afectan a todo tipo de organizaciones, causando frecuentes y costosos impactos globalmente. Recientemente, han surgido productos de ciberseguro con el potencial de reducir el impacto de los riesgos en el ciberespacio. Sin embargo, aun tienen que madurar. En este articulo presentamos varios modelos de analisis de riesgos que podrian facilitar la implantacion y adopcion de ciberseguros. Estos modelos, descritos como diagramas de influencia y diagramas de influencia bi-agente, aportan un marco para estimar el impacto economico de los ciber riesgos a los que se enfrentan aseguradores y asegurados, asi como tambien para calcular sus estrategias optimas de mitigacion y transferencia del riesgo. EnglishCyber threats affect all kinds of organisations with frequent and costly impacts worldwide. Cyber insurance products have recently emerged with the potential of lowering the impact of cyberspace risks. However, they have yet to mature. In this paper we present several risk analysis models that may facilitate the implementation and adoption of cyber insurance. These models, described in terms of influence diagrams and bi-agent influence diagrams, provide a framework for estimating the economic impact of cyber risks that may face insurers and insurees as well as calculating their optimal risk mitigation and transfer strategies.Trabajo presentado a la III Iberoamerican Conference on Supercritical Fluids celebrada en Cartagena de Indias (Colombia) del 1 al 5 de abril de 2013.Trabajo presentado a la 26th IAEA Fusion Energy Conference, celebrada en Kyoto (Japon) del 17 al 22 de octubre de 2016.The Joint Iberian Meeting on Atomic and Molecular Physics (IBER), Barcelona, September 12-14th, 2017. -- http://iber2017.com/index.phpPoster presentado en el 10o Congreso de la Asociacion Iberica de Endocrinologia Comparada AIEC, celebrado en Castellon, Espana, del 23 al 25 de septiembre de 2015Resumen del trabajo presentado a la XI Reunion del Grupo de Microbiologia Molecular, celebrada en Sevilla del 6 al 8 de septiembre de 2016.Chinchilla-Rodriguez, Zaida; Miguel, Sandra; Perianes-Rodriguez, Antonio; Ovalle-Perandones, Antonia; Olmeda-Gomez, Carlos. (2016). Autonomy vs. dependency of scientific collaboration in scientific performance . 21st International Conference on Science and Technology Indicators, STI2016. Valencia, Spain, 14-16 September 2016XXV National Spectroscopy Meeting (XXV RNE), IX Iberian Spectroscopy Conference (IX CIE), Alicante, 20th-22nd July, 2016Resumen del trabajo presentado a la 43rd International Conference on Micro and Nano Engineering (MNE), celebrada en Braga (Portugal) del 18 al 22 de septiembre de 2017.Contiene 7 documentos (1. Objetivos, alcance y publicaciones. 2. Registro, interface y codigo) y 5 con el softwarePoster presentado en el congreso 4th SCARCE International Conference, celebrado en Cadiz, Espana el 25 y 26 de noviembre de 2013We present a Cultural Heritage conceptual data model built under the European INSPIRE ( Infrastructure for Spatial Information in the European Community ) Directive. Our model develops the Data Specification on Protected Sites , part of the INSPIRE Annex I. Hence its orientation towards georeferenced heritage data. The data model has been developed by an interdisciplinary group made up of specialists in the field of Geomatics and Cultural Heritage. It is our aim to achieve a generic, extendable and interoperable schema. It should be generic enough to embrace all kind of protected heritage data, from an ancient pilgrim’s way to the last artifact found in an archaeological excavation, extendable to allow any kind of data producer to adapt the model to the nature of their own information and interoperable to combine spatial data sets from different sources through network services, via Internet. The achievement of these three characteristics features international norms and standards referred to our kind of data. This implies adaptation to INSPIRE as well as to several ISO norms: ISO 19100 series regarding geographical information, ISO 21127 (CIDOC-CRM Model) for heritage thematic data and ISO 15836 (Dublin Core) for document resources. The data model comprehends two main dimensions: cultural entities in a strict sense, and the legislative figures created to protect them. This allows for the representation of cultural objects (i.e. historical buildings or archaeological sites) and their link to their legislative protection, keeping them as separate realities. In order to describe the data model, an international common language has been used: UML (Unified Modeling Language), a standard itself. Thus, we present a class-diagram depicting all legal and cultural entities, in the form of classes with their corresponding relations, attributes, constraints and stereotypes.Trabajo presentado en el 11th Spanish-Italian Symposium on Organic Chemistry SISOC-XI celebrado en San Sebastian (Espana), del 13 al 15 de julio de 2016.Trabajo presentado en el XVIII Congreso Peruano de Geologia, celebrado en Lima (Peru), del 16 al 19 de octubre de 2016Poster presentado en las XXXIII Jornadas de la Asociacion Espanola de Entomologia, celebradas en Almeria, del 15 al 18 de noviembre de 2017This research has been funded by the Spanish Ministry of Economy and Competitiveness, through research projects POSTFIRE (CGL2013-47862-C2-1-R) and GEOFIRE (CGL2012-38655-C04-01)The main contribution of this work is the improvement of the efficiency of a PEMFC power system while guaranteeing conditions that also improve its durability. Adopting the NMPC scheme with the distributed parameter model and the nonlinear observer, the efficiency of the PEMFC-based system can be maximized guaranteeing at the same time the appropriate internal gas concentration profiles to avoid global and local hydrogen and oxygen starvation and proper membrane humidification.Trabajo presentado en la 13a Reunion de la Red Espanola de Bacterias Lacticas (RedBAL), celebrada en Madrid (Espana) del 17 al 18 de junio de 2019Memoria de tesis doctoral presentada por Uxue Tilves Matheu para obtener el titulo de Doctora en Ciencias del Mar por la Universitat Politecnica de Catalunya (UPC), realizada bajo la direccion de la Dra. Ana Maria Sabates Freijo y de la Dra. Veronica Lorena Fuentes del Institut de Ciencies del Mar (ICM-CSIC).-- 149 pages, appendicesTrabajo presentado por Nuria Vallverdu Coll para la obtencion del grado de Master universitario en investigacion basica y aplicada en recursos cinegeticos, realizado en el Instituto de Investigacion en Recursos Cinegeticos (IREC, CSIC-UCLM-JCCM).Resumen del poster presentado a la 7th International Conference on Polyphenols and Health, celebrada en Tours (Francia) del 27 al 30 de octubre de 2015.Trabajo financiado con el Proyecto DR3AMCGL2014-55118 del MINECO (Proyecto coordinado del proyecto SALTACRES).Trabajo presentado en el Congreso Iberoamericano de Hidrogeno y Pilas de Combustible, celebrado en Barcelona (Espana) del 15 al 17 de octubre de 2014.El presente articulo describe el empleo del flujo de diseno basado en modelos para el desarrollo de bloques reconfigurables automaticamente para el procesado de imagenes sobre FPGA. Para ello se han concebido arquitecturas hardware que aprovechan caracteristicas especificas de algunos algoritmos de procesado y que pueden ser modificadas a traves de un novedoso procedimiento software. Este aspecto, unido a las restantes opciones de parametrizacion de los diferentes modulos, permite liberar al disenador de los detalles especificos de las implementaciones hardware asi como adaptar el consumo de recursos del FPGA a las necesidades de la aplicacion. El proceso de reconfiguracion automatica se ilustra con el bloque de convolucion generico realizando comparaciones entre implementaciones de diferentes arquitecturas sobre un FPGA Spartan-6 LX45.Trabajo presentado en el 8th European Meeting on Solar Chemistry and Photocatalysis, celebrado en Salonica (Grecia) del 25 al 28 de Junio de 2014.Resumen del poster presentado a las I Jornadas Cientificas del CIAL celebradas el 5 de junio de 2014 en Madrid.-- et al.Trabajo presentado en el 4th International Conodont Symposium, celebrado en Valencia (Espana), del 25 al 30 de junio de 2017Comunicacion presentada en el Aquaculture Europe 2014, celebrado en Donostia-San Sebastian, Espana, del 14 al 17 de octubre de 2014Triptico de la reunion celebrada en la Universidad de Murcia del 12 al 14 de Noviembre de 2015.Trabajo presentado en la 11a Reunion de la Red Espanola de Bacterias Lacticas (RedBAL), celebrada en Gijon (Asturias, Espana) del 28 al 30 de Junio de 2017Trabajo Fin de Master: Master en Catalisis Homogenea y Quimica Molecular. Grupo de Cristales liquidos y Polimeros, Departamento de Quimica Organica de la Universidad de Zaragoza (Curso 2014/2015).La elaboracion de este articulo se inscribe en el proyecto de investigacion “Innovacion oculta: cambio de paradigma en los estudios de innovacion” (FFI2011-25475), Ministerio de Economia y Competitividad, Gobierno de Espana.Poster presented at the 18th International Microscopy Congress (ICM 2014) that took place in Prague (Czech Republic) during 7-12th September 2014.Esta investigacion ha sido posible gracias a la financiacion de los proyectos del Plan Nacional CGL2012-36682 y CGL2016-75109-P del Ministerio de Economia y Competitividad, y al Convenio Principado de Asturias-Universidad de Oviedo y MNCN-CSIC.Resumen del poster presentado a la 10th International Conference one Carbon Metabolism, vitamins B and Homocysteine, celebrada en Nancy (Francia) del 7 al 11 de julio de 2015.La celulosa es la fuente de energia mas abundante que hay en la Tierra. Su transformacion en glucosa se considera la etapa mas importante en la produccion de biocombustibles a partir de biomasa lignocelulosica. Para esta transformacion es necesaria la accion sinergica de tres tipos de enzimas que hidrolizan los enlaces s-1,4 de la celulosa: (i) las endoglucanasas, que actuan al azar sobre enlaces internos, (ii) las celobiohidrolasas, que operan progresivamente por los extremos reductores y no reductores de la cadena, y (iii) las s-glucosidasas (BGL), que hidrolizan celobiosa y los celooligosacaridos mas pequenos hasta glucosa. Los hongos filamentosos son la principal fuente de celulasas, siendo los crudos del genero Trichoderma los mas estudiados y comercializados historicamente. Sin embargo, estos hongos secretan niveles insuficientes de BGL para una conversion efectiva de la celulosa, por lo que con frecuencia requieren ser suplementados con preparaciones ricas en esta enzima procedentes de otros hongos. Recientemente, se han descrito cepas de Penicillium con gran capacidad para secretar altos niveles de BGL al medio extracelular. Ademas de su papel en la hidrolisis de la celulosa las BGL tambien pueden emplearse para sintetizar compuestos de interes industrial mediante reacciones de transglicosilacion. En este trabajo se ha estudiado una nueva cepa fungica productora de celulasas, identificada como Talaromyces amestolkiae, en base a un analisis molecular y morfologico. Se han purificado a homogeneidad electroforetica tres BGL (BGL-1, BGL-2 y BGL-3) secretadas por el hongo y se han caracterizado bioquimicamente. BGL-1 y BGL-2 son proteinas monomericas, mientras que BGL-3 es un dimero funcional. Los valores de actividad maxima de estas enzimas se obtuvieron a pH 4,0 y entre 50-60 oC, siendo estables en un rango de pH de 4-7 y a 50 oC. Las tres mostraron distinto comportamiento en funcion del sustrato (pNPG o celobiosa), ensayandose tambien el efecto de determinados compuestos quimicos e inhibidores en su actividad. Las tres pueden hidrolizar celooligosacaridos de diferente longitud, disminuyendo la eficacia de hidrolisis con el aumento de la polimerizacion, y no son activas frente a polisacaridos. Ademas, mostraron actividad de transglicosilacion, formando alquilglicosidos y celooligosacaridos de mayor longitud que los usados como sustratos. Las tres BGL se identificaron mediante huella peptidica y en base la alta homologia con otras BGL fungicas relacionadas filogeneticamente, se disenaron cebadores especificos que permitieron la secuenciacion de los genes que codifican cada una de ellas. El analisis de las secuencias aminoacidicas mostro que BGL-1 es miembro de la familia 1 de las glicosil hidrolasas, mientras que BGL-2 y BGL-3 pertenecen a la familia 3. Teniendo en cuenta que existen pocas BGL fungicas cristalizadas, se construyeron modelos moleculares de estas ultimas en base a las estructuras con las que presentaron mayor identidad. El crudo enzimatico de T. amestolkiae, rico en BGL, se uso de forma individual y como suplemento de otros cocteles comerciales en experimentos de sacarificacion a partir de slurry acido de paja de trigo. Los resultados obtenidos indican que el hongo secreta, ademas de celulasas, otras enzimas complementarias que potencian la liberacion de azucares fermentables. Se analizo el secretoma de T. amestolkiae usando Avicel o slurry acido de paja de trigo como fuente de carbono. Las celulasas fueron las enzimas mas abundantes en ambas condiciones, sin embargo, en el crudo obtenido a partir de los cultivos en slurry aumento la proporcion de BGL y otras enzimas distintas a las celulasas, indicando que para la degradacion de un sustrato complejo es necesaria mayor diversidad enzimatica. Los resultados obtenidos en este trabajo abren nuevas vias para la formulacion de cocteles enzimaticos eficaces en el contexto de la degradacion de la biomasa lignocelulosica.Trabajo presentado en el 4th International Congress on Ichnology - ICHNIA 2016: Ichnology for the 21st century: (Palaeo) Biological Traces towards Sustainable Development, celebrado en Idanha-a-Nova (Portugal), del 6 al 9 de mayo de 2016Resumen del trabajo presentado al Joint European Magnetic Symposia (JEMS), celebrado en Glasgow (UK) del 21 al 26 de agosto de 2016.Vazquez, J. T. ... et. al.-- Inciativa Iberica para el Estudio de las Fallas Activas, Tercera Reunion Iberica sobre Fallas Activas y Paleosismologia IBERFAULT 2018 - Third Iberian Meeting on Active Faults and Paleoseismology, 11-13 June 2018, Alicante, Spain.-- 4 pages, 2 figuresLa infeccion temprana por Verticillium dahliae en olivar y la discriminacion entre niveles de severidad de la Verticilosis es viable mediante la utilizacion de imagenes termicas, multiespectrales e hiperespectrales adquiridas con vehiculos aereos no tripulados a escala de parcela o tripulados a escala de comarca. El indicador relacionado con la temperatura de copa (CWSI), indices de reflectancia (B, BG1, BR1) y la fluorescencia clorofilica (FLD3) se identifican como buenos indicadores para detectar la Verticilosis en etapas tempranas del desarrollo de la enfermedad, mientras que NDVI, PRI515, R/G, HI e indices de estimacion de clorofila y carotenos demuestran ser buenos indicadores para la cuantificacion de dano moderado o severo causada por Verticilosis, lo que puede ser de utilidad para el diseno de estrategias de control de la Verticilosis a escala de parcela y de comarca. La infeccion temprana por Verticillium dahliae en olivar y la discriminacion entre niveles de severidad de la Verticilosis es viable mediante la utilizacion de imagenes termicas, multiespectrales e hiperespectrales adquiridas con vehiculos aereos no tripulados a escala de parcela o tripulados a escala de comarca. El indicador relacionado con la temperatura de copa (CWSI), indices de reflectancia (B, BG1, BR1) y la fluorescencia clorofilica (FLD3) se identifican como buenos indicadores para detectar la Verticilosis en etapas tempranas del desarrollo de la enfermedad, mientras que NDVI, PRI515, R/G, HI e indices de estimacion de clorofila y carotenos demuestran ser buenos indicadores para la cuantificacion de dano moderado o severo causada por Verticilosis, lo que puede ser de utilidad para el diseno de estrategias de control de la Verticilosis a escala de parcela y de comarca. El olivo (Olea europaea L.) es el cultivo lenoso no tropical que ocupa mayor superficie en todo el mundo, con el 95% de la produccion mundial localizada en la cuenca mediterranea. Espana es el pais con mayor superficie de olivar del mundo con 2,6 MHa y aproximadamente el 39% de la produccion mundial. La Verticilosis, causada por el hongo de suelo Verticillium dahliae Kleb, constituye la principal amenaza para el olivar. Esta enfermedad afecta al olivo en todos los paises de tradicion olivarera y causa importantes perdidas de rendimiento y muerte de los arboles (Jimenez-Diaz y col., 2012). Este patogeno coloniza el sistema vascular de la planta, bloqueando el flujo del agua y finalmente induciendo estres hidrico (Van Alfen, 1989).Espana es el mayor productor de citricos de la Union Europea y el quinto a nivel mundial, con una produccion anual superior a cinco millones de toneladas (MAGRAMA, 2016). Este sector genera una gran cantidad de subproductos, con un elevado aporte energetico y alto contenido en pectinas y azucares, por lo que podrian usarse como materias primas en dietas para rumiantes. Sin embargo, los subproductos de citricos son muy diversos, por lo que su composicion quimica y valor nutritivo tambien puede ser variable (FEDNA, 2010; Feedipedia, 2016). El objetivo de este trabajo fue analizar la composicion quimica y la produccion de gas in vitro de subproductos de citricos producidos en nuestro pais.Resumen del trabajo presentado a las I Jornadas Cientificas del CIAL celebradas el 5 de junio de 2014 en Madrid.The Indian Summer Monsoon onset is one of the meteorological events most anticipated in the world. Due to its relevance for the population, the India Meteorological Department has dated the onset over the southern tip of the Indian Peninsula (Kerala) since 1901. The traditional method to date the onset was based in the judgment of skilled meteorologist and because of this, the method was considered subjective and not adequate for the study of long-term changes in the onset.Resumen del poster presentado a las I Jornadas Cientificas del CIAL celebradas el 5 de junio de 2014 en Madrid.Trabajo presentado en el European Workshop on Experimental and Behavioral Economics (EWEBE), organizado por la Universidad de Bologna los dias 26 y 27 de mayo de 2017 con el titulo: The impact of deliberative structures on voting behavio.--Trabajo presentado en los Bilkent Microeconomics Seminars organizados por la Bilkent University (Ankara, Turkey) el dia 29 de noviembre de 2017La compacidad del racimo es un rasgo de gran interes en la vid, dado que puede condicionar su calidad y rendimiento. Estos efectos se producen fundamentalmente a traves de su relacion, directa o indirecta, con la arquitectura del racimo, el comportamiento reproductivo y el grado o modo de exposicion de las bayas al ambiente. Respecto a los dos primeros, en un estudio previo, determinamos que tanto la longitud del raquis y sus primeras ramas como el numero de bayas por racimo son los caracteres con mayor incidencia en la compacidad entre los analizados. Ahora bien, el estudio de la base genetica responsable del numero de bayas requiere de su diseccion previa, dado que es una variable secundaria, resultado del numero de flores por inflorescencia y de la tasa de cuajado o conversion de flor en fruto. En este trabajo se presenta un estudio preliminar en el que se han caracterizado fenotipicamente 104 variedades de vid para estudiar su comportamiento reproductivo. Asi, sobre una base amplia de diversidad varietal, se han estimado variables como el numero de flores, la tasa de cuajado, corrimiento, millerandage, etc., evaluando su posible relacion con la compacidad del racimo. Este trabajo, una vez completado durante varios anos, permitira conocer la diversidad existente para el comportamiento reproductivo en la vid, asi como, de forma mas concreta, abordar la caracterizacion de los procesos geneticos responsables de las diferencias fenotipicas detectadas para el comportamiento reproductivo y sus elementos individuales y para la compacidad del racimo, identificando los posibles genes involucrados en dichos procesos.Trabajo presentado en la 11th International Conference on Grapevine Breeding and Genetics, celebrada en Pekin del 29 de julio al 2 de agosto de 2014.The Polarimetric and Helioseismic Imager (PHI) is the first deep-space solar spectropolarimeter, on-board the Solar Orbiter (SO) space mission. It faces: stringent requirements on science data accuracy, a dynamic environment, and severe limitations on telemetry volume. SO/PHI overcomes these restrictions through on-board instrument calibration and science data reduction, using dedicated firmware in FPGAs. This contribution analyses the accuracy of a data processing pipeline by comparing the results obtained with SO/PHI hardware to a reference from a ground computer. The results show that for the analysed pipeline the error introduced by the firmware implementation is well below the requirements of SO/PHI.This work has been financed within the framework of the projects P/309307 Arqueoastronomia of the IAC, and Orientatio ad sidera III (AYA2011-26759) of the Spanish MINECO. ACGG is Ramon y Cajal researcher of the MINECO.Este trabajo ha sido financiado por el proyecto RECUPERA 2020 del MINECO y EU-FEDER; y por el proyecto TRANS·FORMA (PP.TRA.TAA201600.9). La investigacion realizada por E. Rodriguez ha sido realizada gracias al programa DOC-INIA (INIA-FEDER).Trabajo presentado en el XXIV Congreso Iberoamericano de Catalisis (CICat 2014), “Catalisis para Biorrefineria”, celebrado en Medellin del 11 al 13 de septiembre de 2014.2 paginas y 1 tabla.- Trabajo presentado en el IX Congreso de Mejora Genetica de Plantas celebrado en Murcia entre el 18 y el 20 de septiembre de 2018.3 paginas, 1 tabla, 1 figura.--Trabajo presentado a las XVI Jornadas sobre Produccion Animal AIDA (Zaragoza, 19 al 20 de mayo, 2015).Poster presentado en el XVI International Clay Conference from the Oceans to Space Granada, Spain, July 17-21, (2017)XIII Reunion Iberica de Algas Toxicas y Biotoxinas Marinas (REDIBAL 2018) - XIII Reunion Iberica de Fitoplancton Toxico - XIII Iberian Toxic Algae and Marine Biotoxins Meeting, VI Simposio Internacional de Ciencias del Mar - VI International Symposium of Marine Sciences (ISMS 2018), 20- 22 June 2018, Vigo.-- 2 pagesThis research was financed with project AGL2011-22783 granted by the Spanish Ministry of Economy and Competiveness. M.C. Soto was supported by a CONACYT (Mexican Council of Sciences and Technology) doctoral fellowship.This work was supported by the Spanish Ministerio de Economia y Competitividad (grants CGL2012-36251 and CGL2015-64727-P to X.B., and BFU2010-15906 to JLM), and Catalan Government (2014 SGR 619). The research has also benefited from FEDER funds.Trabajo presentado en el IX International Symposium on Grapevine Physiology and Biotechnology, celebrado en La Serena (Chile) del 21 al 26 de abril de 2013.5 paginas, 4 figuras, 1 tabla.--Trabajo presentado a las: XLI Jornadas Cientificas y XVII Jornadas Internacionales de Ovinotecnia y Caprinotecnia. (Talavera de la Reina, Toledo, Espana, 14-16 septiembre, 2016).Se presenta una revisión histórica de los equinodermos Ordovícicos de Portugal. Todos los registros conocidos hasta el momento pertenecen al Ordovícico Medio-Superior (Darriwiliense-Katiense) y las asociaciones presentan gran diversidad aunque en general los taxones están poco o mal conocidos. La mayor parte de los yacimientos se concentran en las regiones de Amêndoa-Mação y Buçaco, aunque también existen citas de equinodermos en Arouca, Dornes, Moncorvo y Valongo. Por último se comentan futuras líneas de trabajo que ayudarán a comprender mejor estas faunas, perfeccionar y completar el conocimiento del registro fósil del grupo en el Ordovícico centroibérico. Ordovician echinoderms from Portugal: state of the artResumen del trabajo presentado al 37o Convegno Internazionale dei Docenti della Rappresentazione de la Unione Italiana Disegno (UDI), celebrado en Torino (Italia) del 17 al 19 de septiembre de 2015.Trabajo presentado al Danish Days on Caloric Materials and Devices, celebrado en Roskilde (Dinamarca) del 2 al 3 de octubre de 2017.Trabajo presentado en el ImageNano 2015 (Bringing together Nanoscience and Nanotechnology), celebrado en Bilbao del 10 al 13 de marzo de 2015.Este estudio ha sido financiado por el proyecto AGL-2012-40172-C02-01 del Ministerio de Economia y Competitividad (MINECO). AEF agradece al MINECO la financiacion de su contrato de investigacion (FPI).We present a detailed study of a X -ray selected sample of 5 submillimeter bright QSOs at

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P.A. Luning

Wageningen University and Research Centre

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