1,065 research outputs found

    Implantació ERP SAP R/3 a l'empresa Quimiwork

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    Implantació ERP SAP R/3 a una organització del sector químic.Implantación ERP SAP R/3 a una organización del sector químico

    A multi-parametric analysis of Trypanosoma cruzi infection: common pathophysiologic patterns beyond extreme heterogeneity of host responses

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    The extreme genetic diversity of the protozoan Trypanosoma cruzi has been proposed to be associated with the clinical outcomes of the disease it provokes: Chagas disease (CD). To address this question, we analysed the similarities and differences in the CD pathophysiogenesis caused by different parasite strains. Using syngeneic mice infected acutely or chronically with 6 distant parasite strains, we integrated simultaneously 66 parameters: parasite tropism (7 parameters), organ and immune responses (local and systemic; 57 parameters), and clinical presentations of CD (2 parameters). While the parasite genetic background consistently impacts most of these parameters, they remain highly variable, as observed in patients, impeding reliable one-dimensional association with phases, strains, and damage. However, multi-dimensional statistics overcame this extreme intra-group variability for each individual parameter and revealed some pathophysiological patterns that accurately allow defining (i) the infection phase, (ii) the infecting parasite strains, and (iii) organ damage type and intensity. Our results demonstrated a greater variability of clinical outcomes and host responses to T. cruzi infection than previously thought, while our multi-parametric analysis defined common pathophysiological patterns linked to clinical outcome of CD, conserved among the genetically diverse infecting strains

    El itinerario de aprendizaje con JUMP Math: un proceso cognitivo continuo desde 1º de primaria a 2º de secundaria

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    El aprendizaje de las matemáticas en nuestro país sigue presentando dos retos fundamentales: 1) Ofrecer un itinerario de aprendizaje cohesionado y progresivo a lo largo de los ciclos educativos, que evite el gran salto actual de Primaria a Secundaria; 2) Evitar que el alumnado se pierda en los primeros cursos de Primaria, cuando afrontan procesos de abstracción importantes, como el concepto y la operatoria de fracciones. En esta comunicación analizaremos el itinerario que propone JUMP Math, ajustado al proceso de maduración cognitiva, para abordar estos dos retos y permitir que los alumnos: 1) evolucionen de forma tranquila, manteniendo la motivación en todo momento por seguir aprendiendo; 2) conecten todos los bloques de aprendizaje de la propia disciplina; y 3) tengan puntos de retorno a contenidos y procesos competenciales para consolidar y profundizar su aprendizaje, y evitar que se pierdan en aspectos clave. Asimismo, detallaremos cómo este itinerario aborda el aprendizaje competencial, en torno a las ocho prácticas matemáticas que estiman esenciales los Estándares Estatales Comunes de Matemáticas, definidos en Estados Unidos tras años de investigación (desde 2002). Estas prácticas matemáticas implican el desarrollo de procesos y habilidades fundamentales para alcanzar un nivel avanzado

    Espai, context i creativitat : aprenentatge de les matemàtiques

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    L'ensenyament de les matemàtiques implica l'adquisició d'habilitats de planificació matemàtica i la capacitat d'identificar les matemàtiques en els contexts. En aquest sentit, l'Aprenentatge Basat en Projectes és una oportunitat perquè les matemàtiques recuperinaquest paper de motor. En aquest article es descriuen quatre propostes didàctiques al voltant de diverses temàtiques (superfícies i volums, construcció de formes geomètriques, Teorema de Thales, Estadística, Diagrames de Voronoi) en connexió amb diversos contextos del món real que fan rellevant el procés d'aprenentatge de les matemàtiques (disseny d'envasos, distribució de serveis municipals, efectes cinematogràfics, creació de formes artístiques). Es discuteix l'aportació d'aquest tipus d'activitats i es proporcionen orientacions per al seu desenvolupament.Mathematics learning implies the development of planning skills and the ability to identify mathematics in Contexts. Project-Based Learning is an opportunity to give to Mathematics this role as a driving force. In this article, we propose four Project-Based Learning activities in several Mathematic topics (Surfaces and volumes, construction of geometric shapes, Thales theorem, Statistics, Voronoi diagrams) in connection with real-world contexts (packaging design, distribution of municipal services, cinema effects, creation of artisticobjects). We discuss the didactic properties of this kind of activities and propose orientations for its development and application

    Genomic instability promoted by expression of human transposase-derived gene

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    DNA Transposases are enzymes that recognize and catalyze the movement of mobile elements in the human genome known as transposons. There are abundant transposase-derived genes in the human genome that have been conserved through evolution. Some of them, such as PGBD5, maintain their enzymatic activity in human cells. The expression of PGBD5 has been related to mobilization of DNA transposons through a motif specific cut and paste mechanism across the genome. The excision and insertion mechanism of transposable elements can cause genomic rearrangements and have a potential mutagenic activity in specific disease cases such as cancer. In this study, we analyze how the expression of PGBD5 leads to genomic instabilit

    Expression and characterization of the Trypanosoma cruzi dihydrofolate reductase domain

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    We have cloned and expressed in Escherichia coli a 702-base pair gene coding for the dihydrofolate reductase (DHFR) domain of the bifunctional dihydrofolate reductase-thymidylate synthase (DHFR-TS) from Trypanosoma cruzi. The DHFR domain was purified to homogeneity by methotrexate-Sepharose chromatography followed by an anion-exchange chromatography step in a mono Q column, and displayed a single 27-kDa band on SDS-PAGE. Gel filtration showed that the catalytic domain was expressed as a monomer. Kinetic parameters were similar to those reported for the wild-type bifunctional enzyme with Km values of 0.75 microM for dihydrofolate and 16 microM for NADPH and a kcat value of 16.5 s-1. T. cruzi DHFR is poorly inhibited by trimethoprim and pyrimethamine and the inhibition constants were always lower for the bifunctional enzyme. The binding of methotrexate was characteristic of a class of inhibitors that form an initial complex which isomerizes slowly to a tighter complex and are referred to as 'slow, tight-binding' inhibitors. While the slow-binding step of inhibition was apparently unaffected in the individually expressed DHFR domain, the overall inhibition constant was two-fold higher as a consequence of the superior inhibition constant value obtained for the initial inhibitory complex

    Assessing amphiphilic ABAB Zn(II) phthalocyanines with enhanced photosensitization abilities in in vitro photodynamic therapy studies against cancer

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    We have previously demonstrated that singlet oxygen photosensitization abilities of Zn(II) phthalocyanines (Zn(II)Pcs) are enhanced through α-functionalization with bulky fluorinated substituents (i.e., bis(trifluoromethyl)phenyl units) at facing positions of ABAB Zn(II)Pcs, where A and B refer to differently functionalized isoindoles. In this work, we have prepared the Zn(II)Pc ABAB 1 endowed with hydrophilic triethylene glycol monomethyl ether (i.e., at the A isoindoles) to provide solubility in aqueous media, together with its A3B and A4 counterparts, and compared their ability to behave as photosensitizers for photodynamic therapy. All photophysical data, aggregation studies and preliminary in vitro biological assays in cell cultures of SCC-13 (squamous cell carcinoma) and HeLa (cervical cancer cells), have proved ABAB 1 as the best photosensitizer of the seriesThis research was funded by MINECO, Spain (CTQ2017-85393-P and CTQ2016-78454-C2-1-R) , Instituto de Salud Carlos III and Feder Funds (FIS PI18/00708) and ERANET/MINECO EuroNanoMe

    Relative abundance and distribution of fisheries influence risk of seabird bycatch

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    Fisheries provide an abundant and predictable food source for many pelagic seabirds through discards, but also pose a major threat to them through bycatch, threatening their populations worldwide. The reform of the European Common Fisheries Policy (CFP), which intends to ban discards through the landing obligation of all catches, may force seabirds to seek alternative food sources, such as baited hooks from longlines, increasing bycatch rates. To test this hypothesis we performed a combined analysis of seabird-fishery interactions using as a model Scopoli's shearwaters Calonectris diomedea in the Mediterranean. Tracking data showed that the probability of shearwaters attending longliners increased exponentially with a decreasing density of trawlers. On-board observations and mortality events corroborated this result: the probability of birds attending longliners increased 4% per each trawler leaving the longliner proximity and bird mortality increased tenfold when trawlers were not operating. Therefore, the implementation of the landing obligation in EU waters will likely cause a substantial increase in bycatch rates in longliners, at least in the short-term, due to birds switching from trawlers to longliners. Thus the implementation of the landing obligation must be carefully monitored and counterbalanced with an urgent implementation of bycatch mitigation measures in the longline fleet

    Capture Myopathy in Little Bustards after Trapping and Marking

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    Four little bustards (Tetrax tetrax) (one adult and three juvenile males), captured with leg nooses and fitted with a backpack radiotag, died after capture. The first bird was found after 16 days with its left foot caught in the harness and died after 1 day. The other birds showed symptoms of capture myopathy after release, such as the difficulty or inability to fly and/or walk. They died after 5, 6, and 8 days, respectively. At necropsy, muscles affected in all cases were those from the legs, and these were diffusely pale and dull, with a soft friable texture. Microscopically these muscles had multiple foci of myofiber fragmentation, loss of striation, and necrosis; a mononuclear cell infiltrate was observed in muscle from two birds. These findings suggest the little bustard is susceptible to capture myopathy and that caution should be exercised during its capture and handling

    Enzyme bioprospection of marine-derived actinobacteria from the Chilean Coast and New Insight in the aechanism of keratin degradation in Streptomyces sp. G11C

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    Marine actinobacteria are viewed as a promising source of enzymes with potential technological applications. They contribute to the turnover of complex biopolymers, such as pectin, lignocellulose, chitin, and keratin, being able to secrete a wide variety of extracellular enzymes. Among these, keratinases are a valuable alternative for recycling keratin-rich waste, which is generated in large quantities by the poultry industry. In this work, we explored the biocatalytic potential of 75 marine-derived actinobacterial strains, focusing mainly on the search for keratinases. A major part of the strains secreted industrially important enzymes, such as proteases, lipases, cellulases, amylases, and keratinases. Among these, we identified two streptomycete strains that presented great potential for recycling keratin wastes—Streptomyces sp. CHA1 and Streptomyces sp. G11C. Substrate concentration, incubation temperature, and, to a lesser extent, inoculum size were found to be important parameters that influenced the production of keratinolytic enzymes in both strains. In addition, proteomic analysis of culture broths from Streptomyces sp. G11C on turkey feathers showed a high abundance and diversity of peptidases, belonging mainly to the serine and metallo-superfamilies. Two proteases from families S08 and M06 were highly expressed. These results contributed to elucidate the mechanism of keratin degradation mediated by streptomycetes
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