70 research outputs found

    Global value chains and inward foreign direct investment in the 2000s

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    This work is a preliminary study on the relation between the degree of participation of countries in GVCs and their FDI inward stocks and many questions remain unanswered. For instance, what are the drivers and determinants of location of cross-border activities via investment in GVCs? Is FDI more volatile with GVCs? How do choices about location vary according to the particular parts of the value chain that TNCs choose to locate outside their home countries? What are the prospects for further evolution of GVCs and their role in global investment? How functions the empirical relation between GVCs and FDI assuming, for its part, FDI as a GVC driver? What policies should policymakers adopt to increase GVC participation and FDI-related? A fruitful avenue for further research is ahead.info:eu-repo/semantics/publishedVersio

    Evaluation of different methods for efficient extraction of hemicelluloses leaves and tops of sugarcane

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    There are around 9 million tons of sugarcane crop residue per year in Colombia that are not recovered but they have potential to make value-added products. It is necessary to know the residue components, especially those from hemicellulose, to clarify the type of process to obtain the hemicellulose monosaccharides and isolate them efficiently. In order to separate pure hemicelluloses, five processes of extraction from tops and leaves of CC 8592, CC 8475, and V 7151 sugarcane varieties were studied. After evaluating exposure to dewaxing using ethanol and chloroform-methanol mixtures, residues were subjected to different concentrations of hydrogen peroxide and acidified sodium chlorite to achieve delignification. Additionally, procedures of extraction were developed with sodium hydroxide, potassium hydroxide, and precipitation. Chloroform-methanol dewaxing and sodium chlorite with sodium borohydride delignification allowed to achieve the highest extraction yield, with hemicellulose recovery ranging from 0.20-0.34 g hemicellulose/g dry residue in the varieties studied.En Colombia se producen alrededor de 9 millones de toneladas de residuos de la cosecha de la caña de azúcar por hectárea cada año, que no han sido valorizados hacia ningún tipo de producto. Es necesario conocer su composición, en especial el contenido de hemicelulosas, para dilucidar el proceso para obtener los monosacáridos de éstas y aislarlos eficientemente. Para separar las hemicelulosas puras, se estudiaron cinco procesos de extracción a partir de las hojas y cogollos de las variedades de caña de azúcar CC 8592, CC 8475 y V 7151. Después de evaluar la eliminación de ceras con etanol y mezclas de cloroformo-metanol, los residuos se expusieron a diferentes concentraciones de peróxido de hidrógeno y clorito de sodio acidificado para lograr su deslignificación. Adicionalmente, se desarrollaron procedimientos de extracción con hidróxido de sodio e hidróxido de potasio, y de precipitación. El método que logró el mayor rendimiento fue el de desceración con metanol-cloroformo y deslignificación con clorito de sodio y borohidruro de sodio, con un rango de recuperación entre 0.20-0.34 g hemicelulosas /g residuo seco en las variedades estudiadas

    Parámetros fisicoquímicos para la síntesis de ácido láctico ó etanol de la bacteria (corynebacterium glutamicum)

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    El interés por obtener productos para la industria de biocombustibles a partir de desechos agrícolas, conduce a las investigaciones en la búsqueda de sistemas microbianos resistentes y costo-efectivos. La Corynebacterium glutamicum, es un microorganismo usado para producir amino-ácidos, crece en gran variedad de sustratos y es resistente durante la fermentación, a variaciones en el pH, temperatura, presión osmótica y acumulación de alcohol, características que lo hacen candidato a ser mejorado para la síntesis de ácido láctico y etanol. Aún se desconocen aspectos de su fisiología que aumenten su eficiencia en convertir azúcares (C5 y C6) en estos dos metabolitos. Por tanto, este trabajo se basó en estudiar e identificar los parámetros fisicoquímicos que tuvieron un mayor efecto sobre el crecimiento bacteriano y la síntesis de ácido láctico. Para lograr este objetivo, ocho variables fueron evaluadas en un modelo estadístico producido en erlenmeyer, con estos resultados se hallaron las condiciones óptimas que fueron evaluadas en un cultivo por lotes en biorreactor. La temperatura, la concentración de biotina y azúcar fueron las variables con mayor impacto (p and lt; 0,05) sobre el cultivo. Usando las condiciones óptimas, 36 °C; 6,1 mg/L de biotina y 50 g/L de glucosa, se obtuvo una max de 0,394 h-1, 16 g/L de ácido láctico a las 15 h del proceso con un rendimiento del 32%; observándose un mayor consumo de sustrato durante el crecimiento y poca disponibilidad para la fermentación, que sugiriendo una alimentación del cultivo al final de la fase exponencial que aumente los rendimientos de producción

    Comunica-Media: Uso de la grabación de clases, el screencast y la videoconferencia en el aula

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    A medida que la tecnología mejora y se extiende entre los usuarios es conveniente y necesario que los sistemas educativos se adapten y aprovechen lo que estas nuevas tecnologías pueden ofrecer. Así se puede motivar más a los alumnos y profesores ofreciéndoles contenidos más completos e interactivos. En esta comunicación se presenta el proyecto Comunica-Media del Servicio de Innovación Educativa de la Universidad Politécnica de Madrid (UPM). El objetivo principal de este proyecto es promover y evaluar el uso de la grabación de clases, la videoconferencia y el screencast en seis diferentes escuelas y asignaturas de la UPM

    Genetic Structure of the Spanish Population

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    <p>Abstract</p> <p>Background</p> <p>Genetic admixture is a common caveat for genetic association analysis. Therefore, it is important to characterize the genetic structure of the population under study to control for this kind of potential bias.</p> <p>Results</p> <p>In this study we have sampled over 800 unrelated individuals from the population of Spain, and have genotyped them with a genome-wide coverage. We have carried out linkage disequilibrium, haplotype, population structure and copy-number variation (CNV) analyses, and have compared these estimates of the Spanish population with existing data from similar efforts.</p> <p>Conclusions</p> <p>In general, the Spanish population is similar to the Western and Northern Europeans, but has a more diverse haplotypic structure. Moreover, the Spanish population is also largely homogeneous within itself, although patterns of micro-structure may be able to predict locations of origin from distant regions. Finally, we also present the first characterization of a CNV map of the Spanish population. These results and original data are made available to the scientific community.</p

    Array-CGH in patients with Kabuki-like phenotype: Identification of two patients with complex rearrangements including 2q37 deletions and no other recurrent aberration

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    Background: Kabuki syndrome (KS) is a multiple congenital anomaly syndrome characterized by specific facial features, mild to moderate mental retardation, postnatal growth delay, skeletal abnormalities, and unusual dermatoglyphic patterns with prominent fingertip pads. A 3.5 Mb duplication at 8p23.1-p22 was once reported as a specific alteration in KS but has not been confirmed in other patients. The molecular basis of KS remains unknown. Methods: We have studied 16 Spanish patients with a clinical diagnosis of KS or KS-like to search for genomic imbalances using genome-wide array technologies. All putative rearrangements were confirmed by FISH, microsatellite markers and/or MLPA assays, which also determined whether the imbalance was de novo or inherited. Results: No duplication at 8p23.1-p22 was observed in our patients. We detected complex rearrangements involving 2q in two patients with Kabuki-like features: 1) a de novo inverted duplication of 11 Mb with a 4.5 Mb terminal deletion, and 2) a de novo 7.2 Mb-terminal deletion in a patient with an additional de novo 0.5 Mb interstitial deletion in 16p. Additional copy number variations (CNV), either inherited or reported in normal controls, were identified and interpreted as polymorphic variants. No specific CNV was significantly increased in the KS group. Conclusion: Our results further confirmed that genomic duplications of 8p23 region are not a common cause of KS and failed to detect other recurrent rearrangement causing this disorder. The detection of two patients with 2q37 deletions suggests that there is a phenotypic overlap between the two conditions, and screening this region in the Kabuki-like patients should be considered.This work was funded by grants from the Spanish Ministry of Health (FIS PI042063), Genome Spain and the European Commission (FP6-2005-037627). IC was supported by a Juan de la Cierva Postdoctoral fellowship
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