364 research outputs found

    Maturidade sexual de Chilabothrus angulifer (Serpentes: Boidae) em estado selvagem

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    El majá de Santa María (C. angulifer) es el único boido en Cuba. Es el mayor miembro del género, así como el mayor ofidio del Caribe Insular (> 400 cm de longitud hocico-cloaca), esto la convierte en una especie icónica de la herpetofauna cubana. A pesar de que su historia natural se conoce muy poco, varios estudios describen aspectos de su biología reproductiva en cautiverio. Aquí documentamos las edades y tallas con que ambos sexos alcanzan la madurez sexual en la naturaleza y mostramos que el majá de Santa María alcanza la adultez con una talla mucho más pequeña de lo que previamente se ha reportado para especímenes de cautiverio. Basados en la escasa información sobre la tasa de crecimiento de C. angulifer en la naturaleza, los machos deben alcanzar la talla adulta después de los 3 años y las hembras después de los 5 añosA jiboia-cubana, Chilabothrus angulifer, é o único boídeo de Cuba. É a maior serpente do gênero e também das Índias Ocidentais (comprimento rostro-cloacal > 400 cm); por essa razão, trata-se de uma espécie icônica da herpetofauna cubana. Apesar de sua história natural ser pouco-conhecida, diversos estudos descrevem aspectos de sua biologia reprodutiva em cativeiro. Documentamos aqui o tamanho e a idade em que ambos os sexos atingem a maturidade sexual na natureza e mostramos que essa serpente atinge a idade adulta com um tamanho muito menor do que previamente relatado para indivíduos cativos. Com base na informação limitada sobre a taxa de crescimento de C. angulifer na natureza, os machos atingem o tamanho reprodutivo após 3 anos, e as fêmeas, após 5 anosThe Cuban Boa (C. angulifer) is the only boid snake in Cuba. It is the largest member of the genus, as well as the largest snake in the West Indies (> 400 cm in snout-vent length); as such, it is an iconic species of the Cuban herpetofauna. Although the snake’s natural history is poorly known, several studies describe aspects of its reproductive biology in captivity. Herein we document the sizes and ages at which both sexes reach sexual maturity in nature, and show that the Cuban Boa reaches adulthood at a much smaller size than previously reported for captive snakes. Based on the limited information on the growth rate of C. angulifer in nature, males must reach breeding size after 3 years and females after 5 year

    Enzimska ekstrakcija hidroksicinamičnih kiselina iz otpada nastalog pri proizvodnji kave

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    Ferulic, caffeic, p-coumaric and chlorogenic acids are classified as hydroxycinnamic acids, presenting anticarcinogenic, anti-inflammatory and antioxidant properties. In this work, enzymatic extraction has been studied in order to extract high value-added products like hydroxycinnamic acids from coffee pulp. A commercial pectinase and enzyme extract produced by Rhizomucor pusillus strain 23aIV in solid-state fermentation using olive oil or coffee pulp (CP) as an inducer of the feruloyl esterase activity were evaluated separately and mixed. The total content (covalently linked and free) of ferulic, caffeic, p-coumaric and chlorogenic acids was 5276 mg per kg of coffee pulp. Distribution was as follows (in %): chlorogenic acid 58.7, caffeic acid 37.6, ferulic acid 2.1 and p-coumaric acid 1.5. Most of the hydroxycinnamic acids were covalently bound to the cell wall (in %): p-coumaric acid 97.2, caffeic acid 94.4, chlorogenic acid 76.9 and ferulic acid 73.4. The content of covalently linked hydroxycinnamic acid was used to calculate the enzyme extraction yield. The maximum carbon dioxide rate for the solid-state fermentation using olive oil as an inducer was higher and it was reached in a short cultivation time. Nevertheless, the feruloyl esterase (FAE) activity (units per mg of protein) obtained in the fermentation using CP as an inducer was 31.8 % higher in comparison with that obtained in the fermentation using olive oil as the inducer. To our knowledge, this is the first report indicating the composition of both esterified and free ferulic, caffeic, p-coumaric and chlorogenic acids in coffee pulp. The highest yield of extraction of hydroxycinnamic acids was obtained by mixing the produced enzyme extract using coffee pulp as an inducer and a commercial pectinase. Extraction yields were as follows (in %): chlorogenic acid 54.4, ferulic acid 19.8, p-coumaric acid 7.2 and caffeic acid 2.3. An important increase in the added value of coffee pulp was mainly due to the extraction of chlorogenic acid.Ferulinska, kafeinska, p-kumarinska i klorogena kiselina pripadaju u hidroksicinamične kiseline, koje imaju antikarcinogena, protuupalna i antioksidativna svojstva. U radu je ispitana enzimska ekstrakcija hidroksicinamičnih kiselina iz otpada nastalog pri proizvodnji kave. Upotrijebljene su, zasebno i u smjesi, komercijalna pektinaza te enzimski esktrakt dobiven fermentacijom na čvrstoj podlozi od maslinovog ulja ili otpada nastalog pri proizvodnji kave (da bi se potaknula aktivnost feruloil esteraze), s pomoću Rhizomucor pusillus 23aIV. Ukupni je udio kovalentno vezanih i slobodnih hidroksicinamičnih kiselina bio 5276 mg/kg otpada. Od toga je bilo: 58,7 % klorogene; 37,6 % kafeinske; 2,1 % ferulinske i 1,5 % p-kumarinske kiseline. Većina je hidroksicinamičnih kiselina bila kovalentno vezana za staničnu stijenku, i to: 97,2 % p-kumarinske; 94,4 % kafeinske; 76,9 % klorogene i 73,4 % ferulinske kiseline. Pomoću udjela kovalentno vezanih hidroksicinamičnih kiselina izračunat je prinos ekstrahiranog enzima. Maksimalni je udio fermentacijom proizvedenog CO2 postignut na čvrstoj podlozi od maslinovog ulja, i to za kraće vrijeme nego na podlozi od otpada nastalog pri proizvodnje kave, iako je feruloil esteraza proizvedena primjenom ove druge podloge pokazala aktivnost veću za 31,8 %. Prema spoznajama autora ovo je prvo istraživanje u kojem su određeni udjeli vezanih i slobodnih hidroksicinamičnih kiselina u otpadu nastalom pri proizvodnji kave. Najveći je prinos ekstrakcije hidroksicinamičnih kiselina postignut primjenom komercijalne pektinaze i enzimskog ekstrakta. Pritom je izdvojeno 54,4 % klorogene; 19,8 % ferulinske; 7,2 % p-kumarinske i 2,3 % kafeinske kiseline, pa je zaključeno da je ovaj postupak dobar za ekstrakciju klorogene kiseline

    Can Our Fingers Alone Raise Us Up to the Sky? Analysis of the Digit Ratio Association with Success in Olympic Wrestling

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    The aim of this study is to analyse the contribution of the second to fourth digit ratio (2D:4D) to success in wrestling. A total of 180 elite wrestlers who participated in the 2011 Spanish Wrestling Championship took part in this study (132 men, 23.6±6.1 years old; 48 women, 21.7±4.9 years old). Prior to competition, wrestlers were interviewed about their years of training experience and their hands were scanned. 2D:4D was calculated using computer-assisted image analysis. A multinomial logistic regression coefficient to calculate odd ratios (OR’s) and 95% confidence intervals (CI’s) were established to determine the contribution of digit ratio and training experience to success in Olympic wrestling. Additionally, mean and median analyses were calculated between males and females, and between successful and non-successful wrestlers in order to establish differences in 2D:4D and training experience between these groups. There were no differences between successful and non-successful wrestlers in 2D:4D (p=0.87 for right hand, and p=0.46 for left hand), whereas having high training experience supposed an increase up to 4.38 (1.70 – 11.01) times more likely to be successful. Our results suggest that 2D:4D fails in predicting wrestling success, whereas training background is a good predictor of competition prowess in highly trained wrestlers

    Valorización de Volcan Compañía Minera S.A.A. y subsidiarias (2016)

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    El objetivo de este trabajo es presentar los resultados de la valorización económica que se ha realizado a Volcan Compañía Minera S.A.A. y subsidiarias, en adelante “Volcan” o la “Compañía” al cierre del ejercicio 2016, empresa dedicada a la extracción, producción y comercialización de minerales como plata y concentrados de zinc y plomo con operaciones mineras en la sierra central del Perú. Dentro de la presente valorización se efectuaron tres metodologías: i) Flujo de caja descontado (FCD), ii) Múltiplos comparables y iii) Valor contable de la empresa. Volcan, en el año 2016 se encontró dentro del ranking mundial como la quinta empresa productora de zinc, octava de plata y novena de plomo. Para efectuar la valorización se tomó información histórica de los estados financieros trimestrales consolidados y anuales auditados al cierre de los ejercicios 2013 al 2016, memorias anuales y reportes de sostenibilidad. Se consultaron también diversas fuentes de información, tales como documentos emitidos por la Compañía a través de su página web, bases de datos financieras como Bloomberg y Reuters e información pública disponible en la Superintendencia de Mercados y Valores (SMV) y la Bolsa de Valores de Lima (BVL)

    Strong photoluminescence and sensing performance of nanosized Ca0.8Ln0.1Na0.1WO4 (Ln = Sm,Eu) compounds obtained by the dry "top-down" grinding method

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    Two lanthanide doped nanosystems Ca0.8Ln0.1Na0.1WO4 (Ln=Eu, Sm), denoted as Eu@CWO and Sm@CWO, were prepared by a “top-down” approach in three simple steps which included activation, miniaturization by high-energy milling, and further calcination. The solids were thoroughly characterized by X-ray powder diffraction (XRPD), Raman spectroscopy and scanning-electron microscopy (SEM). Also, analyses of the compounds’ structure and the impact of the milling on crystallite shape and size were carried out through Rietveld refinements. The solid-state photoluminescence was studied in terms of excitation, emission, lifetimes (obs) and europium-quantum yields. Finally, the Eu@CWO sample was employed as potential water-stable chemical sensor towards toxic cations, finding a quenching effect in the presence of iron ionsFil: Gomez, Germán Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Pérez López, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Ayscue III, Russell Lee. University Of Georgetown; Estados UnidosFil: Knope, Karah E.. University Of Georgetown; Estados UnidosFil: Torres Deluigi, María del Rosario. Universidad Nacional de San Luis; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Narda, Griselda Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; Argentin

    Ceniza de bagazo de caña como aditivo al cemento portland para la fabricación de elementos de construcción

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    La industria azucarera genera anualmente enormes cantidades de residuos. Entre estos se encuentra la denominada ceniza de bagazo de caña (CBC) que resulta de la combustión de este subproducto y cuya dispersión en el ambiente contamina el aire y afecta la salud humana. En el Valle del Cauca hay trece ingenios que satisfacen la demanda nacional de azúcar, pero no mitigan la problemática ambiental asociada con sus residuos, por lo se hace necesario buscar alternativas. En varios estudios se ha demostrado que la CBC presenta un elevado contenido de sílice (SiO2) y alúmina (Al2O3), que le dan una buena actividad puzolánica como sustituto parcial del cemento portland y constituye una valiosa alternativa que representa un doble beneficio, por un lado, valoriza un desecho y por otro, contribuye a la reducción de gases de efecto invernadero liberados durante la manufactura de cemento (0.85-1 kg CO2/kg cemento). Esta es una propuesta interesante, si se considera la enorme proporción de contaminación generada por la industria cementera, que según datos del International Cement Review, su producción mundial para el 2010 alcanzó los 3.3 mil millones de toneladas (Intercement, 2010). En el presente estudio se evaluó el uso de la CBC como reemplazo parcial del cemento Portland para la elaboración de elementos de construcción

    Patrimonio geopaleontológico de los depósitos aluviales situados sobre la terraza +28 m del Jarama. Nuevos datos micropaleontológicos y cronológicos (Solar de la Real Fábrica de Paños de San Fernando de Henares)

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    Trabajo presentado en la Reunión de Arqueología Madrileña, celebrada en Alcalá de Henares el 20 y 21 de noviembre de 2014.[ES] Durante los trabajos de vigilancia de los movimientos de tierras asociados a la obra de la construcción de viviendas en el solar de la Real Fábrica de Paños (en adelante RFP) de San Fernando de Henares se documentaron materiales geológicos de edad miocena y cuaternaria con un contacto lateral dinámico entre ellos, constituido por una falla extensional de dirección norte-sur. En los niveles cuaternarios se registraron numerosos restos paleontológicos y algunas piezas de industria lítica. Según los estudios preliminares geomorfológicos y de macromamíferos (Tapias y Arango 2008; Yravedra et al. 2008; Dones et al. 2011) se asignó una cronología genérica de Pleistoceno Medio, confirmada por la datación obtenida por racemización de aminoácidos de un molar de Equus caballus (304 ka). En este trabajo se aportan nuevos datos a partir de la revisión y estudio de los restos de micromamíferos recuperados en la unidad 3. La presencia de Microtus brecciensis y M. arvalis en la base de los depósitos aluviales posibilita su adscripción cronológica al Pleistoceno Medio avanzado (MIS 8 o MIS 6).[EN] During the monitoring of the movements of land associated with the work of the construction of homes in the Solar of the Royal Factory of Cloths of San Fernando de Henares, some geological materials of Miocene and Quaternary age were documented. Numerous paleontological remains and some stone tools have been registered in these quaternary levels. According to geomorphological preliminary studies and macromammals (Tapias y Arango 2008; Yravedra et al. 2008; Dones et al. 2011) a generic Middle Pleistocene chronology was assigned. This was confirmed by the aminoacids racemization dating of Equus caballus molar (304 ka) This paper provides new data of the remains of micromammals recovered. The faunal assemblage, with Microtus brecciensis and M arvalis found at the base of the alluvial deposits, has allowed reviewing previous studies. It could be more specific on the geochronological and paleoenviromental contextualization of remains and materials that could be assigned to advanced Middle Pleistocene (MIS 8 or MIS 6).Peer reviewe

    SMOS REFLEX 2003: L-band emissivity characterization of vineyards

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    The goal of the Soil Moisture and Ocean Salinity mission over land is to infer surface soil moisture from multiangular L-band radiometric measurements. As the canopy affects the microwave emission of land, it is necessary to characterize different vegetation layers. This paper presents the Reference Pixel L-Band Experiment (REFLEX), carried out in June-July 2003 at the Vale/spl grave/ncia Anchor Station, Spain, to study the effects of grapevines on the soil emission and on the soil moisture retrieval. A wide range of soil moisture (SM), from saturated to completely dry soil, was measured with the Universitat Polite/spl grave/cnica de Catalunya's L-band Automatic Radiometer (LAURA). Concurrently with the radiometric measurements, the gravimetric soil moisture, temperature, and roughness were measured, and the vines were fully characterized. The opacity and albedo of the vineyard have been estimated and found to be independent on the polarization. The /spl tau--//spl omega/ model has been used to retrieve the SM and the vegetation parameters, obtaining a good accuracy for incidence angles up to 55/spl deg/. Algorithms with a three-parameter optimization (SM, albedo albedo, and opacity) exhibit a better performance than those with one-parameter optimization (SM).Peer Reviewe
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