Últimos itens adicionados do Acervo: Universidade Católica de Temuco

A Universidade Católica de Temuco é uma institução privada confessional do Chile, fundada pelo bispo Alejandro Menchaca Lira em 1959.

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‣ Cultivo larvario del puye (Galaxias maculatus), en un sistema cerrado de recirculación

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
Este estudio muestra los antecedentes del cultivo larvario del puye, Galaxias maculatus (Jenyns), un pequeño pez de aguas frías del hemisferio sur. Para el cultivo, larvas recién eclosionadas fueron puestas en estanques de 500 litros de volumen útil. Las larvas fueron alimentadas utilizando una secuencia de rotíferos, Arfemia spp. y alimento inerte. Durante todo el sistema de producción que duró 150 días, fue necesario realizar un desdoble y una separación por tamaño. Los resultados muestran que esta especie puede alcanzar su tamaño comercial (4 a 6 cm) en seis meses aproximadamente, si es cultivado en un sistema intensivo como el propuesto. Los resultados muestran que las larvas de Galaxias maculatus, responden satisfactoriamente a la secuencia de alimentación que incluye rotiferos, Arfemia spp. y alimento inerte, en un sistema intensivo de producción como el estudiado.; This study reports data on the larval culture of the "puye", Galaxies maculatus (Jenyns), a small cold water fish occurring in the Southern Hemisphere. For this culture, recently enclosed larvae were placed into 500 liter tanks and fed first with rotifers, then with Artemia spp., and finally with prepared feed. Over the growth period of 150 days, several separations of the fishes were necessary based on size differentials. Results suggested this species would reach a commercial size of 4 to 6 cm in about six months using the intensive system proposed. The larvae of this fish responded well to the feeding sequence described...

‣ Seminario internacional. Bases para la piscicultura del puye Galaxias spp

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Libro
Português
Proyecto FONDEF D96I1071 "Investigación y desarrollo de la tecnología para el cultivo comercial del puye Galaxias maculatus"; Galaxias maculatus es una especie circumantártica de importancia comercial que se encuentra en Chile, Argentina, Islas Malvinas, Nueva Zelandia, Tasmania y Australia. El estado juvenil cristalino que se consume se le conoce comúnmente como puye, angula o whitebait. Esta delicatessen es un símil de la angula del género Anguilla, que corresponde a la larva cristalina leptocephala. El puye o whitebait es tradicionalmente consumido en Chile y Nueva Zelanda alcanzando altos precios. El estudio de mercado muestra interesantes posibilidades en los países donde ya se consume, en los países donde se consume la angula, tales como México, Perú, sur hispano de USA, España o en los países de oriente donde consumen larvas de peces cristalinos, como Japón y China. Las pesquerías de puyes en Chile se encuentran sobrexplotadas, motivo por el cual las capturas anuales son bajas y fluctúan entre 10 a 20 toneladas. En Nueva Zelanda, extraoficialmente se menciona una captura de 300 toneladas anuales, que son insuficientes para la demanda interna y deben importar un símil de origen chino. El desarrollo de la tecnología de cultivo del puye Galavias maculatus es fundamental para una producción masiva que permita sustentar la exportación. Así mismo...

‣ Effects of different diets on the survival and growth of puye (Galaxias Maculatus)

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
Galaxias maculatus (Puye or angula) is an estuarian and lacustrine fish that lives in cold water of the southern hemisphere. It is a particularly appreciated as a glass-eel substitute and its price is between US$ 28-100Kg.

‣ Effects of rumen fluid pre-incubation on in vitro proteolytic activity of enzymatic extracts from rumen microorganisms

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
Enzymatic extracts were prepared from rumen fluid (RF) either directly after collection or after incubation in enriched media and their proteolytic activities were measured and compared. The objective of RF in vitro cultivation was to augment enzymatic activity by using diverse incubation media containing different feed substrates to selectively induce microorganisms, with essentially unrestricted sources of energy and N. The effects on protein degradation in bovine serum albumin (BSA) and soybean meal, rapeseed meal, dehydrated alfalfa meal and perennial ryegrass were determined. Enzymatic extracts were characterized by means of protease zymograms. Two adult Holstein Friesian rumen fistulated cows were used as RF donors. Standard anaerobic incubation techniques in buffer-mineral media were used, and protein degradation was measured as residual true protein after enzymatic incubations. Results reveal an effect of RF pre-incubation on protein degradation (P<0.0001) measured in BSA and in feed substrates, and also on the hydrolysis rate (P<0.001), measured with native substrates only. The enzymatic extracts showed a high potential for proteolytic degradation, reaching 785 mg/g crude protein (CP) degraded in BSA after 12 h of incubation...

‣ Financial evaluation of management in secondary forests of canelo (Drimys winteri) in the coastal range of Valdivia, Chile

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
Young secondary forests of Drimys winteri have excellent growth and regeneration, and cover an area of 230,000 hectares in Chile. However, there is no supply of high-value timber to feed the growing market opportunities. The objective of this study was to evaluate the profitability of thinning trials in secondary forests of Drymis winteri in a medium-productivity site. The thinning treatments were considered late thinning, and were named as moderate thinning (E1), heavy (E2) and heavy (E3), in addition to a control treatment (E4). The yield was determined using the net present value (NPV), land expected value (LEV), and modified internal rate of return (MIRR), incorporating discount rates of 6 %, 8 % and 10 % and low administration costs in two scenarios, no costs before thinning (S1) and costs since the establishment of the stand (S2). The results for the NPV and VPS in S2 were negative, in contrast with S1, which doubled its profitability compared with the control treatment. The E2 treatment had the highest profitability in the S1 case, with a NPV of USD 2,724 ha-1, a VPS of USD 3,771 for a 6 % rate, and a MIRR of 19 %. For an operational level the moderate thinning treatment (E1) is desirable since it reduces the risk of windfall...

‣ Serotypes of listeria monocytogenes isolated on food produced in cautin province, Chile

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
It has been reported in Chile that L. monocytogenes is present in differents kind of foods. The aim of this study was to obtain information of the occurrence of the bacteria in sausages, raw milk and vegetables produced in Cautín Province, and to know the L. monocytogenes serotypes involved. For this purpose sausages, raw milk and several vegetables samples, were collected on 2003. For the isolation and identification of L. monocytogenes, the samples were grown in tripticase soy broth (TSB) inoculated into a preenrichment broth for Listeria (35°C followed by an inoculation on selectives medias Oxford and Palcam (35-37°C). Biochemical test were performed to all the typical Listeria colonies according to the methodology recommended by Bacteriological Analytical Manual (FDA). Serotyping was carried out using commercial specific antisera on 53 bacterial strains. Results of the analysis indicated the presence of L. monocytogenes in 61.1% of sausages samples, 0.0% in raw milk samples and in 16.6% of vegetables samples. These results could indicate failure in the hygiene practices, like cleaning and sanitizing the surface in contact with the food. The presence of serotipe 4e in 3 strains were found in some sausages. There was a strain of virulent serotype 1/2a...

‣ Isolation and characterisation of pectic substances from murta (Ugni molinae Turcz) fruits

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
Cell walls polysaccharides from murta fruit (Ugni molinae Turcz), an endemic Chilean species with relevant food uses, were fractionated by water, ammonium oxalate, hot diluted HCl and cold diluted NaOH extractions. The polysaccharide fractions were analysed for monosaccharide composition and physicochemical properties. Pectic substances were found in all extracts, but mainly in the oxalate and acid soluble fractions, in which they appear as homogalacturonan polymers. Murta pectin was further extracted by hot diluted acid treatment using industrial conditions, yielding 30% by weight of dry fruit. The polymer showed similar composition and physicochemical properties to those of commercial citrus pectin, presenting a galacturonic acid content of 70.9% (w/w), a molecular weight of 597. kDa, and a methoxylation degree of 57%. The FT-IR spectrum of murta pectin suggests the presence of ferulic acid residues on its structure and the NMR analysis confirmed the structure of this polysaccharide. It is concluded that murta fruit can be considered as a valuable source of high quality pectin. © 2010 Elsevier Ltd.

‣ Nine judges enter into dialogue with nine hypotheses about the proof of facts in criminal cases

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
This article formulates nine hypotheses concerning the proof of facts in criminal proceedings, which are analysed by nine judges of Chilean criminal Courts (Tribunal de Juicio Oral y de Garantía). Seven hypotheses aimed at describing different practices that take place in the courts and two of them concern how judges should act in certain hard cases. The matters are grouped in the following categories: a) scopes of the compromise that judges should have in order to operate with true stories as support of their decisions; b) difficulties that arise as consequence of the epistemic weakness of the evidence available in trials and the possible slants in their interpretation; c) requirements of the evaluation of the proof according to the sana crítica; and d) meaning that should have the standard of proof beyond reasonable doubt. In this way, a dialogue between the system of beliefs of judges and of jurists takes place.

‣ Productive characterization of milk farms using multivariate analysis

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The objective of this study was to characterize dairy productive systems of Vilcún commune, Cautín province, the IXth Region, Chile, linking qualitative and quantitative variables using statistical multivariate analysis of simple correspondence. 24 dairy farms were analyzed: 11 considered small size, 7 medium ones and 6 big dairy producers. The general results show that the big producers have a larger surface of hectares dedicated to the dairy, more days of lactation and an average production of 14 L per day, in comparison with 9 L of the medium and small producers. The multivariable analysis of simple correspondence shows association between the educational level of the dairy producers and the quantity of produced milk. Thus, big producers have possess a professional title of degree senior technician or engineer. On the other hand, the level of education of the milkers was at least secondary level for the big producers and basic complete and incomplete for the small and medium producers. Likewise, the producers who carry out twice-daily milking have bigger total production of milk, and the drying therapy is carried out more in big and medium producers than in the small ones. The use of cooling tank is of permanent use in the producers with a greater productive volume. Finally...

‣ Digestibilidad aparente de los ensilajes de residuos pesqueros en tilapias rojas (Oreochromis mossambicus x O. niloticus)

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
Mediante un diseño completamente aleatorizado con tres repeticiones, se determinó la digestibilidad in vivo de nutrientes y energía de los ensilajes de residuos pesqueros en tilapias rojas (Oreochromis mossambicus x O. niloticus). El ensilaje químico se preparo con ácido sulfúrico 98% (20 ml/kg) y ácido fórmico (10 ml/kg) y el ensilaje biológico con miel de caña (150 g/kg) y yogurt (Lactobacilus bulgaris y streptococcus acidophilus; 30 g/kg). Se usó oxido crómico como indicador y las heces se recolectaron por un sifón desde el fondo de los tanques. Se obtuvo que la digestibilidad aparente de algunos nutrientes difirió en función del tipo de ensilaje, entre tanto la proteína digestible fue mayor para el ensilaje químico y la materia seca, calcio y fósforo para el ensilaje biológico. Digestibilidades iguales (P>0,05) se presentó para los lípidos, cenizas y energía. Concluyendo que los ensilajes de residuos pesqueros presentan alto valor nutricional, lo que constituyen una fuente de proteína alternativa en la formulación de raciones para tilapias rojas.; By means of a design completely randomized with three repetitions, in vivo digestibility of nutrients and energy in fishing waste silages were determined for red tilapia (Oreochromis mossambicus x O. niloticus). Chemical silage prepared with sulphuric acid 98% (20 ml/kg) and formic acid (10 ml/kg) and the biological with sugar cane molasses (150 g/kg) and of yogurt (Lactobacilus bulgaris and streptococcus acidophilus; 30 g/kg). The chromic oxide was used as inert indicator and fecal sample were recollected by siphon from the bottom of tanks. As a result...

‣ Photosynthetic and leaf anatomical characteristics of Castanea sativa: A comparison between in vitro and nursery plants

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The anatomic and functional leaf characteristics related to photosynthetic performance of Castanea sativa growing in vitro and in nursery were compared. The irradiance saturated photosynthesis in in vitro grown plantlets was significantly lower compared to nursery plants (65 vs. 722 μmol m)

‣ Contenido de adn nuclear en el congrio colorado Genypterus chilensis (Guichenot, 1881) (Actinopterygii: Ophidiidae)

Fonte: Universidad de Concepción, Facultad de Ciencias Naturales y Oceanográficas. Publicador: Universidad de Concepción, Facultad de Ciencias Naturales y Oceanográficas.
Tipo: Artículo de Revista
Português
Los estudios sobre contenido de ADN nuclear en el género Genypterus son escasos, y el presente trabajo entrega por primera vez la estimación del contenido de ADN nuclear de Genypterus chilensis con un valor 2C = 1,0 + 0,06 pg, valor cercano al descrito para otras especies de Ophidiidae que varían entre 1,2 y 1,68 pg.; Studies about nuclear DNA content in the genus Genypterus are scarce, and the present study gives the first estimate of nuclear DNA content of Genypterus chilensis, with a value of 2C= 1.0 + 0.06 pg, value close to that obtained for other Ophidiidae species wich range between 1.2 and 1.68 pg.

‣ Abolición y persistencia de la esclavitud indígena en Chile colonial: estrategias esclavistas en la frontera araucano-mapuche

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
La esclavitud legal de los araucano-mapuches del sur de Chile capturados en la guerra constituyó una de las excepciones al estatuto jurídico de vasallos del rey reconocido a los indígenas de América a partir de 1542. Nuestro trabajo consiste en una reflexión sobre la esclavitud y otras formas de dependencia y trabajo forzado. Consideraremos prácticas ilegales de esclavitud que abonaron el terreno para su legalización a partir de 1608, recalcando el carácter precario, movedizo y contradictorio de la legislación hasta que se inicia el proceso de abolición definitiva de la esclavitud en 1674. Quisiéramos entender, gracias a los fragmentos de historias de vida que ha sido posible rescatar, cómo los españoles de Chile intentaron perpetuar la esclavitud de hecho, cuando la esclavitud de derecho dejó de ser posible. Finalmente examinaremos cómo, más de un siglo después, ciertos destinos de mujeres y niños, rayan con prácticas esclavistas.; For the araucano-mapuche Indians of southern Chile captured in battle during warfare, a system of legal slavery became one of the exceptions to the juridical statute for the vassals of the King extended to include the Indian population of America since 1542. Our work consists on a reflection on slavery and other forms of dependency and forceful work. Synthetically...

‣ Abolición y persistencia de la esclavitud indígena en Chile colonial: estrategias esclavistas en la frontera araucano-mapuche

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
La esclavitud legal de los araucano-mapuches del sur de Chile capturados en la guerra constituyó una de las excepciones al estatuto jurídico de vasallos del rey reconocido a los indígenas de América a partir de 1542. Nuestro trabajo consiste en una reflexión sobre la esclavitud y otras formas de dependencia y trabajo forzado. Consideraremos prácticas ilegales de esclavitud que abonaron el terreno para su legalización a partir de 1608, recalcando el carácter precario, movedizo y contradictorio de la legislación hasta que se inicia el proceso de abolición definitiva de la esclavitud en 1674. Quisiéramos entender, gracias a los fragmentos de historias de vida que ha sido posible rescatar, cómo los españoles de Chile intentaron perpetuar la esclavitud de hecho, cuando la esclavitud de derecho dejó de ser posible. Finalmente examinaremos cómo, más de un siglo después, ciertos destinos de mujeres y niños, rayan con prácticas esclavistas.; For the araucano-mapuche Indians of southern Chile captured in battle during warfare, a system of legal slavery became one of the exceptions to the juridical statute for the vassals of the King extended to include the Indian population of America since 1542. Our work consists on a reflection on slavery and other forms of dependency and forceful work. Synthetically...

‣ Las políticas públicas como práctica de contrainsurgencia social

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
Este artículo plantea que las políticas públicas constituyen una práctica de contrainsurgencia social, por cuanto los mecanismos de definición, implementación y seguimiento a las políticas en pocos casos se orientan a promover la organización social y la participación activa de los beneficiarios; por el contrario, los órganos y actores del poder hegemónico a través de ellas ejercen un control sobre las organizaciones y las personas destinatarios/ as de estas. Nuestro planteamiento se sustenta en el análisis hermenéutico de los discursos de un grupo de dirigentes sociales del sector Pedro de Valdivia, de la comuna de Temuco (Chile), con los cuales se inicia un proceso de investigación iniciado el año 2008, en conjunto con un grupo de estudiantes de séptimo semestre de la Carrera de Trabajo Social, que permitiera un reconocimiento mutuo, para la posterior inserción de prácticas profesionales. Los aportes desarrollados por Gramsci sobre Hegemonía y Bloque Histórico, nos permite fundamentar el análisis, interpretación y comprensión de los discursos de estos dirigentes sociales; This article states that public policies constitute a social counterinsurgency practice, because the mechanisms of definition, application and follow-up on the policies are oriented only in few cases to promoting the social organization and active participation of the beneficiaries; on the contrary...

‣ Convergence analysis of a vertex-centered finite volume scheme for a copper heap leaching model

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
In this paper a two-dimensional solute transport model is considered to simulate the leaching of copper ore tailing using sulfuric acid as the leaching agent. The mathematical model consists in a system of differential equations: two diffusion–convection-reaction equations with Neumann boundary conditions, and one ordinary differential equation. The numerical scheme consists in a combination of finite volume and finite element methods. A Godunov scheme is used for the convection term and an P1-FEM for the diffusion term. The convergence analysis is based on standard compactness results in L2. Some numerical examples illustrate the effectiveness of the scheme.

‣ A null model to explain zooplankton species associations in saline lakes of the south american altiplano (14-27 degrees S).

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Português
La diversidad del zooplankton en lagos salinos poco profundos de Sudamérica es baja y su distribución depende altamente de la salinidad, la cual varía de moderada a alta. A salinidades menores a 90 g/l predomina el copépodo halofílico Boeckella poopoensis (Marsh, 1906), mientras que a salinidades superiores a ese nivel, el anostraco Artemia franciscana (Kellogg, 1912) es el componente exclusivo de los hábitats. Esto constituye sin embargo una información parcial. En una revisión de la literatura disponible para lagos salinos Andinos en Bolivia, Chile y Perú se confirma que la presencia y distribución de ambas especies está significativamente regulada por el nivel de la salinidad. Los resultados del modelo nulo de co-ocurrencia de especies indican que las asociaciones de especies no son aleatorias, y estos resultados están respaldados por el análisis de correlación, el cual indica una relación inversa significativa entre número de especies con salinidad, y hubo relaciones directas significativas entre número de especies con la superficie del hábitat. El bajo número de especies que es característico de estos hábitats y su dependencia con los cambios de salinidad efectuado por las condiciones climáticas provee un buen modelo de sistema de monitoreo de cambios climáticos.; Zooplankton diversity in shallow salt lakes of the Andean countries in South America is low and distribution is highly dependent on salinity...

‣ Effects of diet type and metabolizable energy intake on tympanic temperature of steers fed during summer and winter seasons

Fonte: American Society of Animal Science Publicador: American Society of Animal Science
Tipo: Artículo de Revista
Português
A summer study and a winter study were conducted using an incomplete factorial structure in a complete randomized design. Within season, the factors studied were 1) type of diet, which included 2 levels of ME, classified as either concentrate (3.04 Mcal of ME/kg) or roughage (2.63 Mcal of ME/kg) diets, and 2) daily ME intakes (MEI) of 11, 18, and 25 Mcal of ME/d for the roughage diets and 18, 25, and 32 Mcal of ME/d for the concentrate diets. In Exp. 1 (summer study), 30 steers (5 steers/treatment combination) were used to collect tympanic temperatures (TT). In Exp. 2 (winter study), 24 steers (4 steers/treatment combination) were used to collect TT. Mean TT was 0.3°C greater for summer than winter (38.9 vs. 38.6°C, respectively; P < 0.05). Steers fed diets based on concentrate tended to display greater TT than steers fed diets based on roughage. Season × diet × hour interactions were found for TT (P = 0.01). In the winter, greater TT (P < 0.05) were found from 0900 to 1400 h when an equal amount of MEI was derived from a concentrate-based vs. roughage-based diet. In cattle fed roughage-based diets during the summer, TT = 38.63 + 0.0114∙MEI, whereas for cattle fed concentrate-based diets, TT = 38.69 + 0.0114∙MEI. During the winter...

‣ Numerical Approximation of Oscillatory Solutions of Hyperbolic-Elliptic Systems of Conservation Laws by Multiresolution Schemes

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The generic structure of solutions of initial value problems of hyperbolic- elliptic systems, also called mixed systems, of conservation laws is not yet fully understood. One reason for the absence of a core well-posedness theory for these equations is the sensitivity of their solutions to the structure of a parabolic regularization when attempting to single out an admissible solution by the vanishing viscosity approach. There is, however, theoretical and numerical evidence for the appearance of solutions that exhibit persistent oscillations, so-called oscillatory waves, which are (in general, measure-valued) solutions that emerge from Riemann data or slightly perturbed constant data chosen from the interior of the elliptic region. To capture these solutions, usually a fine computational grid is required. In this work, a version of the multiresolution method applied to a WENO scheme for systems of conservation laws is proposed as a simulation tool for the efficient computation of solutions of oscillatory wave type. The hyperbolic-elliptic 2×2 systems of conservation laws considered are a prototype system for three-phase flow in porous media and a system modeling the separation of a heavy-buoyant bidisperse suspension. In the latter case...

‣ A fully adaptive numerical approximation for a two-dimensional epidemic model with nonlinear cross-diffusion

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
An epidemic model is formulated by a reaction-diffusion system where the spatial pattern formation is driven by crossdiffusion. Whereas the reaction terms describe the local dynamics of susceptible and infected species, the diffusion terms account for the spatial distribution dynamics. For both self-diffusion and cross-diffusion nonlinear constitutive assumptions are suggested. To simulate the pattern formation two finite volume formulations are proposed, which employ a conservative and a non-conservative discretization, respectively. An efficient simulation is obtained by a fully adaptive multiresolution strategy. Numerical examples illustrate the impact of the cross-diffusion on the pattern formation.