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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‣ A study of the geographic distribution of swamp forest in the coastal zone of the Araucanía Region, Chile

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
A study was made of the geographic distribution of swamp forest in the coastal territory of the Araucanía Region, Chile. An analysis of maps, aerial photographs, and satellite images was carried out, together with field work, to determine the location, degree of fragmentation, shape of fragments and habitat use of the forest. The results showed a total area of 7675 ha of forest (in a region of 165,168 ha) divided into 427 fragments of highly irregular shapes, set in a farming matrix. This forest type was located principally on alluvial (37%) and fluvial-marine (33%) plains associated with the Toltén and Queule river basins. Land unsuitable for agriculture accounted for 50% of the area of forest (CIREN Classes VII and VIII), while land with a superficial phreatic water table (0-20 cm depth) and poorly drained soils concentrated 47% and 66% of the forest respectively. The majority of the forested area stands on soils with poor drainage (available habitat), as a response to the greater biophysical restrictions which such areas represent for agriculture. Of the forested area, 59% was located on 859 properties belonging to small-holders with up to 200 ha, while 39% was located on 58 medium to large properties (over 200 ha and over 1000 ha respectively). Forty percent of the forest is within 300 m of a road and only 8% is more than 1000 m away. It is concluded that the forest is under severe pressure from human activity (by clearing for agricultural land...

‣ The Chilean elections of December 2009 and January 2010

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
On 13 December 2009, seven million Chileans went to the polls to elect the president who would run their country from 2010 to 2014, as well as lower chamber representatives of the country’s sixty electoral districts. The congressional election was characterized by continuity, with the center-left Concertación (CPD) and the center-right Alianza Por Chile (APC) confirmed as the two dominant congressional blocs. At the party level, the rightist Unión Demócrata Independiente (UDI) continued as the largest single party in electoral terms, while the Partido Demócrata Cristiano (PDC) continued its gradual but steady decline. The only novelty at the congressional level was the election of three congressional representatives from the Partido Comunista (PC), enabled by a pragmatic pact with the CPD to end its exclusion from the chamber. In terms of voter turnout and citizenship’s participation in elections, this electoral cycle was also characterized by continuity, with turnout reaching 84% of registered voters (close to the average for post-1990 elections), but with the percentage of the eligible population registered to vote dropping to an all-time low of 68%.

‣ ZigBee-based wireless sensor network localization for cattle monitoring in grazing fields

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
This paper presents the design of a localization scheme in wireless sensor networks (WSN) for cattle monitoring applications in grazing fields. No additional hardware was required for distance estimation since they were performed using the link quality indication (LQI), which is a standard feature of the ZigBee protocol. The ratiometric vector iteration (RVI) algorithm was implemented and modified to work with LQI measurements instead of the usual received signal strength indication (RSSI). Experimental results show acceptable localization performance given the requirements of usual cattle monitoring applications at low cost and low power consumption. © 2010 Elsevier B.V.

‣ Fish (Oncorhynchus mykiss) spermatozoa cryoprotectant-free vitrification: Stability of mitochondrion as criterion of effectiveness

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The aim of the present investigations was to test a novel technology comprising cryoprotectant-free vitrification of the spermatozoa of rainbow trout and to study the ability of sucrose and components of seminal plasma to protect these cells from cryoinjuries. Spermatozoa were isolated and vitrified using five different mediums: Group 1: standard buffer for fish spermatozoa, Cortland®-medium (CM, control); Group 2: CM+1% bovine serum albumin (BSA); Group 3: CM+1% BSA+0.125M sucrose; Group 4: CM+1% BSA+40% seminal plasma; and Group 5: CM+1% BSA+40% seminal plasma+0.125M sucrose. For cooling, 20μL suspensions of cells from each group were dropped directly into liquid nitrogen. For warming, the spheres containing the cells were quickly submerged in CM+1% BSA at 37°C with gentle agitation. The quality of spermatozoa before and after vitrification was analysed by the evaluation of motility, cytoplasmic membrane integrity (SYBR-14/propidium iodide staining technique), and mitochondrial membrane integrity (JC-1 staining). Motility (86%, 71%, 80%, 81%, and 82%, for Groups 1, 2, 3, 4, and 5, respectively) and cytoplasmic membrane integrity (90%, 82%, 83%, 84%, and 87%, respectively) of spermatozoa in all the 5 groups were not decreased significantly. All tested solutions can be used for vitrification of fish spermatozoa with good post-warming motility and cytoplasmic membrane integrity. However...

‣ Potential heterogeneity in crustacean zooplankton assemblages in southern chilean saline lakes

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The Chilean saline lakes are distributed mainly in the Atacama desert in northern Chile and the southern Patagonian plains. The scarce studies are restricted mainly to northern Chilean saline lakes, and these revealed that the main component in these ecosystems are the halophylic copepod Boeckella poopoensis Marsh 1906, or the brine shrimp Artemia franciscana (Kellog, 1906), and both species do not coexist. The present study consisted of field observations in zooplankton assemblages in southern Chilean saline lakes (51-53 °S). These first observations revealed three different patterns, one saline lake only with A. persimilis (Piccinelli and Prosdocimi, 1968), a second lake only with B. poopensis, and a third lake with A. persimilis, B. poopoensis and unidentified harpacticoid copepod. These results are different in comparison with the observations in the literature that described the non-coexistence between B. poopoensis with brine shrimps. Ecological and biogeographical topics were discussed.

‣ Species co-occurrences based on a presence/absence null model for Copepoda and cladocerans in Patagonia and Tierra del Fuego lakes and ponds

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The zooplankton assemblages in southern Chilean Patagonia are characterized by calanoid dominance and low species number that is observable under oligotrophic status and wide conductivity values, whereas at mesotrophic status the daphnids are dominant with high species number, and finally at hyper-saline environments halophilic species such as Artemia persimilis and/or the calanoid Boeckella poopensis predominate. In the present study data of different lakes and ponds between 45-53° S were analyzed, with the aim to determine potential structures at different sites. For this purpose a null model based in guild structure was applied, considering each guild a different kind of water body (lake, small lake, permanent pond, ephemeral pond, and saline lake). The results revealed in two simulations that guild are structured. These results are similar with other descriptions on the basis of null models that revealed a random pattern of species associations for similar ecosystems due to many species repeated in all or practically all studied sites or similarities of ecological features. Ecological and biogeographical topics were discussed. © 2010 Versita Warsaw and Springer-Verlag Wien.

‣ The construction of ethnic minority identity: A discursive psychological approach to ethnic self-definition in action

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The present article intends to examine how ethnic minority group members account for their ethnic identity as part of a series of interviews with young Mapuches on what it means to be Mapuche in contemporary Chilean society. The focus is on the actual accomplishment and display of ethnic self-definition and group identification. We draw on insights from discursive psychology to explore some features of common-sense practical reasoning that ethnic minority group members use to negotiate, self-ascribe or resist a particular sense of identity, and to produce observable and reportable identities. We have a particular interest in illustrating how ethnic self-definition can be seen as the contingent outcome of a practical and interpretive issue for members of society, with a special focus on how ethnic minority identity is constructed through the flexible use of group-defining attributes and characteristics, categories and common-sense categorial knowledge. We suggest that understanding the complex significance and meaning of ethnic self-definition for minority group members is dependent on engaging closely with its occasioned context of production and treating social identities as a feature of how people describe themselves. It is argued that this view of ethnic minority self-definition as a practical and interpretive issue and as a discursive product in action can provide a further contribution to literature of both discursive and intercultural studies of ethnic identification of minority groups...

‣ Effect of l-glutamate and glycine incorporated in activation media, on sperm motility and fertilization rate of rainbow trout (Oncorhynchus mykiss) spermatozoa

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
In terms of fish production, sperm activating substances are important in the controlled insemination. This holds also for salmonids, when being provided with an agent that energizes the spermatozoa. In this study two amino acids (l-glutamate and glycine) were evaluated in their effect on sperm motility and fertilizing capacity for rainbow trout (Oncorhynchus mykiss) spermatozoa. Different concentrations of l-glutamate and glycine were added to the sperm medium (T1=0.075-g per 100-ml of l-glutamate; T2=0.3-g per 100-ml of glycine; T3=0.075-g per 100-ml of l-glutamate-+-0.3-g per 100-ml of glycine). A control treatment was also performed without the two amino acids. Results show the capacity of l-glutamate to increase the time period of sperm motility (s) significantly in comparison to other treatments, registering a maximum motility time of 57.7±10.8-s. For fertilization issue, the results do not show significant differences, being the highest value for T1=98±4.5%. © 2010 Blackwell Verlag, Berlin.

‣ Assessment of wildlife use for ecotourism in the Rio Cruces wetlands, Ramsar site of Chile

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
Wildlife, excluding species of direct economic importance, is considered only when an appeal is obvious and demanded for ecotourism; however, methods for assessing fauna as a whole have not been implemented without a priori assumptions and biases belonging to rather intuitive management practices. A methodology for assessing wetland wildlife ecotourism objectives was developed. It was applied to a list of 50 birds and two mammals selected in the Cruces River wetlands, a Ramsar site in southern Chile. The ratings consider parameters that are demanded by ecotourism activities, such as abundance, aesthetic value, visibility, conservation status, endemism, historical/cultural or scientific value and importance of use, and taxonomic uniqueness. The visibility considered variables such as period of activity, colorfulness and mimicry, size, acoustic visibility, visibility of signs, behaviour, and degree of tolerance to observers. Each of these parameters was weighted according to their relative importance and values for each species were determined according to surveys in the field, literature review and expert panels.

‣ Social action as a culturally situated intersubjective project

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
In this article we analyze the concept of social action, rescuing some sociophenomenological and hermeneutic contributions that allow us to re-describe this concept and, through it, advance in the intercultural opening of the human sciences. Thus, we articulate the concepts of sense of the action (Schütz, 2003), and of experiential meaning (Taylor, 2005) to enhance the contextual-cultural conditions that constitute to all action and that allow their understanding. We propose to overcome the mechanistic analysis of any human action through re-description as a culturally situated intersubjective project, whose configuration allows us to understand that the actions of Others and Ours are expressions of a meaningful whole, which is always concrete and diverse.

‣ Diversity of small mammals in three environments of the National Reserve Lago Peñuelas, Región de Valparaíso, Chile

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
Chilean Mediterranean ecosystems, the only of this type present in South America of the four present in the world, are considered priority areas for conservation due to their high concentration of endemic species that have experienced accelerated rates of habitat destruction. They contain more than 39% of the mammal species, 47% of its endemic species, and 65% of the threatened species of Chile. Yet, these ecosystems are poorly represented in the system of protected areas, one of which is the Reserva Nacional Lago Peñuelas (RNLP) that is part of the Biosphere Reserve La Campana-Peñuelas, but whose mammal fauna is poorly documented. We studied both α and β diversity of the mammal assemblage in all three environments present at the RNLP (sclerophyllous forest, mixed shrub, and savanna of Acacia caven). Sherman traps grids were installed, pellets of two raptors (Tyto alba and Bubo magellanicus) were analyzed, tracks and signs were recorded, and direct observations were performed in the four seasons of the year 2001. We determined species richness (S), relative abundance, α diversity - considering its richness and structure (Shannon-Wiener and Pielou indexes)-, β diversity (Bray- Curtis index), and compared the diversity found with that documented for the same latitude from east to west. We recorded a total of 16 species: Thylamys elegans...

‣ An update of the distribution of Boeckella gracilis (Daday, 1902) (Crustacea, Copepoda) in the Araucania region (38°s), Chile, and a null model for understanding its species associations in its habitat

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The crustacean zooplankton of Chilean inland waters are characterized by abundant calanoid copepods, mainly from the genus Boeckella. The present study aims to update the distribution of Boeckella gracilis in the inland waters of the Araucania region (38-39°S) and to use null model analysis to understand the B. gracilis species associations. In the literature for Chile, this species is reported to be found in one northern lake and in three lakes of northern Patagonia. These findings are complemented by reports of this species for coastal and mountain ponds and mountain lakes of the Araucania region. These results agree with descriptions of this species for South American inland waters. The results of the null model analysis reveal factors regulating the species associations, whether comparing all the inhabitats or the guild structure, although some simulations show the opposite situation due to the presence of repeated species at many sites.; Los crustáceos zooplanctónicos en aguas continentales chilenas están caracterizados por la abundancia de copépodos calanoideos, principalmente del género Boeckella. El objetivo del presente trabajo es actualizar la distribución de esta especie en aguas continentales de la región de la Araucanía (38-39ºS)...

‣ Online portfolio of teacher training

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The purpose of the following study is to evaluate the degree of satisfaction with the online portfolio as a resource for assessing the initial teaching performance of students preparing at the Catholic University of Temuco, Chile, to become primary school teachers. Two groups were used in this research: an experimental one that worked with the online portfolio, and a control group that worked with the physical file. The sample consisted of 30 students randomly selected from the fourth year of the program. The level of satisfaction expressed by users of the portfolio was evaluated at the end of the practice-teaching experience. In order to take this measurement, an instrument called a semantic differential was especially designed for the purpose. The experimental group showed a difference significantly greater than that of the control group in the variable degree of satisfaction with the portfolio tool. Also, a positive and significant correlation was observed between the degree of satisfaction expressed by the students, and the score obtained by them in the initial-teaching-performance portfolio.

‣ Membranoproliferative glomerulonephritis possibly associated with over-vaccination in a cocker spaniel

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
Membranoproliferative glomerulonephritis was observed in a seven-month-old male cocker spaniel dog. The clinical, microbiological, biochemical, radiographic and ultrasonographic examinations ruled out neoplasia, congenital disease and infectious disease. The anamnesis revealed that the owner had vaccinated the dog seven times, one vaccination per month, without veterinarian supervision. In both kidneys, severe thickening of the glomerular capillary walls was observed. Electron microscope examination revealed a large number of electron-dense deposits that were primarily in the glomerular subendothelial spaces and the basal membrane, which is compatible with antigen-antibody complexes. The immunohistochemical examination revealed that the antigen present in the glomeruli corresponded with the antigen present in the vaccine. We report a type III hypersensitivity nephropathy in a young dog, which was possibly caused by over-vaccination. © 2010 British Small Animal Veterinary Association.

‣ Karyotype study in Luzuriaga radicans (Liliales: Luzuriagaceae)

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The karyotype of Luzuriaga radicans R. & P. was quantitatively studied, assessing characters such as chromosome morphology and size, satellite location, asymmetry level and bimodality. L. radicans has an asymmetric and bimodal karyotype 2n = 20 with three metacentric pairs, followed by six submetacentric and one subtelocentric chromosome pair. One satellite was observed in the short arm of chromosome pair 6. The total haploid set length was 48.7 μm and the mean chromosome size was 4.87 ± 2.35 μm. Comparing L. radicans with other two species of the genus a high resemblance among their karyotypes was found. © 2010 Versita Warsaw and Springer-Verlag Wien.

‣ Modernity, city and subject. Approaches from the myth of the primordial father

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The present article deals with three categories that emerge as a result of the deep social changes that have occurred since the consolidation of the modern western world: modernity, city and subject. The analysis takes up the Freudian Myth of Primary Father and upholds the thesis that modernity signifies a form of death of the father embodied in the figure of the absolute monarch, initiating the concept of social ties understood as State.

‣ Effect of EPA/DHA ratios on the growth and survival of Galaxias maculatus (Jenyns, 1842) larvae reared under different salinity regimes

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
Despite the importance of certain highly unsaturated fatty acids in osmotic regulation, few studies have been addressed to determine the essential fatty acid requirements for a given species cultured under different salinities. As Galaxias maculatus is a diadromic species, the present study aimed to determine the effect of salinity on the optimum dietary EPA/docosahexaenoic (DHA) ratio for survival and growth during the larval stages. Larvae were fed for 20 days with rotifers containing two different EPA/DHA ratios (low: 0.64 and high: 2.18) at three different salinities (0, 10 and 15 g L-1). The results of this study showed a marked effect of water salinity on larval dietary lipid utilization in G. maculatus larvae. These results suggested that G. maculatus larvae reared at higher salinities may have a higher dietary requirement for DHA, whereas larvae reared at 0‰ showed higher requirements for EPA. The overall results of the present study indicate that even small changes in salinity can determine the optimum dietary EPA/DHA ratio and the quantitative essential fatty requirements of fish. This may have important repercussions and affect the rearing performance of G. maculatus cultured under different salinities. © 2010 The Authors. Journal Compilation © 2010 Blackwell Publishing Ltd.

‣ The genus Artemia leach, 1819 (Crustacea: Branchiopoda). I. True and false taxonomical descriptions

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The brine shrimp Artemia is important for aquaculture since it is highly nutritious. It is also used widely in biological studies because it is easy to culture. The aim of the present study is to review the literature on the taxonomical nomenclature of Artemia. The present study indicates the existence of seven species: three living in the Americas, one in Europe, and three in Asia.

‣ Amphipoda and Decapoda as potential bioindicators of water quality in an urban stream (38°S, Temuco, Chile)

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The benthic crustaceans in Chilean rivers and streams are characterized by their marked endemism and low species number. Ecological studies have indicated that some species may be used as indicators of water quality, considering the involvement of river basins in human agricultural, industrial, and urban activities. The aim of the present study was to study the abundance of benthic crustaceans in a small stream located inside Temuco town, and to determine correlations of their various abundances with pH, temperature, and dissolved oxygen. The species discussed here are Aegla rostrata, Hyalella araucana, and Parastacus pugnax. We report an inverse correlation between dissolved oxygen and A. rostrata abundance, as well as of temperature with H. araucana abundance, whereas P. pugnax showed no significant correlations. The ecological results are discussed. © Koninklijke Brill NV, Leiden, 2010.

‣ Centrifugal settling of flocculated suspensions: A sensitivity analysis of parametric model functions

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
Português
The centrifugal settling of a flocculated suspension in a rotating tube can be modeled by a strongly degenerate parabolic partial differential equation whose coefficients depend on two material-specific model functions, namely, the hindered settling function and the effective solid stress function. These model functions are usually given by certain nonlinear algebraic expressions that involve a small number of parameters. The present work is related to the problem of determining these parameters for a given material. This problem of parameter identification consists in minimizing the distance between observed and simulated concentration profiles by successively varying the parameters employed for the simulation, starting from an initial guess. The feasibility and robustness of this procedure, which does not necessarily lead to a unique solution, decisively depends on the sensitivity of the solution of the direct problem to the different scalar parameters. These sensitivities are evaluated by a series of numerical experiments. It turns out that the model is extremely sensitive to the choice of the so-called critical concentration marking the transition between hindered settling and compression. Moreover, the robustness of the parameter identification method depends significantly on whether intermediate (i.e....