Nunes-Nesi A.,Federal University of Viçosa |
Brito D.S.,Federal University of Viçosa |
Inostroza-Blancheteau C.,Catholic University of Temuco |
Fernie A.R.,Max Planck Institute of Molecular Plant Physiology |
Araujo W.L.,Federal University of Viçosa
Trends in Plant Science | Year: 2014
The majority of soils in tropical and subtropical regions are acidic, rendering the soil a major limitation to plant growth and food production in many developing countries. High concentrations of soluble aluminum cations, particularly Al3+, are largely responsible for reducing root elongation and disrupting nutrient and water uptake. Two mechanisms, namely, the exclusion mechanism and tolerance mechanism, have been proposed to govern Al3+ resistance in plants. Both mechanisms are related to mitochondrial activity as well as to mitochondrial metabolism and organic acid transport. Here, we review the considerable progress that has been made towards developing an understanding of the physiological role of mitochondria in the aluminum response and discuss the potential for using this knowledge in next-generation engineering. © 2013 Elsevier Ltd.
Parra S. D.,Catholic University of Temuco
Revista Medica de Chile | Year: 2013
This article aims to analyze, from a legal perspective, the boundaries of the obligation imposed on health care providers to inform the patient. This requirement originated and was developed as an ethical issue. However, with the newly approved law regulating the rights and duties of patients, the obligation to inform can be viewed from prisms and principles that differ from those governing medical ethics. With this purpose, we will focus on the comparative experience, which will allow us to evaluate the responsibility of health care providers when this duty is breached. We will try to answer the following questions: Which medical information must be informed to the patient? When should the doctor inform the patient? In which form should this information be provided?
Levano M.,Catholic University of Temuco
Communications in Computer and Information Science | Year: 2015
This work develops data interpretation by elastic nets based on statistical mechanics, for the detection of clusters of data structures in an n-dimensional space. The problem is to find patterns of activity in genes of E. coli, which are stressed by different carbon sources that allow them to activate various expressiveness. The results of the study show that for a string node using distinct temperatures distinct phase transitions are shown. As result of phase transitions, changed centroids of respective groupings are observed. At each node, different behaviors revealed by carbon sources applied to genes are observed. © Springer International Publishing Switzerland 2015.
Jara-Seguel P.,Catholic University of Temuco |
Urrutia J.,University of Concepción
Revista Chilena de Historia Natural | Year: 2012
Cytogenetic data on Chilean angiosperms have been reported since at least eight decades ago; however, much of this information is disperse in diverse sources and is not readily available as a comprehensive document that allows having a general vision on advances and gaps in this matter. The goal of this paper is to summarize the advances and prospets on cytogenetic studies of the Chilean angiosperms based on compiled publications from 1929 to 2010. We found 78 publications supplied by four groups of Chilean researchers and some foreign specialists. Cytogenetic data have been reported for 139 Chilean angiosperm species (2.8 % of the total), which belong to 58 genera and 34 families. During 2001-2010 there was an increase in the number of publications, being available 40 reports including 95 additional species. Based on these data, we hope that such a trend can be maintained in the next decade if the current research groups and young specialists continue to be interested in the study of native plants. © Sociedad de Biología de Chile.
Ortloff A.,Catholic University of Temuco |
Pena P.,Catholic University of Temuco |
Riquelme M.,Catholic University of Temuco
Forensic Science International | Year: 2012
Knowledge regarding the succession patterns of insects that visit carcasses as well as the other arthropod that colonise them and analysis of the parameters that are associated with larvae allow calculation of the minimum postmortem interval (PMI). This information is obtained from experiments carried out under specific geoclimatic conditions, which determine their application in forensic environments under similar conditions. The field study presented here is the first in Chile to analyse the decomposition process of pig carcasses and the associated succession of insects, colonising species and parameters related to larval masses. All of the larvae obtained from daily samples were measured (in mm), and their mean, range, standard deviation and stage of development (instars) were determined. The carcasses reached the dry remains stage in only 11 days. Seven species of Diptera visited the carcass during the process, but only two species colonised it by means of egg deposition followed by development of larvae: Cochliomyia macellaria (Fabricius) and Lucilia sericata (Meigen) (Diptera: Calliphoridae), which exhibited a duration of the development cycle from egg to adult of 21 days. The collected Coleoptera correspond to five predator species (Staphilinidae and Histeridae). From the results of this study, it can be concluded that only some of the insect species present in this region can provide information that can be used in forensic entomology and that analysis of larval masses of colonising species can be a valuable tool for determining the PMImin in this region of Chile. © 2012 Elsevier Ireland Ltd.
de los Rios P.,Catholic University of Temuco |
Roa G.,Catholic University of Temuco
Zoologia | Year: 2010
Even though the Chilean lakes are characterized by their oligotrophy, a transition from oligotrophy to mesotrophy, due human intervention, has been reported in some lakes. Nevertheless, there are still some pristine and unpolluted small lakes and ponds in mountain zones, free of human intervention and surrounded by native forests. Nine unpolluted, oligotrophic and pristine water bodies located in Cañi Park, a mountain zone with altitudes between 1000 to 1500 m a.s.l and forests where Nothofagus dombeyi, N. pumilio and Araucaria araucana predominate, were studied. For each sampled lake, zooplankton was collected and environmental parameters were obtained (conductivity, total dissolved solids, and chlorophyll concentration). A null model of species co-occurrence was applied to determine randomness in species associations. All sites revealed low species richness (< 6); the calanoid copepod Boeckella gracilis Daday, 1902 was present in all sites. The results of the null model indicated randomness or absence of regulatory factors in species associations. Only few species occur in practically all localities. Also, a significant inverse association between chlorophyll concentration with percentage of calanoid copepods and a weak direct association between chlorophyll concentration and percentages of cladocerans were found. © 2010 Sociedade Brasileira de Zoologia.
Parodi J.,Catholic University of Temuco
Systems Biology in Reproductive Medicine | Year: 2014
Sperm cells are complicated in vitro models. Their viability is limited, and physiology is complex. The study of their properties is of great application in the animal production as viable and functional gametes are essential. It has been shown that the decrease of sperm cell viability parallels an increase of the reactive oxygen species (ROS). Reactive oxygen species is secondary to normal metabolic processes of the cell-like flagellar movement. There is evidence of strategies that reduce ROS levels by using exogenous or endogenous antioxidants with the intention that seminal plasma protects the sperm cells and increases viability. Perhaps viability can increase by reducing that flagellar movement which is regulated by calcium. The phenomenon has not been fully characterized, but it is established that in certain mammalian models, the entrance of calcium via specific channels such as CATsper or voltage-dependent channels, signals flagellar movement. Previous reports have indicated that a change in the concentration of calcium or if the temperature is altered, the function of mammal sperm cells is reduced or blocked and viability prolonged. Fish sperm can remain immobile for several weeks but when activated the number of mobile and viable sperm is reduced at a faster rate. However, if the cells are not mobilized the semen can be preserved for longer periods. As presented in this paper, this supports the notion that by modulating calcium channels to reduce motility the viability of these cells can increase. © 2014 Informa Healthcare USA, Inc.
De Los Rios-Escalante P.,Catholic University of Temuco
Crustaceana | Year: 2011
The inland water bodies of northern Chile (18-27°S) are characterized by high salinity levels and impoverished species richness. This study presents field observations of species associations sampled from shallow water bodies in the Antofagasta region of northern Chile (23°S). A species presenceabsence matrix was created for calculating the Jaccard Index of community similarity and for testing null models of species associations, with the aim of determining whether species associations, are random or not. The results of the Jaccard Index calculations indicated the existence of defined groups, including three sites with Artemia franciscana, two sites with Boeckella poopoensis, and a sixth site only containing the ostracod Sarscypridopsis aculeata. The results of the null model analysis denoted the presence of regulating factors only in fixed-fixed simulation, that is the most robust in comparison to the other two simulations that denoted absence of regulator factors in species associations. The Jaccard indices and significant null model analysis agree with previous ecological descriptions of salinity as a determinant of species associations, whereas the non-significant results of the other two simulations could be due to the low number of species reported. The ecology and biogeography of these communities are also discussed. © 2011 Koninklijke Brill NV, Leiden.
Aldunate R.,Catholic University of Temuco |
Nussbaum M.,University of Computer Science of Chile
Computers in Human Behavior | Year: 2013
Technology adoption is usually modeled as a process with dynamic transitions between costs and benefits. Nevertheless, school teachers do not generally make effective use of technology in their teaching. This article describes a study designed to exhibit the interplay between two variables: the type of technology, in terms of its complexity of use, and the type of teacher, in terms of attitude towards innovation. The results from this study include: (a) elaboration of a characteristic teacher technology adoption process, based on an existing learning curve for new technology proposed for software development; and (b) presentation of exit points during the technology adoption process. This paper concludes that teachers who are early technology adopters and commit a significant portion of their time to incorporating educational technology into their teaching are more likely to adopt new technology, regardless of its complexity. However, teachers who are not early technology adopters and commit a small portion of their time to integrating educational technology are less likely to adopt new technology and are prone to abandoning the adoption at identified points in the process. © 2012 Elsevier Ltd. All rights reserved.
Marcos R.,Autonomous University of Barcelona |
Carmona E.R.,Catholic University of Temuco
Methods in Molecular Biology | Year: 2013
In spite of its pioneer use in detecting mutational processes, Drosophila has yet an important role in studies aiming to detect and quantify the induction of DNA damage. Here we describe two assays, one detecting primary damage (the Comet assay) and the other detecting somatic mutation and recombination effects (wing-spot test). It is important to emphasize that somatic recombination is a key event in cancer and no assays exist to detect and quantify somatic recombination processes, other than the spot tests developed in Drosophila. © Springer Science+Business Media, New York 2013.