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Search Results: 1 - 10 of 356 matches for " Betancur "
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Molecular phylogenetics and evolutionary history of ariid catfishes revisited: a comprehensive sampling
Ricardo Betancur-R
BMC Evolutionary Biology , 2009, DOI: 10.1186/1471-2148-9-175
Abstract: While the topologies obtained support the monophyly of basal groups, up to ten genera validated in previous morphological studies were incongruent with the molecular topologies. New World ariines were recovered as paraphyletic and Old World ariines were grouped into a well-supported clade that was further divided into subclades mainly restricted to major Gondwanan landmasses. A general area cladogram derived from the area cladograms of ariines and three other fish groups was largely congruent with the geological area cladogram of Gondwana. Nonetheless, molecular clock estimations provided variable results on the timing of ariine diversification (~105-41 mya).This study provides the most comprehensive phylogeny of sea catfishes to date and highlights the need for re-assessment of their classification. While from a topological standpoint the evolutionary history of ariines is mostly congruent with vicariance associated with the sequence of events during Gondwanan fragmentation, ambiguous divergence time estimations hinders assessing the vicariant hypothesis on a temporal framework. Further examination of ariid fossils might provide the basis for more accurate inferences on the timing of ariine diversification.The catfish order Siluriformes is a very diverse natural group that occurs primarily in freshwater. Catfishes are widespread and their distribution encompasses all continents, even Antarctica, as evidenced by Eocene-Oligocene fossils [1]. The order includes 36 extant families and over 3000 valid species plus an estimated ~1500 undescribed species [2,3]. Several morphological and molecular studies have addressed the relationships among catfish families [e.g., [4-6]] and recent evidence indicates that large basal clades are restricted to particular continental masses, suggesting a long history of intercontinental isolation [6]. Thus, catfishes offer an exceptional opportunity for studying evolutionary and biogeographic trends. The fossil record of Siluriformes is r
Atención de la urgencia en casa: una reacción automática
Lopera Betancur,Martha Adiela;
Investigación y Educación en Enfermería , 2009,
Abstract: objetive: understanding the meaning of actions done by patient?s family members at home when an emergency situation happened and were waiting for medical attention. methodology: the particularistic ethnographic approach was used. the information was gathered from interviews and observations made to people that received emergency attention at home, in the city of medellín-colombia between january 2005 and december 2006. results: in emergency situation people delivery tasks automatically among who are next to the patient, these tasks are done to recover health, to give company to avoid patient? suffering and to organice physical space and prepare patient to receive medical attention. conclusion: it is essencial to provide education to community for people?s automatic reactions in case of emergency at home to develop safe and calmed actions.
LA ACTITUD ESTUDIANTIL SOBRE LA INVESTIGACIóN EN LA UNIVERSIDAD
Rojas Betancur,Mauricio;
Investigación y Desarrollo , 2010,
Abstract: this article presents the opinions, situations and perceptions of the young student appear on the investigation in six institutions of education superior and the way in which they perceive the scientific subject from the construction of attitude scales. problems of formation and retention of new investigators, significant bonds stand out teaching-investigation, ignorance and distrust in the university systems and little knowledge on the scientific activities of the institutions. one was, in resistance, discharge predisposition towards the scientific subject and the necessity to transform the universities for a more coherent professional formation with the needs of the social development.
La llamada por la vida: necesidades de cuidado urgente en la casa
Lopera Betancur,Martha Adiela;
Investigación y Educación en Enfermería , 2008,
Abstract: objective: to identify situations when people request urgent home care. methodology: the ethnographic approach was used. the information was gathered with interviews and observations of adult people that received urgent attention at home, in the city of medellín-colombia between january of 2005 and december of 2006. results and discussion: the people call to request urgent help when they suffer a circumstance and a necessity. circumstance, is the event of health that alters the daily life, added to critical situations in the surroundings like self diagnosis and emotion. necessities are individual and ask for immediate help when the circumstance looks urgent. the necessities found in this study were to have company; security, transport and tranquillity. conclusions: the situations that push the people to request non programmed help from their house are health events that alter daily life. the circumstances and necessities are individual matters that require of that the health services provider discover and solve them.
FALSOS PRESUPUESTOS DEL PROBLEMA DE LA IDENTIDAD PERSONAL: De la identidad personal a la identidad narrativa
Betancur,Marta Cecilia;
Estudios de Filosofía , 2005,
Abstract: this paper takes up again the problem of "personal identity" in order to show that the way it has been put leads to a dead end or to an insoluble antinomy: whether the "self" is accepted as a metaphysical entity, a permanent substance, a thing, a conscious substance or an immaterial "self" lodged in the body, or, on the contrary, an entity like this is denied and rejected as a metaphysical phantom. another intention of the work to demonstrate that the dilemma originates in a wrong exposition of the problem, supported on false assumptions deeply rooted in philosophy and accepted since modernity. such assumptions are: substantialism and cosification, psychophysic parallelism and the egocentric perspective. finally, we present and analyze the solution offered by ricoeur through "narrative identity".
SEDIMENTOLOGíA DE LAGUNAS COSTERAS: CIéNAGA GRANDE DE SANTA MARTA Y CIéNAGA DE PAJARALES
Bernal,Gladys; Betancur,Julliet;
Boletín de Investigaciones Marinas y Costeras - INVEMAR , 1996,
Abstract: ciénaga grande de santa marta and ciénaga de pajarales are the two main lagoons of the marginal lagunar system at the deltaic floodplain of magdalena river, caribbean coast of colombia. a systematic surficial sampling was carried out in such lagoons and salamanca coast. a sporadic sampling was done in other places of the deltaic plain. this paper presents results about grain size, mineralogy, organic matter contents, caco3 contents, x ray diffraction and chemical analysis of salts for sediments. sedimentologic charts, distribution schemes and provenience notes are presented.
RELACIóN ENTRE LA BIOMASA Y ALGUNAS CARACTERíSTICAS MORFOLóGICAS DE LAS BROMELIAS FITOTELMATAS DE UN BOSQUE ALTO ANDINO COLOMBIANO
ISAZA,CAROLINA; BETANCUR,JULIO;
Caldasia , 2009,
Abstract: some morphological characteristics were evaluated for six bromeliad phytotelmic species (guzmania gloriosa, racinaea tetrantha, tillandsia biflora, t. complanata, t. fendleri and t. turneri) to establish which of those can be used as indirect estimators of total biomass. the present study was performed in a high andean forest of the savanna of bogotá, colombia, at 2900 m. we collected between 32 and 64 individuals per species in different developmental stages. for each one we registered 1) number of leaves, 2) the basal rosette perimeter, 3) coverage, 4), leaf length 5) the height of the rosette; and 6) total biomass. according to the results, coverage was the variable most related with biomass. a curve fitting analysis showed that a straight line best explained the relationship between coverage and biomass. thus, the equation allows estimating biomass from coverage without the destructive sampling effect.
LA MODELACION NUMERICA COMO HERRAMIENTA PARA LA EXPLORACION HIDROGEOL óGICA Y CONSTRUCCION DE MODELOS CONCEPTUALES (CASO DE APLICACIóN: BAJO CAUCA ANTIOQUE?O)
BETANCUR,TERESITA; PALACIO,CARLOS;
DYNA , 2009,
Abstract: numerical models in hydrogeology offer a way to advance the understanding of aquifer systems besides being a simulation tool. numerical models can have an exploratory nature, and as a tool for exploration, may accompany the task of building a conceptual hydrogeology model. the ?bajo cauca antioque?o? is a colombia region where de groundwater is a strategic resource. the hydrogeology exploration and de numerical modeling proposed for the aquifer system of the ?bajo cauca antioque?o? has an exploratory nature and the purpose of helping to interpret the data and groundwater flow dynamics, of the information collected since 2003.
LA NECESIDAD DE GENERALIDAD EN CIENCIAS SOCIALES
Betancur,Marta Cecilia;
Praxis Filosófica , 2008,
Abstract: this paper tries to perform the debate regarding two positions in social sciences: a reduccionist position that states that if a discipline is scientific must follow the natural sciences model, wherefore social sciences would not achieve this status because they cannot get the universality that natural sciences achieve. in contrast to it, but without the appropriate discussion about this model, a relativist position that considers that sure enough the knowledge they get is only particular and relative to each culture, has been generated in these sciences. this position has been developed, in part, following the interpretation performed about the hermeneutic circle by martin hollis. in discussion with these conceptions, the paper states that it is possible to achieve a generality in social sciences and that, against the tendency of choosing between the universality of natural sciences and the particularity of the social ones, it is necessary to accept different generality levels. finally, with ricoeur′s help, the way in which it is possible to understand this generality sense is exposed.
Profilaxis de sangrado digestivo: Revisión bibliográfica
Betancur Jiménez,Jorge;
Revista Colombiana de Cirugía , 2004,
Abstract: gastrointestinal bleeding is an important cause of morbidity in patients admitted to hospitals for diverse reasons. however, not all exhibit similar risk of bleeding as an intercurrent event. prophylaxis of such type of bleeding must be done rationally and according to individual risk factors. we present a literature review and provide recommendations on when and how to conduct prophylaxis.
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