Staff Perceptions on the Qualities of Meaningful Relationships with Residents at End of Life in Long Term Care

Long Term Care is a place where many people die, and it is the job of the staff members to assist the resident with their dying and death experience. A peaceful transition to death is largely dependent on the relationship between resident and staff members. In order to provide the best dying and death experience for the resident, I sought to explore staff perceptions on the qualities of a meaningful relationship with resident at the end of life. Using interpretive phenomenology as a qualitative research design and Heidegger’s (1962) concept of the lifeworld as a tool of analysis, I uncovered aspects of good ethical care by listening to the people who provide it. I completed a series of nine interviews and depicted staff perceptions of the qualities of their relationships with residents at the end of life. My data analysis uncovered three qualities of staff and resident relationship that positively influenced the dying and death experience for resident. These qualities are fearlessness, meaningful time and vulnerability. Furthermore, these findings reflect the mutual giving and receiving of care for both staff and resident throughout this relationship. Often this complex dynamic can be misunderstood or masked by what ministry standards tell us in how this relationship should look in LTC. My research exposes a different side of care at the end of life. With all the unknowns a resident is faced with at the end of life, the emotional relationship between resident and staff member can be the most comforting

Equações de afilamento e volume para tamanhos comerciais de nothofagus obliqua e N. alpina

Timber volume of standing trees is essential information for managementdecisions. The increasing need to optimize the potential capacity of forests maintaining their conservation, requires the quantification of the different potential possible timber products. The aim was to adjust taper equations to determine volumes of different timber products for commercial stems of Nothofagus alpina and N. obliqua. Trees of both species were randomly selected in harvesting areas of Lanin National Park (Argentina).Trees were felled and cut into commercial logs, measuring diameter with bark at different heights up to the beginning of the crown, and for each tree the diameter at breast height and total height. Five taper equations were selected and non-linear regression processes were employed for the fittings. We obtained the volume through the integration of the stem profile equation and the rotation in the space thereof through solid of revolution.The Bennet and Swindel (1972) model was selected for both Nothofagus species,obtaining similar equation parameters and differences were observed at the top of the stems of larger trees. For this the use of an integrated model is not recommended. With the obtained equations it is possible to: (i) estimate volume at different heights and for different commercial diameters, and (ii) predict the height at which both species reach to a certain diameter. The model presented some statistical limitations (e.g. multicollinearity), however, the fitting of the equation and the easy understanding of the outputs support itas a useful tool in a broad range of forest applications.O volume de madeira das árvores em pé é uma informação essencial para as decisões de gestão. A crescente necessidade de otimizar a capacidade potencial das florestas mantendo sua conservação, requer a quantificação dos diferentes possíveis produtos de madeira possíveis. O objetivo era ajustar equações de afilamento para determinar volumes de diferentes produtos de madeira para hastes comerciais de Nothofagus alpina e N. obliqua. As árvores de ambas as espécies foram selecionadas ao acaso nas áreas de colheita do Parque Nacional Lanin (Argentina). As árvores foram derrubadas e cortadas em troncos comerciais, medindo o diâmetro com a casca em diferentes alturas até o início da coroa, e para cada árvore o diâmetro na altura do peito e altura total. Foram selecionadas cinco equações cônicas e foram empregados processos de regressão não-linear para ajustar. Obtivemos o volume através da integração da equação do perfil do caule e da rotação no seu espaço através do sólido da revolução. O modelo de Bennet e Swindel (1972) foi selecionado para as duas espécies de Nothofagus, obtendo parâmetros de equação semelhantes e observando-se diferenças no topo das hastes de árvores maiores. Portanto, o uso de um modelo integrado não é recomendado. Com as equações obtidas é possível: (i) estimar o volume em diferentes alturas e para diferentes diâmetros comerciais, e (ii) prever a altura em que ambas as espécies atingem um determinado diâmetro. O modelo apresentou algumas limitações estatísticas (por exemplo, multicolinearidade), no entanto, o ajuste da equação e a compreensão fácil das saídas o suportam como uma ferramenta útil em uma ampla gama de aplicações florestais.Fil: Attis Beltran, Hernan. Universidad Nacional del Comahue; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Chauchard, Luis. Universidad Nacional del Comahue; ArgentinaFil: Iaconis, Ariana. University of Sydney; AustraliaFil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentin

índice de sítio diamétrico: um método alternativo para estimar a qualidade do sítio em florestas de Nothofagus obliqua E N. alpina

The first step for constructing models of tree growth and yield is site quality assessment. To estimate this attribute, several methodologies are available in which site index (SI) is a standard one. However, this approach, that uses height at a reference age of trees, can be simplified if age is replaced by another reference variable easier to measure. In this case, the diametric site index (DSI) represents the mean height of dominant trees at a reference mean diameter at breast height. The aim of this work was to develop DSI in pure and mixed Nothofagus alpina and N. obliqua forests, and compare these models with the classical proposals based on height-age variables, within the temperate forest of northwestern Patagonia from Argentina, South America. Data originated from temporary plots and stem analyses were used. Tree age and diameter at breast height were obtained from each plot and used for establishing DSI family functions, following the guide-curve methodology. Site classes were proportionally represented among DSI curves of 17.0, 21.5, 26.0, 30.5 and 35.0 m of dominant tree height. Reference diameter instead of reference age can be cautiously used in order to fit site index models.Primeiro passo para a construção de modelos de crescimento e produção de árvores e a avaliação da qualidade do sítio. Para estimar este atributo, várias metodologias estão disponíveis, na qual o índice de sítio (IS) é padrão. No entanto, esta abordagem, que utiliza uma altura na idade de referência, pode ser simplificada se a idade é substituída por outra variável de referência mais fácil de medir. Neste caso, o índice de índice de sítio diamétrico (ISD) representa a altura média das árvores dominantes de um diâmetro à altura do peito referência. O objetivo deste trabalho foi desenvolver ISD para florestas puras e mistas de Nothofagus alpina e N. obliqua, e comparar esses modelos com as propostas clássicas baseadas nas variáveis altura-idade, para a floresta temperada do noroeste da Patagônia da Argentina, América do Sul. Dados provenientes de parcelas temporárias e análises de tronco foram utilizados. Foram obtidos idade e diâmetro à altura do peito de cada parcela e utilizados para o estabelecimento das funções da família DSI, seguindo a metodologia da curva-guia. Classes de sítio foram proporcionalmente representados entre curvas DSI de 17,0; 21,5; 26,0; 30,5 e 35,0 m de altura da árvore dominante. O diâmetro de referência em vez da idade de referência pode ser usado com cautela para ajustar modelos de índice de sítio.Fil: Attis Beltran, Hernan. Universidad Nacional del Comahue. Asentamiento Universidad San Martin de Los Andes; Argentina. Universidad Nacional del Comahue; ArgentinaFil: Chauchards, Luis Mario. Universidad Nacional del Comahue; ArgentinaFil: Velásquez, Abel. Universidad Nacional del Comahue; ArgentinaFil: Sbrancia, Renato. Universidad Nacional del Comahue; ArgentinaFil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional del Comahue; Argentin

An Investigation of the Variables That Predict Teacher E-Learning Acceptance

Because of advancements in information communication technologies (ICT), education has evolved in terms of how the students are taught and how students learn. Education can take place in a traditional setting and/or a virtual learning environment (VLE). Consequently, the purpose of this quantitative predictive study was to examine variables that best predict the e-learning acceptance of public school K-12 e-learning teachers. Using a hierarchical regression analysis to analyze 112 teacher survey responses, results demonstrated that the model consisting of the predictor variables (i.e., demographics and experience variables, computer anxiety, computer self-efficacy, technological complexity, perceived convenience, perceived usefulness, and perceived ease of use) accounted for 48.3% of the variance in e-learning acceptance. Computer anxiety made the most significant contribution to the variance of the e-learning acceptance model and perceived convenience made the most individual significant contribution to the final model. Implications and recommendations for future research are subsequently presented

Compatibilidad entre la conservación de la diversidad biológica y la producción en una plantación forestal en la Patagonia noroccidental argentina

La diversidad biológica y la productividad de un ecosistema representan indicadores clave de integridad ambiental que son afectados significativamente por la introducción de especies. Las plantaciones forestales con árboles exóticos proveen bienes y servicios imprescindibles para la humanidad, aunque disminuyen la riqueza de plantas y animales cuando conforman monocultivos coetáneos de alta densidad. Este estudio evaluó la compatibilidad ambiental y económica de una plantación de Pinus ponderosa (Pinaceae), localizada en el campo forestal Litrán del noroeste de la Patagonia argentina (38° 54' S y 71° 01' O, 1.400 msnm., 1.310 ha). El análisis involucró la medición de parámetros físicos y biológicos y la producción de madera en comunidades con una variada estructura poblacional. En el área de estudio, el invierno es frío y húmedo y el verano cálido y seco. La litología corresponde a basaltos y andesitas cubiertas por tefra Holocénica, que proporcionan el material parental volcánico de los Andisoles predominantes. La vegetación corresponde a la transición entre la estepa patagónica de pastos y arbustos y el bosque subantártico. Los pinos se plantaron en la estepa entre 1991 y 1995 y actualmente conformaron rodales abiertos (RA, 30 m 2 /ha). En cada categoría se estimó la producción de madera, con el modelo regional de rendimiento para P. ponderosa "Piltriquitrón" con un turno de corta de 36 años. En cada rodal y en el pastizal circundante de referencia se estimaron la diversidad de plantas y la cantidad de suelo desnudo a través de datos de incidencia presencia / ausencia. Los rodales presentaron la misma calidad de sitio y una cobertura aérea de 29; 63 y 91% en RA, RI y RC, respectivamente. En RA, RI y RC, la producción total de madera se estimó en 334, 426 y 456 m3 /ha, respectivamente, mientras que la productividad total en 9,3; 11,8 y 12,7 m 3 /ha/año, respectivamente. En RA, RI y RC, la riqueza de plantas fue 30, 16 y 16 especies, respectivamente, mientras que el índice de diversidad fue 5,2; 1,7 y 1,3, respectivamente. La riqueza y diversidad de plantas del pastizal fue 45 y 6,4, respectivamente. En RA, la producción de madera fue 32% menor, la riqueza de especies fue el doble, la diversidad fue hasta 3,5 veces mayor y la proporción de suelo desnudo fue tres veces menor a la de RI y RC. Estudios previos en sistemas productivos equivalentes encontraron una diversidad menor a la del pastizal, que aumentó en rodales estructuralmente más complejos. La correlación negativa que existió entre la productividad y la diversidad se debe tener en cuenta para implementar escenarios de sustentabilidad en estos hábitats antropogénicos. La compatibilidad entre la conservación de especies silvestres y la producción de madera requiere esencialmente mantener rodales abiertos a lo largo del ciclo de corta. Aunque tales proyectos forestales puedan presentar una productividad de madera menor, podrán tener un valor ecosistémico y estético mayor que aumentará la posibilidad de sostenerlos económicamente por parte de la sociedad.Biodiversity and productivity are ecosystem integrity key indicators that are significantly affected by species introduction. Forest plantations based on exotic trees provide goods and services essential to humanity, although they diminish plant and animal richness when constitute even-aged monocultures of large density. In this study the environmental and economic sustainability of a Pinus ponderosa (Pinaceae) plantation, located in Litrán within northwestern Patagonia of Argentina (38° 54' S and 71° 01' W, 1,400 masl, 1,310 ha), was evaluated. The analysis involved physical and biological variables and wood production, measured in communities with contrasting population structures. In the study area, winter is cold and wet and summer is warm and dry. Lithology comprised basalts and andesites covered by Holocene tephra, which provide the volcanic parent material of the predominant Andisols. Vegetation corresponded to the transition between the Patagonian semirarid steppe of grasses and shrubs and the subantarctic temperate forest. Pines were planted between 1991 and 1995 in the steppe, and at present, they constituted open (RA, 30 m2 /ha). In these structural classes, timber production was estimated with the regional production model for P. ponderosa "Piltriquitrón" with a rotation length of 36 years. In each stand and in the surrounding grassland as the reference community, plant diversity and bare soil were estimated through incidence presence / absence data. Stands exhibited an equivalent site quality and canopy cover was 29; 63 and 91% for RA, RI and RC, respectively. In RA, RI and RC, final timber production was 334, 426 and 456 m3 /ha, respectively, and productivity was 9.3, 11.8 and 12.7 m3 /ha/yr., respectively. In RA, RI and RC, plant richness was 30, 16 and 16 species, respectively, and diversity index was 5.2, 1.7 and 1.3, respectively. Plant richness and diversity of grassland were 45 species and 6.4, respectively. In RA timber production was 32% lower, richness twice, diversity up to 3.5 times higher and bare soil proportion three times lesser in comparison to RI and RC. Previous studies in analogous production systems found a lower diversity compared to grassland, but it increased in structurally more complex stands. The negative correlation between timber production and biological diversity should be considered for implementing sustainability scenarios within these anthropogenic habitats. The compatibility between wildlife preservation and timber production basically requires keeping open stands along the entire production cycle. Although such projects would represent a lower economic income from timber, they would have a larger ecosystem and aesthetic value that will increase the possibility of supporting them by society.Fil: Dezzotti, Alejandro. Universidad Nacional del Comahue. Asentamiento Universidad San Martín de Los Andes; ArgentinaFil: Sbrancia, Renato. Universidad Nacional del Comahue. Asentamiento Universidad San Martín de Los Andes; ArgentinaFil: Mortoro, Ariel. Universidad Nacional del Comahue. Asentamiento Universidad San Martín de Los Andes; ArgentinaFil: Attis Beltran, Hernan. Universidad Nacional del Comahue. Asentamiento Universidad San Martín de Los Andes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Sustained striatal ciliary neurotrophic factor expression negatively affects behavior and gene expression in normal and R6/1 mice

Huntington's disease (HD) is a neurodegenerative disorder caused by an elongation of CAG repeats in the HD gene, which encodes a mutant copy of huntingtin with an expanded polyglutatmine repeat. Individuals who are affected by the disease suffer from motor, cognitive, and emotional impairments. Levels of certain striatal-enriched mRNAs decrease in both HD patients and transgenic HD mice prior to the development of motor symptoms and neuronal cell death. Ciliary neurotrophic factor (CNTF) has been shown to protect neurons against chemically induced toxic insults in vitro and in vivo. To test the hypothesis that CNTF might protect neurons from the negative effects of the mutant huntingtin protein in vivo, CNTF was continuously expressed following transduction of the striatum by recombinant adeno-associated viral vectors (rAAV2). Wild-type and R6/1 HD transgenic (R6/1) mice that received bilateral or unilateral intrastriatal injections of rAAV2-CNTF experienced weight loss. The CNTF-treated R6/1 HD transgenic mice experienced motor impairments at an earlier age than expected compared with age-matched control R6/1 HD transgenic animals. CNTF also caused abnormal behavior in WT mice. In addition to behavioral impairments, in situ hybridization showed that, in both WT and R6/1 mice, CNTF expression caused a significant decrease in the levels of striatal-enriched transcripts. Overall, continuous expression of striatal CNTF at the dose mediated by the expression cassette used in this study was detrimental to HD and wild-type mice. © 2008 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/58641/1/21636_ftp.pd

Mixed Nothofagus forest management: a crucial link between regeneration, site and microsite conditions

Canopy openings due to harvesting practices constitute a disturbance that changes the environmental conditions of microsites. Its impact on the relative performance of the regeneration of different tree species could also be affected by site conditions and forest structure.The objective of this study was to determine how regeneration establishment of Nothofagus mixed forests is influenced by shelterwood silvicultural system. We focused on Lanín National Reserve (Neuquén, Argentina) where this silvicultural system has been applied since the late 1980s. The microsite scale analysis (one managed forest) showed that canopy cover was a key factor conditioning Nothofagus regeneration establishment, with older and larger individuals growing in less exposed microsites. Low understory dominance and leaf litter thickness were also associated with microsites with regeneration, while successful establishment (saplings taller than 2 m) showed positive correlation with soil moisture. Variations of these patterns were observed among species reflecting their specific ecophysiological requirements. On a stand scale (two managed forests along Lacar watershed) regeneration of N. dombeyi and N. alpina showed significant correlation with site and specific basal area, while N. obliqua was correlated with total basal area. Regeneration taller than 2 m was mainly correlated with site and altitude. At both, microsite and stand scale, the relative abundance of species changed between mature trees and regeneration. In particular, for N. alpina, an abundance decrease was observed on regeneration. Our results suggest that forest management systems should diversify silvicultural practices throughout the forest landscape, to provide at each site the micro-environmental conditions required by each species in order to maintain biodiversity and forest functions.Estación Experimental Agropecuaria BarilocheFil: Sola, Georgina Giselle. Universidad Nacional del Comahue. Cátedra de Ordenación Forestal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. CCT-Patagonia Norte; ArgentinaFil: El Mujtar, Veronica Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Área Sistemas Forestales. Unidad de Genética Ecológica y Mejoramiento Forestal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Attis Beltran, Hernan. Universidad Nacional del Comahue. Cátedra de Ordenación Forestal; ArgentinaFil: Chauchard, Luis Mario. Universidad Nacional del Comahue. Cátedra de Ordenación Forestal; ArgentinaFil: Gallo, Leonardo Ariel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Área Sistemas Forestales. Unidad de Genética Ecológica y Mejoramiento Forestal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Tree health influences diameter growth along site quality, crown class and age gradients in Nothofagus forests of southern Patagonia

We examined the influence of tree health on annual diameter increment of trees along gradients in stand site quality, crown classes and tree age in Nothofagus pumilio forests of Southern Patagonia. Healthy trees had higher annual diameter increment than unhealthy trees along all gradients (site quality, crown class, tree age). We argue that tree health could be employed as a qualitative variable in models of tree growth to estimate aboveground biomass and carbon stocks in this forest system.Fil: Attis Beltran, Hernan. Universidad Nacional del Comahue. Asentamiento Universidad San Martin de Los Andes; ArgentinaFil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Ivancich, Horacio Simón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Lencinas, María Vanessa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Chauchards, Luis Mario. Universidad Nacional del Comahue. Asentamiento Universidad San Martin de Los Andes; Argentina. Administración de Parques Nacionales; Argentin

Effect of silvicultural management on the Nothofagus dombeyi, N. alpina and N. obliqua forest regeneration within the Lanín Natural Reserve (Argentina)

Las prácticas silviculturales constituyen un importante agente de disturbio y su inadecuada implementación afecta la sostenibilidad de los bosques naturales. En la Reserva Nacional Lanín, el manejo silvicultural del bosque de Nothofagus dombeyi, N. alpina y N. obliqua se realiza tradicionalmente mediante aclareos sucesivos; y se desconoce su efecto sobre la composición y estructura de la regeneración natural. La cobertura del dosel, composición y área basal de los individuos adultos, y la composición, edad y distribución espacial de los renovales fue evaluada en una parcela de 3 ha intervenida en 1993 mediante una corta diseminatoria. La densidad de adultos antes de la corta fue 26 % para N. dombeyi, 38 % para N. alpina y 35 % para N. obliqua, y la remanente fue 20, 44 y 36 %, respectivamente. Previamente al aprovechamiento, el 92 % de la regeneración estaba constituida por N. alpina, y luego principalmente por N. obliqua (45 %) y N. dombeyi (42 %). Estos valores no se correlacionaron con el área basal de adultos. La edad de los renovales fue mayor en sitios con alta cobertura de dosel y N. alpina fue la especie que se instaló última. El aprovechamiento del bosque de Nothofagus no promovió el mantenimiento de la composición relativa original de la regeneración. El tiempo de colonización de las especies de Nothofagus disminuiría y una mayor cantidad de renovales de N. alpina, especie más tolerante a la sombra, se establecería si la cobertura remanente fuera superior a la recomendada en los planes de manejo.Management practices are important disturbance agents at local level and their incorrect implementation may affect the sustainability of natural forests. Usually, silviculture based on the shelterwood system was carried out in the mixed stands composed of Nothofagus dombeyi, N. alpina and N. obliqua, located at Lanín Natural Reserve (Neuquén Province, Argentina). However, the effect of this scheme on the composition and structure of natural regeneration is still rather unknown. In this study, composition, age, abundance and spatial pattern of adults and saplings of Nothofagus species were evaluated in a 3-ha plot logged in 1993. At pre-harvest period, adult density was 26 % for N. dombeyi, 38 % for N. alpina and 35 % for N. obliqua. Regeneration consisted mainly of N. nervosa. After logging, composition of adult trees was 20 %, 43 % and 37 % for N. dombeyi, N. alpina, N. obliqua, respectively; whereas regeneration was 45 % for N. obliqua and 42 % for N. dombeyi. Within species, no relationship was found between basal area of adult trees and density of saplings. For all tree species, age regeneration was larger in areas where tree canopy cover exhibited higher values. N. alpina was the last installed species. Preservation of the relative species composition after logging did not maintain the original abundance within regeneration. Consequently, it is necessary to adjust silvicultural practices, and particularly the level of canopy openings, in order to maintain species composition unaffected as a key indicator of sustainability at management unit scale.Fil: Sola, Georgina Giselle. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Grupo de Genética Forestal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Comahue. Asentamiento Universidad San Martín de Los Andes; ArgentinaFil: Attis Beltran, Hernan. Universidad Nacional del Comahue. Asentamiento Universidad San Martín de Los Andes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Chauchards, Luis Mario. Universidad Nacional del Comahue. Asentamiento Universidad San Martín de Los Andes; ArgentinaFil: Gallo, Leonardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Grupo de Genética Forestal; Argentin

Diametric growth model of Nothofagus alpina and its relationship with that of Nothofagus obliqua and Nothofagus dombeyi in the natural forest from Patagonia of Argentina

Los modelos de crecimiento arbóreo contribuyen a describir la estructura y el funcionamiento del bosque, predecir la producción de madera, implementar alternativas silvícolas y evaluar la dimensión económica forestal. Nothofagus alpina, Nothofagus obliqua y Nothofagus dombeyi (Nothofagaceae) conforman bosques naturales en el noroeste de la Patagonia argentina. A través de la función von Bertalanffy-Richards, se desarrolló un modelo de incremento corriente y rendimiento en diámetro para N. alpina de los estratos intermedio y superior, y se los comparó con los existentes para N. obliqua y N. dombeyi. En las tres especies, los árboles intermedios exhibieron el menor crecimiento que se debería a la composición y menor cantidad de luz. El crecimiento de N. alpina, comparado con el de N. dombeyi, fue similar en todas las clases de edad para el estrato intermedio, y menor en las clases de mayor edad para el estrato superior. Sin embargo, el desempeño de esta especie fue muy adecuado en ambos estratos, que se asociaría a la mayor tolerancia a la sombra (percibida en el estrato intermedio) y la respuesta al aumento de la luz (en el superior). Nothofagus obliqua siempre presentó el crecimiento diamétrico más lento. Las discrepancias observadas en los modelos fueron compatibles con diferencias interespecíficas de crecimiento intrínseco y demanda de luz. La interpretación simultánea de los modelos de estas especies de Nothofagus contribuye a aumentar la comprensión ecológica y productiva de un valioso tipo de vegetación subantártica.Tree growth models contribute to describing the structure and functioning of forests, predicting timber production, implementing appropriate silvicultural practices and assessing the economic dimension of forestry. Nothofagus alpina, Nothofagus obliqua and Nothofagus dombeyi (Nothofagaceae) form natural forests in Northwestern Patagonia of Argentina. Models of diametric increment and yield were developed for N. alpina trees from the intermediate and superior canopy strata, through Bertalanffy - Richards's functions. They were interpreted together with those for N. obliqua and N. dombeyi, formerly developed using the same methodology. In all three species, intermediate trees exhibited the lowest diametric growth, probably in response to differences in the amount and composition of light. Growth of N. alpina trees, compared to N. dombeyi, was similar for all age classes within the intermediate stratum, and lower for older classes within the superior stratum. However, the performance of this species was adequate in both strata, which would be associated with the superior shade tolerance (perceived in the intermediate stratum) and the response to increasing light (in the upper one). Nothofagus obliqua experienced the slowest growth for all social strata and age classes. Discrepancies observed among models were compatible with interspecific differences in intrinsic growth and demand of light. The simultaneous interpretation of growth models of N. alpina, N. obliqua and N. dombeyi can contribute to deeply understand ecological patterns and processes of this subantarctic forest, aimed at its conservation and sustainable management.Fil: Attis Beltran, Hernan. Universidad Nacional del Comahue; ArgentinaFil: Chauchards, Luis Mario. Universidad Nacional del Comahue; ArgentinaFil: Dezzotti, Luciana. Universidad Nacional del Comahue; ArgentinaFil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentin