24 research outputs found
Ansiedad ante la muerte en la adolescencia
[Resumen] Con este trabajo se pretende profundizar en
el conocimiento de la ansiedad ante la muerte
en la adolescencia determinando si hay diferencias
significativas en aquélla en función de
diferentes variables. Para ello se ha aplicado
la Death Anxiety Scale -DAS-, de Templer
(1970), a 505 sujetos (266 mujeres y 239
varones) con un rango de edad de 16 a 19 años
(edad media = 16.99, DT=.96). Los resultados
obtenidos muestran que las/los adolescentes
obtienen una puntuación media en la DAS de
8.013 (DT=3.492). Se encuentran diferencias
significativas en las puntuaciones obtenidas
en la DAS en función del sexo, religión, práctica
religiosa y opción política.[Abstract] With this work it is sought to deepen in the
knowledge of the anxiety in the face of the
death in the adolescence, determining if there
are significant differences in this actitud in
function of different variables. For it was
applied the Death Anxiety Scale of Templer
(1970) to 505 adolescents (266 women and
239 men) with an age range of 16 to 19 years
(half age= 16.99, SD = .96). The obtained
results show that the adolescents obtain a half
punctuation in the DAS of 8.013 (SD= 3.492).
We find significant differences in the punctuations
obtained in the DAS in function of the
sex, the religion, religious practice and politicalopcion
Invasive barnacle fouling on an endemic burrowing crab mobile basibionts as vectors to invade a suboptimal habitat
Neohelice (Chasmagnathus) granulata is an ecosystem engineer endemic of salt marshes and mudflats of the southwestern Atlantic coast, where several Patagonian salt marshes were invaded by the acorn barnacle Balanus glandula, a typical rocky shore species. In this work, we supply the first report of the occurrence of epibiosis of B. glandula on N. granulata in these salt marshes and we describe the major ecological features of this invader/native association in order to generate sound baseline for further investigations and management decisions. Our results show that barnacles are found in the entire dorsal and lateral surface of the crabs, and specially in vital zones such us the basal insertion of the chelipeds, walking appendages, ocular peduncles, jaws, mouth with the carapace. Furthermore, the size reached by barnacles suggest that they are sexually mature and can reproduce while fouling on the crabs, being the maximum size of barnacles tightly associated and determined by the duration of the crab's inter-molt span. Our results highlight the mechanisms by which an invasive rocky shore invader can exploit an unfavorable environment (i.e. mobile substratum) to persist on soft bottom systems.Neohelice (Chasmagnathus) granulata es un ingeniero de ecosistemas endémico de las marismas y planicies barrosas de la costa atlántica sud-occidental, donde varias marismas patagónicas han sido invadidas por el cirripedio Balanus glandula, una especie típica de intermareales rocosos. En este trabajo, se proporciona el primer reporte de la ocurrencia de epibiosis de B. glandula sobre N. granulata en estas marismas y se describen las principales características ecológicas de esta asociación invasor/nativo con el objetivo de generar información de línea de base adecuada para investigaciones futuras y la toma de desiciones de manejo. Nuestros resultados muestran que los cirripedios se encuentran en la superficie dorsal y lateral de los cangrejos y, en especial, en zonas vitales como la inserción basal de los quelípedos, los apéndices caminadores, los pedúnculos oculares, las mandíbulas y la boca, con el caparazón. Además, el tamaño medio de los cirripedios sugiere que alcanzan la madurez sexual y son capaces de reproducirse mientras se encuentran adheridos a los cangrejos. Por otra parte, el tamaño máximo de los cirripedios se encuentra fuertemente asociado y determinado por la duración del intervalo entre-mudas de los cangrejos. Así, nuestros resultados ponen de manifiesto los mecanismos por los cuales un invasor de intermareales rocosos es capaz de explotar un entorno desfavorable (es decir, sustratos móviles) para persistir en intermareales de fondos blandos.Fil: Mendez, María Martha. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Sueiro, Maria Cruz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Schwindt, Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Bortolus, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentin
Benthic diversity and assemblage structure of a north Patagonian rocky shore: a monitoring legacy of the NaGISA project
The rocky shore of Punta Este, Golfo Nuevo (Patagonia, Argentina), was sampled using the standardized NaGISA (CoML) protocol aimed to generate biodiversity baseline data in 6 levels, from high intertidal to 10m depth. Based on the generated data, we studied the benthic assemblage structure, species richness, mean abundance and the distribution pattern of invertebrate functional groups, typifying species in each intertidal and subtidal level. The rocky shore studied, as other in north Patagonia is understudied, factors driven its assemblage structure are not clear yet. The intertidal sampled is exposed to extreme physical conditions higher than any other studied rocky shore systems, with air temperature variation of 40°C during the year, maximum winds of 90 km/h and semidiurnal tides of 5m amplitude; on the other hand subtidal presents less thermal variation (DeltaT 10°C along the year) and more homogeneous physical conditions. We identified 65 taxa represented by six animal phyla: Mollusca, Arthropoda, Annelida (Polychaeta), Echinodermata, Cnidaria and Nemertea; and three algal phyla: Chlorophyta, Rhodophyta and Heterokontophyta (class: Phaeophyceae). Ordination nMDS plots showed three different assemblages in terms of species composition (intertidal, subtidal 1m level and subtidal 5-10m samples). The intertidal was represented by suspension feeders mainly Mollusca. The tiny mussels Brachidontes rodriguezii and Brachidontes purpuratus, and the algae Corallina officinalis dominated the intertidal and acts as a buffer that prevent other species for physical stress. The subtidal was mainly represented by grazers. Our results showed a tendency of suspension feeders decreasing and increasing of grazers and predators from high intertidal to subtidal, probably driven by decreasing in physical stress. The gastropod Tegula patagonica, the sea urchins Arbacia dufresnii and Pseudechinus magellanicus and the non native algae Undaria pinnatifida were the most abundant in 1m-10m level. Based on previous works performed in the region, we hypothesize that the differences registered between intertidal and subtidal samples could be explained in part by an increase in physical stress in the intertidal with low predation pressure that promotes positive interactions, while in the subtidal the increasing in consumers and decreasing of physical stress could lead to associational defenses. Competition for primary substrate at the intertidal and subtidal must be explored in future experiments. Our results could be useful to compare data and to develop a sustainable network for long-term monitoring benthic community changes due to anthropogenic activities.Fil: Rechimont, Maria Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Galvan, David Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Sueiro, Maria Cruz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Casas, Graciela Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Piriz, Maria Luz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Diez, María Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Primost, Monica Angelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Zabala, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Marquez, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Brogger, Martin Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; ArgentinaFil: Fernandez Alfaya, Jose Elias. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Bigatti, Gregorio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin
Descripción y alternativas de mitigación de los impactos ambientales negativos por la introducción de la crianza del búfalo (Bubalus bubalis)
A number of alternatives to diminish negative environmental impacts before introducing buffalo (Bubalus bubalis) breeding in two livestock centers from MINAZ (Ministry of Sugar Cane Industry) in Granma province, Cuba are described. Research included eight units located in Bayamo, Manzanillo, Yara, and Bartolomé Masó municipalities. It dealt with the study of soil, water, climate, and biodiversity conditions to create a productive system guaranteeing environment conservation and monitoring, as well as the epidemiological surveillance of the introduced species and the directly exposed workers to the breeding system besides the preservation of buffalo, as a genetic resource, against extreme climate events. An environment monitoring program is presented. There were no negative environmental impacts preventing buffalo breeding in the studied livestock centers.Se describieron y propusieron alternativas de mitigación de impactos ambientales negativos para la introducción de la crianza del búfalo (Bubalus bubalis) en dos empresas agropecuarias azucareras en la provincia Granma, Cuba. Los estudios abarcaron la situación del suelo, agua, clima y la biodiversidad, para la conformación de un sistema productivo que facilitara la conservación del medio ambiente y su monitoreo, incluida además la vigilancia epidemiológica de la especie, así como la de los trabajadores directamente expuestos al sistema de crianza, y la preservación del búfalo como recurso genético frente a eventos extremos del clima. Se presenta un programa para el monitoreo de esta actividad. No se identificaron impactos ambientales que imposibiliten la crianza de esta especie en las áreas designadas
Vascular plants as modifying agents of coastal patagonian ecosistems
En las costas de Patagonia, aquellos ambientes costeros que poseen la fisonomía típica de un intermareal rocoso pero están dominados por el tipo de plantas vasculares que dominan y caracterizan las marismas de sustratos blandos se han designado recientemente como marismas rocosas. Spartina densiflora, la especie vegetal dominante en la mayoria de las marismas rocosas relevadas, es considerada un organismo bioingeniero gracias a su capacidad de modificar, mantener, y/o crear hábitats. En este trabajo se describen las variables físicas y biológicas en areas donde esta especie vegetal se halla presente y se estudian cuales son los efectos que ejerce sobre la estructuración de los ensambles de macroinvertebrados asociados. Se encontró que la presencia de esta halofita amortigua las condiciones físicas estresantes de los ambientes intermareales y que los ensambles de macorinveretabrados asociados a su presencia difieren en su distribución y abundancia con respecto a los sitios vecinos sin vegetación. La realización de experimentos manipulando la presencia de S. densiflora, mediante transplantes de plantas vivas así como de estructuras artificiales que imitan su arquitectura, permitió evidenciar el efecto positivo que ejercen esta halófita sobre la abundancia y riqueza de los macroinvertebrados presentes en las marismas rocosas estudiadas. Se encontró además que tal efecto es llevado a cabo principalmente por la estructura física que proveen las plantas, independientemente de sus propiedades biológicas y ecológicas. Los resultados que presento en esta Tesis muestran que este efecto actúa no solo sobre las especies nativas, sino que también favorece la presencia de una especie invasora de crustáceo. Estos resultados aportan información novedosa y destacan la importancia del rol que desempeña la bioingeniera Spartina densiflora en la estructuración de las comunidades de invertebrados en marismas rocosas de Patagonia. La Tesis expone y discute diversos mecanismos por medio de los cuales la estructura fisica y complejidad ambiental generada por organismos bioingenieros pueden condicionar la composición faunística en tiempo y espacio.On Patagonian coasts, those environments which have the typical appearance of a rocky intertidal but are dominated by the type of vascular plants that dominate and characterize soft substratum salt marshes were recently designated as rocky salt marshes. Spartina densiflora, the dominant plant species in the rocky salt marshes surveyed, is considered a bioengineer due to its ability to modify, maintain, and / or create habitats. This study describes the physical and biological variables that are associated with the presence of this plant species and evaluates its effects on the structure of the associated macroinvertebrate assemblages. It was found that the presence of S. densiflora buffered of the stressful physical variables of intertidal environments and that their associated macroinvertebrate assamblages differ in their distribution and abundance from those found on unvegetated patches. Through manipulative experiments that included transplants of live plants and plastic structures simulating the architecture of S. densiflora, it was found that this halophyte has a positive effect on the abundance and richness of macroinvertebrate assemblages and that its physical structure was the major factor influencing the assemblages. This positive effect acted not only on local invertebrate species, but also favors the presence of a non native species of crustacean. These results provide novel information and highlight the central role played by the bioengineer Spartina densiflora in structuring invertebrate communities in Patagonian rocky salt marshes.Fil:Sueiro, María Cruz. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina
Immunological and health-state parameters in the Patagonian rockfish Sebastes oculatus. Their relation to chemical stressors and seasonal changes
We present the results of a field study that evaluates whether exposure to anthropogenic pollution impacts immunological and health-state parameters of wild marine fish during the breeding and non-breeding periods. We assessed aspects of innate immunity (bactericidal capacity, bacterial agglutination, and leukocyte profile) and general health-related parameters (neutrophil to lymphocyte ratio, hematocrit, and condition factor) in the Patagonian rockfish (Sebastes oculatus) sampled from polluted (exposed) and reference (control) sites during winter (i.e., coolest temperatures and active reproductive period) and in summer (i.e., warmest temperatures and non-reproductive period). Results showed lower bactericidal competence, hematocrit, and condition factor in fish from exposed sites independently of season, whereas lymphocytes were higher and monocytes lower at the exposed site only during summer. Moreover, fish sampled during winter displayed lower bactericidal competence, hematocrit, and condition factor than those sampled in summer independently of site, whereas the opposite pattern was found for bacterial agglutination. These results could be explained by life-history theory, which predicts a re-allocation of resources between reproduction and other physiological functions (including immunity) during the most energetically demanding season. The present results show an alteration in immunological and health-state parameters of wild marine fish exposed to anthropogenic pollution independently of season, which could potentially result in higher susceptibility to disease and in turn population decline.Fil: Sueiro, Maria Cruz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Palacios, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin
Parasite infection and immune and health-state in wild fish exposed to marine pollution
Association between parasitism and immunity and health-state was investigated in wild Sebastes oculatus after having determined that pollution exposure is associated with altered immune and health-state parameters. Given the importance of the immune system in antiparasite defense we predicted: (i) parasite infection would be higher in pollution-exposed than in control fish and (ii) fish with lower immune and health-state parameters would show higher parasitism than fish in better condition. Metazoan parasite fauna was compared between pollution-exposed and non-exposed fish and parasitic indices were correlated with integrated measures of immunity and health-state. Results provided little support for the predictions; some parasite taxa increased, some decreased, and some were not affected in pollution-exposed fish despite their altered health and immunity. Furthermore, there was no link between individual immune and health-state parameters and parasitism. These findings highlight the complexity of host-parasite-environment interactions in relation to pollution in natural marine ecosystems.Fil: Sueiro, Maria Cruz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Bagnato, Estefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Palacios, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentin
Epitheliocystis in wild marine fishes and its relation with anthropogenic pollution
Epitheliocystis is a fish disease with recorded in increasing numbers globally. Here we show that (a) pollution-exposed wild marine fishes have higher infection prevalence than nonexposed individuals from reference sites, suggesting that anthropogenic pollution predisposes individuals to this disease in natural systems, (b) the effect of pollution on infection status did not vary significantly between two sympatric fish species, and (c) infected and noninfected individuals from both species did not differ significantly in selected immune and general-health parameters, a result that deserves further study with increased sample sizes.Fil: Novacovsky, Gabriela Nayla. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Palacios, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Sueiro, Maria Cruz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentin
Interactions between ecosystem engineers: a native species indirectly facilitates a non-native one
The positive impact that native species have on the survival, persistence and/or range-expansion of invasive species, is receiving increasing attention from ecologists and land managers trying to better understand and predict future invasions worldwide. Ecosystem engineers are among the best-known model organisms for such studies. The austral cordgrass Spartina densiflora is an ecosystem engineer native to South America coast, where it colonizes rocky shores that were recently successfully invaded by the acorn barnacle Balanus glandula. We conducted a field experiment combining living Spartina transplants and artificial model plants in order to address the following questions: Does the native ecosystem engineer S. densiflora facilitate the invasion of rocky shores by B. glandula? If so, how much of this facilitation is caused by its physical structure alone? We found that S. densiflora had a positive effect on the invasive barnacle by trapping among its stems, the mussels, shells and gravels where B. glandula settles. Dislodged mussels, cobbles, and small shells covered and agglutinated by living barnacles were retained within the aboveground structures of S. densiflora while the control plots (without living or artificial plant structures) remained mostly bare throughout the experiment, showing how plant structures speed the colonization process. Moreover, transplanting living Spartina and artificial Spartina models led to a maximum increase in the area covered by barnacles of more than 1700% relative to the unvegetated control plots. Our study clearly shows how a native ecosystem engineers can enhance the success of invasive species and facilitate their local spread.Fil: Sueiro, Maria Cruz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Schwindt, Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Mendez, María Martha. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Bortolus, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin