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El salmón de mar Pseudopercis semifasciata (Cuvier, 1829) (Pinguipedidae) es un importante recurso pesquero y turístico en los golfos norpatagónicos de Argentina, donde vive asociado a pequeños arrecifes rocosos conocidos como “salmoneras”, que sustentan actividades recreativas y comerciales de buceo y pesca deportiva, submarina y artesanal. Es una especie longeva (~30 años), de gran tamaño (supera el metro de largo y los 20 kg de peso), y baja fecundidad, lo que la convierte en un blanco potencialmente vulnerable a la pesca. Sin embargo, su explotación nunca fue regulada y la aplicabilidad de los métodos de evaluación y manejo convencionales puede ser poco viable dependiendo de sus patrones de migración y movilidad a distintas escalas espaciales. En este trabajo se analiza información sobre áreas de desove y distribución de larvas y prerreclutas en la plataforma argentina, para investigar la posibilidad de que existan migraciones reproductivas. El grado de movilidad y el patrón de ocupación de los arrecifes por salmones de distinta talla, sexo y fenotipo cromático se estudiaron mediante marcación y censos visuales subacuáticos. Se desarrolló una metodología para estimar el esfuerzo de pesca recreativa y la cosecha, la que se aplicó a datos colectados en el golfo San José durante tres temporadas de pesca, y se evaluaron los cambios demográficos producto de esa actividad. Sobre la base de los resultados obtenidos se discuten alternativas para la evaluación del estado de las poblaciones locales del salmón de mar, y opciones de manejo para la pesca deportiva de altura sobre arrecifes rocosos. The Argentine sandperch Pseudopercis semifasciata (Cuvier, 1829) (Pinguipedidae) represents an important commercial and tourist resource in the northern Patagonian gulfs of Argentina. It inhabits low-relief rocky reefs known as “salmoneras”, which sustain recreational and commercial activities such as SCUBA diving and sport-, spear- and artisanal fishing. The Argentine sandperch is a vulnerable target to fishing due to its massive size (more than 1 m long and 20 kg weight), longevity (maximum age of about ~30 years) and low fecundity. However, its exploitation has never been regulated and conventional assessment and management approaches may not be applicable, depending on the migratory patterns and mobility of this species at different spatial scales. Information about spawning grounds and distribution of larvae and post-transition juveniles along the Argentine shelf was analyzed in order to investigate the possible occurrence of spawning migrations. The mobility and seasonal occupation of the reefs by different sizes, sexes and chromatic phenotypes of sandperch were studied at the local scale. A methodology was developed to estimate recreational angling effort and catches, and applied to data collected in San José Gulf over three fishing seasons. The demographic changes induced by fishing were also assessed. Possible approaches for the assessment of local sandperch populations and for the management of recreational angling on rocky reefs are suggested, based on the results obtained. Fil: Venerus, Leonardo Ariel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.

At least 18 taxa and "categories " of remains, mainly carbonised, were identified in the analysis of the non-wood plant macro-remains from the multi-phase Epipalaeolithic site of Öküzini (16560 ±180 uncal BP [18200-17400 cal ВС] to 12130 ±100 uncal BP [14400-11800 cal ВС]) and Karain В (ca 15000 uncal BP). The importance of plants in the diet and their role in determining patterns of mobility have been evaluated with quantitative and qualitative data. Nuts (principally Amygdalus, wild almond), fruits (principally Pyrus, wild pear), bulbs, roots or tubers seem to have occupied a particularly important place in these societies during all Epipalaeolithic phases, at the expense of small-seeded plants. The food plants attested in these samples would have provided carbohydrates, lipids and micronutrients, complementing meat in the diet. For the most part they were predictable and easy to gather and process. The almonds, rich in fats, could represent a vital seasonal resource that justified the additional work required for their detoxification. Judging from the seasonality indices of the plants and ungulate fauna at Öküzini, the cave could have been inhabited in all seasons periodically, but particularly in spring and autumn., Au moins 18 taxa et « catégories » de restes, pour la plupart carbonisés, ont été identifiés lors des analyses des macro-restes botaniques (charbons de bois exclus) du site Epipaléolithique multi-phase de Öküzini (16560 ±180 uncal BP [18200-17400 cal ВС] à 12130 ±100 uncal BP [14400-1 1 800 cal ВС]) et Karain В (env. 15000 uncal В P). L'importance et le rôle des plantes - en particulier dans l'alimentation et pour la détermination de la mobilité - ont été évalués à l'aide de données quantitatives et qualitatives. Les noix (principalement Amygdalus, amande sauvage) , fruits (essentiellement Pyrus, poire sauvage), bulbes, racines ou rhizomes semblent avoir occupé une place particulière dans ces sociétés pendant toutes les phases de l'Epipaléolithique, au détriment des plantes à petites graines. Les plantes alimentaires attestées fournissaient des hydrates de carbone, lipides et micronutriments complétant bien l'alimentation carnée et représentaient pour la plupart des ressources prédictibles, faciles à cueillir et à préparer. Les amandes, par leur richesse en graisse, pouvaient représenter une ressource saisonnière vitale, justifiant l 'addition de travail requis pour enlever leur toxicité. Selon les indices de saisonnalité des plantes et de la faune ongulée de Öküzini, la grotte pourrait en toutes saisons avoir été occupée de façon périodique mais plus particulièrement au printemps et en automne., Martinoli Danièle. Food plant use, temporal changes and site seasonality at Epipalaeolithic Öküzini and Karain B caves, southwest Anatolia, Turkey. In: Paléorient, 2004, vol. 30, n°2. pp. 61-80.

A mobile ad hoc network is a collection of wireless nodes, all of which may be mobile, that dynamically create a wireless network amongst them without using any infrastructure. Ad hoc wireless networks come into being solely by peer-to-peer interactions among their constituent mobile nodes, and it is only such interactions that are used to provide the necessary control and administrative functions supporting such networks. Mobile hosts are no longer just end systems; each node must be able to function as a router as well to relay packets generated by other nodes. As the nodes move in and out of range with respect to other nodes, including those that are operating as routers, the resulting topology changes must somehow be communicated to all other nodes as appropriate. In accommodating the communication needs of the user applications, the limited bandwidth of wireless channels and their generally hostile transmission characteristics impose additional constraints on how much administrative and control information may be exchanged, and how often. Ensuring effective routing is one of the greatest challenges for ad hoc networking. As a practice, ad hoc routing protocols make routing decisions based on individual node mobility even for applications such as disaster recovery, battlefield combat, conference room interactions, and collaborative computing etc. that are shown to follow a pattern. In this thesis we propose an algorithm that performs routing based on underlying mobility patterns. A mobility pattern aware routing algorithm is shown to have several distinct advantages such as: a more precise view of the entire network topology as the nodes move; a more precise view of the location of the individual nodes; ability to predict with reasonably accuracy the future locations of nodes; ability to switch over to an alternate route before a link is disrupted due to node movements. Master of Science