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This research aims to explain the influence of climatic variables (temperature and precipitation) in King George Island (KGI) glacier shrinkage on the Antarctic Peninsula. It employed Landsat satellite images from 1989 to 2020, climatic data and ONI index from 1980 to 2019. King George Island glaciers have lost 10% of their coverage in the last 31 years. Greater glacier shrinkage was shown until the first mid-period assessed, while the retreat rate slowed down for the second half of the studied period. Furthermore, of 73 KGI glaciers, 37% were marine- and landterminating, 42% were land-terminating and 21% were sea-terminating. Nonetheless, the decreases in the ice-coverage of marine-contact glaciers (35% of glacier coverage reduced) were higher than land-terminating glaciers (17% of glacier coverage reduced). There was a perceivable fluctuation in annual average air temperature for the 1980-2006 period. Nevertheless, from around 2007 to 2015/2016 there was a slight continuous cooling period and precipitation was somewhat above the average. Therefore, these patterns could explain the recent KGI glacier-retreat deceleration. Unlike the 1982/1983 and 1997/1998 El Niño events, the 2015/2016 El Niño was colder with precipitation reduction from the sustained annual amount (since roughly 2007 to 2015/2016) to values below the average. Moreover, during the 2015/2016 El Niño, KGI glacier coverage reduction was the lowest for the 31 year-long evaluated. However, it was revealed that the glacier's height could increase by accumulation in El Niño years, but glacier mass balance could be more negative due to basal melting. Additionally, land-terminating glaciers have lost more glacier coverage than sea-terminating glaciers throughout this ENSO event. Hence, climate variability might play a significant role in KGI glacier shrinkage, but calving process, glacier features and so on, further a combination of them should be assessed to reach a better understanding of KGI glacier retreat.

Along with air temperatures, the freezing level height (FLH) has risen over the last decades. The mass balance of tropical glaciers in Peru is highly sensitive to a rise in the FLH, mainly due to a decrease in accumulation and increase of energy for ablation caused by reduced albedo. Knowledge of future changes in the FLH is thus crucial to estimating changes in glacier extents. Since in situ data are scarce at altitudes where glaciers exist (above ~4800 m above sea level (asl)), reliable FLH estimates must be derived from multiple data types. Here we assessed the FLHs and their spatiotemporal variability, as well as the related snow/rain transition in the two largest glacier-covered regions in Peru by combining data from two climate reanalysis products, Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar Bright Band data, Micro Rain Radar data, and meteorological ground station measurements. The mean annual FLH lies at 4900 and 5010 m asl, for the Cordillera Blanca and Vilcanota, respectively. During the wet season, the FLH in the Cordillera Vilcanota lies ~150 m higher compared to the Cordillera Blanca, which is in line with the higher glacier terminus elevations. Coupled Model Intercomparison Project version 5 (CMIP5) climate model projections reveal that by the end of the 21st century, the FLH will rise by 230 m (±190 m) for Representative Concentration Pathway (RCP) 2.6 and 850 m (±390 m) for RCP8.5. Even under the most optimistic scenario, glaciers may continue shrinking considerably, assuming a close relation between FLH and glacier extents. Under the most pessimistic scenario, glaciers may only remain at the highest summits above approximately 5800 m asl. © 2017. American Geophysical Union. Por pares

Las crisis gelásticas son una forma rara de epilepsia no convulsiva, más frecuente en población adulta joven y casi exclusiva de hamartomas hipotalámicos; sin embargo, hay otras localizaciones no hipotalámicas poco descritas en las cuales se presentan estas crisis, como el lóbulo temporal. El caso que presentamos muestra una manifestación atípica: un paciente de edad avanzada consultó por cambios en el comportamiento y risas inmotivadas; durante la hospitalización, se estableció la presencia de crisis gelásticas, las cuales fueron atribuidas a zona de gliosis temporal izquierda por antecedente de hematoma epidural en esta localización. Se concluye que este tipo de crisis epiléptica en población de la tercera edad es el resultado de etiologías distintas al hamartoma hipotalámico. Gelastic seizures are a rare form of non-convulsive seizures, more common in young adults and almost exclusively of endocrine disorders and hypothalamic hamartomas, there another other places for this seizures as the temporal lobe. The case shows an atypical manifestation, an elderly patient who consults for changes in behavior and unmotivated laughter; during hospitalization, showed the presence of gelastic seizures, which were attributed to the left temporal area of gliosis by previous epidural hematoma at this location, we present clinical history, neuroimaging and EEG. In the conclusion on elderly, this type of seizure occurs by different etiologies and no only by hypothalamic hamartoma.

The hydrological data (since 1953) of the Llanganuco basin (87.0 km(2) 39% glacierized) show an increase of the glacial melting during the last quarter of the 20th century. These results were supplemented (since the end of 2000) by the data of the 2 small basin of Artesoncocha (8.4 km(2), 79% glacierized). The basin runoff is well correlated to the atmospheric temperature derived from the NOAA-NCEP re-analysis above the Cordillera Blanca. At the monthly time scale, the temperature is a good proxy of the glacier melting. The retreat of several glaciers in the Cordillera Blanca has been well documented for 50 years, highlighting an acceleration of the deglaciation in the mid-1970s. The use of these data of various origins permits one to model the behaviour of glaciers, especially the meltwater production, and then to predict their future evolution. The model was calibrated over the 1950-2000 period, thus providing a possible optimistic evolution range (underestimation if the climate change becomes more intense). The forcing of the model by forecasts of the future temperature evolution above the Cordillera Blanca, derived from the regionalization of global climatic models, allows improvement of the estimations only based on past glacial behaviour.

La temática tratada en el presente trabajo, apunta fundamentalmente hacia la comprobación argumentativa del desconocimiento del principio de interés general en el marco de la titularidad en los medios adjetivos o procedimentales que se desprenden según el ordenamiento jurídico colombiano, del proceso administrativo contractual público, en otras palabras de la legitimación en la causa en las acciones o medios de control judicial que proceden frente a la holística del contrato estatal. Dentro del presente contexto, puntualmente se ha fijado la atención en controvertir y replantear la titularidad operante frente al acto de adjudicación y la titularidad para controvertir el contrato estatal por nulidad absoluta. En este sentido, se ha procedido a desarrollar materias relacionadas con la teoría del Principio de Interés General; la descripción del estado actual de la titularidad en los medios de control judicial derivados del procedimiento administrativo contractual; se ha analizado desde la perspectiva del interés general, el modelo actual colombiano tratándose de la legitimación en la causa para el control de legalidad sobre la decisión de adjudicación contractual y la acción de controversias contractuales por nulidad absoluta y por último en una posición propositiva y prescriptiva, se ha esbozado el planteamiento de mecanismos judiciales deontológicos para la garantía del interés general, en el eficaz control de legalidad del acto administrativo de adjudicación contractual y el eficaz control del contrato estatal por nulidad absoluta. The subject dealt in this peace of work aims basically towards to verify the line of argument regarding the lack of knowledge in procedural means about the ownersip framework of the Colombian Judiciary System. The administrative contractual public process and the legitimation of the means of judiciary controls of Estate contracts. In the present context, the topic has been specially focused in discussing and reconsider the ownership against the allocation act as well as the discussion of Estate Contracts and their complete nulity. In this sense, it has been proceeded to develop subjects realated to the theory of “the General interest”, the description of the current state of ownership and the means of judiciary control product of the administrative contractual process. It has been analysed the point of view of the “general interest” in the current Colombian Model for the legal control of any contractual allocation and possible arguments and complete nullities. At last, it has been outlined an approach of ethical judiciary means in order to guarantee The “general interest” with the legal effective control of any contract of allocation as well as its possible complete nulity. Magister en Derecho Maestría