34 resultados para Climber


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During glacial periods, atmospheric CO2 concentration increases and decreases by around 15 ppm. At the same time, the climate changes gradually in Antarctica. Such climate changes can be simulated in models when the AMOC (Atlantic Meridional Oceanic Circulation) is weakened by adding fresh water to the North Atlantic. The impact on the carbon cycle is less straightforward, and previous studies give opposite results. Because the models and the fresh water fluxes were different in these studies, it prevents any direct comparison and hinders finding whether the discrepancies arise from using different models or different fresh water fluxes. In this study we use the CLIMBER-2 coupled climate carbon model to explore the impact of different fresh water fluxes. In both preindustrial and glacial states, the addition of fresh water and the resulting slow-down of the AMOC lead to an uptake of carbon by the ocean and a release by the terrestrial biosphere. The duration, shape and amplitude of the fresh water flux all have an impact on the change of atmospheric CO2 because they modulate the change of the AMOC. The maximum CO2 change linearly depends on the time integral of the AMOC change. The different duration, amplitude, and shape of the fresh water flux cannot explain the opposite evolution of ocean and vegetation carbon inventory in different models. The different CO2 evolution thus depends on the AMOC response to the addition of fresh water and the resulting climatic change, which are both model dependent. In CLIMBER-2, the rise of CO2 recorded in ice cores during abrupt events can be simulated under glacial conditions, especially when the sinking of brines in the Southern Ocean is taken into account. The addition of fresh water in the Southern Hemisphere leads to a decline of CO2, contrary to the addition of fresh water in the Northern Hemisphere.

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∆14Catm has been estimated as 420 ± 80‰ (IntCal09) during the Last Glacial Maximum (LGM) compared to preindustrial times (0‰), but mechanisms explaining this difference are not yet resolved. ∆14Catm is a function of both cosmogenic production in the high atmosphere and of carbon cycling and partitioning in the Earth system. 10Be-based reconstructions show a contribution of the cosmogenic production term of only 200 ± 200‰ in the LGM. The remaining 220‰ have thus to be explained by changes in the carbon cycle. Recently, Bouttes et al. (2010, 2011) proposed to explain most of the difference in pCO2atm and δ13C between glacial and interglacial times as a result of brine-induced ocean stratification in the Southern Ocean. This mechanism involves the formation of very saline water masses that contribute to high carbon storage in the deep ocean. During glacial times, the sinking of brines is enhanced and more carbon is stored in the deep ocean, lowering pCO2atm. Moreover, the sinking of brines induces increased stratification in the Southern Ocean, which keeps the deep ocean well isolated from the surface. Such an isolated ocean reservoir would be characterized by a low ∆14C signature. Evidence of such 14C-depleted deep waters during the LGM has recently been found in the Southern Ocean (Skinner et al. 2010). The degassing of this carbon with low ∆14C would then reduce ∆14Catm throughout the deglaciation. We have further developed the CLIMBER-2 model to include a cosmogenic production of 14C as well as an interactive atmospheric 14C reservoir. We investigate the role of both the sinking of brine and cosmogenic production, alongside iron fertilization mechanisms, to explain changes in ∆14Catm during the last deglaciation. In our simulations, not only is the sinking of brine mechanism consistent with past ∆14C data, but it also explains most of the differences in pCO2atm and ∆14Catm between the LGM and preindustrial times. Finally, this study represents the first time to our knowledge that a model experiment explains glacial-interglacial differences in pCO2atm, δ13C, and ∆14C together with a coherent LGM climate.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The amazonian climber Gnetum venosum contains, besides the stilbenes resveratrol and rapontigentin (3-methoxyresveratrol), oxidative stilbene oligomers such as the dimer gnetin C and the trimers gnetin E, gnetin J (3''-hydroxygnetin E) and gnetin K (3''-methoxygnetin E). Gnetins J and K are described for the first time. Oligomers of stilbenoids constitute a new class of condensed tannins.

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The reproductive phenology of the entire climber community (96 species of lianas and 40 species of vines) in a semideciduous forest in Southeastern Brazil (22 degrees 49'45''S; 47 degrees 06'33''W and 670 m altitude) was observed from March 1988 to February 1991. Phenological observations were made weekly by walking along a 10.5 km trail in the interior and at the forest edges of the Santa Genebra Reserve (SGR). The most species-rich families of climbers were Bignoniaceae (22), Malpighiaceae (17), Sapindaceae (12) and Asteraceae (12). Flowering patterns for woody lianas and herbaceous vines differed. Lianas had two flowering peaks: a minor peak in March in the transition from wet to dry season, and a major peak in October during the transition from dry to wet season. The flowering peak for herbaceous vines was in April. Fruiting of lianas was highly seasonal, with one peak in the late dry season (July-August). Fruiting for vines was less seasonal with a slight peak in March. These differences were consistent with the predominance of wind-dispersed fruits among lianas (72% of species) versus vines (52%). Low rainfall, high leaf fall, and strong winds during the dry season favor wind dispersal. More species of vines (40%) have animal-dispersed seeds than lianas (19%), and most vines fruited during the wet season. Phenological patterns of climbers and trees and treelets at SGR differed. The life form of lianas and their system of reserve economy may allow them to reproduce during periods unfavorable to trees. Displacement of peak flowering periods of trees and climbers pollinated by bees and small generalist insects may decrease competition for pollen vectors among species of these two groups of plants. Whereas the fruiting patterns of wind-dispersed trees and climbers at SGR were similar (most species fruiting during the dry season), animal-dispersed trees and treelets fruited throughout the year while animal-dispersed climbers exhibited a pronounced peak in late wet season. The distinct phenological patterns of climbers, generally complementary to those presented by trees, resulted in constant availability of Bowers and fruits throughout the year and enhances the importance of this plant group in Neotropical forests.

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Camptosema grandiflorum Benth., belonging to Fabaceae, is a voluble climber plant native to Brazil. Plants bloom in autumn-winter, producing long and hanging inflorescences with showy red flowers, which are much visited by hummingbirds. The leaves are also attractive, composed by three leaflets. It can be propagated by seeds or cuttings, but both seed germination and cutting rooting percentages are very low. Thus, the objective of this work was to study the effect of different temperatures on seed germination and of different indolebutyric acid (IBA) concentrations on the rooting of cuttings of C. grandiflorum. The experiment was set up at the São Paulo State University, located in Jaboticabal, São Paulo State, Brazil. The germination study was conducted in an entirely randomized design with six different temperatures (constant at 20, 25, 30 and 35°C; and alternated at 20-30 and 25-35°C, with a photoperiod of 12 hours) and four replications of 25 seeds each, placed in plastic boxes with vermiculite. The percentage of germination and the speed germination index (SGI) were evaluated. An entirely randomized block design was adopted for the cutting rooting evaluation, with four IBA concentrations (0; 1,000; 2,000; and 3,000 mg kg-1) and five replications of ten cuttings each, comprising 200 cuttings. After 30 days from the beginning of the rooting experiment, data referring to rooting percentage, number and length of roots and dry weight of roots were collected. For the seed germination experiment, fastest germination and highest germination percentage (87%) were obtained when seeds were maintained under the constant temperature of 30°C. For the cutting experiment, the concentrations of 2,000 and 3,000 mg kg-1 of IBA promoted the highest rooting percentages (98.5 and 94.1%, respectively) and number of roots. There were no statistical differences among the IBA concentrations for length of roots and dry weight of roots.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Lianas can change forest dynamics, slowing down forest regeneration after a perturbation. In these cases, it may be necessary to manage these woody climbers. Our aim was to simulate two management strategies: (1) focusing on abundant liana species and (2) focusing on the largest lianas, and contrast them with the random removal of lianas. We applied mathematical simulations for liana removal in three different vegetation types in southeastern Brazil: a Rainforest, a Seasonal Tropical Forest, and a Woodland Savanna. Using these samples, we performed simulations based on two liana removal procedures and compared them with random removal. We also used regression analysis with quasi-Poisson distribution to test whether larger lianas were aggressive, i.e., if they climbed into many trees. The procedure of cutting larger lianas was as effective as cutting them randomly and proved not to be a good method for liana management. Moreover, most of the lianas climbed into one or two trees, i.e., were not aggressive. Cutting the most abundant lianas proved to be a more effective method than cutting lianas randomly. This method could maintain liana richness and presumably should accelerate forest regeneration.

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The growing interest in achieving the objectives of cycling policies has increased the need to know the key variables that influence the use of the bicycle for daily mobility. This paper makes a contribution in this research line by examining a varying nature of variables – objective and psychological - and their influence on cycling commuting in the context of a “climber cycling city”: Vitoria-Gasteiz (Spain). Statistical differences of the variables were determined between cycling commuters and commuters by other modes. The objective variables analyzed allowed us to identify the cycling commuting profile in Vitoria-Gasteiz, but showed a small effect on cycling commuting. However, analyses on seven cycling psychological variables identified and defined, showed a higher influence, especially “Individual capacities” and “Non-commuting cycling habit”. Their results allowed recommending a wide et of policy initiatives. These policy recommendations were made considering that Vitoria-Gasteiz is a “city in transition” towards cycling: a high level of cycling share for the Spanish contex t and the safety issue not being the main barrier for cycling. However the psychological latent variable “Non-commuting cycling habit” indicates that normalization of the bicycle as a mode of transport needs more progress.

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En la literatura se ha descrito el perfil antropométrico y la respuesta psicofisiológica en escalada deportiva en roca, pero hasta la fecha, no se habían analizado las diferencias existentes entre sus principales modalidades. El objetivo de la presente tesis fue describir las características antropométricas del escalador de competición y comprobar la existencia de diferencias entre los participantes de distintas modalidades, así como analizar la respuesta psico-fisiológica durante la ejecución de un búlder y una vía, además de evaluar las diferencias entre su realización a vista o tras un ensayo. Para ello, efectuamos dos estudios diferentes: en el primero participaron voluntariamente 61 hombres y 18 mujeres, participantes en cuatro pruebas del circuito nacional de competición de escalada durante el año 2009, tres de ellas de la modalidad de dificultad a vista y una de búlder. Se realizaron mediciones antropométricas, prueba de fuerza de prensión manual antes y después de competir, y se cumplimentó un cuestionario donde se evaluaba la percepción del esfuerzo y la experiencia deportiva. En el segundo estudio, 23 escaladores, 15 hombres y 8 mujeres, divididos en tres grupos en función de su nivel de rendimiento, realizaron de manera voluntaria distintas pruebas durante tres días separados entre sí al menos 48 horas. El primer día rellenaron un cuestionario sobre su experiencia deportiva y nivel de rendimiento, fueron pesados, tallados y sometidos a un escáner de cuerpo completo en densitómetro con objeto de medir la composición corporal. El segundo día realizaron previo calentamiento, un búlder a vista y, tras un descanso de 15 minutos, escalaron una vía a vista acorde con su nivel. El tercer día, después de calentar y disponer de 20 minutos para ensayarlo, repitieron la escalada del búlder. Tras un descanso de 15 minutos y 20 minutos de ensayo, realizaron un segundo intento a la vía. Se registraron los valores en la respuesta cardiorrespiratoria, se obtuvieron muestras de lactato en sangre del lóbulo de la oreja y se realizaron pruebas de fuerza de prensión manual antes y después de la escalada. También se pasó un cuestionario para medir la ansiedad y autoconfianza así como el esfuerzo percibido. Los resultados no mostraron diferencias antropométricas significativas entre los participantes en competiciones de búlder y los que participaron en competiciones de escalada de dificultad a vista. Se dieron diferencias en la pérdida de fuerza antes y después de escalar entre dichos participantes. Las mujeres obtuvieron menor fuerza de prensión manual que los hombres pero la misma pérdida de fuerza entre el instante antes de competir y el posterior. La respuesta fisiológica durante la ejecución del búlder fue menor que la obtenida durante la ejecución de la vía. Hubo pérdida de fuerza de prensión manual entre el instante anterior y el posterior a ejecutar la vía, pero no al hacer el búlder. Sin embargo, no se dieron diferencias en la ansiedad y la autoestima provocada por ambas modalidades, por lo que deducimos que la ejecución de un búlder y una vía presentan una respuesta fisiológica distinta. Proponemos que la respuesta está relacionada, sobre todo, con las variables de ejecución, de tal manera que a mayor distancia y/o tiempo recorrido en la escalada, mayor será la contribución anaeróbica al esfuerzo y la fatiga manifestada como pérdida de fuerza que, en el caso del búlder, fue mínima o inexistente. En el segundo intento, tras un ensayo de 20 minutos en el búlder, se consiguió mejorar el rendimiento respecto al primer intento, que se manifestó con un aumento en la distancia recorrida. Sin embargo, en la vía no se dieron diferencias entre ambos intentos, ni en la ejecución, ni en la respuesta fisiológica, ni en la ansiedad, ni siquiera en la fuerza de prensión manual. ABSTRACT It has been described in the literature the anthropometric profile and psychophysiological response in rock climbing, but so far not been analyzed differences between its main modalities. The aim of this thesis was to describe the anthropometric characteristics of the climber competitor and check for differences between participants of different modalities and to analyze the psycho-physiological response during the execution of a boulder and a route also to assess differences between on sight and redpoint attempts. We made two different studies: in the first 61 men and 18 women who attended four competitions of national climbing circuit in 2009, three of them on-sight difficulty competitions and a boulder competition participated voluntarily. Anthropometric measurements, a hand grip strength test before and after competing were registered for each climber, and a questionnaire which assessed perception of effort and the climbing experience was fulfilled. In the second study, various tests were conducted on 23 volunteer climbers, 15 men and 8 women, during three days separated for, at least, 48 hours of resting, divided into three groups according to their performance. The first day, climbers completed a questionnaire on their experience and performance level. It was recorded weight, height and they underwent a full body scan densitometer in order to measure body composition. The second day, after previous warming-up, they climbed a boulder on sight and, after a break of 15 minutes, climbed a route on-sight according to their level. The third day, after warming-up and have 20 minutes to try it, they repeated the bouldering climbing. After a break of 15 minutes and 20 minutes of essaying, they made a second attempt at the route. Values in the cardiorespiratory response were recorded, blood lactate samples were obtained from earlobe, and hand grip strength was tested before and after the climb. They also filled a questionnaire to measure anxiety and self-confidence and perceived exertion. The results showed no significant anthropometric differences between participants in bouldering competitions and participants in competitions on-sight difficulty climbing. There were found differences in strength loss before and after climbing between those participants. Women had less hand grip strength than men but the same loss of strength between the records carried out before and after competing. The physiological response recorded for boulder climbing was lower than the obtained for the route. There was loss of hand grip strength between the time before and after running the route but not for bouldering. However, there were no differences in anxiety and self-esteem caused by both modalities, so we conclude that the implementation of a boulder and a route have different physiological responses. We think that this response is mainly related to performance variables, as a greater distance and/or travel time on the climb, the higher the anaerobic contribution to the effort and fatigue as manifested by loss of strength in the case of the boulder was minimal or nonexistent. In the second attempt after 20 minutes in the boulder better performance was achieved on the first attempt, which was manifested by an increment of climbing distance. However, there were the differences in the route between the two attempts, either in execution or in the physiological response, or anxiety, or even in hand grip strength.

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El autor de este proyecto es miembro reciente de la asociación SoloBoulder, dedicada a la modalidad de escalada boulder, noticias y actualidad, contenido multimedia, promoción de un equipo de escaladores y defensa de valores medioambientales en la montaña. El principal canal de distribución de contenidos es una página web existente previa a este proyecto. La asociación ha detectado una escasez y mala calidad de recursos en internet en cuanto a guías de zonas donde poder practicar el boulder. Tal circunstancia impulsa la iniciativa de este proyecto fin de carrera. El objetivo general es el desarrollo de una nueva aplicación que proporcione a los usuarios a nivel mundial una guía interactiva de boulder y otros puntos de interés, una red social que permita la creación cooperativa y orgánica de contenido, y servicios web para el consumo de la información desde otras plataformas u organizaciones. El nuevo software desarrollado es independiente de la página web de SoloBoulder previa. No obstante, ambas partes se integran bajo el mismo domino web y aspecto. La nueva aplicación ofrece a escaladores y turistas un servicio informativo e interactivo de calidad, con el que se espera aumentar el número de visitas en todo el sitio web y poder ampliar la difusión de valores medioambientales, diversificar las zonas de boulder y regular las masificadas, favorecer el deporte y brindar al escalador una oportunidad de autopromoción personal. Una gran motivación para el autor también es el proceso de investigación y formación en tecnologías, patrones arquitecturales de diseño y metodologías de trabajo adaptadas a las tendencias actuales en la ingeniería de software, con especial curiosidad hacia el mundo web. A este respecto podemos destacar: metodología de trabajo en proyectos, análisis de proyectos, arquitecturas de software, diseño de software, bases de datos, programación y buenas prácticas, seguridad, interfaz gráfica web, diseño gráfico, Web Performance Optimization, Search Engine Optimization, etc. En resumen, este proyecto constituye un aprendizaje y puesta en práctica de diversos conocimientos adquiridos durante la ejecución del mismo, así como afianzamiento de materias estudiadas en la carrera. Además, el producto desarrollado ofrece un servicio de calidad a los usuarios y favorece el deporte y la autopromoción del escalador. ABSTRACT. The author of this Project is recent member of the association SoloBoulder, dedicated to a rock climbing discipline called bouldering, news, multimedia content, promotion of a team of climbers and defense of environmental values in the mountain. The main content distribution channel is a web page existing previous to this project. The association has detected scarcity and bad quality of resources on the internet about guides of bouldering areas. This circumstance motivates the initiative of this project. The general objective is the development of a new application which provides a worldwide, interactive bouldering guide, including other points of interest, a social network which allows the cooperative and organic creation of content, and web services for consumption of information from other platforms or organizations. The new software developed is independent of the previous SoloBoulder web page. However, both parts are integrated under the same domain and appearance. The new application offers to climbers and tourists a quality informative and interactive service, with which we hope to increase the number of visits in the whole web site and be able to expand the dissemination of environmental values, diversify boulder areas and regulate the overcrowded ones, encourage sport and offer to the climber an opportunity of self-promotion. A strong motivation for the author is also the process of investigation and education in technologies, architectural design patterns and working methodologies adapted to the actual trends in software engineering, with special curiosity about the web world. In this regard we could highlight: project working methodologies, project analysis, software architectures, software design, data bases, programming and good practices, security, graphic web interface, graphic design, Web Performance Optimization, Search Engine Optimization, etc. To sum up, this project constitutes learning and practice of diverse knowledge acquired during its execution, as well as consolidation of subjects studied in the degree. In addition, the product developed offers a quality service to the users and favors the sport and the selfpromotion of the climber.

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Using the coupled climate model CLIMBER-3α, we investigate changes in sea surface elevation due to a weakening of the thermohaline circulation (THC). In addition to a global sea level rise due to a warming of the deep sea, this leads to a regional dynamic sea level change which follows quasi-instantaneously any change in the ocean circulation. We show that the magnitude of this dynamic effect can locally reach up to ~1m, depending on the initial THC strength. In some regions the rate of change can be up to 20-25 mm/yr. The emerging patterns are discussed with respect to the oceanic circulation changes. Most prominent is a south-north gradient reflecting the changes in geostrophic surface currents. Our results suggest that an analysis of observed sea level change patterns could be useful for monitoring the THC strength.

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The cold climate anomaly about 8200 years ago is investigated with CLIMBER-2, a coupled atmosphere-ocean-biosphere model of intermediate complexity. This climate model simulates a cooling of about 3.6 K over the North Atlantic induced by a meltwater pulse from Lake Agassiz routed through the Hudson strait. The meltwater pulse is assumed to have a volume of 1.6 x 10^14 m^3 and a period of discharge of 2 years on the basis of glaciological modeling of the decay of the Laurentide Ice Sheet ( LIS). We present a possible mechanism which can explain the centennial duration of the 8.2 ka cold event. The mechanism is related to the existence of an additional equilibrium climate state with reduced North Atlantic Deep Water (NADW) formation and a southward shift of the NADW formation area. Hints at the additional climate state were obtained from the largely varying duration of the pulse-induced cold episode in response to overlaid random freshwater fluctuations in Monte Carlo simulations. The model equilibrium state was attained by releasing a weak multicentury freshwater flux through the St. Lawrence pathway completed by the meltwater pulse. The existence of such a climate mode appears essential for reproducing climate anomalies in close agreement with paleoclimatic reconstructions of the 8.2 ka event. The results furthermore suggest that the temporal evolution of the cold event was partly a matter of chance.

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Taking risk with all the consequences inevitably belongs to climbing. Each climber confronts his or her skills with the route he or she has chosen for an ascent. If the route is well protected, the rate of risk the climber takes is lower. If the route is less protected, the level of risk that the climber is exposed to proportionally increases. The aim of the research is to determine the level of risk-taking in traditional climbing on sandstone. We focus on how the level of risk affects climber’s performance and what reserve a climber needs to be able to cope with the higher risk and reduce it? The problem is solved by methods of quantitative research and the sample comprises more than 300 respondents. The results of the research prove a significant difference of climbers’ performance in dependence on rate of risk. Climbers usually reach lower performance according to the grading scale when climbing traditional routes with a higher level of risk.

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Ser.1, v.2-15 "Par M. L. Climber et F. Danjou"; ser.2, v.1-2 "Par F. Danjou et M. L. Climber"; v.3-12 "Par F. Danjou.