Memoria académica para optar al título de Periodista / El fenómeno del rock latino representa un hito excepcional dentro de los anales de la música contemporánea. Desde principios de la década de los ’80 y en medio de las dictaduras militares de Argentina y Chile se albergó un prolífico movimiento musical que rápidamente se extendió por el resto del continente. Si bien es cierto, en ambos países el proceso tiene características muy similares, es posible establecer como uno de los puntos primigenios, la censura impuesta en Argentina para la difusión de música en inglés debido a la Guerra de Las Malvinas (1982). A partir de ese momento y casi como un efecto dominó, el rock abre sus banderas de lucha ante el régimen político y desde Argentina irrumpe abruptamente en nuestro país, hacia 1984. Pero nuestra escena rockera no era una página en blanco. Ya existía un claro precedente musical de la mano del llamado “Canto Nuevo”, cuna de grandes figuras nacionales (Hugo Moraga, Eduardo Gatti, “Los Jaivas”, “Quilapayún”, etc.) y nuevos espacios de difusión (“Café del Cerro”, “Teatro Caupolicán, “Teatro Cariola”, etc). Asimismo, los rockeros nacionales tenían a sus principales exponentes en grupos como : “Tumulto”, “Arena Movediza”, “Millantún”, “Sol y Medianoche”, entre otros. Los medios de comunicación locales vivían un tiempo de censura y la radio, aparece como un bastión fundamental para la difusión de este semillero artístico. Surgen dos nombres importantes: Radio Chilena y Radio Galaxia. La primera de ellas difundió gran parte del material del Canto Nuevo, gracias al programa “Nuestro Canto”. La segunda, se convirtió en uno de los principales soportes del rock en español a través del programa “Hecho en Chile” , conducido por Sergio “Pirincho Cárcamo”. Frente a este espectro nacional, entre 1984 y 1985, Chile consume la producción discográfica de rock argentino correspondiente a cinco años. Llegan a nuestra palestra radial, nombres como : Charly García, Celeste Carballo, “Virus”, “Miguel Mateos”, “Los Enanitos Verdes”, “G.I.T.”, entre muchos otros. La camada rockera argentina aterrizó estrepitosamente apoderándose fuertemente de los gustos populares. En medio de aquella maraña musical, surge un nombre poderoso: “SODA STEREO”. Trío bonaerense que meteóricamente saltó a los primeros lugares cantando “Te hacen falta vitaminas” y “¿Por qué no puedo ser Jet?”, de su disco homónimo (1983).

This study attempts to explain changes in abundance of rock ptarmigan (Lagopus mutus) at Eagle Creek, Alaska. It includes an analysis of population data collected from 1960 to 1969, and a test of an hypothesis: that there were no differences in the quality (survival, growth, behaviour) of rock ptarmigan chicks between years that influenced spring densities. Spring densities fluctuated between 1960 and 1969, reaching peaks in 1962 and 1968. This was the result of an orderly and generally synchronous change in the loss of birds (primarily juveniles) in winter, accompanied by changes in the production of young. Both acted together in most years to either increase or decrease numbers. Each contributed approximately equally to changes in total annual loss. Changes in the production of young were primarily caused by parallel changes in both clutch sizes and nest failures. Population regulation by direct extrinsic control appeared unlikely. Other than weasel predation on nests, no environmental factor external to the population itself appeared sufficient to explain changes in winter loss of juveniles or clutch size loss, or their synchrony. These results suggested that some internal process within the population must have been important in changing the abundance of partmigan. I tested the aforementioned hypothesis in 1967, 1968, and 1969 by examining chicks both in the wild, and in captivity. Survival, growth, and behaviour of chicks all varied between years. Changes in survival were apparently determined by unidentified parental influences (genetic or physiological) rather than by the direct influence of the environment. Growth rates were similar between years in captivity, but not in the wild, suggesting that environmental influences must have had some effect. However, neither the changes in survival of chicks in summer, nor in growth rates, could be implicated in altering subsequent spring breeding densities. Levels of agonistic and aggressive behaviour in successive cohorts of aviary chicks differed. In the similar environment of the aviary each year, these behavioural changes were attributed to undetermined parental influences (genetic or physiological). These changes in aggressive-agonistic behaviour offer the best possible explanation of changes in the. population parameters most important in altering spring breeding densities. / Science, Faculty of / Zoology, Department of / Graduate

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A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy, Johannesburg, September 2017 / Rockburst occurrences and their consequent damage remain a problem in modern mining, particularly at great depth. The problem of rockbursts has also escalated in deepcivilengineeringtunnelsduetohighlevelsofin-situstressatsuchdepths. Key advancementshavebeenmadetodatetohelpmitigatethedrasticimpactscausedby rockburstdamage,withrocksupportremainingalineofdefensetoprovidestability in rockbursting situations. There is, however, an ongoing inability of support to contain severe rockburst damage, especially conventional support systems. More than two decades ago, a support concept termed “sacrificial support” was proposed as a potential additional method to help inhibit rockburst damage. The philosophy behind a sacrificial support system is that, under dynamic loading conditions, support, in the form of a liner must fail (i.e. be ejected from rock surface), leaving behind, undamaged, what was once supported rock mass. It is because of this reason that this support is referred to as a sacrificial support due to its ability to protect the rock from damage whilst the support itself fails. Since the inception of this support idea, it was only recently that the behaviour of support in real rockburst events manifested the sacrificial behaviour in rockbursting, which warranted the need for further research. The sacrificial support concept stated here is applicable in situations where the source (i.e. seismic event) of the rockburst is located remote from where rockburst damage is likely to occur. To investigate the behaviour of sacrificial support, controlled laboratory experimentsbasedonthesplitHopkinsonpressurebar(SHPB)techniquewereconducted to study some aspects of dynamic rock fracturing in tension at high strain rates, and also the role a sacrificial layer plays in combating dynamic rock failure (i.e. rockburst damage). To achieve this, a single Hopkinson pressure bar configured for spalling tests, comprised of a relatively long cylindrical intact rock specimen attached at the bar free end, was impacted by a striker on the opposite free end of the bar in order to generate a dynamic stress pulse responsible for spall failure upon reflection from the specimen free end. Different liners and/or liner combinations were then introduced at the specimen free end as sacrificial support. This experimental arrangement allowed the role of, and failure mechanisms associated with, sacrificial support under dynamic loading to be demonstrated, and comparisons were made with “sacrificial support” behaviour observed in real rockburst events in a mine. Analysis of experimental results revealed that varying liner thickness and mechanical impedance between rock and support liner plays a significant role in helping to limit rockburst damage. Apart from experimental investigations, numerical simulations were undertaken to further probe the behaviour of sacrificial support under dynamic loading. Elastic models subjected to p-wave propagation indicated failure of the sacrificial layer, manifested by ejection of the liner due to reflection of compressive wave at the free surface. This failure mechanism was noticed for all the liners, independent of variation in liner thickness, and wavelength characteristic of the applied wave to the model. The sacrificial support method presented in this thesis presents an opportunity to further enhance safety in seismically active mines. / XL2018

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M.Sc. (Geology) / The purpose of this work was to attempt to understand the behaviour of the ground around a series of holes bored in gold bearing rock by a reef boring machine. Furthermore this ground behaviour is compared with existing theoretical concepts of rock behaviour. The experimental boring site and the sequence of events at that site are described. The state of the rock surrounding the excavations is observed to deteriorate with increase in mining. The fracturing observed is characterised by spalling on the sides of the bored holes. This spalling increases in severity with closeness to the bored out region. Calculations of the stress acting on the sides of the bored holes were made from elastic theory using two techniques. One of these was a quick graphical technique and the other was a more complex analytical one. The analytical technique was used as a check on the results of the graphical technique. Finally the extent of spalling on the sides of the holes is compared with the theoretical stresses. A close correlation is found, and spalling appears to start when the stress level reaches the strength of the rock. As the stress level increases spalling increases in severity until such time as the ground around the bored area is fractured by large through going fractures. At this stage holes bored in this ground no longer spall.

Thesis (M.A.)--Cincinnati Christian Seminary, 1985. / Includes bibliographical references (leaf 182).

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presente estudo pretende analisar o Heavy Metal no Brasil nos anos 1980, historiando sua origem, bem como sua chegada ao Brasil e a forma como esse estilo foi absorvido pela juventude brasileira, destacando suas especificidades. Ao historiar esse processo, daremos ênfase ao panorama político, econômico e social do país no período e suas articulações com o movimento heavy metal, procurando responder até que ponto essas condições influenciaram a estética desse movimento, e como ele foi adaptado e absorvido no panorama cultural brasileiro, influenciando-o por sua vez / This study aims to analyze the Heavy Metal in Brazil in the 1980s studies the history their origin and their arrival in Brazil and how that style was absorbed by Brazilian youth, highlighting its specific features. When recounting this process, we will emphasize the political, economic and social landscape of the country in the period and its articulations with the heavy metal movement, seeking to respond to what extent these conditions influenced the aesthetics of this movement, and how it was adapted and absorbed into the cultural landscape Brazilian, influencing it in turn