970 resultados para STAR-FORMATION HISTORY


Relevância:

20.00% 20.00%

Publicador:

Resumo:

In previous Analytical Electron Microscope studies of extraterrestrial Chondritic Porous Aggregate (CPA) W7029* A, we have reported on the presence of layer silicates(Rietmeijer and Mackinnon, 1984a; Mackinnon and Rietmeijer, 1983) and metal oxides (Rietmeijer and Mackinnon, 1984a; Mackinnon and Rietmeijer, 1984). We present here a continuation ofthis detailed mineralogical study and propose a scenario which may account for the variety and types of phases observed in this CPA. At least 50% ofCPA W7029*A is carbonaceous material, primarily poorly graphitised carbon (POC) with morphologies similar to POC in acid residues of carbonaceous chondrites (Smith and Busek, 1981; Lumpkin, 1983). The basal spacing of graphite in CPA W7029*A ranges from 3.47-3.52 A and compares with doo, of graphite in the Allende residues (Smith and Buseck, 1981; Lumpkin, 1983). Low-temperature phases comprise - 20% of CPA W7029*A and include layer silicates, Bi,O" a-FeOOH(Rietmeijer and Mackinnon, 1984a; Mackinnon and Rietmeijer, 1983), BaSO.,.Ti.O, plates, pentlandite-violarite and bornite. Clusters of Mg-rich olivine and pyroxene make up - 12% of the aggregate...

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Courtney Pedersen and Charles Robb's A Natural History of Trees was a installation mounted at Blindside ARI in Melbourne's CBD in 2012. The work took the form of a pine-panelled room containing a pair of life-sized tree trunks composed entirely of stacks of cut paper discs. A faux bois stool reinforced the sense of artificiality. Claustrophic and precarious, the installation was simultaneously a response to the complexity of our relationship with nature and place, and an evocation of the precarious quality of the collaborative process. The exhibition was accompanied by a catalogue with an essay by writer/curator, Jane O'Neill.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Words and Silences is the official on-line journal of the International Oral History Association. It is an internationally peer reviewed, high quality forum for oral historians from a wide range of disciplines and a means for the professional community to share projects and current trends of oral history from around the world. We are extremely pleased to release the first online issue of Word &Silences. This e-journal is the result of long standing discussion and debate about the best way to publish a quality bilingual oral history journal (including a blind peer reviewed section) as a viable solution to mounting difficulties associated with publishing in print. We have discovered that an online version is also not without its challenges and requires tremendous labor intensive dedication. We strongly encourage members to assist us with small review process tasks in the future, so that we can ensure the sustainability of an annual W&S publication for our members and beyond.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

High tumor kallikrein-related-peptidase 4 (KLK4) levels are associated with a poor outcome for women with serous epithelial ovarian cancer (EOC), for which peritoneal dissemination and chemoresistance are key events. To determine the role of KLK4 in these events, we examined KLK4-transfected SKOV-3 and endogenous KLK4 expressing OVCA432 cells in 3-dimensional (3D) suspension culture to mimic the ascites microenvironment. KLK4-SKOV-3 cells formed multicellular aggregates (MCAs) as seen in ascites, as did SKOV-3 cells treated with active KLK4. MCA formation was reduced by treatment with a KLK4 blocking antibody or the selective active site KLK4 sunflower trypsin inhibitor (SFTI-FCQR). KLK4-MCAs formed larger cancer cell foci in mesothelial cell monolayers than those formed by vector and native SKOV-3 cells, suggesting KLK4-MCAs are highly invasive in the peritoneal microenvironment. A high level of KLK4 is expressed by ascitic EOC cells compared to matched primary tumor cells, further supporting its role in the ascitic microenvironment. Interestingly, KLK4 transfected SKOV-3 cells expressed high levels of the KLK4 substrate, urokinase plasminogen activator (uPA), particularly in 3D-suspension, and high levels of both KLK4 and uPA were observed in patient cells taken from ascites. Importantly, the KLK4-MCAs were paclitaxel resistant which was reversed by SFTI-FCQR and to a lesser degree by the general serine protease inhibitor, Aprotinin, suggesting that in addition to uPA, other as yet unidentified substrates of KLK4 must be involved. Nonetheless, these data suggest that KLK4 inhibition, in conjunction with paclitaxel, may improve the outcome for women with serous epithelial ovarian cancer and high KLK4 levels in their tumors.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This thesis examines online spoof videos in China. It shows the relationship between user-created content and change and how such videos are impacting on social memory. In the West, we are witnessing two outstanding trends in media. On the one hand, media are turning more "demotic" (Turner, 2006) and "participatory" (Jenkins, 2006), whereby lay audiences use popular media for identity formation, representation and association, reconfiguring the media and cultural landscape, and rendering invalid the old paradigm based on the dichotomy of audience and author, creator and consumer, expert and amateur. On the other hand, in both mainstream media and user-creation online there is a trend towards "silly citizenship", with comedy, send-ups and spoofs that used to reside in the margin propelled to the central stage in both pleasure and politics (Hartley, 2010), as is shown in the rising popularity of the Daily Show, Colbert Report, and spoof videos in elections ,e.g. the 2008 presidential election in US (Gray, Jones, & Thompson, 2009; Tryon, 2008). User generated content—and spoof subcultures—is now much a debated phenomenon in China. However, with different political (one party rule and censorship) and cultural (media regarded mainly as instrument for education and social stabilization instead of a critical fourth estate) configurations, will the social and cultural impacts of the two trends in the West be as the same in China? If not, what will be the specificities in the China context? The project starts with a historical review of popular culture and user-created content in China, before turning to spoof videos and looking at how they are produced and shared, travel and diffused on the Internet, and how the communities and sub-cultures forming and emerging around spoof videos are changing the overall cultural landscape in China. By acting as a participant observer in online video sharing sites and conducting face-to face as well as online interviews, I identify lead users and creators of spoof videos and the social networks emerging around them. I call these lead users "skill hubs" and their networks "liquid communities", foregrounding the fact that their appeal doesn’t come from their amicable personality, but rather from their creative skills; and that the networks surrounding them are in a permanent flux, with members coming and going as they see fit. I argue that the "liquidness" (Bauman, 2000) of these communities is what makes them constantly creative and appealing. Textual analysis of online videos, their comments and derivatives are conducted to tease out the uses that that can be made of spoof videos, namely as phatic communication, as alternative memory and as political engagement. Through these analyses I show that spoof videos constitute not only a space where young generations can engage with each other, communicate their anger and dissatisfaction, fun and hope, and where they participate in socio-cultural and political debates, but also create a space where they can experiment with their new skills, new ideas, and new citizenship. The rise of spoof videos heralds the beginning of a trend in popular culture in contemporary China towards the "canonization of the jester" and the dethroning of the establishment. I also argue that a historical perspective is needed to understand the current surge of use creativity and user activism in China, and that many forms of popular media we experience today have their antecedents in various stages of Chinese history. The entrenched "control-resistance" binary is inadequate in interpreting the rich, flux and multilayered Internet space in China.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In 2011 Queensland suffered both floods and cyclones, leaving residents without homes and their communities in ruins (2011). This paper presents how researchers from QUT, who are also members of the Oral History Association of Australia (OHAA) Queensland’s chapter, are using oral history, photographs, videography and digital storytelling to help heal and empower rural communities around the state and how evaluation has become a key element of our research. QUT researchers ran storytelling workshops in the capital city of Brisbane i early 2011, after the city suffered sever flooding. Cyclone Yasi then struck the town of Cardwell (in February 2011) destroying their historical museum and recording equipment. We delivered an 'emergency workshop', offering participants hands on use of the equipment, ethical and interviewing theory, so that the community could start to build a new collection. We included oral history workshops as well as sessions on how best to use a video camera, digital camera and creative writing sessions, so the community would also know how to make 'products' or exhibition pieces out of the interviews they were recording. We returned six months later to conduct follow-up workshops and the material produced by and with the community had been amazing. More funding has now been secured to replicate audio/visual/writing workshops in other remote rural Queensland communities including Townsville, Mackay and Cunnamulla and Toowoomba in 2012, highlighting the need for a multi media approach, to leverage the most out of OH interviews as a mechanism to restore and promote community resilience and pride.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Detailed mineralogical studies of the matrix and fracture-fill materials of a large number of samples from the Rustler Formation have been carried out using x-ray diffraction, high-resolution transmission electron microscopy, electron microprobe analysis, x-ray fluorescence, and atomic absorption spectrophotometry. These analyses indicate the presence of four clay minerals: interstratified chlorite/saponite, illite, chlorite, and serpentine. Corrensite (regularly stratified chlorite/saponite) is the dominant clay mineral in samples from the Culebra dolomite and two shale layers of the lower unnamed member of the Rustler Formation. Within other layers of the Rustler Formation, disordered mixed chlorite/saponite is usually the most abundant clay mineral. Studies of the morphology and composition of clay crystallites suggest that the corrensite was formed by the alteration of detrital dioctahedral smectite in magnesium-rich pore fluids during early diagenesis of the Rustler Formation. This study provides initial estimates of the abundance and nature of the clay minerals in the Culebra dolomite in the vicinity of the Waste Isolation Pilot Plant.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Michel Foucault: The unconscious of history and culture The French thinker, Michel Foucault (1926–84), is noted for his extensive and controversial forays into the historical disciplines. When his work first began to circulate in the 1950s and 1960s, historians did not quite know what to make of it and philosophers resented the appearance of what they saw as the importation of the tedium of concrete events into the pure untainted realm of ideas. If these responses to his work remain alive and well decades after Foucault's death, the uptake of his work has become far more complex. To restrict ourselves to the discipline of history here: if one very visible and vocal camp of historians remains deeply ambivalent about his work, this merely disguises the fact that a far larger contingent of historians of all kinds – not just those located in history departments – use his ideas quite unremarkably ...

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This series of research vignettes is aimed at sharing current and interesting research findings from our team of international Entrepreneurship researchers. This vignette, written by Mr. Darren Kavanagh and Professor Per Davidsson, takes a closer look at job creation by new firms.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Large Igneous Provinces are exceptional intraplate igneous events throughout Earth’s history. Their significance and potential global impact is related to the total volume of magma intruded and released during these geologically brief events (peak eruptions are often within 1-5 Myrs duration) where millions to tens of millions of cubic kilometers of magma are produced. In some cases, at least 1% of the Earth’s surface has been directly covered in volcanic rock, being equivalent to the size of small continents with comparable crustal thicknesses. Large Igneous Provinces are thus important, albeit episodic episodes of new crust addition. However, most magmatism is basaltic so that contributions to crustal growth will not always be picked up in zircon geochronology studies that better trace major episodes of extension-related silicic magmatism and the silicic Large Igneous Provinces. Much headway has been made on our understanding of these anomalous igneous events over the last 25 years, driving many new ideas and models. This includes their: 1) global spatial and temporal distribution, with a long-term average of one event approximately every 20 Myrs, but a clear clustering of events at times of supercontinent break-up – Large Igneous Provinces are thus an integral part of the Wilson cycle and are becoming an increasingly important tool in reconnecting dispersed continental fragments; 2) compositional diversity that in part reflects their crustal setting of ocean basins, and continental interiors and margins where in the latter setting, LIP magmatism can be silicicdominant; 3) mineral and energy resources with major PGE and precious metal resources being hosted in these provinces, as well as magmatism impacting on the hydrocarbon potential of volcanic basins and rifted margins through enhancing source rock maturation, providing fluid migration pathways, and trap formation; 4) biospheric, hydrospheric and atmospheric impacts, with Large Igneous Provinces now widely regarded as a key trigger mechanism for mass extinctions, although the exact kill mechanism(s) are still being resolved; 5) role in mantle geodynamics and thermal evolution of the Earth, by potentially recording the transport of material from the lower mantle or core-mantle boundary to the Earth's surface and being a fundamental component in whole mantle convection models; and 6) recognition on the inner planets where the lack of plate tectonics and erosional processes and planetary antiquity means that the very earliest record of LIP events during planetary evolution may be better preserved than on Earth.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A novel multiple regression method (RM) is developed to predict identity-by-descent probabilities at a locus L (IBDL), among individuals without pedigree, given information on surrounding markers and population history. These IBDL probabilities are a function of the increase in linkage disequilibrium (LD) generated by drift in a homogeneous population over generations. Three parameters are sufficient to describe population history: effective population size (Ne), number of generations since foundation (T), and marker allele frequencies among founders (p). IBD L are used in a simulation study to map a quantitative trait locus (QTL) via variance component estimation. RM is compared to a coalescent method (CM) in terms of power and robustness of QTL detection. Differences between RM and CM are small but significant. For example, RM is more powerful than CM in dioecious populations, but not in monoecious populations. Moreover, RM is more robust than CM when marker phases are unknown or when there is complete LD among founders or Ne is wrong, and less robust when p is wrong. CM utilises all marker haplotype information, whereas RM utilises information contained in each individual marker and all possible marker pairs but not in higher order interactions. RM consists of a family of models encompassing four different population structures, and two ways of using marker information, which contrasts with the single model that must cater for all possible evolutionary scenarios in CM.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A wide variety of experiments that involve the physics of small particles (μm to cm in size) of planetary significance can be conducted on the Space Station. Processes of interest include nucleation and condensation of particles from a gas, aggregation of small particles into larger ones, and low velocity collisions of particles. Only experiments relevant to planetary processes will be discussed in detail here.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The interaction of bare graphene nanoribbons (GNRs) was investigated by ab initio density functional theory calculations with both the local density approximation (LDA) and the generalized gradient approximation (GGA). Remarkably, two bare 8-GNRs with zigzag-shaped edges are predicted to form an (8, 8) armchair single-wall carbon nanotube (SWCNT) without any obvious activation barrier. The formation of a (10, 0) zigzag SWCNT from two bare 10-GNRs with armchair-shaped edges has activation barriers of 0.23 and 0.61 eV for using the LDA and the revised PBE exchange correlation functional, respectively, Our results suggest a possible route to control the growth of specific types SWCNT via the interaction of GNRs.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Modern and Postmodern Los Angeles is examined through the lens of film noir and neo noir. The unique relationship between the city of Los Angeles and cinema is discussed in terms of a historiography emphasizing the role played by these defining film styles and genres. The research draws and extends on the work conducted by Edward Dimendberg, Paula Rabinowitz and Mike Davis, and urban theory approaches associated with the Los Angeles School of Urbanism.