49 resultados para Arbre de recombinaison ancestral (ARG)
em Queensland University of Technology - ePrints Archive
Resumo:
An experiment in large scale, live, game design and public performance, bringing together participants from across the creative arts to design, deliver and document a project that was both a cooperative learning experience and an experimental public performance. The four month project, funded by the Edge Digital Centre, culminated into a 24 hour ARG event involving over 100 participants in December 2012. Using the premise of a viral outbreak, young enthusiasts auditioned for the roles of Survivor, Zombie, Medic and Military. The main objective was for the Survivors to complete a series of challenges over 24 hours, while the other characters fulfilled their opposing objectives of interference and sabotage supported by both scripted and free-form scenarios staged in constructed scenes throughout the venues. The event was set in the State Library of Queensland and the Edge Digital Centre who granted the project full access, night and day to all areas including public, office and underground areas. These venues were transformed into cinematic settings full of interactive props and various audio-visual effects. The ZomPoc Project was an innovative experiment in writing and directing a large scale, live, public performance, bringing together participants from across the creative industries. In order to design such an event a number of innovative resources were developed exploiting techniques of game design, theatre, film, television and tangible media production. A series of workshops invited local artists, scientists, technicians and engineers to find new ways of collaborating to create networked artifacts, experimental digital works, robotic props, modular set designs, sound effects and unique costuming guided by an innovative multi-platform script developed by Deb Polson. The result of this collaboration was the creation of innovative game and set props, both atmospheric and interactive. Such works animated the space, presented story clues and facilitated interactions between strangers who found themselves sharing a unique experience in unexpected places.
Resumo:
BACKGROUND: The increasing number of assembled mammalian genomes makes it possible to compare genome organisation across mammalian lineages and reconstruct chromosomes of the ancestral marsupial and therian (marsupial and eutherian) mammals. However, the reconstruction of ancestral genomes requires genome assemblies to be anchored to chromosomes. The recently sequenced tammar wallaby (Macropus eugenii) genome was assembled into over 300,000 contigs. We previously devised an efficient strategy for mapping large evolutionarily conserved blocks in non-model mammals, and applied this to determine the arrangement of conserved blocks on all wallaby chromosomes, thereby permitting comparative maps to be constructed and resolve the long debated issue between a 2n=14 and 2n=22 ancestral marsupial karyotype. RESULTS: We identified large blocks of genes conserved between human and opossum, and mapped genes corresponding to the ends of these blocks by fluorescence in situ hybridization (FISH). A total of 242 genes was assigned to wallaby chromosomes in the present study, bringing the total number of genes mapped to 554 and making it the most densely cytogenetically mapped marsupial genome. We used these gene assignments to construct comparative maps between wallaby and opossum, which uncovered many intrachromosomal rearrangements, particularly for genes found on wallaby chromosomes X and 3. Expanding comparisons to include chicken and human permitted the putative ancestral marsupial (2n=14) and therian mammal (2n=19) karyotypes to be reconstructed. CONCLUSIONS: Our physical mapping data for the tammar wallaby has uncovered the events shaping marsupial genomes and enabled us to predict the ancestral marsupial karyotype, supporting a 2n=14 ancestor. Futhermore, our predicted therian ancestral karyotype has helped to understand the evolution of the ancestral eutherian genome.
Resumo:
A review of A History of Silence by Lloyd Jones (Text Publishing, 2013).
Resumo:
Poetry expresses the physical and spiritual worlds that other kinds of writing cannot. Travelling open our minds and frees our spirit. Creative writings and meditations on life, spirit, grace and relationships, art and nature weave their way through these lyrical poems. Some poems are suitable for study in the Australian Curriculum.
Resumo:
In the album Journey, Archie Roach -- the Australian Indigenous singer-songwriter hailing from Mooroopna in Victoria - has a melancholy song called ‘Travell’n Bones.' It is about the repatriation of Indigenous ancestral remains to their rightful home. This Chapter considers the legal, ethical, and cultural conflicts over Australian indigenous remains being held in museums, in Australia, the United Kingdom, the European Union, and the United States. James Nason comments: ‘The explosion of legal and extra legal attention on issues of cultural property and heritage was born of the frustration and anger of indigenous peoples whose rights and perspectives about cultural property and heritage issues had been largely absent and essentially unwanted by the museum of community.' Part I focuses upon disputes in Australia involving the repatriation of Indigenous Australian remains. In Bropho v HREOC, there was controversy over a cartoon, mocking the repatriation of the remains of Yagan, an Indigenous warrior, to Western Australia. There was a discussion about the operation of the Racial Discrimination Act 1975 (Cth), and the exemptions available from the operation of the regime. Part II considers the efforts by The Te Papa Tongarewa - the Museum of New Zealand - to repatriate Maori and Moriori ancestral remains to New Zealand, and to iwi communities of origin. The conclusion considers the relevance of the United Nations Declaration on the Rights of Indigenous Persons 2007, and issues raised by ventures such as the Genographic Project.
Resumo:
Investigation of 31 of Roma patients with congenital lactic acidosis (CLA) from Bulgaria identified homozygosity for the R446* mutation in the PDHX gene as the most common cause of the disorder in this ethnic group. It accounted for around 60% of patients in the study and over 25% of all CLA cases referred to the National Genetic Laboratory in Bulgaria. The detection of a homozygous patient from Hungary and carriers among population controls from Romania and Slovakia suggests a wide spread of the mutation in the European Roma population. The clinical phenotype of the twenty R446* homozygotes was relatively homogeneous, with lactic acidosis crisis in the first days or months of life as the most common initial presentation (15/20 patients) and delayed psychomotor development and/or seizures in infancy as the leading manifestations in a smaller group (5/20 patients). The subsequent clinical picture was dominated by impaired physical growth and a very consistent pattern of static cerebral palsy-like encephalopathy with spasticity and severe to profound mental retardation seen in over 80% of cases. Most patients had a positive family history. We propose testing for the R446* mutation in PDHX as a rapid first screening in Roma infants with metabolic acidosis. It will facilitate and accelerate diagnosis in a large proportion of cases, allow early rehabilitation to alleviate the chronic clinical course, and prevent further affected births in high-risk families.
Resumo:
Denaturation of extracellular matrix proteins exposes cryptic binding sites. It is hypothesized that binding of cell adhesion receptors to these cryptic binding sites regulates cellular behaviour during tissue repair and regeneration. To test this hypothesis, we quantify the adhesion of pre-osteoblastic cells to native (Col) and partially-denatured (pdCol) collagen I using single-cell force spectroscopy. During early stages of cell attachment (≤180 s) pre-osteoblasts (MC3T3-E1) adhered significantly stronger to pdCol compared to Col. RGD (Arg-Gly-Asp)-containing peptides suppressed this elevated cell adhesion. We show that the RGD-binding α5β1- and αv-integrins mediated pre-osteoblast adhesion to pdCol, but not to Col. On pdCol pre-osteoblasts had a higher focal adhesion kinase tyrosine-phosphorylation level that correlated with enhanced spreading and motility. Moreover, pre-osteoblasts cultured on pdCol showed a pronounced matrix mineralization activity. Our data suggest that partially-denatured collagen exposes RGD-motifs that trigger binding of α5β1- and αv-integrins. These integrins initiate cellular processes that stimulate osteoblast adhesion, spreading, motility and differentiation. Taken together, these quantitative insights reveal an approach for the development of alternative collagen I- based surfaces for tissue engineering applications.
Resumo:
An Alternate Reality Game (ARG) is a unique experience that blurs the edges between our everyday lives and imagined game worlds. Players are invited to interact with each other and fictional characters using familiar tools such as emails, websites, telephones, and sometimes newspapers, radio and television. ARGs come in all shapes and sizes, tell a variety of different stories and inspire all kinds of interactions between people, their networks and the very streets in which they live. Some ARGs simply immerse you in fictional scenarios and indulge you in quirky challenges. While others reveal hidden histories of a city and teach us about important political causes. But the most exciting thing about ARGs is that they have the potential to inspire participants to imagine their everyday tools and places as resources for their own creative endeavors. Deb Polson will be presenting some of the most inspiring ARGs of recent years and revealing some of the design techniques that were used to create them. Most significantly Deb will discuss ways in which educators can imagine using ARGs as rich teaching tools that inspire collaborative learning and motivate students to engage in all kinds of subject matter.
Resumo:
Chlamydia pneumoniae is a common human and animal pathogen associated with a wide range of upper and lower respiratory tract infections. In more recent years there has been increasing evidence to suggest a link between C. pneumoniae and chronic diseases in humans, including atherosclerosis, stroke and Alzheimer’s disease. C. pneumoniae human strains show little genetic variation, indicating that the human-derived strain originated from a common ancestor in the recent past. Despite extensive information on the genetics and morphology processes of the human strain, knowledge concerning many other hosts (including marsupials, amphibians, reptiles and equines) remains virtually unexplored. The koala (Phascolarctos cinereus) is a native Australian marsupial under threat due to habitat loss, predation and disease. Koalas are very susceptible to chlamydial infections, most commonly affecting the conjunctiva, urogenital tract and/or respiratory tract. To address this gap in the literature, the present study (i) provides a detailed description of the morphologic and genomic architecture of the C. pneumoniae koala (and human) strain, and shows that the koala strain is microscopically, developmentally and genetically distinct from the C. pneumoniae human strain, and (ii) examines the genetic relationship of geographically diverse C. pneumoniae isolates from human, marsupial, amphibian, reptilian and equine hosts, and identifies two distinct lineages that have arisen from animal-to-human cross species transmissions. Chapter One of this thesis explores the scientific problem and aims of this study, while Chapter Two provides a detailed literature review of the background in this field of work. Chapter Three, the first results chapter, describes the morphology and developmental stages of C. pneumoniae koala isolate LPCoLN, as revealed by fluorescence and transmission electron microscopy. The profile of this isolate, when cultured in HEp-2 human epithelial cells, was quite different to the human AR39 isolate. Koala LPCoLN inclusions were larger; the elementary bodies did not have the characteristic pear-shaped appearance, and the developmental cycle was completed within a shorter period of time (as confirmed by quantitative real-time PCR). These in vitro findings might reflect biological differences between koala LPCoLN and human AR39 in vivo. Chapter Four describes the complete genome sequence of the koala respiratory pathogen, C. pneumoniae LPCoLN. This is the first animal isolate of C. pneumoniae to be fully-sequenced. The genome sequence provides new insights into genomic ‘plasticity’ (organisation), evolution and biology of koala LPCoLN, relative to four complete C. pneumoniae human genomes (AR39, CWL029, J138 and TW183). Koala LPCoLN contains a plasmid that is not shared with any of the human isolates, there is evidence of gene loss in nucleotide salvage pathways, and there are 10 hot spot genomic regions of variation that were previously not identified in the C. pneumoniae human genomes. Sequence (partial-length) from a second, independent, wild koala isolate (EBB) at several gene loci confirmed that the koala LPCoLN isolate was representative of a koala C. pneumoniae strain. The combined sequence data provides evidence that the C. pneumoniae animal (koala LPCoLN) genome is ancestral to the C. pneumoniae human genomes and that human infections may have originated from zoonotic infections. Chapter Five examines key genome components of the five C. pneumoniae genomes in more detail. This analysis reveals genomic features that are shared by and/or contribute to the broad ecological adaptability and evolution of C. pneumoniae. This analysis resulted in the identification of 65 gene sequences for further analysis of intraspecific variation, and revealed some interesting differences, including fragmentation, truncation and gene decay (loss of redundant ancestral traits). This study provides valuable insights into metabolic diversity, adaptation and evolution of C. pneumoniae. Chapter Six utilises a subset of 23 target genes identified from the previous genomic comparisons and makes a significant contribution to our understanding of genetic variability among C. pneumoniae human (11) and animal (6 amphibian, 5 reptilian, 1 equine and 7 marsupial hosts) isolates. It has been shown that the animal isolates are genetically diverse, unlike the human isolates that are virtually clonal. More convincing evidence that C. pneumoniae originated in animals and recently (in the last few hundred thousand years) crossed host species to infect humans is provided in this study. It is proposed that two animal-to-human cross species events have occurred in the context of the results, one evident by the nearly clonal human genotype circulating in the world today, and the other by a more animal-like genotype apparent in Indigenous Australians. Taken together, these data indicate that the C. pneumoniae koala LPCoLN isolate has morphologic and genomic characteristics that are distinct from the human isolates. These differences may affect the survival and activity of the C. pneumoniae koala pathogen in its natural host, in vivo. This study, by utilising the genetic diversity of C. pneumoniae, identified new genetic markers for distinguishing human and animal isolates. However, not all C. pneumoniae isolates were genetically diverse; in fact, several isolates were highly conserved, if not identical in sequence (i.e. Australian marsupials) emphasising that at some stage in the evolution of this pathogen, there has been an adaptation/s to a particular host, providing some stability in the genome. The outcomes of this study by experimental and bioinformatic approaches have significantly enhanced our knowledge of the biology of this pathogen and will advance opportunities for the investigation of novel vaccine targets, antimicrobial therapy, or blocking of pathogenic pathways.
Resumo:
Regeneration of osseous defects by tissue-engineering approach provides a novel means of treatment utilizing cell biology, materials science, and molecular biology. The concept of in vitro cultured osteoblasts having an ability to induce new bone formation has been demonstrated in the critical size defects using small animal models. The bone derived cells can be incorporated into bioengineered scaffolds and synthesize bone matrix, which on implantation can induce new bone formation. In search of optimal cell delivery materials, the extracellular matrix as cell carriers for the repair and regeneration of tissues is receiving increased attention. We have investigated extracellular matrix formed by osteoblasts in vitro as a scaffold for osteoblasts transplantation and found a mineralized matrix, formed by human osteoblasts in vitro, can initiate bone formation by activating endogenous mesenchymal cells. To repair the large bone defects, osteogenic or stem cells need to be prefabricated in a large three dimensional scaffold usually made of synthetic biomaterials, which have inadequate interaction with cells and lead to in vivo foreign body reactions. The interstitial extracellular matrix has been applied to modify biomaterials surface and identified vitronectin, which binds the heparin domain and RGD (Arg-Gly-Asp) sequence can modulate cell spreading, migration and matrix formation on biomaterials. We also synthesized a tri-block copolymer, methoxy-terminated poly(ethylene glycol)(MPEG)-polyL-lactide(PLLA)-polylysine(PLL) for human osteoblasts delivery. We identified osteogenic activity can be regulated by the molecular weight and composition of the triblock copolymers. Due to the sequential loss of lineage differentiation potential during the culture of bone marrow stromal cells that hinderers their potential clinical application, we have developed a clonal culture system and established several stem cell clones with fast growing and multi-differentiation properties. Using proteomics and subtractive immunization, several differential proteins have been identified and verified their potential application in stem cell characterization and tissue regeneration
Resumo:
The requirement to prove a society united by a body of law and customs to establish native title rights has been identified as a major hurdle to achieving native title recognition. The recent appeal decision of the Federal Court in Sampi on behalf of the Bardi and Jawi People v Western Australia [2010] opens the potential for a new judicial interpretation of society based on the internal view of native title claimants. The decision draws on defining features of legal positivism to inform the court’s findings as to the existence of a single Bardi Jawi society of ‘one people’ living under ‘one law’. The case of Bodney v Bennell [2008] is analysed through comparitive study of how the application of the received positivist framework may limit native title recognition. This paper argues that the framing of Indigenous law by reference to Western legal norms is problematic due to the assumptions of legal positivism and that an internal view based on Indigenous worldviews, which see law as intrinsically linked to the spiritual and ancestral connection to country, is more appropriate to determine proof in native title claims.
Resumo:
The proportion of functional sequence in the human genome is currently a subject of debate. The most widely accepted figure is that approximately 5% is under purifying selection. In Drosophila, estimates are an order of magnitude higher, though this corresponds to a similar quantity of sequence. These estimates depend on the difference between the distribution of genomewide evolutionary rates and that observed in a subset of sequences presumed to be neutrally evolving. Motivated by the widening gap between these estimates and experimental evidence of genome function, especially in mammals, we developed a sensitive technique for evaluating such distributions and found that they are much more complex than previously apparent. We found strong evidence for at least nine well-resolved evolutionary rate classes in an alignment of four Drosophila species and at least seven classes in an alignment of four mammals, including human. We also identified at least three rate classes in human ancestral repeats. By positing that the largest of these ancestral repeat classes is neutrally evolving, we estimate that the proportion of nonneutrally evolving sequence is 30% of human ancestral repeats and 45% of the aligned portion of the genome. However, we also question whether any of the classes represent neutrally evolving sequences and argue that a plausible alternative is that they reflect variable structure-function constraints operating throughout the genomes of complex organisms.
Resumo:
The monogeneric family Fergusoninidae consists of gall-forming flies that, together with Fergusobia (Tylenchida: Neotylenchidae) nematodes, form the only known mutualistic association between insects and nematodes. In this study, the entire 16,000 bp mitochondrial genome of Fergusonina taylori Nelson and Yeates was sequenced. The circular genome contains one encoding region including 27 genes and one non-coding A þT-rich region. The arrangement of the proteincoding, ribosomal RNA (rRNA) and transfer RNA (tRNA) genes was the same as that found in the ancestral insect. Nucleotide composition is highly A þ T biased. All of the protein initiation codons are ATN, except for nad1 which begins with TTT. All 22 tRNA anticodons of F. taylori match those observed in Drosophila yakuba, and all form the typical cloverleaf structure except for tRNA-Ser (AGN) which lacks a dihydrouridine (DHU) arm. Secondary structural features of the rRNA genes of Fergusonina are similar to those proposed for other insects, with minor modifications. The mitochondrial genome of Fergusonina presented here may prove valuable for resolving the sister group to the Fergusoninidae, and expands the available mtDNA data sources for acalyptrates overall.
Resumo:
The semiaquatic platypus and terrestrial echidnas (spiny anteaters) are the only living egg-laying mammals (monotremes). The fossil record has provided few clues as to their origins and the evolution of their ecological specializations; however, recent reassignment of the Early Cretaceous Teinolophos and Steropodon to the platypus lineage implies that platypuses and echidnas diverged >112.5 million years ago, reinforcing the notion of monotremes as living fossils. This placement is based primarily on characters related to a single feature, the enlarged mandibular canal, which supplies blood vessels and dense electrosensory receptors to the platypus bill. Our reevaluation of the morphological data instead groups platypus and echidnas to the exclusion of Teinolophos and Steropodon and suggests that an enlarged mandibular canal is ancestral for monotremes (partly reversed in echidnas, in association with general mandibular reduction). A multigene evaluation of the echidna–platypus divergence using both a relaxed molecular clock and direct fossil calibrations reveals a recent split of 19–48 million years ago. Platypus-like monotremes (Monotrematum) predate this divergence, indicating that echidnas had aquatically foraging ancestors that reinvaded terrestrial ecosystems. This ecological shift and the associated radiation of echidnas represent a recent expansion of niche space despite potential competition from marsupials. Monotremes might have survived the invasion of marsupials into Australasia by exploiting ecological niches in which marsupials are restricted by their reproductive mode. Morphology, ecology, and molecular biology together indicate that Teinolophos and Steropodon are basal monotremes rather than platypus relatives, and that living monotremes are a relatively recent radiation.