Hybrid phoneme based clustering approach for audio driven facial animation

We consider the problem of producing accurate facial animation corresponding to a given input speech signal. A popular technique previously used for Audio Driven Facial Animation is to build a joint audio-visual model using Active Appearance Models (AAMs) to represent possible facial variations and Hidden Markov Models (HMMs) to select the correct appearance based on the input audio. However there are several questions that remained unanswered. In particular the choice of clustering technique and the choice of the number of clusters in the HMM may have significant influence over the quality of the produced videos. We have investigated a range of clustering techniques in order to improve the quality of the HMM produced, and proposed a new structure based on using Gaussian Mixture Models (GMMs) to model each phoneme separately. We compared our approach to several alternatives using a public dataset of 300 phonetically labeled sentences spoken by a single person and found that our approach produces more accurate animation. In addition, we use a hybrid approach where the training data is phonetically labeled thus producing a model with better separation of phonemes, but test audio data is not labeled, thus making our approach for generating facial animation less laborious and fully automatic

Relaxed Molecular Clock Provides Evidence for Long-Distance Dispersal of Nothofagus (Southern Beech)

Nothofagus (southern beech), with an 80-million-year-old fossil record, has become iconic as a plant genus whose ancient Gondwanan relationships reach back into the Cretaceous era. Closely associated with Wegener's theory of “Kontinentaldrift”, Nothofagus has been regarded as the “key genus in plant biogeography”. This paradigm has the New Zealand species as passengers on a Moa's Ark that rafted away from other landmasses following the breakup of Gondwana. An alternative explanation for the current transoceanic distribution of species seems almost inconceivable given that Nothofagus seeds are generally thought to be poorly suited for dispersal across large distances or oceans. Here we test the Moa's Ark hypothesis using relaxed molecular clock methods in the analysis of a 7.2-kb fragment of the chloroplast genome. Our analyses provide the first unequivocal molecular clock evidence that, whilst some Nothofagus transoceanic distributions are consistent with vicariance, trans-Tasman Sea distributions can only be explained by long-distance dispersal. Thus, our analyses support the interpretation of an absence of Lophozonia and Fuscospora pollen types in the New Zealand Cretaceous fossil record as evidence for Tertiary dispersals of Nothofagus to New Zealand. Our findings contradict those from recent cladistic analyses of biogeographic data that have concluded transoceanic Nothofagus distributions can only be explained by vicariance events and subsequent extinction. They indicate that the biogeographic history of Nothofagus is more complex than envisaged under opposing polarised views expressed in the ongoing controversy over the relevance of dispersal and vicariance for explaining plant biodiversity. They provide motivation and justification for developing more complex hypotheses that seek to explain the origins of Southern Hemisphere biota

Activation of an NLRP3 Inflammasome Restricts Mycobacterium kansasii Infection

Mycobacterium kansasii has emerged as an important nontuberculous mycobacterium pathogen, whose incidence and prevalence have been increasing in the last decade. M. kansasii can cause pulmonary tuberculosis clinically and radiographically indistinguishable from that caused by Mycobacterium tuberculosis infection. Unlike the widely-studied M. tuberculosis, little is known about the innate immune response against M. kansasii infection. Although inflammasome activation plays an important role in host defense against bacterial infection, its role against atypical mycobacteria remains poorly understood. In this report, the role of inflammasome activity in THP-1 macrophages against M. kansasii infection was studied. Results indicated that viable, but not heat-killed, M. kansasii induced caspase-1-dependent IL-1β secretion in macrophages. The underlying mechanism was found to be through activation of an inflammasome containing the NLR (Nod-like receptor) family member NLRP3 and the adaptor protein ASC (apoptosis-associated speck-like protein containing a CARD). Further, potassium efflux, lysosomal acidification, ROS production and cathepsin B release played a role in M. kansasii-induced inflammasome activation. Finally, the secreted IL-1β derived from caspase-1 activation was shown to restrict intracellular M. kansasii. These findings demonstrate a biological role for the NLRP3 inflammasome in host defense against M. kansasii

Listeria pathogenesis and molecular virulence determinants

The gram-positive bacterium Listeria monocytogenes is the causative agent of listeriosis, a highly fatal opportunistic foodborne infection. Pregnant women, neonates, the elderly, and debilitated or immunocompromised patients in general are predominantly affected, although the disease can also develop in normal individuals. Clinical manifestations of invasive listeriosis are usually severe and include abortion, sepsis, and meningoencephalitis. Listeriosis can also manifest as a febrile gastroenteritis syndrome. In addition to humans, L. monocytogenes affects many vertebrate species, including birds. Listeria ivanovii, a second pathogenic species of the genus, is specific for ruminants. Our current view of the pathophysiology of listeriosis derives largely from studies with the mouse infection model. Pathogenic listeriae enter the host primarily through the intestine. The liver is thought to be their first target organ after intestinal translocation. In the liver, listeriae actively multiply until the infection is controlled by a cell-mediated immune response. This initial, subclinical step of listeriosis is thought to be common due to the frequent presence of pathogenic L. monocytogenes in food. In normal indivuals, the continual exposure to listerial antigens probably contributes to the maintenance of anti-Listeria memory T cells. However, in debilitated and immunocompromised patients, the unrestricted proliferation of listeriae in the liver may result in prolonged low-level bacteremia, leading to invasion of the preferred secondary target organs (the brain and the gravid uterus) and to overt clinical disease. L. monocytogenes and L. ivanovii are facultative intracellular parasites able to survive in macrophages and to invade a variety of normally nonphagocytic cells, such as epithelial cells, hepatocytes, and endothelial cells. In all these cell types, pathogenic listeriae go through an intracellular life cycle involving early escape from the phagocytic vacuole, rapid intracytoplasmic multiplication, bacterially induced actin-based motility, and direct spread to neighboring cells, in which they reinitiate the cycle. In this way, listeriae disseminate in host tissues sheltered from the humoral arm of the immune system. Over the last 15 years, a number of virulence factors involved in key steps of this intracellular life cycle have been identified. This review describes in detail the molecular determinants of Listeria virulence and their mechanism of action and summarizes the current knowledge on the pathophysiology of listeriosis and the cell biology and host cell responses to Listeria infection. This article provides an updated perspective of the development of our understanding of Listeria pathogenesis from the first molecular genetic analyses of virulence mechanisms reported in 1985 until the start of the genomic era of Listeria research

Aspects of the regulation of inflorescence initiation in white clover (Trifolium repens L.) : a thesis ... for the degree of Master of Science in Botany at Massey University

Thomas (1962), found that after a pretreatment of warm short days, one genotype of 'Grasslands Huia' white clover, clone C, flowered in long days. Another 'Grasslands Huia' genotype did not, (clone B). Experiments with clone C revealed the following: (a) Production of a translocatable floral stimulus occurred in long days and continuous light. (b) Production of either translocatable inhibitory or promotive factors did not occur in short days. Although flowering was caused by long days, flowering eventually stopped. Experiments designed to test the hypothesis that this was caused by the build up of translocatable inhibitors were inconclusive. There was no evidence in the same experiments that translocatable products produced in short days stopped the cessation of flowering. The effect of the short day light intensity on flowering in long days was also examined. Results indicated that in long day conditions when the photoperiod was near the critical daylength, the light intensity of the short day pretreatment limited flowering. At higher daylengths and in higher long day light intensities, the short day light intensity had no influence on flowering. This supports the idea of Thomas (1981), that a balance between two factors, one inhibitory one promotive controls flowering. Further support for this concept came from studies with clone B in which it was found that a cool pretreatment would enable clone B to flower in continuous light but not in 16h photoperiods. Other experiments with clone B, showed that it produced a translocatable floral stimulus in continuous light. There was no evidence that clone B produced translocatable inhibitors in vegetative conditions although there were indication that warm conditions could inhibit the response of the apex to the floral stimulus. Grafts of clone C on clone C, clone B on clone C, Kalinin A on clone C, were used to test the hypothesis that apical factors limited apical responses to the floral stimulus. Given that clone B had the weakest response to the floral stimulus from clone c, and Kalinin A had a stronger response than clone C it would seem that the hypothesis is correct. Grafts were also used to test the hypotheses that (a) Clone B produced translocatable inhibitors which blocked flowering. (b) Clone B produced a translocatable floral stimulus which it was inhibited from responding to. Neither hypothesis was supported by the results. In conclusion it appeared that a balance between two factors controlled the amount of the floral stimulus translocated from the leaves. It also seemed likely that a interaction between the floral stimulus and the apex had a regulatory role. Differences between white clover genotypes are probably due to differences in apical and leaf processes. The limitations of the experimental methods and futive experiments were also discussed

Phylogeny, Radiation, and Transoceanic Dispersal of New Zealand Alpine Buttercups: Molecular Evidence under Split Decomposition

Volume: 88Start Page: 458End Page: 47

A HYBRID PHONEME BASED CLUSTERING APPROACH FOR AUDIO DRIVEN FACIAL ANIMATION

We consider the problem of producing accurate facial animation corresponding to a given input speech signal. A popular technique previously used for Audio Driven Facial Animation is to build a joint audio-visual model using Active Appearance Models (AAMs) to represent possible facial variations and Hidden Markov Models (HMMs) to select the correct appearance based on the input audio. However there are several questions that remained unanswered. In particular the choice of clustering technique and the choice of the number of clusters in the HMM may have significant influence over the quality of the produced videos. We have investigated a range of clustering techniques in order to improve the quality of the HMM produced, and proposed a new structure based on using Gaussian Mixture Models (GMMs) to model each phoneme separately. We compared our approach to several alternatives using a public dataset of 300 phonetically labeled sentences spoken by a single person and found that our approach produces more accurate animation. In addition, we use a hybrid approach where the training data is phonetically labeled thus producing a model with better separation of phonemes, but test audio data is not labeled, thus making our approach for generating facial animation less laborious and fully automatic. 1

Southern Hemisphere Maps and Present-Day <i>Nothofagus</i> Distribution

<div><p>(A) Transoceanic distribution of <i>Nothofagus</i> subspecies <i>Lophozonia</i> and <i>Fuscospora</i> and South American species N. nitida (subgenus <i>Nothofagus</i>). Map adapted from Swenson et al. [<a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0030014#pbio-0030014-b43" target="_blank">43</a>]. ASE, Australia; NCA, New Caledonia; NGU, New Guinea; NZE, New Zealand; SAM, South America; TAS, Tasmania.</p> <p>(B) Relationship of Australia, New Zealand, and South America 65 Myr and 35 Myr before present, reconstructed from <a href="http://www.odsn.de/" target="_blank">http://www.odsn.de/</a> (link “Plate Tectonic Reconstructions”).</p></div