218 resultados para Palladio, Andrea, 1508-1580.
Resumo:
In recent years face recognition systems have been applied in various useful applications, such as surveillance, access control, criminal investigations, law enforcement, and others. However face biometric systems can be highly vulnerable to spoofing attacks where an impostor tries to bypass the face recognition system using a photo or video sequence. In this paper a novel liveness detection method, based on the 3D structure of the face, is proposed. Processing the 3D curvature of the acquired data, the proposed approach allows a biometric system to distinguish a real face from a photo, increasing the overall performance of the system and reducing its vulnerability. In order to test the real capability of the methodology a 3D face database has been collected simulating spoofing attacks, therefore using photographs instead of real faces. The experimental results show the effectiveness of the proposed approach.
Resumo:
Instances of parallel ecotypic divergence where adaptation to similar conditions repeatedly cause similar phenotypic changes in closely related organisms are useful for studying the role of ecological selection in speciation. Here we used a combination of traditional and next generation genotyping techniques to test for the parallel divergence of plants from the Senecio lautus complex, a phenotypically variable groundsel that has adapted to disparate environments in the South Pacific. Phylogenetic analysis of a broad selection of Senecio species showed that members of the S. lautus complex form a distinct lineage that has diversified recently in Australasia. An inspection of thousands of polymorphisms in the genome of 27 natural populations from the S. lautus complex in Australia revealed a signal of strong genetic structure independent of habitat and phenotype. Additionally, genetic differentiation between populations was correlated with the geographical distance separating them, and the genetic diversity of populations strongly depended on geographical location. Importantly, coastal forms appeared in several independent phylogenetic clades, a pattern that is consistent with the parallel evolution of these forms. Analyses of the patterns of genomic differentiation between populations further revealed that adjacent populations displayed greater genomic heterogeneity than allopatric populations and are differentiated according to variation in soil composition. These results are consistent with a process of parallel ecotypic divergence in face of gene flow.
Resumo:
Background Glutamate is the principal excitatory neurotransmitter in the central nervous system which acts by the activation of either ionotropic (AMPA, NMDA and kainate receptors) or G-protein coupled metabotropic receptors. Glutamate is widely accepted to play a major role in the path physiology of migraine as implicated by data from animal and human studies. Genes involved in synthesis, metabolism and regulation of both glutamate and its receptors could be, therefore, considered as potential candidates for causing/predisposing to migraine when mutated. Methods The association of polymorphic variants of GRIA1-GRIA4 genes which encode for the four subunits (GluR1-GluR4) of the alpha-amino-3- hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptor for glutamate was tested in migraineurs with and without aura (MA and MO) and healthy controls. Results Two variants in the regulative regions of GRIA1 (rs2195450) and GRIA3 (rs3761555) genes resulted strongly associated with MA (P = 0.00002 and P = 0.0001, respectively), but not associated with MO, suggesting their role in cortical spreading depression. Whereas the rs548294 variant in GRIA1 gene showed association primarily with MO phenotype, supporting the hypothesis that MA and MO phenotypes could be genetically related. These variants modify binding sites for transcription factors altering the expression of GRIA1 and GRIA3 genes in different conditions. Conclusions This study represents the first genetic evidence of a link between glutamate receptors and migraine.
Resumo:
Originating from the World Health Organization of alma Ata in 1978, the philosophy of Comprehensive Primary Health Care (CPHC) includes the interconnecting principles of equity, access, empowerment, community self-determination and intersectoral collaboration in order to achieve better health outcomes for all people. It encompasses addressing the social, economic, cultural and political determinants of health. CPHC when implemented correctly should lead to social inclusion. However, implementing CPHC is complex due to misunderstandings about what it encompasses and about how to achieve the intended goals. This workshop aims to explore a range of issues that are tackled through a diverse range of primary health care services that target: community health, youth mental health, HIV/AIDS, homelessness, and marginalised disadvantaged groups.
Resumo:
This professional doctorate included a major research project investigating the efficacy of acting methodologies taught at four leading Australian actor-training institutions - National Institute of Dramatic Art, Queensland University of Technology, Victorian College of the Arts, and Western Australian Academy of Performing Arts. This study represents the first review of its kind, in which the 'castability' of acting graduates from each of these schools was scrutinized by industry leaders. The study not only reveals the methodologies and philosophies of each school but determines an ideal set of practices for future consideration. The doctorate also included two practice-led projects examining the candidate's transition from actor and teacher of actors to theatre director. The candidate's qualitative study was also underpinned by reflective practice on her extensive professional experience as actor, teacher and director.
Resumo:
A controlled layer of multi-wall carbon nanotubes (MWCNT) was grown directly on top of fluorine-doped tin oxide (FTO) glass electrodes as a surface modifier for improving the performance of polymer solar cells. By using low-temperature chemical vapor deposition with short synthesis times, very short MWCNTs were grown, these uniformly decorating the FTO surface. The chemical vapor deposition parameters were carefully refined to balance the tube size and density, while minimizing the decrease in conductivity and light harvesting of the electrode. As created FTO/CNT electrodes were applied to bulk-heterojunction polymer solar cells, both in direct and inverted architecture. Thanks to the inclusion of MWCNT and the consequent nano-structuring of the electrode surface, we observe an increase in external quantum efficiency in the wavelength range from 550 to 650 nm. Overall, polymer solar cells realized with these FTO/CNT electrodes attain power conversion efficiency higher than 2%, outclassing reference cells based on standard FTO electrodes.
Resumo:
The Life Drama project is a drama-based sexual health promotion project, developed by a cross-cultural research team in Papua New Guinea (PNG) over the past four years. Recognising the limitations of established theatre-in-education and theatre-for-development approaches when working across cultures, the research team explored ways of tapping into the everyday performativity of PNG participants and their communities in order to communicate more powerfully about the personal and social issues involved in sexual health. Through the Folk Opera form, developed by PNG theatre company Raun Raun Theatre around the time of national Independence, the research explored the importance of "story" in identity formation, maintenance and change, the communication of meaning, and the transmission of tacit local knowledges. In a highly diverse and rapidly-changing country like PNG, enacted stories inherently compel the exchange and exploration of different knowledges, and promote the dialogue and ownership that drives social change. The paper will present and unpack the Folk Opera form as developed in the Life Drama program, drawing conclusions which may apply to other programs which to promote health and social justice across cultures.
Resumo:
Atomic scale periodic ripples that extend for several nanometers on the surface of adjacent graphitic grains have been observed for the first time on highly ordered pyrolitic graphite by UHV-STM. The ripples emanate from a grain boundary, and are explained in terms of a mechanical deformation due to the elastic strain accumulated along the GB, which is relieved out-of-plane in the topmost graphene layer. We present a molecular dynamics model that accounts for the formation of similar ripples as result of the lattice mismatch induced by two different grain orientations.
Much ado about nothing? Tracing the progress of innovations borne on enterprise social network sites
Resumo:
Enterprise social networks are organizationally bounded online platforms for users to interact with another and maintain interpersonal relationships. The allure of these technologies is often seen in intra-organizational communication, collaboration and innovation. How these technologies actually support organizational innovation efforts remains unclear. A specific challenge is whether digital content on these platforms converts to actual innovation development efforts. In this study we set out to examine innovation-centric content flows on enterprise social networking platforms, and advance a conceptual model that seeks to explain which innovation conveyed in the digital content will traverse from the digital platform into regular processes. We describe important constructs of our model and offer strategies for the operationalization of the constructs. We conclude with an outlook to our ongoing empirical study that will explore and validate the key propositions of our model, and we sketch some potential implications for industry and academia.
Resumo:
Over the past decade, most Australian universities have moved increasingly towards online course delivery for both undergraduate and graduate programs. In almost all cases, elements of online teaching are part of routine teaching loads. Yet detailed and accurate workload data are not readily available. As a result, institutional policies on academic staff workload are often guided more by untested assumptions about reduction of costs per student unit, rather than being evidence-based, with the result that implementation of new technologies for online teaching has resulted in poorly defined workload expectations. While the academics in this study often revealed a limited understanding of their institutional workload formulas, which in Australia are negotiated between management and the national union through their local branches, the costs of various types of teaching delivery have become a critical issue in a time of increasing student numbers, declining funding, pressures to increase quality and introduce minimum standards of teaching and curriculum, and substantial expenditure on technologies to support e-learning. There have been relatively few studies on the costs associated with workload for online teaching, and even fewer on the more ubiquitous ‘blended’, ‘hybrid’ or ‘flexible’ modes, in which face-to-face teaching is supplemented by online resources and activities. With this in mind the research reported here has attempted to answer the following question: What insights currently inform Australian universities about staff workload when teaching online?
Resumo:
Digital human modeling (DHM) systems underwent significant development within the last years. They achieved constantly growing importance in the field of ergonomic workplace design, product development, product usability, ergonomic research, ergonomic education, audiovisual marketing and the entertainment industry. They help to design ergonomic products as well as healthy and safe socio-technical work systems. In the domain of scientific DHM systems, no industry specific standard interfaces are defined which could facilitate the exchange of 3D solid body data, anthropometric data or motion data. The focus of this article is to provide an overview of requirements for a reliable data exchange between different DHM systems in order to identify suitable file formats. Examples from the literature are discussed in detail. Methods: As a first step a literature review is conducted on existing studies and file formats for exchanging data between different DHM systems. The found file formats can be structured into different categories: static 3D solid body data exchange, anthropometric data exchange, motion data exchange and comprehensive data exchange. Each file format is discussed and advantages as well as disadvantages for the DHM context are pointed out. Case studies are furthermore presented, which show first approaches to exchange data between DHM systems. Lessons learnt are shortly summarized. Results: A selection of suitable file formats for data exchange between DHM systems is determined from the literature review.
Resumo:
The diagnostics of mechanical components operating in transient conditions is still an open issue, in both research and industrial field. Indeed, the signal processing techniques developed to analyse stationary data are not applicable or are affected by a loss of effectiveness when applied to signal acquired in transient conditions. In this paper, a suitable and original signal processing tool (named EEMED), which can be used for mechanical component diagnostics in whatever operating condition and noise level, is developed exploiting some data-adaptive techniques such as Empirical Mode Decomposition (EMD), Minimum Entropy Deconvolution (MED) and the analytical approach of the Hilbert transform. The proposed tool is able to supply diagnostic information on the basis of experimental vibrations measured in transient conditions. The tool has been originally developed in order to detect localized faults on bearings installed in high speed train traction equipments and it is more effective to detect a fault in non-stationary conditions than signal processing tools based on spectral kurtosis or envelope analysis, which represent until now the landmark for bearings diagnostics.
Resumo:
Bone defect treatments can be augmented by mesenchymal stem cell (MSC) based therapies. MSC interaction with the extracellular matrix (ECM) of the surrounding tissue regulates their functional behavior. Understanding of these specific regulatory mechanisms is essential for the therapeutic stimulation of MSC in vivo. However, these interactions are presently only partially understood. This study examined in parallel, for the first time, the effects on the functional behavior of MSCs of 13 ECM components from bone, cartilage and hematoma compared to a control protein, and hence draws conclusions for rational biomaterial design. ECM components specifically modulated MSC adhesion, migration, proliferation, and osteogenic differentiation, for example, fibronectin facilitated migration, adhesion, and proliferation, but not osteogenic differentiation, whereas fibrinogen enhanced adhesion and proliferation, but not migration. Subsequently, the integrin expression pattern of MSCs was determined and related to the cell behavior on specific ECM components. Finally, on this basis, peptide sequences are reported for the potential stimulation of MSC functions. Based on the results of this study, ECM component coatings could be designed to specifically guide cell functions.
Resumo:
We write in response to the letter by Liu et al. [1] commenting on our article, ‘‘Mesenchymal Stem Cells Regulate Angiogenesis According to Their Mechanical Environment’’ [2]. The study by Liu et al. demonstrates that the commonly used endogeneous reference gene (ERG), b-actin, is upregulated by mechanical loading, indicating a potential bias in the determined target gene expression when normalizing to b-actin, such as in our report on unchanged vascular endothelial growth factor (VEGF) and hypoxia-inducible factors (HIF)-1a mRNA levels in mechanically loaded mesenchymal stem cells (MSCs).