Artykuły w czasopismach na temat „Discriminative Encoder (DisCoder)”

Myxobacteria are an example of how single-cell individuals can transition into multicellular life by an aggregation strategy. For these and all organisms that consist of social groups of cells, discrimination against, and exclusion of, nonself is critical. In myxobacteria, TraA is a polymorphic cell surface receptor that identifies kin by homotypic binding, and in so doing exchanges outer membrane (OM) proteins and lipids between cells with compatible receptors. However, TraA variability alone is not sufficient to discriminate against all cells, as traA allele diversity is not necessarily high among local strains. To increase discrimination ability, myxobacteria include polymorphic OM lipoprotein toxins called SitA in their delivered cargo, which poison recipient cells that lack the cognate, allele-specific SitI immunity protein. We previously characterized 3 SitAI toxin/immunity pairs that belong to 2 families. Here, we discover 4 additional SitA families. Each family is unique in sequence, but share the characteristic features of SitA: OM-associated toxins delivered by TraA. We demonstrate that, within a SitA family, C-terminal nuclease domains are polymorphic and often modular. Remarkably, sitA loci are strikingly numerous and diverse, with most genomes possessing >30 and up to 83 distinct sitAI loci. Interestingly, all SitA protein families are serially transferred between cells, allowing a SitA inhibitor cell to poison multiple targets, including cells that never made direct contact. The expansive suites of sitAI loci thus serve as identify barcodes to exquisitely discriminate against nonself to ensure populations are genetically homogenous to conduct cooperative behaviors.

The key of Weakly Supervised Fine-grained Image Classification (WFGIC) is how to pick out the discriminative regions and learn the discriminative features from them. However, most recent WFGIC methods pick out the discriminative regions independently and utilize their features directly, while neglecting the facts that regions' features are mutually semantic correlated and region groups can be more discriminative. To address these issues, we propose an end-to-end Graph-propagation based Correlation Learning (GCL) model to fully mine and exploit the discriminative potentials of region correlations for WFGIC. Specifically, in discriminative region localization phase, a Criss-cross Graph Propagation (CGP) sub-network is proposed to learn region correlations, which establishes correlation between regions and then enhances each region by weighted aggregating other regions in a criss-cross way. By this means each region's representation encodes the global image-level context and local spatial context simultaneously, thus the network is guided to implicitly discover the more powerful discriminative region groups for WFGIC. In discriminative feature representation phase, the Correlation Feature Strengthening (CFS) sub-network is proposed to explore the internal semantic correlation among discriminative patches' feature vectors, to improve their discriminative power by iteratively enhancing informative elements while suppressing the useless ones. Extensive experiments demonstrate the effectiveness of proposed CGP and CFS sub-networks, and show that the GCL model achieves better performance both in accuracy and efficiency.

Inspired by the many reported successful applications of DNA-encoded chemical libraries in drug discovery projects with protein targets, we decided to apply this platform to nucleic acid targets. We used a 120-billion-compound set of 33 distinct DNA-encoded chemical libraries and affinity-mediated selection to discover binders to a panel of DNA targets. Here, we report the successful discovery of small molecules that specifically interacted with DNA G-quartets, which are stable structural motifs found in G-rich regions of genomic DNA, including in the promoter regions of oncogenes. For this study, we chose the G-quartet sequence found in the c-myc promoter as a primary target. Compounds enriched using affinity-mediated selection against this target demonstrated high-affinity binding and high specificity over DNA sequences not containing G-quartet motifs. These compounds demonstrated a moderate ability to discriminate between different G-quartet motifs and also demonstrated activity in a cell-based assay, suggesting direct target engagement in the cell. DNA-encoded chemical libraries and affinity-mediated selection are uniquely suited to discover binders to targets that have no inherent activity outside of a cellular context, and they may also be of utility in other nucleic acid structural motifs.

An important problem in knowledge discovery from text is the automatic extraction of semantic relations. This paper presents a supervised, semantically intensive, domain independent approach for the automatic detection of part-whole relations in text. First an algorithm is described that identifies lexico-syntactic patterns that encode part-whole relations. A difficulty is that these patterns also encode other semantic relations, and a learning method is necessary to discriminate whether or not a pattern contains a part-whole relation. A large set of training examples have been annotated and fed into a specialized learning system that learns classification rules. The rules are learned through an iterative semantic specialization (ISS) method applied to noun phrase constituents. Classification rules have been generated this way for different patterns such as genitives, noun compounds, and noun phrases containing prepositional phrases to extract part-whole relations from them. The applicability of these rules has been tested on a test corpus obtaining an overall average precision of 80.95% and recall of 75.91%. The results demonstrate the importance of word sense disambiguation for this task. They also demonstrate that different lexico-syntactic patterns encode different semantic information and should be treated separately in the sense that different clarification rules apply to different patterns.

We present a data-driven approach using word embeddings to discover and categorise language biases on the discussion platform Reddit. As spaces for isolated user communities, platforms such as Reddit are increasingly connected to issues of racism, sexism and other forms of discrimination, signalling the need to monitor the language of these groups. One of the most promising AI approaches to trace linguistic biases in large textual datasets involves word embeddings, which transform text into high-dimensional dense vectors and capture semantic relations between words. Yet, previous studies require predefined sets of potential biases to study, e.g., whether gender is more or less associated with particular types of jobs. This makes these approaches unfit to deal with smaller and community-centric datasets such as those on Reddit, which contain smaller vocabularies and slang, as well as biases that may be particular to that community. This paper proposes a data-driven approach to automatically discover language biases encoded in the vocabulary of online discourse communities on Reddit. In our approach, protected attributes are connected to evaluative words found in the data, which are then categorised through a semantic analysis system. We verify the effectiveness of our method by comparing the biases we discover in the Google News dataset with those found in previous literature. We then successfully discover gender bias, religion bias, and ethnic bias in different Reddit communities. We conclude by discussing potential application scenarios and limitations of this data-driven bias discovery method.

The discovery of words in continuous speech is one of the first challenges faced by infants during language acquisition. This process is partially facilitated by statistical learning, the ability to discover and encode relevant patterns in the environment. Here, we used an electroencephalogram (EEG) index of neural entrainment to track 6-month-olds’ ( N = 25) segmentation of words from continuous speech. Infants’ neural entrainment to embedded words increased logarithmically over the learning period, consistent with a perceptual shift from isolated syllables to wordlike units. Moreover, infants’ neural entrainment during learning predicted postlearning behavioral measures of word discrimination ( n = 18). Finally, the logarithmic increase in entrainment to words was comparable in infants and adults, suggesting that infants and adults follow similar learning trajectories when tracking probability information among speech sounds. Statistical-learning effects in infants and adults may reflect overlapping neural mechanisms, which emerge early in life and are maintained throughout the life span.

Abstract Abstract 685 Allogeneic stem cell transplantation (allo-SCT) followed by donor lymphocyte infusion (DLI) is used as a curative treatment for patients with malignant diseases. Donor derived T cells mediate graft versus tumor responses by targeting minor histocompatibility antigens (mHags) that are encoded by patient specific single nucleotide polymorphisms (SNPs). Various approaches have been applied for mHag discovery resulting in the characterization of more than 20 mHags. However, restriction to specific HLA types and unfavourable gene expression strongly limits the number of clinically relevant mHags. Recently, it has been demonstrated that whole genome association scanning (WGAs) can be a tool for mHag identification. Here, we present WGAs as a powerful method for high throughput identification of new mHags. From 2 patients that entered complete remission with limited graft versus host disease after allo-SCT and DLI, activated T cells were cloned by flowcytometric cell sorting. After expansion, 232 stably growing T cell clones were obtained. Patient specific recognition in the absence of donor recognition was demonstrated for 78 clones. By using blocking antibodies and a test panel consisting of partially HLA matched EBV-transformed B cell lines (EBV-LCL), we demonstrated that these 78 T cell clones comprised 20 unique mHag reactivities which could be identified to be restricted to HLA-A*02 or B*07. Since WGAs is based on a balanced segregation of test cells in a positive and a negative group, 15 T cell clones were selected recognizing mHags with population frequencies between 20% to 80% for further analysis. To perform WGAs, a test panel was generated containing 80 HLA-A*02 and B*07 positive EBV-LCL for testing of recognition by all selected T cell clones using Interferon-γ Elisa. In parallel, all EBV-LCL were genotyped for 1 million SNPs using bead arrays. All SNP genotype patterns were combined with each individual T cell recognition pattern. The level of matching between both patterns was statistically analyzed using Fisher's exact test, resulting in p-values indicating the significance of association. Significant association (p-value<10-12) between SNP genotypes and a T cell recognition pattern identified a single genomic region for 12 out of 15 T cell clones. In 2 cases no clear discrimination between positive and negative EBV-LCL could be made, suggesting that these T cell clones may not recognize mHags. Incomplete coverage of a genomic region by SNPs on the bead array may explain the lack of association for 1 T cell clone. For 7 T cell clones, significant association was found with array SNPs located in exons of the genes WNK1, SSR1, PRCP, ARHGDIB, PDCD11, EBI3 and APOBEC3B. For 3 other T cell clones, the genes ERAP1, BCAT2 and GEMIN4 were identified based on significant association with SNPs located in non coding regions. Sequence analysis of the coding regions of these genes from patient and donor revealed additional patient specific SNPs that were not included in the bead array. For the remaining associating TTK and ERGIC1 genes, the coding regions were identical between patient and donor, showing that these mHags are not encoded by exon SNPs in the identified TTK and ERGIC1 genes. Differential mHag expression may be induced in these cases by SNPs in adjacent genes that were not identified by SNPs on the bead array or may be the result of SNPs in non coding regulatory regions or in mRNA splice variants. According to the BioGPS gene expression database, a number of genes as identified by WGAs were predominantly expressed in hematopoietic cells, and may therefore encode relevant targets for T cell therapy. Next, we investigated the amino acid polymorphisms encoded by all identified coding SNPs. Peptides spanning the patient type amino acid polymorphism were submitted to HLA binding prediction algorithms. Candidate peptides were synthesized and T cell recognition was demonstrated at concentrations varying from 0.5 to 5000 nM. Recognition of donor type peptides was absent in all cases, validating the identification of 10 novel mHags. In conclusion, these data demonstrate that activation marker based T cell selection and cloning combined with WGAs results in high throughput discovery of multiple mHags. This strategy therefore allows broad characterization of mHags in donor derived T cell responses and selection of clinically relevant mHags for development of T cell based immunotherapy. Disclosures: No relevant conflicts of interest to declare.

Person re-identification (ReID) plays an important role in intelligent surveillance and receives widespread attention from academics and the industry. Due to extreme changes in viewing angles, some discriminative local regions are suppressed. In addition, the data with similar backgrounds collected by a fixed viewing angle camera will also affect the model’s ability to distinguish a person. Therefore, we need to discover more fine-grained information to form the overall characteristics of each identity. The proposed self-erasing network structure composed of three branches benefits the extraction of global information, the suppression of background noise and the mining of local information. The two self-erasing strategies that we proposed encourage the network to focus on foreground information and strengthen the model’s ability to encode weak features so as to form more effective and richer visual cues of a person. Extensive experiments show that the proposed method is competitive with the advanced methods and achieves state-of-the-art performance on DukeMTMC-ReID and CUHK-03(D) datasets. Furthermore, it can be seen from the activation map that the proposed method is beneficial to spread the attention to the whole body. Both metrics and the activation map validate the effectiveness of our proposed method.

483 Background: Cystoscopy, an invasive, painful and expensive method, is currently the main clinical tool for new diagnosis and disease recurrence detection of bladder cancer (BCa). The need for new biomarkers discovery that is costless, sensitive and specific is urgent. This project aims to study and compare alternative splicing events (ASE) in BCa tissues and normal bladder tissues and ultimately, identify specific spliced events coding for proteins detectable in urine by liquid chromatography–mass spectrometry. Methods: In this study, alterations to the global RNA splicing landscape of cellular genes were investigated in a large-scale screen from 408 BCa tissues and 19 normal tissues provided by The Cancer Genome Atlas (TCGA). Three statistical thresholds were used to determine substantial modifications. All events showing a p-value<0.05 and a level of expression ≥ 50 transcripts per million; -10 ≥ Δ percent splice index ≤10; and a q-value<0.05 were conserved. Next, mRNA expression levels between cancer and normal tissues were compared for all splicing factors and the spliceosome to determine the impact of gene dysregulation on alternative splicing events. Using multiple bioinformatic platforms such as EASANA, MultAlin, ExPasy, NLS Mapper and Pfam, splicing events responsible for significant protein structural changes between cancer and healthy tissue were selected. From this sample chosen, ASEs coding for proteins that could be detected in urine were conserved. Results: Our study identifies modifications in the alternative splicing patterns of 107 transcripts encoded by 97 genes. STRING analysis revealed that many of the gene products interact either directly or indirectly with each other (enrichment p-value = 1x10-10). 61 ASEs are causing important protein changes from which 27 can be detected in urine. Finally, 16 ASEs coding for easily recognizable peptide sequences in urine represented significant targets for potential BCa biomarkers. Conclusions: The TCGA data show the relevance to investigate alternative splicing events in bladder cancer. 16 significant events were detectable in urine and may potentially discriminate between presence or absence of bladder cancer.

Much of the research on gender representations in language teaching materials has focused on providing frequency-based accounts of character appearances, familial/occupational role attributions and sexist language use. However, gender discrimination, when communicated visually, might more readily drop off the already overburdened teacher’s radar. Therefore, this study concentrated not just on the depiction of coursebook images but also on their relation to the learners, and aimed to discover the latent sexism in three thematically similar units from one global and two locally-produced coursebooks widely used in the Turkish and Iranian EFL contexts. A critical analysis of 41 images with Van Leeuwen’s (2008) framework revealed that male overrepresentation prevailed throughout all three resources, though to a lesser extent in the global coursebook. The characters mainly avoided direct contact with the viewers by averting their gaze and offered themselves as visual cues for denotative meanings. The global and Turkish-made series tended to position them both closer to the young readers and at their eye level to help build intimacy with more relatable role models. In their Iranian counterpart, the male and female characters were yet socially distanced from them through long shots taken from low and high angles respectively, in which case men were portrayed as authority figures to be looked up to, and women as the diminished other to be looked down on by the students. While both genders were oftener seen frontally in the Turkish EFL material with mixed-gender authorship, the all-male author teams preferred to show the male characters from an oblique angle to further detachment in the global and Iranian contexts. In establishing relatively closer, more personal and engaging interactions with both boys and girls visually, the global and Turkish EFL materials can be claimed to encode a more inclusive and equitable worldview than their Iranian counterpart.

Abstract Socioeconomic factors and discrimination play major roles in variable cancer treatment outcomes across individuals from different ancestral backgrounds. Tumors from patients of different ancestry groups also have divergent patterns of somatic and germline alterations. This led us to hypothesize that these molecular differences may also contribute to the variable treatment outcomes observed in the clinic. We hypothesized that the ancestry of cell lines would impact their genetic dependencies. To test this hypothesis, we leveraged The Cancer Dependency Map (DepMap) which has performed genome-wide CRISPR screens across &gt;1,000 cell lines and &gt;30 cancer types. We first leveraged variant calls from WES/WGS to infer cell line ancestry, then correlated these ancestries with DepMap gene dependency scores. This analysis was underpowered to detect differences in cell lines of African, American, and South Asian descent, since cell lines from these ancestry groups are poorly represented in DepMap, and in cancer research models in general. We were, however, able to detect 71 gene dependencies that were associated with either European or East Asian ancestry. Since different ancestry groups have divergent patterns of germline alterations, we reasoned that specific germline alterations may result in ancestry-associated dependencies. Surprisingly, we identified cis-QTLs for &gt;75% of the ancestry-associated genes. We originally hypothesized that these variants would alter the function of the encoded protein, but instead found that these variants mapped to the targeting sequences of the sgRNA. This suggests that ancestry-associated mismatches within sgRNA targeting sequences can preclude Cas9-mediated genome editing. To understand this problem systematically, we mapped the germline variants that were catalogued in gnomAD to multiple genome-wide CRISPR libraries. The fraction of affected genes differed from library to library and was typically between 2-5%, but we found that individuals of African descent were consistently more affected by this problem across all CRISPR libraries. This is important because it suggests that cell lines of African descent have a higher rate of false negatives in all CRISPR-based experiments. In total, we identified a subset of genes that have ancestry-associated dependency profiles. Most of these genes are the result of ancestry-associated mismatches within the sgRNA targeting sequences. However, many of these genes are not, and require further investigation to understand the influence of ancestry on these genetic dependencies. Citation Format: Sean Alexander Misek, Aaron Fultineer, Jeremie Kalfon, Javad Noorbakhsh, Isabella Boyle, Joshua Dempster, Lia Petronio, Katherine Huang, James McFarland, Rameen Beroukhim, Jesse Boehm. Ancestry bias in CRISPR guide design impedes discovery of genetic dependencies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2173.

Central among the tools and approaches used for ligand discovery and design are Molecular Dynamics (MD) simulations, which follow the dynamic changes in molecular structure in response to the environmental condition, interactions with other proteins, and the effects of ligand binding. The need for, and successes of, MD simulations in providing this type of essential information are well documented, but so are the challenges presented by the size of the resulting datasets encoding the desired information. The difficulty of extracting information on mechanistically important state-to-state transitions in response to ligand binding and other interactions is compounded by these being rare events in the MD trajectories of complex molecular machines, such as G-protein-coupled receptors (GPCRs). To address this problem, we have developed a protocol for the efficient detection of such events. We show that the novel Rare Event Detection (RED) protocol reveals functionally relevant and pharmacologically discriminating responses to the binding of different ligands to the 5-HT2AR orthosteric site in terms of clearly defined, structurally coherent, and temporally ordered conformational transitions. This information from the RED protocol offers new insights into specific ligand-determined functional mechanisms encoded in the MD trajectories, which opens a new and rigorously reproducible path to understanding drug activity with application in drug discovery.

Current progresses on fine-grained recognition are mainly focus on learning the discriminative feature representation via introducing the visual supervisions e.g. part labels. However, it is time-consuming and needs the professional knowledge to obtain the accuracy annotations. Different from these existing methods based on the visual supervisions, in this paper, we introduce a novel feature named audio visual attributes via discovering the correlations between the visual and audio representations. Specifically, our unified framework is training with video-level category label, which consists of two important modules, the encoder module and the attribute discovery module, to encode the image and audio into vectors and learn the correlations between audio and images, respectively. On the encoder module, we present two types of feed forward convolutional neural network for the image and audio modalities. While an attention driven framework based on recurrent neural network is developed to generate the audio visual attribute representation. Thus, our proposed architecture can be implemented end-to-end in the step of inference. We exploit our models for the problem of fine-grained bird recognition on the CUB200-211 benchmark. The experimental results demonstrate that with the help of audio visual attribute, we achieve the superior or comparable performance to that of strongly supervised approaches on the bird recognition.

In supervised approaches for keyphrase extraction, a candidate phrase is encoded with a set of hand-crafted features and machine learning algorithms are trained to discriminate keyphrases from non-keyphrases. Although the manually-designed features have shown to work well in practice, feature engineering is a difficult process that requires expert knowledge and normally does not generalize well. In this paper, we present SurfKE, a feature learning framework that exploits the text itself to automatically discover patterns that keyphrases exhibit. Our model represents the document as a graph and automatically learns feature representation of phrases. The proposed model obtains remarkable improvements in performance over strong baselines.

AbstractThe problem of fair machine learning has drawn much attention over the last few years and the bulk of offered solutions are, in principle, empirical. However, algorithmic fairness also raises important conceptual issues that would fail to be addressed if one relies entirely on empirical considerations. Herein, I will argue that the current debate has developed an empirical framework that has brought important contributions to the development of algorithmic decision-making, such as new techniques to discover and prevent discrimination, additional assessment criteria, and analyses of the interaction between fairness and predictive accuracy. However, the same framework has also suggested higher-order issues regarding the translation of fairness into metrics and quantifiable trade-offs. Although the (empirical) tools which have been developed so far are essential to address discrimination encoded in data and algorithms, their integration into society elicits key (conceptual) questions such as: What kind of assumptions and decisions underlies the empirical framework? How do the results of the empirical approach penetrate public debate? What kind of reflection and deliberation should stakeholders have over available fairness metrics? I will outline the empirical approach to fair machine learning, i.e. how the problem is framed and addressed, and suggest that there are important non-empirical issues that should be tackled. While this work will focus on the problem of algorithmic fairness, the lesson can extend to other conceptual problems in the analysis of algorithmic decision-making such as privacy and explainability.

AbstractThe brainstem auditory pathway is obligatory for all aural information. Brainstem auditory neurons must encode the level and timing of sounds, as well as their time-dependent spectral properties, the fine structure and envelope, which are essential for sound discrimination. This study focused on envelope coding in the two cochlear nuclei of the barn owl, nucleus angularis (NA) and nucleus magnocellularis (NM). NA and NM receive input from bifurcating auditory nerve fibers and initiate processing pathways specialized in encoding interaural time (ITD) and level (ILD) differences, respectively. We found that NA neurons, though unable to accurately encode stimulus phase, lock more strongly to the stimulus envelope than NM units. The spectrotemporal receptive fields (STRFs) of NA neurons exhibit a pre-excitatory suppressive field. Using multilinear regression analysis and computational modeling, we show that this feature of STRFs can account for enhanced across-trial response reliability, by locking spikes to the stimulus envelope. Our findings indicate a dichotomy in envelope coding between the time and intensity processing pathways as early as at the level of the cochlear nuclei. This allows the ILD processing pathway to encode envelope information with greater fidelity than the ITD processing pathway. Furthermore, we demonstrate that the properties of the neurons’ STRFs can be quantitatively related to spike timing reliability.

AbstractThe brainstem auditory pathway is obligatory for all aural information. Brainstem auditory neurons must encode the level and timing of sounds, as well as their time-dependent spectral properties, the fine structure and envelope, which are essential for sound discrimination. This study focused on envelope coding in the two cochlear nuclei of the barn owl, nucleus angularis (NA) and nucleus magnocellularis (NM). NA and NM receive input from bifurcating auditory nerve fibers and initiate processing pathways specialized in encoding interaural time (ITD) and level (ILD) differences, respectively. We found that NA neurons, though unable to accurately encode stimulus phase, lock more strongly to the stimulus envelope than NM units. The spectrotemporal receptive fields (STRFs) of NA neurons exhibit a pre-excitatory suppressive field. Using multilinear regression analysis and computational modeling, we show that this feature of STRFs can account for enhanced across-trial response reliability, by locking spikes to the stimulus envelope. Our findings indicate a dichotomy in envelope coding between the time and intensity processing pathways as early as at the level of the cochlear nuclei. This allows the ILD processing pathway to encode envelope information with greater fidelity than the ITD processing pathway. Furthermore, we demonstrate that the properties of the neurons’ STRFs can be quantitatively related to spike timing reliability.

Straipsnyje nagrinėjami T. Valentine’o veidų erdvės ir M. B. Lewiso bei R. A. Johnstono Voronoi modeliai, kuriuose pagrindinis dėmesys skiriamas veidų reprezentacijos atmintyje ypatumams. Pažymima, jog veidai reprezentuojami hipotetinėje daugiamatėje veidų erdvėje. Veidų erdvės matmenys (arba geometrinės ašys) atspindi koduojamos veido informacijos požymių įverčius. Tuomet pats veidas apibūdinamas kaip unikalus įvairių matmenų įverčių derinys, kuris gali būti reprezentuotas veidų erdvėje kaip vienintelis abstraktus taškas arba vektorius (pagal tai, ar kodavimo metu atsižvelgiama į veidą-prototipą). Remiantis veidų išsidėstymo erdvėje principais (nuotoliu nuo veido-prototipo ir atstumu tarp reprezentuojamų veidų) aiškinami kai kurie veidų informacijos apdorojimo dėsningumai (pvz., informacijos atgaminimo tikslumas, veidų tarpusavio panašumo, savitumo / tipiškumo nustatymas ir pan.). Pagrindinė problema – netikslus ir nedetalus modeliuose vartojamų sąvokų bei aprašomų veido informacijos apdorojimo procesų apibūdinimas. Tai lemia atliekamų tyrimų rezultatų prieštaringumą ir pasunkina empirinį modelių prielaidų patvirtinimą. MODELS OF FACES REPRESENTATIONKristina Vanagaitė SummaryConsidering that information alteration of faces and other visual stimulus differ qualitative, it is important to establish models, which would enable to explain peculiar consistent patterns of information processing of faces.One of the most important stages of informatikon processing – representation in memory. Recently, seeking to discover the peculiarities of faces representation in memory, the biggest attention is given to face space of T. Valentine and patterns of M. B. Lewis and R. A. Johnston Voronoi.In T. Valentine’s multidimensional face-space framework, faces are encoded according to a series of visual or physical parameter particular to each face. Each of these parameters is represented along a space dimension. The dimensions of the space will be those that serve to discriminate between faces and they represent the perceptual dimensions or features of faces that distinguish the faces. A face’s representation will be made up of many values taken along many different dimensions. This set of values will be unique for every individual face and will be represented as a single point (or vector) in an N-dimensional face-space. The main problem – because of non-comprehensive description of face’s dimension and encoded information of faces it is not clear the way of distinguishing physical and psychological faces’ dimensions, the possibilities to range the encoded face dimensions according to their importance and significance.Two different models based on this framework, norm-based and exemplar-based models are described and contrasted. Models that incorporate the facial prototype are referred to as norm-based models. On such models, faces are represented by face vectors taken relative to the facial prototype at the center of the face-space, which represent the average value of the population on each dimension. Although the existence of face-prototype is certified by the research of faces’ caricature, it is unclear why the faces of representatives of other races are reproduced inaccurate, how are the valuation mediums of encoded faces’ dimension calculated, does the face-prototype is kept in memory as the real face?As an alternative to these – exemplar-based models have face representations that are stored as absolutes, relative only to other exemplars. The present study describes Voronoi diagram, developed from the exemplar-based model, which accounts for the caricature advantage without reference to an explicitly encoded facial prototype. Voronoi diagram involves interpreting the face-space as a space of regions of identity (also called „Voronoi cells“) rather than a set of points or vectors. The advantage of this pattern – the identity of observed face is connected with appropriate „cell“. It is important, because such structure, differently to the pattern oriented to standard, enables to explain the fact, that faces are recognized despite their dimensions or change of circumstances of observation.Distinguishing between these two models remains difficult because they make similar predictions. For example, both models predict that faces that are judged to be distinctive will be recognized faster and more accurately than those judged to be typical. Also indicate that typical faces are generally located near the center of the space in more densely populated facespace while distinctive faces will tend to be present in the outer regions. However, with help of patterns oriented to standards, as well as to examples, it is possible to explain only some of peculiarities of informatikon alteration of faces and the results of empirical researches are quite contradictory. Further analysis of pattern of faces’ expansion is necessary – it would not only specify the hypothetical structure of faces’ expansion, but also elaborate the proceeding processes.

In 1988, historian Nadia Wheatley and indigenous artist Donna Rawlins published their award-winning picture book, My Place, a reinterpretation of Australian national identity and sovereignty prompted by the bicentennial of white settlement. Twenty years later, the Australian Broadcasting Corporation (ABC) commissioned Penny Chapman’s multi-platform project based on this book. The 13 episodes of the television series begin in 2008, each telling the story of a child at a different point in history, and are accompanied by substantial interactive online content. Issues as diverse as religious difference and immigration, wartime conscription and trauma, and the experiences of Aboriginal Australians are canvassed. The program itself, which has a second series currently in production, introduces child audiences to—and implicates them in—a rich ideological fabric of deeply politicised issues that directly engage with vexed questions of Australian nationhood. The series offers a subversive view of Australian history and society, and it is the child—whether protagonist on the screen or the viewer/user of the content—who is left to discover, negotiate and move beyond often problematic societal norms. As one of the public broadcaster’s keystone projects, My Place signifies important developments in ABC’s construction of multicultural child citizenship. The digitisation of Australian television has facilitated a wave of multi-channel and new media innovation. Though the development of a multi-channel ecology has occurred significantly later in Australia than in the US or Europe, in part due to genre restrictions on broadcasters, all major Australian networks now have at least one additional free-to-air channel, make some of their content available online, and utilise various forms of social media to engage their audiences. The ABC has been in the vanguard of new media innovation, leveraging the industry dominance of ABC Online and its cross-platform radio networks for the repurposing of news, together with the additional funding for digital renewal, new Australian content, and a digital children’s channel in the 2006 and 2009 federal budgets. In line with “market failure” models of broadcasting (Born, Debrett), the ABC was once the most important producer-broadcaster for child viewers. With the recent allocation for the establishment of ABC3, it is now the catalyst for a significant revitalisation of the Australian children’s television industry. The ABC Charter requires it to broadcast programs that “contribute to a sense of national identity” and that “reflect the cultural diversity of the Australian community” (ABC Documents). Through its digital children’s channel (ABC3) and its multi-platform content, child viewers are not only exposed to a much more diverse range of local content, but also politicised by an intricate network of online texts connected to the TV programs. The representation of diasporic communities through and within multi-platformed spaces forms a crucial part of the way(s) in which collective identities are now being negotiated in children’s texts. An analysis of one of the ABC’s My Place “projects” and its associated multi-platformed content reveals an intricate relationship between postcolonial concerns and the construction of child citizenship. Multicultural Places, Multi-Platformed Spaces: New Media Innovation at the ABC The 2007 restructure at the ABC has transformed commissioning practices along the lines noted by James Bennett and Niki Strange of the BBC—a shift of focus from “programs” to multi-platform “projects,” with the latter consisting of a complex network of textual production. These “second shift media practices” (Caldwell) involve the tactical management of “user flows structured into and across the textual terrain that serve to promote a multifaceted and prolonged experience of the project” (Bennett and Strange 115). ABC Managing Director Mark Scott’s polemic deployment of the “digital commons” trope (Murdock, From) differs from that of his opposite number at the BBC, Mark Thompson, in its emphasis on the glocalised openness of the Australian “town square”—at once distinct from, and an integral part of, larger conversations. As announced at the beginning of the ABC’s 2009 annual report, the ABC is redefining the town square as a world of greater opportunities: a world where Australians can engage with one another and explore the ideas and events that are shaping our communities, our nation and beyond … where people can come to speak and be heard, to listen and learn from each other. (ABC ii)The broad emphasis on engagement characterises ABC3’s positioning of children in multi-platformed projects. As the Executive Producer of the ABC’s Children’s Television Multi-platform division comments, “participation is very much the mantra of the new channel” (Glen). The concept of “participation” is integral to what has been described elsewhere as “rehearsals in citizenship” (Northam). Writing of contemporary youth, David Buckingham notes that “‘political thinking’ is not merely an intellectual or developmental achievement, but an interpersonal process which is part of the construction of a collective, social identity” (179). Recent domestically produced children’s programs and their associated multimedia applications have significant potential to contribute to this interpersonal, “participatory” process. Through multi-platform experiences, children are (apparently) invited to construct narratives of their own. Dan Harries coined the term “viewser” to highlight the tension between watching and interacting, and the increased sense of agency on the part of audiences (171–82). Various online texts hosted by the ABC offer engagement with extra content relating to programs, with themed websites serving as “branches” of the overarching ABC3 metasite. The main site—strongly branded as the place for its targeted demographic—combines conventional television guide/program details with “Watch Now!,” a customised iView application within ABC3’s own themed interface; youth-oriented news; online gaming; and avenues for viewsers to create digital art and video, or interact with the community of “Club3” and associated message boards. The profiles created by members of Club3 are moderated and proscribe any personal information, resulting in an (understandably) restricted form of “networked publics” (boyd 124–5). Viewser profiles comprise only a username (which, the website stresses, should not be one’s real name) and an “avatar” (a customisable animated face). As in other social media sites, comments posted are accompanied by the viewser’s “name” and “face,” reinforcing the notion of individuality within the common group. The tool allows users to choose from various skin colours, emphasising the multicultural nature of the ABC3 community. Other customisable elements, including the ability to choose between dozens of pre-designed ABC3 assets and feeds, stress the audience’s “ownership” of the site. The Help instructions for the Club3 site stress the notion of “participation” directly: “Here at ABC3, we don’t want to tell you what your site should look like! We think that you should be able to choose for yourself.” Multi-platformed texts also provide viewsers with opportunities to interact with many of the characters (human actors and animated) from the television texts and share further aspects of their lives and fictional worlds. One example, linked to the representation of diasporic communities, is the Abatti Pizza Game, in which the player must “save the day” by battling obstacles to fulfil a pizza order. The game’s prefacing directions makes clear the ethnicity of the Abatti family, who are also visually distinctive. The dialogue also registers cultural markers: “Poor Nona, whatsa she gonna do? Now it’s up to you to help Johnny and his friends make four pizzas.” The game was acquired from the Canadian-animated franchise, Angela Anaconda; nonetheless, the Abatti family, the pizza store they operate and the dilemma they face translates easily to the Australian context. Dramatisations of diasporic contributions to national youth identities in postcolonial or settler societies—the UK (My Life as a Popat, CITV) and Canada (How to Be Indie)—also contribute to the diversity of ABC3’s television offerings and the positioning of its multi-platform community. The negotiation of diasporic and postcolonial politics is even clearer in the public broadcaster’s commitment to My Place. The project’s multifaceted construction of “places,” the ethical positioning of the child both as an individual and a member of (multicultural) communities, and the significant acknowledgement of ongoing conflict and discrimination, articulate a cultural commons that is more open-ended and challenging than the Eurocentric metaphor, the “town square,” suggests. Diversity, Discrimination and Diasporas: Positioning the Viewser of My Place Throughout the first series of My Place, the experiences of children within different diasporic communities are the focal point of five of the initial six episodes, the plots of which revolve around children with Lebanese, Vietnamese, Greek, and Irish backgrounds. This article focuses on an early episode of the series, “1988,” which explicitly confronts the cultural frictions between dominant Anglocentric Australian and diasporic communities. “1988” centres on the reaction of young Lily to the arrival of her cousin, Phuong, from Vietnam. Lily is a member of a diasporic community, but one who strongly identifies as “an Australian,” allowing a nuanced exploration of the ideological conflicts surrounding the issue of so-called “boat people.” The protagonist’s voice-over narration at the beginning of the episode foregrounds her desire to win Australia’s first Olympic gold medal in gymnastics, thus mobilising nationally identified hierarchies of value. Tensions between diasporic and settler cultures are frequently depicted. One potentially reactionary sequence portrays the recurring character of Michaelis complaining about having to use chopsticks in the Vietnamese restaurant; however, this comment is contextualised several episodes later, when a much younger Michaelis, as protagonist of the episode “1958,” is himself discriminated against, due to his Greek background. The political irony of “1988” pivots on Lily’s assumption that her cousin “won’t know Australian.” There is a patronising tone in her warning to Phuong not to speak Vietnamese for fear of schoolyard bullying: “The kids at school give you heaps if you talk funny. But it’s okay, I can talk for you!” This encourages child viewers to distance themselves from this fictional parallel to the frequent absence of representation of asylum seekers in contemporary debates. Lily’s assumptions and attitudes are treated with a degree of scepticism, particularly when she assures her friends that the silent Phuong will “get normal soon,” before objectifying her cousin for classroom “show and tell.” A close-up camera shot settles on Phuong’s unease while the children around her gossip about her status as a “boat person,” further encouraging the audience to empathise with the bullied character. However, Phuong turns the tables on those around her when she reveals she can competently speak English, is able to perform gymnastics and other feats beyond Lily’s ability, and even invents a story of being attacked by “pirates” in order to silence her gossiping peers. By the end of the narrative, Lily has redeemed herself and shares a close friendship with Phuong. My Place’s structured child “participation” plays a key role in developing the postcolonial perspective required by this episode and the project more broadly. Indeed, despite the record project budget, a second series was commissioned, at least partly on the basis of the overwhelmingly positive reception of viewsers on the ABC website forums (Buckland). The intricate My Place website, accessible through the ABC3 metasite, generates transmedia intertextuality interlocking with, and extending the diegesis of, the televised texts. A hyperlinked timeline leads to collections of personal artefacts “owned” by each protagonist, such as journals, toys, and clothing. Clicking on a gold medal marked “History” in Lily’s collection activates scrolling text describing the political acceptance of the phrase “multiculturalism” and the “Family Reunion” policy, which assisted the arrival of 100,000 Vietnamese immigrants. The viewser is reminded that some people were “not very welcoming” of diasporic groups via an explicit reference to Mrs Benson’s discriminatory attitudes in the series. Viewsers can “visit” virtual representations of the program’s sets. In the bedroom, kitchen, living room and/or backyard of each protagonist can be discovered familiar and additional details of the characters’ lives. The artefacts that can be “played” with in the multimedia applications often imply the enthusiastic (and apparently desirable) adoption of “Australianness” by immigrant children. Lily’s toys (her doll, hair accessories, roller skates, and glass marbles) invoke various aspects of western children’s culture, while her “journal entry” about Phuong states that she is “new to Australia but with her sense of humour she has fitted in really well.” At the same time, the interactive elements within Lily’s kitchen, including a bowl of rice and other Asian food ingredients, emphasise cultural continuity. The description of incense in another room of Lily’s house as a “common link” that is “used in many different cultures and religions for similar purposes” clearly normalises a glocalised world-view. Artefacts inside the restaurant operated by Lily’s mother link to information ranging from the ingredients and (flexible) instructions for how to make rice paper rolls (“Lily and Phuong used these fillings but you can use whatever you like!”) to a brief interactive puzzle game requiring the arrangement of several peppers in order from least hot to most hot. A selectable picture frame downloads a text box labelled “Images of Home.” Combined with a slideshow of static, hand-drawn images of traditional Vietnamese life, the text can be read as symbolic of the multiplicity of My Place’s target audience(s): “These images would have reminded the family of their homeland and also given restaurant customers a sense of Vietnamese culture.” The social-developmental, postcolonial agenda of My Place is registered in both “conventional” ancillary texts, such as the series’ “making of” publication (Wheatley), and the elaborate pedagogical website for teachers developed by the ACTF and Educational Services Australia (http://www.myplace.edu.au/). The politicising function of the latter is encoded in the various summaries of each decade’s historical, political, social, cultural, and technological highlights, often associated with the plot of the relevant episode. The page titled “Multiculturalism” reports on the positive amendments to the Commonwealth’s Migration Act 1958 and provides links to photographs of Vietnamese migrants in 1982, exemplifying the values of equality and cultural diversity through Lily and Phuong’s story. The detailed “Teaching Activities” documents available for each episode serve a similar purpose, providing, for example, the suggestion that teachers “ask students to discuss the importance to a new immigrant of retaining links to family, culture and tradition.” The empathetic positioning of Phuong’s situation is further mirrored in the interactive map available for teacher use that enables children to navigate a boat from Vietnam to the Australian coast, encouraging a perspective that is rarely put forward in Australia’s mass media. This is not to suggest that the My Place project is entirely unproblematic. In her postcolonial analysis of Aboriginal children’s literature, Clare Bradford argues that “it’s all too possible for ‘similarities’ to erase difference and the political significances of [a] text” (188). Lily’s schoolteacher’s lesson in the episode “reminds us that boat people have been coming to Australia for a very long time.” However, the implied connection between convicts and asylum seekers triggered by Phuong’s (mis)understanding awkwardly appropriates a mythologised Australian history. Similarly in the “1998” episode, the Muslim character Mohammad’s use of Ramadan for personal strength in order to emulate the iconic Australian cricketer Shane Warne threatens to subsume the “difference” of the diasporic community. Nonetheless, alongside the similarities between individuals and the various ethnic groups that make up the My Place community, important distinctions remain. Each episode begins and/or ends with the child protagonist(s) playing on or around the central motif of the series—a large fig tree—with the characters declaring that the tree is “my place.” While emphasising the importance of individuality in the project’s construction of child citizens, the cumulative effect of these “my place” sentiments, felt over time by characters from different socio-economic, ethnic, and cultural backgrounds, builds a multifaceted conception of Australian identity that consists of numerous (and complementary) “branches.” The project’s multi-platformed content further emphasises this, with the website containing an image of the prominent (literal and figurative) “Community Tree,” through which the viewser can interact with the generations of characters and families from the series (http://www.abc.net.au/abc3/myplace/). The significant role of the ABC’s My Place project showcases the ABC’s remit as a public broadcaster in the digital era. As Tim Brooke-Hunt, the Executive Head of Children’s Content, explains, if the ABC didn’t do it, no other broadcaster was going to come near it. ... I don’t expect My Place to be a humungous commercial or ratings success, but I firmly believe ... that it will be something that will exist for many years and will have a very special place. Conclusion The reversion to iconic aspects of mainstream Anglo-Australian culture is perhaps unsurprising—and certainly telling—when reflecting on the network of local, national, and global forces impacting on the development of a cultural commons. However, this does not detract from the value of the public broadcaster’s construction of child citizens within a clearly self-conscious discourse of “multiculturalism.” The transmedia intertextuality at work across ABC3 projects and platforms serves an important politicising function, offering positive representations of diasporic communities to counter the negative depictions children are exposed to elsewhere, and positioning child viewsers to “participate” in “working through” fraught issues of Australia’s past that still remain starkly relevant today.References ABC. Redefining the Town Square. ABC Annual Report. Sydney: ABC, 2009. Bennett, James, and Niki Strange. “The BBC’s Second-Shift Aesthetics: Interactive Television, Multi-Platform Projects and Public Service Content for a Digital Era.” Media International Australia: Incorporating Culture and Policy 126 (2008): 106-19. Born, Georgina. Uncertain Vision: Birt, Dyke and the Reinvention of the BBC. London: Vintage, 2004. boyd, danah. “Why Youth ♥ Social Network Sites: The Role of Networked Publics in Teenage Social Life.” Youth, Identity, and Digital Media. Ed. David Buckingham. Cambridge: MIT, 2008. 119-42. Bradford, Clare. Reading Race: Aboriginality in Australian Children’s Literature. Carlton: Melbourne UP, 2001. Brooke-Hunt, Tim. Executive Head of Children’s Content, ABC TV. Interviewed by Dr Leonie Rutherford, ABC Ultimo Center, 16 Mar. 2010. Buckingham, David. After the Death of Childhood: Growing Up in the Age of Electronic Media. Cambridge: Polity, 2000. Buckland, Jenny. Chief Executive Officer, Australian Children’s Television Foundation. Interviewed by Dr Leonie Rutherford and Dr Nina Weerakkody, ACTF, 2 June 2010. Caldwell, John T. “Second Shift Media Aesthetics: Programming, Interactivity and User Flows.” New Media: Theories and Practices of Digitextuality. Eds. John T. Caldwell and Anna Everett. London: Routledge, 2003. 127-44. Debrett, Mary. “Riding the Wave: Public Service Television in the Multiplatform Era.” Media, Culture & Society 31.5 (2009): 807-27. From, Unni. “Domestically Produced TV-Drama and Cultural Commons.” Cultural Dilemmas in Public Service Broadcasting. Eds. Gregory Ferrell Lowe and Per Jauert. Göteborg: Nordicom, 2005. 163-77. Glen, David. Executive Producer, ABC Multiplatform. Interviewed by Dr Leonie Rutherford, ABC Elsternwick, 6 July 2010. Harries, Dan. “Watching the Internet.” The New Media Book. Ed. Dan Harries. London: BFI, 2002. 171-82. Murdock, Graham. “Building the Digital Commons: Public Broadcasting in the Age of the Internet.” Cultural Dilemmas in Public Service Broadcasting. Ed. Gregory Ferrell Lowe and Per Jauert. Göteborg: Nordicom, 2005. 213–30. My Place, Volumes 1 & 2: 2008–1888. DVD. ABC, 2009. Northam, Jean A. “Rehearsals in Citizenship: BBC Stop-Motion Animation Programmes for Young Children.” Journal for Cultural Research 9.3 (2005): 245-63. Wheatley, Nadia. Making My Place. Sydney and Auckland: HarperCollins, 2010. ———, and Donna Rawlins. My Place, South Melbourne: Longman, 1988.