4,975 research outputs found

    Deep Adaptive Attention for Joint Facial Action Unit Detection and Face Alignment

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    Facial action unit (AU) detection and face alignment are two highly correlated tasks since facial landmarks can provide precise AU locations to facilitate the extraction of meaningful local features for AU detection. Most existing AU detection works often treat face alignment as a preprocessing and handle the two tasks independently. In this paper, we propose a novel end-to-end deep learning framework for joint AU detection and face alignment, which has not been explored before. In particular, multi-scale shared features are learned firstly, and high-level features of face alignment are fed into AU detection. Moreover, to extract precise local features, we propose an adaptive attention learning module to refine the attention map of each AU adaptively. Finally, the assembled local features are integrated with face alignment features and global features for AU detection. Experiments on BP4D and DISFA benchmarks demonstrate that our framework significantly outperforms the state-of-the-art methods for AU detection.Comment: This paper has been accepted by ECCV 201

    Vertex importance extension of betweenness centrality algorithm

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    Variety of real-life structures can be simplified by a graph. Such simplification emphasizes the structure represented by vertices connected via edges. A common method for the analysis of the vertices importance in a network is betweenness centrality. The centrality is computed using the information about the shortest paths that exist in a graph. This approach puts the importance on the edges that connect the vertices. However, not all vertices are equal. Some of them might be more important than others or have more significant influence on the behavior of the network. Therefore, we introduce the modification of the betweenness centrality algorithm that takes into account the vertex importance. This approach allows the further refinement of the betweenness centrality score to fulfill the needs of the network better. We show this idea on an example of the real traffic network. We test the performance of the algorithm on the traffic network data from the city of Bratislava, Slovakia to prove that the inclusion of the modification does not hinder the original algorithm much. We also provide a visualization of the traffic network of the city of Ostrava, the Czech Republic to show the effect of the vertex importance adjustment. The algorithm was parallelized by MPI (http://www.mpi-forum.org/) and was tested on the supercomputer Salomon (https://docs.it4i.cz/) at IT4Innovations National Supercomputing Center, the Czech Republic.808726

    An Edgeworth expansion for finite population L-statistics

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    In this paper, we consider the one-term Edgeworth expansion for finite population L-statistics. We provide an explicit formula for the Edgeworth correction term and give sufficient conditions for the validity of the expansion which are expressed in terms of the weight function that defines the statistics and moment conditions.Comment: 14 pages. Minor revisions. Some explanatory comments and a numerical example were added. Lith. Math. J. (to appear

    Characterization of the model for experimental testicular teratoma in 129/SvJ-mice

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    An animal model of experimental testicular teratoma has been established to study how a teratoma affects the host testis and how the host testis reacts against the teratoma. 129/SvJ-mice were used as experimental animals. To induce the experimental testicular teratoma, male gonadal ridges from 12-day-old 129/SvJ-mouse fetuses were grafted into the testes of adult mice for 1-12 weeks. The developing tumour was analysed by light and electron microscopy and by immunocytochemical localization of transcription factors SOX9 and c-kit, glial fibrillary acidic protein (GFAP) and type IV collagen. Testicular teratoma was observed in 36 out of 124 testes with implanted fetal gonadal ridges (frequency 29%). One spontaneous testicular teratoma was observed in this material from 70 male mice (1.5%). One week after implantation intracordal clusters of cells were seen in embryonic testicular cords of the graft as the first sign of testicular teratomas. Four weeks after implantation the embryonic testicular cords had totally disappeared from grafts with teratomas, and the tumour tissue had enlarged the testis and invaded the interstitium of the host testis. It consisted of solitary pieces of immature cartilage as well as of glial cells and of primitive neuroepithelium. Six to eight weeks after implantation the tumour tissue had expanded so that the enlarged testis could be detected by macroscopic enlargement of the scrotum. The testicular tissue of the host had practically disappeared, and only solitary disrupted seminiferous tubules of the host were seen surrounding the teratoma. Neuroepithelial structures of some teratomas cultured for 8 weeks had cells with a granular nucleus as a sign of obvious apoptosis. Eleven to 12 weeks after implantation the growth of the teratoma had stopped, and the histology corresponded to that of a mature cystic teratoma. GFAP, SOX9 and type IV collagen were strongly positive in some parts of the tumours cultured for 4 and 8 weeks, while only occasional c-kit-positive areas were observed in tumours cultured for 8 weeks. As conclusions: (1) the metastasizing capacity of the experimental testicular teratoma is very low during 12 weeks, but the behaviour of the tumour in the testicular tissue of the graft is invasive; (2) the growth of experimental testicular teratomas cease 6-8 weeks after implantation of the fetal gonadal ridges with the obvious apoptosis of the immature tissue components; (3) the model of experimental testicular teratoma in the mouse is suitable for studying how the teratoma affects the host testis and how the host testis reacts to teratoma

    Is organic food becoming less safe? A longitudinal analysis of conventional and organic product recalls

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    Organic products are often portrayed as a healthy alternative—grown in a sustainable way, often locally and subject to external certification scrutiny. However, recent high-profile cases of contaminated organic food have raised questions about the risks associated with organic produce: is organic produce becoming less safe and more risky? The context for this investigation is in the realm of food product recalls. Based on 2010–2017 panel data from the US on food product recalls (with 2721 observations), this paper compares the volume of recalls (adjusted for the growth of sales) between conventional and organic food. This paper further addresses two food-related risks: design risk (a risk that is present in the development of food; such as the use of unapproved ingredients or the omission of some ingredients on the food label) and process risk (a risk within the supply chain, such as the contamination of food products with salmonella or E. coli). Further comparison is drawn based on food product type (here the paper distinguishes between processed and unprocessed food). The paper demonstrates that organic products are becoming less safe and that organic products are recalled at a higher rate. In comparison to conventional produce, organic produce is more prone to process risk and far less to design risk. Similar conclusions are reached even when the organic produce is analysed from a product type perspective

    Modulation of enhancer looping and differential gene targeting by Epstein-Barr virus transcription factors directs cellular reprogramming

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    Epstein-Barr virus (EBV) epigenetically reprogrammes B-lymphocytes to drive immortalization and facilitate viral persistence. Host-cell transcription is perturbed principally through the actions of EBV EBNA 2, 3A, 3B and 3C, with cellular genes deregulated by specific combinations of these EBNAs through unknown mechanisms. Comparing human genome binding by these viral transcription factors, we discovered that 25% of binding sites were shared by EBNA 2 and the EBNA 3s and were located predominantly in enhancers. Moreover, 80% of potential EBNA 3A, 3B or 3C target genes were also targeted by EBNA 2, implicating extensive interplay between EBNA 2 and 3 proteins in cellular reprogramming. Investigating shared enhancer sites neighbouring two new targets (WEE1 and CTBP2) we discovered that EBNA 3 proteins repress transcription by modulating enhancer-promoter loop formation to establish repressive chromatin hubs or prevent assembly of active hubs. Re-ChIP analysis revealed that EBNA 2 and 3 proteins do not bind simultaneously at shared sites but compete for binding thereby modulating enhancer-promoter interactions. At an EBNA 3-only intergenic enhancer site between ADAM28 and ADAMDEC1 EBNA 3C was also able to independently direct epigenetic repression of both genes through enhancer-promoter looping. Significantly, studying shared or unique EBNA 3 binding sites at WEE1, CTBP2, ITGAL (LFA-1 alpha chain), BCL2L11 (Bim) and the ADAMs, we also discovered that different sets of EBNA 3 proteins bind regulatory elements in a gene and cell-type specific manner. Binding profiles correlated with the effects of individual EBNA 3 proteins on the expression of these genes, providing a molecular basis for the targeting of different sets of cellular genes by the EBNA 3s. Our results therefore highlight the influence of the genomic and cellular context in determining the specificity of gene deregulation by EBV and provide a paradigm for host-cell reprogramming through modulation of enhancer-promoter interactions by viral transcription factors

    Clinical Implication of Targeting of Cancer Stem Cells

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    The existence of cancer stem cells (CSCs) is receiving increasing interest particularly due to its potential ability to enter clinical routine. Rapid advances in the CSC field have provided evidence for the development of more reliable anticancer therapies in the future. CSCs typically only constitute a small fraction of the total tumor burden; however, they harbor self-renewal capacity and appear to be relatively resistant to conventional therapies. Recent therapeutic approaches aim to eliminate or differentiate CSCs or to disrupt the niches in which they reside. Better understanding of the biological characteristics of CSCs as well as improved preclinical and clinical trials targeting CSCs may revolutionize the treatment of many cancers. Copyright (c) 2012 S. Karger AG, Base

    Effects of two common polymorphisms in the 3' untranslated regions of estrogen receptor β on mRNA stability and translatability

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    Estrogen signaling is mediated by estrogen receptors (ERs), ERα and ERβ. Aberrant estrogen signaling is involved in breast cancer development. ERα is one of the key biomarkers for diagnosis and treatment of breast cancer. Unlike ERα, ERβ is still not introduced as a marker for diagnosis and established as a target of therapy. Numerous studies suggest antiproliferative effects of ERβ, however its role remains to be fully explored. Albeit important, ERα is not a perfect marker, and some aspects of ERα function are still unclear. This thesis aims to characterize distinct molecular facets of ER action relevant for breast cancer and provide valuable information for ER-based diagnosis and treatment design. In PAPER I, we analyzed the functionality of two common single nucleotide polymorphisms in the 3’ untranslated regions of ERβ, rs4986938 and rs928554, which have been extensively investigated for association with various diseases. A significant difference in allelic expression was observed for rs4986938 in breast tumor samples from heterozygous individuals. However, no difference in mRNA stability or translatability between the alleles was observed. In PAPER II, we provided a more comprehensive understanding of ERβ function independent of ERα. A global gene expression analysis in a HEK293/ERβ cell model identified a set of ERβ-regulated genes. Gene Ontology (GO) analysis showed that they are involved in cell-cell signaling, morphogenesis and cell proliferation. Moreover, ERβ expression resulted in a significant decrease in cell proliferation. In PAPER III, using the human breast cancer MCF-7/ERβ cell model, we demonstrated, for the first time, the binding of ERα/β heterodimers to various DNA-binding regions in intact chromatin. In PAPER IV, we investigated a potential cross-talk between estrogen signaling and DNA methylation by identifying their common target genes in MCF-7 cells. Gene expression profiling identified around 150 genes regulated by both 17β- estradiol (E2) and a hypomethylating agent 5-aza-2’-deoxycytidine. Based on GO analysis, CpG island prediction analysis and previously reported ER binding regions, we selected six genes for further analysis. We identified BTG3 and FHL2 as direct target genes of both pathways. However, our data did not support a direct molecular interplay of mediators of estrogen and epigenetic signaling at promoters of regulated genes. In PAPER V, we further explored the interactions between estrogen signaling and DNA methylation, with focus on DNA methyltransferases (DNMT1, DNMT3a and DNMT3b). E2, via ERα, up-regulated DNMT1 and down-regulated DNMT3a and DNMT3b mRNA expression. Furthermore, DNMT3b interacted with ERα. siRNA-mediated DNMT3b depletion increased the expression of two genes, CDKN1A and FHL2. We proposed that the molecular mechanism underlying regulation of FHL2 and CDKN1A gene expression involves interplay of DNMT3b and ERα. In conclusion, the studies presented in this thesis contribute to the knowledge of ERβ function, and give additional insight into the cross-talk mechanisms underlying ERα signaling with ERβ and with DNA methylation pathways

    Rhesus TRIM5α disrupts the HIV-1 capsid at the inter-hexamer interfaces

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    TRIM proteins play important roles in the innate immune defense against retroviral infection, including human immunodeficiency virus type-1 (HIV-1). Rhesus macaque TRIM5α (TRIM5αrh) targets the HIV-1 capsid and blocks infection at an early post-entry stage, prior to reverse transcription. Studies have shown that binding of TRIM5α to the assembled capsid is essential for restriction and requires the coiled-coil and B30.2/SPRY domains, but the molecular mechanism of restriction is not fully understood. In this study, we investigated, by cryoEM combined with mutagenesis and chemical cross-linking, the direct interactions between HIV-1 capsid protein (CA) assemblies and purified TRIM5αrh containing coiled-coil and SPRY domains (CC-SPRYrh). Concentration-dependent binding of CC-SPRYrh to CA assemblies was observed, while under equivalent conditions the human protein did not bind. Importantly, CC-SPRYrh, but not its human counterpart, disrupted CA tubes in a non-random fashion, releasing fragments of protofilaments consisting of CA hexamers without dissociation into monomers. Furthermore, such structural destruction was prevented by inter-hexamer crosslinking using P207C/T216C mutant CA with disulfide bonds at the CTD-CTD trimer interface of capsid assemblies, but not by intra-hexamer crosslinking via A14C/E45C at the NTD-NTD interface. The same disruption effect by TRIM5αrh on the inter-hexamer interfaces also occurred with purified intact HIV-1 cores. These results provide insights concerning how TRIM5α disrupts the virion core and demonstrate that structural damage of the viral capsid by TRIM5α is likely one of the important components of the mechanism of TRIM5α-mediated HIV-1 restriction. © 2011 Zhao et al
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