Αναγνώριση Συναισθήματος με χρήση Βαθιάς Μάθησης και Πρωτότυπων Τεχνικών Επαύξησης Δεδομένων

υγκεκριμένα task. Γενικά, το συναίσθημα ενός ανθρώπου αναγνωρίζεται αναλύοντας εκφράσεις του προσώπου, χειρονομίες, τη στάση του σώματος, την ομιλία ή φυσιολογικές παραμέτρους όπως αυτές προκύπτουν από ηλεκτροεγκεφαλογραφήματα, ηλεκτροκαρδιογραφήματα κα. Ωστόσο, σε πολλές περιπτώσεις οι οπτικές πληροφορίες δεν διαθέσιμες ή κατάλληλες, ενώ η μέτρηση των φυσιολογικών παραμέτρων είναι δύσκολη, δύσχρηστη και απαιτεί εξειδικευμένο ακριβό εξοπλισμό. Συνεπώς, η ομιλία ίσως είναι η καλύτερη εναλλακτική. Οι συνηθισμένες τεχνικές μηχανικής μάθησης που χρησιμοποιούνται για το σκοπό αυτό εξάγουν ένα σύνολο γλωσσολογικών χαρακτηριστικών από τα δεδομένα, τα οποία χρησιμοποιούνται στη συνέχεια για την εκπαίδευση μοντέλων επιβλεπόμενης μάθησης (supervised learning). Στη διπλωματική αυτή χρησιμοποιείται ένα μοντέλο Συνελικτικού Νευρωνικού Δικτύου (Convolution Neural Network - CNN) που σε αντίθεση με τις παραδοσιακές προσεγγίσεις ανιχνεύει μόνο τα σημαντικά χαρακτηριστικά των δεδομένων που εισάγονται σε αυτό. Αξίζει να σημειωθεί, πως η αρχιτεκτονική ενός CNN είναι ανάλογη με τη συνδεσιμότητα των νευρώνων του ανθρώπινου εγκεφάλου και εμπνευσμένη από την οργάνωση του οπτικού φλοιού. Χρησιμοποιούνται τρια σύνολα ηχητικών δεδομένων (EMOVO, SAVEE, Emo-DB), από όπου εξάγονται τα αντίστοιχα φασματογραφηματα (spectrograms), τα οποία με τη σειρά τους χρησιμοποιούνται ως είσοδοι στο νευρωνικό δίκτυο. Για τη βέλτιστη απόδοση του αλγορίθμου εφαρμόζονται πρωτότυπες τεχνικές επαύξησης (data augmentation) των αρχικών δεδομένων πέραν της συνηθισμένης πρόσθεσης noise, όπως μετατόπιση του ηχητικού σήματος, αλλαγή της οξύτητας και της ταχύτητας του. Τέλος, χρησιμοποιούνται μέθοδοι καταπολέμησης της υπερπροσαρμογής (overfitting) όπως το dropout και τεχνικές ενίσχυσης της γενικευσιμότητας του μοντέλου όπως πρόσθεση επιπέδων κανονικοποίησης τοπικής απόκρισης (local response normalization layers), η λειτουργία των οποίων είναι εμπνευσμένη από την πλευρική αναστολή (lateral inhibition) των νευρώνων του εγκεφάλου. Τα αποτελέσματα είναι βελτιωμένα σε σχέση με άλλες παρόμοιες μελέτες. Ωστόσο, το μοντέλο δεν υποδεικνύει ανεξαρτησία από τη γλώσσα των ηχητικών σημάτων.Emotion recognition is quite important for various applications related to human-computer interaction or for understanding the user's mood in specific tasks. In general, a person's emotion is recognized by analyzing facial expressions, gestures, posture, speech or physiological parameters such as those occurring from electroencephalograms, electrocardiograms, etc. However, in many cases, the visual information is not available or appropriate, while the measurement of physiological parameters is difficult and requires specialized, expensive equipment. As a result, speech is probably the best alternative. The typical machine learning techniques used for this purpose extract a set of linguistic features from the data, which are then used to train supervised learning models. In this thesis, a Convolution Neural Network (CNN) is proposed, which, unlike traditional approaches, detects only the important features of raw data entered into it. It is worth noting that the architecture of a CNN is analogous to the connectivity of the neurons of the human brain and inspired by the organization of the visual cortex. The inputs to the neural network are the spectrograms that are extracted from audio signals. For the optimal performance of the algorithm, data augmentation techniques of the original data are applied such as adding noise, shifting of the audio signal, and changing its pitch or its speed. Finally, methods against overfitting are applied, such as dropout and local response normalization layers, the operation of which is inspired by lateral inhibition of the neurons of the human brain. Our approach outperformed previous work, without being established as a considerably language-independent one

The use of premature chromosome condensation to study in interphase cells the influence of environmental factors on human genetic material

Nowadays, there is a constantly increasing concern regarding the mutagenic and carcinogenic potential of a variety of harmful environmental factors to which humans are exposed in their natural and anthropogenic environment. These factors exert their hazardous potential in humans' personal (diet, smoking, pharmaceuticals, cosmetics) and occupational environment that constitute part of the anthropogenic environment. It is well known that genetic damage due to these factors has dramatic implications for human health. Since most of the environmental genotoxic factors induce arrest or delay in cell cycle progression, the conventional analysis of chromosomes at metaphase may underestimate their genotoxic potential. Premature Chromosome Condensation (PCC) induced either by means of cell fusion or specific chemicals, enables the microscopic visualization of interphase chromosomes whose morphology depends on the cell cycle stage, as well as the analysis of structural and numerical aberrations at the G1 and G2 phases of the cell cycle. The PCC has been successfully used in problems involving cell cycle analysis, diagnosis and prognosis of human leukaemia, assessment of interphase chromosome malformations resulting from exposure to radiation or chemicals, as well as elucidation of the mechanisms underlying the conversion of DNA damage into chromosomal damage. In this report, particular emphasis is given to the advantages of the PCC methodology used as an alternative to conventional metaphase analysis in answering questions in the fields of radiobiology, biological dosimetry, toxicogenetics, clinical cytogenetics and experimental therapeutics

The International Virus Bioinformatics Meeting 2020.

The International Virus Bioinformatics Meeting 2020 was originally planned to take place in Bern, Switzerland, in March 2020. However, the COVID-19 pandemic put a spoke in the wheel of almost all conferences to be held in 2020. After moving the conference to 8-9 October 2020, we got hit by the second wave and finally decided at short notice to go fully online. On the other hand, the pandemic has made us even more aware of the importance of accelerating research in viral bioinformatics. Advances in bioinformatics have led to improved approaches to investigate viral infections and outbreaks. The International Virus Bioinformatics Meeting 2020 has attracted approximately 120 experts in virology and bioinformatics from all over the world to join the two-day virtual meeting. Despite concerns being raised that virtual meetings lack possibilities for face-to-face discussion, the participants from this small community created a highly interactive scientific environment, engaging in lively and inspiring discussions and suggesting new research directions and questions. The meeting featured five invited and twelve contributed talks, on the four main topics: (1) proteome and RNAome of RNA viruses, (2) viral metagenomics and ecology, (3) virus evolution and classification and (4) viral infections and immunology. Further, the meeting featured 20 oral poster presentations, all of which focused on specific areas of virus bioinformatics. This report summarizes the main research findings and highlights presented at the meeting

SARS-CoV-2 lineage B.1.1.7 is associated with greater disease severity among hospitalised women but not men: multicentre cohort study.

BACKGROUND: SARS-CoV-2 lineage B.1.1.7 has been associated with an increased rate of transmission and disease severity among subjects testing positive in the community. Its impact on hospitalised patients is less well documented. METHODS: We collected viral sequences and clinical data of patients admitted with SARS-CoV-2 and hospital-onset COVID-19 infections (HOCIs), sampled 16 November 2020 to 10 January 2021, from eight hospitals participating in the COG-UK-HOCI study. Associations between the variant and the outcomes of all-cause mortality and intensive therapy unit (ITU) admission were evaluated using mixed effects Cox models adjusted by age, sex, comorbidities, care home residence, pregnancy and ethnicity. FINDINGS: Sequences were obtained from 2341 inpatients (HOCI cases=786) and analysis of clinical outcomes was carried out in 2147 inpatients with all data available. The HR for mortality of B.1.1.7 compared with other lineages was 1.01 (95% CI 0.79 to 1.28, p=0.94) and for ITU admission was 1.01 (95% CI 0.75 to 1.37, p=0.96). Analysis of sex-specific effects of B.1.1.7 identified increased risk of mortality (HR 1.30, 95% CI 0.95 to 1.78, p=0.096) and ITU admission (HR 1.82, 95% CI 1.15 to 2.90, p=0.011) in females infected with the variant but not males (mortality HR 0.82, 95% CI 0.61 to 1.10, p=0.177; ITU HR 0.74, 95% CI 0.52 to 1.04, p=0.086). INTERPRETATION: In common with smaller studies of patients hospitalised with SARS-CoV-2, we did not find an overall increase in mortality or ITU admission associated with B.1.1.7 compared with other lineages. However, women with B.1.1.7 may be at an increased risk of admission to intensive care and at modestly increased risk of mortality.This report was produced by members of the COG-UK-HOCI Variant substudy consortium. COG-UK-HOCI is part of COG-UK. COG-UK is supported by funding from the Medical Research Council (MRC) part of UK Research & Innovation (UKRI), the National Institute of Health Research (NIHR) and Genome Research Limited, operating as the Wellcome Sanger Institute

The use of premature chromosome condensation to study in interphase cells the influence of environmental factors on human genetic material

Nowadays, there is a constantly increasing concern regarding the mutagenic and carcinogenic potential of a variety of harmful environmental factors to which humans are exposed in their natural and anthropogenic environments. These factors exert their hazardous potential in humans' personal (diet, smoking, pharmaceuticals, cosmetics) and occupational environments that constitute part of the anthropogenic environment. It is well known that genetic damage due to these factors has dramatic implications for human health. Since most of the environmental genotoxic factors induce arrest or delay in cell cycle progression, the conventional analysis of chromosomes at metaphase may underestimate their genotoxic potential. Premature chromosome condensation (PCC) induced either by means of cell fusion or specific chemicals, enables the microscopic visualization of interphase chromosomes whose morphology depends on the cell cycle stage, as well as the analysis of structural and numerical aberrations at the G 1 and G 2 phases of the cell cycle. The PCC method has been successfully used in problems involving cell cycle analysis, diagnosis, and prognosis of human leukemia, assessment of interphase chromosome malformations resulting from exposure to radiation or chemicals, as well as elucidation of the mechanisms underlying the conversion of DNA damage into chromosomal damage. In this report, particular emphasis is given to the advantages of the PCC methodology used as an alternative to conventional metaphase analysis in order to answer questions in the fields of radiobiology, biological dosimetry, toxicogenetics, clinical cytogenetics, and experimental therapeutics. KEYWORDS: premature chromosome condensation, cell fusion, calyculin-A, lymphocytes, DNA damage, genotoxicity, sister chromatid exchanges, chromosomal damage, chromosome aberrations, cell cycle delay, chemicals, ionizing radiation Hatzi et al.: Interphase genotoxicity assessment using PCC TheScientificWorldJOURNAL (2006TheScientificWorldJOURNAL ( ) 6, 1174TheScientificWorldJOURNAL ( -1190 INTRODUCTION Nowadays, there is a constantly increasing concern regarding the mutagenic and carcinogenic potential of a variety of harmful environmental agents to which humans are exposed in their natural and anthropogenic environments. Harmful environmental agents, exerting their effect on living organisms from the beginning of life, developed the appropriate evolutionary pressure that resulted in their defense mechanisms. Human technological development as well as human lifestyle introduced new series of harmful agents that, either alone or in combination, affect humans and all other organisms. These new agents exert their hazardous potential in humans' personal (diet, smoking, pharmaceuticals, cosmetics) and occupational environments that constitute part of the anthropogenic environment. The most important consequences of human exposure to environmental hazards are DNA damage induced either by direct or indirect binding to DNA. Direct-acting chemicals like DNA alkylating agents (e.g., mitomycin-C), crosslinking agents (e.g., methyl methanesulfonate), and oxygen radicals (e.g., hydrogen peroxide), bind covalently to DNA The exposure of cells to genotoxic factors may result in changes at the chromatid level, such as sister chromatid exchanges (SCEs), as well as in structural chromosomal alterations such as chromosomal aberrations Until now, the conventional cytogenetic analysis of chromosomal damage as a result of exposure to environmental chemicals is mainly based on the microscopic analysis of chromosomes in metaphase In this report, the advantages of the PCC methodologies used as an alternative to conventional metaphase analysis or in combination with other cytogenetic techniques are reviewed. Furthermore, the use of PCC in overcoming problems that could not be solved with the conventional metaphase analysis is Hatzi et al.: Interphase genotoxicity assessment using PCC TheScientificWorldJOURNAL (2006) 6, 1174-1190 1176 presented, and particular emphasis is given to the potential use of PCC to elucidate the mechanisms underlying conversion of DNA damage into chromosomal damage. Additional applications of the PCC methodologies in the fields of radiobiology, biological dosimetry, toxicogenetics, clinical cytogenetics, and experimental therapeutics are described, and future perspectives are discussed. PCC METHODOLOGIES PCC Induction Using Cell Fusion Central for the PCC assay is the fusion of interphase "test" cells with mitotic "inducer" cells that can be mediated either by incubation with Sendai virus As an alternative to the Sendai virus, the well-known fusogen polyethylene glycol (PEG) was applied to PCC-induction procedures Using the PCC assay by means of cell fusion, interphase cells that are either cycling, noncycling, or arrested can be visualized and analyzed. In the hybrids formed by cell fusion, the mitotic factors present in the donor mitotic cell dissolve the nucleus membrane and condense chromatin of the interphase "test" cell. More specifically, cells that have undergone PCC assume a morphology that is characteristic of the position of the interphase cell in the cell cycle: single chromatid per chromosome in G 1 phase, double chromatids per chromosome in G 2 , and pulverized chromosome regions in S phase Chemically Induced PCC Chemically induced PCCs can be obtained by the use of the chemical compounds such as calyculin-A. Calyculin-A was initially isolated from the marine sponge Discodermia calyx 1177 APPLICATIONS OF PCC METHODOLOGIES Biodosimetry and Biomonitoring of Exposure to Ionizing Radiation Exposure of cells to ionizing radiation has been shown to cause a wide variety of phenomena, the most prominent of which are the induction of mutations, the induction of transformation, cell cycle arrest, and cell death. As a result, the study of phenomena elicited by radiation are of particular importance to human health and, therefore, elucidation of the underlying biochemical mechanisms and cytogenetic effects of ionizing radiation are a high priority in radiation biology research. In the field of biological dosimetry, numerous methods capable of detecting radiation-induced changes at the molecular, cytogenetic, and cellular level have been used in order to obtain absorbed dose estimates For these reasons, the PCC methodology was proposed as an alternative biodosimetric tool by Pantelias and Maillie in 1984[50] and since then it has been extensively used to assess and evaluate the induction and repair of chromosome damage after in vivo or in vitro exposure of human cells to ionizing radiation Mechanisms Underlying Conversion of DNA Damage into Chromosomal Damage Visualizing cells with conventional analysis at metaphase can give information concerning only the residual damage after exposure to genotoxic environmental factors. The analysis of such interactions is based, therefore, only on those cells that proceed to mitosis. Therefore, it is difficult to elucidate the mechanism underlying the conversion of DNA damage into chromosomal damage. With the PCC methodologies, it is possible to gain valuable information not only to understand the biochemical mechanisms that affect the conversion of DNA damage into chromosomal damage, but also to determine possibly chromosomal radiosensitivity in G 2 phase, as well as variability in radiosensitivity at various stages of the cell cycle. The Hatzi et al.: Interphase genotoxicity assessment using PCC TheScientificWorldJOURNAL (2006) 6, 1174-1190 1181 onset and the efficiency of chromatin condensation-decondensation are important determinants of these processes. Data obtained so far demonstrate the important role of cdk1/cyclin-B complex and of the G 2 checkpoint control mechanism in affecting chromatin conformation changes and conversion of DNA damage into chromosomal damage. Using the PCC method, it was realized specifically that changes in chromatin conformation soon after irradiation, presumably as a result of histone-H1 phosphorylationdephosphorylation, strongly affected the conversion of DNA lesions into visual PCC fragments. The cdk1/cyclin-B complex was originally defined as the mitosis promoting factor (MPF), identified in mitotic frog eggs as a factor capable of inducing mitosis in G 2 -phase cells. Regulation of cdk1/cyclin-B complexes at multiple levels ensures the tight regulation of the timing of mitotic entry In early reports, G 0 human lymphocytes were irradiated and analyzed at various times after fusion with mitotic CHO cells, i.e., as chromatin condensation proceeded. The yield of fragments observed was directly related to the amount of chromosome condensation allowed to take place after irradiation and inversely related to the extent of chromosome condensation at the time of irradiation. From these experiments, it was concluded that changes in chromosome conformation interfered with repair processes of DNA damage. In contrast, resting chromosomes (as G 0 lymphocytes irradiated before fusion) showed efficient repair of chromosomal damage. These results supported the hypothesis that DNA damage is converted into cytogenetic lesions and becomes observable when chromatin conformation changes occur during the cell cycle G 2 checkpoint facilitates repair of chromosomal damage, and the hypothesis that G 2 -checkpoint defects during the G 2 -to M-phase transition can also affect G 2 -chromosomal sensitivity. This was tested using caffeine to abolish G 2 checkpoint by inhibiting ATM protein (Ataxia Telangiectasia mutated protein) Concerning the variability of radiosensitivity to ionizing radiation at various stages of the cell cycle, it is already known that middle to S phase and G 1 phase are resistant stages, while mitosis, G 1 /S, and G 2 /M transition are very sensitive to radiation Genotoxicity of Exposure to Chemical Agents It is well known that increased rates of cell proliferation can escalate the risk of malignancy following exposures to chemical agents 1183 The Uses of PCC in Clinical Cytogenetics and Experimental Therapeutics The fact that chromosomal analysis by means of the PCC method requires a small amount (0.5 ml or less) of sample (i.e., peripheral blood or bone marrow) makes it especially suitable for in vivo and in vitro studies, and also in clinical applications for diagnostic purposes. In particular, the ability to visualize the interphase chromosomes of bone marrow and blood cells using PCC by means of mitotic cell fusion with interphase cells has proved useful and accurate in the study of human acute leukemia Recently, calyculin-A-induced PCC has been combined with multicolor FISH [pq-COBRA-FISH (COmbined Binary RAtio labeling-fluorescence in situ hybridization)] for the cytogenetic analysis of cancer cell lines In the field of prenatal diagnosis, preliminary attempts have been made to combine calyculin-Ainduced PCC with GTG banding for fetus examination Furthermore, a major area of experimental therapeutic research centers on the function of anticancer drugs. In this field, the PCC methodology has been applied to study the effect of several anticancer drugs, such as BCNU, CCNU, Cis-acid, VM-26, adriamycin, and neocarzinostatin, whose mode of action depends on cell cycle arres

The International Virus Bioinformatics Meeting 2020.

The International Virus Bioinformatics Meeting 2020 was originally planned to take place in Bern, Switzerland, in March 2020. However, the COVID-19 pandemic put a spoke in the wheel of almost all conferences to be held in 2020. After moving the conference to 8-9 October 2020, we got hit by the second wave and finally decided at short notice to go fully online. On the other hand, the pandemic has made us even more aware of the importance of accelerating research in viral bioinformatics. Advances in bioinformatics have led to improved approaches to investigate viral infections and outbreaks. The International Virus Bioinformatics Meeting 2020 has attracted approximately 120 experts in virology and bioinformatics from all over the world to join the two-day virtual meeting. Despite concerns being raised that virtual meetings lack possibilities for face-to-face discussion, the participants from this small community created a highly interactive scientific environment, engaging in lively and inspiring discussions and suggesting new research directions and questions. The meeting featured five invited and twelve contributed talks, on the four main topics: (1) proteome and RNAome of RNA viruses, (2) viral metagenomics and ecology, (3) virus evolution and classification and (4) viral infections and immunology. Further, the meeting featured 20 oral poster presentations, all of which focused on specific areas of virus bioinformatics. This report summarizes the main research findings and highlights presented at the meeting

Triticum timopheevii s.l. ('new glume wheat') finds in regions of southern and eastern Europe across space and time

Triticum timopheevii sensu lato ('new glume wheat', NGW) was first recognised as a distinct prehistoric cereal crop through work on archaeobotanical finds from Neolithic and Bronze Age sites in northern Greece. This was later followed by its identification in archaeobotanical assemblages from other parts of Europe. This paper provides an overview of the currently known archaeobotanical finds of Timopheev's wheat in southeastern and eastern Europe and observes their temporal span and spatial distribution. To date, there are 89 prehistoric sites with these finds, located in different parts of the study region and dated from the Neolithic to the very late Iron Age. Their latest recorded presence in the region is in the last centuries bce. For assemblages from the site as a whole containing at least 30 grain and/or chaff remains of Timopheev's wheat, we take a brief look at the overall relative proportions of Triticum monococcum (einkorn), T. dicoccum (emmer) and T. timopheevii s.l. (Timopheev's wheat), the three most common glume wheats in our study region in prehistory. We highlight several sites where the overall proportions of Timopheev's wheat might be taken to suggest it was a minor component of a mixed crop (maslin), or an unmonitored inclusion in einkorn or emmer fields. At the same sites, however, there are also discrete contexts where this wheat is strongly predominant, pointing to its cultivation as a pure crop. We therefore emphasise the need to evaluate the relative representation of Timopheev's wheat at the level of individual samples or contexts before making inferences on its cultivation status. We also encourage re-examination of prehistoric and historic cereal assemblages for its remains

Women in the European Virus Bioinformatics Center

Viruses are the cause of a considerable burden to human, animal and plant health, while on the other hand playing an important role in regulating entire ecosystems. The power of new sequencing technologies combined with new tools for processing "Big Data" offers unprecedented opportunities to answer fundamental questions in virology. Virologists have an urgent need for virus-specific bioinformatics tools. These developments have led to the formation of the European Virus Bioinformatics Center, a network of experts in virology and bioinformatics who are joining forces to enable extensive exchange and collaboration between these research areas. The EVBC strives to provide talented researchers with a supportive environment free of gender bias, but the gender gap in science, especially in math-intensive fields such as computer science, persists. To bring more talented women into research and keep them there, we need to highlight role models to spark their interest, and we need to ensure that female scientists are not kept at lower levels but are given the opportunity to lead the field. Here we showcase the work of the EVBC and highlight the achievements of some outstanding women experts in virology and viral bioinformatics

Women in the European Virus Bioinformatics Center.

Viruses are the cause of a considerable burden to human, animal and plant health, while on the other hand playing an important role in regulating entire ecosystems. The power of new sequencing technologies combined with new tools for processing "Big Data" offers unprecedented opportunities to answer fundamental questions in virology. Virologists have an urgent need for virus-specific bioinformatics tools. These developments have led to the formation of the European Virus Bioinformatics Center, a network of experts in virology and bioinformatics who are joining forces to enable extensive exchange and collaboration between these research areas. The EVBC strives to provide talented researchers with a supportive environment free of gender bias, but the gender gap in science, especially in math-intensive fields such as computer science, persists. To bring more talented women into research and keep them there, we need to highlight role models to spark their interest, and we need to ensure that female scientists are not kept at lower levels but are given the opportunity to lead the field. Here we showcase the work of the EVBC and highlight the achievements of some outstanding women experts in virology and viral bioinformatics