436 research outputs found

    Role of enhancer of zeste homolog 2 polycomb protein and its significance in tumor progression and cell differentiation

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    Epigenetics is a branch of genetics that focuses on the heritable changes of DNA or associated proteins, other than DNA sequence variations, which carry information content during cell division [1,2]. These heritable changes are ascribed to chromatin, which constitutes the ultrastructure of DNA and whose modifications affect the genetic material functionality. Differences in chromatin structure have been associated to transcription regulation [3-5] and chromosome stability [6,7], affecting both gene’s information, expression and heritability. Noteworthy, these epigenetic modifications are involved in both transcriptional activation and repression, indicating their widespread role as modulators of gene expression in numerous biological processes [8,9]. Chromatin is subjected to numerous modifications roughly classified in two groups: DNA and histone post-translational modifications (histone-PTMs). DNA methylation is the most studied epigenetic modification of DNA and corresponds to the covalent addition of a methyl (CH3) group to the nucleotide cytosine within CG dinucleotides or CNG trinucleotides where N can be C, A, G or T. Usually, DNA methylation induces decreased protein-DNA binding of transcription factors and leads to the repression of gene expression [10]. DNA “methylable” sequences are not uniform across the human genome but restricted in CpG rich DNA regions termed CpG islands (CGI). CGI are localized at repetitive sequences, heavy methylated, to prevent the reactivation of endoparasitic sequences such as transposons, and at gene promoter sequences, which are normally refractory to methylation in normal somatic cells [8,11].</br

    Identifying the 3FHL catalog: I. Results of the KOSMOS optical spectroscopy campaign

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    We present the results of the optical spectroscopy follow-up of a sample of 28 unclassified blazars from the Third Fermi-LAT Catalog of High-Energy Sources (3FHL). All the spectra were taken with the 4m Mayall telescope at Kitt Peak. With this follow-up program we are able to classify 27 out of 28 objects as BL Lacs, while the remaining one is a flat spectrum radio quasar. We determine a redshift (z) for three of these objects and a lower limit on z for other four sources: the farthest object for which we obtain a redshift has z>0.836. These results are part of a more extended campaign of optical spectroscopy follow-up of 3FHL blazars, aimed to obtain a complete sample of blazars at >10 GeV which will then be used to extend our knowledge on blazar emission mechanisms and on the extragalactic background light.Comment: 12 pages, 6 figures. Accepted for publication on the Astronomical Journal Supplement Series. The spectra analyzed in this work are available at the following link: https://clemson.app.box.com/s/uu1hk6g4qy0ow9j4nst4nifm3mmrs19

    Fast wavelet transform assisted predictors of streaming time series

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    Abstract We explore the shift variance of the decimated, convolutional Discrete Wavelet Transform, also known as Fast Wavelet Transform. We prove a novel theorem improving the FWT algorithm and implement a new prediction method suitable to the multiresolution analysis of streaming univariate datasets using compactly supported Daubechies Wavelets. An effective real value forecast is obtained synthesizing the one step ahead crystal and performing its inverse DWT, using an integrated group of estimating machines. We call Wa.R.P. (Wavelet transform Reduced Predictor) the new prediction method. A case study, testing a cryptocurrency exchange price series, shows that the proposed system can outperform the benchmark methods in terms of forecasting accuracy achieved. This result is confirmed by further tests performed on other time series. Developed in C++, Standard 2014 conformant, the code implementing the FWT and the novel Shift Variance Theorem is available to research purposes and to build efficient industrial applications

    Monitoraggio dei flussi migratori nel Mar Mediterraneo con satelliti ottici e SAR

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    Il Mediterraneo è sempre stato considerato un’area di intensi scambi politici, economici e culturali, ma nell’ultimo decennio è diventato anche luogo di intensi flussi migratori dal Nordafrica verso l’Europa. L’immigrazione illegale via mare ha ormai assunto una dimensione tale che nei soli primi due mesi del 2016 oltre 110.000 migranti hanno attraversato il Mediterraneo (fonte: UNHCR). Alla luce di questi numeri, in continua crescita, le istituzioni europee stanno cercando nuove soluzioni per rafforzare il monitoraggio dei confini esterni dell’Unione Europea. Tale operazione, che coinvolge un’area geografica molto estesa, risulta però complessa e costosa se svolta solamente con i mezzi tradizionali (radar di terra, mezzi aerei e navali). In questo contesto, il progetto Space Shepherd cofinanziato dal Politecnico di Milano nell’ambito del programma Polisocial Award, si è occupato dello studio di fattibilità di un sistema integrato ottico-radar per l’individuazione, il monitoraggio e il tracciamento d’imbarcazioni sconosciute in navigazione nel Mar Mediterraneo utilizzando asset speziali già esistenti (Topputo et al., 2015b). L’utilizzo congiunto d’immagini ottiche e radar è in grado di garantire un’osservazione continua e non dipendente dalle condizioni atmosferiche o di illuminazione e una complementarietà in termini di copertura geografica e dettaglio geometrico

    Smart Contracts Software Metrics: a First Study

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    © 2018 The Author(s).Smart contracts (SC) are software codes which reside and run over a blockchain. The code can be written in different languages with the common purpose of implementing various kinds of transactions onto the hosting blockchain, They are ruled by the blockchain infrastructure and work in order to satisfy conditions typical of traditional contracts. The software code must satisfy constrains strongly context dependent which are quite different from traditional software code. In particular, since the bytecode is uploaded in the hosting blockchain, size, computational resources, interaction between different parts of software are all limited and even if the specific software languages implement more or less the same constructs of traditional languages there is not the same freedom as in normal software development. SC software is expected to reflect these constrains on SC software metrics which should display metric values characteristic of the domain and different from more traditional software metrics. We tested this hypothesis on the code of more than twelve thousands SC written in Solidity and uploaded on the Ethereum blockchain. We downloaded the SC from a public repository and computed the statistics of a set of software metrics related to SC and compared them to the metrics extracted from more traditional software projects. Our results show that generally Smart Contracts metrics have ranges more restricted than the corresponding metrics in traditional software systems. Some of the stylized facts, like power law in the tail of the distribution of some metrics, are only approximate but the lines of code follow a log normal distribution which reminds of the same behavior already found in traditional software systems.Submitted Versio

    Advanced Technologies for Human-Computer Interfaces in Mixed Reality

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    As human beings, we trust our five senses, that allow us to experience the world and communicate. Since our birth, the amount of data that every day we can acquire is impressive and such a richness reflects the complexity of humankind in arts, technology, etc. The advent of computers and the consequent progress in Data Science and Artificial Intelligence showed how large amounts of data can contain some sort of “intelligence” themselves. Machines learn and create a superimposed layer of reality. How data generated by humans and machines are related today? To give an answer we will present three projects in the context of “Mixed Reality”, the ideal place where Reality, Virtual Reality and Augmented Reality are increasingly connected as long as data enhance the digital experiences, making them more “real”. We will start with BRAVO, a tool that exploits the brain activity to improve the user’s learning process in real time by means of a Brain-Computer Interface that acquires EEG data. Then we will see AUGMENTED GRAPHICS, a framework for detecting objects in the reality that can be captured easily and inserted in any digital scenario. Based on the moments invariants theory, it looks particularly designed for mobile devices, as it assumes a light concept of object detection and it works without any training set. As third work, GLOVR, a wearable hand controller that uses inertial sensors to offer directional controls and to recognize gestures, particularly suitable for Virtual Reality applications. It features a microphone to record voice sequences that then are translated in tasks by means of a natural language web service. For each project we will summarize the main results and we will trace some future directions of research and development
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