211 research outputs found
DDT - Drug Discovery Tool: a fast and intuitive graphics user interface for Docking and Molecular Dynamics analysis.
Abstract
Motivation
The ligand/protein binding interaction is typically investigated by docking and molecular dynamics (MD) simulations. In particular, docking-based virtual screening (VS) is used to select the best ligands from database of thousands of compounds, while MD calculations assess the energy stability of the ligand/protein binding complexes. Considering the broad use of these techniques, it is of great demand to have one single software that allows a combined and fast analysis of VS and MD results. With this in mind, we have developed the Drug Discovery Tool (DDT) that is an intuitive graphics user interface able to provide structural data and physico-chemical information on the ligand/protein interaction.
Results
DDT is designed as a plugin for the Visual Molecular Dynamics (VMD) software and is able to manage a large number of ligand/protein complexes obtained from AutoDock4 (AD4) docking calculations and MD simulations. DDT delivers four main outcomes: i) ligands ranking based on an energy score; ii) ligand ranking based on a ligands' conformation cluster analysis; iii) identification of the aminoacids forming the most occurrent interactions with the ligands; iv) plot of the ligands' center-of-mass coordinates in the Cartesian space. The flexibility of the software allows saving the best ligand/protein complexes using a number of user-defined options.
Availability and implementation
DDT_site_1 (alternative DDT_site_2); the DDT tutorial movie is available here.
Supplementary information
Supplementary data are available at Bioinformatics online
The cut runs deep: Linking the cut marks to the cutting tools
The analysis of bone surface modifications (BSM), such as butchering marks, is necessary to better understand how the exploitation of animal resources by past hominins influenced their biological and cultural evolution. Even if several studies have been carried out on this topic in the last decades, there are still some phenomena which need to be thoroughly understood. Here we try to quantify how can the depth of cut marks influence the shape of their cross-sections. This is of crucial important for a valid interpretation of shape data collected on archaeological BSMs. In particular, two groups of cut marks’ cross-sections experimentally produced with two flint burins on a cattle innominate are analysed in this paper by means of 3D microscopy and geometric morphometrics. The two sets of striae show a different depth and a different cross-sectional shape. In particular, shallower cross sections are characterized by less steep walls and consequently by a wider opening angle. If analysis moves to the characteristics of the cutting edge of the burins, it comes out that the different shape between the two groups of striations is probably a function of the way in which the tool penetrates into the bone. These results are relevant for taphonomy, since similar difference in cross-sectional shape were found between marks produced with different raw materials. This contribution highlights the importance of considering the characteristics of tool’s cutting edges in evaluating the meaning of shape variability of cut marks cross-sections. © 2019 International Conference on Metrology for Archaeology and Cultural Heritage
Valle Giumentina (Abruzzes, Italie)
Les objectifs de la mission de terrain 2016 Valle Giumentina est un gisement des Abruzzes du Paléolithique ancien et moyen en plein air, connu grâce aux travaux approfondis des années 1950 menés par le préhistorien A. M. Radmilli et le géologue J. Demangeot. Sept horizons archéologiques avaient été mis au jour en contexte globalement lacustre, à la faveur d’une ravine profonde qui a incisé les dépôts du Pléistocène jusqu’à 25 m de profondeur. Les recherches pluridisciplinaires entreprises dan..
I sistemi informativi automatizzati a supporto dei processi di direzione aziendale. Ancora un ritardo cronico per le piccole imprese?
Il lavoro esamina i sistemi informativi automatizzati funzionali al supporto delle attività di pianificazione e controllo, allo scopo di verificare se aziende di dimensione diversa registrano tassi di adozione differenti. Inoltre, particolare attenzione viene dedicata alla percezione dei potenziali benefici derivanti dall’adozione di tali sistemi. I risultati confermano la tendenza delle piccole imprese ad utilizzare i sistemi informativi automatizzati soprattutto a livello operativo e poco a sostegno della formulazione delle strategie
Valle Giumentina (Abruzzes, Italie)
Les objectifs de la mission de terrain 2014 Valle Giumentina est un gisement des Abruzzes du Paléolithique ancien et moyen en plein air, fouillé brièvement dans les années 1950 par le professeur A. M. Radmilli de l’Université de Pise, en collaboration avec le géologue J. Demangeot. Sept horizons archéologiques ont été mis au jour en contexte globalement lacustre, à la faveur d’une ravine profonde qui a incisé les dépôts du pléistocène jusqu’à 25 m de profondeur. Dans le cadre du programme qui..
Using 3D Microscopy to Analyze Experimental Cut Marks on Animal Bones Produced with Different Stone Tools
This study uses a combination of digital microscopic analysis and experimental archaeology to assess stone tool cut marks on animal bones. We used two un-retouched flint flakes and two burins to inflict cut marks on fresh, boiled, and dry ungulate bones. The experiment produced three series of three engravings on each bone with each of the experimental tools. The first series involved one single stroke; the second, two strokes in the same direction; and the third, multiple strokes using a to-and-fro movement. We analyzed the striations using a Hirox 3D digital microscope (KH-7700) and collected metric and profile data on the morphology of the cut marks. In order to describe the shape of each cross section, we calculated the ratio between the breadth at the top and the breadth at the floor of cut marks. Preliminary results show that both the tool type and the method of creating the cut mark influence the shape of the resulting groove. In our experiment, morphological parameters can be used to differentiate between marks produced using un-retouched flint flakes and those produced using burins. However, neither morphological nor morphometric analysis allows us to identify the mechanical motion used to produce the cuts, nor the state of the bone (fresh, boiled, or dry) at the moment of marking
Enhanced Methodology to Characterize 3-D Power Monitoring and Control Features for 5G NR Systems Embedding Multi-User MIMO Antennas
A Theoretical and Experimental Investigation on the Measurement of the Electromagnetic Field Level Radiated by 5G Base Stations
A Methodology to Characterize Power Control Systems for Limiting Exposure to Electromagnetic Fields Generated by Massive MIMO Antennas
The fifth-generation (5G) New Radio (NR) cellular network has been launched recently. The assignment of new spectrum bands and the widespread use of Massive MIMO (MaMIMO) and beamforming techniques for better radio coverage are two major features of the new architecture. They imply both opportunities and challenges, one of the most daring one among the latter ones is the research for methods to assess human exposure to electromagnetic fields radiated by the base stations. The long-term time-varying behavior and spatial multiplexing feature of the MaMIMO antennas, along with the radio resource utilization and adoption of Time-Division Duplexing (TDD), requires that the assessment of exposure to electromagnetic fields radiated by 5G systems is based on a statistical approach that relies on the space and time distribution of the radiated power. That, in turn, is determined through simulations based on the actual maximum transmitted power - defined as the 95 th percentile of the empirical distribution obtained from historical data of radiated power - rather than on the nominal one. To ensure that exposure limits are never exceeded, a monitoring and control system (usually referred to as Power Lock (PL)) that limits the transmitted power can be used. In this paper we propose a methodology, independent from the specific technical solution implemented by the manufacturer, to characterize such control systems and determine their capability to limit the average power transmitted over a given time interval to a value that keeps the corresponding average exposure to electromagnetic fields below a specified value. Experimental results show the effectiveness of the methodology and that it can also be used to identify when the PL interacts with the higher levels of the MaMIMO system architecture
Middle Palaeolithic technical behaviour: Material import-export and Levallois production at the SU 13 of Oscurusciuto rock shelter, Southern Italy
The Oscurusciuto rock shelter, located in southern Italy (Puglia), has yielded a long Middle Palaeolithic stratigraphy rich in lithic assemblages, fireplaces and faunal remains, attesting Neanderthal occupation during the MIS 3. This paper is focused on the stratigraphic unit 13, consisting of a sandy compact deposit mixed with pyroclastic sediment above a thick level of tephra-US 14, identified as Mt. Epomeo green tuff (dated Ar/Ar ~ 55 ka).Level 13 represents the first stable human occupation after the deposition of tephra. Our goal was to examine the lithic assemblage of this stratigraphic unit by means of an interdisciplinary approach (technology, RMU, refitting program) in order to identify the economic behaviour and technical strategies of Neanderthals occupying the stratigraphic unit 13 of Oscurusciuto.The technical strategies applied indicate fragmentation of the reduction processes, as well as probable events of importation and exportation of objects. The lithic material were introduced at different stages of manufacturing. Pieces were introduced in the form of rough objects (pebbles), as well as semi-finished items, and as finished tools. This fragmentation of the chaîne opératoire also demonstrate the palimpsest nature of the level which is made up of different events happening one after another.The main concept of debitage was Levallois, generally realized on local jasper and siliceous limestone pebbles or cortical flakes. Jasper and siliceous limestone flakes, backed flakes and convergent flakes were the technological objectives of the debitage. A marginal volumetric debitage aimed at producing bladelets was also attested.
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