LifeWatchGreece: Construction and operation of the National Research Infrastructure (ESFRI)

Editorial article explaining the background to and introducing a collection of papers describing the construction and operation phase of the Greek LifeWatch distributed centre: LifeWatchGreece

A Reference Architecture for Virtual Research Environments

This paper describes the Reference Architecture of the enhanced VRE (e-VRE), a Virtual Research Environment defined in the context of the VRE4EIC Project, funded by EU H2020 e-Infrastructure program. e-VRE is designed to overcome limits of existing VREs with respect to a number of orthogonal dimensions: improving the quality of VRE user experience by providing user centered, secure, privacy compliant, sustainable environments for accessing data, composing workflows and tracking data publications; increasing VRE usage in multidisciplinary research domains by abstracting and reusing building blocks and workflows from existing VRE initiatives; improving the interoperability of heterogeneous discovery, contextual and detailed metadata across all layers of the VRE

Quantifying the Connectivity of a Semantic Warehouse

In many applications one has to fetch and assemble pieces of information coming from more than one SPARQL endpoints. In this paper we describe the corresponding requirements and challenges, and then we present a process for constructing such a semantic warehouse. We focus on the aspects of quality and value of the warehouse, and for this reason we introduce various metrics for quantifying its connectivity, and consequently its ability to answer complex queries. We demonstrate the behavior of these metrics in the context of a real and operational semantic warehouse. The results are very promising: the proposed metrics-based matrixes allow someone to get an overview of the contribution (to the warehouse) of each source and to quantify the benefit of the entire warehouse. The later is useful also for monitoring the quality of the warehouse after each reconstruction. 1

Electricity supply on the island of Dia based on renewable energy sources (R.E.S.)

This paper presents a methodology for determining the specifications of an isolated R.E.S. power production system on an environmentally sensitive ecosystem. The wind and solar power constitute the primary power generation system and diesel generators act as backup. Real wind and solar potential measurements are used. The wind atlas of the island has been constructed. The specifications of the proposed system are optimized by the life cycle cost method. The renewable energy sources (R.E.S.) total annual energy production exceeds 90%. As a result, the dependence on the diesel generator set annual energy production is limited and the system's operational cost is not practically influenced by the increasing fossil fuel prices. The introduction of a small size desalination plant for the production of drinkable water is also investigated. Both the available R.E.S. potential and the minimization of environmental impacts are considered for the siting of the equipment. The methodology of the present paper may be applied to other regions rich in R.E.S. potential, where the introduction of small size environmentally friendly isolated R.E.S. power systems is investigated.Wind Photovoltaic Renewable Energy Power Hybrid

X3ML mapping framework for information integration in cultural heritage and beyond

The aggregation of heterogeneous data from different institutions in cultural heritage and e-science has the potential to create rich data resources useful for a range of different purposes, from research to education and public interests. In this paper, we present the X3ML framework, a framework for information integration that handles effectively and efficiently the steps involved in schema mapping, uniform resource identifier (URI) definition and generation, data transformation, provision and aggregation. The framework is based on the X3ML mapping definition language for describing both schema mappings and URI generation policies and has a lot of advantages when compared with other relevant frameworks. We describe the architecture of the framework as well as details on the various available components. Usability aspects are discussed and performance metrics are demonstrated. The high impact of our work is verified via the increasing number of international projects that adopt and use this framework

LifeWatch Greece data-services: Discovering Biodiversity Data using Semantic Web Technologies

Biodiversity data is characterized by its cross-disciplinary character, the extremely broad range of data types and structures, and the variety of semantic concepts that it encompasses. Furthermore there is a plethora of different data sources providing resources for the same piece of information in a heterogeneous way. Even if we restrict our attention to Greek biodiversity domain, it is easy to see that biodiversity data remains unconnected and widely distributed among different sources. To cope with these issues, in the context of the LifeWatch Greece project, i) we supported cataloguing and publishing of all the relevant metadata information of the Greek biodiversity domain, ii) we integrated data from heterogeneous sources by supporting the definitions of appropriate models, iii) we provided means for efficiently discovering biodiversity data of interest and iv) we enabled the answering of complex queries that could not be answered from the individual sources. This work has been exploited, evaluated and scientificaly confirmed by the biodiversity community through the services provided by the LifeWatch Greece portal

Micro-CTvlab: A web based virtual gallery of biological specimens using X-ray microtomography (micro-CT)

During recent years, X-ray microtomography (micro-CT) has seen an increasing use in biological research areas, such as functional morphology, taxonomy, evolutionary biology and developmental research. Micro-CT is a technology which uses X-rays to create sub-micron resolution images of external and internal features of specimens. These images can then be rendered in a three-dimensional space and used for qualitative and quantitative 3D analyses. However, the online exploration and dissemination of micro-CT datasets are rarely made available to the public due to their large size and a lack of dedicated online platforms for the interactive manipulation of 3D data. Here, the development of a virtual micro-CT laboratory (Micro-CTvlab) is described, which can be used by everyone who is interested in digitisation methods and biological collections and aims at making the micro-CT data exploration of natural history specimens freely available over the internet. The Micro-CTvlab offers to the user virtual image galleries of various taxa which can be displayed and downloaded through a web application. With a few clicks, accurate, detailed and three-dimensional models of species can be studied and virtually dissected without destroying the actual specimen. The data and functions of the Micro-CTvlab can be accessed either on a normal computer or through a dedicated version for mobile devices

Tungsten Disulfide-Interfacing Nickel-Porphyrin For Photo-Enhanced Electrocatalytic Water Oxidation

11 figures, 2 tables.-- Supporting information available.Covalent functionalization of tungsten disulfide (WS2) with photo- and electro-active nickel-porphyrin (NiP) is reported. Exfoliated WS2 interfacing NiP moieties with 1,2-dithiolane linkages is assayed in the oxygen evolution reaction under both dark and illuminated conditions. The hybrid material presented, WS2−NiP, is fully characterized with complementary spectroscopic, microscopic, and thermal techniques. Standard yet advanced electrochemical techniques, such as linear sweep voltammetry, electrochemical impedance spectroscopy, and calculation of the electrochemically active surface area, are used to delineate the catalytic profile of WS2−NiP. In-depth study of thin films with transient photocurrent and photovoltage response assays uncovers photo-enhanced electrocatalytic behavior. The observed photo-enhanced electrocatalytic activity of WS2−NiP is attributed to the presence of Ni centers coordinated and stabilized by the N4 motifs of tetrapyrrole rings at the tethered porphyrin derivative chains, which work as photoreceptors. This pioneering work opens wide routes for water oxidation, further contributing to the development of non-noble metal electrocatalysts.Financial support by the Hellenic Foundation for Research and Innovation HFRI under the “2nd Call for HFRI Research Projects to support Faculty Members and Researchers” (Project Number: 2482) to N.T. is acknowledged. [...] R.A. acknowledges support from Spanish MCIN (PID2019-104739GB-I00/AEI/10.13039/501100011033), Government of Aragon (projects DGA E13-20R) and from EU H2020 “ESTEEM3” (Grant number 823717) and Graphene Flagship (881603). W.K.M and A.M.B acknowledge support from Spanish MCIN (PID2019-104272RB-C51/AEI/10.13039/501100011033), and the Government of Aragon (Grupos Reconocidos DGA T03_20R).Peer reviewe

Towards a Global Record of Stocks and Fisheries

The collation of information for the monitoring of fish stocks and fisheries is a difficult and time-consuming task, as the information is scattered across different databases and is modelled using different formats and semantics. Our purpose is to offer a unified view of the existing stocks and fisheries information harvested from three different database sources (FIRMS, RAM and FishSource), by relying on innovative data integration and manipulation facilities. In this paper, we describe the activities carried out to realize the Global Record of Stocks and Fisheries (GRSF) which aims at offering an integrated and enriched view on data about fish stocks and fisheries from the database sources. More specifically we describe the model, the workflow and the software components for producing GRSF records and make them easily available to the users