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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>PrEVIEw: Clustering and Visualising PubMed using Visual Interface</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Syeda Sana e Zainab</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Qaiser Mehmood</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Durre Zehra</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Dietrich Rebholz-Schuhmann</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ali Hasnain</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Insight Centre for Data Analytics, National University of Ireland</institution>
          ,
          <addr-line>Galway</addr-line>
        </aff>
      </contrib-group>
      <fpage>17</fpage>
      <lpage>27</lpage>
      <abstract>
        <p>The life sciences domain has been one of the early adopters of Open Data Initiative and a considerable portion of the Linked Open Data cloud is comprised of datasets from Life Sciences Linked Open Data (LSLOD). This deluge of biomedical data and active research over the past decade resulted in the flux of scientific publications in this domain. PubMed resource provides access to MEDLINE, NLM's database of citations and abstracts in the biomedical domain. PubMed Central provides links to full-text articles along with publisher web sites, and other related resources. In this paper we present PubMed Visual Interface (PrEVIEw)a web based application to access information related to publication, research topic, author and institute through a visual interface. PrEVIEw not only provides useful information e.g. research topic of interest, research collaboration at personal or institute level etc, for the biomedical research community but also helpful for the working Data Scientist. We also evaluate the usability of our system by using the standard system usability scale as well as a custom questionnaire, particularly designed to test the usability of the interface. Our overall usability score of 83.69 suggests that web based interface is easy to learn, consistent, and adequate for frequent use.</p>
      </abstract>
      <kwd-group>
        <kwd>PubMed</kwd>
        <kwd>Publication</kwd>
        <kwd>Visual Interface</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        The deluge of biomedical data in the last few years, partially caused by the
advent of high-throughput gene sequencing technologies [
        <xref ref-type="bibr" rid="ref2 ref3 ref5">3,5,2</xref>
        ], has been a
primary motivation for efforts in this area. The significant contributors includes
the Bio2RDF project1, Linked Life Data2, Neurocommons3, Health care and
Life Sciences knowledge base4 (HCLS Kb) and the W3C HCLSIG Linking Open
Drug Data (LODD) effort5. These efforts have been partially derived and are
still motivated by the deluge of data in biomedical facilities in the past few years,
partially caused by the decrease in price for acquiring large datasets such as
genomic sequences (e.g. the cost of sequencing the genome has dropped faster than
Moore’s law) and the trend towards personalised medicine, pharmacogenomics
and integrative bioinformatics. This increase in biomedical research has resulted
in the drastic increase in scientific publications in this area. This includes both
Conference as well as Journal publications. In order to investigate the ongoing
research trends, similar or related research contribution and possible research
collaboration one has to keep an eye on the research papers from peer scientist.
There is a need for an integrated system where one can find the answers for
the questions e.g. List of all the authors who publish their research on Lungs
Cancer in any conference. With the emergence of PubMed it become possible to
access the MEDLINE, NLM’s database of citations and abstracts in the
biomedical domain including medicine, nursing, veterinary medicine, dentistry, health
care systems, and preclinical sciences. PubMed Central provides links to
fulltext articles along with publisher web sites, and other related resources. Using
PubMed, one has to access their web interface in order to search for any
publication or through RESTful Web Services. Using these RESTful services poses
limitations for Biomedical researchers searching for relevant articles as they are
domain user with limited or no knowledge of using such services[
        <xref ref-type="bibr" rid="ref15 ref4">15,4</xref>
        ]. In this
paper we introduce PrEVIEw a web based application that uses RESTful Web
Services provided by PubMed and user can search for any topic e.g. Cancer,
and all the relevant information regarding the publications about the searched
concepts along with the publication type, author and institutes involved in the
Cancer research are retrieved through graphical and intuitive interface. This
interface make it easier to cluster Authors working on similar topics or institutes
involved in any particular research area.
      </p>
      <p>The remaining part of this paper is organised as follows: we highlight the
related work in section 2. We introduce our methodology and PrEVIEw salient
features in section 3. Later we present the usage scenario in section 4.
Subsequently, we present an evaluation of our approach in section 5. We finally
conclude the paper.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related Work</title>
      <p>
        AMiner by Tang J et. al creates semantic-based profile for each researcher in ored
to built researcher social network.[
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] Osborne F Et. al introduce tool Rexplore
which mainly focus on relating authors semantically in order to understand the
dynamics of research area. [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] Monaghan F et. al introduce application Saffron
which extract information from unstructured documents using Natural Language
Processing techniques.[
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] Wu et. al [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] visualised author collaboration network
for schizophrenia disease, between year 2003 to 2012 using CiteSpace III
visualisation. Xuan et. al [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ], developed Medline exploration approach for interactive
visualisation. They made use of PubViz, for grouping, summary, sorting and
active external content retrieval functions. Similarly Joseph T et. al, introduced
      </p>
      <p>
        TPX [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] which is a web-based PubMed search enhancement tool that enables
faster article searching using analysis and exploration features in tabular form. In
the book “Analysis and Visualisation of Citation Networks” Zhao et. al [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ],
discussed mapping research fields through citation analysis. H Chen et. al presented
NLP-based text-mining approach, “Chilibot”, [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] which constructs content-rich
relationship graph networks among biological concepts, genes, proteins, or drugs
from pubmed (abstract). Table 1 shows a brief comparison of PrEVIEw with
similar systems.
      </p>
      <p>
        The table 1 shows that PrEVIEw is not limited for searching particular topic,
not confined for searching articles for specific time frame, or specific database of
pubmed neither for the social networking purposes. Furthermore tabular display,
can be difficult to pull off linked information while concept map approach [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]
used by PrEVIEw show better interactions. PrEVIEw can also retrieved results
based on most recent publications instead of most cited ones [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. PrEVIEw
also supports searching and navigation through visualisation that makes it more
intuitive to use.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Methodology</title>
      <p>Our methodology consists of two steps namely: 1) result retrieval using Rest
API’s and 2) building visual interface .</p>
      <p>
        Result Retrieval Using Rest API’s REST (Representational State Transfer)
is a communication approach that is often used in the development of Web
services6 and involves reading any Web page that contains an XML file. PrEVIEw
6 http://searchsoa.techtarget.com/definition/REST
make use of REST APIs7 provided by PubMed and overall result retrieval works
as follow: (1) User search a topic, institute, title of the publication or author and
send the request, (2) Rest API’s fetch data in the form of XML, (3) XML parser
with data manipulator creates JSON file and transfer to presentation layer.
Building Visual Interface The analysis of large numbers of biomedical
publications, in the form of graphical representation made it possible for researchers
to extract the relevant publications for future collaboration. We chose the
concept map approach [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] for building the visual interface, which is a graphical
method representing the relationship between nodes and links, and has been
used in various domains for organising knowledge. Using this approach we
represent concepts of title, topic, authors and institutes and relevant publications.
Greater the occurrence of any searched concept bigger the size of the circular
node representing that concept. Due to large amount of data we only present top
100 cited occurrence for any searched concept. Subsequent results are displayed
in a tabular form using ”View All Records” option. Interface also provides the
graphical representation of topic, authors or institute and respective occurrence
(the number of times it occur in the result).
      </p>
      <p>Technologies PrEVIEw is browser-based client application that provides a
flexible front-end for searching. To build this application variety of web
technologies are used including HTML5, CSS, JavaScript, JQuery8, Rest API’s 9,
Java Servlet, SVG10, AJAX11 and JSON12.</p>
      <p>Availability The PrEVIEw application can be accessed at http://srvgal78.
deri.ie/PrEVIEw/.
3.1</p>
      <sec id="sec-3-1">
        <title>System Overview</title>
        <p>
          Fig. 1: PrEVIEw Architecture: Data, Business and Presentation layer.
all the relevant publications is retrieved at the Data Layer and corresponding
JSON is generated at the Business Layer. At the Presentation Layer,
graphical and visual representation of PId’s (PubMed Id’s), authors and institute are
displayed as clusters. Complete metadata description of publications can be
accessible by clicking on PId’s . For the second challenge, the classification, we
adopt the technique that relies on publication mapping, a web-based client
application PrEVIEw is developed. Publications are mapped in the form of clusters
classifying author, topic, title and institute separately. Authors and institutes
with remarkable contribution in regard to particular topic search, represented as
larger node. Additionally, the publications can be downloaded. We applied two
mapping techniques to this application: force directed placement [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ] for clusters
and chart summary for highly ranked search results.
4
        </p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Usage Scenarios</title>
      <p>Recognising the value of research networking, two example scenarios are
discussed to demonstrate the use of PrEVIEw. First use-case visualises PubMed
ID’s and authors as the outcome from topic/title query. For second use-case,
the institutional outcomes have been used. The combination of these two
usecase enables establishing research networks and collaborations at authors and
institution level. Details of these two outcomes have been discussed below.
Highly cited publications with the author list having paper on
”cancer” research The step-by-step approach is discussed as follow (Fig. 2):
1. The first step is to specify the selection of the corresponding text. User search
”cancer” while selecting Topic from the drop-down menu. (window A).
2. The visualisation of top 100 highly cited papers on cancer can be seen in
(window B) where user can explore them using PubMed Id’s and and
description about the full paper can be explored (window D).
3. List of all authors (from top 100 cited papers) working on cancer domain
is shown in (window C) where a mouse-hover further display the ”author’s
name”.
4. Selected author contribution in cancer research (window E) provide user the
ability to download all the relevant papers in cancer domain.</p>
      <p>Authors collaborations at international level increase citations of research manuscripts.
One of the novel advancement in the mode represented in Figure 2 is establishing
authors research networks and collaborations on a focused domain.</p>
      <p>Research Institutes working on ”cancer research”, and their
collaborations with other institutes The step-by-step approach is discussed as
follows(Fig. 3):
1. The first step is to specify the selection with the corresponding text. In this
case ”cancer” while selecting ”Topic” from ”drop-down menu” (window A).
2. The visualisation of highly cited cancer papers can be seen (window B) where
user can explore them using PubMed Id’s.
3. List of all institutes working on ”cancer research” are shown in (window C)
where user is able to explore any of them by selection.
4. Selected institute collaboration with other institutes in cancer research is
shown in publication metadata, (window D).</p>
      <p>The exponential growth in international collaboration on focused scientific
research questions shows the novelty in the mode represented in Figure 3.
Institutional collaboration enables shared learning, new research opportunities,
establishing new research projects, joint applications for funds, and technology
transfer. Findings from these different kinds of networks can be used in many
ways. Collaboration networks in terms of highly cited authors , institutions, and
countries are highlighted in the publication set. Semantic networks can identify
various research directions the focused concepts. Further more publication
citation networks can be used to quantify the citation impact in research directions
and disciplines.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Evaluation</title>
      <p>
        The goal of our evaluation is to quantify the usability and usefulness of
PrEVIEw graphical interface. We evaluate the usability of the interface by using the
standard System Usability Scale (SUS) [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] as well as a customised questionnaire
designed for the users of our system. In the following, we explain the survey
outcomes.
5.1
      </p>
      <sec id="sec-5-1">
        <title>System Usability Scale Survey</title>
        <p>
          In this section, we explain the SUS questionnaire13 results. This survey is more
general and applicable to any system to measure the usability. The SUS is a
simple, low-cost, reliable 10 item scale that can be used for global assessments
of systems usability[
          <xref ref-type="bibr" rid="ref9">9</xref>
          ].
        </p>
        <p>As of 3rd May 2016, 22 users14 including researchers and engineers in
Semantic Web participated in survey. According to SUS, we achieved a mean usability
score of 83.69 indicating a high level of usability according to the SUS score. The
average scores (out of 5) for each survey question along with standard deviation
is shown in Figure 4.</p>
        <p>The responses to question 1 (average score to question 4.2 = ± 0.72) suggests
that PrEVIEw is adequate for frequent use. The responses to question 3 indicates
that PrEVIEw is easy to use (average score 4.5 ± 0.51) and the responses to
question 7 (average score 4.4 ± 0.59) suggests that most people would learn to
use this system very quickly. However, the slightly higher standard deviation to
question 9 (standard deviation = ± 0.74) and question 10 (standard deviation
13 SUS survey can found at: https://goo.gl/hkuMDM
14 Users from AKSW, University of Leipzig and INSIGHT Centre, National University
of Ireland, Galway. Summary of the responses can be found at: https://goo.gl/
iKaZjQ
= ± 0.39) suggest that we may need a user manual to explain the different
functionalists provided by the PrEVIEw interface.
This survey15 was particularly designed to measure the usability and usefulness
of the different functionalists provided by PrEVIEw. In particular, we asked
users to use our system and share their experience through question 9 and
question 10. As of 3rd May 2016, 13 researchers including Computer Scientist16 and
Bioinformaticians have participated in survey. The average scores (out of 5 with
1 meaning strongly disagree and 5 meaning strongly agree) for each survey
question along with standard deviation is shown in Figure 5. The average scores to
question 10 (i.e., 4.45 ± 0.73), show that most of the users feel confidence to use
the system and need not to learn much about the PrEVIEw before using. The
responses to question 2 (average score = 4.07 ± 0.64) suggest that exploring
highly cited publications using PubId selection is easy in PrEVIEw. A slightly
lower scores to question 7 (average score = 4.38 ± 0.51) suggests that we need
to further improve the user experience with visualisation components of the
PrEVIEw.
15 Custom survey can be found at: https://goo.gl/syZzAM
16 Summary of the responses can be found at: https://goo.gl/JKogDQ
6</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>Conclusion and Future Work</title>
      <p>In this paper we introduce PrEVIEw as an online visual and graphical interface
for searching PubMed resource. We evaluate our approach and usability of our
system using the standard system usability scale as well as through domain
experts. Our preliminary analysis and evaluation revels the overall usability score
of 83.69, concluding PrEVIEw an interface, easy to learn and help users accessing
PubMed resource intuitively. As a future work we aim to extend PrEVIEw with
Faceted browsing and also provide visualisation at entity level e.g, Genes and
Molecules where the search criteria retrieve these entities. Current work visualise
top 100 cited results and in future we aim to visualise all retrieved results.</p>
    </sec>
    <sec id="sec-7">
      <title>Acknowledgement References</title>
      <p>This research has been supported in part by Science Foundation Ireland under
Grant Number SFI/12/RC/2289.</p>
    </sec>
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