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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Towards Realization of Scientific Dataspaces for the Breath Gas Analysis Research Community</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Ibrahim Elsayed</string-name>
          <email>elsayed@par.univie.ac.at</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Thomas Ludescher</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Konrad Schwarz</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Thomas Feilhauer</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Anton Amann</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Peter Brezany</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Associate Editors: Sandra Gesing</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jano van Hemert</string-name>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Operative Medicine, Innsbruck Medical University</institution>
          ,
          <addr-line>Innsbruck</addr-line>
          ,
          <country>Austria and</country>
          <institution>Breath Research Institute of the Austrian Academy of Sciences</institution>
          ,
          <addr-line>Innsbruck</addr-line>
          ,
          <country country="AT">Austria</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Department of Scientific Computing, Faculty of Computer Science, University of Vienna</institution>
          ,
          <addr-line>Nordbergstrasse 15/C/3, 1090 Vienna</addr-line>
          ,
          <country country="AT">Austria</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Research Center for Process and Product Engineering, Vorarlberg University of Applied Sciences</institution>
          ,
          <addr-line>Hochschulstrasse 1, 6850 Dornbirn</addr-line>
          ,
          <country country="AT">Austria</country>
        </aff>
      </contrib-group>
      <fpage>1</fpage>
      <lpage>8</lpage>
      <abstract>
        <p>Motivation: Scientific dataspaces aim at providing associated mechanisms for managing semantically rich relationships among scientific data sources (primary data) and its corresponding findings (derived data). The latter result from a set of activities defining concrete preprocessing and analysis methods (background data) that were applied to a source dataset. To keep track of scientific experiments that are being conducted by members of a scientific community these experiments should be linked with user information i.e. institutional affiliation, email address, working field, etc. of the scientist who conducted the experiment. This paper deals with the development of a scientific dataspace for the breath gas analysis community. Breath gas analysis is an emerging new scientific field with a growing international scientific community addressing many different breath gas studies in terms of investigating and screening for hundreds of compounds in exhaled breath gas. The purpose of breath gas analysis scientific dataspaces is to enable collaborating scientists and institutions several important activities, which include: (a) access to distributed breath gas data and analytical resources collected and developed at different research institutions around the world and (b) to easily contribute to and leverage the resources of an international- and national-scale, multi-institutional environment. Results: This paper describes the conception and prototypical implementation of the scientific dataspace paradigm for breath gas analysis. The scientific dataspace is evaluated on top of applications from breath gas analysis. Availability: We discuss the scientific dataspace paradigm in the context of applications from breath gas analysis, however the concepts introduced can also be deployed in other research domains. Contact: elsayed@par.univie.ac.at</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1 INTRODUCTION</title>
      <p>The project Austrian Grid 2 is the second phase of the national
grid initiative funded by the Austrian Federal Ministry of Science
and Research1. The Austrian Grid consortium combines Austria’s
leading researchers in advanced computing technologies with
well-recognized partners in grid-dependant application areas. An
overview of the Austrian Grid project is provided in 4. In 2007, three
partners of the Austrian Grid consortium have started a research
collaboration with the intention to realize a Secure Infrastructure
for Scientific Data Life Cycle Management on top of applications in
the field of breath gas analysis. This project is described in 6. That
paper presents motivation, an overview of the architecture, and the
mechanisms involved in providing such a secure infrastructure. It
also introduces use case scenarios depicting the current sequence
of events in conducting breath gas analysis experiments. Our
data management approach is based on the Grid and dataspace
concepts and a new positioning of the MATLAB R language and
computing environment. The Grid is an infrastructure that enables
flexible, secure, and coordinated resource sharing among dynamic
collections of individuals and institutions 11. The idea of a future
data management paradigm called dataspace was introduced by
Franklin et al. 12 and also addressed by authors of this paper in
8, 9. The goal is to manage a dataspace, rather than a database or
other dataset type. Dataspaces are modeled as participants (datasets)
and relationships. The concepts of a scientific dataspace paradigm
are described in 9. It introduces a specific model of the e-Science
life cycle, which the authors defined as:
... a domain independent ontology-based iterative metamodel,
tracing semantics about procedures in e-Science applications.
Iterations of the model - so called e-Science life cycles
organized as instances of the e-Science life cycle ontology,
are feeding a dataspace, allowing the dataspace to evolve and
grow into a valuable, intelligent, and semantically rich space
of scientific data.</p>
      <p>The major role of the e-Science life cycle ontology 15 is
to describe and semantically enrich the existing relationship
among primary, background and derived datasets in e-Science
1 BMWF (Federal Ministry of Science and Research) Contract: GZ
BMWF10.220/0002-II/10/2007 www.austriangrid.at
applications. Scientific experiments described by the e-Science life
cycle ontology are referred to as Life Cycle Resources (LCR).
This paper deals with an implementation of a scientific dataspace
paradigm on top of the e-Science life cycle ontology for the breath
gas analysis research community.</p>
      <p>Breath gas analysis is an emerging new scientific field with
a large scientific community spread all over the world and with
a promising significant impact on many application domains.
Recent results suggest that detection of different kinds of cancer
is possible by means of breath gas analysis beyond the scope of
available diagnostic methods. There is strong evidence that specific
cancers can be detected using the concentration pattern of volatile
compounds in exhaled air 17.</p>
      <p>The growing international community of breath gas researchers
is addressing many different studies including
endogenouslyderived volatile compounds such as emitted by exhaled breath,
from skin, urine, faeces, and flatulence. They are currently
at the stage of developing new analytical methods, collecting
pilot data for cancer and other diseases and identifying marker
compounds. Breath gas researchers are investigating and screening
for hundreds of compounds in the exhaled breath gas. The
analytical instruments and techniques used include GC-MS (Gas
Chromatography Mass Spectrometric), PTR-MS
(Proton-TransferReaction Mass Spectrometry), SIFT-MS (Selected-Ion-Flow-Tube
Mass Spectrometry), IMS (Ion Mobility Spectrometry), laser
spectrometry - as well as various statistical and data mining
techniques supporting identification of specific markers. Currently,
during the investigations new different sampling and analytical
techniques for breath gas measurements are being developed. More
information about the breath gas research community and their
research work is available in 3 and online at the website of the
International Association for Breath Research (IABR - www.iabr.li),
which was founded in May 2005 in Vienna.</p>
      <p>The purpose of breath gas analysis scientific dataspaces is to
enable collaborating scientists and institutions several important
activities, which include: (a) access to distributed breath gas
data and analytical resources collected and developed at different
research institutions around the world, (b) to easily contribute
to and leverage the resources of an international- and
nationalscale, multi-institutional environment. This will strongly support
global collaborations of scientists, improve decisions and increase
the chance and scope of discoveries in the breath gas research
domain. In this context there is a need for a supporting information
infrastructure providing advanced data management and analytical
methods and their composition into scientific experiments allowing
the scientist to keep track of their e-Science activities and to publish
corresponding results of breath gas analysis linked together with
their source data and semantics about the purpose of the experiment.</p>
      <p>Source data obtained from the previously mentioned analytical
methods are referred to as breath gas measurement data and are
saved, together with corresponding patient data, locally at each
research center. These data are the fundament for simulation and
modeling by the acting research group, e.g. observation of the
correlation between isoprene breath content and cholesterol level
in blood. Such breath gas experiments, if evaluated on large amount
of real data, allow a more detailed analysis including e.g.
genderspecific relation with respect to age-dependency 14. The output of
these analyses aims at defining a large number of predictions and
might provoke further experimentation, which in turn may take
days or weeks, depending on computational and human resources
available. However, the resulting derived data, that have arisen
from the research task represent valuable information not only to
the acting research group, but also to other groups with respect to
other main focuses.</p>
      <p>Breath gas research specific dataspaces will be set up to serve
a special subject, which is on one hand the relationship of source
data (exhaled breath gas measurement data) and its derived data
(e.g. specific cancer markers) in breath gas analysis experiments
and on the other hand to integrate scientific knowledge into these
experiments.</p>
      <p>This paper discusses the design of a scientific dataspace paradigm
for the breath gas analysis scientific community. The rest of this
document is set out as follows: Section 2 introduces selected use
case scenarios, lists the currently known uses of the scientific
dataspace and describes the information a breath gas analysis
scientific dataspace should contain and how this information is
organized; Section 3 describes the operations the dataspace must
support with an indication of how breath gas researcher will interact
and take advantage of the services the scientific dataspace provides.
In Section 4 we discuss the iterative approach of conducting breath
gas experiments on top of the e-Science life cycle model and in
Section 5 we conclude the paper.
2</p>
    </sec>
    <sec id="sec-2">
      <title>APPROACH</title>
      <p>In our previous work we have introduced the e-Science life cycle
ontology 9, whose major goal was to semantically enrich the
existing relationship among primary, derived, and background
datasets that emerge during the life cycle of scientific data. The
goal is to implement a data management solution based on the
concepts of dataspaces for large-scale and long-term management of
scientific data. Our approach is to preserve both, relationships and
data together within a dataspace to be reused by owners and others.
To enable their reuse, data must be well preserved. The effects of
data loss can be economic, because the experiments have to be
re-run, but in some cases data loss represents an opportunity lost
forever 18. To look on the bright side of things, well preserved data
represent valuable information, which can lead to fruitful scientific
findings in the acting and also in related research areas. Preservation
of scientific data is therefore a major requirement, which can best
be established if the full life cycle of data is addressed. This is
achieved in our approach by the e-Science life cycle ontology. In the
following sections we describe how breath gas analysis experiments
are consolidated, what actions are involved in terms of data access,
analysis, and publication. We also show how the full life cycle
of data of breath gas experiments is organized by the breath gas
analysis scientific dataspace.
2.1</p>
      <sec id="sec-2-1">
        <title>Breath Gas Analysis Dataspace Usage</title>
        <p>The use case scenario depicting the current sequence of events in
conducting breath gas analysis experiments is illustrated in Fig. 1,
which is reproduced from the position paper 6. It presents an
overview, with the Server being an isle system gathering the data.
Import and export activities on this system are protected by smart
card security measures.</p>
        <p>The implementation of a secure infrastructure, which provides the
needed services for breath gas researchers to efficiently and securely
perform steps 1 to 7 is part of the project described in 6. However,
the present document focuses on the realization of a scientific
dataspace for the breath gas scientific community. We assume
that a secure and isolated database storing masspectrometer and
patient data is already set up and administered by the corresponding
Regional Head Service as described in 6. In the following we refer
to this database as the source database.</p>
        <p>We are aware that in order to successfully establish a
largescale scientific dataspace for the breath gas analysis community
with a large amount of well described experiments of exhaled
breath, we rely on active participation of members of the scientific
community. Therefore we have - in cooperation with leading breath
gas researchers - defined a number of actions that a researcher is
conducting during the process of performing breath gas studies. We
have then mapped the specific actions to activities of the e-Science
life cycle. We also indicate where (on the community portal or
within MATLAB) these actions should be taken. The actions, its
corresponding e-Science life cycle activities, and the“place” where
they are taken are listed in Table 1.</p>
        <p>Based on this common understanding we are designing and
implementing the tools that support the breath gas researchers in
conducting their breath gas studies according to actions described
above.
2.2</p>
      </sec>
      <sec id="sec-2-2">
        <title>Breath Gas Analysis Dataspace Content</title>
        <p>
          The breath gas analysis scientific dataspace consists of a set of
databases set up by a dataspace designer and administered by a
dataspace manager. In particular, there are:
primary databases for storing the final input dataset. This kind
of datasets are being created after steps 1 to 7 of the use case
described above. They can be retrieved by submitting a query
to one of the breath gas research source databases available
to the acting researcher. However, in order to handle the issue
that data and probably also structure of the data might change
over time, we store this created final input dataset into a
separate database called primary database, which is designed
particularly for this purpose. A typical final input data set is less
than 1 MB in its MATLAB structure (.mat file), which is a
binary data container format used by MATLAB. It may include
arrays, variables, functions, and other types of data. It is
organized in three blocks as follows (
          <xref ref-type="bibr" rid="ref1">1</xref>
          ) patient data - includes
all collected data of different test persons such as proband value
(e.g. height, weight), burden (e.g. smoker/nonsmoker), labor
value (e.g. blood parameter), etc. (
          <xref ref-type="bibr" rid="ref2">2</xref>
          ) the system information
block manages all system settings for the two databases like
all users with their corresponding user groups, studies with
their questionnaires, different mass spectrometers with status,
container types with status, and (
          <xref ref-type="bibr" rid="ref3">3</xref>
          ) the analysis data part
includes all information on a specific measurement of a sample
such as mass spectrometer type, used container, collection date,
measurement date, data (substances with concentration and
additional information), etc.
background databases for storing the analytical methods used
to analyze the final input dataset i.e. MATLAB functions in
M-files (ASCII-textfiles containing MATLAB commands and
functions). Typical size of a single M-file is less that 500 KB.
derived databases for storing the results of analyses tasks.
Once the breath gas researcher has accomplished his
experiment, he can publish the results of his analysis. Therefore
we take advantage of MATLAB’s publishing function, which
lets you export results as plots or as complete reports. Using
the MATLAB editor, researchers can automatically export their
MATLAB results, including the code into XML and various
other file formats, e.g. HTML or LaTeX. Since typical breath
gas experiments include plotting functions, this dataset usually
includes jpg images. Typical size is less that 2 MB.
other databases i.e. volatomics databases, which contains data
from studies of exhaled breath gas as well as other sources of
endogenously-derived gases such as skin, urine, faeces, and
flatulence. There is a small number of mandatory data fields,
which will record basic metadata of studies of exhaled breath
gas. Records in this database will be based on a specific report
from some published source, such as a journal, conference
proceeding, or on-line publication. This means that records in
this database will be made only after the study has shown some
significant research results that were already scientifically
published.
        </p>
        <p>In addition there are special databases set up for storing the
instances of the e-Science life cycle ontology, which are defined
in RDF 2. This is based on using OGSA-DAI 19 to present an
RDF store. OGSA-DAI is the de facto standard for data access and
integration for relational and XML data as well as file resources.</p>
        <p>In contrast to data warehouse systems, data owners don’t lose
control over their data stored in above introduced participants of
the scientific dataspace. This is due to the publication concept
that is provided by the e-Science life cycle ontology (see Section
3). Breath gas researcher can limit access to their recources by
assinging different publication modes. Also, single breath gas
experiments and even whole studies can still be removed from
the dataspace by the corresponding data owner. Another important
distinction to data warehousing is in user management. The
scientific dataspace provides multiple research groups and types of
users to share their scientific resources without the time consuming
preparation of separate data marts as required in data warehousing.
Furthermore, in data warehousing systems data regularly need to
be extracted, cleaned, and loaded into the system; even though this
process is fully automated, it still consumes time as does regular
maintenance. This time commitment required is not the case with
the scientific dataspace paradigm because the data is loaded into the
corresponding databases, during execution of the experiment.</p>
        <p>Since patient data is involved and due to legal requirements on
such highly sensitive personal data, security and privacy issues
are of utmost importance. Thus within applications in the breath
gas analysis research domain, all participating databases including
the RDF store are isolated, monitored, and restricted to a single
point of access using the OGSA-DAI interface, hence implement
strict access control. An instance of the breath gas scientific
dataspace and its user environment is illustrated in Fig. 2. The
figure clearly shows that the dataspace consists of five databases
of types described above. Each is deployed as an OGSA-DAI
resource running on a secure virtual host in a virtual machine
resource. The recently developed logging framework inside
OGSADAI is used to detect data abuse. The OGSA-DAI services itself
are protected by standard security mechanisms supported by the
underlying container, which is in our case the Globus Toolkit
container 1 . We use mapping files in order to restrict access to
OGSA-DAI resources to specific users. Details about the access
control mechanisms and the security considerations in general are
described in 5, 6. There are many different tools available for
analyzing breath gas data (e.g. MATLAB, Octave, GridMiner, etc.).
Breath gas researchers are already used to some tools and therefore
might not want to change their analysis software. Therefore, we
were considering in our architecture to make the interface to
the scientific dataspace independent of any analysis tool. Users
access breath gas source data from their source database via the
community portal, which transforms the source dataset, using
wrappers into the format, which the corresponding tool can parse.
We provide interfaces for accessing data from and publishing data
into the dataspace by following the strict access control mechanisms
introduced above. The aim of the user environment is to guide
breath gas researcher through their experimentation and their data
publication by considering the e-Science life cycle ontology. Once
the scientific dataspace has grown into a large scientific resource,
we suspect it will be widely used by analysis, diagnostic and
visualization tools.</p>
        <p>Each instance of the above listed types of databases is defined as
dataspace-participant. On a lower level of abstraction the contents
of the databases itself are distinguished as dataspace-participants,
i.e the final input dataset or a single analysis function (M-file)
used within a specific breath gas analysis experiment. The different
levels of abstraction are illustrated in Fig. 3. On a higher level of
abstraction there might be whole dataspaces that act as participants
of an interconnected large-scale hyper-dataspace. Such scenarios
are important when multiple research organizations, each having
deployed their own dataspace, engage collaborations and agree
on sharing their scientific dataspaces and life cycle resources,
respectively.
3</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>METHODS</title>
      <p>Breath gas researchers will interact with the scientific dataspace via the
community Web portal as depicted in Fig. 2. A Web portal is a website that
Single Point of Access</p>
      <p>Anlaysis Tool 1</p>
      <p>Anlaysis Tool 2</p>
      <p>Anlaysis Tool 3</p>
      <p>Anlaysis Tool n
Instance of a Breath Gas Analysis Scientific Dataspace</p>
      <p>Single Point of Access</p>
      <p>VM Resource
Secure Virtual Host
OGSA‐DAI + Logging</p>
      <p>IABR_DBk</p>
      <p>
        SDB VM Resource
acts as a point of access for a wide variety of information. The community
portal consists of various portlets, which are pluggable components that are
managed by the portal. The portlets of the Web portal are categorized into
three major categories: (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) Infrastructure - Resource Management Portlets,
(
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) Monitoring - Semantic Logging Portlets, and (
        <xref ref-type="bibr" rid="ref3">3</xref>
        ) Action - Scientific
Dataspace Portlets. The first two categories are primarily for administrators
and therefore not further described in this paper. The latter category is
designed for the breath gas researcher. It consist of two portlets (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) the
eScience life cycle manager and (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) the dataspace browser. In the following,
the purpose and functionality of these two portlets are described and an
overview of the user interaction is given. The community portal is built
using the Google Web Toolkit (GWT) 13, which allows to build and maintain
complex yet highly performant JavaScript front-end applications in the Java
programming language, especially when combined with the Google Plugin
for Eclipse.
3.1
      </p>
      <sec id="sec-3-1">
        <title>The e-Science life cycle manager</title>
        <p>The e-Science life cycle manager is a tool that enables the breath
gas researcher to describe the experiment he is currently conducting
according to the activities of the e-Science life cycle model. The
model consists of five phases representing typical activities a researcher
is carrying out when performing scientific experiments. Thus the
most important steps in performing scientific experiments in e-Science
applications are classified into the five activities, which we named e-Science
life cycle activities (GoalSpecification, DataPreparation, TaskSelection,
TaskExecution, ResultPublishing) 9. The e-Science life cycle ontology
defines the concepts of the e-Science life cycle model as OWL-classes and
properties.</p>
        <p>The e-Science life cycle manager guides the breath gas researcher through
the above mentioned five e-Science life cycle activities. It creates new
instances of the e-Science life cycle and corresponding activities and allows
the researcher to refine them throughout his study. Already defined instances
of e-Science life cycle activities can be reused in other iterations or even in
other studies. For instance, a created final input dataset, which represents the
output of the activity DataPreparation might be reused in different iterations
of the same experiment or even in different studies. In order to find the
corresponding instance or other related instances for reuse we provide an
integrated search and query interface as described below.</p>
        <p>Search &amp; Query the dataspace - Dataspace systems must enable users to
interact with dataspaces through a search and query interface. However,
we should keep in mind that much of the interaction with such a system
is of exploratory nature. The implemented scientific dataspace model is
based on the e-Science life cycle ontology. Data about conducted breath gas
experiments is semantically rich described within instances of the ontology
and is stored in RDF format. Using SPARQL query language for RDF, the
scientific dataspace is able to provide answers to specific questions, such as
the following:</p>
        <p>A ”I have detected a model error and want to know which derived data
products need to be recomputed.”
B ”I want to check if insopiration is different to expiration of breath gas
dataset x. If the results already exist, I’ll save hours of computation.”
relationhip
Pk1</p>
        <p>Pj1
analytical method
Matlab Script</p>
        <p>M‐file</p>
        <p>Legend:
P… Dataspace Participant
SDS … Scientific Dataspace
LCR … Life Cycle Resource</p>
        <p>high
Fig. 3. Levels of abstraction of dataspace participants - in the lowest
abstraction level, participants of the scientific dataspace represent concrete
datasets that were used within a breath gas experiment. They form together
a Life Cycle Resource (LCR). In a particular breath gas experiment, these
participants are Pi1 - the final input dataset (primary data), Pj1 - the
analytical method as MATLAB commands and functions organized in a
m-file (background data), and Pk1 - the resulted analysis report generated
using MATLAB’s publish function (derived data). These participants are
stored in corresponding databases, as depicted in the figure. The relationship
among these participants is semantically rich described by individuals of
the e-Science life cycle ontology. In order to simplify matters we don’t
show in this figure the database that stores the relationships (RDF). On
the next abstraction level the databases DB1, DB2, and DB3 represent
participants forming the scientific dataspace SDS(Pi; Pj ; Pk), which is an
instance of a breath gas analysis dataspace as was deployed as experimental
framework for the Breath Research Institute of the Austrian Academy of
Sciences. On the top level we illustrate a large-scale hyper dataspace, that
arise when multiple dataspaces deployed for different organizations are
interconnected e.g multiple breath gas analysis research institutions engage
research collaborations, each running their own breath gas dataspace. In
this scenario the dataspaces itself represent participants of the large-scale
hyper-dataspace.</p>
        <p>relationship
relationship
DB1
PD Pi
Pi1</p>
        <p>P
P</p>
        <p>SDS1
P
DB2</p>
        <p>BD Pj
mapping</p>
        <p>P
relationship
DB3
DD Pk
relationship
analysis results
Matlab Report</p>
        <p>XML
final input dataset
masspecttrometer and
patient data
relational data</p>
        <p>LCR(Pi1,Pj1,Pk1)
relationship
C ”Is there any experiment done on the volatile organic compound
isoprene on exhaled breath gas in the context of cholesterol level in
blood?”</p>
        <p>SPARQL is a powerful query language for RDF data. However, strict
and complex grammar is a common characteristic of any query language
being proposed for structured data including SPARQL, SQL, XQuery, etc.
We are aware that it is not easy for breath gas researcher to accept these
languages. Keyword search is widely used in Web search engines, but it
cannot efficiently support semantic query. Therefore we implement a search
and query interface providing the breath gas researcher an easy way how to
express queries that will be transformed into a SPARQL query behind and
submitted to the RDF store.</p>
        <p>Neighborhood keyword queries - as introduced in 7, they have also the
goal to explore associations between data items, can be provided by the life
cycle ontology. For example searching for “endogenously-derived gases”
returns not only the goalSpecification instances available in the dataspace
that mention “endogenously-derived gases”, but also the instances of its
neighbor activities informing the user what proband data was used and where
it resides, which analytical methods were applied, and what results of the
corresponding experiment were achieved. Information about the scientist
who conducted the experiment is also returned. This will strongly enforce
new research collaboration within the breath gas research community.
Publication Modes - Different research groups are more or less collaborating
within the breath gas scientific community. A research group belongs to
a Regional Head Service (RHS). The RHS is responsible for managing a
country’s secure databases, which are under its ultimate control. The RHS
again belongs to a Project Head Service (PHS), which implements the access
decisions services, authentication, user management, and the dataspace
services implementing the functions described above 6.</p>
        <p>Users can publish their conducted e-Science life cycle experiments using
five different publication modes:
researcher - access to the instance of the life cycle can only be
accessed by a specific researcher i.e. the researcher who conducted the
experiment.
investigator - the instance will be accessible for investigators i.e. the
supervisor of a researcher.
research group - the life cycle instance will be available for members
of the research group the publisher is working with.
project member - the life cycle instance will be available for members
of the project the publisher is involved in.</p>
        <p>IABR member - the life cycle instance will be available for all members
of the IABR. In this case there will be an entry made into the volatomics
database
3.2</p>
      </sec>
      <sec id="sec-3-2">
        <title>The Dataspace Browser</title>
        <p>The dataspace browser is a tool that allows the user to navigate trough the
e-Science life cycle resources available in the dataspace in a visual way. It
is implemented as a portlet for easy integration into a community portal. It
submits SPARQL queries attached with the role of the requesting user to the
RDF Store. Based on the role of the user, he will see more or less e-Science
life cycle resources. For instance the scientific dataspace may contain life
cycle resources to which the publication mode Researcher was assigned.
Such life cycle resources should be only accessible for the researcher who
created the resource. Therefore, the request from the Dataspace Browser
will include the role of the user. The response represents RDF-data and is
used as input for the dataspace browser.</p>
        <p>There are a number of tools available that visualizes RDF data. Some
example projects include Welkin 20, multiple plugin tools for the Protege
environment 10, and Semantic Analytics Visualization 16. These tools could
also be used by breath gas researcher in order to browse the contents of the
dataspaces.
4</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>DISCUSSION</title>
      <p>In data warehousing data typically is extracted, transformed from
multiple data sources, and loaded into a separate database, called a
data warehouse. This is not the case with the scientific dataspace
paradigm discussed in this paper. Although, we load the final
input dataset prepared for an analysis task into a separate primary
database that is participating the dataspace. This is in fact one step
of the whole data life cycle in e-Science, which we are trying to
semantically enrich and preserve within the scientific dataspace.</p>
      <p>Experiments on exhaled breath gas are being successively refined
[iterations of action 4-6 in Table 1], by the acting researcher until
the study either shows a significant result (i.e. definition of accurate
methods for estimation of blood gas levels of certain biomarker
values from breath gas samples) [prepare action 7] or ends up in
a modification of the intended defined goal specification for that
experiment [modify goals and restart action 2]. However, in both
cases several iterations of the e-Science life cycle model are being
performed. Some instances of e-Science life cycle activities might
be reused in another iteration of the life cycle, for instance when
a breath gas researcher executes the same final input dataset on
a slightly refined analytical method. In this case the goals defined
and the data prepared for that experiment did not change, therefore
its corresponding instances of the e-Science life cycle activities are
being reused within a new iteration of the life cycle.</p>
      <p>During this iterative process of refinement, it might be the case
that the acting researcher needs to share the experiment with his
supervisor, who might decide to further share it with the research
group or even with members of a collaboration project. Finally,
once the study has shown some significant results that are published
in some journal or in proceedings of a conference etc., these
results represent valuable information not only to the acting research
group and it might be worth to publish the experiment using the
IABR member publication mode. Thus it will be accessible for all
members of the breath research association.
4.1</p>
      <sec id="sec-4-1">
        <title>Evaluating Studies</title>
        <p>During our investigations on the e-Science life cycle model, we
have cooperatively (computer scientists and breath gas researcher)
conducted several sample breath gas experiments on top of the
scientific dataspace. In the following we summarize the major
activities of those experiments and describe their outputs and how
data is organized by the scientific dataspace. At first the breath
gas study is described in textual form. Users can define their
own attributes and add values to it, e.g. attribute Description
contains a textual description of the goals of the sutdy. This data
is, together with information about the acting researcher (research
group, department, publication mode) saved as individuals of the
life cycle ontology in the RDF Store. A snapshot of a concrete RDF
graph of a sample breath gas experiment is illustrated in Fig. 4.</p>
        <p>
          Data access is done using the OGSA-DAI client and a certificate.
In most scenarios, the researcher first loads all values of a the dataset
he is investigating into the MATLAB structure. This is done using an
implemented data load MATLAB-function (loadData.m), which
communicates with an OGSA-DAI client. Then the breath gas
researcher selects the values he is interested in for the current
experiment, e.g. selection of all ex-smokers. The outputs of this
selection process, which is done within MATLAB are twofold:
(
          <xref ref-type="bibr" rid="ref1">1</xref>
          ) A new MATLAB MAT-structure containing the selected data
(fids.mat). This represents the final input dataset and is therefore
stored in the primary database as Binary Large Object (BLOB).
(
          <xref ref-type="bibr" rid="ref2">2</xref>
          ) The MATLAB function itself (selectData.m), which is
responsible to select the required data. This M-file represents the
background data and is therefore saved in the background database.
        </p>
        <p>Serveral analysis functions might be implemented by the breath
gas researcher and applied to the final input dataset. Such
MATLAB functions also represent background data, thus are
saved correspondingly. For easier handling we provide an empty
MATLAB file named executeStudy.m, which will be used
in all experiments. The breath gas researcher may add their own
implementations into it or import external analysis functions. These
functions calculate the derived data, which are usually input to
a plot function. Again an empty template (plotData.m) is
prepared to be used by the researcher. Finally we provide a publish
function (dsPublish.m), which generates an XML report of the
conducted experiment including plots, if used, by taking advantage
of MATLAB’s publishing feature. This report is then zipped and
saved as BLOB in the derived database of the scientific dataspace.</p>
        <p>Based on this investigations, we have created guidelines for breath
gas researchers, defining concrete activities and documentation
policies, which guide users through the e-Science live cycle. An
empty template with named files is also created for a better
comprehension.</p>
        <p>metaData</p>
        <p>describes
isDescribedBy
&lt;derivedData&gt;</p>
        <p>report.zip
hasAttributes
...</p>
        <p>Participant
&lt;backgroundData&gt;
selectData.m
executeStudy.m
plotData.m
hasAttributes
...</p>
        <p>...</p>
        <p>BGA Dataspace
consistsOf</p>
        <p>consistsOf
participatesIn</p>
        <p>participatesIn
describesRelationshipAmong</p>
        <p>isUsedIn
&lt;primaryData&gt;
fids.mat
hasAttributes
...</p>
        <p>hasAttributes
attributeName
Masspectrometer
correspondsTo
attributeValue</p>
        <p>PTR-MS</p>
        <p>LifeCycleResource</p>
        <p>ID:LCR111111
attributeName</p>
        <p>Type
correspondsTo
attributeValue
Masspectrometer
and patient data
Fig. 4. Snapshot of an RDF graph of a sample breath gas experiment - This
snapshot shows a life cycle resource, which describes the relationship of
the participants depicted in the figure. The participants represent primary,
background, and derived data of the breath gas experiment. Participants
are described with attributes and their values, which the acting breath gas
researcher defines, while conducting the experiment. In the breath gas
analysis domain, there is a set of attribute names predefined, to be followed
by scientists for a consistent description of breath gas analysis experiments.
A first experimental framework has been developed in order to
early evaluate the concepts of the e-Science life cycle ontology,
which is the basis of the scientific dataspace paradigm discussed
in this paper. This framework builds on top of Protege. We used
the built-in individual editor to create several life cycle resources
that represent breath gas analysis experiments and the SPARQL
query panel in order to retrieve those resources. Furthermore, we
deployed an experimental breath gas source database, restricted
to a single point of access using the OGSA-DAI interface and
implemented a MATLAB function that allows to communicate with
that database using a certificate. We then conducted several breath
gas experiments using the MATLAB environment and manually
saved its background and derived data into corresponding databases.
Even, if this first experimental framework has no interfaces
implemented, it allowed us to proof the concepts of the introduced
breath gas analysis scientific dataspace and to elaborate a feasibility
study. Based on this first experimental evaluations we have finalized
and documented the architecture of the system including the design
of all necessary OGSA-DAI workflows in an UML-based design
document to be available as technical report.</p>
        <p>As the next step we addressed the interface design, and started
to build a first prototype using the above introduced Google Web
Toolkit (GWT).
5</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>CONCLUSION</title>
      <p>This paper describes the proposal and implementation of a scientific
dataspace paradigm for the breath gas analysis scientific community.
The authors, computer scientists and leading breath gas researcher
have investigated and evaluated a novel data management and
scientific data preservation approach based on the concepts of
dataspaces for the scientific community of breath gas researcher.
First breath gas experiments were collaboratively conducted on
top of the experimental dataspace framework, which allowed us
to evaluate the e-Science life cycle ontology. This first evaluation
represents the bases for an extension and deeper investigation of the
scientific dataspace paradigm introduced.</p>
    </sec>
    <sec id="sec-6">
      <title>ACKNOWLEDGEMENT</title>
      <p>The Austrian BMWF (Federal Ministry for Science and Research)
funding of the Austrian Grid 2 project (Contract: GZ
BMWF10.220/0002-II/10/2007) is key to bringing the partners together
and to undertaking the research. The Department of Scientific
Computing, University of Vienna brought the e-Science life cycle
ontology to the project and the Research Center for Process and
Product Engineering, University of Applied Sciences, Dornbirn,
set up the meetings that led to the research collaboration with the
Breath Research Institute of the Austrian Academy of Sciences,
Innsbruck, forming the breath gas analysis application. The entire
research team contributed to the discussions that led to this paper
and provided the environment in which the ideas could be tested.
Finally we would like to thank the support from the e-Science
Institute for the hosting of the IWPLS09 workshop.</p>
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