11,496 research outputs found
Enhancing declarative process models with DMN decision logic
Modeling dynamic, human-centric, non-standardized and knowledge-intensive business processes with imperative process modeling approaches is very challenging. Declarative process modeling approaches are more appropriate for these processes, as they offer the run-time flexibility typically required in these cases. However, by means of a realistic healthcare process that falls in the aforementioned category, we demonstrate in this paper that current declarative approaches do not incorporate all the details needed. More specifically, they lack a way to model decision logic, which is important when attempting to fully capture these processes. We propose a new declarative language, Declare-R-DMN, which combines the declarative process modeling language Declare-R with the newly adopted OMG standard Decision Model and Notation. Aside from supporting the functionality of both languages, Declare-R-DMN also creates bridges between them. We will show that using this language results in process models that encapsulate much more knowledge, while still offering the same flexibility
A Meta-Analysis of Effects of Bt Crops on Honey Bees (Hymenoptera: Apidae)
L.) are the most important pollinators of many agricultural crops worldwide and are a key test species used in the tiered safety assessment of genetically engineered insect-resistant crops. There is concern that widespread planting of these transgenic crops could harm honey bee populations.We conducted a meta-analysis of 25 studies that independently assessed potential effects of Bt Cry proteins on honey bee survival (or mortality). Our results show that Bt Cry proteins used in genetically modified crops commercialized for control of lepidopteran and coleopteran pests do not negatively affect the survival of either honey bee larvae or adults in laboratory settings.Although the additional stresses that honey bees face in the field could, in principle, modify their susceptibility to Cry proteins or lead to indirect effects, our findings support safety assessments that have not detected any direct negative effects of Bt crops for this vital insect pollinator
Workplace career conversations: aligning organizational talent management and individual career development?
PURPOSE. This thesis takes a contextualised stakeholder approach to exploring alignment between organizational talent management and individual career development. The contribution and nature of career conversations as an opportunity for alignment is considered.
DESIGN. This qualitative study was conducted in two phases. Phase one involved semi-structured interviews with Human Resources and Organizational Development professionals (n = 30). Phase two involved semi-structured interviews using career narratives with line managers and individuals from five case study organizations which were also involved in phase 1 (n = 40). Data were analysed thematically by stakeholder group and within each case study.
LIMITATIONS. The sample used within the study were not selected to be representative. The conversations described by participants may not be representative of all of the conversations they have experienced. The case study organizations were all UK based.
FINDINGS. For most HR professionals, talent management was driven by organizational goals with little reference to individual needs, hence, alignment was not a priority for them. In contrast, individuals and line managers described a commitment to seeking overlap between organizational and individual goals, with some line managers describing their role as brokers . Career conversations were seen by all stakeholders as an important part of talent management and career development, with the potential to be a vehicle for alignment. Detailed analysis of the career conversations described by individuals identified a broad range of helpful conversations, the majority of which took place informally. Additional categories of career shaper (from Bosley et al, 2009) were also identified as collaborators and catalysts . A variety of contextual features were found to influence the enactment of talent management and career development. These were summarised as a contextual map indicating local, organisational and environmental dynamics.
ORIGINALITY/VALUE. The research reinforced the value of taking a contextualised perspective of both organizational talent and individual career (e.g. Cohen et al 2004; Sparrow, 2014). It also captured the voices of different stakeholder groups (e.g. Collings, 2014; Thunnissen et al, 2013)
Interestingness of traces in declarative process mining: The janus LTLPf Approach
Declarative process mining is the set of techniques aimed at extracting behavioural constraints from event logs. These constraints are inherently of a reactive nature, in that their activation restricts the occurrence of other activities. In this way, they are prone to the principle of ex falso quod libet: they can be satisfied even when not activated. As a consequence, constraints can be mined that are hardly interesting to users or even potentially misleading. In this paper, we build on the observation that users typically read and write temporal constraints as if-statements with an explicit indication of the activation condition. Our approach is called Janus, because it permits the specification and verification of reactive constraints that, upon activation, look forward into the future and backwards into the past of a trace. Reactive constraints are expressed using Linear-time Temporal Logic with Past on Finite Traces (LTLp f). To mine them out of event logs, we devise a time bi-directional valuation technique based on triplets of automata operating in an on-line fashion. Our solution proves efficient, being at most quadratic w.r.t. trace length, and effective in recognising interestingness of discovered constraints
Swift J053041.9-665426, a new Be/X-ray binary pulsar in the Large Magellanic Cloud
We observed the newly discovered X-ray source Swift J053041.9-665426 in the
X-ray and optical regime to confirm its proposed nature as a high mass X-ray
binary. We obtained XMM-Newton and Swift X-ray data, along with optical
observations with the ESO Faint Object Spectrograph, to investigate the
spectral and temporal characteristics of Swift J053041.9-665426. The XMM-Newton
data show coherent X-ray pulsations with a period of 28.77521(10) s (1 sigma).
The X-ray spectrum can be modelled by an absorbed power law with photon index
within the range 0.76 to 0.87. The addition of a black body component increases
the quality of the fit but also leads to strong dependences of the photon
index, black-body temperature and absorption column density. We identified the
only optical counterpart within the error circle of XMM-Newton at an angular
distance of ~0.8 arcsec, which is 2MASS J05304215-6654303. We performed optical
spectroscopy from which we classify the companion as a B0-1.5Ve star. The X-ray
pulsations and long-term variability, as well as the properties of the optical
counterpart, confirm that Swift J053041.9-665426 is a new Be/X-ray binary
pulsar in the Large Magellanic Cloud.Comment: 10 pages, 8 figures, accepted for publication in A&
Understanding transnational political involvement among Senegalese migrants: The role of acculturation preferences and perceived discrimination
In political debates, migrants' political involvement in their countries of origin and successful adaptation to receiving countries are often portrayed as incompatible. We address this concern by examining the links between acculturation preferences, perceived discrimination, and migrants' transnational political involvement in their country of origin. In line with collective action research, a cross-sectional questionnaire study (N = 84) among Senegalese migrants in Paris (France) and Geneva (Switzerland) examined three pathways to transnational political involvement (motivations and actual behaviour). Perceived discrimination, the grievances pathway, was positively related to both transnational motivations (but only when desire to adopt the receiving culture was low) and political behaviour in Senegal. Desire to adopt the culture of the receiving society as an acculturation preference, the embeddedness pathway, was also positively linked to transnational motivations and political behaviour. Finally, desire to maintain the culture of origin as an acculturation preference —the collective identification pathway— was unrelated to transnational political involvement. These findings underscore the compatibility of transnational political involvement in countries of origin and adaptation to receiving societies. We discuss the pivotal role Transnational political involvement in bringing together acculturation psychology and transnationalism studies
Discovery of a 168.8 s X-ray pulsar transiting in front of its Be companion star in the Large Magellanic Cloud
We report the discovery of LXP169, a new high-mass X-ray binary (XRB) in the
LMC. The optical counterpart has been identified and appears to exhibit an
eclipsing light curve. We performed follow-up observations to clarify the
eclipsing nature of the system. Energy spectra and time series were extracted
from two XMM-Newton observations to search for pulsations, characterise the
spectrum, and measure spectral and timing changes. Long-term X-ray variability
was studied using archival ROSAT data. The XMM positions were used to identify
the optical counterpart. We obtained UV to NIR photometry to characterise the
companion, along with its 4000 d long I-band light curve. We observed LXP169
with Swift at two predicted eclipse times. We found a spin period of 168.8 s
that did not change between two XMM observations. The X-ray spectrum, well
characterised by a power law, was harder when the source was brighter. The
X-ray flux of LXP169 is found to be variable by a factor of at least 10. The
counterpart is highly variable on short and long timescales, and its photometry
is that of an early-type star with a NIR excess. This classifies the source as
a BeXRB pulsar. We observed a transit in the UV, thereby confirming that the
companion star itself is eclipsed. We give an ephemeris for the transit of MJD
56203.877 + N*24.329. We propose and discuss the scenario where the matter
captured from the companion's equatorial disc creates an extended region of
high density around the neutron star (NS), which partially eclipses the
companion as the NS transits in front of it. This is most likely the first time
the compact object in an XRB is observed to eclipse its companion star. LXP169
would be the first eclipsing BeXRB, and a wealth of important information might
be gained from additional observations, such as a measure of the possible Be
disc/orbital plane misalignment, or the mass of the NS.Comment: Updated version of arXiv 1302.4665v1, accepted for publication in
Astronomy and Astrophysics. 11 pages, 8 figures, 3 table
Discovery of SXP265, a Be/X-ray binary pulsar in the Wing of the Small Magellanic Cloud
We identify a new candidate for a Be/X-ray binary in the XMM-Newton slew
survey and archival Swift observations that is located in the transition region
of the Wing of the Small Magellanic Cloud and the Magellanic Bridge. We
investigated and classified this source with follow-up XMM-Newton and optical
observations. We model the X-ray spectra and search for periodicities and
variability in the X-ray observations and the OGLE I-band light curve. The
optical counterpart has been classified spectroscopically, with data obtained
at the SAAO 1.9 m telescope, and photometrically, with data obtained using
GROND at the MPG 2.2 m telescope. The X-ray spectrum is typical of a high-mass
X-ray binary with an accreting neutron star. We detect X-ray pulsations, which
reveal a neutron-star spin period of P = (264.516+-0.014) s. The source likely
shows a persistent X-ray luminosity of a few 10^35 erg/s and in addition type-I
outbursts that indicate an orbital period of ~146 d. A periodicity of 0.867 d,
found in the optical light curve, can be explained by non-radial pulsations of
the Be star. We identify the optical counterpart and classify it as a
B1-2II-IVe star. This confirms SXP 265 as a new Be/X-ray binary pulsar
originating in the tidal structure between the Magellanic Clouds.Comment: 11 pages, 12 figures, accepted for publication in MNRA
XMM-Newton observation of SNR J0533-7202 in the Large Magellanic Cloud
Aims. We present an X-ray study of the supernova remnant SNR J0533-7202 in
the Large Magellanic Cloud (LMC) and determine its physical characteristics
based on its X-ray emission. Methods. We observed SNR J0533-7202 with
XMM-Newton (flare-filtered exposure times of 18 ks EPIC-pn and 31 ks
EPIC-MOS1/MOS2). We produced X-ray images of the SNR, performed an X-ray
spectral analysis, and compared the results to multi-wavelength studies.
Results. The distribution of X-ray emission is highly non-uniform, with the
south-west region brighter than the north-east. The X-ray emission is
correlated with the radio emission from the remnant. We determine that this
morphology is likely due to the SNR expanding into a non-uniform ambient medium
and not an absorption effect. We estimate the size to be 53.9 (\pm 3.4) x 43.6
(\pm 3.4) pc, with the major axis rotated ~64 degrees east of north. We find no
spectral signatures of ejecta and infer that the X-ray plasma is dominated by
swept-up interstellar medium. Using the spectral fit results and the Sedov
self-similar solution, we estimate an age of ~17-27 kyr, with an initial
explosion energy of (0.09-0.83) x 10^51 erg. We detected an X-ray source
located near the centre of the remnant, namely XMMU J053348.2-720233. The
source type could not be conclusively determined due to the lack of a
multi-wavelength counterpart and low X-ray counts. We find that it is likely
either a background active galactic nucleus or a low-mass X-ray binary in the
LMC. Conclusions. We detected bright thermal X-ray emission from SNR J0533-7202
and determined that the remnant is in the Sedov phase of its evolution. The
lack of ejecta emission prohibits us from typing the remnant with the X-ray
data. Therefore, the likely Type Ia classification based on the local stellar
population and star formation history reported in the literature cannot be
improved upon.Comment: 7 pages, 4 figures, accepted for publication in Astronomy and
Astrophysic
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